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BACKGROUND: A loss-of-function cardiac ryanodine receptor (RyR2) mutation, I4855M+/-, has recently been linked to a new cardiac disorder termed RyR2 Ca2+ release deficiency syndrome (CRDS) as well as left ventricular noncompaction (LVNC). The mechanism by which RyR2 loss-of-function causes CRDS has been extensively studied, but the mechanism underlying RyR2 loss-of-function-associated LVNC is unknown. Here, we determined the impact of a CRDS-LVNC-associated RyR2-I4855M+/- loss-of-function mutation on cardiac structure and function. METHODS: We generated a mouse model expressing the CRDS-LVNC-associated RyR2-I4855M+/- mutation. Histological analysis, echocardiography, ECG recording, and intact heart Ca2+ imaging were performed to characterize the structural and functional consequences of the RyR2-I4855M+/- mutation. RESULTS: As in humans, RyR2-I4855M+/- mice displayed LVNC characterized by cardiac hypertrabeculation and noncompaction. RyR2-I4855M+/- mice were highly susceptible to electrical stimulation-induced ventricular arrhythmias but protected from stress-induced ventricular arrhythmias. Unexpectedly, the RyR2-I4855M+/- mutation increased the peak Ca2+ transient but did not alter the L-type Ca2+ current, suggesting an increase in Ca2+-induced Ca2+ release gain. The RyR2-I4855M+/- mutation abolished sarcoplasmic reticulum store overload-induced Ca2+ release or Ca2+ leak, elevated sarcoplasmic reticulum Ca2+ load, prolonged Ca2+ transient decay, and elevated end-diastolic Ca2+ level upon rapid pacing. Immunoblotting revealed increased level of phosphorylated CaMKII (Ca2+-calmodulin dependent protein kinases II) but unchanged levels of CaMKII, calcineurin, and other Ca2+ handling proteins in the RyR2-I4855M+/- mutant compared with wild type. CONCLUSIONS: The RyR2-I4855M+/- mutant mice represent the first RyR2-associated LVNC animal model that recapitulates the CRDS-LVNC overlapping phenotype in humans. The RyR2-I4855M+/- mutation increases the peak Ca2+ transient by increasing the Ca2+-induced Ca2+ release gain and the end-diastolic Ca2+ level by prolonging Ca2+ transient decay. Our data suggest that the increased peak-systolic and end-diastolic Ca2+ levels may underlie RyR2-associated LVNC.
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Cardiopatías Congénitas , Canal Liberador de Calcio Receptor de Rianodina , Animales , Humanos , Ratones , Arritmias Cardíacas/metabolismo , Calcio/metabolismo , Señalización del Calcio/fisiología , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/metabolismo , Cardiopatías Congénitas/metabolismo , Miocitos Cardíacos/metabolismo , Canal Liberador de Calcio Receptor de Rianodina/genética , Canal Liberador de Calcio Receptor de Rianodina/metabolismo , Retículo Sarcoplasmático/metabolismoRESUMEN
2D perovskites have attracted tremendous attention due to their superior optoelectronic properties and potential applications in optoelectronic devices. Especially, the larger bandgap of 2D perovskite means that they are suitable for UV photodetection. However, the layered structure of 2D perovskites hinders the interlayer carrier transport, which limits the improvement of device performance. Therefore, nanoscale structures are normally used to enhance the light absorption ability, which is an effective strategy to improve the photocurrent in 2D perovskite-based photodetectors. Herein, a template-assisted low-temperature method is proposed to fabricate 2D perovskite ((C6H5C2H4NH3)2PbBr4, (PEA)2PbBr4) grating single crystal films (GSCFs). The crystallinity of the (PEA)2PbBr4 GSCFs is significantly improved due to the slow evaporation of the precursor solution under low temperatures. Based on this high crystalline quality and extremely ordered microstructures, the metal-semiconductor-metal photodetectors are assembled. Finite-different time-domain (FDTD) simulation and experiment indicate that the GSCF-based photodetectors exhibit significantly improved performance in comparison with the plane devices. The optimized 2D perovskite photodetectors are sensitive to UV light and demonstrate a responsivity and detectivity of 28.6 mA W-1 and 2.4 × 1011 Jones, respectively. Interestingly, the photocurrent of this photodetector varies as the angle of the incident polarized light, resulting in a high polarization ratio of 1.12.
