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A quantum anomalous Hall (QAH) state is a two-dimensional topological insulating state that has a quantized Hall resistance of h/(Ce2) and vanishing longitudinal resistance under zero magnetic field (where h is the Planck constant, e is the elementary charge, and the Chern number C is an integer)1,2. The QAH effect has been realized in magnetic topological insulators3-9 and magic-angle twisted bilayer graphene10,11. However, the QAH effect at zero magnetic field has so far been realized only for C = 1. Here we realize a well quantized QAH effect with tunable Chern number (up to C = 5) in multilayer structures consisting of alternating magnetic and undoped topological insulator layers, fabricated using molecular beam epitaxy. The Chern number of these QAH insulators is determined by the number of undoped topological insulator layers in the multilayer structure. Moreover, we demonstrate that the Chern number of a given multilayer structure can be tuned by varying either the magnetic doping concentration in the magnetic topological insulator layers or the thickness of the interior magnetic topological insulator layer. We develop a theoretical model to explain our experimental observations and establish phase diagrams for QAH insulators with high, tunable Chern number. The realization of such insulators facilitates the application of dissipationless chiral edge currents in energy-efficient electronic devices, and opens up opportunities for developing multi-channel quantum computing and higher-capacity chiral circuit interconnects.
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The capsule-associated protein 10 gene (CAP10) is indispensable due to its involvement in pod formation and virulence maintenance in Cryptococcus neoformans. The function of the CAP10 gene in nematode-predatory fungi remains unreported. As a typical nematode-trapping fungus, Dactylellina haptotyla efficiently captures nematodes using adhesive knobs, which has potential applications in the biological control of plant-parasitic nematodes. In this study, we investigated the function of DHXT1 (a CAP10 homologous protein) in D. haptotyla-nematode interactions based on the disruption and overexpression of DHXT1, phenotypic analysis and metabolomic analysis. As a result, it was shown that the disruption of the DHXT1 gene causes a marked decrease in the number of adhesive knobs, and on the contrary, the overexpression of the DHXT1 gene causes a substantial increase in the number of adhesive knobs. Interestingly, the variety of metabolites increased with the disruption of the DHXT1 and decreased with the overexpression of the DHXT1 gene. The results suggest that DHXT1 effects pathogenicity through its involvement in adhesive knobs' formation and metabolite synthesis and serves as a key virulence factor in D. haptotyla.
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Proteínas Fúngicas , Fatores de Virulência , Fatores de Virulência/metabolismo , Fatores de Virulência/genética , Animais , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Virulência , Doenças das Plantas/parasitologia , Doenças das Plantas/microbiologiaRESUMO
Exploring effective sensors for detecting possible hazards in a water system are greatly significant. This work proposed a strategy for stable and effective bifunctional sensors via incorporating hourglass-type phosphomolybdates into metal-organic fragments to construct a high-dimensional framework. Two hourglass-type phosphomolybdate-based electrochemical sensors toward heavy metal ion Cr(VI) and tetracycline (TC) detection were designed with the formula [CoII2(H2O)4NaI2][CoII(Hbpe)][NaI(bpe)1.5]{CoII[PV4MoV6O31H6]2}·9H2O (1) and [CoII(H2O)4NaI3][CoII(Hbpe)][CoII(bpe)]{CoII[PV4MoV6O31H6]2}·9H2O (2) [bpe = 1,2-di(4-pyridyl)ethylene]. Structural analysis showed that hybrids 1 and 2 possess three-dimensional POM-supported network features with favorable stability and exhibit reversible redox properties. Experiments found that this kind of hybrids as efficient sensors have excellent electrochemical performance toward Cr(VI) detection with high sensitivities of 0.111 µA·µM-1 for 1 and 0.141 µA·µM-1 for 2, fast response time of 1 s, and low detection limits of 30 nM for 1 and 27 nM for 2, which far meet the standard of WHO for drinking water. Moreover, hybrids 1-2 also exhibit fast responses to TC detection with sensitivities of 0.0073 and 0.022 µA·mM-1 and detection limits of 0.426 and 0.084 mM. This work offers a novel strategy for the purposeful design of efficient POM-based electrochemical sensors for accurate determination of contaminants in a practical water system.
