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SADS-CoV is the documented spillover of a bat coronavirus that causes severe disease in pigs. Pigs are in frequent contact with both humans and other animals and theoretically possess a greater chance, compared to many other species, of promoting cross-species viral transmission.

Swine acute diarrhea syndrome coronavirus (SADS-CoV) is a newly discovered bat-origin coronavirus with fatal pathogenicity for neonatal piglets. There is no vaccine to prevent SADS-CoV infection or clinically approved drugs targeting SADS-CoV. Therefore, unraveling cellular factors that regulate SADS-CoV for cell entry is critical to understanding the viral transmission mechanism and provides a potential therapeutic target for SADS-CoV cure. Here, we showed that Type I interferon (IFN-I) pretreatment potently blocks SADS-CoV entry into cells using lentiviral pseudo-virions as targets whose entry is driven by the SADS-CoV Spike glycoprotein. IFN-I-mediated inhibition of SADS-CoV entry and replication was dramatically impaired in the absence of TET2. These results suggest TET2 is found to serve as a checkpoint of IFN-I-meditated inhibition on the cell entry of SADS-CoV, and our discovery might constitute a novel treatment option to combat against SADS-CoV.

Bats are reservoirs for diverse coronaviruses, including swine acute diarrhea syndrome coronavirus (SADS-CoV). SADS-CoV was first identified in diarrheal piglets in 2017. As a novel alphacoronavirus, SADS-CoV shares ~95% identity with bat alphacoronavirus HKU2. SADS-CoV has been reported to have broad cell tropism and inherent potential to cross host species barriers for dissemination. Thus far, no effective antiviral drugs or vaccines are available to treat infections with SADS-CoV. Therefore, knowledge of the protein-coding gene set and a subcellular localization map of SADS-CoV proteins are fundamental first steps in this endeavor. Here, all SADS-CoV genes were cloned separately into Flag-tagged plasmids, and the subcellular localizations of viral proteins, with the exception of nsp11, were detected using confocal microscopy techniques. As a result, nsp1, nsp3-N, nsp4, nsp5, nsp7, nsp8, nsp9, nsp10, nsp14, and nsp15 were localized in the cytoplasm and nuclear spaces, and these viral proteins may perform specific functions in the nucleus. All structural and accessory proteins were mainly localized in the cytoplasm. NS7a and membrane protein M colocalized with the Golgi compartment, and they may regulate the assembly of SADS-CoV virions. Maturation of SADS-CoV may occur in the late endosomes, during which envelope protein E is involved in the assembly and release of the virus. In summary, the present study demonstrates for the first time the location of all the viral proteins of SADS-CoV. These fundamental studies of SADS-CoV will promote studies of basic virology of SADS-CoV and support preventive strategies for animals with infection of SADS-CoV. IMPORTANCE SADS-CoV is the first documented spillover of a bat coronavirus that causes severe diseases in domestic animals. Our study is an in-depth annotation of the newly discovered swine coronavirus SADS-CoV genome and viral protein expression. Systematic subcellular localization of SADS-CoV proteins can have dramatic significance in revealing viral protein biological functions in the subcellular locations. Furthermore, our study promote understanding the fundamental science behind the novel swine coronavirus to pave the way for treatments and cures.

Mammalian orthoreoviruses (MRVs) infect almost all mammals, and there are some reports on MRVs in China. In this study, a novel strain was identified, which was designated as HLJYC2017. The results of genetic analysis showed that MRV HLJYC2017 is a reassortant strain. According to biological information analysis, different serotypes of MRV contain specific amino acid insertions and deletions in the σ1 protein. Neutralizing antibody epitope analysis revealed partial cross-protection among MRV1, MRV2, and MRV3 isolates from China. L3 gene recombination in MRV was identified for the first time in this study. The results of this study provide valuable information on MRV reassortment and evolution.

Porcine epidemic diarrhea virus (PEDV), a member of the genus Alphacoronavirus, is the predominant cause of severe enteropathogenic diarrhea in swine. A simple, rapid, specific, and sensitive method is critical for monitoring PEDV on pig farms. In this study, a simple and rapid lateral flow immunoassay detection system that integrates europium (Eu) (III) chelate microparticles was developed to identify PEDV in fecal swabs. This newly developed diagnostic sandwich immunoassay utilizes lateral flow test strips (LFTSs). The fluorescence peak heights of the test line (HT) and the control line (HC) were measured using a fluorescence strip reader, and the HT/HC ratio was used for quantitation. The limit of detection of PEDV with this LFTS was ??ten times the median tissue culture infectious dose (TCID50) per mL??. Fecal swab samples were used to determine the cutoff value. Field samples, various PEDV strains and other viruses were used to determine the sensitivity and specificity of the Eu (III) chelate microparticle-based LFTSs, which were 97.8% and 100%, respectively, with a cutoff value of 0.05, as compared with reverse transcription polymerase chain reaction (RT-PCR). In samples from piglets experimentally infected with PEDV, the results were in high agreement with those obtained by RT-PCR. Epidemiological surveillance of PEDV using the LFTSs ??in areas threatened by African swine fever virus?? suggested that the PEDV positive rate on pig farms had significantly decreased, mainly due to the implementation of strict biosecurity measures. The results indicate that the Eu (III) chelate microparticle-based LFTS system is a rapid, sensitive, and reliable method for the identification of PEDV, indicating its suitability for epidemiological surveillance of PEDV infection.

