Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 47
Filtrar
1.
Eur J Nutr ; 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38693449

RESUMEN

OBJECTIVE: To compare the outcomes associated with the use of probiotics, prebiotics, and synbiotics for the treatment of chronic constipation in adults. METHODS: We searched eight electronic databases from database inception to July 11, 2023, to identify randomized controlled trials (RCTs) that report efficacy and safety for the treatment of chronic constipation. The risk of bias in the included RCTs was evaluated according to the Cochrane tool, and the certainty of the evidence was assessed using the Confidence in Network Meta-Analysis framework. The analysis was conducted using R version 4.3.0. RESULTS: Out of the 37 RCTs, a total of 21 different types of interventions were reported, involving 3,903 patients. This NMA demonstrated that both prebiotics and synbiotics resulted in an increase in frequency of stool movements per week. Compared to placebo, lactulose (Mean difference [MD] = 3.39, 95% Confdence interval [CI] [1.13, 5.65], moderate certainty), mix2 (consisting of Lactulose and Bacillus coagulans) (MD = 3.63, 95% CI [1.37, 5.89], moderate certainty), mix6 (consisting of Lactulose and Bifidobacterium coagulans) (MD = 4.30, 95% CI [1.04, 7.54], low certainty), and mix7 (consisting of Lactulose, Bifidobacterium subtilis, and Enterococcus faecium) (MD = 4.58, 95% CI [1.35, 7.78], moderate certainty) exhibited a significant effect. Notably, mix7 demonstrated the highest probability of being the most effective intervention (94.8%). Furthermore, when compared to L. plantarum, four probiotics and two synbiotics showed significant advantages in the Patient Assessment of Constipation Symptoms (PAC-SYM) score. L. reuteri (MD = -13.74, 95% CI [-22.20, -4.66], very low certainty) exhibited a significant effect in improving the Patient Assessment of Constipation Quality of Life (PAC-QoL) score. In terms of safety, there were no statistically significant differences between the intervention and control groups in all adverse event analyses. CONCLUSIONS: Moderate to very low evidence supports the use of lactulose and synbiotics to increase the number of weekly stool movements in patients, particularly highlighting the significant impact of synbiotics in increasing the number of weekly stool movements in patients with constipation. The use of L. paracasei showed improvements in PAC-SYM scores, while L. reuteri demonstrated enhancements in PAC-QoL scores.

2.
Sci Data ; 11(1): 310, 2024 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-38521796

RESUMEN

Wetlands play a key role in maintaining ecological balance and climate regulation. However, due to the complex and variable spectral characteristics of wetlands, there are no publicly available global 30-meter time-series wetland dynamic datasets at present. In this study, we present novel global 30 m annual wetland maps (GWL_FCS30D) using time-series Landsat imagery on the Google Earth Engine platform, covering the period of 2000-2022 and containing eight wetland subcategories. Specifically, we make full use of our prior globally distributed wetland training sample pool, and adopt the local adaptive classification and spatiotemporal consistency checking algorithm to generate annual wetland maps. The GWL_FCS30D maps were found to achieve an overall accuracy and Kappa coefficient of 86.95 ± 0.44% and 0.822, respectively, in 2020, and show great temporal variability in the United States and the European Union. We expect the dataset would provide vital support for wetland ecosystems protection and sustainable development.


Asunto(s)
Ecosistema , Humedales , Clima , Monitoreo del Ambiente
3.
J Headache Pain ; 25(1): 16, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38311738

