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1.
J Chem Phys ; 160(23)2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38884398

RESUMO

The rotational spectrum of an acrolein-formaldehyde complex has been characterized using pulsed jet Fourier transform microwave spectroscopy complemented with quantum chemical calculations. One isomer has been observed in pulsed jets, which is stabilized by a dominant O=C⋯O tetrel bond (n → π* interaction) and a secondary C-H⋯O hydrogen bond. Splittings arising from the internal rotation of formaldehyde around its C2v axis were also observed, from which its V2 barrier was evaluated. It seems that when V2 equals or exceeds 4.61 kJ mol-1, no splitting of the spectral lines of the rotational spectrum was observed. The nature of the non-covalent interactions of the target complex is elucidated through natural bond orbital analysis. These findings contribute to a deeper understanding on the non-covalent interactions within the dimeric complex formed by two aldehydes.

2.
Mol Cell Endocrinol ; 592: 112315, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38878954

RESUMO

Diabetic cardiomyopathy (DCM) is characterized by oxidative damage and inflammatory responses. Myeloid differentiation protein 1 (MD1) exhibits antioxidant and anti-inflammatory properties. However, the specific role of MD1 in DCM has yet to be elucidated. This study aims to investigate the role of MD1 in DCM and to elucidate the underlying mechanisms. We utilized a gain-of-function approach to explore the involvement of MD1 in DCM. Diabetes was induced in MD1-transgenic (MD1-TG) mice and their wild-type (WT) counterparts via streptozotocin (STZ) injection. Additionally, a diabetes cell model was established using H9c2 cells exposed to high glucose levels. We conducted comprehensive evaluations, including pathological analyses, echocardiography, electrocardiography, and molecular assessments, to elucidate the underlying mechanisms of MD1 in DCM. Notably, MD1 expression was reduced in the hearts of STZ-induced diabetic mice. Overexpression of MD1 significantly improved cardiac function and markedly inhibited ventricular pathological hypertrophy and fibrosis in these mice. Furthermore, MD1 overexpression resulted in a substantial decrease in myocardial reactive oxygen species (ROS) accumulation, mitigating myocardial oxidative stress and reducing the levels of inflammation-related markers such as IL-1ß, IL-6, and TNF-α. Mechanistically, MD1 overexpression inhibited the activation of the TLR4/STAT3 signaling pathway, as demonstrated in both in vivo and in vitro experiments. The overexpression of MD1 significantly impeded pathological cardiac remodeling and improved cardiac function in STZ-induced diabetic mice. This effect was primarily attributed to a reduction in ROS accumulation and mitigation of myocardial oxidative stress and inflammation, facilitated by the inhibition of the TLR4/STAT3 signaling pathway.

