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Antimony smelting activities damage the soil and vegetation surroundings while generating economic value. However, no standardized methods are available to diagnose the extent of soil degradation at antimony smelting sites. This study developed a standardized framework for assessing soil quality by considering microbial-induced resilience and heavy metal contamination at Xikuangshan antimony smelting site. The soil resilience index (SRI) and soil contamination index (SCI) were calculated by Minimum Data Set and geo-accumulation model, respectively. After standardized by a multi-criteria quantitative procedure of modified Nemerow's pollution index (NPI), the integrated assessment of soil quality index (SQI), which is the minimum of SRINPI and SCINPI, was achieved. The results showed that Sb and As were the prominent metal(loid) pollutants, and significant correlations between SQI and SRI indicated that the poor soil quality was mainly caused by the low level of soil resilience. The primary limiting factors of SRI were Fungi in high and middle contaminated areas, and Skermanella in low contaminated area, suggesting that the weak soil resilience was caused by low specific microbial abundances. Microbial regulation and phytoremediation are greatly required to improve the soil quality at antimony smelting sites from the perspectives of pollution control and resilience improvement. This study improves our understanding of ecological effects of antimony smelting sites and provides a theoretical basis for ecological restoration and sustainable development of mining areas.
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Antimonio , Monitoreo del Ambiente , Metales Pesados , Microbiología del Suelo , Contaminantes del Suelo , Suelo , Contaminantes del Suelo/análisis , Antimonio/análisis , Monitoreo del Ambiente/métodos , Metales Pesados/análisis , Suelo/química , Metalurgia , Biodegradación Ambiental , ChinaRESUMEN
Indigenous microbial communities in smelting areas are crucial for maintaining fragile ecosystem functions. However, the community assembly process and their responses to polymetallic pollution are poorly understood, especially the taxa in each bin from the amplicons that contributed to the assembly process. Herein, microbial diversity, co-occurrence patterns, assembly process and the intrinsic mechanisms across contamination gradients at a typical PbZn smelting site were systematically unravelled by high-throughput sequencing. The results showed a consistent compositional profile among the indigenous communities across sampling sites, wherein genera KD4-96 from Chloroflexi and Sphingomonas from Proteobacteria emerged as the most abundant taxa. Network modularity of the high- and middle-contaminated communities at Pb and Zn smelting sites was >0.44, indicating that community populations were clustered into modules to resist high heavy metal stress. Stochastic processes dominated the community assembly, with the greatest contribution from drift (DR), which was significantly correlated with Pb, Zn, Cr and Cu contents. What's particular was that the DR-controlled bins were dominated by Proteobacteria (typical r-strategists), while the HoS-controlled bins were by Chloroflexi (typical K-strategists). Furthermore, the proportion of DR in the bins dominated by Sphingomonadaceae (phylum Proteobacteria) increased gradually with the increase of heavy metal contents. These discoveries provide essential insights for community control in restoring and mitigating soil degradation at PbZn smelting sites.
