Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 96
Filtrar
1.
J Virol ; 98(4): e0184423, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38436247

RESUMO

Porcine Mx1 is a type of interferon-induced GTPase that inhibits the replication of certain RNA viruses. However, the antiviral effects and the underlying mechanism of porcine Mx1 for porcine reproductive and respiratory syndrome virus (PRRSV) remain unknown. In this study, we demonstrated that porcine Mx1 could significantly inhibit PRRSV replication in MARC-145 cells. By Mx1 segment analysis, it was indicated that the GTPase domain (68-341aa) was the functional area to inhibit PRRSV replication and that Mx1 interacted with the PRRSV-N protein through the GTPase domain (68-341aa) in the cytoplasm. Amino acid residues K295 and K299 in the G domain of Mx1 were the key sites for Mx1-N interaction while mutant proteins Mx1(K295A) and Mx1(K299A) still partially inhibited PRRSV replication. Furthermore, we found that the GTPase activity of Mx1 was dominant for Mx1 to inhibit PRRSV replication but was not essential for Mx1-N interaction. Finally, mechanistic studies demonstrated that the GTPase activity of Mx1 played a dominant role in inhibiting the N-Nsp9 interaction and that the interaction between Mx1 and N partially inhibited the N-Nsp9 interaction. We propose that the complete anti-PRRSV mechanism of porcine Mx1 contains a two-step process: Mx1 binds to the PRRSV-N protein and subsequently disrupts the N-Nsp9 interaction by a process requiring the GTPase activity of Mx1. Taken together, the results of our experiments describe for the first time a novel mechanism by which porcine Mx1 evolves to inhibit PRRSV replication. IMPORTANCE: Mx1 protein is a key mediator of the interferon-induced antiviral response against a wide range of viruses. How porcine Mx1 affects the replication of porcine reproductive and respiratory syndrome virus (PRRSV) and its biological function has not been studied. Here, we show that Mx1 protein inhibits PRRSV replication by interfering with N-Nsp9 interaction. Furthermore, the GTPase activity of porcine Mx1 plays a dominant role and the Mx1-N interaction plays an assistant role in this interference process. This study uncovers a novel mechanism evolved by porcine Mx1 to exert anti-PRRSV activities.


Assuntos
Proteínas de Resistência a Myxovirus , Síndrome Respiratória e Reprodutiva Suína , Vírus da Síndrome Respiratória e Reprodutiva Suína , Proteínas não Estruturais Virais , Replicação Viral , Animais , Linhagem Celular , Interferons/imunologia , Interferons/metabolismo , Mutação , Proteínas de Resistência a Myxovirus/química , Proteínas de Resistência a Myxovirus/genética , Proteínas de Resistência a Myxovirus/metabolismo , Síndrome Respiratória e Reprodutiva Suína/enzimologia , Síndrome Respiratória e Reprodutiva Suína/metabolismo , Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/crescimento & desenvolvimento , Vírus da Síndrome Respiratória e Reprodutiva Suína/metabolismo , Ligação Proteica , Suínos/virologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Proteínas não Estruturais Virais/metabolismo
2.
Opt Express ; 32(7): 11737-11750, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38571014

RESUMO

This paper provides an extensive discussion of a complex amplitude-based dynamic three-dimensional deformation measurement method, in which the phase and amplitude of the speckle field are used for out-of-plane and in-plane deformation calculation respectively. By determining the optimal polarization states of the speckle field and reference field from the comprehensive analysis of measurement mathematical model in the principle of polarization multiplexing, the 3-step phase-shifting interferograms and one speckle gram can be directly recorded by a polarization camera in a single shot. The out-of-plane deformation would be recovered from the subtraction of speckle phases that are demodulated by a special least square algorithm; speckle gram with improved quality is offered for correlation computation to obtain in-plane deformation. The advancement and significance of the optimized strategy are intuitively demonstrated by comparing the measurement accuracy under different combinations of polarization states. Finally, the dynamic thermal deformation experiment reveals the potential in practical real-time applications.

