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Introduction Escherichia coli (E. coli) is a significant commensal gram-negative bacterium that can give rise to various diseases. The roles of Toll-like receptor 2 (TLR2) and the NLR pyrin domain-containing 3 (NLRP3) inflammasome in sepsis induced by E. coli infection remain unclear. Methods In vivo, we investigated differences in mortality, production of inflammatory mediators, organ damage, neutrophil count, and bacterial load during E. coli infection in C57BL/6J mice, as well as in mice deficient in TLR2 or NLRP3. In vitro, we investigated the impact of E. coli on the activation of TLR2 and NLRP3 in macrophages and the influence of TLR2 and NLRP3 on the activation of inflammatory signaling pathways and the secretion of inflammatory mediators in macrophages induced by E. coli infection. Results TLR2-deficient (TLR2-/-) and NLRP3-deficient (NLRP3-/-) mice exhibit significantly increased mortality and organ damage after E. coli infection. These mice also show elevated levels of TNF-α and IL-10 in serum and peritoneal lavage fluid (PLF). Additionally, TLR2-/- and NLRP3-/- mice display heightened neutrophil recruitment, increased bacterial load in the blood. Furthermore, macrophages from these mice demonstrate a significant reduction in the activation of the MAPK signaling pathway. Conclusion TLR2 and NLRP3 play crucial roles in modulating inflammatory mediator expression, immune cell recruitment, and bactericidal activity, thereby preventing excessive tissue damage and reducing mortality in E. coli-induced sepsis.
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Green hydrogen energy from electrocatalytic hydrogen evolution reactions (HERs) has gained much attention for its advantages of low carbon, high efficiency, interconnected energy medium, safety, and controllability. Non-precious metals have emerged as a research hotspot for replacing precious metal catalysts due to low cost and abundant reserves. However, maintaining the stability of non-precious metals under harsh conditions (e.g., strongly acidic, alkaline environments) remains a significant challenge. By leveraging the curling properties of two-dimensional materials, a new class of catalysts, encapsulating transition metal nanoparticles inside carbon (TM@C) chainmail, has been successfully developed. This catalyst can effectively isolate the active metal from direct contact with harsh reaction media, thereby delaying catalyst deactivation. Furthermore, the electronic structure of the carbon layer can be regulated through the transfer of electrons, which stimulates its catalytic activity. This addresses the issue of the insufficient stability of traditional non-precious metal catalysts. This review commences with a synopsis of the synthetic advancement of the engineering of TM@C chainmail catalysts. Thereafter, a critical discussion ensues regarding the electrocatalytic performance of TM@C chainmail catalysts during hydrogen production. Ultimately, a comprehensive review of the conformational relationship between the structure of TM@C chainmail catalysts and HER activity is provided, offering substantial support for the large-scale application of hydrogen energy.
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α-Cyanostilbene represents one of the easily functionalized aggregation-induced emission (AIE) scaffolds. It has been widely adopted for the construction of fluorescent materials for broad applications. Here, we further expanded the utilization of α-cyanostilbene derivatives for the detection of hypoxia or proteostasis imbalance in live cells. Four different amine containing donors were introduced to construct α-cyanostilbene derivatives (R-ASC) with donor-acceptor scaffolds. Equipped with the cysteine (Cys) reactive group, maleimide (MI), R-ASC-MI shows fluorescence turn-on property upon binding with unfolded proteins in vitro and in live cells under proteostatic stress. By virtue of R-ASC-MI, the level of unfolded protein loads in cells can be quantified by flow cytometry, or visualized under microscope. Furthermore, we also characterized the performance of R-ASC-NO2, synthetic precursors of R-ASC-MI, in cellular hypoxia. R-ASC-NO2 revealed upregulated activities of nitroreductase, as well as increased hydrophobicity in live cells, under either chemical (NaN3) induced or atmospheric (1% O2) hypoxia. Together, the advantages of easy modification and high signal-to-noise ratio of new α-cyanostilbene derivatives reported in this work highlight the great potential of α-cyanostilbene in constructing functional biosensors and many other domains.
