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The elevation of the low-temperature oxidation activity for Pt/CeO2 catalysts is challenging to meet the increasingly stringent requirements for effectively eliminating carbon monoxide (CO) from automobile exhaust. Although reducing activation is a facile strategy for boosting reactivity, past research has mainly concentrated on applying H2 as the reductant, ignoring the reduction capabilities of CO itself, a prevalent component of automobile exhaust. Herein, atomically dispersed Pt/CeO2 was fabricated and activated by CO, which could lower the 90% conversion temperature (T90) by 256 °C and achieve a 20-fold higher CO consumption rate at 200 °C. The activated Pt/CeO2 catalysts showed exceptional catalytic oxidation activity and robust hydrothermal stability under the simulated working conditions for gasoline or diesel exhausts. Characterization results illustrated that the CO activation triggered the formation of a large portion of Pt0 terrace sites, acting as inherent active sites for CO oxidation. Besides, CO activation weakened the Pt-O-Ce bond strength to generate a surface oxygen vacancy (Vo). It served as the oxygen reservoir to store the dissociated oxygen and convert it into active dioxygen intermediates. Conversely, H2 activation failed to stimulate Vo, but triggered a deactivating transformation of the Pt nanocluster into inactive PtxOy in the presence of oxygen. The present work offers coherent insight into the upsurging effect of CO activation on Pt/CeO2, aiming to set up a valuable avenue in elevating the efficiency of eliminating CO, C3H6, and NH3 from automobile exhaust.
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Monóxido de Carbono , Oxirredução , Catálise , Monóxido de Carbono/química , Emissões de Veículos , Platina/química , Cério/químicaRESUMO
Florpyrauxifen-benzyl is a novel herbicide used to control weeds in paddy fields. To clarify and evaluate its hydrolytic behavior and safety in water environments, its hydrolytic characteristics were investigated under varying temperatures, pH values, initial mass concentrations and water types, as well as the effects of 40 environmental factors such as microplastics (MPs) and disposable face masks (DFMs). Meanwhile, hydrolytic products were identified by UPLC-QTOF-MS/MS, and its hydrolytic pathways were proposed. The effects of MPs and DFMs on hydrolytic products and pathways were also investigated. The results showed that hydrolysis of florpyrauxifen-benzyl was a spontaneous process driven by endothermic, base catalysis and activation entropy increase and conformed to the first-order kinetics. The temperature had an obvious effect on hydrolysis rate under alkaline condition, the hydrolysis reaction conformed to Arrhenius formula, and activation enthalpy, activation entropy, and Gibbs free energy were negatively correlated with temperature. Most of environmental factors promoted hydrolysis of florpyrauxifen-benzyl, especially the cetyltrimethyl ammonium bromide (CTAB). The hydrolysis mechanism was ester hydrolysis reaction with a main product of florpyrauxifen. The MPs and DFMs did not affect the hydrolytic mechanisms but the hydrolysis rate. The results are crucial for illustrating and assessing the environmental fate and risks of florpyrauxifen-benzyl.
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Herbicidas , Água , Espectrometria de Massas em Tandem , Cinética , Plásticos , HidróliseRESUMO
As an enrichment strategy supplemented by the diagnostic framework of subjective cognitive decline (SCD), SCD plus identifies features that may increase the likelihood of including future-Alzheimer's disease (AD) patients. This study aimed to identify the shared and distinct atrophy patterns between patients specified by SCD plus and amnestic mild cognitive impairment (aMCI, a prodromal stage of AD) and to investigate the extent that automated brain magnetic resonance imaging (MRI) volumetry can differentiate patients with SCD from normal control (NC) participants and patients with aMCI. We acquired structural MRI brain scans from 44 patients with aMCI, 40 patients with SCD (who met the major criteria of SCD plus), and 48 NC participants. Automatic brain segmentation was performed to quantify the volumetric measures of cognitive-relevant areas. These volumetric measures were compared across the 3 groups with analysis of variance. In addition, we performed support vector machine analyses using volumetric measures of single regions or multiple regions to further evaluate the sensitivity of automated brain volumetry in differentiating a specific group from another. The atrophy patterns in patients with aMCI and SCD were similar. Using the regional volumetric measures, we achieved high performance in differentiating aMCI and SCD from NCs (average classification accuracy [ACC] > 90%). However, the performance was not ideal when differentiating aMCI from SCD (ACC < 63%). In conclusion, patients with SCD specified by SCD plus presented similar atrophy patterns as patients with aMCI, which was distinguishable from NC participants. Future studies should aim to associate the atrophy patterns of SCD with possible conversion to aMCI or AD in a longitudinal design.
