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1.
Sci Total Environ ; 946: 174437, 2024 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-38960199

RESUMEN

Fossil fuels, especially coal, have played a pivotal role in driving technological and economic advancements over the past century, though accompanied by numerous environmental challenges. Rapid progress in green and sustainable energy sources, including tidal, wind, and solar energy, coupled with growing environmental concerns, the conventional coal industry is experiencing a sustained decline in both size and financial viability. This situation necessitates the urgent adoption of advanced approaches to coal utilization. Beyond serving as an energy source, coal and its by-products, known as coal waste, can serve as valuable resources for the development of advanced materials, including photocatalysts. The advancement of photocatalytic materials derived from coal and coal waste can capitalize on these natural carbon and mineral sources, providing a viable solution to numerous environmental challenges. Currently, research in this domain remains in its early stages, with existing studies primarily focusing on specific types of photocatalysts or particular aspects of the fabrication process. Therefore, available coal-based and coal waste-based photocatalytic materials were systematically examined and categorized into six types according to their composition and dimensional/structural characteristics. Each type of photocatalytic material was introduced, along with common fabrication and characterization technologies. Representative works were discussed in detail to highlight the unique features of different types of coal-based and coal waste-based photocatalytic materials. Furthermore, the promising applications of these materials in environmental protection and pollution treatment were summarized, while also addressing the challenges and prospects in this research field. This review comprehensively overviews the fundamental knowledge and recent advancements in photocatalytic materials derived from coal and coal waste, with the goal of catalyzing the development of next generation photocatalysts and contributing to the transformation of the conventional coal industry.

2.
Materials (Basel) ; 17(10)2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38793443

RESUMEN

In light of the pressing environmental and health issues stemming from electromagnetic pollution, advanced electromagnetic wave absorbing materials are urgently sought to solve these problems. The present study delved into the fabrication of the resorcinol formaldehyde (RF)/SiO2 ceramic particles using the sol-gel route. From SEM images and XRD and XPS analysis, it can be seen that the RF/SiO2 ceramic particles are successfully generated after heat treatment at 1500 °C. At room temperature, the sample treated at 1500 °C exhibited a minimum reflection loss of -47.6 dB in the range of 2-18 GHz when the matching thickness was 5.5 mm, showcasing strong attenuation capabilities. Moreover, these particles demonstrated a considerable effective electromagnetic wave absorption bandwidth of 3.14 GHz, evidencing their potential for wideband electromagnetic wave absorption. The temperature adjustment played a pivotal role in achieving optimal impedance matching. When the heat treatment temperature is increased from 800 °C to 1500 °C, the dielectric properties of the material are improved, thus achieving the best impedance matching, thereby optimizing the material's absorption properties for specific frequency ranges, which makes it possible to customize the electromagnetic wave-absorbing characteristics to meet specific requirements across a range of applications.

3.
J Int Soc Sports Nutr ; 21(1): 2352393, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38775452

RESUMEN

BACKGROUND: Sarcopenia and knee osteoarthritis are common age-related diseases that have become important public health issues worldwide. Few studies have reported the association between muscle mass loss and knee osteoarthritis. This may be due to the high level of heterogeneity between studies stemming from different definitions of muscle mass loss. METHODS: The systematic searches were carried out in PubMed and Web of Science from the inception of the databases until 13 January 2023, by two independent researchers. Pooled odds ratios (ORs) for overall and subgroup analyses were obtained using either a random effects model (I2 >50%) or fixed effects model (I2 ≤50%) in Stata. RESULTS: Of the 1,606 studies identified, we ultimately included 12 articles on the association between muscle mass and knee osteoarthritis (prospective: n = 5; cross-sectional: n = 7). Low-quality evidence indicated that low muscle mass index and sarcopenic obesity increase the odds of knee osteoarthritis (low muscle mass index OR: 1.36, 95% CI: 1.13-1.64; sarcopenic obesity OR: 1.78, 95% CI: 1.35-2.34). However, no association was observed between general sarcopenia or low muscle mass with knee osteoarthritis. CONCLUSION: This systematic review and meta-analysis revealed that low muscle mass index and sarcopenic obesity were associated with an increased risk of developing knee osteoarthritis.


