Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Resultados 1 - 20 de 82
Filtrar
1.
Nature ; 624(7991): 378-389, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38092917

RESUMEN

Recent advances in single-cell technologies have led to the discovery of thousands of brain cell types; however, our understanding of the gene regulatory programs in these cell types is far from complete1-4. Here we report a comprehensive atlas of candidate cis-regulatory DNA elements (cCREs) in the adult mouse brain, generated by analysing chromatin accessibility in 2.3 million individual brain cells from 117 anatomical dissections. The atlas includes approximately 1 million cCREs and their chromatin accessibility across 1,482 distinct brain cell populations, adding over 446,000 cCREs to the most recent such annotation in the mouse genome. The mouse brain cCREs are moderately conserved in the human brain. The mouse-specific cCREs-specifically, those identified from a subset of cortical excitatory neurons-are strongly enriched for transposable elements, suggesting a potential role for transposable elements in the emergence of new regulatory programs and neuronal diversity. Finally, we infer the gene regulatory networks in over 260 subclasses of mouse brain cells and develop deep-learning models to predict the activities of gene regulatory elements in different brain cell types from the DNA sequence alone. Our results provide a resource for the analysis of cell-type-specific gene regulation programs in both mouse and human brains.


Asunto(s)
Encéfalo , Cromatina , Análisis de la Célula Individual , Animales , Humanos , Ratones , Encéfalo/citología , Encéfalo/metabolismo , Corteza Cerebral/citología , Cromatina/química , Cromatina/genética , Cromatina/metabolismo , Aprendizaje Profundo , Elementos Transponibles de ADN/genética , Redes Reguladoras de Genes/genética , Neuronas/metabolismo
2.
Small ; : e2311204, 2024 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-38459801

RESUMEN

Constructing a flexible and chemically stable multifunctional layer for the lithium (Li) metal anodes is a highly effective approach to improve the uneven deposition of Li+ and suppress the dendrite growth. Herein, an organic protecting layer of polythiophene is in situ polymerized on the Li metal via plasma polymerization. Compared with the chemically polymerized thiophene (C-PTh), the plasma polymerized thiophene layer (P-PTh), with a higher Young's modulus of 8.1 GPa, shows strong structural stability due to the chemical binding of the polythiophene and Li. Moreover, the nucleophilic C─S bond of polythiophene facilitates the decomposition of Li salts in the electrolytes, promoting the formation of LiF-rich solid electrolyte interface (SEI) layers. The synergetic effect of the rigid LiF as well as the flexible PTh-Li can effectively regulate the uniform Li deposition and suppress the growth of Li dendrites during the repeated stripping-plating, enabling the Li anodes with long-cycling lifespan over 8000 h (1 mA cm-2 , 1 mAh cm-2) and 2500 h (10 mA cm-2 , 10 mAh cm-2 ). Since the plasma polymerization is facile (5-20 min) and environmentally friendly (solvent-free), this work offers a novel and promising strategy for the construction of the forthcoming generation of high-energy-density batteries.

3.
Chemistry ; 30(18): e202303892, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38279783

RESUMEN

The aggravation of energy problems and the scarcity of lithium resources have forced us to look for new energy storage systems. Aluminum ion batteries, as a promising energy storage system, have the advantages of environmental friendliness and abundant aluminum resources, and have the potential for application in large-scale energy storage and personal portable electronic devices. To solve the stability problem of aluminum ion batteries during cycling for large-scale energy storage needs, we report a polythiophene-based conductive polymer, poly(3,4-dimethylthiophene) (PDMT), as a high performance cathode material for aluminum ion batteries. By introducing two methyl groups on the thiophene ring, we successfully adjust the local charge density of the heterocyclic thiophene, thus changing the electron delocalization characteristics, and improving the electrochemical reaction activity of the polythiophene (PTH) material as a redox electrode material. This also maintains the symmetry and regularity of the polymer structure, giving the material better cycling stability. The discharge specific capacity reaches 110 mAh g-1 at a current density of 200 mA g-1, far exceeding conventional PTH cathodes (~70 mAh g-1), and the capacity retention rate is 92.7 % after 1000 cycles. It also shows excellent rate performance due to the flexible structure of the conductive polymer.