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Plomo , Microbiota , Microbiología del Suelo , Contaminantes del Suelo , Zinc , Contaminantes del Suelo/análisis , Plomo/análisis , Zinc/análisis , Procesos Estocásticos , Metalurgia , Monitoreo del Ambiente , Metales Pesados/análisis , Bacterias/clasificación , Bacterias/genéticaRESUMEN
Background: The immune-inflammatory pathway plays a critical role in myocardial infarction development. However, few studies have systematically explored immune-related genes in relation to myocardial infarction prognosis using bioinformatic analysis. Our study aims to identify differentially expressed immune-related genes(DEIRGs) in ST-segment elevation myocardial infarction (STEMI) patients and investigate their association with clinical outcomes. Materials and methods: We conducted a systematic review of Gene Expression Omnibus datasets, selecting GSE49925, GSE60993, and GSE61144 for analysis. DEIRGs were identified using GEO2R and overlapped across the chosen datasets. Functional enrichment analysis elucidated the DEIRGs' biological functions and pathways. We established an optimal prognostic prediction model using LASSO penalized Cox proportional hazards regression. The signature's clinical utility was evaluated through survival analysis, ROC curve assessment, and decision curve analysis. Additionally, we constructed a prognostic nomogram for survival rate prediction. External validation was performed using our own plasma samples. Results: The resulting prognostic signature integrated two dysregulated DEIRGs (S100A12 and IL2RB) and two clinical variables (serum creatinine level and Gensini score). This signature effectively stratified patients into low- and high-risk groups. Survival analysis, ROC curve analysis, and decision curve analysis demonstrated its robust predictive performance and clinical utility within the first two years post-disease onset. External validation confirmed significant outcome differences between risk groups. Conclusions: Our study establishes a prognostic signature that combines DEIRGs and clinical variables for STEMI patients. The signature exhibits promising predictive capabilities for patient stratification and survival risk assessment.
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Investigating the structure-property correlation in porous materials is a fundamental and consistent focus in various scientific domains, especially within sorption research. Metal oxide clusters with capping ligands, characterized by intrinsic cavities formed through specific solid-state packing, demonstrate significant potential as versatile platforms for sorption investigations due to their precisely tunable atomic structures and inherent long-range order. This study presents a series of Ti8Ce2-oxo clusters with subtle variations in coordinated linkers and explores their sorption behavior. Notably, Ti8Ce2-BA (BA denotes benzoic acid) manifests a distinctive two-step profile during the CO2 adsorption, accompanied by a hysteresis loop. This observation marks a new instance within the metal oxide cluster field. Of intrigue, the presence of unsaturated Ce(IV) sites was found to be correlated with the stepped sorption property. Moreover, the introduction of an electrophilic fluorine atom, positioned ortho or para to the benzoic acid, facilitated precise control over gate pressure and stepped sorption quantities. Advanced in situ techniques systematically unraveled the underlying mechanism behind this unique sorption behavior. The findings elucidate that robust Lewis base-acid interactions are established between the CO2 molecules and Ce ions, consequently altering the conformation of coordinated linkers. Conversely, the F atoms primarily contribute to gate pressure variation by influencing the Lewis acidity of the Ce sites. This research advances the understanding in fabricating metal-oxo clusters with structural flexibility and provides profound insights into their host-guest interaction motifs. These insights hold substantial promise across diverse fields and offer valuable guidance for future adsorbent designs grounded in fundamental theories of structure-property relationships.
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Titanium-oxo clusters, with their robust structure and suitable optical and electronic properties, have been widely investigated as photocatalysts. Heterometallic Ti/M-oxo clusters provide additional tunability and functionality, which enable systematic structure-activity investigations to elucidate the reaction mechanisms and improve the catalyst design. Incorporating cerium into Ti-oxo clusters can provide additional redox (CeIV/CeIII) and oxygen harvesting ability, but to date, only a limited number of structurally defined titanium-cerium (Ti/Ce) clusters have been reported due to their synthetic challenges. Herein, we report the synthesis and photocatalytic properties of two structurally defined Ti/Ce-oxo clusters, Ti8Ce2(BA)16 and Ti9Ce4(BA)20, as well as a TiCe-BA cluster with a calculated formula of Ti20Ce9O36(BA)42. Photocatalytic study of these clusters demonstrates that the amount of Ce3+ species greatly impacts its photocatalytic oxidation performance, and their superior photocatalytic reactivity toward aerobic alcohol oxidation can be contributed to the synergistic effects of the multiple radical species generated upon light absorption. This work represents a significant milestone in the construction of stable Ti/Ce-oxo clusters, enriching the current library of known heterometallic Ti/M-oxo clusters, and providing a series of crystalline materials with great promise of photoluminescence and photovoltaic chemistry.