RESUMEN

OBJECTIVE: To compare the outcomes associated with the use of lasmiditan, rimegepant, ubrogepant, and zavegepant for the acute management of migraine headaches. METHODS: We searched four electronic databases from database inception to August 31, 2023, to identify randomized controlled trials (RCTs) that report efficacy and safety for the acute treatment of migraine. The risk of bias in the included RCTs was evaluated according to the Cochrane tool, and the certainty of evidence using the CINeMA approach. We conducted frequentist network meta-analyses (NMA) to summarise the evidence. Data were analyzed using R-4.3.1. RESULTS: A total of 18 eligible studies including 10 different types of interventions with 22,429 migraine patients were included. NMA results showed that compared to ubrogepant (25 mg and 50 mg) and zavegepant, lasmiditan (100 mg and 200 mg) exhibits an elevated probability of achieving pain relief within a 2-hour interval. Similarly, relative to zavegepant, rimegepant (75 mg) and ubrogepant (50 mg and 100 mg) demonstrate an enhanced likelihood of sustaining pain relief over a 24-hour period. Furthermore, in contrast to ubrogepant (25 mg) and lasmiditan (50 mg), rimegepant (75 mg) presents a heightened probability of achieving freedom from photophobia within 2 h. Regarding safety, lasmiditan carries the highest risk of adverse events, which are associated with an increased incidence of adverse effects, including dizziness, somnolence, asthenia, paresthesia, and fatigue. CONCLUSIONS: In this NMA, a spectrum of evidence ranging from very low to high levels underscores the favorable efficacy and tolerability of rimegepant 75 mg and ubrogepant 100 mg, positioning them as potential candidates for the acute management of migraine. Concurrently, lasmiditan (100 mg and 200 mg) exhibits notable efficacy, albeit accompanied by an increased susceptibility to adverse events. These findings should still be approached with caution, primarily due to the intrinsic limitations associated with indirect comparisons.


Asunto(s)
Benzamidas , Péptido Relacionado con Gen de Calcitonina , Trastornos Migrañosos , Piperidinas , Piridinas , Adulto , Humanos , Benzamidas/uso terapéutico , Péptido Relacionado con Gen de Calcitonina/antagonistas & inhibidores , Trastornos Migrañosos/tratamiento farmacológico , Metaanálisis en Red , Dolor , Piperidinas/uso terapéutico , Piridinas/uso terapéutico , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del Tratamiento
4.
Nano Lett ; 24(3): 1034-1043, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38190456

RESUMEN

Interfacial solar vapor generation holds great promise for alleviating the global freshwater crisis, but its real-world application is limited by the efficiently choppy water evaporation and industrial production capability. Herein, a self-floating solar evaporator with an underwater aerophilic surface is innovatively fabricated by weaving core-shell yarns via mature weaving techniques. The core-shell yarns possess capillary water channels in the hydrophilic cotton core and can trap air in the hydrophobic electrospinning nanofiber shell when submerged underwater, simultaneously realizing controllable water supplies, stable self-flotation, and great thermal insulation. Consequently, the self-floating solar evaporator achieves an evaporation rate of 2.26 kg m-2 h-1 under 1 sun irradiation, with a reduced heat conduction of 70.18 W m-2. Additionally, for the first time, a solar evaporator can operate continuously in water with varying waveforms and intensities over 24 h, exhibiting an outdoor cumulative evaporation rate of 14.17 kg m-2 day-1.

5.
Clin Exp Metastasis ; 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38261139

RESUMEN

Antigen-presenting cells (APCs) are pivotal mediators of immune responses. Their role has increasingly been spotlighted in the realm of cancer immunology, particularly as our understanding of immunotherapy continues to evolve and improve. There is growing evidence that these cells play a non-trivial role in cancer immunity and have roles dependent on surface markers, growth factors, transcription factors, and their surrounding environment. The main dendritic cell (DC) subsets found in cancer are conventional DCs (cDC1 and cDC2), monocyte-derived DCs (moDC), plasmacytoid DCs (pDC), and mature and regulatory DCs (mregDC). The notable subsets of monocytes and macrophages include classical and non-classical monocytes, macrophages, which demonstrate a continuum from a pro-inflammatory (M1) phenotype to an anti-inflammatory (M2) phenotype, and tumor-associated macrophages (TAMs). Despite their classification in the same cell type, each subset may take on an immune-activating or immunosuppressive phenotype, shaped by factors in the tumor microenvironment (TME). In this review, we introduce the role of DCs, monocytes, and macrophages and recent studies investigating them in the cancer immunity context. Additionally, we review how certain characteristics such as abundance, surface markers, and indirect or direct signaling pathways of DCs and macrophages may influence tumor response to immune checkpoint blockade (ICB) therapy. We also highlight existing knowledge gaps regarding the precise contributions of different myeloid cell subsets in influencing the response to ICB therapy. These findings provide a summary of our current understanding of myeloid cells in mediating cancer immunity and ICB and offer insight into alternative or combination therapies that may enhance the success of ICB in cancers.

