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1.
Proc Natl Acad Sci U S A ; 121(4): e2314396121, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38236736

RESUMO

In our quest to leverage the capabilities of the emerging single-atom catalysts (SACs) for wastewater purification, we confronted fundamental challenges related to electron scarcity and instability. Through meticulous theoretical calculations, we identified optimal placements for nitrogen vacancies (Nv) and iron (Fe) single-atom sites, uncovering a dual-site approach that significantly amplified visible-light absorption and charge transfer dynamics. Informed by these computational insights, we cleverly integrated Nv into the catalyst design to boost electron density around iron atoms, yielding a potent and flexible photoactivator for benign peracetic acid. This exceptional catalyst exhibited remarkable stability and effectively degraded various organic contaminants over 20 cycles with self-cleaning properties. Specifically, the Nv sites captured electrons, enabling their swift transfer to adjacent Fe sites under visible light irradiation. This mechanism accelerated the reduction of the formed "peracetic acid-catalyst" intermediate. Theoretical calculations were used to elucidate the synergistic interplay of dual mechanisms, illuminating increased adsorption and activation of reactive molecules. Furthermore, electron reduction pathways on the conduction band were elaborately explored, unveiling the production of reactive species that enhanced photocatalytic processes. A six-flux model and associated parameters were also applied to precisely optimize the photocatalytic process, providing invaluable insights for future photocatalyst design. Overall, this study offers a molecule-level insight into the rational design of robust SACs in a photo-Fenton-like system, with promising implications for wastewater treatment and other high-value applications.

2.
Environ Sci Technol ; 58(27): 12155-12166, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38934735

RESUMO

The rising in situ chemical oxidation (ISCO) technologies based on polymerization reactions have advanced the removal of emerging contaminants in the aquatic environment. However, despite their promise, uncertainties persist regarding their effectiveness in eliminating structurally complex contaminants, such as sulfonamide antibiotics (SAs). This study elucidated that oligomerization, rather than mineralization, predominantly governs the removal of SAs in the carbon materials/periodate system. The amine groups in SAs played a crucial role in forming organic radicals and subsequent coupling reactions due to their high f- index and low bond orders. Moreover, the study highlighted the robust adhesion of oligomers to the catalyst surface, facilitated by enhanced van der Waals forces and hydrophobic interactions. Importantly, plant and animal toxicity assessments confirmed the nontoxic nature of oligomers deposited on the carbon material surface, affirming the efficacy of carbon material-based ISCO in treating contaminated surface water and groundwater. Additionally, a novel classification approach, Δlog k, was proposed to differentiate SAs based on their kinetic control steps, providing deeper insights into the quantitative structure-activity relationship (QSAR) and facilitating the selection of optimal descriptors during the oligomerization processes. Overall, these insights significantly enhance our understanding of SAs removal via oligomerization and demonstrate the superiority of C-ISCO based on polymerization in water decontamination.


Assuntos
Antibacterianos , Carbono , Sulfonamidas , Antibacterianos/química , Carbono/química , Sulfonamidas/química , Poluentes Químicos da Água/química , Purificação da Água
3.
Support Care Cancer ; 31(7): 444, 2023 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-37410217