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Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/diagnóstico , Encéfalo/patologia , Imageamento por Ressonância Magnética/métodos , Idoso , Disfunção Cognitiva/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de NeoplasiasRESUMO
The attachment of monocytes to human brain microvascular endothelial cells (HBMVEs) caused by oxidized low-density lipoprotein (ox-LDL) is associated with an early event and the pathological progression of cerebrovascular diseases. Oxytocin (OT) is a human peptide hormone that is traditionally used as a medication to facilitate childbirth. However, little information is available regarding the physiological function of OT in brain endothelial dysfunction. In the present study, our results indicate that the oxytocin receptor (OTR) was expressed in human brain microvascular endothelial cells (HBMVEs) and was upregulated in response to ox-LDL in a concentration-dependent manner. Notably, OT significantly suppressed ox-LDL-induced attachment of THP-1 monocytes to HBMVEs. Furthermore, we found that OT reduced the expression of adhesion molecules, such as VCAM-1 and E-selectin. Interestingly, it was shown that OT could restore ox-LDL-induced reduction of KLF4 in HBMVEs. Importantly, knockdown of KLF4 abolished the inhibitory effects of OT on ox-LDL-induced expressions of VCAM-1 and E-selectin as well as the adhesion of human monocytic THP-1 cells to endothelial HBMVEs. Mechanistically, we found that the stimulatory effects of OT on KLF4 expression are mediated by the MEK5/MEF2A pathway.
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Encéfalo/irrigação sanguínea , Adesão Celular/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Lipoproteínas LDL/farmacologia , Microvasos/efeitos dos fármacos , Monócitos/efeitos dos fármacos , Ocitocina/farmacologia , Linhagem Celular Tumoral , Técnicas de Cocultura , Relação Dose-Resposta a Droga , Selectina E/genética , Selectina E/metabolismo , Células Endoteliais/metabolismo , Humanos , Fator 4 Semelhante a Kruppel , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , MAP Quinase Quinase 5/genética , MAP Quinase Quinase 5/metabolismo , Fatores de Transcrição MEF2/genética , Fatores de Transcrição MEF2/metabolismo , Microvasos/metabolismo , Monócitos/metabolismo , Interferência de RNA , Receptores de Ocitocina/agonistas , Receptores de Ocitocina/genética , Receptores de Ocitocina/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transfecção , Molécula 1 de Adesão de Célula Vascular/genética , Molécula 1 de Adesão de Célula Vascular/metabolismoRESUMO
T cell Ig and ITIM domain (TIGIT) is a newly identified inhibitory receptor expressed on T and natural killer (NK) cells. Cytokine-induced killer (CIK) cells express CD3 and CD56 molecules, and share functional properties with both NK and T cells. However, it remains unknown whether TIGIT is expressed in CIK cells. Here, we show that TIGIT is expressed by CIK cells and interacts with CD155. By blocking TIGIT using an anti-TIGIT functional antibody, we demonstrate that CIK cells display increased proliferation; higher cytotoxic targeting of tumor cells expressing CD155; and higher expression of interferon-γ (IFN-γ), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α). Furthermore, increases in IFN-γ and cytotoxicity by blockade of TIGIT were reduced by blocking DNAX accessory molecule-1 (DNAM-1) signaling, implying that TIGIT exerts immunosuppressive effects by competing with DNAM-1 for the same ligand, CD155. Our results provide evidence that blockade of TIGIT may be a novel strategy to improve the cytotoxic activity of CIK cells.
