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1.
Langmuir ; 39(31): 11119-11133, 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37494475

RESUMO

For decades, our understanding of water-metal bonding has been dominated by the frontier orbital principle in which globally stable water-metal interactions are ruled by HOMO interacting with metal surfaces. Using density functional theory calculations, herein, we have revealed that the frontier orbital principle cannot be applied to metastable water bonding on Pt(111), where the decisive role of HOMO is replaced by HOMO-1 in terms of the greatest orbital shifts and depopulations as the two different bonding indicators. Unlike the stable water configuration in which both HOMO-1 and HOMO prefer to overlap with metal states through σ-like orbital interactions, metastable configurations exhibit delicate competition or balance between σ-like and π-like orbital interactions exerted by HOMO-1 and HOMO, respectively. These findings have significantly deepened our understanding of orbital roles in water-metal bonding interactions and bridged the gap between theoretical understanding of electrified waters at electrochemical interfaces and water science on metal surfaces.

2.
World J Urol ; 41(2): 501-508, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36581769

RESUMO

PURPOSE: To compare the perioperative and oncologic outcomes between minimally invasive pelvic organ-preserving radical cystectomy (MIPOPRC) and open pelvic organ-preserving radical cystectomy (open POPRC) among female patients with bladder cancer (BCa). METHODS: We identified female patients who underwent POPRC for BCa at three centers between January 2006 and April 2018. Female patients who underwent open POPRC were matched with those who underwent MIPOPRC using 1:1 propensity score (PS) matching. The patient demographics and perioperative and oncologic outcomes were evaluated for the comparison between MIPOPRC and open POPRC. RESULTS: Among the 158 patients enrolled, 83 patients underwent MIPOPRC, and 75 underwent open POPRC. A total of 60 MIPOPRC and 60 open POPRC patients were matched successfully. The cancer-specific survival (CSS) and recurrence-free survival (RFS) did not differ significantly in the propensity score-weighted cohort (p = 0.297 and p = 0.600, respectively). Subgroup analysis by age and pathologic stage in the matched cohort revealed that CSS and RFS were with no differences among all subgroups. Moreover, multivariable Cox regression analyses showed that the surgical approach (MIPOPRC vs open POPRC) was not a predictor of CSS (p = 0.250). CONCLUSION: MIPOPRC was non-inferior to open POPRC in terms of oncologic outcomes among female patients. MIPOPRC could be technically feasible in selected female patients with BCa.


Assuntos
Cistectomia , Neoplasias da Bexiga Urinária , Humanos , Feminino , Cistectomia/efeitos adversos , Pontuação de Propensão , Resultado do Tratamento , Bexiga Urinária/cirurgia , Neoplasias da Bexiga Urinária/patologia
3.
Sci Adv ; 8(34): eadc9961, 2022 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-36001665

RESUMO

Lithium (Li) metal anode have shown exceptional potential for high-energy batteries. However, practical cell-level energy density of Li metal batteries is usually limited by the low areal capacity (<3 mAh cm-2) because of the accelerated degradation of high-areal capacity Li metal anodes upon cycling. Here, we report the design of hyperbranched vertical arrays of defective graphene for enduring deep Li cycling at practical levels of areal capacity (>6 mAh cm-2). Such atomic-to-macroscopic trans-scale design is rationalized by quantifying the degradation dynamics of Li metal anodes. High-energy Li metal cells are prototyped under realistic conditions with high cathode capacity (>4 mAh cm-2), low negative-to-positive electrode capacity ratio (1:1), and low electrolyte-to-capacity ratio (5 g Ah-1), which shed light on a promising move toward practical Li metal batteries.

