Representative Members Research Articles

Microbial life in the grapevine: what can we expect from the leaf microbiome?

Aim: Recent studies have shown that plants harbor complex bacterial communities, the so-called “microbiome”. We are only beginning to unravel the origin of these bacterial plant inhabitants, their community structure and their roles, which, in analogy to the gut microbiome, are likely to be of essential nature. The aim of this work was to analyze the abundance and diversity of the cultivable members of the bacterial microbiome living in and on the leaves of grapevine, and to identify microbiome members with putative plant-protective activities against phytopathogenic organisms.Methods and results: Grapevine leaves were sampled three times during the growing season at one location and used to quantify the abundance and isolate representative members of the epiphytic and endophytic bacterial communities. Results were compared for three grapevine cultivars: Pinot noir, Chasselas and Solaris. Greater bacterial abundance and diversity was observed among epiphytes than among endophytes. Leaf imprints revealed a higher colonization density for the upper than for the lower surface of leaves. A high relative frequency of strains belonging to the genera Staphylococcus and Bacillus was observed, especially in the endophytic communities.Conclusions: The first results of this ongoing study led to the conclusion that epiphytic bacteria of the cultivable grapevine microbiome were more abundant and diverse than endophytic bacteria. A tendency towards more abundant bacteria in the resistant variety Solaris than in the susceptible varieties Chasselas and Pinot noir contrasted with a higher diversity of epiphytic bacteria in the Pinot noir variety. A trend for higher frequency of strains showing antagonistic activity towards the grapevine pathogen Botrytis cinerea among isolates from the resistant variety Solaris could indicate a putative contribution of microbiome bacteria to this resistant phenotype, even though this remains to be confirmed.Significance and impact of the study: This study constitutes a first step in characterizing the endo- and epiphytic cultivable bacterial communities of three grapevine varieties grown at the same location. Further, presently ongoing studies shall reveal i) the true complexity of these leaf-associated communities through cultivation-independent, next generation sequencing techniques, and ii) their potential as a source of biofungicidal agents. In this last point, the contribution of the emission of volatile organic compounds (VOCs) as a newly discovered type of bacterial weapon against fungal and oomycetal pathogens shall be quantified.

Members of the GalNAc-T family of enzymes utilize distinct Golgi localization mechanisms.

Mucin-type O-glycosylation is an evolutionarily conserved and essential post-translational protein modification that is initiated in the Golgi apparatus by a family of enzymes known as the UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferases (GalNAc-Ts). GalNAc-Ts are type II membrane proteins which contain short N-terminal tails located in the cytoplasm, a transmembrane domain that crosses the Golgi membrane, to which is connected a stem region that tethers the C-terminal catalytic and lectin domains that reside in the Golgi lumen. Although mucin-type O-glycans have been shown to play critical roles in numerous biological processes, little is known about how the GalNAc-Ts are targeted to their site of action within the Golgi complex. Here, we investigate the essential protein domains required for Golgi localization of four representative members of the GalNAc-T family of enzymes. We find that GalNAc-T1 and -T2 require their cytoplasmic tail and transmembrane domains for proper Golgi localization, while GalNAc-T10 requires its transmembrane and luminal stem domains. GalNAc-T7 can use either its cytoplasmic tail or its luminal stem, in combination with its transmembrane domain, to localize to the Golgi. We determined that a single glutamic acid in the GalNAc-T10 cytoplasmic tail inhibits its ability to localize to the Golgi via a cytoplasmic tail-dependent mechanism. We therefore demonstrate that despite their similarity, different members of this enzyme family are directed to the Golgi by more than one set of targeting signals.

The in vitro Antiviral Mechanisms of Stronger Neo-Minophafen C, an Established Formulation of Compound Glycyrrhizin