3.
Diabetes Obes Metab ; 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39021354

RESUMO

AIMS: To investigate the impact of various clinical factors associated with Graves' disease on the success rate of radioiodine (RAI) therapy for Graves' disease within 3 years, and to determine the optimal range of iodine dosage per unit volume that yields the highest cure rate for Graves' disease within 1 year. MATERIALS AND METHODS: This retrospective study included patients diagnosed with Graves' disease who underwent RAI therapy at the Second Affiliated Hospital of Anhui Medical University between October 2012 and October 2022. The cumulative success rate was analysed using the Kaplan-Meier method. Univariate and multivariate Cox proportional hazards regression models were employed to evaluate factors associated with successful treatment of Graves' disease. Outcomes were categorized as either success or failure for all patients. RESULTS: Overall, 1994 patients were enrolled in this study, including 594 (29.8%) male and 1399 (70.2%) female patients. The success and failure groups comprised 1645 (82.4%) and 349 patients (17.6%), respectively, after a 3-year follow-up period. Multivariate regression analysis demonstrated that sex, antithyroid drug (ATD) use before RAI therapy, age, thyroid receptor antibody (TRAb) levels, iodine dose, thyroid mass, and early ATD use before RAI therapy were independent influencing factors for Graves' disease cure. CONCLUSIONS: We found that female patients and those with TRAbs ≥31.83 IU/L and thyroid mass ≥ 73.42 g had a lower cure rate. Therefore, thyroid size, disease severity, and duration of disease should be comprehensively considered when making treatment decisions and iodine dose selection in clinical practice.

4.
Diabetes Obes Metab ; 26(3): 901-910, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38100147

RESUMO

AIM: To assess the safety, tolerability, pharmacokinetics (PKs) and pharmacodynamics of HRS-7535, a novel glucagon-like peptide-1 receptor agonist (GLP-1RA), in healthy participants. MATERIALS AND METHODS: This phase 1 trial consisted of single-ascending dose (SAD), food effect (FE) and multiple-ascending dose (MAD) parts. In the SAD part, participants were randomized (6:2) to receive HRS-7535 (at doses of 15, 60 and 120 mg; administered orally once daily) or placebo. In the FE part, participants were randomized (8:2) to receive a single dose of 90-mg HRS-7535 or placebo, in both fed and fasted states. In the MAD part, participants were randomized (18:6) to receive daily HRS-7535 (120 mg [30/60/90/120-mg titration scheme]) or placebo for 28 days. The primary endpoints were safety and tolerability. RESULTS: Nausea and vomiting were the most frequently reported AEs across all three parts. In the SAD part, the median Tmax was 5.98-5.99 hours and the geometric mean t1/2 was 5.28-9.08 hours across the HRS-7535 dosing range. In the MAD part, the median Tmax was 5.98-10.98 hours and the geometric mean t1/2 was 6.48-8.42 hours on day 28 in participants on HRS-7535. PKs were approximately dose-proportional. On day 29 in the MAD part, the mean (percentage) reduction in body weight from baseline was 4.38 kg (6.63%) for participants who received HRS-7535, compared with 0.8 kg (1.18%) for those participants who received a placebo. CONCLUSIONS: HRS-7535 exhibited a safety and tolerability profile consistent with other GLP-1RAs and showed PKs suitable for once-daily dosing. These findings support further clinical development of HRS-7535 for type 2 diabetes.


Assuntos
Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Agonistas do Receptor do Peptídeo 1 Semelhante ao Glucagon , Voluntários Saudáveis , Peso Corporal , Área Sob a Curva , Método Duplo-Cego , Relação Dose-Resposta a Droga
5.
J Virol ; 96(17): e0061222, 2022 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-36005757