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Cromo , Água , Cromo/química , Molibdênio , Ácidos Fosfóricos , TetraciclinaRESUMO
Punica granatum L. (Punicaceae) is a popular fruit all over the world. Owning to its enriched polyphenols, P. granatum has been widely used in treating inflammation-related diseases, such as cardiovascular diseases and cancer. Twenty polyphenols, containing nine unreported ones, named punicagranins A-I (1-9), along with eleven known isolates (10-20), were obtained from the peels. Their detailed structures were elucidated based on UV, IR, NMR, MS, optical rotation, ECD analyses and chemical evidence. The potential anti-inflammatory activities of all polyphenols were examined on a lipopolysaccharide (LPS)-induced inflammatory macrophages model, which indicated that enhancing nitric oxide (NO) production in response to inflammation stimulated in RAW 264.7 cells was controlled by compounds 1, 3, 5-8, 10, 11, 14 and 16-20 in a concentration-dependent manner. The investigation of structure-activity relationships for tannins 6-8 and 12-20 suggested that HHDP, flavogallonyl and/or gallagyl were key groups for NO production inhibitory activity. Western blotting indicated that compounds 6-8 could down-regulate the phosphorylation levels of proteins p38 MAPK, IKKα/ß, IκBα and NF-κB p65 as well as inhibit the levels of inflammation-related cytokines and mediators, such as IL-6, TNF-α, iNOS and COX-2, at the concentration of 30 µM. In conclusion, polyphenols are proposed to be the potential anti-inflammatory active ingredients in P. granatum peels, and their molecular mechanism is likely related to the regulation of the p38 MAPK and NF-κB signaling pathways.
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Lythraceae , Punica granatum , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Citocinas/metabolismo , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Polifenóis/farmacologia , Polifenóis/uso terapêutico , Células RAW 264.7 , Transdução de Sinais , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismoRESUMO
Leukemia inhibitory factor receptor (LIFR) has been documented as a cancer promoter and to be present at high levels in various types of tumor tissues. In our search for molecules prognostic of colorectal cancer (CRC), we found high levels of LIFR in CRC tissue samples. Further analyses revealed that LIFR was indeed prognostic of CRC patient survival, and was associated with tumor size, lymphatic metastasis and stages. LIFR was found to promote tumor growth, metastasis and angiogenesis both in vitro and in vivo. High levels of LIFR in CRC facilitated proliferation and migration of endothelial cells, resulting in an increase in angiogenic activity. Moreover, interleukin 8 (IL-8) was found to play a role in the LIFR induced angiogenesis. IL-8 levels were correlated with LIFR levels in CRC tissues, whereas depletion of IL-8 led to a reduced angiogenic activity of LIFR in CRC cells. In addition, LIFR increased phosphorylation level of Erk, which regulates il-8 transcription. We conclude that LIFR is possibly a valuable prognostic marker for CRC. Our results also implicate a mechanism by which LIFR regulates tumor angiogenesis through Erk/IL-8 pathway, and that LIFR could be a potential therapeutic target for CRC.
