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The contamination of water by arsenic (As) has emerged as a significant environmental concern due to its well-documented toxicity. Environmentally relevant concentrations of As have been reported to pose a considerable threat to fish. However, previous studies mainly focused on the impacts of As at environmentally relevant concentrations on adult fish, and limited information is available regarding its impacts on fish at early life stage. In this study, zebrafish embryos were employed to evaluate the environmental risks following exposure to different concentrations (0, 25, 50, 75 and 150⯵g/L) of pentavalent arsenate (AsV) for 120â¯hours post fertilization. Our findings indicated that concentrations ≤ 150⯵g/L AsV did not exert significant effects on survival or aberration; however, it conspicuously inhibited heart rate of zebrafish larvae. Furthermore, exposure to AsV significantly disrupted mRNA transcription of genes associated with cardiac development, and elongated the distance between the sinus venosus and bulbus arteriosus at 75⯵g/L and 150⯵g/L treatments. Additionally, AsV exposure enhanced superoxide dismutase (SOD) activity at 50, 75 and 150⯵g/L treatments, and increased mRNA transcriptional levels of Cu/ZnSOD and MnSOD at 75 and 150⯵g/L treatments. Concurrently, AsV suppressed metallothionein1 (MT1) and MT2 mRNA transcriptions while elevating heat shock protein70 mRNA transcription levels in zebrafish larvae resulting in elevated malondialdehyde (MDA) levels. These findings provide novel insights into the toxic effects exerted by low concentrations of AsV on fish at early life stage, thereby contributing to an exploration into the environmental risks associated with environmentally relevant concentrations.
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Arseniatos , Embrión no Mamífero , Corazón , Estrés Oxidativo , Contaminantes Químicos del Agua , Pez Cebra , Animales , Arseniatos/toxicidad , Contaminantes Químicos del Agua/toxicidad , Estrés Oxidativo/efectos de los fármacos , Embrión no Mamífero/efectos de los fármacos , Corazón/efectos de los fármacos , Superóxido Dismutasa/metabolismo , Metalotioneína/metabolismo , Metalotioneína/genética , Larva/efectos de los fármacos , Frecuencia Cardíaca/efectos de los fármacos , Relación Dosis-Respuesta a DrogaAsunto(s)
Conductos Biliares Intrahepáticos , Humanos , Conductos Biliares Intrahepáticos/patología , Conductos Biliares Intrahepáticos/diagnóstico por imagen , Dilatación Patológica , Masculino , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/cirugía , Neoplasias de los Conductos Biliares/patología , Neoplasias de los Conductos Biliares/cirugía , Femenino , Persona de Mediana EdadRESUMEN
Conventional hemostatic agents face challenges in achieving rapid hemostasis and effective tissue repair due to limited hemostatic scenarios, suboptimal efficacy, and inadequate adhesion to wet tissues. Drawing inspiration from nature-sourced materials, a gelatin-based adhesive hydrogel (AOT) is designed, easily prepared and quick to form, driven by Schiff base and multiple hydrogen bonds for applications in arterial and liver bleeding models. AOT exhibits exceptional adhesion to wet tissues (48.67 ± 0.16 kPa) and displays superior hemostatic properties with reduced blood loss and hemostatic time compared to other hydrogels and conventional hemostatic materials. Moreover, AOT exhibits good biocompatibility and biodegradability. In summary, this easily prepared adhesive hydrogel has the potential to supplant traditional hemostatic agents, offering a novel approach to achieve swift sealing of hemostasis and facilitate wound healing and repair in broader application scenarios, owing to its unique advantages.
