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1.
Small ; 20(28): e2307900, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38334199

RESUMEN

As a crucial component responsible for the oxygen reduction reaction (ORR), cobalt-rich perovskite-type cathode materials have been extensively investigated in protonic ceramic fuel cell (PCFC). However, their widespread application at a commercial scale is considerably hindered by the high cost and inadequate stability. In response to these weaknesses, the study presents a novel cobalt-free perovskite oxide, Ba0.95La0.05(Fe0.8Zn0.2)0.95O3-δ (BLFZ0.95), with the triple-conducting (H+|O2-|e-) property as an active and robust air electrode for PCFC. The B-site deficiency state contributes significantly to the optimization of crystal and electronic structure, as well as the increase in oxygen vacancy concentration, thus in turn favoring the catalytic capacity. As a result, the as-obtained BLFZ0.95 electrode demonstrates exceptional electrochemical performance at 700 °C, representing extremely low area-specific resistance of 0.04 Ω cm2 in humid air (3 vol.% H2O), extraordinarily high peak power density of 1114 mW cm-2, and improved resistance against CO2 poisoning. Furthermore, the outstanding long-term durability is achieved without visible deterioration in both symmetrical and single cell modes. This study presents a simple but crucial case for rational design of cobalt-free perovskite cathode materials with appreciable performance via B-site deficiency regulation.

2.
Pharmacol Res ; 187: 106636, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36586643

RESUMEN

Idiopathic pulmonary fibrosis (IPF) is a progressive disease with high mortality and limited therapeutic options. The immune checkpoint PD1/PD-L1 axis is related to the pathogenesis of pulmonary fibrosis, and upregulated expression levels of PD-L1 have been demonstrated in IPF patients. However, the mechanism of PD-L1 in pulmonary fibrosis is not fully understood. Here, we demonstrated upregulated expression of PD-L1 in fibrotic lung tissues and sera of IPF patients. Bleomycin (BLM) treatment induced PD-L1 upregulation, EMT (Epithelial-Mesenchymal Transition) and fibrosis-like morphology changes in human pulmonary alveolar epithelial cells (HPAEpiCs). Silencing PD-L1 attenuated BLM-induced EMT and fibrosis-like morphology changes in HPAEpiCs. In addition, we identified that PD-L1 directly binds to vimentin and inhibits vimentin ubiquitination, thereby increasing vimentin levels in HPAEpiCs. Silencing of vimentin inhibited BLM- and PD-L1-induced fibrosis in HPAEpiCs. The correlation between PD-L1 and EMT or vimentin expression was further confirmed in clinical samples and animal models. Finally, we used BLM- and paraquat-induced pulmonary fibrosis animal models to confirm the anti-pulmonary fibrosis effects of PD-L1 silencing. Taken together, our findings suggest that upregulated PD-L1 stimulates EMT of alveolar epithelial cells by increasing vimentin levels by inhibiting vimentin ubiquitination, thereby contributing to pulmonary fibrosis.


Asunto(s)
Antígeno B7-H1 , Fibrosis Pulmonar Idiopática , Animales , Humanos , Regulación hacia Arriba , Vimentina/genética , Vimentina/metabolismo , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Pulmón , Fibrosis Pulmonar Idiopática/inducido químicamente , Fibrosis Pulmonar Idiopática/genética , Fibrosis Pulmonar Idiopática/metabolismo , Transición Epitelial-Mesenquimal , Bleomicina
3.
Molecules ; 28(13)2023 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-37446748

