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1.
Food Chem Toxicol ; : 110906, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31669603

RESUMO

Zinc oxide nanoparticles (ZnONPs) have been widely used in food storage containers and food additives in daily life. However, the impact of oral intake of ZnONPs on nervous system is extremely limited, especially on children and adolescents. In this study, four weeks old mice were treated with either vehicle or ZnONPs suspension solution at 26 mg/kg by intragastric administration for 30 days. Our results demonstrated that oral ZnONPs exposure could induce pathological changes in gut and abnormal excitement of enteric neurons. Interestingly, we found that ZnONPs caused enhancement of 5-hydroxytryptamine (5-HT) in gut by activation of its biosynthesis, transport and receptors, and subsequently resulting in increased level of 5-HT in brain via gut-brain communication by blood. Our data also showed that there were no apparent changes on the expressions of interleukin (Il)-6, Il-1ß, C-C motif chemokine ligand 2 (Ccl2), tumor necrosis factor (Tnf) in gut and zinc chelator Mt2 in gut and cortex. Meanwhile, no significant changes were observed on the expressions of tryptophan hydroxylase type 1, 5-HT receptor 3A (Htr3a) and Htr4 in hippocampus and cortex. Our study indicate that oral ZnONPs exposure causes hyperfunction of 5-HT in gut in young mice which may further spread to brain via gut-brain communication.

2.
Fitoterapia ; 139: 104366, 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31629868

RESUMO

Phytochemical investigation of the ethyl acetate extract of Lycopodiastrum casuarinoides (Spring) Holub (Lycopodiaceae) led to the isolation of nine compounds, including two new serratene triterpenoids, serrat-14-en-3α,21α-diol (1), 26-nor-8-oxo-21-one-α-onocerin (6), one new abietane diterpenoid, lycocasuarinone A (7), one new sesquiterpene acid, 7, 9-diene-1,4-epoxy-2-hydroxy-10-carboxylic acid (8) and one new chromone derivative, 5,7-dihydroxy-2-methyl esterchromone (9), together with four known serratene triterpenoids (2-5). Abietane diterpenoid (7) and sesquiterpene acid (8) from Lycopodiastrum casuarinoides are reported for the first time. Their structures and stereochemistry were unambiguously elucidated by spectroscopic analysis and comparison with known ones. All the compounds were tested for acetylcholinesterase (AChE) and butyrocholinesterase (BuChE) inhibitory activities. Bioactivity assays revealed that compound 6 exhibited the most potent AChE inhibitory effect.

3.
PLoS Genet ; 15(10): e1008443, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31661489

RESUMO

Arthropod-specific juvenile hormones control numerous essential functions in development and reproduction. In the dengue-fever mosquito Aedes aegypti, in addition to its role in immature stages, juvenile hormone III (JH) governs post-eclosion (PE) development in adult females, a phase required for competence acquisition for blood feeding and subsequent egg maturation. During PE, JH through its receptor Methoprene-tolerant (Met) regulate the expression of many genes, causing either activation or repression. Met-mediated gene repression is indirect, requiring involvement of intermediate repressors. Hairy, which functions downstream of Met in the JH gene-repression hierarchy, is one such factor. Krüppel-homolog 1, a zinc-finger transcriptional factor, is directly regulated by Met and has been implicated in both activation and repression of JH-regulated genes. However, the interaction between Hairy and Kr-h1 in the JH-repression hierarchy is not well understood. Our RNAseq-based transcriptomic analysis of the Kr-h1-depleted mosquito fat body revealed that 92% of Kr-h1 repressed genes are also repressed by Met, supporting the existence of a hierarchy between Met and Kr-h1 as previously demonstrated in various insects. Notably, 130 genes are co-repressed by both Kr-h1 and Hairy, indicating regulatory complexity of the JH-mediated PE gene repression. A mosquito Kr-h1 binding site in genes co-regulated by this factor and Hairy was identified computationally. Moreover, this was validated using electrophoretic mobility shift assays. A complete phenocopy of the effect of Met RNAi depletion on target genes could only be observed after Kr-h1 and Hairy double RNAi knockdown, suggesting a synergistic action between these two factors in target gene repression. This was confirmed using a cell-culture-based luciferase reporter assay. Taken together, our results indicate that Hairy and Kr-h1 not only function as intermediate downstream factors, but also act together in a synergistic fashion in the JH/Met gene repression hierarchy.

