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1.
Artigo em Inglês | MEDLINE | ID: mdl-31561447

RESUMO

The widespread use of fluazifop-p-butyl (FPB) contributes to its presence in the environment. Considering the ecological risks of FPB residues in the environment, the anatase nanometer titanium dioxide (nano-TiO2) mediated photocatalytic degradation of FPB was studied by smearing FPB and nano-TiO2 together on a glass plane; illumination, trimethylsilane derivatization of photolysis products, high performance liquid chromatography (HPLC) quantitative analysis and gas chromatograph-mass spectrometer (GC-MS) identification were used. Results showed that the first order dynamic model could describe the photodegradation of FPB by nano-TiO2 mediated, and the photodegradation and photosensitization rates were found to be positively correlated with the dose of nano-TiO2 at lower dose ranges. It is noticeable that a strong photosensitization effect was exhibited on degradation of FPB, not only under high-pressure mercury lamps, but also simulated sunlight (xenon lamp light). Ultimately, twelve main photolytic products were reasonably speculated, whilst five photolysis pathways were proposed. These results together suggest that nano-TiO2 can be used as an effective photosensitizer to accelerate FPB photolysis.

2.
BMC Plant Biol ; 19(1): 298, 2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31286900

RESUMO

BACKGROUND: Homeodomain-leucine zipper (HD-ZIP) transcription factors play important roles in the growth, development and stress responses of plants, including (presumably) physic nut (Jatropha curcas), which has high drought and salinity tolerance. However, although physic nut's genome has been released, there is little knowledge of the functions, expression profiles and evolutionary histories of the species' HD-ZIP genes. RESULTS: In this study, 32 HD-ZIP genes were identified in the physic nut genome (JcHDZs) and divided into four groups (I-IV) based on phylogenetic analysis with homologs from rice, maize and Arabidopsis. The analysis also showed that most of the JcHDZ genes were closer to members from Arabidopsis than to members from rice and maize. Of the 32 JcHDZ genes, most showed differential expression patterns among four tissues (root, stem cortex, leaf, and seed). Expression profile analysis based on RNA-seq data indicated that 15 of the JcHDZ genes respond to at least one abiotic stressor (drought and/or salinity) in leaves at least at one time point. Transient expression of a JcHDZ16-YFP fusion protein in Arabidopsis protoplasts cells showed that JcHDZ16 is localized in the nucleus. In addition, rice seedlings transgenically expressing JcHDZ16 had lower proline contents and activities of antioxidant enzymes (catalase and superoxide dismutase) together with higher relative electrolyte leakage and malondialdehyde contents under salt stress conditions (indicating higher sensitivity) than wild-type plants. The transgenic seedlings also showed increased sensitivity to exogenous ABA, and increases in the transcriptional abundance of several salt stress-responsive genes were impaired in their responses to salt stress. Further data on JcHDZ16-overexpressing plants subjected to salt stress treatment verified the putative role of JcHDZ genes in salt stress responses. CONCLUSION: Our results may provide foundations for further investigation of functions of JcHDZ genes in responses to abiotic stress, and promote application of JcHDZ genes in physic nut breeding.


Assuntos
Jatropha/genética , Oryza/genética , Proteínas de Plantas/genética , Fatores de Transcrição/genética , Estudo de Associação Genômica Ampla , Jatropha/metabolismo , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Fatores de Transcrição/metabolismo , Transcriptoma
3.
Neuropeptides ; 51: 43-54, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25911494

RESUMO

The contribution of the cerebrospinal fluid-contacting nucleus (CSF-contacting nucleus) and adrenomedullin (ADM) to the developmental modulation of stressful events remains controversial. This study explored the effects of endogenous ADM in the CSF-contacting nucleus on immobilization of stress-induced physiological parameter disorders and glucocorticoid hormone releasing hormone (CRH), rat plasma corticosterone expression, and verification of such effects by artificially lowering ADM expression in the CSF-contacting nucleus by targeted ablation of the nucleus. Immunohistochemical experiments showed that ADM-like immunoreactivity and the calcitonin receptor-like receptor (CRLR) marker were localized in the CSF-contacting nucleus. After 7 continuous days of chronic immobilization stress (CIS), animals exhibited anxiety-like behavior. Also, an increase in serum corticosterone, and enhanced expression of ADM in the CSF-contacting nucleus were observed, following activation by CIS. The intracerebroventricular (i.c.v.) administration of the ADM receptor antagonist AM22-52 significantly reduced ADM in the CSF-contacting nucleus, additionally, blocked the effects of ADM, meaning the expression of CRH in the hypothalamic paraventricular nucleus (Pa) and serum corticosterone level were increased, and the physiological parameters of the rats became correspondingly deteriorated. Additionally, the i.c.v. administration of cholera toxin subunit B-saporin (CB-SAP), a cytotoxin coupled to a cholera toxin subunit, completely eliminated the CSF-contacting nucleus, worsening the reaction of the body to CIS. The collective results demonstrated that ADM acted as a stress-related peptide in the CSF-contacting nucleus, and its lower expression and blocked effects in the nucleus contributed to the deterioration of stress-induced physiologic parameter disorders as well as the excessive expressions of stress-related hormones which were part of the hypothalamic-pituitary-adrenal (HPA) axis.


