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1.
Cell ; 183(2): 442-456.e16, 2020 10 15.
Article in English | MEDLINE | ID: mdl-32937107

ABSTRACT

Hantaviruses are rodent-borne viruses causing serious zoonotic outbreaks worldwide for which no treatment is available. Hantavirus particles are pleomorphic and display a characteristic square surface lattice. The envelope glycoproteins Gn and Gc form heterodimers that further assemble into tetrameric spikes, the lattice building blocks. The glycoproteins, which are the sole targets of neutralizing antibodies, drive virus entry via receptor-mediated endocytosis and endosomal membrane fusion. Here we describe the high-resolution X-ray structures of the heterodimer of Gc and the Gn head and of the homotetrameric Gn base. Docking them into an 11.4-Å-resolution cryoelectron tomography map of the hantavirus surface accounted for the complete extramembrane portion of the viral glycoprotein shell and allowed a detailed description of the surface organization of these pleomorphic virions. Our results, which further revealed a built-in mechanism controlling Gc membrane insertion for fusion, pave the way for immunogen design to protect against pathogenic hantaviruses.


Subject(s)
Membrane Glycoproteins/metabolism , Membrane Glycoproteins/ultrastructure , Orthohantavirus/chemistry , Glycoproteins/chemistry , Glycoproteins/ultrastructure , Orthohantavirus/metabolism , Membrane Glycoproteins/chemistry , Membrane Glycoproteins/physiology , Protein Conformation , RNA Viruses , Viral Envelope Proteins/chemistry , Viral Envelope Proteins/ultrastructure , Virion , Virus Internalization
2.
Cell ; 183(3): 730-738.e13, 2020 10 29.
Article in English | MEDLINE | ID: mdl-32979942

ABSTRACT

SARS-CoV-2 is an enveloped virus responsible for the COVID-19 pandemic. Despite recent advances in the structural elucidation of SARS-CoV-2 proteins, the detailed architecture of the intact virus remains to be unveiled. Here we report the molecular assembly of the authentic SARS-CoV-2 virus using cryoelectron tomography (cryo-ET) and subtomogram averaging (STA). Native structures of the S proteins in pre- and postfusion conformations were determined to average resolutions of 8.7-11 Å. Compositions of the N-linked glycans from the native spikes were analyzed by mass spectrometry, which revealed overall processing states of the native glycans highly similar to that of the recombinant glycoprotein glycans. The native conformation of the ribonucleoproteins (RNPs) and their higher-order assemblies were revealed. Overall, these characterizations revealed the architecture of the SARS-CoV-2 virus in exceptional detail and shed light on how the virus packs its ∼30-kb-long single-segmented RNA in the ∼80-nm-diameter lumen.


Subject(s)
Betacoronavirus/physiology , Betacoronavirus/ultrastructure , Virus Assembly , Animals , Chlorocebus aethiops , Cryoelectron Microscopy , Humans , Mass Spectrometry , Models, Molecular , Protein Conformation , SARS-CoV-2 , Vero Cells , Viral Proteins/chemistry , Viral Proteins/ultrastructure , Virus Cultivation
3.
Nature ; 616(7955): 56-60, 2023 04.
Article in English | MEDLINE | ID: mdl-36949191

ABSTRACT

Quantum error correction (QEC) aims to protect logical qubits from noises by using the redundancy of a large Hilbert space, which allows errors to be detected and corrected in real time1. In most QEC codes2-8, a logical qubit is encoded in some discrete variables, for example photon numbers, so that the encoded quantum information can be unambiguously extracted after processing. Over the past decade, repetitive QEC has been demonstrated with various discrete-variable-encoded scenarios9-17. However, extending the lifetimes of thus-encoded logical qubits beyond the best available physical qubit still remains elusive, which represents a break-even point for judging the practical usefulness of QEC. Here we demonstrate a QEC procedure in a circuit quantum electrodynamics architecture18, where the logical qubit is binomially encoded in photon-number states of a microwave cavity8, dispersively coupled to an auxiliary superconducting qubit. By applying a pulse featuring a tailored frequency comb to the auxiliary qubit, we can repetitively extract the error syndrome with high fidelity and perform error correction with feedback control accordingly, thereby exceeding the break-even point by about 16% lifetime enhancement. Our work illustrates the potential of hardware-efficient discrete-variable encodings for fault-tolerant quantum computation19.

