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1.
J Steroid Biochem Mol Biol ; 199: 105597, 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31958634

RESUMO

Sex steroid hormones play important roles in fish sex differentiation, gonadal development and secondary sexual characteristics. Olive flounder Paralichthys olivaceus is a valuable commercial marine fish species and has marked sexual dimorphism. However, the mechanisms of action of sex hormones in flounder sex are still unclear. In this study, a total of ten Hsd17b family genes, including Hsd17b3, -4, -7, -8, -9, -10, -12a, -12b, -14 and -15, were identified in the flounder, which encoded critical enzymes acting on sex steroid synthesis and metabolism. Hsd17b genes were distributed on eight chromosomes. Hsd17b12a and -12b were located on chromosomes 19 and 7, respectively. It was speculated that these two genes were just highly similar rather than different transcripts derived from the same gene. According to the results of domain and motif analyses, they all belonged to the SDR superfamily and contained conserved Hsd17b motifs TGxxxGxG, PGxxxT, NNAG and YxxxK. Analysis of amino acid sequences predicted that Hsd17b1, -4, -7, -12a and -14 were hydrophilic proteins. The stability of Hsd17b1, -3 and -12b proteins was predicted to be low. The various Hsd17b family genes differed in tissue expression pattern, and Hsd17b10, -12a and -12b were highly expressed in the flounder ovary. Moreover, throughout gonadal development, Hsd17b3 was highly expressed in the testis, and Hsd17b1, -12a and -12b were highly expressed in the ovary, suggesting that they might play an important role in testosterone synthesis in the testis or estrogen synthesis in the ovary. Activities of Hsd17b3 at stages I-V were all significantly higher in the testis than in the ovary (P < 0.05, P < 0.01). Transfection analysis in HEK293T cells showed that Hsd17b1 and -3 were located in both the cytoplasm and nucleus. Additionally, after challenging fish with tamoxifen, Hsd17b3 expression level in the testis decreased significantly (P < 0.01), and in the ovary no significant change was observed. Moreover, the expression of Hsd17b1 in the ovary was significantly upregulated after injection with flutamide (P < 0.05). These findings introduce the characteristics of the flounder Hsd17b in subfamily, which contribute to our understanding of the regulation of sex steroid hormone synthesis in fish gonadal development.

2.
Sci Rep ; 10(1): 171, 2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31932615

RESUMO

Quantum key distribution (QKD) generates symmetric keys between two authenticated parties with the guarantee of information-theoretically security. A vital step in QKD to obtain fully-matched key between two parties is information reconciliation. The blind reconciliation protocol provides a useful tool that corrects the mismatch in a wide range of qubit error rate (QBER) but without a prior error estimation. However, there is a contradiction between the reconciliation efficiency and the processing time in this protocol. In this work, we propose a blind reconciliation protocol with variable step sizes to relieve this contradiction. The analysis and simulation results show that the improved protocol inherits all the advantages of the original blind reconciliation protocol and can obtain better reconciliation efficiency with less operation time. The improved blind reconciliation protocol enhances the final secret key rate and accelerates the processing speed of a QKD system.