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The use of histone deacetylase inhibitors (HDACis) is an effective approach for cancer treatment. In this work, a series of hydroxamic acid-based HDACis with a tetrahydro-ß-carboline core and aliphatic linker have been designed and synthesized. The optimal compound 13d potently inhibited HDAC1 and showed good antiproliferative activity against different tumor cell lines in vitro. Molecular docking of 13d was conducted to rationalize the high binding affinity for HDAC1. Therefore, this work provides a new structure design for HDAC inhibitors and also offers a promising treatment for solid tumors.
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Phthalate acid esters (PAEs) and their metabolites, such as di-n-butyl phthalate (DBP) and mono-n-butyl phthalate (MBP), are known to cause male reproductive damage. Lactiplantibacillus plantarum RS20D has demonstrated the ability to remove both DBP and MBP in vitro, suggesting its potential as a detoxifying agent against these compounds. This study aimed to investigate the protective effects of RS20D on DBP or MBP-induced male reproductive toxicity in adolescent rats. Oral administration of RS20D significantly mitigated the histological damage to the testes caused by MBP or DBP, restored sperm concentration, morphological abnormalities, and the proliferation index in MBP-exposed rats, and partially reversed spermatogenic damage in DBP-exposed rats. Furthermore, RS20D restored serum levels of estradiol (E2) and testosterone, and superoxide dismutase (SOD) activity in DBP-exposed rats, significantly increased testosterone levels in MBP-exposed rats, and restored copper (Cu) concentrations in the testes after exposure to DBP or MBP. Additionally, RS20D effectively modulated the intestinal microbiota in DBP-exposed rats and partially ameliorated dysbiosis induced by MBP, which may be associated with the alleviation of reproductive toxic effects induced by DBP or MBP. In conclusion, this study demonstrates that RS20D administration can alleviate male reproductive toxicity and gut dysbacteriosis induced by DBP or MBP exposure, providing a dietary strategy for the bioremediation of PAEs and their metabolites.
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Sichuan bacon represents the most prevalent dry-cured meat product across Southwest China, but it is vulnerable to fungal spoilage. In the present study, a total of 47 Sichuan bacons were obtained from different regions of the Sichuan Province and analyzed for the presence of ochratoxin A (OTA), yielding a positive rate of 23.4 % (11/47). All the observed OTA concentrations exceeded the maximum admissible dose in meat products (1 µg/kg) established by some EU countries, with the highest OTA concentration being 250.75 µg/kg, which raises a food safety concern and reveals the need for a standardized scientific processing protocol. Then, an OTA-producing fungus named 21G2-1A was isolated from positive samples and found to be Aspergillus westerdijkiae. Further characterization suggested a positive correlation between fungal growth and OTA production. The optimal temperature for the former was 25 °C, while it was 20 °C for the latter. Although the A. westerdijkiae strain 21G2-1A demonstrated greater mycelium growth in the presence of NaCl, OTA production was significantly dismissed when the salinity was greater than 5 %. Four lactic acid bacteria (LAB) were screened out as antagonists against the ochratoxigenic fungus. In vitro evaluation of the antagonists revealed that live cells inhibited fungal growth, and adsorption also contributed to OTA removal at different levels. This study sheds some light on OTA control in Sichuan bacon through a biological approach.