6.
Eur J Clin Nutr ; 78(3): 171-179, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38093096

RESUMEN

A dramatic shift in the global food system is occurring with the rapid growth of ultra-processed foods (UPFs) consumption, which poses potentially serious health risks. Systematic review (SR) method has been used to summarise the association between UPF consumption and multiple health outcomes; however, a suboptimal-quality SR may mislead the decision-making in clinical practices and health policies. Therefore, a methodological review was conducted to identify the areas that can be improved regarding the risk of bias and reporting quality of relevant SRs. Systematic searches to collect SRs with meta-analyses of UPFs were performed using four databases from their inception to April 14, 2023. The risk of bias and reporting quality were evaluated using ROBIS and PRISMA 2020, respectively. The key characteristics of the included SRs were summarised descriptively. Excel 2019 and R 4.2.3 were used to analyse the data and draw graphs. Finally, 16 relevant SRs written in English and published between 2020 and 2023 in 12 academic journals were included. Only one SR was rated as low risk of bias, and the others were rated as higher risk of bias mainly because the risk of bias in the original studies was not explicitly addressed when synthesising the evidence. The reporting was required to be advanced significantly, involving amendments of registration and protocol, data and analytic code statement, and lists of excluded studies with justifications. The reviews' results could improve the quality, strengthen future relevant SRs' robustness, and further underpin the evidence base for supporting clinical decisions and health policies.


Asunto(s)
Alimentos Procesados , Proyectos de Investigación , Humanos , Sesgo
7.
Clin Exp Metastasis ; 2023 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-38064127

RESUMEN

Cancer is a disease that undergoes selective pressure to evolve during its progression, becoming increasingly heterogeneous. Tumoral heterogeneity can dictate therapeutic response. Transcriptomics can be used to uncover complexities in cancer and reveal phenotypic heterogeneity that affects disease response. This is especially pertinent in the immune microenvironment, which contains diverse populations of immune cells, and whose dynamic properties influence disease response. The recent development of immunotherapies has revolutionized cancer therapy, with response rates of up to 50% within certain cancers. However, despite advances in immune checkpoint blockade specifically, there remains a significant population of non-responders to these treatments. Transcriptomics can be used to profile immune and other cell populations following immune-checkpoint inhibitor (ICI) treatment, generate predictive biomarkers of resistance or response, assess immune effector function, and identify potential immune checkpoints. Single-cell RNA sequencing has offered insight into mRNA expression within the complex and heterogeneous tumor microenvironment at single-cell resolution. Spatial transcriptomics has enabled measurement of mRNA expression while adding locational context. Here, we review single-cell sequencing and spatial transcriptomic research investigating ICI response within a variety of cancer microenvironments.

8.
Front Pharmacol ; 14: 1282203, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37964867

RESUMEN

Tanshinone is a lipophilic compound that is present in traditional Chinese medicine and is derived from the roots of Salvia miltiorrhiza (Danshen). It has been proven to be highly effective in combating tumors in various parts of the body, including liver carcinoma, gastric cancer, ovarian cancer, cervix carcinoma, breast cancer, colon cancer, and prostate cancer. Tanshinone can efficiently prevent the reproduction of cancerous cells, induce cell death, and inhibit the spread of cancerous cells, which are mainly involved in the PI3K/Akt signaling pathway, NF-κB pathway, Bcl-2 family, Caspase cascades, MicroRNA, MAPK signaling pathway, p21, STAT3 pathway, miR30b-P53-PTPN11/SHP2 axis, ß-catenin, and Skp2. However, the properties and mechanisms of tanshinone's anti-tumor effects remain unclear currently. Thus, this study aims to review the research progress on tumor prevention and mechanisms of tanshinone to gain new perspectives for further development and clinical application of tanshinone.

