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Organic single crystals quickly emerge as dense yet light and nearly defect-free media for emissive elements. Integration of functionalities and control over the emissive properties is currently being explored for a wide range of these materials to benchmark their performance against organic emissive materials diluted in powders or films. Here, we report mechanically flexible emissive chiral organic crystals capable of an unprecedented combination of fast, reversible, and low-fatigue responses. UV-excited single crystals of both enantiomers of the material, 4-chloro-2-(((1-phenylidene)imino)methyl)phenol, exhibit a drastic yet reversible change in the emission color from green to orange-yellow within a second and can be cycled at least 2000â times. The photoresponse was found to depend strongly on the excitation intensity and temperature. Combining chirality, mechanical compliance, rapid emission switching, multiple responses, and writability by UV light, this material provides a unique and versatile platform for developing organic crystal-based materials for on-demand signal transfer, information storage, and cryptography.
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Background: Retinal disorders cause substantial visual burden globally. Accurate estimates of the vision loss due to retinal diseases are pivotal to inform optimal eye health care planning and allocation of medical resources. The purpose of this study is to describe the proportion of visual impairment and blindness caused by major retinal diseases in China. Methods: A nationwide register-based study of vitreoretinal disease covering all 31 provinces (51 treating centres) of mainland China. A total of 28 320 adults diagnosed with retinal diseases were included. Participants underwent standardised ocular examinations, which included best-corrected visual acuity (BCVA), dilated-fundus assessments, and optical coherence tomography. Visual impairment and blindness are defined using BCVA according to the World Health Organization (WHO) (visual impairment: <20/63-≥20/400; blindness: <20/400) and the United States (visual impairment: <20/40-≥20/200; blindness: <20/200) definitions. The risk factors of vision loss were explored by logistic regression analyses. Results: Based on the WHO definitions, the proportions for unilateral visual impairment and blindness were 46% and 18%, respectively, whereas those for bilateral visual impairment and blindness were 31% and 3.3%, respectively. Diabetic retinopathy (DR) accounts for the largest proportion of patients with visual impairment (unilateral visual impairment: 32%, bilateral visual impairment: 60%) and blindness (unilateral blindness: 35%; bilateral blindness: 64%). Other retinal diseases that contributed significantly to vision loss included age-related macular degeneration, myopic maculopathy, retinal vein occlusion, and rhegmatogenous retinal detachment and other macular diseases. Women (bilateral vision loss: P = 0.011), aged patients (unilateral vision loss: 45-64 years: P < 0.001, ≥65 years: P < 0.001; bilateral vision loss: 45-64 years: P = 0.003, ≥65 years: P < 0.001 (reference: 18-44 years)) and those from Midwest China (unilateral and bilateral vision loss: both P < 0.001) were more likely to suffer from vision loss. Conclusions: Retinal disorders cause substantial visual burden among patients with retinal diseases in China. DR, the predominant retinal disease, is accountable for the most prevalent visual disabilities. Better control of diabetes and scaled-up screenings are warranted to prevent DR. Specific attention should be paid to women, aged patients, and less developed regions.
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Retinopatía Diabética , Degeneración Macular , Enfermedades de la Retina , Baja Visión , Personas con Daño Visual , Adulto , Humanos , Femenino , Anciano , Agudeza Visual , Ceguera/epidemiología , Ceguera/etiología , Baja Visión/etiología , Baja Visión/complicaciones , Trastornos de la Visión/etiología , Trastornos de la Visión/complicaciones , Enfermedades de la Retina/epidemiología , Enfermedades de la Retina/complicaciones , Degeneración Macular/complicaciones , Degeneración Macular/epidemiología , PrevalenciaRESUMEN
Woven architectures are prepared by physical entanglement of fibrous components to expand one-dimensional material into two-dimensional sheets with enhanced strength and resilience to wear. Here, we capitalize on the elastic properties of long organic crystals with a high aspect ratio to prepare an array of centimeter-size woven network structures. While being robust to mechanical impact, the woven patches are also elastic due to effective stress dissipation by the elasticity of the individual warp and weft crystals. The thermal stability of component crystals translates into favorable thermoelastic properties of the porous woven structures, where the network remains elastic over a range of 300 K. By providing means for physical entanglement of organic crystals, the weaving circumvents the natural limitation of the small size of slender organic crystals that is determined by their natural growth, thereby expanding the prospects for applications of organic crystals from one-dimensional entities to expandable, two-dimensional robust structures.
