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1.
Curr Issues Mol Biol ; 46(6): 6186-6198, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38921040

RESUMO

The family Scolopacidae presents a valuable subject for evolutionary research; however, molecular studies of Scolopacidae are still relatively understudied, and the phylogenetic relationships of certain species remain unclear. In this study, we sequenced and obtained complete mitochondrial DNA (mtDNA) from Actitis hypoleucos and partial mtDNA from Numenius arquata, Limosa limosa, and Limnodromus semipalmatus. The complete mtDNA contained 13 protein-coding genes (PCGs), two ribosomal RNA genes, 22 tRNA genes, and a control region. Scolopacidae contained three types of start codons and five types of stop codons (including one incomplete stop codon, T--). In 13 protein-coding genes, average uncorrected pairwise distances (Aupd) revealed that ATP8 was the least conserved while COX3 had the lowest evolutionary rate. The ratio of Ka/Ks suggested that all PCGs were under purifying selection. Using two methods (maximum likelihood and Bayesian inference) to analyze the phylogenetic relationships of the family Scolopacidae, it was found that the genera Xenus and Actitis were clustered into another sister group, while the genus Phalaropus is more closely related to the genus Tringa. The genera Limnodromus, Gallinago, and Scolopax form a monophyletic group. This study improves our understanding of the evolutionary patterns and phylogenetic relationships of the family Scolopacidae.

2.
J Transl Med ; 22(1): 436, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38720350

RESUMO

BACKGROUND: Subarachnoid hemorrhage (SAH) represents a form of cerebrovascular event characterized by a notable mortality and morbidity rate. Fibroblast growth factor 21 (FGF21), a versatile hormone predominantly synthesized by the hepatic tissue, has emerged as a promising neuroprotective agent. Nevertheless, the precise impacts and underlying mechanisms of FGF21 in the context of SAH remain enigmatic. METHODS: To elucidate the role of FGF21 in inhibiting the microglial cGAS-STING pathway and providing protection against SAH-induced cerebral injury, a series of cellular and molecular techniques, including western blot analysis, real-time polymerase chain reaction, immunohistochemistry, RNA sequencing, and behavioral assays, were employed. RESULTS: Administration of recombinant fibroblast growth factor 21 (rFGF21) effectively mitigated neural apoptosis, improved cerebral edema, and attenuated neurological impairments post-SAH. Transcriptomic analysis revealed that SAH triggered the upregulation of numerous genes linked to innate immunity, particularly those involved in the type I interferon (IFN-I) pathway and microglial function, which were notably suppressed upon adjunctive rFGF21 treatment. Mechanistically, rFGF21 intervention facilitated mitophagy in an AMP-activated protein kinase (AMPK)-dependent manner, thereby preventing mitochondrial DNA (mtDNA) release into the cytoplasm and dampening the activation of the DNA-sensing cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) signaling pathway. Conditional knockout of STING in microglia markedly ameliorated the inflammatory response and mitigated secondary brain injuries post-SAH. CONCLUSION: Our results present the initial evidence that FGF21 confers a protective effect against neuroinflammation-associated brain damage subsequent to SAH. Mechanistically, we have elucidated a novel pathway by which FGF21 exerts this neuroprotection through inhibition of the cGAS-STING signaling cascade.


Assuntos
Fatores de Crescimento de Fibroblastos , Proteínas de Membrana , Camundongos Endogâmicos C57BL , Mitofagia , Doenças Neuroinflamatórias , Nucleotidiltransferases , Transdução de Sinais , Hemorragia Subaracnóidea , Animais , Proteínas de Membrana/metabolismo , Fatores de Crescimento de Fibroblastos/metabolismo , Hemorragia Subaracnóidea/complicações , Hemorragia Subaracnóidea/metabolismo , Hemorragia Subaracnóidea/patologia , Doenças Neuroinflamatórias/metabolismo , Doenças Neuroinflamatórias/etiologia , Mitofagia/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Nucleotidiltransferases/metabolismo , Masculino , Camundongos , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Microglia/metabolismo , Microglia/patologia , Microglia/efeitos dos fármacos , Apoptose/efeitos dos fármacos
3.
J Med Virol ; 96(6): e29687, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38783821

