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1.
Artículo en Inglés | MEDLINE | ID: mdl-39033848

RESUMEN

The impact of acute ammonia nitrogen (NH3-N) stress on the antioxidant, immune, and metabolic capabilities of the liver in juvenile yellowfin tuna (Thunnus albacares) is not yet fully understood. This study set NH3-N concentrations at 0 (natural seawater, control group), 5, and 10 mg/L, and sampled the liver at 6, 24, and 36 h for analysis. As time progresses, NH3-N exposure leads to an increase in malondialdehyde (MDA) concentrations. The activity of superoxide dismutase (SOD) and the relative expression levels of related genes, as well as the activity of immune enzymes and ATPase, decrease. The levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and interleukin-10 (IL-10) exhibit different fluctuation patterns. Low concentrations of NH3-N increase the activity of catalase (CAT) and glutathione peroxidase (GHS-PX) and the relative expression levels of the Na+K+-ATPase gene. The relative expression levels of the interleukin-6 receptor (IL-6r) gene show a decreasing trend. High concentrations of NH3-N decrease the activity of CAT, GSH-PX, and the relative expression levels of related genes. When the NH3-N concentration is below 5 mg/L, the stress duration should not exceed 36 h. When the NH3-N concentration is between 5 and 10 mg/L, the stress duration should not exceed 24 h, otherwise, it will have a negative impact on the liver of the juvenile yellowfin tuna. This study provides scientific data for the artificial breeding and recirculating aquaculture of juvenile yellowfin tuna.

2.
Angew Chem Int Ed Engl ; 63(30): e202405228, 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-38744669

RESUMEN

Nacre is a classic model, providing an inspiration for fabricating high-performance bulk nanocomposites with the two-dimensional platelets. However, the "brick" of nacre, aragonite platelet, is an ideal building block for making high-performance bulk nanocomposites. Herein, we demonstrated a strong and tough conductive nacre through reassembling aragonite platelets with bridged by MXene nanosheets and hydrogen bonding, not only providing high mechanical properties but also excellent electrical conductivity. The flexural strength and fracture toughness of the obtained conductive nacre reach ~282 MPa and ~6.3 MPa m1/2, which is 1.6 and 1.6 times higher than that of natural nacre, respectively. These properties are attributed to densification and high orientation degree of the conductive nacre, which is effectively induced by the combined interactions of hydrogen bonding and MXene nanosheets bridging. The crack propagations in conductive nacre are effectively inhibited through crack deflection with hydrogen bonding, and MXene nanosheets bridging between aragonite platelets. In addition, our conductive nacre also provides a self-monitoring function for structural damage and offers exceptional electromagnetic interference shielding performance. Our strategy of reassembling the aragonite platelets exfoliated from waste nacre into high-performance artificial nacre, provides an avenue for fabricating high-performance bulk nanocomposites through the sustainable reutilization of shell resources.

3.
Inorg Chem ; 62(1): 433-441, 2023 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-36574613

RESUMEN

An in-depth insight into the effect of nitrogen substitution on structural stabilization is important for the design of new spinel-type oxynitride materials with tailored properties. In this work, the crystal structures of ordered and disordered LiAl5O8 obtained by slow cooling and rapid quenching, respectively, were analyzed by a X-ray diffraction (XRD) Rietveld refinement and OccQP program. The variation in the bonding state of atoms in the two compounds was explored by the bond valence model, which revealed that the instability of spinel-type LiAl5O8 crystal structure at room temperature is mainly due to the severe under-bonding of the tetrahedrally coordinated Al cations. With the partial substitution of oxygen with nitrogen in LiAl5O8, a series of the nitrogen-stabilized spinel LiyAl(16+x-y)/3O8-xNx (0 < x < 0.5, 0 < y < 1) was successfully prepared. The crystal structures were systematically investigated by the powder XRD structural refinement combined with 7Li and 27Al magic-angle spinning nuclear magnetic resonance. All the Li+ ions entered the octahedra, while the Al resonances may be composed of multiple non-equivalent Al sites. The structural stability of spinel LiyAl(16+x-y)/3O8-xNx at ambient temperature was attributed to the cationic vacancies and high valence generated by the N ions, which alleviated the under-bonding state of the tetrahedral Al-O bond. This work provides a new perspective for understanding the composition-structure relationship in spinel compounds with multiple disorders.

