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1.
Nat Commun ; 15(1): 4636, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38821951

RESUMEN

The catalytic partial oxidation of methane (POM) presents a promising technology for synthesizing syngas. However, it faces severe over-oxidation over catalyst surface. Attempts to modify metal surfaces by incorporating a secondary metal towards C-H bond activation of CH4 with moderate O* adsorption have remained the subject of intense research yet challenging. Herein, we report that high catalytic performance for POM can be achieved by the regulation of O* occupation in the atomically dispersed (AD) MoNi alloy, with over 95% CH4 conversion and 97% syngas selectivity at 800 °C. The combination of ex-situ/in-situ characterizations, kinetic analysis and DFT (density functional theory) calculations reveal that Mo-Ni dual sites in AD MoNi alloy afford the declined O2 poisoning on Ni sites with rarely weaken CH4 activation for partial oxidation pathway following the combustion reforming reaction (CRR) mechanism. These results underscore the effectiveness of CH4 turnovers by the design of atomically dispersed alloys with tunable O* adsorption.

2.
Nat Commun ; 15(1): 2970, 2024 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-38582759

RESUMEN

Photoelectrochemical seawater splitting is a promising route for direct utilization of solar energy and abundant seawater resources for H2 production. However, the complex salinity composition in seawater results in intractable challenges for photoelectrodes. This paper describes the fabrication of a bilayer stack consisting of stainless steel and TiO2 as a cocatalyst and protective layer for Si photoanode. The chromium-incorporated NiFe (oxy)hydroxide converted from stainless steel film serves as a protective cocatalyst for efficient oxygen evolution and retarding the adsorption of corrosive ions from seawater, while the TiO2 is capable of avoiding the plasma damage of the surface layer of Si photoanode during the sputtering of stainless steel catalysts. By implementing this approach, the TiO2 layer effectively shields the vulnerable semiconductor photoelectrode from the harsh plasma sputtering conditions in stainless steel coating, preventing surface damages. Finally, the Si photoanode with the bilayer stack inhibits the adsorption of chloride and realizes 167 h stability in chloride-containing alkaline electrolytes. Furthermore, this photoanode also demonstrates stable performance under alkaline natural seawater for over 50 h with an applied bias photon-to-current efficiency of 2.62%.

3.
Chem Commun (Camb) ; 60(29): 3922-3925, 2024 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-38501201

RESUMEN

A systematic theoretical study probing the catalytic potential of metal-doped SnO2(110) was conducted. The incorporation of metals such as Zr, Ti, W, V, Hf, and Ge is shown to drive electron transfer to Sn. The increased charge of Sn is injected into anti-bonding orbitals, finely tuning the catalytic activity and reducing the overpotential to -0.34 V. AIMD simulations show the stability of the modified structures. This work sheds light on the rational design of low-cost metal oxides with a high catalytic performance for CO2ER to formate.

