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1.
Nutrition ; 126: 112485, 2024 May 03.
Article de Anglais | MEDLINE | ID: mdl-39096779

RÉSUMÉ

OBJECTIVES: The combined impact of sleep quality and diet habits on ischemic stroke remains unclear, particularly in rural populations. Therefore, this study aimed to estimate the individual and joint associations of sleep quality and diet habits with nonfatal ischemic stroke among rural adults. METHODS: A total of 22 536 participants free of stroke were enrolled from the Henan Rural Cohort. Sleep quality and diet habits were evaluated with the Pittsburgh Sleep Quality Index and food frequency questionnaire, respectively. The ischemic stroke incidence was analyzed using Kaplan-Meier curves. Cox regression and restricted cubic spline were employed to estimate the correlation of sleep quality or diet habits with ischemic stroke. RESULTS: During an average 3.92 y of follow-up, 665 ischemic stroke patients were identified. The adjusted hazard ratio (95% confidence interval) of ischemic stroke risk compared with good sleep quality was 1.276 (1.057-1.542). The hazard ratio (95% confidence interval) of nonfatal ischemic stroke compared with unhealthy diet habits was 0.693 (0.589-0.814). The restricted cubic spline indicated that the risk of ischemic stroke increased with the increase of the Pittsburgh Sleep Quality Index. And the higher the diet quality score, the lower the risk of ischemic stroke. (Ptrend < 0.05). Further analysis indicated that the association of poor sleep quality with ischemic stroke was alleviated by healthy diet habits (P < 0.05). Additionally, a robust correlation remained after excluding individuals with ischemic stroke in the first year. CONCLUSIONS: Poor sleep quality was positively associated with nonfatal ischemic stroke among rural adults, and healthy diet habits attenuated this relationship. Developing healthy diet and sleep habits may have potential health implications for preventing ischemic stroke. TRIAL REGISTRATION: The Henan Rural Cohort Study has been registered at the Chinese Clinical Trial Register (registration no. ChiCTR-OOC-15006699). Date of registration: July 6, 2015.

2.
Materials (Basel) ; 17(7)2024 Apr 03.
Article de Anglais | MEDLINE | ID: mdl-38612154

RÉSUMÉ

Controlling infrared thermal radiations can significantly improve the environmental adaptability of targets and has attracted increasing attention in the field of thermal camouflage. Thermal emitters based on Ge2Sb2Te5 (GST) can flexibly change their radiation energy by controlling the reversible phase transition of GST, which possesses fast switching speed and low power consumption. However, the feasibility of the dynamic regulation of GST emitters lacks experimental and simulation verification. In this paper, we propose an electrically tunable thermal emitter consisting of a metal-insulator-metal plasmonic metasurface based on GST. Both optical and thermal simulations are conducted to optimize the structural parameters of the GST emitter. The results indicate that this emitter possesses large emissivity tunability, wide incident angle, polarization insensitivity, phase-transition feasibility, and dynamic thermal camouflage capability. Therefore, this work proposes a reliable optimization method to design viable GST-based thermal emitters. Moreover, it provides theoretical support for the practical application of phase-change materials in dynamic infrared thermal camouflage technology.

3.
Appl Opt ; 62(17): 4505-4511, 2023 Jun 10.
Article de Anglais | MEDLINE | ID: mdl-37707143

RÉSUMÉ

A high-energy and high-average-power pulsed fiber laser has been investigated in a master oscillator power amplifier (MOPA) configuration seeding with a diode laser at a programmed pulse duration of ∼250ns. The fiber amplifier successfully demonstrates the pulse with 21.4 mJ at the repetition rate of 50 kHz and a maximum average output power of 1535 W with a slope efficiency of 81.6% at 250 kHz. To overcome fiber nonlinearities such as stimulated Raman scattering (SRS) and self-phase modulation (SPM), extra-large mode area ytterbium (Yb)-doped step-index dual cladding fiber has been utilized as gain fiber in the MOPA laser system. The gain saturation effect in the power amplifier was greatly mitigated by the programmed seed signal. This pulse-shaped MOPA system can provide practical applications in many fields such as laser cleaning, paint stripping, and other applications requiring special pulse shapes.

