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1.
Adv Mater ; : e2408213, 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39054683

RESUMEN

Zinc dendrite, active iodine dissolution, and polyiodide shuttle caused by the strong interaction between liquid electrolyte and solid electrode are the chief culprits for the capacity attenuation of aqueous zinc-iodine batteries (ZIBs). Herein, mullite is adopted as raw material to prepare Zn-based solid-state electrolyte (Zn-ML) for ZIBs through zinc ion exchange strategy. Owing to the merits of low electronic conductivity, low zinc diffusion energy barrier, and strong polyiodide adsorption capability, Zn-ML electrolyte can effectively isolate the redox reactions of zinc anode and AC@I2 cathode, guide the reversible zinc deposition behavior, and inhibit the active iodine dissolution as well as polyiodide shuttle during cycling process. As expected, wide operating voltage window of 2.7 V (vs Zn2+/Zn), high Zn2+ transference number of 0.51, and low activation energy barrier of 29.7 kJ mol-1 can be achieved for the solid-state Zn//Zn cells. Meanwhile, high reversible capacity of 127.4 and 107.6 mAh g-1 can be maintained at 0.5 and 1 A g-1 after 3 000 and 2 100 cycles for the solid-state Zn//AC@I2 batteries, corresponding to high-capacity retention ratio of 85.2% and 80.7%, respectively. This study will inspire the development of mineral-derived solid electrolyte, and facilitate its application in Zn-based secondary batteries.

2.
Am J Physiol Endocrinol Metab ; 326(5): E723-E734, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38506753

RESUMEN

Type 1 diabetes (T1D) is an autoimmune disease characterized by the destruction of beta cells by immune cells. The interactions among cells within the islets may be closely linked to the pathogenesis of T1D. In this study, we used single-cell RNA sequencing (scRNA-Seq) to analyze the cellular heterogeneity within the islets of a T1D mouse model. We established a T1D mouse model induced by streptozotocin and identified cell subpopulations using scRNA-Seq technology. Our results revealed 11 major cell types in the pancreatic islets of T1D mice, with heterogeneity observed in the alpha and beta cell subgroups, which may play a crucial role in the progression of T1D. Flow cytometry further confirmed a mature alpha and beta cell reduction in T1D mice. Overall, our scRNA-Seq analysis provided insights into the cellular heterogeneity of T1D islet tissue and highlighted the potential importance of alpha and beta cells in developing T1D.NEW & NOTEWORTHY In this study, we created a comprehensive single-cell atlas of pancreatic islets in a T1D mouse model using scRNA-Seq and identified 11 major cell types in the islets, highlighting the role of alpha and beta cells in T1D. This study revealed a significant reduction in the maturity alpha and beta cells in T1D mice through flow cytometry. It also demonstrated the heterogeneity of alpha and beta cells, potentially crucial for T1D progression. Overall, our scRNA-Seq analysis provided new insights for understanding and treating T1D by studying cell subtype changes and functions.


Asunto(s)
Diabetes Mellitus Tipo 1 , Células Secretoras de Insulina , Islotes Pancreáticos , Análisis de Secuencia de ARN , Análisis de la Célula Individual , Animales , Ratones , Diabetes Mellitus Tipo 1/genética , Análisis de la Célula Individual/métodos , Islotes Pancreáticos/metabolismo , Islotes Pancreáticos/citología , Células Secretoras de Insulina/metabolismo , Análisis de Secuencia de ARN/métodos , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/patología , Células Secretoras de Glucagón/metabolismo , Femenino , RNA-Seq/métodos , Ratones Endogámicos C57BL
3.
ACS Nano ; 17(18): 18128-18138, 2023 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-37690054