3.
Mol Cancer Ther ; 19(2): 490-501, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31911530

RESUMO

In recent years, HER3 has increasingly been implicated in the progression of a variety of tumor types and in acquired resistance to EGFR and HER2 therapies. Whereas EGFR and HER2 primarily signal through the MAPK pathway, HER3, as a heterodimer with EGFR or HER2, potently activates the PI3K pathway. Despite its critical role, previous attempts to target HER3 with neutralizing antibodies have shown disappointing efficacy in the clinic, most likely due to suboptimal and indirect mechanisms of action that fail to completely block heterodimerization; for example, tumors can escape inhibition of ligand binding by upregulating ligand-independent mechanisms of HER3 activation. We therefore developed 10D1F, a picomolar affinity, highly specific anti-HER3 neutralizing antibody that binds the HER3 heterodimerization interface, a region that was hitherto challenging to raise antibodies against. We demonstrate that 10D1F potently inhibits both EGFR:HER3 and HER2:HER3 heterodimerization to durably suppress activation of the PI3K pathway in a broad panel of tumor models. Even as a monotherapy, 10D1F shows superior inhibition of tumor growth in the same cell lines both in vitro and in mouse xenograft experiments, when compared with other classes of anti-HER3 antibodies. This includes models demonstrating ligand-independent activation of heterodimerization as well as constitutively activating mutations in the MAPK pathway. Possessing favorable pharmacokinetic and toxicologic profiles, 10D1F uniquely represents a new class of anti-HER3 neutralizing antibodies with a novel mechanism of action that offers significant potential for broad clinical benefit.10D1F is a novel anti-HER3 antibody that uniquely binds the receptor dimerization interface to block ligand-dependent and independent heterodimerization with EGFR/HER2 and thus more potently inhibits tumor growth than existing anti-HER3 antibodies.

4.
Mol Reprod Dev ; 87(1): 78-90, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31788912

RESUMO

Olive flounder (Paralichthys olivaceus) is a commercially important flatfish species cultured in East Asia. Female flounders generally grow more rapidly than males, therefore control of the sex ratio seems to be a proposed way to increase production. However, the sex determination gene and sex determination mechanism have yet been elucidated. The brain is an important organ that is involved in gonadal development. To explore the sex differences of gene expression in the brain before and during the flounder gonadal differentiation, we used messenger RNA (mRNA)-seq technology to investigate transcriptomes of male and female brains. Between female and male brains, 103 genes were differentially expressed before ovarian differentiation, 16 genes were differentially expressed before testicular differentiation, and 64 genes were differentially expressed during gonadal differentiation. According to annotation and Kyoto Encyclopedia of Genes and Genomes information, the differentially expressed genes (DEGs) were involved in circadian rhythm, circadian rhythm-fly, circadian entrainment, dopaminergic synapse, calcium signaling, glutamatergic synapse, taste transduction, herpes simplex infection, long-term depression, retrograde endocannabinoid signaling, and the synaptic vesicle cycle pathways. MicroRNA (miRNA)-seq was performed during the gonadal differentiation and the target genes of miRNAs were predicted. Integrated analysis of mRNA-seq and miRNA-seq showed that 29 of the 64 DEGs were regulated by the differentially expressed miRNAs during the gonadal differentiation. Our study provides a basis for further studies of brain sex differentiation and the molecular mechanism of sex determination in olive flounder.

5.
J Hazard Mater ; 384: 121251, 2020 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-31581007

RESUMO

Thermal desorption was an efficient method for removal of decabromodiphenyl ether (BDE-209) from contaminated soil, but some less brominated diphenyl ethers (tri- to hepta-BDEs) with high toxicity were detected in the effluent gas. Herein, a novel anodic alumina supported Fe-based catalyst was developed and applied for in-situ degradation of gaseous polybrominated diphenyl ethers (PBDEs). The produced Fe/γ-Al2O3/Al catalyst was able to degrade PBDEs in the effluent gas, while a low activity with degradation efficiency of 70.1% was observed. As such, Cu was added into the Fe-based catalyst, and the effects of Cu loading on gaseous PBDEs degradation were systematically examined. A proper copper loading was found to increase the active Fe3O4 sites, thus improving the catalytic activity. Meanwhile, the degradation of gaseous PBDEs by Fe-based catalysts follows a pseudo-first-order model. A 90.2% PBDEs degradation efficiency was achieved at 375 °C on the optimized Fe/Cu/γ-Al2O3/Al catalyst, which demonstrated that the anodic alumina supported Fe and Cu was an excellent catalyst for gaseous PBDEs degradation system. Thus, this study provides a promising method and catalyst to achieve in-situ degradation of gaseous PBDEs.

