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1.
J Med Virol ; 96(3): e29546, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38516804

RESUMO

Tapasin, a crucial molecular chaperone involved viral antigen processing and presentation, plays an important role in antivirus immunity. However, its impact on T cell differentiation in the context of virus clearance remains unclear. In this study, we employed induced pluripotent stem cells to differentiate into hepatocyte-like cell, which were subsequently inserted to the inverted colloidal crystal scaffolds, thus establishing a hepatocyte organoid (HO). By inoculating hepatitis B virus (HBV) particles in the system, we successfully engineered a robust in vitro HBV infection model for at least 3 weeks. Furthermore, we aimed to explore the effects of lentivirus-mediated short hairpin RNA (shRNA) targeting human Tapasin on the differentiation and antiviral function of CD8+ T cells. Specifically, we transfected dendritic cells (DCs) with Tapasin-shRNA and cocultured with T cells. The results demonstrated that Tapasin-shRNA transfected DCs effectively suppressed T cell proliferation and impeded HBV-specific cytotoxic T lymphocyte responses. Our investigation also revealed the role of mTOR pathway activation in reducing autophagy activity within CD8+ T cells. Expressions of autophagy-related proteins, beclin-1, LC3II/LC3I were decreased and PI3K/AKT/mTOR activity was increased in Tapasin-shRNA group. Collectively, our findings elucidate that shRNA targeting the Tapasin gene within DCs inhibits T cell differentiation by reducing autophagy activity to hamper viral clearance in the HBV-infected HO.


Assuntos
Células Dendríticas , Hepatite B , Proteínas de Membrana Transportadoras , Humanos , Autofagia/genética , Linfócitos T CD8-Positivos/metabolismo , Células Dendríticas/metabolismo , Regulação para Baixo , Hepatite B/metabolismo , Antígenos do Núcleo do Vírus da Hepatite B/genética , Vírus da Hepatite B , Hepatócitos/metabolismo , Células-Tronco Pluripotentes Induzidas , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , RNA Interferente Pequeno/genética , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Organoides/metabolismo , Organoides/virologia
2.
Med Educ Online ; 29(1): 2325182, 2024 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-38465652

RESUMO

Phenomenon: The increase in clinical and teaching workload has brought enormous pressure to clinical teachers. Clinical teachers play an extremely important role in the quality of higher medical education and the cultivation of medical talents. However, few studies have examined the attitudes and practices of clinical teachers regarding the role of teachers in China. This study aimed to investigate clinical teachers' perceptions about their roles and current practices at affiliated hospitals of medical universities in China. Approach: Responses from 312 Chinese clinical teachers were included in the analyses. The data were collected using the questionnaires of perception and practice regarding the role of teachers which consisted of 12 items rated on a 5-point Likert scale, ranging from 1 (strongly disagree) to 5 (strongly agree), and scored by calculating the mean. The data were analyzed using the Statistical Package for Social Sciences, version 22.0 (IBM SPSS Corp). Findings: The mean score of perception of clinical teachers regarding the role of teachers was 4.51 (SD = 0.72), and the mean score of practice was 3.69 (SD = 1.17). Multivariable binary logistic regression model showed that undertaking very few/few clinical teaching workload, 'thinking it is my obligation to carry out teaching work seriously' and 'thinking it is my duty to train medical talents' were not only significant determinants of good perception but also good practice. Additionally, 'thinking hospital attached great importance to clinical teaching' was the significant determinant of good perception. Insights: Chinese clinical teachers demonstrate less positive perception and practice regarding the roles of teacher than clinical teachers in developed countries. Affiliated hospitals of medical universities should hold training sessions regularly and take targeted intervention measures to enhance clinical teachers' perception and practice regarding the roles of teacher.


