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1.
J Magn Reson Imaging ; 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38263789

RESUMEN

BACKGROUND: Insular low-grade gliomas (LGGs) are surgically challenging due to their proximity to critical structures like the corticospinal tract (CST). PURPOSE: This study aims to determine if preoperative CST shape metrics correlate with postoperative motor complications in insular LGG patients. STUDY TYPE: Retrospective. POPULATION: 42 patients (mean age 40.26 ± 10.21 years, 25 male) with insular LGGs. FIELD STRENGTH/SEQUENCE: Imaging was performed using 3.0 Tesla MRI, incorporating T1-weighted magnetization-prepared rapid gradient-echo, T2-weighted space dark-fluid with spin echo (SE), and diffusional kurtosis imaging (DKI) with gradient echo sequences, all integrated with echo planar imaging. ASSESSMENT: Shape metrics of the CST, including span, irregularity, radius, and irregularity of end regions (RER and IER, respectively), were compared between the affected and healthy hemispheres. Total end region radius (TRER) was determined as the sum of RER 1 and RER 2. The relationships between shape metrics and postoperative short-term (4 weeks) and long-term (>8 weeks) motor disturbances assessing by British Medical Research Council grading system, was analyzed using multivariable regression models. STATISTICAL TESTING: Paired t-tests compared CST metrics between hemispheres. Logistic regression identified associations between these metrics and motor disturbances. The models were developed using all available data and there was no independent validation dataset. Significance was set at P < 0.05. RESULTS: Short-term motor disturbance risk was significantly related to TRER (OR = 199.57). Long-term risk significantly correlated with IER 1 (OR = 59.84), confirmed as a significant marker with an AUC of 0.78. Furthermore, the CST on the affected side significantly had the greater irregularity, larger TRER and RER 1, and smaller span compared to the healthy side. DATA CONCLUSION: Preoperative evaluation of TRER and IER 1 metrics in the CST may serve as a tool for assessing the risk of postoperative motor complications in insular LGG patients. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 2.

2.
J Neurooncol ; 166(1): 155-165, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38150062

RESUMEN

OBJECTIVES: This study aims to explore the relationship between the methylation levels of the O-6-methylguanine-DNA methyltransferase (MGMT) promoter and the structural connectivity in insular gliomas across hemispheres. METHODS: We analyzed 32 left and 29 right insular glioma cases and 50 healthy controls, using differential tractography, correlational tractography, and graph theoretical analysis to investigate the correlation between structural connectivity and the methylation level. RESULTS: The differential tractography results revealed that in left insular glioma, the volume of affected inferior fronto-occipital fasciculus (IFOF, p = 0.019) significantly correlated with methylation levels. Correlational tractography results showed that the quantitative anisotropy (QA) value of peritumoral fiber tracts also exhibited a significant correlation with methylation levels (FDR < 0.05). On the other hand, in right insular glioma, anterior internal part of the reticular tract, IFOF, and thalamic radiation showed a significant correlation with methylation levels but at a different correlation direction from the left side (FDR < 0.05). The graph theoretical analysis showed that in the left insular gliomas, only the radius of graph was significantly lower in methylated MGMT group than unmethylated group (p = 0.047). No significant correlations between global properties and methylation levels were observed in insular gliomas on both sides. CONCLUSION: Our findings highlight a significant, hemisphere-specific correlation between MGMT promoter methylation and structural connectivity in insular gliomas. This study provides new insights into the genetic influence on glioma pathology, which could inform targeted therapeutic strategies.


Asunto(s)
Neoplasias Encefálicas , Glioma , Humanos , Metilación de ADN , Glioma/diagnóstico por imagen , Glioma/genética , Glioma/tratamiento farmacológico , Enzimas Reparadoras del ADN/genética , O(6)-Metilguanina-ADN Metiltransferasa/genética , Metilasas de Modificación del ADN/genética , Regiones Promotoras Genéticas , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Proteínas Supresoras de Tumor/genética
3.
Ecotoxicol Environ Saf ; 269: 115788, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38056118

