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1.
Anal Chim Acta ; 1182: 338941, 2021 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-34602200

RESUMO

It is the first time to investigate local distribution patterns of mercury (Hg) in mice organs after Hg and Se exposure with detection of laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). Two batch of adult mice were employed to be exposed to inorganic mercury (iHg) and methylmercury (MeHg) with or without Se at the dose of 55 µmol kg-1. Tissue sections of brain, kidney, liver, and spleen from one batch mice were prepared to get local imaging of Hg by LA-ICP-MS. Tissues from another batch mice were used to quantify Hg and Se in tissues with ICP-MS after acid digestion. The results indicated that, for mice exposed to iHg, Hg mainly distributed in kidney, a little in liver, and hardly in brain and spleen; for mice exposed to MeHg, lower amount of Hg was found in kidney, liver and spleen, and almost no Hg was found in brain. It was interesting that for Hg and Se co-administration groups, higher level of Hg was observed in kidney, liver, spleen and even in brain than single Hg administration groups. In addition, Se level in organ tissues increased obviously not only in Se exposure group but also in MeHg exposure group, while the phenomenon was not observed in iHg exposure group. HepG2 cells were employed to investigate Se and Hg interactions in single cell level, similar bioaccumulation behavior of Hg was found between cells and mice organs. Higher level of Hg was observed in cells cultured with Se and Hg medium than cells cultured with single Hg medium. The results are expected to provide new insight to investigate Hg and Se interactions in animal bodies and in-vitro cells.


Assuntos
Terapia a Laser , Mercúrio , Compostos de Metilmercúrio , Selênio , Animais , Fígado , Mercúrio/toxicidade , Compostos de Metilmercúrio/toxicidade , Camundongos , Selênio/toxicidade
2.
Zhongguo Zhong Yao Za Zhi ; 46(18): 4704-4711, 2021 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-34581079

RESUMO

As the main chemical constituents, iridoids are widely distributed within Gentiana, Gentianaceae, with promising bioactivities. Based on the previous work, the transcriptome of G. lhassica, an original plant of Tibetan herb "Jieji Nabao", was sequenced and analyzed in this study, and the transcriptome databases of roots, stems, leaves, and flowers were constructed so as to explore unigenes that may encode the key enzymes in the biosynthetic pathway of iridoids. Then, qRT-PCR was used to validate the relative expression levels of 11 genes named AACT, DXS, MCS, HDS, IDI, GPPS, GES, G10H, 7-DLNGT, 7-DLGT, and SLS in roots, stems, leaves, and flowers. Also, the total contents of gentiopicroside and loganic acid were determined by HPLC, respectively. The results are as follows:(1)a total of 76 486 unigenes with an average length of 852 bp were obtained;(2)335 unigenes were involved in 19 stan-dard secondary metabolism pathways in KEGG database, with phenylpropanoid biosynthesis having the maximum number(75 unigenes), and no isoflavone biosynthetic pathway was annotated;(3)171 unigenes participatedin 27 key enzymes encoding in the biosynthetic pathway of iridoids, and 1-deoxy-D-xylulose-5-phosphate reductoisomerase(DXR) gene was highly expressed;(4)qRT-PCR results were approximately consistent with RNA-Seq data and the relative expression levels of the 11 genes were higher in the aboveground parts(stem, leaf, and flower) than in the underground part(root);(5)the total contents of gentiopicroside and loganic acid were higher in the aboveground parts(stem, leaf, and flower) than in the underground part(root), and the difference was significant. This study provides basic scientific data for accurate species identification, evaluation of germplasm resources, research on secondary pro-duct accumulation of medicinal plants within Gentianaceae, and protection of endangered alpine species.


