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1.
ACS Nano ; 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39011629

RESUMO

The chirality of materials directly influences their transport and biological effects in physiological conditions. However, the impact of chiral materials on cellular metabolic reprogramming remains incompletely elucidated. In this study, we have synthesized chiral gold particles through a light-driven particle growth approach and demonstrated that d-Au particles exhibited superior macrophage activation ability compared to l-Au particles. An inflammatory creatine-phosphocreatine shunt was induced following d-Au stimulation. This shunt, facilitated by the upregulated expression of creatine kinase muscle-type (CKM), also resulted in a reduction in cytosolic levels of creatine. Pharmacological inhibition and genetic ablation of CKM further suppressed the secretion of pro-inflammatory cytokines, without compromising mitochondrial respiration. Moreover, the activation of macrophages induced by d-Au was mediated through the activation of the NF-κB and NLRP3 inflammasome pathways. Inhibition of CKM expression not only decreased the secretion of CXCL2 but also attenuated IL-1ß by suppressing the NLRP3 inflammasome pathways. Our investigation into the metabolic reprogramming mechanism of chiral materials on macrophage activation is pivotal for the application of chiral-based anticancer therapies.

2.
Nat Commun ; 15(1): 5567, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956087

RESUMO

Diabetes involves the death or dysfunction of pancreatic ß-cells. Analysis of bulk sequencing from human samples and studies using in vitro and in vivo models suggest that endoplasmic reticulum and inflammatory signaling play an important role in diabetes progression. To better characterize cell type-specific stress response, we perform multiplexed single-cell RNA sequencing to define the transcriptional signature of primary human islet cells exposed to endoplasmic reticulum and inflammatory stress. Through comprehensive pair-wise analysis of stress responses across pancreatic endocrine and exocrine cell types, we define changes in gene expression for each cell type under different diabetes-associated stressors. We find that ß-, α-, and ductal cells have the greatest transcriptional response. We utilize stem cell-derived islets to study islet health through the candidate gene CIB1, which was upregulated under stress in primary human islets. Our findings provide insights into cell type-specific responses to diabetes-associated stress and establish a resource to identify targets for diabetes therapeutics.


Assuntos
Estresse do Retículo Endoplasmático , Células Secretoras de Insulina , Ilhotas Pancreáticas , Humanos , Estresse do Retículo Endoplasmático/genética , Ilhotas Pancreáticas/metabolismo , Células Secretoras de Insulina/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas de Ligação ao Cálcio/genética , Análise de Célula Única , Células Secretoras de Glucagon/metabolismo , Análise de Sequência de RNA , Transcriptoma , Estresse Fisiológico
3.
Chin Neurosurg J ; 10(1): 12, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594757

RESUMO

BACKGROUND: Patients with disorders of consciousness (DoC) exhibit varied revival outcomes based on different etiologies and diagnoses, the mechanisms of which remain largely unknown. The fluctuating clinical presentations in DoC pose challenges in accurately assessing consciousness levels and prognoses, often leading to misdiagnoses. There is an urgent need for a deeper understanding of the physiological changes in DoC and the development of objective diagnostic and prognostic biomarkers to improve treatment guidance. METHODS: To explore biomarkers and understand the biological processes, we conducted a comprehensive untargeted metabolomic analysis on serum samples from 48 patients with DoC. Patients were categorized based on etiology (TBI vs. non-TBI), CRS-R scores, and prognosis. Advanced analytical techniques, including PCA and OPLS-DA models, were employed to identify differential metabolites. RESULTS: Our analysis revealed a distinct separation in metabolomic profiles among the different groups. The primary differential metabolites distinguishing patients with varying etiologies were predominantly phospholipids, with a notable decrease in glycerophospholipids observed in the TBI group. Patients with higher CRS-R scores exhibited a pattern of impaired carbohydrate metabolism coupled with enhanced lipid metabolism. Notably, serum concentrations of both LysoPE and PE were reduced in patients with improved outcomes, suggesting their potential as prognostic biomarkers. CONCLUSIONS: Our study underscores the critical role of phospholipid metabolism in the brain's metabolic alterations in patients with DoC. It identifies key biomarkers for diagnosis and prognosis, offering insights that could lead to novel therapeutic targets. These findings highlight the value of metabolomic profiling in understanding and potentially treating DoC.

