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This paper proposes a design method for a robust fractional-order PID (FOPID) controller for time-delay systems. A new Bode's ideal transfer function is introduced to tolerance the time-delay in loop. Robust stability is analyzed for the Bode's model in terms of gain and phase margins to help the parameter tuning. To simplify FOPID design from solving nonlinear equations, five unknown parameters are reduced to one in the Bode shaping by data fitting between a parametric model and the real plant. Then, the problem is simply solved by one-dimensional searching. Furthermore, the proposed FOPID controller design is extended to multi-input and multi-output (MIMO) systems by using disturbance observer (DOB). Finally, simulation results are presented to show the effectiveness of the proposed method.

The evolution of SARS‐CoV‐2 paired with immune imprinting by prototype messenger RNA (mRNA) vaccine has challenged the current vaccination efficacy against newly emerged Omicron subvariants. In our study, we investigated a cohort of macaques infected by SIV and vaccinated with two doses of bivalent Pfizer mRNA vaccine containing wildtype and BA.5 spikes. Using a pseudotyped lentivirus neutralization assay, we determined neutralizing antibody (nAb) titers against new XBB variants, i.e., XBB.1.5, XBB.1.16, and XBB.2.3, alongside D614G and BA.4/5. We found that compared to humans vaccinated with three doses of monovalent mRNA vaccine plus a bivalent booster, the monkeys vaccinated with two doses of bivalent mRNA vaccines exhibited relatively increased titers against XBB subvariants. Of note, SIV‐positive dam macaques had reduced nAb titers relative to SIV‐negative dams. Additionally, SIV positive dams that received antiretroviral therapy had lower nAb titers than untreated dams. Our study underscores the importance of reformulating the COVID‐19 vaccine to better protect against newly emerged XBB subvariants as well as the need for further investigation of vaccine efficacy in individuals living with HIV‐1. [ABSTRACT FROM AUTHOR]

Intratumoral immune status influences tumor therapeutic response, but it remains largely unclear how the status determines therapies for patients with intrahepatic cholangiocarcinoma. Here, we examine the single-cell transcriptional and TCR profiles of 18 tumor tissues pre- and post- therapy of gemcitabine plus oxaliplatin, in combination with lenvatinib and anti-PD1 antibody for intrahepatic cholangiocarcinoma. We find that high CD8 GZMB+ and CD8 proliferating proportions and a low Macro CD5L+ proportion predict good response to the therapy. In patients with a poor response, the CD8 GZMB+ and CD8 proliferating proportions are increased, but the CD8 GZMK+ proportion is decreased after the therapy. Transition of CD8 proliferating and CD8 GZMB+ to CD8 GZMK+ facilitates good response to the therapy, while Macro CD5L+–CD8 GZMB+ crosstalk impairs the response by increasing CTLA4 in CD8 GZMB+. Anti-CTLA4 antibody reverses resistance of the therapy in intrahepatic cholangiocarcinoma. Our data provide a resource for predicting response of the combination therapy and highlight the importance of CD8+T-cell status conversion and exhaustion induced by Macro CD5L+ in influencing the response, suggesting future avenues for cancer treatment optimization. The role of the tumor microenvironment in immunotherapy response in intrahepatic cholangiocarcinoma remains unclear. Here, single cell RNA and TCR sequencing of samples before and after immunotherapy highlights the role of CD8 T-cell status conversion and exhaustion induced by Macro CD5L+ in treatment response. [ABSTRACT FROM AUTHOR]

Purpose: We aimed to study the association between adjusted mtDNA levels in human trophectoderm biopsy samples and the developmental potential of euploid and mosaic blastocysts. Methods: We analyzed relative mtDNA levels in 2,814 blastocysts obtained from 576 couples undergoing preimplantation genetic testing for aneuploidy from June 2018 to June 2021. All patients underwent in vitro fertilization in a single clinic; the study was blinded—mtDNA content was unknown at the time of single embryo transfer. The fate of the euploid or mosaic embryos transferred was compared with mtDNA levels. Results: Euploid embryos had lower mtDNA than aneuploid and mosaic embryos. Embryos biopsied on Day 5 had higher mtDNA than those biopsied on Day 6. No difference was detected in mtDNA scores between embryos derived from oocytes of different maternal ages. Linear mixed model suggested that blastulation rate was associated with mtDNA score. Moreover, the specific next-generation sequencing platform used have a significant effect on the observed mtDNA content. Euploid embryos with higher mtDNA content presented significantly higher miscarriage rates and lower live birth rates, while no significant difference was observed in the mosaic cohort. Conclusion: Our results will aid in improving methods for analyzing the association between mtDNA level and blastocyst viability. [ABSTRACT FROM AUTHOR]

