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1.
Langmuir ; 40(17): 9255-9264, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38630628

RESUMO

The solid-state lithium sulfur battery (SSLSB) is an attractive next-generation energy storage system by reason of its remarkably high energy density and safety. However, the SSLSB still faces critical challenges, such as sluggish reaction kinetics, mismatched interface, and undesirable reversible capacity. Herein, a high-performance SSLSB is reported using sulfurized polyacrylonitrile with rich selenium-doped sulfur (Se/S-S@pPAN) as a cathode and poly(ethylene oxide)/Li7La3Zr1.4Ta0.6O12 (PEO-LLZTO) as an electrolyte. The sulfur content of the cathode up to 60.9 wt % can be achieved by dispersing selenium sulfide (SeSx) species in the sulfurized polyacrylonitrile (S@pPAN) skeleton at a molecular level. Selenium as a eutectic accelerator can be uniformly distributed in the composite through the Se-S bond and can accelerate the reaction kinetics. The PEO-LLZTO hybrid solid-state electrolyte (SSE) displays an attractive electrochemical performance and provides an intimate contact with electrodes. At 60 °C, Se/S-S@pPAN delivers an impressive discharge capacity of 1042 mAh g-1 at 0.1C and 445 mAh g-1 at 1C. Additionally, the LiFePO4 cathodes combined with PEO-LLZTO deliver a high reversible capacity (158.9 mAh g-1, 1C) and an ultralong lifespan (a capacity retention of 80%, 1000 cycles) at 1C. The synergetic design of the high-performance sulfur cathode and the organic/inorganic hybrid electrolyte is crucial for enabling the high-performance SSLSB.

2.
Acta Pharmacol Sin ; 45(3): 545-557, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37932403

RESUMO

The matrix glycoprotein thrombospondin-1 (THBS1) modulates nitric oxide (NO) signaling in endothelial cells. A high-salt diet induces deficiencies of NO production and bioavailability, thereby leading to endothelial dysfunction. In this study we investigated the changes of THBS1 expression and its pathological role in the dysfunction of mesenteric artery endothelial cells (MAECs) induced by a high-salt diet. Wild-type rats, and wild-type and Thbs1-/- mice were fed chow containing 8% w/w NaCl for 4 weeks. We showed that a high salt diet significantly increased THBS1 expression and secretion in plasma and MAECs, and damaged endothelium-dependent vasodilation of mesenteric resistance arteries in wild-type animals, but not in Thbs1-/- mice. In rat MAECs, we demonstrated that a high salt environment (10-40 mM) dose-dependently increased THBS1 expression accompanied by suppressed endothelial nitric oxide synthase (eNOS) and phospho-eNOS S1177 production as well as NO release. Blockade of transforming growth factor-ß1 (TGF-ß1) activity by a TGF-ß1 inhibitor SB 431542 reversed THBS1 up-regulation, rescued the eNOS decrease, enhanced phospho-eNOS S1177 expression, and inhibited Smad4 translocation to the nucleus. By conducting dual-luciferase reporter experiments in HEK293T cells, we demonstrated that Smad4, a transcription promoter, upregulated Thbs1 transcription. We conclude that THBS1 contributes to endothelial dysfunction in a high-salt environment and may be a potential target for treatment of high-salt-induced endothelium dysfunction.


Assuntos
Células Endoteliais , Cloreto de Sódio , Humanos , Ratos , Camundongos , Animais , Cloreto de Sódio/metabolismo , Células Endoteliais/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Células HEK293 , Endotélio Vascular/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Vasodilatação , Artérias Mesentéricas , Trombospondinas/metabolismo , Óxido Nítrico/metabolismo
3.
Biomed Chromatogr ; 38(3): e5785, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38014505

RESUMO

The aim of this article is to review the application progress of proteomics technology in brain injury research in recent years, point out the current problems that need to be overcome, and explore the application prospects of proteomics analysis in brain injury. This study also aims to retrieve all literature on brain injury and proteomics and summarize it. Through searching and screening, the widespread application of proteomics technology in the treatment of traumatic brain injury (TBI) and the use of a large number of TBI biomarkers were discovered. The pathways mediated by some biomarkers and the physiological and pathological mechanisms of occurrence were elucidated. The current classification of brain injury is mainly based on subjective evaluation of clinical symptoms, combined with objective imaging. However, its practical value is often limited when applied to prognosis evaluation in brain injury. Proteomics technology can make up for this deficiency and provide a reference for the prevention and treatment of brain injury.


