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1.
Proc Natl Acad Sci U S A ; 121(22): e2402911121, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38776366

RESUMO

Leaf yellowing is a well-known phenotype that attracts phloem-feeding insects. However, it remains unclear how insect-vectored plant pathogens induce host leaf yellowing to facilitate their own transmission by insect vectors. Here, we report that an effector protein secreted by rice orange leaf phytoplasma (ROLP) inhibits chlorophyll biosynthesis and induces leaf yellowing to attract leafhopper vectors, thereby presumably promoting pathogen transmission. This effector, designated secreted ROLP protein 1 (SRP1), first secreted into rice phloem by ROLP, was subsequently translocated to chloroplasts by interacting with the chloroplastic glutamine synthetase (GS2). The direct interaction between SRP1 and GS2 disrupts the decamer formation of the GS2 holoenzyme, attenuating its enzymatic activity, thereby suppressing the synthesis of chlorophyll precursors glutamate and glutamine. Transgenic expression of SRP1 in rice plants decreased GS2 activity and chlorophyll precursor accumulation, finally inducing leaf yellowing. This process is correlated with the previous evidence that the knockout of GS2 expression in rice plants causes a similar yellow chlorosis phenotype. Consistently, these yellowing leaves attracted higher numbers of leafhopper vectors, caused the vectors to probe more frequently, and presumably facilitate more efficient phytoplasma transmission. Together, these results uncover the mechanism used by phytoplasmas to manipulate the leaf color of infected plants for the purpose of enhancing attractiveness to insect vectors.


Assuntos
Cloroplastos , Glutamato-Amônia Ligase , Hemípteros , Insetos Vetores , Oryza , Phytoplasma , Folhas de Planta , Animais , Hemípteros/microbiologia , Glutamato-Amônia Ligase/metabolismo , Glutamato-Amônia Ligase/genética , Phytoplasma/fisiologia , Folhas de Planta/microbiologia , Folhas de Planta/metabolismo , Oryza/microbiologia , Oryza/genética , Insetos Vetores/microbiologia , Cloroplastos/metabolismo , Doenças das Plantas/microbiologia , Clorofila/metabolismo , Plantas Geneticamente Modificadas , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética
2.
J Environ Sci (China) ; 123: 367-386, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36521999

RESUMO

Emissions from mobile sources and stationary sources contribute to atmospheric pollution in China, and its components, which include ultrafine particles (UFPs), volatile organic compounds (VOCs), and other reactive gases, such as NH3 and NOx, are the most harmful to human health. China has released various regulations and standards to address pollution from mobile and stationary sources. Thus, it is urgent to develop online monitoring technology for atmospheric pollution source emissions. This study provides an overview of the main progress in mobile and stationary source monitoring technology in China and describes the comprehensive application of some typical instruments in vital areas in recent years. These instruments have been applied to monitor emissions from motor vehicles, ships, airports, the chemical industry, and electric power generation. Not only has the level of atmospheric environment monitoring technology and equipment been improving, but relevant regulations and standards have also been constantly updated. Meanwhile, the developed instruments can provide scientific assistance for the successful implementation of regulations. According to the potential problem areas in atmospheric pollution in China, some research hotspots and future trends of atmospheric online monitoring technology are summarized. Furthermore, more advanced atmospheric online monitoring technology will contribute to a comprehensive understanding of atmospheric pollution and improve environmental monitoring capacity.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Compostos Orgânicos Voláteis , Humanos , Poluentes Atmosféricos/análise , Poluição do Ar/análise , China , Monitoramento Ambiental , Material Particulado/análise , Tecnologia , Emissões de Veículos/análise , Compostos Orgânicos Voláteis/análise
3.
Sensors (Basel) ; 21(1)2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33466240