3.
Clin Epigenetics ; 15(1): 194, 2023 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-38098098

RESUMO

BACKGROUND: Clopidogrel resistance profoundly increases the risk of major cardiovascular events in coronary artery disease (CAD) patients. Here, we comprehensively analyse global m6A modification alterations in clopidogrel-resistant (CR) and non-CR patients. METHODS: After RNA isolation, the RNA transcriptome expression (lncRNA, circRNA, and mRNA) was analysed via RNA-seq, and m6A peaks were identified by MeRIP-seq. The altered m6A methylation sites on mRNAs, lncRNAs, and circRNAs were identified, and then, GO and KEGG pathway analyses were performed. Through joint analysis with RNA-seq and MeRIP-seq data, differentially expressed mRNAs harbouring differentially methylated sites were identified. The changes in m6A regulator levels and the abundance of differentially methylated sites were measured by RT-PCR. The identification of m6A-modified RNAs was verified by m6A-IP-qPCR. RESULTS: The expression of 2919 hypermethylated and 2519 hypomethylated mRNAs, 192 hypermethylated and 391 hypomethylated lncRNAs, and 375 hypermethylated and 546 hypomethylated circRNAs was shown to be altered in CR patients. The m6A peaks related to CR indicated lower mark density at the CDS region. Functional enrichment analysis revealed that inflammatory pathways and insulin signalling pathways might be involved in the pathological processes underlying CR. The expression of mRNAs (ST5, KDM6B, GLB1L2, and LSM14B), lncRNAs (MSTRG.13776.1 and ENST00000627981.1), and circRNAs (hsa_circ_0070675_CBC1, hsa-circRNA13011-5_CBC1, and hsa-circRNA6406-3_CBC1) was upregulated in CR patients, while the expression of mRNAs (RPS16 and CREG1), lncRNAs (MSTRG.9215.1), and circRNAs (hsa_circ_0082972_CBC1) was downregulated in CR patients. Moreover, m6A regulators (FTO, YTHDF3, and WTAP) were also differentially expressed. An additional combined analysis of gene expression and m6A peaks revealed that the expression of mRNAs (such as ST5, LYPD2, and RPS16 mRNAs) was significantly altered in the CR patients. CONCLUSION: The expression of m6A regulators, the RNA transcriptome, and the m6A landscape was altered in CR patients. These findings reveal epitranscriptomic regulation in CR patients, which might be novel therapeutic targets in future.


Assuntos
Doença da Artéria Coronariana , RNA Longo não Codificante , Humanos , Doença da Artéria Coronariana/tratamento farmacológico , Doença da Artéria Coronariana/genética , Clopidogrel/farmacologia , RNA Circular/genética , RNA Longo não Codificante/genética , Transcriptoma , Metilação de DNA , Adenosina/farmacologia , RNA Mensageiro/genética , Histona Desmetilases com o Domínio Jumonji , Dioxigenase FTO Dependente de alfa-Cetoglutarato
4.
Phys Chem Chem Phys ; 25(45): 31281-31291, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37955344

RESUMO

Rotational spectroscopy represents an invaluable tool for several applications: from the identification of new molecules in interstellar objects to the characterization of van der Waals complexes, but also for the determination of very accurate molecular structures and for conformational analyses. In this work, we used high-resolution rotational spectroscopic techniques in combination with high-level quantum-chemical calculations to address all these aspects for two isomers of cyanofuran, namely 2-furonitrile and 3-furonitrile. In particular, we have recorded and analyzed the rotational spectra of both of them from 6 to 320 GHz; rotational transitions belonging to several singly-substituted isotopologues have been identified as well. The rotational constants derived in this way have been used in conjunction with computed rotation-vibration interaction constants in order to derive a semi-experimental equilibrium structure for both isomers. Moreover, we observed the rotational spectra of four different intermolecular adducts formed by furonitrile and water, whose identification has been supported by a conformational analysis and a theoretical spectroscopic characterization. A semi-experimental determination of the intermolecular parameters has been achieved for all of them and the results have been compared with those obtained for the analogous system formed by benzonitrile and water.

5.
Artigo em Inglês | MEDLINE | ID: mdl-37256416

RESUMO

BACKGROUND: C1q/tumor necrosis factor-related protein 5 (CTRP5) has been reported to be a crucial regulator in cardiac ischemia/reperfusion (I/R) injury. Nevertheless, the potential role of CTRP5 in doxorubicin (DOX)-induced cardiotoxicity and the potential mechanisms remain largely unclear. METHODS: We overexpressed CTRP5 in the hearts using an adeno-associated virus 9 (AAV9) system through tail vein injection. C57BL/6 mice were subjected to DOX (15 mg/kg/day, i.p.) to generate DOX-induced cardiotoxicity for 4 weeks. Subsequently, cardiac staining and molecular biological analysis were performed to analyze the morphological and biochemical effects of CTRP5 on the cardiac injury. H9c2 cells were used for validation in vitro. RESULTS: CTRP5 expression was down-regulated after DOX treatment both in vivo and in vitro. CTRP5 overexpression significantly attenuated DOX-induced cardiac injury, cardiac dysfunction, inhibited oxidative stress and inflammatory response. Mechanistically, CTRP5 overexpression markedly decreased the protein expression of toll-like receptor 4 (TLR4), NLRP3, cleaved caspase-1 and caspase-1, indicating TLR/NLRP3 signaling contributes to the cardioprotective role of CTRP5 in DOX-induced cardiotoxicity. CONCLUSIONS: Together, our findings demonstrated that CTRP5 overexpression could protect the heart from oxidative stress and inflammatory injury induced by DOX through inhibiting TLR4/NLRP3 signaling, suggesting that CTRP5 might be a potential therapeutic target in the prevention of DOX-induced cardiotoxicity.

