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2.
Int J Drug Policy ; 78: 102714, 2020 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-32135398

RESUMO

BACKGROUND: Hepatitis C virus (HCV) treatment uptake among people who inject drugs (PWID), a population with disproportionately high rates of HCV, remains low. Peers have been shown to positively impact a broad range of health outcomes for PWID. There is, however, limited data on the impact of PWID social network members on HCV treatment. METHODS: HCV-infected PWID enrolled in an ongoing community-based cohort were recruited as "indexes" to complete an egocentric social network survey. The survey elicited from the index PWID a list of their network members and the index's perception of network member characteristics. Logistic regression analyses were conducted to compare individual and network factors associated with HCV treatment in the index PWID. RESULTS: Among 540 HCV-infected PWID, the mean age was 55.7 years and the majority were black (87.2%) and male (69.8%). PWID reported a mean of 4.4 (standard deviation [SD] 3.2) network members, most of whom were relatives (mean 2.2 [SD 1.5]). In multivariable analysis, increasing index age and HIV infection were positively associated with HCV treatment, while drug use and homelessness in the preceding 6 months were negatively associated with HCV treatment. From a network perspective, having at least one network member who regularly talked with the index about seeing their doctor for HIV care was associated with HCV treatment (Adjusted Odds Ratio [AOR] 2.7; 95% Confidence Interval (CI) [1.3, 5.6]). Conversely, PWID who had at least one network member who helped them understand their HCV care were less likely to have been HCV treated (AOR 0.2; CI [0.1, 0.6). CONCLUSION: HCV treatment uptake in this group of PWID appeared to be positively influenced by discussions with network members living with HIV who were in care and negatively influenced by HCV information sharing within PWID networks. These findings underscore the influence of peers on health seeking behaviors of their network members and emphasizes the importance of well-informed peers.

3.
J Agric Food Chem ; 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-32208625

RESUMO

Tyrosol is a pharmacologically active phenolic compound widely used in the pharmaceutical and chemical industries. Microbial fermentation has potential value as an environmentally friendly approach to tyrosol production but suffers from low tyrosol yields and the need for expensive media additives. In this study, Escherichia coli MG1655 was modified by integrating an E. coli codon-optimized version of the Saccharomyces cerevisiae phenylpyruvate decarboxylase gene, named ARO10*, into the lacI locus. The resulting strain (YMGA*) produced 0.14 mM tyrosol from 2% glucose without the need for expensive media supplements. Subsequent deletion of E. coli genes designed to eliminate competing metabolic pathways (feaB, pheA, tyrB) or undesirable gene regulation (tyrR) produced a strain (YMGA*R) that produced 3.11 mM tyrosol. Tyrosol production was then increased to 10.92 mM by increasing the ARO10* copy number to five copies (strain YMG5A*R). Finally, tyrosol production was increased to 28 mM (ca. 3.9 g/L) by optimizing fermentation conditions in a 5-L fermenter. Engineering a productive E. coli strain with high tyrosol titer from glucose using a medium that does not require added amino acids, inducer, or antibiotic, which provides a solid basis to produce tyrosol through microbial fermentation.

4.
Ultrasonics ; 103: 106104, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32062180

RESUMO

The accurate estimation of time of flight (TOF) of an ultrasonic signal is essential in ultrasonic non-destructive testing (NDT). A novel method for TOF estimation based on the short-time Fourier transform (STFT) is proposed in this paper. Firstly, the time and frequency components of ultrasonic echoes are represented by a STFT. Then, the STFT spectrum of the echoes is projected onto the time domain. Finally, the TOF is estimated by calculating the location of the maximum modulus of STFT spectrum of the signal. A nonlinear Least Squares (LS) estimation method based on Modified Gauss-Newton (MGN) is employed to improve the estimation accuracy. The TOFs of multi-component echo signals are estimated by successive windowing. Numerical simulations and experiment tests show the performance of the proposed method.

