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1.
Langmuir ; 40(24): 12778-12791, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38843811

RESUMO

In this work, cobalt-doped oxygen-vacancies-rich BiVO4 (Co/BiVO4-Vo) was successfully synthesized for the degradation of tetracycline (TC) by activated peroxymonosulfate (PMS) under visible light. The morphologies, microstructures, and optical properties of the photocatalysts were analyzed in detail. Co/BiVO4-Vo exhibited significantly enhanced degradation, removing 92.3% of TC within 10 min, which was greater than those of pure BiVO4 (62.2%) and oxygen-vacancies-rich BiVO4 (BiVO4-Vo) (72.0%), respectively. The photogenerated charge separation and transport properties were explored through surface photovoltage (SPV), photoluminescence spectrum (PL), and UV-vis diffuse reflectance spectroscopy (UV-vis DRS) measurements. Additionally, an in-depth investigation was conducted on the photocatalytically assisted advanced oxidation processes based on SO4•- (SR-AOPs) for the degradation of organic pollutants. The experimental results showed that the introduction of oxygen vacancies and Co doping achieved an effective separation of photogenerated carriers, which could accelerate the cycling between Co3+ and Co2+ and further activate PMS. The results of free radical capture experiments and electron spin resonance (ESR) experiments showed that reactive oxygen species (ROSs) such as 1O2, •O2-, and SO4•- played a dominant role in the removal of pollutants. This work provides a novel insight into the further development of efficient and rapid PMS photoactivators for environmental remediation of water bodies.

2.
Nat Sci Sleep ; 16: 359-368, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38617037

RESUMO

Background: Pediatric obstructive sleep apnea (OSA) is a multifaceted disorder marked by recurrent upper airway obstruction during sleep, often coexisting with various medical conditions. This study, aimed to comprehensively analyze the Multifaceted Landscape of Pediatric Insights into Prevalence, Severity, and Coexisting Conditions. With a sample of 1928 participants, our study sought to determine the prevalence, severity, and associations between OSA and diverse conditions. Methods: Conducted retrospectively from February 2019 to April 2023, the study included pediatric patients. Data were collected through electronic health records, involving clinical assessments, medical histories, and diagnostic tests to establish OSA and coexisting condition diagnoses. Relationships between sleep parameters, apnea types, and severity indices were evaluated. Results: High OSA prevalence was evident across age groups, with severity peaking between 3 to 12 years. Among the participants, coexisting conditions included allergic rhinitis (59.6%), tonsillar hypertrophy (49.7%), adenoid hypertrophy (28.4%), and obesity (15.3%). Analysis revealed intriguing relationships between different sleep parameters and apnea types. Notable associations were observed between Obstructive Apnea (OA) and Central Apnea (CA), and Mixed Apnea (MA) displayed associations with both OA and CA. Hypopnea correlated directly with the Apnea-Hypopnea Index (AHI), reflecting its role in OSA severity. Conclusion: This study provides a comprehensive understanding of the intricate dynamics between pediatric OSA and coexisting conditions. The prevalence of OSA and its coexistence with various conditions underscore the need for comprehensive evaluation and management strategies. By revealing associations between different sleep parameters and apnea types, the study emphasizes the complexity of OSA diagnosis and management. These findings hold the potential to enhance clinical approaches, ultimately leading to improved care and outcomes for affected children.