Assuntos
Gentiana , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Gentiana/genética , Iridoides , Transcriptoma
3.
ACS Appl Mater Interfaces ; 13(36): 43668-43675, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34473482

RESUMO

The efficient recognition of circulating tumor cells (CTCs) with an aptamer probe confers numerous benefits; however, the stability and binding affinity of aptamers are significantly hampered in real biological sample matrices. Inspired by the efficient preying mechanism by multiplex tubing feet and endoskeletons of sea urchins, we engineered a superefficient biomimetic single-CTC recognition platform by conjugating dual-multivalent-aptamers (DMAs) Sgc8 and SYL3C onto AuNPs to form a sea urchin-like nanoprobe (sea urchin-DMA-AuNPs). Aptamers Sgc8 and SYL3C selectively bind with the biomarker proteins PTK7 and EpCAM expressed on the surface of CTCs. CTCs were captured with 100% efficiency, followed by sorting on a specially designed multifunctional microfluidic configuration, integrating a single-CTC separation unit and a hydrodynamic filtrating purification unit. After sorting, background-free analysis of biomarker proteins in single CTCs was undertaken with inductively coupled plasma mass spectrometry by measuring the amount of 197Au isotope in sea urchin-DMA-AuNPs. With respect to a single-aptamer nanoprobe/-interface, the dual-aptamer nanoprobe improves the binding efficiency by more than 200% (Kd < 0.35 nM). The microchip facilitates the recognition of single CTCs with a sorting separation rate of 93.6% at a flow rate of 60 µL min-1, and it exhibits 73.8 ± 5.0% measurement efficiency for single CTCs. The present strategy ensures the manipulation and detection of a single CTC in 100 µL of whole blood within 1 h.

4.
Molecules ; 26(16)2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34443582

RESUMO

Biological imaging is an essential means of disease diagnosis. However, semiconductor quantum dots that are used in bioimaging applications comprise toxic metal elements that are nonbiodegradable, causing serious environmental problems. Herein, we developed a novel ecofriendly solvothermal method that uses ethanol as a solvent and doping with chlorine atoms to prepare highly fluorescent graphene quantum dots (GQDs) from seaweed. The GQDs doped with chlorine atoms exhibit high-intensity white fluorescence. Thus, their preliminary application in bioimaging has been confirmed. In addition, clear cell imaging could be performed at an excitation wavelength of 633 nm.


Assuntos
Cloro/química , Grafite/química , Imagem Molecular/métodos , Pontos Quânticos/química , Alga Marinha/química , Linhagem Celular , Fluorescência
5.
Talanta ; 234: 122618, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34364427

RESUMO

Low-molecular-weight thiols play a central role in preventing oxidative damage caused by reactive oxygen species to maintain a reductive intracellular environment in bacteria. Therefore, targeting thiol-redox homeostasis is considered a promising antimicrobial strategy. Here, we synthesize histidine-stabilized gold nanoclusters (Au NCs), in which the histidine ligand has a weak affinity for gold, thus constructing an effective thiol scavenger by employing metal-thiol depletion chemicals. Au NCs exert excellent antimicrobial effects by consuming thiols and simultaneously causing the accumulation of reactive oxygen species in bacteria, resulting in severe oxidative stress. In a mouse skin wound model infected with ampicillin-resistant Escherichia coli pHSP70-EGFP, a low dose of Au NCs exerts a strong therapeutic effect on bacterial clearance and wound healing, indicating the effectiveness of this antimicrobial strategy for clinical application.


Assuntos
Ouro , Nanopartículas Metálicas , Animais , Antibacterianos/farmacologia , Escherichia coli , Homeostase , Camundongos , Oxirredução , Compostos de Sulfidrila
6.
EMBO J ; 40(18): e108249, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34296442

RESUMO

SARS-CoV-2 is an emerging coronavirus that causes dysfunctions in multiple human cells and tissues. Studies have looked at the entry of SARS-CoV-2 into host cells mediated by the viral spike protein and human receptor ACE2. However, less is known about the cellular immune responses triggered by SARS-CoV-2 viral proteins. Here, we show that the nucleocapsid of SARS-CoV-2 inhibits host pyroptosis by blocking Gasdermin D (GSDMD) cleavage. SARS-CoV-2-infected monocytes show enhanced cellular interleukin-1ß (IL-1ß) expression, but reduced IL-1ß secretion. While SARS-CoV-2 infection promotes activation of the NLRP3 inflammasome and caspase-1, GSDMD cleavage and pyroptosis are inhibited in infected human monocytes. SARS-CoV-2 nucleocapsid protein associates with GSDMD in cells and inhibits GSDMD cleavage in vitro and in vivo. The nucleocapsid binds the GSDMD linker region and hinders GSDMD processing by caspase-1. These insights into how SARS-CoV-2 antagonizes cellular inflammatory responses may open new avenues for treating COVID-19 in the future.