Porcine parvovirus (PPV) NS1, the major nonstructural protein of this virus, plays an important role in PPV replication. We show, for the first time, that NS1 dynamically shuttles between the nucleus and cytoplasm, although its subcellular localization is predominantly nuclear. NS1 contains two nuclear export signals (NESs) at amino acids 283 to 291 (designated NES2) and amino acids 602 to 608 (designated NES1). NES1 and NES2 are both functional and transferable NESs, and their nuclear export activity is blocked by leptomycin B (LMB), suggesting that the export of NS1 from the nucleus is dependent upon the chromosome region maintenance 1 (CRM1) pathway. Deletion and site-directed mutational analyses showed that NS1 contains a bipartite nuclear localization signal (NLS) at amino acids 256 to 274. Coimmunoprecipitation assays showed that NS1 interacts with importins α5 and α7 through its NLS. The overexpression of CRM1 and importins α5 and α7 significantly promoted PPV replication, whereas the inhibition of CRM1- and importin α/β-mediated transport by specific inhibitors (LMB, importazole, and ivermectin) clearly blocked PPV replication. The mutant viruses with deletions of the NESs or NLS motif of NS1 by using reverse genetics could not be rescued, suggesting that the NESs and NLS are essential for PPV replication. Collectively, these findings suggest that NS1 shuttles between the nucleus and cytoplasm, mediated by its functional NESs and NLS, via the CRM1-dependent nuclear export pathway and the importin α/β-mediated nuclear import pathway, and PPV proliferation was inhibited by blocking NS1 nuclear import or export. IMPORTANCE PPV replicates in the nucleus, and the nuclear envelope is a barrier to its entry into and egress from the nucleus. PPV NS1 is a nucleus-targeting protein that is important for viral DNA replication. Because the NS1 molecule is large (>50 kDa), it cannot pass through the nuclear pore complex by diffusion alone and requires specific transport receptors to permit its nucleocytoplasmic shuttling. In this study, the two functional NESs in the NS1 protein were identified, and their dependence on the CRM1 pathway for nuclear export was demonstrated. The nuclear import of NS1 utilizes importins α5 and α7 in the importin α/β nuclear import pathway.

African swine fever virus (ASFV) causes acute, febrile, and highly contagious diseases in swine. Early diagnosis is critically important for African swine fever (ASF) prevention and control in the absence of an effective vaccine. P30 is one of the most immunogenic proteins that are produced during the early stage of an ASFV infection. This makes P30 a good serological target for ASF detection and surveillance. In this study, two P30-reactive monoclonal antibodies (mAbs), 2H2 and 5E8, were generated from mice immunized with recombinant P30 protein (rP30). Epitope mapping was performed with overlapping polypeptides, alanine mutants, and synthetic peptides. The mapping results revealed that 2H2 recognized a region located in the N-terminal, 16-48 aa. In contrast, 5E8 recognized a linear epitope in the C-terminal, 122-128 aa. Further analysis indicated that the epitope recognized by 2H2 was highly conserved in genotypes I and II, while the 5E8 epitope was conserved in most genotypes and the Ser to Pro change at position 128 in genotypes IV, V, and VI did not affect recognition. Overall, the results of this study provide valuable information on the antigenic regions of ASFV P30 and lay the foundation for the serological diagnosis of ASF and vaccine research. KEY POINTS: • Two specific and reactive mAbs were prepared and their epitopes were identified. • 2H2 recognized a novel epitope highly conserved in genotypes I and II. • 5E8 recognized a seven-amino acid linear epitope highly conserved in most genotypes.

African swine fever (ASF) is an acute and highly contagious infectious disease caused by the African swine fever virus (ASFV). Currently, there is no vaccine against ASF worldwide, and no effective treatment measures are available. For this reason, developing a simple, rapid, specific, and sensitive serological detection method for ASFV antibodies is crucial for the prevention and control of ASF. In this study, a 1:1 mixture of gold-labeled p30 and p72 probes was used as the gold-labeled antigen. The p30 and p72 proteins and their monoclonal antibodies were coated on a nitrocellulose membrane (NC) as a test (T) line and control (C) line, respectively. A colloidal-gold dual immunochromatography strip (ICS) for ASFV p30 and p72 protein antibodies was established. The results showed that the colloidal-gold dual ICS could specifically detect ASFV antibodies within 5-10 min. There was no cross-reaction after testing healthy pig serum; porcine reproductive and respiratory syndrome virus (PRRSV), foot-and-mouth disease type A virus (FMDV-A), foot-and-mouth disease type O virus (FMDV-O), porcine circovirus type 2 (PCV-2), and classical swine fever virus (CSFV) positive sera. A positive result was obtained only for the positive control P1. The sensitivity of the test strips was 1:256, which was equivalent to that of commercially ELISA kits. Their coincidence rate with the two commercial ASFV ELISA antibodies detection kits was higher than 98%. The test strips were stably stored at 18-25 °C and 4 °C for 4 and 6 months, respectively. The colloidal-gold dual ICS prepared in this study had high sensitivity and specificity and were characterized by rapid detection, simple operation, and easy interpretation of results. Therefore, they are of great significance to diagnose, prevent, and control African swine fever. KEY POINTS: • We establish an antibody detection that is quick and can monitor an ASF infection. • We observe changes in two protein antibodies to dynamically monitor ASF infection. • We use diversified detection on a single test strip to detect both antibodies.

