Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 83
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Small ; 20(24): e2309482, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38150668

RESUMO

Developing intelligently targeted drugs with low side effects is urgent for cancer treatment. Toward this goal, a tumor-specific cascade-activating smart prodrug system consisting of a G-quadruplex(G4)-modulated tumor-targeted DNA vehicle and a well-designed cellular stimuli-responsive ligand-drug conjugates (LDCs) is proposed. An original "donor-acceptor" binary fluorescent ligand, with ultrahigh affinity, brightness, and photostability, is engineered to tightly bind G4 structures and significantly improve the nuclease resistance of the DNA vehicle, which serves as a bridge contributing to the construction of the prodrug system, named ApG4/LDCs. Sodium nitroprusside and doxorubicin are loaded into ApG4/LDCs in one pot and generate nitric oxide and superoxide anion in response to cancer cellular environments, which in cascade generates peroxynitrite to cause DNA damage while promoting the self-monitored drug release to achieve enhanced targeted therapy. Such a cascade activation and self-reinforcement process is executed only when the prodrug system targets the tumor tissue followed by cell uptake, showing significant antitumor efficacy and greatly weakening the damage to normal tissues. Given the unique features, the innovative strategy for prodrug design may open a new door to precision disease treatment.


Assuntos
Doxorrubicina , Pró-Fármacos , Pró-Fármacos/química , Pró-Fármacos/farmacologia , Pró-Fármacos/uso terapêutico , Humanos , Doxorrubicina/farmacologia , Doxorrubicina/química , Animais , Linhagem Celular Tumoral , Neoplasias/tratamento farmacológico , Quadruplex G , Ligantes
2.
Angew Chem Int Ed Engl ; 63(16): e202319982, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38361437

RESUMO

Enzymes are considered safe and effective therapeutic tools for various diseases. With the increasing integration of biomedicine and nanotechnology, artificial nanozymes offer advanced controllability and functionality in medical design. However, several notable gaps, such as catalytic diversity, specificity and biosafety, still exist between nanozymes and their native counterparts. Here we report a non-metal single-selenium (Se)-atom nanozyme (SeSAE), which exhibits potent nicotinamide adenine dinucleotide phosphate (NADPH) oxidase-mimetic activity. This novel single atom nanozyme provides a safe alternative to conventional metal-based catalysts and effectively cuts off the cellular energy and reduction equivalents through its distinctive catalytic function in tumors. In this study, we have demonstrated the substantial efficacy of SeSAE as an antitumor nanomedicine across diverse mouse models without discernible systemic adverse effects. The mechanism of the NADPH oxidase-like activity of the non-metal SeSAE was rationalized by density functional theory calculations. Furthermore, comprehensive elucidation of the biological functions, cell death pathways, and metabolic remodeling effects of the nanozyme was conducted, aiming to provide valuable insights into the development of single atom nanozymes with clinical translation potential.


Assuntos
Nanotecnologia , Neoplasias , Animais , Camundongos , Metais , Catálise , Neoplasias/tratamento farmacológico , Nanomedicina
3.
Opt Express ; 31(2): 1878-1887, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36785213

RESUMO

A high temporal waveform fidelity stimulated Brillouin scattering phase conjugate mirror (SBS-PCM) with high energy efficiency, based on a novel medium, Novec-7500, is proposed and practically achieved in this study. A theoretical analysis reveals that the temporal-domain waveform distortion is caused by the inherent pulse duration compression effect of the SBS, and this undesirable phenomenon can be significantly suppressed by decreasing the compression coefficient (CC afterwards), which is defined as the gain coefficient divided by the phonon lifetime, which coefficient and is identified as the key parameter for high waveform-fidelity in SBS-PCM. The feasibility of this approach was demonstrated experimentally, in which a reflected pulse with waveform symmetry equals to the pump and an average pulse duration of 0.974 τp (τp is the duration of pump) with an energy efficiency of over 90% was achieved using Novec-7500.