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BACKGROUND: Chronic atrophic gastritis (CAG) is an important precursor of gastric cancer(GC), and there is currently a lack of reliable non-invasive diagnostic markers. This study aims to find a biomarker for non-invasive screening of CAG in the community. METHODS: A total of 540 individuals were enrolled (test set = 385, validation set = 155). ROC curve analysis was used to evaluate the diagnostic significance of serum Trefoil Factor 3 (TFF3) alone or in combination with pepsinogen (PG) for CAG in the test and validation set. Furthermore, the diagnostic value of TFF3 and PG in different Helicobacter pylori (H. pylori) infection states was studied. RESULTS: When compared with chronic superficial gastritis (CSG), the expression level of serum TFF3 in the CAG was higher (27 ng/ml vs 19.61, P < 0.001). ROC curve analysis found that the sensitivity, specificity, and area under the curve (AUC) of CAG diagnosis using serum TFF3 alone at the optimal cut-off value of 26.55 ng/ml were 0.529, 0.87, and 0.739, respectively. When TFF3 was combined with The Ratio of PGI to PGII (PGR), the AUC and specificity reached 0.755 and 0.825, respectively. TFF3 individual or combined with PGR had good predictive value, especially in the H. Pylori negative patients. CONCLUSION: TFF3 combined with PGR can effectively predict CAG, especially in patients with H. pylori negative.
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Gastrite Atrófica , Infecções por Helicobacter , Pepsinogênio A , Neoplasias Gástricas , Fator Trefoil-3 , Humanos , Gastrite Atrófica/sangue , Gastrite Atrófica/diagnóstico , Fator Trefoil-3/sangue , Pepsinogênio A/sangue , Neoplasias Gástricas/sangue , Neoplasias Gástricas/diagnóstico , Estudos Retrospectivos , Masculino , Feminino , Pessoa de Meia-Idade , Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/sangue , Curva ROC , Helicobacter pylori , Detecção Precoce de Câncer/métodos , Adulto , Idoso , Biomarcadores/sangue , Sensibilidade e Especificidade , Doença CrônicaRESUMO
Acute lung injury (ALI) is a significant clinical problem associated with high morbidity and mortality. Inflammation induced by gram-positive bacterial pathogens, specifically Staphylococcus aureus (S. aureus), plays a major role in ALI development and other infectious diseases. Taurochenodeoxycholic acid (TCDCA) exhibits diverse biological activities and pharmacological effects. Nevertheless, the potential preventive and therapeutic effects of TCDCA and the underlying mechanism in the ALI induced by S. aureus infection remain poorly understood. Our results showed that the TCDCA (0.1 µg/g) had a beneficial effect on lung damage in mice infected with S. aureus. Specifically, TCDCA could lead to a reduction in pulmonary focal or diffuse oedema and a decrease in the infiltration of neutrophils in the S. aureus-infected lungs. We observed that TCDCA could significantly down-regulate the expression of HMGB1 in lung from S. aureus-infected mice. Furthermore, TCDCA could attenuate the production of inflammatory mediators in lungs and serum from S. aureus-infected mice. This finding further supported the notion that TCDCA potentially protects against tissue injury. In addition, TCDCA regulated the secretion of the proinflammatory cytokine, the activation of MAPK and NF-κB signaling pathways, and the activation of TLR2 in macrophages. Notably, TCDCA might reduce the secretion levels of inflammatory mediators and lung damage through the TLR2 in S. aureus-infected macrophages or mice. Altogether, TCDCA shows promise as a potential drug for preventing and treating ALI by modulating or inhibiting inflammatory mediators through TLR2.
