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1.
Acc Chem Res ; 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38319799

RESUMO

ConspectusOxygen electrode catalysis is crucial for the efficient operation of clean energy devices, such as proton exchange membrane fuel cells (PEMFCs) and Zn-air batteries (ZABs). However, sluggish oxygen electrocatalysis kinetics in these infrastructures put forward impending requirements toward seeking efficient oxygen-electrode catalytic materials with a clear active-site configuration and geometrical morphology to study in depth the structure-property relationship of materials. Although transition-metal-nitrogen-carbon (M-N-C) electrocatalysts have shown great prospects currently and potential in oxygen electrocatalysis as promising platinum group metal-free catalysts, the universal pyrolysis operation in the preparation process often inevitably brings about randomness and diversity of active sites, for which it is difficult to determine the structure-activity relationship, understand the catalytic mechanism, and further improve facilities performance.Covalent organic polymers (COPs) are a class of molecular geometric constructs linked by irreversible kinetic covalent bonds through reticular chemistry. Unique structural tailorability, diverse design principles, and inherent well-defined construction in pristine COPs naturally provide a great platform to study the structure-property relationship of active sites and exhibit unique features for application. In this Account, we afford an overview of our recent attempts toward the utilization of COP materials as free-pyrolysis oxygen electrode catalysts, enabling accurate construction of oxygen electrodes with clear active site and geometrical morphology characteristics in PEMFC and ZAB devices yet without enduring any high-temperature pyrolysis treatments. Starting from the needs of modern electrocatalysis, we discussed the unique properties for the design and development of pyrolysis-free pristine COPs as high-performance oxygen electrode catalytic materials in terms of intrinsic electronic structure properties and membrane-electrode-assembly (MEA) application distinguished from pyrolysis M-N-C catalysts. First, the pyrolysis-free COP catalysts provide a viable molecular model catalyst platform, which is conducive to mechanism comprehension for the relationship between catalyst activity and structure. Second, the simple and low-energy consumption synthesis process for pyrolysis-free catalysts lays the foundation for the large-scale production of catalysts, oxygen electrodes, and even the entire stack assembly without considering numerous complicated factors as traditional pyrolytic catalysts. Besides, most traditional COPs are difficult to dissolve and solution process due to their cross-linked skeleton. Our newly developed COP materials with solution processability bring about new opportunities to the process and assemble oxygen electrodes into device. These properties are unparalleled and have not been systematically reviewed and analyzed by any research reports so far. Here, we have clarified the specific advantage and potential of pyrolysis-free COP materials as oxygen electrodes applied in PEMFC and ZAB devices in response to the latest progress and requirements of current electrocatalytic research.

2.
Pharmacol Res ; 209: 107415, 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39306021

RESUMO

Neonicotinoid insecticides (NEOs) have garnered global attention due to their selective toxicity to insects and minimal impact on mammals. However, growing concerns about their extensive use and potential adverse effects on the ecological environment and non-target organisms necessitate further investigation. This study utilized bibliometric tools to analyze Web of Science data from 2003 to 2024, elucidating the current research landscape, identifying key research areas, and forecasting future trends related to NEOs. This paper provides an in-depth analysis of NEO exposure in non-target organisms, including risk assessments for various samples and maximum residue limits established by different countries. Additionally, it examines the impacts and mechanisms of NEOs on non-target organisms. Finally, it reviews the current methods for NEO removal and degradation. This comprehensive analysis provides valuable insights for regulating NEO usage and addressing associated exposure challenges.

3.
Macromol Rapid Commun ; : e2400442, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39108052

RESUMO

Non-precious metal-based nitrogen-doped carbon (M-Nx/C) shows great potential as a substitute for precious metal Pt-based catalysts. However, the conventional pyrolytic methods for forming M-Nx/C active sites are prone to issues such as the lack of synergistic interactions among bimetallic atoms and the potential encasement of active sites, leading to compromised catalytic efficiency and hindered mass transfer. In this work, a highly active FeCo-N-C@U-AC electrocatalyst is developed with a high density of active sites, adequate exposure of catalytic sites, and robust mass transfer capability using the chemical vapor-phase deposition (CVD) technique. The resulting catalyst demonstrates impressive oxygen reduction reaction (ORR) catalytic performance and stability, with half-wave potentials of 0.820 V (0.1 M HClO4) and 0.911 V (0.1 M KOH), respectively. It also exhibits significantly enhanced stability, retaining 93.25% and 98.38% of current after continuous 50 000 s of durability testing, surpassing the retention rates of Pt/C (80.31% in HClO4 and 84.96% in KOH electrolytes). Notably, when employed as a cathode catalyst in proton exchange membrane fuel cells (PEMFCs) and zinc-air flow batteries (ZAFBs), the FeCo-N-C@U-AC catalyst delivers peak power densities of 859 and 162 mW·cm-2, respectively, showcasing competitive performance comparable to benchmark Pt/C.