Assuntos
Educação Médica , Docentes , Humanos , Universidades , Inquéritos e Questionários , Percepção
3.
Water Res ; 254: 121350, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38402752

RESUMO

Redox condition is an important controlling factor for contaminant removal in constructed wetlands; however, the redox-sensitivity of antibiotic removal in wetland sediments under controlled conditions with specific electron acceptors remains unclear. Here, using a 14C radioactive tracer, we explored fate of sulfamethoxazole (SMX) in a wetland sediment slurry under oxic, nitrate-reducing, iron-reducing, and methanogenic conditions. In the sterile treatment, unlike the comparable SMX dissipation from the water phase under four redox conditions, non-extractable residues (NERs) of SMX was highest formed in the sediment under oxic condition, mainly in sequestered and ester/amide-linked forms. Microorganisms markedly promoted SMX transformation in the slurry. The dissipation rate of SMX and its transformation products (TPs) followed the order: oxic ≈ iron-reducing > methanogenic >> nitrate-reducing conditions, being consistent with the dynamics of microbial community in the sediment, where microbial diversity was greater and networks connectivity linking dominant bacteria to SMX transformation were more complex under oxic and iron-reducing conditions. Kinetic modeling indicated that the transformation trend of SMX and its TPs into the endpoint pool NERs depended on the redox conditions. Addition of wetland plant exudates and sediment dissolved organic matter at environmental concentrations affected neither the abiotic nor the biotic transformation of SMX. Overall, the iron-reducing condition was proven the most favorable and eco-friendly for SMX transformation, as it resulted in a high rate of SMX dissipation from water without an increase in toxicity and subsequent formation of significant stable NERs in sediment. Our study comprehensively revealed the abiotic and biotic transformation processes of SMX under controlled redox conditions and demonstrated iron-reducing condition allowing optimal removal of SMX in constructed wetlands.


Assuntos
Sulfametoxazol , Áreas Alagadas , Sulfametoxazol/química , Nitratos , Antibacterianos , Oxirredução , Ferro , Compostos Orgânicos , Água
4.
Int J Radiat Oncol Biol Phys ; 118(1): 218-230, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37586613

RESUMO

PURPOSE: Radiation-induced pulmonary fibrosis (RIPF) is a common side effect of radiation therapy for thoracic tumors without effective prevention and treatment methods at present. The aim of this study was to explore whether glycyrrhetinic acid (GA) has a protective effect on RIPF and the underlying mechanism. METHODS AND MATERIALS: A RIPF mouse model administered GA was used to determine the effect of GA on RIPF. The cocultivation of regulatory T (Treg) cells with mouse lung epithelial-12 cells or mouse embryonic fibroblasts and intervention with GA or transforming growth factor-ß1 (TGF-ß1) inhibitor to block TGF-ß1 was conducted to study the mechanism by which GA alleviates RIPF. Furthermore, injection of Treg cells into GA-treated RIPF mice to upregulate TGF-ß1 levels was performed to verify the roles of TGF-ß1 and Treg cells. RESULTS: GA intervention improved the damage to lung tissue structure and collagen deposition and inhibited Treg cell infiltration, TGF-ß1 levels, epithelial mesenchymal transition (EMT), and myofibroblast (MFB) transformation in mice after irradiation. Treg cell-induced EMT and MFB transformation in vitro were prevented by GA, as well as a TGF-ß1 inhibitor, by decreasing TGF-ß1. Furthermore, reinfusion of Treg cells upregulated TGF-ß1 levels and exacerbated RIPF in GA-treated RIPF mice. CONCLUSIONS: GA can improve RIPF in mice, and the corresponding mechanisms may be related to the inhibition of TGF-ß1 secreted by Treg cells to induce EMT and MFB transformation. Therefore, GA may be a promising therapeutic candidate for the clinical treatment of RIPF.