4.
Metabolomics ; 20(1): 18, 2024 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-38281200

RESUMO

OBJECTIVE: This study aimed to reveal the urinary and serum metabolic pattern of endometrial cancer (EC) and establish diagnostic models to identify EC from controls, high-risk from low-risk EC, and type II from type I EC. METHOD: This study included 146 EC patients (comprising 79 low-risk and 67 high-risk patients, including 124 type I and 22 type II) and 59 controls. The serum and urine samples were analyzed using ultraperformance liquid chromatography mass spectrometry. Analysis was used to elucidate the distinct metabolites and altered metabolic pathways. Receiver operating characteristic (ROC) analyses were employed to discover and validate the potential biomarker models. RESULTS: Serum and urine metabolomes displayed significant differences between EC and controls, with metabolites related to amino acid and nicotinamide metabolisms. The serum and urine panels distinguished these two groups with Area Under the Curve (AUC) of 0.821 and 0.902, respectively. The panel consisting of serum and urine metabolites demonstrated the best predictive ability (AUC = 0.953 and 0.976 in discovering and validation group). In comparing high-risk and low risk EC, differential metabolites were enriched in purine and glutamine metabolism. The AUC values for serum and urine panels were 0.818, and 0.843, respectively. The combined panel exhibited better predictive accuracy (0.881 in discovering group and 0.936 in external validation). In the comparison between type I and type II group, altered folic acid metabolism was identified. The serum, urine and combined panels discriminated these two groups with the AUC of 0.829, 0.913 and 0.922, respectively. CONCLUSION: The combined urine and serum metabolome effectively revealed the metabolic patterns in EC patients, offering valuable diagnostic models for EC diagnosis and classification.


Assuntos
Neoplasias do Endométrio , Metabolômica , Feminino , Humanos , Metabolômica/métodos , Espectrometria de Massa com Cromatografia Líquida , Metaboloma , Neoplasias do Endométrio/diagnóstico , Biomarcadores/urina
5.
Cell Mol Gastroenterol Hepatol ; 17(5): 801-820, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38280549

RESUMO

BACKGROUND & AIMS: Restoring hepatic and peripheral insulin sensitivity is critical to prevent or reverse metabolic syndrome and type 2 diabetes. Glucose homeostasis comprises in part the complex regulation of hepatic glucose production and insulin-mediated glucose uptake and oxidation in peripheral tissues. We previously identified hepatocyte arginase 2 (Arg2) as an inducible ureahydrolase that improves glucose homeostasis and enhances glucose oxidation in multiple obese, insulin-resistant models. We therefore examined structure-function determinants through which hepatocyte Arg2 governs systemic insulin action and glucose oxidation. METHODS: To do this, we generated mice expressing wild-type murine Arg2, enzymatically inactive Arg2 (Arg2H160F) and Arg2 lacking its putative mitochondrial targeting sequence (Arg2Δ1-22). We expressed these hepatocyte-specific constructs in obese, diabetic (db/db) mice and performed genetic complementation analyses in hepatocyte-specific Arg2-deficent (Arg2LKO) mice. RESULTS: We show that Arg2 attenuates hepatic steatosis, independent of mitochondrial localization or ureahydrolase activity, and that enzymatic arginase activity is dispensable for Arg2 to augment total body energy expenditure. In contrast, mitochondrial localization and ureahydrolase activity were required for Arg2-mediated reductions in fasting glucose and insulin resistance indices. Mechanistically, Arg2Δ1-22 and Arg2H160F failed to suppress glucose appearance during hyperinsulinemic-euglycemic clamping. Quantification of heavy-isotope-labeled glucose oxidation further revealed that mistargeting or ablating Arg2 enzymatic function abrogates Arg2-induced peripheral glucose oxidation. CONCLUSION: We conclude that the metabolic effects of Arg2 extend beyond its enzymatic activity, yet hepatocyte mitochondrial ureahydrolysis drives hepatic and peripheral oxidative metabolism. The data define a structure-based mechanism mediating hepatocyte Arg2 function and nominate hepatocyte mitochondrial ureahydrolysis as a key determinant of glucose oxidative capacity in mammals.


