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1.
Int J Mol Sci ; 21(3)2020 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-32050491

RESUMO

Testosterone (T) is essential for muscle fiber formation and growth. However, the specific mechanism by which T regulates skeletal muscle development in chicken embryos remains unclear. In this study, the role of T in myoblast proliferation both in vivo and in vitro was investigated. Results showed that the T administration significantly increased the ratio of breast muscle and leg muscle. T induced a significant increase in the cross-sectional area (CSA) and density of myofiber and the ratio of PAX7-positive cells in the skeletal muscle. Exogenous T also induced the upregulation of myogenic regulatory factors (MRFs) and cyclin-dependent kinases (CDK2)/Cyclin D1 (CCND1) and protein levels of androgen receptor (AR), p-Akt and PAX7. Furthermore, T treatment significantly promoted myoblasts cultured in vitro entering a new cell cycle and increased PAX7-positive cells. The mRNA and protein expression of AR and PAX7 were upregulated when treated with T compared to that of the control. The addition of T induced proliferation accompanied by increasing AR level as well as PI3K (Phosphoinositide 3-kinase)/Akt activation. However, T-induced proliferation was attenuated by AR, PI3K, and Akt-specific inhibitors. These data indicated that the pro-proliferative effect of T was regulated though AR in response to the activation of PI3K/Akt signalling pathway.

2.
Sci Total Environ ; 702: 134803, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31731125

RESUMO

Photosynthetic picoeukaryotes (PPEs) are key players in aquatic systems, while their diversity and community composition dynamics remain poorly understood. The monthly composition of PPEs in Lake Chaohu was investigated using a combination of flow cytometry sorting and high throughput sequencing. Results indicated that temperature is the most important factor shaping PPEs community structure. The PPEs community can be categorized into three groups that are dominant at different temperature ranges: high temperature (>21.8 °C), intermediate temperature (between 9.8 °C and 21.8 °C) and low temperature (<9.8 °C). At the supergroup level, Cryptophyta were dominant at the intermediate temperature level, and Bacillariophyta were prevalent at low temperatures. In comparison, Chlorophyta PPEs were sensitive to temperature at the order level. Molecular network analysis using 18S rDNA sequencing results from sorted samples revealed that the Operational Taxonomic Units (OTUs) of PPE from the same taxonomic groups were predominantly positive, implying that they were occupying similar niches. The cooccurrence patterns between PPEs and fungi were mostly negative. In particular, OTU101, which was associated with Chytridiomycota, was negatively related to many OTUs belonging to Chlorophyta and Diatom, indicating that their potential parasitic associations may be not species-specific.


Assuntos
Lagos/microbiologia , Temperatura Ambiente , Microbiologia da Água , Clorófitas , Monitoramento Ambiental , Haptófitas , Fotossíntese
3.
Yi Chuan ; 41(9): 836-844, 2019 Sep 20.
Artigo em Chinês | MEDLINE | ID: mdl-31549682

RESUMO

Wheat is one of the main food crops and widely grown in the world. It feeds more than 35% of the world's population. Obtaining high-quality genome sequences of wheat is important for its basic and breeding researches. However, the large and complex genome of wheat once led to its genome sequencing as an "impossible task". Recently, with the development of high-throughput sequencing and assembly technology, many wheat genome sequences have been released, and their sequencing and assembly quality is being improved continuously. In the last two years, five wheat reference genomes with different ploidy levels have been published, including two diploid ancestors Triticum urartu (AA) and Aegilops tauschii (DD), wild and cultivated tetraploid wheat T. turgidum ssp. dicoccoides (BBAA) and hexaploid wheat T. aestivum (BBAADD). Among them, the sequencing and analysis of the T. urartu genome, a donor of polyploid wheat A subgenome, was led by the Institute of Genetics and Developmental Biology of the Chinese Academy of Sciences. In this review, we summarize the research progress on structure and evolution analyses of the T. urartu genome to provide some valuable information for promoting the basic and applied researches of wheat.