4.
Clin Exp Dermatol ; 49(11): 1330-1337, 2024 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-38618759

RESUMO

BACKGROUND: Chloasma is a common skin hyperpigmentation condition, with treatment options ranging from topical agents to advanced interventions such as chemical peels and laser therapy. Salicylic acid, including its supramolecular form (SSA), has shown promise in managing chloasma. However, to date, no multicentre randomized controlled trial of SSA for chloasma is available. OBJECTIVES: The purpose of this study was to assess the efficacy and safety of 30% SSA combined with 10% niacinamide in treating -chloasma. METHODS: This multicentre (n = 15), randomized, double-blind, parallel placebo-controlled trial (Clinical trial registration number: ChiCTR2200065346) enrolled and randomized 300 participants (1 : 1) to either 30% SSA treatment or placebo, with 150 allocated to treatment and 150 to placebo in the full analysis set, and 144 to treatment and 147 to placebo in the per-protocol set. A Visia® Skin Analysis System was used at each visit to assess the degree of improvement in chloasma lesions. The primary endpoint was the effective rate after 16 weeks, assessed using the modified Melasma Area and Severity Index (mMASI) score [(pretreatment score - post-treatment score)/pretreatment score × 100%]. RESULTS: The total mMASI score, overall score on the Griffiths 10-point scale, and Griffiths 10 score for the left and the right sides of the face were significantly lower in the 30% SSA group than in the placebo group (all P < 0.001). One study of drug-related adverse events (AEs) and one study of drug-unrelated AEs were reported in the 30% SSA group. No AE was reported in the placebo group. CONCLUSIONS: Among our patients, 30% SSA combined with 10% niacinamide was shown to be effective and safe for treating chloasma.


Assuntos
Niacinamida , Ácido Salicílico , Humanos , Niacinamida/uso terapêutico , Niacinamida/efeitos adversos , Niacinamida/administração & dosagem , Método Duplo-Cego , Feminino , Adulto , Masculino , Pessoa de Meia-Idade , Ácido Salicílico/uso terapêutico , Ácido Salicílico/administração & dosagem , Ácido Salicílico/efeitos adversos , Quimioterapia Combinada , Resultado do Tratamento , Melanose/tratamento farmacológico , Adulto Jovem
5.
J Eur Acad Dermatol Venereol ; 38 Suppl 6: 26-36, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38419560

RESUMO

BACKGROUND: Noninvasive energy-based device (NI-EBD) aesthetic procedures has recently gained widespread usage for treating various skin conditions, enhancing skin texture and performing rejuvenation-related procedures. However, practically all NI-EBD procedures result in variable degrees of damage to the skin barrier, inducing pathological and physiological processes such as oxidative stress and inflammation, and only a small percentage of individuals possess the innate ability to restore it. OBJECTIVE: To introduce the concept of integrated skincare and establish standardized operational procedures for perioperative integrated skincare, and furnish a theoretical basis for clinical diagnosis and treatment performed by professional medical aestheticians. METHODS: The author leveraged domestic and international guidelines, clinical practice expertise and evidence-based research, adapting them to suit the specific circumstances in China. RESULTS: The consensus were provided four parts, including concept and essence of integrated skincare, integrated skincare significance during the perioperative phase of NI-EBD procedures, active ingredients and functions of effective skincare products, standardized perioperative skincare procedure for NI-EBD procedures and precautions. For the standardized perioperative skincare procedure, four recommendations were listed according to different stages during NI-EBD procedures. CONCLUSION: These recommendations create the 'Expert Consensus on Perioperative Integrated Skincare for Noninvasive Energy-Based Device Aesthetic Procedures in Clinical Practice in China'.


Assuntos
Técnicas Cosméticas , Humanos , China , Assistência Perioperatória , Consenso , Rejuvenescimento , Higiene da Pele/métodos , Envelhecimento da Pele , Estética
6.
Altern Ther Health Med ; 30(2): 178-182, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37883753

RESUMO

Objective: This study aims to compare the efficacy and safety of drug-coated balloon (DCB) and standard angioplasty balloon (SAB) in the treatment of intrastent restenosis (ISR) after lower extremity ASO following rotarex thrombus removal. Methods: 94 patients with ISR after lower extremity ASO were selected and divided into DCB group (47 cases) and SAB group (47 cases). After patients were treated with DCB and SAB methods, six months after discharge care, the therapeutic effect, lower extremity dorsal arterial blood flow, ankle-brachial index, lameness distance, hemorheology, endothelial function indexes, and lipid levels were measured. Results: DCB group showed significantly higher effective rate compared to SAB group (P < .05). After treatment, post-treatment improvements in dorsalis arterial blood flow, ankle-brachial index intermittent claudicity distance, high-density lipoprotein cholesterol (HDL-C) and nitric oxide (NO) contents were more pronounced in the DCB group than SAB group (P < .05).Indexes of hemorheology and the contents of total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), and endothelin-1 (ET-1) levels significantly decreased after treatment, with greater reduction observed in DCB group (P < .05). In addition, No significant change in adverse reactions between groups, but DCB group had lower adverse drug reaction rate. Conclusions: Overall, DCB demonstrated superior efficacy in treating ISR after lower extremity ASO, offering a promising option for improving patient outcomes.


