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1.
Nature ; 620(7974): 651-659, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37468627

RESUMO

Even among genetically identical cancer cells, resistance to therapy frequently emerges from a small subset of those cells1-7. Molecular differences in rare individual cells in the initial population enable certain cells to become resistant to therapy7-9; however, comparatively little is known about the variability in the resistance outcomes. Here we develop and apply FateMap, a framework that combines DNA barcoding with single-cell RNA sequencing, to reveal the fates of hundreds of thousands of clones exposed to anti-cancer therapies. We show that resistant clones emerging from single-cell-derived cancer cells adopt molecularly, morphologically and functionally distinct resistant types. These resistant types are largely predetermined by molecular differences between cells before drug addition and not by extrinsic factors. Changes in the dose and type of drug can switch the resistant type of an initial cell, resulting in the generation and elimination of certain resistant types. Samples from patients show evidence for the existence of these resistant types in a clinical context. We observed diversity in resistant types across several single-cell-derived cancer cell lines and cell types treated with a variety of drugs. The diversity of resistant types as a result of the variability in intrinsic cell states may be a generic feature of responses to external cues.


Assuntos
Antineoplásicos , Células Clonais , Resistencia a Medicamentos Antineoplásicos , Neoplasias , Humanos , Células Clonais/efeitos dos fármacos , Células Clonais/metabolismo , Células Clonais/patologia , Código de Barras de DNA Taxonômico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/patologia , RNA-Seq , Análise da Expressão Gênica de Célula Única , Células Tumorais Cultivadas , Antineoplásicos/farmacologia
2.
Proc Natl Acad Sci U S A ; 120(8): e2206878120, 2023 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-36791099

RESUMO

SET is a multifunctional histone-binding oncoprotein that regulates transcription by an unclear mechanism. Here we show that SET enhances estrogen-dependent transcription. SET knockdown abrogates transcription of estrogen-responsive genes and their enhancer RNAs. In response to 17ß-estradiol (E2), SET binds to the estrogen receptor α (ERα) and is recruited to ERα-bound enhancers and promoters at estrogen response elements (EREs). SET functions as a histone H2 chaperone that dynamically associates with H2A.Z via its acidic C-terminal domain and promotes H2A.Z incorporation, ERα, MLL1, and KDM3A loading and modulates histone methylation at EREs. SET depletion diminishes recruitment of condensin complexes to EREs and impairs E2-dependent enhancer-promoter looping. Thus, SET boosts E2-induced gene expression by establishing an active chromatin structure at ERα-bound enhancers and promoters, which is essential for transcriptional activation.


Assuntos
Cromatina , Histonas , Cromatina/genética , Histonas/genética , Histonas/metabolismo , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Linhagem Celular Tumoral , Estrogênios/metabolismo , Estradiol/farmacologia , Proteínas Oncogênicas/metabolismo , Transcrição Gênica
3.
Sensors (Basel) ; 23(10)2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37430702

RESUMO

Damping is an important factor contributing to errors in the measurement of rotational inertia using the torsion pendulum method. Identifying the system damping allows for minimizing the measurement errors of rotational inertia, and accurate continuous sampling of torsional vibration angular displacement is the key to realizing system damping identification. To address this issue, this paper proposes a novel method for measuring the rotational inertia of rigid bodies based on monocular vision and the torsion pendulum method. In this study, a mathematical model of torsional oscillation under a linear damping condition is established, and an analytical relationship between the damping coefficient, torsional period, and measured rotational inertia is obtained. A high-speed industrial camera is used to continuously photograph the markers on a torsion vibration motion test bench. After several data processing steps, including image preprocessing, edge detection, and feature extraction, with the aid of a geometric model of the imaging system, the angular displacement of each frame of the image corresponding to the torsion vibration motion is calculated. From the characteristic points on the angular displacement curve, the period and amplitude modulation parameters of the torsion vibration motion can be obtained, and finally the rotational inertia of the load can be derived. The experimental results demonstrate that the proposed method and system described in this paper can achieve accurate measurements of the rotational inertia of objects. Within the range of 0-100 × 10-3 kg·m2, the standard deviation of the measurements is better than 0.90 × 10-4 kg·m2, and the absolute value of the measurement error is less than 2.00 × 10-4 kg·m2. Compared to conventional torsion pendulum methods, the proposed method effectively identifies damping using machine vision, thereby significantly reducing measurement errors caused by damping. The system has a simple structure, low cost, and promising prospects for practical applications.