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Neoplasias Colorretais/irrigação sanguínea , Células Endoteliais/patologia , Interleucina-8/metabolismo , Subunidade alfa de Receptor de Fator Inibidor de Leucemia/metabolismo , Neovascularização Patológica/patologia , Idoso , Animais , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Regulação para Baixo , Feminino , Seguimentos , Células Endoteliais da Veia Umbilical Humana , Humanos , Interleucina-8/genética , Subunidade alfa de Receptor de Fator Inibidor de Leucemia/genética , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Neovascularização Patológica/mortalidade , Prognóstico , RNA Interferente Pequeno/metabolismo , Regulação para Cima , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
The study aims to establish a preliminary environmental assessment of a quinaldine-based LOHC system composed of hydrogen-lean, partially hydrogenated, and fully hydrogenated forms. We examined their toxicity toward the soil bacteria Arthrobacter globiformis and the Collembola Folsomia candida in two exposure scenarios, with and without soil, to address differences in the bioavailability of the compounds. In both scenarios, no or only slight toxicity toward soil bacteria was observed at the highest test concentration (EC50 > 3397 µmol L-1 and >4892 µmol kg-1 dry weight soil). The effects of the three quinaldines on F. candida in soil were similar, with EC50 values ranging from 2119 to 2559 µmol kg-1 dry weight soil based on nominal concentrations. Additionally, corrected pore-water-concentration-based EC50 values were calculated by equilibrium partitioning using soil/pore-water distribution coefficients. The tests without soil (simulating pore-water exposure) revealed higher toxicity, with LC50 values between 78.3 and 161.6 µmol L-1 and deformation of the protective cuticle. These results assign the compounds to the category "harmful to soil organisms". Potential risks toward the soil environment of the test compounds are discussed on the basis of predicted no-effect concentrations.
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Arthrobacter , Artrópodes , Quinaldinas , Poluentes do Solo , Animais , Hidrogênio , Reprodução , SoloRESUMO
Recently, we reported that Ilexgenin A exhibits anti-cancer activities and induces cell arrest. Here, we investigated the effect of Ilexgenin A on the inflammation, angiogenesis and tumor growth of hepatocellular carcinoma (HCC). Our current study revealed that Ilexgenin A significantly inhibited the inflammatory cytokines TNF-α and IL-6 levels and downregulated pro-angiogenic factor VEGF production and transcription in HepG2 cells. The underlying mechanism for Ilexgenin A effects appears to be through inhibiting STAT3 and PI3K pathways. Furthermore, we found that not only Ilexgenin A inhibited STAT3 and PI3K pathways in HepG2 cells but also blocked these signaling pathways in HUVECs. Most importantly, by employing two HCC xenografts models - HepG2 and H22, we showed that Ilexgenin A reduced tumor growth and exhibited synergy effect with Sorafenib. ELISA assay, histological analysis and immunohistochemistry examination revealed that the expression of VEGF and MVD was significantly decreased after the treatment with Ilexgenin A and the combination. Moreover, Ilexgenin A could enhance caspase-3/7 activity in vitro and transmission electron microscope indicated that the combination induced evident apoptosis of tumor cells and caused the structural changes of mitochondria in vivo. Although no apparent adverse effects occurred during the treatment period, Sorafenib monotherapy elicited hepatotoxicity for specific expression in the increased level of AST and the ratio of AST/ALT. However, the combination could remedy this adverse effect. In conclusion, the results described in the present study identifies Ilexgenin A as a promising therapeutic candidate that modulates inflammation, angiogenesis, and HCC growth.
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Inibidores da Angiogênese/farmacologia , Anti-Inflamatórios/farmacologia , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Niacinamida/análogos & derivados , Compostos de Fenilureia/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Fator de Transcrição STAT3/metabolismo , Triterpenos/farmacologia , Animais , Proliferação de Células/efeitos dos fármacos , Sinergismo Farmacológico , Células Hep G2 , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Niacinamida/farmacologia , Fosforilação , SorafenibeRESUMO
RNA has received more attention in the field of forensic medicine and the development of the new biological markers based on RNA shows great significance in the analysis of complex cases. circular RNA (circRNA) is a kind of non-coding RNA which is widely reported recently. Although the regulatory mechanisms of generation and expression are not fully clear, the existing research indicates that circRNA has important biological functions. CircRNA has a cell-type-specific expression with great stability and a high expression level, which makes it meaningful in forensic applications potentially. In this paper, the research progress, the generation and regulation of circRNA as well as its biological characteristics and functions are summarized, which will provide references for related studies and forensic applications.