Research reveals that heme group is bound tightly at the active site of rabbit cytochrome P450-4B1 (CYP4B1) and base treatment of rabbit CYP4A human CYP4F subfamilies of heme-containing monooxygenases release a polar heme derivative. The general structural feature of mammalian CYP4 proteins may contain a covalently linked heme.

Clustered regularly interspaced short palindromic repeats (CRISPR) system provides adaptive immunity against plasmids and phages in prokaryotes. This system inspires the development of a powerful genome engineering tool, the CRISPR/CRISPR-associated nuclease 9 (CRISPR/Cas9) genome editing system. Due to its high efficiency and precision, the CRISPR/Cas9 technique has been employed to explore the functions of cancer-related genes, establish tumor-bearing animal models and probe drug targets, vastly increasing our understanding of cancer genomics. Here, we review current status of CRISPR/Cas9 gene editing technology in oncological research. We first explain the basic principles of CRISPR/Cas9 gene editing and introduce several new CRISPR-based gene editing modes. We next detail the rapid progress of CRISPR screening in revealing tumorigenesis, metastasis, and drug resistance mechanisms. In addition, we introduce CRISPR/Cas9 system delivery vectors and finally demonstrate the potential of CRISPR/Cas9 engineering to enhance the effect of adoptive T cell therapy (ACT) and reduce adverse reactions. [ABSTRACT FROM AUTHOR]

Potentiating interferon responses: The host restriction factor SERINC5 is found in the plasma membrane and is thought to inhibit HIV-1 infection through its incorporation into virions. Zeng et al. showed that upon viral infection of cells, SERINC5 also localized to mitochondria, where it interacted with the adaptor protein MAVS and promoted its oligomerization. Signaling downstream of MAVS led to activation of transcriptional regulators of the IRF and NF-κB families and the expression of genes encoding type I interferons (IFNs) and proinflammatory cytokines. KD of SERINC5 enhanced the replication of various viruses, suggesting that the potentiation of IFN and inflammatory cytokine signaling represents an additional antiviral response mediated by SERINC5. The SERINC (serine incorporator) proteins are host restriction factors that inhibit infection by HIV through their incorporation into virions. Here, we found that SERINC3 and SERINC5 exhibited additional antiviral activities by enhancing the expression of genes encoding type I interferons (IFNs) and nuclear factor κB (NF-κB) signaling. SERINC5 interacted with the outer mitochondrial membrane protein MAVS (mitochondrial antiviral signaling) and the E3 ubiquitin ligase and adaptor protein TRAF6, resulting in MAVS aggregation and polyubiquitylation of TRAF6. Knockdown of SERINC5 in target cells increased single-round HIV-1 infectivity, as well as infection by recombinant vesicular stomatitis virus (rVSV) bearing VSV-G or Ebola virus (EBOV) glycoproteins. Infection by an endemic Asian strain of Zika virus (ZIKV), FSS13025, was also enhanced by SERINC5 knockdown, suggesting that SERINC5 has direct antiviral activities in host cells in addition to the indirect inhibition mediated by its incorporation into virions. Further experiments suggested that the antiviral activity of SERINC5 was type I IFN–dependent. Together, these results highlight a previously uncharacterized function of SERINC proteins in promoting NF-κB inflammatory signaling and type I IFN production, thus contributing to its antiviral activities. [ABSTRACT FROM AUTHOR]

