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1.
Inorg Chem ; 61(10): 4428-4441, 2022 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-35234043

RESUMO

The syntheses of valence tautomeric compounds with multistep transitions using new redox-active ligands are the long-term goal of the field of bistable materials. The redox-active tetraoxolene ligand, 2,7-di-tert-butylpyrene-4,5,9,10-tetraone (pyreneQ-Q), is now developed to synthesize a pair of dinuclear compounds {[CoL2]2(pyreneSq-Sq)}[Co(CO)4]2·xCH2Cl2·2C6H5CH3 (1, x = 2, L = 1,10-phenanthroline, phen; 2, x = 1.5, L = 2,2'-bipyridine, bpy). Variable-temperature magnetic susceptibilities and single-crystal X-ray diffraction measurements indicate a partial one-step valence tautomeric transition for 1 and a rare two-step valence tautomeric transition for 2, respectively. DFT calculation results are consistent with the experimental data, revealing the correlation between thermodynamic parameters and the one-step/two-step valence tautomeric behaviors.

2.
Inorg Chem ; 57(20): 12509-12520, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30281291

RESUMO

The facile one-step assembly reaction of Na2WO4·2H2O, Sn(CH3)2Cl2, RE(NO3)3·6H2O and K2TeO3 in the presence of dimethylamine hydrochloride as an organic solubilizing agent in acidic aqueous solution resulted in a family of dimethyltin-functionalized rare-earth (RE) incorporated tellurotungstates consisting of {B-α-TeW7O28} and {W5O18} mixed building units [H2N(CH3)2]8Na4H2[RE2(OH)(B-α-TeW7O28)Sn2(CH3)4(W5O18)]2·18H2O [RE = ErIII (1), YbIII (2), HoIII (3), YIII (4)]. The most striking structural characteristic of 1-4 is that they all contain a novel tetrameric S-shaped [RE2(OH)(B-α-TeW7O28)Sn2(CH3)4(W5O18)]214- moiety simultaneously including two pentavacant Keggin [B-α-TeW7O28]12- and two monovacant Lindqvist [W5O18]6- fragments connected by RE and dimethyltin linkers. To the best of our knowledge, such dimethyltin-functionalized RE-containing tellurotungstates have not been reported before. The visible or NIR solid-state emission spectra of 1 and 3 display the characteristic emission bands arising from ErIII and HoIII centers. Moreover, various 1-Er/Yb co-doped samples were prepared by controlling different mass ratio of Er(NO3)3·6H2O/Yb(NO3)·6H2O in the range of 0.96:0.04-0.02:0.98. In the visible region, the emission intensity of the 1-Er0.40/Yb0.60 co-doped sample reaches the maximum at the mass ratio of Er(NO3)3·6H2O/Yb(NO3)·6H2O being 0.40:0.60, and this observation is mainly derived from the fact that the Yb3+ ions can sensitize the Er3+ ions to enhance the emission intensity in the visible region. However, no such phenomenon for the 1-Er/Yb co-doped samples is seen in the NIR region. Besides, the upconversion spectra of the 1-Er/Yb co-doped samples were first observed. In addition, the thermal stabilities of 1-4 were also investigated on the crystalline samples and the thermal decomposition process of 1 has been deeply studied.

