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1.
J Am Chem Soc ; 2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37916601

RESUMO

Lithium (Li)-metal batteries (LMBs) possess the highest theoretical energy density among current battery designs and thus have enormous potential for use in energy storage. However, the development of LMBs has been severely hindered by safety concerns arising from dendrite growth and unstable interphases on the Li anode. Covalent organic frameworks (COFs) incorporating either redox-active or anionic moieties on their backbones have high Li-ion (Li+) conductivities and mechanical/chemical stabilities, so are promising for solid electrolyte interphases (SEIs) in LMBs. Here, we synthesized anthraquinone-based silicate COFs (AQ-Si-COFs) that contained both redox-active and anionic sites via condensation of tetrahydroxyanthraquinone with silicon dioxide. The nine Li+-mediated charge/discharge processes enabled the AQ-Si-COF to demonstrate an ionic conductivity of 9.8 mS cm-1 at room temperature and a single-ion-conductive transference number of 0.92. Computational studies also supported the nine Li+ mechanism. We used AQ-Si-COF as the solid electrolyte interphase on the Li anode. The LMB cells with a LiCoO2 cathode attained a maximum reversible capacity of 188 mAh g-1 at 0.25 C during high-voltage operation. Moreover, this LMB cell demonstrated suppressed dendrite growth and stable cyclability, with its capacity decreasing by less than 3% up to 100 cycles. These findings demonstrate the effectiveness of our redox-active and anionic COFs and their practical utility as SEI in LMB.

2.
World J Diabetes ; 14(3): 234-254, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-37035233

RESUMO

BACKGROUND: Peripheral arterial disease (PAD) has become one of the leading causes of disa-bility and death in diabetic patients. Restoring blood supply to the hindlimbs, especially by promoting arteriogenesis, is currently the most effective strategy, in which endothelial cells play an important role. Tongxinluo (TXL) has been widely used for the treatment of cardio-cerebrovascular diseases and extended for diabetes-related vascular disease. AIM: To investigate the effect of TXL on diabetic PAD and its underlying mechanisms. METHODS: An animal model of diabetic PAD was established by ligating the femoral artery of db/db mice. Laser Doppler imaging and micro-computed tomography (micro-CT) were performed to assess the recovery of blood flow and arteriogenesis. Endothelial cell function related to arteriogenesis and cellular pyroptosis was assessed using histopathology, Western blot analysis, enzyme-linked immuno-sorbent assay and real-time polymerase chain reaction assays. In vitro, human vascular endothelial cells (HUVECs) and human vascular smooth muscle cells (VSMCs) were pretreated with TXL for 4 h, followed by incubation in high glucose and hypoxia conditions to induce cell injury. Then, indicators of HUVEC pyroptosis and function, HUVEC-VSMC interactions and the migration of VSMCs were measured. RESULTS: Laser Doppler imaging and micro-CT showed that TXL restored blood flow to the hindlimbs and enhanced arteriogenesis. TXL also inhibited endothelial cell pyroptosis via the reactive oxygen species/nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing 3/Caspase-1/GSDMD signaling pathway. In addition, TXL restored endothelial cell functions, including maintaining the balance of vasodilation, acting as a barrier to reduce inflammation, and enhancing endothelial-smooth muscle cell interactions through the Jagged-1/Notch-1/ephrin-B2 signaling pathway. Similar results were observed in vitro. CONCLUSION: TXL has a pro-arteriogenic effect in the treatment of diabetic PAD, and the mechanism may be related to the inhibition of endothelial cell pyroptosis, restoration of endothelial cell function and promotion of endothelial cell-smooth muscle cell interactions.

3.
J Vis Exp ; (194)2023 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-37092820

RESUMO

This study aims to show the estrogen-like effect of Bazi Bushen capsule (BZBS), a Chinese herbal compound, in ovariectomized mice. Female Sprague-Dawley (SD) rats were randomly divided into six groups: a sham-operated group, a model group (OVX), a progynova group, and BZBS groups (1, 2, and 4 d/kg/d). An ovariectomy was performed on all rats except those in the sham-operated group. Micro-computed tomography (micro-CT) scanning, hematoxylin and eosin (H&E) staining, immunohistochemistry, and enzyme-linked immunosorbent assay (ELISA) detection were performed after 4 months of BZBS treatment. As a result, compared with the OVX group, rats treated with BZBS showed an increased number and area of trabecular bone and bone marrow cells, and a decreased number of adipose cells. The bone volume, trabecular number, and trabecular thickness of the right tibia in the medication groups increased and the trabecular space decreased. The 17ß-estradiol and serum calcium levels in the medication groups were elevated, but the levels of serum phosphorus, sclerostin, ß-CTX, and TRACP-5b were decreased. In the medication groups, the RANKL and sclerostin levels were decreased, while the osteoprotegerin (OPG) level was increased. In conclusion, this protocol systematically evaluated the therapeutic effects and potential molecular mechanisms of Chinese herbal compounds in ovariectomized rats with a variety of techniques.


