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1.
Chemphyschem ; 25(19): e202400488, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39005001

RESUMEN

In a recent paper (ChemPhysChem, 2023, 24, e202200947), based on the results computed using DFT method, the perfect core-shell octahedral configuration Be@B38 and Zn@B38 was reported to be the global minima of the MB38(M=Be and Zn) clusters. However, this paper presents the lower energy structures of MB38(M=Be and Zn) clusters as a quasi-planar configuration, the Be atom is found to reside on the convex surface of the quasi-planar B38 isomer, while the Zn atom tends to be attached to the top three B atoms of the quasi-planar B38 isomer. Our results show that quasi-planar MB38(M=Be and Zn) at DFT method have lower energy than core-shell octahedral configuration M@B38(M=Be and Zn). Natural atomic charges, valence electron density, electron localization function (ELF) analyses identify the MB38(M=Be and Zn) to be charge transfer complexes (Be2+B38 2-and Zn1+B38 1-) and suggest primarily the electrostatic interactions between doped atom and B38 fragment. The photoelectron spectra of the corresponding anionic structures were simulated, providing theoretical basis for future structural identification.

2.
ACS Omega ; 8(47): 44831-44838, 2023 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-38046297

RESUMEN

A new kind of nonmetallic atom-doped boron cluster is described herein theoretically. When a phosphorus atom is added to the B12 motif and loses an electron, a novel B12 cage is obtained, composed of two B3 rings at both ends and one B6 ring in the middle, forming a triangular bifrustum. Interestingly, this B12 cage is formed by three B7 units joined together from three directions at an angle of 120°. When two P atoms are added to the B12 motif, this novel B12 cage is also obtained, and two P atoms are attached to the B3 rings at both ends of the triangular bifrustum, forming a triangular bipyramid (Johnson solid). Amazingly, the global minimums of neutral, monocationic, and monoanionic P2B12+/0/- have the same cage structure with a D3h symmetry; this is the smallest boron cage with the same structure. The P atom has five valence electrons, according to adaptive natural density partitioning bonding analyses of cage PB12+ and P2B12, in addition to one lone pair, the other three electrons of the P atom combine with an electron of each B atom on the B3 ring to form three 2c-2e σ bonds and form three electron sharing bonds with B atoms through covalent interactions, stabilizing the B12 cage. The calculated photoelectron spectra can be compared with future experimental values and provide a theoretical basis for the identification and confirmation of PnB12- (n = 1-2).

3.
ACS Omega ; 8(33): 30757-30767, 2023 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-37636960

RESUMEN

We present a theoretical study of structural evolution, electronic properties, and photoelectron spectra of two sulfur atom-doped boron clusters S2Bn0/- (n = 2-13), which reveal that the global minima of the S2Bn0/- (n = 2-13) clusters show an evolution from a linear-chain structure to a planar or quasi-planar structure. Some S-doped boron clusters have the skeleton of corresponding pure boron clusters; however, the addition of two sulfur atoms modified and improved some of the pure boron cluster structures. Boron is electron-deficient and boron clusters do not form linear chains. Here, two sulfur atom doping can adjust the pure boron clusters to a linear-chain structure (S2B20/-, S2B30/-, and S2B4-), a quasi-linear-chain structure (S2B6-), single- and double-chain structures (S2B6 and S2B9-), and double-chain structures (S2B5, and S2B9). In particular, the smallest linear-chain boron clusters S2B20/- are shown with an S atom attached to each end of B2. The S2B2 cluster possesses the largest highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbital (LUMO) gap of 5.57 eV and the S2B2- cluster possesses the largest average binding energy Eb of 5.63 eV, which shows the superior chemical stability and relative stability, respectively. Interestingly, two S-atom doping can adjust the quasi-planar pure boron clusters (B7-, B10-, and B120/-) to a perfect planar structure. AdNDP bonding analyses reveal that linear S2B3 and planar SeB11- have π aromaticity and σ antiaromaticity; however, S2B2, planar S2B6, and planar S2B7- clusters have π antiaromaticity and σ aromaticity. Furthermore, AdNDP bonding analyses reveal that planar S2B4, S2B10, and S2B12 clusters are doubly (π and σ) aromatic, whereas S2B5-, S2B8, S2B9-, and S2B13- clusters are doubly (π and σ) antiaromatic. The electron localization function (ELF) analysis shows that S2Bn0/- (n = 2-13) clusters have different electron delocalization characteristics, and the spin density analysis shows that the open-shell clusters have different characteristics of electron spin distribution. The calculated photoelectron spectra indicate that S2Bn- (n = 2-13) have different characteristic peaks that can be compared with future experimental values and provide a theoretical basis for the identification and confirmation of these doped boron clusters. Our work enriches the new database of geometrical structures of doped boron clusters, provides new examples of aromaticity for doped boron clusters, and is promising to offer new ideas for nanomaterials and nanodevices.