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BACKGROUND: Lupus nephritis (LN) is a serious complication of systemic lupus erythematosus (SLE), and its pathogenesis is not fully understood. Previously, we showed that fractalkine (FKN) expression was positively correlated with the severity of LN. Here, we aimed to study the role of the Hippo signaling pathway (HSP) and its interaction with FKN in LN in an attempt to provide novel strategies for LN treatment. METHODS: In this study, lipopolysaccharide (LPS)/interferon-γ (IFN-γ)-stimulated THP-1 cells were co-cultured with FKN up-regulated or down-regulated kidney epithelial cells Hkb20. FKN-knockout (KO-FKN) mice were used to construct LN model. Flow cytometric analysis, quantitative real-time polymerase chain reaction (qRT-PCR), enzyme-linked immunosorbent assay (ELISA), pathological staining, Western blot, and immunofluorescence (IF) staining were employed to investigate the role of FKN and its interaction with the Hippo signaling pathway (HSP) in LN. RESULTS: Up-regulation of FKN in kidney epithelial cells was associated with increased macrophage activation. FKN overexpression in kidney epithelial cells suppressed apoptosis, inflammation levels, and M1 polarization of THP-1 cells and inhibited the HSP. Oppositely, FKN knockdown in kidney epithelial cells increased apoptosis, inflammation, and M1 polarization and activated the HSP. HSP inhibitor reversed the effect of FKN knockdown on THP-1 cells. In LN mice, FKN knockout and YAP inhibitor decreased the levels of renal function markers, alleviated kidney injury induced by LN, and inhibited macrophage activation in LN mice. CONCLUSIONS: FKN down-regulation reduced the activation of macrophages in renal tissue and alleviated kidney damage by activating HSP. The regulatory effect of FKN on HSP should be confirmed in patients with LN, and the mechanism of FKN in LN should be further explored.
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Lupus Eritematoso Sistémico , Nefritis Lúpica , Animales , Humanos , Ratones , Quimiocina CX3CL1/metabolismo , Células Epiteliales/metabolismo , Vía de Señalización Hippo , Inflamación/metabolismo , Riñón/patología , Lupus Eritematoso Sistémico/metabolismo , Nefritis Lúpica/patología , Activación de MacrófagosRESUMEN
The capability of stimulated response by mechanical deformation to induce motion or actuation is the foundation of lightweight organic, dynamic materials for designing light and soft robots. Various biomimetic soft robots are constructed to demonstrate the vast versatility of responses and flexibility in shape-shifting. We now report that the integration of organic molecular crystals and polymers brings about synergistic improvement in the performance of both materials as a hybrid materials class, with the polymers adding hygroresponsive and thermally responsive functionalities to the crystals. The resulting hybrid dynamic elements respond within milliseconds, which represents several orders of magnitude of improvement in the time response relative to some other type of common actuators. Combining molecular crystals with polymers brings crystals as largely overlooked materials much closer to specific applications in soft (micro)robotics and related fields.