RESUMEN

The contamination of arable land with heavy metals, such as Cd, is a serious concern worldwide. Intercropping with Cd accumulators can be used for efficient safe crop production and phytoremediation of Cd-contaminated soil. However, the effect of intercropping on Cd uptake by main crops and accumulators varies among plant combinations. Rhizosphere interaction may mediate Cd uptake by intercropped plants, but the mechanism is unclear. Thus, in the present study, we aimed to examine the effect of rhizosphere interaction on Cd uptake by intercropping rice (Oryza sativa L.) with mugwort (Artemisia argyi Levl. et Vant.) in Cd-contaminated paddy soil. We grew O. sativa and A. argyi in pots designed to allow different levels of interaction: complete root interaction (no barrier), partial root interaction (nylon mesh barrier), and no root interaction (plastic film barrier). Our results indicated that both complete and partial root interaction increased the shoot and root mass of A. argyi, but did not decrease the shoot, root, and grain mass of O. sativa. Interspecific root interaction significantly increased the Cd content in the shoots, roots, and grains of O. sativa and the shoots of A. argyi. Increased content of total organic acids in the rhizosphere, which increased the content of available Cd, was a possible mechanism of increased Cd uptake in both plants under interspecific root interaction. Our findings demonstrate that an intercropping system can extract more Cd from contaminated soil than a monocropping system of either A. argyi or O. sativa. However, the intercropping system did not facilitate safe crop production because it substantially increased grain Cd content in O. sativa.


Asunto(s)
Oryza , Contaminantes del Suelo , Cadmio/análisis , Suelo , Raíces de Plantas/química , Grano Comestible/química , Biodegradación Ambiental , Contaminantes del Suelo/análisis
4.
Zhongguo Zhong Yao Za Zhi ; 49(7): 1818-1825, 2024 Apr.
Artículo en Zh | MEDLINE | ID: mdl-38812194

RESUMEN

A label-free fluorescence method based on malachite green/aptamer was developed for the detection of ochratoxin A(OTA) in traditional Chinese medicines. Malachite green itself exhibits weak fluorescence. Upon interaction with the aptamer specific to OTA, the G-quadruplex structure of the aptamer provides a protective microenvironment for malachite green, which significantly enhances its fluorescence signal. After OTA is added, preferential binding occurs between the aptamer and OTA, and malachite green will be released from the aptamer, which weakens the fluorescence signal. According to this principle, this paper established a fluorescence method with the aptamer of OTA as the recognition element and malachite green as the fluorescent probe for the detection of OTA in traditional Chinese medicines. The key experimental factors such as the concentrations of metal ions, aptamer, and malachite green were optimized to improve the performance of the method. OTA was detected under the optimal experimental conditions, and the results showed that with the increase in OTA concentration, the fluorescence signal gradually weakened. Within the range of 20-1 000 nmol·L~(-1), the OTA concentration was linearly correlated with the fluorescence signal ratio ΔF/F(ΔF=F_0-F, where F_0 is the fluorescence signal of aptamer/malachite green, and F is the fluorescence signal of OTA/aptamer/malachite green), with R~2 of 0.995. The limit of detection of the established method was 7.1 nmol·L~(-1). Furthermore, three substances structurally similar to OTA and two mycotoxins that may coexist with OTA were selected for experiments, which aimed to examine the cross-reactivity and specificity of the established method. The cross-reactivity experiments demonstrated that the interferers did not significantly affect the fluorescence signal of the detection system. The specificity experiments revealed that when mycotoxins were mixed with OTA, the fluorescence signal generated by the mixture closely resembled that of OTA itself. The results indicated that even in the presence of interferents, the established method remained unaffected and demonstrated excellent specificity. Additionally, this method exhibited remarkable reproducibility and stability. In the case of simple centrifugation and dilution of traditional Chinese medicine samples(Puerariae Lobatae Radix, Sophorae Flavescentis Radix, and Periplocae Cortex), the OTA detection method was applicable, with recovery rates ranging from 91.5% to 121.3%. Notably, this approach does not need complex pretreatment of traditional Chinese medicines while offering simple operation, low detection costs, and short detection time. Furthermore, by incorporating aptamers into the quality evaluation of traditional Chinese medicines, this method expands the application scope of aptamers.


