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1.
Front Immunol ; 11: 623, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32425926

RESUMO

Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer with a poor prognosis and limited therapeutic options. Alpha-fetoprotein (AFP), an established clinical biomarker of HCC, has been employed as an attractive target for T cell-based immunotherapy against this disease given its high expression in the tumor and restricted expression in normal tissues. We have identified a number of T cell receptors (TCRs) recognizing the HLA-A*02:01 restricted AFP158-166 peptide FMNKFIYEI, providing a TCR candidate pool for identifying TCRs with optimal clinical benefit. To select the ideal AFP TCR for clinical use, we evaluated the efficacy and safety profile of 7 TCRs by testing their potency toward AFP-expressing HCC cells and their specificity based upon reactivity to normal and transformed cells covering a wide variety of primary cell types and HLA serotypes. Furthermore, we assessed their cross-reactivity to potential protein candidates in the human genome by an extensive alanine scan (X-scan). We first selected three TCR candidates based on the in vitro anti-tumor activity. Next we eliminated two potential cross-reactive TCRs based on their reactivity against normal and transformed cells covering a variety of primary cell types and HLA serotypes, respectively. We then excluded the potential cross-reactivity of the selected TCR with a protein candidate identified by X-scan. At present we have selected an AFP TCR with the optimal affinity, function, and safety profile, bearing properties that are expected to allow AFP TCR redirected T cells to specifically differentiate between AFP levels on tumor and normal tissues. An early phase clinical trial using T cells transduced with this TCR to treat HCC patients (NCT03971747) has been initiated.

2.
Nutrients ; 12(4)2020 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-32344640

RESUMO

To address the problem of malnutrition in poor rural areas of China, this study aims to examine the effects of social-psychological factors in food consumption of rural residents in poor counties of Southwest China. In addition, it investigates the role of perceived need and habit within the theory of planned behavior (TPB) in predicting food consumption. A survey with random sampling was conducted on rural residents (n = 424), and the theoretical frameworks of both the standard and extended TPB were applied for comparison purposes. Structural equation modeling was applied to test the relationships among constructs. Consumption of five food items was studied, respectively: meat, eggs, dairy, fish, and fruits. Results showed that incorporation of perceived need and habit substantially increased the explanatory power of the TPB, but these factors only had significant direct effects on intention rather than behavior. Perceived need and habit are stronger predictors of intention than any other TPB construct for consumption of all food items except for meat. We found indirect effects of the constructs in the extended TPB model on consumption to be different across food items. Practical implications to improve consumption of different food items were proposed accordingly.

3.
Artigo em Inglês | MEDLINE | ID: mdl-32312759

RESUMO

BACKGROUND: Vitamin E is an essential micronutrient and critical human antioxidant previously tested for cancer preventative effects with conflicting clinical trial results that have yet to be explained biologically. METHODS: We examined baseline and on-trial serum samples for 154 men randomly assigned to receive 400 IU vitamin E (as alpha-tocopheryl acetate; ATA) or placebo daily in the Vitamin E Atherosclerosis Prevention Study (VEAPS), and for 100 men administered 50 IU ATA or placebo daily in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study (ATBC). Over 970 metabolites were identified using ultrahigh-performance LC/MS-MS. Linear regression models estimated the change in serum metabolites of men supplemented with vitamin E versus those receiving placebo in VEAPS as compared with ATBC. RESULTS: Serum alpha-carboxyethyl hydrochroman (CEHC) sulfate, alpha-tocopherol, and beta/gamma-tocopherol were significantly altered by ATA supplementation in both trials (all P values ≤5.1 × 10-5, the Bonferroni multiple comparisons corrected statistical threshold). Serum C22 lactone sulfate was significantly decreased in response to the high-dose vitamin E in VEAPS (ß = -0.70, P = 8.1 × 10-6), but not altered by the low dose in ATBC (ß = -0.17, P = 0.4). In addition, changes in androgenic steroid metabolites were strongly correlated with the vitamin E supplement-associated change in C22 lactone sulfate only in the VEAPS trial. CONCLUSIONS: We found evidence of a dose-dependent vitamin E supplementation effect on a novel C22 lactone sulfate compound that was correlated with several androgenic steroids. IMPACT: Our data add information on a differential hormonal response based on vitamin E dose that could have direct relevance to opposing prostate cancer incidence results from previous large controlled trials.

