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1.
Small ; : e2402649, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38949403

RESUMEN

The utilization of the organic-inorganic hybrid photocatalysts for water splitting has gained significant attention due to their ability to combine the advantages of both materials and generate synergistic effects. However, they are still far from practical application due to the limited understanding of the interactions between these two components and the complexity of their preparation process. Herein, a facial approach by combining a glycolated conjugated polymer with a TiO2-X mesoporous sphere to prepare high-efficiency hybrid photocatalysts is presented. The functionalization of conjugated polymers with hydrophilic oligo (ethylene glycol) side chains can not only facilitate the dispersion of conjugated polymers in water but also promote the interaction with TiO2-X forming stable heterojunction nanoparticles. An apparent quantum yield of 53.3% at 365 nm and a hydrogen evolution rate of 35.7 mmol h-1 g-1 is achieved by the photocatalyst in the presence of Pt co-catalyst. Advanced photophysical studies based on femtosecond transient absorption spectroscopy and in situ, XPS analyses reveal the charge transfer mechanism at type II heterojunction interfaces. This work shows the promising prospect of glycolated polymers in the construction of hybrid heterojunctions for photocatalytic hydrogen production and offers a deep understanding of high photocatalytic performance by such heterojunction photocatalysts.

2.
Hum Reprod ; 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39013119

RESUMEN

STUDY QUESTION: Can the density of the inner cell mass (ICM) be a new indicator of the quality of the human blastocyst? SUMMARY ANSWER: The densification index (DI) developed in this study can quantify ICM density and provide positive guidance for ploidy, pregnancy, and live birth. WHAT IS KNOWN ALREADY: In evaluating the quality of ICM, reproductive care clinics still use size indicators without further evaluation. The main disadvantage of this current method is that the evaluation of blastocyst ICM is relatively rough and cannot meet the needs of clinical embryologists, especially when multiple blastocysts have the same ICM score, which makes them difficult to evaluate further. STUDY DESIGN, SIZE, DURATION: This observational study included data from 2272 blastocysts in 1991 frozen-thawed embryo transfer (FET) cycles between January 2018 to November 2021 and 1105 blastocysts in 430 preimplantation genetic testing cycles between January 2019 and February 2023. PARTICIPANTS/MATERIALS, SETTING, METHODS: FET, ICSI, blastocyst culture, trophectoderm biopsy, time-lapse (TL) monitoring, and next-generation sequencing were performed. After preliminary sample size selection, the 11 focal plane images captured by the TL system were normalized and the spatial frequency was used to construct the DI of the ICM. MAIN RESULTS AND THE ROLE OF CHANCE: This study successfully constructed a quantitative indicator DI that can reflect the degree of ICM density in terms of fusion and texture features. The higher the DI value, the better the density of the blastocyst ICM, and the higher the chances that the blastocyst was euploid (P < 0.001) and that pregnancy (P < 0.001) and live birth (P = 0.005) were reached. In blastocysts with ICM graded B and blastocysts graded 4BB, DI was also positively associated with ploidy, pregnancy, and live birth (P < 0.05). ROC analysis showed that combining the Gardner scoring system with DI can more effectively predict pregnancy and live births, when compared to using the Gardner scoring system alone. LIMITATIONS, REASONS FOR CAUTION: Accurate calculation of the DI value places high demands on image quality, requiring manual selection of the clearest focal plane and exposure control. Images with the ICM not completely within the field of view cannot be used. The association between the density of ICM and chromosomal mosaicism was not evaluated. The associations between the density of ICM and different assisted reproductive technologies and different culture conditions in embryo laboratories were also not evaluated. Prospective studies are needed to further investigate the impact of ICM density on clinical outcomes. WIDER IMPLICATIONS OF THE FINDINGS: ICM density assessment is a new direction in blastocyst assessment. This study explores new ways of assessing blastocyst ICM density and develops quantitative indicators and a corresponding qualitative evaluation scheme for ICM density. The DI of the blastocyst ICM developed in this study is easy to calculate and requires only TL equipment and image processing, providing positive guidance for clinical outcomes. The qualitative evaluation scheme of ICM density can assist embryologists without TL equipment to manually evaluate ICM density. ICM density is a simple indicator that can be used in practice and is a good complement to the blastocyst scoring systems currently used in most centers. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the National Key Research & Development Program of China (2021YFC2700603). The authors report no financial or commercial conflicts of interest. TRIAL REGISTRATION NUMBER: N/A.