4.
Food Funct ; 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31664284

RESUMO

The roots of Polygala tenuifolia Willd have a long history of being used as a traditional Chinese medicine for the treatment of insomnia, forgetfulness, sorrow and depression. Tenuifolin (TEN) has been isolated from Polygala tenuifolia Willd roots, and this study was carried out to investigate the potential beneficial effects of TEN on neuronal apoptosis and memory deficits in a mouse model of Alzheimer's disease (AD). TEN treatment reversed spatial learning and memory deficits, as well as neuronal apoptosis in hippocampal areas, in APP/PS1 transgenic AD mice. TEN treatment protected against Aß25-35-induced apoptosis, loss of mitochondria-membrane potential, and activation of caspases-3 and -9 in SH-SY5Y cells. TEN has potential benefit in treating learning and memory deficits in APP/PS1 transgenic AD mice, and its effects may be associated with reversing AD pathology-induced neuronal apoptosis. These insights pave the way for further analysis of the potential of TEN as an AD therapeutic agent.

5.
Arch Insect Biochem Physiol ; : e21629, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31599031

RESUMO

Parasitoids serve as effective biocontrol agents for agricultural pests. However, they face constant challenges from host immune defense and numerous pathogens and must develop potent immune defense against these threats. Despite the recent advances in innate immunity, little is known about the immunological mechanisms of parasitoids. Here, we identified and characterized potential immune-related genes of the endoparasitoid, Pteromalus puparum, which act in regulating populations of some members of the Pieridae. We identified 216 immune-related genes based on interrogating the P. puparum genome and transcriptome databases. We categorized the cognate gene products into recognition molecules, signal moieties and effector proteins operating in four pathways, Toll, IMD, JAK/STAT, and JNK. Comparative analyses of immune-related genes from seven insect species indicate that recognition molecules and effector proteins are more expanded and diversified than signaling genes in these signal pathways. There are common 1:1 orthologs between the endoparasitoid P. puparum and its relative, the ectoparasitoid Nasonia vitripennis. The developmental expression profiles of immune genes randomly selected from the transcriptome analysis were verified by a quantitative polymerase chain reaction. Our work provides comprehensive analyses of P. puparum immune genes, some of which may be exploited in advancing parasitoid-based biocontrol technologies.

6.
Biomed Pharmacother ; 120: 109520, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31629251

RESUMO

OBJECTIVE: To investigate the effect and underlying mechanism of Yougui pills (YGPs) on steroid-related osteonecrosis of the femoral head (SONFH). METHODS: Male New Zealand white rabbits were divided into three groups: control group, SONFH group and YGPs group. Rabbit SONFH was induced by methylprednisolone (MPS) combined with lipopolysaccharide (LPS). At 6 weeks post induction, the femoral heads were harvested for tissue analyses, including histopathology, mechanical test of femoral heads, micro-CT, tartrate-resistant acid phosphatase (TRAP) staining, and immunohistochemistry for osteocalcin (OCN), vascular endothelial growth factor (VEGF) and ß-catenin. Protein levels of cathepsin K (CTSK), phospho-glycogen synthase kinase-3 beta (p-Ser9 GSK-3ß) and total glycogen synthase kinase-3 beta (GSK-3ß) in femoral heads were also detected. Additionally, the serum TRAP activity was measured using enzyme-linked immunosorbent assay (ELISA). Finally, the effects of YGPs treatment on osteoclast differentiation and osteoblast formation were evaluated in vitro. RESULTS: The ratio of empty lacuna was markedly lower in YGPs group than SONFH group. Micro-CT evaluation indicated that YGPs has a preventive effect on bone loss in rabbit SONFH. YGPs treatment could suppress bone resorption by reducing TRAP+ osteoclast and serum TRACP5b levels in necrotic femoral heads. Moreover, YGPs treatment could promote bone formation by up-regulating the expression of OCN, VEGF and ß-catenin, while increasing load-bearing capacity of femoral heads. Interestingly, p-Ser9 GSK-3ß downregulation, and CTSK upregulation in necrotic femoral head could be reversed by YGPs treatment, which also effectively inhibited RANKL-induced osteoclast differentiation and promoted osteoblast formation in vitro. CONCLUSION: YGPs could suppress osteoclastogenesis and promote bone formation during SONFH in rabbits by activating ß-catenin.

