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1.
Mol Med Rep ; 28(3)2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37449526

RESUMO

Adipose tissue­derived mesenchymal stem cells (ADMSCs) differentiate into cardiomyocytes and may be an ideal cell source for myocardial regenerative medicine. Ghrelin is a gastric­secreted peptide hormone involved in the multilineage differentiation of MSCs. To the best of our knowledge, however, the role and potential downstream regulatory mechanism of ghrelin in cardiomyocyte differentiation of ADMSCs is still unknown. The mRNA and protein levels were measured by reverse transcription­quantitative PCR and western blotting. Immunofluorescence staining was used to show the expression and cellular localization of cardiomyocyte markers and ß­catenin. RNA sequencing was used to explore the differentially expressed genes (DEGs) that regulated by ghrelin. The present study found that ghrelin promoted cardiomyocyte differentiation of ADMSCs in a concentration­dependent manner, as shown by increased levels of cardiomyocyte markers GATA binding protein 4, α­myosin heavy chain (α­MHC), ISL LIM homeobox 1, NK2 homeobox 5 and troponin T2, cardiac type. Ghrelin increased ß­catenin accumulation in nucleus and decreased the protein expression of secreted frizzled­related protein 4 (SFRP4), an inhibitor of Wnt signaling. RNA sequencing was used to determine the DEGs regulated by ghrelin. Functional enrichment showed that DEGs were more enriched in cardiomyocyte differentiation­associated terms and Wnt pathways. Dead­box helicase 17 (DDX17), an upregulated DEG, showed enhanced mRNA and protein expression levels following ghrelin addition. Overexpression of DDX17 promoted protein expression of cardiac­specific markers and ß­catenin and enhanced the fluorescence intensity of α­MHC and ß­catenin. DDX17 upregulation inhibited protein expression of SFRP4. Rescue assay confirmed that the addition of SFRP4 partially reversed ghrelin­enhanced protein levels of cardiac­specific markers and the fluorescence intensity of α­MHC. In conclusion, ghrelin promoted cardiomyocyte differentiation of ADMSCs by DDX17­mediated regulation of the SFRP4/Wnt/ß­catenin axis.


Assuntos
Células-Tronco Mesenquimais , Miócitos Cardíacos , Miócitos Cardíacos/metabolismo , Grelina/farmacologia , Grelina/metabolismo , beta Catenina/genética , beta Catenina/metabolismo , Diferenciação Celular/genética , Células-Tronco Mesenquimais/metabolismo , Via de Sinalização Wnt , RNA Mensageiro/metabolismo
2.
Toxicol Appl Pharmacol ; 475: 116635, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37487937

RESUMO

To explore the potential value of serum glutamate dehydrogenase (GLDH) combined with inflammatory cytokines as diagnostic biomarkers for anti-tuberculosis drug -induced liver injury (ATB-DILI). We collected the residual serum from the patients who met the criteria after liver function tests. We have examined these parameters including GLDH which were determined by enzyme-linked immunosorbent assay and cytokines which were determined by cytokine combination detection kit. Multivariate logistics stepwise forward regression was applied to establish regression models. A total of 138 tuberculosis patients were included in the diagnostic markers study of ATB-DILI, including normal liver function group (n = 108) and ATB-DILI group(n = 30). Serum GLDH, IL-6 and IL-10 levels were significantly increased in the ATB-DILI group. Receiver operating characteristic curve (ROC) curve showed that the area under curve (AUC) of serum GLDH, IL-6 and IL-10 for the diagnosis of ATB-DILI were 0.870, 0.714 and 0.811, respectively. In logistic regression modeling, the AUC of GLDH combined with IL-10 as an ATB-DILI marker is 0.912. Serum IL-6、IL-10 and GLDH levels began to rise preceded the increase in ALT by 7 days, with significant differences in IL-6 compared with 7 days. Serum GLDH, IL-6 and IL-10 levels were correlated with the severity of liver injury. In conclusion, we found that GLDH, IL-6 and IL-10 alone as diagnostic markers of ATB-DILI had good diagnostic efficacy. Logistic regression model established by GLDH and IL-10 had better diagnostic efficacy and IL-6 may be an early predictor of liver injury in the setting of ATB poisoning.