4.
Small ; 18(13): e2106863, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35076167

RESUMO

Carbonized polymer dots (CPDs) have received tremendous attention during the last decade due to their excellent fluorescent properties and catalytic performance. Doping CPDs with transition metal atoms accelerates the local electron flow in CPDs and improves the fluorescent properties and catalytic performance of the CPDs. However, the binding sites and the formation mechanisms of the transition-metal-atom-doped CPDs remain inconclusive. In this work, Mn2+ -ion-doped CPDs (Mn-CPDs) are synthesized by the hydrothermal method. The Mn2+ ions form MnO bonds that bridge the sp2 domains of carbon cores and increases the effective sp2 domains in the Mn-CPDs, which redshifts the fluorescence emission peak of the Mn-CPDs slightly. The Mn2+ ions form covalent bonds in the CPDs and remedy the oxygen vacancies of the CPDs, which cuts off the non-radiative-recombination process of the Mn-CPDs and increases the quantum yield of the Mn-CPDs to 70%. Furthermore, the MnO bonds accelerate the electron flow between adjacent sp2 domains and enhances the electron transport in the Mn-CPDs. Thus, the Mn-CPDs demonstrate excellent catalytic performance to activate hydrogen peroxide (H2 O2 ) and produce hydroxyl radicals (•OH) to degrade methylene blue (MB) and rhodamine B (RhB).


Assuntos
Polímeros , Pontos Quânticos , Carbono/química , Transporte de Elétrons , Fluorescência , Polímeros/química , Pontos Quânticos/química
5.
Plant Physiol ; 186(2): 1186-1201, 2021 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-33693800

RESUMO

As day-neutral (DN) woody perennial plants, the flowering time of roses (Rosa spp.) is assumed to be independent of the photoperiodic conditions; however, light responses of rose plants are not well understood. Chinese rose (Rosa chinensis) plants were grown under two light intensities (low light [LL], 92 µmol·m-2·s-1; or high light [HL], 278 µmol·m-2·s-1), and either with or without an end-of-day far-red (EOD-FR) treatment. Flowering was significantly delayed in the LL condition compared with the HL, but was not affected by EOD-FR treatment. The time until flowering positively corresponded with the mRNA and protein levels of phytochrome-interacting factors (PIFs; RcPIFs). The heterologous expression of RcPIF1, RcPIF3, or RcPIF4 in the Arabidopsis (Arabidopsis thaliana) pifq quadruple mutant partially rescued the mutant's shorter hypocotyl length. Simultaneous silencing of three RcPIFs in R. chinensis accelerated flowering under both LL and HL, with a more robust effect in LL, establishing RcPIFs as flowering suppressors in response to light intensity. The RcPIFs interacted with the transcription factor CONSTANS (RcCO) to form a RcPIFs-RcCO complex, which interfered with the binding of RcCO to the promoter of FLOWERING LOCUS T (RcFT), thereby inhibiting its expression. Furthermore, this inhibition was enhanced when RcPIFs were stabilized by LL, leading to delayed flowering under LL compared with HL. Our results not only revealed another layer of PIF functioning in the flowering of woody perennial plants, but also established a mechanism of light response in DN plants.


