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1.
PhytoKeys ; 239: 267-273, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38577245

RESUMO

Oxalisxishuiensis, a new species of Oxalidaceae from Danxia landforms of Xishui County, Guizhou, China, is described and illustrated. It is morphologically similar to O.wulingensis by the two lateral leaflets arranged at about 180° angle and oblong pink petals with lilac veins, but clearly differs from the latter by leaflets almost as long as wide, obliquely obcordate lateral leaflets, shorter peduncles, longer capsule (1.2-1.5 cm vs. 0.5-0.7 cm) and alveolate seeds.

2.
Adv Mater ; : e2400737, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38572792

RESUMO

Electrode crosstalk between anode and cathode at elevated temperatures is identified as a real culprit triggering the thermal runaway of lithium-ion batteries. Herein, to address this challenge, a novel smart polymer electrolyte is prepared through in situ polymerization of methyl methacrylate and acrylic anhydride monomers within a succinonitrile-based dual-anion deep eutectic solvent. Owing to the abundant active unsaturated double bonds on the as-obtained polymer matrix end, this smart polymer electrolyte can spontaneously form a dense crosslinked polymer network under elevated temperatures, effectively slowing down the crosstalk diffusion kinetics of lithium ions and active gases. Impressively, LiCoO2/graphite pouch cells employing this smart polymer electrolyte demonstrate no thermal runaway even at the temperature up to 250 °C via accelerating rate calorimeter testing. Meanwhile, because of its abundance of functional motifs, this smart polymer electrolyte can facilitate the formation of stable and thermally robust electrode/electrolyte interface on both electrodes, ensuring the long cycle life and high safety of LIBs. In specific, this smart polymer electrolyte endows 1.1 Ah LiCoO2/graphite pouch cell with a capacity retention of 96% after 398 cycles at 0.2 C.

3.
Eur Rev Aging Phys Act ; 21(1): 4, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38383309

RESUMO

BACKGROUND: Respiratory muscle training is a continuous and standardized training of respiratory muscles, but the evidence of the effects on early stroke patients is not clear. This meta-analysis aimed to investigate the effects of respiratory muscle training on respiratory function and functional capacity in patients with early stroke. METHODS: PubMed, Embase, PEDro, ScienceDirect, AMED, CINAHL, and China National Knowledge Infrastructure databases were searched from inception to December 8, 2023 for articles about studies that 1) stroke patients with age ≥ 18 years old. Early stroke < 3 months at the time of diagnosis, 2) respiratory muscle training, including inspiratory and expiratory muscle training, 3) the following measurements are the outcomes: respiratory muscle strength, respiratory muscle endurance, pulmonary function testing, dyspnea fatigue score, and functional capacity, 4) randomized controlled trials. Studies that met the inclusion criteria were extracted data and appraised the methodological quality and risk of bias using the Physiotherapy Evidence Database scale and the Cochrane Risk of Bias tool by two independent reviewers. RevMan 5.4 with a random effect model was used for data synthesis and analysis. Mean differences (MD) or standard mean differences (SMD), and 95% confidence interval were calculated (95%CI). RESULTS: Nine studies met inclusion criteria, recruiting 526 participants (mean age 61.6 years). Respiratory muscle training produced a statistically significant effect on improving maximal inspiratory pressure (MD = 10.93, 95%CI: 8.51-13.36), maximal expiratory pressure (MD = 9.01, 95%CI: 5.34-12.69), forced vital capacity (MD = 0.82, 95%CI: 0.54-1.10), peak expiratory flow (MD = 1.28, 95%CI: 0.94-1.63), forced expiratory volume in 1 s (MD = 1.36, 95%CI: 1.13-1.59), functional capacity (SMD = 0.51, 95%CI: 0.05-0.98) in patients with early stroke. Subgroup analysis showed that inspiratory muscle training combined with expiratory muscle training was beneficial to the recovery of maximal inspiratory pressure (MD = 9.78, 95%CI: 5.96-13.60), maximal expiratory pressure (MD = 11.62, 95%CI: 3.80-19.43), forced vital capacity (MD = 0.87, 95%CI: 0.47-1.27), peak expiratory flow (MD = 1.51, 95%CI: 1.22-1.80), forced expiratory volume in 1 s (MD = 0.76, 95%CI: 0.41-1.11), functional capacity (SMD = 0.61, 95%CI: 0.08-1.13), while inspiratory muscle training could improve maximal inspiratory pressure (MD = 11.60, 95%CI: 8.15-15.05), maximal expiratory pressure (MD = 7.06, 95%CI: 3.50-10.62), forced vital capacity (MD = 0.71, 95%CI: 0.21-1.21), peak expiratory flow (MD = 0.84, 95%CI: 0.37-1.31), forced expiratory volume in 1 s (MD = 0.40, 95%CI: 0.08-0.72). CONCLUSIONS: This study provides good-quality evidence that respiratory muscle training is effective in improving respiratory muscle strength, pulmonary function, and functional capacity for patients with early stroke. Inspiratory muscle training combined with expiratory muscle training seems to promote functional recovery in patients with early stroke more than inspiratory muscle training alone. TRIAL REGISTRATION: Prospero registration number: CRD42021291918.