3.
Anal Biochem ; 691: 115553, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38697592

RESUMEN

We describe a microwave-assisted, methanol and acetic acid-free, inexpensive method for rapid staining of SDS-PAGE proteins. Only citric acid, benzoic acid, and Coomassie brilliant blue G-250 (CBG) were used. Microwave irradiation reduced the detection duration, and proteins in a clear background were visualized within 30 min of destaining, after 2 min of fixing and 12 min of staining. By using this protocol, comparable band intensities were obtained to the conventional methanol/acetic acid method.


Asunto(s)
Ácido Acético , Electroforesis en Gel de Poliacrilamida , Metanol , Microondas , Proteínas , Electroforesis en Gel de Poliacrilamida/métodos , Metanol/química , Proteínas/análisis , Ácido Acético/química , Coloración y Etiquetado/métodos , Colorantes de Rosanilina/química
4.
Int J Mol Sci ; 25(13)2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-39000482

RESUMEN

Plesiomonas shigelloides, a Gram-negative bacillus, is the only member of the Enterobacteriaceae family able to produce polar and lateral flagella and cause gastrointestinal and extraintestinal illnesses in humans. The flagellar transcriptional hierarchy of P. shigelloides is currently unknown. In this study, we identified FlaK, FlaM, FliA, and FliAL as the four regulators responsible for polar and lateral flagellar regulation in P. shigelloides. To determine the flagellar transcription hierarchy of P. shigelloides, the transcriptomes of the WT and ΔflaK, ΔflaM, ΔfliA, and ΔfliAL were carried out for comparison in this study. Quantitative Real-Time Polymerase Chain Reaction (qRT-PCR) and luminescence screening assays were used to validate the RNA-seq results, and the Electrophoretic Mobility Shift Assay (EMSA) results revealed that FlaK can directly bind to the promoters of fliK, fliE, flhA, and cheY, while the FlaM protein can bind directly to the promoters of flgO, flgT, and flgA. Meanwhile, we also observed type VI secretion system (T6SS) and type II secretion system 2 (T2SS-2) genes downregulated in the transcriptome profiles, and the killing assay revealed lower killing abilities for ΔflaK, ΔflaM, ΔfliA, and ΔfliAL compared to the WT, indicating that there was a cross-talk between the flagellar hierarchy system and bacterial secretion system. Invasion assays also showed that ΔflaK, ΔflaM, ΔfliA, and ΔfliAL were less effective in infecting Caco-2 cells than the WT. Additionally, we also found that the loss of flagellar regulators causes the differential expression of some of the physiological metabolic genes of P. shigelloides. Overall, this study aims to reveal the transcriptional hierarchy that controls flagellar gene expression in P. shigelloides, as well as the cross-talk between motility, virulence, and physiological and metabolic activity, laying the groundwork for future research into P. shigelloides' coordinated survival in the natural environment and the mechanisms that infect the host.


Asunto(s)
Proteínas Bacterianas , Flagelos , Perfilación de la Expresión Génica , Regulación Bacteriana de la Expresión Génica , Plesiomonas , Flagelos/metabolismo , Flagelos/genética , Plesiomonas/genética , Plesiomonas/metabolismo , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Transcriptoma , Regiones Promotoras Genéticas , Sistemas de Secreción Bacterianos/genética , Sistemas de Secreción Bacterianos/metabolismo , Transcripción Genética , Humanos
5.
Exp Appl Acarol ; 92(3): 403-421, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38489086