Assuntos
Genoma de Planta , Triticum/genética , Aegilops/genética , Mapeamento Cromossômico , Poliploidia , Triticum/classificação
4.
Front Microbiol ; 10: 2016, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31551958

RESUMO

Spatial and seasonal dynamics of picophytoplankton were investigated by flow cytometry over a year in Lake Fuxian, a deep and oligotrophic mountain lake in southwest China. The contribution of picophytoplankton to the total Chl-a biomass and primary production were 50.1 and 66.1%, respectively. Picophytoplankton were mainly composed of phycoerythrin-rich picocyanobacteria (PE-cells) and photosynthetic picoeukaryotes (PPEs). PPEs were dominant in spring, reaching a maximum cell density of 3.0 × 104 cell mL-1, while PE-cells were prevalent in other seasons. PE-cell abundance was relatively similar throughout the year, except for a decrease in summer during the stratification period, when nutrient concentration was low. High-throughput sequencing results from the sorted samples revealed that Synechococcus was the major PE-cell type, while Chrysophyceae, Dinophyceae, Chlorophyceae, Eustigmatophyceae, and Prymnesiophyceae were equally important PPEs. In spring, PPEs were mainly composed of Chlorophyceae and Trebouxiophyceae, while in summer, their dominance was replaced by that of Chrysophyceae and Prymnesiophyceae. Eustigmatophyceae and Chlorophyceae became the major PPEs in autumn, and Dinophyceae became the most abundant in winter. Single cells of Microcystis were usually detected in summer in the south, suggesting the deterioration of the water quality in Lake Fuxian.

5.
Sci Total Environ ; 694: 133721, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31400686

RESUMO

The use of short-term, fast-acting curative treatments to rapidly suppress the proliferation of upcoming cyanobacterial blooms without negative side effects on overall water quality is important for environmental regulatory agencies. A 15-day in situ mesocosm experiment was conducted to evaluate the effects of algal harvest at different intensities and the effect of hydrogen peroxide on the mitigation of cyanobacterial blooms, subsequent algal growth and phytoplankton community structure. The results indicate that filtration through a 30-µm-pore-size net could remove most of the Microcystis colonies, leading to a decline in algal biomass. However, algal harvest at 30% and 60% intensities tended to promote cyanobacterial growth under nutrient-replete conditions, and the mitigation effect only lasted a few days, since cyanobacteria biomass exhibited no significant difference between the control and those two treatments on Day 6. When the algal harvest intensity was 90%, the cyanobacterial biomass remained at a relatively low level for 15 days. The average Microcystis colony size rapidly returned to the initial level after an initial decline across all the algal harvest intensities, indicating that algal harvest should be repeatedly performed within a short time period to mitigate Microcystis blooms. Furthermore, removing Microcystis colonies by filtration led to increased diversity in the phytoplankton community, as the proportion of non-Microcystis cyanobacteria increased with harvest intensity. This result might pose a challenge for cyanobacterial bloom control over the long term if filamentous cyanobacteria become dominant. The 10.0 mg L-1 H2O2 treatment selectively suppressed cyanobacteria throughout the experimental period, leading to succession from a cyanobacteria-dominated to a Chlorophyta-dominated community after Day 9. Overall, using hydrogen peroxide is more effective than algal harvesting as a one-time quick curative measure.


Assuntos
Cianobactérias/crescimento & desenvolvimento , Recuperação e Remediação Ambiental/métodos , Proliferação Nociva de Algas , Peróxido de Hidrogênio , Monitoramento Ambiental , Microalgas , Microcistinas , Microcystis , Fitoplâncton/crescimento & desenvolvimento
6.
Artigo em Inglês | MEDLINE | ID: mdl-31238577