4.
Angew Chem Int Ed Engl ; 63(5): e202315710, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38078788

RESUMO

High energy density lithium-ion batteries (LIBs) adopting high-nickel layered oxide cathodes and silicon-based composite anodes always suffer from unsatisfied cycle life and poor safety performance, especially at elevated temperatures. Electrode /electrolyte interphase regulation by functional additives is one of the most economic and efficacious strategies to overcome this shortcoming. Herein, cyano-groups (-CN) are introduced into lithium fluorinated phosphate to synthesize a novel multifunctional additive of lithium tetrafluoro (1,2-dihydroxyethane-1,1,2,2-tetracarbonitrile) phosphate (LiTFTCP), which endows high nickel LiNi0.8 Co0.1 Mn0.1 O2 /SiOx -graphite composite full cell with an ultrahigh cycle life and superior safety characteristics, by adding only 0.5 wt % LiTFTCP into a LiPF6 -carbonate baseline electrolyte. It is revealed that LiTFTCP additive effectively suppresses the HF generation and facilitates the formation of a robust and heat-resistant cyano-enriched CEI layer as well as a stable LiF-enriched SEI layer. The favorable SEI/CEI layers greatly lessen the electrode degradation, electrolyte consumption, thermal-induced gassing and total heat-releasing. This work illuminates the importance of additive molecular engineering and interphase regulation in simultaneously promoting the cycling and thermal safety of LIBs with high-nickel NCMxyz cathode and silicon-based composite anode.

5.
Adv Sci (Weinh) ; 11(7): e2305753, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38044323

RESUMO

High nickel (Ni ≥ 80%) lithium-ion batteries (LIBs) with high specific energy are one of the most important technical routes to resolve the growing endurance anxieties. However, because of their extremely aggressive chemistries, high-Ni (Ni ≥ 80%) LIBs suffer from poor cycle life and safety performance, which hinder their large-scale commercial applications. Among varied strategies, electrolyte engineering is very powerful to simultaneously enhance the cycle life and safety of high-Ni (Ni ≥ 80%) LIBs. In this review, the pivotal challenges faced by high-Ni oxide cathodes and conventional LiPF6 -carbonate-based electrolytes are comprehensively summarized. Then, the functional additives design guidelines for LiPF6 -carbonate -based electrolytes and the design principles of high voltage resistance/high safety novel electrolytes are systematically elaborated to resolve these pivotal challenges. Moreover, the proposed thermal runaway mechanisms of high-Ni (Ni ≥ 80%) LIBs are also reviewed to provide useful perspectives for the design of high-safety electrolytes. Finally, the potential research directions of electrolyte engineering toward high-performance high-Ni (Ni ≥ 80%) LIBs are provided. This review will have an important impact on electrolyte innovation as well as the commercial evolution of high-Ni (Ni ≥ 80%) LIBs, and also will be significant to breakthrough the energy density ceiling of LIBs.

