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1.
Acta Pharmacol Sin ; 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38992119

RESUMO

The escalating obesity epidemic and aging population have propelled metabolic dysfunction-associated steatohepatitis (MASH) to the forefront of public health concerns. The activation of FXR shows promise to combat MASH and its detrimental consequences. However, the specific alterations within the MASH-related transcriptional network remain elusive, hindering the development of more precise and effective therapeutic strategies. Through a comprehensive analysis of liver RNA-seq data from human and mouse MASH samples, we identified central perturbations within the MASH-associated transcriptional network, including disrupted cellular metabolism and mitochondrial function, decreased tissue repair capability, and increased inflammation and fibrosis. By employing integrated transcriptome profiling of diverse FXR agonists-treated mice, FXR liver-specific knockout mice, and open-source human datasets, we determined that hepatic FXR activation effectively ameliorated MASH by reversing the dysregulated metabolic and inflammatory networks implicated in MASH pathogenesis. This mitigation encompassed resolving fibrosis and reducing immune infiltration. By understanding the core regulatory network of FXR, which is directly correlated with disease severity and treatment response, we identified approximately one-third of the patients who could potentially benefit from FXR agonist therapy. A similar analysis involving intestinal RNA-seq data from FXR agonists-treated mice and FXR intestine-specific knockout mice revealed that intestinal FXR activation attenuates intestinal inflammation, and has promise in attenuating hepatic inflammation and fibrosis. Collectively, our study uncovers the intricate pathophysiological features of MASH at a transcriptional level and highlights the complex interplay between FXR activation and both MASH progression and regression. These findings contribute to precise drug development, utilization, and efficacy evaluation, ultimately aiming to improve patient outcomes.

2.
Asian J Surg ; 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39009485

RESUMO

Stapled hemorrhoidopexy has been used for years to treat hemorrhoids. Despite numerous systematic reviews and meta-analyses on the topic, inconsistent conclusions have left people uncertain about its effectiveness and raised doubts about the quality of these reviews.In order to provide reliable evidence for clinical practice, it is crucial to conduct an overview to assess the quality of MAs/SRs regarding the efficacy and complications of SH.A comprehensive search was performed across seven databases to identify MAs/SRs on the efficacy and complications of SH from inception to October 2023. The selected MAs/SRs were then assessed using three well-established tools: AMSTAR-2, PRISMA 2020and GRADE. These assessments provide a robust evaluation of the quality and reliability of the included MAs/SRs.We removed overlapping randomized controlled trials (RCTs) and conducted a new meta-analysis of the outcomes. The overview included 23 meta-analyses.In AMSTAR-2, three reviews were deemed moderate quality, nine reviews were classified as low quality, and eleven reviews were evaluated as critically low quality.In PRISMA 2020,certain deficiencies were exhibited, such as abstracts (0/23:0 %),final retrieval date (0/23:0 %), sensitivity analysis (6/23:26.09 %),publication bias assessment (11/23:47.83 %), the quality of evidence (2/23:8.70 %) and so on.In GRADE,twenty-six items were rated as moderate quality (27.96 %),forty-one items were rated as low quality (44.09 %) and twenty-six items were rated as critically low quality (27.96 %).SH has been found to be an effective intervention for reducing postoperative pain, shortening procedure time, and promoting wound healing. The re-analysis indicated that SH can reduce postoperative pain in hemorrhoid patients (odds ratio = 0.28, 95 % confidence interval [0.15,0.55], p = 0.0002; I2 = 74 %, p < 0.00001). But SH is associated with a higher risk of postoperative bleeding and recurrence of prolapse.Given that the reviews included in this overview were rated as low quality, caution should be exercised when interpreting the findings.

3.
PhytoKeys ; 242: 281-291, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38863649

RESUMO

Based on both morphological and molecular evidence, it is confirmed that Alseodaphnopsismaguanensis is conspecific with A.hokouensis. Hence, Alseodaphnopsismaguanensis is treated as a synonym of A.hokouensis here. The conservation status of Alseodaphnopsishokouensis is also re-evaluated according to the IUCN Red List Categories and Criteria in this study.