4.
J Hazard Mater ; 435: 129073, 2022 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-35650731

RESUMO

Photocatalysis is believed to be an important way of reducing NO pollutant in air and the facet engineering of semiconducting oxides could enhance the efficiency of the photocatalysis. ZnO nanoparticles with different exposed crystalline facets were successfully synthesized using a hydrothermal method and their photocatalytic degradation towards NO was investigated. The crystals from ZnCl2 precursor were hexagonal mesoporous ones with exposed (0002) facet, while those from zinc acetate were in the form of flakes or wheat ears with enhanced exposure of (101(-)1) facet. Calcination in air imparted an enhanced the textural coefficient of the orientated facets as well as the oxygen defects. The nanocrystals with enhanced (0002) facet and lower flat-band energy did better in photoelectrochemical water-oxidation than those with exposed (101(-)1) facet that showed superior photocatalytic activity (approaching 76.7 ± 0.6% under 365 nm photons) for NO oxidation. According to theoretical calculations, (101(-)1) facet with O termination showed much higher affinity to NO molecules than other configurations, and the oxygen vacancy in ZnO played an minor role in the photocatalytic oxidation of NO. A high quantum efficiency approaching 97.5 ± 1.4% under 275 nm photons was obtained for the ZnO crystals from zinc acetate with mixed (0002) and (101(-)1) facets. This research explores the special characteristics of ZnO with different exposed facets and is important for the future design of highly efficient photocatalyst for hazardous material removal.


Assuntos
Óxido de Zinco , Oxigênio , Acetato de Zinco , Óxido de Zinco/química
5.
Int Urol Nephrol ; 54(7): 1537-1543, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35552976

RESUMO

PURPOSE: To evaluate urinary outcomes of pelvic construction and lateral capsule sparing techniques in robot-assisted radical cystectomy with orthotopic ileal neobladder (RARC-OIN). METHODS: A total of 107 male patients who underwent RARC-OIN during January 2017 and February 2021 in Sun Yat-sen Memorial Hospital were analyzed retrospectively. Standard RARC-OIN with or without nerve sparing technique was performed in 44 patients (standard group), lateral prostate capsule sparing technique was performed in 20 patients (LCS group), combined pelvic reconstruction (CPR) technique including anterior suspension and posterior reconstruction were performed in 43 patients (CPR group). The urinary function was assessed by the use of pads and the Bladder Cancer Index (BCI). Continence was defined as the use of 0-1 pad during daytime or night-time. RESULTS: There was no statistical difference between the three groups regarding demographic, perioperative, and pathological data. Continence rates were 6.8, 50.0 and 34.9% for daytime, 4.6, 40.0 and 32.6% for night-time in the standard group, LCS group and CPR group at 1 month post-operation, respectively. Continence rates were 34.1, 80.0 and 69.8% for daytime, 27.3, 75.0 and 65.1% for night-time in the standard group, LCS group and CPR group at 3 month post-operation, respectively. No statistically significant difference was observed in the daytime and night-time continence rates at 12 months. CONCLUSIONS: Lateral capsule-sparing and combined pelvic reconstruction techniques are feasible to improve early daytime and night-time continence rates in RARC with orthotopic neobladder. CLINICAL TRIAL REGISTRATION: The trial registration number: ChiCTR2100047606.


Assuntos
Robótica , Neoplasias da Bexiga Urinária , Derivação Urinária , Cistectomia/efeitos adversos , Cistectomia/métodos , Humanos , Masculino , Próstata/patologia , Estudos Retrospectivos , Resultado do Tratamento , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/cirurgia , Derivação Urinária/métodos
7.
Molecules ; 26(23)2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34885680

RESUMO

An air pollution detector is proposed based on a tube-shaped single-electron transistor (SET) sensor. By monitoring the flow control component of the detector, each air pollutant molecule can be placed at the center of a SET nanopore and is treated as an island of the SET device in the same framework. Electron transport in the SET was incoherent, and the performances of the SET were sensitive at the single molecule level. Employing first-principles calculations, electronic features of an air pollutant molecule within a tube-shaped SET environment were found to be independent of the molecule rotational orientations with respect to axis of symmetry, unlike the electronic features in a conventional SET environment. Charge stability diagrams of the island molecules were demonstrated to be distinct for each molecule, and thus they can serve as electronic fingerprints for detection. Using the same setup, quantification of the air pollutant can be realized at room temperature as well. The results presented herein may help provide guidance for the identification and quantification of various types of air pollutants at the molecular level by treating the molecule as the island of the SET component in the proposed detector.