4.
Mol Cell Probes ; 75: 101958, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38518900

RESUMEN

OBJECTIVE: The effects of mesenchymal stem cells (MSCs) and MSC-derived exosomes (MSC-exos) on serum metabolites and intestinal microbiota in rats after liver trauma were discussed. METHODS: Adult Wistar Albino rats were assigned into control, model (liver trauma), MSCs, and MSC-exos groups (n = 6). The study examined changes in the inflammatory environment in liver tissues were analyzed by histological examination and analysis of macrophage phenotypes. Alterations in serum metabolites were determined by untargeted metabonomics, and gut microbiota composition was characterized by 16S rDNA sequencing. Correlations between specific gut microbiota, metabolites, and inflammatory response were calculated using Spearman correlation analysis. RESULTS: Rats with liver trauma after MSCs and MSC-exos treatment exhibited attenuated inflammatory infiltration and necrosis in liver tissues. MSCs and MSC-exos treatment reduced the proportion of M1 macrophages, accompanied by a decrease in inducible nitric oxide synthase (iNOS) and tumor necrosis factor-alpha (TNF-α) levels. Furthermore, MSCs and MSC-exos treatment expanded the proportion of M2 macrophages, accompanied by an increase in arginase-1 (Arg-1) and interleukin-10 (IL-10) levels. The beneficial effects of MSC-exo treatment on rats with liver trauma were superior to those of MSC treatment. The composition and abundance of the gut microbiota and metabolites were altered in pathological rats, whereas MSC and MSC-exo intervention partially restored specific gut microbiota and metabolite alterations. At the phylum level, alterations in Bacteroidota, Proteobacteria, and Verrucomicrobiota were observed after MSC and MSC-exo intervention. At the genus level, Intestinimonas, Alistipes, Aerococcus, Faecalibaculum, and Lachnospiraceae_ND3007_group were the main differential microbiota. 6-Methylnicotinamide, N-Methylnicotinamide, Glutathione, oxidized, ISOBUTYRATE, ASCORBATE, EICOSAPENTAENOATE, GLYCEROL 3-PHOSPHATE, and Ascorbate radical were selected as important differential metabolites. There was a clear correlation between Ascorbate, Intestinimonas/Faecalibaculum and inflammatory cytokines. CONCLUSION: MSC-exos promoted the repair of tissue damage in rats with liver trauma by regulating serum metabolites and intestinal microbiota, providing new insights into how MSC-exos reduced inflammation in rats with liver trauma.


Asunto(s)
Exosomas , Microbioma Gastrointestinal , Hígado , Células Madre Mesenquimatosas , Ratas Wistar , Animales , Exosomas/metabolismo , Células Madre Mesenquimatosas/metabolismo , Hígado/metabolismo , Hígado/patología , Ratas , Masculino , Cicatrización de Heridas , Macrófagos/metabolismo , Inflamación/metabolismo
5.
Heliyon ; 10(6): e28161, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38545213

RESUMEN

Low-carbon travel assumes paramount significance in energy conservation and the establishment of an eco-friendly transportation ecosystem. This paper endeavors to explore the relationship between low-carbon travel intention, latent psychological variables, and sociodemographic attributes, drawing insights from responses of 602 residents in Hangzhou, China by structural equation model and multi-group model. In particular, we synthesize the theory of planned behavior, value-belief-norm theory, and view of incentive, a reflection of the public support for incentive policies. Results reveals that the primary determinants influencing the low-carbon travel intention encompass the view of incentive, attitude, and subjective norms. Individuals with diverse sociodemographic attributes manifest varying sensitivities, with males and elders exhibiting heightened responsiveness to incentive, while the presence of children decrease the attraction of incentive. These findings demonstrate that low-carbon travel intention can be increased by three ways, one is by the strong attraction of incentive especially tailor incentive policy, another is by making family-friendly policies to facilitate travel for groups with children, and the last is by improving the quality of low-carbon travel services thus increasing the attitude and other determinants.

6.
Chem Rev ; 124(6): 2955-3012, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38478971

RESUMEN

The structure of catalysts determines the performance of catalytic processes. Intrinsically, the electronic and geometric structures influence the interaction between active species and the surface of the catalyst, which subsequently regulates the adsorption, reaction, and desorption behaviors. In recent decades, the development of catalysts with complex structures, including bulk, interfacial, encapsulated, and atomically dispersed structures, can potentially affect the electronic and geometric structures of catalysts and lead to further control of the transport and reaction of molecules. This review describes comprehensive understandings on the influence of electronic and geometric properties and complex catalyst structures on the performance of relevant heterogeneous catalytic processes, especially for the transport and reaction over structured catalysts for the conversions of light alkanes and small molecules. The recent research progress of the electronic and geometric properties over the active sites, specifically for theoretical descriptors developed in the recent decades, is discussed at the atomic level. The designs and properties of catalysts with specific structures are summarized. The transport phenomena and reactions over structured catalysts for the conversions of light alkanes and small molecules are analyzed. At the end of this review, we present our perspectives on the challenges for the further development of structured catalysts and heterogeneous catalytic processes.