9.
BMC Med ; 21(1): 378, 2023 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-37775745

RESUMEN

BACKGROUND: Although non-pharmacological smoking cessation measures have been widely used among smokers, current research evidence on the effects of smoking cessation is inconsistent and of mixed quality. Moreover, there is a lack of comprehensive evidence synthesis. This study seeks to systematically identify, describe, and evaluate the available evidence for non-pharmacological interventions in smoking populations through evidence mapping (EM), and to search for best-practice smoking cessation programs. METHODS: A comprehensive search for relevant studies published from the establishment of the library to January 8, 2023, was conducted in PubMed, Web of Science, Embase, the Cochrane Library, CNKI, CBM, Wan Fang, and VIP. Two authors independently assessed eligibility and extracted data. The PRISMA statement and AMSTAR 2 tool were used to evaluate the report quality and methodology quality of systematic reviews/meta-analyses (SRs/MAs), respectively. Bubble plots were utilized to display information, such as the study population, intervention type, evidence quality, and original study sample size. RESULTS: A total of 145 SRs/MAs regarding non-pharmacological interventions for smoking cessation were investigated, with 20 types of interventions identified. The most commonly used interventions were cognitive behaviour education (n = 32, 22.07%), professional counselling (n = 20, 13.79%), and non-nicotine electronic cigarettes (e-cigarettes) (n = 13, 8.97%). Among them, counselling and behavioural support can improve smoking cessation rates, but the effect varies depending on the characteristics of the support provided. These findings are consistent with previous SRs/MAs. The general population (n = 108, 74.48%) was the main cohort included in the SRs/MAs. The total score of PRISMA for the quality of the reports ranged from 8 to 27, and 13 studies (8.97%) were rated as high confidence, and nine studies (6.21%) as moderate confidence, in the AMSTAR 2 confidence rating. CONCLUSIONS: The abstinence effect of cognitive behaviour education and money incentive intervention has advantages, and non-nicotine e-cigarettes appear to help some smokers transition to less harmful replacement tools. However, the methodological shortcomings of SRs/MAs should be considered. Therefore, to better guide future practice in the field of non-pharmacological smoking cessation, it is essential to improve the methodological quality of SRs and carry out high-quality randomized controlled trials (RCTs).


Asunto(s)
Sistemas Electrónicos de Liberación de Nicotina , Cese del Hábito de Fumar , Humanos , Consejo , Fumar/epidemiología , Cese del Hábito de Fumar/métodos , Prevención del Hábito de Fumar , Revisiones Sistemáticas como Asunto , Metaanálisis como Asunto
10.
J Colloid Interface Sci ; 651: 633-644, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37562305

RESUMEN

Metal sulfide based photocatalysts are considered to be economic, environmentally benign and renewable. The rapid recombination of photogenerated electrons and holes and low solar energy utilization efficiency, however, remain a huge bottleneck. Herein, two-dimensional/two-dimensional (2D/2D) S-scheme WS2/Zn3In2S6 heterostructure with ultrathin nanosheets intervening between neighboring component has been designed. The large and intimate S-scheme heterojunctions facilitate interfacial charge separation/transfer and optimize the available redox potential. Besides, the ultrathin 2D/2D heterostructure ensures large specific surface area, maximized interface synergistic interaction, and effective exposure of surface active sites. As a result, 2 wt% WS2/Zn3In2S6 exhibits a high photocatalytic hydrogen production rate of 30.21 mmol·g-1·h-1 under simulated solar light illumination with an apparent quantum efficiency of 56.1% at 370 nm monochromatic light, far exceeding pristine Zn3In2S6 (6.65 mmol·g-1·h-1). Our work underscores the significance of integrating morphology engineering and S-scheme heterojunctions design for high-efficient and low-cost photocatalysts.

