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Background & Aims: The spread of foot-and-mouth disease virus (FMDV) through aerosol droplets among cloven-hoofed ungulates in close contact is a major obstacle for successful animal husbandry. Therefore, the development of suitable mucosal vaccines, especially nasal vaccines, to block the virus at the initial site of infection is crucial., Patients and Methods: Here, we constructed eukaryotic expression plasmids containing the T and B-cell epitopes (pTB) of FMDV in tandem with the molecular mucosal adjuvant Fms-like tyrosine kinase receptor 3 ligand (Flt3 ligand, FL) (pTB-FL). Then, the constructed plasmid was electrostatically attached to mannose-modified chitosan-coated poly(lactic-co-glycolic) acid (PLGA) nanospheres (MCS-PLGA-NPs) to obtain an active nasal vaccine targeting the mannose-receptor on the surface of antigen-presenting cells (APCs)., Results: The MCS-PLGA-NPs loaded with pTB-FL not only induced a local mucosal immune response, but also induced a systemic immune response in mice. More importantly, the nasal vaccine afforded an 80% protection rate against a highly virulent FMDV strain (AF72) when it was subcutaneously injected into the soles of the feet of guinea pigs., Conclusions: The nasal vaccine prepared in this study can effectively induce a cross-protective immune response against the challenge with FMDV of same serotype in animals and is promising as a potential FMDV vaccine., Competing Interests: Declaration of competing interest The authors declare no competing interests, and manuscript is approved by all authors for publication. I would like to declare on behalf of my co-authors that the work described was original research that has not been published previously, and not under consideration for publication elsewhere, in whole or in part., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Endoplasmic reticulum aminopeptidase 1 (ERAP1) plays a key role in controlling the immunopeptidomes available for presentation by MHC (major histocompatibility complex) molecules, thus influences immunodominance and cell-mediated immunity. It carries out this critical function by a unique molecular ruler mechanism that trims antigenic precursors in a peptide-length and sequence dependent manner. Acting as a molecular ruler, ERAP1 is capable of concurrently binding antigen peptide N- and C-termini by its N-terminal catalytic and C-terminal regulatory domains, respectively. As such ERAP1 can not only monitor substrate's lengths, but also exhibit a degree of sequence specificity at substrates' N- and C-termini. On the other hand, it also allows certain sequence and length flexibility in the middle part of peptide substrates that is critical for shaping MHC restricted immunopeptidomes. Here we report structural and biochemical studies to understand the molecular details on how ERAP1 can accommodate side chains of different anchoring residues at the substrate's C-terminus. We also examine how ERAP1 can accommodate antigen peptide precursors with length flexibility. Based on two newly determined complex structures, we find that ERAP1 binds the C-termini of peptides similarly even with different substrate sequences and/or lengths, by utilizing the same hydrophobic specificity pocket to accommodate peptides with either a Phe or Leu as the C-terminal anchor residue. In addition, SPR (surface plasmon resonance) binding analyses in solution further confirm the biological significance of these peptide-ERAP1 interactions. Similar to the binding mode of MHC-I molecules, ERAP1 accommodates for antigenic peptide length difference by allowing the peptide middle part to kink or bulge at the middle of its substrate binding cleft. This explains how SNP coded variants located at the middle of ERAP1 substrate binding cleft would influence the antigen pool and an individual's susceptibility to diseases., (Copyright © 2021 Elsevier GmbH. All rights reserved.)

Coptis chinensis is a widely used traditional Chinese herbal medicine. In this work, 6 new alkaloids (coptisine A-F, 1-6) and 26 known alkaloids (7-32) were isolated from the chloroform extract of the rhizomes of C. chinensis. Compounds 1-3 are α-carbonylated benzylisoquinolines, and 4-6 are berberidic acid type alkaloids. Their structures were elucidated on the basis of extensive NMR and MS analyses. Seven compounds (7, 20, 22, 23, 25, 26, 29) exhibited significant AChE inhibitory activities at 10 μM (inhibition rates >80%)., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2019. Published by Elsevier B.V.)

