ABSTRACT
A protocol for the construction of an angular tricyclic benzofuran skeleton based on the C-H activation strategy has been established. Different phthalide lactones on this skeleton can be easily assembled with various side chains by using C-H activation with aldehydes and subsequent reduction. This skeleton provides a versatile and crucial motif for the total synthesis of naturally occurring angular tricyclic benzofurans and their derivatives. Based on this protocol, the improved total syntheses of daldinin A and annullatin D were achieved in yields of 17.3 and 7.6%, respectively.
ABSTRACT
In this paper, a dual-band metasurface (MS) generating multiple orbital angular momentum (OAM) beams independently in full polarizations is proposed. First, the design principle of controlling full polarizations independently is analyzed. Second, the frequency selective surface is introduced to the meta-atom design that ensures the meta-atom operates at Ku- and Ka-band independently, while, at each band, sixteen optimized meta-atoms realize the high reflection amplitude and enough phase coverage. Next, the optimized dual-band meta-atom controlling full polarizations independently is utilized to design the MS, which could generate eight independent OAM beams including the x-polarized, y-polarized, left hand circularly polarized, and right hand circularly polarized OAM beams at dual-band. Finally, the MS is designed, fabricated, and measured. Both simulated and measured results verify that the proposed MS could generate multiple OAM beams in full polarizations at dual-band, showing the perspective in the OAM-based area, such as the wireless communication, target detection, and security encryption.
ABSTRACT
In this paper, by elaborately splicing multiple transmissive metasurfaces (MSs) featuring polarization isolation, multiple linear polarized (LP) vortex beams are generated simultaneously and independently in different directions. Specifically, by carefully optimizing the radius of the array and the distance between the MS and array, each MS generates a well-performed deflection vortex beam with a low side-lobe level and little diffraction, resulting in a minor effect on other deflection vortex beams. Subsequently, four transmissive MSs are elaborately spliced, showing the polarization isolation characteristic between the adjacent MS, and thereby each MS is only illuminated by the respective antenna array. In addition, each MS only generates the desired LP vortex beam, and the corresponding cross-polarization is suppressed. Finally, the simulation and measurement results show that multiple LP vortex beams carrying different orbital angular momentum (OAM) modes are generated simultaneously and independently in different directions, verifying the effectiveness of the proposed method.
ABSTRACT
In this paper, we propose the use of metasurfaces to enhance evanescent wave coupling to improve the wireless power transfer (WPT) efficiency of multiple receivers. A 4 × 4 negative permeability metasurface is designed and placed between the transmitter (Tx) and receiver (Rx) coils for the greatest improvement in transfer efficiency. Through the analysis of the number and position topologies of Rx coils, the efficiency can be greatly improved; the maximum efficiency at longer transmission distances is achieved through the 4 × 4 negative permeability metasurface in the multiple-receiver system. We show with simulation and measurement results that the power transfer efficiency of the system can be improved significantly by integrating metasurfaces. The maximum transfer efficiency is achieved in a multiple-receiver WPT system when the number and topology of Rx coils is case 0 of single transmitter-three receivers (STTR). The results show that the total efficiency of the multiple receivers WPT system can be as high as 97%.
ABSTRACT
BACKGROUND: We aimed to explore the biomarkers associated with atrial fibrillation (AF) with mitral regurgitation (MR). METHODS: The gene expression profile data GSE115574 were downloaded from Gene Expression Omnibus database, which were obtained from patients with degenerative MR with AF and sinus rhythm (SR). The differentially expressed genes (DEGs) in samples of AF with MR compared with those of SR with MR were selected, followed by functional enrichment analysis, protein-protein interaction (PPI) network analysis, transcription factor (TF) prediction, and drug-gene interaction prediction. RESULTS: By comparing the genes' expression profiles between AF with MR and SR with MR, 379 DEGs were obtained. The upregulated genes, such as NMNAT2, LDHB, and hexosaminidase subunit beta (HEXB), were significantly enriched in metabolic pathways. Hub genes, such as amyloid beta precursor protein (APP), CDH2, SPP1, and STC2, were significantly associated with functions related to extracellular matrix organization and vitamin D response. Additionally, two TFs, PRDM3 and LSM6, were predicted for the key module genes. APP predicted the most drug molecules, that is, 22 molecules, and SPP1 predicted 10 drug molecules. CONCLUSIONS: Dysregulation of the metabolic pathway may play a critical role in AF with MR. Changes in functions related to the extracellular matrix and vitamin D response may also be associated with AF progression in patients with MR. Furthermore, APP, STC2, and SPP1 may serve as potential therapeutic targets of AF.