RESUMO

The landscape grain effect reflects the spatial heterogeneity of a landscape and it is used as a research core of landscape ecology. The landscape grain effect can be used to not only explore spatiotemporal variation characteristics of a landscape pattern, but also to disclose variation laws of ecological structures and functions of landscapes. In this study, the sensitivity of landscape pattern indexes to grain sizes 50-1000 m was studied based on landscape data in Yancheng Coastal Wetland acquired in 1991, 2000, 2008, and 2017. Response of the grain effect to landscape changes was analyzed and an optimal grain size for analysis in the study area was determined. Results indicated that: (1) among 27 indexes (12 in a class level and 15 in a landscape level), eight indexes were highly sensitive to grains, ten indexes presented moderate sensitivity, eight indexes presented low sensitivity, and one was unresponsive. It was shown that the area-margin index and the shape index were more sensitive to the different grain sizes. The aggregation index had some differences in the grain size change, and the diversity index had a low response degree to the grain size. (2) Landscape indexes showed six different responses to different grains, including slow reduced response, fast reduced and then slow reduced response, monotonically increased response, fluctuating reduced response, up-down responses, and stable response, which indicated that the landscape index was closely related to the spatial grain. (3) From 1991 to 2017, variation curves of the landscape grain size of different landscape types could be divided into four types: fluctuation rising type, fluctuation type, monotonous decreasing type, and monotonous rising type. Different grain size curves had different interpretations of landscape changes, but in general, Yancheng Coastal Wetland's landscape tended to be fragmented and complicated, internal connectivity was weakened, and dominant landscape area was reduced. Natural wetlands were more sensitive to grain size effects than artificial wetlands. (4) The landscape index at the 50 m grain size had a strong response to different grain size changes, and the loss of landscape information was the smallest. Therefore, it was determined that the optimal landscape grain size in the study area was 50 m.


Assuntos
Fenômenos Ecológicos e Ambientais , Áreas Alagadas , China
7.
Sci Total Environ ; 686: 893-902, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31200309

RESUMO

Hexabromocyclododecane (HBCD) is a widely applied brominated flame retardant (BFR) and is regarded as a persistent organic pollutant. It has been found in human tissues and has the potential to cause neurological disorders. However, our understanding of HBCD neurotoxicity at the diastereoisomer level remains lacking. Here, we investigated the neurotoxicity of three HBCD diastereoisomers, i.e., α-, ß-, and γ-HBCD, in SH-SY5Y human neuroblastoma cells. Results showed that the HBCD diastereoisomers decreased cell viability, increased lactate dehydrogenase (LDH) release, and impaired cytoskeleton development. Typical morphological features and apoptosis rates showed that the HBCD diastereoisomers induced SH-SY5Y cell apoptosis. The expression levels of several cell apoptosis-related genes and proteins, including Bax, caspase-3, caspase-9, cytochrome c, Bcl-2, and X-linked inhibitor of apoptosis (XIAP), as well as the cell cycle arrest, DNA damage, adenosine triphosphate (ATP) consumption, reactive oxygen species (ROS) levels, and intracellular calcium ion (Ca2+) levels, were examined. Results showed that the HBCD diastereoisomer neurotoxicity was ranked ß-HBCD > γ-HBCD > α-HBCD. The cell apoptosis and caspase expression levels of the three HBCD diastereoisomers followed the same order, suggesting that caspase-dependent apoptosis may be one mechanism responsible for the structure-selective HBCD diastereoisomer neurotoxicity. The levels of intracellular Ca2+ and ROS increased significantly. The ROS levels were ordered ß-HBCD > γ-HBCD > α-HBCD, whereas those of intracellular Ca2+ were γ-HBCD > ß-HBCD > α-HBCD. Thus, ROS may be a key factor regulating the neurotoxicity of HBCD diastereoisomers. To the best of our knowledge, this is the first study to report on the diastereoisomer-specific toxicity of HBCD in human neural cells and on the possible mechanisms responsible for the selective neurotoxicity of HBCD diastereoisomers.