6.
Cancer Sci ; 111(1): 186-199, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31746077

RESUMO

Activity of transcriptional co-activator with PDZ binding domain (TAZ) protein is strongly implicated in the pathogenesis of human cancer and is influenced by tumor metabolism. High levels of lactate concentration in the tumor microenvironment as a result of metabolic reprogramming are inversely correlated with patient overall survival. Herein, we investigated the role of lactate in the regulation of the activity of TAZ and showed that glycolysis-derived lactate efficiently increased TAZ expression and activity in lung cancer cells. We showed that the reactive oxygen species (ROS) generated by lactate-fueled oxidative phosphorylation (OXPHOS) in mitochondria activated AKT and thereby inhibited glycogen synthase kinase 3 beta/beta-transducin repeat-containing proteins (GSK-3ß/ß-TrCP)-mediated ubiquitination and degradation of DNA methyltransferase 1 (DNMT1). Upregulation of DNMT1 by lactate caused hypermethylation of TAZ negative regulator of the LATS2 gene promoter, leading to TAZ activation. Moreover, TAZ binds to the promoter of DNMT1 and is necessary for DNMT1 transcription. Our study showed a molecular mechanism of DNMT1 in linking tumor metabolic reprogramming to the Hippo-TAZ pathway and functional significance of the DNMT1-TAZ feedback loop in the migratory and invasive potential of lung cancer cells.


Assuntos
DNA (Citosina-5-)-Metiltransferase 1/genética , Ácido Láctico/metabolismo , Estresse Oxidativo/genética , Transativadores/genética , Transcrição Genética/genética , Ativação Transcricional/genética , Linhagem Celular Tumoral , Glicogênio Sintase Quinase 3 beta/genética , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Regiões Promotoras Genéticas/genética , Ligação Proteica/genética , Espécies Reativas de Oxigênio/metabolismo
7.
Biochim Biophys Acta Mol Basis Dis ; 1866(1): 165576, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31666207

RESUMO

Highly expressed G protein-coupled receptor 81 (GPR81), a receptor for lactate, is emerging as a critical regulator of tumor growth and metastasis. However, the mechanistic basis for its highly expression in cancer cells remains elusive. Here we report that tumor-derived lactate transcriptionally regulates GPR81 expression. We demonstrated that the transcriptional response of GPR81 to lactate is mediated by Signal transducer and activator of transcription 3 (STAT3). Mechanistically, lactate upregulates transcriptional factor Snail and induces the assembly of Snail/EZH2/STAT3 complex. Within this ternary complex, STAT3 activity is strongly enhanced. Consequently, the activated STAT3 by lactate directly binds GPR81promoter and activates its expression. These findings shed light on the transcriptional mechanism by which GPR81 expression is regulated in cancer cells, and provides mechanistic insight into how aberrant signaling and continually high lactate levels due to metabolic switch may yield a feed-forward/self-enabling loop to promote tumor progression.

8.
Environ Sci Pollut Res Int ; 26(35): 35704-35716, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31701417

RESUMO

DGT (diffusive gradients in thin films) technique and LA-ICP-MS (laser ablation inductively coupled plasma mass spectrometry) for heterogeneous distribution of the soluble labile iron (Fe) at submillimeter resolution in lake sediment porewater are reported. The soluble labile Fe species include ion and labile organic complexes. The chemical images in two dimensions (2D) for DGT concentration of Fe (CDGT(Fe)) are investigated for Fe remobilization character. There are 902 CDGT(Fe) values between 1000 and 2000 µg L-1, 463 values between 2000 and 3000 µg L-1, and 112 values over 3000 µg L-1 in all chemical maps. Based on the linear correlation relationships between CDGT (Fe) and total Fe (TFe), total organic carbon (TOC), acid-volatile sulfide (AVS), Eh, concentrations of the soluble reactive phosphorus (P) (SRP), and soluble labile trace metals (Zn, Cu, Pb, and Zn) in a vertical 1D profile of sediment or porewater, Fe release mechanisms are mainly due to the reductive Fe release from iron oxyhydroxides and the decomposition of organic matter in algae biomass and deep sediment layer. It can be used to explain the formation mechanisms of Fe microniches in chemical maps with heterogeneous character to a great extent. CDGT(Fe) peak flux in the center of Fe microniche and the low CDGT (Fe) at the edge of a microniche are due to the formation of the insoluble iron sulfide and the abundant acid-volatile sulfide (AVS) in sediment. The verified co-remobilization of the soluble labile Fe and trace metals or SRP in sediment porewater can be used to predict their simultaneous release from Fe microniches with the large CDGT (Fe) peaks. The different kinds of Fe microniche zones and hot spots from sediment/water interface (SWI) to deep sediment correspond to the formation mechanisms of microniches mentioned above. Moreover, some narrow Fe microniche zones with the large CDGT (Fe) across chemical maps are due to the desorption of Fe(II) from the freshly formed oxide on Myriophyllum verticiilatur roots, which are located at sites of microniche zones.

