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1.
J Bioenerg Biomembr ; 56(4): 405-418, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38842666

RESUMO

BACKGROUND: Ferritinophagy-mediated ferroptosis plays a crucial role in fighting pathogen aggression. The long non-coding RNA Mir22hg is involved in the regulation of ferroptosis and aberrantly overexpression in lipopolysaccharide (LPS)-induced sepsis mice, but whether it regulates sepsis through ferritinophagy-mediated ferroptosis is unclear. METHODS: Mir22hg was screened by bioinformatics analysis. Ferroptosis was assessed by assaying malondialdehyde (MDA), reactive oxygen species (ROS), and Fe2+ levels, glutathione (GSH) activity, as well as ferroptosis-related proteins GPX4 and SLC3A2 by using matched kits and performing western blot. Ferritinophagy was assessed by Lyso tracker staining and FerroOrange staining, immunofluorescence analysis of Ferritin and LC-3, and western blot analysis of LC-3II/I, p62, FTH1, and NCOA4. The bind of YTH domain containing 1 (YTHDC1) to Mir22hg or angiopoietin-like-4 (Angptl4) was verified by RNA pull-down and/or immunoprecipitation (RIP) assays. RESULTS: Mir22hg silencing lightened ferroptosis and ferritinophagy in LPS-induced MLE-12 cells and sepsis mouse models, as presented by the downregulated MDA, ROS, Fe2+, NCOA4, and SLC3A2 levels, upregulated GPX4, GSH, and FTH1 levels, along with a decrease in autophagy. Mir22hg could bind to the m6A reader YTHDC1 without affecting its expression. Mechanistically, Mir22hg enhanced Angptl4 mRNA stability through recruiting the m6A reader YTHDC1. Furthermore, Angptl4 overexpression partly overturned Mir22hg inhibition-mediated effects on ferroptosis and ferritinophagy in LPS-induced MLE-12 cells. CONCLUSION: Mir22hg contributed to in ferritinophagy-mediated ferroptosis in sepsis via recruiting the m6A reader YTHDC1 and strengthening Angptl4 mRNA stability, highlighting that Mir22hg may be a potential target for sepsis treatment based on ferroptosis.


Assuntos
Proteína 4 Semelhante a Angiopoietina , Ferroptose , MicroRNAs , Sepse , Sepse/metabolismo , Camundongos , Animais , MicroRNAs/metabolismo , MicroRNAs/genética , Proteína 4 Semelhante a Angiopoietina/metabolismo , Proteína 4 Semelhante a Angiopoietina/genética , Estabilidade de RNA , Ferritinas/metabolismo , Camundongos Endogâmicos C57BL , Masculino , Humanos , Autofagia/fisiologia
2.
Med Image Anal ; 94: 103109, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38387243

RESUMO

In computational pathology, multiple instance learning (MIL) is widely used to circumvent the computational impasse in giga-pixel whole slide image (WSI) analysis. It usually consists of two stages: patch-level feature extraction and slide-level aggregation. Recently, pretrained models or self-supervised learning have been used to extract patch features, but they suffer from low effectiveness or inefficiency due to overlooking the task-specific supervision provided by slide labels. Here we propose a weakly-supervised Label-Efficient WSI Screening method, dubbed LESS, for cytological WSI analysis with only slide-level labels, which can be effectively applied to small datasets. First, we suggest using variational positive-unlabeled (VPU) learning to uncover hidden labels of both benign and malignant patches. We provide appropriate supervision by using slide-level labels to improve the learning of patch-level features. Next, we take into account the sparse and random arrangement of cells in cytological WSIs. To address this, we propose a strategy to crop patches at multiple scales and utilize a cross-attention vision transformer (CrossViT) to combine information from different scales for WSI classification. The combination of our two steps achieves task-alignment, improving effectiveness and efficiency. We validate the proposed label-efficient method on a urine cytology WSI dataset encompassing 130 samples (13,000 patches) and a breast cytology dataset FNAC 2019 with 212 samples (21,200 patches). The experiment shows that the proposed LESS reaches 84.79%, 85.43%, 91.79% and 78.30% on the urine cytology WSI dataset, and 96.88%, 96.86%, 98.95%, 97.06% on the breast cytology high-resolution-image dataset in terms of accuracy, AUC, sensitivity and specificity. It outperforms state-of-the-art MIL methods on pathology WSIs and realizes automatic cytological WSI cancer screening.


