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1.
J Neuroinflammation ; 21(1): 96, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38627764

RESUMO

BACKGROUND: Gasdermin D (GSDMD)-mediated pyroptotic cell death is implicated in the pathogenesis of cognitive deficits in sepsis-associated encephalopathy (SAE), yet the underlying mechanisms remain largely unclear. Dynamin-related protein 1 (Drp1) facilitates mitochondrial fission and ensures quality control to maintain cellular homeostasis during infection. This study aimed to investigate the potential role of the GSDMD/Drp1 signaling pathway in cognitive impairments in a mouse model of SAE. METHODS: C57BL/6 male mice were subjected to cecal ligation and puncture (CLP) to establish an animal model of SAE. In the interventional study, mice were treated with the GSDMD inhibitor necrosulfonamide (NSA) or the Drp1 inhibitor mitochondrial division inhibitor-1 (Mdivi-1). Surviving mice underwent behavioral tests, and hippocampal tissues were harvested for histological analysis and biochemical assays at corresponding time points. Haematoxylin-eosin staining and TUNEL assays were used to evaluate neuronal damage. Golgi staining was used to detect synaptic dendritic spine density. Additionally, transmission electron microscopy was performed to assess mitochondrial and synaptic morphology in the hippocampus. Local field potential recordings were conducted to detect network oscillations in the hippocampus. RESULTS: CLP induced the activation of GSDMD, an upregulation of Drp1, leading to associated mitochondrial impairment, neuroinflammation, as well as neuronal and synaptic damage. Consequently, these effects resulted in a reduction in neural oscillations in the hippocampus and significant learning and memory deficits in the mice. Notably, treatment with NSA or Mdivi-1 effectively prevented these GSDMD-mediated abnormalities. CONCLUSIONS: Our data indicate that the GSDMD/Drp1 signaling pathway is involved in cognitive deficits in a mouse model of SAE. Inhibiting GSDMD or Drp1 emerges as a potential therapeutic strategy to alleviate the observed synaptic damages and network oscillations abnormalities in the hippocampus of SAE mice.


Assuntos
Disfunção Cognitiva , Encefalopatia Associada a Sepse , Sepse , Animais , Masculino , Camundongos , Disfunção Cognitiva/metabolismo , Dinaminas/metabolismo , Hipocampo/metabolismo , Camundongos Endogâmicos C57BL , Sepse/patologia , Encefalopatia Associada a Sepse/metabolismo , Transdução de Sinais
2.
Acta Pharmacol Sin ; 45(6): 1287-1304, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38360930

RESUMO

HER2-positive (HER2+) metastatic breast cancer (mBC) is highly aggressive and a major threat to human health. Despite the significant improvement in patients' prognosis given the drug development efforts during the past several decades, many clinical questions still remain to be addressed such as efficacy when combining different therapeutic modalities, best treatment sequences, interindividual variability as well as resistance and potential coping strategies. To better answer these questions, we developed a mechanistic quantitative systems pharmacology model of the pathophysiology of HER2+ mBC that was extensively calibrated and validated against multiscale data to quantitatively predict and characterize the signal transduction and preclinical tumor growth kinetics under different therapeutic interventions. Focusing on the second-line treatment for HER2+ mBC, e.g., antibody-drug conjugates (ADC), small molecule inhibitors/TKI and chemotherapy, the model accurately predicted the efficacy of various drug combinations and dosing regimens at the in vitro and in vivo levels. Sensitivity analyses and subsequent heterogeneous phenotype simulations revealed important insights into the design of new drug combinations to effectively overcome various resistance scenarios in HER2+ mBC treatments. In addition, the model predicted a better efficacy of the new TKI plus ADC combination which can potentially reduce drug dosage and toxicity, while it also shed light on the optimal treatment ordering of ADC versus TKI plus capecitabine regimens, and these findings were validated by new in vivo experiments. Our model is the first that mechanistically integrates multiple key drug modalities in HER2+ mBC research and it can serve as a high-throughput computational platform to guide future model-informed drug development and clinical translation.