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Ciências Forenses , RNA , Humanos , RNA CircularRESUMO
The clustered regularly interspaced short palindromic repeats and their associated proteins (CRISPR-Cas) system widely occurs in prokaryotic organisms to recognize and destruct genetic invaders. Systematic collation and characterization of endogenous CRISPR-Cas systems are conducive to our understanding and potential utilization of this natural genetic machinery. In this study, we screened 39 complete and 692 incomplete genomes of myxobacteria using a combined strategy to dispose of the abridged genome information and revealed at least 19 CRISPR-Cas subtypes, which were distributed with a taxonomic difference and often lost stochastically in intraspecies strains. The cas genes in each subtype were evolutionarily clustered but deeply separated, while most of the CRISPRs were divided into four types based on the motif characteristics of repeat sequences. The spacers recorded in myxobacterial CRISPRs were in high G+C content, matching lots of phages, tiny amounts of plasmids, and, surprisingly, massive organismic genomes. We experimentally demonstrated the immune and self-target immune activities of three endogenous systems in Myxococcus xanthus DK1622 against artificial genetic invaders and revealed the microhomology-mediated end-joining mechanism for the immunity-induced DNA repair but not homology-directed repair. The panoramic view and immune activities imply potential omnipotent immune functions and applications of the endogenous CRISPR-Cas machinery. IMPORTANCE: Serving as an adaptive immune system, clustered regularly interspaced short palindromic repeats and their associated proteins (CRISPR-Cas) empower prokaryotes to fend off the intrusion of external genetic materials. Myxobacteria are a collective of swarming Gram-stain-negative predatory bacteria distinguished by intricate multicellular social behavior. An in-depth analysis of their intrinsic CRISPR-Cas systems is beneficial for our understanding of the survival strategies employed by host cells within their environmental niches. Moreover, the experimental findings presented in this study not only suggest the robust immune functions of CRISPR-Cas in myxobacteria but also their potential applications.
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Sistemas CRISPR-Cas , Genoma Bacteriano , Myxococcales , Sistemas CRISPR-Cas/genética , Genoma Bacteriano/genética , Myxococcales/genética , Filogenia , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genéticaRESUMO
We conducted a comparative analysis to unveil the divergence among venoms from a subset of Old World habu snakes (Protobothrops) in terms of venomic profiles and toxicological and enzymatic activities. A total of 14 protein families were identified in the venoms from these habu snakes, and 11 of them were shared among these venoms. The venoms of five adult habu snakes were overwhelmingly dominated by SVMP (32.56 ± 13.94%), PLA2 (22.93 ± 9.26%), and SVSP (16.27 ± 4.79%), with a total abundance of over 65%, while the subadult P. mangshanensis had an extremely low abundance of PLA2 (1.23%) but a high abundance of CTL (51.47%), followed by SVMP (22.06%) and SVSP (10.90%). Apparent interspecific variations in lethality and enzymatic activities were also explored in habu snake venoms, but no variations in myotoxicity were found. Except for SVSP, the resemblance of the relatives within Protobothrops in other venom traits was estimated to deviate from Brownian motion evolution based on phylogenetic signals. A comparative analysis further validated that the degree of covariation between phylogeny and venom variation is evolutionarily labile and varies among clades of closely related snakes. Our findings indicate a high level of interspecific variation in the venom proteomes of habu snakes, both in the presence or absence and the relative abundance of venom protein families, and that these venoms might have evolved under a combination of adaptive and neutral mechanisms.
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Trimeresurus , Animais , Filogenia , Trimeresurus/metabolismo , Serpentes/metabolismo , Venenos de Serpentes , Fosfolipases A2/análise , Proteoma/metabolismoRESUMO
Microplastic (MP) pollution has become a global concern in terms of its environmental abundance and potential detrimental effects. Fibrous microplastics (FMPs) released from synthetic textiles are believed to contribute significantly to environmental MP pollution. This review provides an overview of current knowledge relating to the environmental impact of FMPs through a summary and discussion of (1) the concentrations in different environmental compartments including water, soil and air, (2) emission from wastewater treatment plants: via effluent discharges to waters and via sludge to land, (3) environmental transport and fate, and (4) toxicity and associated effects. How the properties of FMPs influence these aspects is discussed and their behaviour is compared to MPs of other shapes. We have summarised the Environmental Concentrations and derived Predicted No-Effect Concentrations for a preliminary risk assessment of FMPs by extrapolating the risk quotient for each respective environmental compartment. The uncertainties surrounding current assessment methods are discussed. In particular we address the need to improve determination of exposure levels and to better characterise the effects of FMPs. We conclude by presenting topics for future studies to address, which will improve our still limited understanding of the interactions between FMPs and the environment.