4.
FEBS Lett ; 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32227472

RESUMO

The nicotinamide adenine dinucleotide (NAD+ )/Sirtuin (SIRT) system is linked to metabolic adaptation. This study aimed to determine the temporal profile of metabolic responses of the liver to cold exposure and changes in the hepatic NAD+ /SIRT system. Eight-week-old male C57BL/6 mice were individually housed in conventional cages under cold exposure (4 °C) for up to 5 days. Cold exposure decreased the hepatic triglyceride level and cholesterol level in mice by 1.7- and 1.6-fold, respectively. Lipogenic gene expression was persistently reduced, while gluconeogenic gene expression was transiently increased. Hepatic NAD+ /SIRT metabolism was induced during the 'cold remodeling' phase (days 1-3) and correlated with decreasing lipogenic and increasing gluconeogenic gene expression, contributing to the maintenance of whole-body lipid and glucose homeostasis.

5.
Adv Mater ; : e1908293, 2020 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-32249530

RESUMO

Safe and high-energy-density rechargeable batteries are increasingly indispensable in the pursuit of a wireless and fossil-free society. Advancements in present battery technologies and the investigation of next-generation batteries highly depend on the ever-deepening fundamental understanding and the rational designs of working electrodes, electrolytes, and interfaces. However, accurately analyzing energy materials and interfaces is severely hindered by their intrinsic limitations of air and electron-beam sensitivity, which restrains the research of energy materials in a low-efficiency trial-and-error paradigm. The emergence of cryogenic electron microscopy (cryo-EM) has enabled the nondestructive characterization of air- and electron-beam sensitive energy materials in the microscale and nanoscale, and even at atomic resolutions, affording closer insights into the primary chemistry and physics of working batteries. Herein, the development of cryo-EM and the applications in detecting energy materials are reviewed and analyzed from its overwhelming advantages in disclosing the underlying mystery of energy materials. Critical sample preparation methods as the precondition for cryo-EM are compared, which strongly affect the characterization accuracy. Furthermore, new developments in the analysis of energy materials, especially bulk electrodes and interfaces in lithium metal batteries, are presented according to different functions of cryo-EM. Finally, future directions of cryo-EM for analyzing energy materials are prospected.

6.
Arterioscler Thromb Vasc Biol ; : ATVBAHA120314172, 2020 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-32268790

RESUMO

OBJECTIVE: A decrease in nitric oxide, leading to vascular smooth muscle cell proliferation, is a common pathological feature of vascular proliferative diseases. Nitric oxide synthesis by eNOS (endothelial nitric oxide synthase) is precisely regulated by protein kinases including AKT1. ENH (enigma homolog protein) is a scaffolding protein for multiple protein kinases, but whether it regulates eNOS activation and vascular remodeling remains unknown. Approach and Results: ENH was upregulated in injured mouse arteries and human atherosclerotic plaques and was associated with coronary artery disease. Neointima formation in carotid arteries, induced by ligation or wire injury, was greatly decreased in endothelium-specific ENH-knockout mice. Vascular ligation reduced AKT and eNOS phosphorylation and nitric oxide production in the endothelium of control but not ENH-knockout mice. ENH was found to interact with AKT1 and its phosphatase PHLPP2 (pleckstrin homology domain and leucine-rich repeat protein phosphatase 2). AKT and eNOS activation were prolonged in VEGF (vascular endothelial growth factor)-induced ENH- or PHLPP2-deficient endothelial cells. Inhibitors of either AKT or eNOS effectively restored ligation-induced neointima formation in ENH-knockout mice. Moreover, endothelium-specific PHLPP2-knockout mice displayed reduced ligation-induced neointima formation. Finally, PHLPP2 was increased in the endothelia of human atherosclerotic plaques and blood cells from patients with coronary artery disease. CONCLUSIONS: ENH forms a complex with AKT1 and its phosphatase PHLPP2 to negatively regulate AKT1 activation in the artery endothelium. AKT1 deactivation, a decrease in nitric oxide generation, and subsequent neointima formation induced by vascular injury are mediated by ENH and PHLPP2. ENH and PHLPP2 are thus new proatherosclerotic factors that could be therapeutically targeted.