Assuntos
Doença Hepática Crônica Induzida por Substâncias e Drogas , Doença Hepática Induzida por Substâncias e Drogas , Humanos , Glutamato Desidrogenase , Interleucina-10 , Interleucina-6 , Biomarcadores , Citocinas , Doença Hepática Induzida por Substâncias e Drogas/diagnóstico , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Antituberculosos/efeitos adversos
3.
Biomed Environ Sci ; 35(10): 921-930, 2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36443269

RESUMO

Objective: The relationship between sodium intake and cardiovascular (CV) events remains unconfirmed. Therefore, we carried out a systematic review and dose-response meta-analysis for evaluating the potential impact of 24-hour sodium excretion on CV risk. Besides, 24-hour sodium excretion was used to replace daily sodium diet intake. Methods: We searched ISI Web of Science, Embase, PubMed, and the Cochrane Library. Our study included cohort studies reporting hazard ratio ( HR). The random-effects model was used for summarizing the total relative risks ( RRs) between the included studies. In addition, the generalized least-squares regression was employed to fit the study model. Results: A total of 9 studies involving 645,006 participants were included in this study. A significant non-linear relationship was observed between sodium excretion and CV events ( P non-linearity < 0.001). In studies collecting 24-h urine samples, the sodium excretion and CV events risk were associated linearly ( RR: 1.04; 95% CI: 1.01, 1.07). Conclusion: In a linear dose-response manner, every 1 g increase in sodium intake was associated with an increased risk of CV events up to 4%. Further studies are required to validate our conclusions further.


Assuntos
Doenças Cardiovasculares , Sódio na Dieta , Humanos , Urinálise , Radioisótopos de Sódio , Doenças Cardiovasculares/epidemiologia , Sódio na Dieta/efeitos adversos
4.
Dalton Trans ; 47(24): 8158-8163, 2018 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-29882946

RESUMO

Four phenylphosphonate-stabilized titanium-oxo clusters with varying functional ligands, namely, [Ti8(µ3-O)2(µ2-O)2(µ2-OiPr)4(OiPr)8(O3PC6H5)4(cat)2] (cat = catecholate), [Ti8(µ3-O)2(µ2-O)2(µ2-OiPr)4(OiPr)8(O3PC6H5)4(O2C10H6)2] (O2C10H6 = naphthalene-2,3-diolate), [Ti6(µ3-O)2(µ2-O)2(µ2-OiPr)4(OiPr)6(O3PC6H5)2(4-DMAB)2] (4-DMAB = 4-dimethylaminobenzoate), and [Ti6(µ3-O)2(µ2-O)2(µ2-OiPr)4(OiPr)6(O3PC6H5)2(4-CBA)2] (4-CBA = 4-cyanobenzoate) were synthesized and structurally characterized. The introduction of catecholate ligands effectively extended the visible absorption region up to 670 nm and reduced the band gap to 2.1 eV. DFT calculations revealed that the ligand-based energy levels could effectively modify the band structure of titanium-oxo clusters. The ligand-to-core charge transfer (LCCT) transition from the functional ligands to the cluster core is responsible for the low-energy charge transfer states. Photoelectrochemical and photocatalytic experiments show that functional ligands have significant influence on the physicochemical properties of titanium-oxo clusters.

5.
Inorg Chem ; 56(21): 12775-12782, 2017 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-29027802

RESUMO

The metal-to-core charge transfer (MCCT) transition in sensitized titanium-oxo clusters is an important process for photoinduced electron injection in photovoltaic conversion. This process resembles most closely the Type II photoinjection in dye-sensitized solar cells. Herein we report the synthesis and photophysical and photoelectrochemical (PEC) properties of the phosphonate-stabilized titanium-oxo clusters containing the ferrocenecarboxylate ligands. These ferrocene-containing clusters exhibit intense visible absorption extended up to 600 nm along with low optical band gaps of ∼2.2 eV. The low-energy transitions of these clusters were systematically investigated by UV-vis spectroscopy and DFT/TDDFT calculations. The combined experimental and computational studies suggest that the ferrocenecarboxylate-substituted titanium-oxo clusters form a donor-acceptor (D-A) system. The low-energy transition of these clusters primarily involves the MCCT from the iron center to TiO cluster core. The TiO core structure and phosphonate ligands both have great influence on the PEC properties of the clusters. This work provides valuable examples for the sensitized titanium-oxo clusters in which electron injection takes place via MCCT transition.

