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1.
Adv Mater ; 36(23): e2400655, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38373742

RESUMO

Ultrathin 2D ferroelectrics with high Curie temperature are critical for multifunctional ferroelectric devices. However, the ferroelectric spontaneous polarization is consistently broken by the strong thermal fluctuations at high temperature, resulting in the rare discovery of high-temperature ferroelectricity in 2D materials. Here, a chemical vapor deposition method is reported to synthesize 2D CuCrSe2 nanosheets. The crystal structure is confirmed by scanning transmission electron microscopy characterization. The measured ferroelectric phase transition temperature of ultrathin CuCrSe2 is about ≈800 K. Significantly, the switchable ferroelectric polarization is observed in ≈5.2 nm nanosheet. Moreover, the in-plane and out-of-plane ferroelectric response are modulated by different maximum bias voltage. This work provides a new insight into the construction of 2D ferroelectrics with high Curie temperature.

2.
Biologicals ; 60: 36-41, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31178277

RESUMO

JE vaccination is the most effective and economical method of preventing JE. A live attenuated JE vaccine has been widely used in many countries since 1989, playing an important role in controlling JE outbreaks. However, whether the large-scale use of the live attenuated JE vaccine will lead to the dissemination of the vaccine virus in the environment and whether reversion of the neuroattenuation of the virus will occur during the transmission process remain major concerns for some researchers. To evaluate the transmission of a live attenuated JEV vaccine in mosquitoes and hosts, JE SA14-14-2 attenuated vaccine virus was intrathoracically (i.t.) inoculated into Culex tritaeniorhynchus, a native vector. Subsequently, virus harvested from inoculated mosquitoes was inoculated into pigs, a mammalian reservoir. The virus was isolated from the pigs and passaged once again in Culex tritaeniorhynchus. The genome sequences and virulence of the passaged viruses were then investigated. While a few nucleotide substitutions occurred during passaging, there was no change in the encoded amino acids. After intracerebral (i.c.) inoculation of mice with the vaccine, no pathological effects were observed. In addition, virus virulence remained low after inoculation of suckling mouse brains. These results indicate that vaccination of individuals with the live vaccine will not result in transmission of the live SA14-14-2 vaccine virus through mosquito biting and virus amplified in pigs.


Assuntos
Vírus da Encefalite Japonesa (Espécie)/imunologia , Encefalite Japonesa , Vacinas contra Encefalite Japonesa/imunologia , Animais , Linhagem Celular , Cricetinae , Culex/imunologia , Culex/virologia , Encefalite Japonesa/imunologia , Encefalite Japonesa/prevenção & controle , Feminino , Vacinas contra Encefalite Japonesa/efeitos adversos , Masculino , Camundongos , Suínos , Vacinas Atenuadas
3.
Sensors (Basel) ; 19(3)2019 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-30699946

RESUMO

Successful applications of brain-computer interface (BCI) approaches to motor imagery (MI) are still limited. In this paper, we propose a classification framework for MI electroencephalogram (EEG) signals that combines a convolutional neural network (CNN) architecture with a variational autoencoder (VAE) for classification. The decoder of the VAE generates a Gaussian distribution, so it can be used to fit the Gaussian distribution of EEG signals. A new representation of input was developed by combining the time, frequency, and channel information from the EEG signal, and the CNN-VAE method was designed and optimized accordingly for this form of input. In this network, the classification of the extracted CNN features is performed via the deep network VAE. Our framework, with an average kappa value of 0.564, outperforms the best classification method in the literature for BCI Competition IV dataset 2b with a 3% improvement. Furthermore, using our own dataset, the CNN-VAE framework also yields the best performance for both three-electrode and five-electrode EEGs and achieves the best average kappa values 0.568 and 0.603, respectively. Our results show that the proposed CNN-VAE method raises performance to the current state of the art.