6.
Eur J Pharmacol ; 944: 175547, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-36708978

RESUMO

Sacubitril/valsartan has a noteworthy advantage in improving ventricular remodelling, as well as reducing cardiovascular mortality and the rate of heart failure (HF) readmission. However, clinically, some patients with HF still have low sensitivity to sacubitril/valsartan, indicating sacubitril/valsartan resistance (SVR). A total of 46 patients with HF after AMI (23 SVR and 23 non-sacubitril/valsartan resistance (NSVR)) were selected. Five SVR and 5 matched NSVR samples were screened for differentially expressed ncRNAs along with mRNAs. A total of 124 differentially expressed miRNAs, 137 circRNAs, 237 lncRNAs and 50 mRNAs were screened by RNA sequencing technology. After quantitative real-time PCR (qRT‒PCR) verification of selected biomarkers in 18 pairs of samples, we found that for patients with SVR, hsa-miR-543, hsa-miR-642b-5p, hsa-miR-760, hsa_circ_0137499, ENST00000474394, ENST00000528337, E2F1, NEAT1, and YTHDF2 were upregulated, and hsa-miR-424-5p, hsa-miR-21-3p, hsa_circRNA_0003275, hsa_circRNA_0004494, hsa_circ_0093522, ENST00000467951, ENST00000558177, ACTA2, ANPEP, and CAMP were downregulated. Then, with the help of our constructed ceRNA network and functional annotation enrichment, we speculated that inflammatory pathways (such as the apelin signalling pathway) and lipid metabolism pathways (such as fatty acid metabolism) may be involved in the regulation of SVR. These discoveries lay a foundation for further mechanistic research and provide a direction for individualized drug administration.


Assuntos
Insuficiência Cardíaca , MicroRNAs , Infarto do Miocárdio , Humanos , RNA Circular/genética , Transcriptoma , MicroRNAs/genética , RNA Mensageiro/genética , Valsartana
7.
J Clin Lab Anal ; 37(1): e24821, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36550638

RESUMO

BACKGROUND: Aspirin resistance (AR) results in major adverse cardiovascular events, and DNA methylation might participate in the regulation of this pathological process. METHODS: In present study, a sum of 35 patients with AR and 35 non-AR (NAR) controls were enrolled. Samples from 5 AR and 5 NAR were evaluated in an 850 BeadChip DNA methylation assay, and another 30 AR versus 30 NAR were evaluated to validate the differentially methylated CpG loci (DML). Then, qRT-PCR was used to investigate the target mRNA expression of genes at CpG loci. Finally, Gene Ontology (GO) as well as Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed to reveal the enriched pathways. RESULTS: The AR and NAR groups displayed significant differences in DNA methylation at 7707 positions, with 270 hypermethylated sites (e.g., cg09555818 located in APOC2) and 7437 sites hypomethylated sites (e.g., cg26828689 located in SLC12A5). Six DML were validated by pyrosequencing, and it was confirmed that DNA methylation (cg16391727, cg21008208, cg21293749, and cg13945576) was related to the increasing risk of AR. The relative mRNA expression of the ROR1 gene was also associated with AR (p = 0.007), suggesting that the change of cg21293749 in DNA methylation might lead to differential ROR1 mRNA expression, ultimately resulting in AR. Furthermore, the identified differentially methylated sites were associated with the molecular pathways such as circadian rhythms and insulin secretion. CONCLUSION: Hence, the distinct DNA methylation might play a vital role in the biological regulation of AR through the pathways such as circadian rhythms.