Assuntos
Mama , Processamento de Imagem Assistida por Computador , Humanos
3.
Opt Express ; 31(18): 29768-29781, 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37710770

RESUMO

Graphene(G)-noble metal-ZnO hybrid systems were developed as highly sensitive and recyclable surface enhanced Raman scattering (SERS) platforms, in which ultrathin graphene of varying thickness was embedded between two metallic layers on top of a ZnO layer. Due to the multi-dimensional plasmonic coupling effect, the Au/G/Ag@ZnO multilayer structure possessed ultrahigh sensitivity with the detection limit of Rhodamine 6 G (R6G) as low as 1.0×10-13 mol/L and a high enhancement factor of 5.68×107. Both experimental and simulation results showed that graphene films could significantly regulate the interlayer plasmon resonance coupling strength, and single-layer graphene had the best interlayer regulation effect. Additionally, the SERS substrate structure prepared through physical methods exhibited high uniformity, the graphene component of the substrate possessed excellent molecular enrichment ability and silver oxidation inhibition characteristics, resulting in a substrate with high stability and exceptional reproducibility. The signal change was less than 15%. Simultaneously, due to the excellent photocatalytic performance of the low-cost and wide-band-gap semiconductor material ZnO, the SERS substrate exhibited exceptional reusability. Even after five cycles of adsorption-desorption, the SERS performance remained stable and maintained a reliable detection limit. The study introduced a novel approach to creating multilayer composite SERS substrates that exhibited exceptional performance, offering a new analytical tool with high sensitivity, stability, and reusability.

4.
J Bioenerg Biomembr ; 55(3): 207-217, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37264258

RESUMO

Transient receptor potential melastatin 7 (TRPM7), a non-selective cation channel, was significantly upregulated in the blood of patients with sepsis. This study focuses on the preliminary exploration of the probable regulatory mechanism of TRPM7 in sepsis-induced myocardial injury (SIMI). HL-1 cardiac muscle cell line was treated with lipopolysaccharide (LPS) to mimic SIMI in vitro, and TRPM7 level was assessed. The impacts of TRPM7 knockdown on cellular inflammation response, oxidative stress, apoptosis, endoplasmic reticulum (ER) stress, and ferroptosis were identified. In order to explore the mechanism, ER stress agonist tunicamycin (TM) or ferroptosis inducer erastin was applied to treat HL-1 cells. The influences of TM and erastin on the aforementioned aspects were evaluated. TRPM7 was elevated in response to LPS stimulation, and its knockdown reduced the secretion of inflammatory factors and oxidative stress degree. Moreover, TRPM7 knockdown significantly suppressed cell apoptosis, ER stress, and ferroptosis. TM and erastin reversed the functions of TRPM7 knockdown, indicating ER stress and ferroptosis mediated in the regulation of TRPM7. This research proposes the possibility of TRPM7 as a marker or target for SIMI, and provides theoretical support for follow-up research.