4.
Proc Natl Acad Sci U S A ; 121(29): e2400883121, 2024 Jul 16.
Article in English | MEDLINE | ID: mdl-38980908

ABSTRACT

Gasdermin D (GSDMD)-mediated pyroptotic cell death drives inflammatory cytokine release and downstream immune responses upon inflammasome activation, which play important roles in host defense and inflammatory disorders. Upon activation by proteases, the GSDMD N-terminal domain (NTD) undergoes oligomerization and membrane translocation in the presence of lipids to assemble pores. Despite intensive studies, the molecular events underlying the transition of GSDMD from an autoinhibited soluble form to an oligomeric pore form inserted into the membrane remain incompletely understood. Previous work characterized S-palmitoylation for gasdermins from bacteria, fungi, invertebrates, as well as mammalian gasdermin E (GSDME). Here, we report that a conserved residue Cys191 in human GSDMD was S-palmitoylated, which promoted GSDMD-mediated pyroptosis and cytokine release. Mutation of Cys191 or treatment with palmitoyltransferase inhibitors cyano-myracrylamide (CMA) or 2-bromopalmitate (2BP) suppressed GSDMD palmitoylation, its localization to the membrane and dampened pyroptosis or IL-1ß secretion. Furthermore, Gsdmd-dependent inflammatory responses were alleviated by inhibition of palmitoylation in vivo. By contrast, coexpression of GSDMD with palmitoyltransferases enhanced pyroptotic cell death, while introduction of exogenous palmitoylation sequences fully restored pyroptotic activities to the C191A mutant, suggesting that palmitoylation-mediated membrane localization may be distinct from other molecular events such as GSDMD conformational change during pore assembly. Collectively, our study suggests that S-palmitoylation may be a shared regulatory mechanism for GSDMD and other gasdermins, which points to potential avenues for therapeutically targeting S-palmitoylation of gasdermins in inflammatory disorders.


Subject(s)
Cysteine , Intracellular Signaling Peptides and Proteins , Lipoylation , Phosphate-Binding Proteins , Pyroptosis , Phosphate-Binding Proteins/metabolism , Phosphate-Binding Proteins/genetics , Humans , Intracellular Signaling Peptides and Proteins/metabolism , Intracellular Signaling Peptides and Proteins/genetics , Cysteine/metabolism , Animals , Mice , Cytokines/metabolism , HEK293 Cells , Inflammasomes/metabolism , Gasdermins
5.
Trends Biochem Sci ; 47(2): 173-186, 2022 02.
Article in English | MEDLINE | ID: mdl-34511334

ABSTRACT

Viruses are macromolecular machineries that hijack cellular metabolism for replication. Enveloped viruses comprise a large variety of RNA and DNA viruses, many of which are notorious human or animal pathogens. Despite their importance, the presence of lipid bilayers in their assembly has made most enveloped viruses too pleomorphic to be reconstructed as a whole by traditional structural biology methods. Furthermore, structural biology of the viral lifecycle was hindered by the sample thickness. Here, I review the recent advances in the applications of cryo-electron tomography (cryo-ET) on enveloped viral structures and intracellular viral activities.


Subject(s)
Electron Microscope Tomography , Viruses , Animals , Cryoelectron Microscopy/methods , Electron Microscope Tomography/methods , Lipid Bilayers , Viruses/chemistry , Viruses/metabolism
6.
Proc Natl Acad Sci U S A ; 120(18): e2213332120, 2023 05 02.
Article in English | MEDLINE | ID: mdl-37094167