Asunto(s)
Aptámeros de Nucleótidos , Medicamentos Herbarios Chinos , Ocratoxinas , Colorantes de Rosanilina , Colorantes de Rosanilina/química , Colorantes de Rosanilina/análisis , Ocratoxinas/análisis , Ocratoxinas/química , Aptámeros de Nucleótidos/química , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/análisis , Espectrometría de Fluorescencia/métodos , Contaminación de Medicamentos/prevención & control , Fluorescencia , Medicina Tradicional China
5.
J Transl Med ; 21(1): 390, 2023 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-37328854

RESUMEN

BACKGROUND: Tumor cells with the capability of radiation resistance can escape the fate of cell death after radiotherapy, serving as the main cause of treatment failure. Repopulation of tumors after radiotherapy is dominated by this group of residual cells, which greatly reduce the sensitivity of recurrent tumors to the therapy, resulting in poor clinical outcomes. Therefore, revealing the mechanism of radiation resistant cells participating in tumor repopulation is of vital importance for cancer patients to obtain a better prognosis. METHODS: Co-expressed genes were searched by using genetic data of radiation resistant cells (from GEO database) and TCGA colorectal cancer. Univariate and multivariate Cox regression analysis were performed to define the most significant co-expressed genes for establishing prognostic indicator. Logistic analysis, WGCNA analysis, and other types of tumors were included to verify the predictive ability of the indicator. RT-qPCR was carried out to test expression level of key genes in colorectal cancer cell lines. Colongenic assay was utilized to test the radio-sensitivity and repopulation ability of key gene knockdown cells. RESULTS: Prognostic indicator based on TCGA colorectal cancer patients containing four key radiation resistance genes (LGR5, KCNN4, TNS4, CENPH) was established. The indicator was shown to be significantly correlated with the prognosis of colorectal cancer patients undergoing radiotherapy, and also had an acceptable predictive effect in the other five types of cancer. RT-qPCR showed that expression level of key genes was basically consistent with the radiation resistance level of colorectal cancer cells. The clonogenic ability of all key gene knockdown cells decreased after radiation treatment compared with the control groups. CONCLUSIONS: Our data suggest that LGR5, KCNN4, TNS4 and CENPH are correlated with radiation sensitivity of colorectal cancer cells, and the indicator composed by them can reflect the prognosis of colorectal cancer patients undergoing radiation therapy. Our data provide an evidence of radiation resistant tumor cells involved in tumor repopulation, and give patients undergoing radiotherapy an approving prognostic indicator with regard to tumor progression.


Asunto(s)
Neoplasias Colorrectales , Tolerancia a Radiación , Humanos , Pronóstico , Tolerancia a Radiación/genética , Línea Celular Tumoral , Muerte Celular , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/radioterapia , Neoplasias Colorrectales/metabolismo
6.
Virus Genes ; 59(6): 868-873, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37698740

RESUMEN

Clanis bilineata Walker, soybean hawkmoth, belongs to the subfamily Ambulicinae (Sphingidae, Lepidoptera) and is an edible insect that usually grows on soybean leaves. In this study, we isolated a new cypovirus from naturally diseased Clanis bilineata larvae (named CbCPV), scanned its structure, sequenced its genome, and studied its phylogenetic relationship to other cypoviruses. Microscopy showed that CbCPV polyhedral occlusion bodies were about 1.878 µm on average and contained many virions in the ultrathin sections. The complete genome sequence of CbCPV is 22,812 bp comprising 10 segmented double-stranded RNAs. Apart from segment 1 containing one open reading frame (ORF) and one sub-ORF, the other nine segments all contain one open reading frame and encoded one putative protein. The non-coding regions contained conserved sequences at 5' termini (AGUCAAA) and 3' termini (AGC), except segment 4 containing a different 5' termini (AUGUUUA). The whole sequence of the polyhedrin gene in CbCPV contained 892 nucleotides, encoding a protein of 246 amino acids. Based on amino acid sequences of polyhedrin or RNA dependent RNA polymerase (RdRp), the phylogenetic analysis indicated that CbCPV was closely related to DnCPV-23. The putative function of all segments differed from each other, but the most closely related species of segments were DnCPV-23 with 98.2-99.8% nucleotide identity. Overall, the evidence of morphology, protein analysis and nucleic acids (genomic pattern) showed that CbCPV is a new isolate in the cypovirus-23 type and can be termed Clanis bilineata cypovirus type 23 (CbCPV-23).