4.
Eur J Nutr ; 62(7): 2929-2938, 2023 Oct.
Article de Anglais | MEDLINE | ID: mdl-37405440

RÉSUMÉ

PURPOSE: Insufficient evidence currently exists regarding the relationship between eating frequency and arteriosclerotic cardiovascular disease (ASCVD). Thus, the objective of this study was to explore the association of at-home eating (AHE) and out-of-home eating (OHE) frequency with 10-year ASCVD risk. METHODS: A total of 23,014 participants were included from the Henan Rural Cohort Study. A face-to-face questionnaire was used to acquire data on the frequency of OHE and AHE. The relationship of OHE and AHE frequency with 10-year ASCVD risk was evaluated by logistic regression. Mediation analysis was conducted to evaluate whether BMI mediated the association of OHE and AHE frequency with 10-year ASCVD risk. RESULTS: The adjusted OR and 95% CI of 10-year ASCVD risk for participants who ate out 7 or more times a week was 2.012 (1.666, 2.429) compared with participants who had OHE 0 times. Compared to those who had AHE ≤ 11 times, the adjusted OR and 95% CI for the participants eating every meal at home (21 times) was 0.611 (0.486, 0.769). The relationship of OHE and AHE frequency with 10-year ASCVD risk was mediated by BMI, and the proportion of BMI explained was 25.3% and 36.6%. CONCLUSIONS: The OHE frequency was associated with increased 10-year ASCVD risk, while AHE was related to decreased 10-year ASCVD risk, and BMI may play a partial mediating role in the relationship. Implementing health promotion strategies that promote AHE and discourage frequent OHE may prove to be an effective approach to preventing and controlling ASCVD. TRIAL REGISTRATION NUMBER: ChiCTR-OOC-15006699 (2015-07-06).


Sujet(s)
Maladies cardiovasculaires , Humains , Études de cohortes , Maladies cardiovasculaires/épidémiologie , Maladies cardiovasculaires/prévention et contrôle , Population rurale , Promotion de la santé , Repas , Facteurs de risque
5.
Spectrochim Acta A Mol Biomol Spectrosc ; 281: 121596, 2022 Nov 15.
Article de Anglais | MEDLINE | ID: mdl-35810671

RÉSUMÉ

In order to prevent the illegal discharge of oilfield wastewater, this work proposed excitation-emission matrix fluorescence (EEMF) spectroscopy coupled with two kinds of chemical pattern recognition methods for tracing the sources of oilfield wastewater. The first pattern recognition method was built from the relative concentrations extracted by alternating trilinear decomposition (ATLD) based on partial least squares-discriminant analysis (PLS-DA) algorithm, and the other one was modeled based on strictly multi-way partial least squares-discriminant analysis (N-PLS-DA). Both methods showed good discrimination abilities for oilfield wastewater samples from three different sources. The total recognition rates of the training and prediction sets are 100%, the values of sensitivity and selectivity are 1. This study showed that EEMF spectroscopy combined with chemical pattern recognition techniques could be used as a potential tool for tracing the sources of oilfield wastewater.


Sujet(s)
Champs de pétrole et de gaz , Eaux usées , Analyse discriminante , Méthode des moindres carrés , Spectrométrie de fluorescence/méthodes
6.
Entropy (Basel) ; 24(6)2022 May 25.
Article de Anglais | MEDLINE | ID: mdl-35741471