11.
Nutrients ; 15(14)2023 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-37513612

RESUMEN

OBJECTIVE: The available evidence on selenium supplementation in the treatment of autoimmune thyroiditis (AIT) was inconclusive. This research serves to assess the effects of selenium supplementation in the treatment of AIT. METHODS: Online databases including PubMed, Web of Science, Embase, and the Cochrane Library were searched from inception to 10 June 2022. The AMSTAR-2 tool was used to assess the methodological quality of included studies. The information on the randomized controlled trials of the included studies was extracted and synthesized. The GRADE system was used to assess the certainty of evidence. RESULTS: A total of 6 systematic reviews with 75 RCTs were included. Only one study was rated as high quality. The meta-analysis showed that in the levothyroxine (LT4)-treated population, thyroid peroxidase antibody (TPO-Ab) levels decreased significantly in the selenium group at 3 months (SMD = -0.53, 95% CI: [-0.89, -0.17], p < 0.05, very low certainty) and 6 months (SMD = -1.95, 95% CI: [-3.17, -0.74], p < 0.05, very low certainty) and that thyroglobulin antibody (Tg-Ab) levels were not decreased. In the non-LT4-treated population, TPO-Ab levels decreased significantly in the selenium group at 3 and 6 months and did not decrease at 12 months. Tg-Ab levels decreased significantly in the selenium group at 3 and 6 months and did not decrease at 12 months. The adverse effects reported in the selenium group were not significantly different from those in the control group, and the certainty of evidence was low. CONCLUSION: Although selenium supplementation might reduce TPO-Ab levels at 3 and 6 months and Tg-Ab levels at 3 and 6 months in the non-LT4-treated population, this was based on a low certainty of evidence.


Asunto(s)
Enfermedad de Hashimoto , Selenio , Tiroiditis Autoinmune , Humanos , Tiroiditis Autoinmune/tratamiento farmacológico , Selenio/uso terapéutico , Yoduro Peroxidasa , Revisiones Sistemáticas como Asunto , Tiroxina , Suplementos Dietéticos
12.
Addict Biol ; 28(8): e13303, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37500482

RESUMEN

To evaluate the effectiveness, safety and tolerability of antidepressants in helping smokers quit tobacco dependence, five databases were searched for randomized controlled trials (RCTS ) on different antidepressant interventions involving smoking cessation in populations (September 2022). The STATA 15.1 software was used to perform network meta-analysis. The Cochrane bias risk tool was used to assess the risk of bias, and CINeMA was used to evaluate the evidence credibility for the effect of different interventions on smoking cessation. In all, 107 RCTs involving 42 744 patients were included. Seven studies were rated as having a low risk of bias. All trials reported 18 interventions and 153 pairwise comparisons were generated. The network meta-analysis showed that compared with placebo, varenicline + bupropion (OR = 3.53, 95% CI [2.34, 5.34]), selegiline + nicotine replacement therapy (NRT) (OR = 3.78, 95% CI [1.20, 11.92]), nortriptyline + NRT (OR = 2.33, 95% CI [1.21, 4.47), nortriptyline (OR = 1.58, 95% CI [1.11,2.26]), naltrexone + bupropion (OR = 3.84, 95% CI [1.39, 10.61]), bupropion + NRT (OR = 2.29, 95% CI [1.87, 2.81]) and bupropion (OR = 1.70, 95% CI [1.53, 1.89]) showed benefits with respect to smoking cessation. In addition, bupropion + NRT showed better effects than bupropion (OR = 1.35, 95% CI [1.12, 1.64]) and NRT (OR = 1.38, 95% CI [1.13, 1.69]) alone. The final cumulative ranking curve showed that varenicline + bupropion was the most likely to be the best intervention. There was moderate- to very-low-certainty evidence that most interventions showed benefits for smoking cessation compared with placebo, including monotherapy and combination therapies. Varenicline + bupropion had a higher probability of being the best intervention for smoking cessation.