Interruption of the Warburg effect - the observation that un-stimulated macrophages reprogram their core metabolism from oxidative phosphorylation toward aerobic glycolysis to become pro-inflammatory M1 macrophages upon stimulation - is an emerging strategy for the treatment of cancer and anti-inflammatory diseases such as rheumatoid arthritis. We studied this process with view to the discovery of novel therapeutics, and found that tylophorine-based compounds targeted a ribonucleoprotein complex containing caprin-1 and mRNAs of c-Myc and HIF-1α in LPS/IFN-γ stimulated Raw264.7 cells, diminished the protein levels of c-Myc and HIF-1α, and consequently downregulated their targeted genes that are associated with the Warburg effect, as well as the pro-inflammatory iNOS and COX2. The tylophorine-based compound DBQ 33b significantly meliorated the severity and incidence of type II collagen-monoclonal antibody-induced rheumatoid arthritis and diminished gene expressions of c-Myc, HIF-1α, iNOS, COX2, TNFα, and IL-17A in vivo. Moreover, pharmacological inhibition of either c-Myc or HIF-1α exhibited similar effects as the tylophorine-based compound DBQ 33b, even though inhibition of c-Myc reversed the induction of iNOS and COX2 in LPS/IFN-γ stimulated Raw264.7 cells to a lesser degree. Therefore, simultaneous inhibition of both c-Myc and HIF-1α is efficacious for anti-inflammation in vitro and in vivo and merits further study., Competing Interests: Declaration of Competing Interest The authors declare no conflict of interest., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Graphene quantum dots (GQDs) are synthesized by the method of high-temperature pyrolysis from marigold granules and subsequently nitrogen-doped graphene quantum dots (N-GQDs) are synthesized from ethylenediamine by hydrothermal treatment, which shows a strong blue emission with 7.84% quantum yield (QY). This will be used in detection of Fe 3+ in water environments and the field of bioimaging., (Copyright © 2019 Elsevier B.V. All rights reserved.)

A novel biphenyl-derived salicylhydrazone Schiff base (BSS) fluorescent probes for highly sensitive and selective identification of Cu 2+ has been synthesized. In addition, the recognition has been proved experimentally. The results indicated that the complex forms a 1:1 complex with Cu 2+ shows fluorescent quenching. Furthermore, the detection limit of 1.54×10 -8 M. More interesting, the probe BSS not only have a good biocompatibility in living cells, but also the sense behavior of Cu 2+ in the cell nucleus., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Cell proliferation, apoptosis, autophagy, oxidative stress and metabolic dysregulation are the basis of many diseases. Forkhead box transcription factor O1 (FOXO1) changes in response to cellular stimulation and maintains tissue homeostasis during the above-mentioned physiological and pathological processes. Substantial evidences indicate that FOXO1's function depends on the modulation of downstream targets such as apoptosis- and autophagy-associated genes, anti-oxidative stress enzymes, cell cycle arrest genes, and metabolic and immune regulators. In addition, oxidative stress, high glucose and other stimulations induce the regulation of FOXO1 activity via PI3k-Akt, JNK, CBP, Sirtuins, ubiquitin E3 ligases, etc., which mediate multiple signalling pathways. Subsequent post-transcriptional modifications, including phosphorylation, ubiquitination, acetylation, deacetylation, arginine methylation and O-GlcNAcylation, activate or inhibit FOXO1. The regulation of FOXO1 and its role might provide a significant avenue for the prevention and treatment of diseases. However, the subtle mechanisms of the post-transcriptional modifications and the effect of FOXO1 remain elusive and even conflicting in the development of many diseases. The determination of these questions potentially has implications for further research regarding FOXO1 signalling and the identification of targeted drugs., (Copyright © 2017. Published by Elsevier Inc.)

