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1.
Nanotechnology ; 35(39)2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38959865

RESUMO

Nickel anchored N-doped carbon electrocatalysts (Ni-N-C) are rapidly developed for the electrochemical reduction reaction of carbon dioxide (CO2RR). However, the high-performanced Ni-N-C analogues design for CO2RR remains bewilderment, for the reason lacking of definite guidance for its structure-activity relationship. Herein, the correlation between the proportion of nitrogen species derived from various nitrogen sources and the CO2RR activity of Ni-N-C is investigated. The x-ray photoelectron spectroscopy (XPS) spectrum combined with the CO2RR performance results show that pyridinic-N content has a positive correlation with CO2RR activity. Moreover, density functional theory (DFT) demonstrates that pyridinic-N coordinated Ni-N4sites offers optimized free energy and favorable selectivity towards CO2RR compared with pyrrolic-N. Accordingly, Ni-Na-C with highest pyridinic-N content (ammonia as nitrogen source) performs superior CO2RR activity, with the maximum carbon monoxide faradaic efficiency (FECO) of 99.8% at -0.88 V vs. RHE and the FECOsurpassing 95% within potential ranging of -0.88 to -1.38 V vs. RHE. The building of this parameter for CO2RR activity of Ni-N-C give instructive forecast for low-cost and highly active CO2RR electrocatalysts.

2.
Nanotechnology ; 35(18)2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38262057

RESUMO

Oxygen evolution reaction (OER) plays a key role in electrochemical conversion, which needs efficient and economical electrocatalyst to boost its kinetics for large-scale application. Herein, a bimetallic CoP/FeP2heterostructure with a three-dimensional ordered macroporous structure (3DOM-CoP/FeP2) was synthesized as an OER catalyst to demonstrate a heterogeneous engineering induction strategy. By adjusting the electron distribution and producing a lot of active sites, the heterogeneous interface enhances catalytic performance. High specific surface area is provided by the 3DOM structure. Additionally, at the solid-gas-electrolyte threephase interface, the electrocatalytic reaction exhibits good mass transfer.In situRaman spectroscopy characterization revealed that FeOOH and CoOOH reconstructed from CoP/FeP2were the true OER active sites. Consequently, the 3DOM-CoP/FeP2demonstrates superior OER activity with a low overpotentials of 300/420 mV at 10/100 mA cm-2and meritorious OER durability. It also reveals promising performance as the overall water splitting anode.

3.
J Nanobiotechnology ; 22(1): 96, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38448951

RESUMO

BACKGROUND: Nanoplastics (NPs) are now a new class of pollutants widely present in the soil, atmosphere, freshwater and marine environments. Nanoplastics can rapidly penetrate cell membranes and accumulate in human tissues and organs, thus posing a potential threat to human health. The heart is the main power source of the body. But up to now, the toxicological effects of long-term exposure to nanoplastics on the heart has not been revealed yet. RESULTS: We evaluated the effects of long term exposure of nanoplastics on cardiac cell/tissue in vitro and in vivo model. Furthermore, we explored the molecular mechanism by which nanoplastics exposure causes myocardial cell senescence. Immunohistochemistry, indirect immunofluorescence and ELISA were performed to detect the effects of nanoplastics on heart aging. We found that nanoplastics were able to induce significant cardiac aging through a series of biochemical assays in vivo. In vitro, the effects of nanoplastics on cardiac cell were investigated, and found that nanoplastics were able to internalize into cardiomyocytes in time and dose-dependant manner. Further biochemical analysis showed that nanoplastics induces cardiomyocytes senescence by detecting a series of senescence marker molecules. Molecular mechanism research shows that nanoplastics may cause mitochondrial destabilization by inducing oxidative stress, which leads to the leakage of mtDNA from mitochondria into the cytoplasm, and then cytoplasm-localized mt-DNA activates the cGAS-STING signaling pathway and promotes inflammation response, ultimately inducing cardiomyocytes senescence. CONCLUSIONS: In this work, we found that nanoplastics exposure induces premature aging of heart. Current research also reveals the molecular mechanism by which nanoplastics induces cardiomyocyte senescence. This study laid the foundation for further studying the potential harm of nanoplastics exposure on heart.