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Células Matadoras Induzidas por Citocinas/imunologia , Citotoxicidade Imunológica , Receptores Imunológicos/fisiologia , Receptores Virais/fisiologia , Antígenos de Diferenciação de Linfócitos T/fisiologia , Linhagem Celular Tumoral , Humanos , Transdução de Sinais/fisiologiaRESUMO
Transcription plays an important role in both HIV-1 gene expression and replication and mandates complicated but coordinated interactions between the host and virus. Our previous studies have shown that an HIV-1 Tat-interacting protein of 110 kDa, Tip110, binds to and enhances Tat function in Tat-mediated HIV-1 gene transcription and replication (Liu, Y., Li, J., Kim, B. O., Pace, B. S., and He, J. J. (2002) HIV-1 Tat protein-mediated transactivation of the HIV-1 long terminal repeat promoter is potentiated by a novel nuclear Tat-interacting protein of 110 kDa, Tip110. J. Biol. Chem. 277, 23854-23863). However, the underlying molecular mechanisms by which this takes place were not understood. In this study, we demonstrated that Tip110 bound to unphosphorylated RNA polymerase II (RNAPII) in a direct and specific manner. In addition, we detected Tip110 at the HIV-1 long terminal repeat (LTR) promoter and found that Tip110 expression was associated with increased phosphorylation of serine 2 of the heptapeptide repeats within the RNAPII C-terminal domain and increased recruitment of positive transcription elongation factor b to the LTR promoter. Consistent with these findings, we showed that Tip110 interaction with Tat directly enhanced transcription elongation of the LTR promoter. Taken together, these findings have provided additional and mechanistic evidence to support Tip110 function in HIV-1 transcription.
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Antígenos de Neoplasias/metabolismo , Regulação Viral da Expressão Gênica , Repetição Terminal Longa de HIV , HIV-1/metabolismo , Regiões Promotoras Genéticas , RNA Polimerase II/metabolismo , Proteínas de Ligação a RNA/metabolismo , Elongação da Transcrição Genética , Antígenos de Neoplasias/genética , Linhagem Celular , HIV-1/genética , Humanos , Fosforilação/genética , Ligação Proteica , RNA Polimerase II/genética , Proteínas de Ligação a RNA/genética , Produtos do Gene tat do Vírus da Imunodeficiência Humana/genética , Produtos do Gene tat do Vírus da Imunodeficiência Humana/metabolismoRESUMO
This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the Editor-in-Chief. The article has been submitted without the knowledge of the three co-authors whose emails were invented and those three co-authors were not involved in this submission. As such this article represents a severe abuse of the scientific publishing system. The scientific community takes a very strong view on this matter and apologies are offered to readers of the journal that this was not detected during the submission process.
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Background: Vascular cognitive impairment (VCI) is a major cause of cognitive impairment in the elderly and a co-factor in the development and progression of most neurodegenerative diseases. With the continuing development of neuroimaging, multiple markers can be combined to provide richer biological information, but little is known about their diagnostic value in VCI. Methods: A total of 83 subjects participated in our study, including 32 patients with vascular cognitive impairment with no dementia (VCIND), 21 patients with vascular dementia (VD), and 30 normal controls (NC). We utilized resting-state quantitative electroencephalography (qEEG) power spectra, structural magnetic resonance imaging (sMRI) for feature screening, and combined them with support vector machines to predict VCI patients at different disease stages. Results: The classification performance of sMRI outperformed qEEG when distinguishing VD from NC (AUC of 0.90 vs. 0,82), and sMRI also outperformed qEEG when distinguishing VD from VCIND (AUC of 0.8 vs. 0,0.64), but both underperformed when distinguishing VCIND from NC (AUC of 0.58 vs. 0.56). In contrast, the joint model based on qEEG and sMRI features showed relatively good classification accuracy (AUC of 0.72) to discriminate VCIND from NC, higher than that of either qEEG or sMRI alone. Conclusion: Patients at varying stages of VCI exhibit diverse levels of brain structure and neurophysiological abnormalities. EEG serves as an affordable and convenient diagnostic means to differentiate between different VCI stages. A machine learning model that utilizes EEG and sMRI as composite markers is highly valuable in distinguishing diverse VCI stages and in individually tailoring the diagnosis.