Assuntos
Fitocromo/metabolismo , Proteínas de Plantas/metabolismo , Rosa/genética , Arabidopsis/genética , Arabidopsis/fisiologia , Flores/genética , Flores/fisiologia , Flores/efeitos da radiação , Expressão Gênica , Hipocótilo/genética , Hipocótilo/fisiologia , Hipocótilo/efeitos da radiação , Mutação , Fotoperíodo , Proteínas de Plantas/genética , Rosa/fisiologia , Rosa/efeitos da radiação , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transgenes
6.
Int J Mol Sci ; 23(13)2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35806340

RESUMO

Pseudo-response regulators (PRRs) are the important genes for flowering in roses. In this work, clock PRRs were genome-wide identified using Arabidopsis protein sequences as queries, and their evolutionary analyses were deliberated intensively in Rosaceae in correspondence with angiosperms species. To draw a comparative network and flow of clock PRRs in roses, a co-expression network of flowering pathway genes was drawn using a string database, and their functional analysis was studied by silencing using VIGS and protein-to-protein interaction. We revealed that the clock PRRs were significantly expanded in Rosaceae and were divided into three major clades, i.e., PRR5/9 (clade 1), PRR3/7 (clade 2), and TOC1/PRR1 (clade 3), based on their phylogeny. Within the clades, five clock PRRs were identified in Rosa chinensis. Clock PRRs had conserved RR domain and shared similar features, suggesting the duplication occurred during evolution. Divergence analysis indicated the role of duplication events in the expansion of clock PRRs. The diverse cis elements and interaction of clock PRRs with miRNAs suggested their role in plant development. Co-expression network analysis showed that the clock PRRs from Rosa chinensis had a strong association with flowering controlling genes. Further silencing of RcPRR1b and RcPRR5 in Rosa chinensis using VIGS led to earlier flowering, confirming them as negative flowering regulators. The protein-to-protein interactions between RcPRR1a/RcPRR5 and RcCO suggested that RcPRR1a/RcPRR5 may suppress flowering by interfering with the binding of RcCO to the promoter of RcFT. Collectively, these results provided an understanding of the evolutionary profiles as well as the functional role of clock PRRs in controlling flowering in roses.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Rosa , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Ritmo Circadiano/fisiologia , Flores/metabolismo , Regulação da Expressão Gênica de Plantas , Rosa/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
7.
Soft Matter ; 16(14): 3548-3554, 2020 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-32219248

RESUMO

Due to the poor heat-resistance and intrinsic weakness of the bridging moieties in aerogel matrixes, it remains greatly challenging to fabricate highly thermostable and toughened silsesquioxane aerogels. By utilizing bismaleimide as the bridging part and optimizing the solvent polarity, lightweight (ρ < 0.09 g cm-3), compressible (80% strain) and superhydrophobic (CA ≈ 150°) bismaleimide bridged silsesquioxane aerogels (BMIT-BSAs) are constructed. The microstructure and compressive modulus of BMIT-BSAs can be tuned by the sol-gel solvents with different polarities. Moreover, stable low-temperature wettability at -196 °C and a significantly increased initial deposition temperature of 336 °C for both N2 and O2 atmospheres were measured, demonstrating the wide temperature tolerance of BMIT-BSAs.

8.
Nanomedicine ; 24: 102135, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31843660

RESUMO

The upconversion nanoparticles (UCNPs) exhibit versatility applications aiming at biological domains for decades on account of superior optical characteristics. Nevertheless, the UCNPs are confronted with tremendous difficulties in biological field owing to large grain size, low fluorescence efficiency, and single function. Herein, the small-sized CaF2: Yb3+/Er3+ UCNPs coated with NaGdF4 shells (activator and inert, UCNPs-RBHA-Pt-PEG) not only burst out strong fluorescence, but also provide prominent diagnosability by taking advantage of magnetic resonance (MR) imaging as well as temperature sensing and inhibiting capability for CT26 tumor tissues based on synergetic therapy modality of photodynamic therapy (PDT) and chemotherapy. Ultimately, the tumor sizes decrease visibly after injected with UCNPs-RBHA-Pt-PEG and simultaneously irradiated with near infrared (NIR) light at low power density (0.35 W/cm2, 6 min). In summary, the small-sized and strong-fluorescent single nanoparticles with multi-functions may provide a valuable enlightenment for diagnosis and treatment of cancer in the future.