3.
J Transl Med ; 22(1): 310, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38532482

RESUMO

BACKGROUND: Paraquat (PQ) is a widely used and highly toxic herbicide that poses a significant risk to human health. The main consequence of PQ poisoning is pulmonary fibrosis, which can result in respiratory failure and potentially death. Our research aims to uncover a crucial mechanism in which PQ poisoning induces senescence in epithelial cells, ultimately regulating the activation of pulmonary fibroblasts through the exosomal pathway. METHODS: Cellular senescence was determined by immunohistochemistry and SA-ß-Gal staining. The expression of miRNAs was measured by qPCR. Pulmonary fibroblasts treated with specific siRNA of SIRT1 or LV-SIRT1 were used to analysis senescent exosomes-mediated fibroblasts activation. Luciferase reporter assay and western blot were performed to elucidated the underlying molecular mechanisms. The effects of miR-217-5p antagomir on pulmonary fibrosis were assessed in PQ-poisoned mice models. RESULTS: Impairing the secretion of exosomes effectively mitigates the harmful effects of senescent epithelial cells on pulmonary fibroblasts, offering protection against PQ-induced pulmonary fibrosis in mice. Additionally, we have identified a remarkable elevation of miR-217-5p expression in the exosomes of PQ-treated epithelial cells, which specifically contributes to fibroblasts activation via targeted inhibition of SIRT1, a protein involved in cellular stress response. Remarkably, suppression of miR-217-5p effectively impaired senescent epithelial cells-induced fibroblasts activation. Further investigation has revealed that miR-217-5p attenuated SIRT1 expression and subsequently resulted in enhanced acetylation of ß-catenin and Wnt signaling activation. CONCLUSION: These findings highlight a potential strategy for the treatment of pulmonary fibrosis induced by PQ poisoning. Disrupting the communication between senescent epithelial cells and pulmonary fibroblasts, particularly by targeting the miR-217-5p/SIRT1/ß-catenin axis, may be able to alleviate the effects of PQ poisoning on the lungs.


Assuntos
Exossomos , MicroRNAs , Fibrose Pulmonar , Humanos , Camundongos , Animais , Fibrose Pulmonar/genética , Paraquat/metabolismo , Paraquat/farmacologia , beta Catenina/metabolismo , Exossomos/metabolismo , Sirtuína 1/metabolismo , Pulmão/patologia , MicroRNAs/genética , Células Epiteliais/patologia , Fibroblastos/metabolismo
4.
Dalton Trans ; 53(1): 115-122, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38050724

RESUMO

The development of photoelectrochemical (PEC) water splitting is hindered by the slow kinetics of four-electron processes for the oxygen evolution reaction (OER) and severe charge recombination. Amorphous carbon was chosen as a carrier for the active sites due to its exceptional conductivity and strong loading capacity. In addition, this enhanced performance was attributed to the loading of oxides of cobalt. Here, amorphous carbon-covered cobalt oxides chosen as a co-catalyst loaded on α-Fe2O3 (noted as CoOx@C/Ti-Fe2O3) have been synthesized, and they show a high current density (2.86 mA cm-2 under 1.23 V vs. RHE), and a low onset potential (0.611 V vs. RHE). Experimental analysis demonstrates that the charge transfer and separation leading to accelerated OER dynamics and improved PEC performance are enhanced by CoOx@C effectively. This study provides new ideas for designing high-performance photoelectrochemical electrodes based on amorphous carbon co-catalysts.

5.
J Colloid Interface Sci ; 650(Pt B): 1022-1031, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37459726

RESUMO

The kinetic competition between water oxidation/electron extraction processes and recombination behaviors is a key consideration in the development of efficient photoanodes for solar-driven water splitting. Investigating the photogenerated charge behaviors could guide the construction of high-efficiency photoanodes. In this study, the charge carrier kinetics involved in photoelectrochemical water oxidation of PDS/Ti-Fe2O3 were analyzed using surface photovoltage (SPV), transient photovoltage (TPV), short-pulse transient photocurrent (TPC) and photoelectrochemical impedance spectra (PEIS). The TPC results indicate the interfacial electric field introduced by the PDS loading increases the electron extraction and suppresses the bulk recombination, enhancing the spatial separation of photogenerated charges, which is consistent with the SPV and TPV results. Besides, the surface recombination of the back electron (BER) is also attenuated, which enhances the long-lived holes at the surface of PDS/Ti-Fe2O3 photoanode. Similarly, as obtained by PEIS fitting, the loading of PDS accelerates holes transfer at the photoanode/electrolyte interface, and increases the utilization of long-lived holes. In other word, the recombination behaviors of photogenerated charges are restrained both in the bulk and surface of the photoanode after the deposition of PDS, leading to enhanced PEC performance. These findings highlight the importance of understanding charge carrier dynamics in the design of high-efficient photoanodes.

