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1.
Med Sci Monit ; 26: e920666, 2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-32253370

RESUMO

BACKGROUND Aging is characterized by progressive deterioration in metabolic and physiological process. The present research assessed the antagonistic effects and mechanisms of Ginsenoside Rg1 (Rg1) on aging of HSCs/HPCs. MATERIAL AND METHODS Fifty male Sprague-Dawley (SD) rats were treated and divided into the following groups: Control (n=10), Model (n=10, treated with D-galactose, as aging model), Rg1 Control (n=10), Rg1 treatment (n=10), and Rg1 prevention (n=10). An aging rat model was established by subcutaneous injection with D-gal. HSC/HPC cells were stained using SA-ß-Gal staining. HSC/HPC cells were examined using flow cytometry assay. CFU-mix assay, with a few modifications, was performed. Cleaved caspase-3, B-cell lymphoma-2 (Bcl-2), and Bcl-2-associated X protein (Bax) were examined using qRT-PCR. Sirtuin 3 (SIRT3) and superoxide dismutase 2 (SOD2) expression was determined using Western blot assay and qRT-PCR. RESULTS Rg1 (treatment and prevention group) significantly decreased SA-ß-Gal-positive staining in Sca-1⁺ HSC/HPC cells compared to that of the D-gal model (p<0.05). Rg1 significantly enhanced formation capacity of CFU-Mix compared to the D-gal model (p<0.05) in Sca-1⁺ HSC/HPC cells. Rg1 significantly reduced G0/G1 phase of Sca-1⁺ HSC/HPC cells compared to that of the D-gal model (p<0.05). Rg1 significantly decreased cleaved caspase 3 and Bax expression, and increased Bcl-2 expression compared to the D-gal model (p<0.05). Rg1 treatment remarkably upregulated expressions of SIRT3 and SOD2 compared to that of the D-gal model group (p<0.05). CONCLUSIONS Rg1 conducted functions of anti-aging in Sca-1⁺ HSC/HPC cells in the D-gal-induced aging model by inhibiting mitochondrial pathway-mediated apoptosis and activating the SIRT3/SOD2 signaling pathway.


Assuntos
Envelhecimento/efeitos dos fármacos , Ginsenosídeos/farmacologia , Envelhecimento/metabolismo , Animais , Apoptose/efeitos dos fármacos , Senescência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Ginsenosídeos/metabolismo , Masculino , Mitocôndrias/efeitos dos fármacos , Oxirredução , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Sirtuínas/metabolismo , Superóxido Dismutase/metabolismo , beta-Galactosidase/metabolismo
2.
J Gen Virol ; 98(3): 506-516, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28005527

RESUMO

Apple fruit crinkle viroid (AFCVd) is a tentative member of the genus Apscaviroid, family Pospiviroidae. AFCVd has a narrow host range and is known to infect apple, hop and persimmon as natural hosts. In this study, tomato, cucumber and wild hop have been identified as new experimental herbaceous hosts. Foliar symptoms were very mild or virtually undetectable, but fruits of infected tomato were small, cracked and distorted. These symptoms resemble those observed on some AFCVd-sensitive apple cultivars. After transfer to tomato, cucumber and wild hop, sequence changes were detected in a natural AFCVd isolate from hop, and major variants in tomato, cucumber and wild hop differed in 10, 8 or 2 nucleotides, respectively, from the predominant one in the inoculum. The major variants in tomato and cucumber were almost identical, and the one in wild hop was very similar to the one in cultivated hop. Detailed analyses of the host-dependent sequence changes that appear in a naturally occurring AFCVd isolate from hop after transfer to tomato using small RNA deep sequence data and infectivity studies with dimeric RNA transcripts followed by progeny analysis indicate that the major AFCVd variant in tomato emerged by selection of a minor variant present in the inoculum (i.e. hop) followed by one to two host-dependent de novo mutations. Comparison of the secondary structures of major variants in hop, tomato and persimmon after transfer to tomato suggested that maintenance of stem-loop structures in the left-hand half of the molecule is critical for infection.


Assuntos
Cucumis sativus/virologia , Doenças das Plantas/virologia , Vírus de Plantas/fisiologia , Solanum lycopersicum/virologia , Viroides/fisiologia , Replicação Viral , Diospyros/virologia , Interações Hospedeiro-Patógeno , Humulus/virologia , Sequências Repetidas Invertidas , Mutação , Conformação de Ácido Nucleico , Vírus de Plantas/genética , Vírus de Plantas/isolamento & purificação , RNA Viral/química , RNA Viral/genética , Viroides/genética , Viroides/isolamento & purificação
3.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(3): 848-52, 2016 Mar.
Artigo em Zh | MEDLINE | ID: mdl-27400536