RESUMO

Pregnancy heightens susceptibility to influenza A virus (IAV) infection, thereby increasing the risk of severe pneumonia and maternal mortality. It also raises the chances of adverse outcomes in offspring, such as fetal growth restriction, preterm birth, miscarriage, and stillbirth in offsprings. However, the underlying mechanisms behind these effects remain largely unknown. Syncytiotrophoblast cells, crucial in forming the placental barrier, nutrient exchange and hormone secretion, have not been extensively studied for their responses to IAV. In our experiment, we used Forskolin-treated BeWo cells to mimic syncytiotrophoblast cells in vitro, and infected them with H1N1, H5N1 and H7N9 virus stains. Our results showed that syncytiotrophoblast cells, with their higher intensity of sialic acid receptors, strongly support IAV infection and replication. Notably, high-dose viral infection and prolonged exposure resulted in a significant decrease in fusion index, as well as gene and protein expression levels associated with trophoblast differentiation, ß-human chorionic gonadotropin secretion, estrogen and progesterone biosynthesis, and nutrient transport. In pregnant BALB/c mice infected with the H1N1 virus, we observed significant decreases in trophoblast differentiation and hormone secretion gene expression levels. IAV infection also resulted in preterm labor, fetal growth restriction, and increased maternal and fetal morbidity and mortality. Our findings indicate that IAV infection in syncytiotrophoblastic cells can result in adverse pregnancy outcomes by altering trophoblast differentiation, suppressing of ß-hCG secretion, and disrupting placental barrier function.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Camundongos Endogâmicos BALB C , Infecções por Orthomyxoviridae , Resultado da Gravidez , Trofoblastos , Feminino , Trofoblastos/virologia , Gravidez , Animais , Humanos , Vírus da Influenza A Subtipo H1N1/fisiologia , Camundongos , Infecções por Orthomyxoviridae/virologia , Influenza Humana/virologia , Linhagem Celular , Virus da Influenza A Subtipo H5N1/fisiologia , Subtipo H7N9 do Vírus da Influenza A/fisiologia , Subtipo H7N9 do Vírus da Influenza A/patogenicidade , Complicações Infecciosas na Gravidez/virologia , Placenta/virologia , Replicação Viral
4.
Environ Sci Technol ; 58(4): 1934-1943, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38180751

RESUMO

Antimony (Sb) biomethylation is an important but uninformed process in Sb biogeochemical cycling. Methylated Sb species have been widely detected in the environment, but the gene and enzyme for Sb methylation remain unknown. Here, we found that arsenite S-adenosylmethionine methyltransferase (ArsM) is able to catalyze Sb(III) methylation. The stepwise methylation by ArsM forms mono-, di-, and trimethylated Sb species. Sb(III) is readily coordinated with glutathione, forming the preferred ArsM substrate which is anchored on three conserved cysteines. Overexpressing arsM in Escherichia coli AW3110 conferred resistance to Sb(III) by converting intracellular Sb(III) into gaseous methylated species, serving as a detoxification process. Methylated Sb species were detected in paddy soil cultures, and phylogenetic analysis of ArsM showed its great diversity in ecosystems, suggesting a high metabolic potential for Sb(III) methylation in the environment. This study shows an undiscovered microbial process methylating aqueous Sb(III) into the gaseous phase, mobilizing Sb on a regional and even global scale as a re-emerging contaminant.


Assuntos
Arsênio , Arsenitos , Nostoc , Arsenitos/metabolismo , S-Adenosilmetionina/metabolismo , Antimônio , Arsênio/química , Nostoc/metabolismo , Ecossistema , Filogenia , Metiltransferases/química , Metiltransferases/genética , Metiltransferases/metabolismo
5.
Anal Chem ; 95(34): 12956-12963, 2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37583286