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BACKGROUND: Human society has entered the age of artificial intelligence, medical practice and medical education are undergoing profound changes. Artificial intelligence (AI) is now applied in many industries, particularly in healthcare and medical education, where it deeply intersects. The purpose of this paper is to overview the current situation and problems of "AI+medicine/medical" education and to provide our own perspective on the current predicament. METHODS: We searched PubMed, Embase, Cochrane and CNKI databases to assess the literature on AI+medical/medical education from 2017 to July 2022. The main inclusion criteria include literature describing the current situation or predicament of "AI+medical/medical education". RESULTS: Studies have shown that the current application of AI in medical education is focused on clinical specialty training and continuing education, with the main application areas being radiology, diagnostics, surgery, cardiology, and dentistry. The main role is to assist physicians to improve their efficiency and accuracy. In addition, the field of combining AI with medicine/medical education is steadily expanding, and the most urgent need is for policy makers, experts in the medical field, AI and education, and experts in other fields to come together to reach consensus on ethical issues and develop regulatory standards. Our study also found that most medical students are positive about adding AI-related courses to the existing medical curriculum. Finally, the quality of research on "AI+medical/medical education" is poor. CONCLUSION: In the context of the COVID-19 pandemic, our study provides an innovative systematic review of the latest "AI+medicine/medical curriculum". Since the AI+medicine curriculum is not yet regulated, we have made some suggestions.
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The reactive oxygen species (ROS) involved photocatalytic ozonation of gaseous n-hexane to heterocyclic compounds has been recently reported. However, whether such heterocyclization reaction happens on other alkanes and what is the contributing mechanism of ROS to the heterocyclic compound formation are still unclear. In present study, photocatalytic ozonation of three n-hexane's isomers (i.e. 2-methypentane, 3-methylpentane and 2,3-dimethylbutane) on Cu2O-CuO/TiO2-foam ceramic was investigated. Within reaction period, 2-methylpentane and 3-methylpentane not only showed higher average degradation efficiency than 2,3-dimethylbutane, but also separately converted to interfacial heterocyclic compounds of 5,5-dimethyldihydro-2(3H)-furanone and 4,5-dimethyl-4,5-dihydro-2(3H)-furanone. Enough reaction time, optimum experimental atmosphere and shorter light wavelength benefited the formation of heterocyclization products. None of O3, 1O2, electron and hole directly contributed to the heterocyclic compound formation. While â¢O2- dominated the production of the heterocyclic compound under the dry reaction atmosphere and â¢OH showed more important role than â¢O2- in the heterocyclic compound formation under the moist reaction atmosphere. Theoretical calculation confirmed that â¢OH or â¢O2- induced heterocyclization reaction of alkane was exothermic, while the former reaction released 0.47 eV higher energy than the later reaction. The findings provide a comprehensive understanding of contributing roles of ROS in heterocyclization reaction of alkanes, and are helpful for effective elimination of industrial alkanes by advanced oxidation methods.
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Hexanos , Ozônio , Espécies Reativas de Oxigênio , Alcanos , CatáliseRESUMO
Bioaerosol can cause the spread of disease, and therefore, capture and inactivation of bioaerosols is desirable. However, filtration systems can easily become blocked, and are often unable to inactivate the bioaerosol once it is captured. Herein, we reported a bioinspired artificial spider silk (ASS) photocatalyst, consisting of a periodic spindle structure of TiO2 on nylon fiber that can efficiently capture and concentrate airborne bacteria, followed by photocatalytic inactivation in situ, without a power-supply exhaust system. The ASS photocatalyst exhibits a higher capture capacity than the nylon fiber substrate and a photocatalytic inactivation efficiency of 99.99% obtained under 4 h irradiation. We found that the capture capacity of the ASS photocatalyst can be mainly attributed to the synergistic effects of hydrophilicity, Laplace pressure differences caused by the size of the spindle knots and surface energy gradients induced by surface roughness. The bacteria captured by the ASS photocatalyst are inactivated by photocatalysis within droplets or at the air/photocatalyst interfaces. This strategy paves the way for constructing materials for bioaerosol purification.
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Nylons , Seda , Aerossóis , Bactérias , Seda/químicaRESUMO
Porous fibers as excellent carriers can be used to prepare photoluminescence materials. Herein, cellulose nanocrystals (CNCs) were derived from microcrystalline cellulose (MCC) by sulfuric acid hydrolysis. After CNCs were squeezed into a coagulating bath containing silicon precursors obtained by the hydrolysis of tetraethyl orthosilicate, porous cellulose fibers were constructed through self-assembly and then incorporated with graphene carbon quantum dots (GQDs) to prepare porous photoluminescence cellulose fibers. The silicon precursor amount, self-assembly time, and corrosion time were optimized. In addition, the morphology, structure and optical properties of the products were investigated. These results showed that as-prepared porous cellulose fibers with mesopores presented loose and porous mesh. Interestingly, the porous photoluminescence cellulose fibers exhibited blue fluorescence, and the maximum emission peak appeared at 430 nm under the excitation wavelength of 350 nm. Furthermore, the relative fluorescence intensity of the porous photoluminescence cellulose fibers was significantly enhanced compared with nonporous photoluminescence cellulose fibers. This work provided a new method to prepare environmentally and stably photoluminescence fibers, which had potential applications in anti-counterfeit packaging and smart packaging.