Assuntos
Arginase , Diabetes Mellitus Tipo 2 , Camundongos , Animais , Arginase/genética , Arginase/metabolismo , Glucose , Hepatócitos/metabolismo , Obesidade/metabolismo , Insulina , Mamíferos/metabolismo
6.
Proteomics Clin Appl ; 18(1): e2200107, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37697649

RESUMO

BACKGROUND: Chronic subdural hematoma (CSDH) is one of the most common neurosurgical diseases with atypical manifestations. The aim of this study was to utilize urine metabolomics to explore potential biomarkers for the diagnosis and prognosis of CSDH. METHODS: Seventy-seven healthy controls and ninety-two patients with CSDH were enrolled in our study. In total, 261 urine samples divided into the discovery group and validation group were analyzed by LC-MS. The statistical analysis and functional annotation were applied to discover potential biomarker panels and altered metabolic pathways. RESULTS: A total of 53 differential metabolites were identified in this study. And the urinary metabolic profiles showed apparent separation between patients and controls. Further functional annotation showed that the differential metabolites were associated with lipid metabolism, fatty acid metabolism, amino acid metabolism, biotin metabolism, steroid hormone biosynthesis, and pentose and glucuronate interconversions. Moreover, one panel of Capryloylglycine, cis-5-Octenoic acid, Ethisterone, and 5,6-DiHETE showed good predictive performance in the diagnosis of CSDH, with an AUC of 0.89 in discovery group and an AUC of 0.822 in validation group. Another five metabolites (Trilobinol, 3'-Hydroxyropivacaine, Ethisterone, Arginyl-Proline, 5-alpha-Dihydrotestosterone glucuronide) showed the levels of them returned to a healthy state after surgery, showing good possibility to monitor the recovery of CSDH patients. CONCLUSION AND CLINICAL RELEVANCE: The findings of the study revealed urine metabolomic differences between CSDH and controls. The potentially diagnostic and prognostic biomarker panels of urine metabolites were established, and functional analysis demonstrated deeper metabolic disorders of CSDH, which might conduce to improve early diagnose of CSDH clinically.


Assuntos
Hematoma Subdural Crônico , Lomustina/análogos & derivados , Humanos , Hematoma Subdural Crônico/cirurgia , Cromatografia Líquida , Etisterona , Espectrometria de Massa com Cromatografia Líquida , Espectrometria de Massas em Tandem , Biomarcadores , Metabolômica
7.
Adv Mater ; 36(6): e2309526, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37983740

RESUMO

Molecular copper catalysts have emerged as promising candidates for the electrochemical reduction of CO2 . Notable features of such systems include the ability of Cu to generate C2+  products and the well-defined active sites that allow for targeted structural tuning. However, the frequently observed in situ formation of Cu nanoclusters has undermined the advantages of the molecular frameworks. It is therefore desirable to develop Cu-based catalysts that retain their molecular structures during electrolysis. In this context, a heterogenized binuclear hydroxo-bridged phenanthroline Cu(II) compound with a short Cu···Cu distance is reported as a simple yet efficient catalyst for electrogeneration of ethylene and other C2 products. In an aqueous electrolyte, the catalyst demonstrates remarkable performance, with excellent Faradaic efficiency for C2 products (62%) and minimal H2 evolution (8%). Furthermore, it exhibits high stability, manifested by no observable degradation during 15 h of continuous electrolysis. The preservation of the atomic distribution of the active sites throughout electrolysis is substantiated through comprehensive characterizations, including X-ray photoelectron and absorption spectroscopy, scanning and transmission electron microscopy, UV-vis spectroscopy, as well as control experiments. These findings establish a solid foundation for further investigations into targeted structural tuning, opening new avenues for enhancing the catalytic performance of Cu-based molecular electrocatalysts.