Assuntos
Nanopartículas/química , Animais , Fluoreto de Cálcio/química , Linhagem Celular Tumoral , Camundongos , Modelos Teóricos , Espécies Reativas de Oxigênio/metabolismo , Temperatura , Raios Ultravioleta
9.
Inorg Chem ; 56(19): 11900-11910, 2017 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-28926231

RESUMO

Narrow band red-emitting A2GeF6:Mn4+ (A = Na, K, Rb, Cs) phosphors were prepared through a two-step precipitation-cation exchange route using a K2MnF6 precursor as the Mn4+ source. The phase purity, morphology, and constituent were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectric spectroscopy (XPS), and electron paramagnetic resonance (EPR) examination. Optical properties were investigated by photoluminescence spectra (PL and PLE) and high-resolution PL. A temperature-dependent PL examination was performed to investigate the electron-phonon coupling emission mechanism of Mn4+ in these alkali fluorogermanates. The PL data show that both ordered distribution and appropriate distance between Mn4+ ions are propitious for enhancement of the emission intensity. A resonance emission enhancement (REE) mechanism has been proposed to explain the intensity increment among these products. These phosphors present bright red emission under blue light (467 nm) illumination, among which Cs2GeF6:0.03Mn4+ exhibits the most excellent optical properties with a quantum yield (QY) of 93%. A WLED (white light-emitting diode) fabricated with blend of commercial YAG:Ce3+ and this phosphor emits intense warm white light with low color temperature (CCT = 3385 K) and high color rendering index (Ra = 90.5), implying its potential application as red phosphor in WLEDs.

10.
Nanotechnology ; 27(47): 475709, 2016 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-27782002

RESUMO

We fabricated a high-performance film heater based on a silver nanowire and polymethyl methacrylate (Ag NW-PMMA) composite film, which was synthesized with the assistance of mechanical lamination and an in situ transfer method. The films exhibit excellent conductivity, high figure of merit, and strong adhesion of percolation network to substrate. By controlling NW density, we prepared the films with a transmittance of 44.9-85.0% at 550 nm and a sheet resistance of 0.13-1.40 Ω sq-1. A stable temperature ranging from 130 °C-40 °C was generated at 3.0 V within 10-30 s, indicating that the resulting film heaters show a rapid thermal response, low driving voltage and stable temperature recoverability. Furthermore, we demonstrated the applications of the film heater in defrosting and a physical therapeutic instrument. A fast defrosting on the composite film with a transmittance of 88% was observed by applying a 9 V driving voltage for 20 s. Meanwhile, we developed a physical therapeutic instrument with two modes of thermotherapy and electronic-pulse massage by using the composite films as two electrodes, greatly decreasing the weight and power consumption compared to a traditional instrument. Therefore, Ag NW-PMMA film can be a promising candidate for diversified heating applications.

11.
Phys Chem Chem Phys ; 18(35): 24350-5, 2016 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-27531313

RESUMO

Using first-principle calculations, we report for the first time, the changes in electronic structures of a single bilayer Sn stacked on a single bilayer Sb(Bi) and on a single quintuple layer Sb2Te3 induced by both interface polarization and strain. With BL Bi and QL Sb2Te3 substrates, the stanene tends to have a low-buckled configuration, whereas with BL Sb substrate, the stanene prefers to form high-buckled configurations. For strained Sn/Sb(Bi) system, we find that the Dirac cone state is not present in the band gap, whereas in strained Sn/Sb2Te3 system, spin-polarized Dirac cone can be introduced into the band gap. We discuss why tensile strain can result in the Dirac cone emerging at the K point based on a tight-binding lattice model. This theoretical study implies the feasibility of realizing quantum phase transitions for Sn thin films on suitable substrates. Our findings provide an effective manner in manipulating electronic structures and topological states in interfacial systems by using interface polarization and strain, which opens a new route for realizing atomically thin spintronic devices.

12.
Zhongguo Zhong Yao Za Zhi ; 41(2): 216-219, 2016 Jan.
Artigo em Zh | MEDLINE | ID: mdl-28861966

RESUMO

To research the intestinal toxicity of n-BuOH fraction in Phytolacca Radix before and after being processed with vinegar. Toxic n-BuOH fractions were separated from Phytolacca Radix. In the animal model, the level of intestinal edema, water content of intestine and stool, IC50 values of HT-29 and IEC-6 were detected with MTT method to compare the changes in toxicity of n-BuOH fractions from Phytolacca Radix before and after being processed with vinegar. n-BuOH fractions of Phytolacca Radix could cause intestinal edema in mice, increase the edema of duodenum, jejunum and the water content in stool, inhibit the proliferation of HT-29 cells and IEC-6 cells, indicating its intestinal toxicity, with HT-29 IC50 at 14.59 mg•L⁻¹ and IEC-6 IC50 at 43.77 mg•L⁻¹. After being processed with vinegar, the level of intestinal edema, edema of duodenum and jejunum and the water content in stool and inhibition ratio of cells line were reduced, with HT-29 IC50 at 58.51 mg•L⁻¹ and IEC-6 IC50 at 84.37 mg•L⁻¹. After being processed with vinegar, the toxicity of n-BuOH fractions from Phytolacca Radix decreased obviously.


Assuntos
Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/isolamento & purificação , Edema/tratamento farmacológico , Phytolacca/química , Ácido Acético/química , Animais , Química Farmacêutica , Medicamentos de Ervas Chinesas/química , Edema/imunologia , Humanos , Intestinos/efeitos dos fármacos , Intestinos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Raízes de Plantas/química
13.
Zhongguo Zhong Yao Za Zhi ; 41(6): 1087-1092, 2016 Mar.
Artigo em Zh | MEDLINE | ID: mdl-28875675

RESUMO

This study was to investigate the mechanism of gingerols antagonizing the inflammatory effect of toxic raphides from Pinella pedatisecta. Mice peritonitis models induced by toxic raphides from P. pedatisecta were applied to observe the effect of gingerols on inflammatory mediators PGE2 in the exudates of abdominal inflammation in mice; rats peritoneal macrophage in vitro culture models were adopted to study the anti-inflammatory effects of gingerol against toxic raphides, with TNF-α and IL-1ß in supernatant as indexes. Scanning electron microscopy was used to observe the changes in surface morphology of macrophages treated by raphides and gingerols. Macrophages-neutrophils co-cultured models were used to study the antagonism of gingerols against the effect of toxic raphides' stimulation on neutrophils migration. Results showed that gingerols could significantly inhibit the production of PGE2 in the exudates of abdominal inflammation induced by toxic raphides from P. pedatisecta in mice. Gingerols could significantly inhibit the toxic raphides from P. pedatisecta to induce the release of inflammatory factors, with certain dose dependence. Scanning electron microscopy showed that gingerols could significantly inhibit phagocytosis of macrophages, cytomembrane injury, and neutrophils migration induced by toxic raphides from P. pedatisecta. The results showed that the antagonism mechanism of gingerols against the toxic raphides from P. pedatisecta may be associated with inhibiting the pro-inflammatory toxicity including macrophage activation, inflammatory factors release, and neutrophils migration.


Assuntos
Anti-Inflamatórios/administração & dosagem , Catecóis/antagonistas & inibidores , Medicamentos de Ervas Chinesas/toxicidade , Álcoois Graxos/antagonistas & inibidores , Inflamação/tratamento farmacológico , Pinellia/toxicidade , Animais , Catecóis/administração & dosagem , Modelos Animais de Doenças , Antagonismo de Drogas , Álcoois Graxos/administração & dosagem , Humanos , Inflamação/etiologia , Inflamação/imunologia , Interleucina-1beta/imunologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Neutrófilos/efeitos dos fármacos , Neutrófilos/imunologia , Fagocitose/efeitos dos fármacos , Pinellia/química , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/imunologia
14.
J Sep Sci ; 38(10): 1691-9, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25764522