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Amid rapid advancements in aerospace science and technology, studying the effects of space radiation on an infrared detector is crucial for enhancing their reliability in radiation environments, particularly against electrons-one of the most damaging charged particles. Barrier structures significantly reduce dark current without any substantial degradation in the optical performance of the devices. Consequently, they are being investigated for use in extreme environments. This paper presents a study on the performance degradation of InAs/GaSb type II superlattice (T2SLs) long-wave infrared (LWIR) detectors with a graded barrier structure under 1â MeV electron irradiation and analyzes potential damage mechanisms. The findings indicate that 1â MeV electron irradiation causes both ionization and displacement damage to the graded barrier InAs/GaSb T2SL LWIR detectors. After irradiation with a fluence of 2 × 1015â e/cm2, the device's dark current density has increased by approximately two orders of magnitude, while the quantum efficiency has decreased by approximately one order of magnitude. As the device mesa shrinks, the sensitivity of dark current to radiation exposure increases. Electron irradiation notably exacerbates surface leakage and bulk dark current, with a pronounced increase in surface leakage current. The study also reveals that electron irradiation primarily enhances the dark current by introducing defect states, thereby leading to device performance degradation.
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Poly(amino acid)s (PAAs) are one kind of favorable biopolymer that can be used as a drug or gene carrier. However, conventional ring-opening polymerization of PAAs is slow and needs a strict anhydrous environment with an anhydrous reagent as well as the product without enough high molecular weight (Mn), which limits the expanding of PAAs' application. Herein, we took BLG-NCA as the monomer to quickly synthesize one kind of high Mn amphiphilic copolymer, poly(ethylene glycol)-b-poly(γ-benzyl-l-glutamic acid) (PEG-PBLG), by relay polymerization with a simple one-pot method within 3 h in mild conditions (open air, moisture insensitive). In the polymerization process, ring-opening polymerization-induced self-assembly in sodium bicarbonate aqueous solution first occurred to obtain low Mn PEG-PBLG seeds without purification. Then γ-benzyl-l-glutamate N-carboxyanhydride (BLG-NCA) dichloromethane solution was added into PEG-PBLG seeds directly and stirred vigorously to form am emulsion; during this process, the amphiphilic PEG-PBLG seeds will anchor on the interface of DCM and water to ensure the concentration of α-helix rigid PBLG in DCM to maintain the following relay polymerization. Then, high Mn PEG-PBLG was obtained in mild conditions in one pot. We found that the α-helix rigid structure was essential for relay polymerization by studying the synthetic speed of amphiphilic copolymer with different secondary structures. MOE simulation results showed that PBLG and BLG-NCA tended to form a double hydrogen bond, which was beneficial to relay polymerization because of higher local concentrations that can produce more double hydrogen bonds. Our strategy can quickly obtain high Mn PEG-PBLG (224.9 KDa) within 3 h from PEG-NH2 and BLG-NCA in one pot and did not need an extra initiator. After deprotection, the poly(ethylene glycol)-b-poly(l-glutamate acid) (PEG-PGA) with high Mn as a second product can be used as an excellent antitumor drug carrier. The high Mn PEG-PGA can achieve an encapsulation rate of 86.7% and a drug loading rate of 47.3%, which is twice that of the low Mn PEG-PGA. As a result, the synthesis of PEG-PBLG by relay polymerization simplified the process of PEG-PAA polymerization and increased the Mn. In addition, this method opened a way to obtain other kinds of high Mn PEG-PBLG values in the future.
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Aminoácidos , Anhídridos , Glutamatos , Polietilenglicoles , Polietilenglicoles/química , Aminoácidos/química , Polimerizacion , Ácido Glutámico , Peso Molecular , Polímeros/química , Ácido Poliglutámico/químicaRESUMEN
Supercritical water oxidation (SCWO) has been regarded as a new and efficient technology for the harmless treatment and energy utilization of organic wastes, resulting in the quickly homogeneous oxidation between organics and oxidizers and the former being wholly degraded into small environment-friendly green molecules such as H2O and N2 and inorganic salts. This paper systematically analyzed the influencing behavior and mechanisms of the reaction factors, such as temperature, pressure, residence time, oxidant type, oxidation coefficient, and the concentration and pH values of the raw material, on the treatment effect of organic wastes. For most organic wastes, the SCWO conditions at 550 °C with a residence time of 1min and an oxidation coefficient of 100% can meet the removal rate of more than 99%. To further enhance the degradation rate of organics, the principles, implementation cases, and related equipment components of general enhancement technologies of supercritical water oxidation were discussed, such as fractional oxygen injection, auxiliary fuel co-oxidation, and hydrothermal flame-assisted degradation. This paper proposes a novel supercritical flame-assisted oxidation process in which the reactor performs preheating, corrosion protection, and desalination functions. The use of additive-enhanced oxidation, segmented oxidation, and supercritical hydrothermal flame-assisted oxidation has achieved good results in the complicated treatment process of brutal degradation of organic matter.