Asunto(s)
Alcoholismo , Cese del Hábito de Fumar , Humanos , Cese del Hábito de Fumar/métodos , Bupropión/efectos adversos , Vareniclina/efectos adversos , Nortriptilina/efectos adversos , Metaanálisis en Red , Fumar , Dispositivos para Dejar de Fumar Tabaco , Antidepresivos/uso terapéutico , Alcoholismo/tratamiento farmacológico
13.
Polymers (Basel) ; 15(12)2023 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-37376279

RESUMEN

Plant fiber-reinforced composites have the advantages of environmental friendliness, sustainability, and high specific strength and modulus. They are widely used as low-carbon emission materials in automobiles, construction, and buildings. The prediction of their mechanical performance is critical for material optimal design and application. However, the variation in the physical structure of plant fibers, the randomness of meso-structures, and the multiple material parameters of composites limit the optimal design of the composite mechanical properties. Based on tensile experiments on bamboo fiber-reinforced, palm oil-based resin composites, finite element simulations were carried out and the effect of material parameters on the tensile performances of the composites was investigated. In addition, machine learning methods were used to predict the tensile properties of the composites. The numerical results showed that the resin type, contact interface, fiber volume fraction, and multi-factor coupling significantly influenced the tensile performance of the composites. The results of the machine learning analysis showed that the gradient boosting decision tree method had the best prediction performance for the tensile strength of the composites (R2 was 0.786) based on numerical simulation data from a small sample size. Furthermore, the machine learning analysis demonstrated that the resin performance and fiber volume fraction were critical parameters for the tensile strength of composites. This study provides an insightful understanding and effective route for investigating the tensile performance of complex bio-composites.

14.
J Am Chem Soc ; 145(22): 12255-12263, 2023 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-37246940

RESUMEN

Chiral metal nanoclusters have recently been attracting great attention. It is challenging to realize asymmetric catalysis via atomically precise metal nanoclusters. Herein, we report the synthesis and total structure determination of chiral clusters [Au7Ag8(dppf)3(l-/d-proline)6](BF4)2 (l-/d-Au7Ag8). Superatomic clusters l-/d-Au7Ag8 display intense and mirror-image Cotton effects in their CD spectra. Density functional theory (DFT) calculations were carried out to understand the correlation between electronic structures and the optical activity of the enantiomeric pair. Surprisingly, the incorporation of proline in a metal nanocluster can significantly promote the catalytic efficiency in asymmetric Aldol reactions. The increase of catalytic activity of Au7Ag8 in comparison with organocatalysis by proline is attributed to the cooperative effect of the metal core and prolines, showing the advantages of the integration of metal catalysis and organocatalysis in a metal nanocluster.

15.
J Colloid Interface Sci ; 640: 31-40, 2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-36827846

RESUMEN

Converting solar energy into hydrogen energy is a feasible means to solve the current energy crisis. However, developing an excellent photocatalyst with high light utilization and stability for hydrogen production remains a great challenge. In this work, CoS2 nanoparticles as cocatalysts are growth on Zn3In2S6 nanosheets with abundant sulfur vacancies for hydrogen evolution, and the optimal rate of hydrogen evolution is as high as 5.69 mmol h-1 g-1 in the absence of noble metal co-catalyst Pt, which is 2.87 and 2.29 times that of CoS2/Zn3In2S6 (with few sulfur vacancies) and Zn3In2S6 (with rich sulfur vacancies). In addition, the hydrogen production rate of CoS2/Zn3In2S6 composite (with rich sulfur vacancies and 1 wt% Pt) is 24.17 mmol h-1 g-1, which is 4.25 and 1.90 times that of CoS2/Zn3In2S6 (with rich sulfur vacancies) and 1%-Pt/Zn3In2S6 (with rich sulfur vacancies), respectively. The apparent quantum efficiency (AQE) of CoS2/Zn3In2S6 composite (with rich sulfur vacancies and 1 wt% Pt) reaches 66.20% under light irradiation at the wavelength of 370 nm. Above all indicate that dual cocatalysts (CoS2 and Pt) and sulfur vacancies can promote the efficient hydrogen evolution activity of Zn3In2S6 nanosheets. This work will provide new ideas and insights for the development of photocatalytic hydrogen production technology.