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Ocratoxinas , Carne de Cerdo , Adsorción , AspergillusRESUMEN
Objective: Abdominal wall hernias are common abdominal diseases, and effective hernia repair is challenging. In clinical practice, synthetic meshes are widely applied for repairing abdominal wall hernias. However, postoperative complications, such as inflammation and adhesion, are prevalent. Although biological meshes can solve this problem to a certain extent, they face the problems of heterogeneity, rapid degradation rate, ordinary mechanical properties, and high-cost. Here, a novel electrospinning mesh composed of polylactic acid and silk fibroin (PLA-SF) for repairing abdominal wall hernias was manufactured with good physical properties, biocompatibility and low production cost. Materials and methods: FTIR and EDS were used to demonstrate that the PLA-SF mesh was successfully synthesized. The physicochemical properties of PLA-SF were detected by swelling experiments and in vitro degradation experiments. The water contact angle reflected the hydrophilicity, and the stressâstrain curve reflected the mechanical properties. A rat abdominal wall hernia model was established to observe degradation, adhesion, and inflammation in vivo. In vitro cell mesh culture experiments were used to detect cytocompatibility and search for affected biochemical pathways. Results: The PLA-SF mesh was successfully synthesized and did not swell or degrade over time in vitro. It had a high hydrophilicity and strength. The PLA-SF mesh significantly reduced abdominal inflammation and inhibited adhesion formation in rat models. The in vitro degradation rate of the PLA-SF mesh was slower than that of tissue remodeling. Coculture experiments suggested that the PLA-SF mesh reduced the expression of inflammatory factors secreted by fibroblasts and promoted fibroblast proliferation through the TGF-ß1/Smad pathway. Conclusion: The PLA-SF mesh had excellent physicochemical properties and biocompatibility, promoted hernia repair of the rat abdominal wall, and reduced postoperative inflammation and adhesion. It is a promising mesh and has potential for clinical application.
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Muscaris is a modern white grape variety with good fungal resistance and a pleasant aroma, the molecular background of which was unknown. A comparative aroma extract dilution analysis applied to Muscaris grapes and grapes of the father variety Muskateller revealed little differences and resulted in 39 and 35 odorants, respectively. Sixteen odorants exceeded their odor threshold concentrations. Odor reconstitution and omission experiments showed that the distinct lychee note in the aroma of the Muscaris grapes was generated by the combination of (2S,4R)-rose oxide and geraniol. This finding will guide further molecular research on the transfer of the lychee note into wine and may also be helpful for the targeted breeding of new grape varieties.
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Asparagaceae , Litchi , Vitis , Compuestos Orgánicos Volátiles , Vino , Odorantes/análisis , Olfato , Fitomejoramiento , Vino/análisis , Compuestos Orgánicos Volátiles/análisisRESUMEN
To evaluate the effect and its mechanism of heat-resistant antimicrobial peptide LLv on broilers, three hundred 1-day-old healthy AA+ female broilers were allocated into 5 groups with 6 replicates in each group and 10 birds in each replicate. Birds were given a basal diet, an antibiotic diet (10.2 mg/kg chlortetracycline hydrochloride), and the basal diet supplemented with 10, 50, and 100 mg/kg LLv for 42 d, respectively. Compared with the group which birds were fed an antibiotic-free basal diet (control group), supplementing 100 mg/kg LLv increased 21-day IgA, IgM, IL-4, AIV-Ab, IFN-γ levels and 42-day IgA, IgM, IL-4, AIV-Ab levels and reduced 42-day IL-1 levels in serum (P < 0.05). Compared with antibiotic group, the 10 and 50 mg/kg LLv decreased 42-day IgM levels in serum (P < 0.05). The 100 mg/kg LLv increased 21-day AIV-Ab levels and 42-day IL-4, AIV-Ab levels and reduced 42-day IL-1 levels in serum (P < 0.05). Compared with control group, the 100 mg/kg LLv increased the expression rate of sIgA secretory cells and sIgA content in jejunal mucosa at 21 d and 42 d (P < 0.05), which did not differ from antibiotic group (P > 0.05). Compared with antibiotic group, the 10 mg/kg LLv reduced 21-day sIgA content and the 50 mg/kg LLv reduced 42-d the expression rate of sIgA secretory cells in jejunal mucosa (P < 0.05). Compared with control group, the 100 mg/kg LLv increased the expression of TCR, IL-15, CD28, BAFF, CD86, CD83, MHC-II, and CD40 genes in jejunal mucosa at 21 d and 42 d (P < 0.05). Compared with antibiotic group, the 100 mg/kg LLv increased the expression of 21-day BAFF, CD40, MHC-II, CD83 genes and the expression of 42-day BAFF, TCR, IL-15, CD40, CD83 genes in jejunal mucosa (P < 0.05). The results showed that the addition of LLv to the ration had a promotional effect on the immune function of broiler chickens.
