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1.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 31(5): 1543-1549, 2023.
Artículo en Chino | MEDLINE | ID: mdl-37846714

RESUMEN

OBJECTIVE: To modified the classic dithiothreitol (DTT) method for treating red blood cells (RBCs) in Technical Manual of American Association of Blood Banks(AABB) and evaluate its application value in pre-transfusion examination of patients treated with daratumumab. METHODS: The classic 0.2 mol/L DTT method was improved in terms of PBS, DTT concentration, donor RBCs concentration (suspended/packed) and sample processing time. The modified DTT methods and AABB classic DTT method were applied to the blood matching tests of 12 multiple myeloma patients treated with daratumumab. The effect of treating panel RBCs with modified DTT methods on the detection of other irregular antibodies was evaluated by using antiserum and antibody reagents with known antibody properties. RESULTS: Two modified DTT methods were established (method 1: changed the concentration of DTT to 0.01 mol/L; method 2: changed the concentration of DTT to 0.02 mol/L and replaced the packed RBCs with 3% RBCs suspension). The optimal treatment time was 35 min for the modified DTT methods. At this time, the pan-agglutination caused by daratumumab was eliminated, but the detection of antibodies such as anti-E, anti-JKa, anti-M were not affected, and the titer of anti-K antibodies was only slightly decreased. CONCLUSION: The modified DTT methods were effective, which can eliminate the interference of daratumumab while retaining the activity of the Kell blood group system, and can replace the current classic DTT method in AABB Technical Manual.

2.
Polymers (Basel) ; 15(8)2023 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-37112112

RESUMEN

In this study, butadiene sulfone (BS) was selected as an efficient electrolyte additive to stabilize the solid electrolyte interface (SEI) film on the lithium titanium oxide (LTO) electrodes in Li-ion batteries (LIBs). It was found that the use of BS as an additive could accelerate the growth of stable SEI film on the LTO surface, leading to the improved electrochemical stability of LTO electrodes. It can be supported by the BS additive to effectively reduce the thickness of SEI film, and it significantly enhances the electron migration in the SEI film. Consequently, the LIB-based LTO anode in the electrolyte containing 0.5 wt.% BS showed a superior electrochemical performance to that in the absence of BS. This work provides a new prospect for an efficient electrolyte additive for next-generation LIBs-based LTO anodes, especially when discharged to low voltage.

3.
Chem Commun (Camb) ; 58(93): 12943-12946, 2022 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-36321565

RESUMEN

Compounds with the benzisothiazol-3-one (BIT) skeleton perform excellently in the pharmaceutical field, although current synthetic methods remain limited in terms of synthetic efficiency. Herein, we report the catalytic intramolecular N-S bond formation for BITs from easily prepared disulfide precursors by an Fe(III) dithiolate through O2 activation at 298 K. Interestingly, the catalytic performance is enhanced by substituting O2 with a milder O-donor oxidant, ONMe3. Catalytic oxygenation of PPh3 to OPPh3 can also proceed under similar conditions. In addition, the first anionic monosulfenato Fe(III) species, Fe(III)-S(O)R, is isolated with structural characterization from the reaction of Fe(III) thiolate and ONMe3.


Asunto(s)
Compuestos Férricos , Estrés Oxidativo , Compuestos Férricos/química , Ligandos , Oxidación-Reducción , Catálisis
4.
Nano Lett ; 22(16): 6655-6663, 2022 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-35925801

RESUMEN

The miniaturization and integration of optoelectronic devices require progressive size reduction of active layers, resulting in less optical absorption and lower quantum efficiency. In this work, we demonstrate that introducing a metasurface made of hybrid organic-inorganic perovskite (HOIP) can significantly enhance broadband absorption and improve photon-to-electron conversion, which roots from exciting Mie resonances together with suppressing optical transmission. On the basis of the HOIP metasurface, a broadband photodetector has been fabricated where photocurrent boosts more than 10 times in the frequency ranging from ultraviolet to visible. The device response time is less than 5.1 µs at wavelengths 380, 532, and 710 nm, and the relevant 3 dB bandwidth is over 0.26 MHz. Moreover, this photodetector has been applied as a signal receiver for transmitting 2D color images in broadband optical communication. These results accentuate the practical applications of HOIP metasurfaces in novel optoelectronic devices for broadband optical communication.