RESUMO

OBJECTIVE: To investigate their compliance with postoperative oral nutritional supplementation and nutritional outcomes. METHODS: A total of 84 patients with colorectal cancer surgery with NRS-2002 risk score ≥ 3 who were treated with oral nutritional supplementation were selected and divided into control and observation groups according to the random number table method, with 42 cases in each group. The control group received conventional oral nutritional supplementation and dietary nutrition education; the observation group established a nutrition intervention group based on the Goal Attainment Theory and carried out individualized nutrition education based on the Goal Attainment Theory. The nutritional indicators at 1 day postoperative, 7 days postoperative, oral nutritional supplementation adherence scores at 7 and 14 days postoperative, and the attainment rate of trans-oral nutritional intake at 21 days postoperative were compared between the 2 groups of patients. RESULTS: There was no statistically significant difference between the nutritional status indexes of the 2 groups of patients before the intervention, p > 0.05; when comparing the prealbumin of the 2 groups of patients at 7 days postoperatively, the prealbumin level of the patients in the observation group at 7 days postoperatively (200.25 ± 53.25) was better than that of the control group (165.73 ± 43.00), with a p value of 0.002, and the difference was statistically significant (p < 0.05). Comparison of oral nutritional supplementation adherence scores at 7 and 14 days postoperatively showed that ONS treatment adherence scores were better than those of the control group, with statistically significant differences (p < 0.05). When comparing the attainment rate of oral nutritional intake at 21 days after surgery, the difference was statistically significant (p < 0.05). CONCLUSION: Nutritional education based on the Goal Attainment Theory can effectively improve the adherence to oral nutritional supplementation therapy and protein intake attainment rate of colorectal cancer patients after surgery and effectively improve the nutritional status of patients.


Assuntos
Neoplasias Colorretais , Terapia Nutricional , Humanos , Pré-Albumina , Objetivos , Estado Nutricional , Suplementos Nutricionais , Neoplasias Colorretais/cirurgia
4.
BMC Endocr Disord ; 22(1): 174, 2022 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-35804355

RESUMO

BACKGROUND: Tumor-related osteomalacia (TIO) is a rare paraneoplastic syndrome characterized by severe hypophosphatemia and osteomalacia. The diagnosis of TIO can be very difficult because of its nonspecific nature of clinical manifestations. Here we reported a case of young TIO patient with "painful knee joint with difficulty in moving" to improve the clinical diagnosis and treatment levels. CASE PRESENTATION: The patient's clinical features were consistent with TIO. A tumor was successfully located in left tibial by 68Ga-DOTATATE PET/CT, and then was surgically resected. Upon pathologic assessment, the tumor was diagnosed as phosphaturia stromal tumor (PMT) with positive Vim staining. After the surgery, serum phosphate level rapidly recovered and symptoms significantly improved. CONCLUSION: TIO should be considered in patients with chronically hypophosphorus osteomalacia in the setting of no family history. Early removal of the responsible tumors is clinically essential for the treatment, and imaging examination is of great significance for tumor localization.


Assuntos
Osteomalacia , Síndromes Paraneoplásicas , Humanos , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/patologia , Articulação do Joelho/cirurgia , Osteomalacia/etiologia , Osteomalacia/cirurgia , Síndromes Paraneoplásicas/etiologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Tomografia por Emissão de Pósitrons , Cintilografia
5.
Nat Commun ; 15(1): 7783, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39237589

RESUMO

The artificial photocatalytic synthesis based on graphitic carbon nitride (g-C3N4) for H2O2 production is evolving rapidly. However, the simultaneous production of high-value products at electron and hole sites remains a great challenge. Here, we use transformable potassium iodide to obtain semi-crystalline g-C3N4 integrated with the I-/I3- redox shuttle mediators for efficient generation of H2O2 and benzaldehyde. The system demonstrates a prominent catalytic efficiency, with a benzaldehyde yield of 0.78 mol g-1 h-1 and an H2O2 yield of 62.52 mmol g-1 h-1. Such a constructed system can achieve an impressive 96.25% catalytic selectivity for 2e- oxygen reduction, surpassing previously reported systems. The mechanism study reveals that the strong crystal electric field from iodized salt enhances photo-generated charge carrier separation. The I-/I3- redox mediators significantly boost charge migration and continuous electron and proton supply for dual-channel catalytic synthesis. This groundbreaking work in photocatalytic co-production opens neoteric avenues for high-value synthesis.