ABSTRACT

Among the current five Variants of Concern, infections caused by SARS-CoV-2 B.1.617.2 (Delta) variant are often associated with the greatest severity. Despite recent advances on the molecular basis of elevated pathogenicity using recombinant proteins, the architecture of intact Delta virions remains veiled. Moreover, pieces of molecular evidence for the detailed mechanism of S-mediated membrane fusion are missing. Here, we showed the pleomorphic nature of Delta virions from electron beam inactivated samples and reported the in situ structure and distribution of S on the authentic Delta variant. We also captured the virus-virus fusion events, which provided pieces of structural evidence for Delta's attenuated dependency on cellular factors for fusion activation, and proposed a model of S-mediated membrane fusion. Besides, site-specific glycan analysis revealed increased oligomannose-type glycosylation of native Delta S than that of the WT S. Together, these results disclose distinctive factors of Delta being the most virulent SARS-CoV-2 variant.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , Membrane Fusion , Glycosylation , Spike Glycoprotein, Coronavirus
7.
Proc Natl Acad Sci U S A ; 119(42): e2211568119, 2022 10 18.
Article in English | MEDLINE | ID: mdl-36215487

ABSTRACT

Eukaryotic DNA replication is initiated at multiple chromosomal sites known as origins of replication that are specifically recognized by the origin recognition complex (ORC) containing multiple ATPase sites. In budding yeast, ORC binds to specific DNA sequences known as autonomously replicating sequences (ARSs) that are mostly nucleosome depleted. However, nucleosomes may still inhibit the licensing of some origins by occluding ORC binding and subsequent MCM helicase loading. Using purified proteins and single-molecule visualization, we find here that the ORC can eject histones from a nucleosome in an ATP-dependent manner. The ORC selectively evicts H2A-H2B dimers but leaves the (H3-H4)2 tetramer on DNA. It also discriminates canonical H2A from the H2A.Z variant, evicting the former while retaining the latter. Finally, the bromo-adjacent homology (BAH) domain of the Orc1 subunit is essential for ORC-mediated histone eviction. These findings suggest that the ORC is a bona fide nucleosome remodeler that functions to create a local chromatin environment optimal for origin activity.


Subject(s)
Nucleosomes , Origin Recognition Complex , Adenosine Triphosphatases/metabolism , Adenosine Triphosphate , Chromatin , DNA/metabolism , DNA Replication , Histones/metabolism , Nucleosomes/genetics , Origin Recognition Complex/metabolism , Replication Origin
8.
Small ; 20(32): e2311862, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38501876

ABSTRACT

In recent years, the research of FeSe2 and its composites in environmental remediation has been gradually carried out. And the FeSe2 materials show great catalytic performance in photocatalysis, electrocatalysis, and Fenton-like reactions for pollutants removal. Therefore, the studies and applications of FeSe2 materials are reviewed in this work, including the common synthesis methods, the role of Fe and Se species as well as the catalyst structure, and the potential for practical environmental applications. Hereinto, it is worth noting in particular that the lower-valent Se (Se2-), unsaturated Se (Se-), and Se vacancies (VSe) can play different roles in promoting pollutants removal. In addition, the FeSe2 material also demonstrates high stability, reusability, and adaptability over a wider pH range as well as universality to different pollutants. In view of the overall great properties and performance of FeSe2 materials compared with other typical Fe-based materials, it deserves and needs further research. And finally, this paper presents some challenges and perspectives in future development, looking forward to providing helpful guidance for the subsequent research of FeSe2 and its composites for environmental application.

9.
Small ; : e2401970, 2024 May 21.
Article in English | MEDLINE | ID: mdl-38770987

ABSTRACT

Transition metal compounds (TMCs) have long been potential candidate catalysts in persulfate-based advanced oxidation process (PS-AOPs) due to their Fenton-like catalyze ability for radical generation. However, the mechanism involved in TMCs-catalyzed nonradical PS-AOPs remains obscure. Herein, the growth of FeO on the Fe3O4/carbon precursor is regulated by restricted pyrolysis of MIL-88A template to activate peroxymonosulfate (PMS) for tetracycline (TC) removal. The higher FeO incorporation conferred a 2.6 times higher degradation performance than that catalyzed by Fe3O4 and also a higher interference resistance to anions or natural organic matter. Unexpectedly, the quenching experiment, probe method, and electron paramagnetic resonance quantitatively revealed that the FeO reassigned high nonradical species (1O2 and FeIV═O) generation to replace original radical system created by Fe3O4. Density functional theory calculation interpreted that PMS molecular on strongly-adsorbed (200) and (220) facets of FeO enjoyed unique polarized electronic reception for surface confinement effect, thus the retained peroxide bond energetically supported the production of 1O2 and FeIV═O. This work promotes the mechanism understanding of TMCs-induced surface-catalyzed persulfate activation and enables them better perform catalytic properties in wastewater treatment.