RESUMO

With the widespread use of uranium in the nuclear industry, achieving rapid and sensitive detection of uranium contaminants is critical for reducing environmental pollution. Surface-enhanced Raman scattering (SERS), with its high sensitivity and unique fingerprint properties, has been used for the analysis of uranyl. However, the weak affinity of Au for uranyl remains a challenge in the development of spherical Au-based SERS substrates. The metal-organic framework (MOF) material ZIF-8 exhibits excellent adsorption capacity for uranyl and could overcome this limitation. In this study, ZIF-8 porous structures were modified on a magnetic SERS substrate, Fe3O4@SiO2@Au (FA), for the rapid and sensitive detection and analysis of the uranyl species. Uranyl was adsorbed by ZIF-8, allowing ready access to the hot spots in the interstices of Au nanoparticles (AuNPs). Symmetrically stretched vibrating bonds of O═U═O were detected at 829 cm-1 as the characteristic peak of uranyl by surface plasmon resonance between the AuNPs. The ZIF-8 coating had minimal influence on target detection as the detection limit for 4-MPY was only half an order of magnitude lower than before modification. The enhancement factor for uranyl reached 106. The substrate showed excellent sensing performance in a neutral or alkaline environment. It was used to detect uranyl in tap water and river water; rapid separation of the species from the water samples was achieved using an external magnet to extract radioactive waste. The proposed substrate offers a route for monitoring and detecting uranyl contamination and an approach for achieving rapid on-site detection, providing a promising application for environmental contaminant detection.

6.
Bioorg Med Chem ; 83: 117213, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36934526

RESUMO

The anti-cancer peptides emerged as new weapons for cancer therapy due to their potent toxicity toward various cancer cells. However, their therapeutic promise is often limited by non-specific toxicity to normal cells. How to improve peptides' selectivity to cancer cells is always a matter to solve. In this manuscript, we designed a sulfonium tethered lytic peptide conjugated with a HDAC inhibitor to improve the selectivity of cancer cells. The sulfonium tethered lytic peptide with improved hydrophilicity and positive charge showed reduced toxicity to both cancer cells and normal cells. When conjugated with the HDAC inhibitor, this peptide showed increased toxicity to cancer cells. Besides, the stabilized peptide HDAC conjugate showed better serum stability than the linear peptide conjugate. For cellular function, the stabilized peptide conjugate could induce cancer cell apoptosis, cell cycle arrest, and influence multiple signal pathways through transcriptome analysis. This design may provide an alternative approach for the development of safe and effective anti-cancer drugs.


Assuntos
Antineoplásicos , Neoplasias , Humanos , Inibidores de Histona Desacetilases/farmacologia , Peptídeos/metabolismo , Neoplasias/tratamento farmacológico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose , Linhagem Celular Tumoral
7.
Macromol Rapid Commun ; 44(23): e2300325, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37566735

RESUMO

Biocompatible chitosan-based hydrogels have attracted extensive attention in wound dressing due to their human skin-like tissue characteristics. However, it is a crucial challenge to fabricate chitosan-based hydrogels with versatile properties, including flexibility, stretchability, adhesivity, and antibacterial activity. In this work, a kind of chitosan-based hydrogels with integrated functionalities are facilely prepared by solution polymerization of acrylamide (AAm) and sodium p-styrene sulfonate (SS) in the presence of quaternized carboxymethyl chitosan (QCMCS). Due to the dual cross-linking between QCMCS and P(AAm-co-SS), the optimized QCMCS/P(AAm-co-SS) hydrogel exhibits tough mechanical properties (0.767 MPa tensile stress and 1100% fracture strain) and moderate tissue adhesion (11.4 kPa). Moreover, biological evaluation in vitro illustrated that as-prepared hydrogel possesses satisfactory biocompatibility, hemocompatibility, and excellent antibacterial ability (against S. aureus and E. coli are 98.8% and 97.3%, respectively). Then, the hydrogels are tested in a rat model for bacterial infection incision in vivo, and the results show that they can significantly accelerate epidermal regeneration and wound closure. This is due to their ability to reduce the inflammatory response, promote the formation of collagen deposition and granulation tissue. The proposed chitosan-based antibacterial hydrogels have the potential to be a highly effective wound dressing in clinical wound healing.