Assuntos
Poluentes Ambientais/toxicidade , Hidrocarbonetos Bromados/toxicidade , Sistema Nervoso/efeitos dos fármacos , Apoptose , Linhagem Celular Tumoral , Sobrevivência Celular , Dano ao DNA , Retardadores de Chama , Humanos , Neuroblastoma , Proteínas Proto-Oncogênicas c-bcl-2 , Espécies Reativas de Oxigênio , Testes de Toxicidade
8.
Anim Cells Syst (Seoul) ; 23(3): 155-163, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31231578

RESUMO

N-(2-pyridylmethyl)-2-hydroxiymethyl-1-pyrrolidinyl-4-(3-chloro-4-methoxy-benzylamino)-5-pyrimidine-carboxamide (NHPPC) is a new potential of type 5 phosphodiesterase (PDE5) inhibitors, synthesized from the avanafil analogue for the treatment of erectile dysfunction. The targets of this article were to assess plasma protein binding, liver microsomal metabolic stability, inhibition and induction on cytochrome P450 isozymes and the pharmacokinetics of NHPPC. Equilibrium dialysis technique was applied to determine Plasma protein binding (PPB) and NHPPC was evaluated in male Sprague-Dawley rats and Beagle dogs in vivo pharmacokinetic. The NHPPC was highly bound to plasma proteins in rats, dogs and human tested and the mean values for PPB rate were 96.2%, 99.6% and 99.4%, respectively. After in vitro liver microsomes incubated for 60 min, the percent remaining of NHPPC was 42.8%, 0.8% and 42.0% in rats, dogs and human, respectively. In vitro intrinsic clearance was found to be 0.0233, 0.1204 and 0.0214 mL/min/mg protein in rat, dog and human liver microsomes of NHPPC, respectively. NHPPC showed no significant inhibitory effects on major CYP450 enzymes, and had no significant induction potential on CYP1A2 and CYP3A4. Following oral administration in rats and dogs, t max was 6 and 0.5 h, respectively. The clearance for NHPPC was 1.19 and 1.46 L/h/kg in rats and dogs, respectively. And absolute bioavailability in rat and dog were approximately 34.5% and 53.1%, respectively. These results showed that NHPPC has a good development prospect.

10.
PLoS One ; 14(4): e0211182, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30958828

RESUMO

In order to screen the candidate genes of Fenneropenaeus chinensis related to low-temperature tolerance, this research takes juvenile prawns of F. chinensis (P40) in low temperature stress group (4°C) and normal temperature group (18°C) as experimental materials. The results showed that a total of 127,939 Unigenes with average length of 1,190 bp were obtained by assembly, of which 46% were annotated in the Nr database. A total of 1,698 differentially expressed genes were screened by differential gene expression analysis, of which 920 genes showed up-regulated expression and 778 genes showed down-regulated expression. Both GO and KEGG enrichment analysis revealed that differentially expressed genes were enriched in spliceosomes, ribosomes, bile secretion, ABC transport pathways, and cellular nitrogen compound synthesis. A further in-depth analysis obtained 8 genes that may be associated with low-temperature traits of F. chinensis. Five of them displayed up-regulated expression, including ATP-binding cassette protein C, acid ceramidase, glutathione transferase, C-type lectin and heat shock protein HSP70. The remaining three genes, γ-butyl betaine hydroxylase, ß-hexosaminidase A and long chain fatty acid-CoA ligase displayed down-regulated expression. Eight differentially expressed genes were randomly selected and the real time RT-PCR verification showed that their expression levels were consistent with the sequencing results, demonstrating the accuracy of the sequencing results. The results of this study provide basic data for revealing the molecular mechanisms of F. chinensis in response to low temperature stress and the molecular assisted breeding of F. chinensis in low temperature.