Assuntos
Lesões Encefálicas Traumáticas , Lesões Encefálicas , Humanos , Proteômica/métodos , Lesões Encefálicas/metabolismo , Lesões Encefálicas Traumáticas/metabolismo , Biomarcadores
4.
Int J Mol Sci ; 24(10)2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37240101

RESUMO

Lampriform fishes (Lampriformes), which primarily inhabit deep-sea environments, are large marine fishes varying from the whole-body endothermic opah to the world's longest bony fish-giant oarfish, with species morphologies varying from long and thin to deep and compressed, making them an ideal model for studying the adaptive radiation of teleost fishes. Moreover, this group is important from a phylogenetic perspective owing to their ancient origins among teleosts. However, knowledge about the group is limited, which is, at least partially, due to the dearth of recorded molecular data. This study is the first to analyze the mitochondrial genomes of three lampriform species (Lampris incognitus, Trachipterus ishikawae, and Regalecus russelii) and infer a time-calibrated phylogeny, including 68 species among 29 orders. Our phylomitogenomic analyses support the classification of Lampriformes as monophyletic and sister to Acanthopterygii; hence, addressing the longstanding controversy regarding the phylogenetic status of Lampriformes among teleosts. Comparative mitogenomic analyses indicate that tRNA losses existed in at least five Lampriformes species, which may reveal the mitogenomic structure variation associated with adaptive radiation. However, codon usage in Lampriformes did not change significantly, and it is hypothesized that the nucleus transported the corresponding tRNA, which led to function substitutions. The positive selection analysis revealed that atp8 and cox3 were positively selected in opah, which might have co-evolved with the endothermic trait. This study provides important insights into the systematic taxonomy and adaptive evolution studies of Lampriformes species.


Assuntos
Genoma Mitocondrial , Animais , Filogenia , Peixes/genética , RNA de Transferência/genética
5.
Int J Mol Sci ; 24(7)2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-37047790

RESUMO

Radiation-induced brain injury is a serious complication with complex pathogenesis that may accompany radiotherapy of head and neck tumors. Although studies have shown that calcium (Ca2+) signaling may be involved in the occurrence and development of radiation-induced brain injury, the underlying molecular mechanisms are not well understood. In this study, we used real-time quantitative polymerase chain reaction and Western blotting assays to verify our previous finding using next-generation sequencing that the mRNA and protein expression levels of Orai3 in rat brain microvascular endothelial cells (rBMECs) increased after X-ray irradiation. We next explored the role of Orai3 and Orai3-mediated store-operated Ca2+ entry (SOCE) in radiation-induced brain injury. Primary cultured rBMECs derived from wild-type and Orai3 knockout (Orai3(-/-)) Sprague-Dawley rats were used for in vitro experiments. Orai3-mediated SOCE was significantly increased in rBMECs after X-ray irradiation. However, X-ray irradiation-induced SOCE increase was markedly reduced in Orai3 knockout rBMECs, and the percentage of BTP2 (a nonselective inhibitor of Orai channels)-inhibited SOCE was significantly decreased in Orai3 knockout rBMECs. Functional studies indicated that X-ray irradiation decreased rBMEC proliferation, migration, and tube formation (a model for assessing angiogenesis) but increased rBMEC apoptosis, all of which were ameliorated by BTP2. In addition, occurrences of all four functional deficits were suppressed in X-ray irradiation-exposed rBMECs derived from Orai3(-/-) rats. Cerebrovascular damage caused by whole-brain X-ray irradiation was much less in Orai3(-/-) rats than in wild-type rats. These findings provide evidence that Orai3-mediated SOCE plays an important role in radiation-induced rBMEC damage and brain injury and suggest that Orai3 may warrant development as a potential therapeutic target for reducing or preventing radiation-induced brain injury.