5.
Opt Lett ; 47(3): 565-568, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-35103672

RESUMEN

Most polarization-sensitive photodetectors detect either linearly polarized (LP) or circularly polarized (CP) light. Here, we experimentally demonstrate a multiple-polarization photodetector based on a hybrid organic-inorganic perovskite (HOIP) metasurface, which is sensitive to both LP and CP light simultaneously. The perovskite metasurface is composed of a HOIP antenna array on a single-crystal HOIP film. Owing to the antenna anisotropy, the absorption of linearly polarized light at the metasurface depends on the polarization angle; also, due to the mirror asymmetry of the antenna elements, the metasurface is also sensitive to different circular polarizations. Polarization-dependent photocurrent responses to both LP and CP light are detected. Our results highlight the potential of perovskite metasurfaces for integrated photoelectric applications.

6.
Huan Jing Ke Xue ; 43(1): 306-313, 2022 Jan 08.
Artículo en Chino | MEDLINE | ID: mdl-34989515

RESUMEN

To explore the composition of the nirS denitrifying bacterial community during stratification in spring(March to May) in a drinking water reservoir and its relationship with water quality, the water quality and relative abundance and structure of the denitrifying bacterial community were analyzed using in-situ monitoring coupled with Illumina high-throughput sequencing technology in the Lijiahe Reservoir. The results showed that:① through high-throughput sequencing, 4 phyla and 13 genera were identified. The dominant bacterial phylum was Proteobacteria, and its relative abundance was between 52.5% and 70.6%. The overall trend of the relative abundance of Proteobacteria decreased on the time scale (P<0.05), and its relative abundance in the surface and middle layers was higher than that of the bottom layer on the spatial scale (P<0.05). There was no difference in the proportion of Proteobacteria between the surface and middle layers (P>0.05), and the abundance of its bottom layer was relatively stable; eight genera of bacteria with denitrification function were identified, among which the dominant bacterial genera (relative abundance>1%) were Dechloromonas and Pseudomonas. The relative abundance of Dechloromonas showed a trend of first decreasing and then increasing on the time scale, whereas the relative abundance of Pseudomonas showed a trend of increasing first and then decreasing on the time scale. There were no differences on the spatial scale between these two genera (P>0.05); the changes in bacterial diversity and abundance were basically similar, with a trend of first increasing and then decreasing on the time scale. The highest diversity and abundance of the bacterial community gradually increased with increasing depth on the spatial scale. ② ρ(TN) of the reservoir during stratification was 2.35-2.91 mg·L-1, and the nitrogen pollution was more serious. In March and April, ρ(TN) on the vertical scale was basically similar and showed a decreasing trend. In May, the content of total nitrogen was higher than that in March and April, and the highest value of total nitrogen content occurred in the surface layer. ③ Redundancy analysis showed that water temperature, dissolved oxygen, nitrate, and ammonia nitrogen were the main driving factors, and ammonia nitrogen showed a significantly negative correlation with Dechlormonas. In summary, the study of nirS-type denitrification communities and related influencing factors will contribute to analyzing the characteristics of denitrifying bacterial community changes in a micro-polluted drinking water reservoir and provide a theoretical research basis for the biological remediation of nitrogen pollution in such reservoirs in the future.


Asunto(s)
Bacterias , Desnitrificación , Bacterias/genética , Nitratos , Nitrógeno/análisis , Calidad del Agua
7.
Sci Adv ; 7(37): eabj0935, 2021 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-34516883

RESUMEN

Rough surfaces lead to diffused light in both reflection and transmission, thereby blurring the reflected and transmitted images. Here, we merge the traditionally incompatible diffuse reflection and undistorted transmission by introducing the concept of random-flip metasurfaces made of randomly flipped components. These metasurfaces have a globally random phase in reflection that leads to diffuse reflection, while the local space inversion and reciprocity principle ensure distortion-free transmission. Notably, the metasurface reflects like a rough surface yet transmits like a smooth one in a broad spectrum. On the basis of complementary random arrays of gold nanorods, we verified this functionality by both optical spectroscopy and imaging experiments over a broad range of frequencies from the visible to the infrared regime. This feature, which originates from breaking the phase correlation between reflection and transmission by the metasurface, could enable a range of new optical materials and display technology.