16.
ACS Appl Mater Interfaces ; 15(4): 5963-5973, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36650640

RESUMEN

The demands of safety and sustainability have driven the development of intrinsic flame-retardant biobased polymers from renewable materials. Herein, a mechanically robust, good flame-retardant, and recyclable thermoset was developed from renewable epoxidized soybean oil (ESO) by using 2-hydroxyethyl methacrylate phosphate (HEMAP) as the reactive flame retardant and tannic acid (TA) as the charring agent. The flame resistance of the obtained ESO-based thermoset achieved the highest UL-94 of V-0 rating and a limited oxygen index value of 26.7% due to the synergistic flame-retardant effect of phosphate and TA. The flame-retardant mechanisms of the gaseous phase and condensed phase were fully investigated by thermogravimetric infrared, scanning electron microscopy-energy-dispersive spectrometry, X-ray photoelectron spectroscopy, and Raman spectra. It is confirmed that the incorporation of phosphate and TA could effectively promote the formation of dense carbon layers and delay the pyrolysis of long aliphatic chains. The ternary crosslinking of ESO, HEMAP, and TA via free-radical polymerization and epoxy-ring opening reaction resulted in a rigid network with a high crosslink density, bestowing the thermoset with superior tensile strength (20.0 MPa), flexural strength (36.3 MPa), and bonding strength (16.7 MPa on steel). Moreover, the ESO-based thermoset exhibited a fast stress relaxation behavior due to the transesterification of dynamic ß-hydroxyl phosphate esters, which enables the network with thermal-healing ability and recyclability. This study explores a feasible method to prepare an intrinsic flame-retardant polymer from commercially available and renewable vegetable oils and natural polyphenols.

17.
Dig Liver Dis ; 55(8): 1133-1140, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36642562

RESUMEN

BACKGROUND: Recently, some studies have suggested a link between AQP1 and cancer progression. AIMS: The aim of the present study was to investigate the influence of AQP1 on the clinicopathology and prognosis of intrahepatic cholangiocarcinoma (ICC) patients. METHODS: We retrospectively detected the expression of AQP1 protein in 307 patients with ICC who underwent partial hepatectomy. Western blot analysis was used to detect AQP1 protein levels in stable AQP1 overexpression and knockdown cell lines. The influence of AQP1 on the invasion and metastasis ability of ICC cells was assessed by wound-healing and Transwell assays in vitro as well as by a splenic liver metastasis model in vivo. RESULTS: Positive membranous AQP1 expression was identified in 34.2% (105/307) of the ICC specimens. Survival data revealed that positive AQP1 expression was significantly associated with favourable disease-free survival (DFS) and overall survival (OS) (p = 0.0290 and p = 0003, respectively). Moreover, high AQP1 expression inhibited the invasion and migration of ICC cells in vitro as well as inhibited liver metastasis in nude mice. Mechanistically, high AQP1 expression in ICC cells increased the levels of E-cadherin but decreased the levels of the Snail transcription factor. CONCLUSIONS: AQP1 expression is associated with a favourable prognosis in ICC patients. AQP1 inhibits ICC cell invasion, metastasis, and epithelial-mesenchymal transition (EMT) through downregulation of Snail expression.


