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1.
Mol Cell Biochem ; 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39138750

RESUMO

Postoperative cognitive dysfunction (POCD) impacts a significant number of patients annually, frequently impairing their cognitive abilities and resulting in unfavorable clinical outcomes. Aimed at addressing cognitive impairment, vagus nerve stimulation (VNS) is a therapeutic approach, which was used in many mental disordered diseases, through the modulation of vagus nerve activity. In POCD model, the enhancement of cognition function provided by VNS was shown, demonstrating VNS effect on cognition in POCD. In the present study, we primarily concentrates on elucidating the role of the VNS improving the cognitive function in POCD, via two potential mechanisms: the inflammatory microenvironment and epigenetics. This study provided a theoretical support for the feasibility that VNS can be a potential method to enhance cognition function in POCD.

2.
Front Neurosci ; 18: 1415576, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39145297

RESUMO

Introduction: We previously reported that ATP1A3 c.823G>C (p.Ala275Pro) mutant causes varying phenotypes of alternative hemiplegia of childhood and rapid-onset dystonia-parkinsonism in the same family. This study aims to investigate the function of ATP1A3 c.823G>C (p.Ala275Pro) mutant at the cellular and zebrafish models. Methods: ATP1A3 wild-type and mutant Hela cell lines were constructed, and ATP1A3 mRNA expression, ATP1A3 protein expression and localization, and Na+-K+-ATPase activity in each group of cells were detected. Additionally, we also constructed zebrafish models with ATP1A3 wild-type overexpression (WT) and p.Ala275Pro mutant overexpression (MUT). Subsequently, we detected the mRNA expression of dopamine signaling pathway-associated genes, Parkinson's disease-associated genes, and apoptosisassociated genes in each group of zebrafish, and observed the growth, development, and movement behavior of zebrafish. Results: Cells carrying the p.Ala275Pro mutation exhibited lower levels of ATP1A3 mRNA, reduced ATP1A3 protein expression, and decreased Na+-K+-ATPase activity compared to wild-type cells. Immunofluorescence analysis revealed that ATP1A3 was primarily localized in the cytoplasm, but there was no significant difference in ATP1A3 protein localization before and after the mutation. In the zebrafish model, both WT and MUT groups showed lower brain and body length, dopamine neuron fluorescence intensity, escape ability, swimming distance, and average swimming speed compared to the control group. Moreover, overexpression of both wild-type and mutant ATP1A3 led to abnormal mRNA expression of genes associated with the dopamine signaling pathway and Parkinson's disease in zebrafish, and significantly upregulated transcription levels of bad and caspase-3 in the apoptosis signaling pathway, while reducing the transcriptional level of bcl-2 and the bcl-2/bax ratio. Conclusion: This study reveals that the p.Ala275Pro mutant decreases ATP1A3 protein expression and Na+/K+-ATPase activity. Abnormal expression of either wild-type or mutant ATP1A3 genes impairs growth, development, and movement behavior in zebrafish.