5.
Biochem Biophys Res Commun ; 524(3): 575-581, 2020 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-32019675

RESUMO

Inhibiting the production of reactive oxygen species (ROS) in alveolar epithelial cells (AECs) under oxidative distress becomes a new therapeutic strategy for acute respiratory distress syndrome (ARDS). Herein in the present study, we investigated effects of Nox2, the catalytic subunit of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase type 2, on LPS-induced epithelium injury in ARDS mice and in human alveolar epithelial A549 cells. Severe lung injury, disruption of alveolar-capillary barrier with the loss of zonula occluden (ZO)-1 and up-regulated expression of Nox2 in AECs were exhibited in ARDS mice. In vitro, LPS induced decreased cell viability coupled with activated Nox2, high level of ROS, and destroyed ZO-1 distribution. Moreover, VAS2870 proved to inhibit Nox2 expression, reduce ROS generation, restore epithelium barrier integrity, and preserve cell viability in LPS-induced A549 cells. These data demonstrate that Nox2/ROS/ZO-1 axis is of great importance in AECs damage induced by LPS, and the utilization of VAS2870 to inhibit this pathway might lighten LPS-induced ARDS.

6.
Prep Biochem Biotechnol ; : 1-7, 2020 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-32069137

RESUMO

Stemonae Radix, a medicinal and edible herb, has been reported to possess various pharmacological effects. In the present study, Stemonae Radix was fermented by fungi to improve the antioxidant and anti-tyrosinase activities. The results showed that Stemonae Radix fermented by Mucor circinelloides T2-12 exhibited two-folds more antioxidant and anti-tyrosinase activities than non-fermented material. The increased activity might be ascribed to the improvement of total phenolic content, hydrolyzation of glucosides and esters of phenolics and metabolism of saccharides according to ultraviolet and nuclear paramagnetic resonance spectroscopy. This paper suggested that fermenting Stemonae Radix with M. circinelloides T2-12 is effective to increase antioxidant and anti-tyrosinase effects and Stemonae Radix fermented by M. circinelloides T2-12 might be newly alternative of natural antioxidant and tyrosinase inhibitor. The present study is the first to report that pure strain fermentation processing is effective in improving the antioxidant and anti-tyrosinase activities of Stemonae Radix.

7.
Cancer ; 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-32022262

RESUMO

BACKGROUND: Controversies exist regarding the biopsy technique of choice for the accurate diagnosis of soft-tissue sarcoma (STS). The objective of this systematic review and meta-analysis was to compare the diagnostic accuracy of core needle biopsy (CNB) versus incisional biopsy (IB) in STS with reference to the final histopathological result. METHODS: Studies regarding the diagnostic accuracy of CNB and IB in detecting STS were searched systematically in the MEDLINE and EMBASE databases. Estimates of sensitivity and specificity with associated 95% CIs for diagnostic accuracy were calculated. The risk of bias was assessed using the Quality Assessment of Diagnostic Accuracy Studies version 2 (QUADAS-2). RESULTS: A total of 17 studies comprising 2680 patients who underwent 1582 CNBs and 241 IBs with subsequent tumor resection met the inclusion criteria. The sensitivity and specificity of CNB and IB to detect the dignity of lesions were 97% (95% CI, 95%-98%) and 99% (95% CI, 97%-99%), respectively, and 96% (95% CI, 92%-99%) and 100% (95% CI, 94%-100%), respectively. Estimates of the sensitivity and specificity of CNB and IB to detect the STS histotype were 88% (95% CI, 86%-90%) and 77% (95% CI, 72%-81%), respectively, and 93% (95% CI, 87%-97%) and 65% (95% CI, 49%-78%), respectively. Patients who underwent CNB had a significantly reduced risk of complications compared with patients who underwent IB (risk ratio, 0.14; 95% CI, 0.03-0.56 [P ≤ .01). Quality assessment of studies revealed a high risk of bias. CONCLUSIONS: CNB has high accuracy in diagnosing the dignity of lesions and STS histotype in patients with suspected STS with fewer complications compared with IB. Therefore, CNB should be regarded as the primary biopsy technique.

8.
Planta Med ; 86(3): 205-211, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31918446

RESUMO

Three phenylpropanoid glucosides (1:  - 3: ) and one iridoid glucoside (11: ), together with eleven known glucosides, were isolated from the ethanol extract of the whole plant of Hemiphragma heterophyllum. Their structures were elucidated by means of 1D and 2D NMR spectroscopy, HRMS, and chemical methods. All compounds except 11: and 13:  - 15: showed varying degrees of α-glucosidase inhibitory activity. Compounds 5, 9: , and 12: were marginally active in the bioassay, while compounds 1:  - 4: , 6:  - 8: , and 10: exhibited appreciable inhibitory activity with an IC50 value of 33.6 ~ 83.1 µM, which was much lower than that of the positive control acarbose (IC50 = 310.8 µM).


