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1.
J Colloid Interface Sci ; 607(Pt 2): 1215-1225, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34571308

RESUMO

Developing effective electrocatalyst and fundamentally understanding the corresponding working mechanism are both urgently desired to overcome the current challenges facing lithium-oxygen batteries (LOBs). Herein, a series of NiFe-based bimetal-organic frameworks (NiFe-MOFs) with certain internal tensile strain are fabricated via a simple organic linker scission strategy, and served as cathode catalysts for LOBs. The introduced tensile strain broadens the inherent interatomic distances, leading to an upshifted d-band center of metallic sites and thus the enhancement of the adsorption strength of catalysts surface towards intermediates, which is contributed to rationally regulate the crystallinity of discharge product Li2O2. As a result, the uniformly distributed amorphous film-like Li2O2 tightly deposits on the surface of strain-regulated MOF, resulting in excellent electrochemical performance of LOBs, including a large discharge capacity of 12317.4 mAh g-1 at 100 mA g-1 and extended long-term cyclability of 357 cycles. This work presents a novel insight in adjusting the adsorption strength of cathode catalysts towards intermediates via introducing tensile strain in catalysts, which is a pragmatic strategy for improving the performance of LOBs.

2.
Food Chem ; 367: 130774, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34390913

RESUMO

Gas-liquid microextraction technique (GLME) has been integrated with dispersive solid phase extraction to establish a one-step sample pretreatment approach for rapid analysis of multi-class pesticides in different plant-derived foods. A 50 µL of organic solvent plus 40 mg of PSA were required throughout the 5-minute pretreatment procedure. Good trueness (recoveries of 67.2 - 105.4%) and precision (RSD ≤ 18.9%) were demonstrated by the one-step GLME method, with MLOQs ranged from 0.001 to 0.011 mg kg-1. As high as 93.6% pesticides experienced low matrix effect through this method, and the overall matrix effects (ME%) were generally better or comparable to QuEChERS. This method successfully quantified 2-phenylphenol, quintozene, bifenthrin and permethrin in the range of 0.001 - 0.008 mg kg-1 in real food samples. The multiresidue analysis feature of GLME has been validated, which displays further potential for on-site determination of organic pollutants in order to safeguard food safety and human health.


Assuntos
Resíduos de Praguicidas , Praguicidas , Humanos , Resíduos de Praguicidas/análise , Praguicidas/análise , Extração em Fase Sólida , Solventes
3.
Cancer Lett ; 524: 15-28, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34461182

RESUMO

Sunitinib is the first-line drug for treating renal cell carcinoma (RCC), and it functions mainly through inhibition of tumor angiogenesis. However, the patients may become insensitive or develop resistance toward sunitinib treatment, but the underlying mechanisms have not yet been fully elucidated. Herein, it was found that sunitinib could have adverse effects of promoting RCC progression by increasing vascular mimicry (VM) formation of RCC cells. Mechanism dissection revealed that sunitinib can increase the expression of a long non-coding RNA (lncRNA), lncRNA-ECVSR, thereby enhancing the stability of estrogen receptor ß (ERß) mRNA. Subsequently, the increased ERß expression can then function via transcriptional up-regulation of Hif2-α. Notably, sunitinib-increased lncRNA-ECVSR/ERß/Hif2-α signaling resulted in an increased cancer stem cell (CSC) phenotype, thereby promoting VM formation. Furthermore, the sunitinib/lncRNA-ECVSR-increased ERß expression can transcriptionally regulate lncRNA-ECVSR expression via a positive-feedback loop. Supportively, preclinical studies using RCC mouse xenografts demonstrated that combining sunitinib with the small molecule anti-estrogen PHTPP can increase sunitinib efficacy with reduced VM formation. Collectively, the findings of this study may aid in the development of potential biomarker(s) and novel therapies to better monitor and suppress RCC progression.