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Hybrid materials capitalize on the properties of individual materials to attain a specific combination of performance assets that is not available with the individual components alone. We describe a straightforward approach to preparation of sandwich-type hybrid dynamic materials that combine metals as electrically conductive components and polymers as bending, momentum-inducing components with flexible organic crystals as mechanically compliant and optically transducive medium. The resulting hybrid materials are conductive to both electricity and light, while they also respond to changes in temperature by deformation. Depending on the metal, their conductivity ranges from 7.9 to 21.0 S µmâ1. The elements respond rapidly to temperature by curling or uncurling in about 0.2 s, which in one typical case corresponds to exceedingly fast deformation and recovery rates of 2187.5° sâ1 and 1458.3° sâ1, respectively. In cyclic operation mode, their conductivity decreases less than 1% after 10,000 thermal cycles. The mechanothermal robustness and dual functionality favors these materials as candidates for a variety of applications in organic-based optics and electronics, and expands the prospects of application of organic crystals beyond the natural limits of their dynamic performance.
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BACKGROUND: The long chain non-coding RNA HOXA11-OS was recently identified. Increasing studies have shown that HOXA11-OS has regulatory effects on genes in gastric cancer, prostate cancer, and various kidney diseases, but research on its role in systemic lupus erythematosus is still lacking. The present study aimed to investigate the role of HOXA11-OS in the regulation of podocyte autophagy in the development of lupus nephritis (LN) and its potential molecular mechanism. METHODS: mRNA and protein expression of the target gene (i.e., Cyr61) was detected by quantitative real-time polymerase chain reaction, western blotting, and immunofluorescence. Mouse podocytes were induced using serum immunoglobulin G (IgG) from patients with lupus and their viability was detected using the cell counting kit-8 assay. The interaction of miR-124-3p with HOXA11-OS and Cyr61 was analyzed by double luciferase reporter gene assay. Serum autoantibody levels were detected by enzyme-linked immunosorbent assay. Pathological lesions in the kidney tissue were detected by hematoxylin-eosin and periodate-Schiff staining. The independent samples t-test was used for comparing two groups, and one-way analysis of variance for comparing multiple groups. RESULTS: HOXA11-OS was highly expressed in LN tissues, serum, and cells, and the expression of some key autophagy factors and Cyr61 was significantly increased, while miR-124-3p expression was significantly decreased. In vitro, LN-IgG inhibited podocyte activity, increased autophagy and Cyr61 expression, and aggravated podocyte injury in a time- and dose-dependent manner. As a competitive endogenous RNA of miR-124-3p, HOXA11-OS promoted the expression of Cyr61, thus enhancing the autophagy increase induced by LN-IgG and aggravating podocyte injury. Knockdown of HOXA11-OS had the opposite effect. miR-124-3p mimic or Cyr61 knockdown restored the high expression of autophagy factors and Cyr61 induced by HOXA11-OS overexpression and alleviated podocyte injury. Further in vivo experiments showed that injection of sh-HOXA11-OS adeno-associated virus downregulated HOXA11-OS and significantly alleviated renal damage in lupus mice. CONCLUSIONS: HOXA11-OS is involved in the occurrence and development of LN by regulating podocyte autophagy through miR-124-3p/Cyr61 sponging, which may provide a good potential therapeutic target for LN.
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Nefritis Lúpica , MicroARNs , Podocitos , ARN Largo no Codificante , Animales , Masculino , Ratones , Autofagia , Inmunoglobulina G , Nefritis Lúpica/genética , MicroARNs/genética , Factores de TranscripciónRESUMEN
Flexible organic crystals with unique mechanical properties and excellent optical properties are of paramount significance for their wide applications in various research fields such as adaptive optics and soft robotics. However, low-temperature-resistant flexible organic crystal with circularly polarized luminescence (CPL) has never been reported. Herein, chiral organic crystals with CPL activity and low-temperature flexibility (77â K) are fabricated by the solvent diffusion method from chiral Schiff base, S(R)-4-bromo-2-(((1-phenylethyl)imino)methyl)phenol (S(R)-BPEMP). The corresponding chirooptical properties for the two enantiomeric crystals were thoroughly investigated, including the measurements of circular dichroism (CD) and CPL. To the best of our knowledge, this is the first report on low-molecular-weight flexible organic crystals with CPL activity, and we believe that the results will give a new impetus to the research of organic crystals.