In this study, the pathogenicity of porcine deltacoronavirus (PDCoV) strain NH (passage 10, P10) was evaluated. We found that PDCoV strain NH is enteropathogenic in 5‐day‐old pigs. Pathogenicity experiments provided a challenge model for studying the protection efficiency of passive immunity. In order to investigate the protective efficacy of passive immunity in newborn piglets, pregnant sows were vaccinated with either a PDCoV‐inactivated vaccine at the Houhai acupoint (n = 5) or DMEM as a negative control (n = 2) using a prime/boost strategy 20 and 40 days before delivery. PDCoV spike (S)‐specific IgG and neutralizing antibody (NA) responses were detected in immunized sows and piglets born to immunized sows. PDCoV spike (S)‐specific sIgA was also detected in the colostrum and milk of immunized sows. Five days post‐farrowing, piglets were orally challenged with PDCoV strain NH (105 TCID50/piglet). Severe diarrhoea, high levels of viral RNA copies and substantial intestinal villus atrophy were detected in piglets born to unimmunized sows. Only 4 of 31 piglets (12.9%) born to immunized sows in the challenge group displayed mild to moderate diarrhoea, lower viral RNA copies and minor intestinal villi damage compared to piglets born to unimmunized sows post‐challenge. Mock piglets exhibited no typical clinical symptoms. The challenge experiment results indicated that the inactivated PDCoV vaccine exhibited 87.1% protective efficacy in the piglets. These findings suggest that the inactivated PDCoV vaccine has the potential to be an effective vaccine, providing protection against virulent PDCoV.

This study is concerned with the nonlinear frequency response characteristics of a spur gear pair system, in which the modeling of time varying mesh stiffness (TVMS) and static transmission error (STE) is stressed. Firstly, a complete modeling procedure is constructed by adopting existing models of TVMS, STE and gear pair, so that the basic gear features and design parameters are contained in the overall gear model. On this basis, a 1 degree-of-freedom (DOF) spur gear pair model is established including the TVMS, STE and nonlinear backlash. Then, to show the validity and reliability, theoretical solutions of the dynamic model are verified by the published numerical results and experimental data. Besides, the stability of the gear system is investigated analytically to obtain the boundaries that separate stable and unstable regions. Finally, parametric studies are conducted to reveal the effects of several key parameters, such as the contact ratio, spacing error, transmitted load and damping ratio. The results show that the modeling of TVMS and STE should be considered and emphasized to obtain precise predictions of system responses and to reveal in depth properties of gear dynamics. Furthermore, the parametric studies and stability analysis offer useful suggestions for researchers and engineers to achieve desirable design and control of dynamic behaviors of gear system.

Porcine deltacoronavirus (PDCoV) is a pathogen belonging to the genus Deltacoronavirus that in 2014 caused outbreaks of piglet diarrhea in the United States. To identify suitable therapeutic targets, a more comprehensive understanding of the viral entry pathway is required, particularly of the role of proteases. Here, we identified the proteases that activate the viral spike (S) glycoprotein to initiate cell entry and also pinpointed the host-cellular pathways that PDCoV uses for entry. Our results revealed that cathepsin L (CTSL) and cathepsin B (CTSB) in lysosomes and extracellular trypsin in cell cultures independently activate the S protein for membrane fusion. Pretreating the cells with the lysosomal acidification inhibitor bafilomycin-A1 (Baf-A1) completely inhibited PDCoV entry, and siRNA-mediated ablation of CTSL or CTSB expression significantly reduced viral infection, indicating that PDCoV uses an endosomal pathway for entry. Of note, trypsin treatment of cell cultures also activated PDCoV entry, even when the endosomal pathway was inhibited. This observation indicated that trypsin-induced S protein cleavage and activation in cell cultures enables viral entry directly from the cell surface. Our results provide critical insights into the PDCoV infection mechanism, uncovering two distinct viral entry pathways: one through cathepsin L and cathepsin B in the endosome and another via a protease at the cell surface. Because PDCoV infection sites represent a proteases-rich environment, these findings suggest that endosome inhibitor treatment alone is insufficient to block PDCoV entry into intestinal epithelial cells in vivo. Therefore, approaches that inhibit viral entry from the cell membrane should also be considered.

Highlights • p53 exhibits clear antiviral role in PEDV infection. • Enhanced PEDV replication in p53-knockout cells is related to attenuated IFN pathway. • Enhance p53 expression provides a new strategy to control PEDV infections., p53 is a tumor suppressor gene that can be activated in many contexts, such as DNA damage or stressful conditions. p53 has also been shown to be important for responses to certain viral infections. Porcine epidemic diarrhea virus (PEDV) is a major enteric pathogen of the coronavirus family that causes extensive mortality among piglets. The involvement of p53 during PEDV infection has not previously been investigated. In this study, we detected p53 upregulation in response to PEDV infection. Treatment with a p53 specific activator or p53 overexpression markedly decreased viral replication, and we showed that there was more viral progeny produced in p53 knock-out cells than in p53 wild-type cells. Finally, we demonstrated that inhibition of viral infection by p53 was mediated via p53-dependent IFN signaling, leading to IFN-stimulated response element (ISRE) activation, as well as the upregulation of IFN-stimulated genes (ISGs) and IFN-β released from infected cells. These findings demonstrate that p53 suppresses PEDV infection, offering a novel therapeutic strategy for combatting this deadly disease in piglets.

