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1.
Chem Commun (Camb) ; 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38629259

RESUMO

Alkylamines with different chain lengths including n-butylamine, n-hexylamine, and n-octylamine, are applied to regulate the CsPbIBr2 perovskite film quality by strain engineering. The status of residual strains is controllably modulated, resulting in improved efficiency and stability of carbon-based hole-transport-material free CsPbIBr2 perovskite solar cells.

3.
ACS Appl Mater Interfaces ; 16(12): 14974-14983, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38489750

RESUMO

Perovskite solar cells (PSCs) have attracted extensive attention in photovoltaic applications owing to their superior efficiency, and the buried interface plays a significant role in determining the efficiency and stability of PSCs. Herein, a plant-derived small molecule, ergothioneine (ET), is adopted to heal the defective buried interface of CsPbIBr2-based PSC to improve power conversion efficiency (PCE). Because of the strong interaction between Lewis base groups (-C═O and -C═S) in ET and uncoordinated Pb2+ in the perovskite film from the theoretical simulations and experimental results, the defect density of the CsPbIBr2 perovskite film is significantly reduced, and therefore, the nonradiative recombination in the corresponding device is simultaneously suppressed. Consequently, the target device achieves a high PCE of 11.13% with an open-circuit voltage (VOC) of 1.325 V for hole-free, carbon-based CsPbIBr2 PSCs and 14.56% with a VOC of 1.308 V for CsPbI2Br PSCs. Furthermore, because of the increased ion migration energy, the detrimental phase segregation in this mixed-halide perovskite is weakened, delivering excellent long-term stability for the unencapsulated device in ambient conditions over 70 days with a 96% retention rate of initial efficiency.

5.
Angew Chem Int Ed Engl ; 63(12): e202318784, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38291557

RESUMO

Plitidepsin (or dehydrodidemnin B), an approved anticancer drug, belongs to the didemnin family of cyclic depsipeptides, which are found in limited quantities in marine tunicate extracts. Herein, we introduce a new approach that integrates microbial and chemical synthesis to generate plitidepsin and its analogues. We screened a Tistrella strain library to identify a potent didemnin B producer, and then introduced a second copy of the didemnin biosynthetic gene cluster into its genome, resulting in a didemnin B titer of approximately 75 mg/L. Next, we developed two straightforward chemical strategies to convert didemnin B into plitidepsin, one of which involved a one-step synthetic route giving over 90 % overall yield. Furthermore, we synthesized 13 new didemnin derivatives and three didemnin probes, enabling research into structure-activity relationships and interactions between didemnin and proteins. Our study highlights the synergistic potential of biosynthesis and chemical synthesis in overcoming the challenge of producing complex natural products sustainably and at scale.


Assuntos
Antineoplásicos , Depsipeptídeos , Peptídeos Cíclicos/farmacologia , Peptídeos Cíclicos/metabolismo , Depsipeptídeos/farmacologia , Antineoplásicos/farmacologia , Relação Estrutura-Atividade
6.
Langmuir ; 40(2): 1286-1294, 2024 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-38171006

RESUMO

Nitric oxide (NO)-releasing coating is promising to enhance the biocompatibility of medical devices. In this study, polyurethane (PU) and S-nitrosated keratin (KSNO) were dissolved with dimethyl sulfoxide (DMSO) and tetrahydrofuran (THF) to prepare a coating solution. This solution is facile to form a porous coating on various substrates based on solvent-evaporation-induced phase separation (SEIPS). The coating could continuously release NO up to 200 h in the presence of ascorbic acid (Asc). In addition, the coating could accelerate endothelialization by promoting the viability of human umbilical vein endothelial cells (HUVECs) while inhibiting the proliferation of human umbilical artery smooth muscle cells (HUASMCs). Furthermore, the coating had good antibacterial activity and blood compatibility. Taken together, this universal coating provides wider potential applications in the field of cardiovascular implants.