RESUMEN

Multimetallic alloys have demonstrated promising performance for the application of metal-air batteries, while it remains a challenge to design multimetallic single-atom catalysts (MM-SACs). Herein, metal-C3N4 and nitrogen-doped carbon are employed as cornerstones to synthesize MM-SACs by a general two-step method, and the inherent features of atomic dispersion and the strong electronic reciprocity between the multimetallic sites have been verified. The trimetallic FeCoZn-SACs and quatermetallic FeCoCuZn-SACs are both found to deliver superior oxygen evolution reaction and oxygen reduction reaction activity, respectively, as well as outstanding bifunctional durability. Density functional theory calculations elucidate the crucial contribution of Co sites of FeCoCuZn-SACs to the efficient catalysis of both the ORR and the OER. More importantly, Zn-air batteries with FeCoCuZn-SACs as cathodic catalysts exhibit a high power density (252 mW cm-2), high specific capacity (817 mAh gZn-1), and considerable stability (over 225 h) for charging-discharging processes. This work provides a visual perspective for the advantages of MM-SACs toward oxygen electrocatalysis.

4.
J Colloid Interface Sci ; 650(Pt B): 1466-1475, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37481784

RESUMEN

It is worthwhile to explore and develop multifunctional composites with unique advantages for energy conversion and utilization. Post-synthetic modification (PSM) strategies can endow novel properties to already excellent covalent organic frameworks (COFs). In this study, we prepared a range of COF-based composites via a multi-step PSM strategy. COF-Ph-OH was acquired by demethylation between anhydrous BBr3 and - OMe, and then, M@COF-Ph-OH was further obtained by forming the N - M - O structure. COF-Ph-OH exhibited a 2e--dominated oxygen reduction reaction (ORR) pathway with high H2O2 selectivity, while M@COF-Ph-OH exhibited a 4e--dominated ORR pathway with low H2O2 selectivity, which was due to the introduction of a metal salt with a d electron structure that facilitated the acquisition of electrons and changed the adsorption energy of the reaction intermediate (*OOH). It was proven that the d electron structure was effective at regulating the reaction pathway of the electrocatalytic ORR. Moreover, Co@COF-Ph-OH showed better 4e- ORR properties than Fe@COF-Ph-OH and Ni@COF-Ph-OH. In addition, compared with the other sulfur-impregnated COF-based composites examined in this study, S-Co@COF-Ph-OH had a larger initial capacity, a weaker impedance, and a stronger cycling durability in Li-S batteries, which was attributed to the unique porous structure ensuring high sulfur utilization, the loaded cobalt accelerating LiPS electrostatic adsorption and promoting LiPS catalytic conversion, and the benzoquinoline ring structure being ultra-stable. This work offers not only a rational and feasible strategy for the synthesis of multifunctional COF-based composites, but also promotes their application in electrochemistry.

5.
Dalton Trans ; 52(9): 2684-2692, 2023 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-36745451

RESUMEN

The development of efficient non-precious metal oxygen reduction reaction catalysts to replace Pt-based catalysts is of great significance to accelerate the commercial application of fuel cells. In this study, a hierarchical porous carbon oxygen reduction reaction catalyst with Fe/Fe5C2/Fe1-xS@Fe-N-C active sites was developed via a simple and efficient solid-phase synthesis method. The introduction of zinc inhibited the growth and agglomeration of the nanoparticles and induced the formation of active nitrogen species and porosity, thus boosting the catalytic activity. The optimal FeZn-N-C-1 catalyst exhibited a high half-wave potential of 0.846 V, which is 24 mV higher than that of the commercial Pt/C, with a 4-e- reaction path under alkaline conditions. When the FeZn-N-C-1 catalyst is employed as a cathode in a zinc-air battery, it achieves a high open circuit voltage of 1.54 V, power density of 143.6 mW cm-2 and specific capacity of 804 mA h g-1.