4.
BMC Microbiol ; 24(1): 206, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38858614

RESUMO

OBJECTIVE: This study aims to examine the impact of PE/PPE gene mutations on the transmission of Mycobacterium tuberculosis (M. tuberculosis) in China. METHODS: We collected the whole genome sequencing (WGS) data of 3202 M. tuberculosis isolates in China from 2007 to 2018 and investigated the clustering of strains from different lineages. To evaluate the potential role of PE/PPE gene mutations in the dissemination of the pathogen, we employed homoplastic analysis to detect homoplastic single nucleotide polymorphisms (SNPs) within these gene regions. Subsequently, logistic regression analysis was conducted to analyze the statistical association. RESULTS: Based on nationwide M. tuberculosis WGS data, it has been observed that the majority of the M. tuberculosis burden in China is caused by lineage 2 strains, followed by lineage 4. Lineage 2 exhibited a higher number of transmission clusters, totaling 446 clusters, of which 77 were cross-regional clusters. Conversely, there were only 52 transmission clusters in lineage 4, of which 9 were cross-regional clusters. In the analysis of lineage 2 isolates, regression results showed that 4 specific gene mutations, PE4 (position 190,394; c.46G > A), PE_PGRS10 (839,194; c.744 A > G), PE16 (1,607,005; c.620T > G) and PE_PGRS44 (2,921,883; c.333 C > A), were significantly associated with the transmission of M. tuberculosis. Mutations of PE_PGRS10 (839,334; c.884 A > G), PE_PGRS11 (847,613; c.1455G > C), PE_PGRS47 (3,054,724; c.811 A > G) and PPE66 (4,189,930; c.303G > C) exhibited significant associations with the cross-regional clusters. A total of 13 mutation positions showed a positive correlation with clustering size, indicating a positive association. For lineage 4 strains, no mutations were found to enhance transmission, but 2 mutation sites were identified as risk factors for cross-regional clusters. These included PE_PGRS4 (338,100; c.974 A > G) and PPE13 (976,897; c.1307 A > C). CONCLUSION: Our results indicate that some PE/PPE gene mutations can increase the risk of M. tuberculosis transmission, which might provide a basis for controlling the spread of tuberculosis.


Assuntos
Mutação , Mycobacterium tuberculosis , Polimorfismo de Nucleotídeo Único , Tuberculose , Sequenciamento Completo do Genoma , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/classificação , Mycobacterium tuberculosis/isolamento & purificação , China/epidemiologia , Humanos , Tuberculose/transmissão , Tuberculose/microbiologia , Tuberculose/epidemiologia , Genoma Bacteriano , Feminino , Masculino , Proteínas de Bactérias/genética , Adulto
5.
ACS Nano ; 18(20): 12945-12956, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38717846

RESUMO

P3-layered transition oxide cathodes have garnered considerable attention owing to their high initial capacity, rapid Na+ kinetics, and less energy consumption during the synthesis process. Despite these merits, their practical application is hindered by the substantial capacity degradation resulting from unfavorable structural transformations, Mn dissolution and migration. In this study, we systematically investigated the failure mechanisms of P3 cathodes, encompassing Mn dissolution, migration, and the irreversible P3-O3' phase transition, culminating in severe structural collapse. To address these challenges, we proposed an interfacial spinel local interlocking strategy utilizing P3/spinel intergrowth oxide as a proof-of-concept material. As a result, P3/spinel intergrowth oxide cathodes demonstrated enhanced cycling performance. The effectiveness of suppressing Mn migration and maintaining local structure of interfacial spinel local interlocking strategy was validated through depth-etching X-ray photoelectron spectroscopy, X-ray absorption spectroscopy, and in situ synchrotron-based X-ray diffraction. This interfacial spinel local interlocking engineering strategy presents a promising avenue for the development of advanced cathode materials for sodium-ion batteries.

