The proportion of human isolates with reduced neuraminidase inhibitors (NAIs) susceptibility in highly pathogenic avian influenza (HPAI) H7N9 virus was high. These drug-resistant strains showed good replication capacity without serious loss of fitness. In the presence of oseltamivir, R229I substitution were found in HA1 region of the HPAI H7N9 virus before NA R292K appeared.
View Article and Find Full Text PDFBackground: Ineffective effort (IE) is a frequent patient-ventilator asynchrony in invasive mechanical ventilation. This study aimed to investigate the incidence of IE and to explore its relationship with respiratory drive in subjects with acute brain injury undergoing invasive mechanical ventilation.
Methods: We retrospectively analyzed a clinical database that assessed patient-ventilator asynchrony in subjects with acute brain injury.
Experimentally, certain cells in the brain exhibit a spike-burst activity with burst synchronization at transition to and during sleep (or drowsiness), while they demonstrate a desynchronized tonic activity in the waking state. We herein investigated the neural activities and their transitions by using a model of coupled Hindmarsh-Rose neurons in an Erdős-Rényi random network. By tuning synaptic strength, spontaneous transitions between tonic and bursting neural activities can be realized.
View Article and Find Full Text PDFObjective: In China, 24 cases of human infection with highly pathogenic avian influenza (HPAI) H5N6 virus have been confirmed since the first confirmed case in 2014. Therefore, we developed and assessed two H5N6 candidate vaccine viruses (CVVs).
Methods: In accordance with the World Health Organization (WHO) recommendations, we constructed two reassortant viruses using reverse genetics (RG) technology to match the two different epidemic H5N6 viruses.
Human infections with highly pathogenic avian influenza (HPAI) H7N9 virus were detected in late 2016. We examined the drug resistance profile of 30 HPAI H7N9 isolates from Mainland of China (2016-2019). Altogether, 23% (7/30) carried neuraminidase inhibitors (NAIs) - resistance mutations, and 13% (4/30) displayed reduced susceptibility to NAIs in neuraminidase (NA) inhibition test.
View Article and Find Full Text PDFObjective: To recover broad-neutralizing monoclonal antibodies (BnAbs) from avian influenza A (H5N1) virus infection cases and investigate their genetic and functional features.
Methods: We screened the Abs repertoires of expanded B cells circulating in the peripheral blood of H5N1 patients. The genetic basis, biological functions, and epitopes of the obtained BnAbs were assessed and modeled.
In the course of development, sleep, or mental disorders, certain neurons in the brain display spontaneous spike-burst activity. The synaptic plasticity evoked by such activity is here studied in the presence of spike-timing-dependent plasticity (STDP). In two chemically coupled bursting model neurons, the spike-burst activity can translate the STDP related to pre- and postsynaptic spike activity into burst-timing-dependent plasticity (BTDP), based on the timing of bursts of pre- and postsynaptic neurons.
View Article and Find Full Text PDFIn real-world networked systems, the underlying structure is often affected by external and internal unforeseen factors, making its evolution typically inaccessible. An adaptive strategy was introduced for maintaining synchronization on unpredictably evolving networks [Sorrentino and Ott, Phys. Rev.
View Article and Find Full Text PDFMicrosaccades are involuntary and very small eye movements during fixation. Recently, the microsaccade-related neural dynamics have been extensively investigated both in experiments and by constructing neural network models. Experimentally, microsaccades also exhibit many behavioral properties.
View Article and Find Full Text PDFObjective: To investigate the changes in lymphocyte subsets that are caused by infection with different pathogens in children with hand, foot, and mouth disease.
Methods: T lymphocyte subsets were measured in the patients' peripheral blood, and serum, throat swab, and fecal samples were tested for enterovirus.
Results: Fecal and throat swab samples exhibited similar positive detection rates, and were significantly more likely to be positive, compared to serum samples (P < 0.
Microsaccades are very small eye movements during fixation. Experimentally, they have been found to play an important role in visual information processing. However, neural responses induced by microsaccades are not yet well understood and are rarely studied theoretically.
View Article and Find Full Text PDFRecently, the significant microsaccade-induced neural responses have been extensively observed in experiments. To explore the underlying mechanisms of the observed neural responses, a feedforward network model with short-term synaptic depression has been proposed [Yuan, W.-J.
View Article and Find Full Text PDFFragments encoding amino acids 76-130 in the linear conserved region (LCR) of A/Hubei/1/2010 (H5N1) HA2 was fused to hepatitis B core antigen (HBc) to generate a LCR-HBe virus-like particle (VLP). Results showed that the fusion protein of LCR-HBc was highly expressed in this prokaryotic expression system. The purified LCR-HBc particle stimulated high levels of IgG production in mice with a titer of > 1:12 800, and provided 50% cross-protection against lethal challenge by H1N1 viruses.
View Article and Find Full Text PDFVaccination is the primary strategy for the prevention and control of pandemic influenza. Because influenza virus is highly variable across strains, universal influenza vaccines need to be developed to address this problem. This review describes the research progress in conserved epitopes of influenza virus, the advances in the research and development of universal influenza vaccines based on the relatively conserved sequences of NP, M2e, HA2, and headless HA, the mechanisms of cross-protection, and the methods to improve cross-protection.
View Article and Find Full Text PDFIn sensory neural system, external asynchronous stimuli play an important role in perceptual learning, associative memory and map development. However, the organization of structure and dynamics of neural networks induced by external asynchronous stimuli are not well understood. Spike-timing-dependent plasticity (STDP) is a typical synaptic plasticity that has been extensively found in the sensory systems and that has received much theoretical attention.
View Article and Find Full Text PDFPhys Rev E Stat Nonlin Soft Matter Phys
August 2013
Inspired by the anti-Hebbian learning rule in neural systems, we study how the feedback from dynamical synchronization shapes network structure by adding new links. Through extensive numerical simulations, we find that an adaptive network spontaneously forms scale-free structure, as confirmed in many real systems. Moreover, the adaptive process produces two nontrivial power-law behaviors of deviation strength from mean activity of the network and negative degree correlation, which exists widely in technological and biological networks.
View Article and Find Full Text PDFNucleoprotein (NP) of influenza virus is highly conserved and type-specific. NP can trigger strong cell-mediated immune responses in host and is involved in the protection against the challenges with different subtype influenza viruses. Here, NP of an avian H5N1 (A/Hubei/1/2010, HB) was expressed by baculovirus surface-display technology and its immunogenicity as well as protective mechanism was investigated in mice infection model.
View Article and Find Full Text PDFZhonghua Shi Yan He Lin Chuang Bing Du Xue Za Zhi
February 2013
Objective: To understand if the Neuraminidase (N1) of Influenza A virus at the surface of yeast-displaying system, eukaryotic expression system and the infected cells could be used for anti-NA Abs screening, their activities and bindings to five candidate Abs were assayed.
Methods: The surface NA expression was obtained by transfecting by recombinant NA constructors with specific tag-labels or live virus infection. The functional activity was measured by the fluorescent assay.
Bing Du Xue Bao
September 2012
Influenza viruses are highly contagious for human population and result in acute respiratory infectious diseases ranging from mild to severe. Neuraminidase (NA) inhibitors (NAIs) (oseltamivir, zanamivir, peramivir and laninamivir), which target the NA glycoproteins of influenza A and B viruses are widely used in the prophylaxis and treatment of influenza virus infection. However, the substitutions of amino acids in NA or HA gene may lead to resistances to NAIs.
View Article and Find Full Text PDFIntroduction: Left ventricular (LV) dysfunction is common in septic shock. Its association with the clinical outcome is still controversial. Tissue Doppler imaging (TDI) is a useful tool to quantify LV function; however, little knowledge is available about the prognostic value of these TDI variables in septic shock.
View Article and Find Full Text PDFBiomed Environ Sci
February 2012
Objective: Both the 2, 6 linkage and its topology on target cells are critical for the recognition by human influenza virus. The binding preference of avian flu virus H5N1 HA to the 2, 3-linked sialylated glycans is considered the major factor limiting its efficient infection and transmission in humans. To monitor potential adaptation of H5N1 virus in human population, the surveillance of receptor-binding specificity was undertaken in China.
View Article and Find Full Text PDFThis study aimed to develop an effective experimental vaccine against highly pathogenic H5N1 Avian Influenza (HPAI) virus and to optimize their immunization programs. As reported previously, various DNA-based or recombinant vaccinia viral(Tiantan)-based H5N1 vaccine candidates, which containing a single cistronic construct (HAop, or NAop) or a bicistronic construct (HAop/M2 or NAop/M1) of H5N1 influenza virus (Anhui strain) were constructed and characterized in our lab. In this study, we further analysed the immunogenicity in mice of these vaccine candidates by various protocols (single or combined immunization).
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