Asunto(s)
Mariposas Nocturnas , Reoviridae , Animales , Reoviridae/genética , Filogenia , Genoma Viral/genética , Proteínas Virales/genética , Genómica , ARN Viral/genética
7.
Thorax ; 77(6): 621-624, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-34996851

RESUMEN

Chronic refractory cough (CRC) is characterised by cough hypersensitivity. Interferon-γ (IFN-γ) has been reported to induce calcium influx, action potentials of vagal neurons in vitro and cough response in guinea pigs. While the effect of IFN-γ in CRC patients remains unknown. Here, via flow-cytometry and inhalation cough challenge, we found CRC patients had significantly increased levels of sputum IFN-γ+CD4+ T cells, IFN-γ+CD8+ T cells as well as supernatant of IFN-γ. The average number of coughs in CRC patients increased as the concentration of inhaled IFN-γ went up in IFN-γ cough challenge. Two or more coughs and five or more coughs elicited by inhaled IFN-γ in CRC patients occurred in 7 of 10 and 2 of 10, respectively. Preinhaled IFN-γ (100 µg/mL) increased the capsaicin cough sensitivity in CRC patients but not healthy volunteers. Targeting IFN-γ may be a potential effective anti-tussive strategy in CRC patients.


Asunto(s)
Tos , Interferón gamma , Linfocitos T CD8-positivos , Capsaicina/farmacología , Enfermedad Crónica , Humanos
8.
Opt Lett ; 47(11): 2907-2910, 2022 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-35648961

RESUMEN

We demonstrate a monolithic frequency-modulated continuous-wave (FMCW) lidar chip with an integrated transceiver array based on lens-assisted beam steering (LABS) technology. It enables beam emitting, steering, receiving, and coherent detecting on a single chip with simultaneous distance and velocity detection. An integrated transceiver is designed with a composite structure of a Bragg grating in the middle and a U-shaped photodetector (PD) surrounding it. For a proof-of-concept demonstration, a chip with 2 × 2 switchable transceiver array is fabricated. A monolithic coherent LABS lidar system with a scanning angle of 2.86° and a scanning speed of 5.3 µs is implemented for 5 m ranging and 0.45 m/s velocity detection.

9.
FASEB J ; 35(5): e21428, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33774861

RESUMEN

This study was conducted to investigate whether a transient receptor potential ankyrin 1 (TRPA1) antagonist (HC-030031) can reduce airway inflammation and hyperresponsiveness in a murine allergic rhinitis (AR) model. BALB/c mice were sensitized and challenged by ovalbumin (OVA) to induce AR. HC-030031 or vehicle was administrated to mice via intraperitoneal injection prior to OVA challenges. Nose-scratching events, histopathologic alterations of the airways, and bronchial hyperresponsiveness (BHR) were assessed. Differential cells and proinflammatory cytokines in the nasal lavage (NAL) and bronchoalveolar lavage (BAL) fluid were measured. Expressions of TRPA1 in nasal mucosa were examined by immunohistochemistry. TRPA1-expressing vagal neurons were labeled by immunofluorescent staining. HC-030031-treated AR mice had markedly reduced type-2 inflammation in nasal mucosa and ameliorated-nose-scratching events than AR mice received vehicle. HC-030031 treatment also dramatically reduced leucocyte numbers and IL-8 level in the BAL fluid, inhibited lower airway remodeling and fibrosis, and nearly abolished BHR. HC-0300031 treatment significantly inhibited the upregulated number of TRPA1 expressing nasal epithelial cells and TRPA1 expressing sensory neurons, leading to downregulation of SP in both upper and lower airways. Targeting TRPA1 may represent a promising strategy for treating AR and AR-related asthma.