Assuntos
Lesões Encefálicas , Canais de Cálcio , Células Endoteliais , Animais , Ratos , Encéfalo/metabolismo , Cálcio/metabolismo , Canais de Cálcio/genética , Canais de Cálcio/metabolismo , Sinalização do Cálcio , Células Endoteliais/metabolismo , Ratos Sprague-Dawley
6.
Angew Chem Int Ed Engl ; 62(52): e202315564, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-37949835

RESUMO

The fast-charging capability of rechargeable batteries is greatly limited by the sluggish ion transport kinetics in anode materials. Here we develop an iodized polyacrylonitrile (I-PAN) anode that can boost the bulk/interphase lithium (Li)-ion diffusion kinetics and accelerate Li-ion desolvation process to realize high-performance fast-charging Li-ion batteries. The iodine immobilized in I-PAN framework expands ion transport channels, compresses the electric double layer, and changes the inner Helmholtz plane to form LiF/LiI-rich solid electrolyte interphase layer. The dissolved iodine ions in the electrolyte self-induced by the interfacial nucleophilic substitution of PF6 - not only promote the Li-ion desolvation process, but also reuse the plated/dead Li formed on the anode under fast-charging conditions. Consequently, the I-PAN anode exhibits a high capacity of 228.5 mAh g-1 (39 % of capacity at 0.5 A g-1 delivered in 18 seconds) and negligible capacity decay for 10000 cycles at 20 A g-1 . The I-PAN||LiNi0.8 Co0.1 Mn0.1 O2 full cell shows excellent fast-charging performance with attractive capacities and negligible capacity decay for 1000 cycles at extremely high rates of 5 C and 10 C (1 C=180 mA g-1 ). We also demonstrate high-performance fast-charging sodium-ion batteries using I-PAN anodes.

7.
Microvasc Res ; 140: 104306, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34973299

RESUMO

Diabetic foot ulcer is a severe complication of diabetes and is prone to being a chronic non-healing wound. We previously demonstrated that endothelial progenitor cell-derived exosomes, which contain miR-221-3p, alleviate diabetic ulcers. Here, to explore the mechanisms underlying this wound healing, we investigated the potential angiogenic effects of miR-221-3p in vitro using cultured human umbilical vein endothelial cells (HUVECs) and in vivo using a streptozotocin-induced mouse model of diabetes. We found that miR-221-3p promoted HUVEC viability, migration, and capillary-like tube formation. HUVECs cultured in high glucose showed up-regulated expression of homeodomain-interacting protein kinase 2 (HIPK2), a predicted target of miR-221-3p that may decrease angiogenesis. Knockdown of HIPK2 enhanced high glucose-suppressed HUVEC viability, migration, and tube formation, counteracting the effects of high glucose. Using a dual luciferase reporter assay, we found that HIPK2 was indeed a direct target of miR-221-3p. Subcutaneous injection of miR-221-3p agomir into diabetic mice promoted wound healing and suppressed HIPK2 expression in wound margin tissue. These findings indicate that HIPK2, as a direct target of miR-221-3p, contributes to the regulatory role of miR-221-3p in diabetic wound healing and may be a novel therapeutic target for diabetic foot ulcer.