Assuntos
DNA Mitocondrial , Miócitos Cardíacos , Humanos , Microplásticos , Senescência Celular , Mitocôndrias , Transdução de Sinais
4.
Small ; 19(47): e2304131, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37486972

RESUMO

As an attractive high-energy-density technology, the practical application of lithium-sulfur (Li-S) batteries is severely limited by the notorious dissolution and shuttle effect of lithium polysulfides (LiPS), resulting in sluggish reaction kinetics and uncontrollable dendritic Li growth. Herein, a p-n typed heterostructure consisting of n-type MoS2 nanoflowers embedded with p-type NiO nanoparticles is designed on carbon nanofibers (denoted as NiO-MoS2 @CNFs) as both cathode sulfur immobilizer and anode Li stabilizer for practical Li-S batteries. Such p-n typed heterostructure is proposed to establish the built-in electric field across the heterointerface for facilitated the positive charge to reach the surface of NiO-MoS2 , meanwhile inherits the excellent LiPS adsorption ability of p-type NiO nanoparticles and catalytic ability of n-type MoS2 . As the anode matrix, the implementation of NiO-MoS2 heterostructure can prevent the growth of Li dendrites by enhancing the lithiophilicity and reducing local current density. The obtained Li-S full battery exhibits an ultra-high areal capacity over 7.3 mAh cm-2 , far exceeding that of current commercial Li-ion batteries. Meanwhile, a stable cycling performance can be achieved under low electrolyte/sulfur ratio of 5.8 µL mg-1 and negative/positive capacity ratio of 1. The corresponding pouch cell maintains high energy density of 305 Wh kg-1 and stable cycling performance under various bending angles.

5.
BMC Pregnancy Childbirth ; 22(1): 290, 2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-35387646

RESUMO

BACKGROUND: To examine the association of hemoglobin (Hb) levels during gestation with the risk of selected adverse pregnancy outcomes such as preterm birth (PTB), low-birth-weight infants (LBW) and small-for-gestational-age infants (SGA) in Chinese women. METHODS: This retrospective cohort study was conducted in the Department of Gynecology and Obstetrics at the Union Shenzhen Hospital of the Huazhong University of Science and Technology, using routinely collected maternity and hospital data on pregnancies (2015-2018). Hb levels were measured during the second (16-18th weeks) and third (28-30th weeks) trimesters of pregnancy, and pregnancy outcomes were recorded in the hospital information system. Hb levels were categorized into four groups as follows: < 110 g/L, 110-119 g/L, 120-130 g/L, and > 130 g/L. The second group (Hb 110-119 g/L) was defined as the reference group. Statistical analysis was performed using multivariate logistic regression. RESULTS: A total of 1911 singleton mothers were included. After multivariable adjustment, Hb levels > 130 g/L in the second trimester increased the risk of LBW (odds ratio [OR], 2.54; 95% confidence interval [CI], 1.12-5.76). In the third trimester of gestation, compared with women whose Hb levels between 110 and 119 g/L, women with Hb levels > 130 g/L had an increased risk of LBW (OR, 2.20; 95% CI, 1.07-4.51) and SGA (OR, 2.00; 95% CI, 1.05-3.80). When we compared the highest and lowest quartiles of changes in the Hb across the second and third trimesters, the adjusted ORs were 0.35 (95% CI: 0.18-0.68) for PTB and 0.47 (95% CI: 0.23-0.98) for LBW. CONCLUSION: Maternal Hb > 130 g/L was associated with increased risk of adverse pregnancy outcomes. Reduction of the risks of PTB and SGA were observed with the appropriate increase of Hb level during the third trimester.


Assuntos
Nascimento Prematuro , China/epidemiologia , Feminino , Hemoglobinas/análise , Humanos , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional , Gravidez , Resultado da Gravidez/epidemiologia , Nascimento Prematuro/epidemiologia , Estudos Retrospectivos , Fatores de Risco
6.
Reprod Health ; 19(1): 192, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36109752