4.
Opt Express ; 31(2): 2942-2955, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36785296

RESUMO

Free-space Brillouin lasers (BLs) are capable of generating high-power, narrow-linewidth laser outputs at specific wavelengths. Although there have been impressive experimental demonstrations of these lasers, there is an absence of a corresponding theory that describes the dynamic processes that occur within them. This paper presents a time-independent analytical model that describes the generation of the first-order Stokes field within free-space BLs. This model is based on the cavity resonance enhancement theory and coupled wave equations that govern the processes of stimulated Brillouin scattering (SBS). This model is validated using an experimental diamond BL to numerically simulate the influence of the cavity design parameters on the SBS threshold, pump enhancement characteristics, and power of the generated Stokes field. Specifically, the model is used to determine the SBS cavity coupler reflectance to yield the maximum Stokes field output power and efficiency, which is also a function of the pump power and other cavity design parameters. This analysis shows that the appropriate choice of Brillouin cavity coupler reflectance maximizes the Stokes field output power for a given pump power. Furthermore, the onset of higher-order Stokes fields that are undesirable in the context of single-frequency laser operation were inhibited. This study aids in understanding the relationship between the cavity parameters and resultant laser characteristics for the design and optimization of laser systems.

5.
J Fish Dis ; 46(2): 99-112, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36263741

RESUMO

The Streptomyces lateritius Z1-26 was isolated from soil samples which showed broad-spectrum antibacterial activity against a broad range of fish pathogens. The In Vivo Imaging System (IVIS) monitored that strain Z1-26 could survive and colonize in the gills and abdomen of crucian carp. The effects of dietary supplementation with strain Z1-26 were evaluated with respect to the growth performance, antioxidant capacity, and immune response of crucian carp. The results showed that the Z1-26-fed fish had a significantly higher growth rate than the fish fed the control diet. The immune and antioxidant parameters revealed that the non-specific immune indicators (AKP, SOD, and LZM) of the serum, the expression of immune-related genes (IgM, C3, and LZM), and antioxidant-related genes (Nrf2 and Keap1) of the immune organs were significantly increased, whereas the expression of pro-inflammatory factors (IL-1ß, IL-8, and TNF-α) of the immune organs was significantly down-regulated in crucian carp fed strain Z1-26 compared with fish fed a control diet. Moreover, fish fed with Z1-26 supplemented diets showed a significantly improved survival rate after Aeromonas hydrophila infection. In addition, the whole genome analysis showed that strain Z1-26 possesses 28 gene clusters, including 6 polyketide synthetase (PKS), 4 non-ribosomal peptide-synthetase (NRPS), 1 bacteriocin, and 1 lantipeptide. In summary, these results indicated that strain Z1-26 could improve the growth performance and disease resistance in crucian carp, and has the potential to be developed as a candidate probiotics for the control of bacterial diseases in aquaculture.


Assuntos
Carpas , Doenças dos Peixes , Infecções por Bactérias Gram-Negativas , Animais , Carpa Dourada/genética , Carpas/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Antioxidantes/metabolismo , Doenças dos Peixes/microbiologia , Fator 2 Relacionado a NF-E2/metabolismo , Dieta , Antibacterianos/farmacologia , Aeromonas hydrophila/fisiologia , Proteínas de Peixes/genética , Ração Animal/análise
6.
J Fish Dis ; 46(1): 17-29, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36097971

RESUMO

A new strain of Paenibacillus polymyxa S3 with antagonistic effects on 11 major fish pathogens (especially Aeromonas hydrophila), but had no toxicity to grass carp, was screened from the sediment of fishponds. In vivo colonization studies showed that strain S3 could be colonized and distributed in the gill and abdomen of the grass carp. Bioassay results showed that the weight growth rate of grass carp in the strain S3 oral group (16.01%) and strain S3 immersion group (16.44%) was significantly higher than those of the control group (8.61%). At the same time, the activities of ACP, AKP, CAT and GSH-Px in the serum of grass carp in oral and immersion groups were significantly higher than those of the control group. In addition, the treatment with strain S3 could significantly upregulate the expression of the antioxidant-related genes and immune-related genes Keap1, Nrf2, C3, LZM, IgM, TLR-4 and MyD-88 in grass carp tissues. The challenge test showed that strain S3 treatment significantly increased the survival rate of grass carp infected with Aeromonas hydrophila. Whole genome sequencing analysis showed that strain S3 had 16 active metabolite gene clusters, indicating that it had abundant gene resources, which provided important support for its development for fish microecological preparations. In summary, a new strain of Paenibacillus polymyxa S3 with antibacterial activity against a variety of fish pathogens was screened in this study and its probiotic function was evaluated, proving its potential value in fisheries.