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Microplásticos , Poluentes Químicos da Água , Monitoramento Ambiental/métodos , Microplásticos/toxicidade , Plásticos/toxicidade , Têxteis , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidadeRESUMO
Litter decomposition is one of the most important ecosystem processes, which plays a critical role in regu-lating nutrient cycling and energy flow in terrestrial ecosystems. The influence of litter inputs on soil microbial community is helpful for understanding the relationship between soil microbial diversity and terrestrial ecosystem function. We conducted a meta-analysis to examine how litter inputs affect soil microbial activity (fungi, bacteria, actinomycetes) and microbial biomass carbon, nitrogen in China. The results showed that compared with non-litter input, soil microbial biomass carbon and nitrogen were significantly increased by 3.9% and 4.4% respectively after litter inputs. Soil fungal PLFA, bacterial PLFA, and total microbial PLFA were increased by 4.0%, 3.1% and 2.4%, respectively. The effects of litter inputs differed significantly with climatic region, annual precipitation, vege-tation type, and soil pH. Under different climate conditions, the responses of soil microbe showed the trend of subtropical monsoon climatic region > temperate monsoon climatic region > temperate continental climatic region, which increased first and then decreased with increasing annual precipitation. Under different vegetation types, the responses of soil microbes showed the trend of broad-leaved forest > grassland ≈ mixed forest > coniferous forest.
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Microbiota , Solo , Solo/química , Microbiologia do Solo , Nitrogênio/química , Carbono , BactériasRESUMO
To better understand the response of largemouth bass (Micropterus salmoides) to Micropterus salmoides rhabdovirus (MSRV) infection, we investigated the intestinal bacterial flora and transcriptome profile of fish at 72 hours post-infection (hpi). Total of 1574 differentially expressed genes (DEGs) were identified in largemouth bass spleen following MSRV infection, including 573 upregulated and 1001 downregulated genes. KEGG and GO enrichment analysis revealed that upregulated genes were enriched in certain antiviral related signaling pathway, including NOD-like receptor (NLR), RIG-I like receptors (RLR) and regulation of the interferon (IFN)-γ-mediated signaling pathway, whereas some immune-related DEGs enriched in focal adhesion (FA) and ECM-receptor interaction(ECM-RI) were downregulated, as well as genes associated with metabolic processes, such as peroxisome proliferator-activated receptors (PPAR), adipocytokine signaling pathway, Glycerolipid and Retinol metabolism. Furthermore, the principal component analysis (PCA) and phylogenetic analysis revealed that MSRV infection significantly affected the microbiota of largemouth bass intestine; the LEfSe analysis showed that relative abundances of Streptococcus were significantly increased, while the content of Akkermansia, Enterococcus and Lactobacillus were remarkably decreased in the fish intestine following MSRV infection. Additionally, a high correlation was determined between the expressions of interferon-related upregulated genes and the relative abundance of Streptococcus by redundancy analysis (RDA). These results collectively illustrated that intestinal microbiota composition might be associated with the immune-related gene expression in largemouth bass in response to MSRV infection.
