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1.
PLoS Pathog ; 19(7): e1011556, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37498977

RESUMO

Although alveolar macrophages (AMs) play important roles in preventing and eliminating pulmonary infections, little is known about their regulation in healthy animals. Since exposure to LPS often renders cells hyporesponsive to subsequent LPS exposures ("tolerant"), we tested the hypothesis that LPS produced in the intestine reaches the lungs and stimulates AMs, rendering them tolerant. We found that resting AMs were more likely to be tolerant in mice lacking acyloxyacyl hydrolase (AOAH), the host lipase that degrades and inactivates LPS; isolated Aoah-/- AMs were less responsive to LPS stimulation and less phagocytic than were Aoah+/+ AMs. Upon innate stimulation in the airways, Aoah-/- mice had reduced epithelium- and macrophage-derived chemokine/cytokine production. Aoah-/- mice also developed greater and more prolonged loss of body weight and higher bacterial burdens after pulmonary challenge with Pseudomonas aeruginosa than did wildtype mice. We also found that bloodborne or intrarectally-administered LPS desensitized ("tolerized") AMs while antimicrobial drug treatment that reduced intestinal commensal Gram-negative bacterial abundance largely restored the innate responsiveness of Aoah-/- AMs. Confirming the role of LPS stimulation, the absence of TLR4 prevented Aoah-/- AM tolerance. We conclude that commensal LPSs may stimulate and desensitize (tolerize) alveolar macrophages in a TLR4-dependent manner and compromise pulmonary immunity. By inactivating LPS in the intestine, AOAH promotes antibacterial host defenses in the lung.


Assuntos
Hidrolases de Éster Carboxílico , Macrófagos Alveolares , Animais , Camundongos , Lipopolissacarídeos/toxicidade , Pulmão , Macrófagos Alveolares/imunologia , Receptor 4 Toll-Like , Hidrolases de Éster Carboxílico/metabolismo
2.
Nano Lett ; 24(9): 2912-2920, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38391386

RESUMO

Nanozymes with peroxidase-like activity have been extensively studied for colorimetric biosensing. However, their catalytic activity and specificity still lag far behind those of natural enzymes, which significantly affects the accuracy and sensitivity of colorimetric biosensing. To address this issue, we design PdSn nanozymes with selectively enhanced peroxidase-like activity, which improves the sensitivity and accuracy of a colorimetric immunoassay. The peroxidase-like activity of PdSn nanozymes is significantly higher than that of Pd nanozymes. Theoretical calculations reveal that the p-d orbital hybridization of Pd and Sn not only results in an upward shift of the d-band center to enhance hydrogen peroxide (H2O2) adsorption but also regulates the O-O bonding strength of H2O2 to achieve selective H2O2 activation. Ultimately, the nanozyme-linked immunosorbent assay has been successfully developed to sensitively and accurately detect the prostate-specific antigen (PSA), achieving a low detection limit of 1.696 pg mL-1. This work demonstrates a promising approach for detecting PSA in a clinical diagnosis.


Assuntos
Técnicas Biossensoriais , Peróxido de Hidrogênio , Masculino , Humanos , Antígeno Prostático Específico , Imunoensaio/métodos , Antioxidantes , Peroxidases , Colorimetria/métodos , Técnicas Biossensoriais/métodos
3.
Small ; 20(7): e2303946, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37806767

RESUMO

The key to increasing the rate of oxygen evolution reaction (OER) lies in accelerated four-electron dynamics, while the key to facilitating the development of supercapacitors lies in the design of electrode materials. This paper synthesized manganese-iron Prussian blue (MnFe-PBA@IF) at room temperature, and hexagonal concave structures w ere prepared using a fast-reducing matrix. Interestingly, MnFe-PBA@IF has an amorphous structure favorable to exposing more active surfaces. According to Gibbs free energy calculations on MnFe-PBA, charge depletion of manganese atoms can greatly enhance the adsorption of electron-rich oxygen-containing groups on the surface. Furthermore, the overpotential in 1 m KOH is 280 mV. Also, it can be used as a supercapacitor with a stable operating voltage range of -0.9-0 V and a specific capacity of 1260 F g-1 . This work provides new insights into the synthesis of OER catalysts for Prussian blue ferromanganese at room temperature. Non-gold-bonded adsorption, highly active metal centers and active surfaces are the underlying reasons for the superior performance of supercapacitors. Therefore, Prussian blue with good energy storage performance and high active surface can be used as multifunctional energy storage and conversion electrodes.