Assuntos
Carpas , Doenças dos Peixes , Paenibacillus polymyxa , Animais , Resistência à Doença , Paenibacillus polymyxa/genética , Proteína 1 Associada a ECH Semelhante a Kelch , Fator 2 Relacionado a NF-E2
7.
Angew Chem Int Ed Engl ; 62(27): e202304312, 2023 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-37137872

RESUMO

The metabolic reprogramming of tumors requires high levels of adenosine triphosphate (ATP) to maintain therapeutic resistance, posing a major challenge for photothermal therapy (PTT). Although raising the temperature helps in tumor ablation, it frequently leads to severe side effects. Therefore, improving the therapeutic response and promoting healing are critical considerations in the development of PTT. Here, we proposed a gas-mediated energy remodeling strategy to improve mild PTT efficacy while minimizing side effects. In the proof-of-concept study, a Food and Drug Administration (FDA)-approved drug-based hydrogen sulfide (H2 S) donor was developed to provide a sustained supply of H2 S to tumor sites, serving as an adjuvant to PTT. This approach proved to be highly effective in disrupting the mitochondrial respiratory chain, inhibiting ATP generation, and reducing the overexpression of heat shock protein 90 (HSP90), which ultimately amplified the therapeutic outcome. With the ability to reverse tumor thermotolerance, this strategy delivered a greatly potent antitumor response, achieving complete tumor ablation in a single treatment while minimizing harm to healthy tissues. Thus, it holds great promise to be a universal solution for overcoming the limitations of PTT and may serve as a valuable paradigm for the future clinical translation of photothermal nanoagents.


Assuntos
Nanopartículas , Neoplasias , Humanos , Terapia Fototérmica , Neoplasias/tratamento farmacológico , Temperatura , Linhagem Celular Tumoral , Nanopartículas/uso terapêutico , Fototerapia
8.
Small ; 18(15): e2200116, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35212462

RESUMO

Hypoxia is a hallmark of the tumor microenvironment (TME) that promotes tumor development and metastasis. Photodynamic therapy (PDT) is a promising strategy in the treatment of tumors, but it is limited by the lack of oxygen in TME. In this work, an O2 self-supply PDT system is constructed by co-encapsulation of chlorin e6 (Ce6) and a MnO2 core in an engineered ferritin (Ftn), generating a nanozyme promoted PDT nanoformula (Ce6/Ftn@MnO2 ) for tumor therapy. Ce6/Ftn@MnO2 exhibits a uniform small size (15.5 nm) and high stability due to the inherent structure of Ftn. The fluorescence imaging and immunofluorescence analysis demonstrate the pronounced accumulation of Ce6/Ftn@MnO2 in the tumors of mice, and the treatment significantly decreases the expression of hypoxia-inducible factor (HIF)-1α. The Ce6/Ftn@MnO2 nanoplatform exerts a more potent anti-tumor efficacy with negligible damage to normal tissues compared to the treatment with free Ce6. Moreover, the weak acidity and the presence of H2 O2 in TME significantly enhances the r1 relativity of Ce6/Ftn@MnO2 , resulting in a prominent enhancement of MRI imaging in the tumor. This bio-mimic Ftn strategy not only improves the in vivo distribution and retention of Ce6, but also enhances the effectiveness and precision of PDT by TME modulation.


Assuntos
Neoplasias , Fotoquimioterapia , Porfirinas , Animais , Linhagem Celular Tumoral , Ferritinas , Peróxido de Hidrogênio/química , Hipóxia/tratamento farmacológico , Compostos de Manganês/química , Camundongos , Neoplasias/tratamento farmacológico , Óxidos/química , Oxigênio/química , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/química , Porfirinas/química , Porfirinas/uso terapêutico , Microambiente Tumoral
9.
Opt Express ; 30(8): 12586-12595, 2022 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-35472892

RESUMO

The pulse duration of the near quarter-acoustic period (τa) is demonstrated in transient stimulated Brillouin scattering (SBS) pulse compression by the suppressing Stokes trailing-edge broadening at high intensities. A theoretical analysis reveals that the difficulty in attaining the transient compression limit is caused by the broadening of the Stokes trailing edge owing to insufficient pump depletion, and this undesirable phenomenon can be significantly suppressed by a high SBS gain coefficient. An average pulse duration of ∼1.05 τa was experimentally achieved in transient compression with a high-energy efficiency of over 30%. Benefiting from energy back conversion, compression below the transient SBS limit (< τa) also occurred when the pump peak power was increased to 150 MW.