7.
Neurologist ; 25(2): 28-32, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32132497

RESUMO

BACKGROUND: Intravenous thrombolysis is the only approved pharmacological treatment for acute ischemic stroke (AIS) patients, but the immediate response to thrombolysis varies by patient. OBJECTIVE: To investigate the factors associated with early neurological improvement (ENI) after the administration of intravenous recombinant tissue plasminogen activator (rt-PA) treatment to AIS patients within 4.5 hours of onset. METHODS: Demographics, onset to treatment time, risk factors, and clinical and laboratory data of 209 AIS patients undergoing intravenous rt-PA therapy at a Chinese hospital between January 2013 and August 2016 were retrospectively analyzed. The National Institutes of Health Stroke Scale (NIHSS) score was recorded before thrombolytic therapy, 24 hours after the treatment, and 7 days after the treatment to evaluate the recovery of neurological function. ENI was defined as a ≥4-point decrease in NIHSS score compared with baseline or a score of 0 or 1 at 24 hours and 7 days. A multivariate logistic regression analysis was performed to assess the outcomes. RESULTS: Of the 209 AIS patients treated by intravenous thrombolysis with rt-PA, low-density lipoprotein (LDL) levels were significantly lower (P<0.05) in patients with ENI. The multivariable analysis showed that non-atrial fibrillation (AF) was independently associated with ENI at 24 hours and 7 days after thrombolysis. An overall 40.3% non-AF patients had ENI 24 hours after thrombolysis (odds ratio=2.501, 95% confidence interval: 1.204-5.198; P=0.014), and 65.9% non-AF patients had ENI 7 days after thrombolysis (odds ratio=2.953, 95% confidence interval: 1.434-6.081; P=0.003). Onset to treatment time was an independent predictor (P<0.05) for ENI at 7 days after thrombolysis. The NIHSS score and diastolic blood pressure on admission were associated with symptomatic intracerebral hemorrhagic transformation. CONCLUSIONS: Non-AF was independently associated with ENI after intravenous thrombolysis in AIS patients, but non-AF was not associated with the occurrence of symptomatic intracerebral hemorrhage. Onset to treatment time was an independent predictor of ENI at 7 days after thrombolysis in AIS patients.

8.
Artigo em Inglês | MEDLINE | ID: mdl-32195564

RESUMO

This work proposes a dual-cross-linked gel solid electrolyte (SE), here defined as Zn-re-inforced sodium alginate-polyacrylamide SE (Zn-reinforced SA-PAM SE), in which Na+ and Zn2+ coexist. The SE shows a high conductivity of 19.74 mS cm-1. Compared to the pure PAM gel, the tensile strength and compressive strength of Zn-reinforced SA-PAM SE are significantly enhanced to be 674.28 kPa and 16.29 MPa, respectively, because of the strengthening mechanism of Zn2+ cross-linked SA. Based on such a robust electrolyte, a novel hybrid cell is developed by involving Na0.5FeFe(CN)6-carbon nanotube composites (PB@CNT) as the Na+ intercalation-type cathode and metallic Zn as the plating anode. The hybrid cell shows an extremely high stability for 10,000 cycles with a record little capacity loss of 0.0027% per cycle, as Zn-reinforced SA-PAM SE successfully inhibits free water molecules from occupying low-spinning metallic sites (Fe-C) in Na0.5FeFe(CN)6. Ex situ X-ray photoelectron spectroscopy reveals that the dissolution of Na0.5FeFe(CN)6 is highly reduced by 79.5%. It is further noted that the corrosion and dendrites at the Zn2+/Zn plating anode are greatly hindered for the robust electrolyte. This work gives a pathway for the development of new aqueous ion batteries.