Although long noncoding RNAs (lncRNAs) have significant tissue specificity, their expression and variability in single cells remain unclear. Here, we developed ColorCells (http://rna.sysu.edu.cn/colorcells/), a resource for comparative analysis of lncRNAs expression, classification and functions in single-cell RNA-Seq data. ColorCells was applied to 167 913 publicly available scRNA-Seq datasets from six species, and identified a batch of cell-specific lncRNAs. These lncRNAs show surprising levels of expression variability between different cell clusters, and has the comparable cell classification ability as known marker genes. Cell-specific lncRNAs have been identified and further validated by in vitro experiments. We found that lncRNAs are typically co-expressed with the mRNAs in the same cell cluster, which can be used to uncover lncRNAs' functions. Our study emphasizes the need to uncover lncRNAs in all cell types and shows the power of lncRNAs as novel marker genes at single cell resolution. [ABSTRACT FROM AUTHOR]

Research has been conducted on CYP4B1. The authors report their investigation of the heme ester link site in CYP4B1, and their study of the functional consequences of the active site mutations.

The evolution of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to challenge the efficacy of vaccination efforts against coronavirus disease 2019 (COVID-19). The Omicron XBB lineage of SARS-CoV-2 has presented dramatic evasion of neutralizing antibodies stimulated by mRNA vaccination and COVID-19 convalescence. XBB.1.16, characterized by two mutations relative to the dominating variant XBB.1.5, i.e., E180V and K478R, has been on the rise globally. In this study, we compare the immune escape of XBB.1.16 with XBB.1.5, alongside ancestral variants D614G, BA.2, and BA.4/5. We demonstrate that XBB.1.16 is strongly immune evasive, with extent comparable to XBB.1.5 in bivalent-vaccinated healthcare worker sera, 3-dose-vaccinated healthcare worker sera, and BA.4/5-wave convalescent sera. Interestingly, the XBB.1.16 spike is less fusogenic than that of XBB.1.5, and this phenotype requires both E180V and K478R mutations to manifest. Overall, our findings emphasize the importance of the continued surveillance of variants and the need for updated mRNA vaccine formulations. [Display omitted] • XBB.1.16 exhibits high extents of immune escape comparable to XBB.1.5 • XBB.1.16 escapes neutralizing antibodies in bivalent- and 3-dose-vaccinated sera • XBB.1.16 spike is less fusogenic than XBB.1.5 due to the E180V and K478R mutations • Higher infectivity of XBB.1.16 in 293T-ACE2 cells is driven by the K478R mutation SARS-CoV-2 continues to exhibit increasing immune escape. Here, Faraone et al. demonstrate that XBB.1.16 escapes antibodies in bivalent-vaccinated, 3-dose-vaccinated, and BA.4/5-wave convalescent sera to a similar extent compared with XBB.1.5. They also show that the XBB.1.16 spike is less fusogenic than XBB.1.5 but exhibits enhanced infectivity. [ABSTRACT FROM AUTHOR]

Omicron subvariants continuingly challenge current vaccination strategies. Here, we demonstrate nearly complete escape of the XBB.1.5, CH.1.1, and CA.3.1 variants from neutralizing antibodies stimulated by three doses of mRNA vaccine or by BA.4/5 wave infection, but neutralization is rescued by a BA.5-containing bivalent booster. CH.1.1 and CA.3.1 show strong immune escape from monoclonal antibody S309. Additionally, XBB.1.5, CH.1.1, and CA.3.1 spike proteins exhibit increased fusogenicity and enhanced processing compared with BA.2. Homology modeling reveals the key roles of G252V and F486P in the neutralization resistance of XBB.1.5, with F486P also enhancing receptor binding. Further, K444T/M and L452R in CH.1.1 and CA.3.1 likely drive escape from class II neutralizing antibodies, whereas R346T and G339H mutations could confer the strong neutralization resistance of these two subvariants to S309-like antibodies. Overall, our results support the need for administration of the bivalent mRNA vaccine and continued surveillance of Omicron subvariants. [Display omitted] • Bivalent booster induces 2- to 8-fold higher nAb titer than monovalent against XBB and XBB.1.5 • CH.1.1 and CA.3.1 exhibit nearly complete escape of neutralization from bivalent booster • XBB.1.5, CH.1.1, and CA.3.1 show increased fusogenicity compared with BA.2 • Homology modeling shows impacts of F486P mutation present in XBB.1.5 on ACE2 binding Qu et al. show that bivalent booster recipients, compared with monovalent recipients, exhibit higher nAb titers against Omicron subvariants XBB, XBB.1, and XBB.1.5. The CH.1.1 and CA.3.1 variants show more substantial neutralization escape than the XBB variants. Further, structural modeling reveals that the F486P mutation in XBB.1.5 enhances ACE2 binding. [ABSTRACT FROM AUTHOR]