4.
J Chromatogr A ; 1697: 463988, 2023 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-37071965

RESUMEN

Construction of different surface wettability is meaningful for the interaction between the sorbent surface and target components. In the current study, four kinds of stainless-steel wires (SSWs) with different hydrophobic/hydrophilic property were prepared and used as the absorbents to enrich the target compounds with different polarity. Comparative extraction of six non-polar polycyclic aromatic hydrocarbons (PAHs) and six polar estrogens was carried out by in-tube solid phase microextraction (IT-SPME). The results showed that two SSWs with the superhydrophobic surfaces exhibited high extraction capacity to the non-polar PAHs with the superior enrichment factor (EF) in the range of 29-672 and 57-744, respectively. In contrast, the superhydrophilic SSWs demonstrated higher enrichment efficiency for the polar estrogens than other hydrophobic SSWs. On the basis of optimized conditions, a validated analysis method was established using six PAHs as model analytes for IT-SPME-HPLC. Acceptable linear ranges (0.5-10 µg L-1) and low detection limits (0.0056-0.32 µg L-1) were achieved using the superhydrophobic wire modified by perfluorooctyl trichlorosilane (FOTS). The relative recoveries spiked at 2, 5 and 10 µg L-1 in the lake water samples were in the range of 81.5%-113.7%. The relative standard deviation (RSD) of intraday (≤0.8%, n = 3) and interday (≤5.3%, n = 3) tests demonstrated the good extraction repeatability for the same extraction tube. Satisfactory repeatability for the preparation of extraction tubes (n = 3) was also obtained with the RSD values in the range of 3.6%-8.0%.


Asunto(s)
Hidrocarburos Policíclicos Aromáticos , Microextracción en Fase Sólida , Microextracción en Fase Sólida/métodos , Acero Inoxidable/química , Hidrocarburos Policíclicos Aromáticos/análisis , Estrógenos
5.
Molecules ; 28(1)2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36615549

RESUMEN

A theoretical research of structural evolution, electronic properties, and photoelectron spectra of selenium-doped boron clusters SeBn0/- (n = 3-16) is performed using particle swarm optimization (CALYPSO) software in combination with density functional theory calculations. The lowest energy structures of SeBn0/- (n = 3-16) clusters tend to form quasi-planar or planar structures. Some selenium-doped boron clusters keep a skeleton of the corresponding pure boron clusters; however, the addition of a Se atom modified and improved some of the pure boron cluster structures. In particular, the Se atoms of SeB7-, SeB8-, SeB10-, and SeB12- are connected to the pure quasi-planar B7-, B8-, B10-, and B12- clusters, which leads to planar SeB7-, SeB8-, SeB10-, and SeB12-, respectively. Interestingly, the lowest energy structure of SeB9- is a three-dimensional mushroom-shaped structure, and the SeB9- cluster displays the largest HOMO-LUMO gap of 5.08 eV, which shows the superior chemical stability. Adaptive natural density partitioning (AdNDP) bonding analysis reveals that SeB8 is doubly aromatic, with 6 delocalized π electrons and 6 delocalized σ electrons, whereas SeB9- is doubly antiaromatic, with 4 delocalized π electrons and 12 delocalized σ electrons. Similarly, quasi-planar SeB12 is doubly aromatic, with 6 delocalized π electrons and 14 delocalized σ electrons. The electron localization function (ELF) analysis shows that SeBn0/- (n = 3-16) clusters have different local electron delocalization and whole electron delocalization effects. The simulated photoelectron spectra of SeBn- (n = 3-16) have different characteristic bands that can identify and confirm SeBn- (n = 3-16) combined with future experimental photoelectron spectra. Our research enriches the geometrical structures of small doped boron clusters and can offer insight for boron-based nanomaterials.

6.
Small ; 19(9): e2205246, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36581560

RESUMEN

Boosting charge separation and transfer of photoanodes is crucial for providing high viability of photoelectrochemical hydrogen (H2 ) generation. Here, a structural engineering strategy is designed and synthesized for uniformly coating an ultrathin CoFe bimetal-organic framework (CoFe MOF) layer over a BiVO4 photoanode for boosted charge separation and transfer. The photocurrent density of the optimized BiVO4 /CoFe MOF(NA) photoanode reaches a value of 3.92 mA cm-2 at 1.23 V versus reversible hydrogen electrode (RHE), up to 6.03 times that of pristine BiVO4 , due to the greatly increased efficiency of charge transfer and separation. In addition, this photoanode records one onset potential that is considerably shifted negatively when compared to BiVO4 . Transient absorption spectroscopy reveals that the CoFe MOF(NA) prolongs charge recombination lifetime by blocking the hole-transfer pathway from the BiVO4 to its surface trap states. This work sheds light on boosting charge separation and transfer through structural engineering to enhance the photocurrent of photoanodes for solar H2 production.