Assuntos
Glucosídeos Iridoides , alfa-Glucosidases , Glucosídeos , Inibidores de Glicosídeo Hidrolases , Iridoides , Estrutura Molecular , Extratos Vegetais
9.
J Neurotrauma ; 37(3): 555-563, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31456470

RESUMO

Complications in upper and lower urinary function arise after spinal cord injury (SCI), which creates a significant impact on quality of life for those affected. One upper urinary complication is SCI-induced polyuria, or the overproduction of urine, of which the underlying mechanisms have yet to be elucidated. Activity-based training (ABT) has been utilized in both animal and clinical settings as a rehabilitative therapy to improve many issues that arise after SCI, including more recently urogenital function. The goal of the current study was to identify potential mechanisms contributing to previously identified improvements in polyuria with ABT, using a male rat moderate-severe spinal contusion model. Although ABT had no significant effect on reversing injury-induced alterations of serum arginine vasopressin and urinary atrial natriuretic peptide levels, there was a dramatic effect upon the receptors of these fluid balance hormones (vasopressin receptor 2 and natriuretic peptide A receptor), as well as kidney aquaporin 2 and sodium channels. ABT changes in densities of key receptors and kidney membrane proteins involved in fluid balance after chronic SCI support the likelihood of multiple mechanisms through which exercise can positively influence urinary tract function after SCI. By understanding the mechanisms, amount, and timing regarding how ABT improves different aspects of urinary function, more targeted training strategies can be developed to optimize the functional gains within the SCI population.

10.
Spectrochim Acta A Mol Biomol Spectrosc ; 225: 117482, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31472424

RESUMO

Cysteine has a great effect on the physiological and pathological processes, which could bring out various diseases such as skin lesions, edema, hair depigmentation, Alzheimer's, Parkinson's, and liver damage due to the abnormal concentrations of cysteine. Therefore, it is of great impoatance to develop a method for imaging Cys. Herein, a novel fluorescent probe was developed for imaging Cys in vivo specially. This turn-on probe exhibited favorable advantages including large Stokes shift (90 nm), fast response (10 min), good selectivity, low cytotoxicity and so on. Furthermore, the probe could be applied to monitoring cysteine in living HeLa cells, which indicates that this turn-on probe could penetrate viable cell membranes and image Cys over other analystes especially HCy and GSH.

11.
AIDS Care ; 32(2): 238-241, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31146549

RESUMO

Pre-exposure prophylaxis (PrEP) could have a substantial impact on the HIV epidemic within the US. However, the implementation of PrEP interventions outside of clinical trials has been slow and faces considerable barriers. The aim of the current study was to qualitatively explore PrEP-related patient-reported outcomes (PRO) among MSM patients who enrolled in a PrEP program at two public STD clinics in Baltimore. We conducted in-depth interviews with 18 PrEP patients who self-identified as MSM at two Baltimore City Health Department STD clinics between March and November, 2017. A codebook was developed using an iterative process. During analysis, the study team identified various biomedical and psychosocial PrEP-related PRO among MSM PrEP patients. In addition to HIV prevention, PrEP-related PRO included greater peace of mind, better continuity in care and awareness about health and well-being, relationship solidarity with serodiscordant partners, and access to social services. These findings on PrEP-related PRO can potentially contribute to improving patient-provider communication, leading to increased engagement in care and uptake of PrEP by MSM.