The continued evolution of SARS-CoV-2 has led to the emergence of several new Omicron subvariants, including BQ.1, BQ.1.1, BA.4.6, BF.7, and BA.2.75.2. Here, we examine the neutralization resistance of these subvariants against sera from 3-dose vaccinated healthcare workers, hospitalized BA.1-wave patients, and BA.4/5-wave patients. We found enhanced neutralization resistance in all new subvariants, especially in the BQ.1 and BQ.1.1 subvariants driven by N460K and K444T mutations, as well as the BA.2.75.2 subvariant driven largely by its F486S mutation. All Omicron subvariants maintained their weakened infectivity in Calu-3 cells, with the F486S mutation driving further diminished titer for the BA.2.75.2 subvariant. Molecular modeling revealed the mechanisms of antibody-mediated immune evasion by R346T, K444T, F486S, and D1199N mutations. Altogether, these findings shed light on the evolution of newly emerging SARS-CoV-2 Omicron subvariants. [Display omitted] • Enhanced neutralization resistance of BQ.1 and BQ.1.1 is driven by N460K and K444T • Enhanced neutralization resistance of BA.2.75.2 is driven by F486S • R346T and K444T contribute to evasion of class III antibody recognition • Modeling reveals that F486S reduces binding for both ACE2 and class I and II antibodies Numerous Omicron subvariants have emerged following BA.4/5 and BA.2.75 subvariants. Qu and colleagues investigate the neutralizing antibody resistance of these subvariants and their ancestral variants. BQ.1, BQ.1.1, BA.4.6, BF.7, and BA.2.75.2 exhibit enhanced neutralizing antibody escape, with BQ.1/BQ.1.1 and BA.2.75.2 driven by N460K/K444T and F486S mutations, respectively. [ABSTRACT FROM AUTHOR]

Interferon-induced transmembrane (IFITM) proteins are potent antiviral factors shown to restrict the infection of many enveloped viruses, including HIV. Here we report cloning and characterization of a panel of nonhuman primate IFITMs. We show that, similar to human IFITM, nonhuman primate IFITM proteins inhibit HIV and other primate lentiviruses. While some nonhuman primate IFITM proteins are more potent than human counterparts to inhibit HIV-1, they are generally not effective against HIV-2 similar to that of human IFITMs. Notably, depending on SIV strains and also IFITM species tested, nonhuman primate IFITM proteins exhibit distinct activities against SIVs; no correlation was found to support the notion that IFITM proteins are most active in non-natural primate hosts. Consistent with our recent findings for human IFITMs, nonhuman primate IFITM proteins interact with HIV-1 Env and strongly act in viral producer cells to impair viral infectivity and block cell-to-cell transmission. Accordingly, knockdown of primate IFITM3 increases HIV-1 replication in nohuman primate cells. Interestingly, analysis of DNA sequences of human and nonhuman primate IFITMs suggest that IFITM proteins have been undergoing purifying selection, rather than positive selection typical for cellular restriction factors. Overall, our study reveals some new and unexpected features of IFITMs in restricting primate lentiviruses, which enhances our understanding of virus-host interaction and AIDS pathogenesis. [ABSTRACT FROM AUTHOR]

