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1.
Molecules ; 28(17)2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37687110

RESUMO

Magnetic Functional Nanomaterials Co1-yZnyRExFe2-xO4 (RE (rare-earth) = La,Sm,Gd) were prepared using the sol-gel combustion method. XRD characterization confirms that the ferrite samples we synthesized are single-phase cubic structures. The variation in the average crystalline size and lattice parameter is related to RE ion doping. The Mössbauer spectra of CoRExFe2-xO4 are two sets of magnetic six-wire peaks that indicate the ferrimagnetic behavior of the sample. The calcination temperature greatly influences the absorption area of Mössbauer for CoFe2O4, indicating that the calcination temperature affects the iron ion content at the octahedral B and tetrahedral A sites. Additionally, scanning electron microscopy measurements of the substituted specimens reveal that the ferrite powders are nanoparticles. With an increase in RE ions, the coercivity increases, and the saturation magnetization changes obviously. The XRD characterization of Co0.7Zn0.3LaxFe2-xO4 shows that the main crystalline phase of the sample is the cubic spinel structure phase, and there are fewer secondary crystalline phases. The lattice parameter tends to decrease with the substitution of La3+ ions. The average grain size decreased significantly with the increase in La content. From ferrimagnetic state transition to relaxation behavior, the hyperfine magnetic field decreases in La concentration by room temperature Mössbauer spectra. With the substitution of La3+ ions, both the saturation magnetization and coercivity of the samples were reduced, and the coercivity of all samples was lower.

2.
Molecules ; 28(16)2023 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-37630362

RESUMO

CdxNi0.5-xCu0.2Zn0.3Fe2O4 (0 ≤ x ≤ 0.50) ferrite with a spinel structure was prepared using the sol-gel self-propagation method. The effects of Cd2+ doping on the structure, morphology, dielectric, and magnetic properties of Ni-Cu-Zn ferrite were examined using XRD, SEM, EDX, FTIR, MPMS, and dielectric tests. The cubic spinel structure was verified by XRD and FTIR analyses. The crystallite size and particle size information of the samples were obtained with XRD and SEM analysis. The sample particle size belonged to a class of nanoscale materials with a particle size range of 1-100 nm. The minor difference between the grain size and particle size indicated that the sample nanoparticles were composed of numerous microcrystals. The EDX spectra indicated that the samples contained all stoichiometric elements. MPMS was used to measure the hysteresis lines of the samples. According to the hysteresis line, the saturation magnetization intensity (Ms), coercivity (Hc), and magnetic moment (µB) of the sample increased and then decreased with the increase in cadmium concentration. The magnetization strength (Ms) is between 4-67 emu/g, and the coercivity (Hc) is between 9-46 Oe. The curves of the real part of the dielectric constant (ε'), the imaginary part of the dielectric constant (ε″), and the loss factor (tanδ) with frequency were measured in the frequency range 100 Hz-100 kHz by means of an impedance analyzer. The complex modulus spectrum was analyzed to understand the dynamics of the conduction process.

3.
Molecules ; 28(15)2023 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-37570715

RESUMO

Perovskite is the largest mineral on earth and has a variety of excellent physical and chemical properties. La1-xRxFeO3 (R = Co, Al, Nd, Sm) were synthesized using the sol-gel method and analyzed by XRD, TG-DTA, and VSM. With the increase in the Co2+ doping content, the diffraction peak drifted in the direction of a larger angle. The grain size of La1-xRxFeO3(R = Co) is mainly concentrated between 50.7 and 133.5 nm. As the concentration of Co2+ increased, the magnetic loop area and magnetization increased. La1-xRxFeO3(R = Al) is an orthorhombic perovskite structure, the grain size decreased with the increase in Al3+ doping concentration, and the minimum crystallite is 17.9 nm. The magnetic loop area and magnetization increased with the increase in Al3+ ion concentration. The enclosed area of the M-H curve of the sample decreased, and the ferromagnetic order gradually weakened and tended to be antiferromagnetic, which may be due to the increase in sintering temperature, decrease in the iron oxide composition, and changes in the magnetic properties. Proper doping can improve the magnetization of La1-xRxFeO3(R = Nd), refine the particles, and obtain better magnetic performance. As the Nd3+ ion concentration increased, the magnetic properties of the samples increased. Ms of La0.85Co0.15FeO3 prepared by different calcination time increases with the increase in calcination time. As the Sm3+ ion concentration increased, the magnetic properties of the samples increased. Proper doping can improve the magnetization of La1-xRxFeO3(R = Sm), refine the particles, and generate better magnetic performance.