3.
Chemistry ; 23(11): 2673-2689, 2017 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-27982476

RESUMO

Three types of serine-decorated rare- earth-containing arsenotungstate [H2 N(CH3 )2 ]6 NaH[RE2 W4 O10 (H2 O)8 (Ser)2 (B-α-AsW9 O33 )2 ]⋅30 H2 O (RE3+ =Eu3+ , Gd3+ , Tb3+ , Dy3+ , Ho3+ , Er3+ , Tm3+ , Yb3+ , and Y3+ ; 1), [H2 N(CH3 )2 ]6 Na6-x REx H4-2 x [RE4 W8 O19 (H2 O)10+y (OH)2 (Ser)2 (B-α-AsW9 O33 )4 ]⋅n H2 O (RE3+ =Tb3+ , x=1, y=2, n=36; RE3+ =Dy3+ , Ho3+ , Er3+ , Yb3+ , Y3+ , x=0, y=0, n=38; RE3+ = Tm3+ , x=1, y=0, n=38; Ser=serine; 2), and [H2 N(CH3 )2 ]6-2 x Na2+3 x REx H10-6 x+y [RE4 W8 O19 (H2 O)8 (OH)2 (Ser)4 (B-α-AsW9 O33 )4 ]⋅Cly ⋅n H2 O (RE3+ =Ce3+ , Pr3+ , x=1, y=0, n=65; RE3+ =Nd3+ , Sm3+ , x=0, y=0, n=65; RE3+ =Eu3+ , Gd3+ , x=1, y=2, n=45; 3) were synthesized with the participation of the organic solubilizers dimethylamine hydrochloride and l-serine and were structurally characterized. The use of different amounts of rare-earth salts results in the structural transformation from dimerization to tetramerization of types 1-3. Type 1 is a dimeric sandwich-type assembly of a dual-Ser-participating [RE2 W4 O10 (H2 O)8 (Ser)2 ]10+ entity sandwiched by two [B-α-AsW9 O33 ]9- moieties, whereas types 2 and 3 have a tetrameric square structure formed by four [B-α-AsW9 O33 ]9- moieties that anchor a dual/tetra- Ser-participating [RE4 W8 O19 (H2 O)10+y (OH)2 (Ser)2 ]20+ or [RE4 W8 O19 (H2 O)8 (OH)2 (Ser)4 ]20+ core. The solid-state luminescence properties and lifetime-decay behaviors of these compounds were investigated. The chromaticity coordinates, dominant wavelengths, color purities, and correlated color temperatures were also calculated.

4.
Cell Metab ; 36(6): 1320-1334.e9, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38838643

RESUMO

Circadian homeostasis in mammals is a key intrinsic mechanism for responding to the external environment. However, the interplay between circadian rhythms and the tumor microenvironment (TME) and its influence on metastasis are still unclear. Here, in patients with colorectal cancer (CRC), disturbances of circadian rhythm and the accumulation of monocytes and granulocytes were closely related to metastasis. Moreover, dysregulation of circadian rhythm promoted lung metastasis of CRC by inducing the accumulation of myeloid-derived suppressor cells (MDSCs) and dysfunctional CD8+ T cells in the lungs of mice. Also, gut microbiota and its derived metabolite taurocholic acid (TCA) contributed to lung metastasis of CRC by triggering the accumulation of MDSCs in mice. Mechanistically, TCA promoted glycolysis of MDSCs epigenetically by enhancing mono-methylation of H3K4 of target genes and inhibited CHIP-mediated ubiquitination of PDL1. Our study links the biological clock with MDSCs in the TME through gut microbiota/metabolites in controlling the metastatic spread of CRC, uncovering a systemic mechanism for cancer metastasis.


Assuntos
Relógios Circadianos , Microbioma Gastrointestinal , Células Supressoras Mieloides , Animais , Camundongos , Células Supressoras Mieloides/metabolismo , Humanos , Metástase Neoplásica , Neoplasias Colorretais/patologia , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/microbiologia , Camundongos Endogâmicos C57BL , Masculino , Microambiente Tumoral , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/secundário , Neoplasias Pulmonares/metabolismo , Feminino , Camundongos Endogâmicos BALB C , Linhagem Celular Tumoral
5.
PLoS One ; 17(6): e0262471, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35657779

RESUMO

Abnormal heart rhythm is a common cardiac dysfunction in obese patients, and its pathogenesis is related to systemic lipid accumulation. The cardiomyocyte-derived apoLpp (homologous gene in Drosophila of the human apolipoprotein B) plays an important role in whole-body lipid metabolism of Drosophila under a high-fat diet (HFD). Knockdown of apoLpp derived from cardiomyocytes can reduce HFD-induced weight gain and abdominal lipid accumulation. In addition, exercise can reduce the total amount of apoLpp in circulation. However, the relationship between regular exercise, cardiomyocyte-derived apoLpp and abnormal heart rhythm is unclear. We found that an HFD increased the level of triglyceride (TG) in the whole-body, lipid accumulation and obesity in Drosophila. Moreover, the expression of apoLpp in the heart increased sharply, the heart rate and arrhythmia index increased and fibrillation occurred. Conversely, regular exercise or cardiomyocyte-derived apoLpp knockdown reduced the TG level in the whole-body of Drosophila. This significantly reduced the arrhythmia induced by obesity, including the reduction of heart rate, arrhythmia index, and fibrillation. Under HFD conditions, flies with apoLpp knockdown in the heart could resist the abnormal cardiac rhythm caused by obesity after receiving regular exercise. HFD-induced obesity and abnormal cardiac rhythm may be related to the acute increase of cardiomyocyte-derived apoLpp. Regular exercise and inhibition of cardiomyocyte-derived apoLpp can reduce the HFD-induced abnormal cardiac rhythm.