8.
ACS Appl Mater Interfaces ; 13(39): 47081-47089, 2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34565145

RESUMO

In thermoelectrics, the material's performance stems from a delicate tradeoff between atomic order and disorder. Generally, dopants and thus atomic disorder are indispensable for optimizing the carrier concentration and scatter short-wavelength heat-carrying phonons. However, the strong disorder has been perceived as detrimental to the semiconductor's electrical conductivity owing to the deteriorated carrier mobility. Here, we report the sustainable role of strong atomic disorder in suppressing the detrimental phase transition and enhancing the thermoelectric performance in GeTe. We found that AgSnSe2 and Sb co-alloying eliminates the unfavorable phase transition due to the high configurational entropy and achieve the cubic Ge1-x-ySbyTe1-x(AgSnSe2)x solid solutions with cationic and anionic site disorder. Though AgSnSe2 substitution drives the carrier mean free path toward the Ioffe-Regel limit and minimizes the carrier mobility, the increased carrier concentration could render a decent electrical conductivity, affording enough phase room for further performance optimization. Given the lowermost carrier mean free path, further Sb alloying on Ge sites was implemented to progressively optimize the carrier concentration and enhance the density-of-state effective mass, thereby substantially enhancing the Seebeck coefficient. In addition, the high density of nanoscale strain clusters induced by strong atomic disorders significantly restrains the lattice thermal conductivity. As a result, a state-of-the-art zT ≈ 1.54 at 773 K was attained in cubic Ge0.58Sb0.22Te0.8(AgSnSe2)0.2. These results demonstrate that the strong atomic disorder at the high entropy scale is a previously underheeded but promising approach in thermoelectric material research, especially for the numerous low carrier mobility materials.

9.
Proc Natl Acad Sci U S A ; 118(38)2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34521755

RESUMO

Rechargeable magnesium batteries represent a viable alternative to lithium-ion technology that can potentially overcome its safety, cost, and energy density limitations. Nevertheless, the development of a competitive room temperature magnesium battery has been hindered by the sluggish dissociation of electrolyte complexes and the low mobility of Mg2+ ions in solids, especially in metal oxides that are generally used in lithium-ion batteries. Herein, we introduce a generic proton-assisted method for the dissociation of the strong Mg-Cl bond to enable genuine Mg2+ intercalation into an oxide host lattice; meanwhile, the anisotropic Smoluchowski effect produced by titanium oxide lattices results in unusually fast Mg2+ diffusion kinetics along the atomic trough direction with a record high ion conductivity of 1.8 × 10-4 S ⋅ cm-1 on the same order as polymer electrolyte. The realization of genuine Mg2+ storage and fast diffusion kinetics enabled a rare high-power Mg-intercalation battery with inorganic oxides. The success of this work provides important information on engineering surface and interlayer chemistries of layered materials to tackle the sluggish intercalation kinetics of multivalent ions.

10.
Adv Sci (Weinh) ; 8(12): 2100220, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34194947

RESUMO

The configurational entropy is an emerging descriptor in the functional materials genome. In thermoelectric materials, the configurational entropy helps tune the delicate trade-off between carrier mobility and lattice thermal conductivity, as well as the structural phase transition, if any. Taking GeTe as an example, low-entropy GeTe generally have high carrier mobility and distinguished zT > 2, but the rhombohedral-cubic phase transition restricts the applications. In contrast, despite cubic structure and ultralow lattice thermal conductivity, the degraded carrier mobility leads to a low zT in high-entropy GeTe. Herein, medium-entropy alloying is implemented to suppress the phase transition and achieve the cubic GeTe with ultralow lattice thermal conductivity yet decent carrier mobility. In addition, co-alloying of (Mn, Pb, Sb, Cd) facilitates multivalence bands convergence and band flattening, thereby yielding good Seebeck coefficients and compensating for decreased carrier mobility. For the first time, a state-of-the-art zT of 2.1 at 873 K and average zT ave of 1.3 between 300 and 873 K are attained in cubic phased Ge0.63Mn0.15Pb0.1Sb0.06Cd0.06Te. Moreover, a record-high Vickers hardness of 270 is attained. These results not only promote GeTe materials for practical applications, but also present a breakthrough in the burgeoning field of entropy engineering.