6.
Fitoterapia ; 172: 105770, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38056699

RESUMO

Thirteen diterpenoids (1-13), classified into four structurally diverse carbon skeletons, including 1,5-seco-kalmane (1 and 6), grayanane (2-11), kalmane (12), and rhodomollane (13), were isolated from the flowers extract of Rhododendron molle. Among them, rhodomollinols A - E (1-5) were five new diterpenoids and their structures were elucidated by extensive spectroscopic methods including HRESIMS, UV, IR, 1D and 2D NMR, as well as quantum ECD calculations. Rhodomollinol A (1) is the first representative of a 6-deoxy-1,5-seco-kalmane diterpenoid. The abnormal NMR phenomenon of the presence of only 9 carbon resonances instead of 20 carbons in the 13C NMR spectrum of 1 was observed and elucidated by the quantum NMR calculations. All diterpenoids 1-13 showed significant analgesic activities in an acetic acid-induced writhing model. It's the first time to report the analgesic activity of a rhodomollane-type diterpenoid. At a dose of 1.0 mg/kg, diterpenoids 1-3, 6, 8, 9, and 12 reduced the writhe numbers with inhibition rates over 50%, and 9 exhibited stronger analgesic activity with a writhe inhibition rate of 89.7% than that of the positive control morphine. Importantly, even at the lowest dose of 0.04 mg/kg, rhodomollinols A (1) and B (2), rhodomollein X (7), and 2-O-methylrhodojaponin VI (9) still showed more potent analgesic effects than morphine with the writhe inhibition rates of 51.8%, 48.0%, 61.7%, and 60.0%, respectively. A preliminary structure-activity relationship might provide some clues to design potential analgesics on the basis of structurally diverse Ericaceae diterpenoids.


Assuntos
Diterpenos , Rhododendron , Rhododendron/química , Estrutura Molecular , Flores/química , Analgésicos/farmacologia , Diterpenos/farmacologia , Diterpenos/química , Carbono/análise , Derivados da Morfina/análise
7.
Bioorg Chem ; 142: 106928, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37922768

RESUMO

A systematical investigation on the chemical constituents of the flowers of Rhododendron molle (Ericaceae) led to the isolation and characterization of thirty-eight highly functionalized grayanane diterpenoids (1-38), including twelve novel analogues molleblossomins A-L (1-12). Their structures were elucidated by comprehensive methods, including 1D and 2D NMR analysis, calculated ECD, 13C NMR calculations with DP4+ probability analysis, and single crystal X-ray diffraction. Molleblossomins A (1), B (2), and E (5) are the first representatives of 2ß,3ß:9ß,10ß-diepoxygrayanane, 2,3-epoxygrayan-9(11)-ene, and 5,9-epoxygrayan-1(10),2(3)-diene diterpenoids, respectively. Molleblossomins G (7) and H (8) represent the first examples of 1,3-dioxolane-grayanane conjugates furnished with the acetaldehyde and 4-hydroxylbenzylidene acetal moieties, respectively. All grayanane diterpenoids 1-38 were screened for their analgesic activities in the acetic acid-induced writhing model, and all of them exhibited significant analgesic activities. Diterpenoids 6, 13, 14, 17, 20, and 25 showed more potent analgesic effects than morphine at a lower dose of 0.2 mg/kg, with the inhibition rates of 51.4%, 68.2%, 94.1%, 66.9%, 97.7%, and 60.0%, respectively. More importantly, even at the lowest dose of 0.04 mg/kg, rhodomollein X (14), rhodojaponin VI (20), and rhodojaponin VII (22) still significantly reduced the number of writhes in the acetic acid-induced pain model with the percentages of 61.7%, 85.8%, and 64.6%, respectively. The structure-activity relationship was summarized and might provide some hints to design novel analgesics based on the functionalized grayanane diterpenoids.


