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1.
Small ; 20(25): e2307328, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38196157

RESUMO

In the development of nanomaterial electrodes for improved electrocatalytic activity, much attention is paid to the compositions, lattice, and surface morphologies. In this study, a new concept to enhance electrocatalytic activity is proposed by reducing impedance inside nanomaterial electrodes. Gold nanodendrites (AuNDs) are grown along silver nanowires (AgNWs) on flexible polydimethylsiloxane (PDMS) support. The AuNDs/AgNWs/PDMS electrode affords an oxidative peak current density of 50 mA cm-2 for ethanol electrooxidation, a value ≈20 times higher than those in the literature do. Electrochemical impedance spectroscopy (EIS) demonstrates the significant contribution of the AgNWs to reduce impedance. The peak current densities for ethanol electrooxidation are decreased 7.5-fold when the AgNWs are electrolytically corroded. By in situ surface-enhanced Raman spectroscopy (SERS) and density functional theory (DFT) simulation, it is validated that the ethanol electrooxidation favors the production of acetic acid with undetectable CO, resulting in a more complete oxidation and long-term stability, while the AgNWs corrosion greatly decreases acetic acid production. This novel strategy for fabricating nanomaterial electrodes using AgNWs as a charge transfer conduit may stimulate insights into the design of nanomaterial electrodes.

2.
Opt Lett ; 49(9): 2413-2416, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38691732

RESUMO

A novel, to the best of our knowledge, cross-spectral optical computing imaging experiment has been achieved through a single exposure of a charge-coupled device. The experimental setup integrates single-pixel imaging (SPI) with ghost imaging (GI) through a photoelectric conversion circuit and a synchronous modulation system. The experimental process involves modulation in one wavelength band (in SPI) and demodulation using the GI algorithm in another. Significantly, our approach utilizes optical computing demodulation, a departure from the conventional electronic demodulation in GI (SPI), which involves the convolution between the bucket optical signals and the modulated patterns on the digital micromirror device. A proof-of-concept cross-band imaging experiment from near-infrared to visible light has been carried out. The results highlight the system's ability to capture images at up to 20 frames per second using near-infrared illumination, which are then reconstructed in the visible light spectrum. This success not only validates the feasibility of our approach but also expands the potential applications in the SPI or GI fields, particularly in scenarios where two-dimensional detector arrays are either unavailable or prohibitively expensive in certain electromagnetic spectra such as x-ray and terahertz.

3.
Opt Lett ; 49(15): 4162-4165, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39090884

RESUMO

Based on the x-ray absorption edges of different elements, we simultaneously image and distinguish the composition of three differently shaped components of an object by using energy-resolved x-ray absorption ghost imaging (GI). The initial x-ray beam is spatially modulated by a series of Hadamard matrix masks, and the object is composed of three pieces of Mo, Ag, and Sn foil in the shape of a triangle, square, and circle, respectively. The transmitted x-ray intensity is measured by an energy-resolved single-pixel detector with a spectral resolution better than 0.8 keV. Through correlation of the transmission spectra with the corresponding Hadamard patterns, the spectral image of the sample is reconstructed, with a spatial resolution of 108 µm. Our experiment demonstrates a practical application of spectral ghost imaging, which has important potential for the noninvasive analysis of material composition and distribution in biology, medical science, and many other fields.