4.
Inorg Chem ; 63(14): 6396-6407, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38528328

RESUMO

Indium phosphide (InP) quantum dots (QDs) have become the most recognized prospect to be less-toxic surrogates for Cd-based optoelectronic systems. Due to the particularly dangling bonds (DBs) and the undesirable oxides, the photoluminescence performance and stability of InP QDs remain to be improved. Previous investigations largely focus on eliminating P-DBs and resultant surface oxidation states; however, little attention has been paid to the adverse effects of the surface In-DBs on InP QDs. This work demonstrates a facile one-step surface peeling and passivation treatment method for both In- and P-DBs for InP QDs. Meanwhile, the surface treatment may also effectively support the encapsulation of the ZnSe shell. Finally, the generated InP/ZnSe QDs display a narrower full width at half-maximum (fwhm) of ∼48 nm, higher photoluminescence quantum yields (PLQYs) of ∼70%, and superior stability. This work enlarges the surface chemistry engineering consideration of InP QDs and considerably promotes the development of efficient and stable optoelectronic devices.

5.
Immunol Invest ; 53(4): 574-585, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38329477

RESUMO

BACKGROUND: Complex pathophysiological the specific mechanism of sepsis on CD4+ T-cell responses is less well understood. IL1 receptor accessory protein (IL1RAP) was found to be involved in activating host immune responses. METHOD: Cecum ligation and puncture (CLP) was utilized to build a mouse sepsis model. The experiment was randomly divided into four groups: Sham, CLP, CLP + shNC, and CLP + shIL1RAP group. RESULTS: qRT-PCR suggested mRNA levels of IL1RAP were decreased when IL1RAP was knocked down with the mRNA levels of IL-1ß, NF-κB, and p38 decreased. Histopathology showed severe pathological damage with alveolar integrity lost, red blood cells in the alveoli, massive inflammatory cell infiltration, and the alveolar wall was thickening in the CLP group. The inflammatory cytokine levels of TNF-α, IL-1ß, and IFN-γ were elevated in CLP mice by ELISA. The counts of CD4+ T cells were decreased in sepsis mice in peripheral blood, spleen, and BALF by flow cytometry. However, the above was blocked down when using shIL1RAP. Western blot suggested sh IL1RAP inhibited IL-1ß, NF-κB, and p38 protein expressions. CONCLUSIONS: We defined IL1RAP as a new target gene through NF-κB/MAPK pathways regulating CD4+ T lymphocyte differentiation mediated the progression of sepsis, which is potentially exploitable for immunotherapy.


Assuntos
Linfócitos T CD4-Positivos , Diferenciação Celular , Modelos Animais de Doenças , NF-kappa B , Sepse , Baço , Animais , Feminino , Masculino , Camundongos , Linfócitos T CD4-Positivos/imunologia , Citocinas/metabolismo , Pulmão/patologia , Pulmão/imunologia , Lesão Pulmonar/imunologia , Lesão Pulmonar/etiologia , Lesão Pulmonar/patologia , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Sepse/imunologia , Sepse/complicações , Transdução de Sinais , Baço/imunologia , Baço/patologia , Baço/metabolismo
6.
BMC Cardiovasc Disord ; 24(1): 86, 2024 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-38310240

RESUMO

OBJECTIVE: We aimed to explore the heterogeneity of neurons in heart failure with dilated cardiomyopathy (DCM). METHODS: Single-cell RNA sequencing (scRNA-seq) data of patients with DCM and chronic heart failure and healthy samples from GSE183852 dataset were downloaded from NCBI Gene Expression Omnibus, in which neuron data were extracted for investigation. Cell clustering analysis, differential expression analysis, trajectory analysis, and cell communication analysis were performed, and highly expressed genes in neurons from patients were used to construct a protein-protein interaction (PPI) network and validated by GSE120895 dataset. RESULTS: Neurons were divided into six subclusters involved in various biological processes and each subcluster owned its specific cell communication pathways. Neurons were differentiated into two branches along the pseudotime, one of which was differentiated into mature neurons, whereas another tended to be involved in the immune and inflammation response. Genes exhibited branch-specific differential expression patterns. FLNA, ITGA6, ITGA1, and MDK interacted more with other gene-product proteins in the PPI network. The differential expression of FLNA between DCM and control was validated. CONCLUSION: Neurons have significant heterogeneity in heart failure with DCM, and may be involved in the immune and inflammation response to heart failure.