6.
Dalton Trans ; 46(36): 12313-12319, 2017 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-28884172

RESUMO

Organic donor-π-bridge-acceptor (D-π-A) dyes with arylamines as an electron donor have been widely used as photosensitizers for dye-sensitized solar cells (DSSCs). However, titanium-oxo clusters (TOCs) functionalized with this kind of D-π-A structured dye-molecule have rarely been explored. In the present study, the 4-dimethylaminobenzoate-functionalized titanium-oxo cluster [Ti6(µ3-O)6(OiPr)6(DMABA)6]·2C6H5CH3 (DMABA = 4-dimethylaminobenzoate) was synthesized and structurally characterized by single-crystal X-ray diffraction. For comparison, two other Ti6-oxo clusters, namely [Ti6(µ3-O)6(OiPr)6(AD)6] (AD = 1-adamantanecarboxylate) and [Ti6(µ3-O)2(µ2-O)(µ2-OiPr)4(OiPr)10(DMM)2] (DMM = dimethylmalonate), were also studied. The DMABA-functionalized cluster exhibits a remarkably reduced band gap of ∼2.5 eV and much enhanced photocurrent response in comparison with the other two clusters. The electronic structures and electronic transitions of the clusters were studied by DFT and TDDFT calculations. The computational results suggest that the low-energy transitions of the DMABA-functionalized cluster have a substantial charge-transfer character arising from the DMABA → {Ti6} cluster core ligand-to-core charge transfer (LCCT), along with the DMABA-based intra-ligand charge transfer (ILCT). These low-energy charge transfer transitions provide efficient electron injection pathways for photon-to-electron conversion.

7.
ACS Nano ; 11(9): 9143-9150, 2017 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-28787570

RESUMO

Diverse diode characteristics were observed in two-dimensional (2D) black phosphorus (BP) and molybdenum disulfide (MoS2) heterojunctions. The characteristics of a backward rectifying diode, a Zener diode, and a forward rectifying diode were obtained from the heterojunction through thickness modulation of the BP flake or back gate modulation. Moreover, a tunnel diode with a precursor to negative differential resistance can be realized by applying dual gating with a solid polymer electrolyte layer as a top gate dielectric material. Interestingly, a steep subthreshold swing of 55 mV/dec was achieved in a top-gated 2D BP-MoS2 junction. Our simple device architecture and chemical doping-free processing guaranteed the device quality. This work helps us understand the fundamentals of tunneling in 2D semiconductor heterostructures and shows great potential in future applications in integrated low-power circuits.

8.
Nat Commun ; 6: 6564, 2015 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-25800613

RESUMO

Semiconducting two-dimensional crystals are currently receiving significant attention because of their great potential to be an ultrathin body for efficient electrostatic modulation, which enables to overcome the limitations of silicon technology. Here we report that, as a key building block for two-dimensional semiconductor devices, vertical p-n junctions are fabricated in ultrathin MoS2 by introducing AuCl3 and benzyl viologen dopants. Unlike usual unipolar MoS2, the MoS2 p-n junctions show ambipolar carrier transport, current rectification via modulation of potential barrier in films thicker than 8 nm and reversed current rectification via tunnelling in films thinner than 8 nm. The ultimate thinness of the vertical p-n homogeneous junctions in MoS2 is experimentally found to be 3 nm, and the chemical doping depth is found to be 1.5 nm. The ultrathin MoS2 p-n junctions present a significant potential of the two-dimensional crystals for flexible, transparent, high-efficiency electronic and optoelectronic applications.

9.
Sci Rep ; 4: 4041, 2014 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-24509565

RESUMO

A gate-controlled metal-semiconductor barrier modulation and its effect on carrier transport were investigated in two-dimensional (2D) transition metal dichalcogenide (TMDC) field effect transistors (FETs). A strong photoresponse was observed in both unipolar MoS2 and ambipolar WSe2 FETs (i) at the high drain voltage due to a high electric field along the channel for separating photo-excited charge carriers and (ii) at the certain gate voltage due to the optimized barriers for the collection of photo-excited charge carriers at metal contacts. The effective barrier height between Ti/Au and TMDCs was estimated by a low temperature measurement. An ohmic contact behavior and drain-induced barrier lowering (DIBL) were clearly observed in MoS2 FET. In contrast, a Schottky-to-ohmic contact transition was observed in WSe2 FET as the gate voltage increases, due to the change of majority carrier transport from holes to electrons. The gate-dependent barrier modulation effectively controls the carrier transport, demonstrating its great potential in 2D TMDCs for electronic and optoelectronic applications.

10.
Histol Histopathol ; 29(3): 343-51, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23996810

RESUMO

AIMS: Gastric hyperplastic polyps (GHPs) are the most common polypoid lesion of the stomach, and their malignant potential has been demonstrated. In the present study, we evaluated the mucin phenotypes of GHPs and investigated the relationships among mucin phenotypes and clinical-pathological factors, proliferative activity and p53 expression in GHPs. METHODS: The CD10, MUC2, MUC5AC and MUC6 expression patterns of 238 GHPs were examined by immunohistochemical staining. The GHP mucin phenotypes were divided into 4 subtypes: the gastric mucin phenotype (G-type), the intestinal mucin phenotype (I-type), the mixed or gastrointestinal mucin phenotype (GI-type) and the unclassified mucin phenotype (U-type). RESULTS: The G and GI types were observed in 58% and 42% of the GHPs, respectively. However, no I or U type GHPs were found in the present study. The GI type was more common in lesions with dysplasia or carcinoma than in polyps without dysplasia or carcinoma (P<0.001). P53-positivity rate and high index of Ki-67 tumors were significantly more common in the GI-type than in the G-type polyps (P<0.001). CONCLUSIONS: The mucin phenotype may serve as a useful marker for the malignant potential of GHPs, and GI-type GHPs should be considered to be a lesion with malignant potential.