7.
World J Urol ; 42(1): 189, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38526675

RESUMEN

BACKGROUND: The stone burden based management strategy reported in the guidelines published by different associations is well known for a long time. Staghorn calculi, representing the largest burden and most complex stones, is one of the most challenging cases to practicing urologists in clinical practice. The International Alliance of Urolithiasis (IAU) has released a series of guidelines on the management of urolithiasis. PURPOSE: To develop a series of recommendations for the contemporary management management of staghorn calculi and to provide a clinical framework for urologists treating patients with these complex stones. METHODS: A comprehensive literature search for articles published in English between 01/01/1976 and 31/12/2022 in the PubMed, OVID, Embase and Medline database is performed. A series of recommendations are developed and individually graded following the review of literature and panel discussion. RESULTS: The definition, pathogenesis, pathophysiology, preoperative evaluation, intraoperative treatment strategies and procedural advice, early postoperative management, follow up and prevention of stone recurrence are summarized in the present document. CONCLUSION: A series of recommendations regarding the management of staghorn calculi, along with related commentary and supporting documentation offered in the present guideline is intended to provide a clinical framework for the practicing urologists in the management of staghorn calculi.


Asunto(s)
Cálculos Renales , Cálculos Coraliformes , Urolitiasis , Humanos , Cálculos Coraliformes/cirugía , Cálculos Renales/cirugía , Urolitiasis/terapia
8.
Int J Surg ; 110(5): 2721-2729, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38348834

RESUMEN

BACKGROUNDS: The effectiveness of procalcitonin-based algorithms in guiding antibiotic usage for febrile acute necrotizing pancreatitis (ANP) remains controversial. Metagenomic next-generation sequencing (mNGS) has been applied to diagnose infectious diseases. The authors aimed to evaluate the effectiveness of blood mNGS in guiding antibiotic stewardship for febrile ANP. MATERIALS AND METHODS: The prospective multicenter clinical trial was conducted at seven hospitals in China. Blood samples were collected during fever (T ≥38.5°C) from ANP patients. The effectiveness of blood mNGS, procalcitonin, and blood culture in diagnosing pancreatic infection was evaluated and compared. Additionally, the real-world utilization of antibiotics and the potential mNGS-guided antimicrobial strategy in febrile ANP were also analyzed. RESULTS: From May 2023 to October 2023, a total of 78 patients with febrile ANP were enrolled and 30 patients (38.5%) were confirmed infected pancreatic necrosis (IPN). Compared with procalcitonin and blood culture, mNGS showed a significantly higher sensitivity rate (86.7% vs. 56.7% vs. 26.7%, P <0.001). Moreover, mNGS outperformed procalcitonin (89.5 vs. 61.4%, P <0.01) and blood culture (89.5 vs. 69.0%, P <0.01) in terms of negative predictive value. Blood mNGS exhibited the highest accuracy (85.7%) in diagnosing IPN and sterile pancreatic necrosis, significantly superior to both procalcitonin (65.7%) and blood culture (61.4%). In the multivariate analysis, positive blood mNGS (OR=60.2, P <0.001) and lower fibrinogen level (OR=2.0, P <0.05) were identified as independent predictors associated with IPN, whereas procalcitonin was not associated with IPN, but with increased mortality (Odds ratio=11.7, P =0.006). Overall, the rate of correct use of antibiotics in the cohort was only 18.6% (13/70) and would be improved to 81.4% (57/70) if adjusted according to the mNGS results. CONCLUSION: Blood mNGS represents important progress in the early diagnosis of IPN, with particular importance in guiding antibiotic usage for patients with febrile ANP.