4.
J Enzyme Inhib Med Chem ; 39(1): 2318645, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38465731

RESUMEN

A series of novel benzimidazole derivatives were designed and synthesised based on the structures of reported oral available ALK inhibitor and HDAC inhibitor, pracinostat. In enzymatic assays, compound 3b, containing a 2-acyliminobenzimidazole moiety and hydroxamic acid side chain, could inhibit both ALK and HDAC6 (IC50 = 16 nM and 1.03 µM, respectively). Compound 3b also inhibited various ALK mutants known to be involved in crizotinib resistance, including mutant L1196M (IC50, 4.9 nM). Moreover, 3b inhibited the proliferation of several cancer cell lines, including ALK-addicted H2228 cells. To evaluate its potential for treating cancers in vivo, 3b was used in a human A549 xenograft model with BALB/c nude mice. At 20 mg/kg, 3b inhibited tumour growth by 85% yet had a negligible effect on mean body weight. These results suggest a attracting route for the further research and optimisation of dual ALK/HDAC inhibitors.


Asunto(s)
Antineoplásicos , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Ratones , Animales , Humanos , Quinasa de Linfoma Anaplásico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Inhibidores de Histona Desacetilasas/farmacología , Ratones Desnudos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/metabolismo , Proliferación Celular , Inhibidores de Proteínas Quinasas/química , Antineoplásicos/química , Línea Celular Tumoral
5.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 55(1): 132-138, 2024 Jan 20.
Artículo en Zh | MEDLINE | ID: mdl-38322530

RESUMEN

Objective: To investigate the effects of long-term administration of tacrolimus (also known as FK506) on the pain-related behaviors in mice and to study the underlying mechanism of pain induced by FK506 via measuring the effect of FK506 on the synaptic expression and phosphorylation of alpha-amino-3-hyroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor in the spinal cord dorsal horn of mice. Methods: 1) A total of 24 mice were evenly and randomly assigned to two groups, a FK506 group and a Saline group. The FK506 group was given daily intraperitoneal injection of FK506 and the Saline group received normal saline. Both groups received injection once a day for 7 days in a row. Some of the mice ( n=6 in each group) were monitored for the changes in the paw withdrawal threshold (PWT), the paw withdrawal latency (PWL), and the spontaneous pain behaviors to establish the pain model. The other mice ( n=6 in each group) of each group underwent isolation of the dorsal horn when obvious pain symptoms were induced on day 7 of injection. Then, immunoblotting was performed to determine the synaptic expression and phosphorylation levels of GluA1 and GluA2 subunits of AMPA receptors. 2) The mice were randomly divided into two groups, FK506+calcineurin (CaN) group and FK506+Saline group ( n=6 in each group). After the pain model was constructed, the mice were given intrathecal injection of recombinant CaN (also know as 33 U) or normal saline. Then, 60 minutes later, the PWT and the PWL of the mice were measured to investigate the role of CaN in FK506-induced pain. 3) Another18 mice were selected. The mice were randomly and evenly assigned to three groups, a control group (receiving intraperitoneal injection of normal saline followed by intrathecal injection of normal saline), FK506+Saline group (receiving intraperitoneal injection of FK506 followed by intrathecal injection of normal saline) and FK506+CaN group (receiving intraperitoneal injection of FK506 followed by intrathecal injection of CaN). Then, 60 minutes later, the spinal cords were isolated and subjected to immunoblotting assay to determine the role of CaN in FK506-induced AMPA receptor modification. Results: 1) After 7 consecutive days of intraperitoneal injection of FK506, the PWT and PWL of mice dropped significantly, reaching on day 7 as low as 22.3%±0.05% and 66.6%±0.05% of the control group, respectively ( P<0.01). The FK506-treated mice displayed evident spontaneous pain behavior, presenting significantly increased licking activities ( P<0.01). These results indicated that FK506-induced pain model was successfully established. Immunoblotting assay showed that the total expressions of GluA1 and GluA2 subunits in the spinal dorsal horn of the FK506 group remained unchanged in comparison with those of the Saline group. However, FK506 specifically induced an increase in the synaptic expression of GluA1. In addition, the phosphorylation levels of GluA1 at Ser845 and Ser831 in FK506-treated mice were significantly increased in comparison with those of the control group ( P<0.05). 2) Compared with those of the mice in the FK506+Saline group, the PWT and the PWL of mice in the FK506+CaN group were significantly increased ( P<0.05). 3) Compared with those of the FK506+Saline group, the synaptic expression of GluA1 were decreased in FK506+CaN group ( P<0.01) and the phosphorylation levels of GluA1 at Ser845 and Ser831 were significantly downregulated ( P<0.001). Conclusion: The hyper-expression and hyperphosphorylation of GluA1 subunit in the spinal cord dorsal horn resulting from CaN inhibition contributes to the FK506-induced pain syndrome. FK506 induces the synaptic hyper-expression and hyperphosphorylation of GluA1 in the dorsal horn of the spinal cord through CaN inhibition, thereby inducing pain.