6.
Mil Med Res ; 11(1): 29, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38741175

RESUMO

Peri-implantitis is a bacterial infection that causes soft tissue inflammatory lesions and alveolar bone resorption, ultimately resulting in implant failure. Dental implants for clinical use barely have antibacterial properties, and bacterial colonization and biofilm formation on the dental implants are major causes of peri-implantitis. Treatment strategies such as mechanical debridement and antibiotic therapy have been used to remove dental plaque. However, it is particularly important to prevent the occurrence of peri-implantitis rather than treatment. Therefore, the current research spot has focused on improving the antibacterial properties of dental implants, such as the construction of specific micro-nano surface texture, the introduction of diverse functional coatings, or the application of materials with intrinsic antibacterial properties. The aforementioned antibacterial surfaces can be incorporated with bioactive molecules, metallic nanoparticles, or other functional components to further enhance the osteogenic properties and accelerate the healing process. In this review, we summarize the recent developments in biomaterial science and the modification strategies applied to dental implants to inhibit biofilm formation and facilitate bone-implant integration. Furthermore, we summarized the obstacles existing in the process of laboratory research to reach the clinic products, and propose corresponding directions for future developments and research perspectives, so that to provide insights into the rational design and construction of dental implants with the aim to balance antibacterial efficacy, biological safety, and osteogenic property.


Assuntos
Materiais Biocompatíveis , Implantes Dentários , Peri-Implantite , Peri-Implantite/terapia , Peri-Implantite/prevenção & controle , Peri-Implantite/tratamento farmacológico , Humanos , Implantes Dentários/normas , Materiais Biocompatíveis/uso terapêutico , Materiais Biocompatíveis/farmacologia , Biofilmes/efeitos dos fármacos , Propriedades de Superfície , Antibacterianos/uso terapêutico , Antibacterianos/farmacologia
7.
Nat Prod Res ; : 1-5, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38813681

RESUMO

The phenomena of intramolecular self-assembly of bidesmosidic kalopanaxsaponins was identified for the first time in this paper. NMR (1H-NMR, NOESY), transmission electron microscopy (TEM), and molecular dynamics (MD) simulation techniques were used to compare the spatial structures of bidesmosidic kalopanaxsaponins and monodesmosidic kalopanaxsaponins. The results showed that the bidesmosidic kalopanaxsaponins formed a clustered and twisted structure in space, whereas the monodesmosidic kalopanaxsaponins were in an extended state. This discovery confirmed the presence of intramolecular self-assembly in bidesmosidic kalopanaxsaponins.

8.
Talanta ; 275: 126173, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38692051

RESUMO

The endoplasmic reticulum (ER) acts as the major storage site for calcium ions, which are messenger ions for intracellular signaling. Disruption of calcium ion homeostasis can significantly affect the viscosity, polarity and pH of the ER. However, it is still unclear the relationship between the viscosity changes in ER and the imbalance of calcium ion homeostasis. Herein, we developed a novel fluorescent probe, named TPA, for monitoring viscosity changes that specifically targets the endoplasmic reticulum rather than mitochondria or lysosomes. TPA probe displayed good stability, as well as high responsiveness and selectivity to viscosity. The fluorescence intensity of TPA was significantly enhanced with the increased concentration or incubation time of the stimulating agents(i.e., tunicamycin), showing high responsiveness to the viscosity changes in ER. Furthermore, the TPA probe successfully demonstrated that an increase in intracellular calcium ion concentration leads to an increase in ER viscosity, whereas a decrease in calcium ion concentration leads to a decrease viscosity in ER. Both in vitro and in vivo experiments demonstrated that TPA probe successfully detected the viscosity changes in ER, especially the effects of calcium ion homeostasis disruption on ER. Overall, the TPA probe represents an efficient method for studying the relationship between calcium ion homeostasis and ER viscosity.