11.
ACS Omega ; 6(4): 3252-3258, 2021 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-33553943

RESUMO

Combining the bond-order-length-strength (BOLS) and atomic bonding and electronic model (BB model) with density functional theory (DFT) calculations, we studied the atomic bonding and electronic binding energy behavior of Bi atoms adsorbed on the Li(110) surface. We found that the Bi atoms adsorbed on the Li(110) surface form two-dimensional (2D) geometric structures, including letter-, hexagon-, galaxy-, crown-, field-, and cobweb-shaped structures. Thus, we obtained the following quantitative information: (i) the field-shaped structure can be considered the bulk structure; (ii) the field-shaped structure of Bi atom formation has a 5d energy level of 22.727 eV, and in the letter shape structure, this energy is shifted to values greater than 0.342 eV; and (iii) the Bi/Li(110) heterojunction transfers charge from the inner Li atomic layer to the outermost Bi atomic layer. In addition, we analyzed the bonding and electronic dynamics involved in the formation of the Bi/Li(110) heterojunctions using residual density of states. This work provides a theoretical reference for the fine tuning of binding energies and chemical bonding at the interfaces of 2D metallic materials.

12.
Cell Stem Cell ; 27(4): 574-589.e8, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32810435

RESUMO

Hypoplastic left heart syndrome (HLHS) is a complex congenital heart disease characterized by abnormalities in the left ventricle, associated valves, and ascending aorta. Studies have shown intrinsic myocardial defects but do not sufficiently explain developmental defects in the endocardial-derived cardiac valve, septum, and vasculature. Here, we identify a developmentally impaired endocardial population in HLHS through single-cell RNA profiling of hiPSC-derived endocardium and human fetal heart tissue with an underdeveloped left ventricle. Intrinsic endocardial defects contribute to abnormal endothelial-to-mesenchymal transition, NOTCH signaling, and extracellular matrix organization, key factors in valve formation. Endocardial abnormalities cause reduced cardiomyocyte proliferation and maturation by disrupting fibronectin-integrin signaling, consistent with recently described de novo HLHS mutations associated with abnormal endocardial gene and fibronectin regulation. Together, these results reveal a critical role for endocardium in HLHS etiology and provide a rationale for considering endocardial function in regenerative strategies.


Assuntos
Síndrome do Coração Esquerdo Hipoplásico , Células-Tronco Pluripotentes Induzidas , Endocárdio , Humanos , Miocárdio , Transdução de Sinais
13.
Langmuir ; 35(50): 16407-16415, 2019 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-31750660

RESUMO

On Fe(100), CO molecules can get activated efficiently so that CO bond breaking occurs with its transition state in close connection to the adsorbate. The CO bonding thus serves as a prototype model, nicely representing a balance of two simultaneous processes, namely, bond making with the surface and bond breaking within the adsorbate. Such unique configuration highlighting the interplay of two fundamental processes in one adsorption geometry, about which chemists have often fantasized, provides a viable solution to understand the very fundamental aspects of chemistry exemplified in a broad range of disciplines. Using density functional theory calculations, in this paper, we get a glimpse into how the CO bond activation is gestated and initiated in the adsorbate, wherein orbital cooperation in CO activation is evidenced by external CO bond making with the metal and internal CO bond breaking. We find that the symmetry breaking of occupied molecular orbitals in both 5σ and 1π symmetries marks efficient CO bond activation, which is reinforced by 1π → 2π excitations and 2π backdonation that are coupled with the symmetry transition of partially occupied 2π orbitals to a rotational symmetry. Our findings promote our knowledge of CO bond activation beyond the established picture of 5σ donation and 2π backdonation without symmetry breaking and may have insightful implications on orbital control of molecular activation, with further possible impact on elucidating the physical basis of heterogeneous catalysis.