8.
ACS Nano ; 17(21): 21518-21530, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37897737

RESUMO

Neuromorphic computing based on memristors capable of in-memory computing is promising to break the energy and efficiency bottleneck of well-known von Neumann architectures. However, unstable and nonlinear conductance updates compromise the recognition accuracy and block the integration of neural network hardware. To this end, we present a highly stable memristor with self-assembled vertically aligned nanocomposite (VAN) SrTiO3:MgO films that achieve excellent resistive switching with low set/reset voltage variability (4.7%/-5.6%) and highly linear conductivity variation (nonlinearity = 0.34) by spatially limiting the conductive channels at the vertical interfaces. Various synaptic behaviors are simulated by continuously modulating the conductance. Especially, convolutional image processing using diverse crossbar kernels is demonstrated, and the artificial neural network achieves an overwhelming recognition accuracy of up to 97.50% for handwritten digits. Even under the perturbation of Poisson noise (λ = 10), 6% Salt and Pepper noise, and 5% Gaussian noise, the high recognition accuracies are retained at 95.43%, 94.56%, and 95.97%, respectively. Importantly, the logic memory function is proven experimentally based on the nonvolatile properties. This work provides a material system and design idea to achieve high-performance neuromorphic computing and logic operation.

9.
Curr Mol Med ; 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37817528

RESUMO

OBJECTIVE: To investigate the metabolomic differences between Traumatic brain injury (TBI) disorder of consciousness (DOC) patients and non-traumatic brain injury (NTBI) DOC patients by using cerebrospinal fluid (CSF), serum and urine samples beneficial to understand the pathological mechanism differences between the two etiologies, provide potential clues for the subsequent treatment and prognosis, and investigate the metabolome differences and similarities between TBI and NTBI among three different body fluids. METHODS: In total, 24 TBI DOC subjects and 29 NTBI DOC subjects were enrolled. CSF, serum and urine samples from TBI DOC and NTBI DOC patients were collected and analyzed by performing UPLC-MS. The statistical methods and pathway analyses were applied to discover potential biomarkers and altered metabolic functions. RESULTS: When comparing TBI DOC and NTBI DOC, 36, 31 and 52 differential metabolites were obtained in CSF, serum and urine, respectively. The functional analysis of differential metabolites obtained in CSF, serum and urine were all related to amino acid metabolism. Except for amino acid metabolism, metabolic biomarkers in CSF, serum and urine mainly focus on central function, cognitive function, necrosis and apoptosis and neurological function, respectively. In CSF, the highest AUC was 0.864 (Isoproturon) and 0.816 (Proline betaine). Then, the AUC of NFurfurylformamide in serum was 0.941, while the AUC of Dihydronepetalactone and Doxepin N-oxide glucuronide were 1.0 in urine. CONCLUSION: CSF, serum and urine metabolomic analyses could differentiate TBI DOC from NTBI DOC and functional analyses showed a metabolic change difference between TBI DOC and NTBI DOC.

10.
Mater Horiz ; 10(10): 4521-4531, 2023 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-37555245

RESUMO

By mimicking the behavior of the human brain, artificial neural systems offer the possibility to further improve computing efficiency and solve the von Neumann bottleneck. In particular, neural systems with perceptual capability expand the application field and lay a good foundation for the construction of perceptual storage and computational systems. However, research on neurons with perceptual functions is still relatively scarce, with most works focusing on optoelectronic synapses. The neuron is important for neuromorphic computing systems because neurons output excitatory or inhibitory stimuli to regulate the weight of synapses. Therefore, the construction of sensory neurons is crucial to expand the application range of brain-like neural computing. Here, an artificial sensory neuron is proposed, which is constructed using a photosensitive bipolar threshold switching memristor based on NdNiO3 (NNO) nanocrystals. These metallic phase nanocrystals can not only enhance the local electric field, but also act as a reservoir for defects (VoS) to guide the growth of conductive filaments and stabilize the performance of the device. They present stable bipolar threshold switching behavior with a low 120 nW set power, and the operating voltages decreased in light due to photocarrier action. A leaky integrate firing (LIF) neuron has been realized, which achieved key biological neuron functions, such as all-or-nothing spiking, threshold-driven firing, refractory period, and spiking frequency modulation. The LIF neurons receiving optical inputs have the properties of an artificial sensory neuron. It could regulate the spiking output frequency at different light densities, which could be used for a ship approaching a port. This work provides a promising hardware implementation towards constructing high-performance artificial intelligence to assist ships at night in a sensory system.