4.
Acta Pharmacol Sin ; 45(8): 1673-1685, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38641746

RESUMO

Acute kidney injury (AKI) is defined as sudden loss of renal function characterized by increased serum creatinine levels and reduced urinary output with a duration of 7 days. Ferroptosis, an iron-dependent regulated necrotic pathway, has been implicated in the progression of AKI, while ferrostatin-1 (Fer-1), a selective inhibitor of ferroptosis, inhibited renal damage, oxidative stress and tubular cell death in AKI mouse models. However, the clinical translation of Fer-1 is limited due to its lack of efficacy and metabolic instability. In this study we designed and synthesized four Fer-1 analogs (Cpd-A1, Cpd-B1, Cpd-B2, Cpd-B3) with superior plasma stability, and evaluated their therapeutic potential in the treatment of AKI. Compared with Fer-1, all the four analogs displayed a higher distribution in mouse renal tissue in a pharmacokinetic assay and a more effective ferroptosis inhibition in erastin-treated mouse tubular epithelial cells (mTECs) with Cpd-A1 (N-methyl-substituted-tetrazole-Fer-1 analog) being the most efficacious one. In hypoxia/reoxygenation (H/R)- or LPS-treated mTECs, treatment with Cpd-A1 (0.25 µM) effectively attenuated cell damage, reduced inflammatory responses, and inhibited ferroptosis. In ischemia/reperfusion (I/R)- or cecal ligation and puncture (CLP)-induced AKI mouse models, pre-injection of Cpd-A1 (1.25, 2.5, 5 mg·kg-1·d-1, i.p.) dose-dependently improved kidney function, mitigated renal tubular injury, and abrogated inflammation. We conclude that Cpd-A1 may serve as a promising therapeutic agent for the treatment of AKI.


Assuntos
Injúria Renal Aguda , Ferroptose , Camundongos Endogâmicos C57BL , Fenilenodiaminas , Animais , Ferroptose/efeitos dos fármacos , Injúria Renal Aguda/tratamento farmacológico , Injúria Renal Aguda/metabolismo , Camundongos , Masculino , Fenilenodiaminas/farmacologia , Fenilenodiaminas/uso terapêutico , Cicloexilaminas/farmacologia , Cicloexilaminas/uso terapêutico , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/metabolismo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo
5.
Ecotoxicol Environ Saf ; 273: 116149, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38412632

RESUMO

It is still a serious public health issue that chronic kidney disease of uncertain etiology (CKDu) in Sri Lanka poses challenges in identification, prevention, and treatment. What environmental factors in drinking water cause kidney damage remains unclear. This study aimed to investigate the risks of various environmental factors that may induce CKDu, including water hardness, fluoride (HF), heavy metals (HM), microcystin-LR (MC-LR), and their combined exposure (HFMM). The research focused on comprehensive metabolome analysis, and correlation with transcriptomic and gut microbiota changes. Results revealed that chronic exposure led to kidney damage and pancreatic toxicity in adult zebrafish. Metabolomics profiling showed significant alterations in biochemical processes, with enriched metabolic pathways of oxidative phosphorylation, folate biosynthesis, arachidonic acid metabolism, FoxO signaling pathway, lysosome, pyruvate metabolism, and purine metabolism. The network analysis revealed significant changes in metabolites associated with renal function and diseases, including 20-Hydroxy-LTE4, PS(18:0/22:2(13Z,16Z)), Neuromedin N, 20-Oxo-Leukotriene E4, and phenol sulfate, which are involved in the fatty acyls and glycerophospholipids class. These metabolites were closely associated with the disrupted gut bacteria of g_ZOR0006, g_Pseudomonas, g_Tsukamurella, g_Cetobacterium, g_Flavobacterium, which belonged to dominant phyla of Firmicutes and Proteobacteria, etc., and differentially expressed genes (DEGs) such as egln3, ca2, jun, slc2a1b, and gls2b in zebrafish. Exploratory omics analyses revealed the shared significantly changed pathways in transcriptome and metabolome like calcium signaling and necroptosis, suggesting potential biomarkers for assessing kidney disease.


Assuntos
Água Potável , Insuficiência Renal Crônica , Animais , Água Potável/análise , Peixe-Zebra , Sri Lanka , Insuficiência Renal Crônica/etiologia , Metaboloma
6.
Anal Chem ; 95(4): 2413-2419, 2023 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-36633558

