ABSTRACT
The properties of surface plasmons are notoriously dependent on the supporting materials system. However, new capabilities cannot be obtained until the technique of surface plasmon enabled by advanced two-dimensional materials is well understood. Herein, we present the experimental demonstration of surface plasmon polaritons (SPPs) supported by single-layered MXene flakes (Ti3C2Tx) coating on an optical microfiber and its application as an ammonia gas sensor. Enabled by its high controllability of chemical composition, unique atomistically thin layered structure, and metallic-level conductivity, MXene is capable of supporting not only plasmon resonances across a wide range of wavelengths but also a selective sensing mechanism through frequency modulation. Theoretical modeling and optics experiments reveal that, upon adsorbing ammonia molecules, the free electron motion at the interface between the SiO2 microfiber and the MXene coating is modulated (i.e., the modulation of the SPPs under applied light), thus inducing a variation in the evanescent field. Consequently, a wavelength shift is produced, effectively realizing a selective and highly sensitive ammonia sensor with a 100 ppm detection limit. The MXene supported SPPs open a promising path for the application of advanced optical techniques toward gas and chemical analysis.
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BACKGROUND: Drought severely limits sunflower production especially at the seedling stage. To investigate the response mechanism of sunflowers to drought stress, we utilized two genotypes of sunflower materials with different drought resistances as test materials. The physiological responses were investigated under well-watered (0 h) and drought-stressed conditions (24 h, 48 h, and 72 h). RESULTS: ANOVA revealed the greatest differences in physiological indices between 72 h of drought stress and 0 h of drought stress. Transcriptome analysis was performed after 72 h of drought stress. At 0 h, there were 7482 and 5627 differentially expressed genes (DEGs) in the leaves of K55 and K58, respectively, and 2150 and 2527 DEGs in the roots of K55 and K58, respectively. A total of 870 transcription factors (TFs) were identified among theDEGs, among which the high-abundance TF families included AP2/ERF, MYB, bHLH,and WRKY. Five modules were screened using weighted gene coexpressionnetwork analysis (WGCNA), three and two of which were positively and negatively, respectively, related to physiological traits. KEGG analysis revealedthat under drought stress, "photosynthesis", "carotenoid biosynthesis", "starch and sucrose metabolism", "ribosome", "carotenoid biosynthesis", "starch and sucrose metabolism", "protein phosphorylation" and "phytohormone signaling" are six important metabolic pathways involved in the response of sunflower to drought stress. Cytoscape software was used to visualize the three key modules, and the hub genes were screened. Finally, a total of 99 important candidate genes that may be associated with the drought response in sunflower plants were obtained, and the homology of these genes was compared with that in Arabidopsis thaliana. CONCLUSIONS: Taken together, our findings could lead to a better understanding of drought tolerance in sunflowers and facilitate the selection of drought-tolerant sunflower varieties.
Subject(s)
Arabidopsis , Helianthus , Humans , Transcriptome , Helianthus/genetics , Helianthus/metabolism , Drought Resistance , Gene Expression Profiling , Droughts , Arabidopsis/genetics , Starch/metabolism , Carotenoids/metabolism , Sucrose/metabolism , Stress, Physiological/genetics , Gene Expression Regulation, PlantABSTRACT
Modulating the solvation structure of hydrated zinc ions using organic additives stands as a pragmatic approach to suppress dendrite formation and corrosion on zinc metal anodes (ZMAs), thereby enhancing the rechargeability of aqueous Zn-ion batteries. However, fundamental screening principles for organic additives with diverse molecular structures remain elusive, especially for isomers with the same molecular formula. This study delves into the impact of three isomeric hexagonal alcohols (mannitol, sorbitol, and galactitol) as additives in adjusting Zn2+ solvation structural behaviors within ZnSO4 baseline electrolytes. Electrical measurements and molecular simulations reveal the specific molecular structure of mannitol, which features interweaving electron clouds between adjacent hydroxyl groups, achieving a high local electron cloud density. This phenomenon significantly enhances desolvation abilities, thus establishing a more stable anode/electrolyte interface chemistry. Even at 5 mA cm-2 for 2.5 mAh cm-2 capacity, Zn||Zn symmetric cells with mannitol-regulated electrolyte display an impressive 1170 h lifespan, far exceeding those with other isomer additives and is nearly tenfold longer than that with a pure ZnSO4 electrolyte (120 h). Rather than strictly adhering to focusing on chemical composition, this study with emphasis on optimizing molecular structure offers a promising untapped dimension to screen more efficient additives to enhance the reversibility of ZMAs.
