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This study presents the development and validation of an innovative microfluidic liver-on-a-chip device utilizing gravity-driven perfusion for the evaluation of drug hepatotoxicity. This research involved the construction of a hydrogel-based coculture chip that integrates liver parenchymal and stellate cells within a tri-channel configuration. The assembly and operation of the liver-on-a-chip and its accompanying custom rocker were straightforward. The cells in the chip maintained high viability and continuously synthesized liver albumin over extended culture durations. Acetaminophen (APAP), a hepatic injury-inducing drug, was utilized as a positive control in hepatic toxicity assays on the chip. The liver chip exhibited hepatotoxic responses comparable to those observed in 2D models. Furthermore, in this study we evaluated the effects of two plant-derived natural compounds, aristolochic acid I (AA) and its analog aristolactam AII (AL), in both 2D cell models and the liver-on-a-chip system. AA, known for its hepatorenal toxicity, was observed to cause hepatotoxicity in both the 2D models and on the chip. The flow cytometry and mRNA sequencing results confirmed the propensity of these compounds to induce liver cell apoptosis. Notably, AL, previously considered nontoxic, provoked a significant decrease in the hepatic functionality marker albumin exclusively in the liver chip but not in 2D models, indicating the liver chip's enhanced sensitivity to toxic substances. In summary, this pumpless liver-on-a-chip is a simple yet powerful tool for drug hepatotoxicity studies.
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Micro-nano-plastic (MNP) particles (p) in the environment can enter the human body and pose a potential threat to human health. However, it is unknown whether these substances are present in polypropylene (PP) plastic-bottled injections, which are used as high-frequency intravenous infusions to treat diseases. Therefore, the objective of this study was to identify and quantify insoluble MNP particles in 16 batches of injectable formulations within the validity period. Primarily, ethylene-propylene copolymer or P(E-P) micro-plastic (MP) particles (2-10 µm, 216 p/mL) were identified by micro-Raman spectroscopy, and nano-particles (<50 nm, 2.1 × 104 p/mL) similar to PP containing only carbon were detected by scanning electron microscopy-energy-dispersive X-ray spectroscopy (photoelectron). Furthermore, P(E-P) MP particles (1 × 103 to 1 × 105 ng/L) from the injections were enriched on the GF-B filter, and PP or P(E-P) nano-plastic (NP) particles (1 × 103 to 4 × 104 ng/L) enriched on the alumina film were detected by pyrolysis-gas chromatography/mass spectrometry. Finally, the total insoluble particles in injections were 6 × 104 to 1 × 107 p/mL (0.02-100 µm). Our findings are the first to identify and quantify MNPs in PP-bottled injections. Considering that they can enter the blood circulation, so whether cause disease remains to be investigated.
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Microorganisms residing in the cecum of donkeys are crucial for physiological processes, nutrient metabolism, and immune function. Feeding methods can affect the dynamic balance of animal gut microbiota, thereby affecting indicators such as volatile fatty acids. This study explores suitable feeding methods to promote actual production by changing the feeding order of concentrate. Fifteen Dezhou donkeys with similar age and weight profiles were randomly divided into three groups with the concentrate feeding sequence: fiber-to-concentrate (FC), concentrate-to-fiber (CF), and total mixed ration (TMR). The experiment spanned a duration of 82 days. The analyses conducted were primarily aimed at determining the effects of feeding on gut microbes, primarily using metagenomic sequencing techniques. The experimental findings revealed that the levels of valeric acid were notably higher in the CF and TMR groups compared to the FC group (p < 0.05). These results suggest that the feeding sequence exerts a certain impact on the microbial composition within the cecum of Dezhou donkeys. At the phylum level, the predominant microbiota consisted of Firmicutes and Bacteroidetes, with the CF group displaying a higher relative abundance of Firmicutes compared to both the FC and TMR groups. At the genus level, Prevotella, Bacteroides, and Fibrobacter were the dominant bacterial genera identified in cecum. The functional gene annotation analysis indicated a significantly lower abundance of lacZ (K01190), Por/nifJ (K03737), and ppdK (K01006) genes in CF group relative to the FC and TMR groups (p < 0.05), highlighting their roles in galactose metabolism and glycolysis, respectively. Moreover, the CF group exhibited a higher concentration of antibiotic resistance genes (tetO and tet44) in the gut microbiota compared to the TMR and FC groups (p < 0.05), underscoring the presence of numerous antibiotic resistance genes within the phyla Bacteroidetes, Firmicutes, and Proteobacteria. In conclusion, different precision feed sequences significantly impact the levels of volatile fatty acids in Dezhou fattening donkeys, modify the composition and functional genes of the cecal microbiota, and elucidate the microbial mechanisms influenced by the feeding sequence on the growth and metabolism. These insights are anticipated to provide a foundation for the rational design of precision feed sequences in practical agricultural settings.