9.
Anal Chim Acta ; 1091: 59-68, 2019 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-31679575

RESUMO

A facile ratiometric fluorescence method for ascorbic acid (AA) detection was established by combining the fluorescence of MoS2 quantum dots (QDs) with second-order scattering (SOS) of CoOOH. In MoS2 QDs/CoOOH nanohybrid system, the fluorescence of MoS2 QDs was quenched by CoOOH whereas the intensity of SOS was relatively close to the fluorescence due to the intrinsic high scattering ability of large size CoOOH nanoflakes. With the addition of AA, CoOOH nanoflakes were reduced to Co2+ accompanied the size decline and the disappearance of characteristic absorption in UV-vis spectrum, resulting in the fluorescence recovery and SOS fading. Thus, the ratiometric detection of AA was obtained through the opposite changes of fluorescence and SOS. Under optimized conditions, the detection limit of AA was 0.21 µmol L-1 with a linear range from 0.80 to 32.0 µmol L-1. Furthermore, the MoS2 QDs/CoOOH nanohybrid system was applied to the detection of AA in human serum samples and vitamin C tablets with satisfactory results.

10.
Environ Pollut ; 255(Pt 2): 113279, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31563787

RESUMO

A new sediment P release risk index (SPRRI) for "in-situ" phosphorus (P) release risk in lake sediment, is developed based on diffusive gradients in thin films (DGT) technique, DGT induced flux in sediments (DIFS) model and sediment properties. SPRRI includes three sub-indexes, which contain (1) the labile P pool size, (2) resupply constant (r) and desorption rate (Dspt rate) for P transfer and (3) the molar ratio between iron (Fe) in sequential extraction for sediment P by bicarbonate-dithionite (BD) and aluminum (Al) by NaOH (at 25 °C), i.e. BD(Fe)/Al[NaOH25] in sediment solid. The first sub-index considers P release from (i) sediment with NH4Cl-P+BD-P pool, i.e. the loosely sorbed P (NH4Cl-P) plus iron associated P (BD-P), or (ii) sediment with NH4Cl-P pool, respectively. The second and third sub-indexes reflect kinetic P desorption and resupply ability of solid phase, and the effect of P sequestration by Al hydroxide on P release, in turn. The inner relationship between SPRRI and sub-indexes, and their effects on P release risk are elucidated. SPRRI can be used to evaluate sediment P reactivity by five release risk ranks. For Lake Dianchi (China), P transfer dynamics, labile P pool, resupply ability and Al-P in sediment, and "external P-loading" control and affect P release risk in different regions, which is reflected by the spatial distribution map for SPRRI. The present SPRRI can be applied for lakes with (1) pH range varying from moderate acidity to weak alkalinity in waterbody and (2) NH4Cl-P or NH4Cl-P+BD-P pool in sediment solid.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos/química , Fósforo/análise , Poluentes Químicos da Água/análise , Alumínio/análise , Hidróxido de Alumínio , Bicarbonatos , China , Ferro/química , Cinética , Lagos/química , Modelos Químicos
11.
Reprod Fertil Dev ; 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31537253