Assuntos
Diterpenos , Rhododendron , Rhododendron/química , Estrutura Molecular , Flores/química , Analgésicos/farmacologia , Analgésicos/uso terapêutico , Analgésicos/química , Diterpenos/farmacologia , Diterpenos/uso terapêutico , Diterpenos/química , Ácido Acético/análise
8.
Plant Signal Behav ; 18(1): 2293405, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-38104263

RESUMO

Similar to other orchid species, Paphiopedilum hirsutissimum (Lindl.ex Hook.) Stein, relies on nutrients provided by mycorrhizal fungus for seed germination and seedling development in the wild owing to a lack of endosperm in its seeds. Therefore, obtaining suitable and specialized fungi to enhance seed germination, seedling formation, and further development is considered a powerful tool for orchid seedling propagation, reintroduction, and species conservation. In this study, we investigated the diversity, abundance, and frequency of endophytic fungal strains in the root organs of P. hirsutissimum. One family and five genera of the fungi were isolated and identified through rDNA-ITS sequencing. The ability of isolated fungi to germinate in vitro from the seeds of this species was evaluated, and the development of P. hirsutissimum protocorm has been described. The findings showed that the treatments inoculated with endophytic fungal DYXY033 may successfully support the advanced developmental stage of seedlings up to stage 5. In addition, scanning electron microscopy (SEM) revealed that the mycelium of this strain began to invade from either end of the seeds up to the embryo, extending rapidly from the inside to the outside. Its lengthening resulted in the bursting of the seed coat to form protocorms, which developed into seedlings. The results showed that DYXY033 has a high degree of mycobiont specificity under in vitro symbiotic seed germination conditions and is a representative mycorrhizal fungus with ecological value for the species. In summary, this strain may particularly be significant for the protection of P. hirsutissimum species that are endangered in China. In the long run, it may also contribute to global efforts in reintroducing orchid species and in realizing in situ restorations of threatened orchid populations.


Assuntos
Micorrizas , Orchidaceae , Plântula , Germinação , Sementes , Simbiose , Orchidaceae/microbiologia , China
9.
iScience ; 26(8): 107476, 2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37599823

RESUMO

Mutations of the GABA-A receptor subunit ß1 (GABRB1) gene are found in autism patients. However, it remains unclear how mutations in Gabrb1 may lead to autism. We generated Gabrb1-/- mouse model, which showed autistic-like behaviors. We carried out RNA-seq on the hippocampus and found glutamatergic pathway may be involved. We further carried out single-cell RNA sequencing on the whole brain followed by qRT-PCR, immunofluorescence, electrophysiology, and metabolite detection on specific cell types. We identified the up-regulated Glul/Slc38a3 in astrocytes, Grin1/Grin2b in neurons, glutamate, and the ratio of Glu/GABA in the hippocampus. Consistent with these results, increased NMDAR-currents and reduced GABAAR-currents in the CA1 neurons were detected in Gabrb1-/- mice. NMDAR antagonist memantine or Glul inhibitor methionine sulfoximine could rescue the abnormal behaviors in Gabrb1-/- mice. Our data reveal that upregulation of the glutamatergic synapse pathway, including NMDARs at neuronal synapses and glutamine exported by astrocytes, may lead to autistic-like behaviors.