14.
Nat Commun ; 10(1): 4777, 2019 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-31664017

RESUMO

Early diagnosis and noninvasive detection of liver fibrosis and its heterogeneity remain as major unmet medical needs for stopping further disease progression toward severe clinical consequences. Here we report a collagen type I targeting protein-based contrast agent (ProCA32.collagen1) with strong collagen I affinity. ProCA32.collagen1 possesses high relaxivities per particle (r1 and r2) at both 1.4 and 7.0 T, which enables the robust detection of early-stage (Ishak stage 3 of 6) liver fibrosis and nonalcoholic steatohepatitis (Ishak stage 1 of 6 or 1 A Mild) in animal models via dual contrast modes. ProCA32.collagen1 also demonstrates vasculature changes associated with intrahepatic angiogenesis and portal hypertension during late-stage fibrosis, and heterogeneity via serial molecular imaging. ProCA32.collagen1 mitigates metal toxicity due to lower dosage and strong resistance to transmetallation and unprecedented metal selectivity for Gd3+ over physiological metal ions with strong translational potential in facilitating effective treatment to halt further chronic liver disease progression.


Assuntos
Meios de Contraste/química , Gadolínio/química , Hipertensão Portal/diagnóstico por imagem , Fígado/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Doença Crônica , Diagnóstico Precoce , Humanos
15.
J Colloid Interface Sci ; 554: 500-511, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31326783

RESUMO

Recently, bismuth oxyhalide photocatalysts have attracted much attention owing to their unique layered structure. In this paper, fluorine isomorphously substituted BiOBrxI1-x solid solution was synthesized by controlling the molar ratios of F, Br and I elements by the chemical precipitation method at room temperature. It was found that BiOF0.4Br0.5I0.1 exhibited excellent photocatalytic activity for the degradation of methyl orange, which was 10.1, 5.0 and 4.3 times higher than that of BiOI, BiOBr and BiOBr0.9I0.1 under visible light irradiation, respectively. It could be inferred that fluorine substitution is favorable to enhance the internal electric field (IEF) for BiOBrxI1-x with layered structure, which could improve the separation efficiency of the photogenerated holes and electrons and thus enhance the photocatalytic activity. On the other hand, the concentration of oxygen vacancies (OVs) rose with the increase of fluorine content, which could facilitate the adsorption of pollutants and serve as trapping sites for photo-induced carriers to improve the photocatalytic activity. The finding provides new insights into the synergistic effect of IEF and OVs toward the construction of high efficient photocatalysts.

16.
J Biol Chem ; 294(22): 8973-8990, 2019 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-31010828

RESUMO

Chronic, low-grade inflammation increases the risk for atherosclerosis, cancer, and autoimmunity in diseases such as obesity and diabetes. Levels of CD4+ T helper 17 (Th17) cells, which secrete interleukin 17A (IL-17A), are increased in obesity and contribute to the inflammatory milieu; however, the relationship between signaling events triggered by excess nutrient levels and IL-17A-mediated inflammation is unclear. Here, using cytokine, quantitative real-time PCR, immunoprecipitation, and ChIP assays, along with lipidomics and MS-based approaches, we show that increased levels of the nutrient-responsive, post-translational protein modification, O-GlcNAc, are present in naive CD4+ T cells from a diet-induced obesity murine model and that elevated O-GlcNAc levels increase IL-17A production. We also found that increased binding of the Th17 master transcription factor RAR-related orphan receptor γ t variant (RORγt) at the IL-17 gene promoter and enhancer, as well as significant alterations in the intracellular lipid microenvironment, elevates the production of ligands capable of increasing RORγt transcriptional activity. Importantly, the rate-limiting enzyme of fatty acid biosynthesis, acetyl-CoA carboxylase 1 (ACC1), is O-GlcNAcylated and necessary for production of these RORγt-activating ligands. Our results suggest that increased O-GlcNAcylation of cellular proteins may be a potential link between excess nutrient levels and pathological inflammation.