4.
J Neurochem ; 160(3): 392-411, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34837397

RESUMEN

TBC1Domain Family Member 25 (TBC1D25) is a protein that contains a TBC/RAB-GTPase activating protein (GAP) domain, which was shown to participate in autophagy in previous studies. However, the role of TBC1D25 in cerebral ischemia-reperfusion (I/R) injury remains unknown. In this study, we found that the mRNA and protein expression levels of TBC1D25 decreased in mouse brain after I/R injury and primary cortical neurons treated with oxygen and glucose deprivation/reoxygenation (OGD/R). Then TBC1D25 knockout (KO) mice were applied to demonstrate that TBC1D25 ablation aggravated cerebral I/R-induced neuronal loss and infarct size. In addition, neuronal apoptosis and inflammation were significantly potentiated in the TBC1D25-KO group. In in vitro OGD/R model, TBC1D25 knockdown can attenuate neuronal cell viability and aggravate the process of inflammation and apoptosis. Conversely, over-expression of TBC1D25 in primary neurons ameliorated the aforementioned processes. Mechanistically, RNA-sequencing (RNA-seq) analysis revealed mitogen-activated protein kinase (MAPK) signaling pathway was the most significant pathway that contributed to TBC1D25-mediated brain I/R injury process. Through experimental verification, TBC1D25 deficiency increased the phosphorylation of the transforming growth factor-ß-activated kinase 1 (TAK1)-c-Jun N-terminal kinase (JNK)/p38 axis in neurons during the brain I/R injury. Furthermore, we found that TAK1 blockade abrogated the apoptosis and inflammatory response produced by TBC1D25 knockdown in vitro. In conclusion, this study is the first to demonstrate the functional significance of TBC1D25 in the pathophysiology of brain I/R injury, and the protective mechanism of TBC1D25 is dependent on the TAK1-JNK/p38 pathway.


Asunto(s)
Isquemia Encefálica/genética , Proteínas Activadoras de GTPasa/genética , Proteínas Quinasas JNK Activadas por Mitógenos/genética , Quinasas Quinasa Quinasa PAM/genética , Daño por Reperfusión/genética , Proteínas Quinasas p38 Activadas por Mitógenos/genética , Animales , Apoptosis , Isquemia Encefálica/fisiopatología , Proteínas Activadoras de GTPasa/deficiencia , Glucosa/deficiencia , Infarto de la Arteria Cerebral Media/genética , Infarto de la Arteria Cerebral Media/fisiopatología , Inflamación/genética , Inflamación/patología , Sistema de Señalización de MAP Quinasas/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Fosforilación , RNA-Seq , Daño por Reperfusión/fisiopatología
5.
Inorg Chem ; 61(11): 4743-4751, 2022 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-35258955

RESUMEN

An accurate knowledge of the elastic properties of materials is essential for material science and engineering applications. Four single crystals of nonstoichiometric alumina-rich spinel [Mg1-xAl2(1+x/3)O4] were obtained from sintered transparent ceramics for the investigation of its elastic properties. The disordered crystal structures were fully resolved by combining single-crystal structure refinement and a quadratic programming approach for the first time. The bond valence model and Brillouin scattering experiments were used to evaluate the bulk modulus (K), shear modulus (G), Young's modulus (E), and Poisson's ratio. The discrepancy between the theoretical and experimental results is <2.6%. The independent elastic constants (C11, C12, and C44) were determined from Brillouin scattering experiments. A negative Poisson's ratio, υ(110, 11̅0), was found to exist in all alumina-rich spinels, which means it is a partially auxetic material. Blackman diagram analysis was introduced to identify the interrelationships and trends in mechanical and bonding properties in alumina-rich spinels. The bond valence model was suggested to be an effective and accurate approach for predicting the elastic modulus of spinels, which provides a useful tool for the study of the composition-structure-property relationship of materials.