Asunto(s)
Receptores AMPA , Tacrolimus , Ratones , Animales , Tacrolimus/metabolismo , Tacrolimus/farmacología , Receptores AMPA/metabolismo , Solución Salina/farmacología , Asta Dorsal de la Médula Espinal/metabolismo , Médula Espinal , Dolor/metabolismo
6.
Am J Physiol Endocrinol Metab ; 324(1): E97-E113, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36383639

RESUMEN

Glucagon-secreting pancreatic α-cells play pivotal roles in the development of diabetes. Glucagon promotes insulin secretion from ß-cells. However, the long-term effect of glucagon on the function and phenotype of ß-cells had remained elusive. In this study, we found that long-term glucagon intervention or glucagon intervention with the presence of palmitic acid downregulated ß-cell-specific markers and inhibited insulin secretion in cultured ß-cells. These results suggested that glucagon induced ß-cell dedifferentiation under pathological conditions. Glucagon blockage by a glucagon receptor (GCGR) monoclonal antibody (mAb) attenuated glucagon-induced ß-cell dedifferentiation. In primary islets, GCGR mAb treatment upregulated ß-cell-specific markers and increased insulin content, suggesting that blockage of endogenous glucagon-GCGR signaling inhibited ß-cell dedifferentiation. To investigate the possible mechanism, we found that glucagon decreased FoxO1 expression. FoxO1 inhibitor mimicked the effect of glucagon, whereas FoxO1 overexpression reversed the glucagon-induced ß-cell dedifferentiation. In db/db mice and ß-cell lineage-tracing diabetic mice, GCGR mAb lowered glucose level, upregulated plasma insulin level, increased ß-cell area, and inhibited ß-cell dedifferentiation. In aged ß-cell-specific FoxO1 knockout mice (with the blood glucose level elevated as a diabetic model), the glucose-lowering effect of GCGR mAb was attenuated and the plasma insulin level, ß-cell area, and ß-cell dedifferentiation were not affected by GCGR mAb. Our results proved that glucagon induced ß-cell dedifferentiation under pathological conditions, and the effect was partially mediated by FoxO1. Our study reveals a novel cross talk between α- and ß-cells and is helpful to understand the pathophysiology of diabetes and discover new targets for diabetes treatment.NEW & NOTEWORTHY Glucagon-secreting pancreatic α-cells can interact with ß-cells. However, the long-term effect of glucagon on the function and phenotype of ß-cells has remained elusive. Our new finding shows that long-term glucagon induces ß-cell dedifferentiation in cultured ß-cells. FoxO1 inhibitor mimicks whereas glucagon signaling blockage by GCGR mAb reverses the effect of glucagon. In type 2 diabetic mice, GCGR mAb increases ß-cell area, improves ß-cell function, and inhibits ß-cell dedifferentiation, and the effect is partially mediated by FoxO1.


Asunto(s)
Diabetes Mellitus Experimental , Insulinas , Ratones , Animales , Receptores de Glucagón/metabolismo , Glucagón/metabolismo , Glucemia/metabolismo , Diabetes Mellitus Experimental/metabolismo , Desdiferenciación Celular , Ratones Noqueados , Insulina/metabolismo , Proteína Forkhead Box O1
7.
Diabetes Metab Res Rev ; 39(3): e3607, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36565185

RESUMEN

AIMS: Sodium-glucose co-transporter 2 inhibitors, including dapagliflozin, improve ß cell function in type 2 diabetic individuals. Whether dapagliflozin can protect islet microvascular endothelial cells (IMECs) and thus contribute to the improvement of ß cell function remains unknown. MATERIALS AND METHODS: The db/db mice were treated with dapagliflozin or vehicle for 6 weeks. ß cell function, islet capillaries and the levels of inflammatory chemokines in IMECs were detected. The mouse IMEC cell line MS-1 cells were incubated with palmitate and/or dapagliflozin for 24 h. Angiogenesis and inflammatory chemokine levels were evaluated, and the involved signalling pathways were analysed. The mouse ß cell line MIN6 cells, in the presence or absence of co-culture with MS-1 cells, were treated with palmitate and/or dapagliflozin for 24 h. The expression of ß cell specific markers and insulin secretion in MIN6 cells were determined. RESULTS: Dapagliflozin significantly improved ß cell function, increased islet capillaries and decreased the levels of inflammatory chemokines of IMECs in db/db mice. In the palmitate-treated MS-1 cells, angiogenesis was enhanced and the levels of inflammatory chemokines were downregulated by dapagliflozin. Either a PI3K inhibitor or mTOR inhibitor eliminated the dapagliflozin-mediated effects. Importantly, dapagliflozin attenuated the palmitate-induced downregulation of ß cell function-related gene expression and insulin secretion in MIN6 cells co-cultured with MS-1 cells but not in those on mono-culture. CONCLUSIONS: Dapagliflozin restores islet vascularisation and attenuates the inflammation of IMECs in type 2 diabetic mice. The dapagliflozin-induced improvement of ß cell function is at least partially accounted for by its beneficial effects on IMECs in a PI3K/Akt-mTOR-dependent manner.