RESUMO

Interference imaging spectrometer is one of the most important equipments of Chang'E 1 satellite, which is applied to analysis the material composition and its distribution of the surface on the moon. At present, the spectral resolution of level 2B scientific data obtained by existing methods is 325 cm(-1). If we use the description way of wavelength resolution, various spectrum is different: the first band is 7.6 nm, the last band is 29 nm, which introduces two questions: (1) the spectral resolution description way mismatch with the way of ground spectral library used for calibration and comparison; (2) The signal-to-noise ratio of the spectra in the shortwave band is low due to the signal entering narrow band is little. This paper discussed the relationship between wavelength resolution and cut-off function based on the reconstruction model of CE-1 interference imaging spectrometer. It proposed an adjustable cut-off function changing with wavelength or wavelength resolution, while selected the appropriate Sinc function as apodization to realize the reconstruction of arbitrary specified wavelength resolution in the band coverage. Then we used this method to CE-1 on orbit 0B data to get a spectral image of 29 nm wavelength resolution. Finally, by using the signal-to-noise ratio, principal component analysis and unsupervised classification method on the reconstruction results with 2 grade science data from ground application system for comparison, the results showed that: signal-to-noise ratio of the shortwave band increased about 4 times, and the average increased about 2.4 times, the classification based on the spectrum was consistent, and the quality of the data was greatly improved. So, EWSR method has the advantages that: (1) in the case of keeping spectral information steadiness, it can improve the signal-to-noise ratio of shortwave band spectrum though sacrificed part of spectral resolution; (2) it can achieve the spectral data reconstruction which can set arbitrary band position or specify any wavelength resolution within the band range.

4.
Microorganisms ; 9(10)2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34683377

RESUMO

Microbial diversity in an apple orchard cultivated with natural farming practices for over 30 years was compared with conventionally farmed orchards to analyze differences in disease suppression. In this long-term naturally farmed orchard, major apple diseases were more severe than in conventional orchards but milder than in a short-term natural farming orchard. Among major fungal species in the phyllosphere, we found that Aureobasidium pullulans and Cryptococcus victoriae were significantly less abundant in long-term natural farming, while Cladosporium tenuissimum predominated. However, diversity of fungal species in the phyllosphere was not necessarily the main determinant in the disease suppression observed in natural farming; instead, the maintenance of a balanced, constant selection of fungal species under a suitable predominant species such as C. tenuissimum seemed to be the important factors. Analysis of bacteria in the phyllosphere revealed Pseudomonas graminis, a potential inducer of plant defenses, predominated in long-term natural farming in August. Rhizosphere metagenome analysis showed that Cordyceps and Arthrobotrys, fungal genera are known to include insect- or nematode-infecting species, were found only in long-term natural farming. Among soil bacteria, the genus Nitrospira was most abundant, and its level in long-term natural farming was more than double that in the conventionally farmed orchard.

5.
Exp Ther Med ; 20(2): 1245-1252, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32765665

RESUMO

Aging is characterized by a progressive deterioration in metabolic functions. The present study aimed to investigate the antagonistic effects of ginsenoside Rg1 (Rg1) on the γ-ray irradiation-induced aging of mixed hematopoietic stem cells (HSCs) and hematopoietic progenitor cells (HPCs). C57BL/6 mice were divided into a control group, a γ-ray irradiation group that served as an aging mouse model, and an Rg1 group. The Rg1 group was treated with Rg1 at dosage of 20 mg/kg/day for 7 days prior to γ-ray irradiation. The aging mouse model was established by exposing the mice to 6.5-Gy γ-ray total-body irradiation. Stem cell antigen 1 positive (Sca-1+) HSC/HPCs isolated from the mice were examined using a senescence-associated ß-galactosidase (SA-ß-Gal) staining assay. The cell cycle of the HSC/HPCs was examined using flow cytometry. A mixed hematopoietic progenitor cell colony-forming unit (CFU-mix) assay was also conducted. The mRNA and protein expression levels of sirtuin 1 (SIRT1), SIRT3, forkhead box O3 (FOXO3) and superoxide dismutase (SOD2) were evaluated using western blot and reverse transcription-quantitative PCR assays. The results indicated that Rg1 treatment significantly increased white blood cell, red blood cell and platelet counts in peripheral blood compared with those in the γ-ray irradiation group (P<0.05). However, Rg1 significantly attenuated the senescence of Sca-1+ HSC/HPCs in the γ-ray irradiation aging mice model. The proportion of SA-ß-Gal stained HSC/HPCs was significantly decreased and CFU-Mix counts were significantly increased in the Rg1 group compared with the γ-ray irradiation group (P<0.05). Rg1 significantly increased the mRNA and protein levels of SIRT1, SIRT3, FOXO3 and SOD2 in the Sca-1+ HSC/HPCs compared with those in the γ-ray irradiation group (P<0.05). The percentage of Sca-1+ HSC/HPCs arrested at the G1 phase in the Rg1 group was significantly decreased compared with that in the γ-ray irradiation group (P<0.05). In conclusion, the present study indicates that Rg1 exerts anti-aging effects via the regulation of SIRT1-FOXO3 and SIRT3-SOD2 signaling pathways, and triggering the progression of Sca-1+ HSC/HPCs from the G1 phase to the S phase in γ-ray irradiation-induced aging mice.