7.
Analyst ; 144(21): 6254-6261, 2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31560359

RESUMO

As VEGF mRNA is an endothelial cell-specific mitogen and a key regulator of angiogenesis in a variety of physiological and pathological processes, high expression levels of VEGF messenger RNA (mRNA) contribute to VEGF-driven angiogenesis in the hypoxic areas of solid tumors and then disrupt the vascular barrier, which may potentiate tumor cell extravasation. Thus, monitoring the changes in VEGF mRNA is necessary to understand the genetic programme under hypoxic conditions and thus facilitate risk assessment and risk reduction in hypoxic environments. Herein, a new fluorescent nanoprobe based on azoreductase-responsive functional metal-organic frameworks (AMOFs) was developed to realize the imaging of VEGF mRNA under hypoxic conditions. Since the azobenzene units in the AMOFs can be reduced to amines by the highly expressed azoreductase in an oxygen-deficient environment, the VEGF mRNA-targeted molecular beacon (MB), which is adsorbed on the surface of AMOFs via electrostatic interactions, can be released due to the structural damage of AMOFs. Moreover, TAMRA (carboxytetramethylrhodamine, donor) and Cy5 (acceptor) were close to each other due to the stem-loop conformation of MB, thus inducing high fluorescence energy resonance transfer (FRET) efficiency. Upon the addition of VEGF mRNA, the hybridization of VEGF mRNA destroyed the stem-loop conformation of MB, and then, the two fluorophores labeled on MB were separated with low FRET efficiency. This constructed fluorescent nanoprobe enables the quantitative analysis and in situ imaging of the VEGF mRNA level in living cells under hypoxic conditions. We expect that it will offer a potentially rich opportunity to understand the physiological processes of genetic programme.

8.
Life Sci ; 233: 116741, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31398419

RESUMO

AIMS: Carbon black nanoparticles (CBNPs) are widely used in industrial field. Sensitive stages such as pregnancy are assumed to be more susceptible to stimulus, however whether pregnancy exposure to CBNPs (PrE-to-CBNPs) would cause long-term toxic effects in dams and the underlying mechanisms remain poorly addressed. The present study is aimed to determine the long-term toxic effects of PrE-to-CBNPs in dams. MATERIALS AND METHODS: The pregnant mice were randomly divided into control group, low (21 µg/animal), medium (103 µg/animal) and high (515 µg/animal) CBNPs-treated groups. From gestational day (GD) 9 to GD18, the pregnant mice were intranasal exposed. At 49 days after parturition, lung tissues and bronchoalveolar lavage fluid (BALF) were obtained. Weight change, lung histopathology, lung ultrastructural pathology, cell count in BALF, oxidative stress/inflammatory maker and autophagy/lysosome-related protein expression were determined. KEY FINDINGS: PrE-to-CBNPs caused a dose-dependent persistent lung injury in mice even 49 days after parturition, including the deteriorative lung histopathological changes, elevation of oxidative stress marker Nrf-2, HO-1 and CHOP, infiltration of macrophage and increased mRNA expression of inflammatory cytokines in the lung tissues and elevation of cells in BALF. However, PrE-to-CBNPs did not induce significant neutrophil infiltration and fibrosis. Moreover, we found that CBNPs could deposit in the lysosomes and decrease cathepsin D (an important hydrolase in lysosome), which might be associated with the dysfunction of lysosome and autophagy. SIGNIFICANCE: Our study demonstrated that PrE-to-CBNPs could result in long-term lung injury in dams, and lysosomal dysfunction was probably linked to this process.