Assuntos
Aclimatação/genética , Aquicultura/métodos , Temperatura Baixa/efeitos adversos , Penaeidae/fisiologia , Animais , China , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Redes e Vias Metabólicas/genética , Alimentos Marinhos , Seleção Artificial , Transcriptoma/genética , Sequenciamento Completo do Exoma
11.
Biochem Biophys Res Commun ; 513(3): 560-566, 2019 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-30981507

RESUMO

Both type 1 and type 2 diabetes are associated with loss of functional beta cell mass, and strategies to restore beta cells are urgently needed. We reported previously that overexpression of the nuclear receptor TLX induces beta cell proliferation, but the underlying molecular mechanism has not been defined. Here, we identified direct targets of TLX in beta cells at the genome-wide level by ChIP-Seq. These targets include a cadre of regulators that are known to be critical for proliferation. Among these ChIP targets, E2F6 was tightly associated with the cell cycle modules, and thus, we further analyzed E2F6 expression and function in beta cells. We showed that E2F6 is strongly downregulated by TLX, and its expression inhibits beta cell proliferation. Moreover, coexpression of E2F6 with TLX partially abrogated the proliferative effects of TLX. These results strongly suggest that TLX acts through E2F6 to regulate beta cell proliferation. Together, the results of this study reveal a direct interaction between TLX and E2F6 and suggest new targets for the expansion of functional beta cell mass.

12.
Adv Mater ; 31(45): e1804950, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30815920

RESUMO

Cells sense and respond to a wide range of external signals, including chemical signals, topography, and interface mechanics, via interactions with the extracellular matrix (ECM), triggering the regulation of behavior and function. The ECM can be considered a hierarchical multiphase porous matrix with various components. Highly porous hydrogel-based biomaterials can mimic the critical ECM properties, to provide mechanical support for tissues and to regulate cellular behaviors, such as adhesion, proliferation, and differentiation. Herein, based on micro/nanoscale-topography-coupled mechanical action, recent advances in the fabrication and application of hydrogel composites with tunable mechanical properties and topography in biomedicine are summarized. In particular, recent findings showing that hydrogels with specifically designed structures not only influence a range of cellular processes and fit the needs of engineered tissues but also have pharmacological effects are emphasized.

13.
Chemosphere ; 221: 526-532, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30660909

RESUMO

Potentially toxic algae-induced black blooms can trigger crises in urban water supplies and have fatal effects on aquatic ecosystems. Urgent disposal methods to mitigate the taste and odor are imperative for ensuring the safety of the drinking water supply. In this study, we tested three oxidants and two flocculants to improve water quality after the occurrence of a black bloom. The results indicated that a two-step integrated treatment process is efficient as an urgent disposal measure. The first step is removal of volatile organic sulfide compounds (VOSCs) through the addition of H2O2. A total of 50 mg/L of H2O2 can largely decrease the concentrations of dimethyl trisulfide and related alkyl sulfide compounds in the water column. The second step is the flocculation and sedimentation of black-bloom-induced black matter via a chitosan-modified clay. The addition of 1 g/L of an attapulgite clay plus 10 mg/L of chitosan can effectively deposit suspended matter on the bottom of the water column and have a positive effect on the removal of nutrients.


Assuntos
Eutrofização , Odorantes , Purificação da Água/métodos , Quitosana/química , Argila/química , Água Potável/química , Floculação , Peróxido de Hidrogênio/farmacologia , Sulfetos/isolamento & purificação , Compostos Orgânicos Voláteis/isolamento & purificação
14.
Cancer Chemother Pharmacol ; 83(1): 179-189, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30406839