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Objective: This study explored the structural imaging changes in patients with subcortical ischemic vascular disease (SIVD)-vascular cognitive impairment no dementia (VCIND) and the correlation between the changes in gray matter volume and the field of cognitive impairment to provide new targets for early diagnosis and treatment. Methods: Our study included 15 patients with SIVD-normal cognitive impairment (SIVD-NCI), 63 with SIVD-VCIND, 26 with SIVD-vascular dementia (SIVD-VD), and 14 normal controls (NC). T1-weighted images of all participants were collected, and DPABI and SPM12 software were used to process the gray matter of the four groups based on voxels. Fisher's exact test, one-way ANOVA and Kruskal-Wallis H test were used to evaluate all clinical and demographic data and compare the characteristics of diencephalic gray matter atrophy in each group. Finally, the region of interest (ROI) of the SIVD-VCIND was extracted, and Pearson correlation analysis was performed between the ROI and the results of the neuropsychological scale. Results: Compared to the NC, changes in gray matter atrophy were observed in the bilateral orbitofrontal gyrus, right middle temporal gyrus, superior temporal gyrus, and precuneus in the SIVD-VCIND. Gray matter atrophy was observed in the left cerebellar region 6, cerebellar crural region 1, bilateral thalamus, right precuneus, and calcarine in the SIVD-VD. Compared with the SIVD-VCIND, gray matter atrophy changes were observed in the bilateral thalamus in the SIVD-VD (p < 0.05, family-wise error corrected). In the SIVD-VCIND, the total gray matter volume, bilateral medial orbital superior frontal gyrus, right superior temporal gyrus, middle temporal gyrus, and precuneus were positively correlated with Boston Naming Test score, whereas the total gray matter volume, right superior temporal gyrus, and middle temporal gyrus were positively correlated with overall cognition. Conclusion: Structural magnetic resonance imaging can detect extensive and subtle structural changes in the gray matter of patients with SIVD-VCIND and SIVD-VD, providing valuable evidences to explain the pathogenesis of subcortical vascular cognitive impairment and contributing to the early diagnosis of SIVD-VCIND and early warning of SIVD-VD.
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BACKGROUND: Alcohol dependence has become a major problem that poses a serious threat to public health. Long-term heavy alcohol consumption can lead to brain functional disorders. This study aimed to investigate the relationship of the severity of cerebral white matter lesions (WMLs), serum neurofilament light (NfL) and inflammatory factors, tumour necrosis factor alpha (TNF-α) and Interleukin-1ß (IL-1ß), with the cognitive function of patients with alcohol dependence. METHODS: A total of 118 patients were enrolled in this prospective study, and divided into alcohol-dependent and non-alcohol-dependent groups. The severity of WMLs was assessed using the Fazekas scale based on magnetic resonance imaging analysis. The expression levels of NfL, TNF-α and IL-1ß in the serum of the subjects were measured by enzyme-linked immunosorbent assay. The cognitive function and psychological status of the patients were assessed using the Minimum Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), Hamilton Depression Rating Scale (HAMD) and Hamilton Anxiety Rating Scale (HAMA). The severity of WMLs and the expression levels of serum NfL, TNF-α and IL-1ß in alcohol-dependent patients were analysed for their influence on cognitive function. This clinical trial was approved by China Clinical Trials Registry, and the trial number is ChiCTR2200066057 (http://www.chictr.org.cn/searchproj.aspx). RESULTS: The score of Fazekas scale was higher, and the MMSE score and MoCA score were lower in the alcohol-dependent group than those in the non-alcohol-dependent group. Moreover, the Fazekas score of the alcohol-dependent group was negatively correlated with the MMSE and MoCA scores. The serum NfL, TNF-α and IL-1ß levels were higher in the alcohol-dependent group than in the non-alcohol-dependent group, and the serum NfL, TNF-α and IL-1ß levels in the alcohol-dependent group were negatively correlated with the MMSE and MoCA scores. CONCLUSION: Alcohol-dependent patients have more severe cerebral WMLs and significant cognitive impairment, particularly in visuospatial and executive functions, attention, calculation, abstraction, delayed recall and orientation. Serum NfL, TNF-α and IL-1ß may be used as biomarkers to assess alcohol related cognitive decline.