RESUMEN

Spider mites (Acari: Tetranychidae) are polyphagous pests of economic importance in agriculture, among which the two-spotted spider mite Tetranychus urticae Koch has spread widely worldwide as an invasive species, posing a serious threat to fruit tree production in China, including Beijing. The hawthorn spider mite, Amphitetranychus viennensis Zacher, is also a worldwide pest of fruit trees and woody ornamental plants. The cassava mite, Tetranychus truncatus Ehara, is mainly found in Asian countries, including China, Korea and Japan, and mainly affects fruit trees and agricultural crops. These three species of spider mites are widespread and serious fruit tree pests in Beijing. Rapid and accurate identification of spider mites is essential for effective pest and plant quarantine in Beijing orchard fields. The identification of spider mite species is difficult due to their limited morphological characteristics. Although the identification of insect and mite species based on PCR and real-time polymerase chain reaction TaqMan is becoming increasingly common, DNA extraction is difficult, expensive and time-consuming due to the minute size of spider mites. Therefore, the objective of this study was to establish a direct multiplex PCR method for the simultaneous identification of three common species of spider mites in orchards, A. viennensis, T. truncatus and T. urticae, to provide technical support for the differentiation of spider mite species and phytosanitary measures in orchards in Beijing. Based on the mitochondrial cytochrome c oxidase subunit I (COI) of the two-spotted spider mite and the cassava mite and the 18S gene sequence of the hawthorn spider mite as the amplification target, three pairs of specific primers were designed, and the primer concentrations were optimized to establish a direct multiplex PCR system for the rapid and accurate discrimination of the three spider mites without the need for DNA extraction and purification. The method showed a high sensitivity of 0.047 ng for T. truncatus and T. urticae DNA and 0.0002 ng for A. viennensis. This method eliminates the DNA extraction and sequencing procedures of spider mite samples, offers a possibility for rapid monitoring of multiple spider mites in an integrated microarray laboratory system, reducing the time and cost of leaf mite identification and quarantine monitoring in the field.


Asunto(s)
Reacción en Cadena de la Polimerasa Multiplex , Tetranychidae , Animales , Tetranychidae/genética , Reacción en Cadena de la Polimerasa Multiplex/métodos , Beijing , Complejo IV de Transporte de Electrones/genética
6.
Int Microbiol ; 26(4): 1103-1112, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37118189

RESUMEN

BACKGROUND: Jujube is an economically important fruit tree and native to China. Viral disease is a new threat to jujube production, and several new viruses have been identified infecting jujube plants. During our field survey, jujube mosaic disease was widely distributed in Beijing, but the associated causal agents are still unknown. METHODS: Small RNA deep sequencing was conducted to identify the candidate viruses associated with jujube mosaic. Further complete genome sequences of the viruses were cloned, and the genomic characterization of each virus was analyzed. The field distribution of these viruses was further explored with PCR/RT-PCR detection of field samples. RESULTS: Mixed infection of four viruses was identified in a plant sample with the symptom of mosaic and leaf twisting, including the previously reported jujube yellow mottle-associated virus (JYMaV), persimmon ampelovirus (PAmpV), a new badnavirus tentatively named jujube-associated badnavirus (JaBV), and a new secovirus tentatively named jujube-associated secovirus (JaSV). PAmpV-jujube was 14,093 nt in length with seven putative open reading frames (ORFs) and shared highest (79.4%) nucleotide (nt) sequence identity with PAmpV PBs3. Recombination analysis showed that PAmpV-jujube was a recombinant originating from plum bark necrosis stem pitting-associated virus isolates nanjing (KC590347) and bark (EF546442). JaBV was 6449 bp in length with conserved genomic organization typical of badnaviruses. The conserved RT and RNAse H region shared highest 67.6% nt sequence identity with jujube mosaic-associated virus, which was below the 80% nt sequence identity value used as the species demarcation threshold in Badnavirus. The genome of JaSV composed of two RNA molecules of 5878 and 3337 nts in length, excluding the polyA tails. Each genome segment contained one large ORF that shared homology and phylogenetic identity with members of the family Secoviridae. Field survey showed JYMaV and JaBV were widely distributed in jujube trees in Beijing. CONCLUSION: Two new viruses were identified from jujube plants, and mixed infections of JYMaV and JaBV were common in jujube in Beijing.


Asunto(s)
Badnavirus , Coinfección , Ziziphus , Filogenia , Ziziphus/genética , Coinfección/genética , Frutas , Genoma Viral , Badnavirus/genética , ARN
7.
Nanotechnology ; 33(24)2022 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-35240594

RESUMEN

A novel CaIn2S4with three-dimensional octahedral nano-blocks (ONBs) are successfully synthesized on fluorine-doped tin oxide (FTO) substrate by a simple hydrothermal method. The CaIn2S4ONBs are uniform grown and scattered on the whole FTO substrate with high regular and symmetric morphology as well as average diagonal length of about 600 nm. Based on the as-synthesized CaIn2S4ONBs, a photodetector (PD) is fabricated. Satisfyingly, it is found that the CaIn2S4ONBs PD achieves a broad-band response ranging from ultraviolet (UV) to visible ( vis) light at zero bias voltage. It is also significant that the CaIn2S4ONBs PD enables a fast response, in which the rise time and decay time are less than 0.15 and 0.2 s, respectively. Furthermore, the morphological evolution of the CaIn2S4ONBs and plausible UV/vis detection mechanism of the CaIn2S4ONBs PD are discussed.