7.
Membranes (Basel) ; 12(12)2022 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-36557097

RESUMEN

Water/oil separation from their mixture and emulsion has been a prominent topic in fundamental research and in practical applications. In this work, a smart superhydrophobic membrane (SHP) was obtained by dipping an off-the-shelf laboratory filter paper in an ethanol suspension of trichloro (1H,1H,2H,2H-tridecafluoro-n-octyl) silane, tetraethyl orthosilicate, and titanium dioxide nanoparticles with different dimensions of 20 and 100 nm. The selection of membrane substrates was optimized including different quantitative and quantitative filter papers with different filtration velocity (slow, intermediate, and fast). The as-prepared SHP was demonstrated to be superhydrophobic and photosensitive, which was used in the separation of carbon tetrachloride and water from their mixture and emulsion. Moreover, orderly aligned micropores were formed for the modified superhydrophobic filter papers by using nanosecond laser. Unidirectional penetration was obtained for the UV-irradiated paper with a bored pore in the range of 50-500 µm in the systems of air/water and water/oil. This study may promote the understanding of unidirectional transportation of liquid droplet and facilitate the design of interfacial materials with Janus-type wettability.

8.
ACS Omega ; 7(45): 41266-41274, 2022 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-36406576

RESUMEN

Here, the ground-state structures, electronic structures, polarizability, and spectral properties of metal-free phthalocyanine (H2Pc) under different external electric fields (EEFs) are investigated. The results show that EEF has an ultrastrong regulation effect on various aspects of H2Pc; the geometric structures, electronic properties, polarizability, and spectral properties are strongly sensitive to the EEF. In particular, an EEF of 0.025 a.u. is an important control point: an EEF of 0.025 a.u. will bend the benzene ring subunits to the positive and negative x directions of the planar molecule. Flipping the EEF from positive (0.025 a.u.) to negative (-0.025 a.u.) flips also the bending direction of benzene ring subunits. The H2Pc shows different dipole moments projecting an opposite direction along the x direction (-84 and 84 Debye for EEFs of -0.025 and 0.025 a.u., respectively) under negative and positive EEF, revealing a significant dipole moment transformation. Furthermore, when the EEF is removed, the molecule can be restored to the planar structure. The transformation of the H2Pc structure can be induced by the EEF, which has potential applications in the molecular devices such as molecular switches or molecular forceps. EEF lowers total energy and reduces highest occupied molecular orbital-lowest unoccupied molecular orbital (HOMO-LUMO) gap; especially, an EEF of 0.025 a.u. can reduce the HOMO-LUMO gap from 2.1 eV (in the absence of EEF) to 0.37 eV, and thus, it can enhance the molecular conductivity. The first hyperpolarizability of H2Pc is 0 in the absence of EEF; remarkably, an EEF of 0.025 a.u. can enhance the first hyperpolarizability up to 15,578 a.u. Therefore, H2Pc under the EEF could be introduced as a promising innovative nonlinear optical (NLO) nanomaterial such as NLO switches. The strong EEF (0.025 a.u.) causes a large number of new absorption peaks in IR and Raman spectra and causes the redshift of electronic absorption spectra. The changes of EEF can be used to regulate the structure transformation and properties of H2Pc, which can promote the application of H2Pc in nanometer fields such as molecular devices.

9.
Molecules ; 27(17)2022 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-36080387

RESUMEN

A robust superhydrophobic brass mesh was fabricated based on a low-energy surface and a roughness on the nano/micro-meter scale. It was carried out by the forming of hydroxyapatite (HP) coatings on its surface through a constant current electro-deposition process, followed by immersion in fluoroalkylsilane solution. Surface morphology, composition and wetting behavior were investigated by field-emission scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), high speed camera, and contact angle goniometer. Under optimal conditions, the resulting brass mesh exhibited superhydrophobicity, excellent anti-corrosion (η = 91.2%), and anti-scaling properties. While the surfactant liquid droplets of tetradecyl trimethyl ammonium bromide (TTAB) with different concentration were dropped on the superhydrophobic surface, maximum droplet rebounding heights and different contact angles (CAs) were observed and measured from side-view imaging. The plots of surfactant-concentration-maximum bounding height/CA were constructed to determine its critical-micelle-concentration (CMC) value. Close CMC results of 1.91 and 2.32 mM based on the determination of maximum rebounding height and CAs were obtained. Compared with its theoretical value of 2.1 mM, the relative errors are 9% and 10%, respectively. This indicated that the novel application based on the maximum rebounding height could be an alternative approach for the CMC determination of other surfactants.