Assuntos
Ferroptose , Sepse , Canais de Cátion TRPM , Humanos , Canais de Cátion TRPM/metabolismo , Lipopolissacarídeos/farmacologia , Apoptose , Estresse do Retículo Endoplasmático/fisiologia , Proteínas Serina-Treonina Quinases/metabolismo
5.
Zhongguo Zhong Yao Za Zhi ; 37(7): 941-5, 2012 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-22792794

RESUMO

OBJECTIVE: To study the chemical constituents from the seeds of Notopterygium franchetii. METHOD: Ethanol extracts of seeds N. franchetii were separated and purified by such methods as normal and reversed phase column chromatographies and thin-layer chromatography and structurally elucidated by MS and NMR evidences. RESULT: Twenty nine compounds were separated, they were isoimperatorin (1), [3-sitosterol (2), phellopterin (3), bergapten (4), N-tetra, hexa, octacosanoylanthranilic acid (5-7), daucosterol (8), oxypeucedanin hydrate (9), umbelliferone (10), demethylfuropinnarin (11), (2S, 3S, 4R, 8E)-2-[(2'R)- 2'-hydroxydoco, trico, tetraco, entaco, hexaco sanosylamino] -octadecene-1, 3, 4-triol (12-16), (-)-oxypeucedanin (17), diosmetin (18), bergaptol-O-beta-D-glucopyranoside (19), nodakenin (20), 1'-O-beta-D-glucopyranosyl-(2R, 3S)-3-hydroxynodakenetin (21), uracil (22), decuroside V (23), 8-O-beta-D-glucopyranosyl-5-hydroxypsoralen (24), 8-O-beta-D-glucopyranosyl-5-methoxylpsoralen (25), diosmin (26), alaschanioside C (27), kynurenic acid (28) and mannitol (29). CONCLUSION: All of these compounds were separated from the seeds of N. franchetii for the first time. Of them, 18, 22, 26 and 29 were firstly obtained from genus Notopterygium.


Assuntos
Apiaceae/química , Sementes/química , 5-Metoxipsoraleno , Cromatografia em Camada Fina , Cumarínicos/química , Diosmina/química , Flavonoides/química , Furocumarinas/química , Glucosídeos/química , Ácido Cinurênico/química , Espectroscopia de Ressonância Magnética , Manitol/química , Metoxaleno/análogos & derivados , Metoxaleno/química , Sitosteroides/química , Uracila/química
6.
Zhongguo Zhong Yao Za Zhi ; 37(1): 57-60, 2012 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-22741462

RESUMO

Twenty-four compounds in the fruits of Forsythia suspensa were isolated and purified by column chromatography and preparative TLC. On the basis of comprehensive spectroscopic methods including IR, ESI-MS/MS, 1D and 2D NMR, these compounds were identified as ten ceremides (1-10), six triterpenes (11-16), one steroids (17), three flavonoids (18-20), two C6-C2 alcohols (21-22) and two lignans (23-24). Compounds 1-10 were reported from F. suspense for the first time, among which 1, 2, 4 and 5 were new ones.


Assuntos
Medicamentos de Ervas Chinesas/química , Forsythia/química , Frutas/química , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/isolamento & purificação , Espectroscopia de Ressonância Magnética , Estrutura Molecular
7.
J Ethnopharmacol ; 138(1): 150-5, 2011 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-21924337

RESUMO

ETHNOPHARMACOLOGICAL SIGNIFICANCE: Panax notoginseng saponins (PNS) are ingredients extracted from traditional Chinese medicinal herb Panax notoginseng. It has been demonstrated that PNS have extensive effects on the cardiovascular system, including inhibition of platelet aggregation, increasing blood flow, improving left ventricular diastolic function in hypertensive patients and anti-inflammatory effect. AIM OF STUDY: Recent researches indicated that PNS administration inhibited foam cells' formation. The present study was designed to study the effects of PNS on atherogenesis and to explore the relevant molecular mechanisms. MATERIALS AND METHODS: The Zymosan A induced atherosclerosis models were used to investigate the anti-atherosclerosis effects of PNS. The integrin express array was used to check the changes of integrins. The foam cell formation was observed with transmission electron microscope. The effect of PNS on phosphorylation of FAK on threonine 397 and protein level of NF-κB was also evaluated in vitro. RESULTS: PNS treated rats had less plaque spots on the aortas compared with Zym induced group. The formation of foam cell was inhibited by PNS. Compared with Zym treated group, the expression of most integrin families decreased except Itgav and Itgb2 after PNS treatment. PNS inhibited phosphorylation of FAK on threonine 397 and translocation of NF-κB. CONCLUSION: High fat diet together with Zym induces atherogenesis of rat. PNS inhibits zymosan A induced atherogenesis by suppressing FAK phosphorylation, integrins expression and NF-κB translocation.