6.
Nat Commun ; 13(1): 5071, 2022 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-36038594

RESUMEN

The controllable anchoring of multiple isolated metal atoms into a single support exhibits scientific and technological opportunities, while the synthesis of catalysts with multiple single metal atoms remains a challenge and has been rarely reported. Herein, we present a general route for anchoring up to eleven metals as highly dispersed single-atom centers on porous nitride-doped carbon supports with the developed movable type printing method, and label them as high-entropy single-atom catalysts. Various high-entropy single-atom catalysts with tunable multicomponent are successfully synthesized with the same method by adjusting only the printing templates and carbonization parameters. To prove utility, quinary high-entropy single-atom catalysts (FeCoNiCuMn) is investigated as oxygen reduction reaction catalyst with much more positive activity and durability than commercial Pt/C catalyst. This work broadens the family of single-atom catalysts and opens a way to investigate highly efficient single-atom catalysts with multiple compositions.

7.
ACS Appl Mater Interfaces ; 14(11): 13369-13378, 2022 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-35266383

RESUMEN

Microbial fuel cells (MFCs) can be capable of both wastewater treatment and electricity generation, which necessarily depends on the increasing cathodic performances and stability at low cost to realize industrialization. Herein, cellulose, a commercially available and sustainable material, was oxidized as a carbon precursor to produce the oxygen species synergizing the nitrogen-doped carbon (CON-900) catalyst by a facile in situ nitrogen doping method. The incorporation of nitrogen and oxygen with a high content creates more active centers. Meanwhile, the hierarchical porosity of CON-900 contributes to a high specific surface area (652 m2 g-1) and the exposure of accessible active sites. As expected, CON-900 exhibits considerable activity for the oxygen reduction reaction, excellent operating stability, and high poisoning resistance. In addition, the MFC fabricated with CON-900 as a cathode catalyst demonstrates a maximum power density of 1014 ± 23 mW m-2, which is comparable with that of the Pt/C cathode (1062 ± 14 mW m-2). This work offers a facile and versatile strategy for various biomass materials to develop low-cost and high-efficiency carbon-based catalysts for MFCs and beyond.


Asunto(s)
Fuentes de Energía Bioeléctrica , Carbono/química , Catálisis , Celulosa , Electrodos , Nitrógeno/química , Oxígeno/química
8.
J Colloid Interface Sci ; 607(Pt 2): 1091-1102, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34571296

RESUMEN

Hydrogen energy is expected to replace fossil fuels as a mainstream energy source in the future. Currently, hydrogen production via water electrolysis yields high hydrogen purity with easy operation and without producing polluting side products. Presently, platinum group metals and their oxides are the most effective catalysts for water splitting; however, their low abundance and high cost hinder large-scale hydrogen production, especially in alkaline and neutral media. Therefore, the development of high-efficiency, durable, and low-cost electrocatalysts is crucial to improving the overpotential and lowering the electrical energy consumption. As a solution, Ni2P has attracted particular attention, owing to its desirable electrical conductivity, high corrosion resistance, and remarkable catalytic activity for overall water splitting, and thus, is a promising substitute for platinum-group catalysts. However, the catalytic performance and durability of raw Ni2P are still inferior to those of noble metal-based catalysts. Heteroatom doping is a universal strategy for enhancing the performance of Ni2P for water electrolysis over a wide pH range, because the electronic structure and crystal structure of the catalyst can be modulated, and the adsorption energy of the reaction intermediates can be adjusted via doping, thus optimizing the reaction performance. In this review, first, the reaction mechanisms of water electrolysis, including the cathodic hydrogen evolution reaction and anodic oxygen evolution reaction, are briefly introduced. Then, progress into heteroatom-doped nickel phosphide research in recent years is assessed, and a discussion of each representative work is given. Finally, the opportunities and challenges for developing advanced Ni2P based electrocatalysts are proposed and discussed.