Assuntos
COVID-19/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Nucleocapsídeo/metabolismo , Proteínas de Ligação a Fosfato/metabolismo , Piroptose/fisiologia , SARS-CoV-2/metabolismo , Enzima de Conversão de Angiotensina 2/imunologia , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , COVID-19/imunologia , COVID-19/patologia , COVID-19/virologia , Caspase 1/imunologia , Caspase 1/metabolismo , Células HEK293 , Interações Hospedeiro-Patógeno , Humanos , Inflamassomos/imunologia , Inflamassomos/metabolismo , Interleucina-1beta/imunologia , Interleucina-1beta/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/imunologia , Camundongos , Monócitos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteínas de Ligação a Fosfato/imunologia , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/metabolismo , Células THP-1
7.
Molecules ; 26(13)2021 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-34206960

RESUMO

High-photoluminescence (PL) graphene quantum dots (GQDs) were synthesized by a simple one-pot hydrothermal process, then separated by dialysis bags of different molecular weights. Four separated GQDs of varying sizes were obtained and displayed different PL intensities. With the decreasing size of separated GQDs, the intensity of the emission peak becomes much stronger. Finally, the GQDs of the smallest size revealed the most energetic PL intensity in four separated GQDs. The PL energy of all the separated GQDs shifted slightly, supported by density functional theory calculations.

8.
Int J Mol Sci ; 22(14)2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34298903

RESUMO

Sucrose content is a crucial indicator of quality and flavor in peanut seed, and there is a lack of clarity on the molecular basis of sucrose metabolism in peanut seed. In this context, we performed a comprehensive comparative transcriptome study on the samples collected at seven seed development stages between a high-sucrose content variety (ICG 12625) and a low-sucrose content variety (Zhonghua 10). The transcriptome analysis identified a total of 8334 genes exhibiting significantly different abundances between the high- and low-sucrose varieties. We identified 28 differentially expressed genes (DEGs) involved in sucrose metabolism in peanut and 12 of these encoded sugars will eventually be exported transporters (SWEETs). The remaining 16 genes encoded enzymes, such as cell wall invertase (CWIN), vacuolar invertase (VIN), cytoplasmic invertase (CIN), cytosolic fructose-bisphosphate aldolase (FBA), cytosolic fructose-1,6-bisphosphate phosphatase (FBP), sucrose synthase (SUS), cytosolic phosphoglucose isomerase (PGI), hexokinase (HK), and sucrose-phosphate phosphatase (SPP). The weighted gene co-expression network analysis (WGCNA) identified seven genes encoding key enzymes (CIN, FBA, FBP, HK, and SPP), three SWEET genes, and 90 transcription factors (TFs) showing a high correlation with sucrose content. Furthermore, upon validation, six of these genes were successfully verified as exhibiting higher expression in high-sucrose recombinant inbred lines (RILs). Our study suggested the key roles of the high expression of SWEETs and enzymes in sucrose synthesis making the genotype ICG 12625 sucrose-rich. This study also provided insights into the molecular basis of sucrose metabolism during seed development and facilitated exploring key candidate genes and molecular breeding for sucrose content in peanuts.


Assuntos
Arachis/genética , Arachis/metabolismo , Sacarose/metabolismo , Transcriptoma/genética , Metabolismo dos Carboidratos/genética , Parede Celular/genética , Parede Celular/metabolismo , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas/genética , Glucosiltransferases/genética , Glucosiltransferases/metabolismo , Sementes/genética , Sementes/metabolismo , beta-Frutofuranosidase/genética , beta-Frutofuranosidase/metabolismo
9.
Cell ; 184(13): 3542-3558.e16, 2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34051138