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Oxidación-Reducción , Agua , Agua/química , Compuestos Orgánicos/química , Eliminación de Residuos Líquidos/métodos , TemperaturaRESUMEN
BACKGROUND: Ureaplasma urealyticum (U. urealyticum) commonly occurs in female genitourinary infections, and its different biovars and serotypes have varying degrees of resistance to different antibiotics. This study aimed to ex-plore the characteristics of U. urealyticum infection and drug-resistant profiles in Chinese females. METHODS: We included 1,045 females with genital tract infections who visited Tangshan Workers' Hospital and Tangshan Maternal and Child Health Center from September 2017 to December 2018. The bacteria were selectively cultured, and drug sensitivity experiments were conducted. Eight pairs of oligonucleotide primers were designed, and polymerase chain reaction (PCR) was performed to amplify specific DNA fragments to perform bacterial strain typing. RESULTS: Among the 1,045 participants included, 566 (54.11%) participants were positive for mycoplasma infection. There were 432 (41.34%) participants with U. urealyticum infection, accounting for 76.33% of the positive participants. The infection rate of U. urealyticum was the highest in females who were 21 - 30 years old, followed by those who were 31 - 40 years old. Ureaplasma urealyticum showed the highest sensitivity to tetracyclines and the greatest resistance to quinolones. The biovar 1 of U. urealyticum with the highest detection rate of serotype 4, accounted for 66.88%. The biovar 2 of U. urealyticum mainly showed mixed subtypes 2 and 3. Biovar 2 showed higher resistance to sparfloxacin, clarithromycin, josamycin, and doxycycline than biovar 1. CONCLUSIONS: Women might be more susceptible to U. urealyticum, especially if they are of childbearing age. Urea-plasma urealyticum is mainly caused by a single serotype 6 infection. The resistance of U. urealyticum to quinolone (e.g., norfloxacin) is a great concern. Sparfloxacin, clarithromycin, ciprofloxacin, and doxycycline might be more suitable for people with biovar 1 infection. Biotyping may facilitate clinical drug use and help avoid the emergence of drug-resistant strains.
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Doxiciclina , Ureaplasma urealyticum , Niño , Humanos , Femenino , Adulto Joven , Adulto , Ureaplasma urealyticum/genética , Claritromicina , Pruebas de Sensibilidad Microbiana , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Genitales Femeninos , Resistencia a MedicamentosRESUMEN
Bacterial diseases are one of the most common issues that result in crop loss worldwide, and the increasing usage of chemical pesticides has caused the occurrence of resistance in pathogenic bacteria and environmental pollution problems. Nanomaterial mediated gene silencing is starting to display powerful efficiency and environmental friendliness for improving plant disease resistance. However, the internalization of nanomaterials and the physiological mechanisms behind nano-improved plant disease resistance are still rarely understood. We engineered the polyethyleneimine (PEI) functionalized gold nanoparticles (PEI-AuNPs) with fluorescent properties and ROS scavenging activity to act as siRNA delivery platforms. Besides the loading, protection, and delivery of nucleic acid molecules in plant mature leaf cells by PEI-AuNPs, its fluorescent property further enables the traceability of the distribution of the loaded nucleic acid molecules in cells. Additionally, the PEI-AuNPs-based RNAi delivery system successfully mediated the silencing of defense-regulated gene AtWRKY1. Compared to control plants, the silenced plants performed better resistance to Pseudomonas syringae, showing a reduced bacterial number, decreased ROS content, increased antioxidant enzyme activities, and improved chlorophyll fluorescence performance. Our results showed the advantages of AuNP-based RNAi technology in improving plant disease resistance, as well as the potential of plant nanobiotechnology to protect agricultural production.