4.
Molecules ; 28(10)2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37241966

RESUMO

AyB1-yCxFe2-xO4 (C=Ho,Gd,Al) ferrite powders have been synthesized by the sol-gel combustion route. The X-ray diffraction of the CoHoxFe2-xO4 (x = 0~0.08) results indicated the compositions of single-phase cubic ferrites. The saturation magnetisation of CoHoxFe2-xO4 decreased by the Ho3+ ions, and the coercivity increased initially and then decreased with the increase of the calcination temperature. The Mössbauer spectra indicated that CoHoxFe2-xO4 displays a ferrimagnetic behaviour with two normal split Zeeman sextets. The magnetic hyperfine field tends to decrease by Ho3+ substitution owing to the decrease of the A-B super-exchange by the paramagnetic rare earth Ho3+ ions. The value of the quadrupole shift was very small in the CoHoxFe2-xO4 specimens, indicating that the symmetry of the electric field around the nucleus is good in the cobalt ferrites. The absorption area of the Mössbauer spectra changed with increasing Ho3+ substitution, indicating that the substitution influences the fraction of iron ions at tetrahedral A and octahedral B sites. The X-ray diffraction of Mg0.5Zn0.5CxFe2-xO4(C=Gd,Al) results confirmed the compositions of single-phase cubic ferrites. The variation of the average crystalline size and lattice constant are related to the doping of gadolinium ions and aluminum ions. With increasing gadolinium ions and aluminum ions, the coercivity increased and the saturation magnetization underwent a significant change. The saturation magnetization of AlMg0.5Zn0.5FeO4 ferrite reached a minimum value (MS= 1.94 mu/g). The sample exhibited ferrimagnetic and paramagnetic character with the replacement with Gd3+ ions, that sample exhibited paramagnetic character with the replacement with Al3+ ions, and the isomer shift values indicated that iron is in the form of Fe3+ ions.

5.
Int J Biol Sci ; 18(5): 2060-2074, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35342361

RESUMO

Although cisplatin is the most effective first-line drug in the management of advanced non-small cell lung cancer (NSCLC), drug resistance remains a major clinical challenge. There is increasing evidence that icariside II (IS) exhibits antitumour activity in a variety of cancers. In the current study, we investigated the anticancer effects of icariside II combined with cisplatin and elucidated the underlying mechanism in NSCLC. Here, we showed that cotreatment with IS and cisplatin inhibited cell proliferation and induced cellular apoptosis. Using mRNA sequencing (mRNA-seq), we identified differentially expressed genes (DEGs) in which there was an enrichment in PERK-mediated unfolded protein response (UPR) signalling. The western blot results revealed that IS activated endoplasmic reticulum (ER) stress, including three branches of UPR signalling, PERK, IRE1 and ATF6, and the downstream PERK-eIF2α-ATF4-CHOP pathway, thus potentiating the apoptosis induced by cisplatin. In addition, the combination of IS with cisplatin significantly reduced xenograft tumour growth in C57BL/6 and BALB/c nude mice in vivo. Notably, the combination therapy displayed no evident toxicity. Taken together, IS enhances cisplatin-induced apoptosis partially by promoting ER stress signalling in NSCLC, suggesting that combination treatment with IS and cisplatin is a novel potential therapeutic strategy for NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Animais , Apoptose , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Linhagem Celular Tumoral , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Estresse do Retículo Endoplasmático , Flavonoides , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , RNA Mensageiro , eIF-2 Quinase/genética , eIF-2 Quinase/metabolismo
6.
Environ Health Perspect ; 130(2): 27002, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35108087

RESUMO

BACKGROUND: Severe environmental pollution and contaminants left in the environment due to the abuse of chemicals, such as methylmercury, are associated with an increasing number of embryonic disorders. Ultrasound imaging has been widely used to investigate embryonic development malformation and dysorganoplasia in both research and clinics. However, this technique is limited by its low contrast and lacking functional parameters such as the ability to measure blood oxygen saturation (SaO2) and hemoglobin content (HbT) in tissues, measures that could be early vital indicators for embryonic development abnormality. Herein, we proposed combining two highly complementary techniques into a photoacoustic-ultrasound (PA-US) dual-modality imaging approach to noninvasively detect early mouse embryo abnormalities caused by methylmercury chloride (MMC) in real time. OBJECTIVES: This study aimed to assess the use of PA-US dual-modality imaging for noninvasive detection of embryonic toxicity at different stages of growth following prenatal MMC exposure. Additionally, we compared the PA-US imagining results to traditional histological methods to determine whether this noninvasive method could detect early developmental defects in utero. METHODS: Different dosages of MMC were administrated to pregnant mice by gavage to establish models of different levels of embryonic malformation. Ultrasound, photoacoustic signal intensity (PSI), blood oxygen saturation (SaO2), and hemoglobin content (HbT) were quantified in all experimental groups. Furthermore, the embryos were sectioned and examined for pathological changes. RESULTS: Using PA-US imaging, we detected differences in PSI, SaO2, HbT, and heart volume at embryonic day (E)14.5 and E11.5 for low and high dosages of MMC, respectively. More important, our results showed that differences between control and treated embryos identified by in utero PA-US imaging were consistent with those identified in ex vivo embryos using histological methods. CONCLUSION: Our results suggest that noninvasive dual-modality PA-US is a promising strategy for detecting developmental toxicology in the uterus. Overall, this study presents a new approach for detecting embryonic toxicities, which could be crucial in clinics when diagnosing aberrant embryonic development. https://doi.org/10.1289/EHP8907.