8.
Nanotechnology ; 32(43)2021 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-34284363

RESUMEN

Bismuth telluride (Bi2Te3), as an emerging two-dimensional (2D) material, has attracted extensive attention from scientific researchers due to its excellent optoelectronic, thermoelectric properties and topological structure. However, the application research of Bi2Te3mainly focuses on thermoelectric devices, while the research on optoelectronic devices is scarce. In this work, the morphology evolution and growth mechanism of 2D Bi2Te3nanosheets with a thickness of 12 ± 3 nm were systematically studied by solvothermal method. Then, the Bi2Te3nanosheets were annealed at 350 °C for 1 h and applied to self-powered photoelectrochemical-type broadband photodetectors. Compared with the as-synthesized Bi2Te3photodetector, the photocurrent of the photodetector based on the annealed Bi2Te3is significantly enhanced, especially enhanced by 18.3 times under near-infrared light illumination. Furthermore, the performance of annealed Bi2Te3photodetector was systematically studied. The research results show that the photodetector not only has a broadband response from ultraviolet to near-infrared (365-850 nm) under zero bias voltage, but also obtains the highest responsivity of 6.6 mA W-1under green light with an incident power of 10 mW cm-2. The corresponding rise time and decay time are 17 ms and 20 ms, respectively. These findings indicate that annealed Bi2Te3nanosheets have great potential to be used as self-powered high-speed broadband photodetectors with high responsivity.

9.
Biochem Biophys Res Commun ; 526(3): 721-727, 2020 06 04.
Artículo en Inglés | MEDLINE | ID: mdl-32253032

RESUMEN

The nucleocapsid protein (NC) of human immunodeficiency virus type 1 (HIV-1) is a small, highly basic nucleic acid (NA)-binding protein with two CCHC zinc-finger motifs. In this study, we report for the first time, to our knowledge, that thermal stressed HIV-1 NCp7 maintained NA-binding activity. About 41.3% of NCp7 remained soluble after incubated at 100 °C for 60 min, and heat-treated NCp7 maintained its abilities to bind to HIV-1 packaging signal (Psi) and the stem-loop 3 of the Psi. At high or very high degrees of sequence occupancy, NCp7 inhibited first-strand cDNA synthesis catalyzed by purified HIV-1 reverse transcriptase, and heat-treated NCp7 maintained the inhibition. Moreover, both EDTA-treated and H23K + H44K double mutant of NCp7 inhibited first-strand cDNA synthesis, demonstrating that the NA-binding activity of NCp7 at high NC:NA ratios is independent on its zinc-fingers. These results may benefit further investigations of the structural stability and function of NCp7 in viral replication.


Asunto(s)
VIH-1/química , ARN Viral/química , Productos del Gen gag del Virus de la Inmunodeficiencia Humana/química , Secuencia de Aminoácidos , Sitios de Unión , ADN Complementario/biosíntesis , Escherichia coli , Transcriptasa Inversa del VIH/metabolismo , Respuesta al Choque Térmico , Humanos , Mutación , Unión Proteica , Replicación Viral , Dedos de Zinc
10.
Arch Biochem Biophys ; 679: 108187, 2020 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-31706880

RESUMEN

Macrophages play a pivotal role in the defense response against harmful pathogens and stimuli by releasing various pro-inflammatory mediators. However, overproduction of pro-inflammatory mediators will do harm to the organism and cause inflammation-associated diseases. Omentin-1, which is a newly discovered adipokine, is specifically expressed in omental adipose tissue. Recent studies have found correlations between omentin-1 and insulin resistance, diabetes, obesity, inflammation, atherosclerosis, bone metabolism, and tumor cell proliferation. Some studies have shown that the association between omentin-1, insulin resistance, and inflammation might suggest that omentin-1 plays an important role in chronic inflammatory diseases. In this study, we found that omentin-1 inhibited LPS-induced expression of inflammatory mediators and pro-inflammatory cytokines in macrophages. Furthermore, omentin-1 inhibited activation of the NF-κB pathway by suppressing both nuclear p65 accumulation and transfected NFκB promoter activity. Importantly, omentin-1 increased nuclear translocation of Nrf2. Our findings demonstrate that omentin-1 exerts anti-inflammatory effects on LPS-induced macrophages and has potential implication in the treatment of inflammation-associated diseases.