6.
J Colloid Interface Sci ; 649: 492-500, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37356150

RESUMO

Ti-ZnFe2O4 photoanode has attracted extensive attention in photoelectrochemical (PEC) water oxidation due to its narrow band gap and good photostability. However, its low efficiency limits its development. Herein, we designed and constructed direct Z-scheme Ti-ZnFe2O4/In2O3 (Ti-ZFO/In2O3) photoanode. Under the interface electric field, photogenerated holes with stronger oxidation capacity on In2O3 are retained to participate in the water oxidation reaction, and the photocurrent density of Ti-ZFO/In2O3 is much higher than that of pure Ti-ZFO, reaching 2.2 mA/cm2 at 1.23 V vs. RHE. Kelvin Probe, steady-state photovoltage spectroscopy (SPV), transient photovoltage spectroscopy (TPV) and in-situ double beam strategy were used to demonstrate the Z-scheme charge transfer mechanism of Ti-ZFO/In2O3 photoanode. Our work provides an effective scheme and technical means for further understanding the mechanism of interfacial charge transfer.

7.
Mediators Inflamm ; 2023: 5380764, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37181812

RESUMO

Background: Matrix metalloproteinase-7 (MMP7) is markedly expressed in patients with chronic kidney disease; its expression in dialysate and role in patients undergoing peritoneal dialysis (PD) have not been well established. Methods: Participants undergoing PD from June 1st, 2015, to June 30th, 2020, were involved and were followed up every 3 months for the first year and every 6 months thereafter until death, PD withdrawal, or the end of the study. Data at each follow-up point were collected and analyzed for the association with congestive heart failure (CHF), PD withdrawal, and combined endpoint. Results: A total of 283 participants were included in this study. During a median follow-up of 21 months, 20 (7%) participants died, 93 (33%) withdrew from PD, and 105 (37%) developed CHF. A significantly increased level of serum and dialysate MMP7 was observed at baseline. Dialysate MMP7 presented a good linearity with serum MMP7. Baseline serum and dialysate MMP7 levels were associated with CHF in multivariable Cox proportional hazards regression models. After categorization, participants with high baseline MMP7 levels had a higher incidence of CHF (42%), and the hazard ratios (95% confidence intervals) were 1.595 (1.023-2.488). Interestingly, participants with higher serum MMP7 levels were trended to use dialysate with higher glucose concentration. However, the ultrafiltration volumes were not significantly increased. Higher MMP7 levels were also positively associated with PD withdrawal and combined endpoint. Conclusions: The expression of MMP7 in serum and dialysate was markedly increased and was tightly associated with the risk of CHF in PD patients. This finding suggests that the measurement of MMP7 may inform strategies for managing CHF at an earlier stage.


Assuntos
Insuficiência Cardíaca , Falência Renal Crônica , Diálise Peritoneal , Humanos , Metaloproteinase 7 da Matriz , Estudos Prospectivos , Falência Renal Crônica/terapia , Falência Renal Crônica/complicações , Diálise Peritoneal/efeitos adversos , Soluções para Diálise , Insuficiência Cardíaca/complicações
8.
Langmuir ; 38(50): 15817-15826, 2022 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-36490371