Asunto(s)
Durapatita , Tensoactivos , Cobre , Durapatita/química , Propiedades de Superficie , Tensoactivos/química , Humectabilidad , Zinc
10.
RSC Adv ; 12(26): 16706-16716, 2022 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-35754907

RESUMEN

A theoretical study of geometrical structures, electronic properties, and spectral properties of single-atom transition metal-doped boron clusters MB24 - (M = Sc, Ti, V, Cr, Mn, Fe, Co, and Ni) is performed using the CALYPSO approach for the global minimum search, followed by density functional theory calculations. The global minima obtained for the MB24 - (M = Sc, Ti, V, and Cr) clusters correspond to cage structures, and the MB24 - (M = Mn, Fe, and Co) clusters have similar distorted four-ring tubes with six boron atoms each. Interestingly, the global minima obtained for the NiB24 - cluster tend to a quasi-planar structure. Charge population analyses and valence electron density analyses reveal that almost one electron on the transition-metal atoms transfers to the boron atoms. The electron localization function (ELF) of MB24 - (M = Sc, Ti, V, Cr, Mn, Fe, Co, and Ni) indicates that the local delocalization of MB24 - (M = Sc, Ti, V, Cr, and Ni) is weaker than that of MB24 - (M = Mn, Fe, and Co), and there is no obvious covalent bond between doped metal and B atoms. The spin density and spin population analyses reveal that open-shell MB24 - (M = Ti, Cr, Fe, and Ni) has different spin characteristics which are expected to lead to interesting magnetic properties and potential applications in molecular devices. The polarizability of MB24 - (M = Sc, Ti, V, Cr, Mn, Fe, Co, and Ni) shows that MB24 - (M = Mn, Fe, and Co) has larger first hyperpolarizability, indicating that MB24 - (M = Mn, Fe, and Co) has a strong nonlinear optical response. Hence, MB24 - (M = Mn, Fe, and Co) might be considered as a promising nonlinear optical boron-based nanomaterial. The calculated spectra indicate that MB24 - (M = Sc, Ti, V, Cr, Mn, Fe, Co, and Ni) has different and meaningful characteristic peaks that can be compared with future experimental values and provide a theoretical basis for the identification and confirmation of these single-atom transition metal-doped boron clusters. Our work enriches the database of geometrical structures of doped boron clusters and can provide an insight into new doped boron clusters.

11.
ACS Omega ; 6(45): 30442-30450, 2021 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-34805674

RESUMEN

A theoretical study of geometrical structures, electronic properties, and spectral properties of single-atom transition metal-doped boron clusters MB24 (M = Sc, V, and Mn) is performed using the CALYPSO approach for the global minimum search, followed by density functional theory calculations. The global minima obtained for the VB24 and MnB24 clusters correspond to cage structures. Interestingly, the global minima obtained for the ScB24 cluster tend to a three-ring tubular structure. Population analyses and valence electron density analyses reveal that partial electrons on transition-metal atoms transfer to boron atoms. The localized orbital locator of MB24 (M = Sc, V, and Mn) indicates that the electron delocalization of ScB24 is stronger than that of VB24 and MnB24, and there is no obvious covalent bond between doped metals and B atoms. The spin density and spin population analyses reveal that MB24 (M = Sc, V, and Mn) have different spin characteristics which are expected to lead to interesting magnetic properties and potential applications in molecular devices. The calculated spectra indicate that MB24 (M = Sc, V, and Mn) has meaningful characteristic peaks that can be compared with future experimental values and provide a theoretical basis for the identification and confirmation of these single-atom transition metal-doped boron clusters. Our work enriches the database of geometrical structures of doped boron clusters and can provide an insight into new doped boron clusters.