Asunto(s)
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Islotes Pancreáticos , Enfermedades Vasculares , Ratones , Animales , Diabetes Mellitus Experimental/tratamiento farmacológico , Diabetes Mellitus Experimental/metabolismo , Células Endoteliales , Fosfatidilinositol 3-Quinasas/metabolismo , Islotes Pancreáticos/metabolismo , Compuestos de Bencidrilo/farmacología , Enfermedades Vasculares/metabolismo , Palmitatos/metabolismo
8.
Mol Psychiatry ; 26(3): 835-848, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-30976086

RESUMEN

Many psychiatric disorders are characterized by a strong sex difference, but the mechanisms behind sex-bias are not fully understood. DNA methylation plays important roles in regulating gene expression, ultimately impacting sexually different characteristics of the human brain. Most previous literature focused on DNA methylation alone without considering the regulatory network and its contribution to sex-bias of psychiatric disorders. Since DNA methylation acts in a complex regulatory network to connect genetic and environmental factors with high-order brain functions, we investigated the regulatory networks associated with different DNA methylation and assessed their contribution to the risks of psychiatric disorders. We compiled data from 1408 postmortem brain samples in 3 collections to identify sex-differentially methylated positions (DMPs) and regions (DMRs). We identified and replicated thousands of DMPs and DMRs. The DMR genes were enriched in neuronal related pathways. We extended the regulatory networks related to sex-differential methylation and psychiatric disorders by integrating methylation quantitative trait loci (meQTLs), gene expression, and protein-protein interaction data. We observed significant enrichment of sex-associated genes in psychiatric disorder-associated gene sets. We prioritized 2080 genes that were sex-biased and associated with psychiatric disorders, such as NRXN1, NRXN2, NRXN3, FDE4A, and SHANK2. These genes are enriched in synapse-related pathways and signaling pathways, suggesting that sex-differential genes of these neuronal pathways may cause the sex-bias of psychiatric disorders.


Asunto(s)
Metilación de ADN , Trastornos Mentales , Encéfalo , Islas de CpG/genética , Metilación de ADN/genética , Epigénesis Genética , Femenino , Humanos , Masculino , Trastornos Mentales/genética , Sitios de Carácter Cuantitativo
9.
J Cell Mol Med ; 25(17): 8432-8441, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34302427

RESUMEN

High myopia is one of the leading causes of visual impairment worldwide with high heritability. We have previously identified the genetic contribution of SLC39A5 to nonsyndromic high myopia and demonstrated that disease-related mutations of SLC39A5 dysregulate the TGF-ß pathway. In this study, the mechanisms underlying SLC39A5 involvement in the pathogenesis of high myopia are determined. We observed the morphogenesis and migration abnormalities of the SLC39A5 knockout (KO) human embryonic kidney cells (HEK293) and found a significant injury of ECM constituents. RNA-seq and qRT-PCR revealed the transcription decrease in COL1A1, COL2A1, COL4A1, FN1 and LAMA1 in the KO cells. Further, we demonstrated that TGF-ß signalling, the regulator of ECM, was inhibited in SLC39A5 depletion situation, wherein the activation of receptor Smads (R-Smads) via phosphorylation was greatly blocked. SLC39A5 re-expression reversed the phenotype of TGF-ß signalling and ECM synthesis in the KO cells. The fact that TGF-ß signalling was zinc-regulated and that SLC39A5 was identified as a zinc transporter urged us to check the involvement of intracellular zinc in TGF-ß signalling impairment. Finally, we determined that insufficient zinc chelation destabilized Smad proteins, which naturally inhibited TGF-ß signalling. Overall, the SLC39A5 depletion-induced zinc deficiency destabilized Smad proteins, which inhibited the TGF-ß signalling and downstream ECM synthesis, thus contributing to the pathogenesis of high myopia. This discovery provides a deep insight into myopic development.