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Bass , Infecções por Rhabdoviridae , Rhabdoviridae , Animais , Bass/genética , Transcriptoma , RNA Ribossômico 16S , Receptores Ativados por Proliferador de Peroxissomo , Filogenia , Vitamina A , Interferons/genética , Proteínas NLR/genética , Antivirais , Adipocinas/genéticaRESUMO
Vascular endothelial cells and oxidation reduction system play an important role in the pathogenesis of atherosclerosis (AS). If these conditions are disordered, it will inevitably lead to plaque formation and even rupture. Astragaloside IV (AsIV) and salvianolic acid B (Sal B) are the main active ingredients of Astragalus membranaceus and Salvia miltiorrhiza, respectively, and found to ameliorate vascular endothelial dysfunction and protect against oxidative stress in recent studies. However, it is still unknown if the combination of AsIV and Sal B (AsIV + Sal B) can inhibit the development of plaque through amplifying the protective effect of vascular endothelial cells and anti-oxidative stress effect. To clarify the role of AsIV + Sal B in AS, we observed the efficacy of each group (Control, Model, AsIV, Sal B, and AsIV + Sal B) by biomolecular assays, such as observing the pathological morphology of the aorta by oil red O staining, evaluating the level of oxidative stress and endothelial cells in the serum by the Elisa test, and analyzing the changes of all small molecule metabolites in liver tissue by UPLC-QTOF-MS. Results showed that AsIV, Sal B and AsIV + Sal B decreased the deposition of lipid in the arterial wall, so as to exert the effect of anti-oxidant stress and vascular endothelial protection, where the inhibitory effect of AsIV + Sal B was the most obvious. Metabonomics analysis showed that Sal B regulated the metabolic pathways of arginine and proline. AsIV regulated glycerol metabolism and saturated fatty acid biosynthesis metabolism. AsIV + Sal B is mainly related to the regulation of the citrate cycle (TCA cycle), alanine, aspartic acid, and glutamate metabolism, cysteine, and methionine metabolism. Succinic acid and methionine are synergistic metabolites that exert an enhancing effect when AsIV and Sal B were used in combination. In conclusion, we demonstrated that AsIV acompanied with Sal B can be successfully used for anti-oxidative stress and vascular endothelial protection of AS, and succinic acid and methionine are the synergistic metabolites.
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Aterosclerose , Saponinas , Triterpenos , Antioxidantes , Benzofuranos , Células Endoteliais , Humanos , Metionina , Ácido SuccínicoRESUMO
PURPOSE: To compare the survival outcomes between hepatic resection and transarterial lipiodol chemoembolization (TACE) used as the initial treatment in patients with large (≥5 cm), multiple, and resectable hepatocellular carcinomas. MATERIALS AND METHODS: This study had local ethical committee approval; all patients gave written informed consent. Between January 2004 and December 2006, 168 consecutive patients were prospectively studied. As an initial treatment, 85 patients underwent hepatic resection and 83 underwent TACE. Of the 29 of 83 patients in whom there was a good response to TACE, 13 underwent subsequent hepatic resection. The remaining 16 patients, who refused hepatic resection, underwent TACE and local ablation. Repeated TACE was performed in patients with stable disease or progressive disease after initial TACE. The differences in survival between groups and subgroups were calculated with the Kaplan-Meier method. Univariate and multivariate analyses were performed to clarify the prognostic factors for survival. RESULTS: The 1-, 3-, and 5-year overall survival rates for the initial hepatic resection group and the initial TACE group were 70.6%, 35.3%, 23.9% and 67.2%, 26.0%, 18.9%, respectively (P = .26). Complication rates were significantly higher in the initial hepatic resection group than in the initial TACE group (P < .01). The 1-, 3-, and 5-year overall survival rates in patients who underwent initial TACE and subsequent hepatic resection were 92.3%, 67.3%, and 50.5%, respectively, which were significantly higher than rates in patients treated with initial hepatic resection (P = .04) but were not significantly higher than in patients who responded well to TACE but refused hepatic resection (P = .07). Tumor size was the independent risk factor for survival. CONCLUSION: TACE might be a better initial treatment in patients with large, multiple, and resectable hepatocellular carcinomas; hepatic resection should be recommended to patients who respond well to TACE.