RESUMO

Protein SUMOylation represents an important cellular process that regulates the activities of numerous host proteins as well as of many invasive viral proteins. Foot-and-mouth disease virus (FMDV) is the first animal virus discovered. However, whether SUMOylation takes place during FMDV infection and what role it plays in FMDV pathogenesis have not been investigated. In the present study, we demonstrated that SUMOylation suppressed FMDV replication by small interfering RNA (siRNA) transfection coupled with pharmaceutical inhibition of SUMOylation, which was further confirmed by increased virus replication for SUMOylation-deficient FMDV with mutations in 3C protease, a target of SUMOylation. Moreover, we provided evidence that four lysine residues, Lys-51, -54, -110, and -159, worked together to confer the SUMOylation to the FMDV 3C protease, which may make SUMOylation of FMDV 3C more stable and improve the host's chance of suppressing the replication of FMDV. This is the first report that four lysine residues can be alternatively modified by SUMOylation. Finally, we showed that SUMOylation attenuated the cleavage ability, the inhibitory effect of the interferon signaling pathway, and the protein stability of FMDV 3C, which appeared to correlate with a decrease in FMDV replication. Taken together, the results of our experiments describe a novel cellular regulatory event that significantly restricts FMDV replication through the SUMOylation of 3C protease. IMPORTANCE FMD is a highly contagious and economically important disease in cloven-hoofed animals. SUMOylation, the covalent linkage of a small ubiquitin-like protein to a variety of substrate proteins, has emerged as an important posttranslational modification that plays multiple roles in diverse biological processes. In this study, four lysine residues of FMDV 3C were found to be alternatively modified by SUMOylation. In addition, we demonstrated that SUMOylation attenuated FMDV 3C function through multiple mechanisms, including cleavage ability, the inhibitory effect of the interferon signaling pathway, and protein stability, which, in turn, resulted in a decrease of FMDV replication. Our findings indicate that SUMOylation of FMDV 3C serves as a host cell defense against FMDV replication. Further understanding of the cellular and molecular mechanisms driving this process should offer novel insights to design an effective strategy to control the dissemination of FMDV in animals.


Assuntos
Cisteína Endopeptidases/metabolismo , Vírus da Febre Aftosa , Proteases Virais 3C , Animais , Antivirais , Febre Aftosa , Vírus da Febre Aftosa/genética , Interações Hospedeiro-Patógeno , Lisina/metabolismo , Peptídeo Hidrolases/metabolismo , Sumoilação , Replicação Viral
6.
Opt Express ; 31(16): 25635-25647, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37710445

RESUMO

We propose a fast and robust method for calibrating Spatial Light Modulators (SLMs) based on polarization phase-shifting interferometry. Our method effectively calibrates the SLM by addressing both the static aberration and nonlinear phase response, utilizing specially designed gray images loaded sequentially onto the SLM. Notably, we introduce a novel kinoform that effectively eliminates the influence of tilt phase shift between two shots of the polarization camera. This results in a highly accurate phase aberration map and phase modulation curve with exceptional stability, making it an ideal method to calibrate the SLM with exceptional efficiency and precision in real applications.

7.
Opt Express ; 31(21): 33830-33841, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37859154

RESUMO

This paper proposes a flexible and accurate dynamic quantitative phase imaging (QPI) method using single-shot transport of intensity equation (TIE) phase retrieval achieved by division of focal plane (DoFP) polarization imaging technique. By exploiting the polarization property of the liquid crystal spatial light modulator (LC-SLM), two intensity images of different defocus distances contained in orthogonal polarization directions can be generated simultaneously. Then, with the help of the DoFP polarization imaging, these images can be captured with single exposure, enabling accurate dynamic QPI by solving the TIE. In addition, our approach gains great flexibility in defocus distance adjustment by adjusting the pattern loaded on the LC-SLM. Experiments on microlens array, phase plate, and living human gastric cancer cells demonstrate the accuracy, flexibility, and dynamic measurement performance for various objects. The proposed method provides a simple, flexible, and accurate approach for real-time QPI without sacrificing the field of view.

8.
Opt Lett ; 48(9): 2329-2332, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37126266

RESUMO

An accurate dynamic 3D deformation measurement method realized by the combination of phase-shifting speckle interferometry and speckle correlation is proposed. By converting the speckle field and the reference field into a circular polarized and linear polarized state, the three-step phase-shifting speckle interferograms and one specklegram were recorded directly and simultaneously within a single image by using a polarization camera. Then, the out-of-plane deformation was demodulated from the synchronous phase-shifting fringe patterns, and the in-plane deformation was measured by performing correlation calculations by using specklegrams with the effect of the reference field ignored. Thus, the full-field 3D deformation was obtained precisely. Experimental results demonstrated the accuracy and dynamic measurement ability of the proposed method, which is compact and feasible for actual dynamic scenes.