RESUMO

Structural variations (SVs) and gene copy number variations (gCNVs) have contributed to crop evolution, domestication, and improvement. Here, we assembled 31 high-quality genomes of genetically diverse rice accessions. Coupling with two existing assemblies, we developed pan-genome-scale genomic resources including a graph-based genome, providing access to rice genomic variations. Specifically, we discovered 171,072 SVs and 25,549 gCNVs and used an Oryza glaberrima assembly to infer the derived states of SVs in the Oryza sativa population. Our analyses of SV formation mechanisms, impacts on gene expression, and distributions among subpopulations illustrate the utility of these resources for understanding how SVs and gCNVs shaped rice environmental adaptation and domestication. Our graph-based genome enabled genome-wide association study (GWAS)-based identification of phenotype-associated genetic variations undetectable when using only SNPs and a single reference assembly. Our work provides rich population-scale resources paired with easy-to-access tools to facilitate rice breeding as well as plant functional genomics and evolutionary biology research.

10.
Plant Biotechnol J ; 19(8): 1644-1657, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33740293

RESUMO

Circadian clock, an endogenous time-setting mechanism, allows plants to adapt to unstable photoperiod conditions and induces flowering with proper timing. In Arabidopsis, the central clock oscillator was formed by a series of interlocked transcriptional feedback loops, but little is known in rice so far. By MutMap technique, we identified the candidate gene OsLHY from a later flowering mutant lem1 and further confirmed it through genetic complementation, RNA interference knockdown, and CRISPR/Cas9-knockout. Global transcriptome profiling and expression analyses revealed that OsLHY might be a vital circadian rhythm component. Interestingly, oslhy flowered later under ≥12 h day length but headed earlier under ≤11 h day length. qRT-PCR results exhibited that OsLHY might function through OsGI-Hd1 pathway. Subsequent one-hybrid assays in yeast, DNA affinity purification qPCR, and electrophoretic mobility shift assays confirmed OsLHY could directly bind to the CBS element in OsGI promoter. Moreover, the critical day length (CDL) for function reversal of OsLHY in oslhy (11-12 h) was prolonged in the double mutant oslhy osgi (about 13.5 h), indicating that the CDL set by OsLHY was OsGI dependent. Additionally, the dual function of OsLHY entirely relied on Hd1, as the double mutant oslhy hd1 showed the same heading date with hd1 under about 11.5, 13.5, and 14 h day lengths. Together, OsLHY could fine-tune the CDL by directly regulating OsGI, and Hd1 acts as the final effector of CDL downstream of OsLHY. Our study illustrates a new regulatory mechanism between the circadian clock and photoperiodic flowering.


Assuntos
Oryza , Fotoperíodo , Ritmo Circadiano/genética , Flores/genética , Flores/metabolismo , Regulação da Expressão Gênica de Plantas , Oryza/genética , Oryza/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
11.
Nat Plants ; 7(2): 129-136, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33594262

RESUMO

MicroRNA168 (miR168) is a key miRNA that targets Argonaute1 (AGO1), a major component of the RNA-induced silencing complex1,2. Previously, we reported that miR168 expression was responsive to infection by Magnaporthe oryzae, the causal agent of rice blast disease3. However, how miR168 regulates immunity to rice blast and whether it affects rice development remains unclear. Here, we report our discovery that the suppression of miR168 by a target mimic (MIM168) not only improves grain yield and shortens flowering time in rice but also enhances immunity to M. oryzae. These results were validated through repeated tests in rice fields in the absence and presence of rice blast pressure. We found that the miR168-AGO1 module regulates miR535 to improve yield by increasing panicle number, miR164 to reduce flowering time, and miR1320 and miR164 to enhance immunity. Our discovery demonstrates that changes in a single miRNA enhance the expression of multiple agronomically important traits.


Assuntos
Magnoliopsida/genética , MicroRNAs/genética , Oryza/genética , Melhoramento Vegetal/métodos , Imunidade Vegetal/genética , Plantas Geneticamente Modificadas/genética , RNA de Plantas/genética , China , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Supressão Genética
12.
Sci Total Environ ; 764: 144388, 2021 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-33387764