Assuntos
Adrenomedulina/metabolismo , Sistema Hipotálamo-Hipofisário/metabolismo , Núcleo Hipotalâmico Paraventricular/metabolismo , Estresse Fisiológico/fisiologia , Adrenomedulina/farmacologia , Animais , Proteína Semelhante a Receptor de Calcitonina/metabolismo , Corticosterona/sangue , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Masculino , Núcleo Hipotalâmico Paraventricular/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores de Adrenomedulina/antagonistas & inibidores , Restrição Física , Estresse Fisiológico/efeitos dos fármacos
4.
Neurochem Res ; 40(5): 1053-62, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25846007

RESUMO

The cerebrospinal fluid-contacting nucleus (CSF-CN) has been demonstrated to be involved in neuropathic pain, but the underlying molecular mechanisms remain unclear. Previous work has shown that mTOR and ERK1/2 are important signaling pathways regulating neuropathic pain. However, studies on the interactions between these major pathways in neuropathic pain are very rare. Therefore, the purpose of this study is to determine whether mTOR and ERK1/2 exist in the CSF-CN and elucidate their alterations in neuropathic pain, especially, the crosstalk between them. Our results showed that mTOR and ERK1/2 were distributed in the CSF-CN, and their expression levels were increased in chronic constriction injury (CCI)-induced neuropathic pain. Furthermore, the injection of both the mTOR antagonist rapamycin and the ERK1/2 antagonist U0126 into the lateral ventricle of the brain attenuated CCI-induced neuropathic pain. Inhibition of the ERK1/2 pathway had little impact on mTOR signaling, but inhibition of the mTOR pathway significantly increased ERK/2 signaling. The coadministration of rapamycin and U0126 inhibited the rapamycin-induced upregulation of ERK, and had a greater effect on pain behaviors than did the single-drug administrations. These data extend our understanding of the relationship between mTOR and ERK in the supraspinal site and demonstrate that the CSF-CN participates in neuropathic pain via the regulation of mTOR and ERK1/2.


Assuntos
Núcleo Celular/metabolismo , Líquido Cefalorraquidiano/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Neuralgia/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Animais , Núcleo Celular/química , Núcleo Celular/efeitos dos fármacos , Líquido Cefalorraquidiano/química , Líquido Cefalorraquidiano/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Medição da Dor/métodos , Ratos , Ratos Sprague-Dawley , Sirolimo/farmacologia , Serina-Treonina Quinases TOR/análise , Serina-Treonina Quinases TOR/antagonistas & inibidores
5.
Physiol Behav ; 147: 291-9, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-25911266

RESUMO

The brainstem plays an important role in controlling sodium and water homeostasis. It is a major regulatory site for autonomic and motor functions. Moreover, it integrates cerebrospinal fluid (CSF) signals with neuronal and hormonal signals. Evidence suggests that the CSF-contacting nucleus (CSF-CN) transmits and integrates CSF signals, but, the definitive role of CSF-CN in sodium homeostasis is poorly understood. In this study, we used c-Fos as a marker of neuronal activity and causing colocalization of Nax channel and 5-HT. This proved that CSF-CN played a role in sensing the increase of CSF sodium level. Then, we determined the role of the CSF-contacting nucleus in increasing the sodium appetite of rats. So, we performed targeted lesion of the CSF-contacting nucleus in the brainstem using the cholera toxin subunit B-saporin (CB-SAP), a cytotoxin coupled to cholera toxin subunit B. The lesion of the CSF-CN showed decreased and degenerative neurons, while sodium appetite have increased and Fos immunocytochemistry detected neuronal activity in the lateral parabrachial nucleus (LPBN), but not in the subfornical organ (SFO) and organum vasculosum of the lamina terminalis (OVLT). These results indicate that the CSF-CN plays an important role in sensing CSF sodium level and satiating sodium appetite by influencing the LPBN but not SFO and OVLT. The Nax channel and 5-HT might be the molecular mechanisms through which contribute to sodium homeostasis.