Asunto(s)
Obesidad , Osteoartritis de la Rodilla , Sarcopenia , Osteoartritis de la Rodilla/complicaciones , Sarcopenia/complicaciones , Humanos , Obesidad/complicaciones , Músculo Esquelético
4.
Int J Surg ; 110(6): 3307-3325, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38573134

RESUMEN

BACKGROUND: Sleeve gastrectomy (SG) is known to alleviate non-alcoholic fatty liver disease (NAFLD) and restore liver function; however, its underlying mechanism remains unclear. MATERIALS AND METHODS: We investigated the effect of SG on the metabolic phenotype of diet-induced obese (DIO) mice. Postoperative stained liver images were analyzed to determine the hepatocyte proliferation phenotype. Single-cell RNA sequencing was used to characterize the regeneration signals of the liver after SG in DIO mice, and real-time quantitative reverse transcription PCR was performed to verify the above results. We employed Olink proteomics to capture serum element changes and investigated the role of Yes1 protein in liver regeneration and carcinogenesis through the Hippo-YAP pathway. DIO mice were treated with YAP inhibitor verteporfin after SG mice to clarify whether SG-induced liver regeneration is related to the YAP signaling pathway. RESULTS: SG significantly reduced NAFLD-associated dysfunction in hepatocytes and replaced them with fully functional hepatocytes, which have a high regenerative capacity across the entire liver. SG also enhanced the hepatic regenerative capacity, as demonstrated by SG combined with hepatic lobectomy in healthy mice. Yes1 protein was identified as the signaling molecule most closely related to classical regeneration signals. Our study showed that SG-enhanced proliferation and improved metabolism did not depend on YAP signaling. CONCLUSION: SG can enhance hepatic regenerative capacity and improve liver metabolism. This study provides a better understanding of the mechanisms underlying SG-induced metabolic improvements.


Asunto(s)
Modelos Animales de Enfermedad , Gastrectomía , Hepatocitos , Regeneración Hepática , Enfermedad del Hígado Graso no Alcohólico , Animales , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/cirugía , Regeneración Hepática/fisiología , Ratones , Hepatocitos/metabolismo , Gastrectomía/métodos , Masculino , Ratones Endogámicos C57BL , Proliferación Celular , Transducción de Señal
5.
Polymers (Basel) ; 16(8)2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38675049

RESUMEN

The preparation of an environmentally friendly and efficient flocculant for solid-liquid separation in industrial wastewater is highly important. In this study, a novel cationic flocculant (AL-g-PAMA) was synthesized by a thermal initiation method using alkali lignin (AL) as the main chain and acrylamide (AM) and methacrylamido propyl trimethyl ammonium chloride (MAPTAC) as the grafted side chains. The structure, thermal stability, and surface morphology of the copolymers were investigated by various characterization methods. The results indicated the successful synthesis of AL-g-PAMA. AL-g-PAMA was applied to improve solid-liquid separation in kaolin suspensions. The results showed that AL-g-PAMA had excellent flocculation-sedimentation and dewatering efficiency. When the dosage of AL-g-PAMA #5 was 600.0 g/t(s), the thickness of the compressed layer was 2.2 cm, the floc settling velocity was 24.1 cm/min, and the transmittance of the supernatant was 84.0%. The moisture content of the filter cake decreased from 55.0% to 43.4% after treatment with AL-g-PAMA #5. The results of zeta potential and focused beam reflectance measurement (FBRM) analysis indicated that bridging and electroneutralization were the main flocculation mechanisms. Therefore, this study extends the potential for using lignin as a bioflocculant and provides a feasible approach to efficiently purify high-turbidity wastewater.

6.
Sci Rep ; 14(1): 6655, 2024 03 20.
Artículo en Inglés | MEDLINE | ID: mdl-38509147

RESUMEN

Tripartite motif-containing protein 7 (TRIM7), as an E3 ligase, plays an important regulatory role in various physiological and pathological processes. However, the role of TRIM7 in gastric cancer (GC) is still undefined. Our study detected the expression of TRIM7 in clinical specimens and investigated the regulatory effect and molecular mechanism of TRIM7 on GC progression through in vitro and in vivo experiments. Our finding showed that TRIM7 was significantly downregulated in GC, and patients with high expression of TRIM7 showed long overall survival. Both in vitro and in vivo experiments showed that TRIM7 dramatically suppressed the malignant progression of GC. Further investigation showed that ferroptosis was the major death type mediated by TRIM7. Mechanistically, TRIM7 interacted with SLC7A11 through its B30.2/SPRY domain and promoted Lys48-linked polyubiquitination of SLC7A11, which effectively suppressing SLC7A11/GPX4 axis and inducing ferroptosis in GC cells. In vivo experiments and correlation analysis based on clinical specimens further confirmed that TRIM7 inhibited tumor growth through suppressing SLC7A11/GPX4 axis. In conclusion, our investigation demonstrated for the first time that TRIM7, as a tumor suppressor, induced ferroptosis via targeting SLC7A11 in GC, which provided a new strategy for the molecular therapy of GC by upregulating TRIM7.