10.
Front Oncol ; 13: 1076997, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37152061

RESUMO

Background: Male breast cancer (MBC) is rare, which has restricted prospective research among MBC patients. With effective treatments, the prognosis of MBC patients has improved and developing a second primary malignancy (SPM) has become a life-threatening event for MBC survivors. However, few studies have focused on the prognosis of MBC patients and looked into the SPM issue in MBC survivors. Method: We reviewed MBC patients diagnosed between 1990 and 2016 from the latest Surveillance, Epidemiology, and End Results (SEER) Plus database. Competing risk models and nomograms were conducted for predicting the risk of cancer-specific death and SPM occurrence. C-indexes, calibration curves, ROC curves, and decision curve analysis (DCA) curves were applied for validation. Result: A total of 1,843 MBC patients with complete information were finally enrolled and 60 (3.26%) had developed an SPM. Prostate cancer (40%) was the most common SPM. The median OS of all the enrolled patients was 102.41 months, while the median latency from the initial MBC diagnosis to the subsequent diagnosis of SPM was 67.2 months. The patients who suffered from an SPM shared a longer OS than those patients with only one MBC (p = 0.027). The patients were randomly divided into the development cohort and the validation cohort (at a ratio of 7:3). The Fine and Gray competing risk model was used to identify the risk factors. Two nomograms were constructed and validated to predict the 5-year, 8-year, and 10-year survival probability of MBC patients, both of which had good performance in the C-index, ROC curves, calibration plots, and DCA curves, showing the ideal discrimination capability and predictive value clinically. Furthermore, we, for the first time, constructed a nomogram based on the competing risk model to predict the 5-year, 8-year, and 10-year probability of developing an SPM in MBC survivors, which also showed good discrimination, calibration, and clinical effectiveness. Conclusion: We, for the first time, included treatment information and clinical parameters to construct a nomogram to predict not only the survival probability of MBC patients but also the probability of developing an SPM in MBC survivors, which were helpful in individual risk estimation, patient follow-up, and counseling in MBC patients.

11.
Adv Mater ; 35(25): e2301312, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36999377

RESUMO

In lithium-metal batteries (LMBs), the compatibility of Li anode and conventional lithium hexafluorophosphate-(LiPF6 ) carbonate electrolyte is poor owing to the severe parasitic reactions. Herein, to resolve this issue, a delicately designed additive of potassium perfluoropinacolatoborate (KFPB) is unprecedentedly synthesized. On the one hand, KFPB additive can regulate the solvation structure of the carbonate electrolyte, promoting the formation of Li+ FPB- and K+ PF6 - ion pairs with lower lowest unoccupied molecular orbital (LUMO) energy levels. On the other hand, FPB- anion possesses strong adsorption ability on Li anode. Thus, anions can preferentially adsorb and decompose on the Li-anode surface to form a conductive and robust solid-electrolyte interphase (SEI) layer. Only with a trace amount of KFPB additive (0.03 m) in the carbonate electrolyte, Li dendrites' growth can be totally suppressed, and Li||Cu and Li||Li half cells exhibit excellent Li-plating/stripping stability upon cycling. Encouragingly, KFPB-assisted carbonate electrolyte enables high areal capacity LiCoO2 ||Li, LiNi0.8 Co0.1 Mn0.1 O2 (NCM811)||Li, and LiNi0.8 Co0.05 Al0.15 O2 (NCA)||Li LMBs with superior cycling stability, showing its excellent universality. This work reveals the importance of designing novel additives to regulate the solvation structure of carbonate electrolytes in improving its interface compatibility with the Li anode.

12.
Magn Reson Chem ; 61(6): 386-391, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36929032

RESUMO

Two new sesquiterpenoids, dendroaduoid A (1) and dendroaduol (2), together with four known sesquiterpenoids were isolated from the stems of Dendrobium aduncum. Their structures were identified by HR-ESI-MS and NMR experiments, and the complete assignments of 1 H and 13 C NMR data for two new sesquiterpenoids were obtained by the aid of HSQC, HMBC, 1 H-1 H COSY, NOESY, and ECD techniques. The cytotoxic effects of the isolated compounds on four tumor cell lines (HCT-116, HepG2, A549, and SW1990) were evaluated using MTT assay. Otherwise, the inhibitory activity of these six sesquiterpenoids on glycosidase was also evaluated.