6.
Sensors (Basel) ; 22(8)2022 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-35458997

RESUMEN

Hydrogels of flexibility, strength, and conductivity have demonstrated broad applications in wearable electronics and soft robotics. However, it is still a challenge to fabricate conductive hydrogels with high strength massively and economically. Herein, a simple strategy is proposed to design a strong ionically conductive hydrogel. This ion-conducting hydrogel was obtained under the synergistic action by salting out the frozen mixture of polyvinyl alcohol (PVA) and graphene oxide (GO) using a high concentration of sodium chloride solution. The developed hydrogel containing only 5 wt% PVA manifests good tensile stress (65 kPa) and elongation (180%). Meanwhile, the PVA matrix doped with a small amount of GO formed uniformly porous ion channels after salting out, endowed the PVA/GO hydrogel with excellent ionic conductivity (up to 3.38 S m-1). Therefore, the fabricated PVA/GO hydrogel, anticipated for a strain sensor, exhibits good sensitivity (Gauge factor = 2.05 at 100% strain), satisfying working stability (stably cycled for 10 min), and excellent recognition ability. This facile method to prepare conductive hydrogels displays translational potential in flexible electronics for engineering applications.


Asunto(s)
Alcohol Polivinílico , Dispositivos Electrónicos Vestibles , Conductividad Eléctrica , Congelación , Grafito , Hidrogeles , Iones , Cloruro de Sodio
7.
Ecotoxicol Environ Saf ; 225: 112712, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34478980

RESUMEN

Acidized water environment can impact many physiological processes of aquatic animals. The response of the head kidney to acidification, especially the immune response, is of great significance to health. This study analyzed the histological and transcriptional changes under different acidification levels (C group, pH 8.1; P group, pH 7.4; E group, pH 3.5) in the short term (12 h, 36 h and 60 h) in the head kidney of juvenile L. calcarifer. The results showed that the acidification of the water environment caused tissue damage to the head kidney of L. calcarifer, and the damage appeared earlier and was stronger in the extreme pH group. The transcriptional response of L. calcarifer head kidney increased with the increase of acidification level. The two treatments transcriptional responses showed different trends in terms of time. After KEGG function enrichment, with the increase of stimulation time, the proportion of down-regulated pathways was increasing, and the types of pathway enrichment at different acidification levels were quite different at the initial stage. At 12 h, the first category in the P group with the most significant number of pathways was 'Metabolism', and the first category in the E group with the largest number of pathways was 'Human Diseases'. At 60 h, the enrichment pathways of the two groups were highly overlapping in immune-related pathways, which contained 26 common DEGs. They had a dominant expression pattern. In the P group, the expression level decreased with time. In the E group, the down-regulation degree of expression level at 12 h reached the level of the P group at 60 h, and the expression level remained low until 60 h. Through the correlation network, interferon regulatory factor 7 (IRF7), Tripartite motif containing-21 (TRIM21), Signal transducer and activator of transcription 1 (STAT1) and Signal transducer and activator of transcription 3 (STAT3) were found to have the most correlation with other genes. In this study, juvenile L. calcarifer showed different coping strategies to different levels of acute acidification stress, but all of them resulted in the extensive weakening of head kidney immune function.