9.
ACS Appl Mater Interfaces ; 13(44): 52681-52687, 2021 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-34705413

RESUMEN

Exploring effective, stable, and affordable oxygen reduction reaction (ORR) catalysts is very significant for the practical application of proton-exchange membrane fuel cells. In this work, a facile and expandable method is developed to prepare ultrathin PtNi nanowires (NWs) with various Pt/Ni contents, and the ORR performance of the synthesized samples is thoroughly investigated. Pt3.2Ni NWs show the best ORR performance among the studied samples and, notably, exhibit much better ORR activity and stability than those of the Pt/C catalyst even after a 300,000-continuous cycling test. This work confirms that the initial Pt/Ni ratio plays a critical role in the ORR activity and stability of PtNi NWs, and the structure of the PtNi NWs can be well retained after the durability test. Additionally, the structure and performance of Pt3.2Ni NWs are investigated in detail during various cycles, and the performance decay is attributed to the dealloying of Ni and the corrosion of the one-dimensional structure after a prolonged durability test. This work provides a desirable method for rationally synthesizing a highly efficient ORR electrocatalyst with remarkable stability.

10.
Ann Transl Med ; 9(6): 503, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33850900

RESUMEN

BACKGROUND: Ultraviolet B (UVB) has been reported to prevent bone loss by promoting the synthesis of vitamin D. However, UVB can also enhance osteoclastic differentiation, inhibit osteogenic differentiation, and cause oxidative damage. The present study aimed to analyze the osteoprotective effects of UVB and conjugated linoleic acid (CLA) in rats with ovariectomy-induced osteoporosis, and to determine the interactions between UVB and CLA and their effects on bone mesenchymal stem cells (BMSCs) and bone marrow mononuclear cells (BMMCs). METHODS: In vitro, the distance of UVB irradiation and the dose of CLA were selected by immunofluorescence assays and Cytotoxicity assay. BMSCs and BMMCs were detected by immunohistochemical and immunofluorescence assays. In vivo, three-month-old female Sprague-Dawley rats that had undergone ovariectomy were treated with UVB and CLA. After 8 weeks of therapy, the femurs of the rats were examined by micro-computed tomography (CT) and immunohistochemical detection to assess the therapeutic efficacy. RESULTS: The least inhibitive UVB distance and dosage of CLA were selected for the in vivo experiments. CLA effectively weakened the osteogenic inhibitory effect of UVB (72 cm), significantly improved the activity of alkaline phosphatase (ALP), promoted the formation of mineralized nodules, and alleviated the oxidative damage induced by UVB. CLA also effectively weakened the osteoclast-promoting effect of UVB (72 cm), inhibited osteoclast formation, and inhibited the inflammatory damage to BMMCs caused by UVB (72 cm) irradiation. Micro-CT results showed that UVB irradiation could promote bone formation in ovariectomized Sprague-Dawley rats, while CLA could significantly promote bone regeneration. Immunofluorescence assays results showed that CLA alleviated UVB-induced oxidative damage to osteoblasts. The ROS detection results demonstrated that CLA effectively alleviated UVB-induced oxidative damage to BMSCs. Furthermore, Immunohistochemical assays showed that UVB and CLA treatment increased bone density, inhibited osteolytic osteolysis, and enhanced osteogenic activity. CONCLUSIONS: CLA can effectively weaken osteoclast promotion, osteogenic inhibition, and oxidative damage caused by UVB. Combination treatment of UVB and CLA exerts an osteoprotective effect on ovariectomized osteoporotic rats and stimulates osteogenesis. The molecular mechanism of this interaction requires further investigation.

11.
J Int Med Res ; 49(3): 300060521993980, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33787392

RESUMEN

OBJECTIVES: Liver echinococcosis is a severe zoonotic disease caused by Echinococcus (tapeworm) infection, which is epidemic in the Qinghai region of China. Here, we aimed to explore biomarkers and establish a predictive model for the diagnosis of liver echinococcosis. METHODS: Microarray profiling followed by Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analysis was performed in liver tissue from patients with liver hydatid disease and from healthy controls from the Qinghai region of China. A protein-protein interaction (PPI) network and random forest model were established to identify potential biomarkers and predict the occurrence of liver echinococcosis, respectively. RESULTS: Microarray profiling identified 1152 differentially expressed genes (DEGs), including 936 upregulated genes and 216 downregulated genes. Several previously unreported biological processes and signaling pathways were identified. The FCGR2B and CTLA4 proteins were identified by the PPI networks and random forest model. The random forest model based on FCGR2B and CTLA4 reliably predicted the occurrence of liver hydatid disease, with an area under the receiver operator characteristic curve of 0.921. CONCLUSION: Our findings give new insight into gene expression in patients with liver echinococcosis from the Qinghai region of China, improving our understanding of hepatic hydatid disease.


