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4.
ChemSusChem ; : e202400987, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38818947

RESUMEN

Covalent organic frameworks (COFs) are one type of promising polymer semiconductors in solar-driven hydrogen production, but majority of COFs-based photocatalytic systems show low photocatalytic efficiency owing to lack of metal active sites. Herein, we reported II-Scheme heterojunction frameworks based on COF (TpPa-1) and metal-organic framework (HKUST-1) for highly efficient hydrogen production. The coordination bonding directed self-assembly of HKUST-1 on the surface of TpPa-1 endows the heterojunction frameworks (HKUST-1/TpPa-1) with strong interface interaction, optimized electronic structures and abundant redox active sites, thus remarkably boosting photocatalytic hydrogen evolution. The hydrogen evolution rate for optimal HKUST-1/TpPa-1 is as high as 10.50 mmol g-1 h-1, which is significantly enhanced when compared with that of their physical mixture (4.13 mmol g-1 h-1), TpPa-1 (0.013 mmol g-1 h-1) and Pt-based counterpart (6.70 mmol g-1 h-1). This work offers a facile approach to the construction of noble-metal-free II-Scheme heterojunctions based on framework materials for efficient solar energy conversion.

8.
Front Physiol ; 15: 1359476, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38595644

RESUMEN

Background: Exercise has been reported to be associated with a reduced risk of nonalcoholic fatty liver disease (NAFLD), but there is no consensus on the role of weight changes in this association. This study aims to investigate whether the impact of exercise on NAFLD is mainly dependent on weight changes or is inherent to exercise itself. Methods: The study recruited 1671 Chinese NAFLD-free adults in 2019, and collected their exercise habits as well as 3 years of medical examination data including anthropometric measurements, blood biochemistry parameters, and liver ultrasound results. Univariate and multivariate logistic regression models were employed to examine the impact of exercise habits on NAFLD risk, with mediation analysis utilized to estimate the magnitude of the role of weight maintenance in the association between exercise and NAFLD. Results: After adjusting for confounders, moderate to high-intensity exercisers were 1.56 times (95% CIs = 1.09-2.22) more likely to successfully control their body weight, and therefore the weight-controlled group had a lower NAFLD risk of 34.9% (95% CIs = 21.8%-56.0%) compared to the weight-gain group. Mediation analysis reveals that exercise can significantly reduce the risk of NAFLD both through weight maintenance (37.1%) and independent of weight maintenance (62.9%). Conclusion: It might be more crucial to emphasize the adoption of regular moderate to high-intensity exercise for preventing NAFLD in the general population, rather than solely focusing on weight maintenance.

9.
Polymers (Basel) ; 16(7)2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38611198

RESUMEN

The fabrication of sustainable structural materials with high physical properties to replace engineering plastics is a major challenge for modern industry, and wood, as the most abundant sustainable natural raw material on the planet, has received a great deal of attention from researchers. Researchers have made efforts to enhance the physical properties of wood in order to replace plastics. However, it is also difficult to meet practical demands at a low cost. Herein, we report a simple and efficient top-down strategy to transform bulk natural basswood into a high-performance structural material. This three-step strategy involves partial removal of hemicellulose and lignin via treating basswood by boiling an aqueous mixture of NaOH and Na2SO3, and a high-pressure steam treatment (HPST) was applied to delignified wood followed by hot-pressing, which allowed the wood to absorb moisture uniformly and quickly. HPST-treated dense delignified wood (HDDW) has a tensile strength of ~420 MPa, which is 6.5 times better than natural basswood (~65 MPa). We systematically investigated the various factors affecting the tensile strength of this wood material and explored the reasons why these factors affect the tensile strength, as well as the intrinsic connection between the moisture absorbed through HPST and the increased tensile strength of HDDW. Through our experiments, we realized the enhancement mechanism of HDDW and the optimal experimental conditions for the fabrication of HDDW.

