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1.
Front Plant Sci ; 7: 931, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27458463

RESUMO

Saline-alkaline stress, caused by high levels of harmful carbonate salts and high soil pH, is a major abiotic stress that affects crop productivity. Alfalfa is a widely cultivated perennial forage legume with some tolerance to biotic and abiotic stresses, especially to saline-alkaline stress. To elucidate the mechanism underlying plant saline-alkaline tolerance, we conducted transcriptome analysis of whole alfalfa seedlings treated with saline-alkaline solutions for 0 day (control), 1 day (short-term treatment), and 7 days (long-term treatment) using ion torrent sequencing technology. A transcriptome database dataset of 53,853 unigenes was generated, and 2,286 and 2,233 genes were differentially expressed in the short-term and long-term treatment, respectively. Gene ontology analysis revealed 14 highly enriched pathways and demonstrated the differential response of metabolic pathways between the short-term and long-term treatment. The expression levels of 109 and 96 transcription factors were significantly altered significantly after 1 day and 7 days of treatment, respectively. Specific responses of peroxidase, flavonoids, and the light pathway component indicated that the antioxidant capacity was one of the central mechanisms of saline-alkaline stress tolerance response in alfalfa. Among the 18 differentially expressed genes examined by real time PCR, the expression levels of eight genes, including inositol transporter, DNA binding protein, raffinose synthase, ferritin, aldo/keto reductase, glutathione S-transferase, xyloglucan endotrans glucosylase, and a NAC transcription factor, exhibited different patterns in response to saline and alkaline stress. The expression levels of the NAC transcription factor and glutathione S-transferase were altered significantly under saline stress and saline-alkaline stress; they were upregulated under saline-alkaline stress and downregulated under salt stress. Physiology assays showed an increased concentration of reactive oxygen species and malondialdehyde and a decreased content of chlorophyll, indicating that anti-oxidation and detoxification play an important role in response to saline-alkaline stress. Overall, the transcriptome analysis provided novel insights into the saline-alkaline stress tolerance response mechanisms in alfalfa.

2.
Bioorg Med Chem Lett ; 22(22): 6882-7, 2012 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-23044370

RESUMO

A series of novel pyrazole peptidomimetics was synthesized from 3-aryl-1-arylmethyl-1H-pyrazole-5-carboxylic acid and amino acid ester. Structures of the compounds were characterized by means of IR, (1)H NMR and mass spectroscopy. Compounds 5e and 5k suppress effectively the growth of A549 lung cancer cells. Preliminary research on the mechanism of action showed that the inhibition might perform through combination of apoptosis, autophagy and cell cycle arrest.


Assuntos
Antineoplásicos/síntese química , Pirazóis/química , Pirazóis/síntese química , Serina/análogos & derivados , Antineoplásicos/química , Antineoplásicos/toxicidade , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Ácidos Carboxílicos/química , Linhagem Celular Tumoral , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Humanos , Peptidomiméticos , Pirazóis/toxicidade , Serina/síntese química , Serina/química , Serina/toxicidade , Relação Estrutura-Atividade
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 81(1): 372-9, 2011 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-21733750

RESUMO

A series of fluorescent compounds, containing pyrazolo[1,5-a]pyrazin-4(5H)-one moiety, were designed and synthesized from ethyl 1-(2-oxo-2-phenylethyl)-3-phenyl-1H-pyrazole-5-carboxylates. The structures of the compounds have been confirmed by IR, (1)H NMR, HRMS and X-ray crystal diffraction. The optical properties of the compounds were investigated by UV-vis absorption and fluorescence spectroscopy. The effect of pH on the UV-vis absorption of compound 2a in methanol-H(2)O solutions was studied and interpreted by theory calculation. The pK(a) value of compound 2a was determined by the absorption spectra.


Assuntos
Pirazinas/química , Pirazóis/química , Piridinas/química , Piridinas/síntese química , Cristalografia por Raios X , Modelos Biológicos , Modelos Moleculares , Simulação de Dinâmica Molecular , Estrutura Molecular , Pirazinas/síntese química , Pirazóis/síntese química , Espectrometria de Fluorescência/métodos
4.
Bioorg Med Chem Lett ; 20(16): 4766-70, 2010 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-20637610

RESUMO

A series of novel oxime-containing pyrazole derivatives were synthesized by the reaction of ethyl 3-phenyl-1H-pyrazole-5-carboxylate derivatives and 2-bromo-1-phenylethanone followed by the reaction with hydroxylamine hydrochloride. The structures were determined by IR, (1)H NMR, HRMS, and X-ray analysis. A dose- and time-dependent inhibition of proliferation was observed in A549 lung cancer cell after compound treatment. Inhibition of growth was mainly attributed to the autophagy induction.