10.
Small ; : e2403941, 2024 Jul 26.
Article in English | MEDLINE | ID: mdl-39058224

ABSTRACT

Photo-responsive materials have garnered significant interest for their ability to react to non-contact stimuli, though achieving self-healing under gentle conditions remains an elusive goal. In this research, an innovative and straightforward approach for synthesizing silicone elastomers is proposed that not only self-heal at room temperature but also possess unique photochromic properties and adjustable mechanical strength, along with being both transparent and reprocessable. Initially, aldehyde-bifunctional dithiophene-ethylene molecules with dialdehyde groups (DTEM) and isocyanurate (IPDI) is introduced into the aminopropyl-terminated polydimethylsiloxane (H2N-PDMS-NH2) matrix. Subsequently, palladium is incorporated to enhance coordination within the matrix. These silicone elastomers transition to a blue state under 254 nm UV light and revert to transparency under 580 nm light. Remarkably, they demonstrate excellent thermal stability at temperatures up to 100 °C and show superior fatigue resistance. The optical switching capabilities of the silicone elastomers significantly affect both their mechanical characteristics and self-healing abilities. Notably, the PDMS-DTEM-IPDI-@Pd silicone elastomer, featuring closed-loop photo-switching molecules, exhibits a fracture toughness that is 1.3 times greater and a room temperature self-healing efficiency 1.4 times higher than its open-loop counterparts. This novel photo-responsive silicone elastomer offers promising potential for applications in data writing and erasure, UV protective coatings, and micro-trace development.

11.
Small ; : e2404488, 2024 Jul 29.
Article in English | MEDLINE | ID: mdl-39072900

ABSTRACT

A great challenge in the commercialization process of layered Ni-rich cathode material LiNixCoyMn1-x-yO2 (NCM, x ≥ 80%) for lithium-ion batteries is the surface instability, which is exacerbated by the increase in nickel content. The high surface alkalinity and unavoidable cathode/electrolyte interface side reactions result in significant decrease for the capacity of NCM material. Surface coating and doping are common and effective ways to improve the electrochemical performance of Ni-rich cathode material. In this study, an in situ reaction is induced on the surface of secondary particles of NCM material to construct a stable lithium sulfate coating, while achieving sulfur doping in the near surface region. The synergistic modification of lithium sulfate coating and lattice sulfur doping significantly reduced the content of harmful residual lithium compounds (RLCs) on the surface of NCM material, suppressed the side reactions between the cathode material surface and electrolyte and the degradation of surface structure of the NCM material, effectively improved the rate capability and cycling stability of the NCM material.

12.
J Transl Med ; 22(1): 593, 2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38918793

ABSTRACT

BACKGROUND: Sorafenib resistance is becoming increasingly common and disadvantageous for hepatocellular carcinoma (HCC) treatment. Ferroptosis is an iron dependent programmed cell death underlying the mechanism of sorafenib. Iron is crucial for synthesis of cofactors essential to mitochondrial enzymes and necessary for HCC proliferation, while mitochondrial iron overload and oxidative stress are associated with sorafenib induced ferroptosis. However, the crosstalk among iron homeostasis and sorafenib resistance is unclear. METHODS: We conducted bioinformatics analysis of sorafenib treated HCC datasets to analyze GCN5L1 and iron related gene expression with sorafenib resistance. GCN5L1 deleted HCC cell lines were generated by CRISPR technology. Sorafenib resistant HCC cell line was established to validate dataset analysis and evaluate the effect of potential target. RESULTS: We identified GCN5L1, a regulator of mitochondrial acetylation, as a modulator in sorafenib-induced ferroptosis via affecting mitochondrial iron homeostasis. GCN5L1 deficiency significantly increased sorafenib sensitivity in HCC cells by down-regulating mitochondrial iron transporters CISD1 expression to induce iron accumulation. Mitochondrial iron accumulation leads to an acceleration in cellular and lipid ROS. Sorafenib resistance is related to CISD1 overexpression to release mitochondrial iron and maintaining mitochondrial homeostasis. We combined CISD1 inhibitor NL-1 with sorafenib, which significantly enhanced sorafenib-induced ferroptosis by promoting mitochondrial iron accumulation and lipid peroxidation. The combination of NL-1 with sorafenib enhanced sorafenib efficacy in vitro and in vivo. CONCLUSIONS: Our findings demonstrate that GCN5L1/CISD1 axis is crucial for sorafenib resistance and would be a potential therapeutic strategy for sorafenib resistant HCC.