Assuntos
Dendrobium , Sesquiterpenos , Linhagem Celular Tumoral , Sesquiterpenos/farmacologia
13.
J Am Chem Soc ; 145(5): 3196-3203, 2023 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-36696679

RESUMO

Extracellular protein disulfide isomerase (PDI) is a promising target for thrombotic-related diseases. Four potent PDI inhibitors with unprecedented chemical architectures, piericones A-D (1-4), were isolated from Pieris japonica. Their structures were elucidated by spectroscopic data analysis, chemical methods, quantum 13C nuclear magnetic resonance DP4+ and electronic circular dichroism calculations, and single-crystal X-ray diffraction analysis. Piericones A (1) and B (2) were nanomolar noncompetitive PDI inhibitors possessing an unprecedented 3,6,10,15-tetraoxatetracyclo[7.6.0.04,9.01,12]pentadecane motif with nine contiguous stereogenic centers. Their biosynthetic pathways were proposed to include a key intermolecular aldol reaction and an intramolecular 1,2-migration reaction. Piericone A (1) significantly inhibited in vitro platelet aggregation and fibrin formation and in vivo thrombus formation via the inhibition of extracellular PDI without increasing the bleeding risk. The molecular docking and dynamics simulation of 1 and 2 provided a novel structure basis to develop PDI inhibitors as potent antithrombotics.


Assuntos
Isomerases de Dissulfetos de Proteínas , Trombose , Humanos , Isomerases de Dissulfetos de Proteínas/química , Plaquetas/metabolismo , Fibrinolíticos/metabolismo , Simulação de Acoplamento Molecular , Trombose/metabolismo
14.
Int J Biol Macromol ; 225: 1437-1448, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36435468

RESUMO

To overcome the low energy density and poor conductivity of conventional electrode materials for building supercapacitor, herein, a hybrid hydrogel prepared from compositing bio-based chitosan with holey graphene oxide by microwave-assisted hydrothermal is proposed. This binary hydrogel is endowed with heteroatomic functional groups and conductive porous network by chemical pretreatments, where amides and carboxyl groups are introduced during the acylation modification of chitosan to enable it soluble in water for sufficient reaction, while the oxidation etching for graphene oxide in the defect area by H2O2 facilitates in-plane nanopores network to provide abundant active surface and short ion diffusion pathway. Benefited from the high conductivity and flexibility, this hydrogel present promising performance when used as additive-free electrode in a three-electrode, with a high specific capacitance of 377 F/g at 5 A/g. The rich nitrogen and oxygen groups on surface of the hydrogel contribute to high capacitance directly, while the in-plane nanopores and hierarchically porous network benefit to promote their wettability, accelerate the charge transfer and enhance their charge storage ability. When the hydrogel composite is adopted into a flexible solid-state supercapacitor employing lignin hydrogel electrolyte, it unfolds a specific capacitance of 210 F/g at 0.5 A/g, with an ultrahigh energy density of 31 Wh/kg at the power density of 150 W/kg. The solid-state supercapacitor exhibits promising potential in applications such as signal sensor and portable energy storage.


Assuntos
Quitosana , Hidrogéis , Peróxido de Hidrogênio , Porosidade , Eletrodos
15.
Br J Pharmacol ; 180(3): 287-307, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36166754

RESUMO

BACKGROUND AND PURPOSE: Thrombosis is a major cause of morbidity and mortality worldwide. Platelet activation by exposed collagen through glycoprotein VI (GPVI) and formation of neutrophil extracellular traps (NETs) are critical pathogenic factors for arterial and venous thrombosis. Both events are regulated by spleen tyrosine kinase (Syk)-mediated signalling events. Asebogenin is a dihydrochalcone whose pharmacological effects remain largely unknown. This study aims to investigate the antithrombotic effects of asebogenin and the underlying molecular mechanisms. EXPERIMENTAL APPROACH: Platelet aggregation was assessed using an aggregometer. Platelet P-selectin exposure, integrin activation and calcium mobilization were determined by flow cytometry. NETs formation was assessed by SYTOX Green staining and immunohistochemistry. Quantitative phosphoproteomics, microscale thermophoresis, in vitro kinase assay and molecular docking combined with dynamics simulation were performed to characterize the targets of asebogenin. The in vivo effects of asebogenin on arterial thrombosis were investigated using FeCl3 -induced and laser-induced injury models, whereas those of venous thrombosis were induced by stenosis of the inferior vena cava. KEY RESULTS: Asebogenin inhibited a series of GPVI-induced platelet responses and suppressed NETs formation induced by proinflammatory stimuli. Mechanistically, asebogenin directly interfered with the phosphorylation of Syk at Tyr525/526, which is important for its activation. Further, asebogenin suppressed arterial thrombosis demonstrated by decreased platelet accumulation and fibrin generation and attenuated venous thrombosis determined by reduced neutrophil accumulation and NETs formation, without increasing bleeding risk. CONCLUSION AND IMPLICATIONS: Asebogenin exhibits potent antithrombotic effects by targeting Syk and is a potential lead compound for the development of efficient and safe antithrombotic agents.