RESUMO

BACKGROUND: In recent years, results on the association between serum uric acid (UA) and pregnancy outcomes have been inconsistent, and the association between urea nitrogen (UN) and adverse pregnancy outcomes in normal pregnant women has not been reported. Thus, we examined the association of UA and UN levels during gestation with the risk of adverse pregnancy outcomes in a relatively large population. METHODS: A total of 1602 singleton mothers from Union Shenzhen Hospital of Huazhong University of Science and Technology at January 2015 to December 2018 were included. Both UA and UN levels were collected and measured during the second (16-18th week) and third (28-30th week) trimesters of gestation respectively. Statistical analysis was performed using multivariate logistic regression. RESULTS: After adjustment, the highest quartile of UA in the third trimester increased the risk of premature rupture of membranes (PROM) and small for gestational age infants (SGA) by 48% (odds ratio [OR]: 1.48, 95% confidence interval [CI]: 1.04-2.10) and 99% (95% CI: 1.01-3.89) compared to those in the lowest quartile. The adjusted OR (95% CI) in the highest quartile of UN for the risk of SGA was 2.18 (95% CI: 1.16-4.13) and 2.29 (95% CI: 1.20-4.36) in the second and third trimester, respectively. In the second trimester, when UA and UN levels were both in the highest quartile, the adjusted OR (95% CI) for the risk of SGA was 2.51 (95% CI: 1.23-5.10). In the third trimester, when the group 1 (both indicators are in the first quartile) was compared, the adjusted ORs (95% CI) for the risk of SGA were 1.98 (95% CI: 1.22-3.23) and 2.31 (95% CI: 1.16-4.61) for group 2 (UA or UN is in the second or third quartile) and group 3 (both indicators are in the fourth quartile), respectively. CONCLUSIONS: Higher UA and UN levels increased the risk of maternal and fetal outcomes. The simultaneous elevation of UA and UN levels was a high-risk factors for the development of SGA, regardless of whether they were in the second or third trimester.


Adverse pregnancy outcomes are important public health problems in terms of high mortality and long-term health effects of maternal and newborn babies. This study assessed the association between serum urea acid and urea nitrogen levels during pregnancy and the risk of adverse pregnancy outcomes in Chinese women. The study was conducted between January 2015 and December 2018. Serum uric acid and urea nitrogen were measured at weeks 16­18 and 28­30, respectively. A total of 1602 singleton pregnant women participated in the study. We found that elevated levels of uric acid and urea nitrogen increased the risk of maternal and infant outcomes. In addition, we found for the first time that elevated uric acid and urea nitrogen concentrations were a risk factor for SGA, both in the second and third trimesters. Therefore, monitoring maternal uric acid and urea nitrogen biochemical parameters during pregnancy is necessary to optimize nursing and intervention. Furthermore, uric acid and urea nitrogen are simple, inexpensive, and readily available tests and should be evaluated additionally.


Assuntos
Ruptura Prematura de Membranas Fetais , Ácido Úrico , Feminino , Ruptura Prematura de Membranas Fetais/epidemiologia , Humanos , Nitrogênio , Gravidez , Resultado da Gravidez , Estudos Retrospectivos , Fatores de Risco , Ureia
7.
BMC Bioinformatics ; 22(1): 326, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34130622

RESUMO

BACKGROUND: With the development of high-throughput sequencing technology, a huge amount of multi-omics data has been accumulated. Although there are many software tools for statistical analysis and visual development of omics data, these tools are not suitable for private data and non-technical users. Besides, most of these tools have specialized in only one or perhaps a few data typesare, without combining clinical information. What's more, users could not choose data processing and model selection flexibly when using these tools. RESULTS: To help non-technical users to understand and analyze private multi-omics data and ensure data security, we developed an interactive desk tool for statistical analysis and visualization of omics and clinical data (shortly IOAT). Our mainly targets csv format data, and combines clinical data with high-dimensional multi-omics data. It also contains various operations, such as data preprocessing, feature selection, risk assessment, clustering, and survival analysis. By using this tool, users can safely and conveniently try a combination of various methods on their private multi-omics data to find a model suitable for their data, conduct risk assessment and determine their cancer subtypes. At the same time, the tool can also provide them with references to genes that are closely related to tumor staging, facilitating the development of precision oncology. We review IOAT's main features and demonstrate its analysis capabilities on a lung from TCGA. CONCLUSIONS: IOAT is a local desktop tool, which provides a set of multi-omics data integration solutions. It can quickly perform a complete analysis of cancer genome data for subtype discovery and biomarker identification without security issues and writing any code. Thus, our tool can enable cancer biologists and biomedicine researchers to analyze their data more easily and safely. IOAT can be downloaded for free from https://github.com/WlSunshine/IOAT-software .