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Objective: This study was designed to explore the characteristics of retinal microangiopathy in patients with cerebral small vessel disease (CSVD) and clarify its interaction with the risk factors for CSVD. Methods: Sixty patients with CSVD and 15 healthy individuals were enrolled. Demographic data, risk factors, and medical history were recorded, and magnetic resonance imaging was performed to detect and analyze the characteristics of retinal microangiopathy in the two groups. The interaction among retinal microangiopathy, vascular risk factors, and total imaging load of CSVD was compared. Results: (1) Hypertension, standard deviation of systolic blood pressure (SBPSD), standard deviation of blood glucose (SDBG), and atherogenic index of plasma (AIP) were independent vascular risk factors for CSVD. (2) Statistically significant differences in hypertension, SBPSD, SDBG, and AIP were observed between the two groups in terms of the total imaging burden of CSVD (p < 0.05). (3) Multivariate logistic linear regression showed that CSVD was associated with a wider central retinal vein equivalent (CRVE) (p = 0.015), a smaller arteriole-to-venule ratio (AVR) (p = 0.001), and a higher incidence of vessel tortuosity (p = 0.027). (4) When the total imaging burden of CSVD ranges from 0 to 4 points, the CRVE is larger, the AVR is smaller, and the incidence of vascular tortuosity is higher, with a statistically significant difference (p < 0.05). (5) The characteristics of retinal microangiopathy were correlated with hypertension, SBPSD, SDBG, and AIP (p < 0.05). (6) An association was observed between the characteristics of retinal microangiopathy and vascular risk factors and the total imaging burden of CSVD (p < 0.05). Conclusions: (1) Hypertension, SBP variability, BG fluctuation, and AIP are independent vascular risk factors for CSVD. (2) Retinal microvessels are changed in patients with CSVD, and venous dilatation, decreased arteriovenous ratio, and vascular tortuosity are the main characteristics of the disease. (3) The characteristics of retinal microangiopathy are interactively correlated with the total imaging load and risk factors for CSVD and can be used as indicators of the severity of CSVD.
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Doenças de Pequenos Vasos Cerebrais , Hipertensão , Pressão Sanguínea/fisiologia , Doenças de Pequenos Vasos Cerebrais/complicações , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Doenças de Pequenos Vasos Cerebrais/epidemiologia , Humanos , Hipertensão/complicações , Hipertensão/epidemiologia , Imageamento por Ressonância Magnética , Fatores de RiscoRESUMO
Objective: To explore the value of brain structure magnetic resonance imaging combined with APOE-ε4 genotype in the early diagnosis and disease progression of elderly patients with vascular cognitive impairment no dementia (VCIND). Methods: The first stroke patients admitted to our hospital from March 2017 to December 2018 were collected, including 130 cases of vascular cognitive impairment no dementia (VCIND group) and 50 cases of the control group (NC group). The basic information of all subjects was recorded, and APOE-ε4 alleles of all subjects were detected. The neuropsychological test scale evaluated the cognitive psychology of the subjects, and they were scanned by multi-parameter MRI. After follow-up, VCIND patients were divided into the dementia group and the nondementia group. MRI scans were again performed, and the risk factors of VCIND patients developing dementia were analyzed. Results: Compared with the NC group, patients in the VCIND group had shorter years of education, more patients with hypertension, higher levels of homocysteine (Hcy), and lower cognitive ability. Patients with White Matter Volume (WMV), White Matter Hyperintensity (WMH), Lacunar Infarction (LI), elevated Fazekas scores, and APOE-ε4 gene carriers are more likely to develop VCIND. After 12 months of follow-up, compared with the nondementia group, the number of WMV, WMH, Fazekas scores, and APOE-ε4 gene carriers in the dementia group was significantly increased. In addition, the progression-free survival rate of APOE-ε4 gene carriers was significantly lower than that of nonAPOE-ε4 gene carriers. Conclusion: Years of education, hypertension, high levels of Hcy, elevated WMV, WMH, LI, and Fazekas scores, and carrying the APOE-ε4 gene are risk factors for VCIND in stroke patients. Craniocerebral structural MRI combined with APOE-ε4 genotype has a diagnostic role in the early diagnosis and disease progression of elderly patients with VCIND.