Asunto(s)
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/genética , Ubiquitina-Proteína Ligasas/genética , Transformación Celular Neoplásica , Carcinogénesis , Ubiquitinación , Sistema de Transporte de Aminoácidos y+/genética , Proteínas de Motivos Tripartitos/genética
7.
iScience ; 27(2): 108843, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38303702

RESUMEN

This study was designed to explore the roles of CREB3L4 in the pathogenesis and drug resistance of hepatocellular carcinoma (HCC). The proliferation of HCC lines was determined in the presence of CREB3L4 over-expression and silencing. Chromatin immunoprecipitation (ChIP) assay and dual-luciferase reporter assay were performed to screen the potential target of CREB3L4 on mTORC1. Xenografted tumor model was established to define the regulatory effects of CREB3L4 in the tumorigenesis. Then we evaluated the roles of CREB3L4 in chemosensitivity to sorafenib treatment. CREB3L4 significantly induced the HCC cell proliferation by modulating the activation of mTROC1-S6K1 signaling pathway via binding with RHEB promoter. Moreover, CREB3L4 dramatically inhibited the chemosensitivity to sorafenib treatment via up-regulating RHEB-mTORC1 signaling. CREB3L4 promoted HCC progression and decreased its chemosensitivity to sorafenib through up-regulating RHEB-mTORC1 signaling pathway, indicating a potential treatment strategy for HCC through targeting CREB3L4.

8.
Sci Adv ; 10(8): eadk7140, 2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38394197

RESUMEN

Acaryochloris marina is a unique cyanobacterium using chlorophyll d (Chl d) as its major pigment and thus can use far-red light for photosynthesis. Photosystem II (PSII) of A. marina associates with a number of prochlorophyte Chl-binding (Pcb) proteins to act as the light-harvesting system. We report here the cryo-electron microscopic structure of a PSII-Pcb megacomplex from A. marina at a 3.6-angstrom overall resolution and a 3.3-angstrom local resolution. The megacomplex is organized as a tetramer consisting of two PSII core dimers flanked by sixteen symmetrically related Pcb proteins, with a total molecular weight of 1.9 megadaltons. The structure reveals the detailed organization of PSII core consisting of 15 known protein subunits and an unknown subunit, the assembly of 4 Pcb antennas within each PSII monomer, and possible pathways of energy transfer within the megacomplex, providing deep insights into energy transfer and dissipation mechanisms within the PSII-Pcb megacomplex involved in far-red light utilization.


Asunto(s)
Complejo de Proteína del Fotosistema II , Proclorofitas , Complejo de Proteína del Fotosistema II/metabolismo , Clorofila/metabolismo , Fotosíntesis
9.
Adv Healthc Mater ; 13(12): e2303297, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38315874

RESUMEN

Skin injury is a common health problem worldwide, and the highly complex healing process poses critical challenges for its management. Therefore, wound dressings with salutary effects are urgently needed for wound care. However, traditional wound dressing with a single function often fails to meet the needs of wound repair, and the integration of multiple functions has been required for wound repair. Herein, Cu2+-chelated epigallocatechin gallate nanoparticles (EAC NPs), with radical scavenging, inflammation relieving, bacteria restraining, and vascularization accelerating capacities, are adopted to functionalize collagen scaffold, aiming to promote wound healing. Radical scavenging experiments verify that EAC NPs could efficiently scavenge radicals. Additionally, EAC NPs could effectively remove Escherichia coli and Staphylococcus aureus. H2O2 stimuli-responsive EAC NPs show slow and sustained release properties of Cu2+. Furthermore, EAC NPs exhibit protective effects against H2O2-induced oxidative-stress damage and anti-inflammatory activity in vivo. Physicochemical characterizations show that the introduction of EAC NPs does not disrupt the gelation behavior of collagen, and the composite scaffolds (CS) remain porous structure similar to collagen scaffold. Animal experiments demonstrate that CS could promote wound healing through improving the thickness of renascent epidermis and number of new vessels. CS with multiple salutary functions is a promising dressing for wound care.