Assuntos
Neoplasias , Análise por Conglomerados , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Neoplasias/genética , Medicina de Precisão , Software
8.
J Org Chem ; 86(12): 8351-8364, 2021 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-34043350

RESUMO

Tetrathiatriarylmethyl (trityl) radicals have been recently shown to react with biological oxidoreductants including glutathione (GSH), ascorbic acid (Asc), and superoxide anion radical (O2•-). However, how the substituents affect the reactivity of trityl radicals is still unknown. In this work, five asymmetric trityl radicals were synthesized and their reactivities with GSH, Asc, and O2•- investigated. Under aerobic conditions, GSH induces fast decays for the thioether- (TSA) and N-methyleneglycine-substituted (TGA) derivatives and slow decay for the 4-carboxyphenyl-containing one (TPA). Under anaerobic conditions, the direct reduction of these radicals by GSH also occurs with rate constants (kGSH) from 1.8 × 10-4 M-1 s-1 for TPA to 1.0 × 10-2 M-1 s-1 for TGA. Moreover, these radicals can also react with O2•- with rate constants (kSO) from 1.2 × 103 M-1 s-1 for ET-01 to 1.6 × 104 M-1 s-1 for TGA. Surprisingly, these radicals are completely inert to Asc in both aerobic and anaerobic conditions. Additionally, the substituents exert an important effect on redox potentials of these trityl radicals. This work demonstrates that the redox properties of the trityl radicals strongly depend on their substituents, and TPA with high stability toward GSH shows great potential for intracellular applications.


Assuntos
Compostos de Tritil , Água , Espectroscopia de Ressonância de Spin Eletrônica , Radicais Livres , Oxirredução
9.
Pharm Biol ; 59(1): 912-921, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34236293

RESUMO

CONTEXT: Valeriana jatamansi Jones [syn. V. wallichii DC, (Valerianaceae)] (VJJ) is used to treat depression. OBJECTIVE: To explore the effects of total iridoids of VJJ extract (TIV) on chronic unpredictable mild stress (CUMS) in mice. MATERIALS AND METHODS: VJJ roots and rhizomes were extracted with 70% ethanol. CUMS rats were treated daily with fluoxetine (2.6 mg/kg, i.g.) or TIV (5.7, 11.4, and 22.8 mg/kg, i.g.) for 14 days. Male Kun Ming mice on normal chow and 0.5% CMC-Na solution were used as a control. Behavioural tests included the tail suspension (TST) and sucrose preference tests (SPT). Evans blue staining was used to evaluate blood-brain barrier (BBB) permeability. Western blotting was used to measure zonula occludens-1 (ZO-1) and occludin expression. 16S rRNA sequencing was used to analyse intestinal flora abundance. Tax4Fun was used to predict KEGG metabolic pathways. RESULTS: TIV treatment reduced TST time (117.35 ± 8.23 or 108.95 ± 6.76 vs. 144.45 ± 10.30 s), increased SPT (55.83 ± 7.24 or 53.12 ± 13.85 vs. 38.98 ± 5.43%), increased the abundance of phylum Firmicutes (86.99 ± 0.03 vs. 60.88 ± 0.19%) and genus Lactobacillus (75.20 ± 0.19 vs. 62.10 ± 0.13%), reduced the abundance of phylum Bacteroidetes (6.69 ± 0.06 or 11.50 ± 0.09 vs. 25.07 ± 0.20%). TIV increased carbohydrate metabolism (14.50 ± 3.00 × 10-3 or 14.60 ± 2.00 × 10-3 or 14.90 ± 2.00 × 10-3 vs.13.80 ± 4.00 × 10-3%), replication and repair functions (5.60 ± 1.00 × 10-3 or 5.60 ± 1.00 × 10-3 vs. 5.10 ± 4.00 × 10-3%), reduced the frequency of infectious disease (1.60 ± 2.00 × 10-4 or 1.90 ± 5.00 × 10-4 or 1.80 ± 3.00 × 10-4 vs. 2.20 ± 7.00 × 10-3%), BBB permeability (0.77 ± 0.30 vs. 1.81 ± 0.33 µg/g), and up-regulated the expression of ZO-1 (1.42-fold, 1.60-fold, 1.71-fold) and occludin (1.79-fold, 2.20-fold). CONCLUSIONS: TIV may modulate the intestinal flora, thereby inducing the expression of ZO-1 and occludin, protecting the BBB and exerting an antidepressant effect.