12.
Behav Brain Res ; 379: 112319, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-31669346

RESUMO

Chronic cerebral hypoperfusion is an important risk factor for vascular dementia (VaD) and other brain dysfunctions, for which there are currently no effective medications available. In the present study, we investigated the potential therapeutic effects of cornel iridoid glycoside (CIG) on VaD in rats modeled by permanent bilateral common carotid artery ligation (2-vessel occlusion, 2VO). The object recognition test (ORT) and Morris water maze (MWM) test were conducted to evaluate the learning and memory function. Western blot analysis and immunohistochemical staining were used to detect the expression of related proteins. Results showed that intragastric administration of CIG (30, 60, and 120 mg/kg) for 3 months significantly increased the discrimination index in ORT and decreased the escape latency in MWM test, ameliorating the learning and memory deficit in 2VO rats. Further data indicated that CIG increased the expression of neurotrophic factors (NGF and BDNF) and their receptors (TrkA and TrkB), glutamate receptor subunits (NMDAR1 and GluR2) in the cerebral cortex and hippocampus of 2VO rats. In addition, CIG elevated the expression of PI3K subunits p110α and p85, further upregulated the phosphorylation of Akt, GSK3ß-ser9 and CREB in the cerebral cortex and hippocampus at 3 months after 2VO surgery. Collectively, CIG treatment improved learning and memory deficit induced by chronic cerebral hypoperfusion via increasing neurotrophic factors thus protecting glutamate receptors and activating PI3K/Akt/GSK3ß/CREB signaling pathway in rats. These results suggest that CIG may be beneficial to VaD therapy.

13.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 27(6): 1820-1824, 2019 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-31839044

RESUMO

OBJECTIVE: To explore the efficacy and safety of allogeneic hematopoietic stem cell transplantation (allo-HSCT) in the treatment of relapsed or refractory peripheral T-cell lymphoma(PTCL). METHODS: The clinical data of 6 patients with relapsed or refractory PTCL undergoing allo-HSCT from Sep. 2014 to Sep. 2018 in the department of hematology, aerospace center hospital were retrospectively analyzed. Complications and disease-free survival after HSCT were observed. RESULTS: All the patients could well tolerate the conditioning regimen and acquired hematopoietic recon-struction. Following up till December 2018, with a median time of 11.5 months (1-51); acute GVHD developed in 2 cases and chronic GVHD developed in 5 cases, Among 6 cases one case died of viral pheumonia and the other 5 patients remained disease-free survival. The longest disease-free survival time has reached 51 months. CONCLUSION: allo-HSCT is a safe and effective method for relapsed or refractory peripheral T-cell lymphoma, which can be chosen as salvage treatment method for patients with primary resistance. Optimization of the conditioning regimen may result in better efficacy of allo-HSCT.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda , DNA (Citosina-5-)-Metiltransferases , Humanos , Mutação , Estudos Retrospectivos , Condicionamento Pré-Transplante , Tirosina Quinase 3 Semelhante a fms
14.
Ann Transplant ; 24: 594-604, 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31712547

RESUMO

BACKGROUND Tacrolimus is a widely used immunosuppressant in renal transplant recipients. It was demonstrated in rats and healthy volunteers that Wuzhi capsules could inhibit metabolism and maintain blood concentration of tacrolimus. However, there are no clinical studies of Wuzhi capsules in renal transplant recipients. This research aimed to assess the effect of Wuzhi capsules on the blood concentration of tacrolimus in renal transplant recipients. MATERIAL AND METHODS A total of 158 Chinese renal transplant recipients receiving tacrolimus with or without Wuzhi capsules were included in this retrospective study. The cohort study included 126 recipients, with 86 recipients receiving Wuzhi capsules (WZCs) and the other 40 recipients not receiving WZCs. Another 32 recipients were involved in a self-control study. RESULTS Dose- and body weight-adjusted trough concentrations (C0/D/W) of tacrolimus in the WZC group were found to be significantly higher than that in the non-WZC group (P<0.05). The improvement of C0/D/W by administration of Wuzhi capsules was more significant in CYP3A5 expressers than in non-expressers following subgroup analysis. Furthermore, the WZC group had a remarkably higher proportion of subjects who reached target tacrolimus concentration than in the non-WZC group, both in CYP3A5 expressers (P=0.01) and non-expressers (P<0.001). Multiple linear regression analysis and self-control analysis confirmed the positive impact of Wuzhi capsules on tacrolimus concentration (P<0.001). CONCLUSIONS Wuzhi capsules can increase tacrolimus trough concentration without adverse effects on allograft function, especially in CYP3A5 expressers. Efficient and convenient immunosuppressive effects on renal transplant recipients can be achieved by treatment including administration of Wuzhi capsules.