ABSTRACT
Amyotrophic lateral sclerosis (ALS) is a rapidly progressive and fatal neurodegenerative disorder, characterized by selective loss of motor neurons (MNs). A number of causative genetic mutations underlie the disease, including mutations in the fused in sarcoma (FUS) gene, which can lead to both juvenile and late-onset ALS. Although ALS results from MN death, there is evidence that dysfunctional glial cells, including oligodendroglia, contribute to neurodegeneration. Here, we used human induced pluripotent stem cells (hiPSCs) with a R521H or a P525L mutation in FUS and their isogenic controls to generate oligodendrocyte progenitor cells (OPCs) by inducing SOX10 expression from a TET-On SOX10 cassette. Mutant and control iPSCs differentiated efficiently into OPCs. RNA sequencing identified a myelin sheath-related phenotype in mutant OPCs. Lipidomic studies demonstrated defects in myelin-related lipids, with a reduction of glycerophospholipids in mutant OPCs. Interestingly, FUSR521H OPCs displayed a decrease in the phosphatidylcholine/phosphatidylethanolamine ratio, known to be associated with maintaining membrane integrity. A proximity ligation assay further indicated that mitochondria-associated endoplasmic reticulum membranes (MAM) were diminished in both mutant FUS OPCs. Moreover, both mutant FUS OPCs displayed increased susceptibility to ER stress when exposed to thapsigargin, and exhibited impaired mitochondrial respiration and reduced Ca2+ signaling from ER Ca2+ stores. Taken together, these results demonstrate a pathological role of mutant FUS in OPCs, causing defects in lipid metabolism associated with MAM disruption manifested by impaired mitochondrial metabolism with increased susceptibility to ER stress and with suppressed physiological Ca2+ signaling. As such, further exploration of the role of oligodendrocyte dysfunction in the demise of MNs is crucial and will provide new insights into the complex cellular mechanisms underlying ALS.
Subject(s)
Amyotrophic Lateral Sclerosis , Induced Pluripotent Stem Cells , Humans , Amyotrophic Lateral Sclerosis/pathology , Induced Pluripotent Stem Cells/metabolism , Motor Neurons/metabolism , Mutation , Oligodendroglia/metabolism , RNA-Binding Protein FUS/genetics , RNA-Binding Protein FUS/metabolismABSTRACT
Over the past decades, spin qubits in silicon carbide (SiC) have emerged as promising platforms for a wide range of quantum technologies. The fluorescence intensity holds significant importance in the performance of quantum photonics, quantum information process, and sensitivity of quantum sensing. In this work, a dual-layer Au/SiO2 dielectric cavity is employed to enhance the fluorescence intensity of a shallow silicon vacancy ensemble in 4H-SiC. Experimental results demonstrate an effective fourfold augmentation in fluorescence counts at saturating laser power, corroborating our theoretical predictions. Based on this, we further investigate the influence of dielectric cavities on the contrast and linewidth of optically detected magnetic resonance (ODMR). There is a 1.6-fold improvement in magnetic field sensitivity. In spin echo experiments, coherence times remain constant regardless of the thickness of dielectric cavities. These experiments pave the way for broader applications of dielectric cavities in SiC-based quantum technologies.
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As an important cell factory, industrial yeast has been widely used for the production of compounds ranging from bulk chemicals to complex natural products. However, various adverse conditions including toxic products, extreme pH, and hyperosmosis etc., severely restrict microbial growth and metabolic performance, limiting the fermentation efficiency and diminishing its competitiveness. Therefore, enhancing the tolerance and robustness of yeasts is critical to ensure reliable and sustainable production of metabolites in complex industrial production processes. In this review, we provide a comprehensive review of various strategies for improving the tolerance of yeast cells, including random mutagenesis, system metabolic engineering, and material-mediated immobilization cell technology. It is expected that this review will provide a new perspective to realize the response and intelligent regulation of yeast cells to environmental stresses.