Assuntos
Síndrome Coronariana Aguda , Metilação de DNA , Humanos , Metilação de DNA/genética , Síndrome Coronariana Aguda/tratamento farmacológico , Síndrome Coronariana Aguda/genética , Aspirina/farmacologia , RNA Mensageiro/genética , Ilhas de CpG/genética
8.
Environ Sci Pollut Res Int ; 30(1): 2029-2041, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35925463

RESUMO

The purpose of this study was to explore the research hotspots and trends of Kinesio Taping in the last decade and provide new sights in future studies. Publications in the area of Kinesio Taping were searched from the Web of Science Core Collection database between 2011 and 2020. Citespace software was used to analyze data on countries/regions, institutions, authors, co-cited references, and keywords. A total of 677 publications were obtained in the last decade. We identified the most prolific countries, institutions, and authors in the field of Kinesio Taping from 2011 to 2020. The annual number of publications showed an upward trend. The most prolific country and institution were Turkey and Hacettepe University, respectively. The author with the biggest number of publications was Gul Baltaci from Turkey. The top 5 most frequent keywords were "pain", "tape", "strength", "exercise", and "reliability". The keywords with the highest centrality were "proprioception", followed by "reliability", "clinical trial", "ankle", and "pain". Ten clusters were found and the biggest one was "quadricep". The top 9 keywords with the strongest bursts were detected and "trial" had the highest burst strength. The results from the bibliometric analysis provide hotspots and trends in the field of Kinesio Taping. It is still in the development stage of the past decade. Pain relief, sports injury prevention and treatment, and proprioception enhancement to improve postural control were the hotspots from 2011 to 2020. High-quality trials and standardized criteria for applications are needed in the future.


Assuntos
Bibliometria , Exercício Físico , Humanos , Bases de Dados Factuais , Instalações de Saúde , Dor
9.
Dis Markers ; 2022: 3040521, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36561112

RESUMO

Background: Resistin is closely related to cardiovascular diseases, and this study is aimed at examining the role of resistin in doxorubicin- (DOX-) induced cardiac injury. Methods: First, 48 mice were divided into 2 groups and treated with saline or DOX, and the expression of resistin at different time points was examined (N = 24). A total of 40 mice were pretreated with the antiresistin neutralizing antibody (nAb) or isotype IgG for 1 hour and further administered DOX or saline for 5 days. The mice were divided into 4 groups: saline-IgG, saline-nAb, DOX-IgG, and DOX-nAb (N = 10). Cardiac injury, cardiomyocyte apoptosis, inflammatory factors, and the biomarkers of M1 and M2 macrophages in each group were analyzed. Result: DOX administration increased the expression of resistin. DOX treatment exacerbated the loss of body and heart weight and cardiac vacuolation in mice. The antiresistin nAb reversed these conditions, downregulated the expression of myocardial injury markers, and decreased apoptosis. In addition, the antiresistin nAb decreased p65 pathway activation, decreased M1 macrophage differentiation and the expression of related inflammatory factors, and increased M2 macrophage differentiation and the expression of related inflammatory factors. Conclusion: The antiresistin nAb protected against DOX-induced cardiac injury by reducing cardiac inflammation and may be a promising target to relieve DOX-related cardiac injury.