8.
Small ; 17(31): e2101282, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34173329

RESUMEN

Phase change materials (PCMs), such as GeSbTe (GST) alloys and vanadium dioxide (VO2 ), play an important role in dynamically tunable optical metadevices. However, the PCMs usually require high thermal annealing temperatures above 700 K, but most flexible metadevices can only work below 500 K owing to the thermal instability of polymer substrates. This contradiction limits the integration of PCMs into flexible metadevices. Here, a mica sheet is chosen as the chemosynthetic support for VO2 and a smooth and uniformly flexible phase change material (FPCM) is realized. Such FPCMs can withstand high temperatures while remaining mechanically flexible. As an example, a metal-FPCM-metal infrared meta-absorber with mechanical flexibility and electrical tunability is demonstrated. Based on the electrically-tuned phase transition of FPCMs, the infrared absorption of the metadevice is continuously tuned from 20% to 90% as the applied current changes, and it remains quite stable at bending states. The metadevice is bent up to 1500 times, while no visible deterioration is detected. For the first time, the FPCM metastructures are significantly added to the flexible material family, and the FPCM-based metadevices show various application prospects in electrically-tunable conformal metadevices, dynamic flexible photodetectors, and active wearable devices.


Asunto(s)
Electricidad
9.
Opt Express ; 29(12): 19170-19182, 2021 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-34154158

RESUMEN

Ultrathin hybrid organic-inorganic perovskite (HOIP) films have significant potential for use in integrated high-performance photoelectric devices. However, the relatively low optical absorption capabilities of thinner films, particularly in the long-wavelength region, pose a significant challenge to the further improvement of photoelectrical conversion in ultrathin HOIP films. To address this problem, we propose a combining of ultrathin HOIP film with plasmonic metasurface to enhance the absorption of the film effectively. The metasurface excites localized surface plasmon resonances and deflects the reflected light within the HOIP film, resulting in an obvious enhancement of film absorption. Finite-difference time-domain simulation results reveal that the far-field intensities, deflection angles, and electric field distributions can be effectively varied by using metasurfaces with different arrangements. Examination of the reflection and absorption spectra reveals that embedding a specifically designed metasurface into the HOIP film produces an obvious enhancement in broadband optical absorption compared with pure HOIP films. We further demonstrate that this broadband absorption promotion mechanism can be effective at a wide range of HOIP film thicknesses. Comparison of the absorption spectra at various incidence angles of ultrathin HOIP films with and without underlying metasurfaces indicates that the addition of a metasurface can effectively promote absorption under wide-angle incident light illumination. Moreover, by extending the metasurface structure to a two-dimensional case, absorption enhancements insensitive to the incident polarization states have also been demonstrated. This proposed metasurface-assisted absorption enhancement method could be applied in designing novel high-performance thin-film solar cells and photodetectors.

10.
World J Pediatr ; 17(2): 152-163, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33829387

RESUMEN

INTRODUCTION: The efficacy of inhaled budesonide for managing moderate-to-severe acute exacerbations in children is not clear. Therefore, this study aimed to evaluate hospital admission rates, need for use of systemic corticosteroids, length of hospital stay and adverse events when inhaled budesonide is added to standard pediatric emergency department management of moderate-to-severe acute exacerbations of asthma. METHODS: A systematic search was conducted in PubMed, Scopus, CENTRAL (Cochrane Central Register of Controlled Trials) and Google scholar databases. Randomized controlled trials that evaluated the effect of nebulized budesonide in moderate-to-severe acute exacerbations of asthma in pediatric patients were included for this meta-analysis. Statistical analysis was done using STATA version 13.0. RESULTS: A total of 16 RCTs were included. Children receiving nebulized budesonide had 43% lower risk of being hospitalized (RR 0.57; 95% CI, 0.39; 0.85) and 66% lower risk of requiring systemic corticosteroids (RR 0.34; 95 % CI, 0.21; 0.55) compared with those receiving placebo. There were no differences in the length of hospital stay (Hedges's g standardized mean difference - 1.53; 95% CI, - 3.64; 0.58) and risk of adverse events (RR 0.87, 95% CI; 0.65; 1.17) between the two groups. There was no evidence of publication bias for any of the outcomes considered. CONCLUSION: The findings of this meta-analysis support the use of inhaled budesonide in reducing risk of hospitalization and the need for systemic corticosteroids among children with acute moderate-to-severe asthma exacerbation.