Ebola virus (EBOV) is a highly pathogenic filovirus that causes hemorrhagic fever in humans and animals. Currently, how EBOV fuses its envelope membrane within an endosomal membrane to cause infection is poorly understood. We successfully measure cell-cell fusion mediated by the EBOV fusion protein, GP, assayed by the transfer of both cytoplasmic and membrane dyes. A small molecule fusion inhibitor, a neutralizing antibody, as well as mutations in EBOV GP known to reduce viral infection, all greatly reduce fusion. By monitoring redistribution of small aqueous dyes between cells and by electrical capacitance measurements, we discovered that EBOV GP-mediated fusion pores do not readily enlarge—a marked difference from the behavior of other viral fusion proteins. EBOV GP must be cleaved by late endosome-resident cathepsins B or L in order to become fusion-competent. Cleavage of cell surface-expressed GP appears to occur in endosomes, as evidenced by the fusion block imposed by cathepsin inhibitors, agents that raise endosomal pH, or an inhibitor of anterograde trafficking. Treating effector cells with a recombinant soluble cathepsin B or thermolysin, which cleaves GP into an active form, increases the extent of fusion, suggesting that a fraction of surface-expressed GP is not cleaved. Whereas the rate of fusion is increased by a brief exposure to acidic pH, fusion does occur at neutral pH. Importantly, the extent of fusion is independent of external pH in experiments in which cathepsin activity is blocked and EBOV GP is cleaved by thermolysin. These results imply that low pH promotes fusion through the well-known pH-dependent activity of cathepsins; fusion induced by cleaved EBOV GP is a process that is fundamentally independent of pH. The cell-cell fusion system has revealed some previously unappreciated features of EBOV entry, which could not be readily elucidated in the context of endosomal entry. [ABSTRACT FROM AUTHOR]

The newly emerged BA.2.75 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variant contains 9 additional mutations in its spike (S) protein compared to the ancestral BA.2 variant. Here, we examine the neutralizing antibody escape of BA.2.75 in mRNA-vaccinated and BA.1-infected individuals, as well as the molecular basis underlying functional changes in S. Notably, BA.2.75 exhibits enhanced neutralization resistance over BA.2 but less than the BA.4/5 variant. The G446S and N460K mutations of BA.2.75 are primarily responsible for its enhanced resistance to neutralizing antibodies. The R493Q mutation, a reversion to the prototype sequence, reduces BA.2.75 neutralization resistance. The impact of these mutations is consistent with their locations in common neutralizing antibody epitopes. Further, BA.2.75 shows enhanced cell-cell fusion over BA.2, driven largely by the N460K mutation, which enhances S processing. Structural modeling reveals enhanced receptor contacts introduced by N460K, suggesting a mechanism of potentiated receptor utilization and syncytia formation. • BA.2.75 shows enhanced neutralization resistance and fusion over BA.2 but not BA.4/5 • G446S, and to a lesser extent N460K, determines enhanced neutralization resistance • N460K drives enhanced spike processing and cell-cell fusion of BA.2.75 • N460K potentiates ACE2 interactions likely by forming a salt bridge and hydrogen bond Newly emerged Omicron subvariants reignite concerns over escape from existing immunity. Qu and colleagues compare the immunity resistance and fusogenicity of BA.2.75 with prior variants. BA.2.75 exhibits stronger neutralization resistance than BA.2 but weaker than BA.4/5, as well as enhanced fusogenicity, which are largely driven by G446S and N460K, respectively. [ABSTRACT FROM AUTHOR]

Summary The interferon-induced transmembrane (IFITM) proteins have been recently shown to restrict HIV-1 and other viruses. Here, we provide evidence that IFITM proteins, particularly IFITM2 and IFITM3, specifically antagonize the HIV-1 envelope glycoprotein (Env), thereby inhibiting viral infection. IFITM proteins interact with HIV-1 Env in viral producer cells, leading to impaired Env processing and virion incorporation. Notably, the level of IFITM incorporation into HIV-1 virions does not strictly correlate with the extent of inhibition. Prolonged passage of HIV-1 in IFITM-expressing T lymphocytes leads to emergence of Env mutants that overcome IFITM restriction. The ability of IFITMs to inhibit cell-to-cell infection can be extended to HIV-1 primary isolates, HIV-2 and SIVs; however, the extent of inhibition appears to be virus-strain dependent. Overall, our study uncovers a mechanism by which IFITM proteins specifically antagonize HIV-1 Env to restrict HIV-1 infection and provides insight into the specialized role of IFITMs in HIV infection. [ABSTRACT FROM AUTHOR]