Assuntos
Quitosana , Ratos , Animais , Humanos , Hidrogéis/farmacologia , Adesivos , Escherichia coli , Staphylococcus aureus , Antibacterianos/farmacologia , Bandagens
8.
Ecotoxicol Environ Saf ; 249: 114405, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36508807

RESUMO

Atmosphere aerosols have significant impact on human health and the environment. Aerosol particles have a number of characteristics that influence their health and environmental effects, including their size, shape, and chemical composition. A great deal of difficulty is associated with quantifying and identifying atmospheric aerosols because these parameters are highly variable on a spatial and temporal scale. An important component of understanding aerosol fate is Raman Spectroscopy (RS), which is capable of resolving chemical compositions of individual particles. This review presented strategic techniques, especially RS methods for characterizing atmospheric aerosols. The nature and properties of atmospheric aerosols and their influence on environment and human health were briefly described. Analytical methodologies that offer insight into the chemistry and multidimensional properties of aerosols were discussed. In addition, perspectives for practical applications of atmospheric aerosols using RS are featured.


Assuntos
Clima , Análise Espectral Raman , Humanos , Análise Espectral Raman/métodos , Atmosfera/química , Aerossóis/química
9.
Int J Mol Sci ; 24(19)2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37834145

RESUMO

Chlorophyll is an indispensable photoreceptor in plant photosynthesis. Its anabolic imbalance is detrimental to individual growth and development. As an essential epigenetic modification, DNA methylation can induce phenotypic variations, such as leaf color transformation, by regulating gene expression. Albino line XN1376B is a natural mutation of winter wheat cultivar XN1376; however, the regulatory mechanism of its albinism is still unclear. In this study, we found that low temperatures induced albinism in XN1376B. The number of chloroplasts decreased as the phenomenon of bleaching intensified and the fence tissue and sponge tissue slowly dissolved. We identified six distinct TaPOR (protochlorophyllide oxidoreductase) genes in the wheat genome, and TaPOR2D was deemed to be related to the phenomenon of albinism based on the expression in different color leaves (green leaves, white leaves and returned green leaves) and the analysis of promoters' cis-acting elements. TaPOR2D was localized to chloroplasts. TaPOR2D overexpression (TaPOR2D-OE) enhanced the chlorophyll significantly in Arabidopsis, especially at two weeks; the amount of chlorophyll was 6.46 mg/L higher than in WT. The methylation rate of the TaPOR2D promoter in low-temperature albino leaves is as high as 93%, whereas there was no methylation in green leaves. Correspondingly, three DNA methyltransferase genes (TaMET1, TaDRM and TaCMT) were up-regulated in white leaves. Our study clarified that the expression of TaPOR2D is associated with its promoter methylation at a low temperature; it affects the level of chlorophyll accumulation, which probably causes the abnormal development of plant chloroplasts in albino wheat XN1376B. The results provide a theoretical basis for in-depth analysis of the regulation of development of plant chloroplasts and color variation in wheat XN1376B leaves.


Assuntos
Albinismo , Arabidopsis , Clorofila/metabolismo , Triticum/metabolismo , Temperatura , Fotossíntese/genética , Metilação de DNA , Arabidopsis/metabolismo , Albinismo/genética , Albinismo/metabolismo , Folhas de Planta/metabolismo
10.
Analyst ; 147(2): 223-229, 2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-34877945

RESUMO

Imaging biomolecules within a single bacterial cell is crucial for understanding cellular genetic mechanisms. Herein, we exploited a surface-enhanced Raman spectroscopy (SERS) imaging strategy for single cell analysis. Cellular biosynthesized Ag nanoparticles (NPs) provided the necessary enhancement for SERS imaging. Multiple complementary techniques, including high-resolution transmission electron microscopy (HR-TEM), high-angle annular dark-field (HAADF)-scanning transmission electron microscopy (STEM), and energy-dispersive X-ray spectroscopy (EDX), were used to characterize the biogenic Ag NPs in cells. Three-dimensional SERS imaging maps displayed spectral information of biomolecules within the single cell. The multivariate curve resolution (MCR) model and principal component analysis (PCA) model were used to analyze the cellular SERS imaging maps. The MCR model, with a specific constraint of non-negativity, resulted in meaningful identification of biomolecules associated with Ag reduction. Focusing on the molecular level reveals that Pantoea sp. IMH utilizes several mechanisms to synthesize Ag NPs, including cytoplasm reduction by glucose or nicotinamide adenine dinucleotide (NADH)-dependent reductase, and extracellular reduction by an electron transfer chain containing quinone and cytochrome C. Our results shed new light on the Ag NP biosynthesis mechanism and single cell Raman analysis.