Assuntos
Dieta Hiperlipídica , Drosophila melanogaster , Animais , Apolipoproteínas B/metabolismo , Arritmias Cardíacas/complicações , Arritmias Cardíacas/genética , Dieta Hiperlipídica/efeitos adversos , Drosophila/genética , Drosophila melanogaster/genética , Exercício Físico , Humanos , Miócitos Cardíacos/metabolismo , Obesidade/metabolismo
6.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 8): o2184, 2011 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-22091193

RESUMO

In the title mol-ecule, C(4)H(6)N(8)S(2), two tetra-zole rings linked by a disulfide bridge form a dihedral angle of 71.32 (7)° [C-S-S-C torsion angle = -80.51 (10)°]. In the crystal, strong inter-molecular π-π inter-actions between the tetra-zole rings [centroid-centroid distance = 3.285 (3) Å] link pairs of mol-ecules into centrosymmetric dimers. Weak inter-molecular C-H⋯N hydrogen bonds further link these dimers, related by translation in the [100] direction, into columns.

7.
J Hazard Mater ; 402: 123508, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32721641

RESUMO

Plasmonic Au-Ag/TiO2 bimetallic nanocatalyst is regarded as a promising visible-light (VL) photocatalyst due to its wide light absorption and potentially enhanced activity. For its preparation, Au precursors usually contain Cl and co-impregnation/co-deposition suffers from AgCl precipitation, and consequently Au and Ag have to be sequentially supported. However, Au and Ag species of the sequential preparation are individually isolated and difficult to be homogeneously mixed. Here we report an Au-Ag plasmonic nanocatalyst achieved by plasma restructuring and activation from the sequential preparation. The isolated cationic Au and Ag species on the sequentially-prepared Au-Ag/TiO2 sample are restructured to be homogeneously mixed and highly activated by O2 plasma, which can be partially auto-reduced to Au-Ag bimetallic nanoparticles within the induction period of a few minutes in VL photocatalytic oxidation of CO. The Au-Ag plasmonic nanocatalyst exhibits a strongly enhanced activity in the VL photocatalytic reaction. The contribution of O2 plasma treatment and the enhancement mechanism for the Au-Ag plasmonic nanocatalyst are disclosed.

8.
Front Psychiatry ; 12: 624993, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34899404

RESUMO

Purpose: This study explored the association between peripheral blood oxytocin (OT) and social anxiety disorder (SAD) and cue-induced cravings in female heroin addicts. The effect of exercise on alleviation of SAD and OT levels was also explored. Methods: A total of 72 females with heroin dependence were assigned to three groups based on SAD severity. The three groups were Non-SAD control, SAD control, and SAD exercise groups. Subjects in the SAD exercise group underwent aerobic exercise and resistance training for 8 weeks (60 min/day, 5 days/week). Enzyme-linked immunosorbent assay analysis and Liebowitz Social Anxiety Scale (LSAS) scores were used to determine plasma OT concentration and SAD, respectively. Cue-induced craving was assessed using Visual Analog Scale (VAS) and Desires for Drug Questionnaire (DDQ). Mixed-effect analysis of variance and Pearson correlation analysis were used to explore the effect and correlation between different parameters. Results: OT levels in the SAD exercise group were significantly high after exercise (p < 0.01). LSAS, VAS, and DDQ ("Desire and Intention" and "Negative reinforcement") scores in the SAD exercise group were significantly lower after exercise (p < 0.01). Plasma OT level was negatively correlated with LSAS score (r = -0.534, p < 0.001), VAS score (r = -0.609, p < 0.001), "Desire and Intention" score (r = -0.555, p < 0.001), and "Negative reinforcement" score (r = -0.332, p < 0.01) and positively correlated with the "control" score (r = 0.258, p < 0.05). LSAS was positively correlated with VAS score (r = 0.588, p < 0.001) and "Desire and Intention" score (r = 0.282, p < 0.05). Conclusions: The findings of the present study indicate that plasma OT is a potential peripheral biomarker for prediction of the severity of social anxiety in female heroin withdrawal patients. Aerobic exercise combined with resistance training plus incremental load for 8 weeks can increase plasma OT levels and significantly reduce severity of SAD and cue-induced cravings in female heroin addicts.

