Search

Hepatitis C virus (HCV) infection remains a serious public health burden around the world. So far there is no effective vaccine against this virus. Neutralizing antibody (NAb) responses to the epitopes within HCV E1 and E2 proteins are related to the resolution of hepatitis C infection. E. coli heat-labile enterotoxin B subunit (LTB) has been described as potent immunity adjuvants. In this study, we constructed recombinant pET vectors: pET-R9-Bp (B cell polyepitopes) expressing 7 epitopes from HCV E1 and E2 proteins including R9 (E2

Background Porcine epidemic diarrhea virus (PEDV) is an enveloped positive-sense ssRNA virus which is highly lethal to piglets, causing enormous economic losses to swine industry worldwide. Nsp15 protein is an endoribonuclease of PEDV and plays an indispensable role in the viral proliferation. We reported the transcription files of nsp15 transfected IPEC-J2 cells for the first time to broaden our understanding of PEDV pathogenesis. Methods RNA-seq was performed to compare gene expression profiles between pCAGGS-HA-nsp15 transfected IPEC-J2 cells and pCAGGS-HA (empty vector) transfected IPEC-J2 cells. Immune-related genes and pathways were identified and analyzed to deepen our understanding of nsp15 for PEDV pathogenicity. IPEC-J2 cells transfected with pCAGGS-HA-CCL5/CXCL8/CXCL10 were infected with CV777 and the virus load of PEDV was detected by qRT-PCR. Results A total of 21,654 genes were obtained by RNA-Seq and 415 differential expressed genes (DEGs) were identified, including 136 up-regulated and 279 down-regulated genes. A number of effect genes involved in immune responses and inflammation were differentially expressed. GO and KEGG enrichment analysis showed that 32 GO terms were significantly enriched and the DEGs were mainly enriched in immune-related pathways such as TNF signaling pathway, RIG-I-like receptor signaling pathway and Cytosolic DNA-sensing pathway. qRT-PCR results indicated the overexpression of selected chemokines, CCL5/CXCL8/CXCL10, can inhibit PEDV proliferation in IPEC-J2 cells. Conclusions Our transcriptome profile illustrated a number of genes involving in immune responses and inflammation were inhibited by nsp15, such as CCL5, CXCL8, CXCL10, OAS, MXs, STAT1 and IRF9. The results suggested that nsp15 can antagonize IFNs and block chemokine system to provide an adequate intracellular environment for viral proliferation.

Hepatitis C virus (HCV) nonstructural protein NS4B is necessary for HCV replication. Our previous research found that NS4B-associated cellular proteins PREB and Surfeit 4 are involved in HCV replication. However, the molecular mechanism of HCV replication is not fully understood. Here we identified cellular ovarian cancer immunoreactive antigen domain containing 2 (OCIAD2) protein as a novel NS4B-associated HCV host cofactor by screening with small interfering RNA. Knockdown of OCIAD2 reduced significantly the HCV replication in a dose-dependent and genotype-independent manner. Further research showed that OCIAD2 was recruited into the HCV RNA replication complex by the interaction with NS4B. Interestingly, HCV replication induced OCIAD2 expression. In turn, overexpression of wild OCIAD2 also promoted virus replication whereas that of OCIAD2 mutant lacking the ability to bind NS4B exerted no effect on HCV replication. We also examined whether OCIAD2 interacted with other proteins participating in the HCV RNA replication complex including viral proteins NS5A, NS5B, and cellular proteins PREB, Surfeit 4. The results showed that OCIAD2 interacted with PREB and NS5A, but not NS5B or Surfeit 4. Our findings provide new insights into the function of OCIAD2 and HCV replication mechanism.