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Pollos , Interleucina-15 , Animales , Femenino , Interleucina-4/genética , Suplementos Dietéticos , Dieta/veterinaria , Antibacterianos/farmacología , Inmunoglobulina M , Inmunoglobulina A Secretora , Interleucina-1 , Inmunoglobulina A , Receptores de Antígenos de Linfocitos T , Alimentación Animal/análisisRESUMEN
Okra polysaccharides exhibits a range of biological activities. To date, its processing using microbial fermentation has not been explored. This study investigated the fermentation of okra juice with various lactic acid bacteria, followed by the extraction and characterization of crude polysaccharides (termed OPS-F), in contrast to their non-fermented counterpart (OPS). Changes in physicochemical properties, antioxidant activity and immunomodulatory ability were noted. The results demonstrated that OPS-F had a 7.42-12.53 % increase in total polysaccharides content compared to OPS. However, high-performance size-exclusion chromatography indicated a reduction in the molecular weight of OPS-F (7.9-9.5 × 105 Da) relative to OPS (1.66 × 106 Da). Compared to OPS, OPS-F had reduced levels of mannose, glucose, glucuronic acid and arabinose, but increased rhamnose, galacturonic acid and galactose, exhibiting enhanced solubility and lower apparent viscosity. Fourier transform infrared spectroscopy and nuclear magnetic resonance analysis showed minimal changes in polysaccharide structure post-fermentation. Moreover, despite a decrease in antioxidant activity post-fermentation, OPS-F exhibited superior immunomodulatory potential. In conclusion, fermenting okra juice with lactic acid bacteria alters the physicochemical properties of crude polysaccharides and enhances their immunomodulatory activity, offering a promising approach for developing new functional food resources.
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Abelmoschus , Antioxidantes , Antioxidantes/farmacología , Antioxidantes/química , Abelmoschus/química , Fermentación , Polisacáridos/farmacología , Polisacáridos/química , Peso MolecularRESUMEN
BACKGROUND: Postoperative abdominal adhesion (PAA) is a common postoperative complication. Clinically, various methods have been used to prevent the occurrence of PAA, such as drugs and physiotherapy; however, no satisfactory results have been obtained. Luteolin (LUT) is a natural flavonoid that reduces inflammation and acts as an antioxidant. This research aimed to examine the impact and mechanism of LUT in reducing PAA. METHODS: C57/BL6 mice were used in vivo experiments. PAA model was established using a brush friction method. Visual scoring and hematoxylin and eosin staining were used to score the severity of adhesions. Network pharmacology was used to infer potential targets and core pathways of LUT. Hydrogen peroxide (H2O2) was used to induce oxidative stress in vitro, while the reactive oxygen species (ROS) assay kit was used to evaluate oxidative stress levels. Western blotting, cell immunofluorescence, and multiple immunofluorescence assays were used to detect α-SMA, vimentin, E-cadherin, collagen I, or AKT phosphorylation level. Scratch assay was used to detect cell migration. RESULTS: LUT reduced the degree of PAA in mice. It attenuated H2O2-induced ROS production and reversed mesothelial-mesenchymal transition (MMT) in HMrSV5 cells. Network pharmacology analysis showed that LUT likely exerted anti-adhesion activity by regulating the PI3K-Akt signaling pathway. Phosphorylated Akt levels were significantly reduced in LUT-treated HMrSV5 cells. LUT also significantly reduced the expression of vimentin and collagen I in adherent tissues and upregulated E-cadherin expression. CONCLUSION: LUT blocks the ROS/PI3K/AKT pathway, thereby inhibiting MMT and reducing PAA. To this end, LUT has potential in PAA therapy.