Assuntos
Antineoplásicos/síntese química , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Neoplasias Pulmonares/tratamento farmacológico , Oximas/química , Pirazóis/química , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Cristalografia por Raios X , Avaliação Pré-Clínica de Medicamentos , Humanos , Neoplasias Pulmonares/patologia , Conformação Molecular , Pirazóis/síntese química , Pirazóis/uso terapêutico , Relação Estrutura-Atividade
5.
J Neurotrauma ; 26(11): 1999-2013, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19604101

RESUMO

Traumatic brain injury (TBI) has a high incidence of long-term morbidity. Manganese-enhanced MRI (MEMRI) provides high contrast structural and functional detail of the brain in-vivo. The study utilized serial MEMRI scanning in the fluid percussion injury (FPI) rat's model to assess long-term changes in the brain following TBI. Rats underwent a left-sided craniotomy and a 3.5 atmosphere FPI pulse (n = 23) or sham procedure (n = 22). MEMRI acquisition was performed at baseline, 1 day, 1 month, and 6 months after FPI. Volume changes and MnCl(2) enhancement were measured blindly using region-of-interest analysis and the results analyzed with repeated measures MANOVA. Compared to the shams, FPI animals showed a progressive decrease in brain volume from 1 (right, p = 0.02; left, p = 0.008) to 6 months (right, p = 0.04; left, p = 0.006), with progression over time (F = 7.16, p = 0.00018). Similar changes were found in the cortex and the hippocampus. Conversely, the ventricular volume was increased at 1 (p = 0.02) and 6 months (p = 0.003), with progression over time (F = 7.27, p = 0.0001). There were no differences in thalamic or amygdalae volumes. The severity of the early neuromotor deficits and the T2 signal intensity of the subacute focal lesion were highly predictive of the severity of the long-term hippocampal decrease, and the former was also associated with the degree of neuronal sprouting. Differential MnCl(2) enhancement occurred only in the dentate gyrus at 1 month on the side of trauma (p = 0.04). Progressive functional and structural changes occur in specific brain regions post-FPI. The severity of the neuromotor deficit and focal signal changes on MRI subacutely post-injury are predictive of severity of these long-term neurodegenerative changes.


Assuntos
Lesões Encefálicas/patologia , Aumento da Imagem/métodos , Imageamento por Ressonância Magnética/métodos , Manganês , Animais , Eletroencefalografia , Processamento de Imagem Assistida por Computador , Masculino , Ratos , Ratos Wistar
6.
J Magn Reson Imaging ; 29(5): 1027-34, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19388129

RESUMO

PURPOSE: To report the detection of structural and functional biological changes in living animals using small animal in vivo MRI that complements traditional ex vivo histological techniques. We report the development and validation of the application of large deformation high dimensional mapping (HDM-LD) segmentation for the hippocampus in the rat. MATERIALS AND METHODS: High resolution volumetric T2 weighted MRI images were acquired at 4.7 Tesla from six male in-breed nonepileptic Wistar rats. Two HDM-LD segmentations of the hippocampus (automated 1 and automated 2) were compared with the manual segmentations of two investigators who independently segmented the hippocampi (manual 1 and manual 2). RESULTS: The mean overlap for the hippocampi between automated 1 and automated 2 for the right hippocampi was 94.4% (SD 1.0) and for the left hippocampi was 94.3% (SD 2.5), while the mean overlap between automated 1 and manual 1 for the right hippocampi was 91.4% (SD 1.3) and for the left hippocampi was 91.9% (SD 1.4). Mean values for absolute differences for comparisons of all the segmentations were the following: automated 1 versus automated 2, 3.2% (SD 1.0); manual 1 versus manual 2 6.82% (SD 5.22); automated 1 versus manual 1 13.0% (SD 1.8). CONCLUSION: HDM-LD can be applied to obtain accurate and reproducible three-dimensional segmentations of the hippocampus from rat MR images. HDM-LD will be a useful tool for investigations of hippocampal structural changes in vivo in rat models of human disease.


Assuntos
Envelhecimento/patologia , Algoritmos , Hipocampo/anatomia & histologia , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Animais , Masculino , Ratos , Ratos Wistar , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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