Assuntos
Doenças Cardiovasculares , Resistina , Camundongos , Animais , Doxorrubicina/efeitos adversos , Coração , Apoptose , Imunoglobulina G , Camundongos Endogâmicos C57BL , Cardiotoxicidade
10.
J Phys Chem Lett ; 13(42): 9934-9940, 2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36259781

RESUMO

Phenyl isocyanide has been chosen as a prototype to probe the π-π interaction modulated by the -NC group, which has a chameleonic nature with two main resonance forms showing a triple bond and being carbenoid. The rotational spectroscopic investigation complemented with theoretical analyses indicates that the phenyl isocyanide dimer has a scissor-like configuration controlled by dispersive forces along with the formation of π-π stacking. This is the first rotational spectroscopic evidence, to the best of our knowledge, that the mono-substitution by an -NC group on benzene can activate the meta position in forming noncovalent interactions. This work also provides experimental evidence on the importance of substituent effects in modulating π-π stacked structures, as well as practical proof of a biased interaction behavior of isocyanide-substituted aromatic molecules.

11.
Mediators Inflamm ; 2022: 3306559, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36262545

RESUMO

Background: Visfatin is an adipocytokine that has been demonstrated to be involved in cardiovascular diseases. This study aims at determining the role of visfatin in sepsis-induced cardiac injury and identify its possible mechanisms. Methods: Dynamic changes in visfatin expression in mice with lipopolysaccharide- (LPS-) induced septicemia were measured. Additionally, mice were pretreated with visfatin and further administered LPS to observe the effects of visfatin on cardiac injury. Finally, septic mice were also pretreated with JSH-23 to investigate whether visfatin regulates cardiac injury via the NF-κB p65 pathway. Results: Visfatin expression levels in both the heart and serum were increased in LPS-treated mice and peaked at 6 hours, and visfatin was derived from cardiac macrophages. In septic mice, pretreatment with visfatin reduced the survival rate, worsened cardiac dysfunction, and increased the expression of cardiac injury markers, including creatine kinase myocardial bound (CK-MB) and lactate dehydrogenase (LDH). Treatment with visfatin also increased the infiltration of CD3+ cells and F4/80+ cells, amplified the cardiac inflammatory response, and elevated myocardial cell apoptosis. Treatment with JSH-23 reversed the effects of visfatin in septic mice. Conclusions: This study showed that visfatin amplifies the cardiac inflammatory response and aggravates cardiac injury through the p65 signaling pathway. Visfatin may be a clinical target for preventing cardiac injury in sepsis.


Assuntos
Traumatismos Cardíacos , Nicotinamida Fosforribosiltransferase , Sepse , Animais , Camundongos , Adipocinas , Creatina Quinase/metabolismo , Lactato Desidrogenases/metabolismo , Lipopolissacarídeos/toxicidade , NF-kappa B/metabolismo , Nicotinamida Fosforribosiltransferase/metabolismo , Sepse/tratamento farmacológico , Sepse/metabolismo , Transdução de Sinais , Citocinas/metabolismo
12.
Front Cardiovasc Med ; 9: 961700, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36247465

RESUMO

Background: It has been reported that sacubitril/valsartan can improve cardiac function in acute myocardial infarction (AMI) patients complicated by heart failure (HF). However, a number of patients cannot be treated successfully; this phenomenon is called sacubitril/valsartan resistance (SVR), and the mechanisms remain unclear. Methods: In our present research, the expression profiles of transfer RNA (tRNA)-derived small RNAs (tsRNAs) in SVR along with no sacubitril/valsartan resistance (NSVR) patients were determined by RNA sequencing. Through bioinformatics, quantitative real-time PCR (qRT-PCR), and cell-based experiments, we identified SVR-related tsRNAs and confirmed their diagnostic value, predicted their targeted genes, and explored the enriched signal pathways as well as regulatory roles of tsRNAs in SVR. Results: Our research indicated that 36 tsRNAs were upregulated and that 21 tsRNAs were downregulated in SVR. Among these tsRNAs, the expression of tRF-59:76-Tyr-GTA-2-M3 and tRF-60:76-Val-AAC-1-M5 was upregulated, while the expression of tRF-1:29-Gly-GCC-1 was downregulated in the group of SVR. Receiver operating characteristic (ROC) curve analysis demonstrated that these three tsRNAs were potential biomarkers of the therapeutic heterogeneity of sacubitril/valsartan. Moreover, tRF-60:76-Val-AAC-1-M5 might target Tnfrsf10b and Bcl2l1 to influence the observed therapeutic heterogeneity through the lipid and atherosclerosis signaling pathways. Conclusion: Hence, tsRNA might play a vital role in SVR. These discoveries provide new insights for the mechanistic investigation of responsiveness to sacubitril/valsartan.