Background: Glycyrrhiza glabra (liquorice) has been extensively used since ancient Egypt, Greek and Roman, and is an important herb in traditional Chinese medicine. Its major compound, Glycyrrhizin (GL) possesses multiple pharmacological activities, such as anti-virus waiting for exploration indepth. Objective: The aim of this research is determining the antiviral mechanisms of Stronger Neo-Minophafen C (SNMC), an established formulation of compound GL based on Interferon (IFN) system, an important cytokine family best known for its antiviral ability. Methods: Four cell lines, A549, Hela, SMMC-7721 and TC-1, were recruited. The relative cell viability (RCV) was measured with 3(4, 5 dimethylthiazol) 2, 5 diphenyltetrazolium bromide (MTT). The gene transcription of key elements on IFN system, such as IFN-β1, IRF3 and ISG15 were evaluated using realtime RT-PCR. The expressions of key enzymes on IFN system were measured by Western blot. The concentrations of IFN-γ and IRF1, representative members of type II interferon, were detected by ELISA. Results: SNMC reduces RCV with concurrent induction of antiviral genes majorly belong to type I IFN pathway, focusing on IRF3-IFN-β1- ISG15 axis. The expression of IFN-β1, IRF3 and ISG15 genes in A549 and Hela cells peak at 12 h post-SNMC incubation, in a time- and dosage- dependent manner. The expression of IFN-β1 protein reaches a peak at 24 h in A549 and SMMC-7721 cells, and peaks at 48 h in Hela and TC-1 cells. The expression of ISG15 reaches a peak at 24 h in A549, Hela and TC-1 cells, and at 48 h in SNMC-7721 cells. The expression of Mx reaches a peak at 24 h in A549 and Hela cells, and at 48 h in SMMC-7721 and TC-1 cells. However, SNMC could not induce the expression of type II IFN signal pathway. Conclusion: We demonstrated that SNMC can induce the expression of important anti-viral genes in type I interferon pathway and indicate the existence of a key pathway response for the anti-viral effects of SNMC.

Molecular systematics of sturgeon nucleocytoplasmic large DNA viruses

Namao virus (NV) is a sturgeon nucleocytoplasmic large DNA virus (sNCLDV) that can cause a lethal disease of the integumentary system in lake sturgeon Acipenser fulvescens. As a group, the sNCLDV have not been assigned to any currently recognized taxonomic family of viruses. In this study, a data set of NV DNA sequences was generated and assembled as two non-overlapping contigs of 306,448 bp and then used to conduct a comprehensive systematics analysis using Bayesian inference of phylogeny for NV, other sNCLDV and representative members of six families of the NCLDV superfamily. The phylogeny of NV was reconstructed using protein homologues encoded by nine nucleocytoplasmic virus orthologous genes (NCVOGs): NCVOG0022 – mcp, NCVOG0038 – DNA polymerase B elongation subunit, NCVOG0076 – VV A18-type helicase, NCVOG0249 – VV A32-type ATPase, NCVOG0262 – AL2 VLTF3-like transcription factor, NCVOG0271 – RNA polymerase II subunit II, NCVOG0274 – RNA polymerase II subunit I, NCVOG0276 – ribonucleotide reductase small subunit and NCVOG1117 – mRNA capping enzyme. The accuracy of our phylogenetic method was evaluated using a combination of Bayesian statistical analysis and congruence analysis. Stable tree topologies were obtained with data sets differing in target molecule(s), sequence length and taxa. Congruent topologies were obtained in phylogenies constructed using individual protein data sets. The major capsid protein phylogeny inferred that ten representative sNCLDV form a monophyletic group comprised of four lineages within a polyphyletic Mimi-Phycodnaviridae group of taxa. Overall, the analyses revealed that Namao virus is a member of the Mimiviridae family with strong and consistent support for a clade containing NV and CroV as sister taxa.

Discovery, Synthesis, Pharmacological Profiling, and Biological Characterization of Brintonamides A-E, Novel Dual Protease and GPCR Modulators from a Marine Cyanobacterium.

Five novel modified linear peptides named brintonamides A-E (1-5) were discovered from a marine cyanobacterial sample collected from Brinton Channel, Florida Keys. The total synthesis of 1-5 in addition to two other structurally related analogues (6 and 7) was achieved, which provided more material to allow rigorous biological evaluation and SAR studies. Compounds were subjected to cancer-focused phenotypic cell viability and migration assays and orthogonal target-based pharmacological screening platforms to identify their protease and GPCR modulatory activity profiles. The cancer related serine protease kallikrein 7 (KLK7) was inhibited to similar extents with an IC50 near 20 μM by both representative members 1 and 4, which differed in the presence or lack of the N-terminal unit. In contrast to the biochemical protease profiling study, clear SAR was observed in the functional GPCR screens, where five GPCRs in antagonist mode (CCR10, OXTR, SSTR3, TACR2) and agonist mode (CXCR7) were modulated by compounds 1-7 to varying extents. Chemokine receptor type 10 (CCR10) was potently modulated by brintonamide D (4) with an IC50 of 0.44 μM. We performed in silico modeling to understand the structural basis underlying the differences in the antagonistic activity among brintonamides toward CCR10. Because of the significance of KLK7 and CCR10 in cancer progression and metastasis, we demonstrated the ability of brintonamide D (4) at 10 μM to significantly target downstream cellular substrates of KLK7 (Dsg-2 and E-cad) in vitro and to inhibit CCL27-induced CCR10-mediated proliferation and the migration of highly invasive breast cancer cells.