Asunto(s)
Asma/prevención & control , Hiperreactividad Bronquial/prevención & control , Modelos Animales de Enfermedad , Inflamación/prevención & control , Rinitis Alérgica/complicaciones , Canal Catiónico TRPA1/antagonistas & inhibidores , Remodelación de las Vías Aéreas (Respiratorias) , Animales , Asma/etiología , Asma/patología , Hiperreactividad Bronquial/etiología , Hiperreactividad Bronquial/patología , Femenino , Inflamación/etiología , Inflamación/patología , Ratones , Ratones Endogámicos BALB C
10.
Anim Biotechnol ; 33(6): 1205-1216, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34010090

RESUMEN

Genetic analysis of porcine growth and fatness traits is beneficial to the swine industry and provides a reference to understand human obesity. Here, we obtained 29 growth and fatness traits for 473 individuals from a White Duroc × Erhualian F3 intercross population. Basic statistical analyses showed that: (1) Positive correlations between different-stage body weights were detected, the shorter the time interval the stronger the correlation. (2) Strong correlations existed in the paired fatness traits. (3) With the growth of age, the correlation between fatness and body weight was increasing. All pigs were genotyped by Illumina 50 K SNP chips and their whole-genome genotypes were imputed referred to 109 re-sequencing data. We performed common and imputation-based GWASs for these traits. Two genome-wide significant loci on swine chromosome (SSC) 4 and 7 were repeatedly detected. The strongest association (P = 3.24 × 10-19) was detected at 31.96 Mb on SSC7 for leaf fat weight. On this locus, seven major haplotypes were identified, of which two were novel and had an increasing-fatness effect. In the imputation-based GWAS, three new loci were identified. Our findings provide further insights into and enhance our understanding of genetic mechanism of porcine growth and fat deposition.


Asunto(s)
Estudio de Asociación del Genoma Completo , Obesidad , Sitios de Carácter Cuantitativo , Animales , Humanos , Genotipo , Haplotipos/genética , Fenotipo , Sitios de Carácter Cuantitativo/genética , Porcinos/genética , Obesidad/genética
11.
Zhongguo Zhong Yao Za Zhi ; 47(1): 203-223, 2022 Jan.
Artículo en Zh | MEDLINE | ID: mdl-35178927

RESUMEN

This study aims to explore the molecular mechanism of Ganoderma against gastric cancer based on network pharmacology, molecular docking, and cell experiment. The active components and targets of Ganoderma were retrieved from Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform(TCMSP), and gastric cancer-related targets from GeneCards and Online Mendelian Inheritance in Man(OMIM). The protein-protein interaction(PPI) network of the common targets was constructed with STRING, followed by Gene Ontology(GO) term enrichment and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway enrichment analysis of the common genes based on Bioconductor and R language. The medicinal-disease-component-target network and medicinal-disease-component-target-pathway network were established by Cytoscape. Molecular docking was performed between ß-sitosterol(the key component in Ganoderma) and the top 15 targets in the PPI network. Cell experiment was performed to verify the findings. A total of 14 active components and 28 targets of Ganoderma were retrieved, and the medicinal and the disease shared 25 targets, including caspase-3(CASP3), caspase-8(CASP8), caspase-9(CASP9), and B-cell lymphoma-2(BCL2). The common targets involved 72 signaling pathways and apoptosis and p53 signaling pathway may play a crucial role in the effect of Ganoderma against gastric cancer. ß-sitosterol had strong binding activity to the top 15 targets in the PPI network. The in vitro cell experiment demonstrated that ß-sitosterol inhibited gastric cancer AGS cell proliferation by inducing cell apoptosis and cell cycle arrest in the S phase, which might be related to the regulation of the p53 pathway. This study shows the multi-component, multi-target, and multi-pathway characteristics of Ganoderma against gastric cancer, which lays a scientific basis for further research on the molecular mechanism.