Assuntos
Angioplastia com Balão , Trombose , Humanos , Idoso , Resultado do Tratamento , Angioplastia com Balão/efeitos adversos , Extremidade Inferior , Colesterol , Trombose/etiologia
7.
AJR Am J Roentgenol ; 220(6): 817-825, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36752371

RESUMO

BACKGROUND. Abbreviated protocols could allow wider adoption of MRI in patients undergoing breast cancer neoadjuvant chemotherapy (NAC). However, abbreviated MRI has been explored primarily in screening settings. OBJECTIVE. The purpose of this article was to compare diagnostic performance of abbreviated MRI and full-protocol MRI for evaluation of breast cancer NAC response, stratifying by radiologists' breast imaging expertise. METHODS. This retrospective study included 203 patients with breast cancer (mean age, 52.1 ± 11.2 [SD] years) from two hospitals who underwent MRI before NAC initiation and after NAC completion before surgical resection from March 2017 to April 2021. Abbreviated MRI was extracted from full-protocol MRI and included the axial T2-weighted sequence and precontrast and single early postcontrast T1-weighted sequences. Three general radiologists and three breast radiologists independently interpreted abbreviated and full-protocol MRI in separate sessions, identifying enhancing lesions to indicate residual tumor and measuring lesion size. The reference standard was presence and size of residual tumor on pathologic assessment of post-NAC surgical specimens. RESULTS. A total of 50 of 203 patients had pathologic complete response (pCR). Intraobserver and interobserver agreement for abbreviated and full-protocol MRI for general and breast radiologists ranged from substantial to nearly perfect (κ = 0.70-0.81). Abbreviated MRI compared with full-protocol MRI showed no significant difference for general radiologists in sensitivity (54.7% vs 57.3%, p > .99), specificity (92.8% vs 95.6%, p = .29), or accuracy (83.4% vs 86.2%, p = .30), nor for breast radiologists in sensitivity (60.0% vs 61.3%, p > .99), specificity (94.6% vs 97.4%, p = .22), or accuracy (86.0% vs 88.5%, p = .30). Sensitivity, specificity, and accuracy were not significantly different between protocols for any reader individually (p > .05). Mean difference in residual tumor size on MRI relative to pathology for abbreviated protocol ranged for general radiologists from -0.19 to 0.03 mm and for breast radiologists from -0.15 to -0.05 mm, and for full protocol ranged for general radiologists from 0.57 to 0.65 mm and for breast radiologists from 0.66 to 0.79 mm. CONCLUSION. Abbreviated compared with full-protocol MRI showed similar intraobserver and interobserver agreement and no significant difference in diagnostic performance. Full-protocol MRI but not abbreviated MRI slightly overestimated pathologic tumor sizes. CLINICAL IMPACT. Abbreviated protocols may facilitate use of MRI for post-NAC response assessment by general and breast radiologists.


Assuntos
Neoplasias da Mama , Humanos , Adulto , Pessoa de Meia-Idade , Feminino , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/cirurgia , Estudos Retrospectivos , Terapia Neoadjuvante , Neoplasia Residual , Imageamento por Ressonância Magnética/métodos
8.
Environ Res ; 238(Pt 2): 117268, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37776938

RESUMO

Heavy computational load inhibits the application of groundwater contaminant numerical model to groundwater pollution source identification, remediation design, and uncertainty analysis, since a large number of model runs are required for these applications. Machine learning-based surrogate models are an effective approach to enhance the efficiency of the numerical models, and have recently attracted considerable attention in the field of groundwater contaminant modeling. Here, we review 120 research articles on machine learning-based surrogate models for groundwater contaminant modeling that were published between 1994 and 2022. We outline the state of the art method, identify the most significant research challenges, and suggest potential future directions. The six major applications of machine learning-based surrogate models are groundwater pollution source identification, groundwater remediation design, coastal aquifer management, uncertainty analysis of groundwater, groundwater monitoring network design, and groundwater transport parameters inversion. Together, these account for more than 90% of the studies we review. Latin hypercube sampling (LHS) is the most widely used sampling method, and artificial neural networks (ANNs) and Kriging are the two most widely used methods for constructing surrogate model. No method is universally superior, the advantages and disadvantages of different methods, as well as the applicability of these methods for different application purposes of groundwater contaminant modeling were analyzed. Some recommendations on the method selection for various application fields are given based on the reviews and experiences. Based on our review of the state-of-the-art, we suggest several future research directions to enhance the feasibility of the machine learning-based surrogate models of groundwater contaminant modeling: the alleviation of the curse of dimensionality, enhancing transferability, practical applications for real case studies, multi-source dada fusion, and real-time monitoring and prediction.