Assuntos
Nanopartículas Metálicas , Análise Espectral Raman , Imageamento Tridimensional , Microscopia Eletrônica de Transmissão , Prata
11.
J Fluoresc ; 32(4): 1405-1412, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35438370

RESUMO

A turn-on fluorescent sensor based on CdTe quantum dots (QDs) is designed for highly sensitive and selective ascorbic acid (AA) detection. CdTe shows a strong emission centered at 578 nm. When assembled with poly(sodium 4-styrenesulfonate) (PSS) and methyl viologen (Mv2+) through electrostatic interaction, the emission is found to be effectively quenched. In the presence of AA, Mv2+ is reduced to Mv+, making the fluorescence of CdTe QDs restored. Under the optimal conditions, the proposed AA sensing method shows a linear proportional response from 0.8 µM to 20 µM, with the detecting limit as low as 50 nM. The developed method was successfully applied in the analysis of AA in human serum samples and cell lysates with satisfactory results.


Assuntos
Compostos de Cádmio , Pontos Quânticos , Ácido Ascórbico , Fluorescência , Humanos , Limite de Detecção , Oxirredução , Paraquat , Espectrometria de Fluorescência/métodos , Telúrio
12.
Bull Environ Contam Toxicol ; 109(6): 1043-1050, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36239766

RESUMO

In this study, exposure experiments were conducted to assess the effects of polystyrene nanoparticles (PS) and amine-modified polystyrene nanoparticles (APS) at environmental concentrations (1, 10, and 100 µg L- 1) on two fungal species (Geotrichum candidum and Aspergillus niger), isolated from leaf litter in streams, concerning their growth and metabolic activity. Results showed that PS at 1 and 10 µg L- 1 have hormesis effects on G. candidum growth. Compared with G. candidum, A. niger had higher sensitivity to nanoplastic exposure. Besides, the peroxidase and cellobiohydrolase activities of A. niger were significantly inhibited by nanoplastics (except 1 µg L- 1 PS), which would weaken its metabolic activity in carbon cycling. These results provided a new thought on how the growth and functions of aquatic fungi cope with the stress induced by nanoplastics. Overall, the study provided evidence for the different responses of aquatic fungi to nanoplastics in streams.


Assuntos
Aspergillus niger , Microplásticos , Poliestirenos/toxicidade , Geotrichum/metabolismo
13.
J Environ Sci (China) ; 118: 1-13, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35305757

RESUMO

Fine particles associated with haze pollution threaten the health of over 400 million people in China. Owing to excellent non-destructive fingerprint recognition characteristics, Raman and surface-enhanced Raman scattering (SERS) are often used to analyze the composition of fine particles to determine their physical and chemical properties as well as reaction mechanisms. However, there is no comprehensive Raman spectral library of fine particles. Furthermore, various studies that used SERS for fine-particle composition analysis showed that the uniqueness of the SERS substrates and different excitation wavelengths can produce a different spectrum for the same fine-particle component. To overcome this limitation, we conducted SERS experiments with a portable Raman spectrometer using two common SERS substrates (silver (Ag) foil and gold nanoparticles (Au NPs)) and a 785 nm laser. Herein, we introduced three main particle component types (sulfate-nitrate-ammonium (SNA), organic material, and soot) with a total of 39 chemical substances. We scanned the solid Raman, liquid Raman, and SERS spectra of these substances and constructed a fine-particle reference library containing 105 spectra. Spectral results indicated that for soot and SNA, the differences in characteristic peaks mainly originated from the solid-liquid phase transition; Ag foil had little effect on this difference, while the Au NPs caused a significant red shift in the peak positions of polycyclic aromatic hydrocarbons. Moreover, with various characteristic peak positions in the three types of spectra, we could quickly and correctly distinguish substances. We hope that this spectral library will aid in the future identification of fine particles.