Assuntos
Antibacterianos , Óxido Nítrico , Humanos , Óxido Nítrico/farmacologia , Porosidade , Células Endoteliais da Veia Umbilical Humana , Antibacterianos/farmacologia , Materiais Revestidos Biocompatíveis/farmacologia
7.
Clin Appl Thromb Hemost ; 30: 10760296231221772, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38166398

RESUMO

This study investigated the efficacy and safety of pharmaco-invasive strategy with half-dose recombinant human prourokinase (PHDP) during hospitalization for patients with ST-segment elevation myocardial infarction (STEMI) to provide references for the treatment of STEMI. Patients with STEMI who fulfilled the inclusion and exclusion criteria and attended Chengde Central Hospital, Hebei Province, China, between September 3, 2019, and December 28, 2021, were included in this study. The experimental group received PHDP and the control group underwent primary percutaneous coronary intervention (PPCI). This study enrolled 150 patients with STEMI, 75 in the experimental group and 75 in the control group. Coronary angiography revealed successful thrombolysis in 64 (85.33%) patients. Compared with the control group, the experimental group had shorter first medical contact-reperfusion time (P < 0.001), less slow flow/no-reflow (P < 0.001), and a lower utilization rate of Tirofiban (P < 0.001). Validity endpoints: no statistically significant differences between the two groups. Safety endpoints: no statistically significant differences between bleeding and major adverse cardiovascular and cerebrovascular events (MACCEs), but the experimental group was more prone to arrhythmias (P = 0.040), particularly premature ventricular beats (PVB) (P = 0.008). In conclusion, the efficacy and safety of PHDP in the treatment of patients with STEMI were positive. Complete epicardial and myocardial reperfusion rates, risk for bleeding during hospitalization, and incidence of MACCEs were similar to those of the PPCI strategy. Although the PHDP group has a higher incidence of PVB, it does not increase the incidence of malignant arrhythmia. This study aimed to provide a new therapeutic strategy for the treatment of STEMI in hospitals without adequate PPCI resources condition.


Assuntos
Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Fibrinolíticos/efeitos adversos , Infarto do Miocárdio com Supradesnível do Segmento ST/tratamento farmacológico , Infarto do Miocárdio com Supradesnível do Segmento ST/cirurgia , Resultado do Tratamento , Intervenção Coronária Percutânea/efeitos adversos , Hemorragia/induzido quimicamente , Hospitalização
8.
Sensors (Basel) ; 23(22)2023 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-38005648

RESUMO

Geohazards, such as landslides, rock avalanches, debris flow, ground fissures, and ground subsidence, pose significant threats to people's lives and property [...].

9.
Artigo em Inglês | MEDLINE | ID: mdl-37905186

RESUMO

Background: Microglia are closely linked to Alzheimer's disease (AD) many years ago; however, the pathological mechanisms of AD remain unclear. The purpose of this study was to determine whether leptin affected microglia in the hippocampus of young and aged male APP/PS1 mice. Objective: In a transgenic model of AD, we investigated the association between intraperitoneal injection of leptin and microglia. Methods: We intraperitoneal injection of leptin (1mg/kg) every day for one week and analyzed inflammatory markers in microglia in the hippocampus of adult (6 months) and aged (12 months) APP/PS1 mice. Results: In all leptin treatment group, the brain Aß levels were decrease. We found increased levels of IL-1ß, IL-6 and microglial activation in the hippocampus of adult mice. Using aged mice as an experimental model for chronic neuroinflammation and leptin resistance, the number of Iba-1+ microglia and the levels of IL-1ß/IL-6 in the hippocampus were greatly increased as compared to the adult. But between the leptin treatment and un-treatment, there were no difference. Conclusion: Leptin signaling would regulate the activation of microglia and the release of inflammatory factors, but it is not the only underlying mechanism in the neuroprotective effects of AD pathogenesis.

11.
Adv Mater ; 35(30): e2301684, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37120149

RESUMO

It is challenging to achieve long-term stability of perovskite solar cells due to the corrosion and diffusion of metal electrodes. Integration of compact barriers into devices has been recognized as an effective strategy to protect the perovskite absorber and electrode. However, the difficulty is to construct a thin layer of a few nanometers that can delay ion migration and impede chemical reactions simultaneously, in which the delicate microstructure design of a stable material plays an important role. Herein, ZrNx barrier films with high amorphization are introduced in p-i-n perovskite solar cells. To quantify the amorphous-crystalline (a-c) density, pattern recognition techniques are employed. It is found the decreasing a-c interface in an amorphous film leads to dense atom arrangement and uniform distribution of chemical potential, which retards the interdiffusion at the interface between ions and metal atoms and protect the electrodes from corrosion. The resultant solar cells exhibit improved operational stability, which retains 88% of initial efficiency after continuous maximum power point tracking under 1-Sun illumination at room temperature (25 °C) for 1500 h.