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Tectona grandis Linn, commonly known as teak, is traditionally used to treat a range of diseases, including the common cold, headaches, bronchitis, scabies, diabetes, inflammation, and others. The present study was conducted with the purpose of isolating and identifying the active compounds in T. grandis leaf against a panel of Vibrio spp., which may induce vibriosis in shrimp, using bioassay-guided purification. The antimicrobial activity was assessed using the microdilution method, followed by the brine shrimp lethality assay to determine toxicity. Following an initial screening with a number of different solvents, it was established that the acetone extract was the most effective. The acetone extract was then exposed to silica gel chromatography followed by reversed-phase HPLC and further UHPLC-orbitrap-ion trap mass spectrometry to identify the active compounds. Three compounds called 1-hydroxy-2,6,8-trimethoxy-9,10-anthraquinone, deoxyanserinone B, and khatmiamycin were identified with substantial anti-microbial action against V. parahaemolyticus, V. alginolyticus, V. harveyi, V. anguillarum, and V. vulnificus. The IC50 values of the three compounds viz. 1-hydroxy-2,6,8-trimethoxy-9,10-anthraquinone, deoxyanserinone B, and khatmiamycin varied between 2 and 28, 7 and 38, and 7 and 56 µg/mL, respectively, which are as good as the standard antibiotics such as amoxicillin and others. The in vivo toxicity test revealed that the compounds were non-toxic to shrimp. The results of the study suggest that T. grandis leaf can be used as a source of bioactive compounds to treat Vibrio species in shrimp farming.
Subject(s)
Anti-Bacterial Agents , Artemia , Biological Assay , Microbial Sensitivity Tests , Plant Extracts , Plant Leaves , Vibrio , Animals , Vibrio/drug effects , Plant Extracts/pharmacology , Plant Extracts/chemistry , Plant Leaves/chemistry , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/isolation & purification , Artemia/drug effects , Combretaceae/chemistry , Chemical FractionationABSTRACT
INTRODUCTION: Cisplatin (DDP) is the commonest chemo drug in lung adenocarcinoma (LUAD) treatment, and DDP resistance is a significant barrier to therapeutic therapy. This study attempted to elucidate the impact of PDK1 on DDP resistance in LUAD and its mechanism. METHODS: Bioinformatics analysis was used to determine the expression and enriched pathways of PDK1 in LUAD tissue. Subsequently, E2F8, the upstream transcription factor of PDK1 was predicted, and the binding relationship between the two was analyzed using dual-luciferase and ChIP experiments. PDK1 and E2F8 levels in LUAD tissues and cells were detected via qPCR. Cell viability, proliferation, and apoptosis levels were assayed by CCK-8, EdU, and flow cytometry experiments, respectively. Comet assay was used to assess DNA damage, and immunofluorescence was used to assess the expression of γ-H2AX. NHEJ reporter assay was to assess DNA repair efficiency. Western blot tested levels of DNA damage repair (DDR)-related proteins. Immunohistochemistry assessed the expression of relevant genes. Finally, an animal model was constructed to investigate the influence of PDK1 expression on LUAD growth. RESULTS: PDK1 was found to be upregulated in LUAD and enhanced DDP resistance by mediating DDR. E2F8 was identified as an upstream transcription factor of PDK1 and was highly expressed in LUAD. Rescue experiments presented that knocking down E2F8 could weaken the promotion of PDK1 overexpression on DDR-mediated DDP resistance in LUAD. In vivo experiments showed that knocking down PDK1 plus DDP significantly reduced the growth of xenograft tumors. CONCLUSION: Our results indicated that the E2F8/PDK1 axis mediated DDR to promote DDP resistance in LUAD. Our findings lead to an improved treatment strategy after drug resistance.