RESUMEN

Liver cancer continues to be a focus of scientific research due to its low five-year survival rate. One of its main core issues is the high metastasis of cells, for which there is no effective treatment. Neferine was originally isolated from Plumula nelumbinis and demonstrated to have a good antitumor effect. In order to extract high-purity Neferine in a more efficient and environmentally friendly manner, response surface methodology (RSM) was used to optimize the isolation and purification procedures in this study. The extract conditions of a 7:3 ratio for the eluent of dichloromethane: methanol, 1:60 for the mass ratio of the extract amount: silica gel, and 3 mL/min of the elution flow rate were shown to be the optimal conditions. These conditions resulted in the highest yield of 6.13 mg per 66.60 mg of starting material, with productivity of 8.76% and purity of 87.04%. Compared with the previous methods, this method can prepare Neferine in large quantities more quickly. We subsequently evaluated the antitumor activity of the purified Neferine against HepG2 hepatic cancer cells. The purified Neferine was found to inhibit the proliferation of HepG2 cells through the CCK-8 assay, with an IC50 of 33.80 µM in 24 h, 29.47 µM in 48 h, 24.35 µM in 72 h and 2.78 µM in 96 h of treatment. Neferine at a concentration of 3 µM could significantly inhibit the migration and invasion abilities of the HepG2 cells in vitro. We also explored the mechanism of action of Neferine via Western blot. We showed that Neferine could reduce RhoA expression by effectively inhibiting the phosphorylation of MYPT1, thereby effectively exerting anti-metastasis activity against HepG2 cells. Thus, we have optimized the isolation procedures for highly pure Neferine by response surface methodology (RSM) in this study, and purified Neferine is shown to play an essential role in the anti-metastasis process of liver cancer cells. The Neferine purification procedure may make a wide contribution to the follow-up development of other anti-metastasis lead compounds.


Asunto(s)
Bencilisoquinolinas , Neoplasias Hepáticas , Humanos , Células Hep G2 , Bencilisoquinolinas/farmacología , Neoplasias Hepáticas/patología , Línea Celular
4.
J Neuroradiol ; 50(2): 209-216, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36041561

RESUMEN

BACKGROUND AND PURPOSE: Currently available methods for determining aneurysm growth are not accurate enough. Therefore, we introduced a more intuitive and accurate 3D registration technology (3DRT) to judge the growth of aneurysms. MATERIALS AND METHODS: We developed an in-house technique for 3DRT and calculated its derivative parameters, voxel change rate (VCR), maximum growth vector (MGV), and parent artery coincidence (PAC). To verify the accuracy, growing aneurysms and stable aneurysms matching 1:3 were selected, and a 3DRT measurement was performed. We calculated the sensitivity, specificity, and accuracy of cases with VCR > 20%, MGV > 1 mm, and combined indicator of VCR > 20% + MGV >1 mm. In addition, we analyzed the cause of the poor registration effect, where the registration effect of PAC > 0.7 was considered acceptable. We also collected 24 consecutive aneurysms for agreement analysis of 2D manual measurement and 3DRT. RESULTS: Twenty-seven growing aneurysms and 81 stable aneurysms were included in the normal model group, and 88 aneurysms with good registration effect in the adjusted model group. For aneurysms with VCR > 20%, the sensitivity and the specificity were the highest at 81.48% and 91.35%, respectively, while in the adjusted model group, the sensitivity and the specificity increased to 94.44% and 94.29%, respectively. When using VCR > 20% as the growth metric, the AUC value in the normal and the adjusted model group was 0.856 and 0.947, respectively. The ICC between 2D manual measurements and the 3DRT was 0.95 (95%CI: 0.88-0.98), and the time spent between the two groups had a significant difference (10.96 min vs. 3.44 min, p<0.01, 95% CI, 6.49-8.53). CONCLUSIONS: A 3DRT can be used to determine the growth of the aneurysm more efficiently, intuitively, and accurately.


Asunto(s)
Aneurisma Roto , Aneurisma Intracraneal , Humanos
5.
Chin J Traumatol ; 26(3): 125-130, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36990837

RESUMEN

The wound mechanism, injury characteristics and treatment principles of anti-armored vehicle ammunition against armored crew in the past 20 years are summarized in this paper. Shock vibration, metal jet, depleted uranium aerosol and post armor breaking effect are the main factors for wounding armored crew. Their prominent characteristics are severe injury, high incidence of bone fracture, high rate of depleted uranium injury, and high incidence of multiple/combined injuries. During the treatment, attention must be paid on that the space of armored vehicle is limited, and the casualties should be moved outside of the cabin for comprehensive treatment. Especially, the management of depleted uranium injury and burn/inhalation injury are more important than other injuries for the armored wounds.