Asunto(s)
Proteínas de Transporte de Catión/fisiología , Matriz Extracelular/metabolismo , Miopía/metabolismo , Proteínas Smad/metabolismo , Zinc/metabolismo , Células HEK293 , Humanos , Mutación
10.
Mol Psychiatry ; 25(11): 2672-2684, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32826963

RESUMEN

Genome-wide association studies (GWASs) have identified numerous single nucleotide polymorphisms (SNPs) associated with bipolar disorder (BD), but what the causal variants are and how they contribute to BD is largely unknown. In this study, we used FUMA, a GWAS annotation tool, to pinpoint potential causal variants and genes from the latest BD GWAS findings, and performed integrative analyses, including brain expression quantitative trait loci (eQTL), gene coexpression network, differential gene expression, protein-protein interaction, and brain intermediate phenotype association analysis to identify the functions of a prioritized gene and its connection to BD. Convergent lines of evidence prioritized protein-coding gene G Protein Nucleolar 3 (GNL3) as a BD risk gene, with integrative analyses revealing GNL3's roles in cell proliferation, neuronal functions, and brain phenotypes. We experimentally revealed that BD-related eQTL SNPs rs10865973, rs12635140, and rs4687644 regulate GNL3 expression using dual luciferase reporter assay and CRISPR interference experiment in human neural progenitor cells. We further identified that GNL3 knockdown and overexpression led to aberrant neuronal proliferation and differentiation, using two-dimensional human neural cell cultures and three-dimensional forebrain organoid model. This study gathers evidence that BD-related genetic variants regulate GNL3 expression which subsequently affects neuronal proliferation and differentiation.


Asunto(s)
Trastorno Bipolar/genética , Proteínas de Unión al GTP/genética , Predisposición Genética a la Enfermedad/genética , Proteínas Nucleares/genética , Estudio de Asociación del Genoma Completo , Humanos , Polimorfismo de Nucleótido Simple/genética , Sitios de Carácter Cuantitativo/genética
11.
J Chem Phys ; 154(10): 104705, 2021 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-33722010

RESUMEN

In this article, a systematic examination of the electronic and optical properties of partially fluorinated graphene is presented. In order to capture a large variety of fluorination degrees and configurations, different sizes of the supercell combining with various degrees of fluorination are considered. On top of periodic density functional theory, the G0W0 method and the G0W0Γ method within many-body Green's function framework are employed. Including the description of electron-hole interactions, the optical spectra based on the Bethe-Salpeter equation are calculated. Two-sided fluorination with compact fluorination arrangements is energetically most favorable. The fluorination degree has a determined impact on the bandgap value in the system, while the fluorination pattern strongly influences the characteristics of the bands in the electronic structures. Depending on the polarization of the applied electromagnetic field, the optical absorption spectra of the same structure could vary significantly. These interesting results suggest the potential applications of partially fluorinated graphene as optoelectronic materials.

12.
Bioinformatics ; 35(1): 172-174, 2019 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-29985970

RESUMEN

Summary: Gene expression changes over the lifespan and varies among different tissues or cell types. Gene co-expression also changes by sex, age, different tissues or cell types. However, gene expression under the normal state and gene co-expression in the human brain has not been fully defined and quantified. Here we present a database named Brain EXPression Database (BrainEXP) which provides spatiotemporal expression of individual genes and co-expression in normal human brains. BrainEXP consists of 4567 samples from 2863 healthy individuals gathered from existing public databases and our own data, in either microarray or RNA-Seq library types. We mainly provide two analysis results based on the large dataset: (i) basic gene expression across specific brain regions, age ranges and sexes; (ii) co-expression analysis from different platforms. Availability and implementation: http://www.brainexp.org/. Supplementary information: Supplementary data are available at Bioinformatics online.


Asunto(s)
Encéfalo/crecimiento & desarrollo , Bases de Datos Genéticas , Perfilación de la Expresión Génica , Biología Computacional , Humanos , ARN , Análisis de Secuencia de ARN
13.
Phys Chem Chem Phys ; 22(21): 11936-11942, 2020 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-32409806

RESUMEN

First-principle calculations within many-body perturbation theory are carried out to investigate the influence of the adsorbed molecules and sulfur (S) defects on the electronic and optical properties of the MoS2 monolayer. The exciton binding energy in the range of 0.05 eV to 1.14 eV is observed as a function of molecular coverage, when NO and 1,3,5-triazin (C3H3N3) are adsorbed on the pristine surface. These results can be explained by the interaction between the exciton and the adsorbed molecule. Furthermore, the combined effect of molecular functionalization and defective doping is studied. Our results show that both the electronic and optical band gaps of the MoS2 monolayer strongly depend on the molecular species and the defective coverage, and can be tuned up to ∼2 eV. This work demonstrates the great potential of controlling the MoS2 monolayer's excitonic properties by molecular functionalization and defective engineering.