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Urbanization can either directly occupy forests or indirectly lead to forest loss elsewhere through cultivated land displacement, resulting in further forest fragmentation and ecosystem service (ES) loss. However, the effects of urban expansion on forest area and ESs are unknown, and this is especially true for indirect effects. Taking Zhejiang Province, China, a typical deforested province, as an example, this study quantified the direct and indirect effects of urban expansion on forest area and five ESs (timber yield, water yield, carbon sequestration, soil conservation, and biodiversity) from 2000 to 2020, explored the relationship between forest structure (forest proportion, mean patch area, edge density, and mean euclidean nearest neighbor distance) change and ESs, and revealed the telecoupling of urban expansion and forest loss and cascade effects among urbanization, deforestation, forest structure, and ESs. The results indicated that the indirect forest loss (4.30%-6.15%) caused by cultivated land displacement due to urban expansion was larger than the direct forest loss (2.42%). Urban expansion has a greater negative impact on carbon sequestration (6.40%-8.20%), water yield (6.08%-7.78%), and biodiversity (5.79%-7.44%) than on timber yield (4.77%-6.17%) and soil conservation (4.43%-5.77%). The indirect forest ES loss was approximately 2.83-4.34 times greater than the direct forest ES loss. Most forest ESs showed a nonlinear significant positive correlation with changes in forest proportion and mean patch area and a significant nonlinear negative correlation with changes in edge density and mean Euclidean nearest neighbor distance (p < 0.05). There is telecoupling between urban expansion in one region and forest ES loss in other distant regions. This study contributes to guiding sustainable forest conservation and management globally.
Subject(s)
Conservation of Natural Resources , Ecosystem , Forests , Soil , China , WaterABSTRACT
As a multifunctional adipokine, chemerin plays a crucial role in various pathophysiological processes through endocrine and paracrine manner. It can bind to three known receptors (ChemR23, GPR1 and CCRL2) and participate in energy metabolism, glucose and lipid metabolism, and inflammation, especially in metabolic diseases. Polycystic ovary syndrome (PCOS) is one of the most common endocrine diseases, which seriously affects the normal life of women of childbearing age. Patients with PCOS have significantly increased serum levels of chemerin and high expression of chemerin in their ovaries. More and more studies have shown that chemerin is involved in the occurrence and development of PCOS by affecting obesity, insulin resistance, hyperandrogenism, oxidative stress and inflammatory response. This article mainly reviews the production, subtypes, function and receptors of chemerin protein, summarizes and discusses the research status of chemerin protein in PCOS from the perspectives of metabolism, reproduction and inflammation, and provides theoretical basis and reference for the clinical diagnosis and treatment of PCOS.
Subject(s)
Chemokines , Intercellular Signaling Peptides and Proteins , Polycystic Ovary Syndrome , Polycystic Ovary Syndrome/metabolism , Humans , Chemokines/metabolism , Female , Intercellular Signaling Peptides and Proteins/metabolism , Receptors, Chemokine/metabolism , Insulin Resistance , Animals , Receptors, G-Protein-Coupled/metabolism , Chemotactic Factors/metabolismABSTRACT
D-glucuronic acid is a kind of glucose derivative, which has excellent properties such as anti-oxidation, treatment of liver disease and hyperlipidemia, and has been widely used in medicine, cosmetics, food and other fields. The traditional production methods of D-glucuronic acid mainly include natural extraction and chemical synthesis, which can no longer meet the growing market demand. The production of D-glucuronic acid by biocatalysis has become a promising alternative method because of its high efficiency and environmental friendliness. This review describes different production methods of D-glucuronic acid, including single enzyme catalysis, multi-enzyme cascade, whole cell catalysis and co-culture, as well as the intervention of some special catalysts. In addition, some feasible enzyme engineering strategies are provided, including the application of enzyme immobilized scaffold, enzyme mutation and high-throughput screening, which provide good ideas for the research of D-glucuronic acid biocatalysis.