RESUMO

As an important maricultured fish, the olive flounder Paralichthys olivaceus shows sex-dimorphic growth. Thus, the molecular mechanisms involved in sex control in P. olivaceus have attracted researchers' attention. Among the sex-related genes, forkhead box protein L2 (foxl2) exhibits significant sex-dimorphic expression patterns and plays an important role in fish gonad differentiation and development. The present study first investigated the expression levels and promoter methylation dynamics of foxl2 during flounder gonad differentiation under treatments of high temperature and exogenous 17ß-oestradiol (E2). During high temperature treatment, the expression of flounder foxl2 may be repressed via maintenance of DNA methylation. Then, flounder with differentiated testis at Stages I-II were treated with exogenous 5ppm E2 or 5ppm E2+150ppm trilostane (TR) to investigate whether exogenous sex hormones could induce flounder sex reversal. The differentiated testis exhibited phenotypic variations of gonadal dysgenesis with upregulation of female-related genes (foxl2 and cytochrome P450 family 19 subfamily A (cyp19a)) and downregulation of male-related genes (cytochrome P450 family 11 subfamily B member 2 (cyp11b2), doublesex- and mab-3 related transcription factor 1 (dmrt1), anti-Mullerian hormone (amh) and SRY-box transcription factor 9 (sox9)). Furthermore, a cotransfection assay of the cells of the flounder Sertoli cell line indicated that Foxl2 was able alone or with nuclear receptor subfamily 5 group A member 2 (Nr5a2) jointly to upregulate expression of cyp19a. Moreover, Foxl2 and Nr5a2 repressed the expression of dmrt1. In summary, Foxl2 may play an important role in ovarian differentiation by maintaining cyp19a expression and antagonising the expression of dmrt1. However, upregulation of foxl2 is not sufficient to induce the sex reversal of differentiated testis.

12.
ACS Appl Mater Interfaces ; 11(35): 31991-31996, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31407887

RESUMO

A LiNi0.8Co0.15Al0.05O2 (NCA) solid battery was assembled by coupling an NCA cathode with a polyvinylidene fluoride (PVDF)/Li6.75La3Z1.75Ta0.25O12 (LLZTO) composite polymer electrolyte and a Li anode. A NiO-like phase transition is regarded as the reason for interface impedance, which leads to drastic capacity fading during cycling. A gradient cathode with excessive addition of Li6.75La3Zr1.75Ta0.25O12 was fabricated at the cathode/electrolyte interface to overcome the increased impedance. Using high-resolution transmission electron microscopy and electron energy loss spectra, the formation of a unique localized cation migration (LCM) region was confirmed on the NCA surface. The formation of an LCM region hindered further distortion and enhanced the capacity retention of the spinel lattice.

13.
Mol Cell ; 75(4): 835-848.e8, 2019 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-31378462

RESUMO

Mitochondrial dysfunction and proteostasis failure frequently coexist as hallmarks of neurodegenerative disease. How these pathologies are related is not well understood. Here, we describe a phenomenon termed MISTERMINATE (mitochondrial-stress-induced translational termination impairment and protein carboxyl terminal extension), which mechanistically links mitochondrial dysfunction with proteostasis failure. We show that mitochondrial dysfunction impairs translational termination of nuclear-encoded mitochondrial mRNAs, including complex-I 30kD subunit (C-I30) mRNA, occurring on the mitochondrial surface in Drosophila and mammalian cells. Ribosomes stalled at the normal stop codon continue to add to the C terminus of C-I30 certain amino acids non-coded by mRNA template. C-terminally extended C-I30 is toxic when assembled into C-I and forms aggregates in the cytosol. Enhancing co-translational quality control prevents C-I30 C-terminal extension and rescues mitochondrial and neuromuscular degeneration in a Parkinson's disease model. These findings emphasize the importance of efficient translation termination and reveal unexpected link between mitochondrial health and proteome homeostasis mediated by MISTERMINATE.