5.
Hepatology ; 2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34767673

RESUMO

BACKGROUND & AIMS: Hepatocellular carcinoma (HCC) is one of the main types of primary liver cancer with high morbidity and mortality, and poor treatment effect. Tripartite motif-containing protein 11 (TRIM11) has been shown to promote tumor formation in lung cancer, breast cancer, gastric cancer, and so on. However, the specific function and mechanism of TRIM11 in HCC have not been elucidated. APPROACH & RESULTS: Through clinical analysis, we found that the expression of TRIM11 was upregulated in HCC tissues and was associated with high tumor node metastasis (TNM) stages, advanced histological grade and poor patient survival. Then, by gain- and loss-of-function investigations, we demonstrated that TRIM11 promoted cell proliferation, migration, and invasion in vitro and tumor growth in vivo. Mechanistically, RNA sequencing and mass spectrometry analysis showed that TRIM11 interacted with PH domain leucine rich repeats protein phosphatase 1 (PHLPP1) and promoted K48-linked ubiquitination degradation of PHLPP1, thus promoted activation of protein kinase B (AKT) signaling pathway. Moreover, overexpression of PHLPP1 blocked the promotional effect of TRIM11 on HCC function. CONCLUSIONS: Our study confirmed that TRIM11 plays an oncogenic role in hepatocellular carcinoma through the PHLPP1/AKT signaling pathway, suggesting that targeting TRIM11 may be a promising target for the treatment of hepatocellular carcinoma.

6.
Neuron ; 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34793692

RESUMO

Social competition plays a pivotal role in determining individuals' social status. While the dorsomedial prefrontal cortex (dmPFC) is essential in regulating social competition, it remains unclear how information is processed within its local networks. Here, by applying optogenetic and chemogenetic manipulations in a dominance tube test, we reveal that, in accordance with pyramidal (PYR) neuron activation, excitation of the vasoactive intestinal polypeptide (VIP) or inhibition of the parvalbumin (PV) interneurons induces winning. The winning behavior is associated with sequential calcium activities initiated by VIP and followed by PYR and PV neurons. Using miniature two-photon microscopic (MTPM) and optrode recordings in awake mice, we show that VIP stimulation directly leads to a two-phased activity pattern of both PYR and PV neurons-rapid suppression followed by activation. The delayed activation of PV implies an embedded feedback tuning. This disinhibitory VIP-PV-PYR motif forms the core of a dmPFC microcircuit to control social competition.

7.
Front Immunol ; 12: 750046, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34804034

RESUMO

This study attempted to profile the tumor immune microenvironment (TIME) of non-small cell lung cancer (NSCLC) by multiplex immunofluorescence of 681 NSCLC cases. The number, density, and proportion of 26 types of immune cells in tumor nest and tumor stroma were evaluated, revealing some close interactions particularly between intrastromal neutrophils and intratumoral regulatory T cells (Treg) (r 2 = 0.439, P < 0.001), intrastromal CD4+CD38+ T cells and CD20-positive B cells (r 2 = 0.539, P < 0.001), and intratumoral CD8-positive T cells and M2 macrophages expressing PD-L1 (r 2 = 0.339, P < 0.001). Three immune subtypes correlated with distinct immune characteristics were identified using the unsupervised consensus clustering approach. The immune-activated subtype had the longest disease-free survival (DFS) and demonstrated the highest infiltration of CD4-positive T cells, CD8-positive T cells, and CD20-positive B cells. The immune-defected subtype was rich in cancer stem cells and macrophages, and these patients had the worst prognosis. The immune-exempted subtype had the highest levels of neutrophils and Tregs. Intratumoral CD68-positive macrophages, M1 macrophages, and intrastromal CD4+ cells, CD4+FOXP3- cells, CD8+ cells, and PD-L1+ cells were further found to be the most robust prognostic biomarkers for DFS, which were used to construct and validate the immune-related risk score for risk stratification (high vs. median vs. low) and the prediction of 5-year DFS rates (23.2% vs. 37.9% vs. 43.1%, P < 0.001). In conclusion, the intricate and intrinsic structure of TIME in NSCLC was demonstrated, showing potency in subtyping and prognostication.