Assuntos
Proteínas de Transporte/metabolismo , Pé Diabético/enzimologia , Células Endoteliais da Veia Umbilical Humana/enzimologia , MicroRNAs/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Cicatrização , Animais , Proteínas de Transporte/genética , Movimento Celular , Células Cultivadas , Pé Diabético/genética , Pé Diabético/patologia , Modelos Animais de Doenças , Regulação Enzimológica da Expressão Gênica , Glucose/toxicidade , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/patologia , Humanos , Masculino , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Neovascularização Fisiológica , Proteínas Serina-Treonina Quinases/genética
8.
Crit Rev Food Sci Nutr ; 62(18): 5029-5055, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33554629

RESUMO

Biodegradable films constructed from food ingredients are being developed for food coating and packaging applications to create more sustainable and environmentally friendly alternatives to plastics and other synthetic film-forming materials. In particular, there is a focus on the creation of active packaging materials from natural ingredients, especially plant-based ones. The film matrix is typically constructed from film-forming food components, such as proteins, polysaccharides and lipids. These matrices can be fortified with active ingredients, such as antioxidants and antimicrobials, so as to enhance their functional properties. Edible active films must be carefully designed to have the required optical, mechanical, barrier, and preservative properties needed for commercial applications. This review focuses on the fabrication, properties, and functional performance of edible films constructed from natural active ingredients. It provides an overview of the type of active ingredients that can be used, how they interact with the film matrix, how they migrate through the films, and how they are released. It also discusses the potential application of these active films for food preservation. Finally, future trends are highlighted and areas where further research are required are discussed.


Assuntos
Anti-Infecciosos , Filmes Comestíveis , Antioxidantes , Embalagem de Alimentos , Conservação de Alimentos
9.
Genomics ; 111(3): 260-266, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30445213

RESUMO

Seahorse is characterized by its male pregnancy and sex-role reversal. To better understand the sexual dimorphism of male and female seahorses based on essential genes, we performed systematic transcriptome studies for both genders. A total of 157,834,590 cleaned reads were obtained and assembled into 129,268 transcripts and 31,764 could be annotated. Results showed that 176 up-regulated and 391 down-regulated transcripts were identified in the male seahorses compared with those in females. Genes involved in sex differentiation, such as dmrt1, sox9, fem1 and vasa, were identified and characterized. Moreover, the essential genes involved in reproductive molecular pathway were identified and analyzed in seahorses. In conclusion, the present study provides an archive for the future systematic research on seahorse sex differentiation.


Assuntos
Gônadas/metabolismo , Diferenciação Sexual , Smegmamorpha/genética , Transcriptoma , Animais , Feminino , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Gônadas/crescimento & desenvolvimento , Masculino , Fatores de Transcrição SOX/genética , Fatores de Transcrição SOX/metabolismo , Smegmamorpha/crescimento & desenvolvimento , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
10.
Adv Mater ; 36(9): e2307786, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37924250

RESUMO

Here, a strategy to strengthen d-p orbital hybridization by fabricating π backbonding in the catalyst for efficient lithium polysulfides (LiPSs) conversion is reported. A special interface structure of RuOx quantum dots (QDs) anchored on graphdiyne (GDY) nanoboxes (RuOx QDs/GDY) is prepared to enable strong Ru-to-alkyne π backdonation, which effectively regulates the d-electron structures of Ru centers to promote the d-p orbital hybridization between the catalyst and LiPSs and significantly boosts the catalytic performance of RuOx QDs/GDY. The strong affinity with Li ions and fast Li-ion diffusion of RuOx QDs/GDY also enable ultrastable Li metal anodes. Thus, S@RuOx QDs/GDY cathodes exhibit excellent cycling performance under harsh conditions, and Li@RuOx QDs/GDY anodes show an ultralong cycling life over 8800 h without Li dendrite growth. Lithium-sulfur (Li-S) full cells with S@RuOx QDs/GDY cathodes and Li@RuOx QDs/GDY anodes can deliver an impressive areal capacity of 17.8 mA h cm-2 and good cycling stability under the practical conditions of low negative-to-positive electrode capacity (N/P) ratio (N/P = 1.4), lean electrolyte (E/S = 3 µL mg-1 ), and high S mass loading (15.4 mg cm-2 ).