5.
Vaccine ; 36(31): 4650-4656, 2018 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-29954631

RESUMO

Japanese encephalitis (JE) live attenuated vaccine SA14-14-2 is the most widely used JE vaccine in the world. Large-scale clinical trials have demonstrated satisfactory safety and efficacy profiles. The establishment of genetic and attenuated neurovirulence characteristics and their stabilities of SA14-14-2 virus are important in relation to vaccine safety in humans. Therefore, several researchers have studied and analyzed the full-length gene sequences of the SA14-14-2 virus strain. However, sequencing results have shown a significant difference. Here, we further studied the full-length sequence of three class seed virus banks of the vaccine as well as two vaccine viruses with different passages in primary hamster kidney cells, and compared them with our original stored SA14 parent virus (low passage in mouse brain). The full-length gene sequence determined in this study indicates there were 57 nucleotide and 25 amino acid substitutions of the SA14-14-2 strain compared to its parental SA14 virus strain. The full-length sequences of the three class seed bank viruses and the vaccine virus PHKC8 were completely identical among them, but the working seed virus passaged in primary hamster kidney cells for 17 generations (PHKC17) had a single nucleotide change at the 5' NCR. Both KM and ICR mice tested by intracerebral (i.c.) or subcutaneous (s.c.) routes with the three class seed viruses and vaccine viruses with ≥5.7 lgpfu/mL remained healthy, but all the mice inoculated with the SA14 parental virus strain died as early as day 5 post-inoculation. The present study provided new information on the full-length gene sequence and attenuated neurovirulence of SA14-14-2. They can be used as a reference sequence for vaccine quality control and surveillance of neurovirulence reversion following vaccination. Moreover, the present results further demonstrated the high genetic and phenotypic stabilities of the SA14-14-2 virus, suggesting the neurovirulence reversion of the vaccine strain will be highly unlikely.


Assuntos
Vacinas contra Encefalite Japonesa/efeitos adversos , Vacinas contra Encefalite Japonesa/imunologia , Substituição de Aminoácidos , Animais , Células Cultivadas , Cricetinae , Análise Mutacional de DNA , Estabilidade de Medicamentos , Vírus da Encefalite Japonesa (Espécie)/genética , Vírus da Encefalite Japonesa (Espécie)/crescimento & desenvolvimento , Vírus da Encefalite Japonesa (Espécie)/patogenicidade , Variação Genética , Instabilidade Genômica , Vacinas contra Encefalite Japonesa/genética , Vacinas contra Encefalite Japonesa/isolamento & purificação , Camundongos Endogâmicos ICR , Mutação Puntual , Análise de Sequência de DNA , Inoculações Seriadas , Análise de Sobrevida , Vacinas Atenuadas/efeitos adversos , Vacinas Atenuadas/genética , Vacinas Atenuadas/imunologia , Vacinas Atenuadas/isolamento & purificação , Virulência , Cultura de Vírus , Sequenciamento Completo do Genoma
6.
Zhonghua Yi Xue Za Zhi ; 91(28): 1977-81, 2011 Jul 26.
Artigo em Chinês | MEDLINE | ID: mdl-22093894

RESUMO

OBJECTIVE: To evaluate the safety of enterovirus type 71 (EV71) inactivated vaccine (human diploid derived) for infection prevention in an animal model by investigating the immune responses and related patho-inflammatory reactions. METHODS: In the neonatal monkey model for EV71 vaccine protection, vaccinated group (n = 4) and unvaccinated group (n = 4) were attacked with live virus at the same time, the parameters of clinical observations, antibodies and inflammatory factors in peripheral blood and cerebrospinal fluid (CSF) were detected. And the pathological changes in major organs were used to determine the patho-inflammatory reactions during the immune responses elicited by vaccination. RESULTS: The neutralizing antibodies of vaccine group reach to 1:32. There was no obvious changes of inflammatory factors in peripheral blood and CSF of monkeys challenged or unchallenged by live virus. In peripheral blood of unvaccinated group, the level of basophilic granulocyte higher 4 - 5 times than normal level and the interferon-γ (IFN-γ) showed obvious increase. Live virus infected after 7 days, the interleukin-6 (IL-6) and IFN-γ in peripheral blood of unvaccinated group (18.5, 12.7 pg/ml) were higher than vaccinated group (10.2, 7.6 pg/ml). Furthermore, the IL-6 in CSF (102.0 pg/ml) had 4 - 5 times increased than vaccinated group (12.4 pg/ml) at 7 days after virus exposure. Meanwhile, the pathological analysis revealed that no obvious changes were detected in CNS and other organs of vaccinated monkeys challenged with live virus. However, the pathological damages induced by virus infection could be determined in the unvaccinated control monkeys, including neuronal damage, massive cellular infiltration associated with pulmonary edema/hemorrhage and pulmonary/bronchial damage due to an infiltration of inflammatory cells. CONCLUSION: Capable of inducing an immune response, the EV71 inactivated vaccine offers protection to neonatal rhesus monkeys against the attacks of live virus. Based on the results of no patho-inflammatory reaction and pathological damage after viral infection in vaccinated animals, the excellent safety of this vaccine may be confirmed in neonatal monkey.