3.
Heliyon ; 10(11): e32377, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38947486

RESUMO

Acute kidney injury (AKI) frequently emerges as a consequential non-neurological sequel to traumatic brain injury (TBI), significantly contributing to heightened mortality risks. The intricate interplay of oxidative stress in the pathophysiology of TBI underscores the centrality of the Keap1-Nrf2/HO-1 signaling pathway as a pivotal regulator in this context. This study endeavors to elucidate the involvement of the Keap1-Nrf2/HO-1 pathway in modulating oxidative stress in AKI subsequent to TBI and concurrently explore the therapeutic efficacy of dimethyl fumarate (DMF). A rat model of TBI was established via the Feeney free-fall method, incorporating interventions with varying concentrations of DMF. Assessment of renal function ensued through measurements of serum creatinine and neutrophil gelatinase-associated lipocalin. Morphological evaluation of renal pathology was conducted employing quantitative hematoxylin and eosin staining. The inflammatory response was scrutinized by quantifying interleukin (IL)-6, IL-1ß, and tumor necrosis factor-α levels. Oxidative stress levels were discerned through quantification of malondialdehyde and superoxide dismutase. The apoptotic cascade was examined via the terminal deoxynucleotidyl transferase dUTP deletion labeling assay. Western blotting provided insights into the expression dynamics of proteins affiliated with the Keap1-Nrf2/HO-1 pathway and apoptosis. The findings revealed severe kidney injury, heightened oxidative stress, inflammation, and apoptosis in the traumatic brain injury model. Treatment with DMF effectively reversed these changes, alleviating oxidative stress by activating the Keap1-Nrf2/HO-1 signaling pathway, ultimately conferring protection against AKI. Activating Keap1-Nrf2/HO-1 signaling pathway may be a potential therapeutic strategy for attenuating oxidative stress-induced AKI after TBI.

4.
Int J Cardiol ; 412: 132338, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38964551

RESUMO

BACKGROUND: Surprisingly, despite the high prevalence of metformin use in type 2 diabetes (T2D) patients with heart disease, limited safety data is available regarding metformin use in patients with acute and critical heart disease. METHODS: In this single-center retrospective study, patients admitted to the cardiology department for heart failure (HF) or acute coronary syndrome (ACS) between December 2013 and December 2021 and who underwent arterial blood gas analysis at admission with an estimated glomerular clearance rate of ≥45 ml/min/1.73 m2 were identified. The incidences of hyperlactatemia, acidosis, and 30-day in-hospital mortality were compared between preadmission metformin users and nonusers. RESULTS: Of 526 admissions, 193/193 metformin users/nonusers were selected in a propensity score-matched model. Metformin users had greater lactate levels (2.55 ± 2.07 mmol/l vs. 2.00 ± 1.80 mmol/l P < 0.01), a greater incidence of hyperlactatemia [odds ratio (OR) = 2.55; 95% confidence interval (CI), 1.63-3.98; P < 0.01] and acidosis (OR = 1.78; 95% CI, 1.00-3.16; P < 0.05) at admission and a greater incidence of in-hospital mortality (OR = 3.83; 95% CI, 1.05-13.94; P < 0.05), especially those with HF/acute myocardial infarction, elderly age, or without preadmission insulin use. CONCLUSIONS: Our results suggest that, compared to metformin nonusers, preadmission use of metformin may be associated with a greater incidence of hyperlactatemia and acidosis at admission and greater 30-day in-hospital mortality among T2D patients with HF or ACS at high risk of hypoxia, particularly those without preadmission insulin use. The safety of metformin in this population needs to be confirmed in prospective controlled trials.


Assuntos
Diabetes Mellitus Tipo 2 , Mortalidade Hospitalar , Hiperlactatemia , Hipoglicemiantes , Metformina , Humanos , Metformina/uso terapêutico , Metformina/efeitos adversos , Masculino , Feminino , Mortalidade Hospitalar/tendências , Estudos Retrospectivos , Idoso , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/mortalidade , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/epidemiologia , Hiperlactatemia/epidemiologia , Hiperlactatemia/sangue , Hiperlactatemia/induzido quimicamente , Incidência , Hipoglicemiantes/uso terapêutico , Hipoglicemiantes/efeitos adversos , Pessoa de Meia-Idade , Hipóxia/epidemiologia , Hipóxia/mortalidade , Hipóxia/sangue , Admissão do Paciente/tendências , Cardiopatias/epidemiologia , Cardiopatias/mortalidade , Cardiopatias/sangue , Idoso de 80 Anos ou mais , Fatores de Risco
5.
ChemMedChem ; : e202400302, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38946213

RESUMO

Antibiotics, particularly the ß-lactams, are a cornerstone of modern medicine. However, the rise of bacterial resistance to these agents, particularly through the actions of ß-lactamases, poses a significant threat to our continued ability to effectively treat infections. Metallo-ß-lactamases (MBLs) are of particular concern due to their ability to hydrolyze a wide range of ß-lactam antibiotics including carbapenems. For this reason there is growing interest in the development of MBL inhibitors as well as novel antibiotics that can overcome MBL-mediated resistance. Here, we report the synthesis and evaluation of novel conjugates that combine a carbapenem (meropenem or ertapenem) with a recently reported MBL inhibiting indole carboxylate scaffold. These hybrids were found to display potent inhibition against MBLs including NDM-1 and IMP-1, with IC50 values in the low nanomolar range. However, their antibacterial potency was limited. Mechanistic studies suggest that despite maintaining effective MBL inhibiting activity in live bacteria, the new carbapenem/MBL inhibitor conjugates have a reduced ability to engage with the bacterial target of the ß-lactams.

6.
Ying Yong Sheng Tai Xue Bao ; 35(4): 1150-1158, 2024 Apr 18.
Artigo em Chinês | MEDLINE | ID: mdl-38884250

RESUMO

Functional traits are indicators of the responses and adaptation of organisms to environmental changes and cascade to a series of ecosystem functions. The functional traits of soil animals are sensitive to environmental factors and may characterize and predict the changes of ecosystem functions. Multiple dimensions of biodiversity that combing species, phylogenetic, and functional diversity improves the understanding of distribution patterns, community assembly mechanisms and ecosystem functions of soil animals. In this review, we listed the categories of soil animal functional traits and their ecological significance, and summarized current researches on the responses of soil animal communities to environmental changes and the community assembly processes based on trait-based approaches. We proposed to strengthen the study on the impacts of eco-evolution processes of biotic interactions to soil animal functional traits, establish the database of soil animal functional traits, and apply trait-based approaches in the ecological restoration in the future, which would benefit soil biodiversity conservation and sustainability of soil ecosystems.


Assuntos
Biodiversidade , Ecossistema , Solo , Animais , Conservação dos Recursos Naturais , Ecologia , Distribuição Animal
7.
Angew Chem Int Ed Engl ; 63(34): e202404084, 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-38863431

RESUMO

Stimuli-responsive physisorbents that undergo reversible structural transformations induced by external stimuli (e.g. light, guests, or heat) offer the promise of utility in gas storage and separation. Whereas reports on guest or light-responsive sorbents have increased in recent years, we are unaware of reports on sorbents that exhibit both light and guest-induced structural transformations. Herein, we report that the square lattice, sql, topology coordination network Zn(fba)(bis) ⋅ 2DMF (sql-5,6-Zn-α, 5=trans-4,4'-bis(1-imidazolyl)stilbene=bis, 6=2,2-bis(4-carboxyphenyl)hexafluoropropane=H2fba) underwent single-crystal-to-single-crystal transformation (SCSC) upon activation, affording nonporous sql-5,6-Zn-ß. Parallel alignment at 3.23 Šof olefinic moieties on adjacent bis ligands in sql-5,6-Zn-α enabled SCSC [2+2] photocycloaddition upon exposure to UV light (365 nm) or sunlight. sql-5,6-Zn-α thereby transformed to mot-5,6-Zn-α, which was subsequently activated to the narrow pore phase mot-5,6-Zn-ß. sql-5,6-Zn-ß and mot-5,6-Zn-ß both exhibited S-shaped adsorption isotherms characteristic of guest-induced structural changes when exposed to CO2 at 195 K (type-F-IV and type F-I, respectively). Cycling experiments conducted upon sql-5,6-Zn-ß reduced particle size after cycle 1 and induced transformation into a rare example of a shape memory coordination network, sql-5,6-Zn-γ. Insight into this smorgasbord of SCSC phase changes was gained from in situ PXRD, single crystal XRD and 1H NMR spectroscopy experiments.

8.
Small ; : e2402523, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38747010

RESUMO

A 44.610.8 topology hybrid ultramicroporous material (HUM), {[Cu1.5F(SiF6)(L)2.5]·G}n, (L = 4,4'-bisimidazolylbiphenyl, G = guest molecules), 1, formed by cross-linking interpenetrated 3D four-connected CdSO4-type nets with hexafluorosilicate anions is synthesized and evaluated in the context of gas sorption and separation herein. 1 is the first HUM functionalized with two different types of fluorinated sites (SiF6 2- and F- anions) lining along the pore surface. The optimal pore size (≈5 Å) combining mixed and high-density electronegative fluorinated sites enable 1 to preferentially adsorb C2H2 over CO2 and C2H4 by hydrogen bonding interactions with a high C2H2 isosteric heat of adsorption (Qst) of ≈42.3 kJ mol-1 at zero loading. The pronounced discriminatory sorption behaviors lead to excellent separation performance for C2H2/CO2 and C2H2/C2H4 that surpasses many well-known sorbents. Dynamic breakthrough experiments are conducted to confirm the practical separation capability of 1, which reveal an impressive separation factor of 6.1 for equimolar C2H2/CO2 mixture. Furthermore, molecular simulation and density functional theory (DFT) calculations validate the strong binding of C2H2 stems from the chelating fix of C2H2 between SiF6 2- anion and coordinated F- anion.

9.
Kidney Int Rep ; 9(4): 1057-1066, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38765575

RESUMO

Introduction: Immunoglobulin A nephropathy (IgAN) has been reported to coexist with hepatitis B virus (HBV) infection. Despite the clinical significance of this association, there is a lack of comprehensive research investigating the impact of various common conditions following HBV infection and the potential influence of anti-HBV therapy on the progression of IgAN. Methods: We investigated 3 distinct states of HBV infection, including chronic HBV infection, resolved HBV infection, and the deposition of hepatitis B antigens in renal tissue, in a follow-up database of 1961 patients with IgAN. IgAN progression was defined as a loss of estimated glomerular filtration rate (eGFR) >40%. Multivariable cause-specific hazards models to analyze the relationship between HBV states and IgAN progression. Results: Chronic HBV infection was identified as an independent risk factor for IgAN progression, supported by both prematching analysis (hazard ratio [HR], 1.61; 95% confidence interval [CI], 1.06-2.44; P = 0.024) and propensity-score matching analysis (HR, 1.74; 95% CI 1.28-2.37; P < 0.001). Conversely, resolved HBV infection showed no significant association with IgAN progression (HR, 1.01; 95% CI 0.67-1.52; P = 0.969). Moreover, the presence of HBV deposition in the kidneys and the utilization of anti-HBV therapy did not appear to be significant risk factors for renal outcomes (P > 0.05). Conclusion: Chronic HBV infection is an independent risk factor for IgAN progression, whereas resolved HBV infection is not. In patients with IgAN, management of concurrent chronic HBV infection should be enhanced. The presence of HBV deposition in the kidneys and the use of anti-HBV medications do not impact the kidney disease progression in patients with IgAN with concurrent HBV infection.

10.
Dig Dis Sci ; 69(6): 2109-2122, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38564148

RESUMO

BACKGROUND: Cholesterol ester storage disorder (CESD; OMIM: 278,000) was formerly assumed to be an autosomal recessive allelic genetic condition connected to diminished lysosomal acid lipase (LAL) activity due to LIPA gene abnormalities. CESD is characterized by abnormal liver function and lipid metabolism, and in severe cases, liver failure can occur leading to death. In this study, one Chinese nonclassical CESD pedigree with dominant inheritance was phenotyped and analyzed for the corresponding gene alterations. METHODS: Seven males and eight females from nonclassical CESD pedigree were recruited. Clinical features and LAL activities were documented. Whole genome Next-generation sequencing (NGS) was used to screen candidate genes and mutations, Sanger sequencing confirmed predicted mutations, and qPCR detected LIPA mRNA expression. RESULTS: Eight individuals of the pedigree were speculatively thought to have CESD. LAL activity was discovered to be lowered in four living members of the pedigree, but undetectable in the other four deceased members who died of probable hepatic failure. Three of the four living relatives had abnormal lipid metabolism and all four had liver dysfunctions. By liver biopsy, the proband exhibited diffuse vesicular fatty changes in noticeably enlarged hepatocytes and Kupffer cell hyperplasia. Surprisingly, only a newly discovered heterozygous mutation, c.1133T>C (p. Ile378Thr) on LIPA, was found by gene sequencing in the proband. All living family members who carried the p.I378T variant displayed reduced LAL activity. CONCLUSIONS: Phenotypic analyses indicate that this may be an autosomal dominant nonclassical CESD pedigree with a LIPA gene mutation.


Assuntos
Doença do Armazenamento de Colesterol Éster , Heterozigoto , Linhagem , Esterol Esterase , Humanos , Masculino , Feminino , Doença do Armazenamento de Colesterol Éster/genética , Doença do Armazenamento de Colesterol Éster/diagnóstico , Esterol Esterase/genética , Adulto , Mutação , Genes Dominantes , Pessoa de Meia-Idade , Fenótipo , Adolescente , Criança
12.
Int J Surg ; 110(6): 3285-3293, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38498404

RESUMO

PURPOSE: Previous studies have explored the role of immune cells on osteonecrosis. This Mendelian randomization (MR) study further assessed 731 immunocyte phenotypes on osteonecrosis, whether a causal relationship exists, and provides some evidence of causality. METHODS: The 731 immunocyte phenotypes and osteonecrosis data used in this study were obtained from their respective genome-wide association studies (GWAS). The authors used inverse variable weighting (IVW) as the primary analysis method. In addition, the authors simultaneously employed multiple analytical methods, including MR-Egger, weighted mode, simple mode, and weighted median, to strengthen the final results. Finally, sensitivity analyses were conducted to verify the stability and feasibility of the data. RESULTS: The results of the IVW method of MR analysis showed that 8 immunocyte phenotypes were positively associated with osteonecrosis [ P <0.05, odds ratio (OR) > 1]; 18 immunocyte phenotypes were negatively associated with osteonecrosis ( P <0.05, OR<1), none of which were heterogeneous or horizontally pleiotropic ( P > 0.05) or reverse causality. In addition to this, in reverse MR, osteonecrosis was positively associated with 10 additional immunocyte phenotypes ( P <0.05, OR > 1) and negatively associated with 14 immunocyte phenotypes ( P <0.05, OR<1). And none of them had heterogeneity and horizontal pleiotropy ( P > 0.05) or reverse causality. CONCLUSIONS: The authors demonstrated a complex causal relationship between multiple immune phenotypes and osteonecrosis through a comprehensive two-way, two-sample MR analysis, highlighting the complex pattern of interactions between the immune system and osteonecrosis.


Assuntos
Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Osteonecrose , Fenótipo , Humanos , Osteonecrose/genética , Osteonecrose/imunologia , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único
13.
Nat Commun ; 15(1): 1656, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38472219

RESUMO

The rapid development of organic-inorganic hybrid perovskite solar cells has resulted in laboratory-scale devices having power conversion efficiencies that are competitive with commercialised technologies. However, hybrid perovskite solar cells are yet to make an impact beyond the research community, with translation to large-area devices fabricated by industry-relevant manufacturing methods remaining a critical challenge. Here we report the first demonstration of hybrid perovskite solar cell modules, comprising serially-interconnected cells, produced entirely using industrial roll-to-roll printing tools under ambient room conditions. As part of this development, costly vacuum-deposited metal electrodes are replaced with printed carbon electrodes. A high-throughput experiment involving the analysis of batches of 1600 cells produced using 20 parameter combinations enabled rapid optimisation over a large parameter space. The optimised roll-to-roll fabricated hybrid perovskite solar cells show power conversion efficiencies of up to 15.5% for individual small-area cells and 11.0% for serially-interconnected cells in large-area modules. Based on the devices produced in this work, a cost of ~0.7 USD W-1 is predicted for a production rate of 1,000,000 m² per year in Australia, with potential for further significant cost reductions.

14.
Ann Hematol ; 103(5): 1765-1774, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38509388

RESUMO

Gaucher disease (GD) is an autosomal recessive ailment resulting from glucocerebrosidase deficiency caused by a mutation in the GBA1 gene, leading to multi-organ problems in the liver, spleen, and bone marrow. In China, GD is extremely uncommon and has a lower incidence rate than worldwide. In this study, we report the case of an adult male with an enlarged spleen for 13 years who presented with abdominal distension, severe loss of appetite and weight, reduction of the three-line due to hypersplenism, frequent nosebleeds, and bloody stools. Regrettably, the unexpected discovery of splenic pathology suggestive of splenic Gaucher disease was only made after a splenectomy due to a lack of knowledge about rare disorders. Our patient's delayed diagnosis may have been due to the department where he was originally treated, but it highlights the need for multidisciplinary consultation in splenomegaly of unknown etiology. We then investigated the patient's clinical phenotypes and gene mutation features using genetically phenotypical analysis. The analysis of the GBA1 gene sequence indicated that the patient carried a compound heterozygous mutation consisting of two potentially disease-causing mutations: c.907C > A (p. Leu303Ile) and c.1448 T > C (p. Leu483Pro). While previous research has linked the p. Leu483Pro mutation site to neurologic GD phenotypes (GD2 and GD3), the patients in this investigation were identified as having non-neuronopathic GD1. The other mutation, p. Leu303Ile, is a new GD-related mutation not indexed in PubMed that enriches the GBA1 gene mutation spectrum. Biosignature analysis has shown that both mutations alter the protein's three-dimensional structure, which may be a pathogenic mechanism for GD1 in this patient.


Assuntos
Doença de Gaucher , Esplenopatias , Adulto , Humanos , Masculino , Doença de Gaucher/complicações , Doença de Gaucher/genética , Doença de Gaucher/cirurgia , Esplenectomia , Medula Óssea , Fenótipo , Esplenomegalia/genética , Mutação , Glucosilceramidase/genética
15.
ACS Macro Lett ; 13(3): 361-367, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38457308

RESUMO

Bioadhesives have garnered widespread attention in the biomedical field, for wound healing and tissue sealing. However, challenges exist due to the inferior performance of bioadhesives, including weak adhesion, poor biocompatibility, or lack of biodegradability. In this work, we demonstrate the fabrication of hydrogel adhesive based on polypeptides composed of lysine and glutamic acid. The cation-π interaction between the ammonium cations and phenyl groups endows the hydrogel with strong cohesion, and the hydrophobicity of the phenyl group significantly enhances the interaction between polypeptides and the substrate interface, leading to excellent adhesive performance. The equivalent molar ratio of ammonium cations and the phenyl group is beneficial for the enhancement of adhesiveness. Furthermore, we discover that the polypeptides with an α-helix exhibit better adhesiveness than the polypeptides with a ß-sheet because the α-helical structure can increase the exposure of the side group on the polypeptide surface, which further strengthens the interaction between polypeptides and the substrate. Besides, this synthetic polypeptide adhesive can seal the tissue quickly and remain intact in water. This adhesive holds significant promise for application in wound healing and tissue sealing, and this study provides insight into the development of more peptide-based adhesives.


Assuntos
Adesivos , Compostos de Amônio , Adesivos/química , Peptídeos/química , Hidrogéis/química , Cátions
16.
ACS Appl Mater Interfaces ; 16(8): 10459-10467, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38358426

RESUMO

Inverted colloidal-nanocrystal-based LEDs (NC-LEDs) are highly interesting and invaluable for large-scale display technology and flexible electronics. Semiconductor nanorods (NRs), in addition to the tunable wavelengths of the emitted light (achieved, for example, by the variation of the NR diameter or the diameter of core in a core-shell configuration), also exhibit linearly polarized emission, a larger Stokes shift, faster radiative decay, and slower bleaching kinetics than quantum dots (QDs). Despite these advantages, it is difficult to achieve void-free active NR layers using simple spin-coating techniques. Herein, we employ electrophoretic deposition (EPD) to make closely packed, vertically aligned CdSe/CdS core/shell nanorods (NRs) as the emissive layer. Following an inverted architecture, the device fabricated yields an external quantum efficiency (EQE) of 6.3% and a maximum luminance of 4320 cd/m2 at 11 V. This good performance can be attributed to the vertically aligned NR layer, enhancing the charge transport by reducing the resistance of carrier passage, which is supported by our finite element simulations. To the best of our knowledge, this is the first time vertically aligned NR layers made by EPD have been reported for the fabrication of NC-LEDs and the device performance is one of the best for inverted red NR-LEDs. The findings presented in this work bring forth a simple and effective technique for making vertically aligned NRs, and the mechanism behind the NR-LED device with enhanced performance using these NRs is illustrated. This technique may prove useful to the development of a vast class of nanocrystal-based optoelectronics, including solar cells and laser devices.

17.
Biomacromolecules ; 25(3): 1897-1905, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38330502

RESUMO

The low emission efficiency of clusteroluminogens restricts their practical applications in the fields of sensors and biological imaging. In this work, the clusteroluminescence of ordered/disordered polypeptides was observed, and the photoluminescence (PL) intensity of polypeptides can be modulated by the chirality of amino acid residues. Polyglutamates with different chiral compositions were synthesized, and the racemic polypeptides exhibited a significantly higher PL intensity than the enantiopure ones. This emission originates from the n-π* transition between C═O groups of polypeptides and is enhanced by clusterization of polypeptides. CD and Fourier transform infrared spectra demonstrated that the enantiopure and racemic polypeptides form α-helix and random coil structures, respectively. The disordered polypeptides can form more chain entanglements and interchain interactions because of their high flexibility, leading to more clusterizations and stronger PL intensity. The rigidity of ordered helical structures restrains the chain entanglements, and the formation of intrachain hydrogen bonds between amide groups of the backbone impairs the interchain interaction between polypeptides, resulting in lower PL intensity. The PL intensity of the polypeptides can also be manipulated by the addition of urea or trifluoroacetic acid. Our study not only elucidates the chirality/order-based structure-property relationship of clusteroluminescence in peptide-based polymers but also offers implications for the rational design of fluorescent peptides/proteins.


Assuntos
Peptídeos , Proteínas , Estrutura Secundária de Proteína , Peptídeos/química , Aminoácidos
18.
ACS Mater Lett ; 6(1): 56-65, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38178981

RESUMO

Propane (C3H8) is a widely used fuel gas. Metal-organic framework (MOF) physisorbents that are C3H8 selective offer the potential to significantly reduce the energy footprint for capturing C3H8 from natural gas, where C3H8 is typically present as a minor component. Here we report the C3H8 recovery performance of a previously unreported lonsdaleite, lon, topology MOF, a chiral metal-organic material, [Ni(S-IEDC)(bipy)(SCN)]n, CMOM-7. CMOM-7 was prepared from three low-cost precursors: Ni(SCN)2, S-indoline-2-carboxylic acid (S-IDECH), and 4,4'-bipyridine (bipy), and its structure was determined by single crystal X-ray crystallography. Pure gas adsorption isotherms revealed that CMOM-7 exhibited high C3H8 uptake (2.71 mmol g-1) at 0.05 bar, an indication of a higher affinity for C3H8 than both C2H6 and CH4. Dynamic column breakthrough experiments afforded high purity C3H8 capture from a gas mixture comprising C3H8/C2H6/CH4 (v/v/v = 5/10/85). Despite the dilute C3H8 stream, CMOM-7 registered a high dynamic uptake of C3H8 and a breakthrough time difference between C3H8 and C2H6 of 79.5 min g-1, superior to those of previous MOF physisorbents studied under the same flow rate. Analysis of crystallographic data and Grand Canonical Monte Carlo simulations provides insight into the two C3H8 binding sites in CMOM-7, both of which are driven by C-H···π and hydrogen bonding interactions.