12.
Medicine (Baltimore) ; 100(7): e24845, 2021 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-33607855

RESUMEN

ABSTRACT: Despite the establishment of the links between ulcerative colitis (UC) and depression, between UC and gut microbiota, few correlations between depression and gut microbiota have yet been demonstrated especially in ulcerative colitis patients. The objective of our study was therefore to determine whether the comorbidity of depressive disorder in ulcerative colitis patients correlate with alterations in the gut microbiota and to identify the specific microbiota signatures associated with depression.Between March 2017 and February 2018, 31 healthy volunteers, 31 UC patients without depression, and 31 UC patients with depression from Longhua Hospital were enrolled. Clinical data and fecal samples were collected for each patient. Fecal bacteria were identified using 16 s rRNA sequencing. We compared microbial composition among the 3 groups using bioinformatic analysis.Patients with UC with depression had higher disease severity (P < .05). The UC without depression group had moderate reduction of microbial abundance and uniformity compared to the control group. The UC with depression group had the lowest microbial abundance. With regard to the vital bacteria in the microbiota-gut-brain axis, patients with UC and depression had the lowest abundance of Firmicutes, Clostridia, and Clostridiales but the highest abundance of Proteobacteria, Gammaproteobacteria, and Bacilli.The presence of depression in UC patients presented significant differences in the composition of gut microbiota compared with UC patients without depression, with increased abundance of Firmicutes and reduced abundance of Proteobacteria.


Asunto(s)
Colitis Ulcerosa/microbiología , Depresión/microbiología , Heces/microbiología , Microbioma Gastrointestinal/genética , Adulto , Bacterias/clasificación , Bacterias/genética , Bacterias/crecimiento & desarrollo , Estudios de Casos y Controles , Clostridiales/crecimiento & desarrollo , Colitis Ulcerosa/psicología , Comorbilidad , Biología Computacional/métodos , Depresión/complicaciones , Femenino , Firmicutes/crecimiento & desarrollo , Gammaproteobacteria/crecimiento & desarrollo , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Proteobacteria/crecimiento & desarrollo , ARN Ribosómico 16S/genética , Índice de Severidad de la Enfermedad
13.
ACS Omega ; 5(32): 20525-20534, 2020 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-32832805

RESUMEN

Structures and electronic properties of alkali metal atom-doped boron clusters MB12 0/- (M = Li, Na, K) are determined using the CALYPSO method for the global minimum search followed by density functional theory. It is found that the global minima obtained for the neutral clusters correspond to the half-sandwich structure and those of the monoanionic clusters correspond to the boat-shaped structure. The neutral MB12 (M = Li, Na, K) can be considered as a member of the half-sandwich doped B12 clusters, and the geometrical pattern of anion MB12 - (M = Li, Na, K) is a new structure that is different from other doped B12 clusters. Natural population and chemical bonding analyses reveal that the alkali metal atom-doped boron clusters MB12 - are characterized as charge transfer complexes, M+B12 2-, resulting in symmetrically distributed chemical bonds and electrostatic interactions between cationic M+ and boron atoms. The calculated spectra indicate that MB12 0/- (M = Li, Na, K) has meaningful spectral features that can be compared with future experimental data. Our work enriches the varieties of geometrical structures of doped boron clusters and can provide much insight into boron nanomaterials.

14.
ACS Omega ; 4(22): 20024-20035, 2019 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-31788637

RESUMEN

The electron-transport layer in planar perovskite solar cells plays an important role in improving photoelectric conversion efficiency. At present, the main electronic transmission materials in perovskite solar cells include TiO2, ZnO, WO3, ZrO2, SnO2, ZnO2, etc. This work mainly studies the electron-transport characteristics of six different electron-transport layers in perovskite solar cells. Based on the density functional theory, the electron-transport model of a solar cell doped with formamidinium iodide lead compound perovskite under six different electron-transport materials was constructed, and their effective electron mass and the mobility of carriers were obtained by optimizing the structure and theoretical calculation. The results show that the mobility of electrons in TiO2 crystal is slightly higher than that of FA0.75Cs0.25Sn0.5Pb0.5I3 carriers. Because of their high matching degree, it can be reasonably explained that titanium dioxide has been widely used in perovskite solar cells and achieved higher photoelectric conversion efficiency. In addition, the mobility of carriers in WO3 and SnO2 crystals is also high, so they also have great advantages in carrier transport. Due to its abundant, nontoxic, and low-pollution content, TiO2 has become the most widely used electronic transmission layer material for solar cells. Furthermore, we have explored eight new semiconductor materials that have not yet been used in perovskite solar cells as the electron-transport layer. The calculation results show that Ta2O5 and Bi2O3 are promising materials for the electron-transport layer. This study provides a theoretical basis for seeking better electronic transmission materials for solar cells in the future.