6.
Water Res ; 260: 121907, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38878318

RESUMO

The combination of ozone (O3) and ferrate (Fe(VI)) oxidation technology demonstrates substantial potential for practical applications, though it has been underreported, resulting in gaps in comprehensive activity assessments and thorough exploration of its mechanisms. This study reveals that the previous use of a borate buffer solution obscured certain synergistic reactions between O3 and Fe(VI), causing a reduction of activity by ∼40 % when oxidizing the electron-deficient pollutant atrazine. Consequently, we reassessed the activity and mechanisms using a buffer-salt-free O3/Fe(VI) system. Our findings showed that the hydroxyl radical (·OH) served as the predominant active species, responsible for an impressive 95.9 % of the oxidation activity against electron-deficient pollutants. Additional experiments demonstrated that the rapid production of neglected and really important superoxide radicals (·O2-) could facilitate the decomposition of O3 to generate ·OH and accelerate the reduction of Fe(VI) to Fe(V), reactivating O3 to produce ·OH anew. Intriguingly, as the reaction progressed, the initially depleted Fe(VI) was partially regenerated, stabilizing at over 50 %, highlighting the significant potential of this combined system. Moreover, this combined system could achieve a high mineralization efficiency of 80.4 % in treating actual coking wastewater, complemented by extensive toxicity assessments using Escherichia coli, wheat seeds, and zebrafish embryos, showcasing its robust application potential. This study revisits and amends previous research on the O3/Fe(VI) system, providing new insights into its activity and synergistic mechanisms. Such a combined technology has potential for the treatment of difficult-to-degrade industrial wastewater.


Assuntos
Ferro , Oxirredução , Ozônio , Poluentes Químicos da Água , Ozônio/química , Ferro/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/toxicidade , Animais , Radical Hidroxila/química , Atrazina/química , Atrazina/toxicidade , Elétrons , Peixe-Zebra
7.
Ultrasonics ; 134: 107079, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37348361

RESUMO

Using the stress wave generated by radial excitation, an ultrasonic transducer with pure torsional output based on a radial chute is developed. Based on the reflection principle of the stress wave from the radial chute, the mechanical model of the radial wave entering the chute disc then synthesizing the circumferential wave is established, and the stress state of the stress wave after the radial wave acts on the chute is deduced. On this basis, the influence of the chute angle on the circumferential wave is obtained. Theoretical analysis shows that there is an optimal chute angle for the synthesis of the circumferential wave. Then, the optimal inclined chute disc and ultrasonic transducer are selected for modal analysis. In the simulation, the radial wave generated by the excitation is evenly distributed at the disc and effectively converted into a circumferential wave. The converted circumferential wave is transmitted to the output end through the amplitude transformer of pure torsional mode, and the ultrasonic transducer realizes pure in-plane torsional output. When measured, the circumferential amplitude of the output rod is 5.22 times of the radial amplitude of the chute disc.

8.
J Med Biochem ; 42(1): 86-93, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36819136

RESUMO

Background: This paper explores the assessment value of pathological condition of serum adiponectin (APN) and amylin in primary osteoporosis (POP) and their correlation with bone metabolism indexes. Methods: From January 2019 to June 2021, 79 cases of POP patients were selected as the research objects. A test of the patients' bone density was conducted, and clinical grading of POP was via T value (normal, mild, moderate, severe). The analysis of the assessment value of pathological condition of serum APN and amylin for POP and their association with bone metabolism indexes in patients was performed. Results: APN and amylin in patients were declined with POP's aggravation. APN of 5.15 µg/mL or less and amylin of 15.38 pmol/L or less were risk factors influencing the aggravation of pathological condition of POP (P< 0 .0 5). The area under the curve (AUC) of combined detection of APN and amylin to assess the severity of POP was elevated vs. alone test of amylin (P< 0.05). 25-hydroxyvitamin D (25-(OH) D) and total type 1 procollagen amino-terminal propeptide (t-PINP) in patients were descended with the aggravation of pathological condition of osteoporosis (P < 0.05). At the same time, no distinct differences were presented in the three groups of type I collagen hydroxyl terminal peptide b degradation product (ß-CTX) and N-terminal osteocalcin (N-MID) (P> 0.05). APN, amylin, 25-(OH)D, ß-CTX, and t-PINP were negatively linked with POP clinical grade (P< 0.05). APN and amylin were associated with 25-(OH) D, ß-CTX, t-PINP (P< 0.05), and APN and amylin were not linked with N-MID (P> 0.05). Conclusions: Serum APN and amylin are provided with evaluation values for the severity of POP and are associated with bone metabolism in patients.