Assuntos
Água Subterrânea , Modelos Teóricos , Aprendizado de Máquina , Poluição Ambiental , Redes Neurais de Computação
9.
J Dairy Sci ; 106(1): 75-83, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36400617

RESUMO

Pasteurization is carried out in dairy industries to kill harmful bacteria present in raw milk. However, endospore-forming bacteria, such as Bacillus, cannot be completely eliminated by pasteurization. In this study, a total of 114 Bacillus strains were isolated from 133 pasteurized milk samples. Antibiotic susceptibility tests showed that the percentage of Bacillus with intrinsic resistance to ampicillin and penicillin were 80 and 86%, respectively. Meanwhile, some Bacillus isolates had acquired resistance, including trimethoprim-sulfamethoxazole resistance (10 isolates), clindamycin resistance (8 isolates), erythromycin resistance (2 isolates), and tetracycline resistance (1 isolate). To further locate these acquired resistance genes, the plasmids were investigated in these 16 Bacillus strains. The plasmid profile indicated that Bacillus cereus BA008, BA117, and BA119 harbored plasmids, respectively. Subsequently, the Illumina Novaseq PE150 was applied for the genomic and plasmid DNA sequencing. Notably, the gene tetL encoding tetracycline efflux protein was found to be located on plasmid pBC46-TL of B. cereus BA117. In vitro conjugative transfer indicated that pBC46-TL can be transferred into Bacillus invictae BA142, Bacillus safensis BA143, and Bacillus licheniformis BA130. The frequencies were of 1.5 × 10-7 to 1.7 × 10-5 transconjugants per donor cells. Therefore, Bacillus strains with acquired antibiotic resistance may represent a potential risk for the spread of antibiotic resistance between Bacillus and other clinical pathogens via horizontal gene transfer.


Assuntos
Bacillus , Leite , Animais , Leite/microbiologia , Prevalência , Resistência Microbiana a Medicamentos , Bacillus/genética , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana/veterinária
10.
J Allergy Clin Immunol ; 149(2): 610-623, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34224786

RESUMO

BACKGROUND: Local immunoglobulin hyperproduction is observed in nasal polyps (NPs) with and without ectopic lymphoid tissues (eLTs). OBJECTIVE: Our aim was to identify the T-cell subsets involved in local immunoglobulin production independent of eLTs in NPs. METHODS: The localization, abundance, and phenotype of CD4+ T-cell subsets were studied by immunofluorescence, flow cytometry, and single-cell RNA sequencing. Purified nasal T-cell subsets were cultured with autologous peripheral naive B cells to explore their function. Programmed death ligand 1 and programmed death ligand 2 expression in NPs was investigated by immunofluorescence staining and flow cytometry. RESULTS: Accumulation of PD-1highCXCR5-CD4+ T cells outside lymphoid aggregates was found in NPs. Nasal PD-1highCXCR5-CD4+ T cells were characterized by a unique phenotype that was related to B-cell help and tissue residency and distinct from PD-1-/intCXCR5- and CXCR5+ CD4+ T cells in NPs as well as PD-1highCXCR5highCD4+ follicular helper T cells in tonsils. Compared with the frequencies of PD-1highCXCR5-CD4+ T cells and their IFN-γ+, IL-17A+, and IL-21+ subsets in the control inferior turbinate tissues, the frequencies of these cells and their subsets were increased in both eosinophilic and noneosinophilic NPs, whereas the frequencies of the IL-4+ and IL-4+IL-21+ subsets were increased only in eosinophilic NPs. Nasal PD-1highCXCR5-CD4+ T cells induced immunoglobulin production from B cells in a potency comparable to that induced by tonsillar follicular helper T cells. PD-1highCXCR5-CD4+ T-cell frequencies were correlated with IgE levels in eosinophilic NPs. PD-L1 and PD-L2 suppressed the function of PD-1highCXCR5-CD4+ T cells, and their levels were reduced in NPs. PD-1highCXCR5-CD4+ T-cell abundance was associated with the postsurgical relapse of NPs. CONCLUSION: PD-1highCXCR5-CD4+ T cells participate in local immunoglobulin production independent of eLTs in NPs.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Imunoglobulinas/biossíntese , Pólipos Nasais/imunologia , Receptor de Morte Celular Programada 1/análise , Receptores CXCR5/análise , Antígeno B7-H1/análise , Células Cultivadas , Humanos , Interleucina-4/biossíntese , Proteína 2 Ligante de Morte Celular Programada 1/análise
11.
Angew Chem Int Ed Engl ; 62(16): e202215441, 2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-36625776