10.
Angew Chem Int Ed Engl ; 63(20): e202402881, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38433093

RESUMEN

Functionalized with the Au-S bond, gold nanoflares have emerged as promising candidates for theranostics. However, the presence of intracellular abundantly biothiols compromises the conventional Au-S bond, leading to the unintended release of cargoes and associated side-effects on non-target cells. Additionally, the hypoxic microenvironment in diseased regions limits treatment efficacy, especially in photodynamic therapy. To address these challenges, high-fidelity photodynamic nanoflares constructed on Pt-coated gold nanoparticles (Au@Pt PDNF) were communicated to avoid false-positive therapeutic signals and side-effects caused by biothiol perturbation. Compared with conventional photodynamic gold nanoflares (AuNP PDNF), the Au@Pt PDNF were selectively activated by cancer biomarkers and exhibited high-fidelity phototheranostics while reducing side-effects. Furthermore, the ultrathin Pt-shell catalysis was confirmed to generate oxygen which alleviated hypoxia-related photodynamic resistance and enhanced the antitumor effect. This design might open a new venue to advance theranostics performance and is adaptable to other theranostic nanomaterials by simply adding a Pt shell.


Asunto(s)
Antineoplásicos , Oro , Nanopartículas del Metal , Platino (Metal) , Nanomedicina Teranóstica , Oro/química , Humanos , Platino (Metal)/química , Nanopartículas del Metal/química , Antineoplásicos/química , Antineoplásicos/farmacología , Fotoquimioterapia , Supervivencia Celular/efectos de los fármacos , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/farmacología , Línea Celular Tumoral , Ensayos de Selección de Medicamentos Antitumorales , Proliferación Celular/efectos de los fármacos
12.
Quant Imaging Med Surg ; 13(4): 2376-2387, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-37064406

RESUMEN

Background: With the rapid development of shear wave elastography technology, the clinical application prospect of two-dimensional shear wave elastography (2D SWE) for non-invasive monitoring of liver fibrosis is extremely promising. This study aimed to evaluate the diagnostic performance of ElastQ, a noval 2D SWE method, in the staging of liver fibrosis in patients with chronic hepatitis B with histopathological results as the reference standard. Methods: Between August 2020 and December 2021, a prospective multicenter study of 602 consecutive patients with chronic hepatitis B was conducted in 14 hospitals. All patients underwent liver biopsy and 2D SWE examination. The patients were divided into a training cohort and a validation cohort. The area under the receiver operating characteristic curve (AUROC) was calculated, and the optimal cut-off values for ElastQ were obtained. Results: Overall, 2D SWE values showed a strong correlation with fibrosis stage (r=0.71, P<0.001). In the training cohort, the AUROCs of ElastQ for diagnosing fibrosis stages ≥S1, ≥S2, ≥S3, and S4 were 0.817 [95% confidence interval (CI): 0.777-0.853), 0.887 (95% CI: 0.852-0.915), 0.912 (95% CI: 0.881-0.937), and 0.832 (95% CI: 0.793-0.866)], respectively. In the validation cohort, the AUROCs of ElastQ for diagnosing fibrosis stages ≥S1, ≥S2, ≥S3, and S4 were 0.807 (95% CI: 0.742-0.861), 0.868 (95% CI: 0.810-0.914), 0.855 (95% CI: 0.796-0.903), and 0.851 (95% CI: 0.791-0.900), respectively. The optimal liver stiffness cut-off values for the identification of fibrosis stages ≥S1, ≥S2, ≥S3, and S4 were 5.72 kPa (sensitivity: 78%, specificity: 70%), 6.85 kPa (sensitivity: 77%, specificity: 86%), 7.43 kPa (sensitivity: 80%, specificity: 86%), and 8.03 kPa (sensitivity: 81%, specificity: 73%), respectively. Conclusions: Two-dimensional SWE can accurately stage liver fibrosis in patients with chronic hepatitis B.