14.
Nature ; 514(7522): 348-50, 2014 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-25252975

RESUMEN

The ability to store energy on the electric grid would greatly improve its efficiency and reliability while enabling the integration of intermittent renewable energy technologies (such as wind and solar) into baseload supply. Batteries have long been considered strong candidate solutions owing to their small spatial footprint, mechanical simplicity and flexibility in siting. However, the barrier to widespread adoption of batteries is their high cost. Here we describe a lithium-antimony-lead liquid metal battery that potentially meets the performance specifications for stationary energy storage applications. This Li||Sb-Pb battery comprises a liquid lithium negative electrode, a molten salt electrolyte, and a liquid antimony-lead alloy positive electrode, which self-segregate by density into three distinct layers owing to the immiscibility of the contiguous salt and metal phases. The all-liquid construction confers the advantages of higher current density, longer cycle life and simpler manufacturing of large-scale storage systems (because no membranes or separators are involved) relative to those of conventional batteries. At charge-discharge current densities of 275 milliamperes per square centimetre, the cells cycled at 450 degrees Celsius with 98 per cent Coulombic efficiency and 73 per cent round-trip energy efficiency. To provide evidence of their high power capability, the cells were discharged and charged at current densities as high as 1,000 milliamperes per square centimetre. Measured capacity loss after operation for 1,800 hours (more than 450 charge-discharge cycles at 100 per cent depth of discharge) projects retention of over 85 per cent of initial capacity after ten years of daily cycling. Our results demonstrate that alloying a high-melting-point, high-voltage metal (antimony) with a low-melting-point, low-cost metal (lead) advantageously decreases the operating temperature while maintaining a high cell voltage. Apart from the fact that this finding puts us on a desirable cost trajectory, this approach may well be more broadly applicable to other battery chemistries.

15.
J Anim Physiol Anim Nutr (Berl) ; 104(4): 1096-1105, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31724241

RESUMEN

This experiment was conducted to evaluate the effects of astragalus polysaccharides (Aps) and ginseng polysaccharide (Gps) on growth performance, liver function, immune function, TLR4 signalling pathways and intestinal barrier in weaned piglets challenged with lipopolysaccharide (LPS). In an experiment spanning 28 days, 180 weaned piglets were randomly divided into three treatment groups: basal diet (Con), basal diet supplemented with 800 mg/kg Gps (Gps) and basal diet supplemented with 800 mg/kg Aps (Aps). At the end of the experiment, 12 piglets of each group were selected; half (n = 6) were intraperitoneally injected with LPS and half with normal saline. Dietary supplementation with Aps and Gps significantly increased (p < .05) the average daily gain and feed conversion rate. Lipopolysaccharide challenge increased (p < .05) expression of serum urea nitrogen (BUN), alanine aminotransferase (ALT), aspartate aminotransferase (AST), interleukin-1ß (IL-1ß) and tumour inflammatory factor-α (TNF-α), but decreased (p < .05) serum superoxide dismutase (SOD) level, total antioxidant capacity (T-AOC) and immunoglobulin A (IgA) expression. Lipopolysaccharide-challenged piglets fed with Aps or Gps had lower (p < .05) BUN, ALT, AST, IL-1ß and TNF-α levels and greater (p < .05) SOD, T-AOC and IgA levels. Lipopolysaccharide challenge increased (p < .05) the expression of TLR4, MyD88 and NF-κB, and LPS-challenged piglets fed diets supplemented with Aps or Gps increased TLR4 and MyD88 and decreased NF-κB expression. Lipopolysaccharide challenge reduced (p < .05) the jejunal villus height, and piglets fed with Aps or Gps had increased (p < .05) jejunal villus height. Supplementation with Aps or Gps enhanced the expression of occludin and claudin in challenged or unchallenged piglets. In conclusion, dietary supplementation with Aps or Gps enhanced piglet growth performance, alleviated liver dysfunction and reduced immunological stress caused by LPS, as well as increased the intestinal barrier function.


Asunto(s)
Planta del Astrágalo/química , Lipopolisacáridos/toxicidad , Panax/química , Polisacáridos/farmacología , Porcinos/fisiología , Animales , Antioxidantes/metabolismo , Suplementos Dietéticos , Inmunoglobulinas/metabolismo , Hígado/efectos de los fármacos , Hígado/metabolismo , Polisacáridos/química , Porcinos/crecimiento & desarrollo , Porcinos/inmunología
16.
Hum Genet ; 137(2): 141-150, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29356939