RESUMO

The effectiveness of photocatalytic and Fenton reactions in the synergistic treatment of water pollution problems has become indisputable. In this paper, nitrogen-doped TiO2 was selected as the catalyst for the photocatalytic reaction and manganese-substituted phosphomolybdic acid was used as the Fenton reagent, the two of which were combined together by acid impregnation to construct a binary photocatalysis-Fenton composite catalyst. The degradation experiments of the composite catalyst on RhB indicated that under UV-vis irradiation, the composite catalyst could degrade RhB almost completely within 8 min, and the degradation rate was 19.7 times higher than that of N-TiO2, exhibiting a superior degradation ability. Simultaneously, a series of characterization methods were employed to analyze the structure, morphology, and optical properties of the catalysts. The results demonstrated that the nitrogen doping not only expanded the photo response range of TiO2 but reduced the work function of TiO2, which facilitated the transfer of electrons to the loaded Mn-HPMo side and further promoted the electron-hole separation efficiency. In addition, the introduction of Mn-HPMo provided three pathways for the activation of hydrogen peroxide, which enhanced the degradation activity. This study provides novel insights into the construction of binary and efficient catalysts with multiple hydroxyl radical generation pathways.


Assuntos
Manganês , Nitrogênio , Nitrogênio/química , Catálise
9.
Dalton Trans ; 51(47): 17938-17941, 2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36413053

RESUMO

Photogenerated carrier behavior at a CO2/Cs2AgBiBr6 quantum dot (QD) interface is investigated. In situ photovoltage spectra reveal electron transfer from the Cs2AgBiBr6 QDs to CO2. Moreover, this carrier transfer prefers Bi3+ sites (over Ca+ and Ag+ sites) due to them exhibiting the lowest adsorption energy (Eads = -0.125 eV) and CO2-Bi3+ interactions being more stable.

10.
Plant Dis ; 2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36383990

RESUMO

Blueberry has high nutritional value and is one of the five healthy fruits. In 2018, leaf spots and stem blights were observed on Vaccinium corymbosum cv. Bluerain in Guangzhou, Guangdong Province, China. Up to 80% of the plants were affected. Initial symptoms of affected leaves were red-brown, irregular, small spots, which gradually coalesced and formed larger irregular necrotic patches. The affected stems showed red-brown and irregular large lesions. Diseased tissues were surface sterilized with 75% alcohol for 15 s, followed by 2.5% NaClO for 30 s, and rinsing three times in sterile distilled water, placed on potato dextrose agar (PDA) and incubated at 25 C. Representative strains, ZHKUCC 21-0021 from diseased leaves and ZHKUCC 21-0073 from diseased stems, were selected for further studies. Colonies grew slowly at 25 C on malt extract agar (MEA) (average 5.68 mm/d), producing white aerial mycelium and red-brown color on the underside after 7 days. Macroconidiophores were hyaline, smooth, consisting of a stipe bearing fertile branches, and a stipe extension terminating in a vesicle. Each terminal branch produced 2-4 phialides, 8-13 × 3-6 µm, reniform or doliiform; Stipe extensions were septate, terminating in a narrowly clavate vesicle, 2-6 µm. Macroconidia were hyaline, straight cylindrical, round at both ends, 83-100 × 7-11 µm (average = 94 × 8 µm; n = 50), with 5 septa. These morphological characteristics were similar to the description of Calonectria pseudoreteaudii (Lombard et al., 2010). The partial calmodulin (cmdA), beta-tubulin (ß-tubulin), and translation elongation factor 1-alpha (tef1-α) genes of the two isolates were respectively amplified using primers CAL-228F/CAL-737R (Carbone et al., 1999), EF1-728F/EF2 and T1/CYLTUB1R (Lombard et al., 2015), and sequences were deposited in GenBank (cmdA: MZ516854 and MZ516855; ß-tubulin: MZ516858 and MZ516859; tef1-α: MZ516856 and MZ516857). BLAST analysis of three gene sequences showed 100% similarity to those of C. pseudoreteaudii. In the maximum likelihood (ML) tree of the concatenated sequences of the three genes, the two isolates from this study were clustered with C. pseudoreteaudii with 100% bootstrap support. Five-mm-diameter hyphal plugs of two representative isolates grown on PDA for five days were used in the pathogenicity test. Leaves were inoculated with ZHKUCC 21-0021, and stems were inoculated with ZHKUCC 21-0073 with five replicates. As controls, sterile PDA plugs were used. All inoculated plants were maintained at 25 C . After 7 days, inoculated leaves and stems developed symptoms similar to field samples, whereas the control plants remained asymptomatic. The pathogen was reisolated from inoculated plants and confirmed to be C. pseudoreteaudii by morphological characteristics. Five Calonectria species (C. canadensis, C. colhounii, C. ilicicola, C. kyotensis and C. pyrochroa), have been reported associated with blueberry (Farr and Rossman, 2022; Fei et al, 2017). Calonectria canadensis and C. ilicicola have been reported to cause stem blight and stem rot in Vaccinium spp. in China (Fei et al, 2017 and 2018). Calonectria colhounii has been reported to cause stem blight in V. angustifolium and V. corymbosum in the United States (Sadowsky et al, 2011). However, this is the first report of C. pseudoreteaudii causing leaf spot and stem blight on Vaccinium spp. worldwide. These results will provide a foundation for future research on prevention and control of this disease.