14.
J Affect Disord ; 329: 157-167, 2023 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-36841306

RESUMEN

BACKGROUND: Globally, child maltreatment has become a serious problem, affecting individuals' physical and mental health. This meta-analysis aimed to explore the association between child maltreatment and social anxiety. METHODS: MEDLINE, PsycINFO, EMBASE, Scopus, and Web of Science were searched for articles published by October 2021. Newcastle-Ottawa Quality Assessment Scale (NOS) was used to evaluate the quality of studies. Maltreatment type, sample setting, age, country and measurement instruments were analyzed as moderators. RESULTS: Twenty-nine studies met the inclusion criteria. Child maltreatment was positively correlated with social anxiety (r = 0.201, 95 % CI [0.171, 0.230]). The moderating effect of maltreatment subtypes was significant whether divided into three types (Qb = 12.152, p = .002), or five types (Qb = 11.574, p = .021). Specifically, emotional maltreatment (r = 0.251, 95 % CI [0.201, 0.298]) had a stronger relationship with social anxiety than physical (r = 0.138, 95 % CI [0.085, 0.191]; Qb = 9.312, p = .002) and sexual maltreatment (r = 0.153, 95 % CI [0.108, 0.197]; Qb = 9.197, p = .002). However, there was no significant difference in the effect size between physical and sexual maltreatment (Qb = 0.096, p = .757). Other variables (age, sample setting and country) were not significant moderators. LIMITATIONS: Only twenty-nine studies were included, and there was high heterogeneity among the studies, the interpretation of the results should be cautious. CONCLUSIONS: This meta-analysis confirmed the relationship between child maltreatment and social anxiety, especially highlight the harmfulness of emotional maltreatment.


Asunto(s)
Maltrato a los Niños , Niño , Humanos , Maltrato a los Niños/psicología , Salud Mental , Tiempo , Ansiedad
16.
Front Psychol ; 13: 895117, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36033022

RESUMEN

This study adapts a Medical English Language Anxiety Scale (MELAS) based on Horwitz's Foreign Language Classroom Anxiety Scale (FLCAS) and examines students' anxiety in medical English vocabulary, listening and speaking, communication, literature reading, and academic paper writing. The biographical factors related to medical English language anxiety (MELA) were also tested. The questionnaire sets including five dimensions were distributed to the students from a medical university in Sichuan, China, and were statistically analyzed by using SPSS 22.0 and AMOS 21.0. By employing the adapted MELAS, it was found that 85.2% of the medical students surveyed suffered moderate and higher anxiety. Among all dimensions, students with listening and speaking anxiety recorded the highest (89.3%), followed by literature reading anxiety (86.6%), English academic writing anxiety (85.9%), communication anxiety (81.9%), and vocabulary learning anxiety (81.2%). We also found that the anxiety of rural medical students in each dimension was higher than that of urban medical students. This study suggests that English teachers should be fully aware of their students' language anxiety situation, design interesting class activities, and create a relaxed English learning atmosphere in classroom teaching to make students less nervous when learning medical English in class.

17.
Front Pediatr ; 10: 886031, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35573965

RESUMEN

Facial artery pseudoaneurysms are rare and mostly a result of blunt injury. Since the facial arteries are well protected by facial soft tissue and the lumen of the facial artery is thin and small in diameter, a sharp injury usually leads to complete transection rather than partial laceration of the blood vessel. As a non-invasive method, ultrasound does not involve radiation and sedation. Diagnosis of facial artery pseudoaneurysms is most commonly made with ultrasound, and Doppler ultrasound is essential. On grayscale imaging, facial artery pseudoaneurysms often appearanced of a fluid collection, Color Doppler imaging often show a well-defined swirl pattern named "yin and yang sign," the Spectral Doppler showed a diagnostic "to and fro" two-phase bidirectional arterial blood flow spectrum. It's particularly for the examination of facial artery pseudoaneurysms in children. Here, we report a case of facial foreign body abscess and facial artery pseudoaneurysm in a 19-month-old child 1 week after a sharpness injury that was diagnosed by ultrasound.

18.
J Phys Condens Matter ; 33(22)2021 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-33596556

RESUMEN

Two-dimensional (2D) Dirac materials have attracted intense research efforts due to their promise for applications ranging from field-effect transistors and low-power electronics to fault-tolerant quantum computation. One key challenge is to fabricate 2D Dirac materials hosting Dirac electrons. Here, monolayer germanene is successfully fabricated on a Ag2Ge surface alloy. Scanning tunneling spectroscopy measurements revealed a linear energy dispersion relation. The latter was supported by density functional theory calculations. These results demonstrate that monolayer germanene can be realistically fabricated on a Ag2Ge surface alloy. The finding opens the door to exploration and study of 2D Dirac material physics and device applications.