9.
Brain Topogr ; 36(3): 283-293, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36856917

RESUMO

To explore alterations of resting-state functional connectivity (rsFC) in sensorimotor cortex following strokes with left or right hemiplegia considering the lateralization and neuroplasticity. Seventy-three resting-state functional near-infrared spectroscopy (fNIRS) files were selected, including 26 from left hemiplegia (LH), 21 from right hemiplegia (RH) and 26 from normal controls (NC) group. Whole-brain analyses matching the Pearson correlation were used for rsFC calculations. For right-handed normal controls, rsFC of motor components (M1 and M2) in the left hemisphere displayed a prominent intensity in comparison with the right hemisphere (p < 0.05), while for stroke groups, this asymmetry has disappeared. Additionally, RH rather than LH showed stronger rsFC between left S1 and left M1 in contrast to normal controls (p < 0.05), which correlated inversely with motor function (r = - 0.53, p < 0.05). Regarding M1, rsFC within ipsi-lesioned M1 has a negative correlation with motor function of the affected limb (r = - 0.60 for the RH group and - 0.43 for the LH group, p < 0.05). The rsFC within contra-lesioned M1 that innervates the normal side was weakened compared with that of normal controls (p < 0.05). Stronger rsFC of motor components in left hemisphere was confirmed by rs-fNIRS as the "secret of dominance" for the first time, while post-stroke hemiplegia broke this cortical asymmetry. Meanwhile, a statistically strengthened rsFC between left S1 and M1 only in right-hemiplegia group may act as a compensation for the impairment of the dominant side. This research has implications for brain-computer interfaces synchronizing sensory feedback with motor performance and transcranial magnetic regulation for cortical excitability to induce cortical plasticity.


Assuntos
Córtex Sensório-Motor , Acidente Vascular Cerebral , Humanos , Lateralidade Funcional/fisiologia , Hemiplegia/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Acidente Vascular Cerebral/diagnóstico por imagem , Córtex Sensório-Motor/diagnóstico por imagem , Plasticidade Neuronal/fisiologia
10.
J Virol ; 95(15): e0036121, 2021 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-33980594

RESUMO

Foot-and-mouth disease virus (FMDV) is the pathogen of foot-and-mouth disease (FMD), which is a highly contagious disease in cloven-hoofed animals. To survive in the host, FMDV has evolved multiple strategies to antagonize host innate immune responses. In this study, we showed that the leader protease (Lpro) of FMDV, a papain-like proteinase, promoted viral replication by evading the antiviral interferon response through counteracting the 2',5'-oligoadenylate synthetase (OAS)/RNase L system. Specifically, we observed that the titers of Lpro deletion virus were significantly lower than those of wild-type FMDV (FMDV-WT) in cultured cells. Our mechanistic studies demonstrated that Lpro interfered with the OAS/RNase L pathway by interacting with the N-terminal domain of swine RNase L (sRNase L). Remarkably, Lpro of FMDV exhibited species-specific binding to RNase L in that the interaction was observed only in swine cells, not human, monkey, or canine cells. Lastly, we presented evidence that by interacting with sRNase L, FMDV Lpro inhibited cellular apoptosis. Taken together, these results demonstrate a novel mechanism that Lpro utilizes to escape the OAS/RNase L-mediated antiviral defense pathway. IMPORTANCE FMDV is a picornavirus that causes a significant disease in agricultural animals. FMDV has developed diverse strategies to escape the host interferon response. Here, we show that Lpro of FMDV antagonizes the OAS/RNase L pathway, an important interferon effector pathway, by interacting with the N-terminal domain of sRNase L. Interestingly, such a virus-host interaction is species-specific because the interaction is detected only in swine cells, not in human, monkey, or canine cells. Furthermore, Lpro inhibits apoptosis through interacting with sRNase L. This study demonstrates a novel mechanism by which FMDV has evolved to inhibit host innate immune responses.


Assuntos
2',5'-Oligoadenilato Sintetase/metabolismo , Endopeptidases/metabolismo , Endorribonucleases/metabolismo , Vírus da Febre Aftosa/imunologia , Evasão da Resposta Imune/imunologia , Imunidade Inata/imunologia , Animais , Apoptose/imunologia , Linhagem Celular , Cricetinae , Cães , Endopeptidases/genética , Endopeptidases/imunologia , Endorribonucleases/genética , Febre Aftosa/imunologia , Febre Aftosa/virologia , Células HEK293 , Haplorrinos , Humanos , Evasão da Resposta Imune/genética , Células Madin Darby de Rim Canino , Domínios Proteicos , Suínos
11.
Opt Lett ; 47(11): 2927-2930, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35648966