Assuntos
Fibrinolíticos , Trombose , Humanos , Fosforilação , Fibrinolíticos/farmacologia , Simulação de Acoplamento Molecular , Agregação Plaquetária , Ativação Plaquetária , Plaquetas , Trombose/tratamento farmacológico , Trombose/metabolismo , Quinase Syk/metabolismo , Glicoproteínas da Membrana de Plaquetas/metabolismo
16.
Artigo em Inglês | MEDLINE | ID: mdl-36306295

RESUMO

We propose self-adaptive training-a unified training algorithm that dynamically calibrates and enhances training processes by model predictions without incurring an extra computational cost-to advance both supervised and self-supervised learning of deep neural networks. We analyze the training dynamics of deep networks on training data that are corrupted by, e.g., random noise and adversarial examples. Our analysis shows that model predictions are able to magnify useful underlying information in data and this phenomenon occurs broadly even in the absence of any label information, highlighting that model predictions could substantially benefit the training processes: self-adaptive training improves the generalization of deep networks under noise and enhances the self-supervised representation learning. The analysis also sheds light on understanding deep learning, e.g., a potential explanation of the recently-discovered double-descent phenomenon in empirical risk minimization and the collapsing issue of the state-of-the-art self-supervised learning algorithms. Experiments on the CIFAR, STL, and ImageNet datasets verify the effectiveness of our approach in three applications: classification with label noise, selective classification, and linear evaluation. To facilitate future research, the code has been made publicly available at https://github.com/LayneH/self-adaptive-training.

17.
Biol Psychiatry ; 92(3): 179-192, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35489874

RESUMO

BACKGROUND: Depression is the most common mental illness. Mounting evidence suggests that dysregulation of extracellular ATP (adenosine triphosphate) is involved in the pathophysiology of depression. However, the cellular and neural circuit mechanisms through which ATP modulates depressive-like behavior remain elusive. METHODS: By use of ex vivo slice electrophysiology, chemogenetic manipulations, RNA interference, gene knockout, behavioral testing, and two depression mouse models, one induced by chronic social defeat stress and one caused by a IP3R2-null mutation, we systematically investigated the cellular and neural circuit mechanisms underlying ATP deficiency-induced depressive-like behavior. RESULTS: Deficiency of extracellular ATP in both defeated susceptible mice and IP3R2-null mutation mice led to reduced GABAergic (gamma-aminobutyric acidergic) inhibition and elevated excitability in lateral habenula-projecting, but not dorsal raphe-projecting, medial prefrontal cortex (mPFC) neurons. Furthermore, the P2X2 receptor in GABAergic interneurons mediated ATP modulation of lateral habenula-projecting mPFC neurons and depressive-like behavior. Remarkably, chemogenetic activation of the mPFC-lateral habenula pathway induced depressive-like behavior in C57BL/6J mice, while inhibition of this pathway was sufficient to alleviate the behavioral impairment in both defeated susceptible and IP3R2-null mutant mice. CONCLUSIONS: Overall, our study provides compelling evidence that ATP level in the mPFC is critically involved in regulating depressive-like behavior in a pathway-specific manner. These results shed new light on the mechanisms underlying depression and the antidepressant effect of ATP.