Assuntos
Cardiomiopatia Dilatada , Insuficiência Cardíaca , Humanos , Cardiomiopatia Dilatada/diagnóstico , Cardiomiopatia Dilatada/genética , Cardiomiopatia Dilatada/metabolismo , Perfilação da Expressão Gênica , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/genética , Inflamação , Análise de Sequência de RNA , Neurônios/metabolismo
7.
Clin Sci (Lond) ; 137(22): 1753-1769, 2023 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-37921121

RESUMO

Sepsis is known to cause damage to the intestinal mucosa, leading to bacterial translocation, and exacerbation of both local and remote organ impairments. In the present study, fecal samples were collected from both septic and healthy individuals. Analysis through 16s rRNA sequencing of the fecal microbiota revealed that sepsis disrupts the balance of the gut microbial community. Recent research has highlighted the association of lipid metabolism with disease. By analyzing the fecal metabolome, four lipid metabolites that showed significant differences between the two groups were identified: PE (O-16:0/0:0), PE (17:0/0:0), PE (0:0/14:0), and PE (12:0/20:5 (5Z, 8Z, 11Z, 14Z, 17Z)). Notably, the serum levels of PE (0:0/14:0) were higher in the healthy group. Subsequent in vitro and in vivo experiments demonstrated the protective effects of this compound against sepsis-induced intestinal barrier damage. Label-free proteomic analysis showed significant differences in the expression levels of the aryl hydrocarbon receptor (AHR), a protein implicated in sepsis pathogenesis, between the LPS-Caco-2 and LPS-Caco-2 + PE (0:0/14:0) groups. Further analysis, with the help of Discovery Studio 3.5 software and co-immunoprecipitation assays, confirmed the direct interaction between AHR and PE (0:0/14:0). In the cecal ligation and puncture (CLP) model, treatment with PE (0:0 /14:0) was found to up-regulate the expression of tight junction proteins through the AHR/Cytochrome P450, family 1, subfamily A, and polypeptide 1 (CYP1A1) pathway. This highlights the potential therapeutic use of PE (0:0/14:0) in addressing sepsis-induced intestinal barrier damage.


Assuntos
Microbioma Gastrointestinal , Sepse , Humanos , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A1/metabolismo , Citocromo P-450 CYP1A1/farmacologia , Células CACO-2 , Microbioma Gastrointestinal/fisiologia , Receptores de Hidrocarboneto Arílico/genética , Receptores de Hidrocarboneto Arílico/metabolismo , Receptores de Hidrocarboneto Arílico/uso terapêutico , RNA Ribossômico 16S , Lipopolissacarídeos/farmacologia , Proteômica , Sepse/metabolismo , Mucosa Intestinal/metabolismo
8.
Molecules ; 28(13)2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37446887

RESUMO

Folic acid (FA) has shown great potential in the fields of targeted drug delivery and disease diagnosis due to its highly tumor-targeting nature, biocompatibility, and low cost. However, FA is generally introduced in targeted drug delivery systems through macromolecular linkage via complex synthetic processes, resulting in lower yields and high costs. In this work, we report a general protocol for synthesizing thiolated folate derivatives. The small molecule thiolated folate (TFa) was first synthesized with a purity higher than 98.20%. First, S-S-containing diol was synthesized with a purity higher than 99.44 through a newly developed green oxidation protocol, which was carried out in water with no catalyst. Then, folic acid was modified using the diol through esterification, and TFa was finally synthesized by breaking the disulfide bond. Further, the synthesized TFa was utilized to modify silver nanoparticles. The results showed that TFa could be easily bonded to metal particles. The protocol could be extended to the synthesis of a series of thiolated derivatives of folate, such as mercaptohexyl folate, mercaptoundecyl folate, etc., which would greatly benefit the biological applications of FA.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Neoplasias , Humanos , Ácido Fólico/química , Prata , Sistemas de Liberação de Medicamentos , Nanopartículas/química , Linhagem Celular Tumoral
9.
Pharm Biol ; 61(1): 630-638, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37036063