RESUMO

Conventional strategies for determining phosphate concentration is limited in efficiency due to the cost, time, and labor that is required in laboratory analysis. Therefore, an on-site and rapid detection sensor for phosphate is urgently needed to characterize phosphate variability in a hydroponic system. Cobalt (Co) is a highly sensitive metal that has shown a selectivity towards phosphate to a certain extent. A disposable phosphate sensor based on the screen-printed electrode (SPE) was developed to exploit the advantages of Co-nanoparticles. A support vector machine regression model was established to predict the concentration of phosphate in the hydroponic solutions. The results showed that Co-nanoparticles improve the detection limit of the sensor in the initial state. Meanwhile, the corrosion of Co-nanoparticles leads to a serious time-drift and instability of the electrodes. On the other hand, the coefficient of variation of the disposable phosphate detection chip is 0.4992%, the sensitivity is 33 mV/decade, and the linear range is 10-1-10-4.56 mol/L. The R2 and mean square error of the buffer-free sensor in the hydroponic solution are 0.9792 and 0.4936, respectively. In summary, the SPE modified by the Co-nanoparticles is a promising low-cost sensor for on-site and rapid measurement of the phosphate concentration in hydroponic solutions.

4.
Sensors (Basel) ; 20(3)2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31979192

RESUMO

Micro-Cantilever (MCL) is a thin film structure that is applied for aerosol particle mass sensing. Several modifications to the rectangular MCL (length-to-width ratio, slots at the anchor, serrations at its side edges) are made to deduce the role and influence of the shape of rectangular MCL-based aerosol mass sensors and reduce gas damping. A finite element fluid-structure interaction model was used to investigate the performance of MCL. It is found that (I) the mass sensitivity and quality factor decline with the increasing of length-to-width ratio which alters the resonant frequency of the MCL. The optimum conditions, including the length-to-width ratio (σlw = 5) and resonant frequency (f0 = 540.7 kHz) of the MCL, are obtained with the constant surface area (S = 45,000 µm2) in the frequency domain ranging from 0 to 600 kHz. (II) The slots can enhance the read-out signal and bring a small Q factor drop. (III) The edge serrations on MCL significantly reduce the gas damping. The results provide a reference for the design of aerosol mass sensor, which makes it possible to develop aerosol mass sensor with high frequency, sensitivity, and quality.

5.
Clin Sci (Lond) ; 133(2): 381-392, 2019 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-30626729

RESUMO

Long non-coding RNAs (lncRNAs) have been reported to play a vital role in non-small-cell lung cancer (NSCLC). ZEB1-AS1 overexpression predicts a poor prognosis in osteosarcoma and colorectal cancers. In the current study, we determined the clinical significance and prognostic value of ZEB1-AS1 in patients with NSCLC. The expression of ZEB1-AS1 and inhibitor of differentiation-1 (ID1) was measured using qRT-PCR and Western blot. Cell growth, migration, and invasion were determined using colony formation assays, Transwell assay, and flow cytometry, respectively. Tumor growth was determined with a xenograft model. ZEB1-AS1 was significantly up-regulated in NSCLC tissues compared with normal samples. ZEB1-AS1 overexpression was significantly associated with advanced tumor, lymph node, and metastases (TNM) stage and tumor size, as well as poorer overall survival. Moreover, ZEB1-AS1 knockdown inhibited NSCLC cell proliferation and migration, and promoted cell apoptosis. In addition, a chromatin immunoprecipitation assay revealed that ZEB1-AS1 interacted with STAT3, thereby repressing ID1 expression. Furthermore, rescue experiments indicated that ZEB1-AS1 functioned as an oncogene partly by repressing ID1 in NSCLC cells. Taken together, our findings indicate that ZEB1-AS1 serves as a promising therapeutic target to predict the prognosis of NSCLC.


Assuntos
Apoptose , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Movimento Celular , Proteína 1 Inibidora de Diferenciação/metabolismo , Neoplasias Pulmonares/metabolismo , RNA Longo não Codificante/metabolismo , Animais , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Proteína 1 Inibidora de Diferenciação/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Prognóstico , RNA Longo não Codificante/genética , Transdução de Sinais
6.
Respir Res ; 19(1): 197, 2018 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-30290817