9.
Biomed Res Int ; 2022: 1034316, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35813225

RESUMO

Human adipose-derived stem cells (ADSCs) have become a promising therapeutic approach against skin aging. Recent studies confirm that exosomes partially mediate the therapeutic effect of stem cells. This study successfully isolated exosomes from the ADSC culture medium and discovered that ADSC-derived exosomes (ADSC-Exos) could alleviate human dermal fibroblast (HDF) senescence and stimulate HDF migration. Moreover, ADSC-Exos increased the type I collagen expression level and reduced the reactive oxygen species (ROS) and senescence-associated ß-galactosidase (SA-ß-Gal) activity in HDFs. In addition, we demonstrated that ADSC-Exos significantly inhibited senescence-related protein expression levels of p53, p21, and p16. In conclusion, our results have revealed the antisenescence effects of ADSC-Exos on HDFs and ADSC-Exos may be a novel cell-free therapeutic tool for antiaging.


Assuntos
Exossomos , Adipócitos , Tecido Adiposo/metabolismo , Proliferação de Células , Exossomos/metabolismo , Fibroblastos/metabolismo , Humanos , Células-Tronco/metabolismo
10.
Micromachines (Basel) ; 11(3)2020 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-32120858

RESUMO

Based on an analysis of the precision and preparation technology of an optical texture film with a triangular pyramid texture, the technical requirements of the original mold were determined, and precision shaping planning technology was adopted to process the original mold. The shape error of the optical texture mold of the triangular pyramid was assessed by defining the area ratio of the retro-reflection. The influence of the tool nose radius and exit burr on the area ratio of the retro-reflection were analyzed. By optimizing the cutting tools, cutting materials and cutting boundaries, a five-axis ultra-precision machining system was used to plan the triangular pyramid structure with a base length of 115 µm and an included angle between two sides of 70.5°. The experimental results indicate that the dimension error of the triangular pyramid element is less than 1 µm, the angle error of the included angle between two sides is less than 0.05°, and the average roughness of the side of the triangular pyramid can reach 9.2 nm, which satisfies the processing quality requirements of the triangular pyramid texture mold.