Assuntos
Antidepressivos/farmacologia , Iridoides/farmacologia , Extratos Vegetais/farmacologia , Estresse Psicológico/tratamento farmacológico , Animais , Animais não Endogâmicos , Antidepressivos/administração & dosagem , Antidepressivos/isolamento & purificação , Barreira Hematoencefálica/metabolismo , Depressão/tratamento farmacológico , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Fluoxetina/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Iridoides/administração & dosagem , Iridoides/isolamento & purificação , Masculino , Camundongos , Ocludina/genética , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Ratos , Regulação para Cima/efeitos dos fármacos , Valeriana/química , Proteína da Zônula de Oclusão-1/genética
10.
Planta Med ; 86(3): 172-179, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31801162

RESUMO

Valeriana jatamansi is widely used in Chinese folk medicine and contains iridoids as important active ingredients. The brain-gut axis describes a complex bidirectional system between the central nervous system and the gastrointestinal tract. Herein, we evaluated the antidepressant effects of total iridoids of Valeriana jatamansi (TIV) and preliminarily investigated the effects of gut microbiota on their antidepressant effects using a chronic, unpredictable mild-stress mouse model. Mice were given 5.7, 11.4, or 22.9 mg/kg TIV for 1 week. Fluoxetine (2.6 mg/kg) served as a positive control. Body weight was measured, and behavioral tests including SPT and TST were applied. Colon pathology was assessed through hematoxylin-eosin staining. Additionally, levels of serotonin (5-hydroxytryptamine, 5-HT), norepinephrine (NE), substance P (SP) and corticotropin-releasing factor (CRF) in the hippocampus and colon were measured by ELISA. In addition, 16SrRNA gene sequencing was performed to explore changes in intestinal microbiota richness and diversity. Our results demonstrated that the model group showed significant depression-like behavior, while the fluoxetine group showed improved depression-like symptoms; after administration, TIV increased body weight, sucrose solution consumption, and ameliorated depression-like behaviors. The overall cell degeneration in colons also improved. In addition, TIV modulated the levels of 5-HT, NE, SP, and CRF expression in the hippocampus and colon. The diversity and richness of gut microbes increased compared to the model group. We therefore conclude that the antidepressant effects of TIV may be related to gut flora structures and regulation of 5-HT, NE, SP, and CRF in the brain and intestine.


Assuntos
Trato Gastrointestinal , Valeriana , Animais , Antidepressivos , Comportamento Animal , Encéfalo , Modelos Animais de Doenças , Hipocampo , Intestinos , Iridoides , Camundongos , Estresse Psicológico
11.
J Cell Physiol ; 234(10): 18513-18523, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30912144

RESUMO

Cytoskeleton which includes microtubule and actin filaments plays important roles during mammalian oocyte maturation. In the present study, we showed that protein kinase C mu (PKC mu) was one potential key molecule which affected cytoskeleton dynamics in mouse oocytes. Our results showed that PKC mu expressed and localized at the poles of the spindle during oocyte maturation, and PKC mu expression reduced in the oocytes from 6-month-old mice or 24 hr in vitro culture. We knocked down the expression of PKC mu in oocytes using morpholino injection to explore the relationship between PKC mu and subcellular structure defects. The loss of PKC mu reduced oocyte maturation competence, showing with decreased polar body extrusion rate and increased rate of symmetric division. Further analysis indicated that PKC mu decrease caused the spindle organization defects, and this could be confirmed by the decreased tubulin acetylation level. Moreover, we found that PKC mu affected the phosphorylation level of cofilin for actin assembly, which further affected cytoplasmic actin distribution and spindle positioning. In summary, our data indicated that PKC mu is one key factor for oocyte maturation through its roles on the spindle organization and actin filament distribution.


Assuntos
Citoesqueleto/metabolismo , Meiose , Oócitos/citologia , Oócitos/metabolismo , Proteína Quinase C/metabolismo , Acetilação , Fatores de Despolimerização de Actina/metabolismo , Actinas/metabolismo , Animais , Diferenciação Celular , Feminino , Camundongos Endogâmicos ICR , Fosforilação , Corpos Polares/metabolismo , Fuso Acromático , Tubulina (Proteína)/metabolismo
12.
Toxicol Appl Pharmacol ; 370: 44-55, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30880215