RESUMO

BACKGROUND: Potential relationship between serum soluble programmed cell death ligand 1 and prognosis of small cell lung cancer is not well explored. The aim of the study was to reveal the prognostic significance of serum soluble programmed cell death ligand 1 in patients with small cell lung cancer. METHODS: A total of 250 small cell lung cancer patients and 250 controls were included. Research information was obtained from their medical records. Blood samples were collected on admission. Serum concentration of programmed cell death ligand 1 was measured using Enzyme-Linked Immunosorbent Assay. The patients underwent cisplatin-etoposide chemotherapy with a maximum of six cycles. Subsequently, they were followed-up for 12 months, and therapeutic response and cancer death were recorded. RESULTS: Serum concentration of programmed cell death ligand 1 was higher in the patients than in the controls on admission (P < 0.001). After chemotherapy, 112 patients had no response to this therapy. In the 12-month follow up period, 118 patients died due to this cancer. Multivariate Cox regression model revealed that the higher serum concentration of programmed cell death ligand 1 on admission was associated with the higher risk of no response to chemotherapy or cancer caused death (HR: 1.40, 95% CI: 1.05 ~ 1.87; HR: 1.43, 95% CI: 1.08 ~ 1.87). CONCLUSION: Elevated serum concentration of soluble programmed cell death ligand 1 might be an independent risk factor for non-response to chemotherapy and cancer caused death in small cell lung cancer patients.


Assuntos
Antígeno B7-H1/metabolismo , Biomarcadores Tumorais/sangue , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/diagnóstico , Carcinoma de Pequenas Células do Pulmão/sangue , Carcinoma de Pequenas Células do Pulmão/diagnóstico , Idoso , Antineoplásicos/uso terapêutico , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias/métodos , Prognóstico , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico
7.
J Sep Sci ; 40(24): 4813-4824, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29045059

RESUMO

Cylindrical and parallel-plate electrophoretic separations for the removal of ions and sub-23 nm particles were compared in this study. First, COMSOL Multiphysics® software was utilized to simulate the ion and particle trajectories inside both electrophoretic separations. The results show that ions and sub-23 nm particles are removed simultaneously and that all particles can pass through both electrophoretic separations smoothly at a trap voltage of 25 V. The experimental results show that ion losses become smaller with increasing ion flow rates, and ion losses of the cylindrical and parallel-plate electrophoretic separations range from 56.2 to 71.6% and from 43.8 to 59.6%, respectively, at ion flow rates ranging from 1-3 L/min. For the removal of ions and sub-23 nm particles, the collection efficiency of both electrophoretic separations can reach 100%, but the parallel-plate electrophoretic separation requires a lower trap voltage. The particle loss of the parallel-plate electrophoretic separation is under approximately 10%, which is lower than that of the cylindrical electrophoretic separation. In particular, for large particles (800-2500 nm), the particle losses inside the cylindrical electrophoretic separation are approximately two times higher than those inside the parallel-plate electrophoretic separation. The parallel-plate electrophoretic separation is beneficial for the removal of ions and sub-23 nm particles.

8.
Sensors (Basel) ; 16(8)2016 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-27472342

RESUMO

In this paper, a novel velocimeter based on laser self-mixing Doppler technology has been developed for speed measurement. The laser employed in our experiment is a distributed feedback (DFB) fiber laser, which is an all-fiber structure using only one Fiber Bragg Grating to realize optical feedback and wavelength selection. Self-mixing interference for optical velocity sensing is experimentally investigated in this novel system, and the experimental results show that the Doppler frequency is linearly proportional to the velocity of a moving target, which agrees with the theoretical analysis commendably. In our experimental system, the velocity measurement can be achieved in the range of 3.58 mm/s-2216 mm/s with a relative error under one percent, demonstrating that our novel all-fiber configuration velocimeter can implement wide-range velocity measurements with high accuracy.

9.
J Biochem Mol Toxicol ; 28(1): 39-45, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24395429

RESUMO

Arctigenin, a dibenzylbutyrolactone lignan, enhances cisplatin-mediated cell apoptosis in cancer cells. Here, we sought to investigate the effects of arctigenin on cisplatin-treated non-small-cell lung cancer (NSCLC) H460 cells. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and annexin-V/propidium iodide staining were performed to analyze the proliferation and apoptosis of H460 cells. Arctigenin dose-dependently suppressed cell proliferation and potentiated cell apoptosis, coupled with increased cleavage of caspase-3 and poly(ADP-ribose) polymerase. Moreover, arctigenin sensitized H460 cells to cisplatin-induced proliferation inhibition and apoptosis. Arctigenin alone or in combination with cisplatin had a significantly lower amount of survivin. Ectopic expression of survivin decreased cell apoptosis induced by arctigenin (P < 0.05) or in combination with cisplatin (P < 0.01). Moreover, arctigenin (P < 0.05) or in combination with cisplatin (P < 0.01) induced G1/G0 cell-cycle arrest. Our data provide evidence that arctigenin has a therapeutic potential in combina-tion with chemotherapeutic agents for NSLC.