RESUMO

The roadblocks for the planar silver/silver chloride (Ag/AgCl) quasi-reference electrode (qRE) development are the potential stability and long-term reliability as potentiometric sensors. Although there is a significant amount of work on potentiometric screen-printed and inkjet-printed sensors, none of the REs has comparable performance to that of the conventional glass RE and knowledge on reliable planar Ag/AgCl qREs is still limited. Here, a novel fishbone-structured flexible Ag/AgCl qRE (Fishbone-Ag/AgCl qRE) was developed and its stability and long-term reliability were significantly improved. The stability of the Fishbone-Ag/AgCl qRE was comparable to that of a commercial glass Ag/AgCl RE. In a long-term stability test, the Fishbone-Ag/AgCl qRE could continuously and stably operate for more than 4 h. Shelf-life testing revealed a 6 month life span. The conductivity and diameter of the nanowires in the fishbone structure of the Ag/AgCl qRE had important influences on electrochemical properties. The conductivity of the qRE influenced the charge-transfer rate in the electrode so that it affected the potential stability. Thicker diameter and slight chlorination on the surface of the AgNWs resulted in enhanced long-term reliability of the qRE. The capabilities of this new nanostructured material were applied in vivo for noninvasive monitoring of electrocardiogram. The discovery is elementary and substantially informs improved nanostructure RE design for testing and commercial medical device applications.


Assuntos
Nanofios , Prata , Prata/química , Reprodutibilidade dos Testes , Eletrodos , Eletrocardiografia
7.
Acta Pharmacol Sin ; 44(11): 2201-2215, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37433872

RESUMO

Pulmonary arterial hypertension (PH) is a chronic disease induced by a progressive increase in pulmonary vascular resistance and failure of the right heart function. A number of studies show that the development of PH is closely related to the gut microbiota, and lung-gut axis might be a potential therapeutic target in the PH treatment. A. muciniphila has been reported to play a critical role in treating cardiovascular disorders. In this study we evaluated the therapeutic effects of A. muciniphila against hypoxia-induced PH and the underlying mechanisms. Mice were pretreated with A. muciniphila suspension (2 × 108 CFU in 200 µL sterile anaerobic PBS, i.g.) every day for 3 weeks, and then exposed to hypoxia (9% O2) for another 4 weeks to induce PH. We showed that A. muciniphila pretreatment significantly facilitated the restoration of the hemodynamics and structure of the cardiopulmonary system, reversed the pathological progression of hypoxia-induced PH. Moreover, A. muciniphila pretreatment significantly modulated the gut microbiota in hypoxia-induced PH mice. miRNA sequencing analysis reveals that miR-208a-3p, a commensal gut bacteria-regulated miRNA, was markedly downregulated in lung tissues exposed to hypoxia, which was restored by A. muciniphila pretreatment. We showed that transfection with miR-208a-3p mimic reversed hypoxia-induced abnormal proliferation of human pulmonary artery smooth muscle cells (hPASMCs) via regulating the cell cycle, whereas knockdown of miR-208a-3p abolished the beneficial effects of A. muciniphila pretreatment in hypoxia-induced PH mice. We demonstrated that miR-208a-3p bound to the 3'-untranslated region of NOVA1 mRNA; the expression of NOVA1 was upregulated in lung tissues exposed to hypoxia, which was reversed by A. muciniphila pretreatment. Furthermore, silencing of NOVA1 reversed hypoxia-induced abnormal proliferation of hPASMCs through cell cycle modulation. Our results demonstrate that A. muciniphila could modulate PH through the miR-208a-3p/NOVA1 axis, providing a new theoretical basis for PH treatment.


Assuntos
Hipertensão Pulmonar , MicroRNAs , Hipertensão Arterial Pulmonar , Humanos , Camundongos , Animais , Hipertensão Arterial Pulmonar/genética , Hipertensão Arterial Pulmonar/metabolismo , Hipertensão Arterial Pulmonar/patologia , Hipertensão Pulmonar/tratamento farmacológico , Hipertensão Pulmonar/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Pulmão/patologia , Artéria Pulmonar/metabolismo , Hipóxia/metabolismo , Miócitos de Músculo Liso/metabolismo , Proteínas de Ligação a RNA/metabolismo , Proliferação de Células/fisiologia , Antígeno Neuro-Oncológico Ventral
8.
J Clin Lab Anal ; 37(5): e24845, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36861291