Asunto(s)
Neoplasias de los Conductos Biliares , Colangiocarcinoma , Neoplasias Hepáticas , Animales , Ratones , Acuaporina 1/genética , Acuaporina 1/metabolismo , Neoplasias de los Conductos Biliares/genética , Neoplasias de los Conductos Biliares/cirugía , Neoplasias de los Conductos Biliares/metabolismo , Conductos Biliares Intrahepáticos/patología , Línea Celular Tumoral , Proliferación Celular , Colangiocarcinoma/genética , Colangiocarcinoma/cirugía , Colangiocarcinoma/metabolismo , Regulación hacia Abajo , Transición Epitelial-Mesenquimal , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/cirugía , Neoplasias Hepáticas/metabolismo , Ratones Desnudos , Pronóstico , Estudios Retrospectivos , Humanos
18.
J Colloid Interface Sci ; 637: 465-476, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36716670

RESUMEN

Semiconductor photocatalytic water splitting is a green way to convert solar energy into chemical energy, but the recombination of electron and hole pairs and the low utilization of sunlight restrict the development of photocatalytic technology. By comparing the morphologies and hydrogen production properties of different proportions of solid solutions (CdxZn1-xS), one-dimensional (1D) Cd0.9Zn0.1S nanorods (NRs) with the best photocatalytic properties are obtained. In addition, 1D W18O49 nanowires are assembled on the surface of 1D Cd0.9Zn0.1S NRs to construct a novel 1D/1D step-scheme (S-scheme) W18O49/Cd0.9Zn0.1S heterojunction photocatalyst. The W18O49/Cd0.9Zn0.1S heterojunction expands the optical absorption capacity of Cd0.9Zn0.1S NRs to provide more energy for the photoexcitation of electrons. The optimal hydrogen production rate of W18O49/Cd0.9Zn0.1S NRs with W18O49 content of 9 wt% is as high as 66.3 mmol·h-1·g-1, which is 5.7 times and 1.6 times higher than that of Cd0.9Zn0.1S NRs and 1 wt% Pt/Cd0.9Zn0.1S NRs. The apparent quantum efficiency (AQE) of 9 wt% W18O49/Cd0.9Zn0.1S reaches 56.0 % and 25.9 % under light wavelength irradiation at 370 and 456 nm, respectively. After the 20 h cycle stability test, the activity of photocatalytic hydrogen evolution does not decrease, due that the severe photo-corrosion of Cd0.9Zn0.1S NRs is efficiently inhibited. This work not only provides a simple and controllable synthesis method for the preparation of heterojunction structure, but also opens up a new way to improve the hydrogen evolution activity and stability of sulfur compounds.

19.
Chemistry ; 28(24): e202104445, 2022 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-35218267

RESUMEN

Surface organic ligands are critical in dictating the structures and properties of atomically precise metal nanoclusters. In contrast to the conventionally used thiolate, phosphine and alkynyl ligands, nitrogen donor ligands have not been used in the protection for well-defined metal nanoclusters until recently. This review focuses on recent developments in atomically precise metal nanoclusters stabilized by different types of nitrogen donor ligands, in which the synthesis, total structure determination and various properties are covered. We hope that this review will provide insights into the rational design of N donor-protected metal nanoclusters in terms of structural and functional modulation.

20.
J Am Chem Soc ; 143(31): 12261-12267, 2021 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-34324334

RESUMEN

The first linear silver supercluster based on icosahedral Ag13 units has been constructed via bridging of dpa ligands: Ag61(dpa)27(SbF6)4 (Hdpa = dipyridylamine) (Ag61). Single-crystal X-ray diffraction reveals that this rod-shaped cluster consists of four vertex-sharing Ag13 icosahedra in a linear arrangement. This Ag61 cluster represents the longest one-dimensional metal nanocluster with a resolved structure. Unprecedented electron coupling develops between their constituent Ag13 units. Theoretical studies disclose that the stabilities of the two superclusters are dictated by a strong interaction between the Ag13 units as well as the ligand effect of the dpa-Ag motifs. The quantum size effect accounts for the significant enhancement of the metal-related absorptions and the red shift at the near-infrared region as the length of the cluster increases. This work sheds light on the evolution of one-dimensional materials and an understanding of the electronic communication between the constituent clusters.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...