15.
Open Life Sci ; 14: 494-501, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33817185

RESUMEN

AIM: This study investigates the effect of astragalus polysaccharides (APS) in protecting against thapsigargin-induced endoplasmic reticulum (ER) stress in HT29 cells by suppressing the PERK-eIF2a signaling pathway. METHODS: HT29 cells were induced by thapsigargin for 12 hours, then treated with APS for 24 hours, and the gene expressions of GRP78, CHOP and eIF2a were quantified by reverse transcription quantitative polymerase chain reaction (RT-qPCR). The expression of GRP78, CHOP, PERK, p-PERK, eIF2a, and p-eIF2a were detected by Western blot. RESULTS: The ER stress caused by thapsigargin strongly up-regulated the expression of GRP78 and CHOP in HT29 cells, which activated the PERK-eIF2a pathway. There was an increase in PERK phosphorylation, and induction of eIF2a in HT29 cells. Thapsigargin caused significant ER expansion in HT29 cells due to the 12-hour ER stress. Importantly, Astragalus polysaccharide significantly inhibited the phosphorylation of PERK and eIF2a, which reduced the mRNA levels of GRP78, CHOP, PERK and eIF2a, and inhibited the ER expansion in HT29 cells after 24 hours of treatment. CONCLUSION: The results indicate that APS reduces the expression of GRP78 and CHOP in HT29 cells, at least in part, by preventing the activation of the PERK-eIF2a signaling pathway.

16.
World J Gastroenterol ; 23(26): 4724-4734, 2017 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-28765693

RESUMEN

AIM: To investigate the underlying effect of Jianpi Qingchang decoction (JQD) regulating intestinal motility of dextran sulfate sodium (DSS)-induced colitis in mice. METHODS: C57BL/6 mice were randomly divided into four groups: the control group, the DSS group, the JQD group, and the 5-aminosalicylic acid group. Except for the control group, colitis was induced in other groups by giving distilled water containing 5% DSS. Seven days after modeling, the mice were administered corresponding drugs intragastrically. The mice were sacrificed on the 15th day. The disease activity index, macroscopic and histopathologic lesions, and ultrastructure of colon interstitial cells of Cajal (ICC) were observed. The levels of tumor necrosis factor-alpha (TNF-α), interleukin (IL)-1ß, IL-10 and interferon gamma (IFN-γ), the expression of nuclear factor-kappa B (NF-κB) p65, c-kit, microtubule-associated protein 1 light chain 3 (LC3-II) and Beclin-l mRNA, and the colonic smooth muscle tension were assessed. RESULTS: Acute inflammation occurred in the mice administered DSS. Compared with the control group, the levels of IL-1ß, TNF-α, IL-10 and IFN-γ, the expression of LC3-II, Beclin-1 and NF-κB p65 mRNA, and the contractile frequency increased (P < 0.05), the expression of c-kit mRNA and the colonic smooth muscle contractile amplitude decreased in the DSS group (P < 0.05). Compared with the DSS group, the levels of IL-10 and IFN-γ, the expression of c-kit mRNA, and the colonic smooth muscle contractile amplitude increased (P < 0.05), the levels of TNF-α and IL-1ß, the expression of LC3-II, Beclin-1 and NF-κB p65 mRNA, and the contractile frequency decreased in the JQD group (P < 0.05). CONCLUSION: JQD can regulate the intestinal motility of DSS-induced colitis in mice through suppressing intestinal inflammatory cascade reaction, reducing autophagy of ICC, and regulating the network path of ICC/smooth muscle cells.


Asunto(s)
Autofagia/efectos de los fármacos , Colitis/tratamiento farmacológico , Medicamentos Herbarios Chinos/uso terapéutico , Motilidad Gastrointestinal/efectos de los fármacos , Células Intersticiales de Cajal/efectos de los fármacos , Animales , Colitis/inducido químicamente , Colitis/metabolismo , Colitis/patología , Colon/efectos de los fármacos , Colon/metabolismo , Colon/ultraestructura , Sulfato de Dextran , Evaluación Preclínica de Medicamentos , Medicamentos Herbarios Chinos/farmacología , Masculino , Ratones Endogámicos C57BL , Fitoterapia , Distribución Aleatoria , Índice de Severidad de la Enfermedad
17.
Medicine (Baltimore) ; 96(16): e6651, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28422869

RESUMEN

This study aims to determine the effects of the Jianpi Qingchang decoction (JQD) on the quality of life (QOL) of patients with spleen deficiency and dampness-heat syndrome ulcerative colitis (UC).A total of 120 active UC patients with spleen deficiency and dampness-heat syndrome were enrolled into this study. These patients were randomly divided into 2 groups: test group and control group (n = 60, each group). Patients in the test group were treated with JQD, while patients in control group were treated with 5-amino salicylic acid. After treatment for 8 weeks, differences in inflammatory bowel disease questionnaire (IBDQ) scores, short form-36 health survey questionnaire (SF-36) scores, and Sutherland Disease Activity Index (DAI) values were compared between these 2 groups to assess the QOL of patients.Sutherland DAI scores decreased in both groups after the treatment, but the difference was not statistically significant (P < .05). However, the difference in bowel symptoms, systemic symptoms, total scores of the 4 IBDQ dimensions (physical function, bodily pain, vitality, and mental health), and total scores of the SF-36 questionnaires between these 2 groups were statistically significant (P < .05).JQD can be used as supplementary and alternative therapy to relieve clinical symptoms in patients with mild to moderate active UC, and consequently improve their QOL.