RESUMO

We propose a sign-singularity solution in single-shot digital speckle interferometry based on vortex-phase modulation. The vortex phase is introduced through the reference beam as variation information by a reflective liquid crystal spatial light modulator. The sign singularity is eliminated with the help of a single spiral speckle fringe pattern. To effectively obtain the deformation phase, the measurement process is specially designed on the consideration of the modulation principle of the vortex phase, which is discussed in terms of theoretical analysis and simulation results. Experiments on out-of-plane deformation measurement reveal the feasibility of the proposed method and suggest the potential in actual dynamic measurement applications.

12.
Opt Lett ; 47(20): 5264-5267, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36240338

RESUMO

We propose a novel, to the best of our knowledge, single-shot quantitative phase imaging (QPI) technique with the phase modulation of a liquid crystal spatial light modulator (LC-SLM) under white light illumination. By studying the phase modulation characteristics of an LC-SLM under white light illumination, images captured at different wavelengths are equivalent to those captured at different defocus distances when loading a Fresnel lens pattern on the LC-SLM. Consequently, a color camera is able to simultaneously acquire multi-intensity images at different defocus distances. Finally, the phase is retrieved from a single-shot color image using the transport of intensity equation. To demonstrate the flexibility and accuracy of our method, a photoetched phase object and human red blood cells are quantitatively measured. An investigation of living yeast cells is conducted to verify the dynamic measurement capability. The proposed method provides a simple, efficient, and flexible means to accomplish real-time high-resolution quantitative phase imaging without sacrificing the field of view (FOV), which can be further integrated into a conventional microscope to achieve real-time microscopic QPI.


Assuntos
Iluminação , Cristais Líquidos , Humanos , Luz , Cristais Líquidos/química , Microscopia/métodos
13.
J Biol Chem ; 294(30): 11420-11432, 2019 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-31167783

RESUMO

The cyclic dinucleotide (CDN)-stimulator of interferon genes (STING) pathway plays an important role in the detection of viral and bacterial pathogens in animals. Previous studies have shown that the metazoan second messenger cyclic [G(2',5')pA(3',5')p] (2',3'-cGAMP) generated by cyclic GMP-AMP synthase cGAS binds STING with high affinity compared with bacterial CDNs such as c-di-GMP, c-di-AMP, and 3',3'-cGAMP. Despite recent progress indicating that the CDN-binding domain (CBD) of dimeric STING binds asymmetric 2',3'-cGAMP preferentially over symmetric 3',3'-CDNs, it remains an open question whether STING molecules, such as human STING, adopt a symmetric dimeric conformation to efficiently engage its asymmetric ligand. Here, structural studies of the CBD from porcine STING (STINGCBD) in complex with CDNs at 1.76-2.6 Å resolution revealed that porcine STINGCBD, unlike its human and mouse counterparts, can adopt an asymmetric ligand-binding pocket to accommodate the CDNs. We observed that the extensive interactions and shape complementarity between asymmetric 2',3'-cGAMP and the ligand-binding pocket make it the most preferred ligand for porcine STING and that geometry constraints limit the binding between symmetric 3',3'-CDN and porcine STING. The ligand-discrimination mechanism of porcine STING observed here expands our understanding of how the CDN-STING pathway is activated and of its role in antiviral defense.


Assuntos
Fosfatos de Dinucleosídeos/química , Fosfatos de Dinucleosídeos/metabolismo , Proteínas de Membrana/química , Proteínas de Membrana/metabolismo , Nucleotídeos Cíclicos/química , Nucleotídeos Cíclicos/metabolismo , Animais , Sítios de Ligação , Cristalografia por Raios X , Ligantes , Estrutura Molecular , Ligação Proteica , Suínos
14.
Fish Shellfish Immunol ; 83: 96-103, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30195915