RESUMO

Development of atherosclerosis involves chronic and sustained inflammation and oxidative stress. Recent studies have linked atherosclerosis to the innate immune system. Genetic deficiency in myeloid differentiation primary-response protein 88 (MyD88) protects against the development and progression of atherosclerosis. However, it is unknown if pharmacological inhibition of MyD88 is able to be a therapeutic strategy for this disease. In this study, we evaluated the effect of a newly synthesized small-molecule inhibitor of MyD88, LM9, in an ApoE-/- mouse model of atherosclerosis. Our results showed that the major source of MyD88 in atherosclerotic lesions is infiltrated macrophage. Treatment of HFD-fed ApoE-/- mice with LM9 significantly attenuated the pathogenesis of atherosclerosis, accompanied with reduced vascular inflammatory responses and oxidative stress. These effects were achieved without changes to serum lipid levels. We further showed that LM9 inhibited oxidized-lipoprotein induced foam cell formation through suppression of MyD88 and inflammatory pathway in macrophages. Additionally, either LM9 treatment or MyD88 knockdown prevented ox-LDL-induced oxidative stress in macrophages. This study highlights the translational role of MyD88 as a therapeutic target and identifies the MyD88 inhibitor LM9 as a new candidate for the treatment of atherosclerosis.


Assuntos
Aterosclerose/prevenção & controle , Fator 88 de Diferenciação Mieloide/antagonistas & inibidores , Piperazinas/farmacologia , Tiazóis/farmacologia , Animais , Apolipoproteínas E/deficiência , Apolipoproteínas E/genética , Aterosclerose/etiologia , Dieta Hiperlipídica , Modelos Animais de Doenças , Técnicas de Silenciamento de Genes , Lipoproteínas LDL/metabolismo , Lipoproteínas LDL/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Células RAW 264.7 , Espécies Reativas de Oxigênio/metabolismo
13.
Angew Chem Int Ed Engl ; 58(30): 10204-10208, 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31127675

RESUMO

Bipolar redox organics have attracted interest as electrode materials for energy storage owing to their flexibility, sustainability and environmental friendliness. However, an understanding of their application in all-organic batteries, let alone dual-ion batteries (DIBs), is in its infancy. Herein, we propose a strategy to screen a variety of phthalocyanine-based bipolar organics. The self-polymerizable bipolar Cu tetraaminephthalocyanine (CuTAPc) shows multifunctional applications in various energy storage systems, including lithium-based DIBs using CuTAPc as the cathode material, graphite-based DIBs using CuTAPc as the anode material and symmetric DIBs using CuTAPc as both the cathode and anode materials. Notably, in lithium-based DIBs, the use of CuTAPc as the cathode material results in a high discharge capacity of 236 mAh g-1 at 50 mA g-1 and a high reversible capacity of 74.3 mAh g-1 after 4000 cycles at 4 A g-1 . Most importantly, a high energy density of 239 Wh kg-1 and power density of 11.5 kW kg-1 can be obtained in all-organic symmetric DIBs.

14.
J Cell Physiol ; 233(8): 6088-6097, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29319181

RESUMO

LIM kinases (LIMK1/2) are LIM domain-containing serine/threonine/tyrosine kinases that mediate multiple cellular processes in mitosis. In the present study, we explored the functional roles and potential signaling pathway of LIMK1/2 during mouse oocyte meiosis. Disruption of LIMK1/2 activity and expression significantly decreased oocyte polar body extrusion. Live-cell imaging revealed that spindle migration was disturbed after both LIMK1 and LIMK2 knock down, and this might be due to aberrant distribution of actin filaments in the oocyte cytoplasm and cortex. Meanwhile, our results demonstrated that the function of LIMK1 and LIMK2 in actin assembly was related to cofilin phosphorylation levels. In addition, disruption of LIMK1/2 activity significantly increased the percentage of oocytes with abnormal spindle morphologies, which was confirmed by the abnormal p-MAPK localization. We further, explored the upstream molecules of LIMK1/2, and we found that after depletion of ROCK, phosphorylation of LIMK1/2 and cofilin were significantly decreased. Moreover, RhoA inhibition caused the decreased expression of ROCK, p-LIMK1/2, and cofilin. In summary, our results indicated that the small GTPase RhoA regulated LIMK1/2-cofilin to modulate cytoskeletal dynamics during mouse oocyte meiosis.


Assuntos
Fatores de Despolimerização de Actina/metabolismo , Quinases Lim/metabolismo , Meiose/fisiologia , Oócitos/metabolismo , Quinases Associadas a rho/metabolismo , Actinas/metabolismo , Animais , Citoplasma/metabolismo , Camundongos , Camundongos Endogâmicos ICR , Proteínas dos Microfilamentos/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Mitose/fisiologia , Fosforilação/fisiologia , Corpos Polares/metabolismo , Transdução de Sinais/fisiologia , Fuso Acromático/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo
15.
Small ; 14(20): e1704035, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29665268