Assuntos
Proliferação de Células , Mucinas/metabolismo , Pólipos/metabolismo , Pólipos/patologia , Gastropatias/metabolismo , Gastropatias/patologia , Biomarcadores Tumorais/análise , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Fenótipo , Lesões Pré-Cancerosas/metabolismo , Lesões Pré-Cancerosas/patologia , Proteína Supressora de Tumor p53/metabolismo
11.
Nanotechnology ; 24(17): 175402, 2013 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-23558434

RESUMO

A tandem device which integrates a PVDF nanogenerator and silicon (Si) nanopillar solar cell is fabricated. The Si nanopillar solar cell was fabricated using a mask-free plasma etching technique and annealing process. The PVDF nanogenerator was stacked on top of the Si nanopillar solar cell using a spinning method. The optical properties and the device performance of nanowire solar cells have been characterized, and the dependence of device performance versus annealing time or method has been investigated. Furthermore, the PVDF nanogenerator was operated with a 100 dB sound wave and a 0.8 V peak to peak output voltage was generated. This tandem device can successfully harvest energy from both sound vibration and solar light, demonstrating its strong potential as a future ubiquitous energy harvester.

12.
Appl Microbiol Biotechnol ; 95(3): 811-21, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22159733

RESUMO

Based on preliminary investigation of microbial populations in a high pour-point oil reservoir, an indigenous microbial enhanced oil recovery (MEOR) field trial was carried out. The purpose of the study is to reveal the impact of the indigenous MEOR process on microbial community structure in the oil reservoir using 16Sr DNA clone library technique. The detailed monitoring results showed significant response of microbial communities during the field trial and large discrepancies of stimulated microorganisms in the laboratory and in the natural oil reservoir. More specifically, after nutrients injection, the original dominant populations of Petrobacter and Alishewanella in the production wells almost disappeared. The expected desirable population of Pseudomonas aeruginosa, determined by enrichment experiments in laboratory, was stimulated successfully in two wells of the five monitored wells. Unexpectedly, another potential population of Pseudomonas pseudoalcaligenes which were not detected in the enrichment culture in laboratory was stimulated in the other three monitored production wells. In this study, monitoring of microbial community displayed a comprehensive alteration of microbial populations during the field trial to remedy the deficiency of culture-dependent monitoring methods. The results would help to develop and apply more MEOR processes.


Assuntos
Biota , Campos de Petróleo e Gás/microbiologia , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
13.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 9): o1690, 2008 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-21201679

RESUMO

In the crystal structure, the title compound, C(12)H(16)N(6)O(6), lies on an inversion centre. The mol-ecule has an anti-periplanar conformation with respect to the C-C bond of the central ethane unit and the two imidazole rings are parallel to each other. The dihedral angle between the imidazole ring and the mean plane of the C and O atoms of the bis-(eth-oxy)ethane group is 76.04 (6)°. The mol-ecules are stacked along the c axis through a weak C-H⋯O inter-action and a π⋯π inter-action between the imidazole rings with a centroid-centroid distance of 3.5162 (6) Å. An intramolecular C-H⋯O hydrogen bond is also present.

14.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 8): o1409, 2008 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-21203129

RESUMO

In the crystal structure of the title compound, C(20)H(16)O(4), the naphthalene ring system makes dihedral angles of 43.79 (7) and 83.70 (9)°, respectively, with the mean planes of the phenyl ring and the acetate unit. C-H⋯π inter-actions involving all the aromatic six-membered rings are observed. The mol-ecules are stacked into columns along the a axis and adjacent columns are linked by weak C-H⋯O inter-actions.

15.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 8): o1472-3, 2008 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-21203186

RESUMO

IN THE TITLE COMPOUND [SYSTEMATIC NAME: (tert-butyl-dimethyl-silyl)methane-triyl tris-(4-methyl-benzene-sulfonate)], C(32)H(44)O(10)S(3)Si, the central C atom and the Si(IV) center are in a tetra-hedral configuration. The inter-planar angles between pairs of the three benzene rings of the 4-methyl-phenyl-sulfonyl units are 41.15 (10), 18.11 (10) and 44.09 (10)°. C-H⋯π inter-actions are observed in the crystal structure. Mol-ecules are linked into screw chains along the b axis by weak C-H⋯O inter-actions. Weak intramolecular C-H⋯O hydrogen bonds are also present.

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