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Luteolina , Fosfatidilinositol 3-Quinasas , Proteínas Proto-Oncogénicas c-akt , Animales , Ratones , Cadherinas/metabolismo , Colágeno , Peróxido de Hidrógeno/farmacología , Luteolina/farmacología , Luteolina/uso terapéutico , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Vimentina/metabolismoRESUMEN
Traditional low earth orbit (LEO) satellite networks are typically independent of terrestrial networks, which develop relatively slowly due to the on-board capacity limitation. By integrating emerging mobile edge computing (MEC) with LEO satellite networks to form the business-oriented "end-edge-cloud" multi-level computing architecture, some computing-sensitive tasks can be offloaded by ground terminals to satellites, thereby satisfying more tasks in the network. How to make computation offloading and resource allocation decisions in LEO satellite edge networks, nevertheless, indeed poses challenges in tracking network dynamics and handling sophisticated actions. For the discrete-continuous hybrid action space and time-varying networks, this work aims to use the parameterized deep Q-network (P-DQN) for the joint computation offloading and resource allocation. First, the characteristics of time-varying channels are modeled, and then both communication and computation models under three different offloading decisions are constructed. Second, the constraints on task offloading decisions, on remaining available computing resources, and on the power control of LEO satellites as well as the cloud server are formulated, followed by the maximization problem of satisfied task number over the long run. Third, using the parameterized action Markov decision process (PAMDP) and P-DQN, the joint computing offloading, resource allocation, and power control are made in real time, to accommodate dynamics in LEO satellite edge networks and dispose of the discrete-continuous hybrid action space. Simulation results show that the proposed P-DQN method could approach the optimal control, and outperforms other reinforcement learning (RL) methods for merely either discrete or continuous action space, in terms of the long-term rate of satisfied tasks.
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BACKGROUND: Intestinal ischemia-reperfusion injury occurs in acute intestinal obstruction, intussusception, acute mesenteric artery embolism, and other diseases and can lead to local intestinal necrosis, distant organ involvement, or systemic reactions, with high morbidity and mortality. Ferroptosis plays a crucial role in intestinal ischemia-reperfusion injury, and inhibition of ferroptosis may provide new approaches for treating the disease. SIRT3 protects cells from oxidative stress and may be involved in the process of ferroptosis. We hypothesized that resveratrol, an agonist of SIRT3, could ameliorate intestinal ischemia-reperfusion injury by compensating the GSH/GPX4 pathway. METHODS: Intestinal ischemia-reperfusion (I/R) and Caco-2 hypoxia-reoxygenation models were established. Transmission electron microscopy was used to assess mitochondrial function; the Chiu's score was used to evaluate the degree of intestinal mucosal injury based on HE staining; and Western blot was used to detect the SIRT3/FoxO3a pathway, tight junction proteins and ferroptosis-related protein expression. Sirt3-/- C57, shSIRT3-Caco-2 cells and siFoxO3a-Caco-2 cells were established. C11-BODIPY was used to detect lipid peroxide in cells; FD4 and IFABP were used to detect intestinal permeability; MitoSOX was used to detect ROS levels; and MitoTracker and immunofluorescence colocalization were used to detect SIRT3 levels. RESULTS: In the intestinal I/R model, I/R injury occurs mainly during the reperfusion period and leads to ferroptosis through the GSH/GPX4 pathway. Resveratrol could reduce ferroptosis and ameliorate I/R injury by activating SIRT3. In Sirt3-/- mice, more intestinal mucosal cells underwent ferroptosis, I/R injury was more severe, and resveratrol lost the ability to ameliorate I/R injury. In addition, hypoxia-reoxygenation increased RSL3-induced ferroptosis sensitivity in Caco-2 cells in vitro. In the presence of shSIRT3 or RSL3 alone, resveratrol could ameliorate Caco-2 ferroptosis, but not RSL3-induced shSIRT3-Caco-2 ferroptosis. Furthermore, resveratrol might activate the SIRT3/FoxO3a pathway, increase the expression of SOD2 and catalase, and inhibit ROS generation, thus reducing lipid peroxidation and ferroptosis. CONCLUSION: To date, this is the first study to show that resveratrol ameliorates intestinal ischemia-reperfusion injury by activating SIRT3 and reducing ferroptosis. Resveratrol can reduce intestinal ischemia-reperfusion injury by activating the SIRT3/FoxO3a pathway, increasing the expression of SOD2 and catalase, reducing ROS and LPO production, compensating for the GSH/GPX4 pathway and inhibiting ferroptosis. Resveratrol increases the expression of SOD2 and catalase, reduces the production of ROS and LPO, compensates for the GSH/GPX4 pathway and inhibits ferroptosis by activating the SIRT3/FoxO3a pathway.