Subject(s)
Engineering , Biocatalysis , Catalysis , Coculture Techniques , Glucuronic AcidABSTRACT
Sprouting of mossy fibers, one of the most consistent findings in tissue from patients with mesial temporal lobe epilepsy, exhibits several uncommon axonal growth features and has been considered a paradigmatic example of circuit plasticity that occurs in the adult brain. Clarifying the mechanisms responsible may provide new insight into epileptogenesis as well as axon misguidance in the central nervous system. Methyl-CpG-binding protein 2 (MeCP2) binds to methylated genomic DNA to regulate a range of physiological functions implicated in neuronal development and adult synaptic plasticity. However, exploring the potential role of MeCP2 in the documented misguidance of axons in the dentate gyrus has not yet been attempted. In this study, a status epilepticus-induced decrease of neuronal MeCP2 was observed in the dentate gyrus (DG). An essential regulatory role of MeCP2 in the development of functional mossy fiber sprouting (MFS) was confirmed through stereotaxic injection of a recombinant adeno-associated virus (AAV) to up- or down-regulate MeCP2 in the dentate neurons. Chromatin immunoprecipitation sequencing (ChIP-seq) was performed to identify the binding profile of native MeCP2 using micro-dissected dentate tissues. In both dentate tissues and HT22 cell lines, we demonstrated that MeCP2 could act as a transcription repressor on miR-682 with the involvement of the DNA methylation mechanism. Further, we found that miR-682 could bind to mRNA of phosphatase and tensin homolog (PTEN) in a sequence specific manner, thus leading to the suppression of PTEN and excessive activation of mTOR. This study therefore presents a novel epigenetic mechanism by identifying MeCP2/miR-682/PTEN/mTOR as an essential signal pathway in regulating the formation of MFS in the temporal lobe epileptic (TLE) mice. SIGNIFICANCE STATEMENT: Understanding the mechanisms that regulate axon guidance is important for a better comprehension of neural disorders. Sprouting of mossy fibers, one of the most consistent findings in patients with mesial temporal lobe epilepsy, has been considered a paradigmatic example of circuit plasticity in the adult brain. Although abnormal regulation of DNA methylation has been observed in both experimental rodents and humans with epilepsy, the potential role of DNA methylation in this well-documented example of sprouting of dentate axon remains elusive. This study demonstrates an essential role of methyl-CpG-binding protein 2 in the formation of mossy fiber sprouting. The underlying signal pathway has been also identified. The data hence provide new insight into epileptogenesis as well as axon misguidance in the central nervous system.
Subject(s)
Epilepsy, Temporal Lobe , Epilepsy , MicroRNAs , Animals , Humans , Mice , Dentate Gyrus/metabolism , Epilepsy, Temporal Lobe/metabolism , Methyl-CpG-Binding Protein 2/genetics , Methyl-CpG-Binding Protein 2/metabolism , MicroRNAs/metabolism , Mossy Fibers, Hippocampal , TOR Serine-Threonine Kinases/metabolismABSTRACT
The bulbs of Allium sativum known as garlic are widely used as food or seasoning. In China they have been used as a traditional Chinese medicine (TCM) since ancient times for the treatment of scabies, tuberculosis, pertussis, diarrhea and dysentery. A. sativum has reportedly shown platelet aggregation inhibition and has been used in the treatment of cardiovascular diseases. However, there are only few studies focussing on the aerial parts, which are normally discarded during harvest. In this study, two new ionone glycosides, dasuanxinosides D and E (1, 2: ), are isolated from the aerial parts together with 13 known compounds including alkanes derivatives and alkyl glycosides (3â-â15: ), which are reported for the first time from this plant. Their structures are identified by extensive NMR and HRMS analyses. The isolated compounds are evaluated for their inhibitory effect on adenosine diphosphate (ADP)-induced platelet aggregation in vitro.
Subject(s)
Garlic , Garlic/chemistry , Norisoprenoids/pharmacology , Glycosides/pharmacology , Platelet Aggregation , Plant Components, AerialABSTRACT
In this study, a novel peroxydisulfate (PDS) activator (CF-nZVI-JE) was prepared via in-situ loading nano zero-valent iron (nZVI) on Juncus effusus (JE) followed with wrapping a layer of cellulose film (CF). The CF-nZVI-JE had the same 3D structure as the JE, being easy to separate from aqueous solution. The loaded nZVI existed single nanoparticles with a size of 60-100 nm except chain-type agglomeration of nanoparticles due to the stabilization of JE fibers. The activation performance of the CF-nZVI-JE for PDS was evaluated with Rhodamine B (Rh B) as a representative pollutant. Under the optimal activating conditions, the degradation rate of Rh B reached 99% within 30 min in the CF-nZVI-JE/PDS system. After five cycles, the degradation rate of Rh B was still over 85%, suggesting that the CF-nZVI-JE had good reusability. More interestingly, SO4·- and ·OH radicals were simultaneously detected in the CF-nZVI-JE/PDS system, but only SO4·- existed in the JE-ZVI/PDS system, suggesting the different activation mechanism. Meanwhile, the introduction of CF not only facilitated to the mineralization of Rh B but also significantly reduced the release amount of iron ions. Hence, the CF-nZVI-JE can be employed as a promising PDS activator for the treatment of organic wastewater.