Assuntos
Habenula , Trifosfato de Adenosina/metabolismo , Animais , Depressão/etiologia , Núcleo Dorsal da Rafe/metabolismo , Habenula/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Córtex Pré-Frontal/metabolismo
18.
J Colloid Interface Sci ; 605: 790-802, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34371424

RESUMO

Carbon aerogels are prepared by a thermal treating-freeze drying approach from chitosan, with glycine hydrochloride ionic liquid (IL) acting as solvent and nitrogen source. Different post-treatments such as ball milling and high temperature carbonization are employed to functionalize the obtained carbon aerogels with tuned properties, making it promising candidates as fluorescence material (NACs-Q), electrode material (FDC-800) and catalyst support (NACPd-C). NACs-Q is water-soluble quantum dot with average particle sizes of 3.8 nm, presenting excitation-/emission-independent and pH-sensitive properties, which could be used as sensor for testing acetone vapor or an "on-off-on" sensor for detections of Fe3+ and vitamin C in fruits. FDC-800 exhibits fluffy lamellar structure with developed micro-mesopores and nitrogen-containing groups on their surfaces, which is beneficial for building flexible solid-state supercapacitor with excellent performance, delivering a capacitance of 208F/g at 0.5 A/g, and achieving an energy density of 7.2 W h/kg at a power density of 50 W/kg. Moreover, NACPd-C can be used as catalyst for phenol hydrogenation, and phenol conversion of 100% with cyclohexanone selectivity of 98.3% is achieved, due to the synergetic effects of the Pd active-site, the N-containing groups, and the Lewis acid sites on the support.


Assuntos
Carbono , Quitosana , Capacitância Elétrica , Nitrogênio , Porosidade
19.
Mol Psychiatry ; 27(2): 896-906, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34697452

RESUMO

Neuroplasticity in the medial prefrontal cortex (mPFC) is essential for fear extinction, the process of which forms the basis of the general therapeutic process used to treat human fear disorders. However, the underlying molecules and local circuit elements controlling neuronal activity and concomitant induction of plasticity remain unclear. Here we show that sustained plasticity of the parvalbumin (PV) neuronal network in the infralimbic (IL) mPFC is required for fear extinction in adult male mice and identify the involvement of neuregulin 1-ErbB4 signalling in PV network plasticity-mediated fear extinction. Moreover, regulation of fear extinction by basal medial amygdala (BMA)-projecting IL neurons is dependent on PV network configuration. Together, these results uncover the local molecular circuit mechanisms underlying mPFC-mediated top-down control of fear extinction, suggesting alterative therapeutic approaches to treat fear disorders.


Assuntos
Extinção Psicológica , Medo , Animais , Extinção Psicológica/fisiologia , Medo/fisiologia , Masculino , Camundongos , Neuregulina-1 , Plasticidade Neuronal/fisiologia , Parvalbuminas , Córtex Pré-Frontal/fisiologia , Receptor ErbB-4
20.
J Colloid Interface Sci ; 605: 82-90, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34311315

RESUMO

A highly stable Pd-loaded N-doped carbon catalyst (ACNpd) for phenol hydrogenation was prepared from chitosan by hydrothermal carbonization. ACNpd does not require a reduction step before catalytic use due to the Pd in the as-prepared catalyst mainly exists in the form of Pd0 (80%). The carbon support involves N-containing groups such as pyridinic nitrogen and pyrrolic nitrogen, which could provide basic sites to adsorb phenol effectively. The as-fabricated ACNpd shows high catalytic performance with turnover frequency (TOF) of 29.34 h-1. Accordingly, a phenol conversion of 100% and a cyclohexanone selectivity of 99.1% are achieved in 5 h at 100 °C and 1 MPa H2. This outstanding performance is attributed to the synergetic effects of the Pd particles, the N-functional groups, and the Lewis acid sites on the support. The carbon support presents intrinsic Lewis acid sites due to its electrophilicity, and Pd doping further increases the strength of such acid sites as it causes electron-deficient structural features. Moreover, the Lewis acid sites inhibit the over-hydrogenation from cyclohexanone to cyclohexanol. This study provides new insights into the application of functional biomass-based carbon materials as catalyst supports.


Assuntos
Carbono , Quitosana , Cicloexanonas , Hidrogenação , Fenol , Fenóis
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