12.
Dalton Trans ; 52(18): 6146-6151, 2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37073582

RESUMO

All-inorganic CsPbBr3 perovskite solar cells have received growing attention in the photovoltaic field due to their high stability, low cost, and simple preparation processes. However, the high-density defects in perovskite films and the large energy differences at interfaces have been the main challenges for achieving high power conversion efficiency and good stability. In this work, nickel oxide (NiOx) decorated graphene oxide (GO) is used as a hole collector at the perovskite/carbon interface for a carbon-based CsPbBr3 perovskite solar cell. The crystallinity of the CsPbBr3 perovskite layer and the hole extraction ability are markedly enhanced because of the p-type charge transfer doping of GO from oxygenic groups to NiOx. Finally, the all-inorganic CsPbBr3 perovskite solar cell achieves a power conversion efficiency of 8.59%. More importantly, the best solar cell free of encapsulation retains 94.2% of its initial efficiency in an air environment over 21 days.

13.
Chem Commun (Camb) ; 59(31): 4608-4611, 2023 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-36976547

RESUMO

A photovoltaic-hydrovoltaic-coupled carbon-based, all-inorganic Cs0.91Rb0.09PbBr3 perovskite solar cell achieved a peak power conversion efficiency of 9.40% under one sun illumination and a maximum voltage of 0.39 V and current of 1.40 µA in a flowing vapor atmosphere.

14.
Dalton Trans ; 52(13): 4038-4043, 2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-36880382

RESUMO

Carbon-based all-inorganic perovskite solar cells have attracted growing interest owing to their simple fabrication process, low cost, and high stability in air. On account of the large interfacial energy barriers and polycrystalline features of perovskite films, the carrier interface recombination and inherent defects in the perovskite layer are still great challenges in further increasing the power conversion efficiency and stability of carbon-based PSCs. We present here a trifunctional polyethylene oxide buffer layer at the perovskite/carbon interface to promote the PCE and stability of carbon-based all-inorganic CsPbBr3 PSCs: (i) the PEO layer increases the crystallinity of inorganic CsPbBr3 grains for low defect state density; (ii) the oxygenic groups in PEO chains passivate the defects on the perovskite surface; and (iii) the long hydrophobic alkyl chains improve the stability in moisture. The best encapsulated PSC achieves a PCE of 8.84% and maintains 84.8% of its initial efficiency in air with 80% RH over 30 days.

15.
Adv Mater ; 35(17): e2211257, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36753745

RESUMO

Metal halide perovskites are promising as next-generation photovoltaic materials, but stability issues are still a huge obstacle to their commercialization. Here, the formation and evolution of cracks in perovskite films during thermal cycling, which affect their mechanical stability, are investigated. Compressive strain is employed to suppress cracks and delamination by in situ formed polymers with low elastic modulus during crystal growth. The resultant devices pass the thermal-cycling qualification (IEC61215:2016), retaining 95% of the initial power conversion efficiency (PCE) and compressive strain after 230 cycles. Meanwhile, the p-i-n devices deliver PCEs of 23.91% (0.0805 cm2 ) and 23.27% (1 cm2 ). The findings shed light on strain engineering with respect to their evolution, which enables mechanically stable perovskite solar cells.

17.
Chin J Nat Med ; 21(1): 36-46, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36641231

RESUMO

Bavachin is a dihydroflavonoid compound isolated from Psoralea corylifolia, and exhibits anti-bacterial, anti-inflammatory, anti-tumor and lipid-lowering activities. Recent attention has gradually drawn on bavachin-induced apoptosis in many human cancer cell lines. However, the anti-cancer effects and related mechanisms in colorectal cancer remain unknown. Here, we investigated the effects of bavachin on colorectal cancer in vivo and in vitro. The results showed that bavachin inhibited the proliferation of human colorectal cancer cells and induce apoptosis. These changes were mediated by activating the MAPK signaling pathway, which significantly up-regulated the expression of Gadd45a. Furthermore, Gadd45a silencing obviously attenuated bavachin-mediated cell apoptosis. Inhibition of the MAPK signaling pathway by JNK/ERK/p38 inhibitors also weakened the up-regulation of Gadd45a by bavachin. The anticancer effect of bavachin was also validated using a mouse xenograft model of human colorectal cancer. In conclusion, these findings suggest that bavachin induces the apoptosis of colorectal cancer cells through activating the MAPK signaling pathway.