RESUMO

CONTEXT: Gastrointestinal symptoms are a common complication of influenza virus infection in children, which the gut-lung axis become involved in its biological progress. The protective effect of 999 XiaoErGanMao granules (XEGMG) on multi-organ injury in viral pneumonia remains unclear. OBJECTIVE: To investigate the therapeutic effect of XEGMG on lungs and intestines injury in A/FM/1/47 (H1N1) influenza virus-infected mice. MATERIALS AND METHODS: Male BALB/c mice were infected with the 2LD50 H1N1 influenza virus and then treated with XEGMG (6 or 12 g/kg) intragastrically once a day for 4 days. The lung and colon samples were then collected for pathological observation, and assays for inflammatory cytokines and intestinal barrier. Mouse feces were collected to evaluate the intestinal microbiota. RESULTS: Treating with XEGMG (12 g/kg) can mitigate body weight loss caused by 2LD50 H1N1 infection. It can also reduce lung index and pathological damage with the decreased inflammatory cytokines such as IL-6 and IL-1ß. Furthermore, XEGMG (12 g/kg) can maintain the goblet cell number in the colons to protect the intestinal barrier and regulate the major flora such as Firmicutes, Bacteroidetes, and Muribaculaceae back to normal. Meanwhile, the expression of IL-17A in the colon tissues was significantly lower in the group of XEGMG (6, 12 g/kg) compared to H1N1 group. DISCUSSION AND CONCLUSIONS: XEGMG can protect against H1N1 invasion involved in gut-lung axis regulation. The results provide new evidence for the protective effect of XEGMG, which is beneficial to vulnerable children.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Vírus da Influenza A , Masculino , Animais , Camundongos , Vírus da Influenza A/metabolismo , Pulmão , Citocinas/metabolismo , Intestinos , Camundongos Endogâmicos BALB C
10.
IUBMB Life ; 74(11): 1070-1080, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35859520

RESUMO

Immunosuppression mediated by CD4+ T cell apoptosis and dysfunction is a key factor in promoting the progression of sepsis. Endoplasmic reticulum (ER) stress participates in the apoptosis and dysfunction of immune cells. We aimed to investigate the role of ER stress inhibition in CD4+ T cells in both in vitro and in vivo models of sepsis. In vitro model of sepsis was established with lipopolysaccharide (LPS) and the rat model of sepsis was established using cecal ligation and puncture (CLP). After the LPS treatment or CLP, ER stress inhibitors including 4-PBA, SNJ-1945, and SP600125 were used to treat cells or rats, and the CD4+ T cells were obtained by magnetic bead sorting. The effects of ER stress inhibitors on apoptosis and the function of CD4+ T cells were evaluated. After the LPS stimulation or CLP, the levels of ER stress and downstream markers (PERK, eIF2α, IRE-1α, ATF6, ATF4, XBP-1 s, GRP78, CHOP, and p-JNK) were increased in CD4+ T cells at the beginning of sepsis. Meanwhile, the number of apoptotic CD4+ T cells markedly increased. In addition, sepsis impaired the function of CD4+ T cells, manifested by the increased population of Th1, Th2, Th17, and Treg, as well as the production of TNF-α, interleukin (IL)-6, IL-4, and IL-10. However, inhibitors of ER stress, JNK, and calpain all decreased the induction of Th1 and Th17, enhanced the increase of Th2 and Treg, decreased the production of TNF-α and IL-6, and enhanced the production of IL-4 and IL-10. Our findings indicate that ER stress inhibitors may play a protective role by reducing CD4+ T cell apoptosis and maintaining CD4+ T cell function, which may be useful for enhancing the immune function and poor prognosis of patients with sepsis.