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Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica/estatística & dados numéricos , Óleo Etiodado/administração & dosagem , Hepatectomia/estatística & dados numéricos , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/terapia , Carcinoma Hepatocelular/diagnóstico , China/epidemiologia , Feminino , Hemostáticos/administração & dosagem , Humanos , Injeções Intra-Arteriais , Neoplasias Hepáticas/diagnóstico , Masculino , Pessoa de Meia-Idade , Prevalência , Prognóstico , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Análise de Sobrevida , Taxa de Sobrevida , Resultado do TratamentoRESUMO
BACKGROUND: To retrospectively evaluate the effectiveness and safety of radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC) with a multi-pin bipolar system. METHODS: Between August 2005 and December 2006, 18 patients with 30 HCCs (3.40 ± 1.24 cm, range 1.30-6.0 cm; median number of treated lesions is two per patient, range, 1-3) underwent percutaneous RFA with a multi-pin bipolar system under ultrasound guidance. The primary end-point were treatment efficacy, major and minor complications, and the secondary end-point were overall survival and tumor-free survival. RESULTS: Complete ablation with conformed shape to the index tumor was achieved in 16 of 18 patients, and 28 of the 30 tumors were completely ablated. On follow-up, local and distant intrahepatic tumor progression rates were 12.5% (2 of 16 patients) and 62.5% (10 of 16 patients). There was no patient who developed extrahepatic metastasis. There were no major complications. The 1-, 2-year overall survival rates for all patients were 83.3%, 55.6%, respectively, and the corresponding tumor-free survivals were 50.0%, 22.2%, respectively. CONCLUSION: RFA with a multi-pin bipolar system was effective and safe for HCC. A large ablation volume could be achieved which conformed to the shape of the index tumor.
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Carcinoma Hepatocelular/cirurgia , Ablação por Cateter/instrumentação , Neoplasias Hepáticas/cirurgia , Adulto , Idoso , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/mortalidade , Ablação por Cateter/métodos , Eletrodos , Feminino , Seguimentos , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Análise de Sobrevida , Resultado do Tratamento , Ultrassonografia de IntervençãoRESUMO
BACKGROUND/AIMS: A high prevalence of serum IL-6 has been associated with the pathogenesis of hepatocellular carcinoma (HCC) in both animals and humans. However, it is not clear how the levels of serum IL-6 influence the prognosis of HCC patients. This study was carried out in order to attempt to answer this question. METHODOLOGY: A total of 156 adults were selected and categorized into four groups: healthy subjects (n=18), those with tumor recurrence (n=26), those initially diagnosed with HCC (n=32), and those with HCC (n=80) who received curative resection between 2002 and 2004 with five years of follow-up. Serum IL-6 levels were determined in all subjects by the same ELISA method. RESULTS: IL-6 was found in high levels in the serum of patients initially diagnosed with HCC (8.47±5.92, p<0.0001) and in patients with HCC and tumor recurrence (12±31.90, p=0.001) compared with healthy subjects (0.89±1.51). This includes all patients who received therapy between 2007 and 2008. The levels of serum IL-6 were positively correlated with tumor size (p=0.002) in the HCC patients who received curative resection between 2002 and 2004 with five years of follow-up. CONCLUSIONS: High levels of serum IL-6 correlated positively with tumor size and with poor prognosis in HCC patients.
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Carcinoma Hepatocelular/sangue , Interleucina-6/sangue , Neoplasias Hepáticas/sangue , Adolescente , Adulto , Idoso , Biomarcadores Tumorais/sangue , Carcinoma Hepatocelular/cirurgia , Distribuição de Qui-Quadrado , Ensaio de Imunoadsorção Enzimática , Feminino , Seguimentos , Humanos , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Período Perioperatório , Prognóstico , Modelos de Riscos ProporcionaisRESUMO
The nature of the synergistic effect in bimetallic catalysts remains a challenging issue, due to the difficulty in understanding the adjacent interaction between dual metals at the atomic level. Herein, a CuFe-N/C catalyst featuring diatomic metal-nitrogen sites was prepared through a sequential ion exchange strategy and applied for NO selective catalytic reduction by CO (CO-SCR). The bimetallic CuFe-N/C catalyst exhibits high N2 selectivity with a NO conversion efficiency of nearly 100% over a wide temperature range from 225 to 400 °C, significantly higher than that of its single-component counterparts. The synergistic effect of bimetallic Cu-Fe sites is well revealed using the combined in situ FTIR technique and DFT calculations. Bifunctional Cu-Fe sites are demonstrated not only to provide two different preferential adsorption centers for the CO molecule and ONNO intermediate but also to achieve a complete electron cycle for efficient interfacial electron transfer upon ONNO uptake. The unique electron transfer mechanism stemmed from 4s-3d-type electron coupling, and different 3d shell fillings of Cu (3d10) and Fe (3d6) atoms are presented. These fundamental insights pave the way for the understanding of N-coordinated bimetallic site synergy and rational design of highly active atomic-scale metal catalysts for SCR applications.