Asunto(s)
Colitis Ulcerosa/complicaciones , Colitis Ulcerosa/tratamiento farmacológico , Medicamentos Herbarios Chinos/uso terapéutico , Fármacos Gastrointestinales/uso terapéutico , Calidad de Vida , Enfermedades del Bazo/complicaciones , Adulto , Femenino , Estado de Salud , Humanos , Masculino , Salud Mental , Mesalamina/uso terapéutico , Persona de Mediana Edad , Dolor/tratamiento farmacológico
18.
World J Gastroenterol ; 23(7): 1180-1188, 2017 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-28275298

RESUMEN

AIM: To investigate the therapeutic effect of Jianpi Qingchang decoction (JPQCD) on dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) in mice. METHODS: C57BL/c mice were injected intragastrically with 5% DSS instead of drinking water for 7 d, and their body weight, diarrhea severity and fecal bleeding were monitored, while the mice in the control group were treated with standard drinking water, without DSS. After 7 d, the DSS drinking water was changed to normal water and the DSS group continued with DSS water. The control and DSS groups were given normal saline by intragastric injection. The 5-aminosalicylic acid (5-ASA) group was treated orally with 5-ASA at a dose of 100 mg/kg daily. The JPQCD group was treated orally with JPQCD at a dose of 17.1 g/kg daily. On day 14, the colon length was measured, the colorectal histopathological damage score was assessed, and protein levels of interleukin (IL)-1ß, IL-8 and tumor necrosis factor-alpha (TNF-α) in colon supernatants were measured by enzyme-linked immunosorbent assay. mRNA expression of IL-1ß, IL-8, TNF-α and nuclear factor-kappa B (NF-κB) was detected by real-time quantitative polymerase chain reaction. Western blotting was used to detect the protein expression of NF-κB and inhibitor of kappa B. RESULTS: Acute inflammation occurred in the mice administered DSS, including the symptoms of losing body weight, loose feces/watery diarrhea and presence of fecal blood; all these symptoms worsened at 7 d. The colons of mice treated with DSS were assessed by histological examination, and the results confirmed that acute inflammation had occurred, as evidenced by loss of colonic mucosa and chronic inflammatory cell infiltration, and these features extended into the deeper layer of the colon walls. The expression levels of IL-1ß, IL-8 and TNF-α in the DSS group were higher than those in the control group (P < 0.05), and the expression levels of IL-1ß, IL-8 and TNF-α in the JPQCD and 5-ASA groups were lower than those in the DSS group after treating with JPQCD and 5-ASA. Comparing with the DSS group, the mRNA level of IL-1ß, IL-8, TNF-α and NF-κB was significantly reduced by 5-ASA and JPQCD. The difference between JPQCD and 5-ASA groups was not statistically significant (P > 0.05). Comparing with the DSS group, due to using JPQCD and 5-ASA, significant suppression of activation in DSS-induced NF-κB and increased phosphorylation of IκB in mice with experimental colitis occurred (P < 0.05). The difference between the JPQCD group and the 5-ASA group was not statistically significant (P > 0.05). CONCLUSION: Activation of the NF-κB signaling pathway is inhibited by JPQCD, which shows the potential mechanism by which JPQCD treats UC.


Asunto(s)
Colitis Ulcerosa/tratamiento farmacológico , Colitis/tratamiento farmacológico , Sulfato de Dextran/química , Medicamentos Herbarios Chinos/uso terapéutico , FN-kappa B/metabolismo , Animales , Colon/metabolismo , Inflamación , Interleucina-1beta/metabolismo , Interleucina-8/metabolismo , Masculino , Mesalamina/química , Ratones , Ratones Endogámicos C57BL , FN-kappa B/antagonistas & inhibidores , Transducción de Señal , Factor de Necrosis Tumoral alfa/metabolismo
19.
J Hum Genet ; 60(11): 709-16, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26334104