Asunto(s)
Lectinas/farmacología , Lipopolisacáridos/farmacología , Activación de Macrófagos/efectos de los fármacos , Factor 88 de Diferenciación Mieloide/metabolismo , FN-kappa B/metabolismo , Transducción de Señal/efectos de los fármacos , Receptor Toll-Like 4/metabolismo , Ciclooxigenasa 2/metabolismo , Citocinas/metabolismo , Dinoprostona/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Factor 2 Relacionado con NF-E2/metabolismo , Óxido Nítrico/biosíntesis , Óxido Nítrico Sintasa de Tipo II/metabolismo , Células U937
11.
Biochem Biophys Res Commun ; 510(3): 472-478, 2019 03 12.
Artículo en Inglés | MEDLINE | ID: mdl-30737028

RESUMEN

Retroviral nucleocapsid (NC) proteins are multifunctional nucleic acid binding proteins, playing critical roles in essentially every step of the viral replication cycle. As a small, basic protein, NC contains one or two highly conserved zinc-finger domains, each having an invariant CCHC motif, flanked by basic residues. In this study, we report for the first time, to our knowledge, the thermostable property of equine infectious anemia virus (EIAV) NCp11. About 43% of purified NCp11 remained soluble after incubation at 100 °C for 60 min, and heat-treated NCp11 maintained its abilities to bind to the E. coli RNA and the EIAV packaging signal sequence. At a very high degree of sequence occupancy, NCp11 inhibited first-strand cDNA synthesis catalyzed by either a commercial or the purified EIAV reverse transcriptase, and heat-treated NCp11 still inhibited the first-strand cDNA synthesis. We also found that protein concentrations, at a range from 0.1 to 0.9 µg/µl, have not affected the NCp11 thermostability significantly. However, NCp11 at acidic pH was more thermostable. Our findings highlight a new feature of the NC protein. Detailed understanding of NC's properties and functions will facilitate the development of effective and rational therapeutic strategies against retroviruses.


Asunto(s)
Proteínas de la Nucleocápside/química , Proteínas de la Nucleocápside/metabolismo , ADN Complementario/biosíntesis , Ácido Edético , Calor , Concentración de Iones de Hidrógeno , Estabilidad Proteica , ARN/metabolismo
12.
Regul Toxicol Pharmacol ; 106: 1-6, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31009652

RESUMEN

Residues and dietary risk assessment of tetraconazole and bifenazate were investigated in strawberry under greenhouse conditions using high performance liquid chromatography (HPLC-DAD) after QuEChERs extraction in Beijing of China. The effects of different processing factors on the two pesticides were studied. The recoveries of tetraconazole and bifenazate were 87.0% and 89.1%, respectively. The dissipation curves of tetraconazole and bifenazate were in accordance with the first-order kinetic equation and the half-life were 5.92 d and 5.58 d, respectively. When the pre-harvest interval (PHI) was 3 d, the risk quotient (RQs) of both pesticides was less than 100%. Although soaking was a poor way to remove the two pesticides and heating at high temperatures increases the concentration of both pesticides, the residues of two pesticides can be effectively removed by washing after soaking. The results of dietary intake assessment indicated that potential dietary risk caused by tetraconazole and bifenazate in strawberry were acceptable for Chinese consumers.


Asunto(s)
Carbamatos/análisis , Clorobencenos/análisis , Contaminación de Alimentos/análisis , Fragaria/química , Hidrazinas/análisis , Residuos de Plaguicidas/análisis , Triazoles/análisis , Adolescente , Adulto , Anciano , Carbamatos/efectos adversos , Niño , Preescolar , China , Clorobencenos/efectos adversos , Exposición Dietética , Femenino , Humanos , Hidrazinas/efectos adversos , Masculino , Persona de Mediana Edad , Residuos de Plaguicidas/efectos adversos , Medición de Riesgo , Triazoles/efectos adversos , Adulto Joven
13.
J Insect Sci ; 19(4)2019 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-31268547