Assuntos
Ácido Glicirretínico , Lesão Pulmonar , Fibrose Pulmonar , Lesões por Radiação , Animais , Camundongos , Transição Epitelial-Mesenquimal , Fibroblastos/efeitos da radiação , Ácido Glicirretínico/farmacologia , Pulmão/efeitos da radiação , Lesão Pulmonar/patologia , Fibrose Pulmonar/tratamento farmacológico , Fibrose Pulmonar/etiologia , Fibrose Pulmonar/prevenção & controle , Lesões por Radiação/patologia , Linfócitos T Reguladores , Fator de Crescimento Transformador beta1
5.
ChemSusChem ; : e202301634, 2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-37994392

RESUMO

Efficient electrochemical CO2 reduction reaction (ECO2 RR) to multi-electron reductive products remains a great challenge. Herein, molecular engineering of copper phthalocyanines (CuPc) was explored by modifying electron-withdrawing groups (EWGs) (cyano, sulfonate anion) and electron-donating groups (EDGs) (methoxy, amino) to CuPc, then supporting onto carbon paper or carbon cloth by means of droplet coating, loading with carbon nanotubes and coating in polypyrrole (PPy). The results showed that the PPy-coated CuPc effectively catalysed ECO2 RR to CH4 . Interestingly, experimental results and DFT calculations indicated EWGs markedly improved the selectivity of methane for the reason that the introduction of EWGs reduces electron density of catalytic active center, resulting in a positive move to initial reduction potential. Otherwise, the modification of EDGs significantly reduces the selectivity towards methane. This electronic effect and heterogenization of CuPc are facile and effective molecular engineering, benefitting the preparation of electrocatalysts for further reduction of CO2 .

6.
J Biopharm Stat ; : 1-19, 2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37621147

RESUMO

Inverse probability weighting (IPW) is frequently used to reduce or minimize the observed confounding in observational studies. IPW creates a pseudo-sample by weighting each individual by the inverse of the conditional probability of receiving the treatment level that he/she has actually received. In the pseudo-sample there is no variation among the multiple individuals generated by weighting the same individual in the original sample. This would reduce the variability of the data and therefore bias the variance estimate in the target population. Conventional variance estimation methods for IPW estimators generally ignore this underestimation and tend to produce biased estimates of variance. We here propose a more reasonable method that incorporates this source of variability by using parametric bootstrapping based on intra-stratum variability estimates. This approach firstly uses propensity score stratification and intra-stratum standard deviation to approximate the variability among multiple individuals generated based on a single individual whose propensity score falls within the corresponding stratum. The parametric bootstrapping is then used to incorporate the target variability by re-generating outcomes after adding a random error term to the original data. The performance of the proposed method is compared with three existing methods including the naïve model-based variance estimator, the nonparametric bootstrap variance estimator, and the robust variance estimator in the simulation section. An example of patients with sarcopenia is used to illustrate the implementation of the proposed approach. According to the results, the proposed approach has desirable statistical properties and can be easily implemented using the provided R code.

7.
Aging Male ; 26(1): 2235005, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37452735

RESUMO

BACKGROUND: China is one of the countries with the fastest growing prevalence of diabetes mellitus (DM) in the world. This study intended to investigate the association of single nucleotide polymorphisms (SNPs) of FHL5 and LPA with DM risk in the Chinese population. METHODS: This case-control study involved 1,420 Chinese individuals (710 DM patients and 710 controls). Four candidate loci (rs2252816/rs9373985 in FHL5 and rs3124784/rs7765781 in LPA) were successfully screened. The association of SNPs with DM risk was assessed by logistic regression analysis. Differences in clinical characteristics among subjects with different genotypes were analyzed by one-way analysis of variance. RESULTS: Overall analysis indicated that rs3124784 was associated with an increased risk of DM. Stratification analysis showed that rs3124784 significantly increased DM risk in different subgroups (male, non-smoking, non-drinking, and BMI > 24), while rs7765781 increased DM risk only in participants with BMI ≤ 24. Rs2252816 was associated with the course of DM. We also found that rs2252816 GG genotype and rs9373985 GG genotype were linked to the increased cystatin c in DM patients. CONCLUSION: The genetic polymorphisms of LPA may be associated with DM risk in the Chinese population, which will provide useful information for the prevention and diagnosis of DM.


