114 research outputs found
Exploiting Behavioral Consistence for Universal User Representation
User modeling is critical for developing personalized services in industry. A
common way for user modeling is to learn user representations that can be
distinguished by their interests or preferences. In this work, we focus on
developing universal user representation model. The obtained universal
representations are expected to contain rich information, and be applicable to
various downstream applications without further modifications (e.g., user
preference prediction and user profiling). Accordingly, we can be free from the
heavy work of training task-specific models for every downstream task as in
previous works. In specific, we propose Self-supervised User Modeling Network
(SUMN) to encode behavior data into the universal representation. It includes
two key components. The first one is a new learning objective, which guides the
model to fully identify and preserve valuable user information under a
self-supervised learning framework. The other one is a multi-hop aggregation
layer, which benefits the model capacity in aggregating diverse behaviors.
Extensive experiments on benchmark datasets show that our approach can
outperform state-of-the-art unsupervised representation methods, and even
compete with supervised ones.Comment: Preprint of accepted AAAI2021 pape
Diversity and expression of microRNAs in the filarial parasite, Brugia malayi
Human filarial parasites infect an estimated 120 million people in 80 countries worldwide causing blindness and the gross disfigurement of limbs and genitals. An understanding of RNA-mediated regulatory pathways in these parasites may open new avenues for treatment. Toward this goal, small RNAs from Brugia malayi adult females, males and microfilariae were cloned for deep-sequencing. From approximately 30 million sequencing reads, 145 miRNAs were identified in the B. malayi genome. Some microRNAs were validated using the p19 RNA binding protein and qPCR. B. malayi miRNAs segregate into 99 families each defined by a unique seed sequence. Sixty-one of the miRNA families are highly conserved with homologues in arthropods, vertebrates and helminths. Of those miRNAs not highly conserved, homologues of 20 B. malayi miRNA families were found in vertebrates. Nine B. malayi miRNA families appear to be filarial-specific as orthologues were not found in other organisms. The miR-2 family is the largest in B. malayi with 11 members. Analysis of the sequences shows that six members result from a recent expansion of the family. Library comparisons found that 1/3 of the B. malayi miRNAs are differentially expressed. For example, miR-71 is 5-7X more highly expressed in microfilariae than adults. Studies suggest that in C.elegans, miR-71 may enhance longevity by targeting the DAF-2 pathway. Characterization of B. malayi miRNAs and their targets will enhance our understanding of their regulatory pathways in filariads and aid in the search for novel therapeutics
RETRACTED: vB-ApyS-JF1, the First Trueperella pyogenes Phage, Shows Potential as an Alternative Treatment Strategy for Trueperella pyogenes Infections
Trueperella pyogenes (T. pyogenes) is an important opportunistic animal pathogen that causes huge economic losses to the animal husbandry industry. The emergence of bacterial resistance and the unsatisfactory effect of the vaccine have prompted investigators to explore alternative strategies for controlling T. pyogenes infection. Due to the ability of phages to kill multidrug-resistant bacteria, the use of phage therapy to combat multidrug-resistant bacterial infections has attracted attention. In this study, a T. pyogenes phage, vB-ApyS-JF1 (JF1), was isolated from sewage samples, and its whole genome and biological characteristics were elucidated. Moreover, the protective effect of phage JF1 on a mouse bacteremic model caused by T. pyogenes was studied. JF1 harbors a double-stranded DNA genome with a length of 90,130 bp (30.57% G + C). The genome of JF1 lacked bacterial virulence–, antibiotic resistance– and lysogenesis-related genes. Moreover, the genome sequence of JF1 exhibited low coverage (<6%) with all published phages in the NCBI database, and a phylogenetic analysis of the terminase large subunits and capsid indicated that JF1 was evolutionarily distinct from known phages. In addition, JF1 was stable over a wide range of pH values (3 to 11) and temperatures (4 to 50°C) and