Asunto(s)
Asma/tratamiento farmacológico , Broncodilatadores/uso terapéutico , Budesonida/uso terapéutico , Servicio de Urgencia en Hospital , Hospitalización/estadística & datos numéricos , Niño , Humanos , Tiempo de Internación/estadística & datos numéricos , Ensayos Clínicos Controlados Aleatorios como Asunto
11.
Huan Jing Ke Xue ; 42(3): 1391-1402, 2021 Mar 08.
Artículo en Chino | MEDLINE | ID: mdl-33742936

RESUMEN

To explore the influence of storm runoff on reservoir organic matter during the flood season, the Lijiahe Reservoir was selected to analyze variations in the content and components of dissolved organic matter (DOM) during four periods (before runoff, flood peak period, 1 week after runoff, and 6 weeks after runoff) using three-dimensional fluorescence spectroscopy parallel factor analysis (EEMs-PARAFAC) and ultraviolet-visible (UV-Vis) spectra. The results showed that:① the turbidity and DOC content of the reservoir increased significantly during the flood peak period (P<0.01) and gradually decreased thereafter; ② the UV-Vis spectrum characteristics showed that a(254) and a(355) were significantly increased in the flood peak period (P<0.01) while E2/E3 and E3/E4 were significantly decreased (P<0.01), indicating that the concentration, relative molecular weight, and degree of DOM humification in the reservoir were increased by storm runoff; ③ four DOM components were identified as terrestrial humus (C1 and C2), microbial humus (C3), and a tryptophan-like component (C4). The fluorescence intensity of the C1-C3 components increased significantly during the flood peak period (P<0.05), indicating that the increase in the DOM humic-like component was caused by the storm runoff. At the same time, a decrease in the fluorescence intensity of the C1-C4 components was observed after the flood peak period, indicating that DOM continuously settled and degraded after runoff; and ④ Pearson's correlation analyses showed that DOM fluorescence intensity and turbidity were significantly correlated (r>0.467, P<0.05), indicating that the observed decrease in DOM content was related to the sedimentation of suspended solids. A principal component analysis (PCA) showed that the water quality in the reservoir reflected the observed characteristics during the different runoff periods. Overall, this study reveals the effects of the storm runoff on DOM content and its components over the short and long term, providing scientific support for the management of drinking water quality.

12.
Huan Jing Ke Xue ; 41(11): 5201-5214, 2020 Nov 08.
Artículo en Chino | MEDLINE | ID: mdl-33124265

RESUMEN

Olfactory microorganisms mainly include actinomycetes, algae, and myxobacteria, and are widely found in typical water ecosystems such as water source reservoirs, lakes, streams, and oceans. Biologically-derived taste and odor compounds can cause severe off-flavor problems at trace concentrations, threatening the safety of water supplies. Physical and chemical methods have been implemented, but they need to be improved and optimized. Microbial methods show attractive prospects due to their environmentally friendly characteristics. This article reviews the literature regarding the types, biological sources, detection methods, control measures, influencing factors, and odor-producing mechanisms of microbial methods. Future research directions and fields of investigation are discussed in order to promote the related research of taste and odor compounds and ensure the safety of urban water supplies.


Asunto(s)
Odorantes , Gusto , Ecosistema , Lagos , Abastecimiento de Agua
13.
Nano Lett ; 20(10): 7144-7151, 2020 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-32941049

RESUMEN

Flexible optoelectronic devices attract considerable attention due to their prominent role in creating novel wearable apparatus for bionics, robotics, health care, and so forth. Although bulk single-crystalline perovskite-based materials are well-recognized for the high photoelectric conversion efficiency than the polycrystalline ones, their stiff and brittle nature unfortunately prohibits their application for flexible devices. Here, we introduce ultrathin single-crystalline perovskite film as the active layer and demonstrate a high-performance flexible photodetector with prevailing bending reliability. With a much-reduced thickness of 20 nm, the photodetector made of this ultrathin film can achieve a significantly increased responsivity as 5600A/W, 2 orders of magnitude higher than that of recently reported flexible perovskite photodetectors. The demonstrated 0.2 MHz 3 dB bandwidth further paves the way for high-speed photodetection. Notably, all its optoelectronic characteristics resume after being bent over thousands of times. These results manifest the great potential of single-crystalline perovskite ultrathin films for developing wearable and flexible optoelectronic devices.