Persistence of infectious Enterovirus within free-living amoebae – A novel waterborne risk pathway?

Free-living amoebae (FLA) are phagocytic protozoa found in natural and engineered water systems. They can form disinfectant-resistant cysts, which can harbor various human pathogenic bacteria, therefore providing them with a means of environmental persistence and dispersion through water distribution and other engineered water systems. The association of FLA with human viruses has been raised, but the limited data on the persistence of infectious virions within amoebae leaves this aspect unresolved. Enteroviruses can cause a wide range of illness and replicate in human respiratory and gastrointestinal tracts, both of which could be exposed through contact with contaminated waters if virus detection and removal are compromised by virion internalization in free-living protozoa. This is especially problematic for high-risk contaminants, such as coxsackieviruses, representative members of the Enterovirus genus that are likely infectious at low doses and cause a variety of symptoms to a vulnerable portion of the population (particularly infants). To investigate Enterovirus persistence within free-living amoebae we co-cultured an infectious clinical coxsackievirus B5 (CVB5) isolate, with the commonly reported tap water amoeba Vermamoeba vermiformis, after which we tracked virus localization and persistence in co-culture over time through a combination of advanced imaging, molecular and cell culture assays. Our results clearly demonstrate that infectious CVB5 can persist in all life stages of the amoebae without causing any visible injury to them. We also demonstrated that the amoeba generated vesicles containing virions that were expelled into the bulk liquid surroundings, a finding previously described for FLA-bacteria interactions, but not for FLA and human pathogenic viruses. Therefore, our findings suggest that the ability of CVB5 to persist in V. vermiformis could be a novel waterborne risk pathway for the persistence and dispersion of infectious human enteric viruses through water systems.

Abstract 4851: Potent cell cycle inhibitors suitable for treatment of multidrug-resistant tumors

Abstract We have developed a class of small-molecule cytotoxic compounds that are highly potent in an in vitro tubulin polymerization assay. Preclinical studies show that these drug candidates are potent against a range of cancer cell lines and may be well suited for the treatment of hematologic or solid tumors resistant to existing chemotherapy agents. We will present data on representative members of this class that inhibit cancer cell growth at nanomolar concentrations and are potent against a variety of cancer cell lines, including liver, breast, ovarian, and lung. The compounds induce cell cycle arrest in the G2M state within 24 hours with cell death occurring over multiple days. These tubulin inhibitors also behave as potent antiangiogenesis agents and inhibit endothelial tube formation in HUVEC cells at nanomolar concentrations. Functional assays using efflux pump inhibitors show that, compared to many major chemotherapy agents, our class of drug candidates is significantly less affected by the efflux pumps MDR1 and MRP1, which are commonly overexpressed as a mechanism of multidrug resistance. Our compounds show comparable potency against wild-type and cell lines developed to be resistant to other cancer drugs, while the potency of clinically relevant compounds such as paclitaxel or doxorubicin is reduced between 80x and about 3000x in the same assay. This feature suggests that our tubulin inhibitors may be active against tumors that are resistant to common cancer drugs. Overexpression of the β-III isotype of tubulin, which is known to occur in many aggressive and metastatic tumors, is another clinically relevant mechanism of resistance to microtubule-targeting anticancer agents. It has been correlated with significantly lower response to docetaxel-based chemotherapy in a number of cancers and is considered an indicator of resistance to paclitaxel and vinorelbine. We will present preclinical data showing that our compounds have similar activity against cells showing normal levels and those highly overexpressing β-III tubulin. The compounds display good in vitro physicochemical properties as well as favorable in vivo pharmacokinetics. In addition, we will present in vivo tolerability and efficacy data in mice. The ability of this class of tubulin inhibitors to maintain their efficacy across multiple drug-resistant cancer cell lines makes them attractive candidates for development as chemotherapy agents. In particular, a new anticancer agent that is less susceptible to major transporters and retains its potency when β-III tubulin is overexpressed could lead to more effective precision second-line therapy. Citation Format: Mohan Sivaraja, Sivan Sizikov, Nilantha Sirisoma, Tamari Kirtadze, Madhuri Chattopadhyay, Makena Ewald, Subhadra Dash, Anne Wong, Georg Neckermann, Elaine To, Stephanie Chang, Timothy P. Shiau, David C. Williams, Kevin M. Short, Angels Estiarte, Anirban Datta, David B. Kita. Potent cell cycle inhibitors suitable for treatment of multidrug-resistant tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4851.