Asunto(s)
Quemaduras , Traumatismo Múltiple , Uranio , Humanos , Uranio/análisis , Aerosoles y Gotitas Respiratorias , Vehículos a Motor , Quemaduras/terapia
6.
Chin J Traumatol ; 26(3): 139-146, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36344366

RESUMEN

PURPOSE: High explosives are used to produce blast waves to study their biological effects. The lungs are considered as the critical target organ in blast-effect studies. The degree of lung hemorrhaging is related to both the explosive power and the increased lung weight. We studied the characteristics of the biological effects from an air explosion of a thermobaric bomb in a high-altitude environment and the lethality and lung injury severity of goats in different orientations and distances. METHODS: Goats were placed at 2.5, 3, 4, and 5 m from the explosion center and exposed them to an air blast at an altitude of 4700-meter. A group of them standing oriented to the right side and the other group seated facing the explosion center vertically. The lung injuries were quantified according to the percentage of surface area contused, and using the pathologic severity scale of lung blast injury (PSSLBI) to score the 4 injury categories (slight, moderate, serious and severe) as 1, 2, 3, and 4, respectively. The lung coefficient (lung weight [g]/body weight [kg]) was the indicator of pulmonary edema and was related to lung injury severity. Blast overpressure data were collected using blast test devices placed at matching locations to represent loadings to goats. All statistical analyses were performed using SPSS, version 26.0, statistical software (SPSS, Inc., Chicago, IL, USA). RESULTS: In total, 127 goats were involved in this study. Right-side-standing goats had a significantly higher mortality rate than those seated vertical-facing (p < 0.05). At the 2.5 m distance, the goat mortality was nearly 100%, whereas at 5 m, all the goats survived. Lung injuries of the right-side-standing goats were 1 - 2 grades more serious than those of seated goats at the same distances, the scores of PSSLBI were significantly higher than the seated vertical-facing goats (p < 0.05). The lung coefficient of the right-side-standing goats were significantly higher than those of seated vertical-facing (p < 0.05). Mortality, PSSLBI, and the lung coefficient results indicated that the right-side-standing goats experienced severer injuries than the seated vertical-facing goats, and the injuries were lessened as the distance increased. The blast overpressure was consistent with these results. CONCLUSION: The main killing factors of the thermobaric bomb in the high-altitude environment were blast overpressure, blast wind propulsions and burn. The orientation and distances of the goats significantly affected the blast injury severity. These results may provide a research basis for diagnosing, treating and protecting against injuries from thermobaric explosions.


Asunto(s)
Traumatismos por Explosión , Lesión Pulmonar , Animales , Lesión Pulmonar/etiología , Cabras , Explosiones , Pulmón/patología
7.
Molecules ; 27(23)2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36500488

RESUMEN

Solid oxide cells (SOCs) have been considered as a promising energy conversion and storage device. However, state-of-the-art cells' practical application with conventionally fabricated Ni-(Y2O3)0.08(ZrO2)0.92 (YSZ) cermet hydrogen electrode and La0.8Sr0.2MnO3 perovskite oxygen electrode is strongly limited by the unsatisfactory performance. Instead, new advances in cell materials and fabrication techniques that can lead to significant performance enhancements are urgently demanded. Here, we report a high-performance reversible SOC that consisted of a combination of SrSc0.175Nb0.025Co0.8O3-δ (SSNC) and phase-inversion tape-casted Ni-YSZ, which served as the oxygen and hydrogen electrode, respectively. The hydrogen electrode synthesized from phase-inversion tape-casting showed a high porosity of 60.8%, providing sufficient active sites for hydrogen oxidation in the solid oxide fuel cell (SOFC) mode and H2O electrolysis in the solid oxide electrolysis cell (SOEC) mode. Accordingly, it was observed that the maximum power density of 2.3 W cm-2 was attained at 750 °C in SOFC mode and a current density of -1.59 A cm-2 was obtained at 1.3 V in SOEC mode. Hence, these results reveal that the simultaneous optimization of oxygen and hydrogen electrodes is a pragmatic strategy that improves the performance of SOCs, which may significantly accelerate the commercialization of such an attractive technology.