RESUMO

Flos Sophorae and its processed product have been clinically used to treat hemorrhage. In this study, the total ion chromatographic fingerprints of the heating products of total flavonoids in Flos Sophorae were established by high-performance liquid chromatography with tandem mass spectrometry and the hemostatic activities were studied by hemostatic screening tests in vivo. The spectrum-effect relationships between fingerprints and hemostatic activities were investigated using canonical correlation analysis to trace the peaks responsible for the hemostatic effects. The predicted active peaks in fingerprints were isolated by column chromatography and their structures were identified by NMR spectroscopy and mass spectrometry. The hemostatic activities of them were verified by platelet aggregation and procoagulation assays in vitro. Canonical correlation analysis results showed that peak 8 and peak 11 were correlated most closely, thus probably being the main hemostatic compounds. Through column chromatography separation, peak 8 (compound I) and peak 11 (compound II) were obtained with purities of 95.61 and 93.38%, respectively, and were discovered new hemostatic compounds named as huaicarbon A (I) and huaicarbon B (II), respectively. This study provides a universal model to trace the active compounds of other herbs which have bioactivity enhancement after processing by spectrum-effect relationships and column chromatography.


Assuntos
Flavonoides/química , Hemostáticos , Medicina Tradicional Chinesa , Animais , Cromatografia Líquida de Alta Pressão , Feminino , Temperatura Alta , Masculino , Ratos , Ratos Wistar , Espectrometria de Massas em Tandem
15.
Molecules ; 20(10): 18352-66, 2015 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-26457703

RESUMO

The Traditional Chinese Medicine herbs Pollen Typhae and Pollen Typhae Carbonisatus have been used as a hemostatic medicine promoting blood clotting for thousands of years. In this study, a reliable, highly sensitive method based on LC-MS/MS has been developed for differentiation of the heating products of total flavonoids in Pollen Typhae (FPT-N). Twenty three peaks were detected and 18 peaks have been structurally identified by comparing retention times, high resolution mass spectrometry data, and fragment ions with those of the reference substances and/or literature data. Additionally, 15 compounds have been quantified by multiple reaction monitoring in the negative ionization mode. It was found that the contents of the characterized compounds differed greatly from each other in FPT-N samples. Among them, the content of huaicarbon B significantly increased at first, while it decreased after heating for 25 min, which could be considered as the characteristic component for distinguishing FPT-N. The present study provided an approach to rapidly distinguish the differences of FPT-N samples. In addition, the actively summarized characteristic fragmentation might help deducing the structure of unknown flavonols compounds. Furthermore, transformation rules of flavonoids during the heating process in carbonisatus development could contribute to hemostatic therapeutic component exploration.


Assuntos
Flavonoides/análise , Pólen/química , Typhaceae/química , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/análise , Medicamentos de Ervas Chinesas/química , Flavonoides/química , Temperatura Alta , Estrutura Molecular , Espectrometria de Massas em Tandem/métodos
16.
Molecules ; 20(9): 16970-86, 2015 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-26393545

RESUMO

Platycladi cacumen and its processed product have been utilized as a Chinese medicine to treat hemorrhages. In this study, the base peak chromatogram fingerprints of heating products of total flavonoids in Platycladi cacumen were established by high performance liquid chromatography coupled with mass spectroscopy/mass spectroscopy (HPLC-MS/MS), and the hemostatic activities were studied by hemostatic screening tests in vivo. The spectrum-effect relationships between fingerprints and hemostatic activities were analyzed by using canonical correlation analysis to trace the peaks responsible for the significant hemostatic effects. Peak 10 and peak 12 were correlated most closely, thus probably being the main hemostatic compounds. To confirm the reliability of this strategy, the targeted unknown peak was obtained by bioactivity-guided isolation, characterized by MS, ¹H-NMR, (13)C-NMR, and 2D-NMR spectroscopies, and referred to as cecarbon as a new compound. In addition, the isolated compound exhibited hemostatic effect in a dose-dependent manner with different potencies in vitro and existed in Platycladi cacumen Carbonisatus. A novel dereplication strategy was employed to trace and identify the active compounds of other herbs that have bioactivity enhancement after processing using spectrum-effect relationships and column chromatography.