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Currently, an estimated 537 million individuals are affected by type 2 diabetes mellitus (T2DM), the occurrence of which is invariably associated with complications. Glucose-lowering therapy remains the main treatment for alleviating T2DM. However, conventional antidiabetic agents are fraught with numerous adverse effects, notably elevations in blood pressure and lipid levels. Recently, the use of traditional Chinese medicines (TCMs) and their constituents has emerged as a preferred management strategy aimed at curtailing the progression of diabetes and its associated complications with fewer adverse effects. Increasing evidence indicates that gut microbiome disturbances are involved in the development of T2DM and its complications. This regulation depends on various metabolites produced by gut microbes and their interactions with host organs. TCMs' interventions have demonstrated the ability to modulate the intestinal bacterial microbiota, thereby restoring host homeostasis and ameliorating metabolic disorders. This review delves into the alterations in the gut microbiota and metabolites in T2DM patients and how TCMs treatment regulates the gut microbiota, facilitating the management of T2DM and its complications. Additionally, we also discuss prospective avenues for research on natural products to advance diabetes therapy.
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Diabetes Mellitus Tipo 2 , Medicamentos Herbarios Chinos , Microbioma Gastrointestinal , Medicina Tradicional China , Humanos , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/microbiología , Microbioma Gastrointestinal/efectos de los fármacos , Medicamentos Herbarios Chinos/uso terapéutico , Medicamentos Herbarios Chinos/farmacología , Hipoglucemiantes/uso terapéutico , Hipoglucemiantes/farmacología , AnimalesRESUMEN
Sulfur-containing amino acids and peptides play critical roles in organisms. Thiol-ene reactions between the thiol residues of L-cysteine and the alkenyl fragments in the designed coupling partners serve as primary tools for constructing CâS bonds in the synthesis of unnatural sulfur-containing amino acid derivatives. These reactions are favored due to the preference for hydrogen transfer from thiol to ß-sulfanyl carbon radical intermediates. In this paper, the study proposes utilizing carbon-centered radicals stabilized by the capto-dative effect, generated under photocatalytic conditions from N-aryl glycine derivatives. The aim is to compete with the thiol hydrogen, enabling radical CâC bond formation with ß-sulfanyl carbon radicals. This protocol is robust in the presence of air and water, offers significant potential as a modular and efficient platform for synthesizing sulfur-containing amino acids and modifying peptides, particularly with abundant disulfides and styrenes.
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Carbono , Glicina , Péptidos , Estirenos , Azufre , Péptidos/química , Péptidos/síntesis química , Glicina/química , Glicina/análogos & derivados , Azufre/química , Carbono/química , Estirenos/química , Radicales Libres/química , CatálisisRESUMEN
Antibiotic-resistant pathogens have become a global public health crisis, especially biofilm-induced refractory infections. Efficient, safe, and biofilm microenvironment (BME)-adaptive therapeutic strategies are urgently demanded to combat antibiotic-resistant biofilms. Here, inspired by the fascinating biological structures and functions of phages, the de novo design of a spiky Ir@Co3O4 particle is proposed to serve as an artificial phage for synergistically eradicating antibiotic-resistant Staphylococcus aureus biofilms. Benefiting from the abundant nanospikes and highly active Ir sites, the synthesized artificial phage can simultaneously achieve efficient biofilm accumulation, extracellular polymeric substance (EPS) penetration, and superior BME-adaptive reactive oxygen species (ROS) generation, thus facilitating the in situ ROS delivery and enhancing the biofilm eradication. Moreover, metabolomics found that the artificial phage obstructs the bacterial attachment to EPS, disrupts the maintenance of the BME, and fosters the dispersion and eradication of biofilms by down-regulating the associated genes for the biosynthesis and preservation of both intra- and extracellular environments. The in vivo results demonstrate that the artificial phage can treat the biofilm-induced recalcitrant infected wounds equivalent to vancomycin. It is suggested that the design of this spiky artificial phage with synergistic "penetrate and eradicate" capability to treat antibiotic-resistant biofilms offers a new pathway for bionic and nonantibiotic disinfection.