RESUMEN

Reticulon 3 (RTN3) is a neuronally-expressed reticulon family protein that was previously shown to negatively regulate BACE1, a protease that is required for the generation of ß-amyloid peptides (Aß) from amyloid precursor protein. Despite biochemical and morphological evidence that supports a role of RTN3 in the formation of neuritic amyloid plaques, no systematic analyses of RTN3 mutations in patients with Alzheimer's disease (AD) have yet been reported. RTN3 were targeted sequenced in 154 sporadic early-onset and 285 late-onset AD patients. Luciferase reporter assay and kymographs were performed to analysis the expression of RNT3 and BACE1-RFP particle mobility on cells transfected with wild-type or variants RTN3 constructs. We identified heterozygous variants such as c.-8G > T, c.17C > A, c.42C > T, and c.116C > T from patients in the early-onset AD group and c.-8G > T, c.17C > A, from patients in the late-onset AD group. Such variants of RTN3 were not observed in control individuals. Further biochemical studies show that the RTN3 c.-8G > T variant in the 5'-untranslated region appears to cause reduced expression of RTN3. The RTN3 c.116 C > T variant causes a change of codon T39 to M39 (T39 M). Overexpression of RTN3 T39 M in cultured neurons led to impaired axonal transport of BACE1. The variants found in this study are likely genetic modifiers for RTN3-mediated formation of neuritic plaques in AD.


Asunto(s)
Enfermedad de Alzheimer/genética , Secretasas de la Proteína Precursora del Amiloide/genética , Péptidos beta-Amiloides/genética , Ácido Aspártico Endopeptidasas/genética , Proteínas Portadoras/genética , Proteínas de la Membrana/genética , Proteínas del Tejido Nervioso/genética , Adulto , Anciano , Enfermedad de Alzheimer/fisiopatología , Precursor de Proteína beta-Amiloide/genética , Animales , Transporte Axonal/genética , Encéfalo/metabolismo , Encéfalo/patología , Femenino , Regulación de la Expresión Génica/genética , Humanos , Masculino , Ratones , Ratones Noqueados , Persona de Mediana Edad , Mutación , Neuronas/metabolismo , Neuronas/fisiología
17.
J Chem Phys ; 149(18): 184101, 2018 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-30441917

RESUMEN

Previously, we have proposed a method, FPA-M, for focal-point analysis of magnetic parameter calculations [Sun et al., J. Chem. Phys. 138, 124113 (2013)], where the shielding constants at equilibrium geometries σe are calculated with the second order Møller-Plesset perturbation (MP2) approach, which are extrapolated to the complete basis set (CBS) limit and then augmented by the [σe(CCSD(T)) - σe(MP2)] difference at a valence triple-ζ (VTZ) basis set, where CCSD(T) stands for the coupled cluster singles and doubles model with a perturbative correction for triple excitations. This FPA-M(MP2) method provides satisfactory results to approach to the corresponding CCSD(T)/CBS values for elements of the first two rows in the periodic tables. A series of extensions have been explored here, which replace the MP2/CBS with the Hartree-Fock (HF)/CBS for efficiency. In particular, the [σe(CCSD(T)) - σe(MP2)] VTZ difference is replaced by a step-wise correction from the [σe(CCSD(T)) - σe(MP2)] difference at a valence double-ζ basis set plus the [σe(MP2) - σe(HF)] VTZ difference, leading to a new scheme, denoted here as FPA-M(HF'). A systematical comparison has demonstrated that the FPA-M(HF') method provides an excellent balance between accuracy and efficiency, which makes routinely accurate calculations of the shielding constants for medium-sized organic molecules and biomolecules feasible.