Asunto(s)
Niobio , Óxidos , Electrodos , Oxígeno , Hidrógeno
8.
Environ Monit Assess ; 195(1): 55, 2022 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-36326922

RESUMEN

Low-carbon development has always been an important focus of China's economic transformation. In order to promote the development of low-carbon economy, this study used SBM-DEA model to evaluate China's provincial LCEE from 2005 to 2019, studied its temporal and spatial evolution law, used spatial autocorrelation to explore the correlation of China's provincial LCEE, and explored the key influencing factors of LCEE with Tobit model. The empirical results show that the LCEE of most provinces in China is declining, and there are significant differences among different regions in China. Because the eastern region of China can rely on its own human resources, capital environment, and economic foundation, the overall LCEE level is relatively high, while the central and western regions still have obvious deficiencies due to industrial conditions, geographical location, and other factors. LCEE has significant spatial correlation, and neighboring provinces have spillover effects on local LCEE. On this basis, the key factors that affect LCEE are determined. Urbanization level, traffic level, economic development level, financial development, investment in fixed assets, and energy consumption are the important factors that affect LCEE in China, but these influences vary from province to region. It is more reasonable for local governments to develop low-carbon economy according to their own conditions.


Asunto(s)
Carbono , Monitoreo del Ambiente , Humanos , Desarrollo Económico , Urbanización , Industrias , China , Eficiencia
9.
Small ; 17(35): e2101872, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34254432

RESUMEN

Here a new strategy is unveiled to develop superior cathodes for protonic ceramic fuel cells (PCFCs) by the formation of Ruddlesden-Popper (RP)-single perovskite (SP) nanocomposites. Materials with the nominal compositions of LaSrx Co1.5 Fe1.5 O10- δ (LSCFx, x = 2.0, 2.5, 2.6, 2.7, 2.8, and 3.0) are designed specifically. RP-SP nanocomposites (x = 2.5, 2.6, 2.7, and 2.8), SP oxide (x = 2.0), and RP oxide (x = 3.0) are obtained through a facile one-pot synthesis. A synergy is created between RP and SP in the nanocomposites, resulting in more favorable oxygen reduction activity compared to pure RP and SP oxides. More importantly, such synergy effectively enhances the proton conductivity of nanocomposites, consequently significantly improving the cathodic performance of PCFCs. Specifically, the area-specific resistance of LSCF2.7 is only 40% of LSCF2.0 on BaZr0.1 Ce0.7 Y0.2 O3- δ (BZCY172) electrolyte at 600 °C. Additionally, such synergy brings about a reduced thermal expansion coefficient of the nanocomposite, making it better compatible with BZCY172 electrolyte. Therefore, an anode-supported PCFC with LSCF2.7 cathode and BZCY172 electrolyte brings an attractive peak power output of 391 mW cm-2 and excellent durability at 600 °C.

10.
BMC Neurosci ; 22(1): 56, 2021 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-34525970

RESUMEN

BACKGROUND: NRXN1 deletions are identified as one of major rare risk factors for autism spectrum disorder (ASD) and other neurodevelopmental disorders. ASD has 30% co-morbidity with epilepsy, and the latter is associated with excessive neuronal firing. NRXN1 encodes hundreds of presynaptic neuro-adhesion proteins categorized as NRXN1α/ß/γ. Previous studies on cultured cells show that the short NRXN1ß primarily exerts excitation effect, whereas the long NRXN1α which is more commonly deleted in patients involves in both excitation and inhibition. However, patient-derived models are essential for understanding functional consequences of NRXN1α deletions in human neurons. We recently derived induced pluripotent stem cells (iPSCs) from five controls and three ASD patients carrying NRXN1α+/- and showed increased calcium transients in patient neurons. METHODS: In this study we investigated the electrophysiological properties of iPSC-derived cortical neurons in control and ASD patients carrying NRXN1α+/- using patch clamping. Whole genome RNA sequencing was carried out to further understand the potential underlying molecular mechanism. RESULTS: NRXN1α+/- cortical neurons were shown to display larger sodium currents, higher AP amplitude and accelerated depolarization time. RNASeq analyses revealed transcriptomic changes with significant upregulation glutamatergic synapse and ion channels/transporter activity including voltage-gated potassium channels (GRIN1, GRIN3B, SLC17A6, CACNG3, CACNA1A, SHANK1), which are likely to couple with the increased excitability in NRXN1α+/- cortical neurons. CONCLUSIONS: Together with recent evidence of increased calcium transients, our results showed that human NRXN1α+/- isoform deletions altered neuronal excitability and non-synaptic function, and NRXN1α+/- patient iPSCs may be used as an ASD model for therapeutic development with calcium transients and excitability as readouts.