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Resistencia a la Enfermedad , Oro , Nanopartículas del Metal , Enfermedades de las Plantas , Pseudomonas syringae , ARN Interferente Pequeño , Especies Reactivas de Oxígeno , Oro/química , Nanopartículas del Metal/química , Especies Reactivas de Oxígeno/metabolismo , Enfermedades de las Plantas/microbiología , Polietileneimina/química , Silenciador del Gen , Arabidopsis/genéticaRESUMEN
Arrayed libraries of defined mutants have been used to elucidate gene function in the post-genomic era. Yeast haploid gene deletion libraries have pioneered this effort, but are costly to construct, do not reveal phenotypes that may occur with partial gene function and lack essential genes required for growth. We therefore devised an efficient method to construct a library of barcoded insertion mutants with a wider range of phenotypes that can be generalized to other organisms or collections of DNA samples. We developed a novel but simple three-dimensional pooling and multiplexed sequencing approach that leveraged sequence information to reduce the number of required sequencing reactions by orders of magnitude, and were able to identify the barcode sequences and DNA insertion sites of 4391 Schizosaccharomyces pombe insertion mutations with only 40 sequencing preparations. The insertion mutations are in the genes and untranslated regions of nonessential, essential and noncoding RNA genes, and produced a wider range of phenotypes compared to the cognate deletion mutants, including novel phenotypes. This mutant library represents both a proof of principle for an efficient method to produce novel mutant libraries and a valuable resource for the S. pombe research community.
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Schizosaccharomyces , ADN , Elementos Transponibles de ADN/genética , Biblioteca de Genes , Genes Esenciales , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Mutagénesis Insercional , ARN no Traducido , Saccharomyces cerevisiae/genética , Schizosaccharomyces/genética , Regiones no TraducidasRESUMEN
As a means to aid in the investigation of viral infection mechanisms and identification of more effective antivirus targets, the availability of a source which continually collects and updates information on the virus and host ncRNA-associated interaction resources is essential. Here, we update the ViRBase database to version 3.0 (http://www.virbase.org/ or http://www.rna-society.org/virbase/). This update represents a major revision: (i) the total number of interaction entries is now greater than 820,000, an approximately 70-fold increment, involving 116 virus and 36 host organisms, (ii) it supplements and provides more details on RNA annotations (including RNA editing, RNA localization and RNA modification), ncRNA SNP and ncRNA-drug related information and (iii) it provides two additional tools for predicting binding sites (IntaRNA and PRIdictor), a visual plug-in to display interactions and a website which is optimized for more practical and user-friendly operation. Overall, ViRBase v3.0 provides a more comprehensive resource for virus and host ncRNA-associated interactions enabling researchers a more effective means for investigation of viral infections.
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Bases de Datos Genéticas , Genoma Viral , Interacciones Huésped-Patógeno/genética , ARN no Traducido/genética , Programas Informáticos , Virus/genética , Sitios de Unión , Cromatina/química , Cromatina/metabolismo , Humanos , Internet , Anotación de Secuencia Molecular , Polimorfismo de Nucleótido Simple , Edición de ARN , ARN no Traducido/clasificación , ARN no Traducido/metabolismo , Transducción de Señal , Virosis/genética , Virosis/metabolismo , Virosis/patología , Virosis/virología , Virus/clasificación , Virus/metabolismo , Virus/patogenicidadRESUMEN
BACKGROUND: Arterial injury caused by heterotopic ossification (HO) following fractures is rarely reported, yet it can have catastrophic consequences. This case report presents a unique instance of femoral artery injury and hematoma organization, occurring a decade after intramedullary nail fixation for a femoral shaft fracture complicated by HO. CASE PRESENTATION: A 56-year-old male presented with right femoral artery injury and organized hematoma, a decade after suffering bilateral femoral shaft fractures with mild head injury in a traffic accident. He had received intramedullary nailing for the right femoral shaft fracture and plate fixation for the left side in a local hospital. Physical examination revealed two firm, palpable masses with clear boundaries, limited mobility, and no tenderness. Peripheral arterial pulses were intact. Radiography demonstrated satisfactory fracture healing, while a continuous high-density shadow was evident along the inner and posterior aspect of the right thigh. Computed tomography angiography identified a large mixed-density mass (16.8 × 14.8 × 20.7 cm) on the right thigh's medial side, featuring central calcification and multiple internal calcifications. The right deep femoral artery coursed within this mass, with a smaller lesion noted on the posterior thigh. Surgical consultation with a vascular surgeon led to planned intervention. The smaller mass was completely excised, but the larger one partially, as it encased the femoral artery. The inability to remove all HO was due to excessive bleeding. Postoperatively, the patient experienced no complications, and one-year follow-up revealed a favorable recovery with restoration of full right lower limb mobility. CONCLUSION: This case underscores the potential gravity of vascular injury associated with heterotopic ossification. Surgeons should remain vigilant regarding the risk of vascular injury during HO excision.