Assuntos
Códon de Terminação , Proteínas de Drosophila/metabolismo , Mitocôndrias/metabolismo , Doenças Mitocondriais/metabolismo , Proteínas Mitocondriais/metabolismo , Deficiências na Proteostase/metabolismo , Animais , Proteínas de Drosophila/genética , Drosophila melanogaster , Células HeLa , Humanos , Mitocôndrias/genética , Mitocôndrias/patologia , Doenças Mitocondriais/genética , Doenças Mitocondriais/patologia , Proteínas Mitocondriais/genética , Deficiências na Proteostase/genética , Deficiências na Proteostase/patologia , RNA Mitocondrial/genética , RNA Mitocondrial/metabolismo
14.
ACS Appl Mater Interfaces ; 11(27): 24560-24570, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31250630

RESUMO

The recovery of precious metals like palladium (Pd) from secondary resources has enormous economic benefits and is in favor of resource reuse. In this work, we prepared a high efficiency pyridine-functionalized reduced graphene oxide (rGO) adsorbent for selective separation of Pd(II) from simulated electronic waste leachate, by one-pot γ-ray radiation-induced simultaneous grafting polymerization (RIGP) of 4-vinylpyridine (4VP) from graphene oxide (GO) and reduction of GO. The poly(4-vinylpyridine)-grafted reduced graphene oxide (rGO-g-P4VP) exhibits fast adsorption kinetics and high maximum adsorption capacity. The adsorption capacity is 105 mg g-1 in the first minute and reaches equilibrium within 120 min. The adsorption process follows the Langmuir model, from which the maximum adsorption capacity of Pd(II) is estimated to be 177 mg g-1. We also proved that the adsorption mechanism of Pd(II) on rGO-g-P4VP involves both ion exchange and coordination adsorption by XPS analysis. Most importantly, the loss of oxygen-containing groups due to reduction of GO not only facilitates the separation of adsorbent from aqueous solution but also reduces the electrostatic repulsion toward Pd(II)Cl42- in hydrochloric acid solution, leading to a higher adsorption selectivity of Pd(II) over some common metal cations in electronic waste including Fe(III), Cu(II), and Al(III) compared with poly(4-vinylpyridine)-grafted graphene oxide (GO-g-P4VP) prepared by atom transfer radical polymerization. Other precious metals like Pt(IV) and Au(III) can also be recovered easily and selectively by rGO-g-P4VP. This work demonstrates that rGO-g-P4VP prepared by the facile RIGP is a promising adsorbent for recovery of precious metals from secondary resources like electronic waste leachate.

15.
Biomaterials ; 214: 119226, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31174068

RESUMO

Bacteria-driven drug-delivery systems have attracted great attention for their enhanced therapeutic specificity and efficacy in cancer treatment. YB1, a particularly attractive genetically modified safe Salmonella Typhimurium strain, is known to penetrate hypoxic tumor cores with its self-driven properties while remarkably avoiding damage to normal tissues. Herein, nanophotosensitizers (indocyanine green (ICG)-loaded nanoparticles, INPs) were covalently attached to the surface of YB1 with amide bonds to develop a biotic/abiotic cross-linked system (YB1-INPs) for tumor precision therapy. YB1 microswimmer retained its viability after efficiently linking with INPs. This YB1-INPs treatment strategy demonstrated specific hypoxia targeting to solid tumors, perfect photothermal conversion, and efficient fluorescence (FL) imaging properties. Benefited from the combined contribution of tumor tissue destruction and the bacteria-attracting nutrients generation after photothermal treatment, the bioaccumulation of YB1-INPs was significantly improved 14-fold compared to no photothermal intervention. Furthermore, YB1-INPs pervaded throughout the large solid tumor (≥500 mm3). Under near-infrared (NIR) laser irradiation, YB1-INPs exhibited a dependable and highly efficient photothermal killing ability for eradicating the large solid tumor without relapse. This strategy of bacteria-driven hypoxia-targeting delivery has a great value for large solid tumors therapy with low toxicity and high efficiency.