Assuntos
Inteligência Artificial , Nanopartículas , Humanos , Redes Neurais de Computação , Computadores , Células Receptoras Sensoriais
11.
Brain Behav ; 13(8): e3070, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37421239

RESUMO

INTRODUCTION: Medical management of disorders of consciousness (DoC) is a growing issue imposing a major burden on families and societies. Recovery rates vary widely among patients with DoC, and recovery predictions strongly influence decisions on medical care. However, the specific mechanisms underlying different etiologies, consciousness levels, and prognoses are still unclear. METHODS: We analyzed the comprehensive cerebrospinal fluid (CSF) metabolome through liquid chromatography-mass spectrometry. Metabolomic analyses were used to identify the metabolic differences between patients with different etiologies, diagnoses, and prognoses. RESULTS: We found that the CSF levels of multiple acylcarnitines were lower in patients with traumatic DoC, suggesting mitochondrial function preservation in the CNS, which might contribute to the better consciousness outcomes of these patients. Metabolites related to glutamate and GABA metabolism were altered and showed a good ability to distinguish the patients in the minimally conscious state and the vegetative state. Moreover, we identified 8 phospholipids as potential biomarkers to predict the recovery of consciousness. CONCLUSIONS: Our findings shed light on the differences in physiological activities underlying DoC with different etiologies and identified some potential biomarkers used for DoC diagnosis and prognosis.


Assuntos
Transtornos da Consciência , Estado de Consciência , Humanos , Estado de Consciência/fisiologia , Prognóstico , Metabolômica , Espectrometria de Massas , Estado Vegetativo Persistente/complicações
12.
Mol Cell Proteomics ; 22(8): 100603, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37348606

RESUMO

Liquid biopsy is a noninvasive technique that can provide valuable information for disease characterization by using biofluids as a source of biomarkers. Proteins found in biofluids can offer a wealth of information for understanding pathological processes. In this study, we used early-stage clear cell renal cell carcinoma (ccRCC) as a model to explore the proteomic relationships among tissue, plasma, and urine. We analyzed samples of tumor tissue, plasma, and urine from a cohort of 27 ccRCC patients with T1-2 stage and 27 matched healthy controls, using liquid chromatography-mass spectrometry (LC-MS) for proteomic analysis. We integrated the differential proteins found in the three types of samples to explore ccRCC-associated molecular changes. Our results showed that both plasma and urine proteomes could reflect functional changes in tumor tissue. In plasma, cytoskeletal proteins and metabolic enzymes were differentially expressed, while in urine, adhesion molecules and defense proteins showed differential levels. The differential proteins found in plasma and urine both reflect the binding and catalytic activity of tumor tissue. Additionally, proteins only changed in biofluids could reflect body immune response changes, with plasma proteins involved in actin cytoskeleton and oxidative stress, and urine proteins involved in granulocyte adhesion and leukocyte extravasation signaling. Plasma and urine proteins could effectively distinguish RCC from control, with good performances (plasma/urine: 92.6%/92.6% specificity, 96.3%/92.6% sensitivity, and an area under the curve of 0.981/0.97). In conclusion, biofluids could not only reflect functional changes in tumor tissue but also reflect changes in the body's immune response. These findings will benefit the understanding of body biomarkers in tumors and the discovery of potential disease biomarkers.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , Carcinoma de Células Renais/metabolismo , Neoplasias Renais/metabolismo , Proteômica/métodos , Biomarcadores Tumorais/metabolismo , Biópsia Líquida
13.
Int J Mol Sci ; 24(2)2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36675248