RESUMO

OBJECTIVE: To investigate the potential inhibitory effects of structurally novel steroidal dimer by001 in esophageal cancer in vitro. METHODS: The cytotoxicity of by001 on esophageal, gastric, neuroblastoma and prostate cancer cells was examined MTT assay and colony formation assay. By001 induced apoptosis and production of intracellular reactive oxygen species on esophageal cancer cells Ec109, TE-1 and human normal gastric epithelial cells GES-1 was detected by flow cytometry. The effect of by001 on mitochondrial membrane potential was detected by fluorescence microscope through JC-1 staining. The level of intracellular reactive oxygen species was measured by fluorescence microscope and flow cytometry via DCFH-DA staining. The effect of by001 on members of Bcl-2 family, Fas, LC3, PARP and caspases was determined by Western blot. The effect of by001 on migration was measured by transwell assay. RESULTS: By001 effectively inhibited proliferation of esophageal, gastric, neuroblastoma and prostate cancer cells in a time- and concentration-dependent manner in vitro. By001 reduced the number and the size of colonies at low micromolar concentrations, elevated cellular ROS levels and caused mitochondrial dysfunction in esophageal cancer cells. Molecular mechanistic studies showed that by001 triggered apoptosis through regulating members of Bcl-2 family and Fas. CONCLUSIONS: These findings suggested that by001 may inhibited proliferation of esophageal cancer cells through mitochondria and death receptor-mediated apoptotic pathways, autophagy induction, as well as suppressed migration of esophageal cancer cells.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Neoplasias Esofágicas/tratamento farmacológico , Compostos Policíclicos/química , Compostos Policíclicos/farmacologia , Esteroides/química , Apoptose , Neoplasias Esofágicas/patologia , Humanos , Potencial da Membrana Mitocondrial , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Estrutura Molecular , Espécies Reativas de Oxigênio/metabolismo , Relação Estrutura-Atividade , Células Tumorais Cultivadas
15.
FEMS Microbiol Ecol ; 95(1)2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30346526

RESUMO

Lake Poyang, which is connected to the Yangtze River, is the largest freshwater lake in China and experiences large and frequent changes in water levels. The seasonal diversity and composition of photosynthetic picoeukaryotes (PPEs) in Lake Poyang were investigated from flow-cytometry-sorted samples using MiSeq high-throughput sequencing. Flow cytometric counting indicated that PPEs accounted for 97% of the total picophytoplankton abundance in spring, reaching a maximum value of 6.30 × 104 cells mL-1. PPEs in Lake Poyang showed lower diversity than those in other investigated lakes in the lower reaches of the Yangtze River and were dominated by one OTU (66.29%) affiliated with Mychonastes (Chlorophyceae). Other minor classes of PPEs were found to be sporadically abundant in specific seasons, i.e. Chrysophyceae prevailed in spring and summer, while Eustigmatophyceae was mainly present in winter. This study reports coccal green algae of Mychonastes in Lake Poyang; additionally, these algae are reportedly representative of the prominent plankton in this river-connected lake ecosystem but are often overlooked due to their lack of morphological features. Finally, the sequencing results from the sorted samples of Lake Poyang revealed that the proportion of PPEs was quite low, with an average of 36% of total reads. Many OTUs belonging to heterotrophic picoeukaryotes were also identified in the sorted samples, most of which were affiliated with terrestrial fungi, including Basidiomycota and Ascomycota. The spores of these fungi can disperse in the aquatic environment during the flood seasons, yet their effect on PPEs is still unclear.


Assuntos
Clorófitas/metabolismo , Eucariotos/metabolismo , Fotossíntese , Biodiversidade , China , Clorófitas/classificação , Clorófitas/genética , Ecossistema , Eucariotos/classificação , Eucariotos/genética , Eucariotos/isolamento & purificação , Lagos/parasitologia , Rios/parasitologia , Estações do Ano
16.
Plant Mol Biol ; 99(1-2): 31-44, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30519824