10.
Opt Express ; 30(17): 30600-30610, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-36242160

RESUMO

Delayed self-heterodyne interferometry is a commonly used technique for the measurement of laser linewidth. It typically requires the use of a very long delay fiber when measuring narrow linewidth (especially linewidths in the kHz-range) lasers. The use of long fibers can result in system losses and the introduction of 1/f noise that causes spectral line broadening. In this paper, we present a calculation method for processing the output of a delayed self-heterodyne setup using a short length of delay fiber, to determine laser linewidth. The method makes use of pairs of data points (corresponding to adjacent maxima and/or minima) in the signal generated from the self-heterodyne setup to determine the laser linewidth. Here, the power ratio or amplitude difference of the signal at these data points is of importance. One of the key benefits of this method is that it avoids 1/f noise which would otherwise be introduced into the measurement through the application of long fibers. The experimental results highlight that the method has a high calculation accuracy. Furthermore, the capacity for the method to utilize different pairs of data points in the self-heterodyne output to determine the laser linewidth, imparts a high degree of flexibility and usability to the technique when applied to real-world measurements.

11.
Microb Pathog ; 169: 105646, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35716927

RESUMO

Aeromonas veronii AvX005 is a pathogenic bacterium with high toxicity to grass carp (Ctenopharyngodon idellus). The expression levels of g-type (goose-type lysozyme, Lys-g) and c-type lysozyme (chicken-type lysozyme, Lys-c) in the spleen of grass carp infected with AvX005 were significantly increased by approximately 4.5 times and 27 times, respectively. The recombinant proteins rLys-g and rLys-c produced in a recombinant expression system of Escherichia coli showed significant antibacterial activity against the pathogenic bacteria AvX005. A challenge test was conducted after rLys-g and rLys-c were expressed in grass carp L8824 liver cells, and compared with the survival rate of the control cells (46.3%), the survival rate of the experimental cells (77.6% for rLys-g and 68.6% for rLys-c) was significantly increased. Grass carp were infected with AvX005 on the second day after delivering pcDNA3.1-lys-g and pcDNA-lys-c with the Quil A/cholesterol/DDA/Carbopol (QCDC) adjuvant, and both pcDNA3.1-lys-g and pcDNA-lys-c provided 70% relative protection for grass carp. The activity of lysozyme and alkaline phosphatase in the serum of grass carp was significantly increased after injection of DNA. The expression of the immune factors IgM, C3 and IL8 in the kidney was upregulated to varying degrees for pcDNA3.1-lys-g and immune factors C3 and IgM was upregulated for pcDNA-lys-c. The results indicated that pcDNA3.1-lys-g and pcDNA-lys-c may be used as immunostimulants to protect grass carp from the pathogenic bacterium AvX005.


Assuntos
Carpas , Doenças dos Peixes , Infecções por Bactérias Gram-Negativas , Resinas Acrílicas , Adjuvantes Imunológicos/farmacologia , Aeromonas hydrophila/fisiologia , Aeromonas veronii , Animais , Carpas/metabolismo , Colesterol , Doenças dos Peixes/microbiologia , Imunidade Inata , Imunoglobulina M , Muramidase/genética , Muramidase/farmacologia , Saponinas de Quilaia
12.
Microb Pathog ; 166: 105488, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35367573