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Lesão Pulmonar Aguda , Proteína HMGB1 , Pulmão , Infecções Estafilocócicas , Staphylococcus aureus , Ácido Tauroquenodesoxicólico , Receptor 2 Toll-Like , Animais , Receptor 2 Toll-Like/metabolismo , Lesão Pulmonar Aguda/tratamento farmacológico , Lesão Pulmonar Aguda/microbiologia , Lesão Pulmonar Aguda/etiologia , Lesão Pulmonar Aguda/imunologia , Lesão Pulmonar Aguda/patologia , Staphylococcus aureus/efeitos dos fármacos , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/imunologia , Camundongos , Proteína HMGB1/metabolismo , Ácido Tauroquenodesoxicólico/farmacologia , Ácido Tauroquenodesoxicólico/uso terapêutico , Pulmão/patologia , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Pulmão/microbiologia , Masculino , NF-kappa B/metabolismo , Anti-Inflamatórios/uso terapêutico , Anti-Inflamatórios/farmacologia , Citocinas/metabolismo , Camundongos Endogâmicos C57BL , Transdução de Sinais/efeitos dos fármacos , Células RAW 264.7 , HumanosRESUMO
BACKGROUND: Chronic atrophy gastritis (CAG) is a high-risk pre-cancerous lesion for gastric cancer (GC). The early and accurate detection and discrimination of CAG from benign forms of gastritis (e.g. chronic superficial gastritis, CSG) is critical for optimal management of GC. However, accurate non-invasive methods for the diagnosis of CAG are currently lacking. Cytokines cause inflammation and drive cancer transformation in GC, but their utility as a diagnostic for CAG is poorly characterized. METHODS: Blood samples were collected, and 40 cytokines were quantified using a multiplexed immunoassay from 247 patients undergoing screening via endoscopy. Patients were divided into discovery and validation sets. Each cytokine importance was ranked using the feature selection algorithm Boruta. The cytokines with the highest feature importance were selected for machine learning (ML), using the LightGBM algorithm. RESULTS: Five serum cytokines (IL-10, TNF-α, Eotaxin, IP-10 and SDF-1a) that could discriminate between CAG and CSG patients were identified and used for predictive model construction. This model was robust and could identify CAG patients with high performance (AUC = 0.88, Accuracy = 0.78). This compared favorably to the conventional approach using the PGI/PGII ratio (AUC = 0.59). CONCLUSION: Using state-of-the-art ML and a blood-based immunoassay, we developed an improved non-invasive screening method for the detection of precancerous GC lesions. FUNDING: Supported in part by grants from: Jiangsu Science and Technology Project (no. BK20211039); Top Talent Support Program for young and middle-aged people of Wuxi Health Committee (BJ2023008); Medical Key Discipline Program of Wuxi Health Commission (ZDXK2021010), Wuxi Science and Technology Bureau Project (no. N20201004); Scientific Research Program of Wuxi Health Commission (Z202208, J202104).
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Citocinas , Gastrite Atrófica , Aprendizado de Máquina , Humanos , Feminino , Masculino , Citocinas/sangue , Pessoa de Meia-Idade , Gastrite Atrófica/sangue , Gastrite Atrófica/diagnóstico , Neoplasias Gástricas/sangue , Neoplasias Gástricas/diagnóstico , Idoso , Adulto , Detecção Precoce de Câncer/métodos , Doença CrônicaRESUMO
The utilization of residual sludge by microalgae represents an environmentally sustainable method for resource recovery. In this study, Tetradesmus obliquus was cultured in hydrolysate derived from toxic sludge. Under symbiotic conditions with bacteria, Tetradesmus obliquus demonstrated enhanced toxin degradation capability and biomass accumulation, which exhibited a 1.39-fold increase in algal cell density, a 1.50-fold increase in Rubisco activity, and a total protein content of 341.83 ± 6.99 mg/L on the 30th day of cultivation. Metabolic utilization of substances in the hydrolysate by microalgae led to a toxicity removal rate of up to 60.43% by day 10. Phenylalanine showed the most significant increase among essential amino acids, and transcriptomic profiling identified genes (gene_16399, gene_16602) involved in phenylalanine enrichment. Macrotranscriptomics showed that bacteria upregulated the TCS system and tryptophan metabolism, supplying microalgae with more CO2 and IAA, which enhanced amino acid enrichment. This study established a non-toxic and biomass-accumulating bacterial-algal co-cultivation system.
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BACKGROUND: Prediabetes has been found to be associated with an elevated overall risk of cancer, which may be site-specific. we performed a protocol for systematic review and meta-analysis to investigate the correlation between prediabetes and the incidence of gastric cancer (GC). METHODS: A thorough review of the literature was conducted in the PubMed, Embase, and Web of Science databases to identify pertinent observational studies with longitudinal follow-up. The random-effects model was employed to consolidate the data, taking into account the potential impact of heterogeneity. RESULTS: A total of 13 datasets from 8 prospective cohort studies were included. The prevalence of prediabetes was 9.6%. During the mean follow-up duration of 7.1 to 12.2 years, 33,135 patients were diagnosed with GC. According to the results of the pooled analysis, prediabetes was associated with a mildly higher incidence of GC over time (risk ratio: 1.07, 95% confidence interval: 1.01-1.13, Pâ =â .03; I2â =â 44%). Subsequent subgroup analyses indicated that the relationship between prediabetes and the heightened risk of GC may not be substantially influenced by factors such as the country in which the study was conducted, the average age of participants, their gender, the definition of prediabetes used, the prevalence of prediabetes at the beginning of the study, the incidence of GC within the studied population, or the adjustment made for body mass index (P for subgroup difference all >.05). CONCLUSION: The presence of prediabetes may increase the risk of GC by a mild amount when compared with people with normoglycemia in community-derived adult populations.