Subject(s)
Carcinoma, Hepatocellular , Drug Resistance, Neoplasm , Ferroptosis , Homeostasis , Iron , Liver Neoplasms , Mitochondria , Sorafenib , Sorafenib/pharmacology , Sorafenib/therapeutic use , Carcinoma, Hepatocellular/metabolism , Carcinoma, Hepatocellular/pathology , Carcinoma, Hepatocellular/drug therapy , Carcinoma, Hepatocellular/genetics , Liver Neoplasms/metabolism , Liver Neoplasms/pathology , Liver Neoplasms/genetics , Liver Neoplasms/drug therapy , Iron/metabolism , Humans , Homeostasis/drug effects , Mitochondria/metabolism , Mitochondria/drug effects , Cell Line, Tumor , Animals , Ferroptosis/drug effects , Drug Resistance, Neoplasm/drug effects , Drug Resistance, Neoplasm/genetics , Mice, Nude , Reactive Oxygen Species/metabolism , Mice , Gene Expression Regulation, Neoplastic/drug effects
13.
Phys Rev Lett ; 132(20): 203602, 2024 May 17.
Article in English | MEDLINE | ID: mdl-38829095

ABSTRACT

Fock states with a well-defined number of photons in an oscillator have shown a wide range of applications in quantum information science. Nonetheless, their usefulness has been marred by single and multiphoton losses due to unavoidable environment-induced dissipation. Though several dissipation engineering methods have been developed to counteract the leading single-photon-loss error, averting multiple-photon losses remains elusive. Here, we experimentally demonstrate a dissipation engineering method that autonomously stabilizes multiphoton Fock states against losses of multiple photons using a cascaded selective photon-addition operation in a superconducting quantum circuit. Through measuring the photon-number populations and Wigner tomography of the oscillator states, we observe a prolonged preservation of nonclassical Wigner negativities for the stabilized Fock states |N⟩ with N=1, 2, 3 for a duration of about 10 ms. Furthermore, the dissipation engineering method demonstrated here also facilitates the implementation of a nonunitary operation for resetting a binomially encoded logical qubit. These results highlight potential applications in error-correctable quantum information processing against multiple-photon-loss errors.

14.
Phys Rev Lett ; 132(25): 250204, 2024 Jun 21.
Article in English | MEDLINE | ID: mdl-38996245

ABSTRACT

The Hamiltonian, which determines the evolution of a quantum system, is fundamental in quantum physics. Therefore, it is crucial to implement high-precision generation and measurement of the Hamiltonian in a practical quantum system. Here, we experimentally demonstrate ultrahigh-precision Hamiltonian parameter estimation with a significant quantum advantage in a superconducting circuit via sequential control. We first observe the commutation relation for noncommuting operations determined by the system Hamiltonian, both with and without adding quantum control, verifying the commuting property of controlled noncommuting operations. Based on this control-induced commuting property, we further demonstrate Hamiltonian parameter estimation for polar and azimuth angles in superconducting circuits, achieving ultrahigh metrological gains in measurement precision exceeding the standard quantum limit by up to 16.0 and 16.1 dB at N=100, respectively.