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Arteria Femoral , Fracturas del Fémur , Osificación Heterotópica , Humanos , Osificación Heterotópica/cirugía , Osificación Heterotópica/etiología , Osificación Heterotópica/diagnóstico por imagen , Osificación Heterotópica/complicaciones , Masculino , Arteria Femoral/cirugía , Arteria Femoral/lesiones , Arteria Femoral/diagnóstico por imagen , Persona de Mediana Edad , Fracturas del Fémur/cirugía , Fracturas del Fémur/etiología , Fracturas del Fémur/diagnóstico por imagen , Fracturas del Fémur/complicaciones , Fijación Intramedular de Fracturas , Lesiones del Sistema Vascular/etiología , Lesiones del Sistema Vascular/cirugía , Lesiones del Sistema Vascular/diagnóstico por imagen , Hematoma/etiología , Hematoma/cirugía , Hematoma/diagnóstico por imagen , Angiografía por Tomografía ComputarizadaRESUMEN
OBJECTIVE: Ferritin heavy chain 1 (FTH1) is an important subunit of ferro-storing proteins and is indispensable for iron metabolism. Though it has been extensively studied in numerous organs and diseases, the relationship between FTH1 and osteoarthritis (OA) is unclear. DESIGN: Primary murine chondrocytes and cartilage explants were treated with FTH1 siRNA for 72 h. Mice were injected with adenovirus expressing FTH1 after destabilized medial meniscus (DMM) surgery. These approaches were used to determine the effect of FTH1 expression on the pathophysiology of OA. RESULTS: FTH1 expression was down regulated in OA patients and mice after DMM surgery. Knock down of FTH1 induced articular cartilage damage and extracellular matrix degradation in cartilage explants. Further, over expression of FTH1 reduced the susceptibility of chondrocytes to ferroptosis and reversed decrements in SOX9 and aggrecan after DMM surgery. Moreover, FTH1 relieved OA by inhibition of the chondrocyte MAPK pathway. CONCLUSION: This study found FTH1 to play an essential role in extracellular matrix degradation, ferroptosis, and chondrocytes senescence during OA progression. Further, injection of adenovirus expressing FTH1 may be a potential strategy for OA prevention and therapy.
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Osteoartritis , Animales , Humanos , Ratones , Adenoviridae/genética , Agrecanos , Condrocitos , Matriz Extracelular , Ferritinas , Osteoartritis/genética , OxidorreductasasRESUMEN
OBJECTIVE: To compare ocular surface parameters in dogs with different cephalic conformations and evaluate correlations among tests. ANIMALS STUDIED: Sixty-eight privately owned dogs. PROCEDURES: The study categorized canine eyes into three groups based on the craniofacial ratio (CFR): brachycephaly (≤0.52), mesocephaly (>0.52 to <0.67), and dolichocephaly (≥0.67). All eyes were examined using an ocular surface analyzer (OSA-VET) to determine lipid layer thickness (LLT) of the tear film, tear meniscus height (TMH), non-invasive tear breakup time (NIBUT), and meibomian gland loss rate of the lower eyelids (MGLRL). Schirmer tear test 1 (STT-1) and tear film breakup time (TBUT) were also performed. Statistical analyses involved one-way ANOVA, Kruskal-Wallis H test, post hoc Holm-Sidak test, and Pearson correlation coefficient. RESULTS: While STT-1 showed no significant difference among dog groups, brachycephalic dogs had significantly lower values in TBUT, NIBUT, and LLT, and a higher TMH, compared to mesocephalic and dolichocephalic dogs. Additionally, brachycephalic dogs exhibited a significantly higher MGLRL than dolichocephalic dogs. Correlations among tests were generally weak to moderate (r < .6) except for a strong correlation between CFR and LLT (r = .641, p < .001), and between TBUT and NIBUT (r = .899, p < .001). CONCLUSIONS: Brachycephalic morphology predisposes dogs to a significantly thinner lipid layer and diminished tear film stability, likely due to factors such as impaired meibomian gland function and increased ocular exposure compared to other cephalic conformations, thereby increasing their risk of keratoconjunctivitis sicca (KCS). OSA-VET shows a valuable tool to provide more comprehensive and precise diagnosis for canine ocular surface disorders.