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Doença de Alzheimer , Apolipoproteína E4 , Disfunção Cognitiva , Hipertensão , Acidente Vascular Cerebral , Idoso , Doença de Alzheimer/patologia , Apolipoproteína E4/genética , Apolipoproteínas E , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/genética , Disfunção Cognitiva/patologia , Progressão da Doença , Diagnóstico Precoce , Genótipo , Humanos , Hipertensão/patologia , Imageamento por Ressonância MagnéticaRESUMO
Objective: The goals of this study are to assess the correlation between 24-hour ambulatory blood pressure (BP) variability and white matter lesions (WML) in patients with cerebral small vascular disease (CSVD) and to provide guidance for the prevention of WML. Methods: A total of 136 patients diagnosed with CSVD and essential hypertension were recruited and divided into two groups. The Fazekas scale was used to quantify the severity of WML. The basic information, BP levels, BP variability, and circadian rhythm changes across these groups were recorded and compared. Results: The control group consisted of 40 subjects without WML (Fazekas score = 0), and the WML group was composed of 96 patients with WML (Fazekas score ≥ 1). Patients in the WML group were then divided into three subgroups: mild WML (n = 43, Fazekas score = 1), moderate WML (n = 24, Fazekas score = 2), and severe WML (n = 29, Fazekas score = 3-4). Age, history of diabetes, and serum uric acid levels were significantly increased between the WML and control groups (P < 0.05). The levels of 24-hour mean diastolic BP (F = 3.158, P = 0.026) and daytime mean systolic BP (F = 3.526, P = 0.017) were significantly increased between the control and WML groups. There was no significant difference in the rhythmic classification of BP among all groups (P > 0.05). An ordered multinomial logistic regression analysis revealed that age, triglyceride levels, and nondipper BP were independent risk factors in WML. Conclusion: Age, history of diabetes, serum uric acid levels, 24-hour mean systolic level, and daily mean systolic BP level were significantly increased between the WML and control groups. Age, triglyceride levels, and nondipper BP were independent risk factors in WML in patients with CSVD, while the 24-hour dynamic blood pressure standard deviation and 24-hour dynamic blood pressure coefficient of variation were not associated with the occurrence of WML.
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Transtornos Cerebrovasculares , Hipertensão , Doenças Vasculares , Substância Branca , Pressão Sanguínea/fisiologia , Monitorização Ambulatorial da Pressão Arterial , Transtornos Cerebrovasculares/patologia , Estudos Transversais , Humanos , Hipertensão/complicações , Imageamento por Ressonância Magnética , Triglicerídeos , Ácido Úrico , Doenças Vasculares/patologia , Substância Branca/diagnóstico por imagem , Substância Branca/patologiaRESUMO
Thiamine is a key primary metabolite which is necessary for the viability of all organisms. It is a dietary requirement for mammals because only prokaryotes, fungi and plants are thiamine prototrophs. In contrast to the well documented biosynthetic mechanism in bacteria, much remains to be deciphered in plants. In this work, a tomato thiamine-auxotrophic (thiamineless, tl) mutant was characterized. The tl mutant occurs due to inactivation of LeTHIC transcription as a result of insertion of a large unknown DNA fragment in its 5'-untranslated region. Expression of wild-type LeTHIC in tl plants was able to complement the mutant to wild type. LeTHIC possessed the same function as E.cTHIC [an Escherichia coli 4-amino-5-hydroxymethyl-2-methylpyrimidine phosphate (HMP-P) synthase involved in synthesis of the pyrimidine moiety of thiamine] because expression of LeTHIC rescued THIC-deficient strains of E. coli under culture conditions without thiamine supplementation, suggesting that plants employ a bacteria-like route of pyrimidine moiety synthesis. LeTHIC is an Fe-S cluster protein localized in chloroplasts, and Fe is required for maintenance of its enzyme activity because Fe deficiency resulted in a significant reduction of thiamine content in tomato leaves. Further, we also showed that the expression of LeTHIC is tightly regulated at the transcriptional and post-transcriptional level by multiple factors, such as light, Fe status and thiamine pyrophosphate (TPP)-riboswitch. The results clearly demonstrated that a feedback regulation mechanism is involved in synthesis of the pyrimidine moiety for controlling thiamine synthesis in tomato. Our results provide a new insight into understanding the molecular mechanism of thiamine biosynthesis in plants.