Assuntos
Diabetes Mellitus Tipo 2 , Diabetes Mellitus , Humanos , Masculino , Estudos de Casos e Controles , Polimorfismo de Nucleotídeo Único , Genótipo , China/epidemiologia , Fatores de Transcrição/genética , Proteínas com Domínio LIM/genética
8.
Proc Natl Acad Sci U S A ; 120(20): e2218739120, 2023 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-37155879

RESUMO

Carbon-based nanomaterials (CNMs) have recently been found in humans raising a great concern over their adverse roles in the hosts. However, our knowledge of the in vivo behavior and fate of CNMs, especially their biological processes elicited by the gut microbiota, remains poor. Here, we uncovered the integration of CNMs (single-walled carbon nanotubes and graphene oxide) into the endogenous carbon flow through degradation and fermentation, mediated by the gut microbiota of mice using isotope tracing and gene sequencing. As a newly available carbon source for the gut microbiota, microbial fermentation leads to the incorporation of inorganic carbon from the CNMs into organic butyrate through the pyruvate pathway. Furthermore, the butyrate-producing bacteria are identified to show a preference for the CNMs as their favorable source, and excessive butyrate derived from microbial CNMs fermentation further impacts on the function (proliferation and differentiation) of intestinal stem cells in mouse and intestinal organoid models. Collectively, our results unlock the unknown fermentation processes of CNMs in the gut of hosts and underscore an urgent need for assessing the transformation of CNMs and their health risk via the gut-centric physiological and anatomical pathways.


Assuntos
Microbioma Gastrointestinal , Nanoestruturas , Nanotubos de Carbono , Humanos , Animais , Camundongos , Microbioma Gastrointestinal/fisiologia , Nanotubos de Carbono/efeitos adversos , Fermentação , Butiratos/metabolismo
9.
J Med Virol ; 95(4): e28746, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37185848

RESUMO

Hepatitis B virus (HBV) specific T cell immune response plays a vital role in viral clearance. Dendritic cell derived exosomes (Dexs) can activate T cell immunity effectively. Tapasin (TPN) is involved in antigen processing and specific immune recognition. In the present study, we elucidated that Dexs loading TPN (TPN-Dexs) could enhance CD8+ T cell immune response and inhibit virus replication in HBV transgenic mice. T cell immune response and the ability of inhibiting HBV replication were measured in HBV transgenic mice immunized with TPN-Dexs. Meanwhile, CD8+ T cell autophagy and specific T cell immune responses were measured in vitro and vivo, and the mechanisms probably involved in were explored. Purified TPN-Dexs could be taken up into the cytoplasm of DCs and upregulate CD8+ T cell autophagy to enhance specific T cell immune response. In addition, TPN-Dexs could increase the expression of AKT and decrease the expression of mTOR in CD8+ T cells. Further research confirmed that TPN-Dexs could inhibit virus replication and decrease the expression of HBsAg in the liver of HBV transgenic mice. Nevertheless, those also could elicit mice hepatocytes damage. In conclusion, TPN-Dexs could enhance specific CD8+ T cell immune responses via the AKT/mTOR pathway to regulate the autophagy and exert the antiviral effect in HBV transgenic mice.


Assuntos
Exossomos , Vírus da Hepatite B , Camundongos , Animais , Linfócitos T CD8-Positivos , Proteínas Proto-Oncogênicas c-akt , Camundongos Transgênicos , Serina-Treonina Quinases TOR , Apresentação de Antígeno , Autofagia , Camundongos Endogâmicos C57BL
10.
Int J Radiat Oncol Biol Phys ; 117(1): 237-251, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37054996