RESUMO

BACKGROUND: Rheumatoid arthritis (RA) is a persistent and systemic autoimmunity disease. The abnormal differentiation of Treg cells is important in pathogenesis. Despite previous studies showed that microRNAs (miRNAs, miR) are pivotal modulators of Treg cells, the effect of miRNAs on Treg cell differentiation and function is not clear. Our study wants to reveal the relationship of miR-143-3p with the differentiative ability and biofunction of Treg cells during the development of RA. METHODS: The Expressing level of miR-143-3p and cell factor generation in peripheral blood (PB) of RA sufferers were identified by ELISA or RT-qPCR. The roles of miR-143-3p in Treg cell differentiation were studied via ShRNA/lentivirus transfection. Male DBA/1 J mice were separated into control, model, control mimics, and miR-143-3p mimics groups to analyze the anti-arthritis efficacy, the differentiative ability of Treg cells, and the expression level of miR-143-3p. RESULTS: Our team discovered that the Expressing level of miR-143-3p was related to RA disease activities in a negative manner, and remarkably related to antiinflammation cell factor IL-10. In vitro, the expression of miR-143-3p in the CD4+ T cells upregulated the percentage of CD4+ CD25+ Fxop3+ cells (Tregs) and forkhead box protein 3 (Foxp3) mRNA expression. Evidently, miR-143-3p mimic intervention considerably upregulated the content of Treg cells in vivo, validly avoided CIA progression, and remarkably suppressed the inflammatory events of joints in mice. CONCLUSION: Our findings indicated that miR-143-3p could ameliorate CIA through polarizing naive CD4+ T cells into Treg cells, which may be a novel strategy to treat autoimmune diseases such as RA.


Assuntos
Artrite Experimental , Artrite Reumatoide , MicroRNAs , Masculino , Camundongos , Animais , Linfócitos T Reguladores , Artrite Experimental/genética , Artrite Experimental/terapia , Camundongos Endogâmicos DBA , MicroRNAs/metabolismo
9.
Pharm Biol ; 61(1): 459-472, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36794740

RESUMO

CONTEXT: Rheumatoid arthritis (RA) is an autoimmune disease with aberrant Th17 cell differentiation. Panax notoginseng (Burk.) F. H. Chen (Araliaceae) saponins (PNS) have an anti-inflammatory effect and can suppress Th17 cell differentiation. OBJECTIVE: To investigate mechanisms of PNS on Th17 cell differentiation in RA, and the role of pyruvate kinase M2 (PKM2). MATERIALS AND METHODS: Naive CD4+T cells were treated with IL-6, IL-23 and TGF-ß to induce Th17 cell differentiation. Apart from the Control group, other cells were treated with PNS (5, 10, 20 µg/mL). After the treatment, Th17 cell differentiation, PKM2 expression, and STAT3 phosphorylation were measured via flow cytometry, western blots, or immunofluorescence. PKM2-specific allosteric activator (Tepp-46, 50, 100, 150 µM) and inhibitor (SAICAR, 2, 4, 8 µM) were used to verify the mechanisms. A CIA mouse model was established and divided into control, model, and PNS (100 mg/kg) groups to assess an anti-arthritis effect, Th17 cell differentiation, and PKM2/STAT3 expression. RESULTS: PKM2 expression, dimerization, and nuclear accumulation were upregulated upon Th17 cell differentiation. PNS inhibited the Th17 cells, RORγt expression, IL-17A levels, PKM2 dimerization, and nuclear accumulation and Y705-STAT3 phosphorylation in Th17 cells. Using Tepp-46 (100 µM) and SAICAR (4 µM), we demonstrated that PNS (10 µg/mL) inhibited STAT3 phosphorylation and Th17 cell differentiation by suppressing nuclear PKM2 accumulation. In CIA mice, PNS attenuated CIA symptoms, reduced the number of splenic Th17 cells and nuclear PKM2/STAT3 signaling. DISCUSSION AND CONCLUSIONS: PNS inhibited Th17 cell differentiation through the inhibition of nuclear PKM2-mediated STAT3 phosphorylation. PNS may be useful for treating RA.