9.
Artigo em Inglês | MEDLINE | ID: mdl-32203631

RESUMO

In situ evolution of electrocatalysts is of paramount importance in defining catalytic reactions. Catalysts for aprotic electrochemistry such as lithium-sulfur (Li-S) batteries are the cornerstone to enhance intrinsically sluggish reaction kinetics but the true active phases are often controversial. Herein, we reveal the electrochemical phase evolution of metal-based pre-catalysts (Co4 N) in working Li-S batteries that renders highly active electrocatalysts (CoSx ). Electrochemical cycling induces the transformation from single-crystalline Co4 N to polycrystalline CoSx that are rich in active sites. This transformation propels all-phase polysulfide-involving reactions. Consequently, Co4 N enables stable operation of high-rate (10 C, 16.7 mA cm-2 ) and electrolyte-starved (4.7 µL mgS -1 ) Li-S batteries. The general concept of electrochemically induced sulfurization is verified by thermodynamic energetics for most of low-valence metal compounds.

10.
Bioprocess Biosyst Eng ; 43(6): 1071-1079, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32036453

RESUMO

In this study, the immobilization technology was used to improve the LA yield and shorten the fermentation time. The optimum conditions to immobilize Lactobacillus pentosus ATCC 8041 cell were determined by Taguchi design L16 (45). The immobilized L. pentosus ATCC 8041 cells prepared by 2% sodium alginate (SA) and 6% polyvinyl alcohol (PVA) with the immobilization process by 0.10 M calcium chloride (CaCl2) and 2.5% boric acid (H3BO3) had the best performance of LA yield at the temperature of 35 °C, which is significantly higher than that of L. pentosus ATCC 8041 free cells. These cells maintained the stable and efficient performance in 15 repeated batch fermentation, and they also have excellent mechanical strength to keep from breakage caused by cell growth and agitation.

11.
J Natl Cancer Inst ; 112(2): 191-199, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31077299

RESUMO

BACKGROUND: Epidemiologic data are inconsistent regarding the vitamin E-lung cancer association, and no study to our knowledge has examined serologic changes in vitamin E status in relation to subsequent risk. METHODS: In a cohort of 22 781 male smokers in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study, we ascertained 3184 lung cancer cases during up to 28 years of observation. Cox proportional hazards models examined whether higher serum alpha-tocopherol concentrations at baseline, 3 years, or the interval change were associated with lower lung cancer risk. All statistical tests were two-sided. RESULTS: After adjustment for age, body mass index, smoking intensity and duration, serum total cholesterol, and trial intervention group, we found lower lung cancer risk in men with high baseline alpha-tocopherol (fifth quintile [Q5] vs Q1, hazard ratio [HR] = 0.76, 95% confidence interval [CI] = 0.66 to 0.87, Ptrend < .001). A similar reduction in risk was seen for serum alpha-tocopherol at 3 years (Q5 vs Q1, HR = 0.78, 95% CI = 0.67 to 0.91, Ptrend = .004). The inverse risk association appeared stronger for younger men and those who had smoked fewer years but was similar across trial intervention groups. We also found reduced risk among men not supplemented with vitamin E who had a lower serum alpha-tocopherol at baseline and greater increases in concentrations at 3 years (third tertile vs first tertile of serum alpha-tocopherol change, HR = 0.74, 95% CI = 0.59 to 0.91, P = .005). CONCLUSIONS: Higher vitamin E status, as measured by serum alpha-tocopherol concentration, as well as repletion of a low vitamin E state, was related to decreased lung cancer risk during a 28-year period. Our findings provide evidence supporting the importance of adequate physiological vitamin E status for lung cancer risk reduction.

12.
Angew Chem Int Ed Engl ; 59(8): 3252-3257, 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-31756011

RESUMO

High-energy-density Li metal batteries suffer from a short lifespan under practical conditions, such as limited lithium, high loading cathode, and lean electrolytes, owing to the absence of appropriate solid electrolyte interphase (SEI). Herein, a sustainable SEI was designed rationally by combining fluorinated co-solvents with sustained-release additives for practical challenges. The intrinsic uniformity of SEI and the constant supplements of building blocks of SEI jointly afford to sustainable SEI. Specific spatial distributions and abundant heterogeneous grain boundaries of LiF, LiNx Oy , and Li2 O effectively regulate uniformity of Li deposition. In a Li metal battery with an ultrathin Li anode (33 µm), a high-loading LiNi0.5 Co0.2 Mn0.3 O2 cathode (4.4 mAh cm-2 ), and lean electrolytes (6.1 g Ah-1 ), 83 % of initial capacity retains after 150 cycles. A pouch cell (3.5 Ah) demonstrated a specific energy of 340 Wh kg-1 for 60 cycles with lean electrolytes (2.3 g Ah-1 ).