RESUMO

PURPOSE: Radiation-induced pulmonary fibrosis (RIPF) is a serious side effect of radiation therapy, but the underlying mechanisms are unknown. B10 cells, as negative B regulatory cells, play important roles in regulating inflammation and autoimmunity. However, the role of B10 cells in RIPF progression is unclear. The aim of this study was to determine the role of B10 cells in aggravating RIPF and the underlying mechanism. METHODS AND MATERIALS: The role of B10 cells in RIPF was studied by constructing mouse models of RIPF and depleting B10 cells with an anti-CD22 antibody. The mechanism of B10 cells in RIPF was further explored through cocultivation of B10 cells and MLE-12 or NIH3T3 cells and administration of an interleukin (IL)-10 antibody to block IL-10. RESULTS: B10 cell numbers increased significantly during the early stage in the RIPF mouse models compared with the controls. In addition, depleting B10 cells with the anti-CD22 antibody attenuated the development of lung fibrosis in mice. Subsequently, we confirmed that B10 cells induced epithelial-mesenchymal transition and the transformation of myofibroblasts via activation of STAT3 signaling in vitro. After blockade of IL-10, it was verified that IL-10 secreted by B10 cells mediates the epithelial-mesenchymal transition of myofibroblasts, thereby promoting RIPF. CONCLUSIONS: Our study uncovers a novel role for IL-10-secreting B10 cells that could be a new target of research for relieving RIPF.


Assuntos
Linfócitos B Reguladores , Fibrose Pulmonar , Animais , Camundongos , Fibrose Pulmonar/etiologia , Interleucina-10 , Células NIH 3T3 , Transição Epitelial-Mesenquimal , Modelos Animais de Doenças
12.
Front Public Health ; 10: 1025221, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36438237

RESUMO

Background: HIV-positive men who have sex with men (MSM) tend to have high syphilis incidence. Our objective is to evaluate the prevalence of syphilis and determine the risk factors of syphilis among HIV-positive MSM. Methods: A cross-sectional study with convenience sampling was performed among HIV-positive MSM in six cities of Guangdong Province from June 2020 to August 2021. Participants completed a survey including social-demographic characteristics, sexual behaviors and self-reported syphilis, chlamydia, gonorrhea, herpes, human papillomavirus statuses after HIV diagnosis. Multivariate logistic regression was used to determine the factors associated with syphilis and sexually transmitted diseases (STD). Results: Among 944 HIV-positive MSM, 141 (14.9, 95% CI: 12.7-17.2%) men had syphilis and 220 (23.3, 95% CI: 20.6-26.0%) men had STD. Multivariate analysis indicated that MSM who met male sexual partners mainly through traditional meeting places (spa or bath house, sauna, foot or body massage parlor) in the last 6 months [adjusted Odds Ratio (aOR) = 2.91, 95% CI: 1.09-7.79], and who were diagnosed with herps after the HIV diagnosis (aOR = 3.79, 95% CI: 1.16-12.39) were more likely to have syphilis. In addition, MSM who met male sexual partners mainly through traditional meeting places in the last 6 month (aOR = 2.55, 95% CI: 1.01-6.42), and who had more than one male sexual partner in the last 6 months (aOR = 1.88, 95% CI: 1.17-3.02) were more likely to have STD. Conclusions: The prevalence of syphilis and other STDs is relatively high among HIV-positive MSM in southern China. Routine syphilis screening as a part of HIV monitoring among HIV-positive MSM will have important epidemiological significance for the management of infected patients, and can help reduce the spread of syphilis.


Assuntos
Infecções por HIV , Minorias Sexuais e de Gênero , Infecções Sexualmente Transmissíveis , Sífilis , Humanos , Masculino , Feminino , Sífilis/epidemiologia , Homossexualidade Masculina , Prevalência , Estudos Transversais , Infecções por HIV/epidemiologia , Infecções Sexualmente Transmissíveis/epidemiologia , Fatores de Risco
13.
J Gastrointest Oncol ; 13(5): 2472-2484, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36388672