RESUMO
Visible-light-driven photocatalytic Cr(VI) reduction is a promising pathway to moderate environmental pollution, in which the development of photocatalysts is pivotal. Herein, three hourglass-type phosphomolybdate-based hybrids with the formula of: (H2 bpe)3 [Zn(H2 PO4 )][Zn(bpe)(H2 O)2 ]H{Zn[P4 Mo6 O31 H6 ]2 } â 6H2 O (1) Na6 [H2 bz]2 [ZnNa4 (H2 O)5 ]{Zn [P4 Mo6 O31 H3 ]2 } â 2H2 O (2) and (H2 mbpy) {[Zn(mbpy)(H2 O)]2 [Zn(H2 O)]2 }{Zn[P4 Mo6 O31 H6 ]2 } â 10H2 O (3) (bpe=trans-1,2-bi(4-pyridyl)-ethylene; bz=4,4'-diaminobiphenyl; mbpy=4,4'-dimethyl-2,2'bipyridine) were synthesized under the guidance of the functional organic moiety modification strategy. Structural analysis showed that hybrids 1-3 have similar 2D layer-like spatial arrangements constructed by {Zn[P4 Mo6 ]2 } clusters and organic components with different conjugated degree. With excellent redox properties and wide visible-light absorption capacities, hybrids 1-3 display favourable photocatalytic activity for Cr(VI) reduction with 79%, 70% and 64% reduction rates, which are superior to that of only inorganic {Zn[P4 Mo6 ]2 } itself (21%). The investigation of organic components on photocatalytic performance of hybrids 1-3 suggested that the organic counter cations (bpe, bz and mbpy) can effectively affect the visible-light absorption, as well as the recombination of photogenerated carriers stemmed from {Zn[P4 Mo6 ]2 } clusters, further promoting their photocatalytic performances towards Cr(VI) reduction. This work provides an experimental basis for the design of functionalized photocatalysts via the modification of organic species.
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AIMS: This study aimed to investigate whether human umbilical cord mesenchymal stem cells (UC-MSCs) can prevent articular cartilage degradation and explore the underlying mechanisms in a rat osteoarthritis (OA) model induced by monosodium iodoacetate (MIA). METHODS: Human UC-MSCs were characterized by their phenotype and multilineage differentiation potential. Two weeks after MIA induction in rats, human UC-MSCs were intra-articularly injected once a week for three weeks. The therapeutic effect of human UC-MSCs was evaluated by haematoxylin and eosin, toluidine blue, Safranin-O/Fast green staining, and Mankin scores. Markers of joint cartilage injury and pro- and anti-inflammatory markers were detected by immunohistochemistry. RESULTS: Histopathological analysis showed that intra-articular injection of human UC-MSCs significantly inhibited the progression of OA, as demonstrated by reduced cartilage degradation, increased Safranin-O staining, and lower Mankin scores. Immunohistochemistry showed that human UC-MSC treatment down-regulated the expression of matrix metalloproteinase-13 (MMP13) and a disintegrin and metalloproteinase with thrombospondin motifs 5 (ADAMTS-5), and enhanced the expression of type II collagen and ki67 in the articular cartilage. Furthermore, human UC-MSCs significantly decreased the expression of interleukin (IL)-1ß and tumour necrosis factor-α (TNF-α), while increasing TNF-α-induced protein 6 and IL-1 receptor antagonist. CONCLUSION: Our results demonstrated that human UC-MSCs ameliorate MIA-induced OA by preventing cartilage degradation, restoring the proliferation of chondrocytes, and inhibiting the inflammatory response, which implies that human UC-MSCs may be a promising strategy for the treatment of OA. Cite this article: Bone Joint Res 2021;10(3):226-236.