Assuntos
Ácidos Graxos/biossíntese , Interleucina-17/metabolismo , Células Th17/metabolismo , Acetil-CoA Carboxilase/metabolismo , Acilação/efeitos dos fármacos , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/metabolismo , Citocinas/metabolismo , Ácidos Graxos/análise , Feminino , Humanos , Interleucina-17/genética , Lipidômica/métodos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Obesidade/metabolismo , Obesidade/patologia , Regiões Promotoras Genéticas , Ligação Proteica , Piranos/farmacologia , Células Th17/citologia , Tiazóis/farmacologia , Ativação Transcricional/efeitos dos fármacos
17.
J Lipid Res ; 60(3): 539-549, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30670473

RESUMO

Sortilin 1 (Sort1) is a member of the Vps10p domain intracellular trafficking receptor family. Genetic variations of the SORT1 gene are strongly associated with plasma cholesterol levels in humans. Recent studies have linked Sort1 to regulation of cholesterol metabolism in hepatocytes and pro-inflammatory response in macrophages, but the tissue-specific roles of Sort1 in lipid metabolism have not been well defined. We developed Sort1 floxed mice and investigated the development of Western diet (WD)-induced steatosis, hepatic inflammatory response, and hyperlipidemia in hepatocyte Sort1 KO mice and myeloid cell Sort1 KO mice. Our findings suggest that hepatocyte Sort1 deficiency attenuated diet-induced hepatic steatosis and hypercholesterolemia in mice. In contrast, myeloid Sort1 deficiency did not reduce hepatic cytokine expression or plasma cholesterol levels, but exacerbated hepatic triglyceride accumulation in WD-fed mice. Finally, we showed that treating WD-fed mice with an orally bioavailable Sort1 inhibitor, AF38469, decreased plasma cholesterol and hepatic cytokine expression. AF38469 treatment did not affect diet-induced obesity or insulin resistance, but was associated with reduced hepatic VLDL secretion and higher hepatic cholesterol 7α-hydrolase expression in WD-fed mice. In conclusion, findings from this study suggest that Sort1 loss-of-function in hepatocytes contributes to lower plasma cholesterol, and pharmacological inhibition of Sort1 attenuates diet-induced hypercholesterolemia in mice.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular/antagonistas & inibidores , Proteínas Adaptadoras de Transporte Vesicular/genética , Colesterol/sangue , Dieta Ocidental/efeitos adversos , Técnicas de Inativação de Genes , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Proteínas Adaptadoras de Transporte Vesicular/deficiência , Animais , Glicemia/metabolismo , Citocinas/metabolismo , Jejum/sangue , Fígado Gorduroso/sangue , Fígado Gorduroso/genética , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/genética , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL
18.
RSC Adv ; 9(17): 9342-9347, 2019 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-35520743

RESUMO

The electronic structures of two-dimensional (2D) indium (In) and bismuth (Bi) metal on BN nanosheets are systematically studied using hybrid density functional theory (DFT). We found that 2D In and Bi metal effectively modulate the band gap of a BN nanosheet. We also found that the indirect band gap of the 2D In and Bi metal electronic structures are 0.70 and 0.09 eV, respectively. This modulation originates from the charge transfer between the 2D metal and BN nanosheet interfaces, as well as from the electron redistribution of the In/BN and Bi/BN heterojunctions of the s and p orbitals. Our results provide an insight into 2D In/BN and Bi/BN heterojunctions, which should be useful in the design of 2D In and Bi metal-semiconductor-based devices.