9.
J Hematol Oncol ; 14(1): 188, 2021 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-34743750

RESUMO

BACKGROUND: Accumulating evidence shows that N6-methyladenine (m6A) modulators contribute to the etiology and progression of colorectal cancer (CRC). However, the exact mechanisms of m6A reader involved in glycolytic metabolism remain vague. This article aimed to crosstalk the m6A reader with glycolytic metabolism and reveal a new mechanism for the progression of CRC. METHODS: The relationship between candidate lncRNA and m6A reader was analyzed by bioinformatics, ISH and IHC assays. In vivo and in vitro studies (including MTT, CFA, trans-well, apoptosis, western blot, qRT-PCR and xenograft mouse models) were utilized to explore the biological functions of these indicators. Lactate detection, ATP activity detection and ECAR assays were used to verify the biological function of the downstream target. The bioinformatics, RNA stability, RIP experiments and RNA pull-down assays were used to explore the potential molecular mechanisms. RESULTS: We identified that the crosstalk of the m6A reader IMP2 with long-noncoding RNA (lncRNA) ZFAS1 in an m6A modulation-dependent manner, subsequently augmented the recruitment of Obg-like ATPase 1 (OLA1) and adenosine triphosphate (ATP) hydrolysis and glycolysis during CRC proliferation and progression. Specifically, IMP2 and ZFAS1 are significantly overexpressed with elevated m6A levels in CRC cells and paired CRC cohorts (n = 144). These indicators could be independent biomarkers for CRC prognostic prediction. Notably, IMP2 regulated ZFAS1 expression and enhanced CRC cell proliferation, colony formation, and apoptosis inhibition; thus, it was oncogenic. Mechanistically, ZFAS1 is modified at adenosine +843 within the RGGAC/RRACH element in an m6A-dependent manner. Thus, direct interaction between the KH3-4 domain of IMP2 and ZFAS1 where IMP2 serves as a reader for m6A-modified ZFAS1 and promotes the RNA stability of ZFAS1 is critical for CRC development. More importantly, stabilized ZFAS1 recognizes the OBG-type functional domain of OLA1, which facilitated the exposure of ATP-binding sites (NVGKST, 32-37), enhanced its protein activity, and ultimately accelerated ATP hydrolysis and the Warburg effect. CONCLUSIONS: Our findings reveal a new cancer-promoting mechanism, that is, the critical modulation network underlying m6A readers stabilizes lncRNAs, and they jointly promote mitochondrial energy metabolism in the pathogenesis of CRC.

10.
Orthop Surg ; 2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34747564

RESUMO

OBJECTIVE: To investigate the role of autologous platelet-rich plasma (PRP) on the repair of meniscal white-white zone injury through promoting the proliferation of canine bone marrow-derived mesenchymal stem cells (BMSCs). METHODS: A total of 24 beagle dogs were selected to construct meniscal white-white zone injury models in both lateral knee joints. All subjects were divided into four groups: control, BMSCs, PRP, and PRP + BMSCs. Immunohistochemistry was applied in the expression detection of type I and type II collagens. HE staining and methylene blue staining were performed to observe the injury of cartilage of lateral femoral condyle in each group. ELISA was used to detect the osteopontin (OPN) content in cartilage of lateral femoral condyle. HE staining and magnetic resonance imaging (MRI) were used to observe the healing of meniscus in each group. Outcome measures include the expression of OPN in the synovial fluid of knee joint, the expression of type I collagen and type II collagen, the healing of meniscus injury, and the damage degree of lateral femoral condyle cartilage. RESULTS: Compared with the control group, the expressions of type I and type II collagens were enhanced in the PRP group and the PRP + BMSCs group. Compared with 1 week before modeling, the expression of OPN was elevated in the control group and the BMSCs group at 3 weeks after modeling. There were no significant differences in the above indicators between the PRP group and the PRP + BMSCs group. According to MRI and pathological section after HE staining, meniscal healing in the PRP group and the PRP + BMSCs group was significantly improved as compared to that of the control group and the BMSCs group (all P < 0.05), and there was no significant difference between the PRP group and the PRP + BMSCs group (P > 0.05). All subjects were divided into the non-healing group and the healing group in accordance with the HE staining results in previous experiment. The injury of cartilage of lateral femoral condyle was significantly heavier in the non-healing group than that in the healing group. CONCLUSION: The application of PRP alone or in combination with BMSCs could promote the clinical healing rate of meniscal white-white zone injury.