Assuntos
Aterosclerose/prevenção & controle , Quinase 1 de Adesão Focal/metabolismo , Integrinas/metabolismo , NF-kappa B/metabolismo , Panax notoginseng/química , Fitoterapia , Saponinas/uso terapêutico , Animais , Aorta/patologia , Aterosclerose/metabolismo , Aterosclerose/patologia , Transporte Biológico/efeitos dos fármacos , Modelos Animais de Doenças , Células Espumosas/efeitos dos fármacos , Masculino , Fosforilação , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Placa Aterosclerótica/prevenção & controle , Ratos , Ratos Wistar , Saponinas/farmacologia , Treonina/metabolismo , Zimosan
8.
J Asian Nat Prod Res ; 13(5): 409-16, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21534038

RESUMO

Three new flavone C-glycosides, paraquinins A-C, were isolated from the aerial parts of Paraquilegia microphylla (Royle) Dromm. et Hutch, a Tibetan medicine distributed in the Qinghai-Tibet plateau. On the basis of 1D and 2D NMR evidence, their structures were elucidated as acacetin-6-C-ß-D-glucopyranosyl-(1 → 2)-ß-D-glucopyranoside (1), acacetin-6-C-α-L-rhamnopyranosyl-(1 → 2)-ß-D-glucopyranosyl-(1 → 2)-ß-D-glucopyranoside (2), and acacetin-6-C-α-L-rhamnopyranosyl-(1 → 2)-(6'''-O-E-feruloyl)-ß-D-glucopyranosyl-(1 → 2)-ß-D-glucopyranoside (3).


Assuntos
Flavonas/isolamento & purificação , Glicosídeos/isolamento & purificação , Ranunculaceae/química , Flavonas/química , Glicosídeos/química , Medicina Tradicional do Leste Asiático , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Estereoisomerismo , Tibet
10.
Anal Bioanal Chem ; 399(3): 1223-31, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21088827

RESUMO

The chemical composition of herbal medicines is very complex, and their therapeutic effects are determined by multi-components with sophisticated synergistic and/or suppressive actions. Therefore, quality control of herbal medicines has been a formidable challenge. In this work, we describe a fast analytical method that can be used for quality assessment of herbal medicines. The method is based on ligand fishing using human-serum-albumin-functionalized magnetic nanoparticles (HSA-MNPs) and mass spectrometry. To demonstrate the applicability of the proposed method, eight samples of Dioscorea panthaica were analyzed. The sampled plants were of both wild and cultivated origins. They grew at different geographical locations and were harvested at different times. The ligands bound to HSA-MNPs were isolated from the plant extracts and detected by using direct infusion electrospray ionization mass spectrometry (DI-ESI-MS). Chemical identity has been confirmed for five of the ligands isolated. From more than 15 peaks in the ESI-MS spectrum, 11 common peaks were selected for calculating the correlation coefficient and cosine ratio. The values of correlation coefficient and cosine ratio were >0.9824 and >0.9988, respectively, for all the samples tested. The results indicated a high level of similarity among the eight D. panthaica samples. Compared with chromatographic fingerprint analysis, the proposed HSA-MNP-based DI-ESI-MS/MS approach was not only fast and easy to carry out but also biological-activity-oriented, promising a more effective data interpretation and thus reliable assessment conclusions.