RESUMO

KEY MESSAGE: In this manuscript, we explored the key molecular networks for oil biosynthesis with the transcriptome and metabolome of B. napus embryo at different developmental stages. Brassica napus (B. napus) is an important oil crop worldwide, yet the molecular pathways involved in oil biosynthesis in seeds are not fully understood. In this study, we performed a combined investigation of the gene expression profiles and metabolite content in B. napus seeds at 21, 28 and 35 days after flowering (DAF), when seed oil biosynthesis takes place. The total triacylglycerol (TAG) content in seed embryos increased over the course of seed maturation, and was accompanied by changes in the fatty acid profile, an increase in lipid droplets, and a reduction in starch grains. Metabolome analysis showed that the total amino acid, free fatty acid and organic acid contents in seed embryos decreased during seed maturation. In total, the abundance of 76 metabolites was significantly different between 21 and 28 DAF, and 68 metabolites changed in abundance between 28 and 35 DAF. Transcriptome analysis showed that the set of genes differentially expressed between stages was significantly enriched in those related to lipid metabolism, transport, protein and RNA metabolism, development and signaling, covering most steps of plant lipid biosynthesis and metabolism. Importantly, the metabolite and gene expression profiles were closely correlated during seed development, especially those associated with TAG and fatty acid biosynthesis. Further, the expression of major carbohydrate metabolism-regulating genes was closely correlated with carbohydrate content during seed maturation. Our results provide novel insights into the regulation of oil biosynthesis in B. napus seeds and highlights the coordination of gene expression and metabolism in this process.


Assuntos
Brassica napus/genética , Regulação da Expressão Gênica de Plantas , Metabolismo dos Lipídeos/genética , Metaboloma , Transcriptoma , Brassica napus/embriologia , Brassica napus/metabolismo , Ácidos Graxos/análise , Ácidos Graxos/metabolismo , Perfilação da Expressão Gênica , Óleos Vegetais/metabolismo , Sementes/embriologia , Sementes/genética , Sementes/metabolismo
17.
Small ; 14(52): e1803715, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30430733

RESUMO

Gold nanorods (AuNRs), with their unique physicochemical properties, are recognized as promising materials for biomedical applications. Chemical modification of their surfaces is attracting increasing attention with regard to cytotoxicity and cellular uptake. Herein, the toxicological effects of three types of polymer-coated AuNRs, which are cetyltrimethylammonium bromide-coated AuNRs, polystyrene sulphonate-coated AuNRs, and poly(diallyldimethyl ammonium chloride-coated AuNRs (PDDAC-AuNRs), on vascular smooth muscle cells (VSMCs) are investigated. The results show significantly different effects on VSMCs with different surface coatings. PDDAC-AuNRs, which were nontoxic in cancer cells in previous reports, display extreme toxicity to VSMCs. Initial contact between AuNRs and cell membranes is the important step in AuNRs cellular uptake. Force spectroscopy based on atomic force microscopy is exploited to study interactions between AuNRs and VSMCs membrane in the absence or presence of a corona on the AuNRs surface. The results show that the binding force and binding probability between AuNRs and membranes are closely related to cytotoxicity and cellular responses. These findings highlight the importance of assessing nanoparticle cytotoxicity in somatic cells for medical applications.


Assuntos
Ouro/química , Nanopartículas Metálicas/química , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/citologia , Nanotubos/química , Compostos Alílicos/química , Materiais Biocompatíveis/química , Humanos , Compostos de Amônio Quaternário/química
18.
R Soc Open Sci ; 5(8): 180159, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30225009

RESUMO

Gold nanoparticles and carbon nanotubes have attracted substantial attention in recent years for their potential applications in photothermal therapy (PTT) as an emerging breakthrough in cancer treatment. Herein, a hybrid nanomaterial of gold nanostars/multiwalled carbon nanotubes (MWCNTs) was synthesized by two-step reduction via the control of several synthetic conditions such as the reducing agent, pH value, concentration and ratio of reagents. The material shows good biocompatibility and high photothermal conversion efficiency, demonstrating its applicability in PTT. The lack of surfactant in the synthesis process made the hybrid nanomaterial cell-friendly, with no effects on viability in vitro. The MWCNT/gold nanostars hybrid nanomaterial presented 12.4% higher photothermal efficiency than gold nanostars alone and showed a 2.4-fold increase over gold nanospheres based on a heating test under 808 nm laser irradiation. Moreover, the MWCNTs/gold nanostars at low concentration (0.32 nM) exhibited remarkably improved photothermal cancer cell-killing efficacy, which may be attributed to the surface plasmon resonance absorption of the gold nanostars and the combined effects of enhanced coupling between the MWCNTs and gold nanostars. Collectively, these results demonstrate that the MWCNTs/gold nanostars developed herein show prominent photothermal value, and thus may serve as a novel photothermal agent for cancer therapy.