Recent reports of SARS-CoV-2 Omicron variant sub-lineages, BA.1, BA.1.1, and BA.2, have reignited concern over potential escape from vaccine- and infection-induced immunity. We examine the sensitivity of these sub-lineages and other major variants to neutralizing antibodies from mRNA-vaccinated and boosted individuals, as well as recovered COVID-19 patients, including those infected with Omicron. We find that all Omicron sub-lineages, especially BA.1 and BA.1.1, exhibit substantial immune escape that is largely overcome by mRNA vaccine booster doses. While Omicron BA.1.1 escapes almost completely from neutralization by early-pandemic COVID-19 patient sera and to a lesser extent from sera of Delta-infected patients, BA.1.1 is sensitive to Omicron-infected patient sera. Critically, all Omicron sub-lineages, including BA.2, are comparably neutralized by Omicron patient sera. These results highlight the importance of booster vaccine doses for protection against all Omicron variants and provide insight into the immunity from natural infection against Omicron sub-lineages. [Display omitted] • BA.1.1, BA.1, and BA.2 escape neutralization by two-dose mRNA vaccinee sera • Booster vaccination recovers Omicron immunity to levels comparable to Delta • Sera from Omicron, but not D614G or Delta, COVID-19 patients neutralize Omicron • The Omicron "EPE214" insertion does not dictate neutralization resistance The emerging SARS-CoV-2 Omicron variants may threaten existing COVID-19 immunity. Evans and colleagues examine immunity against the BA.1.1 and BA.2 variants, as well as prior SARS-CoV-2 variants, in two- and three-dose vaccinated individuals and recovered COVID-19 patients. Booster vaccination, but not two-dose vaccinee or non-Omicron-infected patient sera, neutralizes Omicron. [ABSTRACT FROM AUTHOR]

Members of the interferon-induced transmembrane ( IFITM) protein family inhibit the entry of a wide range of viruses. Viruses often exploit the endocytosis pathways to invade host cells and escape from the endocytic vesicles often in response to low pH. Localization to these endocytic vesicles is essential for IFITM3 to interfere with the cytosolic entry of pH-dependent viruses. However, the nature of the sorting signal that targets IFITM3 to these vesicles is poorly defined. In this study, we report that IFITM3 possesses a YxxΦ sorting motif, i.e. 20- YEML-23, that enables IFITM3 to undergo endocytosis through binding to the μ2 subunit of the AP-2 complex. IFITM3 accumulates at the plasma membrane as a result of either mutating 20- YEML-23, depleting the μ2 subunit or overexpressing μ2 mutants. Importantly, blocking endocytosis of IFITM3 abrogates its ability to inhibit pH-dependent viruses. We have therefore identified a critical sorting signal, namely 20- YEML-23, that controls both the endocytic trafficking and the antiviral action of IFITM3. This finding also reveals that as an endocytic protein, IFITM3 first arrives at the plasma membrane before it is endocytosed and further traffics to the late endosomes where it acts to impede virus entry. [ABSTRACT FROM AUTHOR]

Abstract: Jaagsiekte sheep retrovirus (JSRV) and enzootic nasal tumor virus (ENTV) are two closely related oncogenic retroviruses that share the same cellular receptor yet exhibit distinct fusogenicity and infectivity. Here, we find that the low fusogenicity of ENTV envelope protein (Env) is not because of receptor binding, but lies in its intrinsic insensitivity to receptor-mediated triggering for fusion at low pH. Distinct from JSRV, shedding of ENTV surface (SU) subunit into culture medium was not enhanced by a soluble form of receptor, Hyal2 (sHyal2), and sHyal2 was unable to effectively inactivate the ENTV pseudovirions. Remarkably, replacing either of the two amino acid residues, N191 or S195, located in the ENTV SU with the corresponding JSRV residues, H191 or G195, markedly increased the Env-mediated membrane fusion activity and infection. Reciprocal amino acid substitutions also partly switched the sensitivities of ENTV and JSRV pseudovirions to sHyal2-mediated SU shedding and inactivation. While N191 is responsible for an extra N-linked glycosylation of ENTV SU relative to that of JSRV, S195 possibly forms a hydrogen bond with a surrounding amino acid residue. Molecular modeling of the pre-fusion structure of JSRV Env predicts that the segment of SU that contains H191 to G195 contacts the fusion peptide and suggests that the H191N and G195S changes seen in ENTV may stabilize its pre-fusion structure against receptor priming and therefore modulate fusion activation by Hyal2. In summary, our study reveals critical determinants in the SU subunits of JSRV and ENTV Env proteins that likely regulate their local structures and thereby differential receptor-mediated fusion activation at low pH, and these findings explain, at least in part, their distinct viral infectivity. [Copyright &y& Elsevier]

Hanzhou Citizen Center is a complex connected tall building, in which six hexadic-towers are connected to each other through six skybridges. The finite element model updating of the steel skybridge was conducted using the sensitivity-based and Bayesian estimation updating methods. The relative error of the frequencies and Modal Assurance Criterion (MAC) values of the modal shapes were firstly computed, then the dynamic characteristic differences between numerical model and real structure were obtained by comparing the calculated modal parameters and the estimated modal parameters through dynamic testing under the ambient excitation. The sensitivity matrix was constructed through differential computation for modal parameters with respect to all selected structural parameters and then the insensitive parameters were sieved. The parameter weighting matrix and response weighting matrix were obtained using the Bayesian estimation method. Based on the confidence values of initial designed parameters, the allowable lower and upper bounds were applied for the parameters values. The iterative updating procedure was conducted according to the convergence criterion. From the updating results, it is, found that there was a good correlation between the dynamic characteristics of updated model and estimated dynamic characteristics through dynamic testing. The updated model can then be used for vibration control, response prediction and condition assessment of the skybridge in future. [ABSTRACT FROM AUTHOR]

Presents information on a study conducted examined the functional capabilities of human CYP4B1, with emphasis on biochemistry. Analysis of metabolic capabilities of functional human CYP4B1; Suggestion that Pro427 is a critical determinant of holoenzyme expression; Catalytic properties of human CYP4B1.

Ebola virus (EBOV) is a highly pathogenic filovirus that causes hemorrhagic fever in humans and animals. Here we provide evidence that cell–cell contact promotes infection mediated by the glycoprotein (GP) of EBOV. Interestingly, expression of EBOV GP alone, even in the absence of retroviral Gag-Pol, is sufficient to transfer a retroviral vector encoding Tet-off from cell to cell. Cell-to-cell infection mediated by EBOV GP is blocked by inhibitors of actin polymerization, but appears to be less sensitive to KZ52 neutralization. Treatment of co-cultured cells with cathepsin B/L inhibitors, or an entry inhibitor 3.47 that targets the receptor NPC1 for virus binding, also blocks cell-to-cell infection. Cell–cell contact also enhances spread of rVSV bearing GP in monocytes and macrophages, the primary targets of natural EBOV infection. Altogether, our study reveals that cell–cell contact promotes EBOV GP-mediated infection, and provides new insight into understanding EBOV spread and viral pathogenesis. [ABSTRACT FROM AUTHOR]