15.
Front Pharmacol ; 10: 1150, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31636563

RESUMO

Ca2+ entry via the transient receptor potential vanilloid 4 (TRPV4) channel contributes to Ca2+ overload and triggers many pathophysiological conditions, including myocardial ischemia/reperfusion (I/R) injury. Propofol, a widely used intravenous anesthetic, attenuates myocardial I/R injury. However, the mechanism of propofol remains to be examined. The present study aims to test the hypothesis that propofol attenuates myocardial I/R injury through the suppression of TRPV4. We used a murine ex vivo model of myocardial I/R and in vitro cultured myocytes subjected to hypoxia/reoxygenation (H/R). Propofol or TRPV4 antagonist, HC-067047, attenuates myocardial I/R injury in isolated hearts. In addition, propofol, HC-067047, or TRPV4-siRNA attenuates H/R-induced intracellular Ca2+ concentration ([Ca2+]i) increase and cell viability reduction. On the contrary, TRPV4 agonist GSK1016790A exacerbates both ex vivo and in vitro myocardial injury. Pretreatment with propofol reverses the myocardial injury and intracellular Ca2+ overload induced by GSK1016790A at least in vitro. However, neither the combination of propofol and HC-067047 nor applying propofol to cells transfected with TRPV4-siRNA creates additional protective effects. In addition, propofol dose-dependently inhibits TRPV4-mediated Ca2+ entry induced by GSK1016790A and 4α-PDD. Propofol attenuates myocardial I/R injury partially through the suppression of TRPV4 channel and the subsequent inhibition of intracellular Ca2+ overload.

16.
Fitoterapia ; 139: 104365, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31647954

RESUMO

As a folk medicine, Phlomis likiangensis is traditionally used in China to activate collaterals and protect cardiovascular system. We hypothesized that the beneficial effects of Phlomis likiangensis may be related to vasodilatation. In the present study, twelve known iridoid glucosides (1-12) were isolated from Phlomis likiangensis. The vasodilatory effects and the underlying mechanisms of the main components (iridoid glucosides) of Phlomis likiangensis on rat aortic rings were investigated. The result showed that iridoid glucosides significantly increased the vasodilatation in rat aortic rings, which was abolished by removing the endothelium of the vessels or by eliminating the generation of nitric oxide. Finally, the structure-activity relationship of compounds 1-12 was also speculated. Our findings provide the first evidence that the iridoid glucosides of Phlomis likiangensis may be the pharmacodynamic basis for its traditional efficacy.


Assuntos
Glucosídeos Iridoides/farmacologia , Phlomis/química , Vasodilatadores/farmacologia , Animais , Aorta/efeitos dos fármacos , Células Cultivadas , China , Células Endoteliais/efeitos dos fármacos , Técnicas In Vitro , Glucosídeos Iridoides/química , Masculino , Estrutura Molecular , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Plantas Medicinais/química , Ratos , Ratos Sprague-Dawley , Rizoma/química , Relação Estrutura-Atividade , Vasodilatação , Vasodilatadores/química
17.
Pharmacology ; : 1-7, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31618743

RESUMO

BACKGROUND: Transient receptor potential (TRP) channels are widely expressed in the mammals. However, the functions of canonical TRP (TRPC) in inflammatory responses are largely unknown. The present study was focused on the effect of canonical TRP5 (TRPC5) channel on the polarization of macrophage to an M1 phenotype. METHODS: Polarization of macrophages was studied in TRPC5 knockout (TRPC5-/-) mice and in Raw264.7, a mouse macrophage cell line. Indicators of M1 type polarized macrophage were measured in the aorta of mice. Inhibition of TRPC5 in macrophages was achieved by the administration of ML204 (a non-selective TRPC5 antagonist) or the silencing of the TRPC5 gene with short hairpin RNA. Lipopolysaccharide (LPS) was used to stimulate Raw264.7 cells to an M1 type polarization. Proinflammatory cytokines tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, and IL-6 were measured in mice or cells, and protein expressions of Akt, phosphorylated (p)-Akt, IκBα, p-IκBα, and NF-κB were analyzed in Raw264.7 cells. RESULTS: In TRPC5-/- mice the number of M1 type polarization of macrophages infiltrating into the aortic walls were significantly increased. The serum levels of inflammatory cytokines, TNF-α and IL-6 were also increased. Furthermore, after treated with ML204 or silenced the gene of TRPC5, the releases of TNF-α, IL-1ß and IL-6 from lipopolysaccharide-stimulated RAW264.7 cells were significantly increased. Meanwhile, phosphorylations of Akt and IκBα were upregulated, and the shift of NF-κB from the cytoplasm to nucleus was markedly enhanced. CONCLUSION: The activation of TRPC5 may inhibit the polarization of macrophage to an M1 phenotype by regulating Akt/IκB/NF-κB signaling pathways.