Assuntos
Neoplasias Colorretais , Transdução de Sinais , Humanos , Flavonoides/farmacologia , Proteínas/metabolismo , Proteínas/farmacologia , Sistema de Sinalização das MAP Quinases , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/farmacologia
18.
J Biomed Mater Res B Appl Biomater ; 111(5): 1015-1023, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36462186

RESUMO

Nitric oxide (NO) releasing vascular graft is promising due to its merits of thromboembolism reduction and endothelialization promotion. In this study, keratin-based NO donor of S-nitrosated keratin (KSNO) was blended with poly(vinyl alcohol) (PVA) and further crosslinked with sodium trimetaphosphate (STMP) to afford PVA/KSNO biocomposite films. These films could release NO sustainably for up to 10 days, resulting in the promotion of HUVECs growth and the inhibition of HUASMCs growth. In addition, these films displayed good blood compatibility and antibacterial activity. Taken together, these films have potential applications in vascular grafts.


Assuntos
Óxido Nítrico , Álcool de Polivinil , Óxido Nítrico/farmacologia , Álcool de Polivinil/farmacologia , Queratinas/farmacologia , Doadores de Óxido Nítrico , Prótese Vascular
19.
J Mater Chem B ; 10(32): 6158-6170, 2022 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-35904091

RESUMO

Tissue-engineered vascular grafts (TEVGs) provide a new alternative for vascular construction. Nitric oxide (NO) is capable of promoting vascular tissue regeneration and reducing restenosis caused by vascular implantation. Therefore, in situ production of NO by catalytic decomposition of the endogenous donor is a promising strategy to fabricate a TEVG. In this study, poly(ε-caprolactone) (PCL) was first electrospun with keratin (Ker) to afford PCL/Ker mats and then incorporated with Cu(II) ions through multiple interactions. This strategy is very simple, green, and facile. Particularly, the incorporated Cu(II) ions were partially reduced to Cu(I) ions due to the reducibility of keratin. The chelated copper ions were expected to catalyze the generation of NO from endogenous S-nitrosothiol (RSNO). As a result, PCL/Ker-Cu mats selectively accelerated the adhesion, migration, and growth of human umbilical vein endothelial cells (HUVECs), while inhibiting the proliferation of human umbilical artery smooth muscle cells (HUASMCs). Furthermore, these mats exhibited excellent blood compatibility and significant antibacterial activity. Vascular implantation in vivo indicated that the tubular mats could inhibit thrombus formation and retain patency for 3 months after implantation in the rabbit carotid artery. More importantly, vascular remodeling was observed during follow-up, including a complete endothelium and smooth muscle layer. Taken together, the PCL/Ker-Cu mats have great potential application in vascular tissue regeneration.


Assuntos
Prótese Vascular , Queratinas , Animais , Proliferação de Células , Cobre/farmacologia , Proteínas do Citoesqueleto , Células Endoteliais da Veia Umbilical Humana , Humanos , Óxido Nítrico/farmacologia , Poliésteres , Coelhos , Engenharia Tecidual
20.
Mol Neurobiol ; 59(7): 4223-4241, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35499795

RESUMO

In recent years, more and more neurodegenerative diseases, such as ALS, FTLD and AD, have been found to share a common pathological feature, which is the depletion of TDP-43 in the nucleus and the accumulation of TDP-43 in the cytoplasm through hyperphosphorylation, ubiquitination and cleavage. Therefore, this kind of neurodegenerative disease is also called TDP-43 proteinopathy. This suggests that TDP-43 plays a role in the pathogenesis of disease. Current studies show that the pathophysiological mechanism of TDP-43 in neurodegeneration is very complex. In this review, we describe the structure of TDP-43, its main physiological functions, the possible pathogenesis and how TDP-43 provides a new pathway to treat neurodegenerative diseases.


Assuntos
Esclerose Amiotrófica Lateral , Doenças Neurodegenerativas , Proteinopatias TDP-43 , Esclerose Amiotrófica Lateral/metabolismo , Proteínas de Ligação a DNA/metabolismo , Humanos , Proteinopatias TDP-43/metabolismo , Proteinopatias TDP-43/patologia , Ubiquitinação
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