Abstract 681: Targeting diacylglycerol kinases for immuno-oncology

Abstract Diacylglycerol kinases (DGKs) are integral components of signal transduction cascades that regulate cell biology through phosphorylation of the ubiquitous secondary messenger diacylglycerol. Emerging clinical evidence supports DGK-alpha (DGKA) as a promising target for cancer immunotherapy because of its critical role in regulating lipid signaling necessary for proper T cell activation. Methods for direct evaluation of DGK activity in native biologic systems are lacking and needed to develop chemical probes for studying isoform-specific functions. Here, I will discuss efforts from my group to utilize ATP acyl phosphate activity-based probes and quantitative mass spectrometry to map previously undefined ATP- and small molecule-binding sites of representative members from all subtypes of the DGK family. We use our chemical proteomics strategy to discover an unusual binding mode for DGKA inhibitors, including interactions at a novel binding site remote from the ATP binding pocket. I will also describe our efforts towards discovery of new lead inhibitors for future development of highly potent and selective DGKA inhibitors. Collectively, our studies illustrate the power of chemical proteomics to site-specifically profile protein-small molecule interactions and reveal key ligand binding sites for selective inactivation of the DGK family of lipid kinases. Citation Format: Ku-Lung Hsu, Hsu Lab at the University of Virginia. Targeting diacylglycerol kinases for immuno-oncology [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 681.

Six New neo-Clerodane Diterpenoids from Aerial Parts of Scutellaria barbata and Their Cytotoxic Activities.

Six new neo-clerodane diterpenoids (1: -6: ), scutebatas X - Z, A1-C1, along with twelve known ones (7: -18: ) were obtained via the phytochemical investigation of the aerial parts of Scutellaria barbata. Their structures were established by detailed spectroscopic analysis. The absolute configurations of 1: and 2: , as the representative members of this type, were identified based on a circular dichroic exciton chirality method. Moreover, in vitro cytotoxicity of compounds 1: -6: were evaluated against three human cancer cell lines (SGC-7901, MCF-7, and A-549) using the MTT method. Compound 6: showed cytotoxic activities against all the three cell lines with IC50 values of 17.9, 29.9, and 35.7 µM, respectively.

Stable, Well-Defined Nickel(0) Catalysts for Catalytic C-C and C-N Bond Formation.

The synthesis and catalytic activity of several classes of NHC-Ni(0) pre-catalysts stabilized by electron-withdrawing alkenes are described. Variations in the structure of fumarate and acrylate ligands modulate the reactivity and stability of the NHC-Ni(0) pre-catalysts and lead to practical and versatile catalysts for a variety of transformations. The catalytic activity and efficiency of representative members of this class of catalysts have been evaluated in reductive couplings of aldehydes and alkynes and in N-arylations of aryl chlorides.

Fertility Preservation for Patients with Malignant Disease. Guideline of the DGGG, DGU and DGRM (S2k-Level, AWMF Registry No. 015/082, November 2017) - Recommendations and Statements for Girls and Women.

Aim The aim of this official guideline published by the German Society of Gynecology and Obstetrics (DGGG) and coordinated with the German Society of Urology (DGU) and the German Society of Reproductive Medicine (DGRM) is to provide consensus-based recommendations, obtained by evaluating the relevant literature, on counseling and fertility preservation for prepubertal girls and boys as well as patients of reproductive age. Statements and recommendations for girls and women are presented below. Statements or recommendations for boys and men are not the focus of this guideline. Methods This S2k guideline was developed at the suggestion of the guideline commission of the DGGG, DGU and DGRM and represents the structured consensus of representative members from various professional associations (n = 40). Recommendations The guideline provides recommendations on counseling and fertility preservation for women and girls which take account of the patientʼs personal circumstances, the planned oncologic therapy and the individual risk profile as well as the preferred approach for selected tumor entities.