RESUMO

Intelectin displays carbohydrate binding capacity and has been demonstrated to agglutinate bacteria, suggesting its role in innate immunity. It has also been linked to many pathogenic conditions in human. After reporting two amphioxus orthologs and the zebrafish intelectin 2 (zITLN2), here we cloned and characterized zebrafish intelectin 1 (zITLN1). Like zITLN2, zITLN1 also contains a conserved fibrinogen-related domain (FReD) and a unique intelectin domain (ITLN-D), expresses in all the tissues tested, with the highest level in intestine, and responds to bacterial challenge in acute phase. We also expressed zITLN1 in E. coli system, and purified recombinant zITLN1 could agglutinate both Gram-positive and Gram-negative bacteria in a calcium dependent manner. Its ability to agglutinate Gram-positive bacteria is stronger than that to Gram-negative bacteria whereas zITLN2 did not show such preference. This is probably due to the fact that recombinant zITLN1 could bind peptidoglycan (PGN) with a higher degree to lipopolysaccharide (LPS). Our results of zITLN1 provided new insight into the evolution and function of the intelectin family.


Assuntos
Citocinas/imunologia , Doenças dos Peixes/imunologia , Imunidade Inata , Lectinas/imunologia , Peixe-Zebra/imunologia , Aglutinação , Animais , Citocinas/genética , Escherichia coli , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Lectinas/genética , Lipopolissacarídeos , Peptidoglicano/metabolismo , Filogenia , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Staphylococcus aureus
15.
BMC Vet Res ; 14(1): 20, 2018 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-29351775

RESUMO

BACKGROUND: Pseudorabies, a highly contagious infectious disease of swine is caused by pseudorabies virus (PRV). PRV can cause fatal infection in other animal species. RESULTS: We report a deadly outbreak of pseudorabies that killed 87.2% (3522/4028) minks in a farm in 2014 in Shandong Province, China. PRV was isolated by using Vero cell culture and detected in mink samples by PCR from minks died during the outbreak. Epidemiological analysis indicated that 5.8% of minks (33/566) were PCR positive to PRV in Shandong Province. Phylogenetic analysis indicated that the PRV strains isolated from minks in this study were in the same clade with the Chinese porcine PRV isolates, which are resistant to the PRV vaccine. CONCLUSIONS: We demonstrated that pseudorabies virus caused an outbreak of minks in a farm in Shandong Province of China and the virus has a very high infection rate in minks in Shandong Province, which is a challenge for the fur industry in China.


Assuntos
Surtos de Doenças/veterinária , Herpesvirus Suídeo 1/isolamento & purificação , Vison/virologia , Pseudorraiva/epidemiologia , Animais , China/epidemiologia , Chlorocebus aethiops , Herpesvirus Suídeo 1/classificação , Herpesvirus Suídeo 1/genética , Filogenia , Reação em Cadeia da Polimerase/veterinária , Pseudorraiva/mortalidade , Pseudorraiva/virologia , Análise de Sequência de DNA , Células Vero
16.
Nano Lett ; 17(8): 4831-4839, 2017 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-28661680

RESUMO

Organic-inorganic hybrid perovskites have shown great potential as building blocks for low-cost optoelectronics for their exceptional optical and electrical properties. Despite the remarkable progress in device demonstration, fundamental understanding of the physical processes in halide perovskites remains limited, especially the unusual electronic behaviors such as the current-voltage hysteresis and the switchable photovoltaic effect. These phenomena are of particular interests for being closely related to device functionalities and performance. In this work, a microscopic picture of electric fields in halide perovskite thin films was obtained using scanning laser microscopy. Unlike conventional semiconductors, distribution of the built-in electric fields in the halide perovskite evolves dynamically under the stimulation of external biases. The observations can be well explained using a model based on field-assisted ion migration, indicating that the mechanism responsible for the evolving charge transport observed in this material is not purely electronic. The anomalous dynamic responses to the applied bias are found to be effectively suppressed by operating the devices at reduced temperature or processing the materials at elevated temperature, which provide potential strategies for designing and creating halide perovskites with more stable charge transport properties in the development of viable perovskite-based optoelectronics.

17.
Microb Pathog ; 109: 319-324, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28457899

RESUMO

Porcine reproductive and respiratory syndrome (PRRS), a highly contagious disease, has been constantly causing huge economic losses all over the world. PRRS virus (PRRSV) infection results in immunosuppression and IL-10 up-regulation. The relationship between them is still in dispute. Previous studies demonstrated the protein of PRRSV nucleocapsid (N) protein is able to up-regulate IL-10, yet the underlying molecular mechanisms remain unknown. In this study, the expression kinetics of IL-10 up-regulation induced by PRRSV N protein were analyzed in immortalized porcine alveolar macrophages (PAMs). N protein induced IL-10 expression in a time- and dose-dependent manner. Inhibition experiments of signaling pathways suggested NF-κB and p38 MAPK pathways are both involved in N protein-induced IL-10 up-regulation. Besides, the integrity of N protein is essential for significant IL-10 up-regulation. This research is beneficial for further understanding of the interplay between PRRSV and host immune system.