13.
Heart Lung Circ ; 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31813744

RESUMO

BACKGROUND: Patients with atrial fibrillation are at increased risk of stroke and mortality. It is not clear if inflammatory biomarkers are associated with stroke and mortality in patients with atrial fibrillation. We aimed to evaluate the predictive value of three inflammatory biomarkers (interleukin [IL]-9, IL-10, and interferon [IFN]-γ) for stroke and mortality in atrial fibrillation. METHOD: A total of 232 patients with new-onset atrial fibrillation were enrolled and 217 patients were completely followed-up. Peripheral plasma concentrations of cytokines (IL-9, IL-10, and IFN-γ) were measured using Luminex xMAP assays. The association between dichotomous groups of cytokines and outcomes were evaluated by a Cox proportional hazards model. The incremental value of inflammatory biomarkers, in addition to the CHA2DS2-VASc score, was also assessed. RESULTS: Patients were followed-up for a median duration of 27 (interquartile range [IQR], 23-30) months. The elevated plasma level of IFN-γ was an independent risk factor for stroke (hazard ratio [HR], 4.02 [IQR, 1.06-15.34]; p=0.042) and all-cause mortality (HR, 3.93 [IQR, 1.43-10.78]; p=0.008) in patients with atrial fibrillation. Adding high IFN-γ to the CHA2DS2-VASc score showed improvement in discrimination and reclassification prediction for stroke and mortality. However, IL-9 and IL-10 had no statistically significant association with stroke and all-cause mortality in patients with atrial fibrillation. CONCLUSIONS: In this "real-world" cohort of patients with atrial fibrillation, we have shown for the first time that plasma levels of IFN-γ could provide incremental prognostic value supplementary to that obtained from the CHA2DS2-VASc scores for predicting of stroke and all-cause mortality.

14.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 44(10): 1099-1106, 2019 Oct 28.
Artigo em Chinês | MEDLINE | ID: mdl-31857502

RESUMO

OBJECTIVE: To characterize the timeliness of ß3 adrenergic receptor agonist CL316,243-induced browning of white adipose tissues in mice.
 Methods: Male C57BL/6J mice at 10 weeks of age were housed in conventional cages and given sterile saline for the control group or CL316,243 (1 µg/g) for the experimental group via intraperitoneal injection for 1, 3, and 5 days. Food intake and body weight were measured daily. Interscapular brown adipose tissue (iBAT), inguinal subcutaneous white adipose (sWAT) and epididymal white adipose tissue (eWAT) were harvested for histological and gene expression analysis.
 Results: Compared with the control group, intraperitoneal injection of CL316,243 reduced the weight of eWAT on the first day. Meanwhile, CL316,243 continuously promoted the mRNA and protein expression of uncoupling protein-1 (UCP-1) in sWAT and eWAT. Furthermore, CL316,243 injection significantly decreased the food intake and weight gain of the mice, and reduced the diameter of adipocyte and accumulation of small lipid droplets in adipose tissues.
 Conclusion: CL316,243 can induce the brown-like remodeling in adipose tissues of mice in vivo, which show different time-dependent manners in different adipose tissues.