11.
Materials (Basel) ; 17(5)2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38473538

RESUMO

To address the issues of insufficient strength and poor precision in polystyrene forming parts during the selective laser sintering process, a ternary composite of polystyrene/glass fiber/hollow glass microbeads was prepared through co-modification by incorporating glass fiber and hollow glass microbeads into polystyrene using a mechanical mixing method. The bending strength and dimensional accuracy of the sintered composites were investigated by conducting an orthogonal test and analysis of variance to study the effects of laser power, scanning speed, scanning spacing, and delamination thickness. The process parameters were optimized and selected to determine the optimal combination. The results demonstrated that when considering bending strength and Z-dimensional accuracy as evaluation criteria for terpolymer sintered parts, the optimum process parameters are as follows: laser power of 24 W, scanning speed of 1600 mm/s, scanning spacing of 0.24 mm, and delamination thickness of 0.22 mm. Under these optimal process parameters, the bending strength of sintered parts reaches 6.12 MPa with a relative error in the Z-dimension of only 0.87%. The bending strength of pure polystyrene sintered parts is enhanced by 15.69% under the same conditions, while the relative error in the Z-dimension is reduced by 63.45%. It improves the forming strength and precision of polystyrene in the selective laser sintering process and achieves the effect of enhancement and modification, which provides a reference and a new direction for exploring polystyrene-based high-performance composites and expands the application scope of selective laser sintering technology.

12.
Materials (Basel) ; 17(5)2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38473608

RESUMO

Porous structures can reduce the elastic modulus of implants, decrease stress shielding, and avoid bone loss in the alveolar bone and aseptic loosening of implants; however, there is a mismatch between yield strength and elastic modulus as well as biocompatibility problems. This study aimed to investigate the parametric design method of porous root-shaped implants to reduce the stress-shielding effect and improve the biocompatibility and long-term stability and effectiveness of the implants. Firstly, the porous structure part was parametrically designed, and the control of porosity gradient distribution was achieved by using the fitting relationship between porosity and bias and the position function of bias. In addition, the optimal distribution law of the porous structure was explored through mechanical and hydrodynamic analyses of the porous structure. Finally, the biomechanical properties were verified using simulated implant-bone tissue interface micromotion values. The results showed that the effects of marginal and central porosity on yield strength were linear, with the elastic modulus decreasing from 18.9 to 10.1 GPa in the range of 20-35% for marginal porosity, with a maximum decrease of 46.6%; the changes in the central porosity had a more consistent effect on the elastic modulus, ranging from 18.9 to 15.3 GPa in the range of 50-90%, with a maximum downward shift of 19%. The central porosity had a more significant effect on permeability, ranging from 1.9 × 10-7 m2 to 4.9 × 10-7 m2 with a maximum enhancement of 61.2%. The analysis showed that the edge structure had a more substantial impact on the mechanical properties. The central structure could increase the permeability more effectively. Hence, the porous structure with reasonable gradient distribution had a better match between mechanical properties and flow properties. The simulated implantation results showed that the porous implant with proper porosity gradient distribution had better biomechanical properties.

13.
J Agric Food Chem ; 71(36): 13325-13337, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37642581

RESUMO

Depression and vulnerability to chronic stress are associated with inflammatory responses and the loss of blood-brain barrier (BBB) integrity. Dietary fiber and its short-chain fatty acid (SCFAs) metabolites have been reported to affect neuropsychiatric disorders. Here, a 9-week treatment course of inulin (0.037 g of inulin/kcal) exhibited in chronic unpredictable mild stress (CUMS) mice led to antidepressant and anxiolytic effects, as well as improved neurogenesis and synaptic plasticity by enhancing CREB/BDNF signaling. Importantly, inulin inhibited CUMS-induced decreased BBB permeability, reduced lipopolysaccharide (LPS) brain penetration, and modulated TLR4/MyD88/NF-κB signaling to alleviate neuroinflammatory responses. Furthermore, inulin protected the gut barrier integrity and led to the increased formation of SCFAs. Enhanced SCFAs formation was strongly positively correlated with behavioral improvements, BBB integrity, and neuroinflammatory responses. We speculate that dietary fiber may be a promising nutritional intervention to reverse the effects of chronic stress by regulating metabolites and protecting the BBB integrity.