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BACKGROUND: Podocyte injury is a major biomarker of primary glomerular disease, which leads to massive proteinuria and kidney failure. The increased production of the chemokine, fractalkine (FKN, CX3CL1), is a hallmark of multiple inflammatory diseases. However, the underlying mechanism of FKN in podocyte injury remains unknown. METHODS: In this study, we performed an LPS infusion model in FKN knockout (FKN-/-, FKN-KO) mice. In cultured podocytes, we used plasmids to knockdown FKN and treated the podocytes with PI3K/Akt inhibitor (LY294002). Haematoxylin and eosin (HE) staining, Western Bolt, Co-immunoprecipitation (Co-IP), Immunofluorescence staining and flow cytometric analysis were employed to establish the role of FKN in podocyte injury. RESULTS: LPS stimulation resulted in kidney damage, increased the expression of the Bcl-2 family apoptosis protein, and decreased podocyte marker protein (nephrin, podocin and WT1) abundance compared with the WT mice. LPS-induced FKN-KO mice exhibited reduced lethality and inflammatory cell infiltration, podocyte apoptosis, and PI3K/Akt signal pathway inhibition compared to WT mice. In cultured podocytes, the interaction between FKN and the PI3K/Akt signalling pathway was well confirmed. FKN knockdown reduced podocyte apoptosis by regulating the Bcl-2 family; however, this protective effect was reversed by the co-administration of a PI3K/Akt inhibitor (LY294002). CONCLUSION: Overall, these findings reveal a novel mechanistic property of FKN, PI3K/Akt signalling, and podocyte apoptosis.
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Lesión Renal Aguda , Podocitos , Lesión Renal Aguda/inducido químicamente , Lesión Renal Aguda/genética , Lesión Renal Aguda/prevención & control , Animales , Apoptosis , Quimiocina CX3CL1 , Lipopolisacáridos/farmacología , Ratones , Fosfatidilinositol 3-Quinasas/metabolismo , Fosfatidilinositol 3-Quinasas/farmacología , Podocitos/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/farmacología , Transducción de SeñalRESUMEN
Objective To investigate the mechanism of CX3CL1/fractalkine (FKN) in lipopolysaccharide (LPS)-induced apoptosis of mouse RAW264.7 macrophages. Methods RAW264.7 macrophages were infected with FKN overexpression or knockdown lentivirus plasmids containing red fluorescent protein and treated with LPS. The apoptosis of RAW264.7 macrophages was detected by flow cytometry. The expression levels of FKN, Wnt4, ß-catenin, cleaved caspase-3(c-caspase-3), c-caspase-9, BAX and cytochrome C (CytC) proteins were measured by Western blotting. The expression and localization of c-caspase-3 and c-caspase-9 in RAW264.7 macrophages were determined by immunofluorescence cytochemistry. Results Compared with control group, the apoptosis rate and the protein levels of FKN, Wnt4, ß-catenin, c-caspase-3, c-caspase-9, BAX and CytC increased significantly in LPS group. Compared with LPS group, the apoptosis rate of FKN overexpression combined with LPS group was significantly decreased. The protein levels of FKN, Wnt4 and ß-Catenin reported an increase, while the protein levels of c-caspase-3, c-caspase-9, BAX, CytC and localization of c-caspase-3 and c-caspase-9 in the cytoplasm showed a decrease in FKN overexpression combined with LPS group. The opposite results were observed in FKN knockdown combined with LPS group. Conclusion CX3CL1/FKN can activate Wnt/ß-catenin signal pathway, downregulate the key proteins expression of mitochondrial apoptosis pathway, and reduce LPS-induced apoptosis of RAW264.7 macrophages.