Asunto(s)
Perciformes , Animales , Riñón Cefálico , Humanos , Concentración de Iones de Hidrógeno , Inmunidad
8.
Inorg Chem ; 59(23): 17009-17017, 2020 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-33216542

RESUMEN

The deep understanding of the crystal structure and composition-structure relationship is important for modifying and designing solids to obtain functional materials with customized properties. However, because of multiple compositions and complex structures in some spinel solid solutions, the composition-structure relationship is unknown, or becomes very complicated and difficult to be controlled. In this work, the solid-state magic-angle spinning nuclear magnetic resonance (MAS NMR) technique and powder X-ray diffraction (XRD) Rietveld refinement were combined to characterize the crystal structure of quaternary disordered MgyAl(8+x-2y)/3O4-xNx solid solutions in detail, which was supported by the first-principles density functional theory calculations. Diffraction data indicate that Mg ions preferentially enter the tetrahedron structure in MgyAl(8+x-2y)/3O4-xNx solid solutions because the sum of the bond valence in tetrahedron is closer to the atomic valence of Mg. With the compositional change, the coordination polyhedra in the crystal structure will also adjust the volume according to the changes in lattice parameter, anion parameter, and inversion parameter. In addition, the populations, chemical shifts, and quadrupole coupling constants of Al located in different coordinated environments of the solid solutions were detected through the simulation and integration of 27Al MAS NMR spectra, which were related to the structural parameters by the bond valence method. It turns out that 27Al MAS NMR parameters are highly sensitive to the subtle changes in the local environment of Al caused by the preferential occupation of Mg in the tetrahedron. These results provide deep insights into the crystal structural details of novel spinel materials with multiple disorders.

9.
Fish Physiol Biochem ; 46(5): 1729-1741, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32533395

RESUMEN

To understand the physiological response of estuarine fish to acidification, barramundi (Lates calcarifer) juveniles were exposed to acidified seawater in experimental conditions. The molecular response of barramundi to acidification stress was assessed by RNA-seq analysis. A total of 2188 genes were identified as differential expression genes. The gene ontology classification system and Kyoto Encyclopedia of Genes and Genomes database analysis showed that acidification caused differential expressions of genes and pathways in the gills of barramundi. Acidification had a great influence on the signal transduction pathway in cell process. Furthermore, we detected that numerous unigenes involved in the pathways associated with lipid metabolism, carbohydrate metabolism, amino acid metabolism, glycan biosynthesis and metabolism specific and non-specific immunity were changed. This study indicates that the physiological responses in barramundi especially the immune system and energy allocation correspond to the variation of environmental pH. This study reveals the necessity for assessment of the potential of estuarine fishes to cope with acidification of the environment and the need to develop strategies for fish conservation in coastal areas.


Asunto(s)
Estuarios , Peces/fisiología , Agua de Mar/química , Estrés Fisiológico/genética , Transcripción Genética/fisiología , Adaptación Fisiológica/genética , Animales , Peces/genética , Branquias/citología , Concentración de Iones de Hidrógeno
10.
Fish Shellfish Immunol ; 95: 697-704, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31712130

RESUMEN

This study evaluates the effects of different dietary sources of non-protein energy on growth performance, histological structure, antioxidant status and immune response of barramundi Lates calcarifer. Fish were fed with isoenergetic diets (18 kJ/g) with two types of non-protein energy in the experimental groups and a regular diet was used as the control for 56 days. The specific growth rate and survival of fish were not significantly different between experimental diets. Hepatic histology did not reveal significant differences between dietary treatments at cellular level. The activity of most antioxidant enzymes in the lipid group significantly increased, and the antioxidant capacity in the carbohydrate group was significantly higher than that in other treatments. In the TOR pathway, LST8 homolog (mLST8) expression in the high lipid group was downregulated, and the mechanistic target of rapamycin (mTOR) expression in the high carbohydrate group was downregulated and eIF4E expression was upregulated. The C-reactive protein (CRP) expression in the high lipid and high carbohydrate groups was upregulated. The expression levels of heat shock protein genes in the high lipid group and the high carbohydrate group were significantly downregulated. This study indicates that the lipid diet have less effect in fish immunity but is more suitable as a non-protein ingredient for energy supply for barramundi.