Subject(s)
Atrial Fibrillation/genetics , Biomarkers/analysis , Mitral Valve Insufficiency/genetics , Transcriptome , Atrial Fibrillation/metabolism , Gene Expression Regulation , Metabolic Networks and Pathways/genetics , Mitral Valve Insufficiency/metabolismABSTRACT
BACKGROUND: The aim of this study was to identify downstream target genes and pathways regulated by THZ1 in nasopharyngeal carcinoma (NPC). METHODS: The gene expression profile of GSE95750 in two NPC cell lines, untreated group and treated with THZ1 group, was analyzed. Differentially expressed genes (DEGs) were compared using the R-software. Then Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes pathways (KEGG) was analyzed using Database for Annotation, Visualization, and Integrated Discovery (DAVID). Cytoscape was used for protein-protein interaction (PPI) analysis. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used to verified the gene expression. RESULTS: We identified 25 genes with increased expression and 567 genes with decreased expression in THZ1-treated NPC cells. The top 10 significantly DEGs between untreated group and THZ1 treated group were identified by qRT-PCR and the results were in agreement with RNA-seq. The total 592 DEGs were found enriched in 1,148 GO terms and 38 KEGG pathways. The most important enriched pathways identified were cell cycle related, and several related node genes were identified, such as CDC6, CDC34, CDK7, CDK9, CCNA2, CCNB1, CDT1, KIF11, LIN9, PLK1, and POLR family, which consistent with RNA-seq. CONCLUSIONS: Our results emphasize the differential genes and pathways occurring in THZ1-treated NPC cells, which increases our understanding of the anti-tumor mechanisms of THZ1.
ABSTRACT
BACKGROUND AND AIMS: Glucose and lipid metabolism are major prognostic indicators of coronary heart disease. The ratio of plasma glycosylated hemoglobin A1c (HbA1c) to apolipoprotein A-l (ApoA-l) is an indirect measure of insulin resistance. The study aimed to evaluate whether the HbA1c/ApoA-1 ratio can predict the prognosis in patients with the acute coronary syndrome (ACS). METHODS AND RESULTS: A total of 476 ACS patients diagnosed by coronary angiography were enrolled in this longitudinal, observational, retrospective study. Plasma HbA1c, fasting blood glucose and lipid profile were measured. Patients were stratified according to the tertiles of HbA1c/ApoA-l levels. Cox proportional hazard model was used to examine the predictive value of HbA1c/ApoA-l for study endpoints. The association between the Log HbA1c/ApoA-l ratio and major adverse cardiovascular events (MACEs) was estimated using multiple logistic regression. Baseline characteristics showed a mean age of 66 ± 8 years, and 52.5% were hypertensive, 26.8% diabetic, and 54.5% current or prior smokers. During a mean follow-up period of 22.3 ± 1.7 months, 59 deaths occurred. After adjusting for age, gender, smoking, hypertension, diabetes, and coronary artery disease severity, patients in the highest HbA1c/ApoA-l ratio tertile had a 4.36-fold increased risk of mortality compared with those in the lowest tertile. The multivariate logistic regression showed that the Log HbA1c/ApoA-l ratio was associated with MACEs (Odds ratio 2.95, p = 0.013). CONCLUSION: After adjusting for traditional cardiovascular risk factors and ACS severity scores, the HbA1c/ApoA-1 ratio remained an independent predictor of all-cause mortality and MACEs in the ACS patients undergoing angiography.
Subject(s)
Acute Coronary Syndrome/blood , Apolipoprotein A-I/blood , Glycated Hemoglobin/analysis , Insulin Resistance , Acute Coronary Syndrome/diagnostic imaging , Acute Coronary Syndrome/mortality , Aged , Biomarkers/blood , Coronary Angiography , Female , Humans , Longitudinal Studies , Male , Middle Aged , Predictive Value of Tests , Prognosis , Retrospective Studies , Risk Assessment , Risk Factors , Time FactorsABSTRACT
The tunability of the longitudinal localized surface plasmon resonances (LSPRs) of metallic nanoarcs is demonstrated with key relationships identified between geometric parameters of the arcs and their resonances in the infrared. The wavelength of the LSPRs is tuned by the mid-arc length of the nanoarc. The ratio between the attenuation of the fundamental and second order LSPRs is governed by the nanoarc central angle. Beneficial for plasmonic enhancement of harmonic generation, these two resonances can be tuned independently to obtain octave intervals through the design of a non-uniform arc-width profile. Because the character of the fundamental LSPR mode in nanoarcs combines an electric and a magnetic dipole, plasmonic nanoarcs with tunable resonances can serve as versatile building blocks for chiroptical and nonlinear optical devices.