Assuntos
Interleucina-10/metabolismo , Macrófagos Alveolares/imunologia , NF-kappa B/metabolismo , Proteínas do Nucleocapsídeo/metabolismo , Vírus da Síndrome Respiratória e Reprodutiva Suína/metabolismo , Suínos/imunologia , Regulação para Cima , Animais , Linhagem Celular , Regulação da Expressão Gênica , Terapia de Imunossupressão , Macrófagos Alveolares/virologia , Proteínas do Nucleocapsídeo/genética , Síndrome Respiratória e Reprodutiva Suína/imunologia , Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Vírus da Síndrome Respiratória e Reprodutiva Suína/imunologia , Transdução de Sinais , Suínos/virologia , Proteínas Virais/genética , Proteínas Virais/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
18.
Virol J ; 13(1): 185, 2016 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-27842600

RESUMO

BACKGROUND: This study aimed at reseaching the immune effect of porcine circovirus type 2 (PCV2) DNA vaccine containing CpG motif on mice. METHODS: A total of 40 6-week-old female BALB/c mice were randomly divided into four groups which were immunized by 18CpG-pVAX1-ORF2, pVAX1-ORF2, pVAX1 and PBS, respectively, and immunized again 2 weeks later. All mice were challenged with 0.2 mL PCV2 cells virulent strain SD (106.0 TCID50/mL) after 4 weeks. Average daily gain, blood antibody levels, microscopic changes and viremia were detected to estimate the effect of DNA vaccine. RESULTS AND DISCUSSION: The results showed that compared to those of the control mice, groups immunized with pVAX1-ORF2 and 18CpG-pVAX1-ORF2 could induce PCV2-specific antibodies. The PCV2-specific antibodies level of 18 CpG-pVAX1-ORF2 groups was higher significantly than other groups and decreased slowly along with time. There was no distinct pathological damage and viremia occurring in mice that inoculated with CpG motif DNA vaccines. The results demonstrated that the DNA vaccine containing 18 CpG could build up resistibility immunity and reduce immune organ damage on mice.


Assuntos
Adjuvantes Imunológicos , Infecções por Circoviridae/prevenção & controle , Circovirus/imunologia , Ilhas de CpG , Vacinas de DNA/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Antivirais/sangue , Peso Corporal , Infecções por Circoviridae/patologia , Modelos Animais de Doenças , Feminino , Esquemas de Imunização , Camundongos Endogâmicos BALB C , Resultado do Tratamento , Vacinas de DNA/administração & dosagem , Vacinas de DNA/genética , Vacinas Virais/administração & dosagem , Vacinas Virais/genética , Viremia/prevenção & controle
19.
Mol Cell Probes ; 30(2): 83-92, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26828953