Asunto(s)
Biología Computacional , Equinococosis , Biomarcadores , China/epidemiología , Equinococosis/diagnóstico , Equinococosis/genética , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Ontología de Genes , Redes Reguladoras de Genes , Humanos , Hígado , Aprendizaje Automático
12.
J Orthop Surg Res ; 16(1): 133, 2021 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-33579305

RESUMEN

BACKGROUND: Osteoarthritis (OA) is thought to be the most prevalent chronic joint disease, especially in Tibet of China. Here, we aimed to explore the integrative lncRNA and mRNA landscape between the OA patients of Tibet and Han. METHODS: The lncRNA and mRNA expression microarray profiling was performed by SurePrint G3 Human Gene Expression 8x60K v2 Microarray in articular cartilage samples from OA patients of Han nationality and Tibetans, followed by GO, KEGG, and trans-regulation and cis-regulation analysis of lncRNA and mRNA. RESULTS: We found a total of 117 lncRNAs and 297 mRNAs differently expressed in the cartilage tissues of Tibetans (n = 5) comparing with those of Chinese Han (n = 3), in which 49 lncRNAs and 158 mRNAs were upregulated, and 68 lncRNAs and 139 mRNAs were downregulated. GO and KEGG analysis showed that several unreported biological processes and signaling pathways were particularly identified. LncRNA-mRNA co-expression analysis revealed a remarkable lncRNA-mRNA relationship, in which OTOA may play a critical role in the different mechanisms of the OA progression between Tibetans and Chinese Han. CONCLUSION: This study identified different lncRNA/mRNA expression profiling between OA patients of Tibetans and Han, which were involved in many characteristic biological processes and signaling pathways.


Asunto(s)
Perfilación de la Expresión Génica/métodos , Expresión Génica/genética , Genética de Población , Osteoartritis/genética , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Análisis de Matrices Tisulares/métodos , Pueblo Asiatico/genética , Cartílago Articular/metabolismo , China , Humanos , Tibet
13.
Aging (Albany NY) ; 13(1): 1440-1457, 2021 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-33406504

RESUMEN

Septic shock is one of the most significant health concerns across the world, involving hypo-perfusion and defects in tissue energy. The current study investigates the role of NLR family CARD domain containing protein 4 (NLRC4) in septic shock-induced inflammatory reactions, lung tissue injuries, and dendritic cell (DC) apoptosis. Septic shock mice models were established by modified cecal ligation and puncture and injected with retroviral vector expressing siRNA-NLRC4. DCs were then isolated and transfected with siRNA-NLRC4. The degree of lung tissue injury, cell cycle distribution, cell apoptosis and cell viability of DCs were assessed. NLRC4 was found to be expressed at high levels in mice with septic shock. NLRC4 silencing inhibited the activation of the NOD-like receptor (NLR) pathway as evidenced by the decreased levels of NOD1, NOD2, RIP2, and NF-κB. In addition, NLRC4 silencing reduced the inflammatory reaction as attributed by reduced levels of IL-1ß, TNF-α and IL-6. Suppressed NLRC4 levels inhibited cell viability and promoted cell apoptosis evidenced by inhibited induction of DC surface markers (CD80, CD86, and MHC II), along with alleviated lung tissue injury. In conclusion, NLRC4 silencing ameliorates lung injury and inflammation induced by septic shock by negatively regulating the NLR pathway.