Assuntos
Neoplasias da Mama , Receptor ErbB-2 , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Humanos , Feminino , Receptor ErbB-2/metabolismo , Receptor ErbB-2/antagonistas & inibidores , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Inibidores de Proteínas Quinases/farmacologia , Imunoconjugados/uso terapêutico , Imunoconjugados/farmacologia , Farmacologia em Rede , Modelos Biológicos , Antineoplásicos/uso terapêutico , Antineoplásicos/administração & dosagem , Camundongos , Linhagem Celular Tumoral , Metástase Neoplásica
3.
Antonie Van Leeuwenhoek ; 117(1): 101, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39008162

RESUMO

Two novel Gram-stain-negative, aerobic, and non-motile strains, designated FZY0004T and YYF002T, were isolated from an agar-degrading co-culture, which was obtained from seawater of the intertidal zone of Yancheng City, the Yellow Sea of China. Strain FZY0004T optimally grew at 28 °C, pH 7.0, and 2-6% NaCl, while strain YYF002T optimally grew at 28 °C, pH 7.5, and 2-4% NaCl. Strain FZY0004T possessed Q-9 as the major respiratory quinone, and its major fatty acids (> 10%) were summed feature 8 (C18:1 ω7c), C16:0, and summed feature 3 (C16:1 ω7c/C16:1 ω6c). The polar lipids identified in strain FZY0004T were phosphatidylethanolamine (PE), phosphatidylglycerol (PG), and several unidentified phospholipids (PL) and lipids (L). On the other hand, strain YYF002T had MK-6 as the predominant respiratory quinone and its major fatty acids consisted of iso-C15:0, iso-C15:1 G, and iso-C15:0 3-OH. The polar lipids identified in strain YYF002T were aminolipid (AL), PE, and several unidentified lipids. Strain FZY0004T shared 99.5% 16S rRNA gene sequence similarity and 90.1% average nucleotide identity (ANI) with T. povalilytica Zumi 95T, and strain YYF002T shared 99.2% 16S rRNA gene sequence similarity and 88.2% ANI with W. poriferorum JCM 12885T. The genomic DNA G + C contents of strains FZY0004T and YYF002T were 54.5% and 33.5%, respectively. The phylogenetic, phenotypic, and physiological characteristics permitted the distinction of the two strains from their neighbors, and we thus propose the names Thalassospira aquimaris sp. nov. (type strain FZY0004T = JCM 35895T = MCCC 1K08380T) and Winogradskyella marincola sp. nov. (type strain YYF002T = JCM 35950T = MCCC 1K08382T).


Assuntos
Ágar , DNA Bacteriano , Ácidos Graxos , Filogenia , RNA Ribossômico 16S , Água do Mar , RNA Ribossômico 16S/genética , Água do Mar/microbiologia , DNA Bacteriano/genética , Ágar/metabolismo , Ácidos Graxos/metabolismo , Composição de Bases , Técnicas de Tipagem Bacteriana , China , Fosfolipídeos/metabolismo , Técnicas de Cocultura , Análise de Sequência de DNA
4.
J Nanobiotechnology ; 22(1): 546, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39237931

RESUMO

Lung cancer, predominantly non-small cell lung cancer (NSCLC), remains a significant global health challenge, with limited therapeutic options for patients with KRAS-mutated tumors. Herein, a copper-based metal-organic framework (Cu-MOF) was applied as a novel cuproptosis-mediated nanoplatform for lung cancer therapy. Cu-MOF would disassemble and liberate copper ions under the acidic microenvironment of lysosomes of cancer cells, initiating a cascade of cellular events. The released copper ions catalyzes the Fenton reaction, generating hydroxyl radicals that induce oxidative damage, leading to cytoskeletal disruption and activation of caspase-3, ultimately triggering apoptosis. Simultaneously, with the mediation of the key regulatory factor FDX1, we found that the copper ions binding to the mitochondrial protein DLAT could result in the loss of iron-sulfur cluster proteins and aggregation of lipoylated proteins, which culminated in proteotoxic stress-induced cuproptosis. The pronounced anti-tumor effects of Cu-MOF with apoptosis and cuproptosis were confirmed both in vitro and in vivo experiments. Such dual induction of apoptosis and cuproptosis by Cu-MOF presents a promising therapeutic strategy for NSCLC, particularly for KRAS-mutated tumors, and expands potential applications of Cu-based nanomateirals for other cancers.