Assuntos
Proteínas Ferro-Enxofre/metabolismo , Ferro/metabolismo , Proteínas de Plantas/metabolismo , Solanum lycopersicum/enzimologia , Tiamina/biossíntese , Regiões 5' não Traduzidas , Sequência de Aminoácidos , Proteínas de Arabidopsis/genética , Proteínas de Bactérias/genética , Sequência de Bases , Cloroplastos/metabolismo , DNA de Plantas/genética , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Teste de Complementação Genética , Proteínas Ferro-Enxofre/genética , Luz , Solanum lycopersicum/genética , Solanum lycopersicum/crescimento & desenvolvimento , Dados de Sequência Molecular , Fenótipo , Filogenia , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Pirimidinas/biossíntese , Riboswitch , Análise de Sequência de Proteína , Tiamina Pirofosfato/metabolismoRESUMO
It is a formidable challenge to use the traditional trial-and-error method to identify suitable catalysts for the photocatalytic degradation of volatile organic compounds (VOCs). In this work, by performing density functional theory calculations, we designed three Z-scheme g-CN/M2CO2 (M = Hf, Zr, and Sc) heterostructures, which not only exhibit favorable structure stability but also show promising ability for photocatalytic degradation of VOCs. The enhancement of the photocatalytic activity of these three Z-scheme systems can be ascribed to the low recombination rate of electron-hole pairs because photoelectrons migrated from the g-CN layer to the M2CO2 layer as well as the internal electric fields in the Z-scheme heterojunction. Among the three heterostructures, only g-CN/Zr2CO2 presents favorable spectra utilization under photoirradiation as well as the direct band gap. As a result, in the Z-scheme g-CN/Zr2CO2 heterostructure, the electrons in the conduction band of g-CN migrate to the holes in the valence band of the Zr2CO2 layer, which improves extraction and utilization of photogenerated electrons in the g-CN sheet. Moreover, the Z-scheme g-CN/Zr2CO2 system shows superior performance for photocatalytic VOC degradation in comparison with individual g-CN and Zr2CO2, which can be attributed to the enhanced VOC adsorption capacity as well as excellent ability to photoactivate O2 and H2O into â¢O2- and â¢OH radicals. Our findings pave a new promising way to facilitate the application of MXene-based materials for VOC photocatalytic degradation.
RESUMO
BACKGROUND: Cerebrovascular disease is a common clinical illness. Many patients with cerebrovascular disease can be accompanied by cognitive impairment. The exosomal microRNA (miRNA)-223-3p is related to vascular endothelial injury, synaptic function, inflammatory response, and other mechanisms. In this study, we investigated the levels of plasma exosomal miRNA-223-3p in patients with cerebral small vessel disease (CSVD), in order to determine whether it could be used as a more accessible potential biomarker for the early diagnosis and treatment of CSVD. This study aimed to explore whether the development of cognitive impairment can be explained by differentially expressed miRNA-223-3p by detecting the level of miRNA-223-3p, which is abundant in peripheral blood exosomes related to cognitive impairment in CSVD. METHODS: The three groups of participants included 40 patients with CSVD cognitive impairment (CSVDCI), 38 patients with CSVD, and 35 normal controls (NC). The real-time polymerase chain reaction (RT-PCR) was used to detect the expression level of blood exosomal miRNA-223-3p. In addition, we also studied the relationship between exosomal miRNA-223-3p and blood Hcy and C-reactive protein (CRP). Receiver-operating characteristic (ROC) curve analysis was used to evaluate the diagnostic efficacy of plasma exosomal miRNA-223-3p. RESULTS: The expression of exosomal miRNA-223-3p in CSVD increased, and the expression of miRNA-223-3p increased significantly with the occurrence of cognitive impairment. Exosomal miRNA-223-3p was positively correlated with the expression levels of Hcy and CRP in the blood. CONCLUSIONS: The expression of plasma exosomal miRNA-223-3p is associated with the development of cognitive impairment in patients with CSVD. It may be involved in the pathogenesis of CSVD and cognitive impairment, and can be used as a sensitive predictive biomarker.