RESUMO

Selective adsorption via the size matching effect is one of the most effective strategies for separating and analyzing low levels of organic molecules. Herein, multicomponent covalent organic frameworks (MC-COFs) with tunable pore sizes are constructed by using one knot (1,3,5-triformylphloroglucinol, Tp) and two organic linkers (p-phenylenediamine, Pa; benzidine, BD). The pore sizes of the MC-COFs composed of TpPaBDX (X = [BD]/([Pa] + [BD]) × 100 = 0, 25, 50, 75, and 100) range from 0.5-1.5 to 0.5-2.2 nm due to variations in the initial organic linker ratios. When coupling TpPaBDX-based solid-phase microextraction (SPME) with constant flow desorption ionization mass spectrometry (CFDI-MS), these MC-COFs feature better selective adsorption performance for tetrabromobisphenol A (TBBPA) derivatives than TpPa with a smaller pore size, TpBD with a larger pore size and even some commercial fibers (e.g., polydimethylsiloxane/divinylbenzene (PDMS/DVB)-, polyacrylate (PA)- and PDMS-coated fibers). The improved method involving MC-COF TpPaBD50 also presents favorable stability with relative standard deviations (RSD, 1 µg L-1) for single fibers of 5.5-7.9% (n = 7) and fiber-to-fiber of 6.6-7.8% (n = 7). Due to the decreased limits of detection and quantification (0.5-12 and 1.6-40 ng L-1), and reduced separation and detection time (7 min), ultratrace levels of TBBPA derivatives in real water samples are successfully detected. The proposed method shows great potential for the rapid tracing of the distribution, transportation and transformation of TBBPA derivatives to better understand their ecotoxicological effects in environmental media.

13.
J Hazard Mater ; 411: 125021, 2021 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-33476910

RESUMO

A novel dual functional composite (MOFL-TpBD) was prepared through solvothermal methods, with excellent Pb2+ ions separation and stable 2,4,6-Trinitrophenol (TNP) fluorescence detection performance. MOFL-TpBD was characterized by FTIR, XRD, XPS, SEM and TGA et al. The prepared material was used to extract Pb2+ ions, with an adsorption capacity of 21.74 mg g-1 calculated by Langmuir isotherm model. The limit of detection was 0.32 µg L-1, along with a linear range from 0.7 to 12 µg L-1 and a precision of 5.4% (1 µg L-1, n = 9), respectively, where MOFL-TpBD was adopted as adsorbent for Pb2+ ions preconcentration. The practical samples and reference water sample were measured by the provided method, with the satisfactory recoveries (91-110%) and reliable analytical results. MOFL-TpBD was capable of fluorescent sensing of TNP, with a linear range from 0.01 to 1 mM and a limit of detection of 3.52 µM, respectively, and a precision of 3.29% was obtained (0.2 mM, n = 11). Meanwhile, the recoveries ranged from 91% to 108% in analysis of TNP for the practical samples. The designed material provided a potential candidate material for the detection of heavy metal ions and explosives in environmental water samples.

14.
Microvasc Res ; 133: 104092, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33007315

RESUMO

The in vitro reconstruction of the microvascular network model provides a reproducible platform for hemodynamic study with great biological relevance. In the present study, microvascular models with different parametric features were designed under the guidance of Murray's law and derived from representative natural vascular network topography in vivo. Computational fluid dynamics (CFD) was used to numerically simulate blood velocity distributions inside of the designed microvasculature models. Full-field blood flow in the vascular network was visualized in vivo using a laser speckle contrast imaging (LSCI) system, from which the measured relative velocity was compared with CFD computed flow distribution. The results have shown that, in comparison with the simplified flow patterns obtained from idealized geometries, the irregular vascular topography is expected to lead to nonuniform and poor regional blood velocity distribution. The velocity distribution acquired by in vivo LSCI experiment is in good agreement with that of numerical simulation, indicating the technical feasibility of using biomimetic microchannels as a reasonable approximation of the microcirculatory flow conditions. This study provides a new paradigm that can be well suited to the study of microvascular blood flow properties and can further expand to mimic other in-vivo scenarios for accurately recapitulating the physical and hemodynamic environment of the microcirculation.


Assuntos
Orelha Externa/irrigação sanguínea , Imagem de Contraste de Manchas a Laser , Microcirculação , Microvasos/diagnóstico por imagem , Microvasos/fisiologia , Modelos Cardiovasculares , Animais , Velocidade do Fluxo Sanguíneo , Simulação por Computador , Hidrodinâmica , Camundongos Endogâmicos ICR
15.
ACS Appl Mater Interfaces ; 12(49): 55453-55459, 2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-33231420

RESUMO

The high tunability of metal-organic frameworks (MOFs) provides attractive flexibility to tailor their surface properties for practical demands. Here we report the regulation of the surface properties (hydrophilicity and charge characteristics) of Co-based MOFs by exploiting different organic building units and tailor them as efficient adsorbents for specific protein enrichment. Compared with the pristine Co-based MOF (Co-MOF) and the aminated MOF (Co-MOF-NH2), the MOF decorated with abundant hydroxyl groups (Co-MOF-OH) exhibits superior adsorption selectivity and enriched efficiency toward immunoglobulin G (IgG) in the physiological state (pH 7.4) by taking advantage of the favorable hydrogen-bonding interactions and electrostatic force between IgG and Co-MOF-OH. The enrichment factor for IgG is high, up to 97.7 for enriching IgG from the IgG/human serum albumin mixture with a mass ratio of 1:50, and circular dichroism indicates that the enrichment process poses no influence on the protein structure. Moreover, Co-MOF-OH proves its practicability in complex biological samples by the selective extraction of IgG from complex human serum samples.


Assuntos
Cobalto/química , Imunoglobulina G/isolamento & purificação , Estruturas Metalorgânicas/química , Adsorção , Dicroísmo Circular , Humanos , Ligação de Hidrogênio , Concentração de Íons de Hidrogênio , Imunoglobulina G/química , Albumina Sérica/química , Eletricidade Estática , Propriedades de Superfície
16.
Sci Adv ; 6(40)2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33008913

RESUMO

Quantum dots have innate advantages as the key component of optoelectronic devices. For white light-emitting diodes (WLEDs), the modulation of the spectrum and color of the device often involves various quantum dots of different emission wavelengths. Here, we fabricate a series of carbon quantum dots (CQDs) through a scalable acid reagent engineering strategy. The growing electron-withdrawing groups on the surface of CQDs that originated from acid reagents boost their photoluminescence wavelength red shift and raise their particle sizes, elucidating the quantum size effect. These CQDs emit bright and remarkably stable full-color fluorescence ranging from blue to red light and even white light. Full-color emissive polymer films and all types of high-color rendering index WLEDs are synthesized by mixing multiple kinds of CQDs in appropriate ratios. The universal electron-donating/withdrawing group engineering approach for synthesizing tunable emissive CQDs will facilitate the progress of carbon-based luminescent materials for manufacturing forward-looking films and devices.

17.
Biomed Microdevices ; 22(4): 70, 2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-32960346

RESUMO

The advent of microfluidic technologies has enabled a better recapitulation of in vitro tumor model with higher biological relevance over conventional monolayer assays. This work built upon a microfluidic system that supported the spontaneous aggregate formation of tumoral cells under flow-induced dynamic physical forces in a confined microchamber without additional matrix materials. Our findings indicated that fluidic streams significantly modulated the biological and architectural features of human breast adenocarcinoma cell (MCF-7), human hepatocarcinoma cell (HepG2), and human cervix adenocarcinoma cell (HeLa) with cell-type-dependent variation. The microfluidic platform was further integrated with a fluorescence detection and imaging system, allowing for non-invasive monitoring of cellular accumulation and spatial distribution of a chemotherapeutic agent, doxorubicin (DOX). The cytotoxic effects of DOX of various concentrations were determined and compared in MCF-7 cells in conventional two-dimensional (2D) static and microfluidic culture conditions. Dose-dependent response to DOX was noticed in both cultures, whereas tumor micronodules grown in microfluidic devices demonstrated significantly lower sensitivity to DOX at increased concentration. Our platform owns promising potentials as a universal modality for bridging traditional 2D cell cultures and in vivo experimentation for preclinical anticancer drug screening.