Assuntos
Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Cisplatino/farmacologia , Regulação para Baixo/efeitos dos fármacos , Furanos/farmacologia , Proteínas Inibidoras de Apoptose/metabolismo , Lignanas/farmacologia , Neoplasias Pulmonares/patologia , Sequência de Bases , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Ciclo Celular , Linhagem Celular Tumoral , Primers do DNA , Resistencia a Medicamentos Antineoplásicos , Sinergismo Farmacológico , Humanos , Neoplasias Pulmonares/metabolismo , Reação em Cadeia da Polimerase , Survivina
10.
Arch Virol ; 158(5): 1013-9, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23250650

RESUMO

A replication-defective, recombinant Sindbis virus vector was utilized in a novel immunization strategy to induce humoral and cellular responses against hepatitis C virus (HCV). The recombinant vector, pVaXJ-E1E2, expressing the gene for HCV glycoproteins E2 and E1, was constructed by inserting the E1E2 gene into the replicon pVaXJ, a DNA vector derived from Sindbis-like virus XJ-160. The defective replicon particles, XJ-E1E2, were produced by transfecting BHK-21(E+Capsid) cells, the packaging cell lines for the vector from XJ-160 virus, with pVaXJ-E1E2. Both glycoproteins, E2 and E1, were stably expressed, as indicated by immunofluorescence assay (IFA) and Western blotting. Mice were vaccinated using a prime-boost strategy with XJ-E1E2 particles combined with Freund's incomplete adjuvant via intramuscular injection at 0 and 2 weeks. HCV-specific IgG antibody levels and cellular immune responses were evaluated by IFA and IFN-γ ELISPOT, respectively. The results showed that the defective XJ-E1E2 particles in combination with Freund's incomplete adjuvant induced effective humoral and cellular immune responses against HCV glycoprotein E1 or E2, suggesting that a defective Sindbis particle vaccine is capable of eliciting an effective immune response. These findings have important implications for the development of HCV vaccine candidates.


Assuntos
Portadores de Fármacos , Vetores Genéticos , Hepacivirus/imunologia , Sindbis virus/genética , Proteínas do Envelope Viral/imunologia , Vacinas Virais/imunologia , Animais , Feminino , Adjuvante de Freund/administração & dosagem , Hepacivirus/genética , Anticorpos Anti-Hepatite C/sangue , Imunidade Celular , Imunoglobulina G/sangue , Injeções Intramusculares , Leucócitos Mononucleares/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Vacinação/métodos , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia , Proteínas do Envelope Viral/genética , Vacinas Virais/administração & dosagem , Vacinas Virais/genética
11.
J Virol ; 85(19): 9847-53, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21697481

RESUMO

Japanese encephalitis virus (JEV), a mosquito-borne zoonotic pathogen, is one of the major causes of viral encephalitis worldwide. Previous phylogenetic studies based on the envelope protein indicated that there are four genotypes, and surveillance data suggest that genotype I is gradually replacing genotype III as the dominant strain. Here we report an evolutionary analysis based on 98 full-length genome sequences of JEV, including 67 new samples isolated from humans, pigs, mosquitoes, midges. and bats in affected areas. To investigate the relationships between the genotypes and the significance of genotype I in recent epidemics, we estimated evolutionary rates, ages of common ancestors, and population demographics. Our results indicate that the genotypes diverged in the order IV, III, II, and I and that the genetic diversity of genotype III has decreased rapidly while that of genotype I has increased gradually, consistent with its emergence as the dominant genotype.