Assuntos
Nanopartículas Metálicas , Análise Espectral Raman , Ouro/química , Humanos , Nanopartículas Metálicas/química , Tamanho da Partícula , Prata/química , Análise Espectral Raman/métodos
14.
Biochem Biophys Res Commun ; 551: 38-45, 2021 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-33714758

RESUMO

Isocitrate dehydrogenase 1 (IDH1) mutant R132H, promoting the oncometabolite D-2-hydroxyglutarate (D2HG), is a driver mutation and an emerging therapeutic target in glioma. This study identified a novel mutant IDH1 inhibitor, WM17, by virtual screening and enzymatic confirmation. It could bind to and increase mutant IDH1 protein's thermostability in both endogenous heterozygous cells and exogenous overexpressed cells. Consequently, WM17 reversed the accumulation of D2HG and histone hypermethylation in IDH1 mutated cells. Finally, we concluded that WM17 significantly inhibited cell migration in IDH1 mutated glioma cells, although it has no apparent effect on cell proliferation. Further studies are guaranteed toward the development of WM17 as a therapeutic agent for IDH1 mutated glioma.


Assuntos
Glioma/tratamento farmacológico , Isocitrato Desidrogenase/antagonistas & inibidores , Isocitrato Desidrogenase/genética , Proteínas Mutantes/antagonistas & inibidores , Mutação , Benzenoacetamidas/farmacologia , Caderinas/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Estabilidade Enzimática/efeitos dos fármacos , Glioma/enzimologia , Glioma/genética , Glioma/patologia , Histonas/metabolismo , Humanos , Imidazóis/farmacologia , Metilação/efeitos dos fármacos , Modelos Moleculares , Terapia de Alvo Molecular , Proteínas Mutantes/genética , Ligação Proteica
15.
Acta Pharmacol Sin ; 42(11): 1875-1887, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33608672

RESUMO

RAS-driven colorectal cancer relies on glucose metabolism to support uncontrolled growth. However, monotherapy with glycolysis inhibitors like 2-deoxy-D-glucose causes limited effectiveness. Recent studies suggest that anti-tumor effects of glycolysis inhibition could be improved by combination treatment with inhibitors of oxidative phosphorylation. In this study we investigated the effect of a combination of 2-deoxy-D-glucose with lovastatin (a known inhibitor of mevalonate pathway and oxidative phosphorylation) on growth of KRAS-mutant human colorectal cancer cell lines HCT116 and LoVo. A combination of lovastatin (>3.75 µM) and 2-deoxy-D-glucose (>1.25 mM) synergistically reduced cell viability, arrested cells in the G2/M phase, and induced apoptosis. The combined treatment also reduced cellular oxygen consumption and extracellular acidification rate, resulting in decreased production of ATP and lower steady-state ATP levels. Energy depletion markedly activated AMPK, inhibited mTOR and RAS signaling pathways, eventually inducing autophagy, the cellular pro-survival process under metabolic stress, whereas inhibition of autophagy by chloroquine (6.25 µM) enhanced the cytotoxic effect of the combination of lovastatin and 2-deoxy-D-glucose. These in vitro experiment results were reproduced in a nude mouse xenograft model of HCT116 cells. Our findings suggest that concurrently targeting glycolysis, oxidative phosphorylation, and autophagy may be a promising regimen for the management of RAS-driven colorectal cancers.