Assuntos
Cálcio , Retículo Endoplasmático , Corantes Fluorescentes , Homeostase , Corantes Fluorescentes/química , Retículo Endoplasmático/metabolismo , Cálcio/metabolismo , Cálcio/análise , Viscosidade , Animais , Humanos , Camundongos , Células HeLa , Fatores de Tempo , Imagem Óptica
9.
Chemosphere ; 356: 141911, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38583539

RESUMO

Oxygen vacancies (OVs) have garnered significant interest for their role as active sites, enhancing the catalytic efficiency of various catalysts. Despite their widespread application in environmental purification processes, the generation of OVs conventionally depends on high-temperature conditions and strong reducing agents for the extraction of surface partial oxygen atoms from catalysts. In this work, bismuth oxybromide (BiOBr) nanosheets with varying levels of OVs were synthesized via a simple and effective solvothermal method. This novel method affords precise control over the conduction band (CB) and valence band (VB) positions of BiOBr. The presence of different OVs exhibited varying photocatalytic efficiencies in the degradation of bisphenol A (BPA) under visible light irradiation, with higher levels of OVs resulting in superior photocatalytic performance. Furthermore, radical scavenger experiments demonstrated that superoxide oxides (O2•-) and holes (h+) were the primary reactive oxygen species for BPA degradation. Additionally, BiOBr-OVs exhibited excellent anti-interference and stability in water matrices containing diverse inorganic anions and organic compounds. This work provides a simple and effective approach for the fine-regulating of catalysts through interfacial defect engineering, paving the way for their practical application in environmental decontamination.


Assuntos
Compostos Benzidrílicos , Bismuto , Oxigênio , Fenóis , Compostos Benzidrílicos/química , Bismuto/química , Fenóis/química , Catálise , Oxigênio/química , Poluentes Químicos da Água/química , Luz , Fotólise
10.
Emotion ; 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38512195

RESUMO

Previous research has shown mixed results regarding the relationship between social class and children's prosocial behavior. The current study aims to further our understanding of these findings by exploring the relationship between social class and children's prosocial behavior in a moral context. Study 1 (N = 833) found that when a target child pursued a morally negative goal and subsequently experienced misfortune, children from higher social class, compared to those from lower social class, experienced greater schadenfreude and exhibited less prosocial behavior. The relation between social class and prosocial behavior was mediated by schadenfreude. Study 2 (N = 389) investigated whether the greater schadenfreude experienced by children from higher social class was due to a weaker empathic response to misfortune or a stronger sense of deservingness. The results revealed a sequential mediation effect of social class on prosocial behavior through deservingness and schadenfreude. These findings provide insight into the impact of social class on the development of children's moral judgment, emotions, and behavior. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

11.
Int J Infect Dis ; 140: 124-131, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37863309

RESUMO

OBJECTIVES: This study aimed to describe the lineage-specific transmissibility and epidemiological migration of Mycobacterium tuberculosis in China. METHODS: We curated a large set of whole-genome sequences from 3204 M. tuberculosis isolates, including thousands of newly sequenced genomes, and applied a series of metrics to compare the transmissibility of M. tuberculosis strains between lineages and sublineages. The countrywide transmission patterns of major lineages were explored. RESULTS: We found that lineage 2 (L2) was the most prevalent lineage in China (85.7%), with the major sublineage 2.2.1 (80.9%), followed by lineage 4 (L4) (13.8%), which comprises major sublineages 4.2 (1.5%), 4.4 (6.2%) and 4.5 (5.8%). We showed evidence for frequent cross-regional spread and large cluster formation of L2.2.1 strains, whereas L4 strains were relatively geographically restricted in China. Next, we applied a series of genomic indices to evaluate M. tuberculosis strain transmissibility and uncovered higher transmissibility of L2.2.1 compared with the L2.2.2 and L4 sublineages. Phylogeographic analysis showed that southern, eastern, and northern China were highly connected regions for countrywide L2.2.1 strain spread. CONCLUSIONS: The present study provides insights into the different transmission and migration patterns of the major M. tuberculosis lineages in China and highlights that transmissible L2.2.1 is a threat to tuberculosis control.