Asunto(s)
Alimentación Animal/análisis , Antioxidantes/metabolismo , Suplementos Dietéticos/análisis , Perciformes/inmunología , Animales , Metabolismo de los Hidratos de Carbono , Grasas de la Dieta/administración & dosificación , Proteínas en la Dieta , Metabolismo Energético , Expresión Génica , Hígado/metabolismo , Perciformes/genética , Perciformes/crecimiento & desarrollo
11.
Entropy (Basel) ; 21(2)2019 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-33266838

RESUMEN

In the study, an equiatomic CoCrNiCuZn high-entropy alloy (HEA) was prepared by mechanical alloying (MA) and the phases, microstructures, and thermal properties of the alloy powder were explored. The results suggest that a solid solution with body-centered cubic (BCC) phase and a crystalline size of 10 nm formed after 60 h of milling. Subsequently, the alloy powder was consolidated by spark plasma sintering (SPS) at different temperatures (600 °C, 700 °C, 800 °C, and 900 °C). Two kinds of face-centered cubic (FCC) phases co-existed in the as-sintered samples. Besides, Vickers hardness and compressive strength of the consolidated alloy sintered at 900 °C were respectively 615 HV and 2121 MPa, indicating excellent mechanical properties.

12.
Inorg Chem ; 57(14): 8390-8395, 2018 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-29953214

RESUMEN

Solid state magic angle spinning nuclear magnetic resonance (NMR) and X-ray diffraction (XRD) were used to investigate the inverse behavior and vacancy disorder in alumina-rich spinel, Mg1- xAl2(1+ x/3)O4 (0 ≤ x ≤ 0.86). Simulation and integration of NMR spectra have been developed for probing the population of Al located in different coordinated environments. Rietveld profile refinements were performed for powder XRD spectra by combining with NMR analysis. With changes in the composition, inversion disorder and cationic vacancies coexisting in tetrahedral and octahedral coordinations fluctuate in amount in the crystal lattice. The coordination polyhedra in the crystal structure can adjust the volume to variations of composition, anion parameter, and inverse parameter. This opens a window to the design and functionalization of spinel materials.

13.
Phys Chem Chem Phys ; 19(33): 22177-22189, 2017 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-28795716

RESUMEN

An empirical model based on the bond valence model has been presented to predict the bulk modulus of crystal materials. The bond bulk modulus, in terms of bond valences and bond length, is introduced to describe the resisting ability of a chemical bond to compression. Both the bond bulk modulus and bond density are proposed to be the most important parameters related to the bulk modulus of crystals. For typical ANB8-N and AmBn type crystals, the calculated bulk modulus is in good agreement with experimental values. For multibond crystal systems, the bulk modulus can be equivalent to an average of the bulk modulus of all constituted binary systems. Applied to spinel, B-C-N, polymorphic AR2O4, and chalcopyrite type multibond compounds, their calculated bulk moduli agree well with the available experimental results. Our bulk modulus model can offer a simple and reliable prediction based on the well-described nature of chemical bonding, which makes it powerful for extensively exploring novel superhard materials with low compressibility, and for interpreting geophysical problems.

14.
Inorg Chem ; 55(21): 11089-11095, 2016 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-27739671

RESUMEN

On the basis of the bond valence model, an empirical hardness estimation of inorganic crystals using a simple formula is presented. A new scale, the resistant force per unit area of chemical bond by bond valence, is proposed to be closely related to the hardness of crystals. For multibond crystal systems, the hardness can be equivalent to an average of the hardness of all binary systems in inorganic crystals. Applied to γ-A3N4 (A = C, Si, Ge) nitride spinels and BC2N compounds, their calculated hardness agrees well with the available experimental results. Our empirical hardness method can offer a simple and reliable hardness prediction resulting from well-described chemical bonding by the bond valence model, which makes it powerful for exploring novel superhard materials.