18.
Zhonghua Wai Ke Za Zhi ; 54(1): 25-9, 2016 Jan 01.
Artículo en Zh | MEDLINE | ID: mdl-26792349

RESUMEN

OBJECTIVE: To verify the clinical safety of complete mesocolic excision (CME) and manufacture pathological large slices. METHODS: A prospective analysis clinical data of 85 right colon cancer in patients by the same group of surgeons at the Department of General Surgery, Beijing Friendship Hospital, Capital Medical University from January 2012 to December 2013 which were divided into two groups: CME group (n=39) and traditional radical operation group (n=46) by surgical approach. CME group and control group were compared the differences of clinic and pathologic variables, precise tissues morphometry, lymph nodes harvest, mesocolic area and so on. By comparison to operation time, blood loss, postoperative complications, flatus restoring time, drainage removal time and length of stay, the security of CME was analyzed. Statistical methods included independent sample t-test, Wilcoxon rank sum test and χ(2) test. In order to manufacture pathological large slices, the CME operation specimens were fixed. The large slices were stained by routine HE staining to detection of circumferential resection margin. RESULTS: Mean number of total lymph nodes was increased obviously in CME group (26.8±1.9 vs. 23.2±3.4, t=4.261, P=0.000). Mean number of lymph nodes of stage Ⅰ, Ⅱ were different between two groups (25.8±3.6 vs. 18.2±4.5, 26.8±7.7 vs. 24.9±6.2, t=8.776, 2.802, P=0.000). The positive lymph nodes of CME group was higher than control group (4(7) vs. 1.5(2), P=0.032), above all with statistically significant difference. Comparing CME group with the control group, there were the larger area of mesentery ((15 555±1 263) mm(2) vs. (12 493±1 002) mm(2,) t=12.456, P=0.000), the greater distance between the tumor and the high vascular tie ((116±22) mm vs. (82±11) mm, t=9.295, P=0.000), the greater distance between the normal bowel and the high vascular tie ((92±17) mm vs. (74±10) mm, t=8.132, P=0.000) of CME, with statistically significant difference. There were no statistically significant differences from operation safety when CME group was compared with the control group. The pathological large slices of colon cancer were prepared successfully and dyed evenly than those large slices were used to observe whether the lymph tube and lymph node metastasis inside the mesocolon. Existence of direct tumor invasion could be confirmed by investigating the large slices. Cancer embolus in intravascular and micro infiltration in mesocolon also could be found. CONCLUSIONS: CME operation can get the standard excision according the mesocolic area and integrity, as well as to harvest the maximum number of lymph node. The clinical application of CME is safe and does not increase the risk of operation. Circumferential resection margins can be detected by pathological large slices.


Asunto(s)
Colectomía , Neoplasias del Colon/cirugía , Mesocolon/cirugía , Remoción de Dispositivos , Humanos , Escisión del Ganglio Linfático , Ganglios Linfáticos , Metástasis Linfática , Tempo Operativo , Complicaciones Posoperatorias , Estudios Prospectivos
19.
Horm Behav ; 70: 38-46, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25736535

RESUMEN

The expression of food-anticipatory activity (FAA) is induced by restricted feeding (RF), and its entrainment requires food-entrainable oscillators, the neuroanatomical basis of which is currently unclear. Although RF impacts various hormones, sex-related differences in FAA are unclear. 'Here, we report significantly more food-anticipatory wheel-running activity in male than in female mice during RF. In parallel with the sex-related difference in FAA, male and female mice display different food intake and body weight in response to RF. Since gonadal hormones could be involved in the sex-specific difference in FAA, we compared sham and gonadectomized male and female wild-type mice. In gonadectomized mice, the sex difference in FAA was abolished, indicating a role for gonadal hormones in FAA. Further, plasma concentrations of the hormone ghrelin were higher in female than in male mice during ad libitum (AL) feeding, and RF induced a temporal advance in its peak in both sexes. RF also shifted the expression peak of the circadian gene mPer1 in the hippocampus and liver, although no sex difference was found in either the level or the cyclic phase of its expression. Per1(Brdm1) mutant mice were still sexually dimorphic for FAA, but diminished FAA was noted in both male and female Per2(Brdm1) mutant mice. In summary, our results imply that gonadal hormones contribute to the sex difference in FAA, possibly through modulating ghrelin activity.


Asunto(s)
Anticipación Psicológica/fisiología , Conducta Alimentaria/fisiología , Animales , Peso Corporal , Ingestión de Alimentos , Femenino , Alimentos , Ghrelina/metabolismo , Hormonas Esteroides Gonadales/fisiología , Masculino , Ratones , Ratones Endogámicos C57BL , Actividad Motora , Orquiectomía , Ovariectomía , Proteínas Circadianas Period/metabolismo , Caracteres Sexuales
20.
J Colloid Interface Sci ; 674: 603-611, 2024 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-38945027

RESUMEN

Rechargeable magnesium battery is regarded as the promising candidate for the next generation of high-specific-energy storage systems. Nevertheless, issues related to severe Mg-Cl dissociation at the electrolyte-electrode interface impede the insertion of Mg2+ into most materials, leading to severe polarization and low utilization of Mg-storage electrodes. In this study, a metal-organic polymer (MOP) Ni-TABQ (Ni-coordinated tetramino-benzoquinone) with superior surface catalytic activity is proposed to achieve the high-capacity Mg-MOP battery. The layered Ni-TABQ cathode, featuring a unique 2D π-d linear conjugated structure, effectively reduces the dissociation energy of MgxCly clusters at the Janus interface, thereby facilitating Mg2+ insertion. Due to the high utilization of active sites, Ni-TABQ achieves high capacities of 410 mAh/g at 200 mA g-1, attributable to a four-electron redox process involving two redox centers, benzoid carbonyls, and imines. This research highlights the importance of surface electrochemical processes in rechargeable magnesium batteries and paves the way for future development in multivalent metal-ion batteries.

SELECCIÓN DE REFERENCIAS
Detalles de la búsqueda