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Antibacterianos , Bacteriófagos , Biopelículas , Especies Reactivas de Oxígeno , Biopelículas/efectos de los fármacos , Antibacterianos/farmacología , Antibacterianos/química , Especies Reactivas de Oxígeno/metabolismo , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/fisiología , Biocatálisis , Matriz Extracelular de Sustancias Poliméricas/metabolismo , Matriz Extracelular de Sustancias Poliméricas/química , Farmacorresistencia Bacteriana/efectos de los fármacos , AnimalesRESUMEN
OBJECTIVE: To compare the resting energy expenditure (REE) characteristics among young men with different body mass indexes (BMI). METHODS: Thirty young men [average age was (26.93±4.16) years] were enrolled in this study. They underwent resting metabolism tests in the Department of Sports Medicine of Peking University Third Hospital from December 2017 to June 2021. The resting metabolic rate (RMR) was measured by indirect calorimetry, the body composition was measured by bioresistance antibody component analyzer. The REE characteristics were analyzed, and 11 predictive equations were used to estimate RMR and compared with the measured value. The differences were analyzed by paired t-test and intra-class correlation coefficient (ICC). RESULTS: The RMR of the overall 30 young men was (1 960.17±463.11) kcal/d (1 kcal=4.186 8 kJ). Including (1 744.33±249.62) kcal/d in those with normal BMI, which was significantly lower than that in those who were overweight or obese [(2 104.06± 520.32) kcal/d, P < 0.01], but the weight-corrected RMR in those with normal BMI was significantly higher than that in those who were overweight or obese [(24.02±2.61) kcal/(kg·d) vs. (19.98±4.38) kcal/(kg·d), P < 0.01]. The RMR was significantly and positively correlated with body weight, adiposity, lean body mass, body surface area, and extracellular fluid in the subjects with diffe-rent BMI (all P < 0.05). The predicted values of the 11 prediction equations were not in good agreement with the measured values (all ICC < 0.75), with relatively high agreement between the predicted and measured values of the World Health Organization (WHO) equation in overweight obese young men (ICC=0.547, P < 0.01). CONCLUSION: There were significant differences in RMR among young men with different BMI, and the RMR after weight correction should be considered for those who were overweight or obese. The consistency between the predicted values of different prediction equations and the actual measured values of RMR was relatively poor, and it is recommended to accurately measure RMR by indirect calorimetry. For overweight or obese young men, the WHO prediction equation can be considered to calculate RMR, but it is necessary to establish an RMR prediction equation applicable to different BMI populations.
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Metabolismo Basal , Sobrepeso , Masculino , Humanos , Adulto Joven , Adulto , Índice de Masa Corporal , Sobrepeso/metabolismo , Obesidad , Metabolismo Energético , Composición CorporalRESUMEN
Background: Given the superior performance of various therapies over sorafenib in advanced hepatocellular carcinoma (HCC) and the absence of direct comparisons, it is crucial to explore the efficacy of these treatments in phase III randomized clinical trials. Objectives: The goal is to identify which patients are most likely to benefit significantly from these emerging therapies, contributing to more personalized and informed clinical decision-making. Design: Systematic review and network meta-analysis. Data sources and methods: PubMed, Embase, ClinicalTrials.gov, and international conference databases have been searched from 1 January 2010 to 1 December 2023. Results: After screening, 17 phase III trials encompassing 18 treatments were included. In the whole-population network meta-analysis, the newly first-line tremelimumab plus durvalumab (Tre + Du) was found to be comparable with atezolizumab plus bevacizumab (Atezo + Beva) in providing the best overall survival (OS) benefit [hazard ratio (HR) 1.35, 95% confidence interval (CI): 0.93-1.92]. Concerning OS benefits, sintilimab plus bevacizumab biosimilar (Sint + Beva), camrelizumab plus rivoceranib (Camre + Rivo), and lenvatinib plus pembrolizumab (Lenva + Pemb) appear to exhibit similar effects to Tre + Du and Atezo + Beva. In the context of progression-free survival, Atezo + Beva seemed to outperform Tre + Du (HR: 0.66 CI: 0.49-0.87), while the effects are comparable to Sint + Beva, Camre + Rivo, and Lenva + Pemb. Upon comparison between Asia-Pacific and non-Asia-Pacific cohorts, as well as between hepatitis B virus (HBV)-infected