11.
Environ Sci Pollut Res Int ; 25(20): 19836-19844, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29737483

RESUMO

Fertilizer regime is playing an important role in heavy metal cadmium (Cd) accumulation in paddy soils and crop plant. It is necessary to assess the Cd accumulation in soils and rice (Oryza sativa L.) plants under long-term fertilization managements, and the results which help to assess the environmental and food risk in Southern China. However, the effects of different organic manure and chemical fertilizers on Cd accumulation in soils and rice plant remain unclear under intensively cultivated rice conditions. Therefore, the objective was to explore Cd accumulation in paddy soils and rice plant at mature stage under different long-term fertilization managements in the double-cropping rice system. Cd accumulation in the surface soils (0-20 cm) and rice plant with chemical fertilizer alone (MF), rice straw residue and chemical fertilizer (RF), 30% organic matter and 70% chemical fertilizer (LOM), 60% organic matter and 40% chemical fertilizer (HOM), and without fertilizer input (CK) basis on 32 years long-term fertilization experiment were analyzed. The results showed that the soil total Cd content was increased by 0.296 and 0.351 mg kg-1 and 0.261 and 0.340 mg kg-1 under LOM and HOM treatments at early and late rice mature stages, respectively, compared with the CK treatment. And the soil available Cd content was increased by 0.073 and 0.137 mg kg-1 and 0.102 and 0.160 mg kg-1 under LOM and HOM treatments at early and late rice mature stages, respectively, compared with the CK treatment. The bioconcentration factor of Cd across different parts of rice plant was the highest in root, followed by stem and grain, and the lowest in leaves. At early and late rice mature stages, the root Cd concentration of rice plant was increased by 0.689 and 0.608 mg kg-1 with HOM treatment, the stem Cd concentration of rice plant was increased by 0.666 and 0.758 mg kg-1 with RF treatment, and the leaf and grain Cd concentration of rice plant was increased 0.094 and 0.082 mg kg-1 and 0.086 and 0.083 mg kg-1 with LOM treatment, respectively, compared with the CK treatment. The soil Cd single-factor contaminant index (PCd) under different fertilization treatments was as the following HOM > LOM > RF > MF > CK. Meanwhile, the PCd with LOM and HOM treatments was higher than that of the MF, RF, and CK treatments, but there is no significant difference between that of MF and RF treatments. Therefore, long-term application of rice straw residue and chemical fertilizer had no obvious effect on the accumulation of Cd in paddy soils and grain, and soil Cd accumulation was increased as application of organic fertilizer.


Assuntos
Cádmio/análise , Produção Agrícola/métodos , Fertilizantes/análise , Esterco/análise , Oryza/crescimento & desenvolvimento , Poluentes do Solo/análise , China , Oryza/química , Oryza/efeitos dos fármacos , Folhas de Planta/química , Caules de Planta/química , Solo/química , Fatores de Tempo
12.
ACS Appl Mater Interfaces ; 9(26): 21971-21978, 2017 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-28613809

RESUMO

Porous separators are key components for lithium-ion batteries (LIBs) and they have drawn considerable attention because of their vital role in governing battery cost and performance (e.g., power density, safety, and longevity). Here, zirconia-coated separators were fabricated via a facile biomineralization process with the aim to improve the performance of commercialized polypropylene separators. The as-prepared organic-inorganic composite separators show excellent thermal stability, even at the melting temperature (160 °C) of polypropylene. This is due to the well-distributed zirconia coatings on the separator surfaces. Furthermore, the interfacial impedance of the composite separators is only 343.8 Ω, which is four times lower than the pristine polypropylene ones. The results demonstrate an attractive method to prepare organic-inorganic composite separators with outstanding properties, which makes them promising candidates for high-performance LIBs.

13.
J Diabetes Res ; 2017: 2835981, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28713833

RESUMO

OBJECTIVE: To investigate the relationship between hemoglobin levels and diabetic peripheral neuropathy (DPN) in type 2 diabetes mellitus (T2DM). METHODS: 1511 patients with T2DM were included in the study. DPN was diagnosed based on symptoms, signs, and laboratory tests. Hemoglobin was defined as both a continuous variable and a quartile category variable. We compared patient characteristics between the no diabetic peripheral neuropathy (NDPN) and DPN groups. Logistic regression was conducted to investigate the association of DPN with hemoglobin in all T2DM patients. Linear regression was also performed to investigate the impact of hemoglobin on the vibrating perception threshold (VPT). RESULTS: Compared with the NDPN group, hemoglobin level in the DPN group was significantly lower (118.54 ± 16.91 versus 131.62 ± 18.32 g/L, P < 0.01). The prevalence of DPN increased by 50.1% (95% CI: 42.2-57.0%; P < 0.001) per standard deviation decrease in hemoglobin. Compared to the highest quartile of hemoglobin, the lower quartiles were associated with a significantly increased risk of DPN in the entire T2DM population (all P < 0.01). A per unit decrease in hemoglobin leads to a 0.12 (95% CI: 0.07-0.168) unit increase in VPT after adjustment for possible confounders (P < 0.001). CONCLUSIONS: Lower hemoglobin levels were associated with increased prevalence of DPN and higher VPT.