13.
Front Public Health ; 10: 1016016, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36311592

RESUMO

Objectives: To examine the association of protein intake from different sources with cognitive decline. Methods: Our analysis included 3,083 participants aged 55-93 years from the China Health and Nutrition Survey. Cognition was assessed in 1997, 2000, 2004, 2006, and 2015. Diet intake was assessed using weighing methods in combination with 24-h dietary recalls for three consecutive days at each survey. Results: Participants consumed 13.94% of energy intake from total protein, with 11.47 and 2.47% from plant and animal sources, respectively. During a follow-up of 9 years, participants in quintile 5 of plant protein intake (% energy) had a higher risk [odds ratio (95% CI): 3.03 (1.22-7.53)] of cognitive decline compared with those in quintile 1. Higher animal protein intake (% total protein) was associated with a lower risk of cognitive decline [odds ratio (95% CI) for quintile 5 vs. quintile 1: 0.22 (0.07-0.71)]. Grains (plant source) protein intake was inversely but fish/shrimp and poultry (animal source) protein intake were positively associated with change in cognitive Z-score. Conclusion: Increasing animal protein consumption in a population with plant dominant diets may help to prevent cognitive decline.


Assuntos
Disfunção Cognitiva , Vida Independente , Animais , Dieta , Ingestão de Alimentos , Cognição
14.
J Cardiovasc Pharmacol ; 80(6): 804-812, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-35856909

RESUMO

ABSTRACT: Grb2-associated binding protein 1 (Gab1), an intracellular scaffolding adaptor, was involved in several cardiovascular diseases. However, the role of Gab1 in doxorubicin (DOX)-induced cardiotoxicity remains largely unknown. The present study investigated whether Gab1 protected against DOX-induced cardiotoxicity and the underlying mechanism. We overexpressed Gab1 in the hearts using an adeno-associated virus 9 system through tail vein injection. C57BL/6 mice were subjected to DOX (15 mg/kg/d, i.p.) to generate DOX-induced cardiotoxicity. Echocardiography, histological analysis, immunofluorescence and enzyme-linked immunosorbent assay (ELISA) kits, Western blotting, and quantitative real-time polymerase chain reaction (PCR) evaluated DOX-induced cardiotoxicity and the underlying mechanisms. Myocardial Gab1 protein and messenger RNA (mRNA) levels were markedly decreased in DOX-administered mice. Overexpression of Gab1 in myocardium significantly improved cardiac function and attenuated cardiac oxidative stress, inflammatory response, and apoptosis induced by DOX. Mechanistically, we found that PI3K/Akt signaling pathway was downregulated after DOX treatment, and Gab1 overexpression activated PI3K/Akt signaling pathway, whereas PI3K/Akt signaling pathway inhibition abolished the beneficial effect of Gab1 overexpression in the heart. Collectively, our results indicated that Gab1 is essential for cardioprotection against DOX-induced oxidative stress, inflammatory response, and apoptosis by mediating PI3K/Akt signaling pathway. And cardiac gene therapy with Gab1 provides a novel therapeutic strategy against DOX-induced cardiotoxicity.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Apoptose , Cardiotoxicidade , Doxorrubicina , Estresse Oxidativo , Animais , Camundongos , Proteínas Adaptadoras de Transdução de Sinal/genética , Doxorrubicina/toxicidade , Camundongos Endogâmicos C57BL , Fosfatidilinositol 3-Quinases , Transdução de Sinais
15.
Spectrochim Acta A Mol Biomol Spectrosc ; 282: 121677, 2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-35908502