Assuntos
Cupressaceae/química , Medicamentos de Ervas Chinesas/química , Flavonoides/química , Hemostáticos/química , Animais , Plaquetas/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/farmacologia , Feminino , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Hemostáticos/farmacologia , Temperatura Alta , Masculino , Estrutura Molecular , Ratos , Espectrometria de Massas em Tandem
17.
Zhongguo Zhong Yao Za Zhi ; 40(23): 4603-8, 2015 Dec.
Artigo em Zh | MEDLINE | ID: mdl-27141670

RESUMO

To look for the toxicity fraction of Euphorbia pekinensis and discuss the vinegar processing mechanism. The level of intestinal edema, water content of intestine and stool, IC50 values of IEC-6 were applied to evaluate the toxicity of different fractions. RT-PCR was employed for detecting AQP1, AQP3 mRNA expression. The petroleum ether (PE) fraction and ethyl acetate (EtOAc) fraction could significant cause intestinal edema in mice, increase the water content of duodenum, colon and stool, inhibited the mRNA expression of AQP1 and increased the mRNA level of AQP3 in colon, and the petroleum ether (PE) fraction was more poisonous. After the petroleum ether (PE) fraction was processed with vinegar, the level of intestinal edema, water content of duodenum, colon, stool and inhibition ratio of cells line were reduced. And we compared the composition change after vinegar processing, finding that the conpekinensis.


Assuntos
Química Farmacêutica/métodos , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/toxicidade , Euphorbia/química , Ácido Acético/química , Animais , Linhagem Celular , Euphorbia/toxicidade , Masculino , Camundongos , Camundongos Endogâmicos ICR , Estrutura Molecular
18.
Plants (Basel) ; 13(1)2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38202450

RESUMO

High temperature is the most important environmental factor limiting potato (Solanum tuberosum L.) yield. The tuber yield has been used to evaluate the heat tolerance of some potato cultivars, but potato yield was closely correlated with the maturation period. Therefore, it is necessary to employ different parameters to comprehensively analyze and evaluate potato tolerance to heat stress. This study aimed to investigate physiologic changes during growth and development, and develop accurate heat tolerance evaluation methods of potato cultivars under heat stress. About 93 cultivars (including foreign elite lines, local landraces and cultivars) were screened using an in vitro tuber-inducing system (continuous darkness and 8% sucrose in the culture medium) under heat stress (30 °C) and normal (22 °C) conditions for 30 days. The tuber yield and number decreased significantly under heat stress compared to the control. A total of 42 cultivars were initially selected depending on tuber formation, after in vitro screening, further testing of selected cultivars was conducted in ex vitro conditions. The screened cultivars were further exposed to heat stress (35 °C/28 °C, day/night) for 60 days. Heat stress led to an increase in the plant height growth rate, fourth internode growth rate, and membrane damage, and due to heat-induced damage to chloroplasts, decrease in chlorophyll biosynthesis and photosynthetic efficiency. Three principal components were extracted by principal component analysis. Correlation and regression analysis showed that heat tolerance is positively correlated with the plant height growth rate, fourth internode growth rate, the content of chlorophyll b, photosynthetic rate, stomatal conductance, transpiration rate, tuber number, and tuber yield, and negatively correlated with the cell membrane injury level. The nine traits are accurate and representative indicators for evaluating potato tolerance to heat stress and could determine a relatively high mean forecast accuracy of 100.0% for the comprehensive evaluation value. Through cluster analysis and screening, cultivar FA, D73, and C132 had the highest heat comprehensive evaluation value, which could be further selected as heat-resistant varieties. This study provides insights into the different physiological mechanisms and accurate evaluation methods of potato cultivars under heat stress, which could be valuable for further research and breeding.