Assuntos
Inflamação/complicações , Lesão Pulmonar/etiologia , Lisossomos/patologia , Nanopartículas/efeitos adversos , Estresse Oxidativo , Efeitos Tardios da Exposição Pré-Natal/etiologia , Fuligem/efeitos adversos , Animais , Autofagia , Citocinas/metabolismo , Feminino , Lesão Pulmonar/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Gravidez , Efeitos Tardios da Exposição Pré-Natal/patologia
9.
Sci Adv ; 5(8): eaav9801, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31457079

RESUMO

A parasite-infected host may promote performance of associated insect vectors; but possible parasite effects on nonvector insects have been largely unexplored. Here, we show that Begomovirus, the largest genus of plant viruses and transmitted exclusively by whitefly, reprogram plant immunity to promote the fitness of the vector and suppress performance of nonvector insects (i.e., cotton bollworm and aphid). Infected plants accumulated begomoviral ßC1 proteins in the phloem where they were bound to the plant transcription factor WRKY20. This viral hijacking of WRKY20 spatiotemporally redeployed plant chemical immunity within the leaf and had the asymmetrical benefiting effects on the begomoviruses and its whitefly vectors while negatively affecting two nonvector competitors. This type of interaction between a parasite and two types of herbivores, i.e., vectors and nonvectors, occurs widely in various natural and agricultural ecosystems; thus, our results have broad implications for the ecological significance of parasite-vector-host tripartite interactions.

10.
J Biomed Nanotechnol ; 15(9): 1867-1880, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31387675

RESUMO

The present study aims to evaluate the effect of the ethyl acetate extract of Cichorium (EAEC) as a novel photosensitizer in photodynamic therapy (PDT) of colorectal carcinoma (CRC) HCT116 and SW620 cells. The absorption and fluorescence spectra of EAEC were measured using a UV-vis spectrophotometer and fluorescence spectrophotometer, respectively. EAEC-induced reactive oxygen species (ROS) production in HCT116 and SW620 cells was detected using 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA) and glutathione/glutathione disulfide (GSH/GSSG). The photo- and dark toxicities of EAEC were estimated using the Cell Counting Kit-8 (CCK-8) assay. Cellular uptake and localization of EAEC were detected by confocal laser fluorescence microscopy. Annexin V-FITC/PI staining, Western blotting and immunofluorescence staining were used to assess apoptosis and autophagy. The antitumor activity of EAEC was confirmed in a xenograft model. Finally, effects on the PERK pathway were verified using qRT-PCR and Western blotting. EAEC displayed absorption and fluorescence emission peaks at 660 nm and 678 nm, respectively. EAEC induced ROS production in CRC cells. Assessment of dark toxicity showed that treatment with EAEC alone induced little cytotoxicity in CRC or normal cells but that EAEC-PDT induced significant photocytotoxicity in CRC cells in a time- and dose-dependent manner. After cellular uptake, EAEC was located in the mitochondria. Treatment with EAEC-PDT reduced xenograft tumor size. Further evaluation suggested that activation of the PERK pathway mediates these effects, as the apoptotic rate and autophagy flux increased markedly after EAEC-PDT. EAEC, a natural photosensitizer extracted from Cichorium, displays potential utility in PDT of CRC by targeting the PERK pathway.