Assuntos
Vírus da Encefalite Japonesa (Espécie)/classificação , Vírus da Encefalite Japonesa (Espécie)/genética , Encefalite Japonesa/epidemiologia , Encefalite Japonesa/virologia , Genoma Viral , Animais , Ásia/epidemiologia , Análise por Conglomerados , Vírus da Encefalite Japonesa (Espécie)/isolamento & purificação , Genótipo , Humanos , Dados de Sequência Molecular , Filogenia , RNA Viral/genética , Análise de Sequência de DNA
12.
Environ Sci Pollut Res Int ; 29(47): 72033-72044, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35608762

RESUMO

The micro and nano bubble (MNB) technology, due to its promising features and advantages, has become increasingly popular in agriculture. MNB-treated water positively impacts plant growth, especially when it is treated with a combination of gas-like carbon dioxide (CO2), injected through the MNB generator. Therefore, this study used MNB water with CO2 that are small bubbles of nanometer and micrometer diameters having several unique physical properties that make them useful for water treatments. This research evaluates the effect of MNBs and CO2-treated water on leafy vegetable Amaranth green (Amaranthus viridis). The experiment divided the Amaranth plants into three major groups, G1, G2, and G3, irrigated by MNB water with dissolved CO2, MNBs with only Air, and simple tap water, respectively. The first treatment group (G1) (MNBs with CO2) was further divided into three sub-divisions, i.e., G1A, G1B, G1C, and the second treatment group G2 (MNBs with Air) was divided into three sub-groups, i.e., G2A, G2B, and G2C, while the third group G3 with only one category as only controlled group. These sub-divisions of treatment groups G1 and G2 were done to investigate the impact of MNBs and CO2 treated water with different time durations. For example, in G1A, the water treatment with MNBs and CO2 was kept five minutes, for G1B 10 minutes, and G1C 15 minutes. Similar method was adopted for G2 as well. According to the results, water treated with MNB and CO2 has a significant (90%) impact on the Amaranth germination rate and plant growth. Specifically, pots irrigated with the MNBs + CO2-treated water showed better germination and plant growth rate than the MNBs + Air treated water. Overall, both treatment groups, G1 and G2, showed significantly higher impacts than the CK groups (simple water). Further, this experiment showed that the 10 and 15 minutes treatment of water (G1B, G1C and G2B, G2C) increased the stem height and root size compared to the 5 minutes treated water (G1A, G2A). This study concludes that the water with MNBs has a positive impact on the vegetables and can be an effective technology to improve crop yield.


Assuntos
Amaranthus , Fenômenos Biológicos , Agricultura , Benzenossulfonatos , Dióxido de Carbono
13.
Transl Cancer Res ; 11(9): 3337-3342, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36237231

RESUMO

Background: Approximately 10-25% of patients with small cell lung cancer (SCLC) have brain metastases at the time of diagnosis. Radiotherapy is a common treatment for brain metastases, but the relapse rates are high. Accumulating evidence suggests that immunotherapy may have a better therapeutic effect for brain metastases. Here, we reported a patient with limited-stage SCLC and relapsed brain metastases who achieved sustained intracranial complete response (CR) to programmed cell death-1 (PD-1) inhibitor toripalimab and multikinase inhibitor anlotinib. Case Description: A 59-year-old female patient developed brain metastases after initial treatment for limited stage SCLC. CR of brain lesions was achieved after intensity-modulated radiation therapy followed by chemotherapy with irinotecan plus lobaplatin and concurrent anlotinib. PD-1 inhibitor sintilimab combined with anlotinib were given as maintenance therapy. Small and asymptomatic brain lesions relapsed 2.5 months after achieving CR. Another three cycles of sintilimab combined with anlotinib failed to control the relapsed brain lesions. Following two cycles of another PD-1 inhibitor toripalimab combined with anlotinib, the relapsed brain metastases disappeared. Then the patient received another seven cycles of this regimen with sustained CR, and no serious adverse reactions occurred. Interestingly, the primary lung tumor achieved sustained CR from the end of initial treatment to the last follow-up. Conclusions: This case suggests that toripalimab in combination with anlotinib may be a promising treatment option for patients with brain metastases from SCLC.