Assuntos
Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Tuberculose , Humanos , Filogenia , Filogeografia , Genótipo , Tuberculose/epidemiologia , Tuberculose/microbiologia , China/epidemiologia , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia
12.
Emerg Microbes Infect ; 13(1): 2294858, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38126135

RESUMO

OBJECTIVES: We investigated the genetic diversities and lineage-specific transmission dynamics of multidrug-resistant tuberculosis (MDR-TB), with the goal of determining the potential factors driving the MDR epidemics in China. METHODS: We curated a large nationwide Mycobacterium tuberculosis (M. tuberculosis) whole genome sequence data set, including 1313 MDR strains. We reconstructed the phylogeny and mapped the transmission networks of MDR-TB across China using Bayesian inference. To identify drug-resistance variants linked to enhanced transmissibility, we employed ordinary least-squares (OLS) regression analysis. RESULT: The majority of MDR-TB strains in China belong to lineage 2.2.1. Transmission chain analysis has indicated that the repeated and frequent transmission of L2.2.1 plays a central role in the establishment of MDR epidemic in China, but no occurrence of a large predominant MDR outbreak was detected. Using OLS regression, the most common single nucleotide polymorphisms (SNPs) associated with resistance to isoniazid (katG_p.Ser315Thr and katG_p.Ser315Asn) and rifampicin (rpoB_p.Ser450Leu, rpoB_p.His445Tyr, rpoB_p.His445Arg, rpoB_p.His445Asp, and rpoB_p.His445Asn) were more likely to be found in L2 clustered strains. Several putative compensatory mutations in rpoA, rpoC, and katG were significantly associated with clustering. The eastern, central, and southern regions of China had a high level of connectivity for the migration of L2 MDR strains throughout the country. The skyline plot showed distinct population size expansion dynamics for MDR-TB lineages in China. CONCLUSION: MDR-TB epidemic in China is predominantly driven by the spread of highly transmissible Beijing strains. A range of drug-resistance mutations of L2 MDR-TB strains displayed minimal fitness costs and may facilitate their transmission.


Assuntos
Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Humanos , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Teorema de Bayes , Genótipo , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Mycobacterium tuberculosis/genética , Mutação , China/epidemiologia , Genômica , Resistência a Múltiplos Medicamentos , Farmacorresistência Bacteriana Múltipla/genética , Testes de Sensibilidade Microbiana
13.
Nat Metab ; 5(10): 1726-1746, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37770763

RESUMO

Chronic inflammation due to islet-residing macrophages plays key roles in the development of type 2 diabetes mellitus. By systematically profiling intra-islet lipid-transmembrane receptor signalling in islet-resident macrophages, we identified endogenous 9(S)-hydroxy-10,12-octadecadienoic acid-G-protein-coupled receptor 132 (GPR132)-Gi signalling as a significant contributor to islet macrophage reprogramming and found that GPR132 deficiency in macrophages reversed metabolic disorders in mice fed a high-fat diet. The cryo-electron microscopy structures of GPR132 bound with two endogenous agonists, N-palmitoylglycine and 9(S)-hydroxy-10,12-octadecadienoic acid, enabled us to rationally design both GPR132 agonists and antagonists with high potency and selectivity through stepwise translational approaches. We ultimately identified a selective GPR132 antagonist, NOX-6-18, that modulates macrophage reprogramming within pancreatic islets, decreases weight gain and enhances glucose metabolism in mice fed a high-fat diet. Our study not only illustrates that intra-islet lipid signalling contributes to islet macrophage reprogramming but also provides a broadly applicable strategy for the identification of important G-protein-coupled receptor targets in pathophysiological processes, followed by the rational design of therapeutic leads for refractory diseases such as diabetes.