Assuntos
Apoptose , Cobre , Neoplasias Pulmonares , Estruturas Metalorgânicas , Cobre/química , Cobre/farmacologia , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/farmacologia , Humanos , Apoptose/efeitos dos fármacos , Animais , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Camundongos , Linhagem Celular Tumoral , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Antineoplásicos/farmacologia , Antineoplásicos/química , Camundongos Nus , Camundongos Endogâmicos BALB C
5.
Curr Microbiol ; 81(11): 392, 2024 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-39369359

RESUMO

A Gram-staining negative, non-motile, rod-shaped, oxidase negative and catalase positive strain WL0021T was isolated from cricket (Gryllus chinensis) living in the campus of Hohai University. Strain WL0021T was characterized utilizing a polyphasic taxonomy approach. The major fatty acids (> 5%) for strain WL0021T were C16:0 and summed feature 8, and the major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, phospholipid, two aminolipids, and an unidentified polar lipid. Ubiquinone-10 was detected as the predominant respiratory quinone. The results of 16S rRNA gene phylogenetic analyses revealed that strain WL0021T had the highest sequence similarity of 95.3% to Microvirga flavescens c27j1T and strain WL0021T formed a distinct linage within the family Methylobacteriaceae in the phylogenetic trees. Whole genomic DNA G+C content was 48.3%. Combined with the results from this study, strain WL0021T should represent a novel genus in the family Methylobacteriaceae, for which the name Hohaiivirga grylli gen. nov., sp. nov. (type strain WL0021T=GDMCC 1.2420T =JCM 34655T=MCCC 1K05886T) is proposed.


Assuntos
Composição de Bases , DNA Bacteriano , Ácidos Graxos , Gryllidae , Filogenia , RNA Ribossômico 16S , Gryllidae/microbiologia , RNA Ribossômico 16S/genética , Animais , Ácidos Graxos/química , Ácidos Graxos/análise , DNA Bacteriano/genética , Fosfolipídeos/análise , Técnicas de Tipagem Bacteriana , Análise de Sequência de DNA , Ubiquinona/química
6.
Sheng Li Xue Bao ; 76(3): 407-417, 2024 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-38939935

RESUMO

Noise, as an unavoidable stress (pressure) source in the modern life, affects animals in many ways, both behaviorally and physiologically. Behavioral changes may be driven by changes in hormone secretion in animals. When animals face with noise stress, the neuroendocrine systems, mainly the hypothalamic-pituitary-adrenal (HPA) axis, are activated, which promotes the secretion and release of stress hormones, and then leads to a series of behavioral changes. The behavioral changes can be easily observed, but the changes in physiological indicators such as hormone levels need to be accurately measured. Currently, many studies have measured the variations of stress hormone levels in animals under different noise conditions. Taking glucocorticoid as an example, this paper summarizes the different measurement methods of stress hormones, especially the non-invasive measurement methods, and compares the advantages and shortcomings of them. It provides a variety of measurement choices for the study of related issues, and also helps us to further understand the sources of animal stress, in order to provide a better habitat for animals.


Assuntos
Sistema Hipotálamo-Hipofisário , Ruído , Sistema Hipófise-Suprarrenal , Estresse Fisiológico , Animais , Sistema Hipotálamo-Hipofisário/fisiologia , Sistema Hipófise-Suprarrenal/fisiologia , Estresse Fisiológico/fisiologia , Glucocorticoides/metabolismo , Estresse Psicológico/fisiopatologia
7.
Arch Microbiol ; 205(2): 58, 2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36622427

RESUMO

A Gram-stain-negative, non-motile and coccoid bacterial strain, designated XHP0099T, was isolated from the coastal water of the Yellow Sea, China. Growth occurred at 20-37 â„ƒ (optimum, 28 â„ƒ), pH 5.0-9.0 (optimum, pH 7.0-8.0), and with 0-7.0% NaCl (optimum, 2.0-3.0%). Phylogenetic analysis based on 16S rRNA gene sequences showed that strain XHP0099T was related to members of the genus Paracoccus and shared the highest sequence similarity with "P. siganidrum" M26 (98.2%), followed by P. alkanivorans 4-2 T (97.6%) and P. alkenifer DSM 11593 T (97.4%). The average nucleotide identity, amino acid identity, and digital DNA-DNA hybridization values of strain XHP0099T against related members in the genus Paracoccus were below the cut-off points proposed for the delineation of a novel species. The major cellular fatty acids (> 10%) were summed feature 8 (C18:1 ω7c/C18:1 ω6c), and C18:0. The major isoprenoid quinone was Q-10 and the polar lipids contained diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), phosphatidylethanolamine (PE), phosphatidylcholine (PC), aminolipid (AL) and unidentified polar lipids (L). The G + C content of the genomic DNA of strain XHP0099T was 66.0%. Genomic analysis suggested that strain XHP0099T harbored gene clusters for formaldehyde and the XoxF-type methanol oxidation and type 1 Calvin cycle, which could confer the methylotrophy pathway. Based on the phenotypic, phylogenetic, biochemical and chemotaxonomic analysis, strain XHP0099T represents a novel species of the genus Paracoccus, for which the name Paracoccus marinaquae sp. nov. is proposed. The type strain is XHP0099T (= JCM 34661 T = GDMCC 1.2414 T = MCCC 1K05846T).