Assuntos
Panax notoginseng , Saponinas , Camundongos , Animais , Saponinas/farmacologia , Células Th17 , Fosforilação , Diferenciação Celular
10.
Zhongguo Zhong Yao Za Zhi ; 48(17): 4711-4721, 2023 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-37802810

RESUMO

This study aimed to investigate the protective effect and underlying mechanism of Mailuo Shutong Pills(MLST) on posterior limb swelling caused by femur fracture in rats. The rats were randomly divided into a sham operation group, a model group, a low-dose MLST group(1.8 g·kg~(-1)·d~(-1)), a high-dose MLST group(3.6 g·kg~(-1)·d~(-1)), and a positive drug group(60 mg·kg~(-1)·d~(-1) Maizhiling Tablets). The femur in the sham operation group was exposed and the wound was sutured, while the other four groups underwent mechanical damage to cause femur fracture. The rats were treated with corresponding drugs by gavage 7 days before modeling and 5 days after modeling, while those in the sham operation group and the model group were given an equivalent dose of distilled water by gavage. Hematoxylin-eosin(HE) staining was used to detect the pathological injury of the posterior limb muscle tissues in rats, and the degree of hind limb swelling was measured. The enzyme-linked immunosorbent assay(ELISA) kit was used to detect the expression levels of interleukin-6(IL-6), interleukin-1ß(IL-1ß), and tumor necrosis factor-α(TNF-α) in the serum of rats in each group. The activity of superoxide dismutase(SOD), malondialdehyde(MDA), catalase(CAT), and glutathione peroxidase(GSH-Px) in rat serum was also measured. Western blot was used to detect the protein expression levels of heme oxygenase 1(HO-1), NAD(P)H quinone oxidoreductase 1(NQO1), and nuclear transcription factor E2-related factor 2(Nrf2) in rat posterior limb muscle tissues. The changes in the intestinal flora and intestinal metabolites in rats were detected by 16S rDNA sequencing and ultra-performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS), respectively, to explore the underlying mechanism of MLST in treating posterior limb swelling caused by femur fracture in rats. Compared with the model group, MLST significantly improved the degree of posterior limb swelling in rats, reduced the levels of serum inflammatory factors, and alleviated oxidative stress injury. The HE staining results showed that the inflammatory infiltration in the posterior limb muscle tissues of rats in the MLST groups was significantly improved. Western blot results showed that MLST significantly increased the protein expression of HO-1, NQO1, and Nrf2 in rat posterior limb muscle tissues compared with the model group. The 16S rDNA sequencing results showed that MLST improved the disorder of intestinal flora in rats after femur fracture. The UPLC-MS/MS results showed that MLST significantly affected the bile acid biosynthesis and metabolism pathway in the intestine after femur fracture, and the Spearman analysis confirmed that the metabolite deoxycholic acid involved in bile acid biosynthesis was positively correlated with the abundance of Turicibacter. The metabolite cholic acid was positively correlated with the abundance of Papilibacter, Staphylococcus, and Intestinimonas. The metabolite lithocholic acid was positively correlated with Papilibacter and Intestinimonas. The above results indicated that MLST could protect against the posterior limb swelling caused by femur fracture in rats. This protective effect may be achieved by improving the pathological injury of the posterior limb muscle, reducing the expression levels of inflammatory and oxidative stress-related factors in serum, reducing the oxidative injury of the posterior limb muscle, improving intestinal flora, and balancing the biosynthesis of bile acids in the intestine.


Assuntos
Microbioma Gastrointestinal , Fator 2 Relacionado a NF-E2 , Ratos , Animais , Fator 2 Relacionado a NF-E2/metabolismo , Cromatografia Líquida , Tipagem de Sequências Multilocus , Espectrometria de Massas em Tandem , Estresse Oxidativo , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-6/metabolismo , Fêmur , Ácidos e Sais Biliares , DNA Ribossômico , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo
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