Assuntos
Diabetes Mellitus Tipo 2 , Ilhotas Pancreáticas , Camundongos , Animais , Diabetes Mellitus Tipo 2/metabolismo , Microscopia Crioeletrônica , Ilhotas Pancreáticas/metabolismo , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais
14.
Chem Commun (Camb) ; 59(71): 10672-10675, 2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37581899

RESUMO

A series of seaweed-like heterogeneous Co3(PO4)2/Ni3(PO4)2/MOF-74-x electrocatalysts were synthesized via a hydrothermal method. The optimal composite exhibits excellent catalytic performance toward methanol/ethanol oxidation reactions (MOR/EOR) with peak current densities reaching 27.5 and 32.6 mA cm-2, respectively. This work heralds the advent of more efficient heterogeneous electrocatalysts for DAFCs and other energy conversion systems.

15.
Front Psychol ; 14: 1171939, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37484105

RESUMO

To verify the effect of sleep ambient music intervention (SAMI) on sleep quality and mental status of college students, and to further explore the minimum effective duration of SAMI, this study was designed as a pre-and post-intervention self-controlled exploratory study. Participants were subjected to a one-week no-intervention test, then 4 weeks of music intervention followed. Subjective sleep quality data were collected using the Pittsburgh Sleep Quality Index (PSQI); objective sleep quality data were collected with Actigraphy; and mental status data were collected using the State-Trait Anxiety Inventory (STAI) and the Beck Depression Inventory-II (BDI-II). Data were analyzed and processed using mixed-effects models and repeated measures. The results showed that compared with the no-intervention week, college students' subjective sleep quality, objective sleep onset latency (SOL), trait anxiety, and depression symptom were reduced at week 1; week 2; week 3; week 4 under SAMI; state anxiety of college students at week 3 and week 4 under SAMI were also reduced. And there were differences in sleep quality among college students of different genders too. Compared with females, males had worse sleep efficiency (SE), shorter total sleep time (TST), and more awaking times (AT). In addition, 3 days was the minimum effective length for SAMI to shorten objective SOL, and 2 days was the minimum effective length to shorten the subjective SOL of college students. The findings of this study suggest that SAMI can improve subjective sleep quality, shorten objective SOL, and reduce anxiety and depression in college students. Interventions for more than 3 days had a significant effect on shortening SOL and long-term effects seemed to emerge after 3 weeks.

16.
Small ; 19(44): e2303666, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37407518

RESUMO

Na3 (VO)2 (PO4 )2 F (NVOPF) has emerged as one of the most promising cathode materials for sodium-ion batteries (SIBs) attributed to its high specific capacity (130 mAh g-1 ), high operation voltage (>3.9 V vs Na+ /Na), and excellent structural stability (<2% volume change). However, the comparatively low intrinsic electronic conductivity (≈10-7 S cm-1 ) of NVOPF leads to unsatisfactory electrochemical performance, especially at high rates, limiting its practical applications. To improve the conductivity and enhance Na storage performance, many efforts have been devoted to designing NVOPF, including morphology optimization, hybridization with conductive materials, metal-ion doping, Na-site regulation, and F/O ratio adjustment. These attempts have shown some encouraging achievements and shed light on the practical application of NVOPF cathodes. This work aims to provide a general introduction, synthetic methods, and rational design of NVOPF to give a deeper understanding of the recent progress. Additionally, the unique microstructure of NVOPF and its relationship with Na storage properties are also described in detail. The current status, as well as the advances and limitations of such SIB cathode material, are reported. Finally, future perspectives and guidance for advancing high-performance NVOPF cathodes toward practical applications are presented.

17.
Heliyon ; 9(8): e18545, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37520985

RESUMO

Hydrocolloids as Additives have been used for improving the quality of frozen dough for a long time. In this work, the effects of sodium carboxymethyl cellulose (CMC) on quality changes of frozen dough in storage were studied. The water loss rate of the dough and water holding capacity were measured. Rheological and texture properties of the frozen dough were measured by a rheometer and a texture analyzer, respectively. Scanning electron microscopy (SEM) was used to characterize surface network structure and protein structure changes of the frozen dough. Our results reveal that the addition of CMC can inhibit the formation of ice crystals and recrystallization, thus effectively stabilizing the molecular structure of starch, and resulting in more uniform moisture distribution in the frozen dough. When 3% addition of CMC, the water holding capacity of the two kinds of dough reached the best, and the water loss rate of corn dough reached the lowest. The cohesion of the two kinds of dough reaches the maximum with 3 wt% addition of CMC, while the hardness and chewiness of wheat and corn multigrain dough reaches the maximum with 3 wt% and 4 wt% addition of CMC, respectively. The results show proper CMC addition (3 wt% and 4 wt%) finally improves the stability and qualities of the frozen dough. The research concerning the effects of CMC on quality of frozen dough provides better understanding for the frozen food industry.