Asunto(s)
Antibacterianos , Antiinflamatorios , Catequina , Catequina/análogos & derivados , Colágeno , Cobre , Nanopartículas , Cicatrización de Heridas , Catequina/química , Catequina/farmacología , Cicatrización de Heridas/efectos de los fármacos , Cobre/química , Cobre/farmacología , Animales , Antibacterianos/química , Antibacterianos/farmacología , Colágeno/química , Nanopartículas/química , Antiinflamatorios/química , Antiinflamatorios/farmacología , Ratones , Antioxidantes/farmacología , Antioxidantes/química , Staphylococcus aureus/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Andamios del Tejido/química , Masculino , Neovascularización Fisiológica/efectos de los fármacos
10.
Langmuir ; 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38324784

RESUMEN

Rational design and fabrication of metal-organic framework-derived metal oxide (MO) materials featuring a hollow structure and active support can significantly enhance their catalytic activity for specific reactions. Herein, a series of Co3O4 nanoparticles (NPs) immobilized in boron nitride (denoted as Co3O4@BN) with highly open and precisely controllable structures were constructed by an in situ self-assembly method combined with a controlled annealing process. The obtained Co3O4@BN not only possesses a hollow structure but also shows highly dispersed Co3O4 NPs and high loadings of up to 34.3 wt %. Owing to the ultrafine particle size and high dispersity, the optimized Co3O4@BN exhibits high catalytic activity for the cycloaddition of CO2 to epoxides under mild conditions (i.e., 100 °C and CO2 balloon), resulting in at least 4.5 times higher yields (99%) of styrene carbonate than that of Co3O4 synthesized by the pristine ZIF-67. This strategy sheds light on the rational design of hollow MO materials for various advanced applications.

11.
J Environ Manage ; 354: 120342, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38382431

RESUMEN

In this work, ultraviolet irradiation was employed to assist in the preparation of a novel photocatalyst composite in the form of carbon dots/zeolite-4A/TiO2, using coal tailings as the source of silicon-aluminum and carbon. The composite was designed for the degradation of methylene blue under 500 W of UV light irradiation. Zeolite-4A was used as a support for the well-dispersed carbon dots and TiO2 nanoparticles. The as-prepared composites were subjected to thorough characterization, confirming the successful formation of zeolite-4A with a cube structure, along with the loading of TiO2 and coal-based CDs in the composites. The experimental results demonstrated that the UV-CZTs nanocomposites exhibited a remarkable removal efficiency of 90.63% within 90 min for MB. The corresponding rate constant was exceptionally high at 0.0331 min-1, surpassing that of the Dark-CZTs and pure TiO2. This significant enhancement was possibly due to the synergistic effect of adsorption photocatalysis of the UV-CZTs, combined with the excellent electron-accepting capabilities of the coal-based CDs, which led to highly improved charge separation. An investigation of the spent photocatalyst's recyclability revealed that it retained a remarkable 82.94% MB removal efficiency after five consecutive cycles, signifying the stability of the composite. Trapping experiments also elucidated the primary reactive species responsible for MB degradation, which were identified as photo-generated holes and ⸱O2- species. By this process, the hydroxyl radicals generated in the system successfully promoted the transformation of coal tailings to coal-based zeolite and coal-based CDs. Coal-based zeolite served as an excellent carrier of titanium dioxide, which improved its dispersibility. The inhibition of e--h+ recombination of titanium dioxide by introducing coal-based CDs improved the photocatalytic ability of titanium dioxide. Through this study, coal tailings, as a coal processing waste, were transformed into high-value materials, and relevant photocatalytic composite materials could be prepared with broad application prospects.


