Sld5, A Subunit of the Heterotetrameric GINS Complex is Necessary for Normal Cell Cycle Progression and Genomic Stability

Sld5 is one component of the GINS heterotetrameric complex essential to DNA replication. Specifically, GINS is known for its integral role during the G1 to S phase transition in the cell cycle. The GINS complex is comprised of multiple subunits: Psf1, Psf2, Psf3 and Sld5, all of which are highly conserved in eukaryotes. During the initiation of S phase, GINS mediates the association of multiple proteins at replication origins. SLD5 plays a central role in the GINS complex through contact with both Psf1 and Psf2. Due to this pivotal role, Sld5 is the focus of our continuing investigation into the mechanisms of DNA replication and heterochromatin formation in Drosophila. Understanding Sld5 function has employed the use of several approaches. To recognize the range of protein interactions in which SLD5 participates we are using yeast two-hybrid analysis, confirming suspected interactions. In addition to interaction studies we are utilizing two recently identified mutant alleles of SLD5 to understand its function in vivo. These p-element insertion alleles result in the truncation of the Sld5 protein removing a large portion of the C-terminal beta domain in both mutants, a domain that is believed to play a role in facilitating interactions with other proteins. The arrest point determination of Sld5 was completed and shown to occur at the late embryo/early larval stage transition of the developing Drosophila. These homozygous lethal alleles of SLD5 are being used to understand the role of Sld5 in DNA replication through EdU incorporation assays. In addition, possible roles for Sld5 in chromosome biology are being examined. These methods include the analysis of the morphology of chromosomes in polytene tissues, larval brain tissues, and embryos. Roles of Sld5 within the cell cycle have been explored by quantitation of mitotic indexes using larval brain squashes with both alleles of Sld5 showing a marked increase in mitotic figures observed when compared to wild type. In addition, Embryo analysis has revealed severe mitotic defects including asynchrony, cell dropout, and anaphase bridges are presence upon division. Exploration of the Sld5 subunit will further the understanding of the GINS complex and its role in DNA replication, along with its possible roles in chromosome biology and its role in genome maintenance.  M.S

Viral sequence variation in chronic carriers of hepatitis C virus has a low impact on liver steatosis.: HCV variability and steatosis

International audienceMost clinical studies suggest that the prevalence and severity of liver steatosis are higher in patients infected with hepatitis C virus (HCV) genotype 3 than in patients infected with other genotypes. This may reflect the diversity and specific intrinsic properties of genotype 3 virus proteins. We analyzed the possible association of particular residues of the HCV core and NS5A proteins known to dysregulate lipid metabolism with steatosis severity in the livers of patients chronically infected with HCV. We used transmission electron microscopy to quantify liver steatosis precisely in a group of 27 patients, 12 of whom were infected with a genotype 3 virus, the other 15 being infected with viruses of other genotypes. We determined the area covered by lipid droplets in liver tissues and analyzed the diversity of the core and NS5A regions encoded by the viral variants circulating in these patients. The area covered by lipid droplets did not differ significantly between patients infected with genotype 3 viruses and those infected with other genotypes. The core and NS5A protein sequences of the viral variants circulating in patients with mild or severe steatosis were evenly distributed throughout the phylogenic trees established from all the collected sequences. Thus, individual host factors seem to play a much greater role than viral factors in the development of severe steatosis in patients chronically infected with HCV, including those infected with genotype 3 viruses

Impact of early enteral versus parenteral nutrition on mortality in patients requiring mechanical ventilation and catecholamines: study protocol for a randomized controlled trial (NUTRIREA-2)

BACKGROUND: Nutritional support is crucial to the management of patients receiving invasive mechanical ventilation (IMV) and the most commonly prescribed treatment in intensive care units (ICUs). International guidelines consistently indicate that enteral nutrition (EN) should be preferred over parenteral nutrition (PN) whenever possible and started as early as possible. However, no adequately designed study has evaluated whether a specific nutritional modality is associated with decreased mortality. The primary goal of this trial is to assess the hypothesis that early first-line EN, as compared to early first-line PN, decreases day 28 all-cause mortality in patients receiving IMV and vasoactive drugs for shock. METHODS/DESIGN: The NUTRIREA-2 study is a multicenter, open-label, parallel-group, randomized controlled trial comparing early PN versus early EN in critically ill patients requiring IMV for an expected duration of at least 48 hours, combined with vasoactive drugs, for shock. Patients will be allocated at random to first-line PN for at least 72 hours or to first-line EN. In both groups, nutritional support will be started within 24 hours after IMV initiation. Calorie targets will be 20 to 25 kcal/kg/day during the first week, then 25 to 30 kcal/kg/day thereafter. Patients receiving PN may be switched to EN after at least 72 hours in the event of shock resolution (no vasoactive drugs for 24 consecutive hours and arterial lactic acid level below 2 mmol/L). On day 7, all patients receiving PN and having no contraindications to EN will be switched to EN. In both groups, supplemental PN may be added to EN after day 7 in patients with persistent intolerance to EN and inadequate calorie intake. We plan to recruit 2,854 patients at 44 participating ICUs. DISCUSSION: The NUTRIREA-2 study is the first large randomized controlled trial designed to assess the hypothesis that early EN improves survival compared to early PN in ICU patients. Enrollment started on 22 March 2013 and is expected to end in November 2015. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01802099 (registered 27 February 2013)