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Lipopolisacáridos , beta Catenina , Animales , Apoptosis , Quimiocina CX3CL1/metabolismo , Quimiocina CX3CL1/farmacología , Lipopolisacáridos/metabolismo , Lipopolisacáridos/farmacología , Macrófagos/metabolismo , Ratones , Vía de Señalización Wnt , beta Catenina/genética , beta Catenina/metabolismoRESUMEN
Fractalkine (CX3CL1, FKN), a CX3C gene sequence inflammatory chemokine, has been found to have pro-inflammatory and pro-adhesion effects. Macrophages are immune cells with a critical role in regulating the inflammatory response. The imbalance of M1/M2 macrophage polarization can lead to aggravated inflammation. This study attempts to investigate the mechanisms through which FKN regulates macrophage activation and the acute kidney injury (AKI) involved in inflammatory response induced by lipopolysaccharide (LPS) by using FKN knockout (FKN-KO) mice and cultured macrophages. It was found that FKN and Wnt/ß-catenin signalling have a positive interaction in macrophages. FKN overexpression inhibited LPS-induced macrophage apoptosis. However, it enhanced their cell viability and transformed them into the M2 type. The effects of FKN overexpression were accelerated by activation of Wnt/ß-catenin signalling. In the in vivo experiments, FKN deficiency suppressed macrophage activation and reduced AKI induced by LPS. Inhibition of Wnt/ß-catenin signalling and FKN deficiency further mitigated the pathologic process of AKI. In summary, we provide a novel mechanism underlying activation of macrophages in LPS-induced AKI. Although LPS-induced murine AKI was unable to completely recapitulate human AKI, the positive interactions between FKN and Wnt/ß-catenin signalling pathway may be a therapeutic target in the treatment of kidney injury.
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Lesión Renal Aguda/metabolismo , Quimiocina CX3CL1/metabolismo , Activación de Macrófagos , Vía de Señalización Wnt , Lesión Renal Aguda/etiología , Animales , Apoptosis , Línea Celular , Quimiocina CX3CL1/genética , Lipopolisacáridos/toxicidad , Ratones , Ratones Endogámicos C57BL , beta Catenina/metabolismoRESUMEN
Fractalkine (FKN) is a chemokine with several roles, including chemotaxis; adhesion; and immune damage, which also participates in cell inflammation and apoptosis and responds to the pathogenesis of autoimmune diseases. Given the involvement of regulatory T cells (Treg) cells in autoimmune diseases, this study investigated the regulatory mechanism of FKN in renal injury and Treg apoptosis via the p38 mitogen-activated protein kinase (p38MAPK) signaling pathway in lupus-prone mice. Lupus was induced in BALB/c female mice by injection of pristane, followed by isolation of CD4+CD25+ Treg cells from the spleen of lupus model mice. To deplete FKN, mice received injection of an anti-FKN antibody, and Treg cells were transfected with FKN small-interfering RNA. Lupus mice and Treg cells were treated with the p38MAPK inhibitor SB203580 and activator U-46619, respectively, and urine protein and serum urea nitrogen, creatinine, and autoantibodies were measured and renal histopathological changes analyzed. We determined levels of FKN, phosphorylated p38 (p-p38), and forkhead box P3 (FOXP3) in renal tissue and Treg cells, and analyzed apoptosis rates and levels of key apoptotic factors in Treg cells. The renal FKN and p-p38 levels increased, whereas renal FOXP3 level decreased in lupus-prone mice. Treatment with the anti-FKN antibody and the p38MAPK inhibitor ameliorated proteinuria and renal function, significantly reducing serum autoantibody, renal FKN, and p-p38 levels while increasing renal FOXP3 level in lupus-prone mice. Moreover, FKN knockdown and administration of the p38MAPK inhibitor reduced apoptosis and levels of pro-apoptotic factors, increased levels of anti-apoptotic factors, and suppressed activation of p38MAPK signaling in Treg cells derived from lupus model mice. Furthermore, treatment with the p38MAPK activator U-46619 had the opposite effect on these cells. These data indicated that depletion of FKN ameliorated renal injury and Treg cell apoptosis via inhibition of p38MAPK signaling in lupus nephritis, suggesting that targeting FKN represents a potential therapeutic strategy for treating Lupus nephritis.