Asunto(s)
Antibacterianos , Fiebre , Secuenciación de Nucleótidos de Alto Rendimiento , Pancreatitis Aguda Necrotizante , Polipéptido alfa Relacionado con Calcitonina , Humanos , Pancreatitis Aguda Necrotizante/tratamiento farmacológico , Pancreatitis Aguda Necrotizante/sangre , Pancreatitis Aguda Necrotizante/diagnóstico , Polipéptido alfa Relacionado con Calcitonina/sangre , Estudios Prospectivos , Masculino , Femenino , Persona de Mediana Edad , Antibacterianos/administración & dosificación , Antibacterianos/uso terapéutico , Fiebre/tratamiento farmacológico , Fiebre/diagnóstico , Fiebre/microbiología , Adulto , China , Metagenómica , Anciano , Programas de Optimización del Uso de los Antimicrobianos , Biomarcadores/sangre
9.
J Endourol ; 38(5): 421-425, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38299514

RESUMEN

Objective: To report the initial results of an randomized clinical trail comparing the safety and efficacy between 7.5F and 9.2F flexible ureteroscope (FUS) in the management of renal calculi <2 cm. Materials and Methods: Eighty patients were enrolled and received retrograde intrarenal surgery (RIRS) with a different size FUS. The operation results and complications were compared. Results: Two cases in the 7.5F group and four cases in the 9.2F group failed to insert the 12/14F ureteral access sheath (UAS), respectively, and no significant difference (p = 0.396) was noted. However, 10/12F UAS was inserted in the 7.5F group, but not available in the 9.2F group, and thus, the 10/12F UAS inserting rate in the 7.5F group was higher than in the 9.2F group (100% vs 0%, p = 0.014), and the UAS insertion failure rate in 9.2F group was higher than in the 7.5F group (10% vs 0%, p = 0.040). The operation time in 7.5F group was shorter than the 9.2F group (35.60 ± 7.86 vs 41.05 ± 8.14, p = 0.003). Less irrigation was required in 7.5F group (813.93 ± 279.47 mL vs 1504.18 ± 385.31 mL, p = 0.000). The postoperative fever rate in 9.2F group was higher than 7.5F group (20% vs 5%, p = 0.043). There was no significant difference in sepsis (0% vs 2.5%, p = 0.314) between the two groups. No significant difference was noted in hospital stay (0.93 ± 0.49 days vs 1.14 ± 0.64 days, p = 0.099) between the two groups. The final stone-free rate (SFR) in 7.5F group was higher than 9.2F group (95% vs 80%, p = 0.043). Conclusion: The latest 7.5F mini FUS was a reliable instrument in RIRS to keep a good visualization with low requirement of irrigation, low postoperative infection complication, and also a high SFR when compared with the conventional 9.2F FUS. Clinical Trial Registration: NCT05231577.


Asunto(s)
Cálculos Renales , Ureteroscopios , Humanos , Masculino , Femenino , Persona de Mediana Edad , Cálculos Renales/cirugía , Adulto , Riñón/cirugía , Resultado del Tratamiento , Complicaciones Posoperatorias/etiología , Docilidad , Anciano
10.
Mater Today Bio ; 25: 100956, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38322657

RESUMEN

The rational design of multifunctional biomaterials with hierarchical porous structure and on-demand biological activity is of great consequence for bone tissue engineering (BTE) in the contemporary world. The advanced combination of trace element cerium ions (Ce3+) with bone repair materials makes the composite material capable of promoting angiogenesis and enhancing osteoblast activity. Herein, a living and phosphorylated injectable porous hydrogel microsphere (P-GelMA-Ce@BMSCs) is constructed by microfluidic technology and coordination reaction with metal ion ligands while loaded with exogenous BMSCs. Exogenous stem cells can adhere to and proliferate on hydrogel microspheres, thus promoting cell-extracellular matrix (ECM) and cell-cell interactions. The active ingredient Ce3+ promotes the proliferation, osteogenic differentiation of rat BMSCs, and angiogenesis of endotheliocytes by promoting mineral deposition, osteogenic gene expression, and VEGF secretion. The enhancement of osteogenesis and improvement of angiogenesis of the P-GelMA-Ce scaffold is mainly associated with the activation of the Wnt/ß-catenin pathway. This study could provide novel and meaningful insights for treating bone defects with biofunctional materials on the basis of metal ions.