Asunto(s)
Trastorno del Espectro Autista/genética , Proteínas de Unión al Calcio/genética , Redes Reguladoras de Genes/fisiología , Células Madre Pluripotentes Inducidas/fisiología , Moléculas de Adhesión de Célula Nerviosa/genética , Neuronas/fisiología , Adolescente , Trastorno del Espectro Autista/metabolismo , Proteínas de Unión al Calcio/metabolismo , Línea Celular , Células Cultivadas , Niño , Preescolar , Femenino , Humanos , Masculino , Moléculas de Adhesión de Célula Nerviosa/metabolismo , Adulto Joven
11.
Cell Mol Biol (Noisy-le-grand) ; 67(2): 161-165, 2021 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-34817322

RESUMEN

Forkhead box (FOX) transcription factors regulate the development of several human cancers. However, the role and therapeutic potential of FOXA1 in gastric cancer is still largely unexplored. The results showed a significant (P < 0.05) upregulation of FOXA1 in gastric cancer tissues and cell lines. Silencing of FOXA1 in gastric cells significantly (P < 0.05) decreased their viability through induction of apoptosis. The induction of apoptosis was associated with upregulation of Bax and downregulation of Bcl-2. Additionally, FOXA1 silencing caused activation of caspase-3 and 9 with no apparent effects on the expression of caspase-8 suggestive of intrinsic apoptosis. The transwell cell invasion revealed significant (P < 0.05) decline of cell invasion of gastric cancer cells upon FOXA1 silencing. The FOXA1 knockdown further inhibited the in vivo tumor growth suggestive of its therapeutic potential. Taken together, the findings of the present revealed that FOXA1 regulates the proliferation and development of gastric cancer and may exhibit therapeutic implications in gastric cancer treatment.


Asunto(s)
Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Factor Nuclear 3-alfa del Hepatocito/genética , Neoplasias Gástricas/genética , Regulación hacia Arriba , Animales , Apoptosis/genética , Línea Celular Tumoral , Supervivencia Celular/genética , Femenino , Factor Nuclear 3-alfa del Hepatocito/metabolismo , Humanos , Ratones Endogámicos NOD , Ratones SCID , Invasividad Neoplásica , Interferencia de ARN , Tratamiento con ARN de Interferencia/métodos , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patología , Carga Tumoral/genética , Ensayos Antitumor por Modelo de Xenoinjerto/métodos
12.
Ecotoxicol Environ Saf ; 224: 112634, 2021 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-34392153

RESUMEN

Nickel is a heavy metal element extensively distributed in the environment and widely used in modern life. Divalent nickel is one of the most widespread forms of nickel and has been reported as toxic to various tissues. However, whether exposure to divalent nickel negatively affects ovarian homeostasis and oocyte quality remains unclear. In this study, we found that 3 weeks of nickel sulfate exposure affected body growth and decreased the weight and coefficient of the ovary, and increased atretic follicles exhibiting enhanced apoptosis in granulosa cells. Further studies have found that nickel sulfate triggered ovarian fibrosis and inflammation via transforming growth factor-ß1 and nuclear factor-κB pathways, and reduced oocyte development ability. In addition, nickel sulfate increased the level of reactive oxygen species, which induced DNA damage and early apoptosis. Moreover, it was found that nickel sulfate caused damage to the mitochondria showing aberrant morphology, distribution and membrane potential while decreased levels of histone methylation. To summarize, our results indicated that nickel sulfate exposure triggered ovarian fibrosis and inflammation and caused structural and functional disorders of mitochondria in oocytes, which consequently disturbed ovarian homeostasis and follicle development and decreased oocyte quality.