19.
JCI Insight ; 3(8)2018 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-29669937

RESUMO

Bile acids are signaling molecules that critically control hepatocellular function. Disrupted bile acid homeostasis may be implicated in the pathogenesis of chronic liver diseases. Glutathione is an important antioxidant that protects the liver against oxidative injury. Various forms of liver disease share the common characteristics of reduced cellular glutathione and elevated oxidative stress. This study reports a potentially novel physiological function of bile acids in regulating hepatic sulfur amino acid and glutathione metabolism. We found that bile acids strongly inhibited the cysteine dioxygenase type-1-mediated (CDO1-mediated) cysteine catabolic pathway via a farnesoid X receptor-dependent mechanism. Attenuating this bile acid repressive effect depleted the free cysteine pool and reduced the glutathione concentration in mouse liver. Upon acetaminophen challenge, cholestyramine-fed mice showed impaired hepatic glutathione regeneration capacity and markedly worsened liver injury, which was fully prevented by N-acetylcysteine administration. These effects were recapitulated in CDO1-overexpressing hepatocytes. Findings from this study support the importance of maintaining bile acid homeostasis under physiological and pathophysiological conditions, as altered hepatic bile acid signaling may negatively impact the antioxidant defense mechanism and sensitivity to oxidative injury. Furthermore, this finding provides a possible explanation for the reported mild hepatotoxicity associated with the clinical use of bile acid sequestrants in human patients.


Assuntos
Ácidos e Sais Biliares/metabolismo , Cisteína/metabolismo , Glutationa/metabolismo , Fígado/metabolismo , Estresse Oxidativo/fisiologia , Acetaminofen/administração & dosagem , Acetaminofen/efeitos adversos , Acetilcisteína/administração & dosagem , Acetilcisteína/uso terapêutico , Analgésicos não Narcóticos/efeitos adversos , Animais , Anticolesterolemiantes/efeitos adversos , Ácidos e Sais Biliares/efeitos adversos , Resina de Colestiramina/administração & dosagem , Resina de Colestiramina/efeitos adversos , Sequestradores de Radicais Livres/uso terapêutico , Glutationa/efeitos adversos , Hepatócitos/metabolismo , Homeostase/fisiologia , Fígado/lesões , Fígado/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL
20.
Toxicol Sci ; 161(1): 34-47, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-28453831

RESUMO

Sortilin 1 (Sort1) is an intracellular trafficking receptor that mediates protein sorting in the endocytic or secretory pathways. Recent studies revealed a role of Sort1 in the regulation of cholesterol and bile acid (BA) metabolism. This study further investigated the role of Sort1 in modulating BA detoxification and cholestatic liver injury in bile duct ligated mice. We found that Sort1 knockout (KO) mice had attenuated liver injury 24 h after bile duct ligation (BDL), which was mainly attributed to less bile infarct formation. Sham-operated Sort1 KO mice had about 20% larger BA pool size than sham-operated wildtype (WT) mice, but 24 h after BDL Sort1 KO mice had significantly attenuated hepatic BA accumulation and smaller BA pool size. After 14 days BDL, Sort1 KO mice showed significantly lower hepatic BA concentration and reduced expression of inflammatory and fibrotic marker genes, but similar degree of liver fibrosis compared with WT mice. Unbiased quantitative proteomics revealed that Sort1 KO mice had increased hepatic BA sulfotransferase 2A1, but unaltered phase-I BA metabolizing cytochrome P450s or phase-III BA efflux transporters. Consistently, Sort1 KO mice showed elevated plasma sulfated taurocholate after BDL. Finally, we found that liver Sort1 was repressed after BDL, which may be due to BA activation of farnesoid x receptor. In conclusion, we report a role of Sort1 in the regulation of hepatic BA detoxification and cholestatic liver injury in mice. The mechanisms underlying increased hepatic BA elimination in Sort1 KO mice after BDL require further investigation.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Ácidos e Sais Biliares/biossíntese , Colestase/metabolismo , Fígado/metabolismo , Proteínas Adaptadoras de Transporte Vesicular/genética , Animais , Ácidos e Sais Biliares/genética , Modelos Animais de Doenças , Ligadura , Masculino , Camundongos , Camundongos Knockout , Sulfotransferases/metabolismo
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