Une vaste opération de sauvetage archéologique en cours à Balloy (Seine-et-Marne)

National audienc

Archéologie préventive dans les carrières de granulats de la Bassée (Seine-et-Marne)

Augereau Anne, Gouge Patrick, Mordant Daniel, Séguier Jean-Marc. Archéologie préventive dans les carrières de granulats de la Bassée (Seine-et-Marne). In: Bulletin de la Société préhistorique française, tome 91, n°3, 1994. pp. 179-181

Sld5 A Subunit of the Heterotetrameric GINS Complex is Necessary for Normal Cell Cycle Progression and Genomic Stability

Sld5 is one component of the GINS heterotetrameric complex essential to DNA replication. Specifically GINS is known for its integral role during the G1 to S phase transition in the cell cycle. The GINS complex is comprised of multiple subunits: Psf1 Psf2 Psf3 and Sld5 all of which are highly conserved in eukaryotes. During the initiation of S phase GINS mediates the association of multiple proteins at replication origins. SLD5 plays a central role in the GINS complex through contact with both Psf1 and Psf2. Due to this pivotal role Sld5 is the focus of our continuing investigation into the mechanisms of DNA replication and heterochromatin formation in Drosophila. Understanding Sld5 function has employed the use of several approaches. To recognize the range of protein interactions in which SLD5 participates we are using yeast two-hybrid analysis confirming suspected interactions. In addition to interaction studies we are utilizing two recently identified mutant alleles of SLD5 to understand its function in vivo. These p-element insertion alleles result in the truncation of the Sld5 protein removing a large portion of the C-terminal beta domain in both mutants a domain that is believed to play a role in facilitating interactions with other proteins. The arrest point determination of Sld5 was completed and shown to occur at the late embryo/early larval stage transition of the developing Drosophila. These homozygous lethal alleles of SLD5 are being used to understand the role of Sld5 in DNA replication through EdU incorporation assays. In addition possible roles for Sld5 in chromosome biology are being examined. These methods include the analysis of the morphology of chromosomes in polytene tissues larval brain tissues and embryos. Roles of Sld5 within the cell cycle have been explored by quantitation of mitotic indexes using larval brain squashes with both alleles of Sld5 showing a marked increase in mitotic figures observed when compared to wild type. In addition Embryo analysis has revealed severe mitotic defects including asynchrony cell dropout and anaphase bridges are presence upon division. Exploration of the Sld5 subunit will further the understanding of the GINS complex and its role in DNA replication along with its possible roles in chromosome biology and its role in genome maintenance.

Sld5, A Subunit of the Heterotetrameric GINS Complex is Necessary for Normal Cell Cycle Progression and Genomic Stability

Sld5 is one component of the GINS heterotetrameric complex essential to DNA replication. Specifically, GINS is known for its integral role during the G1 to S phase transition in the cell cycle. The GINS complex is comprised of multiple subunits: Psf1, Psf2, Psf3 and Sld5, all of which are highly conserved in eukaryotes. During the initiation of S phase, GINS mediates the association of multiple proteins at replication origins. SLD5 plays a central role in the GINS complex through contact with both Psf1 and Psf2. Due to this pivotal role, Sld5 is the focus of our continuing investigation into the mechanisms of DNA replication and heterochromatin formation in Drosophila. Understanding Sld5 function has employed the use of several approaches. To recognize the range of protein interactions in which SLD5 participates we are using yeast two-hybrid analysis, confirming suspected interactions. In addition to interaction studies we are utilizing two recently identified mutant alleles of SLD5 to understand its function in vivo. These p-element insertion alleles result in the truncation of the Sld5 protein removing a large portion of the C-terminal beta domain in both mutants, a domain that is believed to play a role in facilitating interactions with other proteins. The arrest point determination of Sld5 was completed and shown to occur at the late embryo/early larval stage transition of the developing Drosophila. These homozygous lethal alleles of SLD5 are being used to understand the role of Sld5 in DNA replication through EdU incorporation assays. In addition, possible roles for Sld5 in chromosome biology are being examined. These methods include the analysis of the morphology of chromosomes in polytene tissues, larval brain tissues, and embryos. Roles of Sld5 within the cell cycle have been explored by quantitation of mitotic indexes using larval brain squashes with both alleles of Sld5 showing a marked increase in mitotic figures observed when compared to wild type. In addition, Embryo analysis has revealed severe mitotic defects including asynchrony, cell dropout, and anaphase bridges are presence upon division. Exploration of the Sld5 subunit will further the understanding of the GINS complex and its role in DNA replication, along with its possible roles in chromosome biology and its role in genome maintenance