Assuntos
Inulina , NF-kappa B , Animais , Camundongos , NF-kappa B/genética , Fator 88 de Diferenciação Mieloide/genética , Receptor 4 Toll-Like/genética , Barreira Hematoencefálica , Proteínas Adaptadoras de Transdução de Sinal , Fibras na Dieta , Inflamação , Permeabilidade
14.
Food Chem ; 426: 136390, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37307740

RESUMO

The production and consumption of functional foods has become an essential food industry trend. Due to its high nutritional content, quinoa is regarded as a super pseudocereal for the development of nutritious foods. However, the presence of antinutritional factors and quinoa's distinctive grassy flavor limit its food applications. Due to its benefits in enhancing the nutritional bioavailability and organoleptic quality of quinoa, germination has garnered significant interest. To date, there is no systematic review of quinoa germination and the health benefits of germinated quinoa. This review details the nutritional components and bioactivities of germinated quinoa, as well as the potential mechanisms for the accumulation of bioactive compounds during the germination process. Additionally, evidence supporting the health benefits of germinated quinoa, the current status of related product development, and perspectives for future research are presented. Thus, our research is likely to provide theoretical support for the use of germinated quinoa resources.


Assuntos
Chenopodium quinoa , Chenopodium quinoa/química , Sementes/química , Alimento Funcional/análise , Manipulação de Alimentos , Valor Nutritivo
15.
JMIR Public Health Surveill ; 9: e46708, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37930785

RESUMO

BACKGROUND: Accurate estimation of incidence and prevalence is vital for preventing and controlling diabetes. Administrative data (including insurance data) could be a good source to estimate the incidence of diabetes. However, how to determine the look-back period (LP) to remove cases with preceding records remains a problem for administrative data. A short LP will cause overestimation of incidence, whereas a long LP will limit the usefulness of a database. Therefore, it is necessary to determine the optimal LP length for identifying incident cases in administrative data. OBJECTIVE: This study aims to offer different methods to identify the optimal LP for diabetes by using medical insurance data from the Chinese population with reference to other diseases in the administrative data. METHODS: Data from the insurance database of the city of Weifang, China from between January 2016 and December 2020 were used. To identify the incident cases in 2020, we removed prevalent patients with preceding records of diabetes between 2016 and 2019 (ie, a 4-year LP). Using this 4-year LP as a reference, consistency examination indexes (CEIs), including positive predictive values, the κ coefficient, and overestimation rate, were calculated to determine the level of agreement between different LPs and an LP of 4 years (the longest LP). Moreover, we constructed a retrograde survival function, in which survival (ie, incident cases) means not having a preceding record at the given time and the survival time is the difference between the date of the last record in 2020 and the most recent previous record in the LP. Based on the survival outcome and survival time, we established the survival function and survival hazard function. When the survival probability, S(t), remains stable, and survival hazard converges to zero, we obtain the optimal LP. Combined with the results of these two methods, we determined the optimal LP for Chinese diabetes patients. RESULTS: The κ agreement was excellent (0.950), with a high positive predictive value (92.2%) and a low overestimation rate (8.4%) after a 2-year LP. As for the retrograde survival function, S(t) dropped rapidly during the first 1-year LP (from 1.00 to 0.11). At a 417-day LP, the hazard function reached approximately zero (ht=0.000459), S(t) remained at 0.10, and at 480 days, the frequency of S(t) did not increase. Combining the two methods, we found that the optimal LP is 2 years for Chinese diabetes patients. CONCLUSIONS: The retrograde survival method and CEIs both showed effectiveness. A 2-year LP should be considered when identifying incident cases of diabetes using insurance data in the Chinese population.