Asunto(s)
Rayos Ultravioleta , Zeolitas , Colorantes , Zeolitas/química , Titanio/química , Carbón Mineral , Carbono , Catálisis
12.
Hepatol Commun ; 8(1)2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38206197

RESUMEN

BACKGROUND: Primary sclerosing cholangitis (PSC) is an immune-mediated, chronic cholestatic liver disease. Currently, liver transplantation is the only established life-saving treatment. Several studies have evaluated the effect of different biologic therapies on PSC with inconclusive findings. We conducted a systematic review and meta-analysis to assess the effects of biologics in PSC and associated inflammatory bowel disease (IBD). METHODS: MEDLINE, Scopus, and Embase were searched up to July 31, 2023, for studies reporting the effects of biologics in patients with PSC-IBD. Effects of biologic therapy on alkaline phosphatase, total bilirubin, ulcerative colitis response score, and adverse events were calculated and expressed as standardized difference of means (SMD), proportions, and 95% CI using a random-effects model. RESULTS: Six studies, including 411 PSC-IBD patients who received biologics, were included. Biologic treatment was associated with no change in alkaline phosphatase (SMD: 0.1, 95% CI: -0.07 -0.17, p=0.43), but a small and statistically significant increase in total bilirubin (SMD: 0.2, 95% CI: 0.05-0.35, p<0.01). 31.2% (95% CI: 23.8-39.7) of patients with IBD achieved endoscopic response, and there was a significant improvement in ulcerative colitis response score (SMD: -0.6,95% CI: -0.88 to 0.36, p<0.01). Furthermore, 17.6% (95% CI: 13.0-23.5) of patients experienced adverse events severe enough to discontinue therapy, and 29.9% (95% CI: 25.2-34.8) had a loss of response to biologics. CONCLUSIONS: Treatment of patients with PSC-IBD with biologics (vedolizumab, infliximab, and adalimumab) was not associated with improvement of biochemical markers of cholestasis. Biologics are effective in treating the colitis associated with PSC. Vedolizumab was associated with worsening liver enzymes in contrast to other biologics, a finding that warrants further study.


Asunto(s)
Productos Biológicos , Colangitis Esclerosante , Colestasis , Colitis Ulcerosa , Enfermedades Inflamatorias del Intestino , Humanos , Colitis Ulcerosa/tratamiento farmacológico , Fosfatasa Alcalina , Colangitis Esclerosante/complicaciones , Colangitis Esclerosante/tratamiento farmacológico , Enfermedades Inflamatorias del Intestino/complicaciones , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Bilirrubina , Productos Biológicos/efectos adversos
13.
Nat Commun ; 15(1): 842, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38287016

RESUMEN

The constant emergence of SARS-CoV-2 variants continues to impair the efficacy of existing neutralizing antibodies, especially XBB.1.5 and EG.5, which showed exceptional immune evasion properties. Here, we identify a highly conserved neutralizing epitope targeted by a broad-spectrum neutralizing antibody BA7535, which demonstrates high neutralization potency against not only previous variants, such as Alpha, Beta, Gamma, Delta and Omicron BA.1-BA.5, but also more recently emerged Omicron subvariants, including BF.7, CH.1.1, XBB.1, XBB.1.5, XBB.1.9.1, EG.5. Structural analysis of the Omicron Spike trimer with BA7535-Fab using cryo-EM indicates that BA7535 recognizes a highly conserved cryptic receptor-binding domain (RBD) epitope, avoiding most of the mutational hot spots in RBD. Furthermore, structural simulation based on the interaction of BA7535-Fab/RBD complexes dissects the broadly neutralizing effect of BA7535 against latest variants. Therapeutic and prophylactic treatment with BA7535 alone or in combination with BA7208 protected female mice from the circulating Omicron BA.5 and XBB.1 variant infection, suggesting the highly conserved neutralizing epitope serves as a potential target for developing highly potent therapeutic antibodies and vaccines.


Asunto(s)
COVID-19 , Femenino , Animales , Humanos , Ratones , SARS-CoV-2/genética , Anticuerpos Neutralizantes , Anticuerpos ampliamente neutralizantes , Epítopos/genética , Anticuerpos Antivirales , Glicoproteína de la Espiga del Coronavirus/genética
14.
Eur J Med Res ; 29(1): 47, 2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-38212810

RESUMEN

BACKGROUND: This study was designed to clarify the function and potential mechanism of gentiopicroside (GPS) in regulating the malignant progression of gastric cancer (GC) through in vitro cellular experiments and in vivo animal models. METHODS: AGS and HGC27 cells were divided into control group and GPS treatment groups (50 µM and 100 µM). Then, the cellular proliferation, colony formation, migration, invasion, and apoptosis were detected, respectively. Transmission electron microscope (TEM) was used to observe the mitochondrial changes, and the mitochondrial membrane potential (MMP) was determined using the JC-1 commercial kit. Network pharmacology analysis was utilized to screen the potential molecule that may be related to the GPS activity on GC cells, followed by validation tests using Western blot in the presence of specific activator. In addition, xenografted tumor model was established using BALB/c nude mice via subcutaneous injection of HGC27 cells, along with pulmonary metastasis model. Then, the potential effects of GPS on the tumor growth and metastasis were detected by immunohistochemistry (IHC) and HE staining. RESULTS: GPS inhibited the proliferation, invasion and migration of GC cell lines in a dose-dependent manner. Besides, it could induce mitochondrial apoptosis. Epidermal growth factor receptor (EGFR) may be a potential target for GPS action in GC by network pharmacological analysis. GPS inhibits activation of the EGFR/PI3K/AKT axis by reducing EGFR expression. In vivo experiments indicated that GPS induced significant decrease in tumor volume, and it also inhibited the pulmonary metastasis. For the safety concerns, GPS caused no obvious toxicities to the heart, liver, spleen, lung and kidney tissues. IHC staining confirmed GPS downregulated the activity of EGFR/PI3K/AKT. CONCLUSIONS: Our investigation demonstrated for the first time that GPS could inhibit GC malignant progression by targeting the EGFR/PI3K/AKT signaling pathway. This study indicated that GPS may be serve as a safe anti-tumor drug for further treatment of GC.


Asunto(s)
Glucósidos Iridoides , Proteínas Proto-Oncogénicas c-akt , Neoplasias Gástricas , Animales , Ratones , Proteínas Proto-Oncogénicas c-akt/metabolismo , Neoplasias Gástricas/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Ratones Desnudos , Línea Celular Tumoral , Transducción de Señal , Receptores ErbB/metabolismo , Receptores ErbB/farmacología , Receptores ErbB/uso terapéutico , Proliferación Celular , Apoptosis
15.
Angew Chem Int Ed Engl ; 63(8): e202319876, 2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38183367

RESUMEN

Utilizing covalent organic framework (COF) as a hypotoxic and porous scaffold to encapsulate enzyme (enzyme@COF) has inspired numerous interests at the intersection of chemistry, materials, and biological science. In this study, we report a convenient scheme for one-step, aqueous-phase synthesis of highly crystalline enzyme@COF biocatalysts. This facile approach relies on an ionic liquid (2 µL of imidazolium ionic liquid)-mediated dynamic polymerization mechanism, which can facilitate the in situ assembly of enzyme@COF under mild conditions. This green strategy is adaptive to synthesize different biocatalysts with highly crystalline COF "exoskeleton", as well evidenced by the low-dose cryo-EM and other characterizations. Attributing to the rigorous sieving effect of crystalline COF pore, the hosted lipase shows non-native selectivity for aliphatic acid hydrolysis. In addition, the highly crystalline linkage affords COF "exoskeleton" with higher photocatalytic activity for in situ production of H2 O2 , enabling us to construct a self-cascading photo-enzyme coupled reactor for pollutants degradation, with a 2.63-fold degradation rate as the poorly crystalline photo-enzyme reactor. This work showcases the great potentials of employing green and trace amounts of ionic liquid for one-step synthesis of crystalline enzyme@COF biocatalysts, and emphasizes the feasibility of diversifying enzyme functions by integrating the reticular chemistry of a COF.


Asunto(s)
Disciplinas de las Ciencias Biológicas , Líquidos Iónicos , Estructuras Metalorgánicas , Polimerizacion , Lipasa
16.
Fitoterapia ; 172: 105770, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38056699

RESUMEN

Thirteen diterpenoids (1-13), classified into four structurally diverse carbon skeletons, including 1,5-seco-kalmane (1 and 6), grayanane (2-11), kalmane (12), and rhodomollane (13), were isolated from the flowers extract of Rhododendron molle. Among them, rhodomollinols A - E (1-5) were five new diterpenoids and their structures were elucidated by extensive spectroscopic methods including HRESIMS, UV, IR, 1D and 2D NMR, as well as quantum ECD calculations. Rhodomollinol A (1) is the first representative of a 6-deoxy-1,5-seco-kalmane diterpenoid. The abnormal NMR phenomenon of the presence of only 9 carbon resonances instead of 20 carbons in the 13C NMR spectrum of 1 was observed and elucidated by the quantum NMR calculations. All diterpenoids 1-13 showed significant analgesic activities in an acetic acid-induced writhing model. It's the first time to report the analgesic activity of a rhodomollane-type diterpenoid. At a dose of 1.0 mg/kg, diterpenoids 1-3, 6, 8, 9, and 12 reduced the writhe numbers with inhibition rates over 50%, and 9 exhibited stronger analgesic activity with a writhe inhibition rate of 89.7% than that of the positive control morphine. Importantly, even at the lowest dose of 0.04 mg/kg, rhodomollinols A (1) and B (2), rhodomollein X (7), and 2-O-methylrhodojaponin VI (9) still showed more potent analgesic effects than morphine with the writhe inhibition rates of 51.8%, 48.0%, 61.7%, and 60.0%, respectively. A preliminary structure-activity relationship might provide some clues to design potential analgesics on the basis of structurally diverse Ericaceae diterpenoids.


Asunto(s)
Diterpenos , Rhododendron , Rhododendron/química , Estructura Molecular , Flores/química , Analgésicos/farmacología , Diterpenos/farmacología , Diterpenos/química , Carbono/análisis , Derivados de la Morfina/análisis
17.
Am J Ophthalmol ; 258: 196-207, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37879454

RESUMEN

PURPOSE: This study seeks to evaluate the ability of the updated stress strain index (SSIv2) and other Corvis ST biomechanical parameters in distinguishing between keratoconus at different disease stages and normal eyes. DESIGN: Diagnostic accuracy analysis to distinguish disease stages. METHODS: 1084 eyes were included and divided into groups of normal (199 eyes), forme fruste keratoconus (FFKC, 194 eyes), subclinical keratoconus (SKC, 113 eyes), mild clinical keratoconus (CKC-Ⅰ, 175 eyes), moderate clinical keratoconus (CKC-Ⅱ, 204 eyes), and severe clinical keratoconus (CKC-Ⅲ, 199 eyes). Each eye was subjected to a Corvis ST examination to determine the central corneal thickness (CCT), biomechanically corrected intraocular pressure (bIOP), SSIv2 (updated stress-strain index), and other 8 Corvis parameters including the stress-strain index (SSIv1), stiffness parameter at first applanation (SP-A1), first applanation time (A1T), Ambrósio relational thickness to the horizontal profile (ARTh), integrated inverse radius (IIR), maximum deformation amplitude (DAM), ratio between deformation amplitude at the apex and at 2 mm nasal and temporal (DARatio2), and Corvis biomechanical index (CBI). The sensitivity and specificity of these parameters in diagnosing keratoconus were analyzed through receiver operating characteristic curves. RESULTS: Before and after correction for CCT and bIOP, SSIv2 and ARTh were significantly higher and IIR and CBI were significantly lower in the normal group than in the FFKC group, SKC group and the 3 CKC groups (all P < .05). There were also significant correlations between the values of SSIv2, ARTh, IIR, CBI, and the CKC severity (all P < .05). AUC of SSIv2 was significantly higher than all other Corvis parameters in distinguishing normal eyes from FFKC, followed by IIR, ARTh and CBI. CONCLUSION: Corvis ST's updated stress-strain index, SSIv2, demonstrated superior performance in differentiating between normal and keratoconic corneas, and between corneas with different keratoconus stages. Similar, but less pronounced, performance was demonstrated by the IIR, ARTh and CBI.


Asunto(s)
Queratocono , Humanos , Queratocono/diagnóstico , Topografía de la Córnea , Córnea , Tonometría Ocular , Presión Intraocular , Curva ROC , Fenómenos Biomecánicos
18.
Int J Biochem Cell Biol ; 166: 106503, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38036287

RESUMEN

INTRODUCTION: Interleukin-22 (IL-22) has been proven to exhibit a protective role in hepatic ischemia-reperfusion injury (HIRI). This study aimed to explore the change of IL-22 and IL-22 receptor 1 (IL-22R1) axis in HIRI and its role in mitochondrial apoptosis associated with STAT3 activation. MATERIALS AND METHODS: I/R mice were examined for the expression of IL-22, IL-22R1 and IL-22BP. The roles of IL-22 in hepatic histopathology and oxidative stress injuries (ALT, MDA and SOD) were determined. Oxidative stress damages of AML-12 cells were induced by H2O2, and were indicated by apoptosis, Ca2+ concentration, and mitochondrial function. The effects of IL-22 on p-STAT3Try705 were analyzed. RESULTS: We found that the expression of IL-22, IL-22R1, and IL-22BP was elevated 24 h after I/R induction, while decreased 48 h after I/R induction. Furthermore, we also discovered that IL-22 rescued the morphological damages and dysfunction of hepatocytes induced by H2O2, which were antagonized by IL-22BP, an endogenous antagonist of IL-22. Additionally, increased levels of Ca2+ concentration, MDA, ROS, apoptosis and mitochondrial dysfunction were noticed in H2O2-treated hepatocytes. However, IL-22 ameliorated the effects of I/R or H2O2. The protective effects of IL-22 were reversed by AG490, a specific antagonist of STAT3. CONCLUSIONS: In conclusion, our results indicated that IL-22 inhibited I/R-induced oxidative stress injury, Ca2+ overload, and mitochondrial apoptosis via STAT3 activation.


Asunto(s)
Interleucina-22 , Daño por Reperfusión , Animales , Ratones , Ratas , Apoptosis , Peróxido de Hidrógeno/farmacología , Peróxido de Hidrógeno/metabolismo , Hígado/metabolismo , Mitocondrias/metabolismo , Estrés Oxidativo , Ratas Sprague-Dawley , Daño por Reperfusión/metabolismo
19.
Bioorg Chem ; 142: 106928, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37922768

RESUMEN

A systematical investigation on the chemical constituents of the flowers of Rhododendron molle (Ericaceae) led to the isolation and characterization of thirty-eight highly functionalized grayanane diterpenoids (1-38), including twelve novel analogues molleblossomins A-L (1-12). Their structures were elucidated by comprehensive methods, including 1D and 2D NMR analysis, calculated ECD, 13C NMR calculations with DP4+ probability analysis, and single crystal X-ray diffraction. Molleblossomins A (1), B (2), and E (5) are the first representatives of 2ß,3ß:9ß,10ß-diepoxygrayanane, 2,3-epoxygrayan-9(11)-ene, and 5,9-epoxygrayan-1(10),2(3)-diene diterpenoids, respectively. Molleblossomins G (7) and H (8) represent the first examples of 1,3-dioxolane-grayanane conjugates furnished with the acetaldehyde and 4-hydroxylbenzylidene acetal moieties, respectively. All grayanane diterpenoids 1-38 were screened for their analgesic activities in the acetic acid-induced writhing model, and all of them exhibited significant analgesic activities. Diterpenoids 6, 13, 14, 17, 20, and 25 showed more potent analgesic effects than morphine at a lower dose of 0.2 mg/kg, with the inhibition rates of 51.4%, 68.2%, 94.1%, 66.9%, 97.7%, and 60.0%, respectively. More importantly, even at the lowest dose of 0.04 mg/kg, rhodomollein X (14), rhodojaponin VI (20), and rhodojaponin VII (22) still significantly reduced the number of writhes in the acetic acid-induced pain model with the percentages of 61.7%, 85.8%, and 64.6%, respectively. The structure-activity relationship was summarized and might provide some hints to design novel analgesics based on the functionalized grayanane diterpenoids.


Asunto(s)
Diterpenos , Rhododendron , Rhododendron/química , Estructura Molecular , Flores/química , Analgésicos/farmacología , Analgésicos/uso terapéutico , Analgésicos/química , Diterpenos/farmacología , Diterpenos/uso terapéutico , Diterpenos/química , Ácido Acético/análisis
20.
J Am Chem Soc ; 146(3): 1967-1976, 2024 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-38131319

RESUMEN

Engineering nanotraps to immobilize fragile enzymes provides new insights into designing stable and sustainable biocatalysts. However, the trade-off between activity and stability remains a long-standing challenge due to the inevitable diffusion barrier set up by nanocarriers. Herein, we report a synergetic interfacial activation strategy by virtue of hydrogen-bonded supramolecular encapsulation. The pore wall of the nanotrap, in which the enzyme is encapsulated, is modified with methyl struts in an atomically precise position. This well-designed supramolecular pore results in a synergism of hydrogen-bonded and hydrophobic interactions with the hosted enzyme, and it can modulate the catalytic center of the enzyme into a favorable configuration with high substrate accessibility and binding capability, which shows up to a 4.4-fold reaction rate and 4.9-fold conversion enhancements compared to free enzymes. This work sheds new light on the interfacial activation of enzymes using supramolecular engineering and also showcases the feasibility of interfacial assembly to access hierarchical biocatalysts featuring high activity and stability simultaneously.


Asunto(s)
Hidrógeno , Catálisis , Hidrógeno/química
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