11.
Anal Methods ; 13(45): 5478-5486, 2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34734943

RESUMO

Aldehydes are very common pollutants and many are possible human carcinogens. Herein, we report an easy-to-operate and low-cost method for discrimination of diverse aldehydes. Our colorimetric sensor array based on Tollens' reagent allows discrimination of ten kinds of aldehydes, showing a distinct color change from wine-red to deep yellow. In the presence of aldehydes, Ag shells are coated onto gold nanoparticles (GNPs) functionalized with diverse ligands (including bovine serum albumin, polyvinylpyrrolidone and L-cysteine), forming Au@Ag core-shell nanoparticles. The sensor array has great capacity for differentiating between ten kinds of aldehydes by color change, with accuracy and specificity of over 88%. Under optimal conditions, there is good linear correlation between Euclidean distance and formaldehyde concentrations ranging from 0.1 to 10 000 µM (R2 = 0.9908). The sensor was successfully used to determine formaldehyde content in shrimp, with recovery of 85.8% to 114.82%. Our GNPs sensor shows good potential for fast, reliable identification of aldehydes in food.

12.
Small ; : e2104112, 2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34816589

RESUMO

Foreign body reactions (FBR) to implants seriously impair tissue-implant integration and postoperative adhesion. The macrophage, owing to its phenotypic plasticity, is a major regulator in the formation of the inflammatory microenvironment; NF-κB signaling also plays a vital role in the process. It is hypothesized that NF-κB phosphorylation exerts a proinflammatory regulator in FBR to polylactide membranes (PLA-M) and adhesion. First, in vitro and in vivo experiments show that PLA-M induces NF-κB phosphorylation in macrophages, leading to M1 polarization and release of inflammatory factors. The inflammatory microenvironment formed due to PLA-M accelerates myofibroblast differentiation and release of collagen III and MMP2, jointly resulting in peritendinous adhesion. Therefore, JSH-23 (a selective NF-κB inhibitor)-loaded PLA membrane (JSH-23/PLA-M) is fabricated by blend electrospinning to regulate the associated M1 polarization for peritendinous anti-adhesion. JSH-23/PLA-M specifically inhibits NF-κB phosphorylation in macrophages and exhibits anti-inflammatory and anti-adhesion properties. The findings demonstrate that NF-κB phosphorylation has a critical role in PLA-induced M1 polarization and aggravating FBR to PLA-M. Additionally, JSH-23/PLA-M precisely targets modulation of NF-κB phosphorylation in FBR to break the vicious cycle in peritendinous adhesion therapy.

13.
Chem Commun (Camb) ; 57(94): 12687-12690, 2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34781327

RESUMO

Adverse dendritic growth destabilizes Li metal anodes (LMAs), dramatically limiting the commercial applications of Li metal batteries (LMBs). Herein, ZIF-67 with unsaturated coordinative metal sites is used to construct a protective coating to immobilize anions, which is capable of increasing the Li+ transference number (tLi+) to mitigate the electrolyte concentration gradient in the vicinity of LMAs. In addition, the ZIF-67-based layer provides highly ordered ionic diffusion pathways, thus enabling dendrite-free Li deposition. With a considerable Li+ transference number of 0.57, ZIF-67-Cu@Li symmetric cells deliver a superior long-term performance (over 1000 h), and Li-O2 full batteries with ZIF-67-Cu@Li electrodes display a high energy density of 1911.61 W h kg-1.

14.
Front Neurol ; 12: 747360, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34819910

RESUMO

Background: Late-onset multiple acyl-CoA dehydrogenase deficiency (LO-MADD) describes a curable autosomal recessive genetic disease caused by ETFDH mutations that result in defects in ETF-ubiquinone oxidoreductase. Almost all patients are responsive to riboflavin. This study describes the clinical presentations and genetic characteristics of five LO-MADD patients. Methods: From 2018 to 2021, we collected clinical and genetic data on five patients diagnosed with LO-MADD at our hospital and retrospectively analyzed their clinical characteristics, laboratory examination, electromyography, muscle biopsy, genetic analysis, and outcome data. Results: This study included three males and two females with mean onset age of 37.8 years. Fluctuating exercise intolerance was the most common presentation. Serum creatine kinase (CK) levels were significantly elevated in all patients, and plasma acylcarnitine profiles revealed an increase in long-chain acylcarnitine species in three cases. The urinary organic acid study revealed a high level of hydroxyglutaric acid in all patients. Electrophysiology demonstrated myogenic impairment. Muscle biopsies revealed lipid storage myopathy. Molecular analysis identified nine mutations (three novels and six reported) in ETFDH. Exercise intolerance and muscle weakness were dramatically improved in all patients treated with riboflavin (100 mg) daily following diagnosis. Conclusions: LO-MADD is caused by ETFDH variants and responds well to riboflavin. Three novel ETFDH pathogenic variants were identified, expanding their spectrum in the Chinese population and facilitating future interpretation and analysis of ETFDH mutations.

15.
Res Vet Sci ; 141: 156-163, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34749100

RESUMO

Duck hepatitis A virus type 1 (DHAV-1) infection is the main cause of duck viral hepatitis, but the replication process and distribution of DHAV-1 in vivo are still poorly understood. In this study, six-day-old ducklings were infected by two different methods: by intramuscular injection to establish DHAV-1 infection animal models and by the combined administration of virus solution orally, through nasal inhalation, through inoculation of the eye, and through intrarectal contact to simulate natural infection. Tissues were collected at different time points and quantitative real-time polymerase chain reaction (qPCR) was employed to analyze the gene expression levels of DHAV-1 in different tissues. The results showed that the viral gene levels responded to the different challenge methods. Viral gene expression levels in all tissues in the intramuscular injection group were lower than those in the group that simulated natural infection. In both groups, the liver was the primary tissue that responsible for the replication of DHAV-1 genes, as virus gene level peaked at 4 h post infection (hpi). In addition, the respiratory and digestive tracts were important regions for DHAV-1 infection as high viral gene levels were detected at early (8 hpi) and late (96 hpi) stages of infection. This research utilized a novel infection method to simulate natural infection and analyzed the DHAV-1 distribution in different tissues. The findings can provide guidance for making prevention and control measures.

16.
Quant Imaging Med Surg ; 11(10): 4389-4398, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34603993

RESUMO

Background: The precise pathogenesis of anophthalmia/microphthalmia remains unknown. Prenatal observation of the optic chiasm in fetuses with this malformation would assist in understanding the embryonic development of the condition. The present study aimed to establish the normal fetal size ranges of decussation of the optic chiasm, optic nerves, and optic tracts in the axial plane using two-dimensional transabdominal ultrasound throughout gestation and to compare these ranges to the corresponding values in fetuses with anophthalmia/microphthalmia. Methods: In total, 310 normal fetuses and 16 fetuses with anophthalmia/microphthalmia were included in this study. The widths of the decussation of the optic chiasm, optic nerves, and optic tracts of normal fetuses at 19-40 weeks' gestation were measured in the axial plane by two-dimensional transabdominal ultrasound. The same widths were retrospectively measured in the axial plane using three-dimensional ultrasound in fetuses with anophthalmia/microphthalmia and compared to the results from the normal fetuses. Results: The decussation, optic nerves, and optic tracts of 310 normal fetuses were measured. The normal widths of the decussation of the optic chiasm, optic nerves, and optic tracts increased linearly with gestational age. The interobserver and intraobserver reproducibility was excellent for the decussation but relatively low for the optic nerves and optic tracts. The optic nerve width of fetuses with anophthalmia/microphthalmia was significantly smaller than that of normal fetuses (P<0.001), but the widths of the decussation (P=0.061) and optic tracts (P=0.053) were not significantly different between the two groups. Conclusions: The normal ranges of the decussation of the optic chiasm, optic nerves, and optic tracts established in this study can provide a quantitative basis for prenatal evaluation of the optic pathway. Fetal anophthalmia/microphthalmia may be associated with optic nerve hypoplasia.

18.
Nat Neurosci ; 24(11): 1586-1600, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34663958

RESUMO

The basolateral amygdala (BLA) plays essential roles in behaviors motivated by stimuli with either positive or negative valence, but how it processes motivationally opposing information and participates in establishing valence-specific behaviors remains unclear. Here, by targeting Fezf2-expressing neurons in the BLA, we identify and characterize two functionally distinct classes in behaving mice, the negative-valence neurons and positive-valence neurons, which innately represent aversive and rewarding stimuli, respectively, and through learning acquire predictive responses that are essential for punishment avoidance or reward seeking. Notably, these two classes of neurons receive inputs from separate sets of sensory and limbic areas, and convey punishment and reward information through projections to the nucleus accumbens and olfactory tubercle, respectively, to drive negative and positive reinforcement. Thus, valence-specific BLA neurons are wired with distinctive input-output structures, forming a circuit framework that supports the roles of the BLA in encoding, learning and executing valence-specific motivated behaviors.


Assuntos
Tonsila do Cerebelo/metabolismo , Atenção/fisiologia , Aprendizagem da Esquiva/fisiologia , Corpo Estriado/metabolismo , Proteínas de Ligação a DNA/genética , Rede Nervosa/metabolismo , Proteínas do Tecido Nervoso/genética , Animais , Proteínas de Ligação a DNA/biossíntese , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Motivação/fisiologia , Proteínas do Tecido Nervoso/biossíntese
19.
Ecotoxicol Environ Saf ; 227: 112903, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34673417

RESUMO

As a new pollutant, microplastics have increasingly drawn public attention to its toxic behavior in the environment. The aim was to investigate the effect of styrene-butadiene-rubber microplastics (mSBR) with different degrees of aging on petroleum hydrocarbon (PHC) degrading bacteria in an environment with simultaneously existing pollutants. A series of experiments were carried out to investigate the changes in the physical and chemical properties of mSBR with aging and to examine the influence of these changes on the inhibition of PHC-degrading bacteria by mSBR in the vicinity of coexisting pollutants. The results showed that in the early stage of ultraviolet aging (10d), the particle surface shows wrinkles, but the structure is intact. After reaching the late stage of aging (20d), nano-scale fragments were generated on the surface of mSBR, the average particle size decreased from 3.074 µm to 2.297 µm, and the zeta potential increased from - 25.1 mV to - 33.1 mV. The inhibitory effect of bacteria is greater. At the same time, these changes in the physicochemical properties increase the adsorption effect of Cd by 20%, and also improve the stability of mSBR in solution, whereby bacterial growth is inhibited by inhibiting the LPO activity and protein concentration of PHC degrading bacteria.


Assuntos
Poluição por Petróleo , Petróleo , Poluentes Químicos da Água , Bactérias , Biodegradação Ambiental , Butadienos/toxicidade , Elastômeros , Hidrocarbonetos , Microplásticos , Petróleo/toxicidade , Plásticos/toxicidade , Estirenos , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
20.
Natl Sci Rev ; 8(7): nwaa204, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34691685

RESUMO

Hollow nanoparticles with large specific surface area and high atom utilization are promising catalysts for the hydrogen evolution reaction (HER). We describe herein the design and synthesis of a series of ultra-small hollow ternary alloy nanostructures using a simple one-pot strategy. The same technique was demonstrated for hollow PtNiCu nanoparticles, hollow PtCoCu nanoparticles and hollow CuNiCo nanoparticles. During synthesis, the displacement reaction and oxidative etching played important roles in the formation of hollow structures. Moreover, our hollow PtNiCu and PtCoCu nanoparticles were single crystalline, with an average diameter of 5 nm. Impressively, ultra-small hollow PtNiCu nanoparticles, containing only 10% Pt, exhibited greater electrocatalytic HER activity and stability than a commercial Pt/C catalyst. The overpotential of hollow PtNiCu nanoparticles at 10 mA cm-2 was 28 mV versus reversible hydrogen electrode (RHE). The mass activity was 4.54 A mgPt -1 at -70 mV versus RHE, which is 5.62-fold greater than that of a commercial Pt/C system (0.81 A mgPt -1). Through analyses of bonding and antibonding orbital filling, density functional theory calculations demonstrated that the bonding strength of different metals to the hydrogen intermediate (H*) was in the order of Pt > Co > Ni > Cu. The excellent HER performance of our hollow PtNiCu nanoparticles derives from moderately synergistic interactions between the three metals and H*. This work demonstrates a new strategy for the design of low-cost and high-activity HER catalysts.

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