Assuntos
Paracoccus , Fosfolipídeos , Fosfolipídeos/análise , Filogenia , Ubiquinona/química , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , Ácidos Graxos/análise , Água , Técnicas de Tipagem Bacteriana , Análise de Sequência de DNA
8.
Int J Syst Evol Microbiol ; 73(11)2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37916703

RESUMO

A Gram-stain-negative, yellow-pigmented, non-motile, rod-shaped, catalase-positive, strictly aerobic marine bacterium, designated XHP0103T, was isolated from seawater collected from the southern Yellow Sea, PR China (34° 45' 53″ N 119° 25' 30″ E). Strain XHP0103T grew optimally at 28 °C, pH 7.5 and in 1.0-3.0 % (w/v) sea salt. MK-6 was the major respiratory quinone. The major cellular fatty acids (>10%) were iso-C15 : 0, iso-C15 : 1 G and iso-C17 : 0 3-OH. The polar lipid profile contained phosphatidylethanolamine, an unidentified aminolipid, an unidentified glycolipid and an unidentified lipid. Results of 16S rRNA gene sequence analysis indicated that strain XHP0103T displayed highest sequence similarity to Aestuariibaculum marinum IP7T (94.1 %). However, the phylogenetic trees based on 16S rRNA gene sequences suggested that strain XHP0103T clustered with Tamlana crocina HST1-43T (93.4 % sequence similarity) and Aestuariivivens insulae AH-MY3T (93.5 %). Genome sequencing revealed that strain XHP0103T comprised 3 134 388 bp with 2770 protein-coding genes, and the DNA G+C content was 35.5 %. The average nucleotide identity and digital DNA-DNA hybridization values between strain XHP0103T and T. crocina HST1-43T were 73.6 and 17.3 %, respectively. Based on phylogenetic, phenotypic, genomic and chemotaxonomic evidence, strain XHP0103T represents a novel genus in the family Flavobacteriaceae, for which the name Marixanthotalea marina gen. nov., sp. nov. is proposed. The type strain is XHP0103T (=MCCC 1K06060T=JCM 34682T).


Assuntos
Ácidos Graxos , Flavobacteriaceae , Ácidos Graxos/química , Filogenia , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , Análise de Sequência de DNA , Composição de Bases , Técnicas de Tipagem Bacteriana , Água do Mar/microbiologia
9.
Inorg Chem ; 62(1): 583-590, 2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36563110

RESUMO

Ruthenium (Ru)-based materials, as a class of efficient hydrogen evolution reaction (HER) catalysts, play an important role in hydrogen generation by electrolysis of water in an alkaline solution for clean hydrogen energy. Hybrid nanostructure (HN) materials, which include two or more components with distinct functionality, show better performance than their individual materials, since HN materials can potentially integrate their advantages and overcome the weaknesses. However, it remains a challenge to construct Ru-based HN materials with desired crystal phases for enhanced HER performances. Herein, a series of new Ru-based HN materials (t-Ru-RuS2, S-Ru-RuS2, and T-Ru-RuS2) through phase engineering of nanomaterials (PEN) and chemical transformation are designed to achieve highly efficient HER properties. Owing to the plentiful formation of heterojunctions and amorphous/crystalline interfaces, the t-Ru-RuS2 HN delivers the most outstanding overpotential of 16 mV and owns a small Tafel slope of 29 mV dec-1 at a current density of 10 mA cm-2, which exceeds commercial Pt/C catalysts (34 mV, 38 mV dec-1). This work shows a new insight for HN and provides alternative opportunities in designing advanced electrocatalysts with low cost for HER in the hydrogen economy.