Assuntos
Estresse do Retículo Endoplasmático , Sepse , Ratos , Animais , Lipopolissacarídeos/toxicidade , Interleucina-10/genética , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-6/metabolismo , Calpaína/metabolismo , Calpaína/farmacologia , Interleucina-4 , Apoptose , Sepse/metabolismo , Linfócitos T CD4-Positivos/metabolismo
11.
Biochem Genet ; 60(6): 2000-2014, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35190931

RESUMO

This study aims to investigate the effects of miR-29b-3p on the inflammation injury of human umbilical vein endothelial cells (HUVECs) induced by lipopolysaccharide (LPS) and explore the underlying mechanisms. The effects of different concentrations of LPS (0, 1, 5 and 10 µg/mL) on inflammation injury in HUVECs are detected by ELISA, CCK-8, EdU, flow cytometry and western blot analyses to determine the optimal stimulus concentration. After stimulating HUVECs with 10 µg/mL LPS, the expression levels of miR-29b-3p are detected, and the effects of miR-29b-3p on inflammation injury are detected by ELISA, CCK-8, EdU, flow cytometry and western blot analyses. Bioinformatic analysis, luciferase reporter assay and confirmatory experiments are applied to identify the target gene bound with miR-29b-3p. Rescue experiments have verified the roles of miR-29b-3p and the target gene in inflammation injury. We found that pro-inflammatory factor was increased, apoptosis was promoted, and cell proliferation was inhibited after the treatment of LPS in HUVECs. Overexpression of miR-29b-3p inhibited LPS-induced inflammatory response and apoptosis while promoting proliferation in HUVECs. Besides, bioinformatics analysis indicated that SEC23A was the target gene of miR-29b-3p and the confirmatory experiments showed that SEC23A was negatively correlated with miR-29b-3p and positively correlated with LPS concentration. Rescue experiments revealed that overexpression of SEC23A partially enhanced the inflammation injury effects in LPS-induced HUVECs with overexpression of miR-29b-3p. Hence, miR-29b-3p repressed inflammatory response, cell apoptosis and promoted cell proliferation in LPS-induced HUVECs by targeting SEC23A, providing a potential target for treating sepsis.


Assuntos
MicroRNAs , Proteínas de Transporte Vesicular , Humanos , Apoptose/genética , Células Endoteliais da Veia Umbilical Humana/metabolismo , Inflamação/induzido quimicamente , Inflamação/genética , Lipopolissacarídeos/toxicidade , MicroRNAs/genética , Proteínas de Transporte Vesicular/genética
12.
Int J Mol Sci ; 23(12)2022 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-35743042

RESUMO

The clinical use of anticancer drugs necessitates new technologies for their safe, sensitive, and selective detection. In this article, lanthanide (Eu3+ and Tb3+)-loaded γ-cyclodextrin nano-aggregates (ECA and TCA) are reported, which sensitively detects the anticancer drug irinotecan by fluorescence intensity changes. Fluorescent lanthanide (Eu3+ and Tb3+) complexes exhibit high fluorescence intensity, narrow and distinct emission bands, long fluorescence lifetime, and insensitivity to photobleaching. However, these lanthanide (Eu3+ and Tb3+) complexes are essentially hydrophobic, toxic, and non-biocompatible. Lanthanide (Eu3+ and Tb3+) complexes were loaded into naturally hydrophilic γ-cyclodextrin to form fluorescent nano-aggregates. The biological nontoxicity and cytocompatibility of ECA and TCA fluorescent nanoparticles were demonstrated by cytotoxicity experiments. The ECA and TCA fluorescence nanosensors can detect irinotecan selectively and sensitively through the change of fluorescence intensity, with detection limits of 6.80 µM and 2.89 µM, respectively. ECA can safely detect irinotecan in the cellular environment, while TCA can detect irinotecan intracellularly and is suitable for cell labeling.


Assuntos
Antineoplásicos , Elementos da Série dos Lantanídeos , gama-Ciclodextrinas , Antineoplásicos/farmacologia , Irinotecano , Elementos da Série dos Lantanídeos/química
13.
Microb Pathog ; 154: 104826, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33689815