RESUMEN

In recent years, we found that Hishimonus lamellatus Cai et Kuoh is a potential vector of jujube witches'-broom phytoplasma. However, little is known about the anatomy and histology of this leafhopper. Here, we examined histology and ultrastructure of the digestive system of H. lamellatus, both by dissecting and by semi- and ultrathin sectioning techniques. We found that the H. lamellatus digestive tract consists of an esophagus, a filter chamber, a conical midgut and midgut loop, Malpighian tubules, an ileum, and a rectum. Furthermore, both the basal region of the filter chamber epithelium and the apical surface of the midgut epithelium have developed microvilli. We also identify the perimicrovillar membrane, which ensheaths the microvilli of midgut loop enterocyte, and the flame-like luminal membrane, which covers the microvilli of the conical midgut epithelium. In addition, H. lamellatus has the principal and accessory salivary glands. Our observations also showed that the endoplasmic reticulum, mitochondria, and secretory granules were all highly abundant in the secretory cells of the principal salivary glands, while the accessory glands consist of only one ovate or elbow-like acinus. We also briefly contrast the structure of the gut of H. lamellatus with those of other leafhopper species. These results intend to offer help for the future study on the histological and subcellular levels of phytopathogen-leafhopper relationships, including transmission barriers and the binding sites of pathogens and other microorganisms within their leafhopper vectors.


Asunto(s)
Hemípteros/ultraestructura , Túbulos de Malpighi/ultraestructura , Animales , Tracto Gastrointestinal/ultraestructura , Microscopía Electrónica de Transmisión , Glándulas Salivales/ultraestructura
14.
Biochem Biophys Res Commun ; 486(3): 712-719, 2017 05 06.
Artículo en Inglés | MEDLINE | ID: mdl-28342872

RESUMEN

The conjugation of small ubiquitin-like modifier (SUMO) to the target protein, namely, SUMOylation, is involved in the regulation of many important biological events including host-pathogen interaction. Some viruses have evolved to exploit the host SUMOylation machinery to modify their own protein. Retroviral Gag protein plays critical roles in the viral life cycle. The HIV-1 p6 and the Moloney murine leukemia virus CA have been reported to be conjugated with SUMO. In this study, we report for the first time, to our knowledge, the covalent conjugation of equine infectious anemia virus (EIAV) Gag with SUMO. The C-terminal p9 domain of Gag is a main target for SUMOylation and SUMO is attached to multiple sites of p9, including K30 whose mutation abolished p9 SUMOylation completely. The SUMOylation of p9, but not the p9-K30 mutant, was also detected in equine fibroblastic cells ATCC® CCL-57™. Ubc9 and its C93 residue are indispensable for the SUMOylation of p9. Using confocal microscopy, it is found that EIAV Gag localizes primarily, if not exclusively, in the cytoplasm of the cell and the co-localization of EIAV Gag with Ubc9 was observed. Our findings that EIAV Gag is SUMOylated at p9-K30, together with previous findings on the defects of p9-K30 mutant in viral DNA translocation from cytoplasm to the nucleus, suggests that SUMOylation of Gag may be involved in such functions.


Asunto(s)
Productos del Gen gag/genética , Virus de la Anemia Infecciosa Equina/genética , Lisina/metabolismo , Proteína SUMO-1/genética , Enzimas Ubiquitina-Conjugadoras/genética , Secuencia de Aminoácidos , Animales , Línea Celular , Escherichia coli/genética , Escherichia coli/metabolismo , Fibroblastos/metabolismo , Fibroblastos/virología , Regulación de la Expresión Génica , Productos del Gen gag/metabolismo , Células HEK293 , Caballos , Interacciones Huésped-Patógeno , Humanos , Virus de la Anemia Infecciosa Equina/metabolismo , Mutación , Dominios Proteicos , Proteína SUMO-1/metabolismo , Transducción de Señal , Sumoilación , Enzimas Ubiquitina-Conjugadoras/metabolismo
15.
J Med Virol ; 89(11): 2011-2019, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-28639696

RESUMEN

Some viruses have evolved to exploit the host SUMOylation system to regulate their own replication. Kaposi's sarcoma-associated herpesvirus (KSHV) encodes K-bZIP, a SUMO E3 ligase catalyzing the SUMOylation of viral and host proteins. KSHV also encodes replication and transcriptional activator (RTA), a SUMO-targeted ubiquitin ligase catalyzing the ubiquitination of SUMOylated proteins and targeting them for degradation. Using chronic KSHV-infected TRE × BCBL-1 RTA cells, the expression kinetics of K-bZIP and RTA, and the global SUMOylation level were detected. The endogenous K-bZIP protein increased dramatically after the induction of the RTA gene that is tetracycline responsive, but then decreased rapidly after peaking at 8 h post tetracycline treatment. Consistently, the global SUMO-conjugated proteins increased and remained at high levels until 8 h, and decreased afterward, correlating with the expression kinetics of RTA and K-bZIP. In luciferase reporter assays, transfection of 293T cells with SUMO2 expression plasmid reduced the RTA transactivations of immediate-early genes k8, orf45, and orf50, but enhanced the RTA transactivations of other viral genes including orf57, pan, k2, orf8, and orf73. These results indicated that KSHV might regulate gene expression and viral replication schedule through modulation of the global SUMOylation level, probably via RTA, and RTA-regulated K-bZIP.