13.
Small ; 16(28): e2001859, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32510184

RESUMEN

Direct ammonia solid oxide fuel cell (DA-SOFC) is superior to low-temperature direct ammonia fuel cell using anion exchange membrane because of much improved anode reaction kinetics at elevated temperature. However, significant performance degradation due to severe sintering of conventional nickel cermet anode under operating conditions is a big challenge for realizing its practical use. Herein, a high-performance anode based on La0.55 Sr0.30 TiO3- δ (LST) perovskite substrate with its surface decorated with in situ exsolved and strongly coupled NiCo alloy nanoparticles (NPs) is designed and fabricated for DA-SOFCs, exhibiting superior catalytic activity for NH3 decomposition reaction due to balanced NH3 adsorption and N2 desorption processes. An electrolyte-supported single cell with infiltrated NiCo/LST on Sm0.2 Ce0.8 O1.9 scaffold anode delivers a maximum power density of 361 mW cm-2 at 800 °C in NH3 fuel, superior to similar SOFCs with Ni or Co NP-decorated LST based anodes (161 and 98 mW cm-2 ). Furthermore, the SOFC with this newly developed anode displays favorable operational stability without obvious performance degradation at 700 °C for a test period of ≈120 h, attributed to its high antisintering capability. This study provides some strategies to develop highly active, stable, and antisintering perovskite-based nanocomposite for DA-SOFCs, facilitating the practical use of this technology.

14.
Bioorg Med Chem Lett ; 30(8): 127073, 2020 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-32139326

RESUMEN

A new water-soluble 4-amino-1, 8-naphthalimide based fluorescent sensor, with iminoacetic acid and iminoethoxyacetic acid as receptor contained two different arms, was developed. Under physiological pH conditions, it demonstrates good water solubility, high selectivity and sensitivity for sensing Zn2+ with about 20-fold enhancement in aqueous solution, with a characteristic emission band of 4-amino-1, 8-naphthalimide with a green color centered at 550 nm. It was applied successfully to detect Zn2+ in living cells.


Asunto(s)
Descubrimiento de Drogas , Colorantes Fluorescentes/química , Zinc/análisis , Teoría Funcional de la Densidad , Relación Dosis-Respuesta a Droga , Colorantes Fluorescentes/síntesis química , Células HeLa , Humanos , Estructura Molecular , Imagen Óptica , Solubilidad , Espectrometría de Fluorescencia , Relación Estructura-Actividad , Agua/química
15.
Mol Carcinog ; 58(1): 55-65, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30182377

RESUMEN

Liver cancer stem cells (CSCs) were involved in tumorigenesis, progression, recurrence, and drug resistance of hepatocellular carcinoma (HCC). miR-365 was downregulated in hepatocellular carcinoma and inhibited HCC cell proliferation and invasion. However, the role of miR-365 in liver cancer stem cells was unknown. Herein, we observed a remarkable decrease of miR-365 expression in CD133 or EpCAM-positive liver CSCs as well as in CSC-enriched hepatoma spheres. Up-regulated miR-365 suppressed liver CSC expansion by inhibiting the dedifferentiation of hepatoma cells and decreasing the self-renewal ability of liver CSCs. Mechanistically, bioinformatic and luciferase reporter analysis identified Ras-related C3 botulinum toxin substrate 1 (RAC1) as a direct target of miR-365. Overexpression of miR-365 in hepatoma cells downregulated the RAC1 mRNA and protein expression. RAC1 also could promote the expansion of liver CSCs. The special RAC1 inhibitor EHop-106 or RAC1 overexpression abolished the discrepancy in liver CSC proportion and the self-renewal capacity between miR-365 overexpression hepatoma cells and control cells, which further confirmed that RAC1 was required in miR-365-suppressed liver CSCs expansion. miR-365 was downregulated in liver CSCs and could inhibit HCC cells dedifferentiation and liver CSCs expansion by targeting RAC1 signaling.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Carcinoma Hepatocelular/patología , Regulación Neoplásica de la Expresión Génica , Neoplasias Hepáticas/patología , MicroARNs/genética , Células Madre Neoplásicas/patología , Proteína de Unión al GTP rac1/metabolismo , Apoptosis , Biomarcadores de Tumor/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Proliferación Celular , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Células Madre Neoplásicas/metabolismo , Pronóstico , Células Tumorales Cultivadas , Proteína de Unión al GTP rac1/genética
16.
Bioorg Med Chem Lett ; 29(18): 2646-2649, 2019 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-31362923

RESUMEN

A new 4-amino-1,8-naphthalimide-based fluorescent sensor, with iminoacetic acid and iminoethoxyacetic acid as receptor, was developed. It was applied successfully to detect Zn2+ in aqueous solution and living cells. Under physiological pH conditions, it demonstrates high selectivity and sensitivity for sensing Zn2+ with about 7-fold enhancement in aqueous solution, with a characteristic emission band of 4-amino-1,8-naphthalimide with a green color centered at 550 nm.