15.
Liver Int ; 44(8): 1924-1936, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38597373

ABSTRACT

BACKGROUND AND AIMS: Iron overload, oxidative stress and ferroptosis are associated with liver injury in alcohol-associated liver disease (ALD), however, the crosstalk among these regulatory pathways in ALD development is unclear. METHODS: ALD mouse model and general control of amino acid synthesis 5 like 1 (GCN5L1) liver knockout mice were generated to investigate the role of GCN5L1 in ALD development. Proteomic screening tests were performed to identify the key factors mediating GCN5L1 loss-induced ALD. RESULTS: Gene Expression Omnibus data set analysis indicates that GCN5L1 expression is negatively associated with ALD progression. GCN5L1 hepatic knockout mice develop severe liver injury and lipid accumulation when fed an alcohol diet. Screening tests identified that GCN5L1 targeted the mitochondrial iron transporter CISD1 to regulate mitochondrial iron homeostasis in ethanol-induced ferroptosis. GCN5L1-modulated CISD1 acetylation and activity were crucial for iron accumulation and ferroptosis in response to alcohol exposure. CONCLUSION: Pharmaceutical modulation of CISD1 activity is critical for cellular iron homeostasis and ethanol-induced ferroptosis. The GCN5L1/CISD1 axis is crucial for oxidative stress and ethanol-induced ferroptosis in ALD and is a promising avenue for novel therapeutic strategies.


Subject(s)
Disease Models, Animal , Ferroptosis , Liver Diseases, Alcoholic , Mice, Knockout , Oxidative Stress , Animals , Liver Diseases, Alcoholic/metabolism , Liver Diseases, Alcoholic/genetics , Liver Diseases, Alcoholic/pathology , Mice , Iron/metabolism , Liver/metabolism , Liver/pathology , Male , Ethanol , Mice, Inbred C57BL , Humans , Nerve Tissue Proteins , Mitochondrial Proteins
16.
Pharm Res ; 41(6): 1201-1216, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38834905

ABSTRACT

BACKGROUND: Some glucoside drugs can be transported via intestinal glucose transporters (IGTs), and the presence of carbohydrate excipients in pharmaceutical formulations may influence the absorption of them. This study, using gastrodin as probe drug, aimed to explore the effects of fructose, lactose, and arabic gum on intestinal drug absorption mediated by the glucose transport pathway. METHODS: The influence of fructose, lactose, and arabic gum on gastrodin absorption was assessed via pharmacokinetic experiments and single-pass intestinal perfusion. The expression of sodium-dependent glucose transporter 1 (SGLT1) and sodium-independent glucose transporter 2 (GLUT2) was quantified via RT‒qPCR and western blotting. Alterations in rat intestinal permeability were evaluated through H&E staining, RT‒qPCR, and immunohistochemistry. RESULTS: Fructose reduced the area under the curve (AUC) and peak concentration (Cmax) of gastrodin by 42.7% and 63.71%, respectively (P < 0.05), and decreased the effective permeability coefficient (Peff) in the duodenum and jejunum by 58.1% and 49.2%, respectively (P < 0.05). SGLT1 and GLUT2 expression and intestinal permeability remained unchanged. Lactose enhanced the AUC and Cmax of gastrodin by 31.5% and 65.8%, respectively (P < 0.05), and increased the Peff in the duodenum and jejunum by 33.7% and 26.1%, respectively (P < 0.05). SGLT1 and GLUT2 levels did not significantly differ, intestinal permeability increased. Arabic gum had no notable effect on pharmacokinetic parameters, SGLT1 or GLUT2 expression, or intestinal permeability. CONCLUSION: Fructose, lactose, and arabic gum differentially affect intestinal drug absorption through the glucose transport pathway. Fructose competitively inhibited drug absorption, while lactose may enhance absorption by increasing intestinal permeability. Arabic gum had no significant influence.


Subject(s)
Benzyl Alcohols , Excipients , Fructose , Glucose Transporter Type 2 , Glucose , Glucosides , Gum Arabic , Intestinal Absorption , Lactose , Rats, Sprague-Dawley , Sodium-Glucose Transporter 1 , Animals , Intestinal Absorption/drug effects , Glucosides/pharmacology , Glucosides/administration & dosage , Glucosides/pharmacokinetics , Sodium-Glucose Transporter 1/metabolism , Sodium-Glucose Transporter 1/genetics , Male , Glucose Transporter Type 2/metabolism , Glucose Transporter Type 2/genetics , Rats , Excipients/chemistry , Excipients/pharmacology , Glucose/metabolism , Lactose/chemistry , Benzyl Alcohols/pharmacology , Benzyl Alcohols/pharmacokinetics , Intestinal Mucosa/metabolism , Intestinal Mucosa/drug effects , Biological Transport/drug effects , Permeability/drug effects
17.
J Med Internet Res ; 26: e54944, 2024 Aug 28.
Article in English | MEDLINE | ID: mdl-39197165