Assuntos
Diabetes Mellitus , Seguro , Humanos , População do Leste Asiático , Estudos Retrospectivos , Diabetes Mellitus/epidemiologia , Povo Asiático
16.
Adv Sci (Weinh) ; 10(31): e2302446, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37767950

RESUMO

Electrochemical oxygen reduction reaction (ORR) is an attractive and alternative route for the on-site production of hydrogen peroxide (H2 O2 ). The electrochemical synthesis of H2 O2 in neutral electrolyte is in early studying stage and promising in ocean-energy application. Herein, N-doped carbon materials (N-Cx ) with different N types are prepared through the pyrolysis of zeolitic imidazolate frameworks. The N-Cx catalysts, especially N-C800 , exhibit an attracting 2e- ORR catalytic activity, corresponding to a high H2 O2 selectivity (≈95%) and preferable stability in 0.5 m NaCl solution. Additionally, the N-C800 possesses an attractive H2 O2 production amount up to 631.2 mmol g-1  h-1 and high Faraday efficiency (79.8%) in H-type cell. The remarkable 2e- ORR electrocatalytic performance of N-Cx catalysts is associated with the N species and N content in the materials. Density functional theory calculations suggest carbon atoms adjacent to graphitic N are the main catalytic sites and exhibit a smaller activation energy, which are more responsible than those in pyridinic N and pyrrolic N doped carbon materials. Furthermore, the N-C800 catalyst demonstrates an effective antibacterial performance for marine bacteria in simulated seawater. This work provides a new insight for electro-generation of H2 O2 in neutral electrolyte and triggers a great promise in ocean-energy application.

17.
Acta Med Okayama ; 66(3): 253-61, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22729106

RESUMO

Cultured Clostridium botulinum strains produce progenitor toxins designated as 12S, 16S, and 19S toxins. The 12S toxin consists of a neurotoxin (NTX, 7S) and a non-toxic non-hemagglutinin (NTNH). The 16S and 19S toxins are formed by conjugation of the 12S toxin with hemagglutinin (HA), and the 19S toxin is a dimer of the 16S toxin. Type A cultures produce all 3 of these progenitor toxins, while type E produces only the 12S toxin. The 7S toxin is cleaved into heavy (H) and light (L) chains by a protease(s) in some strains, and the H chain has 2 domains, the N-terminus (Hn) and C-terminus (Hc). It has been reported that type A toxins bind to the intestinal cells or cultured cells via either HA or Hc. In this study, we investigated the binding of type A and E toxins to Caco-2 cells using Western blot analysis. Both the type E 7S and 12S toxins bound to the cells, with the 7S toxin binding more strongly, whereas, in the type A strain, only the 16S/19S toxins showed obvious binding. Pre-incubation of the type E 7S toxin with IgG against recombinant type E Hc significantly inhibited the 7S toxin binding, indicating that Hc might be a main binding domain of the type E toxin.


Assuntos
Toxinas Botulínicas Tipo A/metabolismo , Toxinas Botulínicas/metabolismo , Western Blotting , Toxinas Botulínicas/isolamento & purificação , Toxinas Botulínicas Tipo A/isolamento & purificação , Células CACO-2 , Humanos
18.
Artigo em Chinês | MEDLINE | ID: mdl-23072136