Asunto(s)
Colorantes Fluorescentes/química , Naftalimidas/química , Zinc/análisis , Colorantes Fluorescentes/síntesis química , Células HeLa , Humanos , Concentración de Iones de Hidrógeno , Estructura Molecular , Naftalimidas/síntesis química , Imagen Óptica , Espectrometría de Fluorescencia
17.
Int J Mol Sci ; 20(4)2019 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-30823542

RESUMEN

Due to their beneficial effects on human health, antioxidant peptides have attracted much attention from researchers. However, the structure-activity relationships of antioxidant peptides have not been fully understood. In this paper, quantitative structure-activity relationships (QSAR) models were built on two datasets, i.e., the ferric thiocyanate (FTC) dataset and ferric-reducing antioxidant power (FRAP) dataset, containing 214 and 172 unique antioxidant tripeptides, respectively. Sixteen amino acid descriptors were used and model population analysis (MPA) was then applied to improve the QSAR models for better prediction performance. The results showed that, by applying MPA, the cross-validated coefficient of determination (Q²) was increased from 0.6170 to 0.7471 for the FTC dataset and from 0.4878 to 0.6088 for the FRAP dataset, respectively. These findings indicate that the integration of different amino acid descriptors provide additional information for model building and MPA can efficiently extract the information for better prediction performance.


Asunto(s)
Antioxidantes/química , Oligopéptidos/química , Relación Estructura-Actividad Cuantitativa , Aminoácidos/química , Antioxidantes/farmacología , Conjuntos de Datos como Asunto , Humanos , Modelos Químicos , Oligopéptidos/farmacología
18.
Zhongguo Zhong Yao Za Zhi ; 44(18): 3924-3934, 2019 Sep.
Artículo en Zh | MEDLINE | ID: mdl-31872726

RESUMEN

Lotus( Nelumbo nucifera) is a traditional medicinal plant,and nowadays it is regarded both as medicine and food. It is widespread across China and rich in natural resources. Almost every part of N. nucifera could be used for medical or edible purpose,including seeds( Lianzi),black ripe fruits( Shilianzi),seed coats( Lianyi),green embryos of mature seed( Lianzixin),flowers( Lianhua),stamens( Lianxu),receptacles( Lianfang),leaves( Heye),leaf or flower stalks( Hegeng),leaf bases( Heyedi),rhizomes( Ou) and rhizome nodes( Oujie). Therefore,this plant is praised as a commercial crop with great economic values. Isoquinoline type alkaloids are the main chemical components of lotus. Smooth muscles usually exist in the digestive tract,respiratory tract and vascular,urinary,reproductive and other human systems. Dysfunction of smooth muscle contraction will induce many diseases including hypertension,asthma and gastrointestinal disorder,etc.,and most of current therapeutic strategies rely on relaxation of smooth muscle by drugs.Previous studies have shown that alkaloids of lotus have strong relaxation activity on smooth muscle. The present paper reviews phytochemistry and smooth muscle relaxation activity of 59 isoquinoline alkaloids from N. nucifera through accessing CNKI,PubMed and multiple databases for biomedical sciences.