Methyl NMR spectroscopy: Measurement of dynamics in viral RNA-directed RNA polymerases.

Measurement of nuclear spin relaxation provides a powerful approach to access information about biomolecular conformational dynamics over several orders of magnitude in timescale. In several cases this knowledge in combination with spatial information from three-dimensional structures yields unique insight into protein stability and the kinetics and thermodynamics of their interactions and function. However, due to intrinsic difficulties in studying large systems using solution state nuclear magnetic resonance (NMR) approaches, until recently these measurements were limited to small-to-medium-sized systems. However, the development of a wide range of novel strategies that allow the selective isotope labeling of methyl groups in proteins have allowed the exploitation of the unique relaxation properties of this spin-system. This has in turn enabled the extension of NMR approaches to high molecular weight proteins including a variety of enzymes and their complexes. Here, we recount our experiences in obtaining assignments of the methyl resonances for two representative members of a class of RNA-directed RNA polymerases (RdRps) encoded by bacteriophages of the Cystoviridae family. We demonstrate the utility of these methyl probes, limited in number for one case and more numerous for the other, to investigate the conformational dynamics of RdRps on the fast (ps-ns) and slow (μs-ms) timescales.

Porcine Deltacoronavirus Engages the Transmissible Gastroenteritis Virus Functional Receptor Porcine Aminopeptidase N for Infectious Cellular Entry.

Identification of cellular receptors used by coronavirus (CoV) entry into the host cells is critical to an understanding of pathogenesis and to development of intervention strategies. The fourth CoV genus, Deltacoronavirus, evolutionarily related to the Gammacoronavirus, has just been defined recently. In the current study, we demonstrate that porcine aminopeptidase N (pAPN) acts as a cross-genus CoV functional receptor for both enteropathogenic porcine deltacoronovirus (PDCoV) and alphacoronovirus (AlphaCoV) (transmissible gastroenteritis virus [TGEV]) based upon three lines of evidence. First, the soluble S1 protein of PDCoV bound to the surface of target porcine cell lines known to express pAPN as efficiently as TGEV-S1, which could be blocked by soluble pAPN pretreatment. Second, both PDCoV-S1 and TGEV-S1 physically recognized and interacted with pAPN by coimmunoprecipitation in pAPN cDNA-transfected cells and by dot blot hybridization assay. Finally, exogenous expression of pAPN in refractory cells conferred susceptibility to PDCoV-S1 binding and to PDCoV entry and productive infection. PDCoV-S1 appeared to have a lower pAPN-binding affinity and likely consequent lower infection efficiency in pAPN-expressing refractory cells than TGEV-S1, suggesting that there may be differences between these two viruses in the virus-binding regions in pAPN. This study paves the way for dissecting the molecular mechanisms of PDCoV-host interactions and pathogenesis as well as facilitates future vaccine development and intervention strategies against PDCoV infection.IMPORTANCE The emergence of new human and animal coronaviruses is believed to have occurred through interspecies transmission that is mainly mediated by a species-specific receptor of the host. Among the four genera of the Coronavirinae, a couple of functional receptors for the representative members in the genera Alphacoronavirus and Betacoronavirus have been identified, whereas receptors for Gammacoronavirus and Deltacoronavirus, which are believed to originate from birds, are still unknown. Porcine coronaviruses, including the newly discovered porcine deltacoronavirus (PDCoV) associated with diarrhea in newborn piglets, have posed a serious threat to the pork industry in Asia and North America. Here, we report that PDCoV employs the alphacoronavirus TGEV functional receptor porcine aminopeptidase N (pAPN) for cellular entry, demonstrating the usage of pAPN as a cross-genus CoV functional receptor. The identification of the PDCoV receptor provides another example of the expanded host range of CoV and paves the way for further investigation of PDCoV-host interaction and pathogenesis.