Assuntos
Tecido Adiposo Branco , Tecido Adiposo Marrom , Agonistas Adrenérgicos beta , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteína Desacopladora 1
15.
Haematologica ; 2019 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-31879325

RESUMO

Elucidating the regulation mechanism of integrin αIIbß3 is key to understand platelet biology and thrombotic diseases. Previous in vitro studies have implicated a role of migfilin in the support of platelet αIIbß3 activation, however, contribution of migfilin to thrombosis and hemostasis in vivo and a detailed mechanism of migfilin in platelets are not known. In this study, with migfilin deletion (migfilin-/-) mice, we report that migfilin is a pivotal positive regulator of hemostasis and thrombosis. Migfilin-/- mice showed a nearly doubled tail-bleeding time and a prolonged occlusion time in Fecl3-induced mesenteric arteriolar thrombosis. Migfilin deficiency impedes platelet thrombi formation on collagen surface and impairs platelet aggregation and dense-granule secretion. Supported by characteristic functional readings and phosphorylation status of distinctive signaling molecules in the bidirectional signaling processes of αIIbß3, the functional defects of migfilin-/- platelets appear to be mechanistically associated with a compromised outside-in signaling, rather than inside-out signaling. A synthesized cell-permeable migfilin peptide harboring filamin A binding sequence rescued the defective function and phosphorylation of signaling molecules of migfilin-/- platelets. Finally, migfilin does not influence the binding of filamin A and ß3 subunit of αIIbß3 in resting platelets, but hampers the re-association of filamin A and ß3 during the conduct of outside-in signaling, suggesting that migfilin functions through regulating the interaction dynamics of αIIbß3 and filamin A in platelets. Our study enhances the current understanding of platelet integrin αIIbß3-mediated outside-in signaling and proves that migfilin is an important regulator for platelet activation, hemostasis and thrombosis.

16.
Blood ; 134(Supplement_1): 50, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31723983

RESUMO

DISCLOSURES: Yao: Cellular Biomedicine Group Inc: Employment, Equity Ownership. Zhu:Cellular Biomedicine Group Inc: Employment, Equity Ownership. Huang:Cellular Biomedicine Group Inc: Employment, Equity Ownership. Zhu:Cellular Biomedicine Group Inc: Employment, Equity Ownership. Wei:Cellular Biomedicine Group Inc: Employment, Equity Ownership. Lan:Cellular Biomedicine Group Inc: Employment, Equity Ownership. LV:Cellular Biomedicine Group Inc: Employment, Equity Ownership. Wu:Cellular Biomedicine Group Inc: Employment, Equity Ownership. Wang:Cellular Biomedicine Group Inc: Employment, Equity Ownership. Yang:Cellular Biomedicine Group Inc: Employment, Equity Ownership. Zheng:Cellular Biomedicine Group Inc: Employment, Equity Ownership. Zhao:Cellular Biomedicine Group Inc: Employment, Equity Ownership. Zhang:Cellular Biomedicine Group Inc: Employment, Equity Ownership. Chen:Cellular Biomedicine Group Inc: Employment, Equity Ownership. Li:Cellular Biomedicine Group Inc: Employment, Equity Ownership. Ren:Cellular Biomedicine Group Inc: Employment, Equity Ownership. Zhang:Cellular Biomedicine Group Inc: Employment, Equity Ownership. Humphries:Cellular Biomedicine Group Inc: Employment, Equity Ownership. Yao:Cellular Biomedicine Group Inc: Employment, Equity Ownership.

17.
Artigo em Inglês | MEDLINE | ID: mdl-31746521

RESUMO

Lithium-sulfur (Li-S) batteries are highly regarded as the next-generation energy storage devices because of their ultrahigh theoretical energy density of 2600 Wh kg -1 . Sulfurized polyacrylonitrile (SPAN) is considered as a promising sulfur cathode to substitute conventional carbon/sulfur (C/S) composite to afford higher Columbic efficiency, improved cycling stability, and potential high-energy-density Li-SPAN batteries which attract growing attentions. However, unstable Li metal anode critically threatens the actual performances of Li-SPAN batteries with limited lifespan and safety hazards . Considering Li metal can react with almost all kinds of electrolyte to generate a protective solid electrolyt e interphase ( SEI ), electrolyte r egulation is widely accepted as a vital and feasible strategy to protect Li metal anode in rechargeable batteries . In this review, basic principles and current challenges of Li-SPAN batteries are firstly addressed. Recent advances on electrolyte regulation towards stable Li metal anode in Li-SPAN batteries are summarized to afford design strategies of solvents, lithium salts, additives, and gel electrolyte. Finally, prospects for future electrolyte design and Li anode protection in Li-SPAN batteries are also discussed.