16.
Ecotoxicol Environ Saf ; 180: 632-645, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31132559

RESUMO

Increasing concentrations of metals in soil have posed a serious threat to the soil environment. The control and evaluation of soil metal hazards demand the establishment of soil ecological criteria, which is mainly based on the obtainment of toxicity thresholds. As the most typical representative of soil-dwelling springtails, Folsomia candida performs numerous essential ecological functions in soil and has been extensively used to investigate metal toxicity effects and thresholds. This review outlined the current state of knowledge on the metal toxicity thresholds to Folsomia candida, including (1) toxicity thresholds of soil metals for the different endpoints, (2) the influence factors of metal toxicity thresholds including the test conditions, the chemical forms of metal, the soil physicochemical properties, aging time and leaching, (3) the bioavailable fractions predicting metal toxicity thresholds, (4) the internal threshold of metals. To conclude, several recommendations for future research are given to obtain the more reliable toxicity thresholds and further supplement the toxicity data of metals to Folsomia candida.


Assuntos
Artrópodes/efeitos dos fármacos , Biomarcadores Ambientais/efeitos dos fármacos , Metaloides/toxicidade , Metais/toxicidade , Poluentes do Solo/toxicidade , Animais , Artrópodes/fisiologia , Disponibilidade Biológica , Relação Dose-Resposta a Droga , Biomarcadores Ambientais/fisiologia , Metaloides/farmacocinética , Metais/farmacocinética , Solo/química , Poluentes do Solo/farmacocinética , Testes de Toxicidade
17.
Ecotoxicol Environ Saf ; 174: 475-483, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-30856559

RESUMO

Nickel (Ni) is a toxic metal, but studies on Ni toxicity to soil-dwelling springtail are fairly limited, and did not consider the effects of various soil properties and long aging time. To address this, the chronic toxicity of Ni to model organism-Folsomia candida in relation to soil properties and aging time were evaluated in the laboratory study. The results showed that compared to the soils aged only for 7 d, the concentrations causing 50% mortality (LC50) and inhibiting 50% reproduction (EC50) basing measured total Ni in four soils aged for 120 d increased by 1.30-1.94 fold and 1.27-1.82 fold, respectively. Furthermore, the aging effects significantly correlated with soil pH. The toxicity values of Ni differed in ten soils aged for 120 d, the LC50 values were 279-4025 mg/kg and the EC50 values were 133-1148 mg/kg. When calculating the toxicity values basing water soluble and CaCl2 extracted Ni, the variations in LC50 values between ten soils decreased, while the variations in EC50 values increased. Regression analysis indicated that soil pH was the most important single factor predicting soil Ni toxicity to springtail, the combination of soil pH and OM could best explain Ni toxicity variance in ten soils (89.1% of the variance in LC50 values and 89.6% of the variance in EC50 values).


Assuntos
Artrópodes/efeitos dos fármacos , Níquel/toxicidade , Poluentes do Solo/toxicidade , Solo/química , Animais , Artrópodes/fisiologia , Relação Dose-Resposta a Droga , Dose Letal Mediana , Reprodução/efeitos dos fármacos , Solo/normas , Fatores de Tempo , Testes de Toxicidade
18.
Fish Physiol Biochem ; 45(2): 583-597, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30790148

RESUMO

The aim of this study is to understand fish cold-tolerant mechanism. We analyzed the transcriptional reactions to the cold condition in turbot Scophthalmus maximus by using RNA-seq and microRNA (miRNA)-seq. Meio-gynogenetic diploid turbots were treated at 0 °C to distinguish the cold-tolerant (CT) and cold-sensitive (CS) groups. The results showed that there were quite different responses at both mRNA and miRNA levels, with more up-regulated mRNAs (1069 vs. 194) and less down-regulated miRNAs (4 vs. 1) in CT versus CS relative to the control group. The network of miRNA-transcription factor-mRNA, regulating turbot different response to cold stress, was constructed, which involved in cell cycle, component of cell membrane, signal transduction, and circadian rhythm pathways. The above information demonstrates mechanisms by which cold tolerance is increased in fish.