11.
Dalton Trans ; 51(45): 17292-17300, 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36317601

RESUMO

Interface modification is an important means to enhance the photovoltaic performance of quantum dot sensitized solar cells (QDSCs). The TiO2/CdS/CdSe solar cells are sensitized with CdS QDs and CdSe QDs, which inevitably introduces a new interface to form a recombination center. Therefore, it is necessary to coat a passivation layer in order to effectively inhibit charge recombination at the CdS/CdSe interface. In this work, CuInS2 (CIS) has been introduced into the CdS/CdSe QD system as an inner passivation layer and the CdS/CIS/CdSe photoanode structure has been fabricated in an environmentally friendly manner. The extracted charge amount (Q) is used to express the charge separation efficiency, indicating that we have obtained outstanding charge extraction efficiency in CIS based CdS/CdSe QDSCs. As a result, the photocurrent density of the TiO2/CdS/CIS/CdSe photoanode significantly has increased from 19.01 mA cm-2 to 22.74 mA cm-2 (TiO2/CdS/CdSe photoanode), which demonstrates a higher photoconversion efficiency of 4.52% in comparison with that of TiO2/CdS/CdSe photoanode.

12.
Angew Chem Int Ed Engl ; 61(40): e202208174, 2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-35960211

RESUMO

Here we report a new type of chiral all-carbon tetrasubstituted VQMs generated via chiral phosphoric acids catalyzed nucleophilic addition of 2-alkynylnaphthols to o-quinone methides or imines, which can be captured intramolecularly as a result of cycloaddition reaction. A new class of naphthyl-2H-chromenes bearing axially and centrally chiral elements and axially chiral quinone-naphthols were prepared efficiently with good to excellent yields, diastereoselectivities and enantioselectivities. Noteworthy, the enantioselective cycloaddition of alkynylnaphthols with o-quinone methides proceeded via a [2+2] cycloaddition, followed by a retro-4π-electrocyclization and a 6π re-cyclization. While the cycloaddition of alkynylnaphthols with imines proceeded via a sequential [2+4] cycloaddition and an auto oxidation reaction. Moreover, the obtained axially chiral naphthols can be converted into valuable phosphine ligands and other functional molecules.