RÉSUMÉ

The issue of monitoring and early warning of rock instability has received increasing critical attention in the study of rock engineering. To investigate the damage evolution process of granite under triaxial compression tests, acoustic emission (AE) tests were performed simultaneously. This study firstly introduced two novel parameters, i.e., the coefficient of variation (CoV) of the information entropy and correlation dimension of the amplitude data from the AE tests, to identify the precursor of the failure of granite. Then the relationship between the changes in these parameters and the stress-time curve was compared and analyzed. The results of this study show that: (1) There is a strong correlation between the CoV of the information entropy and the failure process of granite. The granite failed when the CoV curve raised to a plateau, which could be used as an indicator of rock instability. (2) The fluctuation of the correlation dimension indicates the different stages during the loading process, i.e., the initial compaction stage, the linear elastic stage, the yield stage, and the failure stage. Each stage contains a descending and a rising process in the correlation dimension curve, and the exhibited starting point or the bottom point at the correlation dimension curve could be selected as the indicator point for the rock instability. (3) The combined analysis of the Information entropy and Correlation dimension can improve the accuracy of rock instability prediction. This study provides new insights into the prediction of rock instability, which has theoretical implications for the stability of subsurface engineering rock masses.

7.
Appl Opt ; 59(22): 6443-6451, 2020 Aug 01.
Article de Anglais | MEDLINE | ID: mdl-32749341

RÉSUMÉ

A hybrid model based on a wavelet threshold de-noising (WTD) and recursive feature elimination with cross-validation (RFECV) method was proposed to improve the measurements in quantitative analysis of coal properties using laser-induced breakdown spectroscopy (LIBS). First, a modified threshold of WTD was proposed based on wavelet coefficient theory. Interference of noise in the LIBS spectrum was reduced by using this modified method. Then, the RFECV method was applied to extract effective features from the de-noised LIBS spectrum. Finally, support vector regression (SVR) models of coal properties were established by the selected features. A validation set was used to verify the effectiveness and robustness of the hybrid model. The improvement of the hybrid model on the quantitative analysis of each index of coal properties (heat value, ash, volatile content) was studied and discussed. By using the proposed model, the determination coefficient (R2), root mean square error of prediction, average relative error, and relative standard deviation were all significantly improved over the original spectra model. The results demonstrated that the proposed model could effectively improve the accuracy and precision of LIBS quantitative analysis for coal properties.

8.
Appl Opt ; 58(13): 3459-3466, 2019 May 01.
Article de Anglais | MEDLINE | ID: mdl-31044843

RÉSUMÉ

By using a kind of simple Michelson-type lateral shearing interferometry, in this paper, the precise quantitative phase measurement of transparent microscopic objects is realized successfully. For this interferometry, on the basis of the fundamental structure of the traditional Michelson interferometer, the two plane mirrors are replaced with two ordinary right-angle prisms. In the beginning, the ridges of the two right-angle prisms are set to align with the optical axis and be in the vertical direction. Subsequently, to achieve the lateral shear, one of these two right-angle prisms is rotated around its ridge. Furthermore, the goal to obtain more lateral shear can be achieved by introducing a bigger rotating angle or rotating another prism simultaneously. In addition, owing to the simple structure of the Michelson interferometer and the inexpensive optical components used, the system is compact, portable, easy to operate, and low cost. The experimental results show the practicability of this system.

