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1.
Clin Chim Acta ; 558: 119672, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38621589

RESUMO

BACKGROUND: Thromboxane metabolites could indirectly reflect platelet activation, among which 11-dehydro-thromboxane B2 (11dhTxB2) and 11-dehydro-2, 3-dinor thromboxane B2 (11dh23dinorTxB2) are two stable metabolites that are abundant in urine, and both are closely related to disease progression and drug use. However, most clinical application studies have focused on the single indicator of 11dhTxB2. We propose an LC-MS/MS method suitable for routine clinical screening with simultaneous determination of both metabolites and conduct preliminary studies in different populations. METHODS AND RESULTS: The thromboxane metabolites were extracted by liquid-liquid extraction and determined by LC-MS/MS. Reference intervals (RI) were established in 333 healthy adults and validated in 25 patients with coronary atherosclerosis (CA). This LC-MS/MS method was over a wide quantitative range (0.1-10 µmol/L), the imprecision and accuracy were 5.2 %-11 % and 89.3 %-106.5 %, and was suitable for clinical routine quantitative screening. The 95th percentile RI of unire 11dhTxB2 was 1220 (95 % CI: 1048, 1376) pg mg Cr -1, for 11dh23dinorTxB2, RI was 908 (95 % CI: 821, 1102) pg mg Cr -1. For the first time, we found a significant correlation between 11dhTxB2 and 11dh23dinorTxB2 in both healthy adults (r = 0.67, P < 0.001) and CA patients (r = 0.77, P < 0.001). CONCLUSION: The establishment of RI provides a reference for diseases related to platelet activation and the use of drugs, and the first discovery of the correlation between 11dhTxB2 and 11dh23dinorTxB2 in urine provides a new possibilitie for the diagnostic and prognostic of cardiovascular diseases.

2.
Phytomedicine ; 128: 155475, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38492368

RESUMO

BACKGROUND: The intricate interactions between chronic psychological stress and susceptibility to breast cancer have been recognized, yet the underlying mechanisms remain unexplored. Danzhi Xiaoyao Powder (DZXY), a traditional Chinese medicine (TCM) formula, has found clinical utility in the treatment of breast cancer. Macrophages, as the predominant immune cell population within the tumor microenvironment (TME), play a pivotal role in orchestrating tumor immunosurveillance. Emerging evidence suggests that lipid oxidation accumulation in TME macrophages, plays a critical role in breast cancer development and progression. However, a comprehensive understanding of the pharmacological mechanisms and active components of DZXY related to its clinical application in the treatment of stress-aggravated breast cancer remains elusive. PURPOSE: This study sought to explore the plausible regulatory mechanisms and identify the key active components of DZXY contributing to its therapeutic efficacy in the context of breast cancer. METHODS: Initially, we conducted an investigation into the relationship between the phagocytic capacity of macrophages damaged by psychological stress and phospholipid peroxidation using flow cytometry and LC-MS/MS-based phospholipomics. Subsequently, we evaluated the therapeutic efficacy of DZXY based on the results of the tumor size, tumor weight, the phospholipid peroxidation pathway and phagocytosis of macrophage. Additionally, the target-mediated characterization strategy based on binding of arachidonate 15-lipoxygenase (ALOX15) to phosphatidylethanolamine-binding protein-1 (PEBP1), including molecular docking analysis, microscale thermophoresis (MST) assay, co-immunoprecipitation analysis and activity verification, has been further implemented to reveal the key bio-active components in DZXY. Finally, we evaluated the therapeutic efficacy of isochlorogenic acid C (ICAC) based on the results of tumor size, tumor weight, the phospholipid peroxidation pathway, and macrophage phagocytosis in vivo. RESULTS: The present study demonstrated that phospholipid peroxides, as determined by LC-MS/MS-based phospholipidomics, triggered in macrophages, which in turn compromised their capacity to eliminate tumor cells through phagocytosis. Furthermore, we elucidate the mechanism behind stress-induced PEBP1 to form a complex with ALOX15, thereby mediating membrane phospholipid peroxidation in macrophages. DZXY, demonstrates potent anti-breast cancer therapeutic effects by disrupting the ALOX15/PEBP1 interaction and inhibiting phospholipid peroxidation, ultimately enhancing macrophages' phagocytic capability towards tumor cells. Notably, ICAC emerged as a promising active component in DZXY, which can inhibit the ALOX15/PEBP1 interaction, thereby mitigating phospholipid peroxidation in macrophages. CONCLUSION: Collectively, our findings elucidate stress increases the susceptibility of breast cancer by driving lipid peroxidation of macrophages and suggest the ALOX15/PEBP1 complex as a promising intervention target for DZXY.