Asunto(s)
Proteínas Reguladoras de la Apoptosis/metabolismo , Proteínas de Unión al Calcio/metabolismo , Células Dendríticas/patología , Inflamación/metabolismo , Choque Séptico/metabolismo , Animales , Apoptosis/fisiología , Proliferación Celular/fisiología , Técnicas de Silenciamiento del Gen , Inflamación/patología , Lesión Pulmonar/metabolismo , Lesión Pulmonar/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Proteínas NLR/metabolismo , Choque Séptico/patología
14.
Life Sci ; 270: 119012, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33422543

RESUMEN

AIMS: Memantine is a non-competitive antagonist of glutamatergic NMDA receptor that is mainly used in the treatment of Alzheimer's disease. The excitatory toxicity mediated by glutamate via glutamatergic receptor signals is considered to be one of the mechanisms mediating neuronal injury and cognitive impairment after exposure to a hypoxic environment at a high altitude. Therefore, in this study, we hypothesized that inhibiting glutamate signaling using memantine could alleviate neuronal injury and cognitive impairment in rats exposed to chronic hypoxia. MAIN METHODS: we made animal models in the natural environment of the Qinghai-Tibet Plateau at an altitude of 4300 m, and used animal behavior, morphology, molecular biology and other methods to evaluate the impact of chronic hypoxia exposure on cognitive function and the neuroprotective effect of Memantine. KEY FINDINGS: Our results showed that the expression of NMDA receptors increased, while the expression of AMPA receptors decreased, after 4 weeks of chronic hypoxia exposure. Concomitantly, apoptotic neuronal cell death in the hippocampus and frontal cortex was significantly increased, along with levels of oxidative stress, whereas innate ability to inhibit free radicals decreased. Moreover, after 8 weeks of hypoxia exposure, learning, memory, and space exploration abilities were significantly decreased. Notably, after treatment with memantine, apoptotic neuronal cell death, oxidative stress, and free radical levels decreased, and the cognitive function of the animals improved. SIGNIFICANCE: Present study shows that chronic hypoxia can produce the excitatory toxicity leading to neural injury and cognitive impairment that can be suppressed with memantine treatment by inhibiting excitatory toxicity.


Asunto(s)
Mal de Altura/metabolismo , Disfunción Cognitiva/tratamiento farmacológico , Memantina/farmacología , Altitud , Mal de Altura/tratamiento farmacológico , Enfermedad de Alzheimer/tratamiento farmacológico , Animales , Muerte Celular/efectos de los fármacos , Cognición/efectos de los fármacos , Modelos Animales de Enfermedad , Antagonistas de Aminoácidos Excitadores/farmacología , Ácido Glutámico/metabolismo , Hipocampo/metabolismo , Hipoxia/metabolismo , Masculino , Memantina/metabolismo , Memoria/efectos de los fármacos , Neuronas/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Neurotoxinas/metabolismo , Estrés Oxidativo/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Receptores de N-Metil-D-Aspartato/metabolismo
15.
RSC Adv ; 11(18): 10688-10698, 2021 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-35423547

RESUMEN

The polymers based on thiophene armed triazine and different thiophene derivatives including thiophene (Th), thieno[3,2-b]thiophene (TT), dithieno[3,2-b:2',3'-d]thiophene (DTT) or thieno[2',3':4,5]thieno[3,2-b]thieno[2,3-d]thiophene (TTTT) are synthesized through a Stille coupling reaction. By introducing thiophene derivatives with increasing sizes as the linkage units (from thiophene, DT to DTT, TTTT), the band gaps (E g) of the resultant polymers decrease continuously. Then the composite materials (polymer@C) between polymers and Vulcan XC-72 carbon are prepared by in situ polymerization to test their electrochemical performances in lithium ion batteries. The synthesized composites show distinct morphologies due to the different linkage units of thiophene or fused cyclothiophene derivatives and the cross-linked structure can be found in composites with the longer thiophene derivatives (bridging molecules) like PTT-3@C and PTT-4@C, which are expected to be beneficial to improve the performances of the electrode materials. The specific capacities of the composites are 495 mA h g-1, 671 mA h g-1, 707 mA h g-1, and 772 mA h g-1 for PTT-1@C, PTT-2@C, PTT-3@C and PTT-4@C at a current density of 100 mA g-1, respectively. In particular, benefiting from the enlarged conjugation length and planarity of the linkage units, the conjugated microporous polymers could deliver continuously improved capacities.