18.
Org Biomol Chem ; 17(42): 9280-9283, 2019 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-31633130

RESUMO

Herein, we report that iodine-catalyzed guanylation of primary amines can be accomplished with N,N'-di-Boc-thiourea and TBHP to afford the corresponding guanidines in 40-99% yields. Oxidation of the HI byproduct by TBHP eliminates the need for an extra base to prevent the protonation of substrates and makes the reaction especially useful for both electronically and sterically deactivated primary anilines.

19.
Int J Mol Sci ; 20(20)2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31627416

RESUMO

Obesity is associated with disrupted energy homeostasis and intestinal dysbiosis. Caulis Spatholobi, traditional Chinese medicine for herbal therapy, contains a wide range of bioactive compounds and has a specific pharmacological function. However, its effects on obesity and related metabolic disorder have remained largely unexplored. In this study, we showed that the water extract of Caulis Spatholobi (WECS) has a significant effect in inhibiting body weight gain, decreasing adiposity, maintaining glucose homeostasis, reducing insulin resistance and improving hepatic steatosis in diet-introduced obesity (DIO) mice. Besides, the administration of WECS significantly increased the expression levels of genes involved in the brown adipose tissue (BAT) activation and thermogenesis in DIO mice. Also, the activation of BAT treated with WECS was also confirmed in BAT primary cells. Mechanisms, the improvement of glucose homeostasis and insulin resistance may be related to the upregulated MAPK and AMPK pathways in white adipose tissue (WAT) and BAT. Notably, WECS also improved the obesity-induced gut microbiota dysbiosis, which induced an increase of anti-obesity and anti-diabetes related bacteria genus. In conclusion, Caulis Spatholobi can ameliorate obesity through activating brown adipose tissue and modulating the composition of gut microbiota. Our findings provide a novel perspective on Chinese medicine applications and provide a promising therapeutic approach for the treatment of obesity and metabolic disorders.

20.
Dalton Trans ; 48(37): 14156-14163, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31502611

RESUMO

A rational design of heterostructures for electrode materials is highly desired for boosting the electrochemical performance, but it is still challenging, especially through a cost-effective method. Herein, novel NiCo2O4 nanosheet-decorated leaf-like Co3O4 nanoarrays have been constructed on a Ni foam using a leaf-like Co-based metal-organic framework (Co-MOF-L) template, which can be simply prepared in an aqueous solution at room temperature. Combining the merits of MOF derivatives and the free-standing core-shell heterostructure, the leaf-like Co3O4@NiCo2O4 nanoarray electrode displayed a high specific capacity of 544.2 C g-1 at 1 A g-1, which is almost 9.3 times that of Co3O4 (58.3 C g-1) and 6 times that of NiCo2O4 (92.1 C g-1). It also displayed a good rate capacity (65.5% at 10 A g-1) and superior long-term stability (93.0% capacity retention over 5000 cycles at 10 A g-1). Moreover, a hybrid supercapacitor (HSC) assembled from the battery-type Co3O4@NiCo2O4 electrode and a capacitive activated carbon (AC) electrode delivered a high energy density of 36 W h kg-1 at a high power density of 852 W kg-1 with good cycling stability, demonstrating a capacity retention of 89.5% after 10 000 cycles at 10 A g-1. Furthermore, two connected HSCs could light up a red light-emitting diode (LED). Therefore, the as-fabricated leaf-like Co3O4@NiCo2O4 nanoarrays hold great promise as binder-free electrodes in electrochemical energy storage devices.

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