18.
Nat Microbiol ; 5(12): 1565-1575, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32958858

RESUMO

Many pathogenic fungi depend on the development of specialized infection structures called appressoria to invade their hosts and cause disease. Impairing the function of fungal infection structures therefore provides a potential means by which diseases could be prevented. In spite of this extraordinary potential, however, relatively few anti-penetrant drugs have been developed to control fungal diseases, of either plants or animals. In the present study, we report the identification of compounds that act specifically to prevent fungal infection. We found that the organization of septin GTPases, which are essential for appressorium-mediated infection in the rice blast fungus Magnaporthe oryzae, requires very-long-chain fatty acids (VLCFAs), which act as mediators of septin organization at membrane interfaces. VLCFAs promote septin recruitment to curved plasma membranes and depletion of VLCFAs prevents septin assembly and host penetration by M. oryzae. We observed that VLCFA biosynthesis inhibitors not only prevent rice blast disease, but also show effective, broad-spectrum fungicidal activity against a wide range of fungal pathogens of maize, wheat and locusts, without affecting their respective hosts. Our findings reveal a mechanism underlying septin-mediated infection structure formation in fungi and provide a class of fungicides to control diverse diseases of plants and animals.


Assuntos
Inibidores Enzimáticos/farmacologia , Proteínas Fúngicas/antagonistas & inibidores , Fungos/efeitos dos fármacos , Fungicidas Industriais/farmacologia , Doenças das Plantas/microbiologia , Septinas/antagonistas & inibidores , Ascomicetos/efeitos dos fármacos , Ascomicetos/enzimologia , Ascomicetos/genética , Ácidos Graxos/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Fungos/enzimologia , Fungos/genética , Oryza/microbiologia , Septinas/genética , Septinas/metabolismo
19.
Plant Sci ; 298: 110585, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32771145

RESUMO

Leaf color is directly associated with plant photosynthesis. Here, we have isolated and identified a spontaneous rice mutant named yd1 that has yellowish leaves and dwarf stature. Map-based cloning reveals that YD1 encodes a previously reported kinesin protein from the kinesin-4 subfamily, BC12/GDD1. Arginine-328 is replaced by leucine in yd1, BC12328Leu. YD1 is mainly expressed in leaves and is involved in chlorophyll (Chl) synthesis. The yd1 mutant had less Chl and a reduced and disordered thylakoid ultrastructure. In yd1 plants, Chl biosynthesis and photosynthesis associated gene expression was decreased and Chl degradation gene expression was increased, thereby leading to a reduced photosynthesis rate and grain yield. In this study we reveal that the novel BC12328Leu allele of BC12 modulated plant leaf color in yd1 plants, which has not been previously reported in studies of BC12/GDD1/MTD1/SRG1. Gene knockout results indicated that YD1 regulates leaf color in the indica rice background, but not in the japonica rice background. Our study provides new insights into molecular regulation of rice growth by BC12/GDD1 in different genetic backgrounds.


Assuntos
Oryza/fisiologia , Pigmentos Biológicos/fisiologia , Folhas de Planta/fisiologia , Proteínas de Plantas/genética , Alelos , Sequência de Aminoácidos , Cor , Oryza/genética , Pigmentos Biológicos/genética , Folhas de Planta/genética , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Alinhamento de Sequência
20.
ACS Omega ; 5(23): 13548-13556, 2020 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-32566819

RESUMO

With the development of the environment and human society, the removal of metal ions and dyes in wastewater treatment remains an urgent problem to solve. In this work, two biomass carbon adsorbents were synthesized by a KOH activation and carbonization route using sorghum stem and root as carbon precursors. In comparison with the samples without KOH activation, the pore structure of the KOH-activated carbon has been dramatically improved. The findings show that the specific surface areas of the adsorbents by sorghum stem (S1) and sorghum root (R1) were 948.6 and 168.1 m2 g-1, respectively. Meanwhile, the abundant OH- and COO- groups on the surface of these adsorbents endow them with negative polarity, thereby exhibiting excellent adsorption performance for removing methylene blue (MB) and Pb(II) from wastewater. The adsorption amount and removal rate of S1 were 98.1 mg g-1 and 98.08%, respectively, for MB, whereas those of R1 were 197.6 mg g-1 and 98.82% for the Pb(II) ion, respectively. Our findings offer an invaluable insight into designing and synthesizing a highly efficient sustainable adsorbent to remove MB and Pb(II) based on biomass agricultural waste.

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