16.
Am J Transl Res ; 12(8): 4550-4560, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32913528

RESUMEN

To evaluate the effect of dance on vascular-related factors and cerebral hemodynamics in elderly individuals in Qinghai-Tibetan plateau regions (mean altitude ≥2,300 m). Thirty elderly individuals, who practiced traditional Tibetan Guozhuang dance or did not, were enrolled, respectively. Serum PGC-1α, HCY, FSTL-1, VEGF and HIF-1α were measured by ELISA assays. Carotid artery stenosis and plaque, IMT, extracranial internal carotid artery stenosis and cerebral arteriosclerosis were evaluated using CUS and TCD. Body weight, BMI, heart rate, systolic pressure, and diastolic pressure, serum BGS, TC, LDL, HIF-1α, VEGF, and HCY in the dance group were significantly lower than the no-dance group. FSTL-1 levels, SO2 and SO2/heart rate ratio in the dance group were significantly higher than the no-dance group. Incidence of extracranial internal carotid artery stenosis, carotid stenosis and plaque in the dance group was significantly lower than the no-dance group. IMT was a significant positive correlation between PGC-1α and HCY in the no-dance group. Elderly individuals who regularly practiced Tibetan dance had improved blood vessel functionality and cerebral hemodynamic at high altitudes.

17.
J Phys Condens Matter ; 32(14): 145001, 2020 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-31855858

RESUMEN

Interface adhesion and stability between titanium and carbon materials have been investigated by first-principles calculation, in which three different DFT-PBE, DFT-LDA and optB88-vdW approaches are considered. Our calculation reveals that the formation of carbon vacancy in graphene would enhance the interface stability and increase interfacial strength, which may be due to a strong hybridization between titanium atom and the sp2 dangling bonds of the carbons near the vacancy. It is also found that the van der Waals interaction has less effects on cohesion properties of the titanium/graphite interfaces, and the Ti-C bond of titanium-carbon interfaces is weaker than that of the TiC bulk. The derived results are discussed in depth by means of electron distribution and Bader transfer analysis, and could be used as a guiding parameter for exploring the fundamental properties of titanium-carbon products as well as various potential applications.

18.
Mil Med Res ; 6(1): 12, 2019 04 30.
Artículo en Inglés | MEDLINE | ID: mdl-31036067

RESUMEN

BACKGROUND: The aim of this work is to detect and compare the peripheral blood miRNA expression profiles in patients with severe traumatic brain injury (sTBI) 2, 12, 24, 48, and 72 h after injury at high altitude and to predict the target genes of differential expressed miRNAs. METHODS: Twenty sTBI patients from high-altitude areas were randomly selected according to the inclusion and exclusion criteria and were divided into five groups: the 2-h group, 12-h group, 24-h group, 48-h group, and 72-h group. Peripheral blood miRNA expression profiles were detected using real-time quantitative PCR (qRT-PCR). RESULTS: The expression levels of miR-18a, miR-203, miR-146a, miR-149, miR-23b, and miR-let-7b in peripheral blood showed significant differences between the 2-h group and the 12-h group. The expression levels of miR-203, miR-146a, miR-149, miR-23b, and miR-let-7f in peripheral blood were up-regulated in the 24-h group. In the 48-h group, the expression levels of miR-181d, miR-29a, and miR-18b were upregulated. In the 72-h group, the expression levels of miR-203, miR-146a, miR-149, miR-23b, and miR-let-7f changed. The main target genes of the differentiation expressed miRNAs were genes that regulate inflammatory responses, apoptosis, and DNA damage/repair. CONCLUSIONS: miRNAs may be involved in the pathogenesis of sTBI by dynamically regulating the target genes that regulate inflammatory responses, apoptosis, and DNA damage/repair pathways.