10.
Angew Chem Int Ed Engl ; 62(7): e202217456, 2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36511854

RESUMO

Lanthanide metal-organic frameworks (Ln-MOFs) are promising for luminescence detection of volatile organic compound (VOC) vapors, but usually suffer from the silent or quenched Ln3+ emission. Herein, we report a new dual-emissive Eu-MOF composed of the coordinatively unsaturated Eu9 clusters that afford abundant open metal sites to form a confined "binding pocket" to facilitate the preconcentration and recognition of VOCs. Single-crystal structural analyses reveal that specific analytes can replace the OH oscillators in the first coordination sphere of Eu3+ and form a unique hydrogen-bonding second-sphere adduct tying adjacent Eu9 clusters together to minimize their nonradiative vibrational decay. With the promoted Eu3+ luminescence, the MOF realizes real-time in situ visual sensing of THF vapor (<1 s) and shows a quantitative ratiometric response to the vapor pressure with a limit of detection down to 17.33 Pa. Also, it represents a top-performing ratiometric luminescent thermometer.

11.
J Med Virol ; 94(12): 5640-5652, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35971954

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection can cause coronavirus disease 2019 (COVID-19), an acute respiratory inflammation that has emerged worldwide since December 2019, and it quickly became a global epidemic. Inflammatory bowel disease (IBD) is a group of chronic nonspecific intestinal inflammatory diseases whose etiology has not been elucidated. The two have many overlapping symptoms in clinical presentation, such as abdominal pain, diarrhea, pneumonia, etc. Imbalance of the autoimmune system in IBD patients and long-term use of immunosuppressive drugs may increase the risk of infection; and systemic symptoms caused by COVID-19 may also induce or exacerbate intestinal inflammation. It has been found that the SARS-CoV-2 receptor angiotensin converting enzyme 2, which is highly expressed in the lung and intestine, is an inflammatory protective factor, and is downregulated and upregulated in COVID-19 and IBD, respectively, suggesting that there may be a coregulatory pathway. In addition, the immune activation pattern of COVID-19 and the cytokine storm in the inflammatory response have similar roles in IBD, indicating that the two diseases may influence each other. Therefore, this review aimed to address the following research questions: whether SARS-CoV-2 infection leads to the progression of IBD; whether IBD increases the risk of COVID-19 infection and poor prognosis; possible common mechanisms and genetic cross-linking between the two diseases; new treatment and care strategies for IBD patients, and the feasibility and risk of vaccination in the context of the COVID-19 epidemic.


Assuntos
COVID-19 , Doenças Inflamatórias Intestinais , Enzima de Conversão de Angiotensina 2 , COVID-19/complicações , Síndrome da Liberação de Citocina , Humanos , Doenças Inflamatórias Intestinais/complicações , Peptidil Dipeptidase A/genética , SARS-CoV-2
12.
Microb Pathog ; 164: 105448, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35189277

RESUMO

Endotoxin tolerance refers to a state refractory to subsequent lipopolysaccharide (LPS) stimulations following a primary LPS exposure. To study the relationship between endotoxin tolerance and macrophage polarization, endotoxin tolerance was induced by 1 µg/mL LPS from the periodontal pathogen, Porphyromonas gingivalis (P. gingivalis), in peritoneal macrophages (PMs) and bone marrow-derived macrophages (BMDMs). Repeated P. gingivalis LPS challenges increased the quantities of CD206+ PMs, while the number of CD86+CD206+ PMs was reduced compared with the non-tolerant group (p < 0.05). However, there were no changes in BMDMs (p > 0.05). Down regulations of TNF-α, IL-12, nitric oxide and MMP-2 production, and upregulated IL-10, MMP-9 levels and arginase-1 activities occurred in tolerant PMs and BMDMs (p < 0.05). P. gingivalis LPS-tolerant PMs and BMDMs also enhanced scrape-wound healing abilities of 15p-1 cells (p < 0.05). Expressions of phospho-signal transducer and activator of transcription 6 (p-STAT6) and protein tyrosine phosphatase 1B (PTP1B) were increased, while p-MEK1/2 levels were downregulated in tolerant PMs and BMDMs (p < 0.05). IL-10 production in tolerant Stat6 knockdown RAW264.7 cells was lower than tolerant control cells (p < 0.05). P. gingivalis LPS-tolerant macrophages represented an intermediate state between M1/M2 polarization, which functioned as M2-like cells, and led to limited inflammatory responses and enhanced wound healing activities. The PTP1B-MEK1/2-STAT6 signaling pathway might be involved in the polarization of tolerant macrophages.