RESUMEN

To examine microRNA-133a (miR-133a) endogenous expression in cardiomyocytes after ischemia-reperfusion (I/R) injury and study the effects of miR-133a overexpression on I/R injury-induced cardiomyocyte apoptosis. Dual-Luciferase Reporter Assay detected dynamic expression of miR-133a. In an in vitro hypoxia-reoxygenation (HR) injury model and an in vivo rat model of I/R injury, rat cardiomyocytes were transfected with miR-133a mimic to test the effects of miR-133a overexpression on apoptosis. MiR-133a and Death Associated Protein Kinase 2 (DAPK2) mRNA expression was measured using real-time-PCR, and DAPK2 protein expression was detected by western blotting. Annexin V-fluorescein isothiocyanate/propidium iodide (PI) double-staining measured the apoptosis rate in H9C2 cells and transferase dUTP nick end labeling assay quantified the cardiomyocyte apoptosis rate in tissues obtained from in vivo the rat model. DAPK2 is a target of miR-133a. Both in vitro and in vivo results confirmed that after expression of miR-133a mimics, miR-133a levels increased, which was accompanied by decrease in DAPK2 mRNA and protein expression. In H9C2 cells, HR injury caused a sharp decrease in miR-133a expression and a significant upregualtion of DAPK2 mRNA and protein levels. However, exogenous miR-133a expression led to a significant reduction in DAPK2 mRNA and protein levels despite HR injury. Similar results were obtained from in vivo I/R injury model. After HR injury or I/R injury the apoptosis rate of myocardial cells was highly elevated and decreased significantly only after transfection of miR-133a into cardiomyocytes. MiR-133a overexpression may inhibit I/R injury-mediated cardiomyocyte apoptosis by targeting DAPK2, leading to reduced DAPK2 protein, thus miR-133a may potentially have a high therapeutic value in I/R injury.


Asunto(s)
Proteínas Quinasas Asociadas a Muerte Celular/antagonistas & inhibidores , MicroARNs/genética , MicroARNs/metabolismo , Daño por Reperfusión Miocárdica/prevención & control , Animales , Apoptosis/genética , Línea Celular , Proteínas Quinasas Asociadas a Muerte Celular/genética , Modelos Animales de Enfermedad , Femenino , Marcación de Gen , Modelos Cardiovasculares , Daño por Reperfusión Miocárdica/genética , Daño por Reperfusión Miocárdica/patología , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/patología , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas , Ratas Wistar , Regulación hacia Arriba
20.
Kidney Blood Press Res ; 35(4): 211-9, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22223149

RESUMEN

BACKGROUND: Although C-reactive protein (CRP) is significantly increased in patients with diabetic nephropathy, whether CRP exerts direct proinflammatory effects on human renal tubular epithelial cells (HK-2 cells) is still unclear. METHODS: HK-2 cells were incubated with purified CRP at clinically relevant concentrations (0, 5, 10, 20 and 40 µg/ml). The protein and transcript levels of thrombospondin-1 (TSP-1) and interleukin-6 (IL-6) were determined by ELISA and RT-PCR. Phosphorylation of p38MAPK was investigated through Western blot analysis in HK-2 cells induced by CRP. The activation of nuclear factor-kappa B (NF-κB) was studied via EMSA. A specific p38MAPK inhibitor (SB203580) and an NF-κB inhibitor (PDTC; pyrrolidine dithiocarbamate) were used to analyze the signal transduction in CRP induction. To explore the direct or indirect role of CRP in HK-2 cells, IL-6 or TSP-1 antibodies were used. The expression of IL-6, TSP-1 and transforming growth factor-ß(1 )(TGF-ß(1)) were determined through Western blot analysis in HK-2 cells. RESULTS: In HK-2 cells, purified CRP significantly induced protein release and mRNA expression of IL-6 and TSP-1 in a dose- and time-dependent manner. TGF-ß(1) protein was overexpressed in HK-2 cells induced by CRP, which cannot be inhibited by IL-6 or TSP-1 antibodies. CRP triggered phosphorylation of p38MAPK and activation of NF-κB-mediated signal transduction. SB203580 (5 µM) and PDTC (50 µM) efficiently suppressed those effects of CRP in HK-2 cells. CONCLUSIONS: CRP induces IL-6 and TSP-1 protein release and mRNA expression from HK-2 cells via activation of the p38MAPK and NF-κB signaling pathways and TGF-ß(1) was highly expressed in HK-2 cells, suggesting that CRP plays an important role in the propagation and prolongation of inflammation in renal fibrosis.


Asunto(s)
Proteína C-Reactiva/farmacología , Regulación de la Expresión Génica , Interleucina-6/biosíntesis , FN-kappa B/metabolismo , ARN Mensajero/biosíntesis , Trombospondina 1/biosíntesis , Proteína C-Reactiva/fisiología , Línea Celular , Humanos
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