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Ferroptosis , Daño por Reperfusión , Sirtuina 3 , Humanos , Ratones , Animales , Resveratrol/farmacología , Especies Reactivas de Oxígeno/metabolismo , Catalasa , Sirtuina 3/genética , Sirtuina 3/metabolismo , Células CACO-2 , Daño por Reperfusión/tratamiento farmacológico , Daño por Reperfusión/metabolismo , HipoxiaRESUMEN
Metal-organic frameworks (MOFs) that contain open metal sites have the potential for storing hydrogen (H2) at ambient temperatures. In particular, Cu(I)-based MOFs demonstrate very high isosteric heats of adsorption for hydrogen relative to other reported MOFs with open metal sites. However, most of these Cu(I)-based MOFs are not stable in ambient conditions since the Cu(I) species display sensitivity toward moisture and can rapidly oxidize in air. As a result, researchers have focused on the synthesis of new air-stable Cu(I)-based materials for H2 storage. Here, we have developed a de novo synthetic strategy to generate a robust Cu(I)-based MOF, denoted as NU-2100, using a mixture of Cu/Zn precursors in which zinc acts as a catalyst to transform an intermediate MOF into NU-2100 without getting incorporated into the final MOF structure. NU-2100 is air-stable and displays one of the initial highest isosteric heats of adsorption (32 kJ/mol) with good hydrogen storage capability under ambient conditions (10.4 g/L, 233 K/100 bar to 296 K/5 bar). We further elucidated the H2 storage performance of NU-2100 using a combination of spectroscopic analysis and computational modeling studies. Overall, this new synthetic route may enable the design of additional stable Cu(I)-MOFs for next-generation hydrogen storage adsorbents at ambient temperatures.
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While uranyl-based metal-organic frameworks (MOFs) boast impressive photocatalytic abilities, significant questions remain regarding their excitation pathways and methods to fine-tune their performance due to the lack of information regarding heterogeneous uranyl catalysis. Herein, we investigated how linker identity and photoexcitation impact uranyl photocatalysis when the uranyl coordination environment remains constant. Toward this end, we prepared three uranyl-based MOFs (NU-1301, NU-1307, and ZnTCPP-U2) and then examined the structural and photochemical properties of each through X-ray diffraction, X-ray absorption, and photoluminescence. We then correlated our observations to the photocatalytic performance for fluorination of cyclooctane. The excitation profile from NU-1301 and NU-1307 exhibited spin-forbidden linker transitions and uranyl vibronic progressions, with uranyl excitation and emission being most dominant in NU-1301. Consequently, NU-1301 was a more active photocatalyst than NU-1307. In contrast, the excitation profile from ZnTCPP-U2 contained transitions associated with the porphyrin linker exclusively. Photocatalytic activity from ZnTCPP-U2 significantly underperformed in comparison to that of the other two MOFs. These data suggest that linkers' photophysical properties can be used to predict the photocatalytic behavior of uranyl-containing MOFs.