Assuntos
Lipopolissacarídeos , Porphyromonas gingivalis , Tolerância à Endotoxina , Lipopolissacarídeos/metabolismo , Ativação de Macrófagos , Macrófagos/metabolismo
13.
J Org Chem ; 87(15): 9488-9496, 2022 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-35881945

RESUMO

A new one-pot preparation of 4-tetrazolyl-3,4-dihydroquinazolines has been reported. The Ugi-azide reactions of 2-azidobenzaldehydes, amines, trimethylsilyl azide, and isocyanides produced azide intermediates without separation, which were treated with isocyanides to give 4-tetrazolyl-3,4-dihydroquinazoline derivatives through a sequential Palladium-catalyzed azide-isocyanide cross-coupling/cyclization reaction in moderate to good yields. The biological evaluation demonstrated that compound 6c inhibited breast cancer cells well and displayed broad applications for synthesis and medicinal chemistry.


Assuntos
Cianetos , Paládio , Azidas , Catálise , Cianetos/química , Ciclização , Estrutura Molecular , Paládio/química
14.
Inorg Chem ; 61(15): 5800-5812, 2022 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-35385648

RESUMO

The hierarchical porous metal-organic framework (HP-MOF) has emerged as a hot topic in porous materials in consideration of their advantages in storage capacity and catalysis performance. Herein, we report the construction and property investigation of a series of HP-MOFs. A series of isoreticular microporous MOFs featuring the pacs topology network based on 2,4,6-tris(4-pyridyl)-1,3,5-triazine and different carboxylic acid ligands are found to be potential precursors to construct HP-MOFs. Through the decarboxylation of carboxylate ligands at high temperatures, a hierarchical porous structure could be obtained with the reservation of a crystalline framework. The formation of hierarchical pores is highly dependent on the structural and component nature (carboxylate ligands and metal centers) of the pristine MOF and the pyrolysis conditions (temperature and treatment time), indicating the highly tunable hierarchical pore characteristic of the HP-MOFs. By taking advantage of the increased pore volume and more exposed activation sites, the HP-MOFs reveal enhanced anionic dye adsorption capacity (800 mg·g-1 for Congo red and 140 mg·g-1 for methyl blue) and catalytic activity toward electrocatalytic oxygen reduction reaction (overpotential of 0.302 V at a current density of 10 mA·cm-2, 51 mV lower than that of the pristine MOF).

15.
J Nanobiotechnology ; 20(1): 170, 2022 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-35361219

RESUMO

Contrast-enhanced MR angiography (MRA) is a critical technique for vascular imaging. Nevertheless, the efficacy of MRA is often limited by the low rate of relaxation, short blood-circulation time, and metal ion-released potential long-term toxicity of clinical available Gd-based contrast agents. In this work, we report a facile and efficient strategy to achieve Gd-chelated organic nanoparticles with high relaxivity for T1-weighted MRA imaging. The Gd-chelated PEG-TCPP nanoparticles (GPT NPs) have been engineered composite structured consisting of Gd-chelated TCPP and PEG. The spherical structure of TCPP offers more chemical sites for Gd3+ coordination to improve the relaxivity and avoid leakage of the Gd3+ ions. The synthesized GPT NPs exhibit a high relaxation rate of 35.76 mM- 1 s- 1 at 3.0 T, which is higher than the rates for most reported MR contrast agents. Therefore, GPT NPs can be used for MRA with much stronger vascular signals, longer circulation time, and high-resolution arterial vascular visualization than those using clinical MR contrast agents at the same dose. This work may make the T1 MRI contrast agents for high-resolution angiography possible and offer a new candidate for preclinical and clinical applications of MR vascular imaging and vascular disease diagnosis.


Assuntos
Angiografia por Ressonância Magnética , Nanopartículas , Gadolínio/química , Angiografia por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/métodos , Metais , Nanopartículas/química
16.
Sheng Li Xue Bao ; 74(3): 489-494, 2022 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-35770646

RESUMO

High level noise can damage cochlear hair cells, auditory nerve and synaptic connections between cochlear hair cells and auditory nerve, resulting in noise-induced hearing loss (NIHL). Recent studies have shown that animal cochleae have circadian rhythm, which makes them different in sensitivity to noise throughout the day. Cochlear circadian rhythm has a certain relationship with brain-derived neurotrophic factor and glucocorticoids, which affects the degree of hearing loss after exposure to noise. In this review, we summarize the research progress of the regulation of cochlear sensitivity to noise by circadian rhythm and prospect the future research direction.