Emerging evidence has indicated that microRNAs (miRNAs) play an important role in cervical cancer (CC). However, the role of miRNA (miR)‐665 in cervical cancer remains unclear. The aim of the present study was to investigate the potential functions of miR‐665 in CC and to identify the underlying mechanisms of action. Herein, we show that miR‐665 was downregulated in CC tissues and cell lines, which is negatively correlated with tumor size, distant metastasis, advanced TNM stage and poor prognosis. Functionally, miR‐665 inhibited cell proliferation, migration and invasion and resistance of cisplatin for CC cells, as well as tumor growth. We validated that transforming growth factor beta receptor 1 (TGFBR1) was a direct target of miR‐665 and mediated the ERK/SMAD pathway. In addition, we identified miR‐665 as the competing endogenous RNA for long noncoding (lnc)‐DANCR. These observations suggested that lnc‐DANCR‐mediated miR‐665 downregulation regulates the malignant phenotype of CC cells by targeting TGFBR1 through the ERK/SMAD pathway, which may present a pathway for novel therapeutic stratagems for CC therapy.

Transmissible gastroenteritis (TGE), caused by transmissible gastroenteritis virus (TGEV), is a highly infectious disease in pigs. Vaccination is an effective approach to prevent TGEV infection. Here, we evaluated the potential of TGEV S1 as a DNA vaccine and porcine interleukin (pIL)-12 as an adjuvant in a mouse model. A DNA vaccine was constructed with the TGEV S1 gene to induce immune response in an experimental mouse model; pIL-12 was chosen as the immunological adjuvant within this DNA vaccine. The pVAX1-(TGEV-S1) and pVAX1-(pIL-12) vectors were transfected into BHK-21 cells and expressed in vitro. Experimental mice were separately immunized with each of the recombinant plasmids and controls through the intramuscular route. The lymphocytes isolated from the blood and spleen were analyzed for proliferation, cytotoxic activities, and populations of CD4+ and CD8+ cells. The titers of TGEV S1 in an enzyme-linked immunosorbent assay (ELISA) and TGEV neutralizing antibodies and the concentrations of interferon (IFN)-γ and IL-4 were also analyzed in the serum. The plasmids pVAX1-(TGEV-S1) and pVAX1-(pIL-12) could be expressed in BHK-21 cells, and the combination of pVAX1-(TGEV-S1) and pVAX1-(pIL-12) could induce a significant increase in all markers. pIL-12 could act as an immunological adjuvant in the DNA vaccine for TGEV-S1. Furthermore, the DNA vaccine prepared using TGEV-S1 and porcine IL-12 could induce excellent humoral and cellular immune responses.

African swine fever (ASF) is one of the most severe infectious diseases of pigs. In this study, a LAMP assay coupled with the CRISPR Cas12a system was established in one tube for the detection of the ASFV p72 gene. The single-strand DNA-fluorophore-quencher (ssDNA-FQ) reporters and CRISPR-derived RNA (crRNAs) were screened and selected for the CRISPR detection system. In combination with LAMP amplification assay, the detection limit for the LAMP-CRISPR assay can reach 7 copies/μl of p72 gene per reaction. Furthermore, this method displays no cross-reactivity with other porcine DNA or RNA viruses. The performance of the LAMP-CRISPR assay was compared with real-time qPCR tests for clinical samples, a good consistency between the LAMP-CRISPR assay and real-time qPCR was observed. In the current study, a LAMP coupled with the CRISPR detection method was developed. The method shed a light on the convenient, portable, low cost, highly sensitive and specific detection of ASFV, demonstrating a great application potential for monitoring on-site ASFV in the field.

Porcine epidemic diarrhea virus (PEDV) has been prevalent for many years. The viral spike (S) protein is the major target of neutralizing antibodies. However, there is little understanding of the locations of the neutralizing antibody epitopes in the spike structure. Here, we used a polyclonal antibody (pAb) against PEDV and a neutralizing monoclonal antibody (mAb) to isolate escape mutants of PEDV strain LNCT2. Finally, we isolated an escape mutant strain of PEDV, mutant-1B9, but still neutralized by the pAb. Analysis showed two regions deleted in the S protein which allowed mutant-1B9 to escape neutralization by mAb 1B9. These results suggest the deleted amino acids participate in the formation of conformational epitope and provides valuable information for mapping conformational epitopes. Importantly, no PEDV escape mutants were generated by treatment with pAbs, which suggests the potential utility of pAbs or combination therapies based on several mAbs in controlling PEDV infections.

Highlights • A rapid immunochromatographic strip test for the detection of porcine epidemic diarrhea virus specific SIgA in colostrum was established. • The rapid immunochromatographic strip test is sensitive as compared with ELISA. • The rapid immunochromatographic strip test can be used to epidemiological surveillance as well as vaccine immunity assessment., Porcine epidemic diarrhea virus (PEDV) causes very high mortality in newborn piglets. The mucosal immune system in the gut must eliminate potential pathogens while maintaining a mutually beneficial relationship with the commensal microbiota. Antibodies derived from the secretory immunoglobulin A (SIgA) class, act as the first line of antigen-specific immunity in the gut by recognizing both pathogens and commensals. Therefore, the measurement of SIgA levels is an important index in evaluating PEDV infections and immune status. A simple and rapid method for the detection of PEDV-specific SIgA using an immunochromatographic test strip has been developed; incorporating a colloidal gold-labeled anti-SIgA secretory component (SC) mAb probe for the detection of anti-PEDV-specific SIgA in swine. On the strip, a gold-labeled anti-SIgA SC mAb was applied to a conjugate pad; purified PEDV particles and goat anti-mouse antibodies were blotted onto a nitrocellulose membrane to form the test and control lines, respectively. Results showed that the immunochromatographic test strip had high sensitivity and specificity. When compared with enzyme-linked immunosorbent assay, kappa value suggesting that the strip could be used to detect PEDV specific SIgA in colostrum samples. Furthermore, the strip assay is rapid and easy to perform with no requirement for professional-level skills or equipment. We found that the immunochromatographic test strip was a rapid, sensitive, and reliable method for the identification of PEDV specific SIgA, indicating its suitability for epidemiological surveillance as well as vaccine immunity when studying PEDV.

Background Salmonella Enteritidis (SE) is one of the major foodborne zoonotic pathogens of worldwide importance which can induce activation of NLRC4 and NLRP3 inflammasomes during infection. Given that the inflammasomes play an essential role in resisting bacterial infection, Salmonella has evolved various strategies to regulate activation of the inflammasome, most of which largely remain unclear. Results A transposon mutant library in SE strain C50336 was screened for the identification of the potential factors that regulate inflammasome activation. We found that T3SS-associated genes invC, prgH, and spaN were required for inflammasome activation in vitro. Interestingly, C50336 strains with deletion or overexpression of Dam were both defective in activation of caspase-1, secretion of IL-1β and phosphorylation of c-Jun N-terminal kinase (Jnk). Transcriptome sequencing (RNA-seq) results showed that most of the differentially expressed genes and enriched KEGG pathways between the C50336-VS-C50336Δdam and C50336-VS-C50336::dam groups overlapped, which includes multiple signaling pathways related to the inflammasome. C50336Δdam and C50336::dam were both found to be defective in suppressing the expression of several anti-inflammasome factors. Moreover, overexpression of Dam in macrophages by lentiviral infection could specifically enhance the activation of NLRP3 inflammasome independently via promoting the Jnk pathway. Conclusions These data indicated that Dam was essential for modulating inflammasome activation during SE infection, there were complex and dynamic interplays between Dam and the inflammasome under different conditions. New insights were provided about the battle between SE and host innate immunological mechanisms.

Additional file 1: Figure S1. Growth curves of dam, invC, hilD, prgH, and spaN gene deletion mutants, complementation, and overexpression strains. Figure S2. Two rounds of screening to identify the genes involved in regulating inflammasome activation in vitro (original images of immunoblotting). Figure S3. Deletion mutants of dam, invC, prgH, and spaN failed to induce inflammasome activation (original images of immunoblotting). Figure S4. Deletion of prgH did not influence the synthesis of inflammasome components (original images of immunoblotting). Figure S5. Overexpression of Dam inhibited inflammasome activation (original images of immunoblotting). Figure S6. The ability of the dam complementation strain and overexpression strain cultured without IPTG to activate the inflammasome was improved (original images of immunoblotting). Figure S7. The deletion of Dam blocked the Jnk pathway in infected J774A.1 cells (original images of immunoblotting). Figure S8. Dam independently promoted NLRP3 inflammasome activation (original images of immunoblotting).

This paper investigates a combined cooling and power system driven by geothermal energy for ice-making and hydrogen production. The proposed system combines geothermal flash cycle, Kalina cycle, ammonia-water absorption refrigeration cycle and electrolyser. The geothermal energy can be efficiently converted to storable hydrogen and ice. Based on mathematical model, some key parameters are analyzed to figure out their effect on the exergetic performance. An exergy destruction analysis for all components has been performed to find out the distribution of exergy inefficiency. The system exergetic efficiency is optimized by Jaya algorithm and Genetic algorithm and the optimization results are compared. According to the parametric analysis, the exergy efficiency decreases as the back pressure of steam turbine and the back pressure of ammonia-water turbine increase. The exergy efficiency could increase first and then decline, as flash pressure, ammonia-water turbine inlet pressure and ammonia mass fraction of basic solution increase. The optimization results show that the exergy efficiency reaches 23.59%, 25.06% and 26.25% when the geothermal water temperature is 150 °C, 160 °C and 170 °C. Jaya algorithm has highly precise optimization results.

Combined cooling and power system has gained extensive attention from government and publics throughout the world due to fuel saving, high energy utilization efficiency and different energy forms output. In this paper, a novel combined cooling and power system comprising a supercritical CO2 (sCO2) power cycle and a vapor absorption refrigeration cycle with lithium bromide as the working fluid is proposed. A comparative study is conducted between this system and the combined sCO2/ammonia-water system to show its advantages and potential on the basis of the self-built thermodynamic simulation platform. The influence of different variables including turbine inlet temperature, pressure ratio in sCO2 cycle and evaporating temperature on the system performance is analyzed. Single-objective optimization relying on the genetic algorithm and multi-objective optimization based on the NSGA-II method are used to further investigate and compare the performance of above two cycles. Optimization results reveal that compared with the combined sCO2/ammonia-water system, the proposed sCO2/LiBr-H2O system could gain improvement on CORP by 0.3112 at the expensive of COPP drop by 0.0004 excepting the advantage of extreme low pump outlet pressure in bottoming cycle. Besides, sCO2/LiBr-H2O system is relatively easier to reach the balance between power and cooling.