and non-HBV-infected populations, immune checkpoint inhibitor (ICI)-based treatments seemed to exhibit heightened efficacy in the Asia-Pacific group and among individuals with HBV infection. However, combined ICI-based therapies did not show more effectiveness than molecular-targeted drugs in patients without macrovascular invasion and/or extrahepatic spread. As for grades 3-5 adverse events, combined therapies showed comparable safety to sorafenib and lenvatinib. Conclusion: Compared with sorafenib and lenvatinib, combination therapies based on ICIs significantly improved the prognosis of advanced HCC and demonstrated similar safety. At the same time, the optimal treatment approach should be tailored to individual patient characteristics, such as etiology, tumor staging, and serum alpha-fetoprotein levels. With lower incidence rates of treatment-related adverse events and non-inferior efficacy compared to sorafenib, ICI monotherapies should be prioritized as a first-line treatment approach for patients who are not suitable candidates for ICI-combined therapies. Trial registration: PROSPERO, CRD42022288172.
Lay summary/Key points The efficiency of various systemic therapies in advanced HCC patients with specific characteristics remains to be explored. This study revealed that the efficacy of ICI combined therapies is influenced by factors such as tumor staging, etiology, patient demographics, and more. Additionally, ICI monotherapies should be prioritized as a first-line treatment approach for patients who are not suitable candidates for ICI combined therapies. Complementing to recent guidelines, this study indicated that several critical factors needed to be took into consideration for patients with advanced HCC.
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Atherosclerosis is featured as chronic low-grade inflammation in the arteries, which leads to the formation of plaques rich in lipids. M2 macrophage-derived extracellular vesicles (M2EV) have significant potential for anti-atherosclerotic therapy. However, their therapeutic effectiveness has been hindered by their limited targeting capability in vivo. The objective of this study was to create the P-M2EV (platelet membrane-modified M2EV) using the membrane fusion technique in order to imitate the interaction between platelets and macrophages. P-M2EV exhibited excellent physicochemical properties, and microRNA (miRNA)-sequencing revealed that the extrusion process had no detrimental effects on miRNAs carried by the nanocarriers. Remarkably, miR-99a-5p was identified as the miRNA with the highest expression level, which targeted the mRNA of Homeobox A1 (HOXA1) and effectively suppressed the formation of foam cells in vitro. In an atherosclerotic low-density lipoprotein receptor-deficient (Ldlr-/-) mouse model, the intravenous injection of P-M2EV showed enhanced targeting and greater infiltration into atherosclerotic plaques compared to regular extracellular vesicles. Crucially, P-M2EV successfully suppressed the progression of atherosclerosis without causing systemic toxicity. The findings demonstrated a biomimetic platelet-mimic system that holds great promise for the treatment of atherosclerosis in clinical settings.
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Calcific aortic valve disease is a prevalent cardiovascular disease with no available drugs capable of effectively preventing its progression. Hence, an efficient drug delivery system could serve as a valuable tool in drug screening and potentially enhance therapeutic efficacy. However, due to the rapid blood flow rate associated with aortic valve stenosis and the lack of specific markers, achieving targeted drug delivery for calcific aortic valve disease has proved to be challenging. Here we find that protease-activated-receptor 2 (PAR2) expression is up-regulated on the plasma membrane of osteogenically differentiated valvular interstitial cells. Accordingly, we develop a magnetic nanocarrier functionalized with PAR2-targeting hexapeptide for dual-active targeting drug delivery. We show that the nanocarriers effectively deliver XCT790-an anti-calcification drug-to the calcified aortic valve under extra magnetic field navigation. We demonstrate that the nano-cargoes consequently inhibit the osteogenic differentiation of valvular interstitial cells, and alleviate aortic valve calcification and stenosis in a high-fat diet-fed low-density lipoprotein receptor-deficient (Ldlr-/-) mouse model. This work combining PAR2- and magnetic-targeting presents an effective targeted drug delivery system for treating calcific aortic valve disease in a murine model, promising future clinical translation.