11.
Int J Biol Macromol ; 263(Pt 2): 130379, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38403214

RESUMEN

Cytoplasmic coat protein complex II (COPII) plays a multifunctional role in the transport of newly synthesized proteins, autophagosome formation, and endoplasmic reticulum (ER)-ER-phagy. However, the molecular mechanisms of the COPII subunit in ER-phagy in plant pathogens remain unknown. Here, we identified the subunit of COPII vesicles (BcSfb3) and explored the importance of BcSfb3 in Botrytis cinerea. BcSfb3 deletion affected vegetative growth, conidiation, conidial morphology, and plasma membrane integrity. We confirmed that the increase in infectious hyphal growth was delayed in the ΔBcSfb3 mutant, reducing its pathogenicity in the host plant. Furthermore, the ΔBcSfb3 mutant was sensitive to ER stress, which caused massive ER expansion and induced the formation of ER whorls that were taken up into the vacuole. Further examination demonstrated that BcSfb3 deletion caused ER stress initiated by unfolded protein response, and which led to the promotion of ER-phagy and autophagy that participate in sclerotia formation. In conclusion, these results demonstrate that BcSfb3 plays an important role in fungal development, pathogenesis, ER-phagy and autophagy in B. cinerea.


Asunto(s)
Autofagia , Retículo Endoplásmico , Virulencia , Retículo Endoplásmico/metabolismo , Estrés del Retículo Endoplásmico , Botrytis
12.
Chem Sci ; 15(3): 1046-1050, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38239696

RESUMEN

The strong promotion effects of alkali/alkaline earth metals are frequently reported for heterogeneous catalytic processes such as propane dehydrogenation (PDH), but their functioning principles remain elusive. This paper describes the effect of the addition of calcium (Ca) on reducing the deactivation rate of platinum-tin (Pt-Sn) catalyzed PDH from 0.04 h-1 to 0.0098 h-1 at 873 K under a WHSV of 16.5 h-1 of propane. The Pt-Sn-Ca catalyst shows a high propylene selectivity of >96% with a propylene production rate of 41 molC3H6 (gPt h)-1 and ∼1% activity loss after regeneration. The combination of characterization and DFT simulations reveals that Ca acts as a structural promoter favoring the transition of Snn+ in the parent catalyst to Sn0 during reduction, and the latter is an electron donor that increases the electron density of Pt. This greatly suppresses coke formation from deep dehydrogenation. Moreover, it was found that Ca promotes the formation of a highly reactive and sintering-resistant sub-nano Pt-Sn alloy with a diameter of approximately 0.8 nm. These lead to high activity and selectivity for the Pt-Sn-Ca catalyst for PDH.

13.
Nat Chem ; 16(4): 575-583, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38168925

RESUMEN

In heterogeneous catalysis, the catalytic dehydrogenation reactions of hydrocarbons often exhibit a negative pressure dependence on hydrogen due to the competitive chemisorption of hydrocarbons and hydrogen. However, some catalysts show a positive pressure dependence for propane dehydrogenation, an important reaction for propylene production. Here we show that the positive activity dependence on H2 partial pressure of gallium oxide-based catalysts arises from metastable hydride mediation. Through in situ spectroscopic, kinetic and computational analyses, we demonstrate that under reaction conditions with H2 co-feeding, the dissociative adsorption of H2 on a partially reduced gallium oxide surface produces H atoms chemically bonded to coordinatively unsaturated Ga atoms. These metastable gallium hydride species promote C-H bond activation while inhibiting deep dehydrogenation. We found that the surface coverage of gallium hydride determines the catalytic performance. Accordingly, benefiting from proper H2 co-feeding, the alumina-supported, trace additive-modified gallium oxide catalyst GaOx-Ir-K/Al2O3 exhibited high activity and selectivity at high propane concentrations.