In this paper, two configurations of Kalina-Flash cycles (KFC) are proposed to recover low-grade heat source. The thermodynamic and economic models of Kalina-Flash cycles are established. A numerical simulation is conducted, and a parametric analysis is performed to examine the effect of five key parameters, including separator temperature, separator pressure, ammonia mass fraction of ammonia-water basic solution, flash pressure and pinch-point temperature difference, on the thermodynamic and economic performances of Kalina-Flash cycles. Furthermore, a single-objective optimization and a multi-objective optimization are carried out by genetic algorithm and Non-dominated sorting genetic algorithm-II to obtain the optimum thermodynamic and economic performances. The single-objective optimization results show that the Kalina-Flash cycles can achieve higher exergy efficiency and lower specific investment cost than Kalina cycle does. The multi-objective optimization results of Kalina-Flash cycles present the Pareto frontier solutions, which is a series of optimum solutions for exergy efficiency and total capital investment. The Pareto frontier solutions indicate that Kalina-Flash cycles are superior to Kalina cycle in the aspect of thermodynamic and economic performances.

// Yu Mao 1 , Lixin Dong 1 , Jia Liu 2 , Liang Li 3 , Le Wang 4 , Yan Zhou 5 , Yanqiu Zhang 1 , Sen Yang 1 , Liyan Cao 1 , Chao Wang 6 and Zhanzhao Fu 1 1 Department of Oncology, The First Hospital of Qinhuangdao, Qinhuangdao, Hebei, China 2 Institute of Basic Medical Sciences, Qilu Hospital, Shandong University, Jinan, China 3 Department of Ultrasound, Beijing Anzhen Hospital, Capital Medical University, Beijing, China 4 Department of Neurosurgery, Tianjin Medical University General Hospital, Tianjin Neurological Institute and Laboratory of Neuro-Oncology, Tianjin, China 5 Department of Oncology Radiation, Tianjin Medical University General Hospital, Tianjin, China 6 Department of Thoracic Surgery, The First Hospital of Qinhuangdao, Qinhuangdao, China Correspondence to: Zhanzhao Fu, email: doctors12email@163.com Keywords: ESCC; progression; long non-coding RNA; CCAT1 Received: February 27, 2017 Accepted: August 23, 2017 Published: January 02, 2018 ABSTRACT Dysregulation of long non-coding RNA (lncRNAs) plays vital roles in tumorigenesis and cancer progression. Previous studies have identified the role of the lncRNA CCAT1 as an oncogene in several cancer types, and ectopic expression of CCAT1 predicts a poor prognosis. This study sought to determine the underlying mechanism for this observation in esophageal squamous cell carcinoma (ESCC). We found that CCAT1 was significantly upregulated in human ESCC tumor tissues and cell lines. LncRNA CCAT1 overexpression enhanced cell proliferation, migration, and invasion in vitro and in vivo . Our bioinformatics analysis and RNA immunoprecipitation assays combined with dual-luciferase assays revealed that CCAT1 functions as a microRNA (miRNA) sponge for miR-543. Increased CCAT1 antagonized the functions of miRNA-543 and led to de-repression of its downstream target, KRAS, which is a core oncogene that facilitates ESCC progression. Our findings suggest that CCAT1 increases KRAS expression by sponging miR-543 and thus promotes ESCC progression. This study sheds light on the potential role of lncRNAs as a novel prognostic biomarker and provides a new therapeutic target for ESCC.

Porcine epidemic diarrhea virus (PEDV) has two genotypes, G1 and G2. To research the immunogenicity differences of PEDV G1 and G2 genotype strains and obtain a neutralizing monoclonal antibody (mAb), we inoculated specific-pathogen-free BALB/c mice with a newly emerged strain, PEDV-LNCT2. After immunizations, cells from the spleen of the mice were fused with SP2/0 myeloma cells. Following culturing and subcloning, a strain, 1B9, secreting neutralizing antibody, was obtained. The 1B9 mAb neutralized new variant genotype 2 PEDV strains (LNCT2, LNSY, and Hjms), but it did not neutralize a genotype 1 PEDV strain (CV777), in vitro. Results showed that the epitope recognized by the 1B9 mAb lies in the spike protein, and that it is a conformational epitope. These findings confirm that allelic differences in the PEDV S gene between the G1 and G2 genotype strains led to changes in the S protein and, thus, differences in its immunogenicity., Highlights • The mAb of 1B9 could neutralize PEDV new variant strains from genotype 2. • The mAb of 1B9 could not neutralize PEDV strain from genotype 1. • The antiviral strategy of mAb 1B9 work by combination with the S protein of PEDV. • The epitope recognized by mAb 1B9 is a conformational epitope.

This paper investigates a Kalina-based combined cooling and power (CCP) cycle driven by low-grade heat source. The proposed cycle consists of a Kalina cycle and an absorption refrigeration cycle. By establishing the mathematical model, numerical simulation is conducted and parametric analysis is performed to examine the effects of five key parameters on the thermodynamic performances of Kalina-based CCP cycle. A performance optimization is conducted by genetic algorithm to obtain the optimum exergy efficiency. According to parametric analysis, an optimum expander inlet pressure can be achieved; exergy efficiency increases with expander inlet pressure and concentration of ammonia-water basic solution, but exergy efficiency decreases when terminal temperature difference of high-temperature recuperator and low-temperature recuperator increases. Refrigeration exergy increases with expander inlet pressure and decreases as expander inlet temperature and concentration of ammonia-water basic solution rise. However, the refrigeration exergy keeps constant as the terminal temperature difference of high-temperature recuperator and low-temperature recuperator vary. Furthermore, the optimized Kalina-based CCP cycle is compared with a separate generation system which is also optimized. The optimization results show that the exergy efficiency and net power output of Kalina-based CCP are higher than those of separate generation system.