Assuntos
Enterovirus Humano A/imunologia , Infecções por Enterovirus/prevenção & controle , Inflamação/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Antivirais/sangue , Infecções por Enterovirus/imunologia , Imunidade , Interferon gama/metabolismo , Interleucina-6/líquido cefalorraquidiano , Macaca mulatta , Vacinação , Vacinas de Produtos Inativados/imunologia
7.
Zhonghua Yi Xue Za Zhi ; 90(16): 1141-4, 2010 Apr 27.
Artigo em Chinês | MEDLINE | ID: mdl-20646436

RESUMO

OBJECTIVE: To analyze the genetic and biological characters of a new isolate of coxsackievirus B3 (CoxB3), i.e. FY-19 strain, and investigate its mechanistic role in causing different clinical symptoms of hand-foot-mouth disease (HFMD). METHODS: FY-19 strain, isolated from a patient with severe clinical symptoms from Fuyang, China in 2008, was identified by the serological parameters via the Lim Benyesh-Melnick (LBM) antiserum pools. Its genotype was further characterized by sequencing the whole genome. And its biological characters were also examined by proliferation kinetic and pathogenetic analysis. RESULTS: FY-19 strain was identified as CoxB3 showing 23.0%, 16.5% and 32.1% difference with Nancy strain in 3'-, 5'-noncoding and coding regions respectively. FY-19 also showed a high homology with other HFMD-related CoxB3 isolates in China. But its homology with non-HFMD-related CoxB3 isolates was lower (13.5% and 25.0% difference in 3'-NCR and coding region respectively). The viral replication kinetic analysis suggested that the FY-19 proliferation increased rapidly and peaked at 14 hours post-infection. In pathological analysis, FY-19 strain induced mortal pathology in sucking mice. CONCLUSION: Differences in genetic and biological characters exist between FY-19 and Nancy strains. Further analysis on the pathogenesis of this variant may aid in elucidating the mechanisms of HFMD.


Assuntos
Enterovirus Humano B/classificação , Enterovirus Humano B/genética , Doença de Mão, Pé e Boca/virologia , Animais , Linhagem Celular , Chlorocebus aethiops , Infecções por Coxsackievirus , Enterovirus Humano B/isolamento & purificação , Genótipo , Humanos , Camundongos , RNA Viral , Células Vero , Proteínas Virais/genética
8.
Virol Sin ; 25(6): 417-24, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21221920

RESUMO

The protein HTRP (human transcription regulator protein) is encoded by the differential gene htrp and induced by Herpes simplex virus type 1 (HSV-1) infection in KMB-17 cells. HTRP was found to interact with SAP30 (mSin3A Association Protein), one of the components of co-repressor complex mSin3A, which is part of the deacetylation transfer enzyme HDAC. To reveal the biological significance of the interaction between HTRP and SAP30, real- time PCR and a dual-luciferase detecting system was used. The results indicate that HTRP could inhibit the transcription of a viral promoter, whose interaction with SAP30 synergistically affects transcriptional inhibition of the viral genes, and is related to HDAC enzyme activity. ChIP experiments demonstrate that HTRP could promote HDAC activity by increasing the deacetylation level of lysine 14 and lysine 9 in histone H3.


Assuntos
Regulação da Expressão Gênica , Herpesvirus Humano 1/patogenicidade , Proteínas Nucleares/metabolismo , Fatores de Transcrição/metabolismo , Acetilação , Linhagem Celular , Genes Reporter , Histona Desacetilases/metabolismo , Humanos , Luciferases/genética , Luciferases/metabolismo , Reação em Cadeia da Polimerase , Ligação Proteica
9.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-262104

RESUMO

<p><b>OBJECTIVE</b>To study the clinical curative effect of the new Bian-stone therapy.</p><p><b>METHODS</b>According to clinical trail principle of multi-centers, randomized grouping, parallel control and single-blind, the observation group (n=120) were treated by the new Bian-stone therapy, with multi-functional Bian-stone respectively dredging qi and blood of channels on the neck and shoulder, the shoulder and back, the limbs, and the control group (n=120) by electroacupuncture with Jianyu (LI 15), Jianliao (SJ 14), Jianzhen (SI 9), and other points selected. Their therapeutic effects were compared.</p><p><b>RESULTS</b>The two therapies had effects of analgesia, improving functional activity and transient analgesia. The total effective rate of the analgesic effect was 86.8% in the observation group and 72.5% in the control group with a significant difference between the two groups (P < 0.05), the observation group being better than the control group; the total effective rate of shoulder functional activity was 86.8% in the observation group and 79.8% in the control group with no significant difference between the two groups (P > 0.05).</p><p><b>CONCLUSION</b>The new Bian-stone therapy has obvious therapeutic effect on scapulohumeral periarthritis, with effects of analgesia, improving functional activity, and transient analgesia, and good long-term therapeutic effect.</p>


Assuntos
Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Eletroacupuntura , Medicina Tradicional Chinesa , Periartrite , Terapêutica , Dor de Ombro , Terapêutica , Método Simples-Cego
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