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Gelatina , Hemostasis , Hemostáticos , Hidrogeles , Gelatina/química , Hidrogeles/química , Hidrogeles/farmacología , Animales , Hemostáticos/química , Hemostáticos/farmacología , Hemostasis/efectos de los fármacos , Ratones , Hemorragia , Cicatrización de Heridas/efectos de los fármacos , Ratas , Humanos , Adhesivos/química , Adhesivos/farmacología , Masculino , HígadoRESUMEN
3-bromine carbazole (3-BCZ) represents a group of emerging aromatic disinfection byproducts (DBP) detected in drinking water; however, limited information is available regarding its potential cardiotoxicity. To assess its impacts, zebrafish embryos were exposed to 0, 0.06, 0.14, 0.29, 0.58, 1.44 or 2.88 mg/L of 3-BCZ for 120 h post fertilization (hpf). Our results revealed that ≥1.44 mg/L 3-BCZ exposure induced a higher incidence of heart malformation and an elevated pericardial area in zebrafish larvae; it also decreased the number of cardiac muscle cells and thins the walls of the ventricle and atrium while increasing cardiac output and impeding cardiac looping. Furthermore, 3-BCZ exposure also exhibited significant effects on the transcriptional levels of genes related to both cardiac development (nkx2.5, vmhc, gata4, tbx5, tbx2b, bmp4, bmp10, and bmp2b) and cardiac function (cacna1ab, cacna1da, atp2a1l, atp1b2b, atp1a3b, and tnnc1a). Notably, N-acetyl-L-cysteine, a reactive oxygen species scavenger, may alleviate the failure of cardiac looping induced by 3-BCZ but not the associated cardiac dysfunction or malformation; conversely, the aryl hydrocarbon receptor agonist CH131229 can completely eliminate the cardiotoxicity caused by 3-BCZ. This study provides new evidence for potential risks associated with ingesting 3-BCZ as well as revealing underlying mechanisms responsible for its cardiotoxic effects on zebrafish embryos.
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Proteínas de Pez Cebra , Pez Cebra , Animales , Proteínas de Pez Cebra/genética , Corazón , Bromo/farmacología , Cardiotoxicidad , Receptores de Hidrocarburo de Aril/genética , Larva , Desinfección , Embrión no MamíferoRESUMEN
Cucurbit[n]urils (Q[n]s) are a class of supramolecular host compounds with hydrophilic carbonyl ports and hydrophobic cavities, which can selectively form host-guest inclusion complexes with guest molecules to change the properties of guest molecules. In this paper, tetramethyl cucurbit[6]uril (TMeQ[6]) was used as the host and three 2-heterocyclic substituted benzimidazole derivatives as the guests, and their modes of interaction were investigated using X-ray crystallography, 1H NMR spectrometry, and other analytical techniques. The results showed that TMeQ[6] formed a 1 : 1 host-guest inclusion complex with three guest molecules, and the binding process between them was mainly enthalpy-driven. The X-ray diffraction analysis indicated that the main driving forces for the formation of these three inclusion complexes included hydrogen bonding interactions and ion dipole interactions. There are two modes of interaction between G3 and TMeQ[6] in the liquid phase, indicating that the benzimidazole ring and heterocyclic substituents on the guest molecule compete with the cavity of TMeQ[6]. Besides, the addition of TMeQ[6] significantly enhanced the fluorescence of these guests and slightly improved their solubility.
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Solar-driven water purification has been deemed a promising technology to address the issue of clean water scarcity. However, traditional solar distillers often suffer from low evaporation rates under natural sunlight irradiation, while the high costs of the fabrication of photothermal materials further hinders their practical applications. Here, through the harnessing of the complexation process of oppositely charged polyelectrolyte solutions, a polyion complex hydrogel/coal powder composite (HCC)-based highly efficient solar distiller is reported. In particular, the influence of the charge ratio of polyanion-to-polycation on the solar vapor generation performance of HCC has been systematically investigated. Together with a scanning electron microscope (SEM) and the Raman spectrum method, it is found that a deviation from the charge balance point not only alters the microporous structure of HCC and weakens its water transporting capabilities, but also leads to a decreased content of activated water molecules and enlarges the energy barrier of water evaporation. As a result, HCC prepared at the charge balance point exhibits the highest evaporation rate of 3.12 kg m-2 h-1 under one sun irradiation, with a solar-vapor conversion efficiency as high as 88.83%. HCC also exhibits remarkable solar vapor generation (SVG) performance for the purification of various water bodies. In simulated seawater (3.5 wt% NaCl solutions), the evaporation rate can be as high as 3.22 kg m-2 h-1. In acid and alkaline solutions, HCCs are capable of maintaining high evaporation rates of 2.98 and 2.85 kg m-2 h-1, respectively. It is anticipated that this study may provide insights for the design of low-cost next-generation solar evaporators, and broaden the practical applications of SVG for seawater desalination and industrial wastewater purification.