Complete mitochondrial genomes of six species of the freshwater red algal order Batrachospermales (Rhodophyta)

Only two mitochondrial (mt) genomes had been reported in members of the red algal order Batrachospermales, which are confined to freshwater habitats. Additional mt genomes of six representative members (Batrachospermum macrosporum, Kumanoa ambigua, K. mahlacensis, Paralemanea sp., Sheathia arcuata, and Sirodotia delicatula) were sequenced aiming to gain insights on the evolution of their mt genomes from a comparative analysis with other red algal groups. Mt genomes sequenced had the following characteristics: lengths ranging between 24,864 nt and 29,785 nt, 22 to 26 protein-coding genes, G + C contents of 21.3 to 30.7%, number of tRNA of 16 to 37, non-coding DNA from 3.8% to 14.8%. Comparative analysis revealed that mt genomes in Batrachospermales are highly conserved in terms of genome size and gene content and synteny. Phylogenetic analyses based on COI nucleotide data revealed high bootstrap support only for the genera usually recovered in the phylogenetic analyses but no support for supra-generic groups. The insertion of a group II intron carrying an ORF coding for the corresponding intron maturase interrupting the COI gene was observed in Paralamenea sp. and accounted for its larger genome in comparison to the other Batrachospermales mt genomes.

Inverted allosteric coupling between activation and inactivation gates in K+ channels.

The selectivity filter and the activation gate in potassium channels are functionally and structurally coupled. An allosteric coupling underlies C-type inactivation coupled to activation gating in this ion-channel family (i.e., opening of the activation gate triggers the collapse of the channel's selectivity filter). We have identified the second Threonine residue within the TTVGYGD signature sequence of K+ channels as a crucial residue for this allosteric communication. A Threonine to Alanine substitution at this position was studied in three representative members of the K+-channel family. Interestingly, all of the mutant channels exhibited lack of C-type inactivation gating and an inversion of their allosteric coupling (i.e., closing of the activation gate collapses the channel's selectivity filter). A state-dependent crystallographic study of KcsA-T75A proves that, on activation, the selectivity filter transitions from a nonconductive and deep C-type inactivated conformation to a conductive one. Finally, we provide a crystallographic demonstration that closed-state inactivation can be achieved by the structural collapse of the channel's selectivity filter.

PP4 - Consumer Preferences for Precision Medicine Technologies: Evidence from A Discrete Choice Experiment

Challenges to precision medicine implementation include a lack of evidence on preference-based utility in context to clinical validity and uncertain health outcomes. We address these challenges by eliciting patients’ preferences for the types of health and non-health outcomes arising from genomic testing. We used a sequential mixed methods approach. Qualitative research (n=20 patients) identified the following attributes: genetic test type (disease risk, treatment prediction), probability of having a biomarker, expert agreement on changing care based on genomics, quality of life gains, life expectancy gains with statistical uncertainty, and cost. Discrete-choice methodology enumerated preferences with a view to predict uptake and estimate willingness-to-pay (WTP). The population was a probability-based sample of the U.S. public. Error component mixed logit modeling enabled analysis of realistic substitution patterns. We validate our results by predicting the uptake of a 21-gene breast cancer recurrence risk test and comparing that with real-world estimates. 1124 representative members of the public who had recently seen a doctor completed the survey. Respondent’s had disutility if there was low medical expert agreement, if there was no or little change in quality or quantity-of-life, and as out-of-pocket costs increased. Respondents distinguished between high and low degrees of statistical uncertainty. Average WTP to decrease uncertainty was between $147 and $223, with higher WTP associated with resolving uncertainty for life-year gains of 3 months and lower WTP for life-year gains of 4 years. The predicted uptake of the recurrence risk test was 21% in 2004. As clinical utility was demonstrated, predicted uptake was 45%. The correlation between our predictions and published uptake was 0.90. Preferences for genomic testing are significantly influenced by medical expert agreement and the degree of scientific uncertainty surrounding outcomes. These findings can be used to project a trajectory of demand as well as inform translational research.

Complete genome sequence of yam chlorotic necrosis virus, a novel macluravirus infecting yam.