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Lesión Renal Aguda/tratamiento farmacológico , Apoptosis/efectos de los fármacos , Quimiocina CX3CL1/farmacología , Nefritis Lúpica/tratamiento farmacológico , Linfocitos T Reguladores/efectos de los fármacos , Proteínas Quinasas p38 Activadas por Mitógenos/efectos de los fármacos , Lesión Renal Aguda/inmunología , Lesión Renal Aguda/metabolismo , Animales , Apoptosis/fisiología , Modelos Animales de Enfermedad , Factores de Transcripción Forkhead/metabolismo , Riñón/inmunología , Riñón/metabolismo , Nefritis Lúpica/metabolismo , Ratones Endogámicos BALB C , Transducción de Señal/inmunología , Linfocitos T Reguladores/inmunología , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismoRESUMEN
Heat capacity is an important and fundamental thermodynamic parameter in materials. The temperature-dependent heat capacity (HC) was studied extensively. Here, the universal correlation between the experimental heat capacity Cp and the coefficient of thermal expansion ß in reference solids at high temperatures: Cp = Co + Eß (C0 and E: constants) and the volume-dependent heat capacity CTE in the temperature range from several Kelvins to melting temperatures is quantitatively determined: CTE = Eß, and a new phenomenological model of the experimental heat capacity below the melting temperature in the volume dimension is established: Cp = CT + CTE (the non-volume-dependent heat capacity CT = C0fD, fD: Debye function). Previous harmonic and anharmonic HC models explain the HC at low temperatures and high temperatures, respectively. The new model successfully explains the HC at the whole temperature range below the melting temperature and quantitatively determines the change behavior of the temperature and volume in solids after absorbing the heat.
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Deferoxamine, deferiprone, and deferasirox are used for the treatment of systemic iron overload, although they possess limitations due to lack of oral activity, lower efficacy, and side effects. These limitations led to a search for an orally active iron chelator with an improved therapeutic index. The lower efficacy of deferiprone is due to rapid glucuronidation, leading to the formation of a nonchelating metabolite. Here, we demonstrate that the influence of metabolism can be reduced by introducing a sacrificial site for glucuronidation. A log P-guided investigation of 20 hydroxpyridinones led to the identification of CN128. The Fe(III) affinity and metal selectivity of CN128 are similar to those of deferiprone, the log P value is more lipophilic, and its iron scavenging ability is superior. Overall, CN128 was demonstrated to be safe in a range of toxicity assessments and is now in clinical trials for the treatment of ß-thalassemia after regular blood transfusion.