Assuntos
Adaptação Fisiológica , Temperatura Baixa , Linguados/fisiologia , MicroRNAs/metabolismo , Fatores de Transcrição/metabolismo , Animais , Regulação da Expressão Gênica/fisiologia , MicroRNAs/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fatores de Transcrição/genética
19.
Gene ; 683: 184-194, 2019 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-30315925

RESUMO

Androgens are critical hormones that regulate sex differentiation, sexual maturation, and spermatogenesis in vertebrates, which is mainly mediated by androgen receptors (ARs). Reports on transcript variants of ar (AR encoding gene) in human are almost always associated with cancers and androgen insensitivity syndrome. However, the knowledge of ar variants in teleosts is scarce. In this study, arß and two transcript variants of arα (arα1 and arα2) in olive flounder (Paralichthys olivaceus) were cloned and analyzed. Their expression patterns were investigated in 16 adult female and male tissues by RT-PCR, respectively. arα1 was expressed in the majority of tissues excluding male liver, medulla oblongata and female cerebellum, with higher levels in male gonad, kidney, head kidney, intestine, stomach, spleen, heart and gill than in female. arα2 had similar expression patterns as arα1, with lower levels in general. arß was also widely expressed in various tissues excluding male spleen, female spleen and gill, with higher levels in male gonad, kidney, head kidney, intestine and lower levels in hypothalamus than in female. Compared with arß, much lower expression levels of arα1 and arα2 were detected in different brain areas. The real-time quantitative PCR (qPCR) results showed that the total arα expression level was relatively higher during olive flounder gonadal differentiation and before the onset of testis differentiation, whereas arß was expressed significantly higher during male gonadal differentiation period than female gonadal differentiation period. The in vitro transient transfection assays showed that ARα1, ARα2 and ARß could all suppress the activity of cyp19a (p450arom aromatase gene) promoter, and the inhibitory effect of ARα1 was dose dependent. Our results imply that arα1, arα2 and arß are sex-related genes and they might play important roles in gonadal differentiation in flounder.


Assuntos
Clonagem Molecular/métodos , Linguado/genética , Receptores Androgênicos/genética , Animais , Feminino , Proteínas de Peixes/genética , Regulação da Expressão Gênica , Gônadas/metabolismo , Masculino , Especificidade de Órgãos , Diferenciação Sexual , Distribuição Tecidual
20.
J Sci Food Agric ; 99(6): 3124-3133, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30536731

RESUMO

BACKGROUND: The effects of Ginkgo biloba seed exopleura extract (GSEE) and chitosan (CH) coating on the preservation of ginkgo seeds were investigated. RESULTS: Results showed that CH could alleviate the decay rate, and that CH combined with GSEE (CH-GSEE) treatment further inhibited the development of seed decay due to the additional antifungal activity of GSEE. The nutrient contents, including water, starch and soluble protein, were maintained by both CH-GSEE and CH treatments. CH-GSEE treatment led to better restriction on oxidative stress by decreasing superoxide anion production rate, membrane permeability, malondialdehyde content, respiration rate and ethylene production rate. The antioxidant enzyme activities of peroxidase, superoxide dismutase and catalase in ginkgo seeds were maintained by treatment with CH-GSEE at a higher level. These results were consistent with the enhanced visual appearance, qualities and storability of the CH-GSEE-treated seeds. Principal component analysis provided a global view of the internal relations of the ginkgo seeds with different treatments. CONCLUSIONS: The postharvest qualities of CH-GSEE-treated seeds were better than those of other treatment groups. Therefore, CH-GSEE is an effective and alternative way for inhibiting decay, maintaining quality and extending the postharvest life of ginkgo seeds. © 2018 Society of Chemical Industry.


Assuntos
Quitosana/química , Ginkgo biloba/química , Sementes/química , Ginkgo biloba/metabolismo , Malondialdeído/metabolismo , Peroxidase/metabolismo , Proteínas de Plantas/metabolismo , Controle de Qualidade , Sementes/metabolismo , Superóxido Dismutase/metabolismo , Superóxidos/metabolismo
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