exhibited strong lytic activity against T. pyogenes in vitro. In murine experiments, a single intraperitoneal administration of JF1 30 min post-inoculation provided 100% protection for mice against T. pyogenes infection. Compared to the phosphate-buffered saline (PBS) treatment group, JF1 significantly (P < 0.01) reduced the bacterial load in the blood and tissues of infected mice. Meanwhile, treatment with phage JF1 relieved the pathological symptoms observed in each tissue. Furthermore, the levels of the inflammatory cytokines tumour necrosis factor-α (TNF-α), interferon-γ (IFN-γ), and interleukin-6 (IL-6) in the blood of infected mice were significantly (P < 0.01) decreased in the phage-treated group. Taken together, these results indicate that phage JF1 demonstrated great potential as an alternative therapeutic treatment against T. pyogenes infection
A Method for Generation Phage Cocktail with Great Therapeutic Potential
Background: Bacteriophage could be an alternative to conventional antibiotic therapy against multidrug-resistant bacteria. However, the emergence of resistant variants after phage treatment limited its therapeutic application. Methodology/Principal Findings: In this study, an approach, named ‘‘Step-by-Step’ ’ (SBS), has been established. This method takes advantage of the occurrence of phage-resistant bacteria variants and ensures that phages lytic for wild-type strain and its phage-resistant variants are selected. A phage cocktail lytic for Klebsiella pneumoniae was established by the SBS method. This phage cocktail consisted of three phages (GH-K1, GH-K2 and GH-K3) which have different but overlapping host strains. Several phage-resistant variants of Klebsiella pneumoniae were isolated after different phages treatments. The virulence of these variants was much weaker [minimal lethal doses (MLD).1.3610 9 cfu/mouse] than that of wild-type K7 countpart (MLD = 2.5610 3 cfu/mouse). Compared with any single phage, the phage cocktail significantly reduced the mutation frequency of Klebsiella pneumoniae and effectively rescued Klebsiella pneumoniae bacteremia in a murine K7 strain challenge model. The minimal protective dose (MPD) of the phage cocktail which was sufficient to protect bacteremic mice from lethal K7 infection was only 3.0610 4 pfu, significantly smaller (p,0.01) than that of single monophage. Moreover, a delayed administration of this phage cocktail was still effective in protection against K7 challenge. Conclusions/Significance: Our data showed that the phage cocktail was more effective in reducing bacterial mutatio
Three Capsular Polysaccharide Synthesis-Related Glucosyltransferases, GT-1, GT-2 and WcaJ, Are Associated With Virulence and Phage Sensitivity of Klebsiella pneumoniae
Klebsiella pneumoniae (K. pneumoniae) spp. are important nosocomial and community-acquired opportunistic pathogens, which cause various infections. We observed that K. pneumoniae strain K7 abruptly mutates to rough-type phage-resistant phenotype upon treatment with phage GH-K3. In the present study, the rough-type phage-resistant mutant named K7RR showed much lower virulence than K7. Liquid chromatography-tandem mass spectrometry (LC-MS-MS) analysis indicated that WcaJ and two undefined glycosyltransferases (GTs)- named GT-1, GT-2- were found to be down-regulated drastically in K7RR as compared to K7 strain. GT-1, GT-2, and wcaJ are all located in the gene cluster of capsular polysaccharide (CPS). Upon deletion, even of single component, of GT-1, GT-2, and wcaJ resulted clearly in significant decline of CPS synthesis with concomitant development of GH-K3 resistance and decline of virulence of K. pneumoniae, indicating that all these three GTs are more likely involved in maintenance of phage sensitivity and bacterial virulence. Additionally, K7RR and GT-deficient strains were found sensitive to endocytosis of macrophages. Mitogen-activated protein kinase (MAPK) signaling pathway of macrophages was significantly activated by K7RR and GT-deficient strains comparing with that of K7. Interestingly, in the presence of macromolecular CPS residues (>250 KD), K7(ΔGT-1) and K7(ΔwcaJ) could still be bounded by GH-K3, though with a modest adsorption efficiency, and showed minor virulence, suggesting that the CPS residues accumulated upon deletion of GT-1 or wcaJ did retain phage binding sites as well maintain mild virulence. In brief, our study defines, for the first time, the potential roles of GT-1, GT-2, and WcaJ in K. pneumoniae in bacterial virulence and generation of rough-type mutation under the pressure of bacteriophage