14.
Opt Lett ; 42(14): 2834-2837, 2017 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-28708181

RESUMEN

In this work, we demonstrate polarization-dependent strong coupling between surface plasmon polaritons (SPPs) and excitons in the J-aggregates-attached aperture array. It is shown that the excitons strongly couple with the polarization-dependent SPPs, and Rabi splittings are consequently observed. As a result, the polarization-dependent polariton bands are generated in the system. Increasing the incident angle, the polaritons disperse to higher energies under transverse-electric illumination, while the polaritons disperse to lower energies under transverse-magnetic illumination. Therefore, at different polarization incidence, we experimentally achieve distinct polaritons with opposite dispersion directions. In this way, tuning the polarization of the incident light, we can excite different polaritons whose energy propagates to different directions. Furthermore, by retrieving the mixing fractions of the components in these polariton bands, we find that the dispersion properties of the polaritons are inherited from both the SPPs and the excitons. Our investigation may inspire related studies on tunable photon-exciton interactions and achieve some potential applications on active polariton devices.

15.
Nan Fang Yi Ke Da Xue Xue Bao ; 36(4): 582-7, 2016 Apr.
Artículo en Chino | MEDLINE | ID: mdl-27113192

RESUMEN

OBJECTIVE: To construct a recombinant human adenovirus type 5 (Ad5) expressing luciferase and GFP reporter gene and detect neutralizing antibodies against adenovirus type 5 in common marmosets (Callithrix jacchus) to provide basic laboratory data for evaluating adenovirus vaccines. METHODS: Luciferase and GFP reporter genes from plasmid pHAGE-CMV-GFP were inserted into pDC315 to construct the recombinant adenovirus shutter plasmid pDC315-Luc-GFP. The shutter plasmid was co-transduced with pBHGlox(delta)E1,3Cre in 293A cell line to package the recombinant adenovirus rAd5/Luc/GFP. Three rounds of plaque formation experiment were performed to select the monoclonal adenovirus followed by purification with cesium chloride density gradient centrifugation and virus titration with TCID50 method. Chemiluminescence assay and flow cytometry were employed to detect the neutralizing antibody levels in 14 common marmosets. RESULTS: The shuttle plasmid pDC315-Luc-GFP was successfully constructed and the recombinant adenovirus rAd5/Luc/GFP was packaged with a the titer reaching 6.9×10(11.5) PFU/mL. In the 14 marmosets, chemiluminescence assay identified 4 (28.6%) marmosets that were positive for Ad5-neutralizing antibodies, including 2 with a antibody titer of 1/16 and another 2 with a titer of 1/32; flow cytomery detected Ad5-neutralizing antibodies in 3 marmosets at the titer of 1/16. CONCLUSION: Chemiluminescence assay is a simple, sensitive, and accurate modality for detecting Ad5-neutralizing antibodies. Common marmosets have a very low positivity rate for Ad5-neutralizing antibodies and are therefore promising models for studying adenovirus-based vaccines and therapies.


Asunto(s)
Adenovirus Humanos/inmunología , Anticuerpos Neutralizantes/sangre , Anticuerpos Antivirales/sangre , Callithrix , Inmunidad Humoral , Animales , Línea Celular , Humanos , Luciferasas , Plásmidos
16.
Transfus Apher Sci ; 53(3): 315-9, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26141516

RESUMEN

BACKGROUND: The assumption that the level of safety of voluntary non-remunerated donors is significantly higher than that of family replacement donors is supported by global data without stratifying for first-time or repeat volunteer, or according to age, but the viral marker prevalence between replacement donors and first-time voluntary non-remunerated donors is similar. MATERIALS AND METHODS: From 2006 to 2013, replacement and voluntary donors were respectively recruited by the hospitals and the Center Blood Station in Zhaoqing, Guangdong, according to the existing procedures, and all the donors were screened for hepatitis B virus (HBV) surface antigen (HBsAg), antibodies against hepatitis C virus (anti-HCV), human immunodeficiency virus (anti-HIV) (1 + 2) and Treponema pallidum (anti-TP) by the enzyme immunoassays (EIAs), and alanine aminotransferase (ALT) in the Center Blood Station by kinetic analysis method. The risk factors related to blood safety were analyzed by Binary logistic regression analysis. RESULTS: Between 252,202 volunteers and 2771 replacement donors, the prevalences of ALT > 40 U/L and anti-HIV (4.88% and 0.01% vs 4.44% and 0.07%, respectively) were not significantly different. The prevalences of HBsAg, anti-HCV and anti-syphilis in replacement group were higher than those in voluntary group, which were related to donor's sex, age and donation time. Overall prevalence of serological markers was higher in male replacement donors than in female, and in replacement donor over 30 years than in those below 30 years, but the positive prevalence in repeated replacement donors was lower than that in first-time replacement donors. CONCLUSIONS: With appropriate intervention measures, such as pre-donor screening and other donor selection policy, replacement donors and voluntary donors provide a similar level of viral safety. Our donor selection policy in future should focus on retaining both young replacement and young voluntary donors as repeat donors and promoting the donation proportion of females, which will improve blood safety.