Assuntos
Compostos de Metilmercúrio , Efeitos Tardios da Exposição Pré-Natal , Animais , Embrião de Mamíferos/diagnóstico por imagem , Feminino , Mamíferos , Compostos de Metilmercúrio/toxicidade , Camundongos , Gravidez , Ultrassonografia
7.
Cell Biochem Biophys ; 79(2): 231-238, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33125640

RESUMO

Skin fibrosis is one of the major features of scleroderma. WNT/ß-catenin signaling is associated with the progression of skin fibrosis. In this study, we aimed to determine the effect of icaritin (IT), a natural compound, on scleroderma-related skin fibrosis and its mechanisms. We found that IT could reduce the expression of COL1A1, COL1A2, COL3A1, CTGF, and α-SMA in human foreskin fibroblasts (HFF-1 cells), scleroderma skin fibroblasts (SSF cells), and TGF-ß-induced HFF-1 cells. Wnt/ß-catenin signaling was shown to be suppressed by IT. Additionally, IT activated AMPK signaling in HFF-1 cells. In conclusion, IT has an anti-skin fibrotic effect through activation of AMPK signaling and inhibition of WNT/ß-catenin signaling. Our findings indicate the potential role of IT in the treatment of scleroderma and provide novel insight for the selection of drug therapy for scleroderma.


Assuntos
Flavonoides/farmacologia , Escleroderma Sistêmico/patologia , Transdução de Sinais/efeitos dos fármacos , Proteínas Quinases Ativadas por AMP/metabolismo , Actinas/genética , Actinas/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Cadeia alfa 1 do Colágeno Tipo I , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Humanos , Escleroderma Sistêmico/metabolismo , Fator de Crescimento Transformador beta/farmacologia , Proteínas Wnt/metabolismo , beta Catenina/metabolismo
8.
Materials (Basel) ; 11(11)2018 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-30366443

RESUMO

Cobalt-chromium ferrite, CoCrxFe2-xO4 (x = 0⁻1.2), has been synthesized by the sol-gel auto-combustion method. X-ray diffraction (XRD) indicates that samples calcined at 800 °C for 3 h were a single-cubic phase. The lattice parameter decreased with increasing Cr concentration. Scanning electron microscopy (SEM) confirmed that the sample powders were nanoparticles. It was confirmed from the room temperature Mössbauer spectra that transition from the ferrimagnetic state to the superparamagnetic state occurred with the doping of chromium. Both the saturation magnetization and the coercivity decreased with the chromium doping. With a higher annealing temperature, the saturation magnetization increased and the coercivity increased initially and then decreased for CoCr0.2Fe1.8O4.

9.
Nanomaterials (Basel) ; 8(10)2018 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-30248902

RESUMO

A sol-gel autocombustion method was used to synthesize Al3+ ion-substituted cobalt ferrite CoAlxFe2-xO4 (x = 0⁻1.5). According to X-ray diffraction analysis (XRD), cobalt ferrite was in a single cubic phase after being calcined at 1000 °C for 3 h. Moreover, the lattice constant decreased with increase in aluminum substituents. When the sample was analyzed by Scanning Electron Microscopy (SEM), we found that uniformly sized, well-crystallized grains were distributed in the sample. Furthermore, we confirmed that Al3+ ion-substituted cobalt ferrite underwent a transition from ferrimagnetic to superparamagnetic behavior; the superparamagnetic behavior was completely correlated with the increase in Al3+ ion concentration at room temperature. All these findings were observed in Mössbauer spectra. For the cobalt ferrite CoAlxFe2-xO4, the coercivity and saturation magnetization decrease with an increase in aluminum content. When the annealing temperature of CoAl0.1Fe1.9O4 was steadily increased, the coercivity and saturation magnetization initially increased and then decreased.

10.
Materials (Basel) ; 11(10)2018 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-30248974

RESUMO

Zinc ion-substituted cobalt ferrite powders Co1-xZnxFe2O4 (x = 0⁻0.7) were prepared by the sol-gel auto-combustion process. The structural properties and magnetic of the samples were investigated with X-ray diffraction (XRD), superconducting quantum interference device, and a Mössbauer spectrometer. The results of XRD showed that the powder of a single cubic phase of ferrites calcined when kept at 800 °C for 3 h. The lattice constant increases with increase in Zn concentration, but average crystallite size does not decrease constantly by increasing the zinc content, which is related to pH value. It was confirmed that the transition from ferrimagnetic to superparamagnetic behaviour depends on increasing zinc concentration by Mössbauer spectra at room temperature. Magnetization at room temperature increases for x ≤ 0.3, but decreases for increasing Zn2+ ions. The magnetization of Co0.7Zn0.3Fe2O4 reached maximum value (83.51 emu/g). The coercivity decreased with Zn2+ ions, which were doped on account of the decrease of the anisotropy constant.

11.
Artigo em Inglês | MEDLINE | ID: mdl-29861765

RESUMO

Background. Scutellaria baicalensis (SB) is commonly used in traditional Chinese medicine for chronic inflammatory diseases. This study aims to investigate the effects of the early intervention with SB on airway remodeling in a well-established rat model of COPD induced by cigarette smoking. Methods. COPD model in Sprague Dawley (SD) rats were established by exposing them to smoke for 6 days/week, for 12 weeks, 24 weeks, or 36 weeks. Meanwhile, rats were randomly divided into normal control group, model group, Budesonide (BUD) group, and the SB (low, middle, and high) dose groups with 8 rats in each group and 3 stages (12 weeks, 24 weeks, and 36 weeks). After treatment, the pulmonary function was evaluated by BUXCO system and the morphology changes of the lungs were observed with HE and Masson staining. The serum IL-6, IL-8, and IL-10 and TNF-α, TGF-beta (TGF-ß1), MMP-2, MMP-9, and TIMP-1 levels in BALF were detected by ELISA-kit assay. The protein expression levels of AKT and NF-κB (p65) were determined by western blot (WB). Results. The oral of SB significantly improved pulmonary function (PF) and ameliorated the pathological damage and attenuated inflammatory cytokines infiltration into the lungs. Meanwhile, the levels of TGF-ß, MMP-2, MMP-9, and TIMP-1 were partially significantly decreased. The levels of PI3K/AKT/NF-κB pathway were also markedly suppressed by SB. Conclusions. SB could significantly improve the condition of airway remodeling by inhibiting airway inflammation and partially quenching TGF-ß and MMPs via PI3K/AKT/NF-κB pathway.

12.
J Appl Biomater Funct Mater ; 16(1_suppl): 93-100, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29618245

RESUMO

BACKGROUND: A multiferroic material can simultaneously show two or more basic magnetic properties, including ferromagnetism, antiferromagnetism, and ferroelectricity. BiFeO3 is a multiferroic material with a rhombohedral distorted perovskite structure. Doping can reduce the volatility of Bi and greatly improve the magnetoelectric properties of BiFeO3. METHODS: To investigate the influence of the doping content we used the following analytical methods: X-ray powder diffraction (XRD), scanning electron microscopy (SEM), microwave network analysis (PNA-N5244A), and the Superconducting Quantum Interference Device (Quantum Design MPMS) test. RESULTS: With the increase of Ca2+ concentration in the solution, the grain size of Bi1- xCa xFeO3 becomes smaller, showing the role of Ca2+ ions as the dopant for fine grains. The calcination temperatures are the major causes for the saturated magnetization. The residual magnetization ( Mr) and the coercive force ( Hc) decrease linearly with the increase of x value, and due to the effect of Ca2+ substitution at Bi3+ sites, which causes the valence change of Fe and/or the oxygen vacancies. CONCLUSIONS: The XRD result indicates that the diffraction peak emerges with the increase of Ca2+ and the main diffraction peak achieves a high angle. The best calcining temperature is 600 °C, and the morphology is very dependent on the calcining temperature.