14.
Adv Healthc Mater ; 13(3): e2302153, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37922941

RESUMEN

The periosteum plays a vital role in the regeneration of critical-size bone defects and highly comminuted fractures, promoting the differentiation of osteoblasts, accelerating the reconstruction of the vascular network, and guiding bone tissue regeneration. However, the materials loaded with exogenous growth factors are limited by the release and activity of the elements. Therefore, the material structure must be carefully designed for the periosteal function. Here, a self-adaptive biomimetic periosteum strategy is proposed, which is a novel interpenetrating double network hydrogel consisting of diselenide-containing gelatin and calcium alginate (modified natural collagen and polysaccharide) to enhance the stability, anti-swelling, and delayed degradation of the hydrogel. The diselenide bond continuously releases nitric oxide (NO) by metabolizing endogenous nitrosated thiols (RSNO), activates the nitric oxide-cycle guanosine monophosphate (NO-cGMP) signal pathway, coordinates the coupling effect of angiogenesis and osteogenesis, and accelerates the repair of bone defects. This self-adaptive biomimetic periosteum with the interpenetrating double network structure formed by the diselenide-containing gelatin and calcium alginate has been proven to be safe and effective in repairing critical-size bone defects and is expected to provide a promising strategy for solving clinical problems.


Asunto(s)
Óxido Nítrico , Periostio , Periostio/química , Óxido Nítrico/análisis , Gelatina/farmacología , Gelatina/química , Biomimética , Angiogénesis , Regeneración Ósea , Osteogénesis , Alginatos , Hidrogeles/química , Andamios del Tejido/química , Ingeniería de Tejidos
15.
Clin Kidney J ; 16(11): 2205-2215, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37915892

RESUMEN

Background: Genetic variations are linked to kidney stone formation. However, the association of single nucleotide polymorphism (SNPs) and stone recurrence has not been well studied. This study aims to identify genetic variants associated with kidney stone recurrences and to construct a predictive nomogram model using SNPs and clinical features to predict the recurrence risk of kidney stones. Methods: We genotyped 49 SNPs in 1001 patients who received surgical stone removal between Jan 1 and Dec 31 of 2012. All patients were confirmed stone-free by CT scan and then received follow-up at least 5 years. SNP associations with stone recurrence were analyzed by Cox proportion hazard model. A predictive nomogram model using SNPs and clinical features to predict the recurrence risk of kidney stones was developed by use of LASSO Cox regression. Results: The recurrence rate at 3, 5, 7 years were 46.8%, 71.2%, and 78.4%, respectively. 5 SNPs were identified that had association with kidney stone recurrence risk. We used computer-generated random numbers to assign 500 of these patients to the training cohort and 501 patients to the validation cohort. A nomogram that combined the 14-SNPs-based classifier with the clinical risk factors was constructed. The areas under the curve (AUCs) at 3, 5 and 7 years of this nomogram was 0.645, 0.723, and 0.75 in training cohort, and was 0.631, 0.708, and 0.727 in validation cohort, respectively. Results show that the nomogram presented a higher predictive accuracy than those of the SNP classifier or clinical factors alone. Conclusion: SNPs are significantly associated with kidney stone recurrence and should add prognostic value to the traditional clinical risk factors used to assess the kidney stone recurrence. A nomogram using clinical and genetic variables to predict kidney stone recurrence has revealed its potential in the future as an assessment tool during the follow-up of kidney stone patients.