Asunto(s)
Regulación Viral de la Expresión Génica , Expresión Génica , Herpesvirus Humano 8/genética , Herpesvirus Humano 8/fisiología , Sumoilación , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/metabolismo , Línea Celular , Replicación del ADN , Células HEK293 , Humanos , Proteínas Inmediatas-Precoces/genética , Proteínas Inmediatas-Precoces/metabolismo , Regiones Promotoras Genéticas , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Tetraciclina/farmacología , Transactivadores/genética , Transactivadores/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Activación Transcripcional , Proteínas Virales/genética , Proteínas Virales/metabolismo , Activación Viral , Replicación Viral
16.
Pestic Biochem Physiol ; 142: 91-101, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29107253

RESUMEN

To investigate the insecticidal mechanism of cantharidin, a promising biological pesticide substance from blister beetle, on Sf9 cells, a cultured cell line derived from fall armyworm, Spodoptera frugiperda, we preliminary studied the attribution of Bax channel and mitochondrial permeability transition pore on cantharidin-induced mitochondrial apoptosis signal pathway. Changes in cell morphology, activity of mitochondrial dehydrogenases, release of cytochrome C and mitochondrial transmembrane potential were detected when the two channels were blocked by specific inhibitors, Bax channel blocker and cyclosporin A. Results showed that cantharidin-induced apoptotic features, including changes in the cell morphology, release of cytochrome C and decrease in mitochondrial transmembrane potential could be significantly inhibited by Bax channel blocker, while cyclosporin A accelerated the downward trend of mitochondrial dehydrogenases activity and caused a decrease of Ca2+ in mitochondria. In summary, Bax might be necessary but not exclusively for the apoptosis induced by cantharidin and the attribution of these channels seems to be more complexity.


Asunto(s)
Apoptosis , Cantaridina/toxicidad , Proteínas de Insectos/metabolismo , Mitocondrias/efectos de los fármacos , Proteínas de Transporte de Membrana Mitocondrial/metabolismo , Spodoptera/metabolismo , Proteína X Asociada a bcl-2/metabolismo , Animales , Citocromos c/metabolismo , Proteínas de Insectos/genética , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Mitocondrias/metabolismo , Proteínas de Transporte de Membrana Mitocondrial/efectos de los fármacos , Poro de Transición de la Permeabilidad Mitocondrial , Células Sf9 , Spodoptera/citología , Spodoptera/genética , Proteína X Asociada a bcl-2/genética
17.
Phys Chem Chem Phys ; 18(5): 4144-53, 2016 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-26782061

RESUMEN

A room temperature successive ionic layer adsorption and reaction (SILAR) method is introduced for fabricating quantum dots-on-wide bandgap semiconductors. Detailed exploration of how SILAR begins and proceeds is performed by analyzing changes in the electronic structure of related elements at interfaces by X-ray photoelectric spectroscopy, together with characterization of optical properties and X-ray diffraction. The distribution of PbS QDs on ZnO, which is critical for optoelectrical applications of PbS with a large dielectric constant, shows a close relationship with the dipping order. A successively deposited PbS QDs layer is obtained when the sample is first immersed in Na2S solution. This is reasonable because the initial formation of different chemical bonds on ZnO nanorods is closely related to dangling bonds and defect states on surfaces. Most importantly, dipping order also affects their optoelectrical characteristics greatly, which can be explained by the heterojunction energy band structure related to the interface. The formation mechanism for PbS QDs on ZnO is confirmed by the fact that the photovoltaic diode device performance is closely related to the dipping order. Our atomic-scale understanding emphasises the fundamental role of surface chemistry in the structure and tuning of optoelectrical properties, and consequently in devices.