A new pyrazoline-based probe D was designed and synthesized, which can be used as a highly sensitive, selective and reversible recognizing fluorescent to detect Cu 2+ . The recognition properties of this compound was investigated by UV-vis absorption and fluorescence spectrophotometry. The results showed that the probe D forms a 1:1 complex with Cu 2+ and displayed a linear fluorescence response to Cu 2+ with a detection limit of 1.94×10 -7 M. In addition, the probe have a good biocompatibility in living cells., (Copyright © 2017 Elsevier B.V. All rights reserved.)

A reduced graphene oxide (RGO) based capacitive real time bio-sensor was presented. Suspended graphene oxide (GO) film was assembled electrophoretically between the source and drain electrodes of a transistor and then reduced by annealing in hydrogen/nitrogen forming gas to optimize the surface functional groups and conductivity. The resonance frequency of the transmission coefficient (S 21 ) of the transistor was observed to shift with deoxyribonucleic acid (DNA)-hybridization, with a detecting limit of ~5nM. The advantages of the bio-sensing approach include low-noise frequency output, solution based real time detection and capable of on-chip integration., (Copyright © 2016 Elsevier B.V. All rights reserved.)

As a very promising surface coating technology, atomic layer deposition (ALD) can be used to modify the surfaces of polymeric materials for improving their functions and expanding their application areas. Polymeric materials vary in surface functional groups (number and type), surface morphology and internal structure, and thus ALD deposition conditions that typically work on a normal solid surface, usually do not work on a polymeric material surface. To date, a large variety of research has been carried out to investigate ALD deposition on various polymeric materials. This paper aims to provide an in-depth review of ALD deposition on polymeric materials and its applications. Through this review, we will provide a better understanding of surface chemistry and reaction mechanism for controlled surface modification of polymeric materials by ALD. The integrated knowledge can aid in devising an improved way in the reaction between reactant precursors and polymer functional groups/polymer backbones, which will in turn open new opportunities in processing ALD materials for better inorganic/organic film integration and potential applications., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Alstonia scholaris has been used in "Dai" ethnic medicine to treat chronic respiratory diseases for a long history, and the major bioactive constituents are alkaloids. An alkaloidal extract of A. scholaris leaves (AAS) has been developed into an investigational new drug, and has been approved for phase I/II clinical trials by China Food and Drug Administration. However, little is known on the chemical composition and in vivo metabolism of AAS, thus far. In this study, an ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC/qTOF-MS) method was established to characterize the chemical constituents of AAS. Samples were separated on an ACQUITY UPLC CSH column (2.1×100mm, 1.7μm) with acetonitrile and water containing 0.3% formic acid as the mobile phase. On the basis of high-accuracy mass spectral analysis, a total of 35 alkaloids were characterized from AAS, including 11 scholaricine-type, 9 vallesamine-type, 12 picrinine-type, and 3 tubotaiwine-type alkaloids. Furthermore, the metabolic pathways of 4 representative alkaloids in rats were studied. They mainly undertook hydroxylation and glucuronidation reactions. Based on the above metabolic pathways, the metabolism of AAS (10mg/kg) in rats after oral administration was studied by LC/MS. A total of 33 compounds in plasma, 40 compounds in urine, and 38 compounds in feces were characterized. The results indicated that scholaricine-type alkaloids could get into circulation more readily than the other types. This is the first systematic study on chemical profiling and metabolites identification of AAS., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Due to a rapid increase in human population and development of neighborhood economy over the last few decades, nitrogen (N) and other nutrient inputs in Lake Dianchi drainage basin have increased dramatically, changing the lake's trophic classification from oligotrophic to eutrophic. Although human activities are considered as main causes for the degradation of water quality in the lake, a numerical analysis of the share of the effect of different anthropogenic factors is still largely unexplored. We use the net anthropogenic N input (NANI) method to estimate human-induced N inputs to the drainage basin from 1980 to 2010, which covers the period of dramatic socioeconomic and environmental changes. For the last three decades, NANI increased linearly by a factor of three, from 4700 kg km(-2)year(-1) in 1980 to 12,600 kg km(-2)year(-1) in 2010. The main reason for the rise of NANI was due to fertilizer N application as well as human food and animal feed imports. From the perspective of direct effects of food consumption on N inputs, contributions of drivers were estimated in terms of human population and human diet using the Logarithmic Mean Divisia Index (LMDI) factor decomposition method. Although human population density is highly correlated to NANI with a linear correlation coefficient of 0.999, human diet rather than human population is found to be the single largest driver of NANI change, accounting for 47% of total alteration, which illustrates that the role of population density in the change of NANI may be overestimated through simple relational analysis. The strong linear relationships (p<0.01) between NANI and total N concentrations in the lakes over time may indicate that N level in the lake is able to respond significantly to N inputs to the drainage basin., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Upconversion nanoparticles (UCNs) attract intensive attentions in biomedical applications. They have shown great potential in bioimaging, biomolecule detection, drug delivery, photodynamic therapy and cellular molecules interactions. Due to the anti-Stokes optical property and NIR excitation, UCNs overcome the drawbacks encountered in conventional luminescent biomarkers. High signal to noise ratio, low cytotoxicity and stable high throughput results are obtained using UCNs as luminescent labels or light triggers in biomedical applications. In this review article, the reason for choosing UCNs as biomedical agents, the progress of the UCNs development and case studies of their biomedical applications will be discussed., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Four new C18-diterpenoid alkaloids, weisaconitines A-D (1-4), were isolated from Aconitum weixiense. Based on extensive UV, IR, MS, 1D and 2D NMR analyses, their structures were elucidated as 8-O-ethyldolaconine (1), 4-demethylgenicunine B (2), 14-oxoaconosine (3), and 8-O-ethylaconosine (4). The analgesic activity of compound 4 was studied with CH3COOH-induced writhing model in mice. Compound 4 showed writhing inhibitions of 24% (50 mg/kg), 26% (100 mg/kg) and 34% (200 mg/kg), respectively, as compared to the reference drug aspirin (63%) at a dose of 200 mg/kg., (© 2013.)