Asunto(s)
Donantes de Sangre , Seguridad de la Sangre , Selección de Donante , Hepatitis B/sangre , Hepatitis C/sangre , Sífilis/sangre , Adulto , China/epidemiología , Femenino , Hepatitis B/epidemiología , Hepatitis C/epidemiología , Humanos , Masculino , Sífilis/epidemiología
17.
Virology ; 476: 364-371, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25589239

RESUMEN

Adenosine deaminases that act on RNA (ADARs) have been reported to be functional on various viruses. ADAR1 may exhibit antiviral or proviral activity depending on the type of virus. Human immunodeficiency virus (HIV)-1 is the most well-studied lentivirus with respect to its interaction with ADAR1, and variable results have been reported. In this study, we demonstrated that equine ADAR1 (eADAR1) was a positive regulator of equine infectious anemia virus (EIAV), another lentivirus of the Retroviridae family. First, eADAR1 significantly promoted EIAV replication, and the enhancement of viral protein expression was associated with the long terminal repeat (LTR) and Rev response element (RRE) regions. Second, the RNA binding domain 1 of eADAR1 was essential only for enhancing LTR-mediated gene expression. Third, in contrast with APOBEC proteins, which have been shown to reduce lentiviral infectivity, eADAR1 increased the EIAV infectivity. This study indicated that eADAR1 was proviral rather than antiviral for EIAV.


Asunto(s)
Adenosina Desaminasa/metabolismo , Anemia Infecciosa Equina/enzimología , Virus de la Anemia Infecciosa Equina/fisiología , Virus de la Anemia Infecciosa Equina/patogenicidad , ARN Bicatenario/metabolismo , ARN Viral/metabolismo , Replicación Viral , Adenosina Desaminasa/genética , Animales , Línea Celular , Anemia Infecciosa Equina/genética , Anemia Infecciosa Equina/virología , Caballos , Interacciones Huésped-Patógeno , Virus de la Anemia Infecciosa Equina/genética , Estructura Terciaria de Proteína , ARN Bicatenario/genética , ARN Viral/química , ARN Viral/genética , Secuencias Repetidas Terminales , Virulencia
18.
J Virol ; 88(21): 12296-310, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25122784

RESUMEN

UNLABELLED: Viperin is an endoplasmic reticulum (ER)-associated multifunctional protein that regulates virus replication and possesses broad antiviral activity. In many cases, viperin interferes with the trafficking and budding of viral structural proteins by distorting the membrane transportation system. The lentivirus equine infectious anemia virus (EIAV) has been studied extensively. In this study, we examined the restrictive effect of equine viperin (eViperin) on EIAV replication and investigated the possible molecular basis of this restriction to obtain insights into the effect of this cellular factor on retroviruses. We demonstrated that EIAV infection of primary equine monocyte-derived macrophages (eMDMs) upregulated the expression of eViperin. The overexpression of eViperin significantly inhibited the replication of EIAV in eMDMs, and knockdown of eViperin transcription enhanced the replication of EIAV in eMDMs by approximately 45.8%. Further experiments indicated that eViperin restricts EIAV at multiple steps of viral replication. The overexpression of eViperin inhibited EIAV Gag release. Both the α-helix domain and radical S-adenosylmethionine (SAM) domain were required for this activity. However, the essential motifs in SAM were different from those reported for the inhibition of HIV-1 Gag by human viperin. Furthermore, eViperin disrupted the synthesis of both EIAV Env and receptor, which consequently inhibited viral production and entry, respectively, and this disruption was dependent on the eViperin α-helix domain. Using immunofluorescence assays and electron microscopy, we demonstrated that the α-helix domain is responsible for the distortion of the endoplasmic reticulum (ER). Finally, EIAV did not exhibit counteracting eViperin at the protein level. IMPORTANCE: In previous studies, viperin was indicated as restricting virus replications primarily by the inhibition of virus budding. Here, we show that viperin may have multiple antiviral mechanisms, including the reduction of EIAV Gag budding and Env expression, and these activities are dependent on different viperin domains. We especially demonstrate that the overexpression of viperin inhibits EIAV entry by decreasing the level of virus receptor. Therefore, viperin restriction of viruses is determined largely by the dependence of virus on the cellular membrane transportation system.