RESUMO

Many fishes infected with Pseudomonas plecoglossicida generally suffer from "visceral white spot disease" or even die. In this study, a dominant pathogen strain was isolated from the intestinal tract of diseased crucian carp in the Wangcheng Lake area, Changsha, and it was identified as P. plecoglossicida. The selected strain was a new strain named as P. plecoglossicida LQJ06.Strain LQJ06 basically colonized the intestine and poisoned zebrafish as show by fluorescent labelling. Pathological structural analysis of tissue sections indicated that the intestinal tract was seriously damaged, epithelial cells in the intestinal tissue were necrotic, intestinal villi were sloughed, liver cells were vacuolated, nuclei were pyknotic and shifted, and lymphocytes were proliferated in the spleen. P. plecoglossicida LQJ06 strain could invade and proliferate in the grass carp liver cell line L8824, which led to a stress response, including apoptosis. Cell morphology was changed owing to the toxicity of the culture supernatant of the LQJ06 strain, which mainly manifested as aggregation between cells, pyknosisd and slow growth or even death. An inactivated vaccine derived from P. plecoglossicida LQJ06 prepared in this study was safe and nontoxic to grass carp liver cells. Compared with those after oral administration, most of the cellular immune factors were expressed earlier and at a higher level after injection immunization. The intestinal tract and liver from zebrafish mainly expressed the IFN-γ2 and IL-1ß genes, respectively, after immunization. The upregulation of these immune-related genes proved that the vaccine could strengthen the immunity of zebrafish, induce inflammation and promote resistance to pathogenic infection. The results of these preliminary tests provide a scientific basis for further research on the prevention and control of P. plecoglossicida, and an essential preliminary basis for the development of an inactivated vaccine against P. plecoglossicida.


Assuntos
Carpas , Doenças dos Peixes , Animais , Doenças dos Peixes/prevenção & controle , Pseudomonas , Vacinas de Produtos Inativados , Virulência , Peixe-Zebra
13.
Opt Lett ; 47(20): 5360-5363, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36240362

RESUMO

Stimulated Brillouin scattering (SBS), with its advantages of low quantum defect and narrow gain bandwidth, has recently enabled an exciting path toward narrow-linewidth and low-noise lasers. Whereas almost all work to date has been in guided-wave configurations, adaptation to unguided Brillouin lasers (BLs) offers a greater capacity for power scaling, cascaded Stokes control, and greater flexibility for expanding wavelength range. Here, we report a diamond Brillouin laser (DBL) employing doubly resonant technology at 1064 nm. Brillouin output power of 22.5 W with a linewidth of 46.9 kHz is achieved. The background noise from the pump amplified spontaneous emission (ASE) is suppressed by 35 dB. The work represents a significant step toward realizing Brillouin oscillators that simultaneously have high power (tens-of-watts+) and kHz-linewidths.

14.
Angew Chem Int Ed Engl ; 61(4): e202114250, 2022 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-34800083

RESUMO

PtIV prodrugs can overcome resistance and side effects of conventional PtII anticancer therapies. By 19 F-labeling of a PtIV prodrug (Pt-FBA, FBA=p-fluorobenzoate), the activation under physiological conditions could be investigated. Unlike single-electron reductants, multi-electron agents can efficiently promote the two electrons reduction of PtIV to PtII . The activation of Pt-FBA in cell lysate is highly dependent upon the type of cancer cells. When administered to E. coli, Pt-FBA is reduced intracellularly and free FBA can shuttle out of the cell. The reduction rate greatly increases by inducing metallothionein overexpression and is lowered by addition of ZnII ions. When injected into mice, Pt-FBA undergoes fast reduction in the bloodstream accompanied by metabolic degradation of FBA; nevertheless, unreduced Pt-FBA can accumulate to detectable levels in liver and kidneys. The 19 F NMR approach has the advantage of avoiding the interference of all background signals.


Assuntos
Compostos Organoplatínicos/metabolismo , Pró-Fármacos/metabolismo , Animais , Fluoretos , Camundongos , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Compostos Organoplatínicos/administração & dosagem , Compostos Organoplatínicos/química , Pró-Fármacos/administração & dosagem , Pró-Fármacos/química
15.
Microb Pathog ; 161(Pt A): 105273, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34740811

RESUMO

The Streptomyces virginiae strain W18 was screened from soil, which exhibited broad-spectrum antibacterial activity against fish pathogens. Safety assays showed that strain W18 had no toxicity to fish. Additionally, strain W18 promoted the growth performance of Carassius auratus after feeding in feed mixed with bacteria for one month. Moreover, the activities of AKP, ACP, and SOD in the serum of C. auratus were significantly increased, while the activity of LZM did not greatly change. To detect the expression levels of the genes related to immune factors in the livers, kidneys, and spleens of C. auratus, qRT-PCR was performed. The expression levels of KEAP1, IL-8, TNF-α, IL-ß, and C3 were upregulated in all three organs compared to the control, but LZM expression was downregulated in the kidney. The challenge experiment illustrated that the probability of infection with Aeromonas veronii was reduced by 60% and 40% when C. auratus was fed with two different doses of strain W18 in advance. The whole genome of strain W18 was sequenced, and the gene clusters of secondary metabolites in strain W18 were analyzed by AntiSMASH. The results showed that strain W18 contained a total of 26 gene clusters, and functional annotation analysis was conducted by using the non-coding databases COG and KEGG. All of the above results indicated that the use of strain W18 as a feed additive could enhance the resistance of C. auratus toward pathogenic bacteria and disease. In conclusion, an antagonistic strain (W18) against fish pathogenic bacteria was obtained in this study, which is of great significance for finding new treatment methods for bacterial diseases in the aquaculture industry.