RESUMO

The structural diversity of active sites resulting from traditional pyrolysis hinder our understanding of the local coordination environment (LCE) around the active site, and its effects on performance in the oxygen reduction reaction (ORR). We created a series of FeN4 active-site configurations via a pyrolysis-free approach where LCEs are defined by covalent organic polymers (COPs). Our results suggest a more positive charge on iron atoms in the vicinity of an electron-withdrawing side-chain; that is, a high-valence configuration (FeH+ N4 ) that is achieved with a COPBTC @Cl-CNTs catalyst subject to d z 2 ${{d}_{{z}^{2}}}$ -orbital tuning. A new descriptor ξ, defined as the band center of iron atoms projected on the 3 d z 2 ${{3d}_{{z}^{2}}}$ -orbital, was introduced to quantitively explain a volcano-like regulation mechanism. When ξ is distributed between -1.887 and -1.862 eV, the catalytic performance of the COPBTC @Cl-CNTs electrocatalyst is optimized.

12.
BMC Plant Biol ; 22(1): 31, 2022 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-35027009

RESUMO

BACKGROUND AND OBJECTIVE: Salt stress is one of the most important abiotic stresses affecting the yield and quality of tobacco (Nicotiana tabacum). Thymol (a natural medicine) has been widely used in medical research because of its antibacterial and anti-inflammatory activities. However, the influence of thymol on the root growth of tobacco is not fully elucidated. In this study, the regulatory effects of different concentrations of thymol were investigated. METHODOLOGY: Here, histochemical staining and biochemical methods, non-invasive micro-test technology (NMT), and qPCR assay were performed to investigate the effect of thymol and mechanism of it improving salinity tolerance in tobacco seedlings. RESULTS: In this study, our results showed that thymol rescued root growth from salt stress by ameliorating ROS accumulation, lipid peroxidation, and cell death. Furthermore, thymol enhanced contents of NO and GSH to repress ROS accumulation, further protecting the stability of the cell membrane. And, thymol improved Na+ efflux and the expression of SOS1, HKT1, and NHX1, thus protecting the stability of Na+ and K+. CONCLUSION: Our study confirmed the protecting effect of thymol in tobacco under salt stress, and we also identified the mechanism of it, involving dynamic regulation of antioxidant system and the maintenance of Na+ homeostasis. It can be a new method to improve salinity tolerance in plants.


Assuntos
Glutationa/metabolismo , Nicotiana/crescimento & desenvolvimento , Nicotiana/metabolismo , Óxido Nítrico/metabolismo , Tolerância ao Sal/efeitos dos fármacos , Sódio/metabolismo , Timol/metabolismo , Timol/farmacologia , Produtos Agrícolas/efeitos dos fármacos , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/metabolismo , Transporte de Íons/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Nicotiana/efeitos dos fármacos
13.
Small ; 18(21): e2201197, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35491510

RESUMO

The transition-metal nitrogen-carbon (M-N-C) catalysts, as one of the optimal bifunctional oxygen catalysts, are vital for cathodic oxygen electrode of Zn-based air flow batteries (ZAFBs). However, chemical complexity of M-N-C catalysts prepared via the traditional pyrolytic process increases the difficulties of precise control toward configuration and repeatability, especially in large-scale synthesis. Herein, a bifunctional oxygen catalyst via a pyrolysis-free approach based on closed π-conjugated covalent organic polymers (COPs, microwave synthesis) is developed, which inherits the advantage of the well-defined configuration in an atomic manner. Profited from distinct catalytic centers and strong electronic coupling at the interface between COP and layered double hydroxides, the as-synthesized catalyst not only more easily permits large quantity production (>1 kg per batch), but also maintains an ultrahigh bifunctional activity and a long cycle stability even after scale synthesis (ΔE [Ej10 - E1/2 ] = 591 mV; energy efficiency drops by only 2.02% after 1200 cycles), which overwhelmingly exceeds the benchmark Pt/C+IrO2 and the state-of-the-art pyrolytic bifunctional M-N-C oxygen catalysts.