Assuntos
Ritmo Circadiano , Perda Auditiva Provocada por Ruído , Animais , Limiar Auditivo , Cóclea , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Células Ciliadas Auditivas , Ruído/efeitos adversos
17.
Entropy (Basel) ; 24(7)2022 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-35885233

RESUMO

Semantic-rich speech emotion recognition has a high degree of popularity in a range of areas. Speech emotion recognition aims to recognize human emotional states from utterances containing both acoustic and linguistic information. Since both textual and audio patterns play essential roles in speech emotion recognition (SER) tasks, various works have proposed novel modality fusing methods to exploit text and audio signals effectively. However, most of the high performance of existing models is dependent on a great number of learnable parameters, and they can only work well on data with fixed length. Therefore, minimizing computational overhead and improving generalization to unseen data with various lengths while maintaining a certain level of recognition accuracy is an urgent application problem. In this paper, we propose LGCCT, a light gated and crossed complementation transformer for multimodal speech emotion recognition. First, our model is capable of fusing modality information efficiently. Specifically, the acoustic features are extracted by CNN-BiLSTM while the textual features are extracted by BiLSTM. The modality-fused representation is then generated by the cross-attention module. We apply the gate-control mechanism to achieve the balanced integration of the original modality representation and the modality-fused representation. Second, the degree of attention focus can be considered, as the uncertainty and the entropy of the same token should converge to the same value independent of the length. To improve the generalization of the model to various testing-sequence lengths, we adopt the length-scaled dot product to calculate the attention score, which can be interpreted from a theoretical view of entropy. The operation of the length-scaled dot product is cheap but effective. Experiments are conducted on the benchmark dataset CMU-MOSEI. Compared to the baseline models, our model achieves an 81.0% F1 score with only 0.432 M parameters, showing an improvement in the balance between performance and the number of parameters. Moreover, the ablation study signifies the effectiveness of our model and its scalability to various input-sequence lengths, wherein the relative improvement is almost 20% of the baseline without a length-scaled dot product.

18.
Zhongguo Dang Dai Er Ke Za Zhi ; 24(5): 492-499, 2022 May 15.
Artigo em Chinês | MEDLINE | ID: mdl-35644188

RESUMO

OBJECTIVES: To study the influence of umbilical cord milking versus delayed cord clamping on the early prognosis of preterm infants with a gestational age of <34 weeks. METHODS: PubMed, Web of Science, Embase, the Cochrane Library, CINAHL, China National Knowledge Infrastructure, Wanfang Data, Weipu Database, and SinoMed were searched for randomized controlled trials on umbilical cord milking versus delayed cord clamping in preterm infants with a gestational age of <34 weeks published up to November 2021. According to the inclusion and exclusion criteria, two researchers independently performed literature screening, quality evaluation, and data extraction. Review Manger 5.4 was used for Meta analysis. RESULTS: A total of 11 articles were included in the analysis, with 1 621 preterm infants in total, among whom there were 809 infants in the umbilical cord milking group and 812 in the delayed cord clamping group. The Meta analysis showed that compared with delayed cord clamping, umbilical cord milking increased the mean blood pressure after birth (weighted mean difference=3.61, 95%CI: 0.73-6.50, P=0.01), but it also increased the incidence rate of severe intraventricular hemorrhage (RR=1.83, 95%CI: 1.08-3.09, P=0.02). There were no significant differences between the two groups in hemoglobin, hematocrit, blood transfusion rate, proportion of infants undergoing phototherapy, bilirubin peak, and incidence rates of complications such as periventricular leukomalacia and necrotizing enterocolitis (P>0.05). CONCLUSIONS: Compared with delayed cord clamping, umbilical cord milking may increase the risk of severe intraventricular hemorrhage in preterm infants with a gestational age of <34 weeks; however, more high-quality large-sample randomized controlled trials are needed for further confirmation.