Asunto(s)
Alcaloides/farmacología , Isoquinolinas/farmacología , Relajación Muscular , Músculo Liso/efectos de los fármacos , Nelumbo/química , China , Humanos , Fitoquímicos/farmacología , Extractos Vegetales
19.
Am J Physiol Regul Integr Comp Physiol ; 314(1): R1-R11, 2018 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-28978514

RESUMEN

Our previous study demonstrated that connexin (Cx)43 participated in the regulation of vascular permeability in severe sepsis. Osteopontin (OPN) has been demonstrated to participate in the occurrence of atherosclerosis, inflammation, as well as the adhesion and migration of cells. It is not clear whether OPN is involved in Cx43 regulating vascular permeability after sepsis and if it is related to tight-junction proteins. with the use of cecal ligation and puncture (CLP)-induced septic rats and lipopolysaccharide (LPS)-treated pulmonary vein vascular endothelial cells (VECs), the role of zona occuldens 1 (ZO-1) and claudin-5 in Cx43 regulation of vascular permeability and its relationship to OPN were investigated in the present study. The results showed that the expression of ZO-1 and claudin-5 in pulmonary vein were decreased in CLP rats and LPS-treated pulmonary vein VECs. Cx43-overexpressed lentivirus induced the degradation of ZO-1 and claudin-5, while Cx43 RNAi lentivirus abrogated the degradation of ZO-1 and claudin-5 induced by LPS. The vascular permeability and expression of OPN in pulmonary veins were significantly increased in CLP rats and LPS-treated pulmonary vein VECs. Silencing OPN by OPN RNAi lentivirus inhibited the vascular hyperpermeability induced by LPS. Overexpressed Cx43 lentivirus increased the expression of OPN and vascular permeability and downregulated the expression of ZO-1 and claudin-5 in pulmonary vein VECs. Silencing OPN by OPN RNAi lentivirus inhibited the effects of Cx43-overexpressed lentivirus on downregulation of ZO-1 and claudin-5 and vascular hyperpermeability in pulmonary vein VECs. Transfection of specific double-stranded RNA targeting to ß-catenin and T-cell factor-4 (Tcf-4) abolished the upregulation of OPN induced by Cx43 overexpression. These results suggest that OPN participates in the regulation of vascular permeability by Cx43 after sepsis. Cx43 upregulation of OPN is via the Tcf-4/ß-catenin transcription pathway; OPN increases vascular permeability by downregulating the expression of the tight junction proteins ZO-1 and claudin-5.


Asunto(s)
Permeabilidad Capilar , Conexina 43/metabolismo , Células Endoteliales/metabolismo , Pulmón/irrigación sanguínea , Osteopontina/metabolismo , Venas Pulmonares/metabolismo , Sepsis/metabolismo , Uniones Estrechas/metabolismo , Animales , Células Cultivadas , Claudina-5/genética , Claudina-5/metabolismo , Conexina 43/genética , Modelos Animales de Enfermedad , Células Endoteliales/microbiología , Femenino , Masculino , Osteopontina/genética , Venas Pulmonares/microbiología , Venas Pulmonares/fisiopatología , Ratas Sprague-Dawley , Sepsis/microbiología , Sepsis/fisiopatología , Transducción de Señal , Uniones Estrechas/microbiología , Factores de Tiempo , Factor de Transcripción 4/genética , Factor de Transcripción 4/metabolismo , Proteína de la Zonula Occludens-1/genética , Proteína de la Zonula Occludens-1/metabolismo , beta Catenina/genética , beta Catenina/metabolismo
20.
Chemistry ; 24(52): 13800-13806, 2018 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-29981182

RESUMEN

Water electrolysis is regarded as a green and highly efficient approach to producing high-purity hydrogen, but commercialization of this technology still requires the development of high-performance and affordable electrocatalysts for the hydrogen evolution reaction (HER). Currently, because of its excellent electrical conductivity and good corrosion resistance in acidic media, cobalt phosphide (CoP) has become a representative non-noble-metal HER catalyst despite its inadequate catalytic activity. Herein, a strategy of multiple catalyst-structure engineering, which simultaneously includes doping, nanostructuring, and in situ nanocarbon coating, was employed to significantly improve the HER performance of CoP. CoP with optimized ruthenium doping and covered by ultrathin graphitic carbon shells shows remarkably high HER catalytic behaviour with a low overpotential of only 73 mV at a current density of 10 mA cm-2 and a small Tafel slope of 46 mV dec-1 , close to that of the Pt/C benchmark, while maintaining excellent durability. Moreover, the ultrathin graphene shell has a significant positive effect on catalytic activity. This work demonstrates the necessity and validity of multifold structural control, which can be widely used to design various materials for different catalytic processes.

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