14.
J Med Virol ; 94(5): 2108-2125, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35032057

RESUMO

Variants of SARS-CoV-2 continue to emerge, posing great challenges in outbreak prevention and control. It is important to understand in advance the impact of possible variants of concern (VOCs) on infectivity and antigenicity. Here, we constructed one or more of the 15 high-frequency naturally occurring amino acid changes in the receptor-binding domain (RBD) of Alpha, Beta, and Gamma variants. A single mutant of A520S, V367F, and S494P in the above three VOCs enhanced infectivity in ACE2-overexpressing 293T cells of different species, LLC-MK2 and Vero cells. Aggregation of multiple RBD mutations significantly reduces the infectivity of the possible three VOCs. Regarding neutralization, it is noteworthy that E484K, N501Y, K417N, and N439K predispose to monoclonal antibodies (mAbs) protection failure in the 15 high-frequency mutations. Most importantly, almost all possible VOCs (single RBD mutation or aggregation of multiple mutations) showed no more than a fourfold decrease in neutralizing activity with convalescent sera, vaccine sera, and immune sera of guinea pigs with different immunogens, and no significant antigenic drift was formed. In conclusion, our pseudovirus results could reduce the concern that the aggregation of multiple high-frequency mutations in the RBD of the spike protein of the three VOCs would lead to severe antigenic drift, and this would provide value for vaccine development strategies.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Anticorpos Neutralizantes , Deriva e Deslocamento Antigênicos , COVID-19/terapia , Chlorocebus aethiops , Cobaias , Humanos , Imunização Passiva , Mutação , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus , Células Vero , Soroterapia para COVID-19
15.
BMC Public Health ; 22(1): 127, 2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-35042501

RESUMO

BACKGROUND: Subjective cognitive decline (SCD) may be the first symptomatic manifestation of Alzheimer's disease, but information on its health correlates is still sparse in Chinese older adults. This study aimed to estimate SCD symptoms and its association with socio-demographic characteristics, common chronic diseases among southern Chinese older adults. METHODS: Participants aged 60 years and older from 7 communities and 2 nursing homes in Guangzhou were recruited and interviewed with standardized assessment tools. Pittsburgh Sleep Quality Index (PSQI), Patient Health Questionnaire-9 (PHQ-9) and Generalized Anxiety Disorder-7 (GAD-7) were used to measure poor sleep quality, depression symptoms and anxiety symptoms. The SCD symptoms were measured by SCD questionnaire 9 (SCD-Q9) which ranged from 0 to 9 points, with a higher score indicating increased severity of the SCD. Participants were divided into low score group (SCD-Q9 score ≤ 3) and higher score group (SCD-Q9 score > 3). Chi-square tests and multivariate logistic regression analysis were used for exploring the influences of different characteristics of socio-demographic and lifestyle factors on SCD symptoms. Univariate and multivariate logistic regression analysis were applied to explore the association between SCD symptoms with common chronic diseases. RESULTS: A total of 688 participants were included in our analysis with a mean age of 73.79 (SD = 8.28, range: 60-101), while 62.4% of the participants were females. The mean score of the SCD-Q9 was 3.81 ± 2.42 in the whole sample. A total of 286 participants (41.6%) were defined as the low score group (≤3 points), while 402 participants (58.4%) were the high score group (> 3 points). Multivariate logistic regression analysis revealed that female (OR = 1.99, 95%CI: 1.35-2.93), primary or lower education level (OR = 2.58, 95%CI: 1.38-4.83), nursing home (OR = 1.90, 95%CI: 1.18-3.05), napping habits (OR = 1.59, 95%CI: 1.06-2.40), urolithiasis (OR = 2.72, 95%CI: 1.15-6.40), gout (OR = 2.12, 95%CI: 1.14-3.93), poor sleep quality (OR = 1.93, 95%CI: 1.38-2.71), depression symptoms (OR = 3.01, 95%CI: 1.70-5.34) and anxiety symptoms (OR = 3.11, 95%CI: 1.29-7.46) were independent positive related to high SCD-Q9 score. On the other hand, tea-drinking habits (OR = 0.64, 95%CI: 0.45-0.92), current smoking (OR = 0.46, 95%CI: 0.24-0.90) were independent negative related to high SCD-Q9 score. CONCLUSIONS: Worse SCD symptoms were closely related to common chronic diseases and socio-demographic characteristics. Disease managers should pay more attention to those factors to early intervention and management for SCD symptoms among southern Chinese older adults.


Assuntos
Disfunção Cognitiva , Distúrbios do Início e da Manutenção do Sono , Idoso , Ansiedade , China/epidemiologia , Doença Crônica , Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/psicologia , Demografia , Feminino , Humanos , Pessoa de Meia-Idade
16.
Med Sci Monit ; 27: e931969, 2021 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-34455415