Assuntos
Bismuto/química , Cálcio/química , Compostos Férricos/química , Campos Magnéticos
13.
Front Physiol ; 9: 58, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29467669

RESUMO

Chronic obstructive pulmonary disease (COPD) is a common cause of mortality worldwide. The current lack of an animal model that can be established within a certain time frame and imitate the unique features of the disease is a major limiting factor in its study. The present study established and evaluated an animal model of COPD that represents the early and advanced stage features using short-, middle-, and long-term sidestream cigarette smoke (CS) exposure. One hundred and nine Sprague-Dawley rats were randomly divided into 10 groups for different periods of sidestream CS exposure or no exposure (i.e., normal groups). The rats were exposed to CS from 3R4F cigarettes in an exposure chamber. Histological analysis was performed to determine pathological changes. We also conducted open-field tests, lung function evaluations, and cytokine analysis of the blood serum, bronchoalveolar lavage fluid, and lung tissue. The lung tissue protein levels, blood gases, and were also analyzed. As the CS exposure time increased, the indicators associated with oxidative stress, inflammatory responses, and airway remodeling were greater in the CS exposure groups than in the normal group. At 24 and 36 weeks, the COPD model rats displayed the middle- and advanced-stage features of COPD, respectively. In the 8-week CS exposure group, after the CS exposure was stopped for 4 weeks, inflammatory responses and oxidative responses were ameliorated and lung function exacerbation was reduced compared with the 12-week CS exposure group. Therefore, we established a more adequate rat model of sidestream CS induced COPD, which will have great significance for a better understanding of the pathogenesis of COPD and drug effectiveness evaluation.

14.
Artigo em Inglês | MEDLINE | ID: mdl-28003846

RESUMO

Paeoniflorin (PF), a monoterpene glucoside, might have an effect on the oxidative stress. However, the mechanism is still unknown. In this study, we made the COPD model in Sprague-Dawley (SD) rats by exposing them to the smoke of 20 cigarettes for 1 hour/day and 6 days/week, for 12 weeks, 24 weeks, or 36 weeks. Our findings suggested that smoke inhalation can trigger the oxidative stress from the very beginning. A 24-week treatment of PF especially in the dosage of 40 mg/kg·d can attenuate oxygen stress by partially quenching reactive oxygen species (ROS) and upregulating antioxidant enzymes via an Nrf2-dependent mechanism.

16.
PLoS One ; 10(2): e0116427, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25658752

RESUMO

BACKGROUND: Dysfunction of central and skin Hypothalamic-Pituitary-Adrenal (HPA) axis play important roles in pathogenesis of atopic dermatitis (AD). Our previous studies showed that several Chinese herbs could improve HPA axis function. In this study, we evaluated the anti-inflammatory effects of BuShenYiQi granule (BSYQ), a Chinese herbs formula, in AD mice and explored the effective mechanism from regulation of HPA axis. METHODS: The ovalbumin (OVA) induced AD mice model were established and treated with BSYQ. We evaluated dermatitis score and histology analysis of dorsal skin lesions, meanwhile, serum corticosterone (CORT), adrenocorticotropic hormone (ACTH), corticotropin-releasing hormone (CRH) and inflammatory cytokines were determined by ELISA. The changes of CRH/proopiomelanocortin(POMC) axis elements, corresponding functional receptors and crucial genes of glucocorticosteroidogenesis in the skin were measured by quantitative real-time PCR and western blot, respectively. RESULTS: The symptoms and pathological changes in skin of AD mice were significantly improved and several markers of inflammation and allergy descended obviously after BSYQ treatment. We found that AD mice had insufficient central HPA tone, but these conditions were markedly improved after BSYQ treatment. The AD mice also showed a disturbed expression of skin HPA. In lesion skin of AD mice, the mRNA and protein expressions of CRH decreased significantly, on the contrary, POMC and cytochrome P450 side-chain cleavage enzyme (CYP11A1) increased markedly, meanwhile, NR3C1 (mouse GR), CRHR2 and 11-hydroxylase type 1(CYP11B1) were reduced locally. Most of these tested indexes were improved after BSYQ treatment. CONCLUSIONS: AD mice displayed the differential expression pattern of central and skin HPA axis and BSYQ treatment significantly alleviated the symptoms of AD mice and presented anti-inflammatory and anti-allergic effects via regulating the expression of central and skin HPA axis.


Assuntos
Anti-Inflamatórios/farmacologia , Dermatite Atópica/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Fenômenos Fisiológicos da Pele/efeitos dos fármacos , Hormônio Adrenocorticotrópico/sangue , Animais , Western Blotting , Corticosterona/sangue , Hormônio Liberador da Corticotropina/sangue , Citocinas/sangue , Ensaio de Imunoadsorção Enzimática , Sistema Hipotálamo-Hipofisário/fisiologia , Camundongos , Sistema Hipófise-Suprarrenal/fisiologia , Reação em Cadeia da Polimerase em Tempo Real
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