3.
Langmuir ; 40(12): 6463-6470, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38483327

RESUMO

Endowing paper with highly flexible, conductive, and superhydrophobic properties will effectively expand its applications in fields such as green packaging, smart sensing, and paper-based electronics. Herein, a multifunctional superhydrophobic paper is reported in which a highly flexible transparent conductive substrate is prepared by introducing a hydrophobic deep eutectic polymer into the ethylcellulose network via a matrix swelling-polymerization strategy, and then the substrate is modified using fluorinated silica to impart superhydrophobicity. By introducing soft deep eutectic polymers, (1) the superhydrophobic paper can efficiently dissipate energy during deformation, (2) intrinsically ion-conducting deep eutectic polymers can endow the material with good electrical sensing properties, and (3) meanwhile, enhanced interfacial interactions can anchor inorganic particles, thereby improving the coating stability. The prepared superhydrophobic paper has an ultrahigh water contact angle (contact angle ≈ 162.2°) and exhibits a stable electrical response signal to external deformation/pressure, and the electrical properties are almost unaffected by external water molecules. In addition, the superhydrophobic paper was able to withstand 5000 bending-recovery cycles at a large angle of 150°, exhibiting stable electrical performance. The design concepts demonstrated here will provide insights into the development of superhydrophobic paper-based flexible electronic devices.

4.
Clin Chim Acta ; 552: 117650, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37956824

RESUMO

Schizophrenia is a serious mental disease with unknown etiology that affects approximately 1 % of the population around the world. Altered levels of amino acid neurotransmitters may underlie the physiopathology of schizophrenia (SZ). This study aimed to develop a rapid and robust liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for simultaneous determination of glutamate acid (Glu), aspartic acid (Asp), γ-aminobutyric acid (GABA), glycine acid (Gly), and Taurine acid (Tau) in patients with schizophrenia plasma and establish reference intervals for Chinese adult populations, and applied to patients with schizophrenia for a preliminary exploration of changes in their plasma levels of five amino acid neurotransmitters. Sample treatment involved protein precipitation followed by dansyl chloride (DNS-Cl) derivatization and total run time is 5.8 min. The method was validated according to the latest national and international guidelines, which achieved acceptable precision (0.54-14.54 %) and accuracy (97.06-103.82 %). The reference interval for Glu, Asp, Gly, Tau, and GABA were 55.51-189.06, 27.51-92.38, 204.01-574.55, 107.50-227.65, and <1 µmol/L, respectively. Increased Tau levels and decreased Asp and Glu levels were shown in patients with schizophrenia. This method was suitable for clinical routine detection of plasma 5 amino acid neurotransmitters in Chinese adult populations.


Assuntos
Aminoácidos , Esquizofrenia , Adulto , Humanos , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Esquizofrenia/diagnóstico , Neurotransmissores/análise , Neurotransmissores/química , Ácido gama-Aminobutírico/análise , Glicina , China , Cromatografia Líquida de Alta Pressão/métodos
5.
Int J Biol Macromol ; 258(Pt 1): 128795, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38114001

RESUMO

The development of novel cellulose-based bioplastics (CBPs) is highly desirable because CBPs are green, rationally use resources, and lead to a reduction in environmental pollution compared to alternative materials. However, incorporating high transparency, water resistance, mechanical robustness, wet-adhesion, ionic conductivity and recyclability into CBP remains a challenge. In this paper, novel CBPs with supramolecular covalent networks are fabricated by introducing polymerizable hydrophobic deep eutectic solvents (HDES) into ethylcellulose (EC) networks through in situ plasticization followed by a rapid photopolymerization process. The excellent molecular interfacial compatibility enables EC to be loaded with a high content of poly(HDES), while allowing high transparency (more than 90 %) of the prepared CBPs. Multiple intermolecular interactions provide CBPs with mechanical robustness, water resistance, and underwater adhesion, and CBPs can be readily recovered by the solvent in a closed loop. Moreover, CBPs possess inherent ionic conductivities, and using them as green substrates, personalized electroluminescent devices can be successfully constructed. The method proposed in this paper provides a new strategy for the preparation of multifunctional CBPs, which will greatly enrich their applications in self-adhesive materials, green flexible electronics and other package materials.


Assuntos
Anormalidades Múltiplas , Celulose , Deficiência Intelectual , Malformações do Desenvolvimento Cortical , Água , Biopolímeros , Condutividade Elétrica
6.
Clin Chim Acta ; 553: 117709, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38103852

RESUMO

BACKGROUND: Transthyretin (TTR) gene mutations are associated with hereditary amyloidosis (ATTR) caused by mutant TTR protein dissociation, misfolding, aggregation, and insoluble fibrils deposition. Herein, we reported a chromatographic approach for quantification and identification of TTR tetramer in human blood serum by ultra performance liquid chromatography (UPLC). METHODS: TTR proteins and serum were incubated with a fluorescent TTR tetramer sensor (A2). The A2 sensor specifically reacted with tetrameric TTR and released stoichiometric fluorescence that was detected by fluorescence detector coupled to UPLC. The external standard was used for quantification, the chromatographic peak parameters were used to identification certain mutation types. RESULTS: UPLC correctly distinguished 18 types of mutant TTR proteins from wild type. The results were consistent with follow-up analysis of two ATTR patients' blood serum samples. In addition, the tetrameric TTR of 30 heart failure (HF) patients showed strongly correlation (r = -0.63, p < 0.00) with NT-proBNP, a HF clinical biomarker. CONCLUSIONS: UPLC method has sufficient accuracy to eliminate the necessity of sequencing for certain types of TTR mutations and allows for facile initial screening of ATTR amyloidosis patients, carriers, and healthy individuals for time-saving and economical purposes. TTR tetramer may serve as a diagnostic biomarker to evaluate the risk of HF diseases.


Assuntos
Neuropatias Amiloides Familiares , Insuficiência Cardíaca , Humanos , Neuropatias Amiloides Familiares/diagnóstico , Neuropatias Amiloides Familiares/genética , Neuropatias Amiloides Familiares/complicações , Cromatografia Líquida de Alta Pressão , Pré-Albumina/metabolismo , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/genética , Biomarcadores
7.
Schizophr Res ; 262: 8-17, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37918291

RESUMO

BACKGROUND: Schizophrenia is a chronic and complex severe psychiatric disorder. Male and female are different in their risks for schizophrenia for the biologic and sociocultural reasons. Homocysteine (Hcy), Cysteine (Cys), and methionine (Met) play important roles in metabolism, and the three amino acids may also be involved in pathogenesis of schizophrenia. OBJECTIVE: This study aimed to test the associations between sulfur-containing amino acid blood levels and risk of schizophrenia, evaluating the different risk in male and female. METHODS: We organized a case-control study on 876 individuals with schizophrenia and 913 age- and sex-matched healthy subjects as control group. The concentrations of Hcy, Cys and Met were measured by liquid chromatography-tandem mass spectrometry technology. Subsequently, restricted cubic spline was applied to explore full-range associations of these amino acids with schizophrenia. Interactions between levels of the three amino acids and sex on additive scale were also tested. RESULTS: Hcy levels at ≤29 µmol/L were associated with sharply increased risk of schizophrenia, inversely, Met was associated with sharply decreased risk of schizophrenia at levels ≤22 µmol/L. Increased Cys levels were associated with decreased risk of schizophrenia. Almost inverse associations were observed between Cys/Hcy and Met/Hcy ratios and schizophrenia. Significant synergistic interactions between levels of all the three amino acids and sex were discovered on an additive scale. CONCLUSIONS: Our study suggests a close association between sulfur-containing amino acids and schizophrenia with different risk in male and female. Future studies are demanded to clarify the pathogenic role of Hcy, Cys and Met in schizophrenia.


Assuntos
Esquizofrenia , Humanos , Masculino , Feminino , Esquizofrenia/epidemiologia , Estudos de Casos e Controles , Metionina , Cisteína , Racemetionina , Homocisteína , Enxofre
8.
Langmuir ; 39(38): 13649-13655, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37713388

RESUMO

Constructing green recyclable cellulose-based tapes with high transparency, mechanical robustness, and strong wet adhesion using natural components is highly desirable but challenging. Herein, novel cellulose-based self-adhesive tapes were reported by coating a polymerizable hydrophobic deep eutectic solvent (DES) on ethylcellulose followed by photopolymerization. The prepared ethylcellulose-based self-adhesive tape (ECSAT) exhibited an optical transmittance of up to ∼88% and could provide strong adhesion by interfacial intermolecular interactions without obstructing information. Due to the hydrophobic nature of the overall structure, ECSAT does not exhibit significant adhesive strength and mechanical degradation under water, acid, and alkali environments. Notably, ECSAT can be completely dissolved in the resultant DES and furthermore reused as a self-adhesive coating. The recycled ECSAT still maintained good optical transparency, mechanical strength, and wet adhesion. We believe that ECSATs with all-around performances have a wide range of applications in packaging and other engineering fields.

10.
Pharmaceuticals (Basel) ; 16(2)2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-37259301

RESUMO

Agrimonolide (AM), which is a derivative of isocoumarins, is found mainly in the herb Agrimonia pilosa Ledeb. This compound is highly lipophilic and readily crosses the blood-brain barrier. In recent years, interest has grown in the use of AM as a multitarget natural treatment for various diseases, such as cancer, inflammation, hepatic injury, myocardial damage, and diabetes mellitus. The potential mechanisms of these pharmacological effects have been clarified at cellular and molecular levels. AM shows no cytotoxicity over a range of concentrations in different types of cells, providing evidence for its good safety profile in vitro. These findings indicate that AM is a promising medicinal agent. However, most studies on AM's pharmacological activities, mechanisms of action, and safety lack substantial animal or human data. Additionally, the pharmacokinetics, metabolism, and disposition of this compound have received little attention. This review highlights the status of current information regarding the sources, properties, pharmacological effects, and safety of AM. Furthermore, potential strategies to resolve problematic issues identified in previous studies are fully discussed. This summary and analysis of the research progress of AM may inspire deeper investigations and more extensive applications of AM in the future.

11.
J Clin Invest ; 133(10)2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-37183824

RESUMO

Parkinson's disease (PD) is a neurodegenerative disorder characterized by the gradual loss of midbrain dopaminergic neurons in association with aggregation of α-synuclein. Oxidative damage has been widely implicated in this disease, though the mechanisms involved remain elusive. Here, we demonstrated that preferential accumulation of peroxidized phospholipids and loss of the antioxidant enzyme glutathione peroxidase 4 (GPX4) were responsible for vulnerability of midbrain dopaminergic neurons and progressive motor dysfunctions in a mouse model of PD. We also established a mechanism wherein iron-induced dopamine oxidation modified GPX4, thereby rendering it amenable to degradation via the ubiquitin-proteasome pathway. In conclusion, this study unraveled what we believe to be a novel pathway for dopaminergic neuron degeneration during PD pathogenesis, driven by dopamine-induced loss of antioxidant GPX4 activity.


Assuntos
Ferroptose , Doença de Parkinson , Camundongos , Animais , Dopamina/metabolismo , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Neurônios Dopaminérgicos/metabolismo , Antioxidantes , Ferroptose/genética , Doença de Parkinson/metabolismo , Mesencéfalo/metabolismo , alfa-Sinucleína/metabolismo , Ubiquitinação
13.
Bioanalysis ; 15(5): 249-258, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36976934

RESUMO

This study aimed to establish an isotope dilution LC-MS/MS method for the determination of folic acid, 5-formyltetrahydrofolate and 5-methyltetrahydrofolate in human serum. This method was then used to quantify these three folate forms in the healthy adult population and supplement users. A stable 96-well solid-phase extraction system was used to prepare serum samples. The highly sensitive method was established using a Shimadzu LCMS-8060NX. The linearity was good in the range of 0.1-10 nmol/l for folic acid and 5-formyltetrahydrofolate and 1.0-100 nmol/l for 5-methyltetrahydrofolate. The accuracy and precision were good. The method was sensitive, robust and high-throughput and could be used for the routine clinical monitoring of these three folate forms in the Chinese population.


Assuntos
Ácido Fólico , Espectrometria de Massas em Tandem , Adulto , Humanos , Cromatografia Líquida/métodos , Leucovorina , Espectrometria de Massas em Tandem/métodos , Isótopos
14.
Int J Biol Macromol ; 240: 124171, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-36966862

RESUMO

Cellulose-based functional gels have received considerable attention because of their good mechanical properties, biocompatibility, and low cost. However, the preparation of cellulose gels with self-adhesion, mechanical robustness, ionic conductivity, anti-freezing ability, and environmental stability remains a challenge. Here, gallic acid esterified microcrystalline cellulose (MCC-GA) was obtained by grafting gallic acid (GA) onto the macromolecular chains of microcrystalline cellulose (MCC) through a one-step esterification method. Then the prepared MCC-GA was dissolved in Lithium chloride/dimethyl sulfoxide (LiCl/DMSO) system and polymerized with acrylic acid (AA) to prepare a multi-functional cellulose-based organogel. The prepared MCC-GA/polyacrylic acid (PAA) organogels exhibited enhanced interfacial adhesion through hydrogen bonding, π-π interactions, and electrostatic interactions. Additionally, the MCC-GA/PAA organogels could withstand 95 % of the compressive deformation and rapidly self-recover owing to chemical cross-linking and dynamic non-covalent interactions. The organogels also exhibited excellent anti-freezing properties (up to -80 °C), solvent retention, and ionic conductivity. Considering its excellent overall performance, the MCC-GA/PAA organogel was used as an effective flexible sensor for human motion detection and is expected to play an important role in the future development of flexible bioelectronics.


Assuntos
Adesivos , Cimentos de Resina , Humanos , Celulose/química , Solventes/química , Géis
15.
Food Chem Toxicol ; 174: 113664, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36775137

RESUMO

Per- and polyfluoroalkyl substances (PFASs) are a family of highly fluorinated aliphatic substances widely used in industrial and commercial applications. This study aims to determine the inhibition of PFASs towards sulfotransferases (SULTs) activity, and trying to explain the toxicity mechanism of PFASs. In vitro recombinant SULTs-catalyzed sulfation of p-nitrophenol (PNP) was utilized as a probe reaction. The incubation system was consisted of PFASs, SULTs, PNP, 3'-phosphoadenosine-5'-phosphosulfate, MgCl2 and Tris-HCl buffer. Ultra-performance liquid chromatography was employed for analysis of the metabolites. All tested PFASs showed inhibition towards SULTs. The longer the carbon chain length of the PFASs terminated with -COOH, the higher is its capability of inhibiting SULT1A3. PFASs with -SO3H had a relatively higher ability to inhibit SULT1A3 activity than those with -COOH, -I and -OH. The inhibition kinetic parameter was 2.16 and 1.42 µM for PFOS-SULT1A1, PFTA-SULT1B1. In vitro in vivo extrapolation showed that the concentration of PFOS and PFTA in human matrices might be higher than the threshold for inducing inhibition of SULTs. Therefore, PFASs could interfere with the metabolic pathways catalyzed by SULTs in vivo. All these results will help to understand the toxicity of PFASs from the perspective of metabolism.


Assuntos
Fluorocarbonos , Sulfotransferases , Humanos , Sulfotransferases/metabolismo , Nitrofenóis , Relação Estrutura-Atividade
16.
Clin Chem Lab Med ; 61(6): 1069-1074, 2023 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-36635945

RESUMO

OBJECTIVES: Liquid chromatography-tandem mass spectrometry (LC-MS/MS) has become a common technique in clinical laboratories in recent years. Because most methods are laboratory-developed tests (LDTs), their reproducibility and quality control (QC) have been controversial. In this study, Westgard Sigma Rules were used to evaluate the analytical performance and establish an individualised internal QC (IQC) strategy for these LDTs. METHODS: Taking the LC-MS/MS LDT method for homocysteine (Hcy) as an example, the 'desirable specifications' from the Biological Variation Database were used as quality goals. Based on the external quality assessment (EQA) samples, bias was calculated and the coefficient of variation (CV) was also calculated by IQC measurements for six consecutive months. The analytical performance was evaluated by calculated sigma metrics and an IQC strategy was designed using the Westgard Sigma Rules with run size. RESULTS: Over 116 days within 6 months, a total of 850 data points were collected for each of IQC 1 and IQC 2. The monthly coefficient of variation CV% was 2.57-4.01%, which was non-significant (p-value: 0.75). The absolute bias% for IQC1 and IQC2 was 1.23 and 1.87%, respectively. The allowable total error (TEa) was selected as 15.5%, Sigma metrics were 4.02 and 4.30, and the analytical performance was 'Good'. The 13s/22s/R4s/41s multi rules (n=4, r=1) with a run size of 200 samples were suggested for the Hcy IQC scheme. The quality goal index (QGI) values were over 1.2, indicating that trueness needed to be improved. CONCLUSIONS: The analytical performance of the Hcy LC-MS/MS LDT conformed to the Six Sigma rating level, achieving 'good' (four Sigma). Clinical practice indicated that calibration bias was the primary factor affecting trueness.


Assuntos
Espectrometria de Massas em Tandem , Gestão da Qualidade Total , Humanos , Cromatografia Líquida , Reprodutibilidade dos Testes , Controle de Qualidade , Gestão da Qualidade Total/métodos
17.
Br J Clin Pharmacol ; 89(3): 1152-1161, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36260320

RESUMO

AIMS: The pharmacokinetics of levetiracetam (LEV) significantly changed during pregnancy. It is a great challenge to predict the adjusted doses of LEV to reach the preconception target concentrations. This study aimed to establish a population pharmacokinetic model of LEV in women with epilepsy (WWE) during pregnancy to analyse the factors of pharmacokinetic variability and to develop a model-based individualized dosing regimen. METHODS: A total of 166 concentration-time points from 37 WWE during pregnancy treated with LEV were collected to analyse LEV pharmacokinetics with nonlinear mixed-effects modelling. The dosing regimen was optimized by Monte Carlo simulations based on the final model. RESULTS: The LEV pharmacokinetics in pregnant WWE were best described by a 1-compartment model of first-order absorption and elimination. The population typical value of apparent clearance (CL/F) in the final model was estimated to be 3.82 L/h (95% confidence interval 3.283-4.357 L/h) with a relative standard error of 7.2%. Both total body weight (TBW) and trimester of pregnancy were significantly associated with LEV-CL/F during pregnancy; LEV-CL/F increased by 42.72% when TBW increased from 55 to 65 kg from the first trimester to the second trimester. Monte Carlo simulations showed that dosing regimens for LEV should be individualized based on the patient's TBW and trimester of pregnancy to maximize the likelihood of achieving the therapeutic range. CONCLUSION: This first population pharmacokinetic study of LEV in WWE during pregnancy supports the use of a weight-based and pregnancy-based dosing regimen and can lay a foundation for further optimizing the individualized dosing regimens.


Assuntos
Anticonvulsivantes , Epilepsia , Gravidez , Feminino , Humanos , Levetiracetam/uso terapêutico , Anticonvulsivantes/uso terapêutico , Epilepsia/tratamento farmacológico , Primeiro Trimestre da Gravidez , Método de Monte Carlo
18.
Int J Biol Macromol ; 227: 1305-1316, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36473532

RESUMO

Developing a feasible and low-cost approach to fabricate recyclable, UV-shielding, biodegradable as well as water- and oil-resistant coating for paper substance is still a challenge. Herein, novel full-biobased chitosan-derived cardanol glycidyl ether (CS-xCGE, x = 1/8, 1/4, 1/2, and 1) coatings with different contents of cardanol glycidyl ether (CGE) were developed for paper substance via the ethoxylation of cardanol and sequent addition with chitosan in a one-pot process. Benefiting from the hydrophobicity and ultraviolet resistance of CGE, the resultant CS-CGE (x = 1) coated paper exhibited not only remarkable oil resistance (kit rating value of 11/12), but also water resistance (Cobb 60 value of 5.78 g/m2), UV shielding and excellent recyclability. Compared with the uncoated paper, the mechanical properties of CS-CGE coated paper including tensile strength, folding strength, and resistance of water vapor permeability were improved 25 %, 63 %, and 73.4 %, respectively, which could be ascribed to the flexible long-alkyl chain in the structure of CS-CGE and the continuous and homogeneous CS-CGE derived film covered in paper substance. Most importantly, CS-CGE film is biodegradable when it is only buried in soil. This study affords a feasible and sustainable strategy for large-scale fabrication of full-biobased, recyclable, UV-shielding, water and oil resistant, as well as biodegradable coating for green paper-derived packaging.


Assuntos
Quitosana , Embalagem de Alimentos , Quitosana/química , Éter , Etil-Éteres , Éteres
19.
Chem Commun (Camb) ; 58(100): 13975-13978, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36458706

RESUMO

Water-insensitive self-adhesive elastomers derived from hydrophobic deep eutectic polymers (HDEPs) are reported. With the help of hydrophobic π-π interactions and dynamic hydrogen bonding networks, the HDEPs performed excellent self-adhesive properties on various materials, even in aqueous environments.


Assuntos
Elastômeros , Polímeros , Elastômeros/química , Polímeros/química , Água/química , Adesivos , Cimentos de Resina , Interações Hidrofóbicas e Hidrofílicas , Ligação de Hidrogênio
20.
Sensors (Basel) ; 22(21)2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36366084

RESUMO

Improving the level of autonomy during the landing phase helps promote the full-envelope autonomous flight capability of unmanned aerial vehicles (UAVs). Aiming at the identification of potential landing sites, an end-to-end state estimation method for the autonomous landing of carrier-based UAVs based on monocular vision is proposed in this paper, which allows them to discover landing sites in flight by using equipped optical sensors and avoid a crash or damage during normal and emergency landings. This scheme aims to solve two problems: the requirement of accuracy for runway detection and the requirement of precision for UAV state estimation. First, we design a robust runway detection framework on the basis of YOLOv5 (you only look once, ver. 5) with four modules: a data augmentation layer, a feature extraction layer, a feature aggregation layer and a target prediction layer. Then, the corner prediction method based on geometric features is introduced into the prediction model of the detection framework, which enables the landing field prediction to more precisely fit the runway appearance. In simulation experiments, we developed datasets applied to carrier-based UAV landing simulations based on monocular vision. In addition, our method was implemented with help of the PyTorch deep learning tool, which supports the dynamic and efficient construction of a detection network. Results showed that the proposed method achieved a higher precision and better performance on state estimation during carrier-based UAV landings.

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