ABSTRACT
Tachycardia-induced atrial fibrosis is a hallmark of the structural remodeling of atrial fibrillation (AF). The mechanisms underlying tachycardia-induced atrial fibrosis remain unclear. In our previous study, we found that Smad7-downregulation promoted the development of atrial fibrosis in AF. Fibroblasts are enriched in microRNA-21 (miR-21), which contributes to the development of fibrosis and heart failure in the cardiovascular system. Our study was designed to test the hypothesis that miR-21 reinforces the TGF-ß1/Smad signaling pathway in AF-induced atrial fibrosis by down-regulating Smad7. Rapid atrial pacing (RAP, 1000 ppm) was applied to the left atrium of the rabbit heart to induce atrial fibrillation and fibrosis. qRT-PCR and northern blot analysis revealed that RAP caused a marked increase in the expression of miR-21. Transfection with a miR-21 inhibitor significantly increased the expression of Smad7, while the expression of collagen I/III significantly decreased. These changes were implicated in the AF-induced release of miR-21 and down-regulation of Smad7. Adult rat cardiac fibroblasts treated with TGF-ß1 showed increased miR-21 expression and decreased Smad7 expression. Pretreatment with a TGF-ß1 inhibitor reduced the TGF-ß1-induced up-regulation of miR-21. Pretreatment with pre-miR-21 and a miR-21 inhibitor significantly decreased and increased Smad7 expression, respectively. This result was negatively correlated with the expression of collagen I/III in fibroblasts. Moreover, the results of a luciferase activity assay suggest that Smad7 is a validated miR-21 target in CFs. Our results provide compelling evidence that the miR-21 specific degradation of Smad7 may decrease the inhibitory feedback regulation of TGF-ß1/Smad signaling and serves as a new insight of the mechanism of atrial fibrosis in atrial fibrillation.
Subject(s)
Atrial Fibrillation/metabolism , Fibroblasts/drug effects , MicroRNAs/metabolism , Signal Transduction/drug effects , Smad7 Protein/metabolism , Animals , Atrial Fibrillation/genetics , Collagen/metabolism , Disease Models, Animal , Down-Regulation , Fibrosis , Male , MicroRNAs/genetics , Myocardium/cytology , Rabbits , Rats , Rats, Sprague-Dawley , Smad7 Protein/genetics , Transforming Growth Factor beta1/pharmacology , Up-RegulationABSTRACT
Radiation-induced heart injury is one of the major side effects of radiotherapy for thoracic malignancies. Previous studies have shown that radiotherapy induced myocardial fibrosis and intensified myocardial remodeling. In this study, we investigated whether atorvastatin could inhibit radiation-induced heart fibrosis in Sprague-Dawley rats, which were randomly divided into six groups: control; radiation only; and four treatment groups receiving atorvastatin plus radiation (E1, E2, E3 and E4). All rats, except the control group, received local heart irradiation in 7 daily fractions of 3 Gy for a total of 21 Gy. Rats in groups E1 (10 mg/kg/day) and E2 (20 mg/kg/day) received atorvastatin and radiation treatment until week 12 after exposure. Rats in groups E3 (10 mg/kg/day) and E4 (20 mg/kg/day) received atorvastatin treatment from 3 months before irradiation to week 12 after irradiation. The expressions of TGF-ß1, Smad2, Smad3, fibronectin, ROCK I and p-Akt in heart tissues were evaluated using real-time PCR or Western blot analyses. Atorvastatin significantly reduced the expression of TGF-ß1, Smad3/P-Smad3, ROCK I and p-Akt in rats of the E1-E4 groups and in a dose-dependent manner. Fibronectin exhibited a similar pattern of expression changes. In addition, echocardiography showed that atorvastatin treatment can inhibit the increase of left ventricular end-diastolic dimension, left ventricular end-systolic diameter and left ventricular posterior wall thickness, and prevent the decrease of ejection fraction and fraction shortening in E1-E4 groups compared with the radiation only group. This study demonstrated that radiation exposure increased the expression of fibronectin in cardiac fibroblasts and induced cardiac fibrosis through activation of the TGF-ß1/Smad3, RhoA/ROCK, and PI3K/AKT signaling pathways. Statins ameliorated radiation-induced cardiac fibrosis in Sprague-Dawley rats. Our results suggest that atorvastatin is effective for the treatment of radiation-induced cardiac fibrosis, especially with longer and higher dose atorvastatin treatment, as demonstrated in experimental group E4.