16.
BMC Cancer ; 23(1): 1044, 2023 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-37904102

RESUMEN

BACKGROUND: Pancreatic cancer is a highly lethal disease with no effective treatments. Lactobacillus casei (L. casei) and Lactobacillus reuteri (L. reuteri) exhibited therapeutic effects on several cancers, but their roles in pancreatic cancer are unknown. This study aims to explore how L. casei & L. reuteri influence pancreatic cancer and the underlying mechanisms. METHODS: Pancreatic cancer cells were treated with L. casei & L. reuteri and co-cultured with macrophages in a transwell system in vitro. Pancreatic cancer xenograft model was established and L. casei & L. reuteri was used to treat mice in vivo. MTT, CCK-8 assay or immunohistochemical staining were used to determine the proliferation of pancreatic cancer cells or tumor tissues. Transwell assay was applied to test the migration and invasion of pancreatic cells. RT-qPCR was utilized to assess TLR4 and MyD88 expressions in pancreatic cells or tumor tissues. WB, immunofluorescence staining, or flow cytometry was used to evaluate the M1/M2 polarization of macrophages. Besides, the composition of gut microbiota of tumor-bearing mice was determined by 16 S rRNA sequencing, and ultra-high performance liquid chromatography-mass spectrometry (UPLC-MS) untargeted metabolomics was used to evaluate the metabolic profiles of feces. RESULTS: L. casei & L. reuteri inhibited the proliferation, migration, invasion of pancreatic cancer cells and pancreatic cancer cell-induced M2 polarization of macrophages by suppressing TLR4. Meanwhile, L. casei & L. reuteri repressed pancreatic cancer growth and promoted M1 macrophage polarization. Besides, L. casei & L. reuteri reduced fecal Alloprevotella and increased fecal azelate and glutamate in nude mice, while TLR4 inhibitor TAK-242 increased Clostridia UCG-014, azelate, uridine, methionine sulfoxide, oxypurinol, and decreased glyceryl monoester in the feces of pancreatic tumor-bearing mice. Fecal oxypurinol and glyceryl monoester levels were positively or negatively associated with gut Clostridia UCG-014 abundance, respectively. CONCLUSION: L. casei & L. reuteri alleviate pancreatic cancer by inhibiting TLR4 to promote macrophage M1 polarization and regulate gut microbial homeostasis.


Asunto(s)
Microbioma Gastrointestinal , Lacticaseibacillus casei , Limosilactobacillus reuteri , Neoplasias Pancreáticas , Ratones , Humanos , Animales , Receptor Toll-Like 4/metabolismo , Ratones Desnudos , Cromatografía Liquida , Oxipurinol/metabolismo , Oxipurinol/farmacología , Espectrometría de Masas en Tándem , Macrófagos/metabolismo , Neoplasias Pancreáticas/terapia , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas
17.
Maturitas ; 178: 107848, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37757613

RESUMEN

OBJECTIVES: To assess the associations of both the level of circulating vitamin D and the ratio of omega-3 fatty acids to total fatty acids (omega-3 %) with mortality among participants with rheumatoid arthritis. STUDY DESIGN: This study included 4,293 and 1,157 adults with rheumatoid arthritis identified by self-report from the UK Biobank for the analysis of vitamin D and omega-3 %, respectively. MAIN OUTCOME MEASURES: Death outcomes were obtained from the National Health Service Information Centre (England and Wales) and the National Health Service Central Register Scotland (Scotland). Cox proportional hazards models were used to estimate hazard ratios and 95 % confidence intervals for mortality. RESULTS: The medians (25th-75th percentiles) of serum 25(OH)D and omega-3 % were 45.8 (31.4-62.9) nmol/L and 4.1 % (3.3 %-5.1 %), respectively. During 52,612 person-years of follow-up in the 25(OH)D group, 502 all-cause deaths occurred; and during 14,192 person-years of follow-up in the omega-3 % group, 122 all-cause deaths occurred. Rheumatoid arthritis patients with vitamin D levels of at least 20 nmol/L had an approximately 40-50 % lower risk of all-cause mortality than those with severe vitamin D deficiency (hazard ratio ranging from 0.51 to 0.62, all P values < 0.05). Each unit increase in natural log-transformed 25(OH)D was associated with a 22 % reduction in the risk of all-cause mortality, and a U-shaped association between serum 25(OH)D and all-cause mortality was found. However, the association between omega-3 % and mortality was not significant. CONCLUSIONS: Lower serum 25(OH)D concentration, but not omega-3 %, was significantly associated with higher all-cause mortality in patients with rheumatoid arthritis. Optimizing serum vitamin D levels may be an important factor in reducing mortality risk in this population.