9.
BMC Biotechnol ; 19(1): 23, 2019 04 24.
Article de Anglais | MEDLINE | ID: mdl-31014302

RÉSUMÉ

BACKGROUND: The gene transduction efficiency of adenovirus to hematopoietic cells, especially T lymphocytes, is needed to be improved. The purpose of this study is to improve the transduction efficiency of T lymphocytes by using fiber-modified human adenovirus 5 (HAdV-5) vectors. RESULTS: Four fiber-modified human adenovirus 5 (HAdV-5) vectors were investigated to transduce hematopoietic cells. F35-EG or F11p-EG were HAdV-35 or HAdV-11p fiber pseudotyped HAdV-5, and HR-EG or CR-EG vectors were generated by incorporating RGD motif to the HI loop or to the C-terminus of F11p-EG fiber. All vectors could transduce more than 90% of K562 or Jurkat cells at an multiplicity of infection (MOI) of 500 viral particle per cell (vp/cell). All vectors except HR-EG could transduce nearly 90% cord blood CD34+ cells or 80% primary human T cells at the MOI of 1000, and F11p-EG showed slight superiority to F35-EG and CR-EG. Adenoviral vectors transduced CD4+ T cells a little more efficiently than they did to CD8+ T cells. These vectors showed no cytotoxicity at an MOI as high as 1000 vp/cell because the infected and uninfected T cells retained the same CD4/CD8 ratio and cell growth rate. CONCLUSIONS: HAdV-11p fiber pseudotyped HAdV-5 could effectively transduce human T cells when human EF1a promoter was used to control the expression of transgene, suggesting its possible application in T cell immunocellular therapy.


Sujet(s)
Adénovirus humains/génétique , Techniques de transfert de gènes/normes , Vecteurs génétiques/génétique , Lymphocytes T/métabolisme , Protéines virales queue/génétique , Lymphocytes T CD4+/métabolisme , Lymphocytes T CD4+/virologie , Lymphocytes T CD8+/métabolisme , Lymphocytes T CD8+/virologie , Prolifération cellulaire/génétique , Thérapie génétique/méthodes , Cellules HL-60 , Humains , Cellules Jurkat , Cellules K562 , Lymphocytes T/virologie , Transduction génétique/normes , Transgènes/génétique , Cellules U937 , Protéines virales queue/métabolisme
10.
J Virol Methods ; 257: 85-92, 2018 07.
Article de Anglais | MEDLINE | ID: mdl-29703616

RÉSUMÉ

Plasmid bearing adenovirus genome is generally constructed with the method of homologous recombination in E. coli BJ5183 strain. Here, we utilized Gibson gene assembly technique to generate infectious clone of fowl adenovirus 4 (FAdV-4). Primers flanked with partial inverted terminal repeat (ITR) sequence of FAdV-4 were synthesized to amplify a plasmid backbone containing kanamycin-resistant gene and pBR322 origin (KAN-ORI). DNA assembly was carried out by combining the KAN-ORI fragment, virus genomic DNA and DNA assembly master mix. E. coli competent cells were transformed with the assembled product, and plasmids (pKFAV4) were extracted and confirmed to contain viral genome by restriction analysis and sequencing. Virus was successfully rescued from linear pKFAV4-transfected chicken LMH cells. This approach was further verified in cloning of human adenovirus 5 genome. Our results indicated that DNA assembly technique simplified the construction of infectious clone of adenovirus, suggesting its possible application in virus traditional or reverse genetics.


Sujet(s)
Aviadenovirus/croissance et développement , Aviadenovirus/génétique , ADN viral/génétique , Génétique inverse/méthodes , Animaux , Lignée cellulaire , Poulets , Escherichia coli/génétique , Plasmides , Recombinaison génétique , Transfection
11.
Appl Opt ; 56(3): 404-408, 2017 Jan 20.
Article de Anglais | MEDLINE | ID: mdl-28157885

RÉSUMÉ

An all-normal dispersion fiber laser mode-locked by nonlinear polarization evolution is presented in this paper. A magneto-optical polarization controller is employed in a fiber laser to optimize the polarization state and mode-locking operation. In order to provide an adjustable and large enough magnetic field for magneto-optical crystals, a magnetic yoke is designed with silicon steel and copper coil. The Q-switched and continuous-wave mode-locking regime of the fiber laser are investigated experimentally. At a pumping power of 2.08 W, the laser can generate stable mode-locking pulses with an average power of 213 mW. The repetition rate and the pulse duration are 63.7 MHz and 6.2 ps, respectively, corresponding to a pulse energy of 3.34 nJ and a peak power of 539 W. The laser can operate continuously in mode-locking states over five hours with almost no variation in pulse profile, optical spectrum, and output power.