Assuntos
Aeromonas veronii/patogenicidade , Resistência à Doença , Doenças dos Peixes , Infecções por Bactérias Gram-Negativas , Streptomyces , Ração Animal , Animais , Antibiose , Doenças dos Peixes/microbiologia , Doenças dos Peixes/prevenção & controle , Carpa Dourada , Infecções por Bactérias Gram-Negativas/veterinária , Streptomyces/genética
16.
Inorg Chem ; 60(19): 14515-14519, 2021 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-34505770

RESUMO

Nanozyme is a class of artificial materials that possess enzyme-like activities and can overcome limitations of natural enzymes. However, controllability of the active sites, uniformity of the particles, and dispersion in the physiological media are still challenging for nanomaterial-based nanozymes. In this work, a protein-based nanozyme has been constructed by the encapsulation of hemin into the nanocavity of a recombinant human heavy chain ferritin (Ftn), generating a monodispersed peroxidase-mimetic nanozyme (hemin@Ftn). Hemin@Ftn possesses high peroxidase catalytic activity and high tolerance to the harsh environmental conditions, such as high temperature and chemical denaturant. Remarkably, hemin@Ftn can act as a colorimetric probe for the detection of tumor cells because it can selectively catalyze reactions in tumor cells. This protein-based nanozyme bridges the gap between natural enzymes and nanomaterial-based nanozymes by the incorporation of a catalytically active prosthetic group into a highly stable Ftn.


Assuntos
Ferritinas/química , Hemina/química , Nanoestruturas/química , Animais , Linhagem Celular , Humanos , Camundongos , Espectrofotometria Ultravioleta
17.
Int J Mol Sci ; 22(12)2021 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-34202990

RESUMO

Proteins that contain the FYVE zinc-finger domain are recruited to PtdIns3P-containing membranes, participating in numerous biological processes such as membrane trafficking, cytoskeletal regulation, and receptor signaling. However, the genome-wide distribution, evolution, and biological functions of FYVE-containing proteins are rarely reported for oomycetes. By genome mining of Phytophthora sojae, two proteins (PsFP1 and PsFP2) with a combination of the FYVE domain and the PX domain (a major phosphoinositide binding module) were found. To clarify the functions of PsFP1 and PsFP2, the CRISPR/Cas9-mediated gene replacement system was used to knock out the two genes respectively. Only heterozygous deletion mutants of PsFP1 were recovered, and the expression level of PsFP1 in the heterozygous knockout transformants was significantly down-regulated. These PsFP1 mutants showed a decrease in mycelial growth and pathogenicity and were more sensitive to hydrogen peroxide. These phenotypes were recovered to the level of wild-type by overexpression PsFP1 gene in the PsFP1 heterozygous knockout transformant. In contrast, deletion of PsFP2 had no significant effect on vegetative growth, asexual and sexual reproduction, pathogenicity, or oxidative stress sensitivity. PsFP1 was primarily localized in vesicle-like structures and both the FYVE and PX domains are important for its localization. Overall, our results indicate that PsFP1 plays an important role in the vegetative growth and virulence of P. sojae.


Assuntos
Estresse Oxidativo , Phytophthora/fisiologia , Proteínas/metabolismo , Dedos de Zinco , Sequência de Aminoácidos , Expressão Gênica , Fenótipo , Phytophthora/patogenicidade , Doenças das Plantas/parasitologia , Domínios Proteicos , Transporte Proteico , Proteínas/química , Proteínas/genética , Deleção de Sequência , Virulência/genética
18.
Opt Express ; 26(18): 23051-23060, 2018 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-30184961

RESUMO

A new stimulated Brillouin scattering (SBS) compression mechanism, quasi-steady-state SBS compression, in which the compression limit is one-tenth of the phonon lifetime with a high energy efficiency, is proposed and practically realized in this study. The feasibility of this approach is demonstrated experimentally, in which a compression of 0.36τB with an energy efficiency of 65% is achieved in a 3M Fluorinert Electronic Liquid FC-3283 and a compression output of 0.12τB (near-compression-limited) with an energy efficiency above 40% is obtained in acetone when the phonon lifetime to leading-edge to ratio is greater than 10. This ratio is identified experimentally as the key parameter in quasi-steady-state SBS compression. This work provides a practical approach to reliably generating one-tenth-phonon-lifetime pulses by quasi-steady-state SBS compression.