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Estenosis de la Válvula Aórtica , Calcinosis , Ratones , Animales , Válvula Aórtica/metabolismo , Estenosis de la Válvula Aórtica/tratamiento farmacológico , Osteogénesis , Calcinosis/tratamiento farmacológico , Calcinosis/metabolismo , Células Cultivadas , Fenómenos MagnéticosRESUMEN
Side chain engineering plays a vital role in exploring high-performance small molecule acceptors (SMAs) for organic solar cells (OSCs). In this work, we designed and synthesized a series of A-DA'D-A type SMAs by introducing different N-substituted alkyl and ester alkyl side chains on benzotriazole (BZ) central unit and aimed to investigate the effect of different ester substitution positions on photovoltaic performances. All the new SMAs with ester groups exhibit lower the lowest unoccupied molecular orbital (LUMO) energy levels and more blue-shifted absorption, but relatively higher absorption coefficients than alkyl chain counterpart. After blending with the donor PM6, the ester side chain-based devices demonstrate enhanced charge mobility, reduced amorphous intermixing domain size and long-lived charge transfer state compared to the alkyl chain counterpart, which are beneficial to achieve higher short-circuit current density (Jsc ) and fill factor (FF), simultaneously. Thereinto, the PM6 : BZ-E31 based device achieves a higher power conversion efficiency (PCE) of 18.33 %, which is the highest PCE among the OSCs based on the SMAs with BZ-core. Our work demonstrated the strategy of ester substituted side chain is a feasible and effective approach to develop more efficient SMAs for OSCs.
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Carboxylic functionalities are among the pivotal groups in bioactive molecules and in the synthesis of new lead compounds because of their unique character in the formation of hydrogen bonds and the possibility of constructing molecular complexes via amide couplings. We adopt the reductive radical-polar crossover strategy to introduce carboxyalkyl groups into arenes with styrenes and CO2 via thianthrenium salts. This protocol exhibits excellent potential as a straightforward and modular platform for site-selective carboxylative derivation of bioactive molecules.
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With the sharp rise of antibiotic-resistant pathogens worldwide, it is of enormous importance to create new strategies for combating pathogenic bacteria. Here, we create an iron oxide-based spiky artificial peroxidase (POD) with V-O-Fe pair sites (V-Fe2 O3 ) for combating methicillin-resistant Staphylococcus aureus (MRSA). The experimental studies and theoretical calculations demonstrate that the V-Fe2 O3 can achieve the localized "capture and killing" bifunction from the spiky morphology and massive reactive oxygen species (ROS) production. The V-Fe2 O3 can reach nearly 100 % bacterial inhibition over a long period by efficiently oxidizing the lipid membrane. Our wound disinfection results identify that the V-Fe2 O3 can not only efficiently eliminate MRSA and their biofilm but also accelerate wound recovery without causing noticeable inflammation and toxicity. This work offers essential insights into the critical roles of V-O-Fe pair sites and localized "capture and killing" in biocatalytic disinfection and provides a promising pathway for the de novo design of efficient artificial peroxidases.
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Antibacterianos , Staphylococcus aureus Resistente a Meticilina , Antibacterianos/farmacología , Peroxidasas , BiopelículasRESUMEN
Objective:To observe the effect of electroacupuncture(EA)combined with routine language and motor training on limb and language function,depression,and serum brain injury markers in patients with ischemic stroke. Methods:A total of 86 patients with ischemic stroke were selected and divided into an observation group and a control group using the random drawing method,with 43 cases in each group.Both groups received routine stroke treatments.The control group was additionally treated with routine language and motor training,and the observation group was additionally treated with EA treatment on the basis of the intervention of the control group.Changes in the limb function score,language function score,depression score,and brain injury marker protein were compared between the two groups,and the treatment safety of the two groups was evaluated. Results:The Fugl-Meyer assessment scale scores of both groups were higher than those before treatment(P<0.05),and the Fugl-Meyer assessment scale score of limb function of the observation group was higher than that of the control group(P<0.05).The language function score of the observation group was higher than that of the control group after treatment(P<0.05).The Montgomery-Asberg depression rating scale(MADRS)scores of the observation group were lower than those of the control group after treatment(P<0.05).The levels of brain injury markers heart-type fatty acid-binding protein(H-FABP),glial fibrillary acidic protein(GFAP),and annexin a7(ANXA7)of the observation group were lower than those of the control group(P<0.05).The incidence rate of adverse reactions in the two groups was 14.0%and 9.3%,respectively,with no statistically significant difference between the groups(P>0.05). Conclusion:EA combined with language and motor training is effective in the treatment of ischemic stroke.It can promote the recovery of limb motor function and language function,inhibit the occurrence of depression,and reduce the levels of brain injury markers,with good safety.