12.
J Virol ; 91(6)2017 03 15.
Article de Anglais | MEDLINE | ID: mdl-28077642

RÉSUMÉ

Defensins are small antimicrobial peptides capable of neutralizing human adenovirus (HAdV) in vitro by binding capsid proteins and blocking endosomal escape of virus. In humans, the alpha defensin HD5 is produced by specialized epithelial cells of the gastrointestinal and genito-urinary tracts. Here, we demonstrate, using patient biopsy specimens, that HD5 is also expressed as an active, secreted peptide by epithelial ovarian and lung cancer cells in situ This finding prompted us to study the role of HD5 in infection and spread of replication-competent, oncolytic HAdV type 3 (HAdV3). HAdV3 produces large amounts of penton-dodecahedra (PtDd), virus-like particles, during replication. We have previously shown that PtDd are involved in opening epithelial junctions, thus facilitating lateral spread of de novo-produced virions. Here, we describe a second function of PtDd, namely, the blocking of HD5. A central tool to prove that viral PtDd neutralize HD5 and support spread of progeny virus was an HAdV3 mutant virus in which formation of PtDd was disabled (mut-Ad3GFP, where GFP is green fluorescent protein). We demonstrated that viral spread of mut-Ad3GFP was blocked by synthetic HD5 whereas that of the wild-type (wt) form (wt-Ad3GFP) was only minimally impacted. In human colon cancer Caco-2 cells, induction of cellular HD5 expression by fibroblast growth factor 9 (FGF9) significantly inhibited viral spread and progeny virus production of mut-Ad3GFP but not of wt-Ad3GFP. Finally, the ectopic expression of HD5 in tumor cells diminished the in vivo oncolytic activity of mut-Ad3GFP but not of wt-Ad3GFP. These data suggest a new mechanism of HAdV3 to overcome innate antiviral host responses. Our study has implications for oncolytic adenovirus therapy.IMPORTANCE Previously, it has been reported that human defensin HD5 inactivates specific human adenoviruses by binding to capsid proteins and blocking endosomal escape of virus. The central new findings described in our manuscript are the following: (i) the discovery of a new mechanism used by human adenovirus serotype 3 to overcome innate antiviral host responses that is based on the capacity of HAdV3 to produce subviral penton-dodecahedral particles that act as decoys for HD5, thus preventing the inactivation of virus progeny produced upon replication; (ii) the demonstration that ectopic HD5 expression in cancer cells decreases the oncolytic efficacy of a serotype 5-based adenovirus vector; and (iii) the demonstration that epithelial ovarian and lung cancers express HD5. The study improves our understanding of how adenoviruses establish infection in epithelial tissues and has implications for cancer therapy with oncolytic adenoviruses.


Sujet(s)
Adénovirus humains/immunologie , Cellules épithéliales/immunologie , Cellules épithéliales/virologie , Échappement immunitaire , Thérapie virale de cancers , Virus oncolytiques/immunologie , Défensines-alpha/métabolisme , Biopsie , Cellules Caco-2 , Femelle , Humains , Tumeurs du poumon/anatomopathologie , Tumeurs de l'ovaire/anatomopathologie
13.
Vaccine ; 34(46): 5579-5586, 2016 11 04.
Article de Anglais | MEDLINE | ID: mdl-27682509

