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DC-SIGN and Galectin-3 are two different lectins and have been reported to participate in regulation of several virus infections. WHO has pointed that H5N1 and H7N9 avian influenza viruses (AIVs) play continuous threats to global health. AIV hemagglutinin (HA) protein—a highly glycosylated protein—mediates influenza infection and was proposed to have DC-SIGN and Gal3 interactive domains. This study aims to address the individual and collaborative roles of DC-SIGN and Gal3 toward AIVs infection. Firstly, A549 cells with DC-SIGN expression or Gal3-knockdown, via lentiviral vector-mediated CD209 gene expression or LGALS-3 gene knockdown, respectively were generated. Quantitative reverse transcription PCR (qRT-PCR) results indicated that DC-SIGN expression and Gal3 knockdown in A549 cells significantly promoted and ameliorated HA or NP gene expression, respectively after H5N1 and H7N9-reverse genetics (RG) virus postinfections (P

Late initiation (LI) of combination antiretroviral therapy (cART)-defined as having a CD4This multicenter retrospective cohort study enrolled 1198 patients with newly diagnosed HIV infection during 2009-2019 who were grouped by status at cART initiation: those without LI (non-LI group, 56.01%); those with LI but without late presentation (LP) of HIV (LP: a CD4 + count of 200 cells/μL at HIV presentation or AIDS events ≤ 3 months of HIV diagnosis) [LILP(-) group, 4.51%]; and those with LI and with LP of HIV [LILP(+) group, 39.48%]. Joinpoint regression was used to identify changes in LI proportion.The median CD4Given the rise in LI from 2015 in the era of treat-all and rapid cART initiation, strategic interventions to increase earlier cART initiation must be intensified in Taiwan, especially among populations with delayed access to HIV testing services.

Background/Aims Vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is one of the best policies to control COVID-19 pandemic. The serological response to COVID-19 vaccination in Taiwanese patients with different comorbidities is elusive. Methods Uninfected subjects who received 3 doses of mRNA vaccines (BNT162b2 [Pfizer-BioNTech, BNT] and mRNA-1273 [Moderna]), viral vector-based vaccines (ChAdOx1-S (AZD1222, AZ) or protein subunit vaccines (Medigen COVID-19 vaccine) were prospectively enrolled. The SARS-CoV-2-IgG spike antibody level was determined within three months after the 3rd dose of vaccination. The Charlson Comorbidity Index (CCI) was applied to determine the association between vaccine titers and underlying comorbidities. Results A total of 824 subjects were enrolled in the current study. The proportions of CCI scores of 0-1, 2-3 and >4 were 52.8% (n=435), 31.3% (n=258) and 15.9% (n=131), respectively. The most commonly used vaccination combination was AZ-AZ-Moderna (39.2%), followed by Moderna-Moderna-Moderna (27.8%). The mean vaccination titer was 3.11 log BAU/mL after a median of 48 days after the 3rd dose. Factors associated with potentially effective neutralization capacity included an age ≥60 years (odds ratio [OR]/95% confidence interval [CI], 0.49/0.34–0.72; P β: 0.341, CI: 0.144, 0.21, P) and higher CCI scores (β: -0.055, CI: -0.096, -0.014, P=0.009) independently correlated with low IgG spike antibody levels. Conclusions Subjects with more comorbidities had a poor response to 3 doses of COVID-19 vaccination.

Many breast cancer patients harbor high estrogen receptor (ER) expression in tumors that can be treated with endocrine therapy, which includes aromatase inhibitors (AI); unfortunately, resistance often occurs. Mitochondrial dysfunction has been thought to contribute to progression and to be related to hormone receptor expression in breast tumors. Mitochondrial alterations in AI-resistant breast cancer have not yet been defined. In this study, we characterized mitochondrial alterations and their roles in AI resistance. MCF-7aro AI-resistant breast cancer cells were shown to have significant changes in mitochondria. Low expressions of mitochondrial genes and proteins could be poor prognostic factors for breast cancer patients. Long-term mitochondrial inhibitor treatments-mediated mitochondrial stress adaptation could induce letrozole resistance. ERα-amphiregulin (AREG) loop signaling was activated and contributed to mitochondrial stress adaptation-mediated letrozole resistance. The up-regulation of AREG-epidermal growth factor receptor (EGFR) crosstalk activated the PI3K/Akt/mTOR and ERK pathways and was responsible for ERα activation. Moreover, mitochondrial stress adaptation-increased intracellular levels of reactive oxygen species (ROS) and calcium were shown to induce AREG expression and secretion. In conclusion, our results support the claim that mitochondrial stress adaptation contributes to AI resistance via ROS/calcium-mediated AREG-ERα loop signaling and provide possible treatment targets for overcoming AI resistance.

BackgroundIntegrase strand transfer inhibitor (InSTI)-based regimens have become the major first-line treatment for HIV-1-infected patients in Taiwan. Transmitted drug resistance (TDR) and several clinical characteristics are associated with time to virological failure or viral suppression; however, these have not been investigated in Taiwan.ObjectivesTo determine the impact of several factors on treatment outcomes in HIV-1-infected patients in Taiwan.MethodsThe cohort included 164 HIV-1 treatment-naive patients in Taiwan from 2018 to 2020. Blood specimens were collected to determine the genotypic drug resistance using the Stanford University HIV drug resistance database. Cox proportional hazards models were used to identify factors associated with time to virological failure or viral suppression.ResultsThe prevalence of TDR in Taiwan was 27.4% and an increasing trend was seen from 2018 to 2020. TDR mutations related to NNRTIs were the most prevalent (21%) while TDR to InSTIs remained at a relatively low level (1.3%). A baseline HIV-1 viral load of ≥100 000 copies/mL was associated with a shorter time to virological failure [multivariate hazard ratio (mHR) 7.84; P = 0.018] and longer time to viral suppression (mHR 0.46; P ConclusionsThis study found an increasing trend of HIV-1 TDR prevalence from 2018 to 2020 in Taiwan. Baseline HIV-1 viral load and receiving InSTI-based regimens are important factors associated with time to virological failure or viral suppression.

Recently, the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) was quickly identified as the causal pathogen leading to the outbreak of SARS-like illness all over the world. As the SARS-CoV-2 infection pandemic proceeds, many efforts are being dedicated to the development of diverse treatment strategies. Increasing evidence showed potential therapeutic agents directly acting against SARS-CoV-2 virus, such as interferon, RNA-dependent RNA polymerase inhibitors, protease inhibitors, viral entry blockers, neuraminidase inhibitor, vaccine, antibody agent targeting the SARS-CoV-2 RNA genome, natural killer cells, and nucleocytoplasmic trafficking inhibitor. To date, several direct anti-SARS-CoV-2 agents have demonstrated promising in vitro and clinical efficacy. This article reviews the current and future development of direct acting agents against SARS-CoV-2.

The papers published in this Special Issue include various essential steps and regulatory mechanisms involved in viral protein synthesis, protein processing, glycosylation, and assembly [...]

Galectin-3 (GAL3) is a β-galactoside-binding lectin expressed in CD4 T cells infected with human immunodeficiency virus-1 (HIV-1). GAL3 promotes HIV-1 budding by associating with ALIX and Gag p6. GAL3 has been shown to localize in membrane lipid rafts in dendritic cells and positively regulate cell migration. HIV-1 spreads between T cells by forming supramolecular structures (virological synapses [VSs]), whose integrity depends on lipid rafts. Here, we addressed the potential role of GAL3 in cell-to-cell transmission of HIV-1 in CD4 T cells. GAL3 expressed in donor cells was more important for facilitating HIV-1 cell-to-cell transfer than GAL3 expressed in target cells. GAL3 was found to be co-transferred with Gag from HIV-1-positive donor to HIV-1-negative target T cells. HIV-1 infection induced translocation of GAL3 together with Gag to the cell–cell interfaces and colocalize with GM1, where GAL3 facilitated VS formation. GAL3 regulated the coordinated transfer of Gag and flotillin-1 into plasma membrane fractions. Finally, depletion of GAL3 reduced the cholesterol levels in membrane lipid rafts in CD4 T cells. These findings provide evidence that endogenous GAL3 stimulates lipid raft components and facilitates intercellular HIV-1 transfer among CD4 T cells, offering another pathway by which GAL3 regulates HIV-1 infection. These findings may inform the treatment of HIV-1 infection based on targeting GAL3 to modulate lipid rafts.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus emerged in late 2019 leading to the COVID-19 disease pandemic that triggered socioeconomic turmoil worldwide. A precise, prompt, and affordable diagnostic assay is essential for the detection of SARS-CoV-2 as well as its variants. Antibody against SARS-CoV-2 spike (S) protein was reported as a suitable strategy for therapy and diagnosis of COVID-19. We, therefore, developed a quick and precise phase-sensitive surface plasmon resonance (PS-SPR) biosensor integrated with a novel generated anti-S monoclonal antibody (S-mAb). Our results indicated that the newly generated S-mAb could detect the original SARS-CoV-2 strain along with its variants. In addition, a SARS-CoV-2 pseudovirus, which could be processed in BSL-2 facility was generated for evaluation of sensitivity and specificity of the assays including PS-SPR, homemade target-captured ELISA, spike rapid antigen test (SRAT), and quantitative reverse transcription polymerase chain reaction (qRT-PCR). Experimentally, PS-SPR exerted high sensitivity to detect SARS-CoV-2 pseudovirus at 589 copies/ml, with 7-fold and 70-fold increase in sensitivity when compared with the two conventional immunoassays, including homemade target-captured ELISA (4 × 10

Dengue is one of the most prevalent infectious diseases in the world. Rapid, accurate and scalable diagnostics are key to patient management and epidemiological surveillance of the dengue virus (DENV), however current technologies do not match required clinical sensitivity and specificity or rely on large laboratory equipment. In this work, we report the translation of our smartphone-connected handheld Lab-on-Chip (LoC) platform for the quantitative detection of two dengue serotypes. At its core, the approach relies on the combination of Complementary Metal-Oxide-Semiconductor (CMOS) microchip technology to integrate an array of 78 × 56 potentiometric sensors, and a label-free reverse-transcriptase loop mediated isothermal amplification (RT-LAMP) assay. The platform communicates to a smartphone app which synchronises results in real time with a secure cloud server hosted by Amazon Web Services (AWS) for epidemiological surveillance. The assay on our LoC platform (RT-eLAMP) was shown to match performance on a gold-standard fluorescence-based real-time instrument (RT-qLAMP) with synthetic DENV-1 and DENV-2 RNA and extracted RNA from 9 DENV-2 clinical isolates, achieving quantitative detection in under 15 min. To validate the portability of the platform and the geo-tagging capabilities, we led our study in the laboratories at Imperial College London, UK, and Kaohsiung Medical Hospital, Taiwan. This approach carries high potential for application in low resource settings at the point of care (PoC).

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike (S) glycoprotein D614G mutation became the predominant globally circulating variant after its emergence in the early coronavirus disease 2019 (COVID-19) pandemic. Studies showed that this mutation results in an open conformation of the S glycoprotein receptor-binding domain (RBD), and increased angiotensin 1-converting enzyme 2 (ACE2) binding and fusion, which result in an increase in SARS-CoV-2 transmissibility and infectivity. Dynamic tracking of SARS-CoV-2 showed that the D614G variant became predominant after emergence in Europe and North America, but not in China. The current absence of selective pressures from antiviral treatment suggests that the driving force for viral evolution could be variations in human population genetics. Results show that ACE2 expression is higher in Asian populations than that in European, North American, and African populations. This supports the idea that lower ACE2 expression is a driving force in the positive selection for the D614G mutation. This study suggests that the dynamics of the SARS-CoV-2 D614G mutation during the early-to-mid pandemic is associated with enhanced transmission efficiency in populations with lower ACE2 expression. Understanding the role that human genetic diversity plays in the adaptive evolution of SARS-CoV-2 may have an important impact on public health and measures to control the pandemic.

Dengue virus (DENV) is a global health threat causing about half of the worldwide population to be at risk of infection, especially the people living in tropical and subtropical area. Although the dengue disease caused by dengue virus (DENV) is asymptomatic and self-limiting in most people with first infection, increased severe dengue symptoms may be observed in people with heterotypic secondary DENV infection. Since there is a lack of specific antiviral medication, the development of dengue vaccines is critical in the prevention and control this disease. Several targets and strategies in the development of dengue vaccine have been demonstrated. Currently, Dengvaxia, a live-attenuated chimeric yellow-fever/tetravalent dengue vaccine (CYD-TDV) developed by Sanofi Pasteur, has been licensed and approved for clinical use in some countries. However, this vaccine has demonstrated low efficacy in children and dengue-naïve individuals and also increases the risk of severe dengue in young vaccinated recipients. Accordingly, many novel strategies for the dengue vaccine are under investigation and development. Here, we conducted a systemic literature review according to PRISMA guidelines to give a concise overview of various aspects of the vaccine development process against DENVs, mainly targeting five potential strategies including live attenuated vaccine, inactivated virus vaccine, recombinant subunit vaccine, viral-vector vaccine, and DNA vaccine. This study offers the comprehensive view of updated information and current progression of immunogen selection as well as strategies of vaccine development against DENVs.

Healthcare workers (HCWs) are on the frontline fighting several infectious diseases including SARS-CoV-1 and COVID-19. Coronavirus neutralizing antibodies (nAbs) were recently reported to last for a certain period. The factors affecting nAbs’ existence remain unclear. Here, we retrospectively analyzed the factors correlating with nAbs’ from SARS-CoV-1 long-term convalescence HCWs in Taiwan. One hundred and thirty SARS-CoV-1 convalescent patients were recruited between August 2006 and March 2007. Blood samples were collected to determine the anti-nucleocapsid (N) and anti-spike (S) antibodies’ existence status and neutralization ability. Neutralization ability was measured using SARS-CoV-1 pseudotyped viruses. Statistical analysis of factors associated with anti-SARS-CoV-1 antibodies’ existence status was determined using SAS software. 46.2% SARS-CoV-1 convalescent patients presented anti-N antibody after three years post-infection. Among sixty participants, ten participants co-presented anti-S antibodies. Eight participants with anti-S antibody displayed neutralization ability to SARS-CoV-1. The gender, age, and disease severity of participants did not affect the anti-N antibody existence status, whereas the anti-S antibody is significantly reduced in participants with old age (>50 years, p = 0.0434) after three years post SARS-CoV-1 infection. This study suggests that age is an important factor correlated with the duration of SARS-CoV-1 protective antibody existence status.

Cancer cells have the metabolic flexibility to adapt to heterogeneous tumor microenvironments. The integrated stress response (ISR) regulates the cellular adaptation response during nutrient stress. However, the issue of how the ISR regulates metabolic flexibility is still poorly understood. In this study, we activated the ISR using salubrinal in cancer cells and found that salubrinal repressed cell growth, colony formation, and migration but did not induce cell death in a glucose-containing condition. Under a glucose-deprivation condition, salubrinal induced cell death and increased the levels of mitochondrial reactive oxygen species (ROS). We found that these effects of salubrinal and glucose deprivation were associated with the upregulation of xCT (SLC7A11), which functions as an antiporter of cystine and glutamate and maintains the level of glutathione to maintain redox homeostasis. The upregulation of xCT did not protect cells from oxidative stress-mediated cell death but promoted it during glucose deprivation. In addition, the supplementation of ROS scavenger N-acetylcysteine and the maintenance of intracellular levels of amino acids via sulfasalazine (xCT inhibitor) or dimethyl-α-ketoglutarate decreased the levels of mitochondrial ROS and protected cells from death. Our results suggested that salubrinal enhances cancer cell death during glucose deprivation through the upregulation of xCT and mitochondrial oxidative stress.

Throughout history, infectious diseases have vastly impacted human civilization [...]

Animal lectins are proteins with carbohydrate recognition activity. Galectins, the β-galactoside binding lectins, are expressed in various cells and have been reported to regulate several immunological and physiological responses. Recently, some galectins have been reported to regulate some viral infections, including influenza A virus (IAV); however, the mechanism is still not fully understood. Thus, we aim to review systemically the roles of galectins in their antiviral functions against IAVs. The PRISMA guidelines were used to select the eligible articles. Results indicated that only Galectin-1, Galectin-3, and Galectin-9 were reported to play a regulatory role in IAV infection. These regulatory effects occur extracellularly, through their carbohydrate recognition domain (CRD) interacting with glycans expressed on the virus surface, as well as endogenously, in a cell–cell interaction manner. The inhibition effects induced by galectins on IAV infection were through blocking virus–host receptors interaction, activation of NLRP-3 inflammasome, augment expression of antiviral genes and related cytokines, as well as stimulation of Tim-3 related signaling to enhance virus-specific T cells and humoral immune response. Combined, this study concludes that currently, only three galectins have reported antiviral capabilities against IAV infection, thereby having the potential to be applied as an alternative anti-influenza therapeutic strategy.

Galectins, are β-galactoside binding lectins expressed in numerous cells and are known to regulate various immune responses and cellular physiological functions. Galectins have been reported to participate in the regulation of several viral infections via carbohydrate‑dependent/independent manner. Galectins have displayed various regulatory functions on viral infection, however, the detailed mechanism remains unclear. More recently, some members of galectins have been reported to regulate influenza A virus (IAV) infection. In this review, we aim to analyze and summarize current findings regarding the role of galectins in IAV infection and their antiviral potential therapeutic application in the treatment of IAVs. The eligible articles were selected according to the PRISMA guidelines. Results indicate that Galectin-1(Gal-1), Galectin-3(Gal-3) and Galectin-9 (Gal-9) were found as the predominant galectins reported to participate in the regulation of IAVs infection. The inhibitory regulation of IAVs by these galectins occurred mainly through extracellular binding to glycosylated envelope proteins, further blocking the interaction between influenza envelope and sialic acid receptor, interacting with ligands or receptors on immune cells to trigger immunol or cellular response against IAVs, and endogenously interacting cellular components in the cytoplasm to activate inflammasome and autophagy. This study offers information regarding the multiple roles of galectins observed in IAVs infection and suggest that galectins has the potential to be used as therapeutic agents for IAVs.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has evolved to display particular patterns of genetic diversity in the genome across geographical regions. These variations in the virus and genetic variation in human populations can determine virus transmissibility and coronavirus disease 2019 (COVID-19) severity. Genetic variations and immune differences in human populations could be the driving forces in viral evolution. Recently emerged SARS-CoV-2 variants show several mutations at the receptor binding domain in the spike (S) glycoprotein and contribute to immune escape and enhanced binding with angiotensin 1-converting enzyme 2 (ACE2). Since ACE2 and transmembrane protease serine 2 (TMPRSS2) play important roles in SARS-CoV-2 entry into the cell, genetic variation in these host entry-related proteins may be a driving force for positive selection in the SARS-CoV-2 S glycoprotein. Dendritic or liver/lymph cell-specific intercellular adhesion molecule (ICAM)-3-grabbing non-integrin is also known to play vital roles in several pathogens. Genetic variations of these host proteins may affect the susceptibility to SARS-CoV-2. This review summarizes the latest research to describe the impacts of genetic variation in the viral S glycoprotein and critical host proteins and aims to provide better insights for understanding transmission and pathogenesis and more broadly for developing vaccine/antiviral drugs and precision medicine strategies, especially for high risk populations with genetic risk variants.

DC-SIGN, a C-type lectin mainly expressed in dendritic cells (DCs), has been reported to mediate several viral infections. We previously reported that DC-SIGN mediated H5N1 influenza A virus (AIVs) infection, however, the important DC-SIGN interaction with N-glycosylation sites remain unknown. This study aims to identify the optimal DC-SIGN interacting N-glycosylation sites in HA proteins of H5N1-AIVs. Results from NetNGlyc program analyzed the H5 hemagglutinin sequences of isolates during 2004&ndash, 2020, revealing that seven and two conserved N-glycosylation sites were detected in HA1 and HA2 domain, respectively. A lentivirus pseudotyped A/Vietnam/1203/04 H5N1 envelope (H5N1-PVs) was generated which displayed an abundance of HA5 proteins on the virions via immuno-electron microscope observation. Further, H5N1-PVs or reverse-genetics (H5N1-RG) strains carrying a serial N-glycosylated mutation was generated by site-directed mutagenesis assay. Human recombinant DC-SIGN (rDC-SIGN) coated ELISA showed that H5N1-PVs bound to DC-SIGN, however, mutation on the N27Q, N39Q, and N181Q significantly reduced this binding (p &lt, 0.05). Infectivity and capture assay demonstrated that N27Q and N39Q mutations significantly ameliorated DC-SIGN mediated H5N1 infection. Furthermore, combined mutations (N27Q&amp, N39Q) significantly waned the interaction on either H5N1-PVs or -RG infection in cis and in trans (p &lt, 0.01). This study concludes that N27 and N39 are two essential N-glycosylation contributing to DC-SIGN mediating H5N1 infection.

Carbapenem-resistant Enterobacteriaceae (CRE) is listed as an urgent threat by the World Health Organization because of the limited therapeutic options, rapid evolution of resistance mechanisms, and worldwide dissemination. Colistin is a common backbone agent among the &ldquo, last-resort&rdquo, antibiotics for CRE, however, its emerging resistance among CRE has taken the present dilemma to the next level. Azidothymidine (AZT), a thymidine analog used to treat human immunodeficiency virus/acquired immunodeficiency syndrome, has been known to possess antibacterial effects against Enterobacteriaceae. In this study, we investigated the combined effects of AZT and colistin in 40 clinical isolates of colistin-resistant, carbapenem-resistant K. pneumoniae (CCRKP). Eleven of the 40 isolates harbored Klebsiella pneumoniae carbapenemase. The in vitro checkerboard method and in vivo nematode killing assay both revealed synergistic activity between the two agents, with fractional inhibitory concentration indexes of &le, 0.5 in every strain. Additionally, a significantly lower hazard ratio was observed for the nematodes treated with combination therapy (0.288, p &lt, 0.0001) compared with either AZT or colistin treatment. Toxicity testing indicated potentially low toxicity of the combination therapy. Thus, the AZT&ndash, colistin combination could be a potentially favorable therapeutic option for treating CCRKP.

Increasing carbapenem resistance rates worldwide underscored the urgent need of novel antimicrobials. Ceftazidime&ndash, avibactam and aztreonam&ndash, avibactam combinations are developed to combat carbapenem resistance, but biological and geographic variations must be considered for antibiotic susceptibility patterns varied. Thus, we sought to assess the susceptibilities of ceftazidime&ndash, avibactam against 660 carbapenem-nonsusceptible Enterobacteriaceae isolates (472 Klebsiella pneumoniae and 188 Escherichia coli) collected during an earlier Taiwan surveillance study. Agar dilution method was used to determine ceftazidime&ndash, avibactam susceptibility. Metallo-carbapenemase&rsquo, s contribution to resistance were investigated with EDTA addition. The in vivo efficacies were evaluated using a Caenorhabditis elegans model. High susceptibility rates were observed for ceftazidime&ndash, avibactam against the 472 carbapenem-nonsusceptible K. pneumoniae (CnsKP) (85.2% and 95.3%, respectively) and 188 carbapenem-nonsusceptible E. coli (CnsEC) isolates (91.5% and 94.1%, respectively). For non-metallo-carbapenemase producers, the susceptibility rates for ceftazidime&ndash, avibactam were 93.6% for CnsKP and 97.7% for CnsEC, whereas only 7.1% CnsKP and 11.1% CnsEC in metallo-carbapenemase producers were susceptible to ceftazidime&ndash, avibactam. Of all isolates, 95.3% CnsKP and 94.1% CnsEC were susceptible to aztreonam&ndash, avibactam. In C. elegans model, ceftazidime&ndash, avibactam revealed effective against a blaKPC-producing K. pneumoniae isolate in vivo. Our results propose a positive therapeutic approach for both combinations against carbapenem-nonsusceptible Enterobacteriaceae in Taiwan.

Since the H7N9 avian influenza virus emerged in China in 2013, there have been five seasonal waves which have shown human infections and caused high fatality rates in infected patients. A multibasic amino acid insertion seen in the HA of current H7N9 viruses occurred through natural evolution and reassortment, and created a high pathogenicity avian influenza (HPAI) virus from the low pathogenicity avian influenza (LPAI) in 2017, and significantly increased pathogenicity in poultry, resulting in widespread HPAI H7N9 in poultry, which along with LPAI H7N9, contributed to the severe fifth seasonal wave in China. H7N9 is a novel reassorted virus from three different subtypes of influenza A viruses (IAVs) which displays a great potential threat to public health and the poultry industry. To date, no sustained human-to-human transmission has been recorded by the WHO. However, the high ability of evolutionary adaptation of H7N9 and lack of pre-existing immunity in humans heightens the pandemic potential. Changes in IAVs proteins can affect the viral transmissibility, receptor binding specificity, pathogenicity, and virulence. The multibasic amino acid insertion, mutations in hemagglutinin, deletion and mutations in neuraminidase, and mutations in PB2 contribute to different virological characteristics. This review summarized the latest research evidence to describe the impacts of viral protein changes in viral adaptation and pathogenicity of H7N9, aiming to provide better insights for developing and enhancing early warning or intervention strategies with the goal of preventing highly pathogenic IAVs circulation in live poultry, and transmission to humans.

The immunopathogenesis of H5N1 virus has been studied intensively since it caused cross-species infection and induced high mortality to human. We previously observed the interaction between monocytes and B cells, which increased the susceptibility of B cell to H5N1 virus infection after a co-culture. Levels of α2,3 sialic acid (avian flu receptor) were also significantly increased on B cell surface in this co-culture model with unclear explanation. In this study, we aimed to determine the possible mechanism that responded for this increase in α2,3 sialic acid on B cells. Acquisition of α2,3 SA by B cells via cell contact-dependent trogocytosis was proposed. Results showed that the lack of α2,3 SA was detected on B cell surface, and B cells acquired membrane-bound α2,3 SA molecules from monocytes in H5N1-infected co-cultures. Occurrence of membrane exchange mainly relied on H5N1 infection and cell-cell contact as opposed to a mock infection and transwell. The increase in α2,3 SA on B cell surface mediated by trogocytosis was associated with the enhanced susceptibility to H5N1 infection. These observations thus provide the evidence that H5N1 influenza virus may utilize trogocytosis to expand its cell tropism and spread to immune cells despite the lack of avian flu receptor.

As the coronavirus disease 2019 (COVID-19, also called severe acute respiratory syndrome coronavirus-2) outbreak accelerates, vigorous and diverse efforts were made in developing treatment strategies. In addition to direct acting agents, increasing evidence showed some potential adjuvant therapies with promising efficacy against COVID-19. These therapies include immunomodulators (i.e. intravenous immunoglobulin, thymosin α-1, interleukin [IL]-6, tocilizumab, cyclosporine, thalidomide, fingolimod), Chinese medicines (i.e. glycyrrhizin, baicalin, Xuebijing), anti-vascular endothelial growth factors (bevacizumab), estrogen modulating drugs, statins, and nutritional supplements (i.e. vitamins A, B, C, D, E and zinc). This article reviewed the pharmacological development of potential adjuvants for COVID-19 treatment.

Mitochondria are important organelles that are responsible for cellular energy metabolism, cellular redox/calcium homeostasis, and cell death regulation in mammalian cells. Mitochondrial dysfunction is involved in various diseases, such as neurodegenerative diseases, cardiovascular diseases, immune disorders, and cancer. Defective mitochondria and metabolism remodeling are common characteristics in cancer cells. Several factors, such as mitochondrial DNA copy number changes, mitochondrial DNA mutations, mitochondrial enzyme defects, and mitochondrial dynamic changes, may contribute to mitochondrial dysfunction in cancer cells. Some lines of evidence have shown that mitochondrial dysfunction may promote cancer progression. Here, several mitochondrial stress responses, including the mitochondrial unfolded protein response and the integrated stress response, and several mitochondrion-derived molecules (reactive oxygen species, calcium, oncometabolites, and others) are reviewed; these pathways and molecules are considered to act as retrograde signaling regulators in the development and progression of cancer. Targeting these components of the mitochondrial stress response may be an important strategy for cancer treatment.Impact statementDysregulated mitochondria often occurred in cancers. Mitochondrial dysfunction might contribute to cancer progression. We reviewed several mitochondrial stresses in cancers. Mitochondrial stress responses might contribute to cancer progression. Several mitochondrion-derived molecules (ROS, Ca2+, oncometabolites, exported mtDNA, mitochondrial double-stranded RNA, humanin, and MOTS-c), integrated stress response, and mitochondrial unfolded protein response act as retrograde signaling pathways and might be critical in the development and progression of cancer. Targeting these mitochondrial stress responses may be an important strategy for cancer treatment.

Background Epidemiology of fosfomycin susceptibility and the plasmid-mediated fosfomycinase genes of carbapenem-resistant Klebsiella pneumoniae (CRKP) isolates in Taiwan remain unclear. Methods 642 CRKP clinical isolates were collected from a nation-wide surveillance study (16 hospitals) in Taiwan in 2012–2013. Antimicrobial susceptibilities were determined. PFGE and MLST determined the clonal relatedness. Carbapenemases and fosfomycinases genes were detected by PCR, and their flanking regions were determined by PCR and sequencing. Synergistic activity of meropenem with fosfomycin was examined by the checkerboard method. Results In total, 36.4% (234/642) of CRKP isolates in Taiwan were resistant to fosfomycin. Among 234 fosfomycin-resistant CRKP isolates, PFGE analysis revealed 81 pulsotypes. Pulsotype XXIII (n = 63) was predominant and belonged to ST11. 71 had carbapnemases (65 bla KPC-2 -positive, 1 bla VIM-1 -positive and 5 bla IMP-8 -positive) and 62 had fosfomycinases (35 fosA3 -positive and 27 foskp96 -positive). Only 18.5% (5/27) of foskp96 -positive isolates carried foskp96 and bla KPC-2 , while 71.4% (25/35) of fosA3 -positive isolates contained fosA3 and bla KPC-2 . There were five types of flanking sequences for fosA3 , and 85.7% (30/35) of fosA3 genes were flanked by IS 26 , suggesting possible horizontal gene transfer. Synergistic effect of fosfomycin and meropenem was observed in all 25 randomly selected pulsotype XXIII strains (100%; 25/25), even those containing fosfomycinase (48%, 12/25) or carbapnemase (96%, 24/25). Conclusions A clone (pulsotype XXIII, ST11) has been found to be prevailing among fosfomycin-resistant CRKP in Taiwan. According to the in vitro data, the combination of fosfomycin and meropenem is a potentially alternative choice.

// Chun-Wei Wang 1, 2 , Chiung-Chiao Huang 1 , Pei-Hsin Chou 4 , Yu-Ping Chang 1 , Shouzuo Wei 5 , Frederick Peter Guengerich 6 , Yueh-Ching Chou 3, 7, 9 , Sheng-Fan Wang 1, 7 , Ping-Shan Lai 8 , Pavel Soucek 11 and Yune-Fang Ueng 1, 2, 3, 10 1 National Research Institute of Chinese Medicine, Ministry of Health and Welfare, Taipei, Taiwan, R.O.C 2 Institute of Biopharmaceutical Sciences, School of Pharmacy, National Yang-Ming University, Taipei, Taiwan, R.O.C 3 Department of Pharmacology, School of Medicine, National Yang-Ming University, Taipei, Taiwan, R.O.C 4 Department of Environmental Engineering, National Chung-Kung University, Tainan, Taiwan, R.O.C 5 Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, USA 6 Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, USA 7 Department of Pharmacy, Taipei Veterans General Hospital, Taipei, Taiwan, R.O.C 8 Department of Chemistry, College of Science, National Chung-Hsin University, Taichung, Taiwan, R.O.C 9 Department of Pharmacy, Taipei Medical University, Taipei, Taiwan, R.O.C 10 Institute of Medical Sciences, Taipei Medical University, Taipei, Taiwan, R.O.C 11 Department of Toxicogenomics, National Institute of Public Health, Prague, Czech Republic Correspondence to: Yune-Fang Ueng, email: ueng@nricm.edu.tw Keywords: 7-ketocholesterol, 27-hydroxycholesterol, doxorubicin, P-glycoprotein, estrogen receptor Received: March 13, 2017 Accepted: June 27, 2017 Published: August 02, 2017 ABSTRACT Hypercholesterolemia is one of the risk factors for poor outcome in breast cancer therapy. To elucidate the influence of the main circulating oxysterols, cholesterol oxidation products, on the cell-killing effect of doxorubicin, cells were exposed to oxysterols at a subtoxic concentration. When cells were exposed to oxysterols in fetal bovine serum-supplemented medium, 7-ketocholesterol (7-KC), but not 27-hydroxycholesterol (27-HC), decreased the cytotoxicity of doxorubicin in MCF-7 (high estrogen receptor (ER)α/ERβ ratio) cells and the decreased cytotoxicity was restored by the P-glycoprotein inhibitor verapamil. 7-KC stimulated the efflux function of P-glycoprotein and reduced intracellular doxorubicin accumulation in MCF-7 but not in ERα(-) MDA-MB-231 and the resistant MCF-7/ADR cells. In MCF-7 cells, 7-KC increased the mRNA and protein levels of P-glycoprotein. The 7-KC-suppressed doxorubicin accumulation was restored by the fluvestrant and ERα knockdown. In a yeast reporter assay, the ERα activation by 7-KC was more potent than 27-HC. 7-KC, but not 27-HC, stimulated the expression of an ER target, Trefoil factor 1 in MCF-7 cells. When charcoal-stripped fetal bovine serum was used, both 7-KC and 27-HC induced Trefoil factor 1 expression and reduced doxorubicin accumulation in MCF-7 cells. 7-KC-reduced doxorubicin accumulation could be reversed by inhibitors of phosphatidylinositol 3-kinase, Akt, and mammalian target of rapamycin (mTOR). These findings demonstrate that 7-KC decreases the cytotoxicity of doxorubicin through the up-regulation of P-glycoprotein in an ERα- and mTOR-dependent pathway. The 7-KC- and 27-HC-elicited estrogenic effects are crucial in the P-glycoprotein induction in breast cancer cells.

HIV-1 CRF07_BC is a recombinant virus with amino acid (a.a.) deletions in p6Gag, which are overlapped with the Alix-binding domain. Galectin-3 (Gal3), a β-galactose binding lectin, has been reported to interact with Alix and regulate HIV-1 subtype B budding. This study aims to evaluate the role of Gal3 in HIV-1 CRF07_BC infection and the potential effect of a.a. deletions on Gal3-mediated regulation. A total of 38 HIV-1+ injecting drug users (IDUs) were enrolled in the study. Viral characterization and correlation of Gal3 were validated. CRF07_BC containing 7 a.a. deletions and wild-type in the p6Gag (CRF07_BC-7d and -wt) were isolated and infectious clones were generated. Viral growth kinetic and budding assays using Jurkat-CCR5/Jurkat-CCR5-Gal3 cells infected with CRF07_BC were performed. Results indicate that 69.4% (25/38) of the recruited patients were identified as CRF07_BC, and CRF07_BC-7d was predominant. Slow disease progression and significantly higher plasma Gal3 were noted in CRF07_BC patients (p < 0.01). Results revealed that CRF07_BC infection resulted in Gal3 expression, which was induced by Tat. Growth dynamic and budding assays indicated that Gal3 expression in Jurkat-CCR5 cells significantly enhanced CRF07_BC-wt replication and budding (p < 0.05), while the promoting effect was ameliorated in CRF07_BC-7d. Co-immunoprecipitation found that deletions in the p6Gag reduced Gal-3-mediated enhancement of the Alix–Gag interaction.

Galectins are differentially expressed in a variety of cell types, including immune cells, and characterized by the affinity for β-galactoside–containing glycans. There are fifteen galectin members in mammals. Galectins are primarily located intracellularly, but can be secreted outside the cells. They exhibit pivotal roles during microbial infection, such as pathogen recognition and innate and adaptive immunity, and this review aims to discuss the functions of endogenous galectins during infection by four main types of microbes (bacteria, fungi, viruses, and parasites). Extracellular galectins are known to exert a bacteriostatic effect on some bacteria via association with bacterial glycans, whereas cytosolic galectins are recognized to control antibacterial autophagy by binding to luminal host glycans of ruptured endo-lysosomes. With regard to fungal infections, most studies deal with galectin-3. Galectin-3 modulates fungal burdens, the adaptive immune responses, and mortality in fungi-infected mice, which has been shown to be associated with its ability to manipulate fungicidal functions in neutrophils and cytokine expression in dendritic cells. Some viral infections, such as human immunodeficiency virus (HIV) and influenza virus infections, can be regulated by galectin-1 and -3, and they affect various aspects of viral infections, including viral binding, replication, budding, transmission, and infection-associated inflammation. Functions of galectins during a number of different parasitic infections have been identified in studies using galectin-knockout mice. Different parasitic infections have consistently demonstrated a role of galectins in tuning T helper immune responses in infected hosts.

Objectives: This study was performed to examine the current status of Zika and the effects of pre-existing dengue immunity on Zika virus (ZIKV) infection in Southern Taiwan. Methods: A phylogenetic tree was used to analyze the phylogeny of detected ZIKVs. Paired sera from dengue patients were collected for the determination of dengue and Zika infection. Plaque reduction neutralization tests (PRNT) and quantitative reverse transcription PCR (qRT-PCR) were used to determine the titers of neutralizing antibodies and viruses, respectively. An antibody-dependent enhancement (ADE) assay was used to evaluate the effect of anti-dengue antibodies on ZIKV infection. Results: Epidemiological data indicated the continuous importation of ZIKV infection from neighboring Zika epidemic countries into Taiwan. A total of 78 dengue patients were enrolled and 21 paired serum samples were obtained. PRNT90 results for the 21 samples identified eight cases of primary dengue infection and 13 cases of secondary dengue infection; two samples were positive for ZIKV (MR766). Results from the ADE assay indicated that convalescent sera from primary and secondary dengue infection patients displayed significant ADE of the ZIKV infection when compared to healthy controls (p < 0.05). Conclusions: This study suggests that pre-existing dengue immunity facilitates ZIKV infection and that the continuous importation of ZIKV infection may pose a threat to indigenous Zika emergence in Southern Taiwan. Keywords: Zika, Dengue, Importation, Taiwan, Antibody-dependent enhancement, Plaque reduction neutralization test

Objectives: This study examined the epidemiological, clinical, and immunological characteristics of the 2015 dengue outbreak in Taiwan. Methods: Clinical data were collected from dengue fever (DF) and dengue hemorrhagic fever (DHF) patients. A phylogenetic tree was used to analyze the source of the outbreak strain. Paired plasma samples from DF/DHF patients were used for antibody-dependent enhancement (ADE) assay and cytokine multiplex biometric immunoassay to validate the immunological mechanism. Results: This outbreak mainly occurred in two of the southern cities of Taiwan: Tainan (n = 22 777; 52%) and Kaohsiung (n = 19 784; 45%). A high DHF death rate was noted (34.6%). The case (DHF) and control (DF) study indicated that older age (>60 years), type II diabetes, and hypertension were risk factors correlated with the development of DHF (p

Background Galectins are β-Galactose binding lectins expressed in numerous cells and play multiple roles in various physiological and cellular functions. However, few information is available regarding the role of galectins in virus infections. Here, we conducted a systemic literature review to analyze the role of galectins in human virus infection. Methods This study uses a systematic method to identify and select eligible articles according to the PRISMA guidelines. References were selected from PubMed, Web of Science and Google Scholar database covering publication dated from August 1995 to December 2018. Results Results indicate that galectins play multiple roles in regulation of virus infections. Galectin-1 (Gal-1), galectin-3 (Gal-3), galectin-8 (Gal-8), and galectin-9 (Gal-9) were found as the most predominant galectins reported to participate in virus infection. The regulatory function of galectins occurs by extracellularly binding to viral glycosylated envelope proteins, interacting with ligands or receptors on immune cells, or acting intracellularly with viral or cellular components in the cytoplasm. Several galectins express either positive or negative regulatory role, while some had dual regulatory capabilities on virus propagation based on the conditions and their localization. However, limited information about the endogenous function of galectins were found. Therefore, the endogenous effects of galectins in host-virus regulation remains valuable to investigate. Conclusions This study offers information regarding the various roles galectins shown in viral infection and suggest that galectins can potentially be used as viral therapeutic targets or antagonists.

Breast cancer patients with high cholesterol biosynthesis signature had poorer therapeutic outcome. Cytochrome P450 (CYP) 2D6 is crucial in the oxidation of tamoxifen to generate active metabolites, 4-hydroxytamoxifen and endoxifen. CYP2D6 variants with C100T substitution encode null or poor functional proteins. This study aims to examine the association of C100T genotypes and serum lipid levels with plasma drug levels in patients. Plasma tamoxifen concentration was positively associated with serum triglyceride concentration, adjusting for age and C100T genotype. Overweight (body mass index24.0) patients with high serum cholesterol (≥200 mg/dL) had increased risks of ineffective endoxifen levels (5.97 ng/mL). Compared to the low-cholesterol group, the high-cholesterol group had a lower 4-hydroxytamoxifen or endoxifen level in T/T carriers. In T/T carriers, the high-cholesterol group had an increased risk of an ineffective endoxifen level. Metastasis, hot flash/flushing, and high alanine transaminase did not relate to plasma 4-hydroxytamoxifen or endoxifen levels. Results indicate that C100T and high serum cholesterol are risk factors of ineffective endoxifen levels in Taiwanese breast cancer patients. These findings warrant further studies of a large hypercholesterolemic population to examine the outcome of increased doses of tamoxifen.

In 2009, a swine-origin influenza A virus - A(H1N1)pdm09 - emerged and has became a pandemic strain circulating worldwide. The hemagglutinin (HA) of influenza virus is a potential target for the development of anti-viral therapeutic agents. Here, we generated mAbs by immunization of baculovirus-insect expressing trimeric recombinant HA of the A(H1N1)pdm09 strain. Results indicated that the mAbs recognized two novel neutralizing and protective epitopes-"STAS" and "FRSK" which located near Cb and Ca1 antigenic regions respectively and were conserved in almost 2009-2016 influenza H1N1 stains. The mAb 12E11 demonstrated higher protective efficacy than mAb 8B10 in mice challenge assay. Both mAb pretreatments significantly reduced virus titers and pro-inflammatory cytokines in mice lung postinfection (p 0.01), and showed prophylactic and therapeutic efficacies even 48 h postinfection (p 0.05). Combination therapy using the mAbs with oseltamivir pre- and post-treatment showed synergistic therapeutic effect in mice model (p 0.01). Further investigation for clinical application in humans is warranted.

// Sheng-Fan Wang 1, 2 , Meng-Shian Chen 1 , Yueh-Ching Chou 1, 2, 3 , Yune-Fang Ueng 1, 4, 5 , Pen-Hui Yin 6 , Tien-Shun Yeh 7 , Hsin-Chen Lee 1 1 Department and Institute of Pharmacology, School of Medicine, National Yang-Ming University, Taipei, Taiwan 2 Department of Pharmacy, Taipei Veterans General Hospital, Taipei, Taiwan 3 School of Pharmacy, Taipei Medical University, Taipei, Taiwan 4 National Research Institute of Chinese Medicine, Ministry of Health and Welfare, Taipei, Taiwan 5 Institute of Medical Sciences, Taipei Medical University, Taipei, Taiwan 6 Department of Medical Research, Taipei Veterans General Hospital, Taipei, Taiwan 7 Institute of Anatomy and Cell Biology, School of Medicine, National Yang-Ming University, Taipei, Taiwan Correspondence to: Hsin-Chen Lee, email: hclee2@ym.edu.tw Keywords: gastric cancer, mitochondrial dysfunction, cisplatin resistance, xCT, retrograde signaling Received: June 14, 2016 Accepted: September 21, 2016 Published: September 30, 2016 ABSTRACT Mitochondrial DNA mutations and defects in mitochondrial enzymes have been identified in gastric cancers, and they might contribute to cancer progression. In previous studies, mitochondrial dysfunction was induced by oligomycin-enhanced chemoresistance to cisplatin. Herein, we dissected the regulatory mechanism for mitochondrial dysfunction-enhanced cisplatin resistance in human gastric cancer cells. Repeated cisplatin treatment-induced cisplatin-resistant cells exhibited high SLC7A11 (xCT) expression, and xCT inhibitors (sulfasalazine or erastin), xCT siRNA, or a GSH synthesis inhibitor (buthionine sulphoximine, BSO) could sensitize these cells to cisplatin. Clinically, the high expression of xCT was associated with a poorer prognosis for gastric cancer patients under adjuvant chemotherapy. Moreover, we found that mitochondrial dysfunction enhanced cisplatin resistance and up-regulated xCT expression, as well as intracellular glutathione (GSH). The xCT inhibitors, siRNA against xCT or BSO decreased mitochondrial dysfunction-enhanced cisplatin resistance. We further demonstrated that the upregulation of the eIF2α-ATF4 pathway contributed to mitochondrial dysfunction-induced xCT expression, and activated eIF2α kinase GCN2, but not PERK, stimulated the eIF2α-ATF4-xCT pathway in response to mitochondrial dysfunction-increased reactive oxygen species (ROS) levels. In conclusion, our results suggested that the ROS-activated GCN2-eIF2α-ATF4-xCT pathway might contribute to mitochondrial dysfunction-enhanced cisplatin resistance and could be a potential target for gastric cancer therapy.

The radiation output characteristics of the transmission-target X-ray tube are different from those of the traditional reflection-target X-ray tube. The aims of this study were to compare the differences of output dose and spectrum between these two X-ray tubes under the same conditions. The biomedical applications of the transmission-target X-ray in liver cancer cells were also evaluated. For these two systems, the dose output and the mAs appeared to have good linear relations; the dose output and kVp variations also had positive relations. However, under the same parameters, the dose output of transmission-target X-ray system was 2.64–3.21 times higher than the reflection-target system, implying that the transmission-target system had a higher X-ray production rate. The K characteristic radiations reach 22.96% and 8.91% of the spectrum in transmission-target and reflection-target, respectively. The spectrum measurements showed that the transmission-target system had more obvious output of K characteristic radiation. The 1 Gy of transmission-target can induce 16%–23% of cytotoxicity in liver cancer cells. Concerning the synergic effects of transmission-target combined with rose bengal, the data showed that 1 Gy of transmission-target exposure augment the 24%–28% of cytotoxicity at low dose of rose bengal treated condition.

Background: Gastric cancer is a common health issue. Deregulated cellular energetics is regarded as a cancer hallmark and mitochondrial dysfunction might contribute to cancer progression. Tid1, a mitochondrial co-chaperone, may play a role as a tumor suppressor in various cancers, but the role of Tid1 in gastric cancers remains under investigated. Methods: The clinical TCGA online database and immunohistochemical staining for Tid1 expression in tumor samples of gastric cancer patients were analyzed. Tid1 knockdown by siRNA was applied to investigate the role of Tid1 in gastric cancer cells. Results: Low Tid1 protein-expressing gastric cancer patients had a poorer prognosis and higher lymph node invasion than high Tid1-expressing patients. Knockdown of Tid1 did not increase cell proliferation, colony/tumor sphere formation, or chemotherapy resistance in gastric cancer cells. However, Tid1 knockdown increased cell migration and invasion. Moreover, Tid1 knockdown reduced the mtDNA copy number of gastric cancer cells. In addition, the Tid1-galectin-7-MMP-9 axis might be associated with Tid1 knockdown&ndash, induced cell migration and invasion of gastric cancer cells. Conclusions: Tid1 is required for mtDNA maintenance and regulates migration and invasion of gastric cancer cells. Tid1 deletion may be a poor prognostic factor in gastric cancers and could be further investigated for development of gastric cancer treatments.

COVID-19 has recently become a pandemic affecting many countries worldwide. This study aims to evaluate the current status of COVID-19 in Taiwan and analyze the source of infection.National data regarding SARS-CoV-2 infection were obtained from Taiwan. CDC at the end of April 2020. These data were subjected to analysis of the current status and correlation between indigenous and imported COVID-19 cases. A phylogenetic tree was created to analyze the phylogeny of Taiwanese SARS-CoV-2 isolates.The first case of SARS-CoV-2 infection in Taiwan was detected on January 21, 2020. Epidemiological data indicate that by April 30, there were a total of 429 COVID-19 confirmed cases with the death rate of 1.3%. Most cases were identified as imported (79.9%; 343/429), with the majority originating from the United States of America (22.1%) and the United Kingdom (17.6%). Results from phylogenetic tree analyses indicate that the Taiwanese SARS-CoV-2 isolates were clustered with the SARS-CoV-2 isolates from other countries (bootstrap value 98%) and sub-clustered with bat SARS-like coronaviruses (bootstrap value 99%).This study suggests that the importation of SARS-CoV-2 infection was the primary risk-factor resulting in the COVID-19 epidemic in Taiwan.

HIV-1 CRF07_BC is a recombinant virus with amino acid (a.a.) deletions in p6Gag, which are overlapped with the Alix-binding domain. Galectin-3 (Gal3), a &beta, galactose binding lectin, has been reported to interact with Alix and regulate HIV-1 subtype B budding. This study aims to evaluate the role of Gal3 in HIV-1 CRF07_BC infection and the potential effect of a.a. deletions on Gal3-mediated regulation. A total of 38 HIV-1+ injecting drug users (IDUs) were enrolled in the study. Viral characterization and correlation of Gal3 were validated. CRF07_BC containing 7 a.a. deletions and wild-type in the p6Gag (CRF07_BC-7d and -wt) were isolated and infectious clones were generated. Viral growth kinetic and budding assays using Jurkat-CCR5/Jurkat-CCR5-Gal3 cells infected with CRF07_BC were performed. Results indicate that 69.4% (25/38) of the recruited patients were identified as CRF07_BC, and CRF07_BC-7d was predominant. Slow disease progression and significantly higher plasma Gal3 were noted in CRF07_BC patients (p &lt, 0.01). Results revealed that CRF07_BC infection resulted in Gal3 expression, which was induced by Tat. Growth dynamic and budding assays indicated that Gal3 expression in Jurkat-CCR5 cells significantly enhanced CRF07_BC-wt replication and budding (p &lt, 0.05), while the promoting effect was ameliorated in CRF07_BC-7d. Co-immunoprecipitation found that deletions in the p6Gag reduced Gal-3-mediated enhancement of the Alix&ndash, Gag interaction.

The integrated stress response (ISR) pathway is essential for adaption of various stresses and is related to mitochondrion-to-nucleus communication. Mitochondrial dysfunction-induced reactive oxygen species (ROS) was demonstrated to activate general control nonderepressible 2 (GCN2)–eukaryotic translation initiation factor 2α (eIF2α)–activating transcription factor-4 (ATF4) pathway-mediated cisplatin resistance of human gastric cancer cells. However, whether or how ISR activation per se could enhance chemoresistance remains unclear. In this study, we used eIF2α phosphatase inhibitor salubrinal to activate the ISR pathway and found that salubrinal reduced susceptibility to cisplatin. Moreover, salubrinal up-regulated ATF4-modulated gene expression, and knockdown of ATF4 attenuated salubrinal-induced drug resistance, suggesting that ATF4-modulated genes contribute to the process. The ATF4-modulated genes, xCT (a cystine/glutamate anti-transporter), tribbles-related protein 3 (TRB3), heme oxygenase 1 (HO-1), and phosphoenolpyruvate carboxykinase 2 (PCK2), were associated with a poorer prognosis for gastric cancer patients. By silencing individual genes, we found that xCT, but not TRB3, HO-1, or PCK2, is responsible for salubrinal-induced cisplatin resistance. In addition, salubrinal increased intracellular glutathione (GSH) and decreased cisplatin-induced lipid peroxidation. Salubrinal-induced cisplatin resistance was attenuated by inhibition of xCT and GSH biosynthesis. In conclusion, our results suggest that ISR activation by salubrinal up-regulates ATF4-modulated gene expression, increases GSH synthesis, and decreases cisplatin-induced oxidative damage, which contribute to cisplatin resistance in gastric cancer cells.

Non-alcoholic fatty liver disease (NAFLD) has become the most common liver disease in the recent decades in both developed and developing countries, and is predicted to be the major etiology for liver transplantation in the next decade. Thus, pharmacological strategies to treat NAFLD are urgently needed. Natural products are considered an excellent source for drug discovery. By utilizing an image-based high-throughput screening with a library containing 3000 Taiwanese indigenous plant extracts, we discovered that the extract of Syzygium simile leaves (SSLE) has an anti-lipid droplet (LD) accumulation effect in hepatic cell lines. Analyses of the expression profile of genes involved in lipid metabolism revealed that SSLE suppressed the mRNA expression of CD36, fatty acid translocase. In agreement with this observation, we showed that SSLE inhibited CD36 protein expression and fatty acid uptake and has only limited effects on pre-formed LDs. Moreover, SSLE reduced LD accumulation and CD36 expression in enterocyte and macrophage cell lines. In conclusion, our findings suggest that SSLE could serve as a potential source for the discovery of novel therapeutic modalities for NAFLD and that the suppression of CD36 expression and fatty acid uptake could contribute to the lipid-lowering effect of SSLE.

In 2013 a new reassortant avian influenza A H7N9 virus emerged in China, causing human infection with high mortality. An accurate and timely diagnosis is crucial for controlling the outbreaks of the disease. We therefore propose a simple strategy for rapidly and sensitively detecting the H7N9 virus using an intensity-modulated surface plasmon resonance (IM-SPR) biosensor integrated with a new generated monoclonal antibody. The novel antibody exhibits significant specificity to recognize H7N9 virus compared with other clinical human influenza isolates (p0.01). Experimentally, the detection limit of the proposed approach for H7N9 virus detection is estimated to be 144 copies/mL, which is a 20-fold increase in sensitivity compared with homemade target-captured ELISA using the identical antibody. For the measurement of mimic clinical specimens containing the H7N9 virus mixed with nasal mucosa from flu-like syndrome patients, the detection limit is calculated to be 402 copies/mL, which is better than conventional influenza detection assays; quantitative reverse transcription polymerase chain reaction (qRT-PCR) and rapid influenza diagnostic test (RIDT). Most importantly, the assay time took less than 10 min. Combined, the results of this study indicate that the proposed simple strategy demonstrates high sensitivity and time-saving in H7N9 virus detection. By incorporating a high specific recognizer, the proposed technique has the potential to be used in applications and development of other emerging or re-emerging microbe detection platforms.

Highly pathogenic avian influenza A H5N1 virus causes pneumonia and acute respiratory distress syndrome in humans. Virus-induced excessive inflammatory response contributes to severe disease and high mortality rates. Galectin-3, a β-galactoside-binding protein widely distributed in immune and epithelial cells, regulates various immune functions and modulates microbial infections. Here, we describe galectin-3 up-regulation in mouse lung tissue after challenges with the H5N1 influenza virus. We investigated the effects of endogenous galectin-3 on H5N1 infection and found that survival of galectin-3 knockout (Gal-3KO) mice was comparable with wild-type (WT) mice after infections. Compared with infected WT mice, infected Gal-3KO mice exhibited less inflammation in the lungs and reduced IL-1β levels in bronchoalveolar lavage fluid. In addition, the bone marrow–derived macrophages (BMMs) from Gal-3KO mice exhibited reduced oligomerization of apoptosis-associated speck-like proteins containing caspase-associated recruitment domains and secreted less IL-1β compared with BMMs from WT mice. However, similar levels of the inflammasome component of nucleotide oligomerization domain–like receptor protein 3 (NLRP3) were observed in two genotypes of BMMs. Co-immunoprecipitation data indicated galectin-3 and NLRP3 interaction in BMMs infected with H5N1. An association was also observed between galectin-3 and NLRP3/apoptosis-associated speck-like proteins containing caspase-associated recruitment domain complex. Combined, our results suggest that endogenous galectin-3 enhances the effects of H5N1 infection by promoting host inflammatory responses and regulating IL-1β production by macrophages via interaction with NLRP3.

Cancer cells exhibit an abnormal amino acid metabolism and a dependence on specific amino acids, which might provide potential targets for treating cancer patients. In this study, we demonstrated that human triple negative breast cancer (TNBC) cells were highly susceptible to cystine starvation. We found that necrostatin-1 (Nec-1, a RIP1 inhibitor), necrosulfonamide (an MLKL inhibitor), deferoxamine (an ion chelator), ferrostatin-1 (a ferroptosis inhibitor) and RIP1 knockdown can prevent cystine-starvation-induced cell death, suggesting that cystine starvation induces necroptosis and ferroptosis in TNBC cells. Moreover, cystine starvation induced mitochondrial fragmentation, dysfunction, and ROS production. A mitochondrial ROS scavenger, Necrox-5, can prevent cystine-starvation-induced cell death. In addition, cystine starvation was found to activate GCN2, but not PERK, to increase the phosphorylation of eIF2α at serine 51, the protein expression of ATF4, and the expression of ATF4 target genes such as CHAC1, which might be downstream of the RIP1/RIP3-MLKL pathway and contribute to cystine-starvation-induced cell death. Knockdown of CHAC1 rescued the cystine-starvation-induced reduction in glutathione (GSH) levels and cell death. Furthermore, N-acetyl-cysteine (NAC), Trolox, and Nec-1 significantly prevented the cystine-starvation-induced increase in intracellular ROS levels, mitochondrial fragmentation and cell death. In summary, these results suggest that CHAC1 degradation of GSH enhances cystine-starvation-induced necroptosis and ferroptosis through the activated GCN2-eIF2α-ATF4 pathway in TNBC cells. Our findings improve our understanding of the mechanism underlying cystine-starvation-induced TNBC cell death.