RESUMO

BACKGROUND Midfoot deformity and injury can affect the internal pressure distribution of the foot. This study aimed to use 3D finite element and biomechanical analyses of midfoot von Mises stress levels in flatfoot, clubfoot, and Lisfranc joint injury. MATERIAL AND METHODS Normal feet, flatfeet, clubfeet (30 individuals each), and Lisfranc injuries (50 individuals) were reconstructed by CT, and 3D finite element models were established by ABAQUS. Spring element was used to simulate the plantar fascia and ligaments and set hyperelastic coefficients in encapsulated bone and ligaments. The stance phase was simulated by applying 350 N on the top of the talus. The von Mises stress of the feet and ankle was visualized and analyzed. RESULTS The von Mises stress on healthy feet was higher in the lateral metatarsal and ankle bones than in the medial metatarsal bone. Among the flatfoot group, the stress on the metatarsals, talus, and navicular bones was significantly increased compared with that on healthy feet. Among patients with clubfeet, stress was mainly concentrated on the talus, and stress on the lateral metatarsal and navicular bones was significantly lower. The von Mises stress on the fractured bone was decreased, and the stress on the bone adjacent to the fractured bone was higher in Lisfranc injury. During bone dislocation alone or fracture accompanied by dislocation, the von Mises stress of the dislocated bone tended to be constant or increased. CONCLUSIONS Prediction of von Mises stress distribution may be used clinically to evaluate the effects of deformity and injury on changes in structure and internal pressure distribution on the midfoot.


Assuntos
Pé Torto Equinovaro/fisiopatologia , Análise de Elementos Finitos/estatística & dados numéricos , Pé Chato/fisiopatologia , Traumatismos do Pé/fisiopatologia , Articulações do Pé/fisiopatologia , Artropatias/fisiopatologia , Estresse Mecânico , Adulto , Fenômenos Biomecânicos , Feminino , Seguimentos , Articulações do Pé/lesões , Humanos , Masculino , Prognóstico
17.
Curr Microbiol ; 78(4): 1590-1601, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33686505

RESUMO

Docynia indica is used as a plant resource for both medicine and food in minority areas of southwestern China and Southeast of Asia, especially Docynia indica leaves, which are often used as a kind of functional tea in daily life. In our previous research, it has found that D. indica is rich in polyphenols (mainly phlorizin (PHZ)). Although PHZ is the first polyphenolic competitive inhibitor of sodium-dependent glucose transporters (SGLTs) to be discovered, the promotion and application of PHZ are limited due to its extremely low bioavailability. As a kind of aglycons, phloretin (PHT) possesses a better bioavailability and bioactivity than PHZ. Therefore, the conversion of PHZ to PHT in D. indica leaves by the method of biotransformation can be applied to solve the above issue. In this study, Aspergillus niger and Eurotium cristatum were used to transform PHZ to PHT in D. indica. Compared with Aspergillus niger, Eurotium cristatum can cause the equimolar conversion of PHZ to PHT. However, Aspergillus niger resulted in the complete degradation of PHZ. In the process of deep fermentation, PHZ in D. indica leaves was gradually biotransformed into PHT, and its content was as high as ~ 12% after fermentation. With the increase of PHT content, the antioxidant and antibacterial activity of Docynia indica leaves increased. By the acute toxicity evaluation, it was confirmed that Docynia indica leaves and Eurotium cristatum fermented leaves were much safer. These results indicate that Eurotium cristatum fermentation has the ability to transform the functional compounds in Docynia indica leaves and increase the antioxidant and antibacterial activity of Docynia indica, thus making it a substitute for PHT and functional tea.


Assuntos
Eurotium , Antibacterianos/farmacologia , Antioxidantes , Aspergillus , Biotransformação , China , Fermentação , Florizina/farmacologia , Folhas de Planta
18.
BMC Anesthesiol ; 21(1): 257, 2021 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-34702181

RESUMO

BACKGROUND: Angiogenesis, the formation of blood vessel from pre-existing ones, plays an important role in many pathophysiological diseases, such as cancer. Opioids are often used in clinic for the management of chronic pain in cancer patients at terminal phases. Here, we investigated and compared the effects and mechanisms of four opioids on angiogenesis. METHODS: We performed angiogenesis assays on human umbilical vein endothelial cells (HUVEC) that represent an in vitro model to assess the toxicity of drugs to endothelium. RESULTS: Morphine and oxycodone at 0.1 µM to 100 µM dose-dependently increased endothelial cell tube formation and proliferation. We observed the same in endothelial cells exposed to fentanyl at 0.1 µM to 10 µM but there was a gradual loss of stimulation by fentanyl at 100 µM and 1000 µM. Morphine and fentanyl reduced endothelial cell apoptosis-induced by serum withdrawal whereas oxycodone did not display anti-apoptotic effect, via decreasing Bax level. Oxycodone at the same concentrations was less potent than morphine and fentanyl. Different from other three opioids, codeine at all tested concentrations did not affect endothelial cell tube formation, proliferation and survival. Mechanism studies demonstrated that opioids acted on endothelial cells via µ-opioid receptor-independent pathway. Although we observed the increased phosphorylation of mitogen-activated protein kinase (MAPK) in cells exposed to morphine, fentanyl and oxycodone, the rescue studies demonstrated that the stimulatory effects of morphine but not fentanyl nor oxycodone were reversed by a specific MAPK inhibitor. CONCLUSION: Our work demonstrates the differential effects and mechanisms of opioids on angiogenesis.