19.
Sci Total Environ ; 645: 876-886, 2018 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-30032083

RESUMO

Understanding the relative effect sizes of climate-related environmental variables and nutrients on the high annual variation in the phytoplankton biomass in eutrophic lakes is important for lake management efforts. In this study, we used a data set of phytoplankton dynamics in eutrophic Lake Taihu that cover more than two decades (1993-2015) to show the variation in and the drivers of phytoplankton biomass under complex, fluctuating environmental conditions. Our results showed that the phytoplankton biomass increased slowly over the studied period despite the recent decrease in nutrient levels. The distribution of the phytoplankton biomass expanded spatially towards the central lake region, and seasonally towards the autumn and winter. Nutrients were still the primary predictors of the long-term phytoplankton biomass trend. The effect size of climate-related variables was also high and close to the effect size of nutrients. Among the climate-related variables, wind speed and underwater available light were more important predictors than temperature. The biomass of the phytoplankton taxonomic groups showed different responses to the environmental variables based on their niches. However, the compensatory dynamics affecting biomass were weak at phylum level, and synchronous dynamics drove the variation in total biomass. Our findings highlight the effect of climate-related variables on the phytoplankton biomass in Lake Taihu, which has experienced high nutrient loadings and concentrations for more than two decades. Therefore, changes in climate-related variables, such as wind speed and underwater available light, should be considered when evaluating the amount that nutrients should be reduced in Lake Taihu for future lake management.


Assuntos
Biomassa , Monitoramento Ambiental , Eutrofização , Lagos/química , Fitoplâncton/crescimento & desenvolvimento , China , Vento
20.
Med Sci Monit ; 24: 4583-4591, 2018 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-29968701

RESUMO

BACKGROUND The pathogenesis of chronic intermittent hypoxia (CIH)-induced abnormal hepatic lipid metabolism in rats remains unclear. Here, we investigated the therapeutic effect of N-acetylcysteine (NAC) on abnormal hepatic lipid metabolism. MATERIAL AND METHODS Rats were subjected to hypoxia and NAC treatment, and evaluated in terms of hepatic lipid metabolism, hepatocyte ultrastructure, oxidative stress in hepatocytes, expression of nuclear factor-kappa B (NF-κB) and inflammatory cytokines (IL-1ß, IL-6, and TNFα), serum lipoprotein lipase (LPL) levels, and blood lipids (triglycerides and cholesterol). RESULTS Compared to the normoxic control group, animals in the hypoxic model group showed significant body weight gain; abnormal hepatic lipid metabolism; lipid vacuolization; accumulation of lipid droplets; abundant autophagosomes and lysosomes; significant increases in oxidative stress, inflammation level, and blood lipid levels; and significantly reduced LPL levels. Compared to control animals, rats in the treatment group exhibited normal body weight gain, improved lipid metabolism, fewer lipid droplets, alleviated ultrastructural injuries, decreased oxidative stress and inflammation level, as well as elevated LPL and reduced blood lipid levels. CONCLUSIONS The harmful effects of CIH on rat liver are possibly associated with the reactive oxygen species (ROS)/NF-κB signaling pathway. NAC is capable of attenuating lipid metabolism alterations and abnormal body weight gain in the CIH rat model, via a possible mechanism related to inhibition of ROS/NF-κB signaling.


Assuntos
Acetilcisteína/farmacologia , Hipóxia/tratamento farmacológico , Fígado/patologia , Acetilcisteína/metabolismo , Animais , Peso Corporal , Citocinas/metabolismo , Hipóxia/metabolismo , Hipóxia/fisiopatologia , Inflamação/patologia , Metabolismo dos Lipídeos/fisiologia , Fígado/metabolismo , Masculino , Estresse Oxidativo/fisiologia , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
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