Assuntos
Estradiol , Tíbia , Ratos , Feminino , Animais , Camundongos , Ratos Sprague-Dawley , Microtomografia por Raio-X , Estradiol/farmacologia , Estrogênios/farmacologia
4.
Drug Des Devel Ther ; 17: 313-330, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36776448

RESUMO

Purpose: The aim of our study was to investigate the mechanism by which the Chinese compound Shensong Yangxin Capsule (SSYX) reduces susceptibility to arrhythmia in db/db mice. Methods: The db/db mice without drug treatment served as the model group. Other-treated db/db mice were administered SSYX for 8 weeks. Electrocardiogram (ECG), electrical mapping, pathological changes, immunofluorescence staining, real-time quantitative PCR, and Western blot analyses were then conducted. Results: SSYX decreased arrhythmia susceptibility and shortened the abnormal ECG parameters of db/db mice. Meanwhile, SSYX restored irregular conduction direction and shortened the conduction time of the isolated heart. HE and Masson staining showed that SSYX alleviated inflammatory infiltration and collagen fiber deposition. Western blot showed that SSYX decreased the protein expression of ICAM-1, VCAM-1, and MCP-1 and increased the protein expression of occludin, ZO-1, eNOS, and Cx43. SSYX also increased the content of NO, decreased ET-1, TNF-α, IL-1ß, IL-6, MCP-1, and CCR-2 mRNA expression, and increased Kv 4.2, Kv 4.3, Cav 1.2, and Nav 1.5 mRNA expression. Furthermore, SSYX decreased the fluorescence intensity of F4/80 and iNOS, increased the fluorescence intensity of CD31 and eNOS, and improved the Cx43 and α-actinin connection structure in cardiac tissues. The above therapeutic effects of SSYX were inhibited by L-NAME. Conclusion: SSYX reduced the susceptibility of db/db mice to arrhythmia by inhibiting the inflammatory response and macrophage polarization, and this effect of SSYX occurred through protection of endothelial cell function.


Assuntos
Conexina 43 , Medicamentos de Ervas Chinesas , Camundongos , Animais , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Arritmias Cardíacas/tratamento farmacológico , Endotélio , RNA Mensageiro
5.
J Cardiovasc Transl Res ; 16(1): 127-140, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35616880

RESUMO

Heart failure with preserved ejection fraction (HFpEF) is a common public health problem associated with increased morbidity and long-term mortality. However, effective treatment for HFpEF was not discovered yet. In the present study, we aimed to decipher the effects of Periplocin on DOCA-induced heart failure rats and explore the possible underlying mechanisms. We demonstrated that Periplocin could significantly attenuate cardiac structural remodeling and improve cardiac diastolic function. Of note, Periplocin significantly inhibited the recruitment of inflammatory and immune cells and decreased the expression of serum inflammatory cytokines. Meanwhile, Periplocin had the effect of cardiac glycosides to improve cardiomyocyte contractility and calcium transient amplitude. These findings indicate that Periplocin might be a potential medicine to treat HFpEF in patients.


Assuntos
Acetato de Desoxicorticosterona , Insuficiência Cardíaca , Ratos , Animais , Remodelação Ventricular , Volume Sistólico , Miócitos Cardíacos/metabolismo
6.
Nanoscale ; 14(11): 4082-4088, 2022 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-35234769

RESUMO

Monolayer blue phosphorous has a large band gap of 2.76 eV but counterintuitively the most stable bilayer blue phosphorous has a negative band gap of -0.51 eV. Such a large band gap reduction from just monolayer to bilayer has not been revealed before, the underlying mechanism behind which is important for understanding interlayer interactions. In this work, we reveal the origin of the semiconductor-to-metal transition using first-principles calculations and tight-binding models. We find that the interlayer interactions are extremely strong, which can be attributed to the short layer distance and strong π-like atomic orbital couplings. Therefore, the upshift of the valence band maximum (VBM) from monolayer to bilayer blue-P is so large that the VBM in the bilayer gets higher than the conduction band minimum, leading to a negative band gap and an energy gain. Besides, the interlayer atomic misplacements weaken the couplings of out-of-plane orbitals. Therefore, the energy gain due to the semiconductor-to-metal transition is larger than the energy cost due to interlayer repulsions, thus stabilizing the metallic phase. The large band gap reduction with layer number increasing is expected to exist in other similar layered systems.

7.
Nanoscale ; 13(35): 14621-14627, 2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34533551

RESUMO

Interlayer interactions play important roles in manipulating the electronic properties of layered semiconductors. One common mechanism is that the valence band maximum (VBM) and the conduction band minimum (CBM) in one layer couple to the VBM and CBM in another layer, respectively, resulting in the decrease of the band gap from the monolayer to the bilayer. Here we report an unusual interlayer coupling mechanism in layered Cu-based ternary chalcogenides CuMCh2 (M = Sb, Bi; Ch = S, Se) that the CBM in one layer strongly couples to the VBM in the other layer, leading to the band gap increase from the monolayer to the bilayer. Such an unusual interlayer interaction arises from the entangling between the electronic structures and the structures of CuMCh2 in which the cations M and anions Ch are alternatively arranged at the outmost part of each layer. Consequently, the M atom at the bottom of the upper layer is very close to the Ch atom at the top of the bottom layer, so that the orbitals of the M atom which dominate the CBM can strongly couple to the orbitals of the Ch atom which dominate the VBM, as demonstrated by the orbital hopping integrals obtained from the Wannier function analysis. The exceptional case of the unusual interlayer interaction revealed in this work enriches the diversity of the interlayer interactions in layered materials and is expected to exist in similar layered systems in which cations and anions are alternatively arranged at the outmost part of each layer.

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