Despite remarkable advances in treatment, most patients with hepatocellular carcinoma (HCC) respond poorly to anti-programmed cell death 1 (anti-PD1) therapy. A deeper insight into the tolerance mechanism of HCC against this therapy is urgently needed. We performed next-generation sequencing, multiplex immunofluorescence, and dual-color immunohistochemistry and constructed an orthotopic HCC xenograft tumor model to identify the key gene associated with anti-PD1 tolerance. A spontaneously tumorigenic transgenic mouse model, an in vitro coculture system, mass cytometry, and multiplex immunofluorescence were used to explore the biological function of zinc finger protein 64 (ZFP64) on tumor progression and immune escape. Molecular and biochemical strategies like RNA-sequencing, chromatin immunoprecipitation-sequencing and mass spectrometry were used to gain insight into the underlying mechanisms of ZFP64. We showed that ZFP64 is frequently upregulated in tumor tissues from patients with anti-PD1-resistant HCC. Elevated ZFP64 drives anti-PD1 resistance by shifting macrophage polarization toward an alternative activation phenotype (M2) and fostering an inhibitory tumor microenvironment. Mechanistically, we primarily demonstrated that protein kinase C alpha (PKCα) directly phosphorylates ZFP64 at S226, leading to its nuclear translocation and the transcriptional activation of macrophage colony-stimulating factor (CSF1). HCC-derived CSF1 transforms macrophages to the M2 phenotype to drive immune escape and anti-PD1 tolerance. Notably, Gö6976, a protein kinase inhibitor, and lenvatinib, a multi-kinase inhibitor, reset the tumor microenvironment and restore sensitivity to anti-PD1 by blocking the PKCα/ZFP64/CSF1 axis. We propose that the PKCα/ZFP64/CSF1 axis is critical for triggering immune evasion and anti-PD1 tolerance. Inhibiting this axis with Gö6976 or lenvatinib overcomes anti-PD1 resistance in HCC. Despite remarkable treatment progress, most patients with hepatocellular carcinoma respond poorly to anti-PD1 therapy (a type of immunotherapy). A deeper insight into the tolerance mechanisms to this therapy is urgently needed. Herein, we unravel a previously unexplored mechanism linking tumor progression, macrophage polarization, and anti-PD1 resistance, and offer an attractive novel target for anti-PD1 combination therapy, which may benefit patients with hepatocellular carcinoma. [Display omitted] • ZFP64 is frequently upregulated in anti-PD1 resistant HCC. • PKCα/ZFP64/CSF1 axis is critical for triggering immune evasion and anti-PD1 tolerance. • Gö6976 and lenvatinib overcome anti-PD1 resistance by blocking the PKCα/ZFP64/CSF1 axis. • Gö6976 combined with anti-PD1 could be an effective new strategy in HCC therapy. [ABSTRACT FROM AUTHOR]

Modifications at the N-terminus of the rabbit CYP4B1 gene resulted in expression levels in Escherichia coli of up to 660 nmol/L. Solubilization of the enzyme from bacterial membranes led to substantial conversion to cytochrome P420 unless α-naphthoflavone was added as a stabilizing ligand. Mass spectrometry analysis and Edman sequencing of purified enzyme preparations revealed differential N-terminal post-translational processing of the various constructs expressed. Notably, bacterial expression of CYP4B1 produced a holoenzyme with >98.5% of its heme prosthetic group covalently linked to the protein backbone. The near fully covalently linked hemoproteins exhibited similar rates and regioselectivities of lauric acid hydroxylation to that observed previously for the partially heme processed enzyme expressed in insect cells. These studies shed new light on the consequences of covalent heme processing in CYP4B1 and provide a facile system for future mechanistic and structural studies with the enzyme. [Copyright &y& Elsevier]

Interferon-induced transmembrane (IFITM) proteins inhibit the entry of a large number of viruses. Not surprisingly, many viruses are refractory to this inhibition. In this study, we report that different strains of HIV and SIV are inhibited by human IFITM proteins to various degrees, with SIV of African green monkeys (SIV AGM ) being mostly restricted by human IFITM2. Interestingly, SIV AGM is as much inhibited by human IFITM2 as by IFITM3 of its own host African green monkeys. Our data further demonstrate that the entry of SIV AGM is impaired by human IFITM2 and that this inhibition is overcome by the cholesterol-binding compound amphotericin B that also overcomes IFITM inhibition of influenza A viruses. These results suggest that IFITM proteins exploit similar mechanisms to inhibit the entry of both pH-independent primate lentiviruses and the pH-dependent influenza A viruses. [ABSTRACT FROM AUTHOR]

Abstract: Nardokanshone A (1), a new type of sesquieterpenoid–chalcone hybird, with a 2,3-dihydrofuran ring fusing an aristolane-type sesquiterpenoid and a chalcone, along with its possible bioprecursor, kanshone C (2), together with four known flavones were isolated from Nardostachys chinensis. Their structures were elucidated by spectroscopic methods, and the absolute configuration of 1 was determined by quantum chemical DFT calculations. The possible biosynthetic pathway of 1 was also proposed. [Copyright &y& Elsevier]