Assuntos
Recém-Nascido Prematuro , Clampeamento do Cordão Umbilical , Hemorragia Cerebral , Constrição , Feminino , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Gravidez , Prognóstico , Cordão Umbilical/fisiologia
19.
Artigo em Inglês | MEDLINE | ID: mdl-31383670

RESUMO

Carbapenem-resistant Enterobacteriaceae (CRE) can be mechanistically classified into carbapenemase-producing Enterobacteriaceae (CPE) and non-carbapenemase-producing carbapenem nonsusceptible Enterobacteriaceae (NCPCRE). We sought to investigate the effect of antecedent carbapenem exposure as a risk factor for NCPCRE versus CPE. Among all patients with CRE colonization and infection, we conducted a case-control study comparing patients with NCPCRE (cases) and patients with CPE (controls). The presence of carbapenemases was investigated with phenotypic tests followed by PCR for predominant carbapenemase genes. We included 843 unique patients with first-episode CRE, including 387 (45.9%) NCPCRE and 456 (54.1%) CPE. The resistance genes detected in CPEs were blaNDM (42.8%), blaKPC (38.4%), and blaOXA-48-like (12.1%). After adjusting for confounders and clustering at the institutional level, the odds of prior 30-day carbapenem exposure was three times higher among NCPCRE than CPE patients (adjusted odds ratio [aOR], 3.48; 95% confidence interval [CI], 2.39 to 5.09; P < 0.001). The odds of prior carbapenem exposure and NCPCRE detection persisted in stratified analyses by Enterobacteriaceae species (Klebsiella pneumoniae and Escherichia coli) and carbapenemase gene (blaNDM and blaKPC). CPE was associated with male gender (aOR, 1.45; 95% CI, 1.07 to 1.97; P = 0.02), intensive care unit stay (aOR, 1.84; 95% CI, 1.24 to 2.74; P = 0.003), and hospitalization in the preceding 1 year (aOR, 1.42; 95% CI, 1.01 to 2.02; P = 0.05). In a large nationwide study, antecedent carbapenem exposure was a significant risk factor for NCPCRE versus CPE, suggesting a differential effect of antibiotic selection pressure.


Assuntos
Antibacterianos/efeitos adversos , Proteínas de Bactérias/metabolismo , Carbapenêmicos/efeitos adversos , Enterobacteriaceae/efeitos dos fármacos , beta-Lactamases/metabolismo , Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos , Enterobacteriáceas Resistentes a Carbapenêmicos/metabolismo , Estudos de Casos e Controles , Enterobacteriaceae/metabolismo , Infecções por Enterobacteriaceae/tratamento farmacológico , Escherichia coli/efeitos dos fármacos , Feminino , Humanos , Klebsiella pneumoniae/efeitos dos fármacos , Masculino , Testes de Sensibilidade Microbiana/métodos , Fatores de Risco
20.
Molecules ; 24(10)2019 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-31100775

RESUMO

We present two as-synthesized Fe(II)-based molecular catalysts with 1,10-phenanthroline (phen) ligands; Fe(phen)3Cl2 (1) and [Fe(phen)2(CH3CH2OH)Cl]Cl (2), and their robust catalytic properties for the conversion of CO2 to CO in DMF/TEOA (DMF = N,N'-dimethylformamide; TEOA = triethanolamine) solution containing Ru(bpy)32+ and BIH (1,3-dimethyl-2-phenyl-2,3- dihydro-1H-benzo-[d]-imidazole). High turnover numbers (TONs) of 19,376 were achieved with turnover frequencies (TOFs) of 3.07 s-1 for complex 1 (1.5 × 10-7 M). A quantum efficiency of 0.38% was observed after 5 h irradiated by 450 nm monochromatic light. The generation rate of CO2 and H2 were tuned by optimizing the experimental conditions, resulting in a high CO selectivity of 90%. The remarkable contribution of the photosensitizer to the total TONCO was found being 19.2% (as shown by tests under similar conditions without catalysts) when BIH was employed as a sacrificial electron donor. The product selectivity in complex 2 reached 95%, and the corresponding TONCO and TOFCO were 33,167 and 4.61 s-1 in the same concentration with complex 1 used as catalyst; respectively. This work provides guidance for future designs of simple, highly efficient and selective molecular catalytic systems that facilitate carbon-neutral solar-to-fuel conversion processes.


Assuntos
Dióxido de Carbono/metabolismo , Monóxido de Carbono/metabolismo , Ferro/metabolismo , Luz , Catálise/efeitos da radiação , Hidrogênio/metabolismo , Marcação por Isótopo , Redes e Vias Metabólicas , Processos Fotoquímicos , Fatores de Tempo
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