19.
Yao Xue Xue Bao ; 49(6): 807-12, 2014 Jun.
Artigo em Zh | MEDLINE | ID: mdl-25212024

RESUMO

This study is to investigate the protective effect of rosiglitazone (RSG) against learning and memory impairment of APP/PS1/tau transgenic mice. AD mice model was replicated by using 6-month APP/PS1/tau transgenic mice. The learning and memory ability of mice was evaluated by Morris water maze and Western blotting assays was applied to measure the phosphorylation and O-glycosylation of Tau and neurofilaments (NFs) protein. The results demonstrated that RSG could reverse the learning and memory deficits of 3 x Tg mice significantly. It was also found that RSG could suppress the hyperphosphorylation of Tau and NFs protein levels and increase the glycosylation expression of Tau and NFs proteins in 3 x Tg mice brain. Together, RSG ameliorates cognitive impairments of 3 x Tg mice via the alleviation of the hyperphosphorylated Tau and NFs proteins burden in the brain.


Assuntos
Aprendizagem/efeitos dos fármacos , Memória/efeitos dos fármacos , Tiazolidinedionas/farmacologia , Doença de Alzheimer , Peptídeos beta-Amiloides , Animais , Encéfalo/efeitos dos fármacos , Modelos Animais de Doenças , Glicosilação , Transtornos da Memória/tratamento farmacológico , Camundongos , Camundongos Transgênicos , Proteínas de Neurofilamentos/metabolismo , Fosforilação , Rosiglitazona , Proteínas tau/metabolismo
20.
Zhongguo Zhong Yao Za Zhi ; 39(19): 3846-9, 2014 Oct.
Artigo em Zh | MEDLINE | ID: mdl-25612452

RESUMO

OBJECTIVE: To observe the changes in Aß40, Aß42 and ADDLs in brains of 3 month-old APPswe/PS1dE9 double transgenic mice after six-month intervention with curcumin, in order to discuss the neuroprotective effect of curcumin. METHOD: APPswe/PS1dE9dtg mice were randomly divided into the model group, the Rosiglitazone group (10 mg x kg(-1) x d(-1)) and curcumin high (400 mg x kg9-1) x d(-1)), medium (200 mg x kg(-1) x d(-1)) and low (100 mg x kg(-1) x d(-1)) dosage groups, with C57/BL6J mice of the same age and the same background in the normal control group. After 6 months, the immunohistochemical staining (IHC) and the Western blot method were used to observe the changes in positive cell of Aß40, Aß42 and ADDLs in hippocampal CA1 area, their distribution and protein expressions. RESULT: Both of the immunohistochemical staining and the Western blot method showed more positive cell of Aß40, Aß42 and ADDLs in hippocampal CA1 area and higher protein expressions in the model group than the normal group (P < 0.01). IHC showed a lower result in the Rosiglitazone group than the model group (P < 0.05), while Western blot showed a much lower result (P < 0.01). The number of Aß40, Aß42 and ADDLs positive cells and the protein expressions decreased in the curcumin high group, the medium group showed a significant decrease (P < 0.01), and the low dose group also showed reductions in the protein expressions of Aß40 and Aß42. CONCLUSION: The six-month intervention with curcumin can significantly reduce the expressions of hippocampal Aß40, Aß42 and ADDLs in brains of APPswe/PS1dE9 double transgenic mice. Whether curcumin can impact Aß cascade reaction by down-regulating expressions of Aß40, Aß42 and ADDLs and show the neuroprotective effect needs further studies.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Curcumina/administração & dosagem , Fármacos Neuroprotetores/administração & dosagem , Extratos Vegetais/administração & dosagem , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/genética , Peptídeos beta-Amiloides/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Modelos Animais de Doenças , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA