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Porcine reproductive and respiratory syndrome (PRRS) is a highly contagious and virulent infectious disease caused by the porcine reproductive and respiratory syndrome virus (PRRSV), which has substantial economic losses in the pig industry worldwide, and PRRSV attenuated vaccines and inactivated vaccines do have limitations in immune protection. The discovery of new antiviral targets has become a new research field. The proteomic studies have shown that the PRRSV NSP2 protein interacts with tripartite motif protein 4 (TRIM4), but it was still unknown whether TRIM4 regulates PRRSV infections. In this study, the TRIM4 gene from Marc-145 cells was cloned, and it was proved that TRIM4 overexpression inhibits PRRSV replication, whereas TRIM4 small-interfering-RNA knockdown resulted in increased virus titers. Mechanism investigation indicated that TRIM4 inhibits PRRSV replication through ubiquitination and degradation of the NSP2 protein. Protease inhibitor MG132 (carbobenzoxy-Leu-Leu-leucinal) attenuated the TRIM4-driven degradation of NSP2. Taken together, TRIM4 impairs PRRSV proliferation via ubiquitination and degradation of NSP2., (© 2022. The Author(s).)

Background: This study examined the role of anxiety and coronavirus disease 2019 (COVID-19) burnout in the relationship between coronavirus stress and overeating among Chinese college students during the COVID-19 pandemic., Methods: Chinese college students (N = 2926; M age  = 19.90, SD = 1.47, range = 18-25 years old; 54.34% female) completed self-reported online questionnaires regarding coronavirus stress, anxiety, COVID-19 burnout, and overeating., Results: Anxiety showed partially indirect effect on the association between coronavirus stress and overeating. COVID-19 burnout exacerbated the indirect pathway between coronavirus stress and overeating via anxiety., Discussion and Conclusion: This is the first study, to our knowledge, that examines the underlying mechanisms of the coronavirus stress and overeating behavior association among Chinese college students. The results support several existing theories on stress and problematic eating behaviors and provide practical implications for prevention and intervention programs of overeating during the COVID-19 pandemic., (© 2022. The Author(s).)

Background: This study examined the mediating effect of sense of control and the moderating effect of coronavirus stress on the relationship between life history strategy and overeating among Chinese college students during the COVID-19 period., Methods: 3310 Chinese students (M age  = 19.74, SD = 1.50; 47% males) completed self-reported questionnaires regarding life history strategy, sense of control, overeating, and coronavirus stress. The data were analyzed using Pearson's r correlations and moderated mediation analysis., Results: The results revealed that control sense mediated the link between life history strategy and college students' overeating. College students' coronavirus stress moderated the associations between life history strategy and college students' sense of control and between control sense and overeating. The association between life history strategy and sense of control was stronger for those with lower coronavirus stress, and the association between sense of control and overeating was stronger for those with lower coronavirus stress., Conclusions: This study identified that the critical factors were associated with overeating. On the one hand, the research deepens the application and interpretation of life history theory in the field of eating; on the other hand, it provides evidence for the prevention of overeating, and provides theoretical basis for psychological assistance among Chinese college students., (© 2021. The Author(s).)

Classical swine fever virus (CSFV) is a member of the genus Pestivirus, which causes serious economic losses. The re-emergence of the disease in Japan in 2018 has increased awareness of CSFV. In this study, Balb/c mice were immunized with plant-derived E2 protein, and four monoclonal antibodies (mAbs) 4B11, 7B3, 11A5 and 6F3 were generated. Two of these mAbs, 4B11 and 7B3, effectively blocked CSFV infection of PK-15 cells. Both mAbs recognized a novel linear epitope, 256 CLIGNTTVKVHASDER 271 . The neutralizing ability of anti-CSFV serum decreased 63%, when pre-incubated with the linear peptide at 200 μg/mL. Structural analysis showed that this linear epitope is present at the border of Domain C and Domain D on the surface of the E2 protein. Alignment of amino acid sequences showed that the epitope was conserved in different subgroups of CSFV but not in other members of the Pestivirus genus. Consistently with the analysis above, this epitope distinguished antibodies against CSFV from those against bovine viral diarrhea virus (BVDV). Our study provides an ideal candidate peptide for new vaccine design and differential diagnosis of CSFV. These findings will contribute to the control and eradication of classical swine fever., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Message framing plays an important role in advertising strategies and has been studied from various perspectives in different behavioral researches. In this study Event Rated Potentials technique helped to examine the neural mechanism of message framing effect on self-conscious emotions of pride and guilt regarding consumer purchase intention in the context of green marketing. Behavioral results showed that participants ranked higher on positive framing compared to negative framing. ERP results declared that N1 component was elicited by positive framed message with emotion of pride and guilt, reflecting use of attentional resources to acquire potential benefits at first stage of processing emotional information. At the second stage P2 was higher for negative framing containing pride and guilt slogan, showing more attention towards processing emotional information about potential loss. At the third stage LPP component portray that both positive and negative framing is supported by guilt emotion when processing emotional information in decision making. Our results delivered strong evidence that how purchase intention can be mediated by message framing under the pride and guilt emotions in the context of green marketing.

Background: Message framing plays an important role in advertising strategies and has been studied from various perspectives in different behavioral studies., New Method: This study employs the event-related potential technique to examine attentional and emotional brain processing as influenced by message framing in the context of green marketing., Results: The behavioral results demonstrated that purchase preference was higher under positive framing compared to negative and neutral framing.As per the event-related potential results, negative framing elicited a larger P1 component, which reveals that in the first stage of processing information, threatening information attracted more attention. In the second and third stage, N170 and P3, respectively, were higher for positive framing, demonstrating that there was more attention toward the processing of non-threatening emotional information.Comparison with existing method: Message Framing has been previously examined with behavioral methods. We for the first time examined it with a neuroscientific method like Event Related Brain Potential technique in a green marketing context., Conclusion: Our results compared to behavioral studies provide stronger evidence from underlying neural perspective for how message framing can be affected by attentional and emotional brain responses in the context of green marketing., (© 2020 The Author(s).)

The aim of this study was to screen the active regions and transcription factor binding sites in the promoter of the CBD103 gene related to Arctic fox coat color, and to provide a basis for revealing the molecular genetic mechanism of CBD103 gene regulating the coat color formation. The 5'-flanking region fragment 2 123 bp of Arctic fox CBD103 gene was cloned, and 4 truncated promoter reporter vectors of different lengths were constructed. The promoter activity was detected by the dual-luciferase reporter assay system. Point mutations were performed on the 3 predicted specificity protein 1 (Sp1) transcription factor binding sites in the highest promoter active region, and 3 mutant vectors were constructed. The activity was then detected by the dual-luciferase reporter assay system. The results showed that the region 1 656 (-1 604/+51) had the highest activity in the 4 truncated promoters of different lengths, and the promoter activity of the three mutant vectors constructed in this region were significantly lower than that of the wild type (fragment 1 656). The region of -1 604 /+51 was the core promoter region of CBD103 gene in Arctic fox and -1 552/-1 564, -1 439/-1 454 and -329/-339 regions were positive regulatory regions. This study successfully obtained the core promoter region and positive regulation regions of the Arctic fox CBD103 gene, which laid a foundation for further study on the molecular genetic mechanism of this gene regulating Arctic fox coat color.

Porcine reproductive and respiratory syndrome virus (PRRSV) has previously been shown to increase porcine 2'-5'-oligoadenylate synthase (OAS) 1a expression, but the specific role of porcine OAS1b (pOAS1b) in PRRSV replication remains unknown. In this study, we conducted sequence analysis of the porcine OAS1b gene and studied the effects of its overexpression or silencing on PRRSV replication. OAS1b, localized mainly in the cytoplasm, was found to contain conserved protein domains, such as the P-Loop and D-Box, indicating that its nucleotidyl transferase activity was complete and the antiviral effect depended on ribonuclease L (RNase L). OAS1b overexpression inhibited PRRSV replication, whereas small-interfering-RNA silencing of OAS1b resulted in increased virus titers. Additionally, OAS1b promoted expression of interferons as well as interferon-β promoter activity. These results lay the theoretical foundation for the development of new anti-PRRSV strategies., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Francisella tularensis causes a serious and often fatal infection, tularemia. We compared the efficacy of moxifloxacin formulated as free drug vs disulfide snap-top mesoporous silica nanoparticles (MSNs) in a mouse model of pneumonic tularemia. We found that MSN-formulated moxifloxacin was more effective than free drug and that the intramuscular and subcutaneous routes were markedly more effective than the intravenous route. Measurement of tissue silica levels and fluorescent flow cytometry assessment of colocalization of MSNs with infected cells revealed that the enhanced efficacy of MSNs and the intramuscular route of delivery was not due to better delivery of MSNs to infected tissues or cells. However, moxifloxacin blood levels demonstrated that the nanoparticle formulation and intramuscular route provided the longest half-life and longest time above the minimal inhibitory concentration. Thus, improved pharmacokinetics are responsible for the greater efficacy of nanoparticle formulation and intramuscular delivery compared with free drug and intravenous delivery.

Porcine 2',5'-oligoadenylate synthetase-like protein is an essential antiviral protein induced by interferons; however, its bioinformatics, genetic characteristics and immunological characteristics related to porcine reproductive and respiratory syndrome virus are still unknown. In this study, porcine 2',5'-oligoadenylate synthetase-like protein was cloned, and various attributes were predicted by bioinformatics analysis. Through RNAi depletion and overexpression methods, it was determined that porcine OASL not only inhibits porcine reproductive and respiratory virus replication but also activates interferon-beta production and the interferon-beta promoter, promoting the expression of interferon-beta mRNA. Through the depletion of different amino acids at the N and C termini, the antiviral activity and promoting the activity of interferon beta were evaluated. The results demonstrated that 31-60 amino acids at the N terminus were critical for virus replication. This study laid a theoretical foundation for exploring the characteristics of the porcine 2',5'-oligoadenylate synthetase-like protein and suggested a new strategy for the prevention and control of porcine reproductive and respiratory syndrome virus and investigation of the therapeutic mechanism of this protein., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

TWIST protein is critical to development and is activated in many cancers. TWIST regulates epithelial-mesenchymal transition, and is linked to angiogenesis, metastasis, cancer stem cell phenotype, and drug resistance. The majority of epithelial ovarian cancer (EOC) patients with metastatic disease respond well to first-line chemotherapy but most relapse with disease that is both metastatic and drug resistant, leading to a five-year survival rate under 20%. We are investigating the role of TWIST in mediating these relapses. We demonstrate TWIST-siRNA (siTWIST) and a novel nanoparticle delivery platform to reverse chemoresistance in an EOC model. Hyaluronic-acid conjugated mesoporous silica nanoparticles (MSN-HAs) carried siTWIST into target cells and led to sustained TWIST knockdown in vitro. Mice treated with siTWIST-MSN-HA and cisplatin exhibited specific tumor targeting and reduction of tumor burden. This platform has potential application for overcoming clinical challenges of tumor cell targeting, metastasis and chemoresistance in ovarian and other TWIST overexpressing cancers., (Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.)

Phase change materials such as pseudobinary GeTe-Sb 2 Te 3 (GST) alloys are an essential part of existing and emerging technologies. Here, we investigate the electrical and optical properties of epitaxial phase change materials: α-GeTe, Ge 2 Sb 2 Te5 (GST225), and Sb 2 Te 3 . Temperature-dependent Hall measurements reveal a reduction of the hole concentration with increasing temperature in Sb 2 Te 3 that is attributed to lattice expansion, resulting in a non-linear increase of the resistivity that is also observed in GST225. Fourier transform infrared spectroscopy at room temperature demonstrates the presence of electronic states within the energy gap for α-GeTe and GST225. We conclude that these electronic states are due to vacancy clusters inside these two materials. The obtained results shed new light on the fundamental properties of phase change materials such as the high dielectric constant and persistent photoconductivity and have the potential to be included in device simulations.

In Mycobacterium tuberculosis-infected macrophages, cyclooxygenase-2 (COX-2) expression considerably increases to defend the body against mycobacteria by regulating adaptive immunity and restoring the mitochondrial inner membrane. Moreover, in cancer cells, COX-2 enhances the autophagy machinery, an important bactericidal mechanism. However, the association between M. tuberculosis-induced COX-2 and autophagy-mediated antimycobacterial response has not been explored. Here, COX-2 expression silencing reduced the autophagy and bactericidal activity against intracellular M. tuberculosis, while COX-2 overexpression reversed the above effects. In addition, enhancement of bactericidal activity was suppressed by inhibiting autophagy in COX-2-overexpressing cells, indicating that COX-2 accelerated mycobacterial elimination by promoting autophagy. Furthermore, the regulatory effects of COX-2 on autophagy were mediated by its catalytic products, which functioned through inhibiting the protein kinase B/mammalian target of rapamycin pathway. Thus, COX-2 contributes to host defense against mycobacterial infection by promoting autophagy, establishing the basis for development of novel therapeutic agents against tuberculosis by targeting COX-2.

Objective: To study the relationship between HLA allele frequencies in peripheral blood mononuclear cells (PBMCs) and the susceptibility to tuberculosis in southern Chinese population., Methods: The polymorphisms of HLA-A and HLA-DRB1 loci in the PBMCs were analyzed in 294 patients with active tuberculosis using polymerase chain reaction-sequence based typing (PCT-SBT). The allele frequencies in the patients were compared with the data from 644 control southern Chinese subjects obtained from the online database Allele Frequencies in Worldwide Population., Results: The frequencies of HLA-A * 0101 and HLA-DRB1 * 1454 alleles in the patient cohort with pulmonary tuberculosis were significantly higher than those in the control group (2.4% vs 0.6%, χ 2 =10.788, P =0.001, P c =0.016; 7.5% vs 0%, χ 2 =69.850, P < 0.0001); the frequencies of HLA-DRB1 * 1202 and HLA-DRB1 * 1401 alleles were significantly lower in this patient cohort than in the control group (10.4% vs 16.1%, χ 2 =9.845, P =0.002, P c =0.044; 0% vs 3.1%, χ 2 =18.520, P < 0.001)., Conclusions: The frequencies of HLA-A and HLA-DRB1 alleles are correlated with the susceptibility to active tuberculosis in this southern Chinese population. HLA-A * 0101, HLA-DRB1 * 1454 and the other 3 alleles are likely susceptible genes to tuberculosis, while HLA-DRB1 * 1202, HLA-DRB1 * 1401 and the other 4 alleles can be protective genes in this population.

In this review we focus on methods that are used to trap and release on command therapeutic drugs from mesoporous silica nanoparticles (MSNs). The pores in the MSNs are large enough to accommodate a wide range of cargo molecules such as anticancer and antibiotic drugs and yet small enough to be blocked by a variety of bulky molecules that act as caps. The caps are designed to be tightly attached to the pore openings and trap the cargo molecules without leakage, but upon application of a designed stimulus detach from the nanoparticles and release the cargo. Of special emphasis in this review are nanomachines that respond to stimuli administered from external sources such as light or magnetic fields, or from chemical stimuli produced by the biological system such as a general change in pH or redox potential, or a highly specific chemical produced by a cancer cell or infectious bacterium. The goal is to release a high local concentration of the cargo only where and when it is needed, thus minimizing off-target side effects. We discuss sophisticated reversible nanomachines but also discuss some useful caps that simply break off from the nanoparticles in response to the selected stimulus. Many ingenious systems have been and are being designed; we primarily highlight those that have been demonstrated to operate in vitro and/or in vivo. In most cases the closed MSNs are endocytosed by diseased or infected cells and opened inside the cells to release the drugs. We begin with an overview of the nanoparticles and nanomachines and then present examples of drug release triggered by internal chemical stimuli from the organism and finally by external light and magnetic field stimuli., (© 2018 Elsevier Inc. All rights reserved.)

Phase-change materials based on GeSbTe show unique switchable optoelectronic properties and are an important contender for next-generation non-volatile memories. Moreover, they recently received considerable scientific interest, because it is found that a vacancy ordering process is responsible for both an electronic metal-insulator transition and a structural cubic-to-trigonal transition. GeTe-Sb 2 Te 3 based superlattices, or specifically their interfaces, provide an interesting platform for the study of GeSbTe alloys. In this work such superlattices have been grown with molecular beam epitaxy and they have been characterized extensively with transmission electron microscopy and X-ray diffraction. It is shown that the van der Waals gaps in these superlattices, which result from vacancy ordering, are mobile and reconfigure through the film using bi-layer defects and Ge diffusion upon annealing. Moreover, it is shown that for an average composition that is close to GeSb 2 Te 4 a large portion of 9-layered van der Waals systems is formed, suggesting that still a substantial amount of random vacancies must be present within the trigonal GeSbTe layers. Overall these results illuminate the structural organization of van der Waals gaps commonly encountered in GeSbTe alloys, which are intimately related to their electronic properties and the metal-insulator transition.

Epithelial ovarian cancer (EOC) is the most deadly gynecologic malignancy on account of its late stage at diagnosis and frequency of drug resistant recurrences. Novel therapies to overcome these barriers are urgently needed. TWIST is a developmental transcription factor reactivated in cancers and linked to angiogenesis, metastasis, cancer stem cell phenotype, and drug resistance, making it a promising therapeutic target. In this work, we demonstrate the efficacy of TWIST siRNA (siTWIST) and two nanoparticle delivery platforms to reverse chemoresistance in EOC models. Polyamidoamine dendrimers and mesoporous silica nanoparticles (MSNs) carried siTWIST into target cells and led to sustained TWIST knockdown in vitro. Mice treated with cisplatin plus MSN-siTWIST exhibited lower tumor burden than mice treated with cisplatin alone, with most of the effect coming from reduction in disseminated tumors. This platform has potential application for overcoming the clinical challenges of metastasis and chemoresistance in EOC and other TWIST overexpressing cancers., (Copyright © 2016 Elsevier Inc. All rights reserved.)