RÉSUMÉ

Neutralizing antibody (NAb) can dampen the immunogenicity of adenovirus (Ad) vector-based vaccine. Vector systems based on human adenovirus type 41 (Ad41) have been constructed and used to develop recombinant vaccines. Here, we attempted to study the seroprevalence of NAbs to Ad5 and Ad41 among children and adults in Qinghai province, China. The positive rates (titer⩾40) of Ad5 and Ad41 NAb in adults from Xining city were 75.7% and 94.7%, respectively. The moderate/high-positive rates (titer⩾160) of NAb were quite close between the two viruses in adults (70.4% for Ad5 and 73.5% for Ad41). Age-dependent increase of NAb seroprevalence was observed for both viruses in children. NAb-positive rate of Ad41 reached 50% at 3.3-4.6years of age for children from Chengxi district, Xining city, approximately 1.5years earlier than that of Ad5 did. Interestingly, NAb level was also associated with sanitary conditions among young children. For Ad5, 8-15% children (0.2-3.0years of age) from city or town, where the sanitations were relatively better, had moderate/high-positive NAb, while the same rate was 62% for children from villages. For Ad41, 22% children from city, 47% from town and 88% from villages possessed moderate/high-positive NAb. The possible influence of NAb titer distributions on the application of Ad41-vectored vaccines was discussed in detail. Our results suggested that children from places with poor sanitations should be included for comprehensive Ad NAb seroprevalence studies, and provided insights to the applications of Ad41 vectors.


Sujet(s)
Infections à Adenoviridae/immunologie , Adénovirus humains/immunologie , Anticorps neutralisants/sang , Anticorps antiviraux/sang , Amélioration du niveau sanitaire , Infections à Adenoviridae/épidémiologie , Infections à Adenoviridae/virologie , Vaccins anti-adénovirus/immunologie , Adolescent , Adulte , Facteurs âges , Sujet âgé , Sujet âgé de 80 ans ou plus , Enfant , Enfant d'âge préscolaire , Chine/épidémiologie , Femelle , Vecteurs génétiques , Humains , Nourrisson , Nouveau-né , Mâle , Adulte d'âge moyen , Études séroépidémiologiques , Vaccins synthétiques/immunologie , Jeune adulte
14.
Appl Opt ; 55(21): 5766-70, 2016 Jul 20.
Article de Anglais | MEDLINE | ID: mdl-27463935

RÉSUMÉ

We propose a cross-splicing method, for the first time to our knowledge, to compensate the effect of fiber birefringence in a polarization-maintaining fiber ring laser mode locked by nonlinear polarization evolution. This method has been investigated numerically and experimentally. The results indicate that stable mode-locking pulses can be obtained in the cavity with this method; otherwise, no mode-locking states are achieved. The design processes of the laser cavity are presented. Pulses with single pulse energy of 2.1 nJ are generated at pump power of 460 mW. The spectral bandwidth and pulse duration are 17.5 nm and 11.7 ps, respectively. The tunability of the laser is also studied. The central wavelength can be tuned from 1023.2 to 1045.9 nm.

15.
Biomed Environ Sci ; 29(3): 224-8, 2016 Mar.
Article de Anglais | MEDLINE | ID: mdl-27109134

RÉSUMÉ

The nonstructural protein 1 (NS1) of influenza A virus, which is absent from the viral particle, but highly expressed in infected cells, strongly antagonizes the interferon (IFN)-mediated antiviral response. We engineered an NS1-expressing 293 (293-NS1) cell line with no response to IFN stimulation. Compared with the parental 293 cells, the IFN-nonresponsive 293-NS1 cells improved the growth capacity of various viruses, but the introduction of NS1 barely enhanced the propagation of Tahyna virus, a negative-strand RNA virus. In particular, fastidious enteric adenovirus that replicates poorly in 293 cells may grow more efficiently in 293-NS1 cells; thus, IFN-nonresponsive 293-NS1 cells might be of great value in diagnostic laboratories for the cultivation and isolation of human enteric adenoviruses.


Sujet(s)
Virus de la grippe A/physiologie , Protéines virales non structurales/métabolisme , Culture virale/méthodes , Réplication virale/physiologie , Lignée cellulaire , Régulation de l'expression des gènes , Cellules HEK293 , Humains , Protéines virales non structurales/génétique
16.
Hum Gene Ther ; 27(4): 325-37, 2016 Apr.
Article de Anglais | MEDLINE | ID: mdl-26993072

RÉSUMÉ

A central resistance mechanism in solid tumors is the maintenance of epithelial junctions between malignant cells that prevent drug penetration into the tumor. Human adenoviruses (Ads) have evolved mechanisms to breach epithelial barriers. For example, during Ad serotype 3 (Ad3) infection of epithelial tumor cells, massive amounts of subviral penton-dodecahedral particles (PtDd) are produced and released from infected cells to trigger the transient opening of epithelial junctions, thus facilitating lateral virus spread. We show here that an Ad3 mutant that is disabled for PtDd production is significantly less effective in killing of epithelial human xenograft tumors than the wild-type Ad3 virus. Intratumoral spread and therapeutic effect of the Ad3 mutant was enhanced by co-administration of a small recombinant protein (JO; produced in Escherichia coli) that incorporated the minimal junction opening domains of PtDd. We then demonstrated that co-administration of JO with replication-competent Ads that do not produce PtDd (Ad5, Ad35) resulted in greater attenuation of tumor growth than virus injection alone. Furthermore, we genetically modified a conditionally replicating Ad5-based oncolytic Ad (Ad5Δ24) to express a secreted form of JO upon replication in tumor cells. The JO-expressing virus had a significantly greater antitumor effect than the unmodified AdΔ24 version. Our findings indicate that epithelial junctions limit the efficacy of oncolytic Ads and that this problem can be address by co-injection or expression of JO. JO has also the potential for improving cancer therapy with other types of oncolytic viruses.


Sujet(s)
Adenoviridae/physiologie , Cellules épithéliales/métabolisme , Tumeurs/thérapie , Thérapie virale de cancers , Virus oncolytiques/physiologie , Protéines recombinantes/métabolisme , Animaux , Antinéoplasiques/pharmacologie , Lignée cellulaire tumorale , Desmogléine-2/métabolisme , Modèles animaux de maladie humaine , Cellules épithéliales/effets des médicaments et des substances chimiques , Protéines à fluorescence verte/métabolisme , Humains , Souris SCID , Mutation/génétique , Réplication virale/effets des médicaments et des substances chimiques
17.
Article de Anglais | WPRIM (Pacifique Occidental) | ID: wpr-258830

RÉSUMÉ

The nonstructural protein 1 (NS1) of influenza A virus, which is absent from the viral particle, but highly expressed in infected cells, strongly antagonizes the interferon (IFN)-mediated antiviral response. We engineered an NS1-expressing 293 (293-NS1) cell line with no response to IFN stimulation. Compared with the parental 293 cells, the IFN-nonresponsive 293-NS1 cells improved the growth capacity of various viruses, but the introduction of NS1 barely enhanced the propagation of Tahyna virus, a negative-strand RNA virus. In particular, fastidious enteric adenovirus that replicates poorly in 293 cells may grow more efficiently in 293-NS1 cells; thus, IFN-nonresponsive 293-NS1 cells might be of great value in diagnostic laboratories for the cultivation and isolation of human enteric adenoviruses.


Sujet(s)
Humains , Lignée cellulaire , Régulation de l'expression des gènes , Cellules HEK293 , Virus de la grippe A , Physiologie , Protéines virales non structurales , Génétique , Métabolisme , Culture virale , Méthodes , Réplication virale , Physiologie
18.
Virology ; 468-470: 388-396, 2014 Nov.
Article de Anglais | MEDLINE | ID: mdl-25240325

RÉSUMÉ

The human adenovirus (HAdV) early protein E1B55K interacts with E4orf6 to form an E3 ubiquitin ligase complex, which plays key roles in virus replication. To illustrate the reason for the fastidiousness of HAdV-41 in 293 cells, interaction between heterotypic E1B55K and E4orf6 proteins was investigated. HAdV-5 E1B55K could interact with HAdV-41 E4orf6, and vice versa. To form E1B55K/E4orf6 E3 ubiquitin ligase, HAdV-41 E4orf6 recruited Cul2 while HAdV-5 E4orf6 interacted with Cul5. The ligase complex formed by HAdV-5 E1B55K and HAdV-41 E4orf6 could cause the degradation of p53 and Mre11. However, in E1-deleted HAdV-41-infected 293TE7 cells, which expressed HAdV-41 E1B55K, viral late mRNAs were exported from nucleus more efficiently and accumulated to a higher concentration in cytoplasm when compared with that in infected 293 cells. These results suggested that interaction between homotypic E1B55K and E4orf6 was indispensable for efficient export of viral late mRNAs.