15.
Inorg Chem ; 55(24): 12930-12937, 2016 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-27989198

RESUMEN

The nuclear magnetic resonance (NMR) technique gives insight into the local information in a crystal structure, while Rietveld refinement of powder X-ray diffraction (PXRD) sketches out the framework of a crystal lattice. In this work, first-principles calculations were combined with the solid-state NMR technique and Rietveld refinement to explore the crystal structure of a disordered aluminum oxynitride (γ-alon). The theoretical NMR parameters (chemical shift, δiso, quadrupolar coupling constants, CQ, and asymmetry parameter, η) of Al22.5O28.5N3.5, predicted by the gauge-including projector augmented wave (GIPAW) algorithm, were used to facilitate the analytical investigation of the 27Al magic-angle spinning (MAS) NMR spectra of the as-prepared sample, whose formula was confirmed to be Al2.811O3.565N0.435 by quantitative analysis. The experimental δiso, CQ, and η of 27Al showed a small discrepancy compared with theoretical models. The ratio of aluminum located at the 8a to 16d sites was calculated to be 0.531 from the relative integration of peaks in the 27Al NMR spectra. The occupancies of aluminum at the 8a and 16d positions were determined through NMR investigations to be 0.9755 and 0.9178, respectively, and were used in the Rietveld refinement to obtain the lattice parameter and anion parameter of Al2.811O3.565N0.435. The results from 27Al NMR investigations and PXRD structural refinement complemented each other. This work provides a powerful and accessible strategy to precisely understand the crystal structure of novel oxynitride materials with multiple disorder.

16.
Phys Chem Chem Phys ; 18(5): 3638-43, 2016 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-26753745

RESUMEN

Ag3PO4 has been proven to be a promising catalyst with superior activity compared to other existing visible-light-driven photocatalysts. In this work, Ag3PO4 nanoparticles were deposited on the surface of two-dimensional Ag2S sheets by an in situ synthesis strategy. The microstructure, composition, and performance of the resulting Ag3PO4/Ag2S composites could be tailored by surface-functioned Ag2S sheets. The composite reached optimum performance when the molar ratio of Ag2S to Ag3PO4 was 0.31, showing a 2-fold enhancement in the degradation rate in comparison to pure Ag3PO4. Efficient separation of photogenerated electron-hole pairs was achieved through a Z-scheme system in which Ag particles served as the center for the combination of electrons at the conduction band of Ag3PO4 and holes at the valence band of Ag2S. In addition to the matched band structure of Ag2S and Ag3PO4, the monodispersed Ag3PO4 nanoparticles were efficient in light harvesting due to the presence of Ag2S. The advantageous interface effect produced by Ag2S sheets and nano-sized Ag3PO4 nanoparticles also contributed to the improvement in photocatalytic activity.

17.
Angew Chem Int Ed Engl ; 55(9): 3031-5, 2016 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-26822893

RESUMEN

Structure-forming processes leading to biominerals are well worth learning in pursuit of new synthetic techniques. Strategies that attempt to mimic nature in vitro cannot replace an entire complex natural organism, requiring ingenuity beyond chemists' hands. A "bioprocess-inspired synthesis" is demonstrated for fabrication of N-doped TiO2 materials at ambient temperature by direct implantation of precursor into living mussels. The amorphous precursor transforms into N-doped anatase TiO2 with a hierarchical nanostructure. Synthetic TiO2 exhibits high phase stability and enhanced visible-light photocatalytic activity as a result of modifications to its band gap during in vivo mineralization. Intracellular proteins were found to be involved in TiO2 mineralization. Our findings may inspire material production by new synthetic techniques, especially under environmentally benign conditions.