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PURPOSE: To explore the effects of allicin on insulin resistance and free fatty acids (FFAs) levels in obese rats with periodontitis. METHODS: Forty rats were randomly divided into healthy group, periodontitis group, and low, medium and high dose groups, with 8 rats in each group. The healthy group was healthy rats, and the other groups were induced by sodium glutamate(MSG). After successfully establishing an obesity model, the maxillary molars were ligated and smeared to establish a periodontitis model. Both the periodontitis group and the healthy group were given normal saline, and the allicin low, medium and high dose groups were given allicin 20ï¼40 and 60 mg·kg-1·d-1, mixed with feed for oral administration. After 21 days of treatment, the fasting blood glucose(FPG), fasting insulin (FINS), insulin resistance index (HOMA-IR) scores and FFAs levels of the homeostatic model in rats were detected. The protein expression of TLR4/MyD88 signaling pathway were compared. Statistical analysis was performed with SPSS 22.0 software package. RESULTS: Compared with the healthy group, FPG, FINS levels, HOMA-IR, IL-6 and TNF-α levels of the periodontitis group were significantly increased, and the expression of TLR4 and MyD88 proteins was significantly increased(Pï¼0.05). Compared with the periodontitis group, FPG, FINS levels, HOMA-IR, IL-6 and TNF-α levels of low, medium and high-doses groups were significantly decreased, and the expression of TLR4 and MyD88 proteins was significantly decreased (Pï¼0.05). Compared with the low-dose group, the levels of FPG and FINS, HOMA-IR, IL-6 and TNF-α levels of the middle and high-dose groups were significantly decreased, and the expression of TLR4 and MyD88 proteins was significantly decreased (Pï¼0.05). Compared with the middle-dose group, the levels of FPG and FINS, HOMA-IR, IL-6 and TNF-α levels of the high-dose group were significantly decreased, and the expression of TLR4 and MyD88 proteins was significantly decreased (Pï¼0.05). After treatment, FFAs of the low, medium and high-dose groups were significantly lower than those before treatment(Pï¼0.05). Compared with the healthy group, FFAs levels of the periodontitis group, low-dose and medium-dose groups were significantly increased. Compared with the periodontitis group, FFAs levels of the low, medium and high-dose groups were significantly increased. Compared with the low-dose group, FFAs levels of the high-dose group were significantly increased. Compared with the middle-dose group, FFAs levels of the high-dose group were significantly increased (Pï¼0.05). CONCLUSIONS: Allicin can improve insulin resistance and obesity in obese rats with periodontitis, and its mechanism of action is related to the TLR4/MyD88 signaling pathway.
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Resistencia a la Insulina , Periodontitis , Ratas , Animales , Ácidos Grasos no Esterificados , Factor de Necrosis Tumoral alfa/metabolismo , Interleucina-6/metabolismo , Receptor Toll-Like 4/metabolismo , Factor 88 de Diferenciación Mieloide/metabolismo , Obesidad/metabolismo , Insulina/metabolismoRESUMEN
A practical method that enables the fluorosulfenylation of unactivated alkenes processed directly with thiols and fluoride salts is presented. Good to excellent efficiencies and functional group tolerance are observed for both alkene substrates and thiols. The procedure also allows the use of gaseous ethylene as a two-carbon building block for ß-fluoro thioether products.
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An unexpected deprotonative process of thiirenium ions is presented, which provides a new synthesis of aryl thioalkynes directly from terminal alkynes via the electrophilic activation of the carbon-carbon triple bonds. The conditions are well compatible with various functional-group-substituted aryl alkynes. The direct elimination from the thiirenium ion intermediate, or its tautomer, benzyl vinyl carbocation, is supported by control experiments and labeling reaction.