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BACKGROUND: Poly-D, L-lactic acid (PDLLA) is increasingly used as a commercial dermal filler due to its lasting cosmetic properties. Consequently, PDLLA-related vascular complications are increasingly recognized and described. Herein, we describe the first known occurrence of multifocal strokes from the use of PDLLA as a cosmetic dermal filler, and discuss the mechanisms facilitating PDLLA's entry into the intracranial arterial system. CASE PRESENTATION: A middle-aged female presented with acute vision loss of both eyes immediately after dermal injections of PDLLA to her nasolabial folds and infraorbital regions. There were no additional neurological deficits. Dilated fundal examination revealed retinal edema bilaterally, with deposition of filler material in the retinal arteries. Magnetic resonance imaging of her brain and orbits demonstrated multifocal strokes (left caudate head, right medial frontal lobe) and ischemia of the left optic nerve. The temporal proximity of the dermal injections to her symptoms, guided by fundal examination and neuroimaging findings, allowed us to attribute her strokes and ischemic optic neuropathy to PDLLA's entry into, and embolism within, the intracranial arterial system. She was treated with hyperbaric oxygen therapy and experience improvement to her right eye's vision, although poor vision persisted in her left eye. CONCLUSION: While PDLLA is generally considered safe, its increasing use as a cosmetic filler renders it crucial for physicians to be cognizant of its vascular complications, especially when early recognition and treatment are essential in mitigating their devastating ramifications.
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Técnicas Cosméticas , Rellenos Dérmicos , Accidente Cerebrovascular , Humanos , Persona de Mediana Edad , Femenino , Rellenos Dérmicos/efectos adversos , Técnicas Cosméticas/efectos adversos , Inyecciones , Trastornos de la Visión , Ojo , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/terapiaRESUMEN
In this paper, the physicochemical properties, surface charge, and crystal defects of MIL-88A (Al) were controlled by adjusting the ratio of metal ligands and temperature in the synthetic system without the addition of surfactants. The adsorption properties of different crystals for Congo red (CR) were studied. Among them, MIL-88A (Al)-130 and MIL-88A (Al)-d have the best adsorption properties. The maximum adsorption capacities are 600.8 and 1167 mg · g-1, respectively. Compared with MIL-88A (Al)-130, the adsorption performance of MIL-88A (Al)-d was increased by 94.2%, and the adsorption rate was increased by about 4 times. It can be seen that increasing the proportion of metal ligands within a certain range will improve the adsorption capacity. The structure and morphology of the adsorbent were characterized by XRD, FTIR, SEM, EDS, TGA, BET, and zeta potential. The effects of time, temperature, pH, initial solution concentration, and dosage on CR adsorption properties were systematically discussed. The pseudo-second-order kinetic model and Langmuir isothermal model can well describe the adsorption process, which indicates that the adsorption process is a single-layer chemisorption occurring on a uniform surface. According to thermodynamics, this adsorption is an endothermic process. The mechanism of CR removal is proposed as the electrostatic attraction, hydrogen bond, metal coordination effect, π-π conjugation, crystal defect, and pore-filling effect. In addition, MIL-88A (Al)-d has good repeatability, indicating that it is a good material for treating anionic dye wastewater.
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There is an urgent demand for developing highly efficient bifunctional electrocatalysts with excellent stability toward the oxygen evolution and reduction reactions (OER and ORR, respectively) for rechargeable Zn-air batteries (ZABs). In this work, NiFe nanoparticles encapsulated within ultrahigh-oxygen-doped carbon quantum dots (C-NiFe) as bifunctional electrocatalysts are successfully obtained. The accumulation of carbon layers formed by carbon quantum dots results in abundant pore structures and a large specific surface area, which is favorable for improving catalytic active site exposure, ensuring high electronic conductivity and stability simultaneously. The synergistic effect of NiFe nanoparticles enriched the number of active centers and naturally increased the inherent electrocatalytic performance. Benefiting from the above optimization, C-NiFe shows excellent electrochemical activity for both OER and ORR processes (the OER overpotential is only 291 mV to achieve 10 mA cm-2). Furthermore, the C-FeNi catalyst as an air cathode displays an impressive peak power density of 110 mW cm-2, an open-circuit voltage of 1.47 V, and long-term durability over 58 h. The preparation of this bifunctional electrocatalyst provides a design idea for the construction of bimetallic NiFe composites for high-performance Zn-air batteries.
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Since hole trapping agents do not persist in the marine environment, it is more practical to test metal protection in 3.5 wt% NaCl solution so that the photocathodic protection (PCP) technique can be effectively applied in an actual marine environment. In this paper, Bi quantum dots (QDs) and ZIF-8 nanoparticles (NPs) were successfully deposited on TiO2by hydrothermal and impregnation methods. The PCP performances of ZIF-8/Bi/TiO2composites in the marine environment without hole trapping agents were evaluated, and compared with the performances of pure TiO2, Bi/TiO2and ZIF-8/TiO2. The electrochemical impedance spectrum (EIS) fitting results demonstrate that theRctvalue of the ZIF-8/Bi/TiO2composite coupled with 316 stainless steel (SS) decreased from 7678 Ω cm2to 519.3 Ω cm2in 3.5 wt% NaCl solution, which is a decrease of about 14.8-fold compared with TiO2under the same conditions. This indicates that the deposition of Bi QDs and ZIF-8 NPs on TiO2nanotubes can improve the electron transport efficiency, which in turn slows down the rate of corrosion of 316 SS and significantly improves the PCP performance. This is not only attributable to the Schottky junction and heterojunction structures formed by Bi QDs and ZIF-8 NPs with TiO2, but also to the surface plasmon resonance effect of Bi QDs and the N-Ti-O bond structure formed between ZIF-8 and TiO2, leading to a lower electron-hole recombination efficiency and a higher electron transfer efficiency.
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BACKGROUND AND OBJECTIVE: Protease-activated receptor 1 (PAR1) is crucial in individuals with acute myocardial infarction (AMI). The continuous and prompt PAR1 activation mainly dependent on PAR1 trafficking is essential for the role of PAR1 during AMI in which cardiomyocytes are in hypoxia. However, the PAR1 trafficking in cardiomyocytes specially during the hypoxia is still unclear. METHODS AND RESULT: A rat AMI model was created. PAR1 activation with thrombin-receptor activated peptide (TRAP) had a transient effect on cardiac function in normal rats but persistent improvement in rats with AMI. Cardiomyocytes from neonatal rats were cultured in a normal CO2 incubator and a hypoxic modular incubator chamber. The cells were then subjected to western blot for the total protein expression and staining with fluorescent reagent and antibody for PAR1 localization. No change in total PAR1 expression following TRAP stimulation was observed; however, it led to increased PAR1 expression in the early endosomes in normoxic cells and decreased expression in the early endosomes in hypoxic cells. Under hypoxic conditions, TRAP restored the PAR1 expression on both cell and endosomal surfaces within an hour by decreasing Rab11A (8.5-fold; 179.93 ± 9.82% of the normoxic control group, n = 5) and increasing Rab11B (15.5-fold) expression after 4 h of hypoxia. Similarly, Rab11A knockdown upregulated PAR1 expression under normoxia, and Rab11B knockdown downregulated PAR1 expression under both normoxic and hypoxic conditions. Cardiomyocytes knocked out of both Rab11A, and Rad11B lost the TRAP-induced PAR1 expression but still exhibited the early endosomal TRAP-induced PAR1 expression under hypoxia. CONCLUSIONS: TRAP-mediated activation of PAR1 in cardiomyocytes did not alter the total PAR1 expression under normoxic conditions. Instead, it triggers a redistribution of PAR1 levels under normoxic and hypoxic conditions. TRAP reverses the hypoxia-inhibited PAR1 expression in cardiomyocytes by downregulating Rab11A expression and upregulating Rab11B expression.
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Infarto del Miocardio , Receptor PAR-1 , Animales , Ratas , Hipoxia/metabolismo , Infarto del Miocardio/metabolismo , Miocitos Cardíacos/metabolismo , Péptidos/metabolismo , Péptidos/farmacología , Receptor PAR-1/metabolismo , Receptores de Trombina/metabolismo , Trombina/metabolismo , Trombina/farmacologíaRESUMEN
Hepatic ischemia/reperfusion injury is a major cause of hypohepatia after surgical procedures such as hypovolemic shock, transplantation, and so on. In our continuous study of bioactive natural products from fungus, eight ergosterol-type sterides (1-8), including two undescribed compounds, sterolaspers A (1) and B (2), were isolated from Aspergillus sp. TJ507. Structure elucidation was accomplished by extensive spectroscopic analysis and comparison with the reported NMR data as well as X-Ray single crystal diffraction tests. Activity screen of these isolates showed 5α-stigmast-3,6-dione (3) possessing anti-hypoxia injury effects against CoCl2-induced hypoxia damage in hepatocytes. More importantly, compound 3 could improve liver function, alleviate liver damage, and restrain the hepatocellular apoptosis in hepatic ischemia/reperfusion injury murine model. As such, this ergosterol-type steride, 5α-stigmast-3,6-dione (3), might serve as lead structure for the development of novel hepatoprotective agents in the clinical treatment of hepatic ischemia/reperfusion injury.
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Hígado , Daño por Reperfusión , Ratones , Animales , Hepatocitos , Daño por Reperfusión/tratamiento farmacológico , Apoptosis , Isquemia/complicaciones , AspergillusRESUMEN
BACKGROUND: Phthalate esters (PAEs) are known to have hormone-like properties, and there is a growing trend of children expressing a gender identity different from assigned sex. However, there has been limited research in the potential links between PAEs exposure and gender identity. METHODS: A total of 571 children (278 boys) completed the follow-up from Oct 2017 to Oct 2020 in Childhood Blood Pressure and Environmental Factors (CBPEF) cohort in Xiamen, China. Urinary PAE metabolites were measured at three time of visits using ultraperformance liquid chromatography-tandem mass spectrometry. The Children's Sex Role Inventory scale was used to assess gender identity (masculinity, femininity, androgyny and undifferentiated), and Tanner definition was used to define puberty timing. Generalized linear models and log-binomial regression were used to assess the relationships between PAEs exposure, gender trait scores and gender identity. RESULTS: Overall, the concentration of most PAEs in more than 90% of participants was above the limit of detection values. In visit 1, there were 10.1% boys with femininity and 11.3% girls with masculinity; while these figures increased to 10.8% and 12.3% during follow-up, respectively. Early puberty onset accounted for 24.8% and 25.6% among boys and girls. Long-term exposure to mono-2-ethylhexyl phthalate (MEHP) (ß = 1.20, 95%CI = 0.13, 2.28), mono-2-ethyl-5-hydroxyhexyl phthalate (MEHHP) (ß = 1.25, 95%CI = 0.22, 2.28) and mono-2-ethyl-5-oxohexyl phthalate (MEOHP) (ß = 1.40, 95%CI = 0.24, 2.56) was associated with the increased differences of femininity trait scores in boys who enter puberty earlier, prolonged exposure to di(2-ethylhexyl) phthalate (DEHP) might also have such a positive impact (ß = 1.38, 95%CI = 0.36, 2.41). For gender identity, persistent exposure to low molecular weight phthalates (LMWP) was negatively associated with undifferentiated type among boys entering puberty earlier (RR = 0.18, 95%CI = 0.05, 0.75, P < 0.05), and most of the PAE metabolites exposures showed risk ratios > 1 for their femininity. CONCLUSION: Long-term exposure to PAEs increase the femininity trait scores in boys with early onset of puberty. Although the mechanisms remain to be determined, environmental pollution might have subtle, yet measurable effects on childhood gender identity. Reducing these chemicals exposure has important public implications on gender development.
Asunto(s)
Exposición a Riesgos Ambientales , Contaminantes Ambientales , Identidad de Género , Ácidos Ftálicos , Niño , Femenino , Humanos , Masculino , Estudios de Cohortes , Pueblos del Este de Asia , Exposición a Riesgos Ambientales/análisis , Contaminantes Ambientales/orina , Feminidad , Estudios Longitudinales , Masculinidad , Ácidos Ftálicos/orina , ChinaRESUMEN
OBJECTIVE: The relationships between childhood weight self-misperception and obesity-related factors particularly health markers have not been extensively discussed. This study aims to examine the associations between weight self-misperception and obesity-related knowledge, attitudes, lifestyles and cardio-metabolic markers among Chinese paediatric population. DESIGN: Cross-sectional study. SETTING: Data sourced from a national survey in Chinese seven provinces in 2013. PARTICIPANTS: Children and adolescents aged 5-19 years. RESULTS: Of the total 14 079 participants, there were 14·5 % and 2·2 % participants over-estimated and under-perceived their weight, respectively. Multi-variable logistic regression was applied to calculate OR and 95 % CI (95 % Cl) of obesity-related behaviours and cardio-metabolic markers by actual and perceived weight status. Individuals who perceived themselves as overweight/obese were more likely to have prolonged screen time, insufficient dairy intake and over sugar-sweetened beverages consumption (all P < 0·05), regardless of their weight. Furthermore, actual overweight/obese individuals had higher odds of abnormal cardio-metabolic markers, but a smaller magnitude of association was found among weight under-estimators. Among non-overweight/obese individuals, weight over-estimation was positively associated with abdominal obesity (OR: 10·49, 95 % CI: 7·45, 14·76), elevated blood pressure (OR: 1·30, 95 % CI: 1·12, 1·51) and dyslipidemia (OR: 1·43, 95 % CI: 1·29, 1·58). CONCLUSIONS: Weight over-perception was more prevalent than under-estimation, particularly in girls. Weight over-estimators tended to master better knowledge but behave more unhealthily; both weight over-perception and actual overweight/obesity status were associated with poorer cardio-metabolic markers. Future obesity intervention programmes should additionally pay attention to the population with inaccurate estimation of weight who were easily overlooked.