RESUMO

OBJECTIVE: To investigate the expression and its significance of tumor necrosis factor-alpha (TNF-alpha) and caspase-3 protein in monocytes adjacent to the invaded Echinococcus multilocularis in liver. METHODS: 40 female Kunming mice were randomly divided into experimental group (n=20) and sham operation (control) group (n=20). Mice in experimental group were infected with 20% E. multilocularis suspension (0.1 ml per mouse) through abdominal opening injection in liver and the mice in control group were injected with equal physiological saline. The mice were sacrificed at 6 months post-infection for observing the growth and metastasis of E. multilocularis. Pathological changes were observed by HE staining. The expression of TNF-alpha and caspase-3 protein in hydatid cyst and metastasis tissue were detected by immunohistochemistry staining and the apoptosis of the monocytes was measured by TUNEL. RESULTS: After 6 months post-infection, E. multilocularis were spread over the liver of the mice in experimental group. Metastasis rate of lymph nodes was 45.0% (9/20). Infiltration of monocytes was observed around E. multilocularis in liver and lymph nodes with metastasis by HE staining. Immunohistochemistry showed that the positive expression rate of TNF-alpha and caspase-3 protein in monocytes was 100% and 100%, and 95% and 100% respectively around the cyst in experimental group, while the expression rate was only 5% and 0 respectively in the liver of the control mice (P<0.01). The monocytes showed significant apoptosis by TUNEL in experimental group with a positive expression rate of 100%, with a significant difference between experiment group and the control (P<0.01). CONCLUSION: In the process of alveolar Echinococcus infection, the high expression of TNF-alpha protein might be associated with the apoptosis of monocytes, which may inhibit the host immunological function.


Assuntos
Caspase 3/metabolismo , Equinococose Hepática/patologia , Monócitos/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Animais , Apoptose , Equinococose Hepática/metabolismo , Equinococose Hepática/parasitologia , Echinococcus multilocularis , Feminino , Fígado/parasitologia , Fígado/patologia , Camundongos , Camundongos Endogâmicos , Monócitos/citologia
19.
Innovation (Camb) ; 3(1): 100185, 2022 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-34984407

RESUMO

Few fishes have evolved elevated body temperatures compared with ambient temperatures, and only in opah (Lampris spp) is the entire body affected. To understand the molecular basis of endothermy, we analyzed the opah genome and identified 23 genes with convergent amino acid substitutions across fish, birds, and mammals, including slc8b1, which encodes the mitochondrial Na+/Ca2+ exchanger and is essential for heart function and metabolic heat production. Among endothermic fishes, 44 convergent genes with suggestive metabolic functions were identified, such as glrx3, encoding a crucial protein for hemoglobin maturation. Numerous genes involved in the production and retention of metabolic heat were also found to be under positive selection. Analyses of opah's unique inner-heat-producing pectoral muscle layer (PMI), an evolutionary key innovation, revealed that many proteins were co-opted from dorsal swimming muscles for thermogenesis and oxidative phosphorylation. Thus, the opah genome provides valuable resources and opportunities to uncover the genetic basis of thermal adaptations in fish.

20.
Adv Sci (Weinh) ; 8(15): e2100076, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34047062

RESUMO

Shifting electrochemical oxygen reduction reaction (ORR) via two-electron pathway becomes increasingly crucial as an alternative/green method for hydrogen peroxide (H2 O2 ) generation. Here, the development of 2e- ORR catalysts in recent years is reviewed, in aspects of reaction mechanism exploration, types of high-performance catalysts, factors to influence catalytic performance, and potential applications of 2e- ORR. Based on the previous theoretical and experimental studies, the underlying 2e- ORR catalytic mechanism is firstly unveiled, in aspect of reaction pathway, thermodynamic free energy diagram, limiting potential, and volcano plots. Then, various types of efficient catalysts for producing H2 O2 via 2e- ORR pathway are summarized. Additionally, the catalytic active sites and factors to influence catalysts' performance, such as electronic structure, carbon defect, functional groups (O, N, B, S, F etc.), synergistic effect, and others (pH, pore structure, steric hindrance effect, etc.) are discussed. The H2 O2 electrogeneration via 2e- ORR also has various potential applications in wastewater treatment, disinfection, organics degradation, and energy storage. Finally, potential future directions and prospects in 2e- ORR catalysts for electrochemically producing H2 O2 are examined. These insights may help develop highly active/selective 2e- ORR catalysts and shape the potential application of this electrochemical H2 O2 producing method.

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