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The presence of cypermethrin in the environment and food poses a significant threat to human health. Lactic acid bacteria have shown promise as effective absorbents for xenobiotics and well behaved in wide range of applications. This study aimed to characterize the biosorption behavior of cypermethrin by Lactiplantibacillus plantarum RS60, focusing on cellular components, functional groups, kinetics, and isotherms. Results indicated that RS60 exopolysaccharides played a crucial role removing cypermethrin, with the cell wall and protoplast contributing 71.50% and 30.29% to the overall removal, respectively. Notably, peptidoglycans exhibited a high affinity for cypermethrin binding. The presence of various cellular surface groups including -OH, -NH, -CH3, -CH2, -CH, -P = O, and -CO was responsible for the efficient removal of pollutants. Additionally, the biosorption process demonstrated a good fit with pseudo-second-order and Langmuir-Freundlich isotherm. The biosorption of cypermethrin by L. plantarum RS60 involved complex chemical and physical interactions, as well as intraparticle diffusion and film diffusion. RS60 also effectively reduced cypermethrin residues in a fecal fermentation model, highlighting its potential in mitigating cypermethrin exposure in humans and animals. These findings provided valuable insights into the mechanisms underlying cypermethrin biosorption by lactic acid bacteria and supported the advancement of their application in environmental and health-related contexts. KEY POINTS: ⢠Cypermethrin adsorption by L. plantarum was clarified. ⢠Cell wall and protoplast showed cypermethrin binding ability. ⢠L. plantarum can reduce cypermethrin in a fecal fermentation model.
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Proteins play important roles in the therapeutic, medical diagnostic, and chemical catalysis industries. However, their potential is often limited by their fragile and dynamic nature outside cellular environments. The encapsulation of proteins in solid materials has been widely pursued as a route to enhance their stability and ease of handling. Nevertheless, the experimental investigation of protein interactions with rationally designed synthetic hosts still represents an area in need of improvement. In this work, we leveraged the tunability and crystallinity of metal-organic frameworks (MOFs) and developed a series of crystallographically defined protein hosts with varying chemical properties. Through systematic studies, we identified the dominating mechanisms for protein encapsulation and developed a host material with well-tailored properties to effectively encapsulate the protein ubiquitin. Specifically, in our mesoporous hosts, we found that ubiquitin encapsulation is thermodynamically favored. A more hydrophilic encapsulation environment with favorable electrostatic interactions induces enthalpically favored ubiquitin-MOF interactions, and a higher pH condition reduces the intraparticle diffusion barrier, both leading to a higher protein loading. Our findings provide a fundamental understanding of host-guest interactions between proteins and solid matrices and offer new insights to guide the design of future protein host materials to achieve optimal protein loading. The MOF modification technique used in this work also demonstrates a facile method to develop materials easily customizable for encapsulating proteins with different surface properties.
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Estructuras Metalorgánicas , Ubiquitina , Catálisis , Difusión , Electricidad EstáticaRESUMEN
The interactions between uranium and non-innocent organic species are an essential component of fundamental uranium redox chemistry. However, they have seldom been explored in the context of multidimensional, porous materials. Uranium-based metal-organic frameworks (MOFs) offer a new angle to study these interactions, as these self-assembled species stabilize uranium species through immobilization by organic linkers within a crystalline framework, while potentially providing a method for adjusting metal oxidation state through coordination of non-innocent linkers. We report the synthesis of the MOF NU-1700, assembled from U4+ -paddlewheel nodes and catecholate-based linkers. We propose this highly unusual structure, which contains two U4+ ions in a paddlewheel built from four linkers-a first among uranium materials-as a result of extensive characterization via powder X-ray diffraction (PXRD), sorption, transmission electron microscopy (TEM), and thermogravimetric analysis (TGA), in addition to density functional theory (DFT) calculations.