13.
IEEE Trans Med Imaging ; 41(11): 3167-3181, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35657830

RESUMO

Use of synthetic data has provided a potential solution for addressing unavailable or insufficient training samples in deep learning-based magnetic resonance imaging (MRI). However, the challenge brought by domain gap between synthetic and real data is usually encountered, especially under complex experimental conditions. In this study, by combining Bloch simulation and general MRI models, we propose a framework for addressing the lack of training data in supervised learning scenarios, termed MOST-DL. A challenging application is demonstrated to verify the proposed framework and achieve motion-robust [Formula: see text] mapping using single-shot overlapping-echo acquisition. We decompose the process into two main steps: (1) calibrationless parallel reconstruction for ultra-fast pulse sequence and (2) intra-shot motion correction for [Formula: see text] mapping. To bridge the domain gap, realistic textures from a public database and various imperfection simulations were explored. The neural network was first trained with pure synthetic data and then evaluated with in vivo human brain. Both simulation and in vivo experiments show that the MOST-DL method significantly reduces ghosting and motion artifacts in [Formula: see text] maps in the presence of unpredictable subject movement and has the potential to be applied to motion-prone patients in the clinic. Our code is available at https://github.com/qinqinyang/MOST-DL.


Assuntos
Algoritmos , Artefatos , Humanos , Movimento (Física) , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos
14.
Clin Chim Acta ; 530: 45-49, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35248528

RESUMO

BACKGROUND AND AIMS: Spinal muscular atrophy (SMA) is an autosomal recessive neurodegenerative disorder caused by SMN1 gene mutations. About 40% of SMN1 subtle mutations produced premature termination codons (PTC). This study aims to determine the capacity of these PTCs to trigger nonsense-mediated mRNA decay (NMD) pathway. METHODS: Three nonsense mutations in SMN1, including c.43C > T, c.683T > A and c.844C > T, were investigated by using a minigene system and in vivo splicing assays. Two strategies were supplied: administration of cycloheximide (NMD inhibitor) and knockdown of UPF1 (a key NMD factor) in the cells carrying different minigenes. RESULTS: The wild-type minigene exclusively produced correctly spliced transcripts (FL-SMN1). Both the 683T > A and 844C > T expressed remarkably lower FL-SMN1 than the wild-type cells. After cycloheximide treatment, the FL-SMN1 levels in both the 683T > A and 844C > T were increased significantly compared with that of untreated cells. UPF1 knockdown in both the mutant 683T > A and 844C > T caused a dramatically augmentation of FL-SMN1 as compared to that in the cells treated with non-specific control siRNAs. CONCLUSION: Our data provide evidence that c.683T > A and c.844C > T, but not c.43C > T, in SMN1 leading to SMA trigger NMD using a minigene system. Therefore, NMD should be taken into consideration when exploring the pathogenetic mechanisms for these mutations.


Assuntos
Códon sem Sentido , Atrofia Muscular Espinal , Códon sem Sentido/genética , Cicloeximida/farmacologia , Humanos , Atrofia Muscular Espinal/genética , Degradação do RNAm Mediada por Códon sem Sentido , RNA Helicases/genética , RNA Helicases/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteína 1 de Sobrevivência do Neurônio Motor/genética , Proteína 1 de Sobrevivência do Neurônio Motor/metabolismo , Transativadores/genética , Transativadores/metabolismo
15.
IEEE Trans Med Imaging ; 41(7): 1791-1801, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35130151

RESUMO

Detecting 3D landmarks on cone-beam computed tomography (CBCT) is crucial to assessing and quantifying the anatomical abnormalities in 3D cephalometric analysis. However, the current methods are time-consuming and suffer from large biases in landmark localization, leading to unreliable diagnosis results. In this work, we propose a novel Structure-Aware Long Short-Term Memory framework (SA-LSTM) for efficient and accurate 3D landmark detection. To reduce the computational burden, SA-LSTM is designed in two stages. It first locates the coarse landmarks via heatmap regression on a down-sampled CBCT volume and then progressively refines landmarks by attentive offset regression using multi-resolution cropped patches. To boost accuracy, SA-LSTM captures global-local dependence among the cropping patches via self-attention. Specifically, a novel graph attention module implicitly encodes the landmark's global structure to rationalize the predicted position. Moreover, a novel attention-gated module recursively filters irrelevant local features and maintains high-confident local predictions for aggregating the final result. Experiments conducted on an in-house dataset and a public dataset show that our method outperforms state-of-the-art methods, achieving 1.64 mm and 2.37 mm average errors, respectively. Furthermore, our method is very efficient, taking only 0.5 seconds for inferring the whole CBCT volume of resolution 768×768×576 .


Assuntos
Pontos de Referência Anatômicos , Memória de Curto Prazo , Cefalometria/métodos , Tomografia Computadorizada de Feixe Cônico/métodos , Imageamento Tridimensional/métodos , Reprodutibilidade dos Testes
16.
Fish Shellfish Immunol ; 120: 242-251, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34856372

RESUMO

Fishes can adapt to certain levels of environmental ammonia in water, but the strategies utilized to defend against ammonia toxicity are not exactly the same. The carbamyl phosphate synthase I (CPS I) plays an important role in the regulation of glutamine synthesis and urea cycle, which are the most common strategies for ammonia detoxification. In this study, CPS I was cloned from the yellow catfish. The full-length cDNAs of the CPS I was 5 034 bp, with open reading frames of 4 461 bp. Primary amino acid sequence alignment of CPS I revealed conserved similarity between the functional domains of the yellow catfish CPS I protein with CPS I proteins of other animals. The mRNA expression of CPS I was significantly up-regulated in liver and kidney tissues after acute ammonia stress. The CPS I RNA interference (RNAi) down-regulated the mRNA expressions of CPS I and ornithine transcarbamylase (OTC), but up-regulated glutamine synthetase (GS) and glutamate dehydrogenase (GDH) expressions in primary culture of liver cell after acute ammonia stress. Similarly, the activity of enzymes related to urea cycle decreased significantly, while the activity of enzymes related to glutamine synthesis increased significantly. The results of RNAi in vitro suggested that when the urea cycle is disturbed, the glutamine synthesis will be activated to cope with ammonia toxicity.


Assuntos
Amônia , Carbamoil-Fosfato Sintase (Amônia) , Peixes-Gato , Glutamina/biossíntese , Ureia , Amônia/toxicidade , Animais , Carbamoil-Fosfato Sintase (Amônia)/genética , Peixes-Gato/genética , Peixes-Gato/metabolismo , Proteínas de Peixes/genética , Fígado , RNA Mensageiro
17.
Dalton Trans ; 50(43): 15551-15557, 2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34665188

RESUMO

Decorating a high-efficiency oxygen evolution reaction (OER) electrocatalyst as a cocatalyst on an α-Fe2O3 photoanode is known to be one of the most efficient methods to improve the photoelectrochemical (PEC) water oxidation activity. In our work, different from traditional methods of transition metal sulfide cocatalyst synthesis, an NiFeSx-decorated Ti-Fe2O3 photoanode is synthesized through a simple one-step electrodeposition method, which benefits the interface between Ti-Fe2O3 and NiFeSx. With the help of this excellent OER electrocatalyst, the photocurrent density of the NiFeSx-Ti-Fe2O3 photoanode rises to 3 mA cm-2 at 1.23 V vs. RHE, which is 2.5 times greater than the photocurrent of Ti-Fe2O3. Moreover, the onset potential of NiFeSx-Ti-Fe2O3 shifts negatively by 170 mV compared with that of pure Ti-Fe2O3. Furthermore, surface photovoltage spectroscopy (SPV) and transient photovoltage (TPV) techniques and photoelectrochemical impedance spectroscopy (PEIS) were used to analyze the true effects of NiFeSx as an efficient cocatalyst for enhancing the PEC performance of the NiFeSx-Ti-Fe2O3 photoanode. This work provides a simple method for loading a low-cost and efficient cocatalyst to modify a Ti-Fe2O3 photoanode for the PEC water oxidation reaction.

18.
Front Med (Lausanne) ; 8: 728009, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34595194

RESUMO

Objective: This study aims to investigate the relationship between dietary salt intake and residual renal function in peritoneal dialysis (PD) patients. Methods: The daily salt intake of the patients was calculated based on a 3 day dietary record. Sixty-two patients were divided into three groups: 33 patients in the low salt intake group (salt intake <6.0 g/day), 17 in the medium salt intake group (salt intake 6.0 to <8.0 g/day), and 12 in the high salt intake group (salt intake ≥8.0 g/day). Regular follow-up was conducted every 3 months. Urine volume, peritoneal ultrafiltration volume, and other clinical indicators were recorded. Biochemical indexes were detected to evaluate the changes in residual renal function and peritoneal function during follow-up. Results: A positive correlation between dietary sodium intake and sodium excretion was found. During 12-month follow-up, a decrease of residual renal function showed a significant difference among the three groups (p = 0.041) (15.3 ± 27.5 vs. 12.5 ± 11.5 vs. 32.9 ± 18.4 L/W/1.73 m2 in the low-, medium-, and high salt intake groups, respectively). Consistently, a higher decline of residual renal function (adjusted ß, 20.37; 95% CI, 2.83, 37.91) was found in participants with high salt intake (salt intake ≥8 g/day) compared with those in non-high salt intake. Conclusion: Our study showed that the sodium excretion by peritoneal dialysis was positively correlated with dietary sodium intake in PD patients. The high salt intake diet (salt intake ≥8 g/day) may lead to a faster decline of residual renal function in PD patients.

19.
J Environ Sci (China) ; 106: 147-160, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34210430

RESUMO

The extensive use of tetracycline hydrochloride (TCH) poses a threat to human health and the aquatic environment. Here, magnetic p-n Bi2WO6/CuFe2O4 catalyst was fabricated to efficiently remove TCH. The obtained Bi2WO6/CuFe2O4 exhibited 92.1% TCH degradation efficiency and 50.7% and 35.1% mineralization performance for TCH and raw secondary effluent from a wastewater treatment plant in a photo-Fenton-like system, respectively. The remarkable performance was attributed to the fact that photogenerated electrons accelerated the Fe(III)/Fe(II) and Cu(II)/Cu(I) conversion for the Fenton-like reaction between Fe(II)/Cu(I) and H2O2, thereby generating abundant •OH for pollutant oxidation. Various environmental factors including H2O2 concentration, initial pH, catalyst dosage, TCH concentration and inorganic ions were explored. The reactive oxidation species (ROS) quenching results and electron spin resonance (ESR) spectra confirmed that •O2- and •OH were responsible for the dark and photo-Fenton-like systems, respectively. The degradation mechanisms and pathways of TCH were proposed, and the toxicity of products was evaluated. This work contributes a highly efficient and environmentally friendly catalyst and provides a clear mechanistic explanation for the removal of antibiotic pollutants in environmental remediation.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Purificação da Água , Humanos , Peróxido de Hidrogênio , Ferro , Oxirredução , Poluentes Químicos da Água/análise
20.
Langmuir ; 37(24): 7617-7624, 2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34115506

RESUMO

A series of Al-doped BiVO4 composites have been synthesized via the hydrothermal method for methylene blue (MB) degradation application. The reasons for the improvement of photocatalytic performance was explained from the perspective of optics. Transient photovoltage (TPV) measurements suggested that the surface states have the priority to capture photogenerated carriers, and the Al2O3 surface passivation layer can prolong the lifetime of charge carrier. The results of surface photovoltage (SPV), transient photovoltage (TPV), and surface photocurrent (SPC) measurements suggested that the coexistence of Al3+ and Al2O3 caused by the appropriate doping would improve the transfer property and prolong the lifetime of photogenerated carriers. Finally, the possible photocatalytic mechanism is expounded to illustrate the photogenerated charge behavior under visible light irradiation. This work provides a better understanding of the synergistic effect of Al-doping and Al2O3 passivation layer on enhancing the photocatalytic performance.

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