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1.
Int J Nanomedicine ; 19: 9055-9070, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39246426

RESUMO

Purpose: The efficacy of systemic therapy for hepatocellular carcinoma (HCC) is limited mainly by the complex tumor defense mechanism and the severe toxic side-effects of drugs. The efficacy of apatinib (Apa), a key liver cancer treatment, is unsatisfactory due to inadequate targeting and is accompanied by notable side-effects. Leveraging nanomaterials to enhance its targeting represents a crucial strategy for improving the effectiveness of liver cancer therapy. Patients and Methods: A metal polyphenol network-coated apatinib-loaded metal-organic framework-based multifunctional drug-delivery system (MIL-100@Apa@MPN) was prepared by using metal-organic frameworks (MOFs) as carriers. The nanoparticles (NPs) were subsequently characterized using techniques such as X-ray diffraction (XRD), transmission electron microscopy (TEM), zeta potential measurements, and particle size analysis. In vitro experiments were conducted to observe the drug release kinetics and cytotoxic effects of MIL-100@Apa@MPN on HepG2 cells. The in vivo anti-tumor efficacy of MIL-100@Apa@MPN was evaluated using the H22 tumor-bearing mouse model. Results: The formulated MIL-100@Apa@MPN demonstrates remarkable thermal stability and possesses a uniform structure, with measured drug-loading (DL) and encapsulation efficiency (EE) rates of 28.33% and 85.01%, respectively. In vitro studies demonstrated that HepG2 cells efficiently uptake coumarin-6-loaded NPs, and a significant increase in cumulative drug release was observed under lower pH conditions (pH 5.0), leading to the release of approximately 73.72% of Apa. In HepG2 cells, MIL-100@Apa@MPN exhibited more significant antiproliferative activity compared to free Apa. In vivo, MIL-100@Apa@MPN significantly inhibited tumor growth, attenuated side-effects, and enhanced therapeutic effects in H22 tumor-bearing mice compared to other groups. Conclusion: We have successfully constructed a MOF delivery system with excellent safety, sustained-release capability, pH-targeting, and improved anti-tumor efficacy, highlighting its potential as a therapeutic approach for the treatment of HCC.


Assuntos
Antineoplásicos , Carcinoma Hepatocelular , Liberação Controlada de Fármacos , Ferroptose , Estruturas Metalorgânicas , Piridinas , Estruturas Metalorgânicas/química , Animais , Humanos , Piridinas/química , Piridinas/administração & dosagem , Piridinas/farmacocinética , Piridinas/farmacologia , Camundongos , Células Hep G2 , Concentração de Íons de Hidrogênio , Ferroptose/efeitos dos fármacos , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/farmacocinética , Antineoplásicos/administração & dosagem , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Sistemas de Liberação de Medicamentos/métodos , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Tamanho da Partícula , Nanopartículas/química
2.
Hum Reprod ; 39(2): 310-325, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38011909