Assuntos
Autofagia , Neoplasias Colorretais , Fotoquimioterapia , Acetatos , Apoptose , Linhagem Celular , Linhagem Celular Tumoral , Estresse do Retículo Endoplasmático , Humanos , Fármacos Fotossensibilizantes , Proteínas Quinases , Espécies Reativas de Oxigênio
11.
Insect Sci ; 2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31317624

RESUMO

Recently, parasitoid wasp species Microplitis mediator has evoked increasing research attention due to its possible use in the control of Lepidoptera insects. Because insect development involves changes in cuticle composition, identification and expression analysis of M. mediator cuticular proteins may clarify the mechanisms involved in parasite development processes. We found 70 cuticular proteins from the M. mediator transcriptome and divided them into seven distinct families. Expression profiling indicated that most of these cuticular protein genes have expression peaks specific for one particular developmental stage of M. mediator. Eggs and pupae have the highest number of transcriptionally active cuticular protein genes (47 and 52 respectively). Only 12 of these genes maintained high expression activity during late larval development. Functional analysis of two larval proteins, MmCPR3 and MmCPR14, suggested their important role in the proper organization of the cuticle layers of larvae. During M. mediator larval development, normal cuticle formation can be supported by a limited number of cuticular proteins.

12.
Toxicology ; 425: 152244, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31302203

RESUMO

Accumulating evidence shows that carbon black nanoparticles (CBNPs) (one of the most used nanoparticles) can induce toxicity via induction of inflammation, oxidative stress and genotoxicity in vitro and in vivo, and epidemiological studies have indicated that the possible correlation between maternal immune activation and risk of developing neuropsychiatric disorder in the offspring. However, whether pregnancy exposure of CBNPs (Pr-CBNPs) enhances the susceptibility to bleomycin (BLM)-induced lung fibrosis in offspring is unknown. Herein, we demonstrated that Pr-CBNPs during gestational day 9-18 via intranasal administration could confer enhanced susceptibility to BLM-induced fibrotic response in offspring, including deteriorative lung pathologic changes and more collagen deposition. Intriguingly, we found that Pr-CBNPs repressed the activation of autophagy (an anti-fibrotic mechanism), which was moderately activated in offspring from mock group. Moreover, Pr-CBNPs was likely to disrupt the LKB1-AMPK-ULK1 axis (a key regulatory pathway for autophagy induction). In summary, this study provides the first evidence that pregnancy exposure to CBNPs can exacerbate BLM-induced lung fibrotic response in offspring probably through disruption of LKB1-AMPK-ULK1 axis-mediated autophagy.

13.
Mikrochim Acta ; 186(8): 565, 2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31338677

RESUMO

A colorimetric and visual assay is described for the herbicide aminotriazole (ATZ). It is based on the etching of gold nanorods (AuNRs) by iodine which is formed on oxidation of iodide via H2O2. Longitudinal etching of the AuNRs occurs quickly and is accompanied by a color change from dark blue to red. In the absence of ATZ and the presence of active catalase (CAT), H2O2 is quickly decomposed into water, and the AuNRs will not be etched. In the presence of ATZ, CAT is partially deactivated, and this affects the amount of available H2O2 and, consequently, of the iodine. Hence, the color is significantly changed. The color changes can be easily detected with bare eyes. The assay has a linear response in the 5 to 70 µM concentration range, with a detection limit of 1.3 µM and high selectivity for ATZ. It was applied to the determination of ATZ in water and food samples. Graphical abstract A multicolor colorimetric method is developed for aminotriazole (ATZ) detection based on catalase (CAT) deactivation-dependent longitudinal etching of gold nanorods (AuNRs). The color signals can be visually identified. Good detection performances and capability for evaluating ATZ level in water and food samples is demonstrated.