A number of positive-strand RNA viruses, such as hepatitis C virus (HCV) and poliovirus, use double-membrane vesicles (DMVs) as replication sites. However, the role of cellular proteins in DMV formation during virus replication is poorly understood. HCV NS4B protein induces the formation of a “membranous web” structure that provides a platform for the assembly of viral replication complexes. Our previous screen of NS4B-associated host membrane proteins by dual-affinity purification, liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS), and small interfering RNA (siRNA) methods revealed that the Surfeit 4 (Surf4) gene, which encodes an integral membrane protein, is involved in the replication of the JFH1 subgenomic replicon. Here, we investigated in detail the effect of Surf4 on HCV replication. Surf4 affects HCV replication in a genotype-independent manner, whereas HCV replication does not alter Surf4 expression. The influence of Surf4 on HCV replication indicates that while Surf4 regulates replication, it has no effect on entry, translation, assembly, or release. Analysis of the underlying mechanism showed that Surf4 is recruited into HCV RNA replication complexes by NS4B and is involved in the formation of DMVs and the structural integrity of RNA replication complexes. Surf4 also participates in the replication of poliovirus, which uses DMVs as replication sites, but it has no effect on the replication of dengue virus, which uses invaginated/sphere-type vesicles as replication sites. These findings clearly show that Surf4 is a novel cofactor that is involved in the replication of positive-strand RNA viruses using DMVs as RNA replication sites, which provides valuable clues for DMV formation during positive-strand RNA virus replication. IMPORTANCE Hepatitis C virus (HCV) NS4B protein induces the formation of a membranous web (MW) structure that provides a platform for the assembly of viral replication complexes. The main constituents of the MW are double-membrane vesicles (DMVs). Here, we found that the cellular protein Surf4, which maintains endoplasmic reticulum (ER)-Golgi intermediate compartments and the Golgi compartment, is recruited into HCV RNA replication complexes by NS4B and is involved in the formation of DMVs. Moreover, Surf4 participates in the replication of poliovirus, which uses DMVs as replication sites, but has no effect on the replication of dengue virus, which uses invaginated vesicles as replication sites. These results indicate that the cellular protein Surf4 is involved in the replication of positive-strand RNA viruses that use DMVs as RNA replication sites, providing new insights into DMV formation during virus replication and potential targets for the diagnosis and treatment of positive-strand RNA viruses.

Accumulated evidence demonstrates that Japanese encephalitis virus (JEV) infection triggers endoplasmic reticulum (ER) stress and neuron apoptosis. ER stress sensor protein kinase R-like endoplasmic reticulum kinase (PERK) has been reported to induce apoptosis under acute or prolonged ER stress. However, the precise role of PERK in JEV-induced apoptosis and encephalitis remains unknown. Here, we report that JEV infection activates the PERK-ATF4-CHOP apoptosis pathway both in vitro and in vivo. PERK activation also promotes the formation of stress granule, which in turn represses JEV-induced apoptosis. However, PERK inhibitor reduces apoptosis, indicating that JEV-activated PERK predominantly induces apoptosis via the PERK-ATF4-CHOP apoptosis pathway. Among JEV proteins that have been reported to induce ER stress, only JEV NS4B can induce PERK activation. PERK has been reported to form an active molecule by dimerization. The coimmunoprecipitation assay shows that NS4B interacts with PERK. Moreover, glycerol gradient centrifugation shows that NS4B induces PERK dimerization. Both the LIG-FHA and the LIG-WD40 domains within NS4B are required to induce PERK dimerization, suggesting that JEV NS4B pulls two PERK molecules together by simultaneously interacting with them via different motifs. PERK deactivation reduces brain cell damage and encephalitis during JEV infection. Furthermore, expression of JEV NS4B is sufficient to induce encephalitis via PERK in mice, indicating that JEV activates PERK primarily via its NS4B to cause encephalitis. Taken together, our findings provide a novel insight into JEV-caused encephalitis. IMPORTANCE Japanese encephalitis virus (JEV) infection triggers endoplasmic reticulum (ER) stress and neuron apoptosis. ER stress sensor protein kinase R-like endoplasmic reticulum kinase (PERK) has been reported to induce apoptosis under acute or prolonged ER stress. However, whether the PERK pathway of ER stress response plays important roles in JEV-induced apoptosis and encephalitis remains unknown. Here, we found that JEV infection activates ER stress sensor PERK in neuronal cells and mouse brains. PERK activation induces apoptosis via the PERK-ATF4-CHOP apoptosis pathway upon JEV infection. Among the JEV proteins prM, E, NS1, NS2A, NS2B, and NS4B, only NS4B activates PERK. Moreover, activated PERK participates in apoptosis and encephalitis induced by JEV and NS4B. These findings provide a novel therapeutic approach for JEV-caused encephalitis.

The next generation enterprise Xeon server processor maximum configuration supports 18 dual-threaded 64 bit Haswell cores, 45 MB L3 cache, 4 DDR4–2133 MHz memory channels, 40 8 GT/s PCIe lanes, and 40 9.6 GT/s QPI lanes. The processor has 5.56 B transistors on a 31.9 mm $\,\times\,$ 20.8 mm die in Intel's Hi-K metal-gate tri-gate 22 nm CMOS technology with 11 metal layers and achieves up to 33% performance boost. The design supports a wide range of configurations including thermal design power ranging from 55 to 160 W and frequencies ranging from 1.6 to 3.7 GHz. Key architectural innovations include the addition of AVX2 technology, DDR4, and fully integrated voltage regulators (FIVR) that enable per core p-states and uncore frequency scaling.