Viroporins are a group of viral proteins that participate in viral replication cycles, including modification of membrane permeability and promotion of viral release. Although biological data have been accumulated on viroporion-like proteins of other viruses belonging to family Flaviviridae, the viroporin activity and membrane topology of p7 protein from classical swine fever virus (CSFV), a member of the genus Pestivirus of the family Flaviviridae, are largely unknown. In this study, sequence analysis of the primary structure of p7 polypeptide demonstrates that p7 contains two putative transmembrane regions connected by a short hydrophilic segment. Expression of p7 protein in Escherichia coli leads to the permeabilization of bacterial cells to small molecules. The p7 protein also enhances the permeability of mammalian cells, increasing the intracellular Ca(2+) concentration and the permeability of cells to the translation inhibitor Hygromycin B. This protein is an integral membrane protein and can form homo-oligomers. It mainly localizes to the ER at the early stage of the expression and can be transferred to the plasma membrane at the late stage of the expression. Detergent permeabilization assays confirmed that the p7 protein is a 2-pass transmembrane protein and its N and C termini are exposed to the ER lumen. Deletion analysis showed that amino acid residues 41-63 may be essential for the viroporin activity of the protein. Our studies demonstrate that CSFV p7 possesses properties commonly associated with viroporins, which could be a potential target for the development of a therapeutic intervention for classic swine fever virus infection., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Glycosylasparaginase belongs to a family of N-terminal nucleophile hydrolases that autoproteolytically generate their mature enzymes from single-chain protein precursors. Previously, based on a precursor structure paused at pre-autoproteolysis stage by a reversible inhibitor (glycine), we proposed a mechanism of intramolecular autoproteolysis. A key structural feature, a highly strained conformation at the scissile peptide bond, had been identified and was hypothesized to be critical for driving autoproteolysis through an N-O acyl shift. To examine this "twist-and-break" hypothesis, we report here a 1. 9-Å-resolution structure of an autoproteolysis-active precursor (a T152C mutant) that is free of inhibitor or ligand and is poised to undergo autoproteolysis. The current crystallographic study has provided direct evidence for the natural conformation of the glycosylasparaginase autocatalytic site without influence from any inhibitor or ligand. This finding has confirmed our previous proposal that conformational strain is an intrinsic feature of an active precursor., (Copyright © 2010. Published by Elsevier Ltd.)