RESUMO

The essential oil of German chamomile (Matricaria recutita L.) is widely used in food, cosmetics, and the pharmaceutical industry. α-Bisabolol is the main active substance in German chamomile. Farnesyl diphosphate synthase (FPS) and α-bisabolol synthase (BBS) are key enzymes related to the α-bisabolol biosynthesis pathway. However, little is known about the α-bisabolol biosynthesis pathway in German chamomile, especially the transcription factors (TFs) related to the regulation of α-bisabolol synthesis. In this study, we identified MrFPS and MrBBS and investigated their functions by prokaryotic expression and expression in hairy root cells of German chamomile. The results suggest that MrFPS is the key enzyme in the production of sesquiterpenoids, and MrBBS catalyzes the reaction that produces α-bisabolol. Subcellular localization analysis showed that both MrFPS and MrBBS proteins were located in the cytosol. The expression levels of both MrFPS and MrBBS were highest in the extension period of ray florets. Furthermore, we cloned and analyzed the promoters of MrFPS and MrBBS. A large number of cis-acting elements related to light responsiveness, hormone response elements, and cis-regulatory elements that serve as putative binding sites for specific TFs in response to various biotic and abiotic stresses were identified. We identified and studied TFs related to MrFPS and MrBBS, including WRKY, AP2, and MYB. Our findings reveal the biosynthesis and regulation of α-bisabolol in German chamomile and provide novel insights for the production of α-bisabolol using synthetic biology methods.


Assuntos
Matricaria , Óleos Voláteis , Sesquiterpenos , Geraniltranstransferase/genética , Matricaria/química , Fatores de Transcrição/genética , Óleos Voláteis/química , Sesquiterpenos/química
14.
J Biol Chem ; 299(2): 102835, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36581203

RESUMO

Tetraspanins are transmembrane signaling and proinflammatory proteins. Prior work demonstrates that the tetraspanin, CD53/TSPAN25/MOX44, mediates B-cell development and lymphocyte migration to lymph nodes and is implicated in various inflammatory diseases. However, CD53 is also expressed in highly metabolic tissues, including adipose and liver; yet its function outside the lymphoid compartment is not defined. Here, we show that CD53 demarcates the nutritional and inflammatory status of hepatocytes. High-fat exposure and inflammatory stimuli induced CD53 in vivo in liver and isolated primary hepatocytes. In contrast, restricting hepatocyte glucose flux through hepatocyte glucose transporter 8 deletion or through trehalose treatment blocked CD53 induction in fat- and fructose-exposed contexts. Furthermore, germline CD53 deletion in vivo blocked Western diet-induced dyslipidemia and hepatic inflammatory transcriptomic activation. Surprisingly, metabolic protection in CD53 KO mice was more pronounced in the presence of an inciting inflammatory event. CD53 deletion attenuated tumor necrosis factor alpha-induced and fatty acid + lipopolysaccharide-induced cytokine gene expression and hepatocyte triglyceride accumulation in isolated murine hepatocytes. In vivo, CD53 deletion in nonalcoholic steatohepatitis diet-fed mice blocked peripheral adipose accumulation and adipose inflammation, insulin tolerance, and liver lipid accumulation. We then defined a stabilized and trehalase-resistant trehalose polymer that blocks hepatocyte CD53 expression in basal and over-fed contexts. The data suggest that CD53 integrates inflammatory and metabolic signals in response to hepatocyte nutritional status and that CD53 blockade may provide a means by which to attenuate pathophysiology in diseases that integrate overnutrition and inflammation, such as nonalcoholic steatohepatitis and type 2 diabetes.