14.
Virol J ; 8: 344, 2011 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-21740598

RESUMO

To investigate the necessity and potential application of structural genes for expressing heterogenous genes from Sindbis virus-derived vector, the DNA-based expression vector pVaXJ was constructed by placing the recombinant genome of sindbis-like virus XJ-160 under the control of the human cytomegalovirus (CMV) promoter of the plasmid pVAX1, in which viral structural genes were replaced by a polylinker cassette to allow for insertion of heterologous genes. The defect helper plasmids pVaE or pVaC were developed by cloning the gene of glycoprotein E3E26KE1 or capsid protein of XJ-160 virus into pVAX1, respectively. The report gene cassette pVaXJ-EGFP or pV-Gluc expressing enhanced green fluorescence protein (EGFP) or Gaussia luciferase (G.luc) were constructed by cloning EGFP or G.luc gene into pVaXJ. EGFP or G.luc was expressed in the BHK-21 cells co-transfected with report gene cassettes and pVaE at levels that were comparable to those produced by report gene cassettes, pVaC and pVaE and were much higher than the levels produced by report gene cassette and pVaC, suggesting that glycoprotein is enough for Sindbis virus-derived DNA vector to express heterogenous genes in host cells. The method of gene expression from Sindbis virus-based DNA vector only co-transfected with envelop E gene increase the conveniency and the utility of alphavirus-based vector systems in general.


Assuntos
Engenharia Genética/métodos , Vetores Genéticos , Glicoproteínas/metabolismo , Sindbis virus/crescimento & desenvolvimento , Sindbis virus/genética , Proteínas Virais/metabolismo , Genes Reporter , Glicoproteínas/genética , Humanos , Regiões Promotoras Genéticas , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas Virais/genética
15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(1): 12-5, 2011 Jan.
Artigo em Zh | MEDLINE | ID: mdl-21428045

RESUMO

FAIMS is a fast and high sensitive technique for detecting trace volatile organic compounds. Spectra of acetone, benzene and toluene were obtained on a homemade high-field asymmetric waveform ion mobility spectrometer and they can be easily separated in the spectra. Three xylene isomeric compounds were also successfully separated in FAIMS. Effect of carrier gas flow rate on the ion intensity was analyzed, and the optimal flow rate of carrier gas was 220 L x h(-1) which can be used for the optimization of FAIMS instrument. The detection limit for acetone is 100 ng x L(-1) that is an order of magnitude lower than the foreign traditional IMS.

16.
Sci China Life Sci ; 64(9): 1522-1532, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33452997

RESUMO

Intracellular polyamines (putrescine, spermidine, and spermine) have emerged as important molecules for viral infection; however, how viruses activate polyamines biosynthesis to promote viral infection remains unclear. Ornithine decarboxylase 1 (ODC1) and its antienzyme 1 (OAZ1) are major regulators of polyamine biosynthesis in animal cells. Here, we report that rice yellow stunt virus (RYSV), a plant rhabdovirus, could activate putrescine biosynthesis in leafhoppers to promote viral propagation by inhibiting OAZ1 expression. We observed that the reduction of putrescine biosynthesis by treatment with difluormethylornithine (DFMO), a specific nontoxic inhibitor of ODC1, or with in vitro synthesized dsRNAs targeting ODC1 mRNA could inhibit viral infection. In contrast, the supplement of putrescine or the increase of putrescine biosynthesis by treatment with dsRNAs targeting OAZ1 mRNA could facilitate viral infection. We further determined that both RYSV matrix protein M and ODC1 directly bind to the ODC-binding domain at the C-terminus of OAZ1. Thus, viral propagation in leafhoppers would decrease the ability of OAZ1 to target and mediate the degradation of ODC1, which finally activates putrescine production to benefit viral propagation. This work reveals that polyamine-metabolizing enzymes are directly exploited by a vector-borne virus to increase polyamine production, thereby facilitating viral infection in insect vectors.