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Estado Pré-Diabético , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/epidemiologia , Estado Pré-Diabético/epidemiologia , Incidência , Fatores de Risco , Prevalência , Masculino , FemininoRESUMO
Hen egg low-density lipoprotein (heLDL), as alternative of serum-derived LDL, was used as drug delivery system of ceftiofur (CEF). The CEF-loaded hen egg low-density lipoprotein (CEF-heLDL) with complete apolipoprotein structure and high drug loading rate was synthesized, possesses suitable particle size. CEF-heLDL undergoes cellular uptake and colocalizes with lysosomes in vitro. An intracellular infection model of the bovine endometrial epithelial cells and a coeliac-induced inflammation model of mice by Staphylococcus aureus (S. aureus) were established, and significantly lower intracellular S. aureus levels of CEF-heLDL group than CEF-free group (P < 0.001) was observed. The antibacterial efficacy was sustained for 24 h. Up to 400 mg/kg of CEF-heLDL, 20 times the clinical practice, were intraperitoneally administrated, and no significant toxicity signs on mice were observed. HeLDLs is an effective, safe, and cheap drug carrier, and could also be used for transmembrane delivering other antibiotics.
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Antibacterianos , Cefalosporinas , Galinhas , Lipoproteínas LDL , Staphylococcus aureus , Animais , Staphylococcus aureus/efeitos dos fármacos , Lipoproteínas LDL/metabolismo , Antibacterianos/farmacologia , Antibacterianos/química , Camundongos , Cefalosporinas/farmacologia , Cefalosporinas/farmacocinética , Cefalosporinas/química , Bovinos , Feminino , Portadores de Fármacos/química , Infecções Estafilocócicas/tratamento farmacológico , OvosRESUMO
Inflammation is the response of the human body to injury, infection, or other abnormal states, which is involved in the development of many diseases. As a member of the Krüppel-like transcription factors (KLFs) family, KLF4 plays a crucial regulatory role in physiological and pathological processes due to its unique dual domain of transcriptional activation and inhibition. A growing body of evidence has demonstrated that KLF4 plays a pivotal role in the pathogenesis of various inflammatory disorders, including inflammatory bowel disease, osteoarthritis, renal inflammation, pneumonia, neuroinflammation, and so on. Consequently, KLF4 has emerged as a promising new therapeutic target for inflammatory diseases. This review systematically generalizes the molecular regulatory network, specific functions, and mechanisms of KLF4 to elucidate its complex roles in inflammatory diseases. An in-depth study on the biological function of KLF4 is anticipated to offer a novel research perspective and potential intervention strategies for inflammatory diseases.
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Inflamação , Fator 4 Semelhante a Kruppel , Fatores de Transcrição Kruppel-Like , Animais , Humanos , Anti-Inflamatórios/uso terapêutico , Inflamação/metabolismo , Inflamação/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Fatores de Transcrição Kruppel-Like/genéticaRESUMO
In vivo muscle architectural parameters can be calculated from the fiber tracts using magnetic resonance (MR) tractography. However, the reconstructed tracts may be unevenly distributed within the muscle volume and there lacks commonly used metric to quantitatively evaluate the validity of the tracts. Our objective is to measure forearm muscle architecture by uniformly sampling fiber tracts from the candidate streamlines in MR tractography and validate the reconstructed fiber tracts qualitatively and quantitatively. We proposed farthest streamline sampling (FSS) to uniformly sample fiber tracts from the candidate streamlines. The method was evaluated on the MR data acquired from 12 healthy subjects for 17 forearm muscles and was compared with two conventional methods through uniform coverage performance. Anatomical correctness was verified by: 1. visually assessing fiber orientation, 2. checking whether architectural parameters were within physiological ranges and 3. classifying architectural types. The proposed FSS yielded optimal uniform coverage performance among the three methods (P<0.05). FSS reduced the sampling of long tracts (10% fiber length reduction, P<0.05), and the estimated architectural parameters were within the physiological ranges (P<0.05). The tractography visually matched cadaveric specimens. The architectural types of 16 muscles were correctly classified except for the palmaris longus, which exhibited a linear arrangement of fiber endpoints (R2 = 0.95±0.02, P<0.001). The proposed FSS method reconstructed uniformly distributed fiber tracts and the anatomical correctness of the reconstructed tracts was verified. The novel methods allow for accurate in vivo muscle architectural measurement, which was demonstrated through the characterization of architectural properties in human forearm muscles.
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Neuromechanical studies investigate how the nervous system interacts with the musculoskeletal (MSK) system to generate volitional movements. Such studies have been supported by simulation models that provide insights into variables that cannot be measured experimentally and allow a large number of conditions to be tested before the experimental analysis. However, current simulation models of electromyography (EMG), a core physiological signal in neuromechanical analyses, remain either limited in accuracy and conditions or are computationally heavy to apply. Here, we provide a computational platform to enable future work to overcome these limitations by presenting NeuroMotion, an open-source simulator that can modularly test a variety of approaches to the full-spectrum synthesis of EMG signals during voluntary movements. We demonstrate NeuroMotion using three sample modules. The first module is an upper-limb MSK model with OpenSim API to estimate the muscle fibre lengths and muscle activations during movements. The second module is BioMime, a deep neural network-based EMG generator that receives nonstationary physiological parameter inputs, like the afore-estimated muscle fibre lengths, and efficiently outputs motor unit action potentials (MUAPs). The third module is a motor unit pool model that transforms the muscle activations into discharge timings of motor units. The discharge timings are convolved with the output of BioMime to simulate EMG signals during the movement. We first show how MUAP waveforms change during different levels of physiological parameter variations and different movements. We then show that the synthetic EMG signals during two-degree-of-freedom hand and wrist movements can be used to augment experimental data for regressing joint angles. Ridge regressors trained on the synthetic dataset were directly used to predict joint angles from experimental data. In this way, NeuroMotion was able to generate full-spectrum EMG for the first use-case of human forearm electrophysiology during voluntary hand, wrist, and forearm movements. All intermediate variables are available, which allows the user to study cause-effect relationships in the complex neuromechanical system, fast iterate algorithms before collecting experimental data, and validate algorithms that estimate non-measurable parameters in experiments. We expect this modular platform will enable validation of generative EMG models, complement experimental approaches and empower neuromechanical research.
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Biologia Computacional , Eletromiografia , Movimento , Músculo Esquelético , Eletromiografia/métodos , Humanos , Movimento/fisiologia , Músculo Esquelético/fisiologia , Redes Neurais de Computação , Fenômenos Biomecânicos/fisiologia , Simulação por Computador , Potenciais de Ação/fisiologia , Modelos NeurológicosRESUMO
Escherichia coli (E. coli), a Gram-negative bacterium, is the primary pathogen responsible for endometritis in dairy cattle. The outer membrane components of E. coli, namely lipopolysaccharide (LPS) and bacterial lipoprotein, have the capacity to trigger the host's innate immune response through pattern recognition receptors (PRRs). Tolerance to bacterial cell wall components, including LPS, may play a crucial role as an essential regulatory mechanism during bacterial infection. However, the precise role of Braun lipoprotein (BLP) tolerance in E. coli-induced endometritis in dairy cattle remains unclear. In this study, we aimed to investigate the impact of BLP on the regulation of E. coli infection-induced endometritis in dairy cattle. The presence of BLP was found to diminish the expression and release of proinflammatory cytokines (IL-8 and IL-6), while concurrently promoting the expression and release of the anti-inflammatory cytokine IL-10 in endometrial epithelial cells (EECs). Furthermore, BLP demonstrated the ability to impede the activation of MAPK (ERK and p38) and NF-κB (p65) signaling pathways, while simultaneously enhancing signaling through the STAT3 pathway in EECs. Notably, BLP exhibited a dual role, acting both as an activator of TLR2 and as a regulator of TLR2 activation in LPS- and E. coli-treated EECs. In E. coli-infected endometrial explants, the presence of BLP was noted to decrease the release of proinflammatory cytokines and the expression of HMGB1, while simultaneously enhancing the release of anti-inflammatory cytokines. Collectively, our findings provide evidence that the bacterial component BLP plays a protective role in E. coli-induced endometritis in dairy cattle.
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Doenças dos Bovinos , Endométrio , Infecções por Escherichia coli , Escherichia coli , Animais , Feminino , Bovinos , Infecções por Escherichia coli/veterinária , Infecções por Escherichia coli/imunologia , Endométrio/metabolismo , Doenças dos Bovinos/microbiologia , Doenças dos Bovinos/metabolismo , Doenças dos Bovinos/imunologia , Lipoproteínas/metabolismo , Endometrite/veterinária , Endometrite/microbiologia , Endometrite/metabolismo , Endometrite/imunologia , Citocinas/metabolismo , Citocinas/genética , Tolerância ImunológicaRESUMO
Liver ischemia-reperfusion injury (LIRI) is a pathological process involving multiple injury factors and cell types, with different stages. Currently, protective drugs targeting a single condition are limited in efficacy, and interventions on immune cells will also be accompanied by a series of side effects. In the current bottleneck research stage, the multi-target and obvious clinical efficacy of Chinese medicine (CM) is expected to become a breakthrough point in the research and development of new drugs. In this review, we summarize the roles of reactive oxygen species (ROS) and reactive nitrogen species (RNS) in various stages of hepatic ischemia-reperfusion and on various types of cells. Combined with the current research progress in reducing ROS/RNS with CM, new therapies and mechanisms for the treatment of hepatic ischemia-reperfusion are discussed.
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BACKGROUND: Caenorhabditis elegans (C. elegans) has been recognized for being a useful model organism in small-molecule drug screens and drug efficacy investigation. However, there remain bottlenecks in evaluating such processes as drug uptake and distribution due to a lack of appropriate chemical tools. PURPOSE: This study aims to prepare fluorescence-labeled leonurine as an example to monitor drug uptake and distribution of small molecule in C. elegans and living cells. METHODS: FITC-conjugated leonurine (leonurine-P) was synthesized and characterized by LC/MS, NMR, UV absorption and fluorescence intensity. Leonurine-P was used to stain C. elegans and various mammalian cell lines. Different concentrations of leonurine were tested in conjunction with a competing parent molecule to determine whether leonurine-P and leonurine shared the same biological targets. Drug distribution was analyzed by imaging. Fluorometry in microplates and flow cytometry were performed for quantitative measurements of drug uptake. RESULTS: The UV absorption peak of leonurine-P was 490â¼495 nm and emission peak was 520 nm. Leonurine-P specifically bound to endogenous protein targets in C. elegans and mammalian cells, which was competitively blocked by leonurine. The highest enrichment levels of leonurine-P were observed around 72 h following exposure in C. elegans. Leonurine-P can be used in a variety of cells to observe drug distribution dynamics. Flow cytometry of stained cells can be facilely carried out to quantitatively detect probe signals. CONCLUSIONS: The strategy of fluorescein-labeled drugs reported herein allows quantification of drug enrichment and visualization of drug distribution, thus illustrates a convenient approach to study phytodrugs in pharmacological contexts.
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Caenorhabditis elegans , Ácido Gálico , Animais , Ácido Gálico/análogos & derivados , Ácido Gálico/farmacocinética , Ácido Gálico/metabolismo , Humanos , Fluoresceína-5-Isotiocianato/análogos & derivados , Citometria de Fluxo , Fluorescência , Corantes FluorescentesRESUMO
The insight of the activity phase and reaction mechanism is vital for developing high-performance ammonia synthesis electrocatalysts. In this study, the origin of the electronic-dependent activity for the model Cu2O catalyst toward ammonia electrosynthesis with nitrate was probed. The modulation of the electronic state and oxygen vacancy content of Cu2O was realized by doping with halogen elements (Cl, Br, I). The electrocatalytic experiments showed that the activity of the ammonia production depends strongly on the electronic states in Cu2O. With increased electronic state defects in Cu2O, the ammonia synthesis performance increased first and then decreased. The Cu2O/Br with electronic defects in the middle showed the highest ammonia yield of 11.4 g h-1 g-1 at -1.0 V (vs. RHE), indicating that the pattern of change in optimal ammonia activity is consistent with the phenomenon of volcano curves in reaction chemistry. This work highlights a promising route for designing NO3-RR to NH3 catalysts.
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This study aimed to explore the effects of neonatal vitamin A (VA) supplementation on testis development and spermatogenesis. A total of 32 newborn lambs were intramuscularly injected with corn oil (control group) or corn oil + 2500 IU/kg BW VA (VA group). They were slaughtered and sampled at 3 weeks and 8 months of age to analyze spermatogenesis, cell proliferation, hormone secretion, antioxidant status of the testis, and adult sheep sperm parameters. Compared with the control group, the expression of spermatogonial differentiation-related genes in VA group was up-regulated (P < 0.05). Testis weight, seminiferous tubule diameter, number of spermatogonium and spermatocyte, and sperm density increased significantly in VA group at 8 months of age (P < 0.05). Neonatal VA injection upregulated the expression of the cell proliferation marker PCNA and cell cycle-related genes in the testis (P < 0.05). VA increased the concentrations of testosterone (T), luteinizing hormone (LH), and follicle-stimulating hormone (FSH) in the serum and upregulated steroidogenesis-related genes in the testis (P < 0.05). The antioxidant levels in the VA group were maintained at high levels. The total antioxidant capacity (T-AOC), antioxidant enzyme content and antioxidant-related genes were increased in the testis (P < 0.05). Furthermore, neonatal VA injection activated retinoic acid (RA) signaling to maintain the blood-testosterone barrier (BTB) in the testis of 3-week-old sheep. AMP-activated protein kinase (AMPK) and protein kinase B (AKT) signaling were also modulated in the sheep testis (P < 0.05). Taken together, VA supplementation in newborn rams promotes testis development and spermatogenesis to improve fertility.
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Rapid advancements in flexible electronics technology propel soft tactile sensing devices toward high-level biointegration, even attaining tactile perception capabilities surpassing human skin. However, the inherent mechanical mismatch resulting from deficient biomimetic mechanical properties of sensing materials poses a challenge to the application of wearable tactile sensing devices in human-machine interaction. Inspired by the innate biphasic structure of human subcutaneous tissue, this study discloses a skin-compliant wearable iontronic triboelectric gel via phase separation induced by competitive hydrogen bonding. Solvent-nonsolvent interactions are used to construct competitive hydrogen bonding systems to trigger phase separation, and the resulting soft-hard alternating phase-locked structure confers the iontronic triboelectric gel with Young's modulus (6.8-281.9 kPa) and high tensile properties (880%) compatible with human skin. The abundance of reactive hydroxyl groups gives the gel excellent tribopositive and self-adhesive properties (peel strength > 70 N m-1). The self-powered tactile sensing skin based on this gel maintains favorable interface and mechanical stability with the working object, which greatly ensures the high fidelity and reliability of soft tactile sensing signals. This strategy, enabling skin-compliant design and broad dynamic tunability of the mechanical properties of sensing materials, presents a universal platform for broad applications from soft robots to wearable electronics.
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Guanidinoacetic acid (GAA) is a naturally occurring amino acid derivative that plays a critical role in energy metabolism. In recent years, a growing body of evidence has emerged supporting the importance of GAA in metabolic dysfunction. Hence, we aimed to investigate the effects of GAA on hepatic and adipose tissue metabolism, as well as systemic inflammatory responses in obese middle-aged mice models and attempted to explore the underlying mechanism. We found that dietary supplementation of GAA inhibited inguinal white adipose tissue (iWAT) hypertrophy in high-fat diet (HFD)-fed mice. In addition, GAA supplementation observably decreased the levels of some systemic inflammatory factors, including IL-4, TNF-α, IL-1ß, and IL-6. Intriguingly, GAA supplementation ameliorated hepatic steatosis and lipid deposition in HFD-fed mice, which was revealed by decreased levels of TG, TC, LDL-C, PPARγ, SREBP-1c, FASN, ACC, FABP1, and APOB and increased levels of HDL-C in the liver. Moreover, GAA supplementation increased the expression of browning markers and mitochondrial-related genes in the iWAT. Further investigation showed that dietary GAA promoted the browning of the iWAT via activating the AMPK/Sirt1 signaling pathway and might be associated with futile creatine cycling in obese mice. These results indicate that GAA has the potential to be used as an effective ingredient in dietary interventions and thus may play an important role in ameliorating and preventing HFD-induced obesity and related metabolic diseases.