Asunto(s)
Retículo Endoplásmico/metabolismo , Retículo Endoplásmico/virología , Interacciones Huésped-Patógeno , Virus de la Anemia Infecciosa Equina/inmunología , Virus de la Anemia Infecciosa Equina/fisiología , Proteínas Virales/metabolismo , Replicación Viral , Animales , Células Cultivadas , Retículo Endoplásmico/ultraestructura , Técnica del Anticuerpo Fluorescente , VIH-1 , Caballos , Macrófagos/inmunología , Macrófagos/virología , Microscopía Electrónica , Liberación del Virus
19.
Nan Fang Yi Ke Da Xue Xue Bao ; 31(2): 234-8, 2011 Feb.
Artículo en Chino | MEDLINE | ID: mdl-21354900

RESUMEN

OBJECTIVE: To compare different methods commonly used for titering adenovirus and analyze the advantages and limitations of each method. METHODS: Four recombined adenoviruses (Ad-G-AT2R-EGFP, Ad-CMV-EGFP, Ad-mif-shRNA-EGFP and Ad-CBA-GFP) were amplified and purified, and each was titered by optical absorbance, real-time PCR, green fluorescent protein (GFP)-labeled method, immunoassay, and cytopathic effect (CPE). The results were then comparatively analyzed. RESULTS: No significant difference was found in the titer amounts derived from GFP-labeled method, immunoassay, and cytopathic effect method (P>0.1). A positive correlation was noted in the titer amounts determined by real-time PCR and immunoassay (r=0.965), even though the value (vg/ml) obtained by real-time PCR was 10 times higher than that by immunoassay (ifu/ml). CONCLUSION: GFP-labeled method and immunoassay allow rapid determination of the adenoviral titer. Real-time PCR can not directly determine the real infectious titer of the adenovirus, but the result is well correlated to that of immunoassay and reflects, though indirectly, the actual infectious titer of adenovirus. Considering the procedural convenience and shorter time consumption, real-time PCR is still a practical method for adenoviral titration.


Asunto(s)
Adenoviridae/aislamiento & purificación , Proteínas de la Cápside/metabolismo , Proteínas Fluorescentes Verdes/metabolismo , Ensayo de Placa Viral/métodos , Replicación Viral , Adenoviridae/metabolismo , Adenoviridae/fisiología , ADN Viral/aislamiento & purificación , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos
20.
Nan Fang Yi Ke Da Xue Xue Bao ; 29(8): 1548-50, 2009 Aug.
Artículo en Chino | MEDLINE | ID: mdl-19726288

RESUMEN

OBJECTIVE: To construct the expression vectors of GPC-3 CTL epitope. METHODS: The HBsAg gene with three different EYILSLEEL (EYI) sites was named EYI1, and another with one EYI replacing CTL epitope FLG or SIL of pcHBsAg were named EYI2 and EYI3, respectively. All the three DNAs were amplified by SEOing PCR from pcHBsAg plasmid and linked into pBSSK+ vector to construct Pbssk/EYI1, pBSSK/EYI2, and pBSSK/EYI3. The three plasmid were identified by PCR, double digestion and sequencing, and the fragments with EYI1-3 were obtained by double digestion and then inserted into pcDNA3.1+ vector. RESULTS AND CONCLUSION: PCR, enzyme digestion and sequence analysis confirmed successful construction of the eukaryotic expression vectors pcDNA-EYI1/HBsAg, pcDNA-EYI2/HBsAg, pcDNA-EYI3/HBsAg, which facilitate further studies of the GPC3-HBsAg multiple peptides vaccine for HBV infection.


Asunto(s)
Epítopos/genética , Vectores Genéticos/genética , Glipicanos/genética , Glipicanos/inmunología , Linfocitos T Citotóxicos/inmunología , Secuencia de Aminoácidos , Epítopos/química , Epítopos/inmunología , Glipicanos/metabolismo , Antígenos de Superficie de la Hepatitis B/genética , Antígenos de Superficie de la Hepatitis B/inmunología , Plásmidos/genética , Plásmidos/metabolismo , Reacción en Cadena de la Polimerasa , Vacunas de Subunidad/química , Vacunas de Subunidad/genética , Vacunas de Subunidad/inmunología
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