9.
Signal Transduct Target Ther ; 6(1): 115, 2021 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-33707428

RESUMO

The mechanisms and key factors involved in tumor environments for lung metastasis of CRC are still unclear. Here, using clinical samples from lung metastases of CRC patients, we found that intestinal immune network for IgA production was significantly dysregulated in lung metastases of CRC. Single-cell RNA sequencing discovered a subtype of B cells positive for Erbin, one member of the leucine-rich repeat and PDZ domain (LAP) family, was involved in the lung metastases. Erbin deletion in B cells suppressed lung metastasis of CRC in vivo. And, deletion of Erbin in B cells enhanced the killing effects of CD8+ T cells on tumor cells. Mechanistically, Erbin knockout attenuated TGFß-mediated suppression of migration of CXCR5+ IgA+ cells and STAT6-mediated PD1 expression. Our study uncovered a key role of Erbin in regulating PD1+ IgA+ B cells in lung metastasis of CRC. Targeting Erbin as well as combined use of neutralizing B cells and antibodies neutralizing PD1 suppresses lung metastasis of CRC in mice, suggesting the potential option for treatment of lung metastasis of CRC.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Neoplasias Colorretais/terapia , Neoplasias Pulmonares/terapia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptores CXCR5/genética , Proteínas Adaptadoras de Transdução de Sinal/antagonistas & inibidores , Proteínas Adaptadoras de Transdução de Sinal/imunologia , Idoso , Animais , Anticorpos Neutralizantes/farmacologia , Linfócitos T CD8-Positivos/imunologia , Linhagem Celular Tumoral , Neoplasias Colorretais/genética , Neoplasias Colorretais/imunologia , Feminino , Regulação Neoplásica da Expressão Gênica/imunologia , Xenoenxertos , Humanos , Imunoglobulina A/biossíntese , Imunoglobulina A/imunologia , Intestinos/imunologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/secundário , Masculino , Camundongos , Pessoa de Meia-Idade , Metástase Neoplásica/imunologia , Metástase Neoplásica/terapia , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/imunologia , RNA-Seq , Fator de Transcrição STAT6/genética , Fator de Transcrição STAT6/imunologia , Análise de Célula Única , Fator de Crescimento Transformador beta/genética
10.
Cell Mol Gastroenterol Hepatol ; 12(1): 251-276, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33652118

RESUMO

BACKGROUND & AIMS: The circadian clock is crucial for physiological homeostasis including gut homeostasis. Disorder of the circadian clock may contribute to many diseases including inflammatory bowel disease (IBD). However, the role and the mechanisms of circadian clock involvement in IBD still are unclear. METHODS: Disorder of the circadian clock including chronic social jet lag and circadian clock gene deficiency mice (Bmal1-/-, and Per1-/-Per2-/-) were established. Dextran sulfate sodium (DSS) and/or azoxymethane were used to induce mouse models of colitis and its associated colorectal cancer. Flow cytometry, immunohistochemistry, immunofluorescence, Western blot, and reverse-transcription quantitative polymerase chain reaction were used to analyze the characteristics of immune cells and their related molecules. RESULTS: Mice with disorders of the circadian clock including chronic social jet lag and circadian clock gene deficiency were susceptible to colitis. Functionally, regulatory B (Breg) cells highly expressing Programmed cell death 1 ligand 1 (PDL1) in intestinal intraepithelial lymphocytes (IELs) helped to alleviate the severity of colitis after DSS treatment and was dysregulated in DSS-treated Bmal1-/- mice. Notably, interleukin 33 in the intestinal microenvironment was key for Bmal1-regulated PDL1+ Breg cells and interleukin 33 was a target of Bmal1 transcriptionally. Dysregulated PDL1+ B cells induced cell death of activated CD4+ T cells in DSS-treated Bmal1-/- mice. Consequently, circadian clock disorder was characterized as decreased numbers of Breg+ PDL1+ cells in IELs and dysfunction of CD4+ T cells promoted colitis-associated colorectal cancer (CRC) in mice. In clinical samples from CRC patients, low expression of Bmal1 gene in paracancerous tissues and center area of tumor was associated closely with a poorer prognosis of CRC patients. CONCLUSIONS: Our study uncovers the importance of the circadian clock regulating PDL1+ Breg+ cells of IELs in IBD and IBD-associated CRC.