14.
Nat Commun ; 10(1): 2756, 2019 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-31227702

RESUMO

Flight loss in birds is as characteristic of the class Aves as flight itself. Although morphological and physiological differences are recognized in flight-degenerate bird species, their contributions to recurrent flight degeneration events across modern birds and underlying genetic mechanisms remain unclear. Here, in an analysis of 295 million nucleotides from 48 bird genomes, we identify two convergent sites causing amino acid changes in ATGLSer321Gly and ACOT7Ala197Val in flight-degenerate birds, which to our knowledge have not previously been implicated in loss of flight. Functional assays suggest that Ser321Gly reduces lipid hydrolytic ability of ATGL, and Ala197Val enhances acyl-CoA hydrolytic activity of ACOT7. Modeling simulations suggest a switch of main energy sources from lipids to carbohydrates in flight-degenerate birds. Our results thus suggest that physiological convergence plays an important role in flight degeneration, and anatomical convergence often invoked may not.


Assuntos
Evolução Biológica , Aves/fisiologia , Metabolismo Energético/genética , Voo Animal/fisiologia , Genoma/genética , Animais , Metabolismo dos Carboidratos/fisiologia , Genômica/métodos , Lipase/genética , Lipase/metabolismo , Lipólise/fisiologia , Palmitoil-CoA Hidrolase/genética , Palmitoil-CoA Hidrolase/metabolismo , Filogenia
15.
Anal Chem ; 91(13): 8574-8581, 2019 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-31247722

RESUMO

Mitophagy, as an evolutionarily conserved cellular process, plays a crucial role in preserving cellular metabolism and physiology. Various microenvironment alterations assigned to mitophagy including pH, polarity, and deregulated biomarkers are increasingly understood. However, mitophagy-specific viscosity dynamic in live cells remains a mystery and needs to be explored. Here, a water-soluble mitochondria-targetable molecular rotor, ethyl-4-[3,6-bis(1-methyl-4-vinylpyridium iodine)-9 H-carbazol-9-yl)] butanoate (BMVC), was exploited as a fluorescent viscosimeter for imaging viscosity variation during mitophagy. This probe contains two positively charged 1-methyl-4-vinylpyridium components as the rotors, whose rotation will be hindered with the increase of environmental viscosity, resulting in enhancement of fluorescence emission. The results demonstrated that this probe operates well in a mitochondrial microenvironment and displays an off-on fluorescence response to viscosity. By virtue of this probe, new discoveries such as the mitochondrial viscosity will increase during mitophagy are elaborated. The real-time visualization of the mitophagy process under nutrient starvation conditions was also proposed and actualized. We expect this probe would be a robust tool in the pathogenic mechanism research of mitochondrial diseases.

16.
Chem Commun (Camb) ; 55(45): 6433-6436, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31095138

RESUMO

Herein, we developed a versatile strategy for the synchronous screening of biomarkers of Alzheimer's disease (AD) by incorporating the high-resolution discrimination of an aerolysin nanopore to length-encoded oligonucleotides and the signal transduction of a triple-helix molecular switch (TMS). This assay is adapted to quantitatively compare multiplexed targets of very different native contents without tedious chemical labelling.


Assuntos
Doença de Alzheimer/diagnóstico , Toxinas Bacterianas/química , Nanoporos , Proteínas Citotóxicas Formadoras de Poros/química , Biomarcadores/análise , Humanos
17.
Nat Prod Res ; : 1-7, 2019 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-31109181

RESUMO

Three new biflavones, apigenin-(3',8″)-chrysin (1), (2S)-2,3-Dihydroametoflavone 5,4'-dimethyl ether (2), and (2S)-5″,7″-Dihydroxy-2″-phenoxychromonyl-(4'″,3')-naringenin (3), together with seven known biflavones (4-10) were isolated from the 75% EtOH extract of Selaginella doederleinii. The structures of new compounds were established by application of spectroscopic methods, including 1D and 2D NMR, HRMS, and CD measurements. In addition, all new compounds were evaluated for their cytotoxic potential against three human cancer cell lines A549, MCF-7, and SMMC-7721 in vitro. Compound 2 exhibited potent cytotoxic activity with IC50 values ranging from 6.35 to 10.18 µM.