Assuntos
Diabetes Mellitus Tipo 2/sangue , Neuropatias Diabéticas/sangue , Hemoglobinas/análise , Idoso , Estudos Transversais , Diabetes Mellitus Tipo 2/epidemiologia , Neuropatias Diabéticas/epidemiologia , Registros Eletrônicos de Saúde , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Fatores de Risco
14.
Acta Diabetol ; 54(12): 1091-1099, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28918492

RESUMO

AIMS: Inflammation has been reported to be involved in the pathogenesis of atherosclerosis. This principal objective of this study was to investigate if the secretion of neuregulin 4 (Nrg4), a soluble protein associated with metabolic syndrome and subclinical cardiovascular disease, is correlated with the inflammation marker high-sensitivity C-reactive protein (hs-CRP) in patients with newly diagnosed type 2 diabetes mellitus (nT2DM). METHODS: A study group of 311 nT2DM patients was divided into three subgroups based on hs-CRP tertiles. Multiple linear regression was conducted to explore the association between plasma Nrg4 and hs-CRP levels. RESULTS: The nT2DM patients with the highest hs-CRP levels (>2.46 mg/L) exhibited higher atherogenic coefficients and atherogenic index of plasma (AIP) levels, but lower levels of plasma Nrg4, as compared to those with the lowest hs-CRP levels (<0.63 mg/L). Plasma Nrg4 levels were inversely associated with white blood cell count, hs-CRP, and AIP and positively associated with high-density lipoprotein cholesterol (HDL-C), before and after adjustment for age, gender, body mass index (BMI), and body fat percentage (P < 0.01 or P < 0.05). hs-CRP was the factor most strongly associated with plasma Nrg4 levels. CONCLUSIONS: These results indicate that lower plasma Nrg4 levels may be associated with elevated hs-CRP in nT2DM patients. It generates the hypothesis that decreased levels of Nrg4 may trigger the development of atherosclerosis through its proinflammatory effects. These findings need to be confirmed by further prospective studies.


Assuntos
Proteína C-Reativa/metabolismo , Diabetes Mellitus Tipo 2/sangue , Neurregulinas/sangue , Adulto , Idoso , Biomarcadores/sangue , Índice de Massa Corporal , HDL-Colesterol/sangue , Estudos Transversais , Diabetes Mellitus Tipo 2/diagnóstico , Feminino , Humanos , Contagem de Leucócitos , Masculino , Síndrome Metabólica/metabolismo , Pessoa de Meia-Idade
15.
ACS Appl Mater Interfaces ; 6(15): 12566-72, 2014 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-24998407

RESUMO

Silica-decorated polypropylene microfiltration membranes were fabricated via a facile biomimetic silicification process on the polydopamine/polyethylenimine-modified surfaces. The membranes exhibit superhydrophilicity and underwater superoleophobicity derived from the inherent hydrophilicity and the well-defined micronanocomposite structures of the silica-decorated surfaces. They can be applied in varieties of oil-in-water emulsions separation with high permeate flux (above 1200 L/m(2)h under 0.04 MPa) and oil rejection (above 99%). The membranes also have relatively high oil breakthrough pressure reaching 0.16 MPa due to the microporous structure, showing great potential for practical applications. Furthermore, such mussel-inspired intermediate layer provides us a convenient and powerful tool to fabricate organic-inorganic hybrid membranes for advanced applications.


Assuntos
Bivalves/química , Membranas Artificiais , Óleos/química , Polipropilenos/química , Dióxido de Silício/química , Ultrafiltração/métodos , Água/química , Animais , Emulsões , Indóis/química , Permeabilidade , Espectroscopia Fotoeletrônica , Polietilenoimina/química , Polímeros/química
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