ABSTRACT

BACKGROUND: Chronic subdural hematoma (CSDH) represents a prevalent medical condition, posing substantial challenges in postoperative management due to risks of recurrence. Such recurrences not only cause physical suffering to the patient but also add to the financial burden on the family and the health care system. Currently, prognosis determination largely depends on clinician expertise, revealing a dearth of precise prediction models in clinical settings. OBJECTIVE: This study aims to use machine learning (ML) techniques for the construction of predictive models to assess the likelihood of CSDH recurrence after surgery, which leads to greater benefits for patients and the health care system. METHODS: Data from 133 patients were amassed and partitioned into a training set (n=93) and a test set (n=40). Radiomics features were extracted from preoperative cranial computed tomography scans using 3D Slicer software. These features, in conjunction with clinical data and composite clinical-radiomics features, served as input variables for model development. Four distinct ML algorithms were used to build predictive models, and their performance was rigorously evaluated via accuracy, area under the curve (AUC), and recall metrics. The optimal model was identified, followed by recursive feature elimination for feature selection, leading to enhanced predictive efficacy. External validation was conducted using data sets from additional health care facilities. RESULTS: Following rigorous experimental analysis, the support vector machine model, predicated on clinical-radiomics features, emerged as the most efficacious for predicting postoperative recurrence in patients with CSDH. Subsequent to feature selection, key variables exerting significant impact on the model were incorporated as the input set, thereby augmenting its predictive accuracy. The model demonstrated robust performance, with metrics including accuracy of 92.72%, AUC of 91.34%, and recall of 93.16%. External validation further substantiated its effectiveness, yielding an accuracy of 90.32%, AUC of 91.32%, and recall of 88.37%, affirming its clinical applicability. CONCLUSIONS: This study substantiates the feasibility and clinical relevance of an ML-based predictive model, using clinical-radiomics features, for relatively accurate prognostication of postoperative recurrence in patients with CSDH. If the model is integrated into clinical practice, it will be of great significance in enhancing the quality and efficiency of clinical decision-making processes, which can improve the accuracy of diagnosis and treatment, reduce unnecessary tests and surgeries, and reduce the waste of medical resources.


Subject(s)
Hematoma, Subdural, Chronic , Machine Learning , Recurrence , Humans , Hematoma, Subdural, Chronic/diagnostic imaging , Hematoma, Subdural, Chronic/surgery , Retrospective Studies , Male , Female , Aged , Middle Aged , Aged, 80 and over , Postoperative Period , Radiomics
18.
Luminescence ; 39(5): e4765, 2024 May.
Article in English | MEDLINE | ID: mdl-38769927

ABSTRACT

Isovitexin is a main natural flavonoid component in various plants. Currently, the inhibitory effect of isovitexin on pancreatic lipase (PL) and its mechanism have not been elucidated yet. In the present study, we investigated the inhibitory effect of isovitexin on PL, as well as its interaction mechanism, using enzyme inhibition methods, spectroscopic analysis, and molecular simulations. Results showed that isovitexin possessed significant PL inhibitory activity, with IC50 values of 0.26 ± 0.02 mM. The interaction between isovitexin and PL was dominated by static quenching, and mainly through hydrogen bonding and hydrophobic interaction forces. Analysis of fluorescence spectroscopy confirmed that isovitexin binding altered the conformation of the PL. Circular dichroism (CD) spectrum indicated that isovitexin altered the secondary structure of PL by decreasing the α-helix content and increasing the ß-fold content. Molecular simulations further characterize the conformational changes produced by the interaction between isovitexin with PL. The performed study may provide a new insight into the inhibitory mechanism of isovitexin as a novel PL inhibitor.