Background In cancer progression, hypoxia, or low oxygen tension, is a major regulator of tumor aggressiveness and metastasis. However, how cancer cells adapt to the hypoxia and communicate with other mesenchymal cells in microenvironment during tumor development remains to be elucidated. Here, we investigated the involvement of exosomes in modulating angiogenesis and enhancing metastasis in esophageal squamous cell carcinoma (ESCC). Methods Differential centrifugation, transmission electron microscopy and nanoparticle tracking analysis were used to isolate and characterize exosomes. Colony formation and transwell assay were performed to assess the proliferation, migration and invasion of human umbilical vein endothelial cells (HUVECs). The tube formation assay and matrigel plug assay were used to evaluate the vascular formation ability of HUVECs in vitro and in vivo respectively. An in vivo nude mice model was established to detect the regulatory role of exosomes in ESCC progression. Microarray analysis was performed to analyze the transcriptome profiles in HUVECs. Results Exosomes derived from ESCC cells cultured under hypoxia played a better role in promoting proliferation, migration, invasion and tube formation of HUVECs in vitro and in vivo than exosomes from ESCC cells cultured under normoxia. Moreover, hypoxic exosomes significantly enhanced the tumor growth and lung metastasis compared with normoxic exosomes in nude mice models. Interestingly, endothelial cells were programmed by hypoxic and normoxic exosomes from ESCC cells which altered the transcriptome profile of HUVECs. Conclusions Taken together, our data identified an angiogenic role of exosomes from ESCC cells which shed light on the further application of exosomes as valuable therapeutic target for ESCC. Electronic supplementary material The online version of this article (10.1186/s13046-019-1384-8) contains supplementary material, which is available to authorized users.

Silicon nitride (Si3N4) based ceramic tools exhibit good machinability in cutting materials such as gray cast iron, ductile iron, malleable cast iron, and superalloys due to excellent high-temperature mechanical properties. In this paper, high-performance Si3N4-based ceramic tools containing tungsten carbide (WC) and cobalt (Co) were studied. Effects of the WC content and Co content on mechanical properties and a microstructure of Si3N4-based ceramic materials were analyzed. Results showed that Si3N4-based ceramic material containing 10 wt % WC and 1 wt % Co had the best comprehensive mechanical properties at a sintering temperature of 1650 &deg, C and holding time of 6 min, achieving Vickers hardness, fracture toughness, and room temperature bending strength of 16.96 GPa, 7.26 MPa&middot, m1/2, and 1132 MPa, respectively. The microstructure of Si3N4-based ceramic tool material is uniform without obvious abnormal growth. The Si3N4-based ceramic tool was mainly composed of &alpha, Si3N4, &beta, Si3N4, and WC phases.

The geothermal energy is a renewable energy resource, which is viewed as a promising alternative to fossil energy. Powered by geothermal energy, the combined cooling heating and power (CCHP) system can potentially become an option for efficient energy supply. However, the operation of the CCHP system is subject to energy demand and temperature degradation of geothermal water. To capture the dynamic characteristics and off-design performance of CCHP system under different working conditions, the dynamic mathematical models of a CCHP system is established and a control strategy is proposed. On this basis, the effect of heating/cooling load on the dynamic behavior of the CCHP system is analyzed and the effect of temperature degradation of geothermal water on the off-design performance is investigated. The results indicate that the lower heating/cooling load leads to greater overshoot and longer settling time in the dynamic process. The settling time of Cooling-Power mode is much longer than that of Heating-Power mode. As the temperature of geothermal water decreases from 120 °C to 108 °C, the heating capacity of the CCHP system decreases by 28.87% and the cooling capacity decreases by 14.72%.In addition, the operation simulation shows that the CCHP system can precisely track hourly heating and cooling load of the student dorm building.

A CCP (combined cooling and power) system, which integrated a flash-binary power generation system with a bottom combined cooling and power subsystem operating through the combination of an organic Rankine cycle and an ejector refrigeration cycle, was developed to utilize geothermal energy. Thermodynamic and exergoeconomic analyses were performed on the system. A performance indicator, namely the average levelized costs per unit of exergy products for the overall system, was developed to assess the exergoeconomic performance of the system. The effects of four key parameters including flash pressure, pinch point temperature difference in the vapor generator, inlet pressure and back pressure of the ORC turbine on the system performance were evaluated through a parametric analysis. Two single-objective optimizations were conducted to reach the maximum exergy efficiency and the minimum average levelized costs per unit of exergy products for the overall system, respectively. The optimization results implied that the most exergoeconomically effective system couldn't obtain the best system thermodynamic performance and vice versa. An exergy analysis based on the thermodynamic optimization result revealed that the biggest exergy destruction occurred in the vapor generator and the next two largest exergy destruction were respectively caused by the steam turbine and the flashing device.