18.
Biosens Bioelectron ; 137: 96-109, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31085403

RESUMO

During the last decades, by virtue of their unique physicochemical properties and potential application in microelectronics, biosensing and biomedicine, metal nanomaterials (MNs) have attracted great research interest and been highly developed. Deoxyribonucleic acid (DNA) is a particularly interesting ligand for templating bottom-up nanopreparation, by virtue of its excellent properties including nanosized geometry structure, programmable and artificial synthesis, DNA-metal ion interaction and powerful molecular recognition. DNA-templated copper nanoparticles (DNA-CuNPs) has been developed in recent years. Because of its advantages including simple and rapid preparation, high efficiency, MegaStokes shifting and low biological toxicity, DNA-CuNPs has been highly exploited for biochemical sensing from 2010, especially as a label-free detection manner, holding advantages in multiple analytical technologies including fluorescence, electrochemistry, surface plasmon resonance, inductively coupled plasma mass spectrometry and surface enhanced Raman spectroscopy. This review comprehensively tracks the preparation of DNA-CuNPs and its application in biosensing, and highlights the potential development and challenges regarding this field, aiming to promote the advance of this fertile research area.

19.
Philos Trans R Soc Lond B Biol Sci ; 374(1767): 20180323, 2019 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-30967022

RESUMO

Reactive oxygen species (ROS) play important roles in defence response of host plants versus pathogens. While generation and detoxification of ROS is well understood, how varied ability of different isolates of pathogens to overcome host ROS, or ROS contribution to a particular isolate's pathogenicity, remains largely unexplored. Here, we report that transcriptional regulation of the ROS pathway, in combination with the insulin pathway, increases the pathogenicity of invasive species Bursaphelenchus xylophilus. The results showed a positive correlation between fecundity and pathogenicity of different nematode isolates. The virulent isolates from introduced populations in Japan, China and Europe had significantly higher fecundity than native avirulent isolates from the USA. Increased expression of Mn-SOD and reduced expression of catalase/ GPX-5 and H2O2 accumulation during invasion are associated with virulent strains. Additional H2O2 could improve fecundity of Bu. xylophilus. Furthermore, depletion of Mn-SOD decreased fecundity and virulence of Bu. xylophilus, while the insulin pathway is significantly affected. Thus, we propose that destructive pathogenicity of Bu. xylophilus to pines is partly owing to upregulated fecundity modulated by the insulin pathway in association with the ROS pathway and further enhanced by H2O2 oxidative stress. These findings provide a better understanding of pathogenic mechanisms in plant-pathogen interactions and adaptive evolution of invasive species. This article is part of the theme issue 'Biotic signalling sheds light on smart pest management'.

20.
Toxicology ; 422: 44-52, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-31022427

RESUMO

Maternal exposure to carbon black nanoparticles (CBNPs) during pregnancy have been well documented to induce harmful outcomes of offspring on brain function. However, it remains largely unknown whether females exposed to CBNPs during sensitive period of pregnancy can cause the neurotoxic effects on their own body after parturition. In this study, our results showed that pregnancy CBNPs exposure induced the persistent pathological changes in the cerebral cortex tissues and impaired cerebrovascular function of mice manifested by significant alterations of endothelin-1, endothelial nitric oxide synthase, vascular endothelial growth factor-A and ATP-binding cassette transporter G1. Intriguingly, we observed that these deleterious effects on brain and cerebrovascular functions in mice could persist for 49 days after delivery of pups. By using in vitro human umbilical vein endothelial cells, we further verified the potential vascular dysfunction after CBNPs exposure. In summary, our results provide the first evidence that pregnancy CBNPs exposure-induced brain pathological changes and cerebrovascular dysfunction can persist for a relative long time. These finding suggest exposure to CBNPs during sensitive stages of pregnancy may not only show the harmful effects on offspring neurodevelopment, but also result in the irreversible brain damage on mother body.

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