Asunto(s)
Ganoderma , Medicina Tradicional China , Neoplasias Gástricas , Humanos , Simulación del Acoplamiento Molecular , Farmacología en Red , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/genética
12.
FASEB J ; 34(6): 7970-7988, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32293074

RESUMEN

Cancer-associated fibroblasts (CAFs) are an important component of the tumor microenvironment and contribute to tumor cell proliferation and metastasis. Microfibrillar-associated protein 5 (MFAP5), a component of elastic microfibers and an oncogenic protein in several types of tumors, is secreted by CAFs. However, the role of MFAP5 in the bladder cancer remains unclear. Here, we report that MFAP5 is upregulated in bladder cancer and is associated with poor patient survival. Downregulation of MFAP5 in CAFs led to an impairment in proliferation and invasion of bladder cancer cells. Luciferase reporter assays and electrophoretic mobility shift assays (EMSA) showed QKI directly downregulates MFAP5 in CAFs. In addition, CAFs-derived MFAP5 led to an activation of the NOTCH2/HEY1 signaling pathway through direct interaction with the NOTCH2 receptor, thereby stimulating the N2ICD release. RNA-sequencing revealed that MFAP5-mediated PI3K-AKT signaling activated the DLL4/NOTCH2 pathway axis in bladder cancer. Moreover, downregulation of NOTCH2 by short hairpin RNA or the inactivating anti-body NRR2Mab was able to reverse the adverse effects of MFAP5 stimulation in vitro and in vivo. Together, these results demonstrate CAFs-derived MFAP5 promotes the bladder cancer proliferation and metastasis and provides new insight for targeting CAFs as novel diagnostic and therapeutic strategy.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Fibroblastos Asociados al Cáncer/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteínas Contráctiles/metabolismo , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Receptor Notch2/metabolismo , Transducción de Señal/fisiología , Neoplasias de la Vejiga Urinaria/metabolismo , Animales , Línea Celular Tumoral , Movimiento Celular/fisiología , Proliferación Celular/fisiología , Progresión de la Enfermedad , Regulación hacia Abajo/fisiología , Regulación Neoplásica de la Expresión Génica/fisiología , Humanos , Masculino , Ratones , Ratones Desnudos , Fosfatidilinositol 3-Quinasas/metabolismo , Microambiente Tumoral/fisiología , Regulación hacia Arriba/fisiología
13.
Inorg Chem ; 60(2): 1241-1247, 2021 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-33373217

RESUMEN

Double perovskite oxides with d8-d3 electronic configurations are expected to be ferromagnetic from the Goodenough-Kanamori rules, such as ferromagnetic La2NiMnO6. In search of new ferromagnetic insulators, double perovskite Ba2NiIrO6 was successfully synthesized by high-pressure and high-temperature methods (8 GPa and 1573 K). Ba2NiIrO6 crystallizes in a cubic double perovskite structure (space group: Fm3̅m), with an ordered arrangement of NiO6 and IrO6 octahedra. X-ray absorption near-edge spectroscopy confirms the nominal Ni(II) and Ir(VI) valence states. Ba2NiIrO6 displays an antiferromagnetic order at 51 K. The positive Weiss temperature, however, indicates that ferromagnetic interactions are dominant. Isothermal magnetization curves at low temperatures support a field-induced spin-flop transition.

14.
Inorg Chem ; 60(7): 4424-4433, 2021 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-33705141

RESUMEN

A polycrystalline sample of Tl2Ir2O7 was synthesized by high-pressure and high-temperature methods. Tl2Ir2O7 crystallizes in the cubic pyrochlore structure with space group Fd3̅m (No. 227). The Ir4+ oxidation state is confirmed by Ir-L3 X-ray absorption near-edge spectroscopy. Combined temperature-dependent magnetic susceptibility, resistivity, specific heat, and DFT+DMFT calculation data show that Tl2Ir2O7 is a Pauli paramagnetic metal, but it is close to a metal-insulator transition. The effective ionic size of Tl3+ is much smaller than that of Pr3+ in metallic Pr2Ir2O7; hence, Tl2Ir2O7 would be expected to be insulating according to the established phase diagram of the pyrochlore iridate compounds, A3+2Ir4+2O7. Our experimental and theoretical studies indicate that Tl2Ir2O7 is uniquely different from the current A3+2Ir4+2O7 phase diagram. This uniqueness is attributed primarily to the electronic configuration difference between Tl3+ and rare-earth ions, which plays a substantial role in determining the Ir-O-Ir bond angle, and the corresponding electrical and magnetic properties.

15.
Small ; 16(34): e2002699, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32700376

RESUMEN

2D materials hold promising potential for novel gas separation. However, a lack of in-plane pores and the randomly stacked interplane channels of these membranes still hinder their separation performance. In this work, ferrocene based-MOFs (Zr-Fc MOF) nanosheets, which contain abundant of in-plane micropores, are synthesized as porous supports to fabricate Zr-Fc MOF supported ionic liquid membrane (Zr-Fc-SILM) for highly efficient CO2 separation. The micropores of Zr-Fc MOF nanosheets not only provide extra paths for CO2 transportation, and thus increase its permeance up to 145.15 GPU, but also endow the Zr-Fc-SILM with high selectivity (216.9) of CO2 /N2 through the nanoconfinement effect, which is almost ten times higher than common porous polymer SILM. Furthermore, based on the photothermal-responsive properties of Zr-Fc MOF, the performance is further enhanced (35%) by light irradiation through a photothermal heating process. This provides a brand new way to design light facilitating gas separation membranes.

16.
Small ; 16(11): e1907016, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32083785

RESUMEN

Type II porous liquids are demonstrated to be promise porous materials. However, the category of porous hosts is very limited. Here, a porous host metal-organic polyhedra (MOP-18) is reported to construct type II porous liquids. MOP-18 is dissolved into 15-crown-5 as an individual cage (5 nm). Both the molecular dynamics simulations and experimental gravimetric CO2 solubility test indicate that the inner cavity of MOP-18 in porous liquids is unoccupied by 15-crown-5 and is accessible to CO2 . Thus, the prepared porous liquids show enhanced gas solubility. Furthermore, the prepared porous liquid is encapsulated into graphene oxide (GO) nanoslits to form a GO-supported porous liquid membrane (GO-SPLM). Owing to the empty cavity of MOP-18 unit cages in porous liquids that reduces the gas diffusion barrier, GO-SPLM significantly enhances the permeability of gas.

17.
Inorg Chem ; 59(6): 3579-3584, 2020 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-32100540

RESUMEN

A new polar and magnetic oxide, LuCrWO6, was synthesized under high pressure (6 GPa) and high temperature (1673 K). LuCrWO6 is isostructural with the previously reported polar YCrWO6 (SG: Pna21, no. 33). The ordering of CrO6 and WO6 octahedra in the edge-shared dimers induce the polar structure. The effective size of rare earth, Ln cation does not seem to affect the symmetry of LnCrWO6. Second harmonic generation measurements of LuCrWO6 confirmed the noncentrosymmetric character and strong piezoelectric domains are observed from piezoresponse force microscopy at room temperature. LuCrWO6 exhibits antiferromagnetic behavior, TN, of ∼18 K with a Weiss temperature of -30.7 K.

18.
Inorg Chem ; 59(19): 14513-14525, 2020 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-32941030

RESUMEN

The application of LuBO3:Ce3+ (LBO:Ce) crystal as an excellent scintillation material has been limited due to its poor phase stability at high temperature or high pressure, so improving the phase stability is essential for promoting its development. Ga stabilized LuBO3:Ce3+ (LGBO:Ce) is synthesized by solid-state reaction at 1200 °C. Powder X-ray diffraction patterns and Raman spectra at ambient pressure show that all the samples are pure calcite phase. In situ high-pressure synchrotron radiation XRD patterns illustrate that calcite phase LGBO:Ce exhibits more excellent phase stability than that of LBO:Ce under high pressure due to the superior compressibility of the [GaO6] octahedral unit. The optical band gap of LGBO decreases from 5.58 to 4.64 eV after introducing 10% Ga, which leads to the decreased nonradiative transition and about double luminescence intensity as expected. More interestingly, the charge transition from O2- to Ce4+ is observed at about 290 nm in the absorption spectra. The X-ray photoelectron spectroscopy spectra indicate the ratio of Ce4+/Ce3+ increases with increasing concentration of Ga3+, which can be attributed to the variation of energy separation between the 4f ground state of Ce3+ and the Fermi energy level position. In contrast to the enhancement of PL intensity, the integrated X-ray excited luminescence intensity decreases after Ga3+ incorporation attributing to the result of both decreased effective atomic number and ionization energy between 5d1 level and conduction band. The thermal luminescence spectra show that after the incorporation of Ga3+ the oxygen vacancy and intrinsic defects in LBO remain unchanged but that the concentration of oxygen vacancy significantly reduces. The mechanism of Ga3+ incorporation on phase stability and luminescence properties of LBO:Ce has been proposed and discussed systematically.

19.
Inorg Chem ; 59(8): 5377-5385, 2020 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-32243145

RESUMEN

The report on the superconductivity of the two-legged spin ladders BaFe2S3 and BaFe2Se3 has established 123-type iron chalcogenides as a novel subgroup in the iron-based superconductor family and has stimulated the continuous exploration of other iron-based materials with new structures and potentially novel properties. In this paper, we report the systematic study of a new quasi-one-dimensional (1D) iron-based compound, Ba9Fe3Te15, including its synthesis and magnetic properties. The high-pressure synthesized Ba9Fe3Te15 crystallized in a hexagonal structure that mainly consisted of face-sharing FeTe6 octahedral chains running along the c axis, with a lattice constant of a = 10.23668 Å; this led to weak interchain coupling and an enhanced one-dimensionality. The systematic static and dynamic magnetic properties were comprehensively studied experimentally. The dc magnetic susceptibility showed typical 1D antiferromagnetic characteristics, with a Tmax at 190 K followed by a spin glass (SG) state with freezing at Tf ≈ 6.0 K, which were also unambiguously proved by ac susceptibility measurements. Additionally, X-ray magnetic circular dichroism (XMCD) experiments revealed an unexpected orbital moment for Fe2+, i.e., 0.84 µB per Fe in Ba9Fe3Te15. The transport property is electrically insulating, with a thermal activation gap of 0.32 eV. These features mark Ba9Fe3Te15 as an alternative type of iron-based compound, providing a diverse candidate for high-pressure studies in order to pursue some emerging physics.

20.
BMC Gastroenterol ; 20(1): 363, 2020 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-33129276

RESUMEN

BACKGROUND: The development of gallbladder disease (GBD) is related to bile acid (BA) metabolism, and the rate of BA circulation increases the risk of biliary cancer. However, it is unclear whether patterns of circulating bile acids (BAs) change in patients with benign GBDs such as gallbladder stones and polyps. Herein, we compared and characterised plasma BA profiles in patients with cholecystolithiasis and non-neoplastic polyps with healthy controls, and explored relationships between plasma BA profiles, demographics, and laboratory test indices. METHODS: A total of 330 subjects (13 healthy controls, 292 cholecystolithiasis and 25 non-neoplastic polyps) were recruited and plasma BA profiles including 14 metabolites from patients with pathologically confirmed cholecystolithiasis and non-neoplastic polyps were compared with controls. BAs were quantitated by liquid chromatography and mass spectrometry, and statistical and regression analyses of demographics and laboratory test indices were performed. RESULTS: Females displayed a higher burden of GBD than males (63.36% cholecystolithiasis, 60% non-neoplastic polyps). Cholecystolithiasis and non-neoplastic polyps were associated with increased plasma total secondary BAs, while levels of primary BAs were lower than in healthy controls. Plasma ursodeoxycholic acid (UDCA), tauroursodeoxycholic acid (TUDCA), glycyurdeoxycholic acid (GUDCA), taurochenodeoxycholic acid (TCDCA) and glycochenodeoxycholic acid (GCDCA) were decreased significantly in GBDs, and ursodeoxycholic acid (UDCA) was negatively correlated with white blood cell count and neutrophil percentage. CONCLUSIONS: Secondary BA levels were higher in patients with cholecystolithiasis and non-neoplastic polyps. White blood cell count and percentage of neutrophil in peripheral blood were negatively correlated with UDCA, indicating an anti-inflammation effect of UDCA.


Asunto(s)
Cálculos Biliares , Pólipos , Ácidos y Sales Biliares , Femenino , Humanos , Masculino
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