Assuntos
Autofagia/fisiologia , Neoplasias Colorretais/genética , Desoxiglucose/administração & dosagem , Lovastatina/administração & dosagem , Mutação/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Animais , Antimetabólitos/administração & dosagem , Autofagia/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Cloroquina/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Feminino , Células HCT116 , Células HEK293 , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Mutação/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
16.
J Environ Sci (China) ; 104: 216-224, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33985724

RESUMO

The nondestructive characterization of the mixing state of individual fine particles using the traditional single particle analysis technique remains a challenge. In this study, fine particles were collected during haze events under different pollution levels from September 5 to 11 2017 in Beijing, China. A nondestructive surface-enhanced Raman scattering (SERS) technique was employed to investigate the morphology, chemical composition, and mixing state of the multiple components in the individual fine particles. Optical image and SERS spectral analysis results show that soot existing in the form of opaque material was predominant during clear periods (PM2.5 ≤ 75 µg/m3). During polluted periods (PM2.5 > 75 µg/m3), opaque particles mixed with transparent particles (nitrates and sulfates) were generally observed. Direct classical least squares analysis further identified the relative abundances of the three major components of the single particles: soot (69.18%), nitrates (28.71%), and sulfates (2.11%). A negative correlation was observed between the abundance of soot and the mass concentration of PM2.5. Furthermore, mapping analysis revealed that on hazy days, PM2.5 existed as a core-shell structure with soot surrounded by nitrates and sulfates. This mixing state analysis method for individual PM2.5 particles provides information regarding chemical composition and haze formation mechanisms, and has the potential to facilitate the formulation of haze prevention and control policies.


Assuntos
Poluentes Atmosféricos , Material Particulado , Aerossóis/análise , Poluentes Atmosféricos/análise , Pequim , China , Monitoramento Ambiental , Tamanho da Partícula , Material Particulado/análise , Estações do Ano , Análise Espectral Raman
17.
Anal Chem ; 92(24): 16229-16235, 2020 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-33216549

RESUMO

Antibiotic resistance genes (ARGs) have become emerging environmental contaminants, and the effective on-site detection of ARGs is urgently needed. Herein, we constructed a hairpin-structured magnetic sensor for the analysis of a widespread ARG, tetA, using surface-enhanced Raman scattering (SERS). The SERS sensor was assembled by immobilizing core-satellite structured Fe3O4@SiO2-Au with single-stranded DNA in a folded hairpin structure. The SERS sensor exhibited good sensitivity and specificity for the detection of laboratory-synthesized tetA ssDNA fragments. In addition, this SERS strategy is the first of its kind to be employed for monitoring environmental samples in the field, with a limit of detection reaching as low as 25 copies µL-1. Univariate and multivariate linear regression equations verify the practicability of the SERS sensor for quantitative tetA determination, showing the prospect for an amplification-free alternative platform for sensitive and reliable on-site detection of ARGs in the environment.


Assuntos
Antiporters/genética , Proteínas de Bactérias/genética , Óxido Ferroso-Férrico/química , Sequências Repetidas Invertidas , Fenômenos Magnéticos , Análise Espectral Raman , Resistência a Tetraciclina/genética , Tetraciclina/farmacologia , DNA de Cadeia Simples/química , Ouro/química , Limite de Detecção , Dióxido de Silício/química
18.
J Exp Bot ; 71(12): 3499-3511, 2020 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-32149350

RESUMO

In planta, a vital regulatory complex, MYB-basic helix-loop-helix (bHLH)-WD40 (MBW), is involved in trichome development and synthesis of anthocyanin and proanthocyanin in Arabidopsis. Usually, WD40 proteins provide a scaffold for protein-protein interaction between MYB and bHLH proteins. Members of subgroup 9 of the R2R3 MYB transcription factors, which includes MYBMIXTA-Like (MML) genes important for plant cell differentiation, are unable to interact with bHLH. In this study, we report that a cotton (Gossypium hirsutum) seed trichome or lint fiber-related GhMML factor, GhMML4_D12, interacts with a diverged WD40 protein (GhWDR) in a process similar to but different from that of the MBW ternary complex involved in Arabidopsis trichome development. Amino acids 250-267 of GhMML4_D12 and the first and third WD40 repeat domains of GhWDR determine their interaction. GhWDR could rescue Arabidopsis ttg1 to its wild type, confirming its orthologous function in trichome development. Our findings shed more light towards understanding the key role of the MML and WD40 families in plants and in the improvement of cotton fiber production.


Assuntos
Proteínas de Arabidopsis , Fatores de Transcrição , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Regulação da Expressão Gênica de Plantas , Gossypium/genética , Gossypium/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Repetições WD40
19.
FASEB J ; 33(2): 1911-1926, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30216112

RESUMO

Skeletal muscle is an important and complex organ with a variety of functions in humans and animals. Skeletal myogenesis is a multistep and complex process, and increasing evidence suggests that microRNAs (miRNAs) and long noncoding RNAs (lncRNAs) play critical roles in skeletal myogenesis. In this study the expression of miR-351-5p is dynamically regulated during skeletal myogenesis in vitro and in vivo. Cell-counting kit-8, qRT-PCR, and EdU immunofluorescence analysis showed that miR-351-5p overexpression promoted the proliferation and inhibited the differentiation of C2C12 myoblast, whereas inhibition of miR-351-5p had the opposite effect. In addition, miR-351-5p mediated the regulation of muscle fiber type transition in vivo. In vitro, loss of miR-351-5p in muscle tissues promoted muscle hypertrophy and increased slow-twitch fibers in the gastrocnemius muscles of mice. Luciferase reporter assay and functional analyses demonstrated that lactamase ß ( LACTB) is a direct target of miR-351-5p involved in the regulation of skeletal myogenesis. Expression levels of a myogenesis-associated lncRNA ( lnc-mg) correlated negatively with miR-351-5p and positively with LACTB during C2C12 myoblast proliferation and differentiation. Further analyses showed that lnc-mg acted as a molecular sponge for miR-351-5p, demonstrating its involvement in the negative regulation of LACTB by miR-351-5p during skeletal myogenesis. These findings indicate that miRNA-351-5p functions in skeletal myogenesis by targeting LACTB and is regulated by lnc-mg, supporting the role of the competing endogenous RNA network in skeletal myogenesis.-Du, J., Zhang, P., Zhao, X., He, J., Xu, Y., Zou, Q., Luo, J., Shen, L., Gu, H., Tang, Q., Li, M., Jiang, Y., Tang, G., Bai, L., Li, X., Wang, J., Zhang, S., Zhu, L. MicroRNA-351-5p mediates skeletal myogenesis by directly targeting lactamase ß and is regulated by lnc-mg.


Assuntos
Proteínas de Membrana/metabolismo , MicroRNAs/metabolismo , Desenvolvimento Muscular , Fibras Musculares de Contração Lenta/metabolismo , Proteínas Musculares/metabolismo , Mioblastos Esqueléticos/metabolismo , RNA Longo não Codificante/metabolismo , Proteínas Ribossômicas/metabolismo , Animais , Diferenciação Celular/genética , Linhagem Celular , Proliferação de Células/genética , Proteínas de Membrana/genética , Camundongos , MicroRNAs/genética , Fibras Musculares de Contração Lenta/citologia , Proteínas Musculares/genética , Mioblastos Esqueléticos/citologia , RNA Longo não Codificante/genética , Proteínas Ribossômicas/genética
20.
Xenobiotica ; 50(11): 1352-1358, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29171786

RESUMO

Genistein is a widely studied phytoestrogen. The effects of genistein on myoblasts were reported long ago, but the conclusions are controversial. In this study, we evaluated the effects of different concentrations of genistein on C2C12 myoblasts. Genistein treatment promoted myoblast proliferation in a dose-dependent manner in the concentration range of 0-2 µM/L, reaching its maximum effect at 2 µM/L. Proliferation then declined, and a concentration higher than 20 µM/L showed significant inhibition. In addition, genistein treatment promoted myoblast differentiation at a dose of 10 µM/L. However, at treatment concentrations higher than 10 µM/L, the effect on myoblast differentiation was rapidly inhibited as the concentration increased. Genistein treatment also down-regulated the expression of miR-222, resulting in increased expression of its target genes, MyoG, MyoD, and ERα and thereby promoting myoblast differentiation. Our results suggest that genistein has a dose-dependent and bidirectional regulation effect on myoblast proliferation and differentiation. We also found that genistein is a miRNA inducer, and it specifically affects the expression of miR-222 to regulate myoblast differentiation.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Genisteína , Mioblastos/efeitos dos fármacos , Fitoestrógenos , Humanos , Mioblastos/metabolismo , Mioblastos/fisiologia
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