Nuclear energy is a kind of stable, controllable and cleaner energy without massive discharge of pollutant. A comprehensive investigation on the design and off-design performance of supercritical carbon dioxide power system is conducted for the small-scale lead-cooled fast reactor in this paper. A suitable design operating condition is determined based on the system thermodynamic model and exergoeconomic model in the design stage. The off-design condition models of turbine, compressor and heat exchangers are established. Five kinds of off-design control strategies and their relationship with cleaner production and sustainable development are studied under different grid loads conditions. Results show that the system thermal efficiency can reach upto 32.18% with the optimal total product unit cost of 21.33$⋅GJ−1 in the design stage. A designed centrifugal compressor based on the demonstrated Two-zone model displays good aerodynamic performance and a wide off-design operating range. The off-design performance analysis exhibits that all control strategies can complete the adjustment of power output over a range of 10%–100%. Inventory control is the best control strategy. Cleaner production coefficient decreases with the grid load for all control strategies, and this research can provide references for cleaner production and promote the sustainable development of society effectively.

This paper investigates a combined cooling and power (CCP) system driven by a low-grade heat source. This system is a combination of the Kalina cycle and an ammonia-water absorption refrige...

To construct the expression vector of apolipoprotein B mRNA editing enzyme catalytic subunit 3A( APOBEC3A),express APOBEC3 A in eukaryotic cells and identify its cytosine deaminase activity.The APOBEC3 A gene was obtained by PCR and inserted into the eukaryotic expression vector pc DNA3. 0( +). The recombinant vector pc DNA3. 0-APOBEC3 A was then transfected into HEK293 T and Hep G2 cells after confirmed by DNA sequencing. The recombinant protein was purified by Ni-NTA His Bind affinity column. Western blot analysis was used to detect the expression of APOBEC3 A protein. The localization of APOBEC3 A protein in HEK293 T and Hep G2 cel s was identified by immunofluorescence cytochemistry. The deaminase activity of APOBEC3 A protein was characterized by fluorescence polarization.DNA sequencing confirmed that APOBEC3 A gene( 600 bp) was inserted into pc DNA3. 0-APOBEC3 A,which was expressed in HEK293 T and Hep G2 cells successfully. APOBEC3 A protein was mainly expressed in cytoplasm of HEK293 T cells and cytoplasm and nuclei of Hep G2 cells. APOBEC3 A protein showed cytosine deaminase activity on the TTCA sequence in single-stranded DNA.The study constructed successfully APOBEC3 A eukaryotic expression vector,identified the differential expression of APOBEC3 A protein in HEK293 T and Hep G2 cells,and confirmed that the APOBEC3 A protein had cytosine deaminase activity.

Aim We investigated whether plasma levels of lysophosphatidic acid (LPA) could serve as a diagnostic indicator for assessing disease progression in ovarian cancer (OC) patients. Material and Methods In this study, we enrolled 98 patients with OC, 70 patients with benign ovarian tumors and 75 healthy controls. Plasma levels of LPA and cancer antigen 125 (CA-125) were measured in all study subjects. The diagnostic values of LPA and CA-125 plasma levels were evaluated and an updated meta-analysis was performed to examine the association between LPA plasma levels and OC progression. Statistical analyses were performed with spss 18.0 and R 3.1.0 software. Results In our case–control study, OC patients showed significantly higher plasma LPA levels compared to patients with benign tumors and healthy controls (all P

The biomass fuel is a renewable energy resource, which is viewed as a promising alternative to fossil energy. This paper investigates a biomass-fired Kalina cycle with a regenerative heater which is generally utilized to heat the feedwater and to increase the efficiency in coal-fired steam power plant. The mathematical model of the biomass-fired Kalina cycle with a regenerative heater is established to conduct numerical simulation. A parametric analysis is conducted to examine the effects of some key thermodynamic parameters on the system performance. Furthermore, a parametric optimization is carried out by genetic algorithm to obtain the optimum performance of system. The results demonstrate that there exists an optimum extraction pressure and its corresponding maximum fraction of flow extracted from turbine to maximize the net power output and system efficiency. In addition, a higher turbine inlet pressure or turbine inlet temperature leads to higher net power output and system efficiency. And net power output and system efficiency increases as separator temperature rises. The optimization result of the biomass-fired Kalina cycle with/without regenerative heater indicates the system is more efficient when regenerative heater is added.

Porcine stool-associated RNA virus 1 (Posavirus 1) is a novel member of picornaviruses and first identified from fecal samples of 30-day-old pigs with diarrhea in USA in 2011. To evaluate the existence of Posavirus 1 in swine herds, 118 clinical samples from diarrheal pigs and 31 fecal swabs from healthy pigs were collected and detected by reverse transcription-polymerase chain reaction (RT-PCR) using Posavirus 1-specific primers. Only five fecal samples from diarrheal pigs on two swine farms were positive for Posavirus 1. The complete genome sequences [excluding poly (A) tail] of two representative isolates SDQD-25 and HBTS-11 are determined and consist of 9840 and 9819 nucleotides in length, and encode one putative polyprotein of 3070 and 2952 amino acids, respectively. They share 90.3% homology with each other and 81.3-95.4% homologies with American Posavirus 1 isolates or strains at the nucleotide sequence level. The phylogenetic analysis based on the entire genomes of reference picornavirus strains or isolates showed SDQD-25, HBTS-11 cluster together with American Posavirus 1 isolates or strains, yet are clearly distant from the other picornaviruses. The complete genome sequences of Chinese Posavirus 1 isolates will enrich the information of Posavirus 1 sequence database and further expedite posavirus research on the genetic diversity, epidemiology, and evolution in China.