18.
J Gen Virol ; 96(Pt 7): 1883-9, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25783474

RESUMEN

The open reading frame 45 (ORF45) of the Kaposi's sarcoma-associated herpesvirus (KSHV) is an immediate-early phosphorylated tegument protein critical for viral escape from host immune surveillance. Its expression is upregulated by the viral replication and transcription activator (RTA), a key protein that controls the switch from latency to lytic replication. We report here that ORF45 expression was not only upregulated by RTA, but ORF45 could also be degraded by RTA in a proteasome-dependent manner. The ORF45 was activated by RTA via activation of the ORF45 promoter, and the promoter region from nt 69 271 to nt 69 026 was involved. In chronic KSHV infected TRE-BCBL-1 RTA cells, the endogenous ORF45 protein increased dramatically after the induction of RTA expression, but then decreased rapidly after 8 h post-induction. Our study suggests that RTA might control the kinetics of viral replication through fine-tuning of the level of ORF45 and other viral/host proteins.


Asunto(s)
Regulación Viral de la Expresión Génica , Herpesvirus Humano 8/fisiología , Proteínas Inmediatas-Precoces/metabolismo , Transactivadores/metabolismo , Línea Celular , Humanos , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteolisis , Transcripción Genética
19.
J Econ Entomol ; 108(5): 2443-9, 2015 10.
Artículo en Inglés | MEDLINE | ID: mdl-26453733

RESUMEN

The insect family Cicadellidae includes economically important vectors of plant pathogens. Hishimonus sellatus (Uhler) transmits jujube witches'-broom (JWB). Currently, H. sellatus and Hishimonus lamellatus Cai et Kuoh are observed to co-occur at the same locality on jujube. H. lamellatus is now suspected to be a JWB vector. As such, correct identification of Hishimonus species present in vineyards is essential for epidemiological surveys. However, traditional identification of Hishimonus by morphology is limited to the adult male. We provide a comprehensive description of morphological and molecular tools for discriminating between H. sellatus and H. lamellatus, for use in identification and monitoring of the two Hishimonus species and studies of their plant hosts. A rapid and inexpensive method is introduced to identify H. sellatus and H. lamellatus occurring in jujube orchards. This method is based on amplification of mitochondrial cytochrome oxidase I (COI) gene, using PCR with multiplexed, species-specific primers. The reliability of this new method has been tested on different populations from different sites in Beijing region of China.


Asunto(s)
Complejo IV de Transporte de Electrones/genética , Hemípteros/clasificación , Hemípteros/genética , Proteínas de Insectos/genética , Proteínas Mitocondriales/genética , Reacción en Cadena de la Polimerasa Multiplex/métodos , Animales , China , Complejo IV de Transporte de Electrones/metabolismo , Hemípteros/metabolismo , Proteínas de Insectos/metabolismo , Masculino , Proteínas Mitocondriales/metabolismo , Análisis de Secuencia de ADN , Ziziphus/crecimiento & desarrollo
20.
Zhonghua Yi Xue Za Zhi ; 94(29): 2290-2, 2014 Aug 05.
Artículo en Zh | MEDLINE | ID: mdl-25391874

RESUMEN

OBJECTIVE: To distinguish the expressions of matrix metallo-poteinase and aquaporin in peritumor edematous zone and normal brain tissue for different pathological levels of glioma and explore the relationship of glioma cell invasiveness and brain edema. METHODS: The immunohistochemical method of SP was employed to detect the expressions of aquaporin-4 (AQP-4), matrix metallo-proteinase-2 (MMP-2) and matrix metallo-proteinase-14 (MMP-14) in glioma and normal brain tissue. Due to a rarity of glioma Grades I and II, grades I and II glioma were pooled into low malignancy group (LMG) and grades III and IV into high malignancy group (HMG). The software program SPSS 11.0 was used for Kolmogorov-Smirnov test of independent samplets. The differences were detected between normal brain tissue and LMG and HMG. Also the relationship of AQP4, MMP-2 and MMP-14 was analyzed. RESULTS: With the advancing pathological grades of glioma, the expression of AQP-4, MMP-2 and MMP-14 were higher in positive areas. There were significant deviations among 3 groups. CONCLUSION: The expressions of AQP-4, MMP-2 and MMP-14 in normal brain tissue and all levels of glioma edema are positively correlated. And there is a close correlation between glioma invasiveness and edema extent.


Asunto(s)
Acuaporina 4/metabolismo , Edema Encefálico/metabolismo , Neoplasias Encefálicas/metabolismo , Glioma/metabolismo , Metaloproteinasa 14 de la Matriz/metabolismo , Metaloproteinasa 2 de la Matriz/metabolismo , Humanos , Metaloproteinasa 9 de la Matriz
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