RESUMO

STUDY QUESTION: What is the mechanism behind cryoinjury in human sperm, particularly concerning the interplay between reactive oxygen species (ROS) and autophagy, and how does it subsequently affect sperm fate? SUMMARY ANSWER: The freeze-thaw operation induces oxidative stress by generating abundant ROS, which impairs sperm motility and activates autophagy, ultimately guiding the sperm toward programmed cell death such as apoptosis and necrosis, as well as triggering premature capacitation. WHAT IS KNOWN ALREADY: Both ROS-induced oxidative stress and autophagy are thought to exert an influence on the quality of frozen-thawed sperm. STUDY DESIGN, SIZE, DURATION: Overall, 84 semen specimens were collected from young healthy fertile males, with careful quality evaluation. The specimens were split into three groups to investigate the ROS-induced cryoinjury: normal control without any treatment, sperm treated with 0.5 mM hydrogen peroxide (H2O2) for 1 h, and sperm thawed following cryopreservation. Samples from 48 individuals underwent computer-assisted human sperm analysis (CASA) to evaluate sperm quality in response to the treatments. Semen samples from three donors were analyzed for changes in the sperm proteome after H2O2 treatment, and another set of samples from three donors were analyzed for changes following the freeze-thaw process. The other 30 samples were used for fluorescence-staining and western blotting. PARTICIPANTS/MATERIALS, SETTING, METHODS: Sperm motility parameters, including progressive motility (PR %) and total motility (PR + NP %), were evaluated using the CASA system on a minimum of 200 spermatozoa. The proteomic profiles were determined with label-free mass spectrometry (MS/MS) and protein identification was performed via ion search against the NCBI human database. Subsequently, comprehensive bioinformatics was applied to detect significant proteomic changes and functional enrichment. Fluorescence-staining and western blot analyses were also conducted to confirm the proteomic changes on selected key proteins. The ROS level was measured using 2',7'-dichlorodihydrofluorescein diacetate labeling and the abundance of bioactive mitochondria was determined by evaluating the inner mitochondrial membrane potential (MMP) level. Molecular behaviors of sequestosome-1 (p62 or SQSTM1) and microtubule-associated proteins 1A/1B light chain 3 (LC3) were monitored to evaluate the state of apoptosis in human sperm. Fluorescent probes oxazole yellow (YO-PRO-1) and propidium iodide (PI) were utilized to monitor programmed cell death, namely apoptosis and necrosis. Additionally, gradient concentrations of antioxidant coenzyme Q10 (CoQ10) were introduced to suppress ROS impacts on sperm. MAIN RESULTS AND THE ROLE OF CHANCE: The CASA analysis revealed a significant decrease in sperm motility for both the H2O2-treatment and freeze-thaw groups. Fluorescence staining showed that high ROS levels were produced in the treated sperm and the MMPs were largely reduced. The introduction of CoQ10 at concentrations of 20 and 30 µM resulted in a significant rescue of progressive motility (P < 0.05). The result suggested that excessive ROS could be the major cause of sperm motility impairment, likely by damaging mitochondrial energy generation. Autophagy was significantly activated in sperm when they were under oxidative stress, as evidenced by the upregulation of p62 and the increased conversion of LC3 as well as the upregulation of several autophagy-related proteins, such as charged multivesicular body protein 2a, mitochondrial import receptor subunit TOM22 homolog, and WD repeat domain phosphoinositide-interacting protein 2. Additionally, fluorescent staining indicated the occurrence of apoptosis and necrosis in both H2O2-treated sperm and post-thaw sperm. The cell death process can be suppressed when CoQ10 is introduced, which consolidates the view that ROS could be the major contributor to sperm cryoinjury. The freeze-thaw process could also initiate sperm premature capacitation, demonstrated by the prominent increase in tyrosine phosphorylated proteins, verified with anti-phosphotyrosine antibody and immunofluorescence assays. The upregulation of capacitation-related proteins, such as hyaluronidase 3 and Folate receptor alpha, supported this finding. LARGE SCALE DATA: The data underlying this article are available in the article and its online supplementary material. LIMITATIONS, REASONS FOR CAUTION: The semen samples were obtained exclusively from young, healthy, and fertile males with progressive motility exceeding 60%, which might overemphasize the positive effects while possibly neglecting the negative impacts of cryoinjury. Additionally, the H2O2 treatment conditions in this study may not precisely mimic the oxidative stress experienced by sperm after thawing from cryopreservation, potentially resulting in the omission of certain molecular alterations. WIDER IMPLICATIONS OF THE FINDINGS: This study provides substantial proteomic data for a comprehensive and deeper understanding of the impact of cryopreservation on sperm quality. It will facilitate the design of optimal protocols for utilizing cryopreserved sperm to improve applications, such as ART, and help resolve various adverse situations caused by chemotherapy, radiotherapy, and surgery. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by grants from the Major Innovation Project of Research Institute of National Health Commission (#2022GJZD01-3) and the National Key R&D Program of China (#2018YFC1003600). All authors declare no competing interests. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Preservação do Sêmen , Sêmen , Masculino , Humanos , Espécies Reativas de Oxigênio/metabolismo , Sêmen/metabolismo , Motilidade dos Espermatozoides , Peróxido de Hidrogênio , Proteômica , Espectrometria de Massas em Tandem , Espermatozoides/metabolismo , Estresse Oxidativo , Criopreservação/métodos , Preservação do Sêmen/efeitos adversos , Preservação do Sêmen/métodos , Necrose/metabolismo
3.
Int J Biol Macromol ; 256(Pt 1): 128421, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38013085

RESUMO

A pH-responsive amphiphilic chitosan derivative, N-lauric-O-carboxymethyl chitosan (LA-CMCh), is synthesized. Its molecular structures are characterized by FTIR, 1H NMR, and XRD methods. The influencing factors are investigated, including the amount of lauric acid (LA), carboxymethyl chitosan (CMCh), N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride (EDC), and N-hydroxysuccinimide (NHS), and their molar ratio, reaction time, and reaction temperature on the substitution. The degrees of substitution (DS) of the lauric groups on the -NH2 groups are calculated based on the integrated data of 1H NMR spectra. The optimum reaction condition is obtained as a reaction time of 6 h, a reaction temperature of 80 °C, and a molar ratio of lauric acid to O-carboxymethyl chitosan to N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride to N-hydroxysuccinimide of 1:3:4.5:4.5, respectively. The crystallinity and initial decomposition temperature of LA-CMCh decrease, but the maximum decomposition temperature increases. The crystallinity is reduced due to the introduction of LA and the degree of hydrogen bonding among LA-CMCh molecules. LA-CMCh could self-aggregate into particles, which size and critical aggregation concentration depend on the degree of substitution and medium pH. LA-CMCh aggregates could load curcumin up to 21.70 %, and continuously release curcumin for >200 min. LA-CMCh shows nontoxicity to fibroblast HFF-1 cells and good antibacterial activity against S. aureus and E. coli, indicating that it could be used as an oil-soluble-drug carrier.


Assuntos
Carbodi-Imidas , Quitosana , Curcumina , Metilaminas , Succinimidas , Quitosana/química , Curcumina/farmacologia , Escherichia coli , Staphylococcus aureus , Concentração de Íons de Hidrogênio
4.
Regen Ther ; 24: 351-360, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37674692

RESUMO

Objective: Senile osteoporosis (SOP) is an aging-related disease. The depalmitoylating enzyme Acyl-protein thiesterase1 (APT1) is involved in disease regulation. This study explored the mechanism of APT1 in SOP. Methods: Eight-week-old SAMP6 mice were selected as SOP models and SAMR1 mice were controls, while osteoblasts were isolated from the femoral surface-soft tissues of SOP and control mice as in vitro models. Mouse femur morphological, bone mineral density (BMD), femur maximum elastic stress and maximum load, and APT1 expression were detected by HE staining, X-ray bone densitometer, material testing machine, and RT-qPCR and Western blot (WB). Osteoprotegrin (OPG)-labeled osteoblasts and APT1 localization in bone tissues were detected by immunohistochemical staining. APT1 expression was promoted in SOP mice by tail vein injection of APT1 lentivirus or promoted/silenced in osteoblasts by transfection of pcDNA3.1-APT1 overexpression or si-APT1 plasmids. SOP mouse osteoblast differentiation (OD), OD-related protein levels, osteoblast proliferation, BMPR1a palmitoylation level, and BMP/Smad pathway were detected by alizarin red staining, ALP activity detection, WB, CCK-8, and IP-ABE method. The effects of the pathway inhibitor LDN-193189 on OD were detected. Results: APT1 was under-expressed in osteoblasts of bone tissue in SOP mice and mainly localized in osteoblasts. SOP mice manifested increased bone marrow cavity and bone trabecular space, thinned trabecular bone, decreased BMD, maximum elastic stress, maximum load, and reduced OPG-positive osteoblasts in bone tissues, which were averted by APT1 overexpression, thus alleviating SOP. APT1 overexpression increased osteoblast calcium nodules, ALP activity, OD-related protein levels, and cell proliferation. In mechanism, APT1 overexpression inhibited BMPR1a palmitoylation in SOP mouse osteoblasts and activated the BMP/Smad pathway, thus promoting OD. Conclusion: APT1 activated the BMP/Smad pathway and promoted OD by regulating BMPR1a depalmitoylation, thus alleviating mouse SOP.

5.
Ticks Tick Borne Dis ; 14(6): 102238, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37722147

RESUMO

Infections with spotted fever group rickettsiae represent a worldwide health problem, characterized by persistent high fever, headache, and rash in humans, domestic animals, and wildlife. To date, the occurrence of Rickettsia species in hard ticks has not been thoroughly studied, especially in eastern and southern Kazakhstan. A total of 1,245 adult ticks, comprising 734 Dermacentor marginatus, 219 Hyalomma scupense, 144 Hyalomma asiaticum, 84 Hyalomma marginatum, 48 Rhipicephalus turanicus, and 16 Haemaphysalis erinacei, collected from East Kazakhstan, Abay, Jetsu, Almaty, Jambyl, South Kazakhstan and Qyzylorda oblasts of Kazakhstan, were used to screen rickettsial agents using molecular methods. Rickettsia raoultii, Rickettsia slovaca, Rickettsia aeschlimannii and Rickettsia heilongjiangensis were identified using sequencing, and 31.5% (392/1245) of ticks carried rickettsial agents. The difference in the natural landscapes explains the variety of the collected ticks and expands our knowledge of Rickettsia species and their geographical distribution in Kazakhstan. To the best of our knowledge, this study reports the first finding of R. heilongjiangensis in Kazakhstan.


Assuntos
Ixodidae , Rickettsia , Rickettsiose do Grupo da Febre Maculosa , Adulto , Animais , Humanos , Cazaquistão/epidemiologia , Rickettsiales
6.
Food Chem ; 407: 135144, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36493474

RESUMO

The rational design of high-efficiency catalysts for non-enzymatic glucose sensing is extremely important for the timely and effective monitoring of glucose content in beverages and human blood. A 3D bimetallic organic framework (Coordination Polymer of Oslo, CPO) nanorod array with oxygen vacancies was green fabricated on carbon cloth (Ni0.5Co0.5-CPO-27 NRA/CC) using dielectric barrier discharge (DBD) microplasma for the first time. Density functional theory (DFT) calculations demonstrated that the oxygen vacancy of Ni0.5Co0.5-CPO-27 can be effectively induced under DBD microplasma conditions. Based on the 3D nanorod arrays with rich oxygen vacancies and bimetallic synergistic effects, as a non-enzyme glucose sensor, the Ni0.5Co0.5-CPO-27 electrode exhibited a sensitivity of 8499.5 µA L/mmol cm-2 and 3239.2 µA L/mmol cm-2 and a limit of detection (LOD) of 0.16 µmol/L (S/N = 3). It has been successfully applied to the determination of glucose levels in real samples such as cola, green tea and human serum.


Assuntos
Técnicas Biossensoriais , Nanotubos , Humanos , Oxigênio , Glucose , Bebidas
7.
Curr Pharm Des ; 28(22): 1854-1862, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35585811

RESUMO

BACKGROUND: Docosahexaenoic acid-acylated phloridzin (PZ-DHA), a novel polyphenol fatty acid ester derivative, is synthesized through an acylation reaction of phloridzin (PZ) and docosahexaenoic acid (DHA). PZ-DHA is more stable than DHA and exhibits higher cellular uptake and bioavailability than PZ. OBJECTIVE: The study aims to investigate the effects of PZ-DHA on insulin resistance in the skeletal muscle and the related mechanisms; we used palmitic acid (PA)-treated C2C12 myotubes as an insulin resistance model. RESULTS: We found that PZ-DHA increased the activity of AMP-activated protein kinase (AMPK) and improved glucose uptake and mitochondrial function in an AMPK-dependent manner in untreated C2C12 myotubes. PZ-DHA treatment of the myotubes reversed PA-induced insulin resistance; this was indicated by increases in glucose uptake and the expression of membrane glucose transporter 4 (Glut4) and phosphorylated Akt. Moreover, PZ-DHA treatment reversed PA-induced inflammation and oxidative stress. These effects of PZ-DHA were mediated by AMPK. Furthermore, the increase in AMPK activity, improvement in insulin resistance, and decrease in inflammatory and oxidative responses after PZ-DHA treatment diminished upon co-treatment with a liver kinase B1 (LKB1) inhibitor, suggesting that PZ-DHA improved AMPK activity by regulating its upstream kinase, LKB1. CONCLUSION: The effects of PZ-DHA on insulin resistance in C2C12 myotubes may be mediated by the LKB1- AMPK signaling pathway. Hence, PZ-DHA is a promising therapeutic agent for insulin resistance in type 2 diabetes.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Proteínas Quinases Ativadas por AMP , Linhagem Celular , Ácidos Docosa-Hexaenoicos , Ésteres , Glucose , Humanos , Inflamação , Insulina , Fibras Musculares Esqueléticas , Ácido Palmítico , Florizina
8.
Polymers (Basel) ; 14(10)2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35631818

RESUMO

Chitosan has potential applications in many fields, due to its biocompatibility, biodegradability and reproducibility. However, the insolubility in water restricts its wide application. In order to expand the application of chitosan in the delivery of oil-soluble drugs and improve the efficacy of oil-soluble drugs, N-Glycidyltrimethyl ammonium chloride-modified chitosan (GTA-m-CS) and N,N-Dimethyl-N-dodecyl-N-(1,2-epoxy propyl) ammonium chloride (DDEAC), a kind of reactive surfactant, were synthesized and characterized by FTIR, NMR and XRD methods. The interactions between GTA-m-CS and DDEAC was studied by surface tension, viscosity, conductivity and fluorescence methods. The parameters, including equilibrium surface tension, critical micelle concentrations of DDEAC with different GTA-m-CS concentration, critical aggregation concentration of DDEAC, the amount of DDEAC adsorbed on GTA-m-CS, pc20 and πcmc were obtained from the surface tension curves. The influence of temperature on the above parameters were evaluated. The degree of counterion binding to micelle and the thermodynamic parameters of the system were calculated from the conductivity curves. According to the change of conductivity with temperature, the thermodynamic parameters of micellar formation were calculated. The aggregation number of DDEAC molecules in GTA-m-CS/DDEAC aggregates were calculated from steady-state fluorescence data. Based on the experimental results, the interaction models between GTA-m-CS and DDEAC were proposed. The GTA-m-CS/DDEAC aggregates could be used as curcumin carries, and achieved sustained release.

9.
Thromb Res ; 208: 26-34, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34688099

RESUMO

A pure recombinant staphylokinase-hirudin fusion protein (SFH) was obtained by recombinant genetic engineering and purification techniques. The thrombolytic and anticoagulant activities of SFH were investigated using in vitro coagulation models and chromogenic assays. The results showed that intact SFH had targeted thrombolytic activity, and gained anticoagulant activity when cleaved by FXa. In addition, we investigated the pharmacodynamics of SFH in vivo using a variety of animal models, including a rat inferior vena cava thrombosis model, a rat coronary thrombosis model, a rabbit carotid artery thrombosis model and a canine coronary thrombosis model. We found that SFH had an obvious thrombolytic effect and could prevent and reduce re-embolization after thrombolysis and reduce the serious bleeding side effects caused by the combination of thrombolytic and anticoagulant drugs. The results suggest that SFH can be used for thrombolytic therapy in thromboembolic diseases.


Assuntos
Fibrinolíticos , Hirudinas , Animais , Anticoagulantes , Cães , Fibrinolíticos/uso terapêutico , Metaloendopeptidases , Coelhos , Ratos , Proteínas Recombinantes de Fusão
10.
Ticks Tick Borne Dis ; 12(4): 101710, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33827036

RESUMO

Babesia species (Apicomplexa: Piroplasmorida) are tick-borne protozoan hemoparasites, which pose a significant threat to domestic animals, wildlife and humans. This study aimed to determine and characterize Babesia species in red foxes (Vulpes vulpes), Asian badgers (Meles leucurus) and their ticks. Blood, heart, liver, spleen, lung, kidney, large intestine and small intestine were collected from 19 wild carnivores (12 red foxes and 7 Asian badgers). All ticks were removed from these animals and identified according to morphological and molecular characteristics. The samples were tested for the presence of Babesia species using the 18S rRNA gene. Molecular analyses showed that the DNA of Babesia vogeli and Babesia vulpes was present in red fox organs/tissues and blood samples. A total of 54 hard ticks (38 Ixodes canisuga, 6 Haemaphysalis erinacei, 9 Ixodes kaiseri and 1 Dermacentor marginatus) were collected from red foxes and 12 (I. kaiseri) from Asian badgers. All ticks were adults. Among them, one I. kaiseri parasiting a red fox contained the DNA of B. vulpes while one I. canisuga was positive for Babesia sp. belonging to the clade "Babesia sensu stricto". Molecular and phylogenetic analyses indicated the presence of a novel genotype, Babesia sp. "badger China". Babesia sp. badger type A and type B from Asian badgers were different from those in European badgers. Co-infection with three Babesia genotypes was found in one Asian badger. This study provides the first data on Babesia infection in red foxes, Asian badgers and their ticks in China. Babesia vogeli was detected for the first time in red foxes in Asia. Co-infection and genetic diversity of Babesia genotypes in Asian badgers were also demonstrated.


Assuntos
Babesia/isolamento & purificação , Babesiose/epidemiologia , Raposas , Ixodidae/parasitologia , Mustelidae , Animais , Babesia/classificação , Babesiose/parasitologia , China/epidemiologia , Filogenia , Prevalência , RNA de Protozoário/análise , RNA Ribossômico 18S/análise
11.
Biomed Res Int ; 2015: 459170, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25861627

RESUMO

Thrombin and its membrane receptor, protease-activated receptor 1 (PAR1), have been reported to promote the development of lung cancer in vitro and in vivo. However, the intracellular molecular mechanism or signaling pathway that mediates the cytological effects after the thrombin-receptor interaction is poorly understood. Our previous study observed that the expression of phosphatase and tensin homolog deleted on chromosome 10 (PTEN) was downregulated in thrombin-stimulated lung cancer. In this study, the role of PTEN in thrombin-mediated cell function and the corresponding cell signaling pathway were studied in lung cancer cell Glc-82. The results indicated that thrombin downregulates the PTEN expression level and that PTEN plays an important role in thrombin-mediated Glc-82 functions, including cell cycle progression, cell apoptosis, and cell migration. The PI3K/AKT signaling pathway and its related proteins, including p27 and S phase kinase associated protein 2 (Skp2), are involved in the effects induced by PTEN downregulation. PAR1 plays a role in thrombin-mediated reduction of PTEN expression. This study suggested that the PTEN/PI3K/AKT signaling pathway plays an important role in thrombin/PAR1-mediated lung cancer cell growth and migration.


Assuntos
Neoplasias Pulmonares/genética , PTEN Fosfo-Hidrolase/genética , Trombina/metabolismo , Apoptose/genética , Ciclo Celular/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Regulação para Baixo/genética , Humanos , Neoplasias Pulmonares/metabolismo , Células MCF-7 , Fosfatidilinositol 3-Quinases/genética , Antígeno Nuclear de Célula em Proliferação/genética , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Quinases Associadas a Fase S/genética , Transdução de Sinais/genética
12.
J Nanosci Nanotechnol ; 12(2): 1040-3, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22629891

RESUMO

The influence of crystal grain dimension (approximately 38 nm and approximately 90 nm) on magnetic properties and magnetocaloric effects has been investigated for DyCuAl compound. The reduction of crystal grain dimension leads to the decrease of the Curie temperature (from 27 K to 24 K) and the evident enhancement of magnetic anisotropy. The peak values of magnetic entropy change under a field change of 0-5 T are 14.9 J kg(-1) K(-1) and 20.4 J kg(-1) K(-1) for DyCuAl compounds (approximately 38 nm and approximately 90 nm), respectively. A large refrigerant capacity is also produced in DyCuAl compounds (423 J kg(-1) and 379 J kg(-1) for the same field change, respectively). Large magnetic entropy changes and refrigerant capacities jointly make them attractive candidates for low-temperature magnetic refrigerant.

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