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In this study, effects on the growth performance, nutrient digestibility, volatile fatty acids (VFA) production, and fecal microbiota of weaned donkeys were observed using different concentrate feeding sequences. Fifteen healthy 6-month-old weaned male donkeys with a body weight of 117.13 ± 10.60 kg were randomly divided into three treatment groups, including group C1 (roughage-then-concentrate), group C2 (concentrate-then-roughage), and group C3 (total mixed ration, TMR). The experiment lasted 35 d. We measured nutrient digestion by the acid-insoluble ash method and analyzed the fecal microbiota of the weaned donkeys by high-throughput sequencing of 16s rRNA genes in the V3-V4 region. The results show that group C3 obtained the best growth performance, and the digestibility of crude protein (CP) and crude extract (EE) was significantly higher than that of group C1 (p < 0.05). Acetic acid, isobutyric acid, valeric acid, isovaleric acid, and caproic acid were notably different among all groups (p < 0.05). In addition, we observed that Firmicutes and Bacteroidetes were dominant in the fecal microbes of each group, and Firmicutes was significantly higher in group C3 (p < 0.05). At the genus level, the different genera were Treponema, Rikenellaceae-RC9-gut-group, Unidentified-F082, and Bacteroidales-RF16-group (p < 0.05). The prediction of fecal microbiota function by PICRUSt indicated that different feeding sequences had minimal impact on the function of the fecal microbiota, particularly on the high-abundance pathway. In summary, the concentrate feeding sequence changed the composition of the fecal microbe of weaned donkeys.
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Tetraphenylethylene (TPE)-based ligands are appealing for constructing metal-organic frameworks (MOFs) with new functions and responsiveness. Here, we report a non-interpenetrated TPE-based scu Zr-MOF with anisotropic flexibility, that is, Zr-TCPE (H4TCPE = 1,1,2,2-tetra(4-carboxylphenyl)ethylene), remaining two anisotropic pockets. The framework flexibility is further anisotropically rigidified by installing linkers individually at specific pockets. By individually installing dicarboxylic acid L1 or L2 at pocket A or B, the framework flexibility along the b-axis or c-axis is rigidified, and the intermolecular or intramolecular motions of organic ligands are restricted, respectively. Synergistically, with dual linker installation, the flexibility is completely rigidified with the restriction of ligand motion, resulting in MOFs with enhanced stability and improved separation ability. Furthermore, in situ observation of the flipping of the phenyl ring and its rigidification process is made by 2H solid-state NMR. The anisotropic rigidification of flexibility in scu Zr-MOFs guides the directional control of ligand motion for designing stimuli-responsive emitting or efficient separation materials.
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The proliferation and differentiation of skeletal muscle satellite cells (SCs) are necessary for the development of mature skeletal muscle. Leucine (Leu) is both an essential amino acid (EAA) and a branched-chain amino acid (BCAA), which has attracted worldwide attention due to its ability to repair and become new fibers. We separated the equine SCs into the control group (CON) and the Leu-supplemented group (LEU), which the cells were cultured in Leu-deprived and Leu-supplemented media respectively. We combined the transcriptome (RNA-Seq) and quantitative proteome (TMT) profiling analyses on proliferation of equine SCs associated with Leu. 1839 up-regulated and 631 down-regulated genes made up the 2470 differentially expressed genes (DEGs), and the 253 differentially abundant proteins (DEPs) included 118 up-regulated and 135 down-regulated proteins. 110 overlapping genes were verified based on the mRNA and protein translation relationship. Moreover, by comparing overlapped pathways through enrichment analysis, we found 13 genes not only appeared among 110 key DEGs/DEPs but also enriched in the KEGG overlapping signaling pathway, including CCL26, STAT2, PCK2, ASNS, GPT2, SHMT2, PHGDH, PGAM2, PSAT1, FTL, HMOX1, STEAP1 and STEAP2. To our knowledge, this is the first report in the world to systematically show how Leu regulated the growth of equine SCs. Leu deficiency inhibits the proliferation of equine SCs and development of fresh muscle fibers was proved in this paper. The main genes in charge of the Leu-induced proliferation of horse SCs have been found. These genes will make it easier to understand the mechanism at work and offer new information for enhancing the performance of sport horses and alleviating the equine muscle damage during exercise in the future.