19.
J Nutr Biochem ; 125: 109554, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38142716

RESUMO

Substantial evidence suggest that chronic consumption of high-fat diets (HFDs) can lead to obesity, abnormal metabolism, as well as cognitive impairment. Molecular and cellular changes regarding hippocampal dysfunctions have been identified in multiple HFD animal models. Therefore, in-depth identification of expression changes of hippocampal proteins is critical for understanding the mechanism of HFD-induced cognitive deficits. In this study, we fed 3-week-old male mice with HFD for 3 months to generate obese mice who exhibit systemic metabolic abnormality and learning and memory decline. Using an iTRAQ-labeled proteomic analysis, we identified a total of 82 differentially expressed proteins (DEPs) in the hippocampus upon HFD with 35 up-regulated proteins and 47 down-regulated proteins. Functional enrichment indicated that these DEPs were predominantly enriched in regulation of catabolic process, dendritic shaft, neuron projection morphogenesis and GTPase regulator activity. Protein-protein interaction enrichment showed that the DEPs are mostly enriched in postsynaptic functions; and of them, six proteins (i.e., DLG3, SYNGAP1, DCLK1, GRIA4, GRIP1, and ARHGAP32) were involved in several functional assemblies of the postsynaptic density including G-protein signaling, scaffolding and adaptor, kinase and AMPA signaling, respectively. Collectively, our findings suggest that these DEPs upon HFD might contribute to memory decline by disturbing neuronal and postsynaptic functions in the hippocampus.


Assuntos
Dieta Hiperlipídica , Proteômica , Camundongos , Masculino , Animais , Dieta Hiperlipídica/efeitos adversos , Camundongos Obesos , Transtornos da Memória/etiologia , Transtornos da Memória/metabolismo , Hipocampo/metabolismo , Camundongos Endogâmicos C57BL
20.
Chem Mater ; 35(23): 10001-10008, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38107195

RESUMO

Separation of the C8 aromatic isomers, xylenes (PX, MX, and OX) and ethylbenzene (EB), is important to the petrochemical industry. Whereas physisorptive separation is an energy-efficient alternative to current processes, such as distillation, physisorbents do not generally exhibit strong C8 selectivity. Herein, we report the mixed-linker square lattice (sql) coordination network [Zn2(sba)2(bis)]n·mDMF (sql-4,5-Zn, H2sba or 4 = 4,4'-sulfonyldibenzoic acid, bis or 5 = trans-4,4'-bis(1-imidazolyl)stilbene) and its C8 sorption properties. sql-4,5-Zn was found to exhibit high uptake capacity for liquid C8 aromatics (∼20.2 wt %), and to the best of our knowledge, it is the first sorbent to exhibit selectivity for PX, EB, and MX over OX for binary, ternary, and quaternary mixtures from gas chromatography. Single-crystal structures of narrow-pore, intermediate-pore, and large-pore phases provided insight into the phase transformations, which were enabled by flexibility of the linker ligands and changes in the square grid geometry and interlayer distances. This work adds to the library of two-dimensional coordination networks that exhibit high uptake, thanks to clay-like expansion, and strong selectivity, thanks to shape-selective binding sites, for C8 isomers.

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