RESUMO

Background: Hepatocellular carcinoma (HCC) is a malignant cancer with rapid progression, vascular invasion, a high recurrence rate and poor prognosis, so it is necessary to take early measures to halt this process. Accumulating evidence indicates that collagen XV (translated by Col15a1) is a basement membrane molecule related to tumour metastasis in several organs. However, the potential function of collagen XV in the liver associated with HCC remains to be further elucidated. Methods: Col15a1 was overexpressed in HepG2 and HCCLM3 cells. CCK8 and colony formation assays were used to assess the capacity of cell proliferation, and Transwell and wound healing assays were utilized to measure cell migration. Western blotting and real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) quantified the protein and mRNA expression levels of genes related to the epithelial-mesenchymal transition (EMT). Then, the effect of collagen XV on tumour metastasis was confirmed in vivo. Finally, we inhibited discoidin domain receptor 1 (DDR1) via DDR1-IN-1 to explore whether the collagen XV interacted with DDR1 to regulate EMT. Results: Patients of HCC with higher expression of Col15a1 showed better survival than patients with low expression. Overexpression of collagen XV in HepG2 and HCCLM3 cells suppressed cell proliferation and migration in vitro and inhibited pulmonary and liver metastasis in vivo. In addition, collagen XV downregulated the DDR1 and transcription factor (Snail, Slug), regulated the EMT markers (Vimentin, E-cadherin, N-cadherin, and MMP9). Furthermore, inhibition of the DDR1 receptor by DDR1-IN-1 suppressed the gene promoting the EMT. Conclusions: Collagen XV functioned as a metastasis inhibitor in HCC by regulating the DDR1-Snail/Slug axis to regulate EMT.

14.
Front Cell Infect Microbiol ; 12: 967584, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36389162

RESUMO

Spinal infection is a rarely occurred pathology, whose diagnosis remains a major challenge due to the low sensitivity of culturing techniques. Metagenomic next-generation sequencing (mNGS) is a novel approach to identify the pathogenic organisms in infectious diseases. In this study, mNGS technology was adopted for pathogenic detection in spinal infection from the tissue and pus samples. Additionally, the diagnostic performance of mNGS for spinal infection was evaluated, by comparing it with that of the conventional microbial culture, with the histopathological results as the gold standard. Overall, 56 samples from 38 patients were enrolled for mNGS testing, and 69 samples were included for microbial culture. 30 patients (78.95%) were identified to be positive by the mNGS method, which was higher than that of microbial culture (17, 44.74%). The sensitivity and specificity of mNGS with pus samples were 84.2% and 100.0%, respectively, which outperformed those of microbial culture (42.1% and 100.0%). The pathogen identification results were applied to medication guidance, and all 38 patients experienced favorable outcomes at three months, followed-up post-treatment, without any adverse effects. These findings proved that mNGS was superior to microbial culture in pathogenic identification of the spinal infection, thereby showing great promise in guiding drug administration and improving clinical outcomes.


Assuntos
Metagenoma , Metagenômica , Humanos , Metagenômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Sensibilidade e Especificidade , Supuração
15.
ChemSusChem ; 15(23): e202201455, 2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36163546

RESUMO

Immobilizing cobalt phthalocyanine (CoPc) onto the electrode surface is a significant approach to performing efficient electrochemical CO2 reduction reaction (ECO2 RR). Herein, sulfylphenoxy decorated CoPc cross-linked polypyrrole is prepared by in situ polymerization on the surface of carbon cloth. The synthesized N-rich catalyst exhibits above 95 % Faradaic efficiency toward CO (FECO ) at -0.9 V versus reversible hydrogen electrode (RHE) at least for 10 h in aqueous solution and even enables direct electrolysis at low CO2 concentrations, being potential for coupling ECO2 RR with CO2 capture. This facile in situ polymerization strategy would pave the way for developing efficient and practical electrocatalysis for ECO2 RR.


Assuntos
Polímeros , Pirróis , Dióxido de Carbono , Indóis
16.
Angew Chem Int Ed Engl ; 61(44): e202205301, 2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-35866885

RESUMO

The electrocatalytic CO2 reduction reaction (ECO2 RR) is one promising method for storing intermittent clean energy in chemical bonds and producing fuels. Among various kinds of catalysts for ECO2 RR, molecular metal complexes with well-defined structures are convenient for studies of their rational design, structure-reactivity relationships, and mechanisms. In this Review, we summarize the molecular engineering of several N-based metal complexes including Re/Mn bipyridine compounds and metal macrocycles, concluding with general modification strategies to devise novel molecular catalysts with high intrinsic activity. Through physical adsorption, covalent linking, and formation of a periodic backbone, these active molecules can be heterogenized into immobilized catalysts with more practical prospects. Finally, significant challenges and opportunities based on molecular catalysts are discussed.