RESUMO

Metal-organic frameworks (MOFs) with tunable compositions and morphologies are recognized as efficient self-sacrificial templates to achieve function-oriented nanostructured materials. Moreover, it is urgently needed to develop highly efficient noble metal-free oxygen evolution reaction (OER) electrocatalysts to accelerate the development of overall water splitting green energy conversion systems. Herein, a facile and cost-efficient strategy to synthesize Co9 S8 nanoparticles-embedded N/S-codoped carbon nanofibers (Co9 S8 /NSCNFs) as highly active OER catalyst is developed. The hybrid precursor of core-shell ZIF-wrapped CdS nanowires is first prepared and then leads to the formation of uniformly dispersed Co9 S8 /N, S-codoped carbon nanocomposites through a one-step calcination reaction. The optimal Co9 S8 /NSCNFs-850 is demonstrated to possess excellent electrocatalytic performance for OER in 1.0 m KOH solution, affording a low overpotential of 302 mV to reach the current density of 10 mA cm-2 , a small Tafel slope of 54 mV dec-1 , and superior long-term stability for 1000 cyclic voltammetry cycles. The favorable results raise a concept of exploring more MOF-based nanohybrids as precursors to induce the synthesis of novel porous nanomaterials as non-noble-metal electrocatalysts for sustainable energy conversion.

16.
Z Gastroenterol ; 56(2): 111-116, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29113005

RESUMO

BACKGROUND: Peroral endoscopic myotomy (POEM), first introduced in 2010, appears to be an effective therapy with few complications. This study aimed to find an optimal predictor of POEM outcome in achalasia. METHODS: We retrospectively assessed 89 patients diagnosed with achalasia who underwent POEM in General Hospital of Tianjin Medical University, from September 2012 to March 2015. Associations of Eckardt score with symptom duration, lower esophageal resting pressure, 4-second integrated relaxation pressure (4s-IRP), and maximum esophageal diameter were assessed before POEM. The most relevant data were progressively grouped to compare symptom improvement after POEM in 85 patients at 1 year follow-up. RESULTS: The most significant correlation was found between 4s-IRP and Eckardt score (p < 0.01). The 85 achalasia patients (1-year follow-up after POEM) were divided into 3 groups according to 4s-IRP values; patients with mean 4s-IRP of 25 - 34 mmHg exhibited significantly greater improvement of clinical symptoms compared with the remaining 2 groups (p < 0.05). No significant postoperative difference was noted between types I and II in all patients according to Chicago classification criteria. The 40 patients with 4s-IRP of 25 - 34 mmHg were further divided into 2 subgroups; the 28 patients with type II achalasia responded better to POEM than the 12 with type I disease (p < 0.05). CONCLUSIONS: 4s-IRP, together with achalasia subtypes, may predict treatment outcome after POEM. Patients with type II achalasia and 4s-IRP of 25 - 34 mmHg may experience more satisfactory remission after POEM.


Assuntos
Acalasia Esofágica/cirurgia , Esfíncter Esofágico Inferior/cirurgia , Esofagoscopia/métodos , Miotomia , Cirurgia Endoscópica por Orifício Natural/métodos , Acalasia Esofágica/diagnóstico , Acalasia Esofágica/fisiopatologia , Esfíncter Esofágico Inferior/fisiopatologia , Feminino , Humanos , Masculino , Manometria/métodos , Relaxamento Muscular/fisiologia , Pressão , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
17.
Int J Mol Sci ; 19(3)2018 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-29495594

RESUMO

ß-fructofuranosidase (ß-FFase) belongs to the glycosyl-hydrolase family 32 (GH32), which can catalyze both the release of ß-fructose from ß-d-fructofuranoside substrates to hydrolyze sucrose and the synthesis of short-chain fructooligosaccharide (FOS). BmSuc1 has been cloned and identified from the silkworm Bombyx mori as a first animal type of ß-FFase encoding gene. It was hypothesized that BmSUC1 plays an important role in the silkworm-mulberry adaptation system. However, there is little information about the enzymatic core sites of BmSUC1. In this study, we mutated three amino acid residues (D63, D181, and E234) that represent important conserved motifs for ß-FFase activity in GH32 to alanine respectively by using site-directed mutagenesis. Recombinant proteins of three mutants and wild type BmSUC1 were obtained by using a Bac-to-Bac/BmNPV expression system and BmN cells. Enzymatic activity, kinetic properties, and substrate specificity of the four proteins were analyzed. High Performance Liquid Chromatography (HPLC) was used to compare the hydrolyzing and transfructosylating activities between D181A and wtBmSUC1. Our results revealed that the D63A and E234A mutations lost activity, suggesting that D63 and E234 are key amino acid residues for BmSUC1 to function as an enzyme. The D181A mutation significantly enhanced both hydrolyzing and transfructosylating activities of BmSUC1, indicating that D181 may not be directly involved in catalyzation. The results provide insight into the chemical catalyzation mechanism of BmSUC1 in B. mori. Up-regulated transfructosylating activity of BmSUC1 could provide new ideas for using B. mori ß-FFase to produce functional FOS.