Subject(s)
Apigenin , Enzyme Inhibitors , Lipase , Pancreas , Spectrometry, Fluorescence , Animals , Apigenin/chemistry , Apigenin/pharmacology , Circular Dichroism , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/chemistry , Lipase/antagonists & inhibitors , Lipase/metabolism , Lipase/chemistry , Pancreas/enzymology
19.
AAPS PharmSciTech ; 25(6): 163, 2024 Jul 13.
Article in English | MEDLINE | ID: mdl-38997614

ABSTRACT

Some glycoside drugs can be transported through intestinal glucose transporters (IGTs). The surfactants used in oral drug preparations can affect the function of transporter proteins. This study aimed to investigate the effect of commonly used surfactants, Poloxamer 188 and Tween 80, on the drug transport capacity of IGTs. Previous studies have shown that gastrodin is the optimal drug substrate for IGTs. Gastrodin was used as a probe drug to evaluate the effect of these two surfactants on intestinal absorption in SD rats through pharmacokinetic and in situ single-pass intestinal perfusion. Then, the effects of the two surfactants on the expression of glucose transporters and tight-junction proteins were examined using RT-PCR and western blotting. Additionally, the effect of surfactants on intestinal permeability was evaluated through hematoxylin-eosin staining. The results found that all experimental for Poloxamer 188 (0.5%, 2.0% and 8.0%) and Tween 80 (0.1% and 2.0%) were not significantly different from those of the blank group. However, the AUC(0-∞) of gastrodin increased by approximately 32% when 0.5% Tween 80 was used. The changes in IGT expression correlated with the intestinal absorption of gastrodin. A significant increase in the expression of IGTs was observed at 0.5% Tween 80. In conclusion, Poloxamer 188 had minimal effect on the drug transport capacity of IGTs within the recommended limits of use. However, the expression of IGTs increased in response to 0.5% Tween 80, which significantly enhanced the drug transport capacity of IGTs. However, 0.1% and 2.0% Tween 80 had no significant effect.


Subject(s)
Intestinal Absorption , Intestinal Mucosa , Poloxamer , Polysorbates , Rats, Sprague-Dawley , Surface-Active Agents , Animals , Poloxamer/pharmacology , Polysorbates/pharmacology , Rats , Intestinal Absorption/drug effects , Male , Surface-Active Agents/pharmacology , Biological Transport/drug effects , Intestinal Mucosa/metabolism , Intestinal Mucosa/drug effects , Glucose Transport Proteins, Facilitative/metabolism , Glucosides/pharmacology
20.
PLoS Pathog ; 17(3): e1009439, 2021 03.
Article in English | MEDLINE | ID: mdl-33711082

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes the global pandemic of COVID-19. SARS-CoV-2 is classified as a biosafety level-3 (BSL-3) agent, impeding the basic research into its biology and the development of effective antivirals. Here, we developed a biosafety level-2 (BSL-2) cell culture system for production of transcription and replication-competent SARS-CoV-2 virus-like-particles (trVLP). This trVLP expresses a reporter gene (GFP) replacing viral nucleocapsid gene (N), which is required for viral genome packaging and virion assembly (SARS-CoV-2 GFP/ΔN trVLP). The complete viral life cycle can be achieved and exclusively confined in the cells ectopically expressing SARS-CoV or SARS-CoV-2 N proteins, but not MERS-CoV N. Genetic recombination of N supplied in trans into viral genome was not detected, as evidenced by sequence analysis after one-month serial passages in the N-expressing cells. Moreover, intein-mediated protein trans-splicing approach was utilized to split the viral N gene into two independent vectors, and the ligated viral N protein could function in trans to recapitulate entire viral life cycle, further securing the biosafety of this cell culture model. Based on this BSL-2 SARS-CoV-2 cell culture model, we developed a 96-well format high throughput screening for antivirals discovery. We identified salinomycin, tubeimoside I, monensin sodium, lycorine chloride and nigericin sodium as potent antivirals against SARS-CoV-2 infection. Collectively, we developed a convenient and efficient SARS-CoV-2 reverse genetics tool to dissect the virus life cycle under a BSL-2 condition. This powerful tool should accelerate our understanding of SARS-CoV-2 biology and its antiviral development.


Subject(s)
COVID-19/virology , Cell Culture Techniques/methods , SARS-CoV-2/physiology , Antiviral Agents/pharmacology , Containment of Biohazards , Genome, Viral/drug effects , High-Throughput Screening Assays , Humans , SARS-CoV-2/drug effects , SARS-CoV-2/genetics , SARS-CoV-2/growth & development , Virus Replication/drug effects
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