Assuntos
Gafanhotos/virologia , Insetos Vetores/virologia , Inibidores da Ornitina Descarboxilase/farmacologia , Oryza/enzimologia , Oryza/virologia , Vírus de Plantas/crescimento & desenvolvimento , Poliaminas/metabolismo , Animais
17.
J Gen Virol ; 91(Pt 11): 2836-45, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20702653

RESUMO

During an investigation of arboviruses in China, a novel dsRNA virus was isolated from adult female Armigeres subalbatus. Full genome sequence analysis showed the virus to be related to members of the family Totiviridae, and was therefore named 'Armigeres subalbatus totivirus' (AsTV). Transmission electron microscopy identified icosahedral, non-enveloped virus particles with a mean diameter of 40 nm. The AsTV genome is 7510 bp in length, with two ORFs. ORF1 (4443 nt) encodes the coat-protein and a dsRNA-binding domain (which may be involved in the evasion of 'gene silencing'), while ORF2 (2286 nt) encodes the viral RNA-dependent RNA polymerase (RdRp). The AsTV coat protein shows a higher level of amino acid identity with Drosophila totivirus (DTV, 52 %) than with infectious myonecrosis virus (IMNV, 29 %). Similarly, the RdRp shows higher identity levels with DTV (51 %) than with IMNV (44 %). Identity levels to other members of the family Totiviridae, in either the coat protein or the RdRp, ranged from 6 to 11 %. Based on a recent reassessment of the coding strategy used by IMNV, we suggest that an AsTV coat-RdRp fusion protein could be synthesized via a -1 frameshift. Elements favouring -1 frameshift such as 'slippery heptamers' and pseudonkots, were identified in the AsTV, DTV and IMNV genomes. AsTV was shown to grow in both mosquito and mammalian cells, suggesting that it is an arbovirus that can infect mammals.


Assuntos
Culicidae/virologia , Genoma Viral , RNA Viral/genética , Totivirus/genética , Totivirus/isolamento & purificação , Sequência de Aminoácidos , Animais , Sequência de Bases , Proteínas do Capsídeo/genética , China , Análise por Conglomerados , Mudança da Fase de Leitura do Gene Ribossômico , Mamíferos , Microscopia Eletrônica de Transmissão , Modelos Moleculares , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Fases de Leitura Aberta , Filogenia , Biossíntese de Proteínas , RNA de Cadeia Dupla/genética , RNA Polimerase Dependente de RNA/genética , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Totivirus/ultraestrutura , Proteínas Virais/genética , Vírion/ultraestrutura
18.
Zhonghua Jie He He Hu Xi Za Zhi ; 33(6): 427-31, 2010 Jun.
Artigo em Zh | MEDLINE | ID: mdl-20979814

RESUMO

OBJECTIVE: To investigate the expression and role of O(6)-methylguanine DNA methyltransferase (MGMT) and p53 in non-small cell lung cancer (NSCLC) and the association with prognosis. METHODS: Immunohistochemical method was used to investigate the expression of MGMT and p53 in NSCLC specimens from 110 cases and in 20 cases of benign lung diseases as the control. The association of their expression with the prognosis of the 110 patients was evaluated. RESULTS: The positive expression of MGMT in NSCLC and benign lung diseases was 41.8% (46/110) and 80% (16/20) (χ(2) = 9.89, P < 0.05), respectively. The positive expression of p53 in NSCLC and benign lung diseases were 56.4% (62/110) and 0% (0/20) (χ(2) = 21.551, P < 0.05), respectively. There was a significant association between expression of MGMT with smoking, and lymph node metastasis (χ(2) = 12.107, P < 0.05; χ(2) = 6.512P < 0.05). There was also a significant association between expression of p53 with smoking and lymph node metastasis (χ(2) = 6.330, P < 0.05; χ(2) = 7.909, P < 0.05). A negative correlation was observed between the expression of MGMT and that of p53 protein in NSCLC (R(S) = -0.592, P < 0.05). The 5-year survival rate and median survival time of 110 cases was 10.9% (12/110), and (30.4 ± 0.6) months. In 46 cases with positive expression of MGMT the 5-year survival rate was 0% (0/110) and median survival was (25.9 ± 0.4) months, which were lower than those in the 64 patients with negative expression of MGMT [18.8% (12/64), (32.4 ± 0.7) months], Log rank test χ(2) = 23.569, P < 0.05. In the 62 patients with positive expression of p53, the 5-year survival rate and median survival were 4.8% (3/62) and (30.4 ± 1.2) months, which were lower than those in the 48 cases with negative expression of p53 [18.8% (9/48), (30.5 ± 1.1) months], Log rank test χ(2) = 5.521, P < 0.05. CONCLUSION: The loss of expression of MGMT may lead to activation of the wild-type p53. They may participate in lung carcinomatosis, and may predict prognosis in patients with NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/genética , O(6)-Metilguanina-DNA Metiltransferase/genética , Proteína Supressora de Tumor p53/genética , Idoso , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Feminino , Regulação Neoplásica da Expressão Gênica , Genes p53 , Humanos , Neoplasias Pulmonares/diagnóstico , Masculino , Pessoa de Meia-Idade , Mutação , Prognóstico
19.
Zhonghua Yu Fang Yi Xue Za Zhi ; 43(5): 385-9, 2009 May.
Artigo em Zh | MEDLINE | ID: mdl-19534991