The transmitter (TX) jitter is critical to the performance of both differential and single-ended signal interfaces. The multi-tone sinusoidal jitter due to the power supply noise accounts for a major portion of the TX jitter. An analytical bit-error-rate method is proposed for accurately evaluating the impact from the multi-tone sinusoidal jitter to the channel performance, which is important for channel design and optimization. The proposed method can accurately capture the channel amplification effect and be seamlessly incorporated into the existing formulation that handles random jitter, deterministic jitter, and duty cycle distortion, etc.

A novel receiver equalization scheme for high-speed links is described in this paper. By per-bit switching the channel-receiver connection, the channel induced inter-symbol interference (ISI) is compensated by receiver (RX) input pole induced ISI. The polarity of the recovered binary bit is adjusted in digital domain to match the transmitted data. An input pole based two-way interleaved switching equalization circuit is proposed and simulated. In comparison with the conventional FIR filter, it improves the output eye width by 63%. This paper provides a new way of converting a low-pass system into a peaking system for link designs, suitable for a broader range of applications.

The next-generation enterprise Xeon server processor maximum configuration supports 18 dual-threaded 64b Haswell cores [1], 45MB L3 cache, 4 DDR4-2133MHz memory channels, 40 8GT/s PCIe lanes, and 60 9.6GT/S QPI lanes. The processor has 5.56B transistors on a 31.9mm×20.8mm die in Intel's high-K metal-gate tri-gate 22nm CMOS technology [2] with 11 metal layers and achieves a 33% performance boost, on average, over previous generations [3]. Two additional metal layers enable area optimization and performance improvement. The design supports a wide range of configurations, including thermal design power ranging from 55 to 165W and frequencies ranging from 1.6 to 3.8GHz. Fig. 4.5.1 shows the processor block diagram of the 18 core die. The floorplan allows for core and cache communication via a ring interconnect, as well as the ability to deliver derivative designs with lower core counts. The 4th column in the 18-core die is removed to implement the 12 core chop, and the 3rd column is removed for an 8 core chop. Key architectural innovations include the addition of AVX2 technology, DDR4, and fully integrated voltage regulators (FIVR) [4] that enable per-core p-states and uncore frequency scaling.

The air is purified under high voltage and high frequency complex electric fields. The results show that the half time T H will drop while the initial concentration N 0 of the aerosol particles reduces indoor, under the joint action of high voltage and high frequency complex electric fields and the filter. The half time T H is reduced when they work together. But there is a obviously delay between the test value and the theoretical value of the half time. The error of experimental results is analyzed. Use exchange efficiency to modify the half time. The error is reduced by more than ten percent by comparison of unmodified model. The modification of the model is reasonable.

A mathematical and physical model of the aerosol coagulation under the joint action of high voltage and high frequency complex electric fields is developed and solution of the half time T H is obtained. At the same time, a set of experimental device is built to verify the theoretical model. The results show that the half time T H will drop while the initial concentration of the aerosol particles reduce in air conditioning room and the air change rate required for concentration halved will reduce with increasing initial concentration. Compared with the theoretical filter model, the half time T H is reduced nearly half when they work together. The time of indoor air purification of air purification of air conditioning is greatly shortened.

We present a current-mode circuit architecture that implements a frequency-shifted version of a model of the mammalian cochlea. Unlike other silicon cochleae that are based on cascades of second order filters, we used a true traveling wave amplifier model as the basis of our circuit architecture. The circuit architecture was accomplished by first transforming a discrete component model into a signal flow graph. Integration terms were then replaced with current-mode integrator circuits. Simulation data of the small-signal gain and phase response, as well as the transient behavior shows that the circuit behaves like a biological cochlea.

A novel differential current-mode integrator (CMI) for voltage-controllable low frequency continuous-time filters is presented. An example fifth-order lowpass filter using the proposed CMI and on-chip capacitors was implemented in an AMI 1.2 /spl mu/m CMOS process, and it achieved -3 dB cutoff frequencies ranging from 160 Hz to 5.6 kHz, by changing a single control voltage.