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Quelantes del Hierro/administración & dosificación , Quelantes del Hierro/química , Sobrecarga de Hierro/tratamiento farmacológico , Piridonas/administración & dosificación , Piridonas/química , Administración Oral , Animales , Relación Dosis-Respuesta a Droga , Cobayas , Humanos , Sobrecarga de Hierro/sangre , Ratones , Ratas , Ratas Sprague-Dawley , Distribución Tisular/efectos de los fármacos , Distribución Tisular/fisiologíaRESUMEN
BACKGROUND: Several societies and associations have produced and disseminated clinical practice guidelines (CPGs) for gestational diabetes mellitus (GDM). However, the quality of such guidelines has not been appraised so far. This study aims to evaluate the quality of CPGs for GDM published in the last decade using the AGREE II instrument. METHODS: A systematic search of the National Institute for Health and Care Excellence, New Zealand Guidelines Group, Scottish Intercollegiate Guidelines Network, Medlive, American Diabetes Association, Canadian Diabetes Association, International Diabetes Federation, as well as PubMed, Web of Science, Embase, China National Knowledge Infrastructure, Wanfang Chinese Periodical Database, and VIP Chinese Periodical Database was conducted from inception to June 2018. The quality was assessed by four trained researchers independently, using the AGREE IIinstrument. RESULTS: A total of 13 guidelines, published from 2009 to 2018, were finally included. Among them, 11 guidelines were evidence-based guidelines, and 2 were expert consensus. Scores for each of the six AGREE II domains(Median ± IQR) were 94 ± 11, 89 ± 53, 58 ± 37, 100 ± 6, 79 ± 48, 100 ± 71 and 67% ± 42%, and guidelines based on expert consensus generally scored lower than evidence-based guidelines (Z = -2.201, p = 0.028). Overall score of 10 guidelines were 5 points and above, and four guidelines were 7 points. Among six domains, two domains: Scope and Purpose, and Clarity of Presentation, had high scores; however, the domains of Rigor of Development, Stakeholder Involvement and Editorial Independence received lower scores. CONCLUSIONS: In general, the methodological quality of GDM guidelines is high, and evidence-based guidelines are superior to expert consensus. However, the domains of Rigor of Development, Stakeholder Involvement and Editorial Independence still need improvement. A systematic approach in the development of these guidelines and updating timely is needed. In some regions, more attention for guideline adaptation is recommended.
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Diabetes Gestacional/terapia , Guías de Práctica Clínica como Asunto/normas , Bases de Datos Factuales , Femenino , Humanos , EmbarazoRESUMEN
Microgravity crystal growth experiment for the growth of In0.11Ga0.89Sb was performed at the Chinese recoverable satellite through the space program SJ-10. This experiment is aimed to understand the melt formation and growth kinetics of In x Ga1-x Sb solid solution with higher indium composition, because their segregation coefficient was higher than the crystals with lower indium compositions. The target composition and uniformity were achieved with higher growth rate under microgravity, whereas the uniformity in composition was not achieved under normal gravity. The growth and dissolution were affected mainly by the steady state equilibrium in the melt composition because of the convection under normal gravity. The non-steady state equilibrium in the melt composition under microgravity helped to achieve a higher growth rate and compositional homogeneity at higher indium composition of In x Ga1-x Sb solid solution.
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A Sol-gel method assisted with spin-coating has been successfully used to grow orthorhombic GaFeO3 epitaxial films on SrTiO3 (111) substrates for the first time. The film with Pna21 crystal structure has been grown along the c-axis. The rocking curve of (004) reflection shows that the Full-Width at Half-Maximum (FWHM) value could be determined to be 0.230°, indicating good single crystallinity and high quality. X-ray Φ scan reveals a three-fold symmetry of the substrate and a six-fold symmetry of the film, respectively. The in-plane domains rotate 60° from each other in the film. Uniform film with dense structure, columnar grains with similar grain size was obtained. The thickness of the film was evaluated to be ~170 nm. The roughness value (RMS) measured by AFM was 4.5 nm, revealing a flat film. The in-plane Magnetization versus Magnetic field (M-H) curve at 5 K performs a typical ferri- or ferromagnetic hysteresis loop with a saturated magnetization (Ms) value of 136 emu/cm³. The Curie temperature could be determined to be 174 K. Compared to Pulsed Laser Deposition (PLD), the sol-gel method can prepare large area films with low cost. These new films show promising applications in multiferroic devices.
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The effect of Yb3+ ions on upconversion luminescence and thermal properties of Tm3+/Yb3+ co-doped La2O3-Nb2O5-Ta2O5 glasses has been studied. Glass transition temperature is around 740 °C, indicating high thermal stability. The effect of Yb3+ ions on the thermal stability is not obvious. Both the glass forming ability and the upconversion luminescence first increase and then decrease with the increase of Yb3+ ions. The glasses perform low glass forming ability with ΔT around 55 °C. Blue and red emissions centered around 477, 651, and 706 nm are obtained at the excitation of 976 nm laser. The upconversion luminescence mechanism is energy transfer from Yb3+ to Tm3+ mixed with two- and three- photon processes. The thermal kinetic Differential Thermal Analysis (DTA)-analysis indicates that the average activation energy first increases and then decreases with the increase of Yb3+ ions. This result can be introduced in order to improve upconversion luminescence of glasses by crystallization in the future. Tm3+/Yb3+ co-doped La2O3-Nb2O5-Ta2O5 glasses with good upconversion and thermal properties show promising applications in solid-state laser, optical temperature sensing.