Multiancestry Genome-Wide Association Study of Lipid Levels Incorporating Gene-Alcohol Interactions
A person's lipid profile is influenced by genetic variants and alcohol consumption, but the contribution of interactions between these exposures has not been studied. We therefore incorporated gene-alcohol interactions into a multiancestry genome-wide association study of levels of high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and triglycerides. We included 45 studies in stage 1 (genome-wide discovery) and 66 studies in stage 2 (focused follow-up), for a total of 394,584 individuals from 5 ancestry groups. Analyses covered the period July 2014-November 2017. Genetic main effects and interaction effects were jointly assessed by means of a 2-degrees-of-freedom (df) test, and a 1-df test was used to assess the interaction effects alone. Variants at 495 loci were at least suggestively associated (P <1 x 10(-6)) with lipid levels in stage 1 and were evaluated in stage 2, followed by combined analyses of stage 1 and stage 2. In the combined analysis of stages 1 and 2, a total of 147 independent loci were associated with lipid levels at P <5 x 10(-8) using 2-df tests, of which 18 were novel. No genome-wide-significant associations were found testing the interaction effect alone. The novel loci included several genes (proprotein convertase subtilisin/kexin type 5 (PCSK5), vascular endothelial growth factor B (VEGFB), and apolipoprotein B mRNA editing enzyme, catalytic polypeptide 1 (APOBEC1) complementation factor (A1CF)) that have a putative role in lipid metabolism on the basis of existing evidence from cellular and experimental models.Peer reviewe
A multi-ancestry genome-wide study incorporating gene-smoking interactions identifies multiple new loci for pulse pressure and mean arterial pressure
Elevated blood pressure (BP), a leading cause of global morbidity and mortality, is influenced by both genetic and lifestyle factors. Cigarette smoking is one such lifestyle factor. Across five ancestries, we performed a genome-wide gene-smoking interaction study of mean arterial pressure (MAP) and pulse pressure (PP) in 129 913 individuals in stage 1 and follow-up analysis in 480 178 additional individuals in stage 2. We report here 136 loci significantly associated with MAP and/or PP. Of these, 61 were previously published through main-effect analysis of BP traits, 37 were recently reported by us for systolic BP and/or diastolic BP through gene-smoking interaction analysis and 38 were newly identified (P <5 x 10(-8), false discovery rate <0.05). We also identified nine new signals near known loci. Of the 136 loci, 8 showed significant interaction with smoking status. They include CSMD1 previously reported for insulin resistance and BP in the spontaneously hypertensive rats. Many of the 38 new loci show biologic plausibility for a role in BP regulation. SLC26A7 encodes a chloride/bicarbonate exchanger expressed in the renal outer medullary collecting duct. AVPR1A is widely expressed, including in vascular smooth muscle cells, kidney, myocardium and brain. FHAD1 is a long non-coding RNA overexpressed in heart failure. TMEM51 was associated with contractile function in cardiomyocytes. CASP9 plays a central role in cardiomyocyte apoptosis. Identified only in African ancestry were 30 novel loci. Our findings highlight the value of multi-ancestry investigations, particularly in studies of interaction with lifestyle factors, where genomic and lifestyle differences may contribute to novel findings.Peer reviewe
Synthesis and Antibacterial Activity of Polyoxometalates with Different Structures
A new inorganic-organic hybrid compound, [{Cu(phen)2}2(H4W12O40)], was synthesized, and its crystal structure was determined. The Keggin anion H4W12O404− was grafted with two coordination units {Cu(phen)2}, forming an electrically neutral molecule. The antibacterial activity of several polyoxometalate compounds with different anionic structures including the new compound was studied. The results show that the compound 1 can inhibit the growth of Enterococcus faecalis FA2 strains and that antibacterial activity of the polyoxometalate compounds is dependent with component elements of POM but is less relative with the anion structures
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