Subject(s)
Iron , Water Pollutants, Chemical , Iron/chemistry , Rhodamines , Wastewater , Water , Water Pollutants, Chemical/chemistryABSTRACT
As one of the most aggressive malignancies, non-small cell lung carcinoma (NSCLC) has high risks of death. It has been demonstrated that circRNAs accelerate NSCLC progression, but the underlying molecular mechanisms of circRNAs in NSCLC were still obscure. In the first place, the circRNA microarray of NSCLC was investigated in this study, and hsa_circ_0008003 (circ-0008003) was chosen as the research object. Then, it was unveiled that the expression of circ-0008003 examined via qRT-PCR was elevated in tumour tissues relative to the non-tumour tissues, which was associated with TNM stage and lymphatic metastasis in NSCLC. Additionally, the prognosis of NSCLC patients with high circ-0008003 level was poor. Besides, circ-0008003 silencing dampened the invasion and proliferation of NSCLC cells. Next, according to the mechanistic studies, circ-0008003 functioned as a ceRNA of ZNF281 in NSCLC by acting as the endogenous sponge for miR-488, which was proved to be a tumour suppressor in NSCLC. Additionally, ZNF281 overexpression and miR-488 suppression recovered the influences of repressed circ-0008003 on NSCLC cellular processes. It was validated in this research that circ-0008003 triggered tumour formation in NSCLC, which was adjusted via miR-488/ZNF281 axis, casting a novel light on the resultful target for treating NSCLC and predicting the prognosis.
Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , MicroRNAs , Carcinogenesis/genetics , Carcinoma, Non-Small-Cell Lung/pathology , Cell Proliferation/genetics , Cell Transformation, Neoplastic , Humans , Lung Neoplasms/pathology , MicroRNAs/genetics , MicroRNAs/metabolism , RNA, Circular/genetics , Repressor ProteinsABSTRACT
Poor oxygen diffusion at multiphase interfaces in an air cathode suppresses the energy densities of zinc-air batteries (ZABs). Developing effective strategies to tackle the issue is of great significance for overcoming the performance bottleneck. Herein, inspired by the bionics of diving flies, a polytetrafluoroethylene layer was coated on the surfaces of Co3 O4 nanosheets (NSs) grown on carbon cloth (CC) to create a hydrophobic surface to enable the formation of more three-phase reaction interfaces and promoted oxygen diffusion, rendering the hydrophobic-Co3 O4 NSs/CC electrode a higher limiting current density (214â mA cm-2 at 0.3â V) than that (10â mA cm-2 ) of untreated-Co3 O4 NSs/CC electrode. Consequently, the assembled ZAB employing hydrophobic-Co3 O4 NSs/CC cathode acquired a higher power density (171â mW cm-2 ) than that (102â mW cm-2 ) utilizing untreated-Co3 O4 NSs/CC cathode, proving the enhanced interfacial reaction kinetics on air cathode benefiting from the hydrophobization engineering.
ABSTRACT
OBJECTIVES: This study was conducted to investigate whether percutaneous closure of ruptured sinus of Valsalva aneurysm (SVA) is as safe and effective as surgery repair. BACKGROUND: Percutaneous closure of ruptured SVA has been becoming an alternative to the traditional surgical repair recently. The reports regarding direct comparison of these two treatment options are scarce. METHODS: The medical records from the institutional database were retrospectively analyzed. A total of 134 patients were reviewed, including 26 patients undergoing percutaneous closure and 108 patients being treated surgically. To reduce the potential bias, 32 patients from Surgical Repair group were selected by propensity score matching. RESULTS: All the ruptured SVAs were successfully closed in each group. No severe procedure-related complications were found in the perioperative period. After matching, there were no significant differences in the baseline clinical characteristics. The median postoperative hospital stays of Matched group were significantly longer than that of Percutaneous Closure group (7 days vs. 1 day, p < .001). Aortic regurgitation, residual shunt and recurrence of SVAs were common complications in both Percutaneous Closure group and Surgical Repair group. CONCLUSIONS: The appropriately selected patients with ruptured SVA could be treated by percutaneous closure with an acceptable risk of short-term complications. Though surgical repair remains the main treatment option for ruptured SVAs, percutaneous closure could be considered in patients with a small-size rupture and no associated cardiac abnormalities.