Assuntos
Linfócitos B/metabolismo , Antígeno B7-H1/metabolismo , Relógios Circadianos/genética , Neoplasias Associadas a Colite/metabolismo , Colite/metabolismo , Animais , Apoptose , Antígeno B7-H1/genética , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/patologia , Colite/patologia , Neoplasias Associadas a Colite/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
11.
Dalton Trans ; 49(4): 998-1001, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31930274

RESUMO

Reversible single crystal-to-single crystal transformations from [FeL2(NCS)2]·3MeOH (1·3MeOH, L = 2-(anthracen-10-yl)-1H-imidazo[4,5-f][1,10]phenanthroline) to 1 and 1·2H2O were reported, which were accompanied by on-off switching of the spin-crossover properties.

12.
Int J Biol Macromol ; 118(Pt B): 1501-1510, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30170363

RESUMO

Polysaccharides are the main active component of the Mongolian medicine Fructus Meliae Toosendan, but their effective extraction and antioxidant effects have not been reported. Therefore, the optimization of the microwave extraction of polysaccharides from Fructus Meliae Toosendan (FMTP) using the response interface method was carried out. Single-factor tests on four main factors (the solid-liquid ratio, microwave power, extraction time, and number of extractions) affecting the polysaccharide extraction rate in the microwave extraction process were carried out. Then, using the FMTP content as a response index, central composite tests on the four factors were conducted, and an optimization analysis using the response surface method was completed. Consequently, we obtained the optimum conditions for FMTP microwave extraction: a solvent-material ratio of 30.00 mL/mg, extraction power of 700 W, extraction time of 20 min, and two extractions. The FMTP extraction rate was 15.75% at the optimum conditions, consistent with the theoretical predictions. The crude polysaccharide was further purified to obtain high-purity FMTP polysaccharide, having a weight-average molecular mass of 1288 Da. The antioxidant activities of FMTP were evaluated using the hydroxyl superoxide anion, 2,2-diphenyl-1-picrylhydrazyl (DPPH), and nitrite free radical scavenging assays and reducing power assay. The data show that FMTP has considerable antioxidant activity. Thus, polysaccharides from Fructus Meliae Toosendan could be used as a potential antioxidant agent in medicine or as a functional food.


Assuntos
Fracionamento Químico/métodos , Frutas/química , Meliaceae/química , Micro-Ondas , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Antioxidantes/química , Antioxidantes/isolamento & purificação , Radical Hidroxila/química , Peso Molecular , Superóxidos/química
13.
Oncotarget ; 9(15): 12035-12049, 2018 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-29552291

RESUMO

The pathogenesis and key functional molecules involved in inflammatory bowel disease (IBD) including Crohn's disease (CD) and ulcerative colitis (UC) remain unclear. Here, we reported that Erbin, a protein required for the polarity of epithelial cells, is conserved across species and highly expressed in the intestinal mucosa in mice and zebrafish. Pathologically, Erbin expression in the intestinal mucosa was significantly decreased in DSS induced acute colitis mice, IL-10 deficient mice and clinical biopsy specimens from patients with ulcerative colitis. Moreover, Erbin deficient mice are more susceptible to experimental colitis, exhibiting more severe intestinal barrier disruption, with increased histological scores and excessive production of proinflammatory cytokines. Mechanistically, Erbin deficiency or knockdown significantly exacerbated activation of autophagic program and autophagic cell death in vivo and in vitro. And, inhibition of autophagy by Chloroquine attenuates excessive inflammatory response in the DSS-induced colitis mouse model of Erbin deletion. Generally, our study uncovers a crucial role of Erbin in autophagic cell death and IBD, giving rise to a new strategy for IBD therapy by inhibiting excessive activation of autophagy and autophagic cell death.

14.
Ying Yong Sheng Tai Xue Bao ; 22(11): 3073-80, 2011 Nov.
Artigo em Zh | MEDLINE | ID: mdl-22303690

RESUMO

Baseflow separation research is regarded as one of the most important and difficult issues in hydrology and ecohydrology, but lacked of unified standards in the concepts and methods. This paper introduced the theories of baseflow separation based on the definitions of baseflow components, and analyzed the development course of different baseflow separation methods. Among the methods developed, graph separation method is simple and applicable but arbitrary, balance method accords with hydrological mechanism but is difficult in application, whereas time series separation method and isotopic method can overcome the subjective and arbitrary defects caused by graph separation method, and thus can obtain the baseflow procedure quickly and efficiently. In recent years, hydrological modeling, digital filtering, and isotopic method are the main methods used for baseflow separation.


Assuntos
Ecossistema , Água Subterrânea , Hidrologia/métodos , Chuva , Movimentos da Água , Simulação por Computador , Isótopos/análise , Isótopos/química , Modelos Teóricos , Rios
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