18.
J Mol Cell Cardiol ; 137: 71-81, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31634485

RESUMO

Mutations in the PTPN11 gene, which encodes the protein tyrosine phosphatase Shp2, cause Noonan syndrome and LEOPARD syndrome, inherited multifaceted diseases including cardiac and vascular defects. However, the function of Shp2 in blood vessels, especially in vascular smooth muscle cells (VSMCs), remains largely unknown. We generated mice in which Shp2 was specifically deleted in VSMCs and embryonic cardiomyocytes using the SM22α-Cre transgenic mouse line. Conditional Shp2 knockout resulted in massive hemorrhage, cardiovascular defects and embryonic lethality at the late embryonic developmental stage (embryonic date 16.5). The thinning of artery walls in Shp2-knockout embryos was due to decreased VSMC number and reduced extracellular matrix deposition. Myocyte proliferation was decreased in Shp2-knockout arteries and hearts. Importantly, cardiomyocyte-specific Shp2-knockout did not cause similar vascular defects. Shp2 was required for TGFß1-induced expression of ECM components, including collagens in VSMCs. In addition, collagens were sufficient to promote Shp2-inefficient VSMC proliferation. Finally, Shp2 was deleted in adult mouse VSMCs by using SMMHC-CreERT2 and tamoxifen induction. Shp2 deletion dramatically inhibited the expression of ECM components, proliferation of VSMCs and neointima formation in a carotid artery ligation model. Therefore, Shp2 is required for myocyte proliferation in cardiovascular development and vascular remodeling through TGFß1-regulated collagen synthesis.

19.
Artigo em Inglês | MEDLINE | ID: mdl-31490599

RESUMO

The development of energy storage devices has received increasing attentions as a vital transformative technology to realize low-carbon economy and sustainable energy supply. Lithium-sulfur (Li-S) batteries are considered to be one of the most promising next-generation energy storage devices due to their ultrahigh energy density. Despite the extraordinary progress in the last few years, the actual energy density of Li-S batteries is still far from satisfactory to meet the demand for practical applications. Considering the sulfur electrochemistry highly dependent on solid-liquid-solid multi-phase conversion, the electrolyte amount plays a primary role to the practical performances of Li-S cells. Therefore, lean electrolyte volume with low electrolyte/sulfur ratio is essential for practical Li-S batteries to demonstrate their advantages in energy density, yet under which conditions is highly challenging to achieve acceptable electrochemical performances regarding sulfur kinetics, discharge capacity, Coulombic efficiency, and cycling stability especially for high-sulfur-loading cathodes. In this review, the impact of the electrolyte/sulfur ratio on the actual energy density and the economic cost of Li-S batteries is firstly addressed. Challenges and recent progresses of lean-electrolyte Li-S batteries are included according to the sulfur electrochemical processes regarding the dissolution-precipitation conversion and the solid-solid multi-phasic transition. Finally, prospects of future lean-electrolyte Li-S battery design and engineering are discussed.

20.
Adv Mater ; 31(43): e1903813, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31497898

RESUMO

Lithium-sulfur (Li-S) batteries hold great promise to serve as next-generation energy storage devices. However, the practical performances of Li-S batteries are severely limited by the sulfur cathode regarding its low conductivity, huge volume change, and the polysulfide shuttle effect. The first two issues have been well addressed by introducing mesoporous carbon hosts to the sulfur cathode. Unfortunately, the nonpolar nature of carbon materials renders poor affinity to polar polysulfides, leaving the shuttling issue unaddressed. In this contribution, atomic cobalt is implanted within the skeleton of mesoporous carbon via a supramolecular self-templating strategy, which simultaneously improves the interaction with polysulfides and maintains the mesoporous structure. Moreover, the atomic cobalt dopants serve as active sites to improve the kinetics of the sulfur redox reactions. With the atomic-cobalt-decorated mesoporous carbon host, a high capacity of 1130 mAh gS -1 at 0.5 C and a high stability with a retention of 74.1% after 300 cycles are realized. Implanting atomic metal in mesoporous carbon demonstrates a feasible strategy to endow nanomaterials with targeted functions for Li-S batteries and broad applications.

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