17.
Eur Radiol ; 32(9): 6080-6089, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35364716

RESUMO

OBJECTIVES: We aimed to investigate the associations between carotid vulnerable plaque features coexisting with cerebral small vessel diseases (CSVDs) and acute ischemic stroke (AIS) and, furthermore, to determine whether coexisting diseases had a stronger association with AIS than a single disease. METHODS: Patients with cerebrovascular symptoms and carotid plaque were recruited from the cross-sectional, multicenter CARE-II study. The population was divided into two groups (AIS and transient ischemic stroke (TIA)). MRI features of carotid plaques (including luminal stenosis and plaque vulnerabilities) and CSVDs (such as white matter hyperintensities (WMHs) and lacunes) were evaluated. Coexisting diseases were defined as the presence of at least one carotid plaque features and one or more CSVDs feature. Multivariate logistic regression was performed to examine the associations between coexisting diseases and AIS. RESULTS: Of the recruited 634 patients (mean age: 59.1 ± 11.3 years; 429 males), 312 (49.2%) patients had AIS. These subjects had a higher prevalence of carotid vulnerable plaques, lacunes, and moderate-to-severe WMHs (a total Fazekas score of 3-6) than those with TIA (42.6% vs. 29.5%, 59.6% vs. 26.4%, 69.9% vs. 60.6%, respectively, all p < 0.05). Multivariate analysis revealed that carotid plaque features coexisting with lacunes or moderate-to-severe WMHs had a stronger association with AIS compared to carotid lesions alone (all p < 0.05) (i.e., vulnerable plaque coexisting with lacunes vs. vulnerable plaque alone, adjusted odds ratio: 3.67 vs. 1.62). CONCLUSIONS: Carotid vulnerable plaque features coexisting with CSVDs, particularly lacunes, had a stronger association with AIS compared to carotid lesions alone in a large, symptomatic, cohort. TRIAL REGISTRATION: Clinical trial registration URL: http://www. CLINICALTRIALS: gov , unique identifier: NCT02017756 KEY POINTS: • Carotid vulnerable plaque features coexisting with cerebral small vessel diseases, such as lacunes, had a stronger association with acute ischemic stroke compared to single diseases in symptomatic patients. • A comprehensive assessment of coexisting cerebrovascular diseases may help stratify the risk of acute ischemic stroke.


Assuntos
Aterosclerose , Estenose das Carótidas , Doenças de Pequenos Vasos Cerebrais , Ataque Isquêmico Transitório , AVC Isquêmico , Placa Aterosclerótica , Acidente Vascular Cerebral , Idoso , Estenose das Carótidas/complicações , Estenose das Carótidas/diagnóstico por imagem , Estenose das Carótidas/epidemiologia , Doenças de Pequenos Vasos Cerebrais/complicações , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Doenças de Pequenos Vasos Cerebrais/epidemiologia , China/epidemiologia , Estudos Transversais , Humanos , Ataque Isquêmico Transitório/complicações , Ataque Isquêmico Transitório/epidemiologia , AVC Isquêmico/complicações , AVC Isquêmico/diagnóstico por imagem , AVC Isquêmico/epidemiologia , Masculino , Pessoa de Meia-Idade , Placa Aterosclerótica/complicações , Placa Aterosclerótica/diagnóstico por imagem , Fatores de Risco , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/epidemiologia
18.
Angew Chem Int Ed Engl ; 61(27): e202200751, 2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35441773