Assuntos
Substituição de Aminoácidos , Bombyx/enzimologia , Bombyx/genética , Códon , Mutagênese Sítio-Dirigida , beta-Frutofuranosidase/genética , beta-Frutofuranosidase/metabolismo , Motivos de Aminoácidos , Sequência de Aminoácidos , Animais , Catálise , Sequência Conservada , Ativação Enzimática , Hidrólise , Ligação Proteica , Especificidade por Substrato , beta-Frutofuranosidase/química
18.
Molecules ; 23(3)2018 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-29510477

RESUMO

The pulsed electric fields (PEF) treatment is a novel method for obtaining glycated proteins by way of a Maillard reaction between proteins and polysaccharides but its effect on the preparation of protein-monosaccharide conjugate has not been explored. This study aimed to prepare bovine serum albumin (BSA)-glucose and BSA-mannose conjugates using PEF in pH 10.0 at an intensity of 10 or 20 kV/cm, frequency of 1 kHz, pulse width of 20 µs and 73.5 pulses. The conjugates were evaluated for physicochemical properties. The results indicated that PEF not only promoted Maillard reaction between BSA and glucose or mannose but also alleviated the undesirable browning. PEF treatment favored the increased surface hydrophobicity and emulsifying activity in BSA but reduced surface hydrophobicity and foaming stability and improved foaming capacity in BSA-glucose and BSA-mannose conjugates. These findings provided useful considerations in the application of PEF treatment as a potential method to prepare BSA-monosaccharide conjugates by Maillard reaction.


Assuntos
Glucose/química , Manose/química , Soroalbumina Bovina/química , Albumina Sérica/química , Eletricidade , Interações Hidrofóbicas e Hidrofílicas , Reação de Maillard
19.
Small ; 13(17)2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28244189

RESUMO

Metal-organic frameworks (MOFs) featuring versatile topological architectures are considered to be efficient self-sacrificial templates to achieve mesoporous nanostructured materials. A facile and cost-efficient strategy is developed to scalably fabricate binary metal oxides with complex hollow interior structures and tunable compositions. Bimetal-organic frameworks of Ni-Co-BTC solid microspheres with diverse Ni/Co ratios are readily prepared by solvothermal method to induce the Ni x Co3-x O4 multishelled hollow microspheres through a morphology-inherited annealing treatment. The obtained mixed metal oxides are demonstrated to be composed of nanometer-sized subunits in the shells and large void spaces left between adjacent shells. When evaluated as anode materials for lithium-ion batteries, Ni x Co3-x O4 -0.1 multishelled hollow microspheres deliver a high reversible capacity of 1109.8 mAh g-1 after 100 cycles at a current density of 100 mA g-1 with an excellent high-rate capability. Appropriate capacities of 832 and 673 mAh g-1 could also be retained after 300 cycles at large currents of 1 and 2 A g-1 , respectively. These prominent electrochemical properties raise a concept of synthesizing MOFs-derived mixed metal oxides with multishelled hollow structures for progressive lithium-ion batteries.

20.
Chemistry ; 22(2): 477-80, 2016 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-26555340

RESUMO

Mercury(II) ions have emerged as a widespread environmental hazard in recent decades. Despite different kinds of detection methods reported to sense Hg(2+) , it still remains a challenging task to develop new sensing molecules to replenish the fluorescence-based apparatus for Hg(2+) detection. This communication demonstrates a novel fluorescent sensor using UiO-66-NH2 and a T-rich FAM-labeled ssDNA as a hybrid system to detect Hg(2+) sensitively and selectively. To the best of our knowledge, it has rarely been reported that a MOF is utilized as the biosensing platform for Hg(2+) assay.


Assuntos
Técnicas Biossensoriais/métodos , DNA de Cadeia Simples/química , DNA/química , Íons/química , Mercúrio/análise , Mercúrio/química , Limite de Detecção
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