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Bifenthrin (BF), as a chiral pyrethroid, is widely used to control field and household pests in China. At present, the commercial BF is a mixed compound containing cis isomers (cis-BF) including two enantiomers of 1R-cis-BF and 1S-cis-BF. In the present study, the two individual cis-BF enantiomers were separated by a preparative supercritical fluid chromatography. Then, four week-old adolescent male ICR mice were orally administered 1R-cis-BF and 1S-cis-BF separately daily for 3 weeks at doses of 0, 7.5 and 15 mg/kg/day, respectively. Results showed that the transcription status of some genes involved in cholesterol synthesis and transport as well as testosterone (T) synthesis in the testes were influenced by cis-BF enantiomers. Especially, we observed that the transcription status of key genes on the pathway of T synthesis including cytochrome P450 cholesterol side-chain cleavage enzyme (P450scc) and cytochrome P450 17α-hydroxysteroid dehydrogenase (P45017α)) were selectively altered in the testis of mice when treated with 1S-cis-BF, suggesting that it is the possible reason to explain why the lower serum T concentration in 1S-cis-BF treated group. Taken together, it concluded that both of the cis-BF enantiomers have the endocrine disruption activities, while 1S-cis-BF was higher than 1R-cis-BF in mice when exposed during the puberty. The data was helpful to understand the toxicity of cis-BF in mammals under enantiomeric level.
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Disruptores Endocrinos/toxicidad , Insecticidas/toxicidad , Piretrinas/toxicidad , Testículo/efectos de los fármacos , Animales , Peso Corporal/efectos de los fármacos , Enzima de Desdoblamiento de la Cadena Lateral del Colesterol/metabolismo , Ensayo de Inmunoadsorción Enzimática , Regulación de la Expresión Génica/efectos de los fármacos , Hidroxiesteroide Deshidrogenasas/metabolismo , Insecticidas/química , Masculino , Ratones , Ratones Endogámicos ICR , Estereoisomerismo , Testículo/metabolismo , Testosterona/sangreRESUMEN
Bifenthrin (BF) is one of the most commonly used pesticides among the synthetic pyrethroids. The effects of BF exposure on the induction of immunotoxicity and oxidative stress were studied both in adolescent and adult male ICR mice. Both the weights of the spleen and thymus decreased significantly in the adolescent mice when they were treated with 20 mg/kg BF for 3 weeks. We found that the 3-week oral administration of BF during puberty increased the transcriptional levels of the genes TNF and IL2 in the spleen and IL2 as well as IL4 in the thymus. The effect of BF exposure on the induction of oxidative stress was also studied in serum and liver samples. The total antioxidant capacity and activity of superoxide dismutase were altered significantly in the serum of the 20 mg/kg BF-treated adolescent mice, and the activity of glutathione peroxidase (GPX) decreased significantly in the serum of adolescent and adult mice after 3 weeks of oral administration of 20 mg/kg BF. Compared to serum, hepatic GSH content increased significantly in both the adolescent and adult mice exposed to 20 mg/kg BF; hepatic CAT and GPX activities were altered significantly, even in adolescent mice, after treatment with 10 mg/kg BF. Taken together, the results of this study suggest that exposure to BF, especially during puberty, has the potential to induce immunotoxicity accompanied by oxidative stress in male mice. These findings will help in elucidating the mechanism of toxicity induced by BF in mice.