Asunto(s)
Artritis Reumatoide , Ácidos Grasos Omega-3 , Deficiencia de Vitamina D , Humanos , Vitamina D , Estudios de Cohortes , Medicina Estatal , Vitaminas , Deficiencia de Vitamina D/complicaciones
18.
Regen Biomater ; 10: rbad074, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37719927

RESUMEN

Treating articular cartilage defects in patients remains a challenging task due to the absence of blood vessels within the cartilage tissue. The regenerative potential is further compromised by an imbalance between anabolism and catabolism, induced by elevated levels of reactive oxygen species. However, the advent of tissue engineering introduces a promising strategy for cartilage regeneration, offering viable solutions such as mechanical support and controlled release of chondrogenic molecules or cytokines. In this study, we developed an antioxidant scaffold by incorporating natural silk fibroin (SF) and kartogenin (KGN)-loaded liposomes (SF-Lipo@KGN). The scaffold demonstrated appropriate pore size, connectivity, and water absorption and the sustained release of KGN was achieved through the encapsulation of liposomes. In vitro experiments revealed that the SF-Lipo@KGN scaffolds exhibited excellent biocompatibility, as evidenced by enhanced cell adhesion, migration, and proliferation of chondrocytes. The SF-Lipo@KGN scaffolds were found to stimulate cartilage matrix synthesis through the activation of the nuclear factor erythroid-2-related factor 2/heme oxygenase-1 antioxidant signaling pathway. In vivo experiments demonstrated the effective promotion of articular cartilage regeneration by the SF-Lipo@KGN scaffolds, which enhanced extracellular matrix anabolism and restored the intrinsic redox homeostasis. Overall, this study successfully developed biomimetic KGN-loaded scaffolds that restore cartilage redox homeostasis, indicating promising prospects for cartilage tissue engineering.

19.
Chem Sci ; 14(33): 8777-8784, 2023 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-37621421

RESUMEN

The complex reconstructed structure of materials can be revealed by global optimization. This paper describes a hybrid evolutionary algorithm (HEA) that combines differential evolution and genetic algorithms with a multi-tribe framework. An on-the-fly machine learning calculator is adopted to expedite the identification of low-lying structures. With a superior performance to other well-established methods, we further demonstrate its efficacy by optimizing the complex oxidized surface of Pt/Pd/Cu with different facets under (4 × 4) periodicity. The obtained structures are consistent with experimental results and are energetically lower than the previously presented model.

20.
Proc Natl Acad Sci U S A ; 120(34): e2305604120, 2023 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-37585465

RESUMEN

Electrochemical conversion of N2 into ammonia presents a sustainable pathway to produce hydrogen storage carrier but yet requires further advancement in electrocatalyst design and electrolyzer integration. This technology suffers from low selectivity and yield owing to the extremely strong N≡N bond and the exceptionally low solubility of N2 in aqueous systems. A high NH3 synthesis performance is restricted by the high activation energy of N≡N bond and the supply insufficiency of N2 to active sites. This paper describes the introduction of electron-rich Bi0 sites into Ag catalysts with a high-pressure electrolyzer that enables a dramatically enhanced Faradaic efficiency of 44.0% and yield of 28.43 µg cm-2 h-1 at 4.0 MPa. Combined with density functional theory results, in situ attenuated total reflectance surface-enhanced infrared absorption spectroscopy demonstrates that N2 reduction reaction follows an associative mechanism, in which a high coverage of N-N bond and -NH2 intermediates suggest electron-rich Bi0 boosts sound activation of N2 molecules and low hydrogenation barrier. The proposed strategy of engineering electrochemical catalysts and devices provides powerful guidelines for achieving industrial-level green ammonia production.

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