RESUMO

Porcine reproductive and respiratory syndrome virus (PRRSV) heavily affects the global pork industry. Current available vaccine strategies have inherent drawbacks. In this work, the immune enhancement from Taishan Pinus massoniana pollen polysaccharide (TPPPS) and Freund's adjuvant on the efficacy of a PRRSV subunit vaccine were examined. Titers of specific anti-highly pathogenic PRRSV (HP-PRRSV) ELISA antibody and neutralizing antibody were significantly higher in pigs from the groups inoculated with medium- and high-dose TPPPS (mTPPPS, hTPPPS) adjuvant co-administered with a recombinant HP-PRRSV glycoprotein 5 subunit (GP5) than those from other groups (P < 0.05). Pigs inoculated with GP5 + Freund's adjuvant developed severely delayed humoral immune responses specific to GP5 within 28 days post-inoculation (dpi). The groups treated with mTPPPS and hTPPPS adjuvant exhibited the most potent immune enhancement effects on GP5 inoculation with cellular immunity developing, as shown by the level of T lymphocyte proliferation and the percentage of the CD3(+) T lymphocyte subpopulation. Although complete Freund's adjuvant elicited cell-mediated immune responses, the level of T lymphocyte proliferation in this group decreased quickly and no significant differences were observed compared with other adjuvant-alone groups at 56 dpi (P > 0.05). The ratio between CD3(+)CD4(+) and CD3(+)CD8(+) T lymphocyte subpopulations indicated the inoculums of GP5 + mTPPPS and GP5 + hTPPPS induced consistently higher CD3(+)CD4(+) T lymphocyte subpopulations than other inoculums (P < 0.05). The immune responses caused by complete Freund's adjuvant were mainly mediated by CD3(+)CD8(+) T lymphocyte subpopulation (cytotoxic T lymphocytes) in the early stage of inoculation and had no significant difference compared with other adjuvant-alone groups after 28 dpi (P > 0.05). The low-dose TPPPS (lTPPPS) adjuvant also exhibited enhancement effects on humoral immune and T lymphocyte proliferation responses but these were significantly lower than the mTPPPS and hTPPPS doses (P < 0.05). Pigs challenged with HP-PRRSV from the GP5 + mTPPPS, GP5 + hTPPPS, and GP5 + Freund's adjuvant groups showed lower viremia, fewer clinical signs, and fewer pathological lung lesions compared with the groups of GP5-alone and GP5 + lTPPPS (P < 0.05). There were significant differences between the GP5-alone and GP5 + lTPPPS groups in detection indexes after viral challenge (P < 0.05). In conclusion, moderate doses of TPPPS as an adjuvant with GP5 show promise as a candidate for a HP-PRRSV subunit vaccine to efficiently prevent and control HP-PRRSV.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Pinus/química , Pólen/química , Polissacarídeos/administração & dosagem , Síndrome Respiratória e Reprodutiva Suína/prevenção & controle , Adjuvantes Imunológicos/farmacologia , Animais , Anticorpos Antivirais/metabolismo , Polissacarídeos/imunologia , Polissacarídeos/farmacologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/patogenicidade , Suínos , Proteínas do Envelope Viral/imunologia , Vacinas Virais/administração & dosagem
20.
Fish Shellfish Immunol ; 55: 729-36, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27329687

RESUMO

Intelectins are glycan-binding lectins found in various species including cephalochordates, urochordates, fish, amphibians and mammals. But their detailed functions are not well studied in zebrafish which is a good model to study native immunity. In this study, we cloned a zebrafish intelectin ortholog, zebrafish intelectin 2 (zITLN2), which contains a conserved fibrinogen-related domain (FReD) in the N-terminus and the unique intelectin domain in the C-terminus. We examined the tissue distribution of zITLN2 in adult zebrafish and found that zITLN2 was expressed in various organs with the highest level in intestine. Like amphioxus intelectins, zITLN2 expression was upregulated in adult zebrafish infected with Staphylococcus aureus with the highest expression level at 12 h after challenge. Recombinant zITLN2 protein expressed in E. coli was able to agglutinate both Gram-negative and Gram-positive bacteria to similar degrees in a calcium-dependent manner. Furthermore, recombinant zITLN2 bound lipopolysaccharide (LPS) and peptidoglycan (PGN) comparably. Our work on zITLN2 provided further information to understand functions of this new family of lectins and the innate immunity in vertebrates.


Assuntos
Infecções por Escherichia coli/veterinária , Doenças dos Peixes/genética , Lectinas/genética , Infecções Estafilocócicas/veterinária , Proteínas de Peixe-Zebra/genética , Peixe-Zebra , Sequência de Aminoácidos , Animais , Escherichia coli/fisiologia , Infecções por Escherichia coli/genética , Infecções por Escherichia coli/imunologia , Infecções por Escherichia coli/metabolismo , Doenças dos Peixes/imunologia , Doenças dos Peixes/metabolismo , Lectinas/química , Lectinas/metabolismo , Lipopolissacarídeos/metabolismo , Peptidoglicano/metabolismo , Alinhamento de Sequência/veterinária , Infecções Estafilocócicas/genética , Infecções Estafilocócicas/imunologia , Infecções Estafilocócicas/metabolismo , Staphylococcus aureus/fisiologia , Proteínas de Peixe-Zebra/química , Proteínas de Peixe-Zebra/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA