Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
Más filtros










Intervalo de año de publicación
1.
Angew Chem Int Ed Engl ; 63(25): e202405427, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38603586

RESUMEN

Neutral aqueous organic redox flow batteries (AORFBs) hold the potential to facilitate the transition of renewable energy sources from auxiliary to primary energy, the commercial production of anolyte materials still suffers from insufficient performance of high-concentration and the high cost of the preparation problem. To overcome these challenges, this study provides a hydrothermal synthesis methodology and introduces the charged functional groups into hydrophobic naphthalene diimide cores, and prepares a series of high-performance naphthalene diimide anolytes. Under the synergistic effect of π-π stacking and H-bonding networks, the naphthalene diimide exhibits excellent structural stability and the highest water solubility (1.85 M for dex-NDI) reported to date. By employing the hydrothermal method, low-cost naphthalene diimides are successfully synthesized on a hundred-gram scale of $0.16 g-1 ($2.43 Ah-1), which is also the lowest price reported to date. The constructed full battery achieves a high electron concentration of 2.4 M, a high capacity of 54.4 Ah L-1, and a power density of 318 mW cm-2 with no significant capacity decay observed during long-duration cycling. These findings provide crucial support for the commercialization of AORFBs and pave the way for revolutionary developments in neutral AORFBs.

2.
ACS Appl Mater Interfaces ; 14(43): 48727-48733, 2022 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-36257057

RESUMEN

A series of chalcogenophene viologens ([(NPr)2FV]Cl4, [(NPr)2TV]Cl4, and [(NPr)2SeV]Cl4) as anolytes for neutral aqueous organic redox flow batteries (AORFBs) via a combination of chalcogenophenes (furan, thiophene, and selenophene) and viologens are reported. The chalcogenophene viologens showed narrow HOMO-LUMO energy gap, high solubility, and stable electrochemical properties. Compared with the parent [(NPr)2V]Cl4, the introduction of π-conjugated chalcogenophene groups reduced the redox potential and enhanced the stability of their free radical state, which endowed the chalcogenophene viologens/FcNCl-based AORFBs with a higher theoretical battery voltage of 1.20 V and enhanced stability for one-electron storage. In particular, the [(NPr)2FV]Cl4/FcNCl-based AORFB exhibited excellent long-cycle stability for 3000 cycles with 0.0006% capacity decay per cycle for one-electron storage and 300 cycles with 0.06% capacity decay per cycle for two-electron storage at a charge voltage of 1.9 V (1.42 V theoretical battery voltage). This work provided a new strategy for regulating the voltage and improving the performance of neutral AORFBs.

3.
Cell Discov ; 8(1): 53, 2022 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-35668062

RESUMEN

The spike (S) protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an important target for vaccine and drug development. However, the rapid emergence of variant strains with mutated S proteins has rendered many treatments ineffective. Cleavage of the S protein by host proteases is essential for viral infection. Here, we discovered that the S protein contains two previously unidentified Cathepsin L (CTSL) cleavage sites (CS-1 and CS-2). Both sites are highly conserved among all known SARS-CoV-2 variants. Our structural studies revealed that CTSL cleavage promoted S to adopt receptor-binding domain (RBD) "up" activated conformations, facilitating receptor-binding and membrane fusion. We confirmed that CTSL cleavage is essential during infection of all emerged SARS-CoV-2 variants (including the recently emerged Omicron variant) by pseudovirus (PsV) infection experiment. Furthermore, we found CTSL-specific inhibitors not only blocked infection of PsV/live virus in cells but also reduced live virus infection of ex vivo lung tissues of both human donors and human ACE2-transgenic mice. Finally, we showed that two CTSL-specific inhibitors exhibited excellent In vivo effects to prevent live virus infection in human ACE2-transgenic mice. Our work demonstrated that inhibition of CTSL cleavage of SARS-CoV-2 S protein is a promising approach for the development of future mutation-resistant therapy.

4.
Bioresour Technol ; 333: 125182, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33906015

RESUMEN

A new hybrid system is proposed to capture CO2 as well as generate electricity with the low CO2 inlet condition of confined space. Within the system, a novel photocatalytic porous framework coated by g-C3N4/TiO2 is prepared to avoid the inhibition of microalgae growth caused by the direct addition of photocatalyst. Under 0.8% v/v CO2 inlet condition, chemical oxygen demand (COD) yields from the photocatalytic framework immersed in the phosphate buffer and the algae suspension are 1.63 mg L-1 h-1 and 1.90 mg L-1 h-1, respectively. CO2 sequestration rate of a 60L cylindrical photobioreactor increases from 12% to 22%. The combination modes between photobioreactor and photocatalytic framework can be selected flexibly depends on the demands of application. This hybrid system not only benefits to enhance the CO2 sequestration rate of photobioreactor but also has the potential to be served as the power source in a confined space.


Asunto(s)
Fuentes de Energía Bioeléctrica , Microalgas , Dióxido de Carbono , Secuestro de Carbono , Fotobiorreactores , Porosidad
5.
Pain ; 158(4): 717-739, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28225710

RESUMEN

Exacerbation of pain by chronic stress and comorbidity of pain with stress-related psychiatric disorders, including anxiety and depression, represent significant clinical challenges. However, the underlying mechanisms still remain unclear. Here, we investigated whether chronic forced swim stress (CFSS)-induced exacerbation of neuropathic pain is mediated by the integration of stress-affect-related information with nociceptive information in the central nucleus of the amygdala (CeA). We first demonstrated that CFSS indeed produces both depressive-like behaviors and exacerbation of spared nerve injury (SNI)-induced mechanical allodynia in rats. Moreover, we revealed that CFSS induces both sensitization of basolateral amygdala (BLA) neurons and augmentation of long-term potentiation (LTP) at the BLA-CeA synapse and meanwhile, exaggerates both SNI-induced sensitization of CeA neurons and LTP at the parabrachial (PB)-CeA synapse. In addition, we discovered that CFSS elevates SNI-induced functional up-regulation of GluN2B-containing NMDA (GluN2B-NMDA) receptors in the CeA, which is proved to be necessary for CFSS-induced augmentation of LTP at the PB-CeA synapse and exacerbation of pain hypersensitivity in SNI rats. Suppression of CFSS-elicited depressive-like behaviors by antidepressants imipramine or ifenprodil inhibits the CFSS-induced exacerbation of neuropathic pain. Collectively, our findings suggest that CFSS potentiates synaptic efficiency of the BLA-CeA pathway, leading to the activation of GluN2B-NMDA receptors and sensitization of CeA neurons, which subsequently facilitate pain-related synaptic plasticity of the PB-CeA pathway, thereby exacerbating SNI-induced neuropathic pain. We conclude that chronic stress exacerbates neuropathic pain via the integration of stress-affect-related information with nociceptive information in the CeA.


Asunto(s)
Núcleo Amigdalino Central/fisiología , Neuralgia/complicaciones , Estrés Psicológico/complicaciones , Potenciales de Acción/fisiología , Animales , Peso Corporal/fisiología , Núcleo Amigdalino Central/citología , Núcleo Amigdalino Central/efectos de los fármacos , Modelos Animales de Enfermedad , Preferencias Alimentarias/psicología , Hiperalgesia/fisiopatología , Locomoción/fisiología , Potenciación a Largo Plazo/efectos de los fármacos , Potenciación a Largo Plazo/fisiología , Masculino , Aprendizaje por Laberinto/fisiología , Neuronas/fisiología , Umbral del Dolor/fisiología , Ratas , Ratas Sprague-Dawley , Sacarosa , Natación/psicología , Sinaptosomas/metabolismo
6.
J Nanosci Nanotechnol ; 15(4): 3048-54, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26353534

RESUMEN

In this work, the influence of temperature and humidity environment on the water vapor adsorption capacity and effective thermal conductivity of silica nano-porous material is conducted within a relative humidity range from 15% to 90% at 25 °C, 40 °C and 55 °C, respectively. The experiment results show that both the temperature and relative humidity have significant influence on the adsorption capacity and effective thermal conductivity of silica nano-porous materials. The adsorption capacity and effective thermal conductivity increase with humidity because of the increases of water vapor concentration. The effective thermal conductivity increases linearly with adsorption saturation capacity at constant temperature. Because adsorption process is exothermic reaction, the increasing temperature is not conducive to the adsorption. But the effective thermal conductivity increases with the increment of temperature at the same water uptake because of the increment of water thermal conductivity with temperature Geometric models and unit cell structure are adopted to predict the effective thermal conductivity and comparisons with the experimental result are made, and for the case of moist silica nano-porous materials with high porosity no quantitative agreement is found. It is believed that the adsorbed water will fill in the nano-pores and gap and form lots of short cuts, leading to a significant reduction of the thermal resistance.

7.
Appl Opt ; 48(25): F55-60, 2009 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-19724314

RESUMEN

By combination of two defect structures with positive and negative birefringence, we design a holey fiber with a beat length that is less sensitive to wavelength. The influence of different structural parameters on birefringence of holey fiber is calculated by the finite-difference beam propagation method. A stable beat length can be achieved at some given wavelength window by adjusting the parameters. An almost uniform beat length with a greater than 180 nm bandwidth at 1310 and 1550 nm wavelength windows is obtained, which is useful for the design and fabrication of fiber-optic wave plates with a wide band.

8.
Exp Neurol ; 215(2): 298-307, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19046970

RESUMEN

Activation of N-methyl-d-aspartate (NMDA) receptors in the spinal dorsal horn has been shown to be essential for the initiation of central sensitization and the hyperexcitability of dorsal horn neurons in chronic pain. However, whether the spinal NR2B-containing NMDA (NMDA-2B) receptors are involved still remains largely unclear. Using behavioral test and in vivo extracellular electrophysiological recording in L5 spinal nerve-ligated (SNL) neuropathic rats, we investigate the roles of spinal cord NMDA-2B receptors in the development of neuropathic pain. Our study showed that intrathecal (i.t.) injection of Ro 25-6981, a selective NMDA-2B receptor antagonist, had a dose-dependent anti-allodynic effect without causing motor dysfunction. Furthermore, i.t. application of another NMDA-2B receptor antagonist ifenprodil prior to SNL also significantly inhibited the mechanical allodynia but not the thermal hyperalgesia. These data suggest that NMDA-2B receptors at the spinal cord level play an important role in the development of neuropathic pain, especially at the early stage following nerve injury. In addition, spinal administration of Ro 25-6981 not only had a dose-dependent inhibitory effect on the C-fiber responses of dorsal horn wide dynamic range (WDR) neurons in both normal and SNL rats, but also significantly inhibited the long-term potentiation (LTP) in the C-fiber responses of WDR neurons induced by high-frequency stimulation (HFS) applied to the sciatic nerve. These results indicate that activation of the dorsal horn NMDA-2B receptors may be crucial for the spinal nociceptive synaptic transmission and for the development of long-lasting spinal hyperexcitability following nerve injury. In conclusion, the spinal cord NMDA-2B receptors play a role in the development of central sensitization and neuropathic pain via the induction of LTP in dorsal horn nociceptive synaptic transmission. Therefore, the spinal cord NMDA-2B receptor is likely to be a target for clinical pain therapy.


Asunto(s)
Neuralgia/patología , Neuralgia/fisiopatología , Receptores de N-Metil-D-Aspartato/metabolismo , Médula Espinal/metabolismo , Potenciales de Acción/efectos de los fármacos , Potenciales de Acción/fisiología , Análisis de Varianza , Animales , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Estimulación Eléctrica , Antagonistas de Aminoácidos Excitadores/farmacología , Antagonistas de Aminoácidos Excitadores/uso terapéutico , Hiperalgesia/fisiopatología , Potenciación a Largo Plazo/efectos de los fármacos , Potenciación a Largo Plazo/fisiología , Masculino , Actividad Motora/fisiología , Fibras Nerviosas/efectos de los fármacos , Fibras Nerviosas/fisiología , Neuralgia/tratamiento farmacológico , Dimensión del Dolor , Umbral del Dolor/fisiología , Fenoles/farmacología , Fenoles/uso terapéutico , Piperidinas/farmacología , Piperidinas/uso terapéutico , Ratas , Ratas Sprague-Dawley , Células Receptoras Sensoriales/efectos de los fármacos , Células Receptoras Sensoriales/fisiología , Médula Espinal/patología , Factores de Tiempo
9.
Chinese Medical Journal ; (24): 183-188, 2004.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-235807

RESUMEN

<p><b>BACKGROUND</b>An increasing incidence of Crohn's disease has been found in China in recent years. Our study has been focused on evaluating the diversity of the clinical manifestations of Crohn's disease in order to improve early diagnostic accuracy and therapeutic efficacy.</p><p><b>METHODS</b>Thirty patients with active Crohn's disease were enrolled and their clinical data, including diagnostic and therapeutic results, were analyzed. Endoscopy combined with histological examination of biopsy specimens provided characteristic features of the disease. Transabdominal bowel sonography (TABS) was used for detecting intestinal complications. Nutritional supportive therapy was given to 20 subjects with active cases of the disease.</p><p><b>RESULTS</b>Most patients were young adults with a higher proportion of females to males (ratio: 1.14:1). The disease affects any segment or a combination of segments along with the alimentary tract (from the mouth to the anus). In this study, the colon and small bowel were the major sites involved. Recurrent episodes of abdominal pain in the right lower quadrant and watery diarrhea were the most common symptoms. Granulomas were identifiable in nearly one-third (30.8%) of all biopsy specimens. In moderate cases of the disease, remission was achieved more quickly through the use of oral prednisone therapy than with SASP or 5-ASA. Beneficial effects on the host's nutritional status were observed. Immunosuppressives were used on an individual basis and showed variable therapeutic effects. Sixteen patients had surgery due to intestinal obstruction or failure to respond to drug therapies. Rapid improvement after surgery was reported.</p><p><b>CONCLUSION</b>Endoscopy (with biopsy) and TABS were both crucial procedures for diagnosis. SASP (or 5-ASA) and prednisone were effective as inductive therapies. Azathioprine has demonstrable benefits after induction therapy with prednisone. Surgery, as an alternative treatment, provided another effective choice in selected patients.</p>


Asunto(s)
Adolescente , Adulto , Anciano , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Azatioprina , Usos Terapéuticos , Biopsia , Enfermedad de Crohn , Diagnóstico , Diagnóstico por Imagen , Terapéutica , Endoscopía Gastrointestinal , Mesalamina , Prednisona , Sulfasalazina , Ultrasonografía
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...