Asunto(s)
Bivalvos/metabolismo , Nitrógeno/química , Titanio/química , Animales , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión
18.
Inorg Chem ; 53(12): 5986-92, 2014 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-24871452

RESUMEN

Spinel-type crystals may possess complex and versatile chemical composition and crystal structure, which leads to difficulty in constructing relationships among the chemical composition, crystal structure, and intrinsic properties. In this work, we develop new empirical methods based on bond valences to estimate the intrinsic properties, namely, compressibility and thermal expansion of complex spinel-type crystals. The composition-weighted average of bond force constants in tetrahedral and octahedral coordination polyhedra is derived as a function of the composition-weighted average of bond valences, which can be calculated according to the experimental chemical composition and crystal structural parameters. We discuss the coupled effects of tetrahedral and octahedral frameworks on the aforementioned intrinsic properties. The bulk modulus could be quantitatively calculated from the composition-weighted average of bond force constants in tetrahedral and octahedral coordination polyhedra. In contrast, a quantitative estimation of the thermal expansion coefficient could be obtained from the composition-weighted average of bond force constants in octahedral coordination polyhedra. These empirical methods have been validated by the results obtained for a new complex quaternary spinel-type oxynitride Mg0.268Al2.577O3.733N0.267 as well as MgAl2O4 and Al2.85O3.45N0.55 from the literature. Further, these empirical methods have the potential to be extensively applied in other types of complex crystals.

19.
J Xenobiot ; 14(3): 923-938, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-39051347

RESUMEN

This study examines the physiological and immunological effects of 0.5 ppm carbaryl exposure on juvenile Asian seabass (Lates calcarifer) over 12 h to 72 h. Notable results include decreased activities of liver enzymes catalase (CAT), lactate dehydrogenase (LDH), and glutathione peroxidase (GSH-PX), while superoxide dismutase (SOD) levels remained stable, with the lowest activities of CAT and GSH-PX observed at 72 h. Serum biochemistry revealed increased alkaline phosphatase (AKP) and acid phosphatase (ACP) at 24 h, with declining aspartate aminotransferase (AST) and a peak in creatinine at 48 h. Histopathological analysis showed carbaryl-induced necrosis in liver and spleen cells, and increased melanomacrophage centers in both organs. Additionally, immune gene expression analysis indicated an upregulation of heat shock proteins and consistent elevation of complement component C3 and interleukin-8 (IL-8). These findings suggest that carbaryl exposure significantly impairs organ function and modulates immune responses in L. calcarifer, underlining the need for further research on protective strategies against pesticide impacts in aquaculture.

20.
Heliyon ; 10(8): e29205, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38638986

RESUMEN

Spotted babylon were exposed to three different pH levels (7.0, 8.0 and 9.0) and four different concentrations of ammonia nitrogen (0.02, 1.02, 5.10 and 10.20 mg/L) in seawater to determine their acute toxicity and physiological responses to environmental fluctuation. The study evaluated four antioxidant enzymes: catalase (CAT), alkaline, superoxide dismutase (SOD), peroxidase (POD) and glutathione peroxidase (GSH-PX), and two immunoenzymes: acid phosphatase (ACP) and phosphatase (AKP). Over time, the immunoenzyme activity was significantly affected by pH and ammonia nitrogen concentration. After being exposed to pH and ammonia nitrogen, the spotted babylon showed signs of unresponsiveness to external stimuli, reduced vitality, slow movement, and an inability to maintain an upright position. Over time, the spotted babylon exhibited a trend of increasing and then decreasing GSH-PX, CAT, and SOD activities to adapt to the changing environment and enhance its immunity. On the contrary, the POD and ACP activities exhibited a decreasing trend initially, followed by an increasing trend over time and the AKP activity showed a gradual increase with time. The combined effect of pH and ammonia was found to be stronger than the effect of either factor alone. The interaction between pH and ammonia increased the activity of the spotted babylon antioxidant enzymes, induced oxidative stress, and reduced the ability of the spotted babylon's non-specific immune system to reverse it. Thus, the reverse-back of the spotted babylon was higher when pH and ammonia stress were dual than when pH or ammonia were single-factor stresses. The study results will establish a theoretical basis for analyzing the risk of multiple factors to the spotted babylon, and also enrich the basic information about the shellfish immune system.

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