Assuntos
Apetite/fisiologia , Tronco Encefálico/metabolismo , Líquido Cefalorraquidiano , Neurônios/fisiologia , Sódio na Dieta/administração & dosagem , Órgão Subfornical/fisiologia , Animais , Apetite/efeitos dos fármacos , Tronco Encefálico/citologia , Tronco Encefálico/efeitos dos fármacos , Toxina da Cólera/farmacocinética , Ingestão de Líquidos , Furosemida/farmacologia , Peroxidase do Rábano Silvestre/metabolismo , Injeções Intraventriculares , Masculino , Neurônios/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-fos/metabolismo , Ratos , Ratos Sprague-Dawley , Proteínas Inativadoras de Ribossomos Tipo 1/farmacocinética , Solução Salina Hipertônica/farmacologia , Saporinas , Serotonina/metabolismo , Inibidores de Simportadores de Cloreto de Sódio e Potássio/farmacologia , Órgão Subfornical/citologia , Canais de Sódio Disparados por Voltagem/metabolismo
6.
J Food Sci ; 77(4): T63-9, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22515255

RESUMO

This paper presents the generation of monoclonal antibodies (mAbs) with high specificity against 19-nortestosterone (NT) through cell fusion procedures, and the development of mAb-based heterologous direct competitive enzyme-linked immunoabsorbent assay (dcELISA) methods to detect NT residue using one of these hybridomas (clone 3B8-E6). Under optimal experimental conditions, this assay exhibited a working range of 0.004 to 19 ng/mL with IC50 and limit of detection values of 0.28 and 0.002 ng/mL, respectively, when it was run in 0.01M phosphate-buffered saline (pH 7.4). Except for minor cross-reactivity with ß-boldenone (6.9%) and trenbolone (1.2%), other interference to the assay was negligible (<0.05%). No significant differences (P > 0.05) were found for IC50 values when the pH of the assay buffer ranged from 6 to 8 and phosphate ion concentration was less than 20 mM. The dcELISA can tolerate higher concentrations of methanol than other organic solvents tested. When applied to bovine sample, the correlation coefficients (R) of the dcELISA and GC-MS data were 0.9918 in muscle, 0.9834 in liver, and 0.9976 in kidney. Therefore, this assay has the potential to be incorporated into a quantitative monitoring program for the rapid screening of NT residue in food.


Assuntos
Anabolizantes/análise , Resíduos de Drogas/análise , Contaminação de Alimentos , Inspeção de Alimentos/métodos , Carne/análise , Nandrolona/análise , Animais , Anticorpos Monoclonais/análise , Especificidade de Anticorpos , Ligação Competitiva , Bovinos , Reações Cruzadas , Ensaio de Imunoadsorção Enzimática , Concentração de Íons de Hidrogênio , Rim/química , Limite de Detecção , Fígado/química , Músculo Esquelético/química , Testosterona/análogos & derivados , Testosterona/análise , Acetato de Trembolona/análise
7.
J Zhejiang Univ Sci B ; 12(6): 460-7, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21634039

RESUMO

A rapid sample treatment procedure for the gas chromatography-tandem mass spectrometry (GC-MS) determination of 19-nortestosterone (19-NT) in animal tissues has been developed. In our optimized procedures, enzymatic hydrolysis with ß-glucuronidase from Escherichia coli was performed in an acetate buffer (pH 5.2, 0.2 mol/L). Next, the homogenate was mixed with methanol and heated at 60 °C for 15 min, then placed in an ice-bath at -18 °C for 2 h. After liquid-liquid extraction with n-hexane, the analytes were subjected to a normal-phase solid phase extraction (SPE) C18 cartridge for clean-up. The dried organic extracts were derivatized with heptafluorobutyric anhydride (HFBA), and then the products were injected into GC-MS. Using electron impact mass spectrometry (EI-MS) with positive chemical ionization (PCI), four diagnostic ions (m/z 666, 453, 318, and 306) were determined. A standard calibration curve over the concentration range of 1-20 ng/g was reached, with Y=467084X-68354 (R²=0.9997) for 19-NT, and the detection limit was 0.3 ng. When applied to spiked samples collected from bovine and ovine, the recoveries ranged from 63% to 101% with relative standard deviation (RSD) between 2.7% and 8.9%. The procedure is a highly efficient, sensitive, and more economical method which offers considerable potential to resolve cases of suspected nandrolone doping in husbandry animals.


Assuntos
Resíduos de Drogas/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Carne/análise , Nandrolona/análise , Espectrometria de Massas em Tandem/métodos , Animais , Bovinos , Nandrolona/isolamento & purificação , Ovinos , Extração em Fase Sólida
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