Declaração Universal sobre Bioética e Direitos Humanos e Resolução CNS 466/2012: análise comparativa

Resumo Este artigo objetiva realizar análise comparativa entre a Resolução 466/2012 do Conselho Nacional de Saúde e a Declaração Universal sobre Bioética e Direitos Humanos da Organização das Nações Unidas para a Educação, Ciências e Cultura, no contexto de pesquisas envolvendo seres humanos, para verificar se a resolução aborda os princípios preconizados pela declaração. Os resultados mostram que, enquanto o texto da declaração traz os princípios éticos do respeito à dignidade humana, além de questões biomédicas, biotecnológicas, sanitárias, sociais e ambientais, a resolução ainda é bastante influenciada pela bioética clínica e as práticas biomédicas. Observou-se ausência na resolução dos termos “solidariedade”, “responsabilidade”, “responsabilidade individual”, “diversidade” e “desenvolvimento social”. A declaração utiliza o termo “equidade”, enquanto a resolução apresenta apenas “redução de desigualdades”. Publicada sete anos após a assinatura da declaração, a norma brasileira possui mais conteúdo principialista do que o conteúdo abrangente e político da declaração

Synthesis of fluorinated C-mannopeptides as sialyl Lewisx mimics for E- and P-selectin inhibition.

International audienceThe synthesis of fluorinated C-mannopeptides and their evaluation as E- and P-selectin inhibitors is described. These molecules are difluorinated analogues of CH(2)-glycopeptides already reported to act as sLe(x) mimics. The alpha and beta anomers of these CF(2)-glycopeptides have been prepared, as well as their 1-hydroxy analogues which were present in solution as an equilibrium mixture of alpha- and beta-pyranose and alpha- and beta-furanose forms. These molecules showed inhibitory activities comparable to their CH(2) counterparts with a moderate influence of the pseudo-anomeric center configuration

Nicotinamide Riboside Preserves Cardiac Function in a Mouse Model of Dilated Cardiomyopathy

- Erratum in: Correction to: Nicotinamide Riboside Preserves Cardiac Function in a Mouse Model of Dilated Cardiomyopathy. [Circulation. 2018]- Comment in: Raising NAD in Heart Failure: Time to Translate? [Circulation. 2018]International audienceBackground: Myocardial metabolic impairment is a major feature in chronic heart failure. As the major coenzyme in fuel oxidation and oxidative phosphorylation and a substrate for enzymes signaling energy stress and oxidative stress response, nicotinamide adenine dinucleotide (NAD+) is emerging as a metabolic target in a number of diseases including heart failure. Little is known on the mechanisms regulating homeostasis of NAD+ in the failing heart.Methods: To explore possible alterations of NAD+ homeostasis in the failing heart, we quantified the expression of NAD+ biosynthetic enzymes in the human failing heart and in the heart of a mouse model of dilated cardiomyopathy (DCM) triggered by Serum Response Factor transcription factor depletion in the heart (SRFHKO) or of cardiac hypertrophy triggered by transverse aorta constriction. We studied the impact of NAD+ precursor supplementation on cardiac function in both mouse models.Results: We observed a 30% loss in levels of NAD+ in the murine failing heart of both DCM and transverse aorta constriction mice that was accompanied by a decrease in expression of the nicotinamide phosphoribosyltransferase enzyme that recycles the nicotinamide precursor, whereas the nicotinamide riboside kinase 2 (NMRK2) that phosphorylates the nicotinamide riboside precursor is increased, to a higher level in the DCM (40-fold) than in transverse aorta constriction (4-fold). This shift was also observed in human failing heart biopsies in comparison with nonfailing controls. We show that the Nmrk2 gene is an AMP-activated protein kinase and peroxisome proliferator-activated receptor α responsive gene that is activated by energy stress and NAD+ depletion in isolated rat cardiomyocytes. Nicotinamide riboside efficiently rescues NAD+ synthesis in response to FK866-mediated inhibition of nicotinamide phosphoribosyltransferase and stimulates glycolysis in cardiomyocytes. Accordingly, we show that nicotinamide riboside supplementation in food attenuates the development of heart failure in mice, more robustly in DCM, and partially after transverse aorta constriction, by stabilizing myocardial NAD+ levels in the failing heart. Nicotinamide riboside treatment also robustly increases the myocardial levels of 3 metabolites, nicotinic acid adenine dinucleotide, methylnicotinamide, and N1-methyl-4-pyridone-5-carboxamide, that can be used as validation biomarkers for the treatment.Conclusions: The data show that nicotinamide riboside, the most energy-efficient among NAD precursors, could be useful for treatment of heart failure, notably in the context of DCM, a disease with few therapeutic options