Subject(s)
Atorvastatin/administration & dosage , Cardiotoxicity/prevention & control , Cardiotoxicity/physiopathology , Endomyocardial Fibrosis/prevention & control , Endomyocardial Fibrosis/physiopathology , Immunologic Factors/metabolism , Animals , Cardiotoxicity/etiology , Dose-Response Relationship, Drug , Endomyocardial Fibrosis/etiology , Male , Radiation Dosage , Radiation, Ionizing , Radiation-Protective Agents/administration & dosage , Rats , Rats, Sprague-Dawley , Treatment OutcomeABSTRACT
To solve the issues of costly planting of facility cultivation method and inferior efficacy than wild herbs of Dendrobium officinale, the cliff epiphytic cultivation method was studied. To research the growth, agronomic traits, yield, polysaccharide and alcohol-soluble extract contents were measured on the D. officinale from different water regulation and cliff slope gradients treatments. The results showed that D. officinale epiphytic at 85 degrees-90 degrees cliff and sprayed water 1-2 h x d(-1) at the growing season can get better growth and obtain high yield, and the morphology has no different from wild cliff D. officinale, even in the environments without shade. The contents of polysaccharide and alcohol-soluble extract are closely related to the physiological ages, but significantly higher than the facility cultivation. It is possible that environmental stresses benefit the accumulation of polysaccharides, alcohol-soluble extract and other efficient ingredients.
Subject(s)
Agriculture/methods , Dendrobium/growth & development , Dendrobium/chemistry , Drugs, Chinese Herbal/analysis , Polysaccharides/analysis , Water/analysisABSTRACT
PURPOSE: To investigate the association between the N-acetyltransferase 1 (NAT1) slow and rapid acetylation phenotypes with cancer risk based on a meta-analysis. METHODS: Previously published case-control studies were retrieved from PubMed, Embase, and Web of Science. Odds ratios (ORs) with 95% confidence intervals (CIs) were determined to assess the relationship between NAT1 polymorphisms and cancer risk. RESULTS: A total of 73 studies (24874 cases and 30226 controls) were included in this meta-analysis. No significant association was identified between NAT1 polymorphisms (slow acetylation versus rapid acetylation genotypes: OR = 0.978, 95% CI = 0.927-1.030, P < 0.001 for heterogeneity, I(2) = 45.5%) and cancer risk, whereas a significantly reduced risk of pancreatic cancer was identified in individuals with NAT1 slow acetylation genotype (OR = 0.856, 95% CI = 0.733-0.999, P =0.509 for heterogeneity, I(2) = 0). When the NAT1 slow acetylation genotype was analysed on the basis of stratified analyses of ethnicity, a significantly reduced risk of head and neck cancers was found among Asian (OR=0.281, 95% CI = 0.127-0.622). When the NAT1 slow acetylation genotype was analysed on the basis of stratified analyses of source of control, only significantly reduced risks of colorectal cancer (OR = 0.882, 95% CI = 0.798- 0.974, P = 0.212 for heterogeneity, I(2) = 22.9) and pancreatic cancer (OR=0.856, 95% CI = 0.733-0.999, P = 0.509 for heterogeneity, I(2) = 0) were found among hospital-based studies. CONCLUSIONS: No significant association between the NAT1 polymorphisms and the risk of cancer was found except for pancreatic cancer.
ABSTRACT
UNLABELLED: The aim of this study is to investigate the characteristics of Elekta delivery system for volumetric modulated arc therapy (VMAT). Five VMAT plans were delivered in service mode and dose rates, and speed of gantry and MLC leaves were analyzed by log files. Results showed that dose rates varied between 6 dose rates. Gantry and MLC leaf speed dynamically varied during delivery. CONCLUSION: The technique of VMAT requires linac to dynamically control more parameters, and these key dynamic variables during VMAT delivery can be checked by log files. Quality assurance procedure should be carried out for VMAT related parameter.