6.
Guang Pu Xue Yu Guang Pu Fen Xi ; 26(4): 593-6, 2006 Apr.
Artigo em Zh | MEDLINE | ID: mdl-16836116

RESUMO

A new method and technology for measuring time-dependent spectra excited by pulse laser was reported in the present paper, in which a multi-fiber delayer combined with a two dimensional CCD array detector was employed for collecting and processing the spectra. The multi-fiber delayer consists of five fibers with a length difference of 1-2 m (relative delay time 5-10 ns), and the optical multi channel analyzer is PARC OMA-4. The time-dependent spectra, i. e. the spectra of R6G dye laser, the SRS spectra of acetone, and the plasma emission spectra of metal Mo excited by a double frequency YAG pulse laser with a time resolution of 5 ns were obtained.

7.
Guang Pu Xue Yu Guang Pu Fen Xi ; 25(5): 648-50, 2005 May.
Artigo em Zh | MEDLINE | ID: mdl-16128053

RESUMO

It is reported that the Rhodamine 6G fluorescence in water solution changes with different concentration SDS excited by a 532 nm laser. A small amount of SDS in Rhodamine 6G water solution will reduce the intensity of fluorescence. More SDS enhances R6G fluorescence. The enhancement ratio can reach up to 3.1 when SDS concentration is 6 x 10(-2) mol L(-1) in 5 x 10(-5) mol L(-1) R6G water solution. Dye laser threshold decreases when SDS concentration is 2 x 10(-2) mol x L(-1) in 1 x 10(-4) mol x L(-1) R6G water solution. The physical mechanism of the phenomena is analyzed by the absorption spectra of different concentration R6G water solutions and the fluorescence spectra of R6G water solutions adulterated with different concentration SDS.


Assuntos
Fluorescência , Lasers , Rodaminas/química , Dodecilsulfato de Sódio/química , Água/química , Soluções , Espectrometria de Fluorescência/instrumentação , Espectrometria de Fluorescência/métodos
8.
Sci Rep ; 5: 17949, 2015 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-26656294

RESUMO

Previous attempts to develop RNAi-mediated viroid-resistant transgenic plants using nearly full-length Potato spindle tuber viroid (PSTVd) hairpin RNA (hpRNA) were successful; however unusual phenotypes resembling viroid infection occurred. Therefore, in the present work, transgenic Nicotiana benthamiana lines expressing both partial and truncated versions of PSTVd hpRNA were developed. Specifically, seven partial or truncated versions of PSTVd sequences were selected according to the hotspots of both PSTVd-sRNAs and functional domains of the PSTVd. A total of 21 transgenic lines Nicotiana benthamiana were developed under the control of either the CaMV-35S or the CoYMV promoters. All of the transgenic lines established here were monitored for the induction of phenotypic changes, for PSTVd-sRNA expression and for the resistance against PSTVd infection. Additionally, this study demonstrates the use of inverted repeat construct sequences as short as 26- to -49 nucleotides for both the efficient expression of the PSTVd-sRNA and the inhibition of PSTVd infection.


Assuntos
Doenças das Plantas/genética , Doenças das Plantas/virologia , Vírus de Plantas/fisiologia , Interferência de RNA , RNA Interferente Pequeno/genética , RNA Viral/genética , Viroides/fisiologia , Sequência de Bases , Sítios de Ligação , Resistência à Doença/genética , Expressão Gênica , Sequências Repetidas Invertidas , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Plantas Geneticamente Modificadas/genética , Regiões Promotoras Genéticas , RNA Interferente Pequeno/química , RNA Viral/química
9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 24(4): 396-8, 2004 Apr.
Artigo em Zh | MEDLINE | ID: mdl-15766139

RESUMO

The incident pulse intensity wave will cause the induced fluorescence wave, which will lead to the obvious error of experiment results. A double-light-beam correlation method between the incident laser and the fluorescence was used to decrease such error efficiently in the experiments. A good correlation factor over 0.9 was obtained by the method in the experiment of R6G fluorescence enhanced by SDS. The method is better than sampling-averaging method when the incident laser intensity has more waves.