Subject(s)
Aortic Aneurysm , Aortic Rupture , Sinus of Valsalva , Aortic Aneurysm/diagnostic imaging , Aortic Aneurysm/surgery , Aortic Rupture/diagnostic imaging , Aortic Rupture/surgery , Humans , Retrospective Studies , Sinus of Valsalva/diagnostic imaging , Sinus of Valsalva/surgery , Treatment OutcomeABSTRACT
The roots of Fissistigma oldhamii (FO) are widely used as medicine with the effect of dispelling wind and dampness, promoting blood circulation and relieving pains, and its fruits are considered delicious. However, Hakka people always utilize its above-ground parts as a famous folk medicine, Xiangteng, with significant differences from literatures. Studies of chemical composition showed there were multiple aristolactams that possessed high nephrotoxicity, pending evaluation research about their distribution in FO. In this study, a sensitive, selective, rapid and reliable method was established to comparatively perform qualitative and semi-quantitative analysis of the constituents in roots, stems, leaves, fruits and insect galls, using an Ultra-High-Performance Liquid Chromatography coupled with Hybrid Quadrupole Orbitrap Mass Spectrometry (UPLC-Q-Exactive Orbitrap MS, or Q-Exactive for short). To make more accurate identification and comparison of FO chemicals, all MS data were aligned and screened by XCMS, then their structures were elucidated according to MSn ion fragments between the detected and standards, published ones or these generated by MS fragmenter. A total of 79 compounds were identified, including 33 alkaloids, 29 flavonoids, 11 phenylpropanoids, etc. There were 54 common components in all five parts, while another 25 components were just detected in some parts. Six toxic aristolactams were detected in this experiment, including aristolactam AII, AIIIa, BII, BIII, FI and FII, of which the relative contents in above-ground stems were much higher than roots. Meanwhile, multivariate statistical analysis was performed and showed significant differences both in type and content of the ingredients within all FO parts. The results implied that above-ground FO parts should be carefully valued for oral administration and eating fruits. This study demonstrated that the high-resolution mass spectrometry coupled with multivariate statistical methods was a powerful tool in compound analysis of complicated herbal extracts, and the results provide the basis for its further application, scientific development of quality standard and utilization.
Subject(s)
Annonaceae/chemistry , Drugs, Chinese Herbal/chemistry , Plant Leaves/chemistry , Plant Roots/chemistry , Alkaloids/chemistry , Alkaloids/therapeutic use , Chromatography, High Pressure Liquid , Drugs, Chinese Herbal/therapeutic use , Humans , Tandem Mass SpectrometryABSTRACT
The widely application of positioning technology has made collecting the movement of people feasible for knowledge-based decision. Data in its original form often contain sensitive attributes and publishing such data will leak individuals' privacy. Especially, a privacy threat occurs when an attacker can link a record to a specific individual based on some known partial information. Therefore, maintaining privacy in the published data is a critical problem. To prevent record linkage, attribute linkage, and similarity attacks based on the background knowledge of trajectory data, we propose a data privacy preservation with enhanced l-diversity. First, we determine those critical spatial-temporal sequences which are more likely to cause privacy leakage. Then, we perturb these sequences by adding or deleting some spatial-temporal points while ensuring the published data satisfy our ( L , α , ß )-privacy, an enhanced privacy model from l-diversity. Our experiments on both synthetic and real-life datasets suggest that our proposed scheme can achieve better privacy while still ensuring high utility, compared with existing privacy preservation schemes on trajectory.
ABSTRACT
The modulation effect has been widely investigated to tune the electronic state of single-atomic M-N-C catalysts to enhance the activity of oxygen reduction reaction (ORR). However, the in-depth study of modulation effect is rarely reported for the isolated dual-atomic metal sites. Now, the catalytic activities of Fe-N4 moiety can be enhanced by the adjacent Pt-N4 moiety through the modulation effect, in which the Pt-N4 acts as the modulator to tune the 3d electronic orbitals of Fe-N4 active site and optimize ORR activity. Inspired by this principle, we design and synthesize the electrocatalyst that comprises isolated Fe-N4 /Pt-N4 moieties dispersed in the nitrogen-doped carbon matrix (Fe-N4 /Pt-N4 @NC) and exhibits a half-wave potential of 0.93â V vs. RHE and negligible activity degradation (ΔE1/2 =8â mV) after 10000 cycles in 0.1â M KOH. We also demonstrate that the modulation effect is not effective for optimizing the ORR performances of Co-N4 /Pt-N4 and Mn-N4 /Pt-N4 systems.