The complete genome sequence of a novel member of the genus Macluravirus was determined from yam plants with chlorotic and necrotic symptoms in China. The genomic RNA consists of 8,261 nucleotides (nt) excluding the 3'-terminal poly(A) tail, containing one long open reading frame (ORF) encoding a large putative polyprotein of 2,627 amino acids. Its genomic structure is typical of macluraviruses, which lack the P1 protein, N-terminal HC-Pro, and D-A-G motif for aphid transmission that are found in potyviruses. The virus shares 56.3-63.8% sequence identity at the genome sequence level and 49.7-63.9% at the polyprotein sequence level with other members of the genus Macluravirus. Phylogenetic analysis based on the complete polyprotein sequence of representative members of the family Potyviridae clearly places the virus within the genus Macluravirus. These results suggest that the virus, tentatively named "yam chlorotic necrosis virus" (YCNV), should be considered a member of a novel species in the genus Macluravirus.

Antimicrobial effects of photodynamic therapy.

The microorganisms that cause infections are increasing their resistance to antibiotics. In this context, alternative treatments are necessary. The antimicrobial photodynamic therapy (aPDT) is a therapeutic modality based on photosensitizing molecules that end up generating reactive oxygen species that induce the destruction of the target cells when are irradiated with light of a suitable wavelength and at a proper dose. The cells targeted by aPDT are all types of microorganisms (bacteria, fungi and parasites) including viruses and has been proven effective against representative members of all of them. In the field of dermatology, aPDT has been tested with promising results in different infections such as chronic ulcers, acne, onychomycosis and other cutaneous mycoses, as well as in leishmaniasis. Therefore, it is presented as a possible treatment option against the agents that cause skin and/or mucous infections.

Serotonin Promotes Enterohemorrhagic Escherichia Coli Pathogenesis Through Altered AI‐2 Production by Gut Microbiota

The overall goal of this study is to investigate the cross‐talk between a host metabolite (serotonin), the commensal bacterial community, and a microbial signaling molecule (Autoinducer‐2; AI‐2), in the etiology of Enterohemorrhagic Escherichia coli (EHEC) infections. A broad range of microbial (e.g., AI‐2, indole) and host metabolites (e.g., neuroendocrine hormones such as serotonin and norepinephrine) are present in the GI tract microenvironment and often function together to modulate the virulence of enteric pathogens. Serotonin is of specific interest as it is abundant in the GI tract and has pleiotropic roles on intestinal physiology. While it is well established that serotonin levels increase during inflammation, its impact on the commensal microbiota composition and function, and thereby, on enteric pathogen infections is poorly understood. Here we show that serotonin exposure results in a statistically significant increase (p<0.05) in the production of AI‐2 produced by non‐pathogenic E. coli and EHEC. Serotonin exposure also increased the expression of virulence genes (eaeA, escC, and escV) in EHEC in vitro and this increase depends on the luxS gene that is required for AI‐2 production. Based on these results, we hypothesize that serotonin's effects on EHEC virulence are mediated through AI‐2. Administering serotonin in mice resulted in pronounced dysbiosis of the microbiota composition. Interestingly, approximately 50% of the bacterial communities that showed a significant fold change (p<0.05) at the genus level had representative members with the luxS gene. Significant changes were also observed in the levels of six tryptophan‐derived microbiota metabolites including a reduction in the levels of indole. Together, our results support a model in which an increase in serotonin causes microbiota dysbiosis, increases AI‐2 levels, downregulates the beneficial anti‐inflammatory metabolites, thereby creating a niche favorable for EHEC colonization. Understanding the specific mechanisms underlying the effect of serotonin on the microbial community can lead to the development of new therapeutic approaches for combating enteric infections.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Peripartum Haemorrhage, Diagnosis and Therapy. Guideline of the DGGG, OEGGG and SGGG (S2k Level, AWMF Registry No. 015/063, March 2016).

Purpose This is an official interdisciplinary guideline, published and coordinated by the German Society of Gynaecology and Obstetrics (DGGG), the Austrian Society of Gynaecology and Obstetrics (OEGGG) and the Swiss Society of Gynaecology and Obstetrics (SGGG). The guideline was developed for use in German-speaking countries and is backed by the German Society of Anaesthesiology and Intensive Medicine (DGAI), the Society of Thrombosis and Haemostasis Research (GTH) and the German Association of Midwives. The aim is to provide a consensus-based overview of the diagnosis and management of peripartum bleeding obtained from an evaluation of the relevant literature. Methods This S2k guideline was developed from the structured consensus of representative members of the various professional associations and professions commissioned by the Guideline Commission of the DGGG. Recommendations The guideline encompasses recommendations on definitions, risk stratification, prevention and management.