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Biological soft tissues are intrinsically viscoelastic materials which play a significant role in affecting the activity of cells. As potential artificial alternatives, double-network (DN) gels, however, are pure elastic and mechanically time independent. The viscoelasticization of DN gels is an urgent challenge in enabling DN gels to be used for advanced development of biomaterial applications. Herein, we demonstrate a simple approach to regulate the viscoelasticity of tough double-network (DN) hydrogels by forming sulfonate-metal coordination. Owing to the dynamic nature of the coordination bonds, the resultant hydrogels possess highly viscoelastic, mechanical time-dependent, and self-recovery properties. Rheological measurements are performed to investigate the linear dynamic mechanical behavior at small strains. The tensile tests and cyclic tensile tests are also systematically performed to evaluate the rate-dependent large deformation mechanical behaviors and energy dissipation behaviors of various ion-loaded DN hydrogels. It has been revealed based on the systematic analysis that robust strong sulfonate-Zr4+ coordination interactions not only serve as dynamic crosslinks imparting viscoelastic rate-dependent mechanical performances, but also strongly affect the relative strength of the first PAMPS network, thereby increasing the yielding stress σy and the fracture stress at break σb and reducing the stretch ratio at break λb. It is envisioned that the viscoelasticization of DN gels enables versatile applications in the biomedical and engineering fields.
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The Kirigami approach is an effective way to realize controllable deformation of intelligent materials via introducing cuts into bulk materials. For materials ranging from ordinary stiff materials such as glass, ceramics, and metals to soft materials, including ordinary hydrogels and elastomers, all of them are all sensitive to the presence of cuts, which usually act as defects to deteriorate mechanical properties. Herein, we study the influence of the cuts on the mechanical properties by introducing "dispersed macro-scale cuts" into a model tough double network (DN) hydrogel (named D-cut gel), which consists of a rigid and brittle first network and a ductile stretchable second network. For comparison, DN gels with "continuous cuts" having the same number of interconnected cuts (named C-cut gel) were chosen. The fracture tests of D-cut gel and C-cut gel with different cut patterns were performed. The fracture observation revealed that crack blunting occurred at each cut tip, and a large wrinkle-like zone was formed where the wrinkles were parallel to the propagation direction of the cut. By utilizing homemade circular polarizing optical systems, we found that introducing dispersed cuts increases the rupture force by homogenizing the stress around the crack tip surrounding every cut, which reduces stress concentration in one certain cut. We believe this work reveals the fracture mechanism of tough soft materials with a kirigami cut structure, which should guide the design of advanced soft and tough materials along this line.
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Hydrogels with ultrafast response to environmental stimuli, possessing robust structural integrity and rapid self-recovery, have been considered as promising platforms for numerous applications, for example, in biomimetic materials and nanomedicine. Inspired by the bundled fibrous structure of actin, we developed a robust and ultrafast thermoresponsive fibrous hydrogel (TFH) by fully utilizing the weak noncovalent bonds and strong covalently cross-linked semiflexible electrospun fibrous nets. The TFH exhibits an ultrafast response (within 10 s), rapid self-recovery rate (74% within 10 s), tunable tensile strength (3-380 kPa), and high toughness (â¼1560 J/m2) toward temperature. A multiscale orientation is considered to play a key role in the excellent mechanical properties at the fibrous mesh, fiber, and molecular scales. Furthermore, to take advantage of this TFH adequately, a novel kind of noodle-like hydrogel for thermo-controlled protein sorption based on the TFH is prepared, which exhibits high stability and ultrafast sorption properties. The bioinspired platforms hold promise as artificial skins and "smart" sorption membrane carriers, which provide a unique bioactive environment for tissue engineering and nanomedicine.
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Materiales Biomiméticos/química , Hidrogeles/química , Temperatura , Agua/química , Estructura Molecular , Resistencia a la TracciónRESUMEN
Quantitative predictions of FtsZ protein polymerization are essential for understanding the self-regulating mechanisms in biochemical systems. Due to structural complexity and parametric uncertainty, existing kinetic models remain incomplete and their predictions error-prone. To address such challenges, we perform probabilistic uncertainty quantification and global sensitivity analysis of the concentrations of various protein species predicted with a recent FtsZ protein polymerization model. Our results yield a ranked list of modeling shortcomings that can be improved in order to develop more accurate predictions and more realistic representations of key mechanisms of such biochemical systems and their response to changes in internal or external conditions. Our conclusions and improvement recommendations can be extended to other kinetics models.