RESUMO

Rotational spectrum of the 1:1 anisole-CO2 complex has been investigated using a pulsed jet Fourier transform microwave spectrometer supplemented with quantum chemical calculations. In the pulsed jet, only one isomer has been observed which is characterized by a dominant C···O tetrel bond and two CH···OCO2 weak hydrogen bonds. Different theoretical methods predict different orders of relative energies of plausible conformations. The experimental observation is most consistent with the theoretical estimation at the B3LYP-D3(BJ)/6-311++G(d,p) level of theory. Johnson's non-covalent interaction, quantum theory of atoms in molecules and natural bond orbital analyses have been applied to better understand the nature of non-covalent interactions at play in the anisole-CO2 complex.

16.
J Phys Chem A ; 126(4): 623-629, 2022 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-35050614

RESUMO

Rotational spectra of the 2-ethynylpyridine monomer and its monohydrate have been characterized by pulsed jet Fourier transform microwave spectroscopy complemented with quantum chemical calculations. The measurements of rotational transitions of the 2-ethynylpyridine monomer and its eight monosubstituted isotopologues (15N and 13C) in natural abundances allow an accurate structural description of the skeleton of 2-ethynylpyridine. For the monohydrate, only the most stable isomer, stabilized by an O-H···N and a secondary C-H···O hydrogen bonds, has been observed in the supersonic jet. Johnson's noncovalent interaction and quantum theory of atoms in molecules analyses have been performed and compared with results for several ortho-substituted pyridine derivatives to elucidate the general trend in their binding energies.

17.
Polymers (Basel) ; 13(20)2021 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-34685233

RESUMO

A time-temperature-transformation-viscosity (TTT-η) diagram can reflect changes in the physical states of a resin, which take on significance for the study of the curing process of polyurethane resin lenses. Coupling the differential scanning calorimetry (DSC) test, the curing kinetic parameters of 1,4-bis(isocyanatomethyl)cyclohexane (H6XDI)/2,3-bis((2-mercaptoethyl)thio)-1-propanethiol (BES) polyurethane system were obtained. By phenomenological modeling, the relationships between degree, temperature, and time were obtained. An isothermal DSC test was carried out at 423 K. Based on the DiBenedetto equation, the relationships between glass transition temperature, degree of cure, and time were obtained, and the glass transition temperature was thus correlated with temperature and time. The gelation time at different temperatures was measured by rotary rheometry, and the relationship between gelation time and gelation temperature was established. The time-temperature-transformation (TTT) diagram of H6XDI/BES system was constructed accordingly. Subsequently, a six-parameter double Arrhenius equation was used as the basis for the rheological study. The viscosity was examined during the curing process. The TTT-η diagram was obtained, which laid the theoretical foundation for the optimization and setting of processing parameters.

18.
Br J Radiol ; 94(1118): 20201030, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33237823

RESUMO

OBJECTIVE: We sought to explore the relationships between multiple chemokines with spirometry, inflammatory mediators and CT findings of emphysema, small airways disease and bronchial wall thickness. METHODS: All patients with COPD (n = 65) and healthy control subjects (n = 23) underwent high-resolution CT, with image analysis determining the low attenuation area (LAA), ratio of mean lung attenuation on expiratory and inspiratory scans (E/I MLD) and bronchial wall thickness of inner perimeter of a 10-mm diameter airway (Pi10). At enrollment, subjects underwent pulmonary function studies, chemokines and inflammatory mediators measurements. RESULTS: Multiple chemokines (CCL2, CCL3, CCL5, CX3CL1, CXCL8, CXCL9, CXCL10, CXCL11 and CXCL12) and inflammatory mediators (MMP-9, MMP-12, IL-18 and neutrophil count) were markedly increased in the serum of COPD patients compared with healthy controls. There were associations between small airway disease (E/I MLD) and CCL11, CXCL8, CXCL10, CXCL11, CXCL12 and CX3CL1. Especially CXCL8 and CX3CL1 are strongly associated with E/I MLD (r = 0.74, p < 0.001; r = 0.76, p < 0.001, respectively). CXCL8, CXCL12 and CX3CL1 were moderately positively correlated with emphysema (%LAA) (r = 0.49, p < 0.05; r = 0.51, p < 0.05; r = 0.54, p < 0.01, respectively). Bronchial wall thickness (Pi10)showed no significant differences between the COPD and healthy controls,,but there was an association between Pi10 and FEV1% in COPD patients (r=-0.420, p = 0.048). Our statistical results showed that there were not any associations between airway wall thickness (Pi10) and chemokines. CONCLUSION: Pulmonary chemokines levels are closely associated with the extent of gas trapping, small airways disease and emphysema identified on high-resolution chest CT scan. ADVANCES IN KNOWLEDGE: This study combines quantitative CT analysis with multiplex chemokines and inflammatory mediators to identify a new role of pathological changes in COPD.