Assuntos
Analgésicos Opioides/farmacologia , Células Endoteliais/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Fentanila/farmacologia , Humanos , Proteínas Quinases Ativadas por Mitógeno/efeitos dos fármacos , Morfina/farmacologia , Oxicodona/farmacologia , Fosforilação , Veias Umbilicais/citologia
19.
Ecotoxicol Environ Saf ; 207: 111295, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32949930

RESUMO

Cadmium (Cd) easily accumulates in tobacco, which endangers public health through Cd exposure from smoking. However, its uptake, translocation, and distribution in tobacco plants during plant development or its response to biochar application are poorly understood. A pot experiment was conducted with tobacco (Yunyan 87) grown in soil severely contaminated with Cd (30 mg kg-1) amended with 0, 1, and 2% (w/w) tobacco stem-derived biochar (BC). The absorption and accumulation of Cd in all parts of the tobacco plants were most active from the rosette stage to the fast growing stage, during which approximately 90% of the Cd deposited in the tobacco leaves occurred, especially in the lower leaves. The Cd concentrations in most plant parts without added biochar decreased significantly by 52.61-78.30% due to the rapid increase in biomass (dilution effect), although the Cd concentration in the lower leaves increased by 48.89% (P < 0.05). However, with the slowdown of the growth rate of tobacco at the maturity stage, the proportion of Cd accumulation in roots and stems without biochar addition increased by 29.01%, resulting in an increased Cd concentration in roots and stems by 63.29-86.80% (P < 0.05). In the different growth stages, the application of biochar reduced the contents of DTPA-extractable and exchangeable Cd in the soil by 5.11-35.14% and 9.20-54.05%, respectively, thus reducing the absorption, accumulation and concentration of Cd in all parts of the tobacco plant. In addition, the inhibitive effect of biochar on the Cd concentration in the leaves was weak at the rosette stage (22.17-53.72%) compared with the other stages (46.14-78.88%), and the degree of inhibition of biochar on the Cd concentration in the middle leaves (37.94-59.24%) was lower than that in the upper and lower leaves (49.04-73.54%) at all developmental stages. However, the long-term remediation effect of biochar on soil Cd contamination needs to be further verified, and the combination of biochar and other technologies should receive additional attention.


Assuntos
Bioacumulação , Cádmio/análise , Carvão Vegetal/química , Nicotiana/crescimento & desenvolvimento , Poluentes do Solo/análise , Biomassa , Cádmio/metabolismo , Folhas de Planta/química , Folhas de Planta/crescimento & desenvolvimento , Raízes de Plantas/química , Raízes de Plantas/crescimento & desenvolvimento , Solo/química , Poluentes do Solo/metabolismo , Nicotiana/química , Nicotiana/metabolismo
20.
J Sci Food Agric ; 101(13): 5645-5651, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33740265

RESUMO

BACKGROUND: Esters are indispensable aroma compounds and contribute significantly to the fruity aromas in fermented condiments. The ester synthesis activity and pathways of Bacillus licheniformis, Candida etchellsii, and Zygosaccharomyces rouxii, isolated from Chinese horse bean chili-paste (CHCP), were investigated. Chemical buffer models containing esterification and alcoholysis systems inoculated with extracellular extracts of these three strains were established. RESULTS: The ester synthesis activity of C. etchellsii was stronger than that of the other two strains. Zygosaccharomyces rouxii could synthesize acetate esters via esterification, whereas the biosynthesis pathways of B. licheniformis and C. etchellsii were esterification and alcoholysis. Esterification exhibited relatively high activity at pH 4, whereas alcoholysis activity improved with an increase in the pH from 4 to 8. Candida etchellsii could synthesize C6 -C8 of acetate esters, and its activity improved with the number of alcohol carbon atoms. These three strains could synthesize C10 -C18 of ethyl esters. Their ethyl ester synthesis activity decreased with the aliphatic acid carbon number. CONCLUSION: Candida etchellsii has the potential to be used in CHCP fermentation to accumulate esters and improve flavor compared with the other two strains. This research is helpful in explaining the mechanism of ester synthesis in fermented condiments. © 2021 Society of Chemical Industry.


Assuntos
Bacillus licheniformis/metabolismo , Candida/metabolismo , Ésteres/metabolismo , Aromatizantes/metabolismo , Saccharomycetales/metabolismo , Vicia faba/microbiologia , China , Condimentos/análise , Condimentos/microbiologia , Esterificação , Ésteres/análise , Fermentação , Alimentos Fermentados/análise , Alimentos Fermentados/microbiologia , Aromatizantes/química , Vicia faba/química , Vicia faba/metabolismo
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