RESUMO

OBJECTIVE: To probe the primary characteristic of 0507JS11 virus isolated from Culex sp. and determine the classification of 0507JS11 virus in taxonomy. METHODS: 0507JS11 virus was cultured in Aedes albopictus C6/36 cells and cytopathic effects (CPEs) were recorded. Electro-microscopic morphology of 0507JS11 virus was observed. Total DNA extract of 0507JS11 virus was detected by 1% Agarose Gel Electrophoresis. Complete genomic sequence of 0507JS11 virus was sequenced and then made phylogenetic analysis. RESULTS: 0507JS11 virus could cause CPEs in Aedes albopictus C6/36 cells. Viral particles have no envelope and appear icosahedron symmetry with diameter of 20 nm. The genome of 0507JS11 virus was positive single strand DNA (ssDNA) with full length of 3977 nt. However, a DNA band about 4 kbp was observed in the electrophoresis of total DNA extract of 0507JS11 virus. The coding region of the genome included three ORFs, ORF1 and ORF2 code NSP1 and NSP2, ORF3 codes VP. Phylogenetic analysis of the complete genomic sequence of 0507JS11 virus indicated an independent linear in Brevidensovirus. CONCLUSION: 0507JS11 virus is a new member in Brevidensovirus.


Assuntos
Culex/virologia , Densovirinae/classificação , Densovirinae/isolamento & purificação , Animais , DNA Viral/genética , Densovirinae/genética , Genoma Viral , Análise de Sequência de DNA
20.
Zhonghua Yu Fang Yi Xue Za Zhi ; 43(5): 395-8, 2009 May.
Artigo em Zh | MEDLINE | ID: mdl-19534993

RESUMO

OBJECTIVE: To isolate viruses from mosquitoes in the south of Xinjiang and identify these viruses primarily. METHODS: A total of 13 491 mosquitoes were collected in the south of Xinjiang from Jul to Aug, 2005. These mosquitoes were divided into 130 groups and grinded respectively. The supernates were inoculated in C6/36 and Vero cells. Viruses isolated were detected, the genomic nucleic types by electrophoresis of viral genomes and the morphologies observed under electronmicroscope. RESULTS: All 42 viruses were isolated, which caused CPEs on C6/36 but not on Vero cells. 27 viruses showed similar genomic profiles with 12 dsRNA segments. 1 virus displayed genomic profile with 10 dsRNA segments. 5 viruses took on similar genomic profiles with about 4 kbp DNA band. 9 viruses did not get any taxonomy information. Electromicroscopic pictures of these viruses revealed that above four types of viruses had distinguished morphologies indicating different virus species. CONCLUSION: There should be several virus species in the mosquitoes in the south of Xinjiang. dsRNA virus with 12 genomic segments should play analysis a predominant role in the south of Xinjiang.


Assuntos
Culicidae/virologia , Genoma Viral , Vírus de Insetos/isolamento & purificação , Animais , Vírus Bluetongue/classificação , Vírus Bluetongue/genética , Vírus Bluetongue/isolamento & purificação , China , Chlorocebus aethiops , Vírus da Dengue/classificação , Vírus da Dengue/genética , Vírus da Dengue/isolamento & purificação , Vírus de Insetos/classificação , Vírus de Insetos/genética , RNA de Cadeia Dupla/genética , RNA Viral/genética , Vírus Reordenados/genética , Análise de Sequência de DNA , Células Vero
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