19.
PeerJ ; 8: e8811, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32219033

RESUMEN

BACKGROUND: The preoperative controlling nutritional status (CONUT) score and serum carbohydrate antigen 199 (CA199) levels are individually correlated with the prognosis of pancreatic ductal adenocarcinoma (PDAC). The objective of this study aimed to investigate the efficacy of CONUT score and CA199 (CONUT-CA199) combination in predicting the prognosis of PDAC patients undergoing radical surgery. METHODS: We retrospectively analyzed the preoperative CONUT scores and serum CA199 levels of 294 patients with PDAC who underwent radical resection at the Affiliated Hospital of Southwest Medical University between March 2012 and July 2019. Patients were divided into four groups on the basis of their preoperative CONUT scores and serum CA199 levels: CONUTlow/CA199low (1), CONUTlow/CA199high (2), CONUThigh/CA199low (3) and CONUThigh/CA199high (4). The prognostic effects were compared among the groups. RESULTS: CONUThigh was more frequent in patients with positive peripancreatic infiltration and Clavien-Dindo classification of ≥IIIa (P < 0.001). Kaplan-Meier analysis revealed obvious difference in overall survival (OS) and recurrence-free survival (RFS) among patients with PDAC having CONUT-CA199 scores of 1, 2, 3 and 4 (P < 0.001). Peripancreatic infiltration, lymph node metastasis, pTNM stage, CONUT score, serum CA199 levels and CONUT-CA199 classification were found to be the independent prognostic factors for OS and RFS in multivariate analyses. In time-dependent receiver operating characteristic (ROC) analyses, the area of the CONUT-CA199 score under the ROC curve (AUC) was higher than that of the preoperative CONUT score or serum CA199 levels for the prediction of OS and RFS. CONCLUSION: CONUT-CA199 classification may be more effective in predicting the postoperative prognosis of PDAC patients.

20.
Environ Sci Pollut Res Int ; 26(23): 23471-23479, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31197672

RESUMEN

A rapid and sensitive immunoassay for the simultaneous detection of imidacloprid and thiacloprid was developed by using magnetic nanoparticles (MNPs) and upconversion nanoparticles (UCNPs). The UCNPs of NaYF4:Yb, Er and NaYF4:Yb, Tm were synthesized and conjugated with anti-imidacloprid monoclonal antibody (mAb) and anti-thiacloprid mAb as signal labels, while the MNPs were conjugated with antigens of thiacloprid and imidacloprid as separation elements. The fluorescence intensities of Yb/Er- and Yb/Tm-doped UCNPs were detected simultaneously in 544 nm and 477 nm under the excitation of NIR light (980 nm). The amounts of mAb-conjugated UCNPs that were separated by antigen-conjugated MNPs were determined based on competitive immunoassays. Under the optimal conditions, the 50% inhibiting concentration (IC50) and limit of detection (LOD, IC10) were 5.80 and 0.32 ng/mL for imidacloprid and 6.45 and 0.61 ng/mL for thiacloprid, respectively. The immunoassay exhibited negligible cross-reactivity with analogs of imidacloprid and thiacloprid except imidaclothiz (86.2%). The average recoveries of imidacloprid and thiacloprid in environmental and agricultural samples, including paddy water, soil, pears, oranges, cucumbers, and wheat, ranged from 78.4 to 105.9% with relative standard deviations (RSDs) of 2.1-11.9% for imidacloprid and ranged from 82.5 to 102.3% with RSDs of 1.0-16.5% for thiacloprid. In addition, the results of the immunoassay correlated well with high-performance liquid chromatography for the detection of the authentic samples.


Asunto(s)
Inmunoensayo/métodos , Nanopartículas de Magnetita/química , Neonicotinoides/análisis , Nitrocompuestos/análisis , Tiazinas/análisis , Fluorescencia , Magnetismo , Nanopartículas/química , Tiazoles
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