Asunto(s)
Altitud , Lesiones Traumáticas del Encéfalo/genética , MicroARNs/genética , Adulto , Lesiones Traumáticas del Encéfalo/sangre , Daño del ADN , Femenino , Humanos , Masculino , MicroARNs/sangre , Persona de Mediana Edad , Estudios Prospectivos , Reacción en Cadena en Tiempo Real de la Polimerasa
19.
Exp Mol Med ; 51(3): 1-11, 2019 03 20.
Artículo en Inglés | MEDLINE | ID: mdl-30902967

RESUMEN

The goals of this study were to investigate the role of the Notch1/PDGFRß/ROCK1 signaling pathway in the pathogenesis of pulmonary fibrosis and to explore the possibility of treating fibrosis by targeting Notch1. Lung tissues from patients with pulmonary fibrosis were examined for the expression of Notch1/PDGFRß/ROCK1 using RT-qPCR, western blotting, and immunostaining. Cultured mouse lung pericytes were transfected with Notch1-overexpressed vectors or shRNA targeting PDGFRß/ROCK1 to examine cell behaviors, including proliferation, cell cycle arrest, and differentiation toward myofibroblasts. Finally, a mouse pulmonary fibrosis model was prepared, and a Notch1 inhibitor was administered to observe tissue morphology and pericyte cell behaviors. Human pulmonary fibrotic tissues presented with overexpression of Notch1, PDGFRß, and ROCK1, in addition to a prominent transition of pericytes into myofibroblasts. In cultured mouse lung pericytes, overexpression of Notch1 led to the accelerated proliferation and differentiation of cells, and it also increased the expression of the PDGFRß and ROCK1 proteins. The knockdown of PDGFRß/ROCK1 in pericytes remarkably suppressed pericyte proliferation and differentiation. As further substantiation, the administration of a Notch1 inhibitor in a mouse model of lung fibrosis inhibited the PDGFRß/ROCK1 pathway, suppressed pericyte proliferation and differentiation, and alleviated the severity of fibrosis. Our results showed that the Notch1 signaling pathway was aberrantly activated in pulmonary fibrosis, and this pathway may facilitate disease progression via mediating pericyte proliferation and differentiation. The inhibition of the Notch1 pathway may provide one promising treatment strategy for pulmonary fibrosis.


Asunto(s)
Fibrosis Pulmonar Idiopática/patología , Miofibroblastos/patología , Pericitos/patología , Receptor Notch1/metabolismo , Receptores del Factor de Crecimiento Derivado de Plaquetas/metabolismo , Quinasas Asociadas a rho/metabolismo , Animales , Diferenciación Celular , Proliferación Celular , Células Cultivadas , Humanos , Fibrosis Pulmonar Idiopática/metabolismo , Pulmón/metabolismo , Pulmón/patología , Ratones , Miofibroblastos/metabolismo , Pericitos/metabolismo , Receptor Notch1/análisis , Transducción de Señal
20.
Biotechnol Appl Biochem ; 66(3): 309-315, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30624798

RESUMEN

Oval cells, a kind of hepatic progenitor cell quiescent at normal condition, activates to proliferate and differentiate into hepatocytes under severe and long-term liver injury, which usually raises severe inflammation. However, how oval cell survives in the inflammatory milieu interne is still unclear. Tumor necrosis factor α (TNFα), mimicking inflammatory hepatic milieu interne, was used to treat oval cell line, WB-F344, to test the protective function of matrilin-2. In this study, our data suggested that matrilin-2 prevented TNFα-induced apoptosis in WB-F344 cells via inhibiting ASK1/MKK7/JNK pathway. In conclusion, we determined that matrilin-2 plays the key role in maintaining the survival of oval cell and guarantees its proliferation under various injury factors.


Asunto(s)
Apoptosis/efectos de los fármacos , Proteínas Quinasas JNK Activadas por Mitógenos/antagonistas & inhibidores , Factor de Necrosis Tumoral alfa/farmacología , Animales , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Proteínas Matrilinas/metabolismo , Ratas , Ratas Endogámicas F344
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