Assuntos
Fluorescência , Lasers , Espectrometria de Fluorescência/métodos , Luz , Dispositivos Ópticos , Espalhamento de Radiação
10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 24(12): 1499-501, 2004 Dec.
Artigo em Zh | MEDLINE | ID: mdl-15828310

RESUMO

In this paper, the authors reported a new method for measuring transient time-dependent spectra using multi-fiber delay coupler and optical multi-channel analysis technique. The fiber delay coupler consists of five fibers with different lengths and its time-delay between two fibers is determined by the different fiber lengths. The light beams that came from the fiber coupler were coupled by a lens system into the slit of a spectrograph and formed a spectral pattern on the focus plane of the spectrometer. A two-dimensional CCD detector converted the optical pattern into an electrical pattern, and then the transient time-dependent spectra were obtained by a personal computer. The experimental setup was constructed, and the transient time-dependent spectra were measured for KCl crystal shocked by a high speed pill. The time resolution was 20 ns, and the spectral intensity resolution reached 1/18 bit.


Assuntos
Cristalinas/química , Desenho de Equipamento/métodos , Tecnologia de Fibra Óptica/métodos , Cloreto de Potássio/química , Fibras Ópticas , Análise Espectral , Fatores de Tempo
11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 24(5): 634-6, 2004 May.
Artigo em Zh | MEDLINE | ID: mdl-15769068

RESUMO

A new kind of instrument and method for simultaneous and real-time collection of multi-object spectra by using multi-fiber coupling and Optical Multi-channel Analysis (OMA) was reported. The spectral signals of one object, three objects and five objects were collected successfully in experiments. The spatial resolution of 0.5 mm and detected spectral range of 200-1100 nm were reached, and at most twenty objects could be collected on the image plane of 1 cm2 area with OMA 4 system. The design of the coupling lens's light path was discussed to guarantee enough light energy to enter the instrument and little effect on the resolution of spectral instrument. The instrument can be applied widely to the areas of supervising and controlling the quality of light beam in transmission and in the time-resolved and spatial-resolved spectral measurement.


Assuntos
Desenho de Equipamento/instrumentação , Tecnologia de Fibra Óptica/instrumentação , Espalhamento de Radiação , Processamento de Sinais Assistido por Computador/instrumentação , Algoritmos , Luz , Fibras Ópticas/tendências , Refratometria/instrumentação , Projetos de Pesquisa/tendências , Software
12.
PLoS One ; 7(3): e34249, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22479577

RESUMO

BACKGROUND: To monitor the richness in microbial inhabitants in the phyllosphere of apple trees cultivated under various cultural and environmental conditions, we developed an oligo-DNA macroarray for major pathogenic and non-pathogenic fungi and bacteria inhabiting the phyllosphere of apple trees. METHODS AND FINDINGS: First, we isolated culturable fungi and bacteria from apple orchards by an agar-plate culture method, and detected 32 fungal and 34 bacterial species. Alternaria, Aureobasidium, Cladosporium, Rhodotorula, Cystofilobasidium, and Epicoccum genera were predominant among the fungi, and Bacillus, Pseudomonas, Sphingomonas, Methylobacterium, and Pantoea genera were predominant among the bacteria. Based on the data, we selected 29 major non-pathogenic and 12 phytopathogenic fungi and bacteria as the targets of macroarray. Forty-one species-specific 40-base pair long oligo-DNA sequences were selected from the nucleotide sequences of rDNA-internal transcribed spacer region for fungi and 16S rDNA for bacteria. The oligo-DNAs were fixed on nylon membrane and hybridized with digoxigenin-labeled cRNA probes prepared for each species. All arrays except those for Alternaria, Bacillus, and their related species, were specifically hybridized. The array was sensitive enough to detect 10(3) CFU for Aureobasidium pullulans and Bacillus cereus. Nucleotide sequencing of 100 each of independent fungal rDNA-ITS and bacterial 16S-rDNA sequences from apple tree was in agreement with the macroarray data obtained using the same sample. Finally, we analyzed the richness in the microbial inhabitants in the samples collected from apple trees in four orchards. Major apple pathogens that cause scab, Alternaria blotch, and Marssonina blotch were detected along with several non-phytopathogenic fungal and bacterial inhabitants. CONCLUSIONS: The macroarray technique presented here is a strong tool to monitor the major microbial species and the community structures in the phyllosphere of apple trees and identify key species antagonistic, supportive or co-operative to specific pathogens in the orchard managed under different environmental conditions.


Assuntos
Bactérias/genética , Fungos/genética , Malus/microbiologia , Oligonucleotídeos/genética , DNA Ribossômico/genética , Meio Ambiente , Regulação da Expressão Gênica , Hibridização de Ácido Nucleico , Análise de Sequência com Séries de Oligonucleotídeos , Doenças das Plantas/microbiologia , Reprodutibilidade dos Testes , Estações do Ano , Análise de Sequência de DNA , Especificidade da Espécie , Árvores/microbiologia
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