Assuntos
Hepatócitos , Hepatopatia Gordurosa não Alcoólica , Tetraspanina 25 , Animais , Camundongos , Dieta Hiperlipídica , Hepatócitos/metabolismo , Inflamação/genética , Inflamação/metabolismo , Fígado/metabolismo , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/metabolismo , Obesidade/metabolismo , Tetraspanina 25/metabolismo , Tetraspaninas/genética , Tetraspaninas/metabolismo , Trealose/metabolismo
16.
Materials (Basel) ; 15(19)2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-36234233

RESUMO

Ag-Zn alloys are identified as highly active and selective electrocatalysts for CO2 reduction reaction (CO2RR), while how the phase composition of the alloy affects the catalytic performances has not been systematically studied yet. In this study, we fabricated a series of Ag-Zn alloy catalysts by magnetron co-sputtering and further explored their activity and selectivity towards CO2 electroreduction in an aqueous KHCO3 electrolyte. The different Ag-Zn alloys involve one or more phases of Ag, AgZn, Ag5Zn8, AgZn3, and Zn. For all the catalysts, CO is the main product, likely due to the weak CO binding energy on the catalyst surface. The Ag5Zn8 and AgZn3 catalysts show a higher CO selectivity than that of pure Zn due to the synergistic effect of Ag and Zn, while the pure Ag catalyst exhibits the highest CO selectivity. Zn alloying improves the catalytic activity and reaction kinetics of CO2RR, and the AgZn3 catalyst shows the highest apparent electrocatalytic activity. This work found that the activity and selectivity of CO2RR are highly dependent on the element concentrations and phase compositions, which is inspiring to explore Ag-Zn alloy catalysts with promising CO2RR properties.

17.
Blood Cancer Discov ; 3(3): 220-239, 2022 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-35394496

RESUMO

Clonal hematopoiesis (CH) refers to the age-related expansion of specific clones in the blood system, and manifests from somatic mutations acquired in hematopoietic stem cells (HSCs). Most CH variants occur in the gene DNMT3A, but while DNMT3A-mutant CH becomes almost ubiquitous in aging humans, a unifying molecular mechanism to illuminate how DNMT3A-mutant HSCs outcompete their counterparts is lacking. Here, we used interferon gamma (IFNγ) as a model to study the mechanisms by which Dnmt3a mutations increase HSC fitness under hematopoietic stress. We found Dnmt3a-mutant HSCs resist IFNγ-mediated depletion, and IFNγ-signaling is required for clonal expansion of Dnmt3a-mutant HSCs in vivo. Mechanistically, DNA hypomethylation-associated overexpression of Txnip in Dnmt3a-mutant HSCs leads to p53 stabilization and upregulation of p21. This preserves the functional potential of Dnmt3a-mutant HSCs through increased quiescence and resistance to IFNγ-induced apoptosis. These data identify a previously undescribed mechanism to explain increased fitness of DNMT3A-mutant clones under hematopoietic stress. SIGNIFICANCE: DNMT3A mutations are common variants in clonal hematopoiesis, and recurrent events in blood cancers. Yet the mechanisms by which these mutations provide hematopoietic stem cells a competitive advantage as a precursor to malignant transformation remain unclear. Here, we use inflammatory stress to uncover molecular mechanisms leading to this fitness advantage.See related commentary by De Dominici and DeGregori, p. 178. This article is highlighted in the In This Issue feature, p. 171.


Assuntos
DNA (Citosina-5-)-Metiltransferases , Hematopoese , Humanos , Proteínas de Transporte/genética , Hematopoiese Clonal , Células Clonais , DNA (Citosina-5-)-Metiltransferases/genética , Metilases de Modificação do DNA/genética , Hematopoese/genética , Células-Tronco Hematopoéticas
18.
Front Mol Biosci ; 9: 761562, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35252347

RESUMO

Vitiligo is a common acquired skin disorder caused by immune-mediated destruction of epidermal melanocytes. Systemic glucocorticoids (GCs) have been used to prevent the progression of active vitiligo, with 8.2-56.2% of patients insensitive to this therapy. Currently, there is a lack of biomarkers that can accurately predict and evaluate treatment responses. The goal of this study was to identify candidate urinary protein biomarkers to predict the efficacy of GCs treatment in active vitiligo patients and monitor the disease. Fifty-eight non-segmental vitiligo patients were enrolled, and 116 urine samples were collected before and after GCs treatment. Patients were classified into a treatment-effective group (n = 42) and a treatment-resistant group (n = 16). Each group was divided equally into age- and sex-matched experimental and validation groups, and proteomic analyses were performed. Differentially expressed proteins were identified, and Ingenuity Pathway Analysis was conducted for the functional annotation of these proteins. Receiver operating characteristic curves were used to evaluate the diagnostic value. A total of 245 and 341 differentially expressed proteins between the treatment-resistant and treatment-effective groups were found before and after GCs treatment, respectively. Bioinformatic analysis revealed that the urinary proteome reflected the efficacy of GCs in active vitiligo patients. Eighty and fifty-four candidate biomarkers for treatment response prediction and treatment response evaluation were validated, respectively. By ELISA analysis, retinol binding protein-1 and torsin 1A interacting protein 1 were validated to have the potential to predict the efficacy of GCs with AUC value of 1 and 0.875, respectively. Retinol binding protein-1, torsin 1A interacting protein 1 and protein disulfide-isomerase A4 were validated to have the potential to reflect positive treatment effect to GCs treatment in active vitiligo with AUC value of 0.861, 1 and 0.868, respectively. This report is the first to identify urine biomarkers for GCs treatment efficacy prediction in vitiligo patients. These findings might contribute to the application of GCs in treating active vitiligo patients.

19.
Proteomics Clin Appl ; 16(2): e2100007, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34687263

RESUMO

PURPOSE: The healthy human urine sediment proteome and metaproteome are investigated, to shed light on the variations of urine sediment proteins and metaproteins associated with sex and age. EXPERIMENTAL DESIGN: Urine sediment samples are collected from 19 healthy subjects. Protein identification and quantification are performed by liquid chromatography coupled high-resolution mass spectrometry. RESULTS: A total of 2736 human proteins were identified, which were primarily associated with inflammatory response and energy metabolism. For the metaproteome, 65 genera were identified that were primarily involved in translation and carbohydrate metabolic processes. The median biological coefficient variation of the proteome/metaproteome of human urine sediment was 0.5/0.72, similar to the proteome of human urine supernatant. In addition, sex and age were observed to affect the proteome and metaproteome of healthy human urine sediment. CONCLUSION AND CLINICAL RELEVANCE: The healthy human urine sediment were characterized, indicating that urine sediment might represent an alternative resource for disease research in addition to urine supernatant, but the influence of sex and age must be considered in the study design process.


Assuntos
Proteoma , Proteômica , Cromatografia Líquida , Humanos , Espectrometria de Massas , Proteoma/análise
20.
Elife ; 102021 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-34279222

RESUMO

Multiple spaced trials of aversive differential conditioning can produce two independent long-term memories (LTMs) of opposite valence. One is an aversive memory for avoiding the conditioned stimulus (CS+), and the other is a safety memory for approaching the non-conditioned stimulus (CS-). Here, we show that a single trial of aversive differential conditioning yields one merged LTM (mLTM) for avoiding both CS+ and CS-. Such mLTM can be detected after sequential exposures to the shock-paired CS+ and -unpaired CS-, and be retrieved by either CS+ or CS-. The formation of mLTM relies on triggering aversive-reinforcing dopaminergic neurons and subsequent new protein synthesis. Expressing mLTM involves αß Kenyon cells and corresponding approach-directing mushroom body output neurons, in which similar-amplitude long-term depression of responses to CS+ and CS- seems to signal the mLTM. Our results suggest that animals can develop distinct strategies for occasional and repeated threatening experiences.


Assuntos
Drosophila melanogaster/fisiologia , Memória de Longo Prazo/fisiologia , Animais , Encéfalo/patologia , Condicionamento Clássico/fisiologia , Condicionamento Psicológico , Neurônios Dopaminérgicos/metabolismo , Feminino , Memória/fisiologia , Corpos Pedunculados , Neurônios/fisiologia
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