Assuntos
Dioscorea/química , Medicamentos de Ervas Chinesas/análise , Nanopartículas de Magnetita/química , Extratos Vegetais/análise , Albumina Sérica/química , Humanos , Ligantes , Conformação Molecular , Controle de Qualidade , Espectrometria de Massas por Ionização por Electrospray , Estereoisomerismo
11.
Org Lett ; 13(3): 462-5, 2011 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-21174449

RESUMO

An unprecedented dimeric triterpenoid, designated dibelamcandal A, with a six-membered ring linking two iridal type triterpenoid nuclei, was isolated from the rhizome of Belamcanda chinensis. Its structure was determined by extensive spectroscopic measurements, including IR, ESI-MS, HR-ESI-MS, and 1D and 2D NMR. It demonstrated significant molluscicide activity against Pomacea canaliculata.


Assuntos
Iridaceae/química , Moluscocidas/isolamento & purificação , Moluscocidas/farmacologia , Caramujos/efeitos dos fármacos , Triterpenos/isolamento & purificação , Triterpenos/farmacologia , Animais , Estrutura Molecular , Moluscocidas/química , Ressonância Magnética Nuclear Biomolecular , Rizoma/química , Triterpenos/química
12.
Rapid Commun Mass Spectrom ; 24(22): 3335-9, 2010 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-20973009

RESUMO

The chemical diversity of secondary metabolites in medicinal plant makes it a huge challenge to isolate the bioactive compounds from herbal extracts, so quick recognition of the bioactive ones is of vital importance for improving the efficiency of isolation. In this study, a ligand fishing experiment based on human serum albumin functionalized magnetic nano-particles (HSA-MNPs) was performed to probe the bioactive components in a traditional Chinese medicinal plant, Dioscorea panthaica. The minor compounds fished out by HSA-MNPs were identified by electrospray ionization mass spectrometry (ESI-MS), and then separated from the extract of the whole plant by one or two steps of column chromatography under the guidance of ESI-MS. Four biologically active compounds, progenin II, progenin III, dioscin and gracillin, were isolated much faster than in the normal lengthy phytochemical procedure. The present study demonstrates that biological macromolecule (protein, enzyme, receptor, et al.) functionalized MNPs may serve as baits to recognize bioactive small molecules in complex herbal extracts. It is expected that a macromolecule functionalized MNPs-based ligand fishing experiment coupled with ESI-MS may accelerate the process of identification and isolation of bioactive components from medicinal plants, and thus benefit the speed of drug discovery.


Assuntos
Dioscorea/química , Medicamentos de Ervas Chinesas/química , Nanopartículas de Magnetita/química , Albumina Sérica/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Espirostanos/química , Medicamentos de Ervas Chinesas/metabolismo , Humanos , Técnicas de Sonda Molecular , Sondas Moleculares/química
14.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 20(1): 91-4, 100, 2003 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-12744172

RESUMO

This study was aimed to assess the effect of Shenfu injection on different circulation state. Using a microcirculation microscope system, we observed mice's auricle micro-artery diameter, density of capillary, blood velocity in different circulation state (i.e. normal state, epinephrine or endotoxin induced microcirculation disturbance state) after administering Shenfu injection into their caudal vein, and we compared the Shenfu group with Shenmai group and Dexamethasone group. The results showed that Shenfu injection causes the auricle microartery diameter to enlarge and the density of capillary and blood velocity to increase in different microcirculation state, and such effect is especially notable on the epinephrine induced microcirculation disturbance group and endotoxin induced microcirculation disturbance group; the effect of Shenfu injection is stronger than that of Shenmai injection and similar to Dexamethasone injection. In addition, Shenfu injection was shown to have remarkable effect on resisting the lowering of limb temperature when the mice are attacked by endotoxin.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Microcirculação/fisiologia , Animais , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Medicamentos de Ervas Chinesas/administração & dosagem , Orelha/irrigação sanguínea , Endotoxinas/toxicidade , Epinefrina/toxicidade , Feminino , Injeções , Masculino , Camundongos , Microcirculação/efeitos dos fármacos
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