Assuntos
Quimiocinas/sangue , Doença Pulmonar Obstrutiva Crônica/sangue , Doença Pulmonar Obstrutiva Crônica/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , China , Estudos de Avaliação como Assunto , Feminino , Humanos , Pulmão/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
19.
Public Health Genomics ; 23(1-2): 20-25, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31982877

RESUMO

OBJECTIVE: Accumulated evidence suggests that ATP-binding cassette A1 transporter (ABCA1) contributes to secreting insulin in pancreatic ß-cells and amyloid beta formation. This study aimed to investigate the association between three single nucleotide polymorphisms (SNPs) of ABCA1 and susceptibility to type 2 diabetes mellitus (T2DM) in a Han Chinese population. METHODS: A total of 996 T2DM patients and 1,002 controls were included in the study. Three SNPs in the ABCA1 gene, i.e., rs2230806 (R219K), rs1800977 (C69T), and rs9282541 (R230C), were genotyped by SNaPshot. A genotype model, an allele model, a dominant model, and a recessive model were used to assess susceptibility to T2DM. RESULTS: There were significant associations between rs1800977 and T2DM in different genetic models (TT vs. CC, OR = 0.591 [0.446-0.793], p < 0.001; T vs. C, OR = 0.835 [0.735-0.949], p = 0.006; recessive model, OR = 0.583 [0.449-0.756], p < 0.001). There were also significant associations between rs9282541 and T2DM in different genetic models (CT vs. CC, OR = 1.690 [0.807-1.005], p = 0.048; T vs. C, OR = 1.756 [0.694-1.060], p = 0.029; dominant model, OR = 1.735 [0.715-1.034], p = 0.037). CONCLUSION: Our case-control study showed that the two SNPs rs1800977 and rs9282541 in the ABCA1 gene are significantly associated with susceptibility to T2DM in our Han Chinese population. Study of further mechanisms should be performed before application to clinical therapy.


Assuntos
Transportador 1 de Cassete de Ligação de ATP/genética , Diabetes Mellitus Tipo 2 , Estudos de Casos e Controles , China/epidemiologia , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/genética , Feminino , Predisposição Genética para Doença , Testes Genéticos/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único
20.
Nanomaterials (Basel) ; 10(1)2020 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-31940935

RESUMO

In this work, the effect of modified graphene oxide and polytetrafluoroethylene (PTFE) on the tribological and anticorrosion properties of waterborne polyurethane (WPU) was studied. The modified graphene oxide (MGO) was obtained by the surface functionalization modification of graphene oxide (GO) with isophorone diisocyanate (IPDI), and MGO/WPU composite coating and MGO-PTFE/WPU composite coating with different mass fractions of MGO were prepared. The tribological and electrochemical experiment results demonstrated that the tribological properties of the coating and the corrosion resistance of the worn coating were effectively enhanced under the synergistic effect of MGO and PTFE. Finally, a mechanism was proposed to explain the improvement in anticorrosion performance of the worn coating.

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