Glycosylasparaginase (GA) plays an important role in asparagine-linked glycoprotein degradation. A deficiency in the activity of human GA leads to a lysosomal storage disease named aspartylglycosaminuria. GA belongs to a superfamily of N-terminal nucleophile hydrolases that autoproteolytically generate their mature enzymes from inactive single chain protein precursors. The side-chain of the newly exposed N-terminal residue then acts as a nucleophile during substrate hydrolysis. By taking advantage of mutant enzyme of Flavobacterium meningosepticum GA with reduced enzymatic activity, we have obtained a crystallographic snapshot of a productive complex with its substrate (NAcGlc-Asn), at 2.0 A resolution. This complex structure provided us an excellent model for the Michaelis complex to examine the specific contacts critical for substrate binding and catalysis. Substrate binding induces a conformational change near the active site of GA. To initiate catalysis, the side-chain of the N-terminal Thr152 is polarized by the free alpha-amino group on the same residue, mediated by the side-chain hydroxyl group of Thr170. Cleavage of the amide bond is then accomplished by a nucleophilic attack at the carbonyl carbon of the amide linkage in the substrate, leading to the formation of an acyl-enzyme intermediate through a negatively charged tetrahedral transition state.

We have used several complementary approaches to investigate the minimal contiguous sequence required for the in vitro self cleavage reaction performed by Neurospora VS RNA. Deletion analysis and site-directed mutagenesis revealed that only a single nucleotide is required upstream of the self-cleavage site, and that the identity of this nucleotide is not critical. This distinguishes VS RNA from all currently known ribozymes except hepatitis delta virus RNA. The shortest contiguous sequence capable of cleavage contains 153 nt downstream of the cleavage site. Linker insertion mutagenesis suggests that much of this downstream sequence is important for self-cleavage. Comparative sequence analysis of the VS plasmid from six natural isolates supports the importance in vivo of the minimal region determined by in vitro methods. Also, phylogenetic analysis raises the possibility of a recent horizontal transfer of the VS plasmid from Neurospora intermedia to Neurospora sitophila.

Homozygous familial hypercholesterolemia (FH) is a genetic disorder featuring a functional defect in cellular LDL receptors, marked elevation in circulating LDL concentrations, and premature atherosclerosis. The potential atherogenic role of apo B-containing lipoproteins other than LDL in this disease is indeterminate. We describe the quantitative and qualitative characteristics of Lp(a) as a function of apo(a) phenotype in a group of eight, unrelated homozygous FH patients. Plasma Lp(a) levels were significantly elevated (2.5-fold; mean 50 +/- 32 mg/dl) as compared to those in healthy subjects. The S2 isoform of apo(a) occurred most frequently (6 of eight patients); the rare B isoform presented in three patients. Plasma Lp(a) levels in homozygous FH did not correspond to those predicted by apo(a) phenotype. Analyses of the density distribution of Lp(a) and of Lp(a) particle size and heterogeneity as a function of density did not reveal any anomalies characteristic of homozygous FH. However, comparison of the hydrated density of Lp(a) particles as a function of apo(a) isoform content revealed a clear influence of isoform on this parameter; thus, in a B/S2 heterozygous patient, the density distribution of Lp(a) fractions containing isoform B alone, B and S2, and S2 alone, demonstrated that the apparent molecular weight of apo(a) plays a determining role in controlling the hydrated density and size of the resulting Lp(a) particle. Indeed, patients expressing the high molecular weight, S2 isoform uniformly displayed a dense form of Lp(a) (hydrated density approximately 1.055 g/ml). In subjects presenting two apo(a) isoforms, each isoform resided on distinct lipoprotein particles; in such cases, the plasma levels of the denser isoform predominated, suggesting differences in rates of formation, or rates of tissular catabolism, or in the plasma stability of the particles, or a combination of these mechanisms. Considered together, our data may be interpreted to suggest that the elevated circulating levels of Lp(a) in homozygous FH patients may reflect either an increased biosynthesis, or diminished catabolism via the cellular LDL receptor pathway, or a combination of both.

We have constructed novel transcription templates in which we have fused the late gene promoters of Escherichia coli phages lambda and 82 upstream from three different rho-independent transcription terminators. Using an in vitro transcription assay and an in vivo galactokinase expression assay, we find that the initial portion of the transcribed region significantly affects the efficiency of some downstream terminators. We have identified, by deletion, substitution and point mutation analysis, sequences responsible for these increased levels of factor-independent readthrough. Since these important sequences occur within about 30 nucleotides of the RNA start site, we suggest that the initial portion of the transcript can affect termination efficiency.

We describe the development of five murine monoclonal antibodies (14A12, 39A1, 53A9, 73A7, and 128A6) specific to human apolipoprotein[a] (Mr approximately 570,000), and their characterization by a number of procedures including cotitration, competition and inhibition enzyme-linked immunosorbent assays (ELISA), immunoblotting of native lipoproteins and of SDS-solubilized apolipoproteins electrophoresed in polyacrylamide gels, and dot immunobinding assays. The patterns of immunoreactivity of these antibodies were similar. Each reacted in ELISA assays and upon electroimmunoblotting with purified apo[a], with apo[a] liberated by reduction of Lp[a], and with delipidated Lp[a] solubilized in SDS, but by contrast, they reacted with native Lp[a] to a significant degree only upon electroimmunoblotting. No reactivity was seen with LDL-apoB-100 or with other apolipoproteins. The cross-reactivity of these antibodies with the homologous protein, plasminogen, was examined by comparison of the amount of plasminogen or apo[a] required for 50% inhibition of antibody binding to apo[a], and by an ELISA assay. The inhibition assay showed reactivity with plasminogen to be 37- to 50-fold lower than with apo[a], while dot immunobinding showed the lower limit of detection of plasminogen and of apo[a] to be approximately 320 and 31 micrograms, respectively. In an ELISA sandwich assay based on monoclonal antibodies LHLP-1, 14A12, and 53A9, the lower limit of Lp[a] detection (approximately 1 ng/ml protein) was about 100-fold less than that of plasminogen. Chemical modification of apo[a] revealed a significant contribution of arginine residues to the epitopes of 14A12, 39A1, and 53A9. Modification of cysteine residues with iodoacetamide was without effect, thereby distinguishing these antibodies from LHLP-1. Each antibody reacted with the six major size forms of apo[a] (Mr approximately 450,000-750,000) in immunoblots of human sera electrophoresed in SDS-polyacrylamide gels. Marked heterogeneity in apo[a] phenotype was detected and both single and double band phenotypes were observed in a randomized study. Cotitration and competition binding studies showed varying degrees of interaction between all five epitopes, with the exception of 128A6 which appeared to be independent of 39A1 and 53A9 (and vice versa). These data suggest that our five monoclonal antibodies recognize epitopes on apolipoprotein[a] that are exposed and accessible on the native Lp[a] particle. We conclude that our monoclonal antibodies recognize a specific region of apo[a], and that this region undergoes a conformational change upon adsorption of Lp[a] to plastic thereby diminishing epitope recognition.(ABSTRACT TRUNCATED AT 400 WORDS)