19.
BMC Chem ; 18(1): 91, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38724989

RESUMO

To improve the thermal and combustion properties of nanothermites, a design theory of changing the state of matter and structural state of the reactants during reaction was proposed. The Al/MoO3/KClO4 (Kp) nanothermite was prepared and the Al/MoO3 nanothermite was used as a control. SEM and XRD were used to characterize the nanothermites; DSC was used to test thermal properties; and constant volume and open combustion tests were performed to examine their combustion performance. Phase and morphology characterization of the combustion products were performed to reveal the mechanism of the aluminothermic reaction. The results show that the Al/MoO3/Kp nanothermite exhibited excellent thermal properties, with a total heat release of 1976 J·g- 1, increasing by approximately 33% of 1486 J·g- 1 of the Al/MoO3 nanothermite, and activation energy of 269.66 kJ·mol- 1, which demonstrated higher stability than the Al/MoO3 nanothermite (205.64 kJ·mol- 1). During the combustion test, the peak pressure of the Al/MoO3/Kp nanothermite was 0.751 MPa, and the average pressure rise rate was 25.03 MPa·s- 1, much higher than 0.188 MPa and 6.27 MPa·s- 1 of the Al/MoO3 nanothermite. The combustion products of Al/MoO3 nanothermite were Al2O3, MoO, and Mo, indicating insufficient combustion and incomplete reaction, whereas, the combustion products of Al/MoO3/Kp nanothermite were Al2O3, MoO, and KCl, indicating complete reaction. Their "coral-like" morphology was the effect of reactants solidifying after melting during the combustion process. The characterization of reactants and pressure test during combustion reveals the three stages of aluminothermic reaction in thermites. The excellent thermal and combustion performance of Al/MoO3/Kp nanothermite is attributed to the melt and decomposition of Kp into O2 in the third stage. This study provides new ideas and guidance for the design of high-performance nanothermites.

20.
J Ethnopharmacol ; 303: 115894, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36356715

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Shuangshen Pingfei formula (SSPF), a Chinese medicine prescription, has been prescribed to alleviate PF. However, little is known about the molecular mechanism underlying PF progression and the regulatory mechanism in SSPF. AIMS OF THE STUDY: To discriminate the molecular alterations underlying the development of pulmonary fibrosis (PF) and reveal the regulatory mechanism of Shuangshen Pingfei formula (SSPF). MATERIALS AND METHODS: An integrated analysis of a time-course pathology combined with proteomics and metabolomics was performed to investigate changes in body weight, survival rate, lung coefficient, histopathology, proteins, and metabolites of lung tissues at different time points upon bleomycin (BLM) exposure and SSPF treatment. RESULTS: The results showed that PF progression was characterized by gradually aggravated fibrosis accompanied by inflammation with extended exposure (7, 14, and 21 days). SSPF significantly attenuated lung fibrosis, as evidenced by increased weight, and reduced lung coefficients and fibrosis scores. Moreover, 368 common differentially expressed proteins (DEPs) were identified, and 102 DEPs were continuously and monotonically upregulated via proteomics among the three BLM treatments. The DEPs were principally involved in extracellular matrix (ECM) remodeling and arginine and proline (AP) metabolic reprogramming. Additionally, metabolomics analyses revealed that BLM exposure mainly affected six metabolism pathways, including 34 differentially regulated metabolites (DRMs). Furthermore, correlation analysis found that several DEPs and DRMs, including L-ornithine, S-adenosyl-L-methionine, ARG, and AOC1, were associated with arginine and proline metabolism, and 8,9-EET, 8,9-DHET, CYP2B, etc., were involved in arachidonic acid (AA) metabolism, suggesting that these two pathways play a critical role in the development of fibrosis. After SSPF treatment, the related protein expression and metabolic disorders were regulated, implying that SSPF provides potential solutions to target these pathways for benefit in the treatment of PF. CONCLUSION: Our data suggest that ECM remodeling, and metabolic reprogramming of AP and AA are distinctive features of PF development. Simultaneously, we confirmed that SSPF could effectively regulate metabolic disorders, indicating its potential clinical application for PF therapy. Our findings using multiple approaches provide a molecular-scale perspective on the mechanisms of PF progression and the amelioration of SSPF.


Assuntos
Fibrose Pulmonar , Humanos , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/tratamento farmacológico , Fibrose Pulmonar/metabolismo , Proteômica , Bleomicina , Metabolômica , Prolina , Arginina
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