RESUMO

A triblock amphiphilic polymer derived from the copolymerization of CO2 and epoxides containing a bipyridine rhenium complex in its backbone is shown to effectively catalyze the visible-light-driven reduction of CO2 to CO. This polymer provides uniformly spherical micelles in aqueous solution, where the metal catalyst is sequestered in the hydrophobic portion of the nanostructured micelle. CO2 to CO reduction occurs in an efficient visible-light-driven process in aqueous media with turnover numbers up to 110 (>99 % selectivity) in the absence of a photosensitizer, which is a 37-fold enhancement over the corresponding molecular rhenium catalyst in organic solvent. Notably, the amphiphilic polycarbonate micelle rhenium catalyst suppresses H2 generation, presumably by preventing deactivation of the active catalytic center by water.

19.
Phytochem Anal ; 33(4): 635-643, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35229907

RESUMO

INTRODUCTION: The comprehensive component characterisation of Chinese herbal medicine is the premise of effectively driving the discovery of pharmacodynamic substances or new drugs in recent years. OBJECTIVE: To use the high-throughput liquid chromatography-mass spectrometry (LC-MS) approach to systematically characterise phytochemical compounds from four hawthorn leaf extracts, along with evaluating their classification. METHODS: In the present study, the compounds from 50% ethanol extract, macro porous resin extract, ethyl acetate extract and standard decoction of hawthorn leaves were completely analysed by ultrahigh-performance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry (UPLC-Q-TOF-MS). RESULTS: Eight-nine compounds were putatively identified by comparison with secondary MS data and available references. Of these compounds identified, 56 compounds were found for the first time in hawthorn leaves, which was somewhat inconsistent with the findings of other studies. It could be inferred that falconoid, organic acids and nitrogenous compounds were the most abundant in 50% ethanol extract and standard decoction extract, which were considered as better choices for extracting hawthorn leaves. CONCLUSIONS: This work developed a simple, accurate and rapid method for the compound identification of hawthorn leaves, which laid the basis for further discovering pharmacodynamic material basis or new drugs from hawthorn leaves.


Assuntos
Crataegus , Medicamentos de Ervas Chinesas , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Crataegus/química , Etanol , Extratos Vegetais/química , Espectrometria de Massas em Tandem
20.
Chemosphere ; 295: 133867, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35143860

RESUMO

Electrolysis had proven to be useful for the enhanced performance in constructed wetlands (CWs). While at cold temperature, the nitrate removal pathways, plant physiological characteristics and microbial community structure in electrolysis-assisted CWs were unclear. Therefore, the purification performance of three electrolysis-assisted horizontal subsurface-flow constructed wetlands (E-HSCWs) with different anodes and a control system in cold seasons were evaluated in this study. E-HSCWs showed a 2.02-83.21% increase of total nitrogen (TN) removal when compared to control, and the gaps were enlarged with increasing C/N (chemical oxygen demand/total nitrogen, COD/TN) ratios. Nitrite accumulation in E-HSCWs presented a first increase then went down trend with increasing C/N ratios, compared to a steady increase in control system. The optimum C/N ratio was 8 in E-HSCWs for both TN and COD removal. Moreover, Ti|IrO2-Ta2O5 (Ti) anode showed the highest potential for TN and COD removal. Less root weight, shorter root length and reduced TN and total phosphorus (TP) contents in roots were observed in wetland plants (Iris sibirica) of E-HSCWs. In E-HSCWs with Fe and C anodes, the nitrate removal was mainly accomplished by autotrophic denitrifier Hydrogenophaga. While in E-HSCWs with Ti anode, the synergistic effect of autotrophic denitrifier Hydrogenophaga and heterotrophic denitrifiers Acidovorax, Simplicispira, Zoogloea accounted for the nitrate removal. These results showed that E-HSCWs at proper C/N ratio of 8 would be promising for nitrate removal at cold temperature.


Assuntos
Nitratos , Áreas Alagadas , Temperatura Baixa , Desnitrificação , Eletrodos , Eletrólise , Nitrogênio/química , Eliminação de Resíduos Líquidos/métodos
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