18.
Inorg Chem ; 62(26): 10256-10262, 2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37344358

RESUMO

Two-dimensional metal-organic framework (MOF) crystalline materials possess promising potential in the electrochemical sensing process owing to their tunable structures, high specific surface area, and abundant metal active sites; however, developing MOF-based nonenzymatic glucose (Glu) sensors which combine electrochemical activity and environmental stability remains a challenge. Herein, utilizing the tripodic nitrogen-bridged 1,3,5-tris(1-imidazolyl) benzene (TIB) linker, Co2+ and Ni2+, two 2D isomorphic crystalline materials, including Co/Ni-MOF {[Co (TIB)]·2BF4} (CTGU-31) and {[Ni(TIB)]·2NO3} (CTGU-32), with a binodal (3, 6)-connected kgd topological net were firstly synthesized and fabricated with conducting acetylene black (AB). When modified on a glassy carbon electrode, the optimized AB/CTGU-32 (1:1) electrocatalyst demonstrated a higher sensitivity of 2.198 µA µM-1 cm-2, a wider linear range from 10 to 4000 µM, and a lower detection limit (LOD) value (0.09 µM, S/N = 3) compared to previously MOF-based Glu sensors. Moreover, AB/CTGU-32 (1:1) exhibited desirable stability for at least 2000 s during the electrochemical process. The work indicates that MOF-based electrocatalysts are a promising candidate for monitoring Glu and demonstrate their potential for preliminary screening for diabetes.


Assuntos
Estruturas Metalorgânicas , Estruturas Metalorgânicas/química , Carbono/química , Níquel/química , Eletrodos , Acetileno , Glucose/química
19.
Chem Commun (Camb) ; 59(43): 6533-6535, 2023 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-37159050

RESUMO

A zinc-infiltration process was adopted to prepare silver-doped copper nanosheet arrays. The larger atomic radius of Ag introduces tensile stress, which lowers the electron density at the s-orbitals of Cu atoms and improves the adsorption capability for hydrogen atoms. As a catalyst for hydrogen evolution, these silver doped copper nanosheet arrays achieved a low overpotential of 103 mV at 10 mA cm-2 in 1 M KOH, which is 604 mV lower than that of pure copper foil.

20.
Dalton Trans ; 52(23): 7819-7827, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37212634

RESUMO

Transition metal sulfides are low-cost oxygen evolution reaction (OER) electrocatalysts that can potentially substitute noble metal catalysts. However, the adsorption process of their OER is impeded by their intrinsic poor catalytic activity. Constructing heterojunction and vacancy defects in transition metal sulfides is an efficient method to promote the process of oxygen evolution. Herein, a facile approach based on in situ sulfurization of metal-organic gels (MOGs) and a short-time plasma treatment was developed to fabricate vacancy-modified polymetallic sulfides heterojunction. The synergistic effect of the multi-component heterojunction and sulfur vacancy contributed greatly to improving the electron migration efficiency and OER ability of the electrocatalyst. As a result, the optimum oxygen evolution activity was achieved with appropriate surface vacancy concentrations by regulating the plasma radio frequency powers. The plasma-treated catalyst under 400 W showed the best OER performance (lower overpotential of 235 mV in 1 M KOH solution with the Tafel slope of 31 mV dec-1) and good durability over 11 h of chronopotentiometry testing. This work sheds new light on constructing multimetal-based heterojunction electrocatalysts with rich vacancy defects for oxygen evolution reactions.

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