Sujet(s)
Adénovirus humains/physiologie , Régulation de l'expression des gènes viraux/physiologie , ARN messager/métabolisme , ARN viral/métabolisme , Cellules HEK293 , Humains , Mutation , Plasmides , ARN messager/génétique , ARN viral/génétique , Protéines virales/génétique , Protéines virales/métabolisme
19.
Bing Du Xue Bao ; 30(2): 154-61, 2014 Mar.
Article de Chinois | MEDLINE | ID: mdl-24923169

RÉSUMÉ

To investigate the morphogenetic process of human adenovirus type 41 (HAdV-41), 293TE cells were infected with purified wild-type HAdV-41, and ultrathin sections of infected cells were prepared and observed under a transmission electron microscope. Results showed that HAdV-41 entered host cells mainly through three ways: non-clathrin-coated pit, clathrin-coated pit, and direct penetration of plasma membrane. In addition, cell microvilli might help HAdV-41 enter cells. After entering into cells, HAdV-41 virus particles could be found in vacuoles or lysosomes or be in a free state in cytoplasm. Only free virus particles could be found near nuclear pores (NP), suggesting that the virus needed to escape from lysosomes for effective infection and viral nucleoprotein entered the nucleus through NP. Progeny viruses were as-sembled in the nucleus. Three types of inclusion bodies, which were termed as fibrillous inclusion body, condense inclusion body, and stripped condense inclusion body, were involved in HAdV-41 morphogenesis. In the late phase of viral replication, the membrane integrity of the infected cells was lost and viral particles were released extracellularly. This study reveals the partial process of HAdV-41 morphogenesis and provides more biological information on HAdV-41.


Sujet(s)
Infections humaines à adénovirus/virologie , Adénovirus humains/croissance et développement , Adénovirus humains/ultrastructure , Adénovirus humains/génétique , Adénovirus humains/physiologie , Membrane cellulaire/virologie , Noyau de la cellule/virologie , Humains , Libération de particules virales , Réplication virale
20.
Chinese Journal of Virology ; (6): 154-161, 2014.
Article de Chinois | WPRIM (Pacifique Occidental) | ID: wpr-356622

RÉSUMÉ

To investigate the morphogenetic process of human adenovirus type 41 (HAdV-41), 293TE cells were infected with purified wild-type HAdV-41, and ultrathin sections of infected cells were prepared and observed under a transmission electron microscope. Results showed that HAdV-41 entered host cells mainly through three ways: non-clathrin-coated pit, clathrin-coated pit, and direct penetration of plasma membrane. In addition, cell microvilli might help HAdV-41 enter cells. After entering into cells, HAdV-41 virus particles could be found in vacuoles or lysosomes or be in a free state in cytoplasm. Only free virus particles could be found near nuclear pores (NP), suggesting that the virus needed to escape from lysosomes for effective infection and viral nucleoprotein entered the nucleus through NP. Progeny viruses were as-sembled in the nucleus. Three types of inclusion bodies, which were termed as fibrillous inclusion body, condense inclusion body, and stripped condense inclusion body, were involved in HAdV-41 morphogenesis. In the late phase of viral replication, the membrane integrity of the infected cells was lost and viral particles were released extracellularly. This study reveals the partial process of HAdV-41 morphogenesis and provides more biological information on HAdV-41.


Sujet(s)
Humains , Infections humaines à adénovirus , Virologie , Adénovirus humains , Génétique , Physiologie , Membrane cellulaire , Virologie , Noyau de la cellule , Virologie , Libération de particules virales , Réplication virale
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