RESUMO

Candida albicans is an opportunistic fungus that can threaten life especially in patients with candidemia. The morbidity and mortality of candidemia originating from a central venous catheter (CVC) and illicit intravenous drug use (IVDU) are increasing. However, the mechanism underlying the bloodborne C. albicans infection remains unclear. Herein, we evaluated the gut microbiome, metabolites and intestinal mucosa by constructing the mouse models with candidemia. Model mice were injected with C. albicans via tail vein. Control mice underwent sham procedures. We observed basic life characteristics, intestinal damage-related alterations using hematoxylin and eosin (H&E) staining, intestinal tight junction protein levels, and intestinal permeability in these mice. Fecal samples were analyzed by performing 16S rRNA gene sequencing of the microbiota and LC-MS metabolomics to reveal the perturbations in intestinal flora and metabolism exacerbating intestinal damage. Weight loss, a decreased survival rate, C. albicans infection spread, and colonic epithelial damage occurred in the model group. Furthermore, the intestinal flora abundance was reduced. Several probiotics, such as Lactobacillus, and butyrate-producing bacteria, including Roseburia, Lachnospiraceae, and Clostridia, were depleted, and some pathogenic bacteria, such as Escherichia-Shigella and Proteus, belonging to the Proteobacteria phylum, and the inflammation mediators Ruminococcus and Parabacteroides were enriched in model mice. Multiple differentially altered metabolic pathways were observed and mainly related to bile acid, arachidonic acid, bile secretion, and arachidonic acid metabolism. This study illustrated the effects of a bloodborne C. albicans on the intestinal microbiota, metabolites, and intestinal barrier, which may provide new insights into tests or treatments for candidemia originating from CVC or IVDU.


Assuntos
Microbioma Gastrointestinal , Animais , Candida albicans , Humanos , Mucosa Intestinal , Intestinos , Metaboloma , Camundongos , RNA Ribossômico 16S/genética
14.
Nanotechnology ; 32(22)2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33321482

RESUMO

The composite particles composed of quantum dots coated with silica and grafted with copolymer of polyethylene glycol and low molecular weight polyethylene terephthalate (QDs@SiO2-PEG-LMPET) are synthesized. The internal QDs provide luminescent performance and combine with SiO2to form QDs@SiO2with good dispersion to solve the defect that small-sized SiO2is prone to agglomerate. The block polymer LMPET-PEG grafted on the surface can make the composite particles better compatible with the PET matrix. In summary, QDs@SiO2-PEG-LMPET not only play the same role as SiO2to enhance the crystallization performance of PET matrix, but also provide stable luminescence performance, which is multifunctional additive with broad application prospects.

15.
Macromol Rapid Commun ; 42(10): e2000757, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33870582

RESUMO

With the significant progress of low bandgap non-fullerene acceptors, the development of wide bandgap (WBG) donors possessing ideal complementary absorption is of crucial importance to further enhance the photovoltaic performance of organic solar cells. An ideal strategy to design WBG donors is to down-shift the highest occupied molecular orbital (HOMO) and up-shift the lowest unoccupied molecular orbital (LUMO). A properly low-lying HOMO of the donor is favorable to obtaining a high open-circuit voltage, and a properly high-lying LUMO of the donor is conductive to efficient exciton dissociation. This work provides a new strategy to enlarge the bandgap of a polymer with simultaneously decreased HOMO and increased LUMO by increasing the polymer backbone curvature. The polymer PIDT-fDTBT with a large molecular backbone curvature shows a decreased HOMO of -5.38 eV and a prominently increased LUMO of -3.35 eV relative to the linear polymer PIDT-DTBT (EHOMO = -5.30 eV, ELUMO = -3.55 eV). The optical bandgap of PIDT-fDTBT is obviously broadened from 1.75 to 2.03 eV. This work demonstrates that increasing the polymer backbone curvature can effectively broaden the bandgap by simultaneously decreasing HOMO and increasing LUMO, which may guide the design of WBG conjugated materials.


Assuntos
Energia Solar , Condutividade Elétrica , Polímeros
16.
Clin Infect Dis ; 71(Suppl 4): S337-S362, 2020 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-33367581

RESUMO

The Chinese guidelines for IAI presented here were developed by a panel that included experts from the fields of surgery, critical care, microbiology, infection control, pharmacology, and evidence-based medicine. All questions were structured in population, intervention, comparison, and outcomes format, and evidence profiles were generated. Recommendations were generated following the principles of the Grading of Recommendations Assessment, Development, and Evaluation system or Best Practice Statement (BPS), when applicable. The final guidelines include 45 graded recommendations and 17 BPSs, including the classification of disease severity, diagnosis, source control, antimicrobial therapy, microbiologic evaluation, nutritional therapy, other supportive therapies, diagnosis and management of specific IAIs, and recognition and management of source control failure. Recommendations on fluid resuscitation and organ support therapy could not be formulated and thus were not included. Accordingly, additional high-quality clinical studies should be performed in the future to address the clinicians' concerns.


Assuntos
Fístula , Infecções Intra-Abdominais , Cirurgiões , China , Cuidados Críticos , Humanos , Infecções Intra-Abdominais/diagnóstico , Infecções Intra-Abdominais/tratamento farmacológico
17.
Phys Chem Chem Phys ; 22(11): 6032-6057, 2020 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-32124882

RESUMO

Graphene-based membranes exhibit enormous potential in water desalination and purification because of their ultrathin structure, superhigh water flux, tunable physicochemical properties and precise ionic and molecular sieving performance. However, the transport behavior and mechanism of water, ions and other molecules across nanopores and nanocapillaries in the separation process, especially the confined mass transport, remain unclear, imposing severe limitation on many applications. Therefore, extensive experimental studies and theoretical calculation simulations have been carried out to investigate their unique structure and separation properties, particularly to explore the associated confined mass transport mechanism. Herein, an overview of the theory and simulation developments of graphene-based separation membranes based on confined mass transport is provided, attempting to open up an avenue for designing graphene-based materials as a new generation of separation membranes in the water purification field. This perspective focuses on five topics: (1) membrane transport models and simulation methods; (2) comparison between membrane simulations and experiments; (3) confined mass transport studies of graphene-based membranes with the assistance of molecular dynamics (MD) simulations; (4) fabrication of multifunctional composite membranes; and (5) future research trends in graphene-based membranes.

18.
Appl Opt ; 59(28): 9042-9050, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33104594

RESUMO

Sodium alginate (SA), as a natural marine biopolymer, possesses many merits such as super-easy accessibility from the ocean, low cost, nontoxicity, and no synthesis for practical application. For the chemical structure, SA has enough lone electron pairs of oxygen atoms in the backbone and short branched chains, which is expected to passivate oxygen vacancy on the surface of the ZnO cathode buffer layer to improve the photovoltaic performance. Herein, it was applied to modify the surface trap of the ZnO layer in fullerene and non-fullerene polymer solar cells (PSCs). The defects were successfully reduced, and the trap-assisted recombination decreased. In a PTB7-Th:PC71BM system, power conversion efficiency (PCE) was improved from 8.06% to 9.36%. In the PM6:IT-4F system, PCE was enhanced from 12.13% to 13.08%. The addition of SA did not destroy the stability of the device. Overall, this work demonstrates the potential for preparing devices with long-time stability and industrial manufacture of PSCs by using biological materials in the future.


Assuntos
Alginatos/química , Biopolímeros/química , Fontes de Energia Elétrica , Energia Solar , Óxido de Zinco/química , Desenho de Equipamento , Nanoestruturas/química
19.
Sci Technol Adv Mater ; 21(1): 726-736, 2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-33177954

RESUMO

The organic Eu3+-complex [Eu(TTA)3Phen] has been incorporated into the channels of surface-modified frustules from diatoms as a key material to absorb and convert UV-photons to visible luminescence. Systematic investigation results indicate that the organic Eu3+-complex encapsulated in the functionalized diatomite channels exhibits enhanced luminescence and longer lifetime, owning to the Eu(TTA)3Phen complex interacting with its surrounding silylating agents. The organic Eu3+-complex-anchored porous diatomite hybrid luminescent material was compounded with polyethylene terephthalate (PET) by using a mini-twin screw extruder to prepare a self-supporting film of the hybrid material. Besides, the UV absorption properties of the composite films were investigated. These films will potentially be related to the UV protection of photovoltaic devices.

20.
Small ; 15(47): e1903977, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31608586

RESUMO

Black phosphorous quantum dots (BPQDs) possess ambipolar charge transport, high mobility, and a tunable direct bandgap. Here, liquid-exfoliated BPQDs are used as interlayers to modify both the electron transport layer and hole transport layer in organic solar cells (OSCs). The incorporation of BPQDs is beneficial to the formation of a cascade band structure and electron/hole transfer and extraction. The power conversion efficiency of the BPQDs-incorporated OSC based on PTB7-Th:FOIC blend is enhanced from 11.8% to 13.1%. In addition, power conversion efficiency enhancement is also achieved for other nonfullerene and fullerene-based devices, demonstrating the universality of this interlayer methodology.

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