Articles de revues : « Famille M1 »

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Aslan, Nuray, Levi Watkin, Jonila Pishtari, Huiqing Xu, John L. Sullivan et Katherine Luzuriaga. « Expansion of influenza M1-specific memory cells cross-reactive with Epstein-Barr Virus (EBV) lytic epitopes correlates with severity of EBV-induced infectious mononucleosis (130.14) ». Journal of Immunology 182, n^o 1_Supplement (1 avril 2009) : 130.14. http://dx.doi.org/10.4049/jimmunol.182.supp.130.14.

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Abstract Cross-reactive memory T cells specific to previously encountered influenza A contribute to the lymphoproliferation characteristics of EBV-associated infectious mononucleosis (IM). We showed that cross-reactive CD8 T cell responses commonly occur during EBV infection. Strong cross-reactive T cell responses specific to influenza M1 (Flu-M1) and EBV-specific lytic epitope EBV-BRLF-1 have been observed in 10/10 HLA-A2+ IM patients. We also detected cross-reactive T cell responses that recognized both Flu-M1 and lytic EBV-BMLF-1 epitopes in 14/26 HLA-A2+ IM patients. In addition, 8/19 IM patients demonstrated some intra-viral cross-reactivity between EBV BRLF-1 and BMLF-1 specific epitopes. Cross-reactive T cell responses between Flu-M1 and EBV-BRLF-1/EBV-BMLF-1 epitopes were observed in all IM patients but at different time points after infection. Our analyses showed that Flu-M1 and EBV-BMLF-1 used few Vbeta TCR families that were stable overtime. However, EBV-BRLF-1-specific Vbeta TCR repertoire used multiple Vbeta families that varied between individuals and varied during the time course of IM in the same patient. Disease severity of IM directly correlated with percentage of Flu-M1-specific CD8 T cells but did not correlate with EBV-BMLF-1 or BRLF-1-specific responses.

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Paul, Kathleen, Christopher Stojanowski, Toby Hughes, Alan Brook et Grant Townsend. « Genetic Correlation, Pleiotropy, and Molar Morphology in a Longitudinal Sample of Australian Twins and Families ». Genes 13, n^o 6 (2 juin 2022) : 996. http://dx.doi.org/10.3390/genes13060996.

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This study aims to expand our understanding of the genetic architecture of crown morphology in the human diphyodont dentition. Here, we present bivariate genetic correlation estimates for deciduous and permanent molar traits and evaluate the patterns of pleiotropy within (e.g., m1–m2) and between (e.g., m2–M1) dentitions. Morphology was observed and scored from dental models representing participants of an Australian twin and family study (deciduous n = 290, permanent n = 339). Data collection followed Arizona State University Dental Anthropology System standards. Genetic correlation estimates were generated using maximum likelihood variance components analysis in SOLAR v.8.1.1. Approximately 23% of deciduous variance components models and 30% of permanent variance components models yielded significant genetic correlation estimates. By comparison, over half (56%) of deciduous–permanent homologues (e.g., m2 hypocone–M1 hypocone) were significantly genetically correlated. It is generally assumed that the deciduous and permanent molars represent members of a meristic molar field emerging from the primary dental lamina. However, stronger genetic integration among m2–M1/M2 homologues than among paired deciduous traits suggests the m2 represents the anterior-most member of a “true” molar field. The results indicate genetic factors act at distinct points throughout development to generate homologous molar form, starting with the m2, which is later replaced by a permanent premolariform crown.

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BERGMAN, GEORGE M. « ON COMMON DIVISORS OF MULTINOMIAL COEFFICIENTS ». Bulletin of the Australian Mathematical Society 83, n^o 1 (13 octobre 2010) : 138–57. http://dx.doi.org/10.1017/s0004972710001723.

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AbstractErdős and Szekeres [‘Some number theoretic problems on binomial coefficients’, Aust. Math. Soc. Gaz.5 (1978), 97–99] showed that for any four positive integers satisfying m1+m2=n1+n2, the two binomial coefficients (m1+m2)!/m1!m2! and (n1+n2)!/n1!n2! have a common divisor greater than 1. The analogous statement for k-element families of k-nomial coefficients (k>1) was conjectured in 1997 by David Wasserman.Erdős and Szekeres remark that if m1,m2,n1,n2 as above are all greater than 1, there is probably a lower bound on the common divisor in question which goes to infinity as a function of m1 +m2 . Such a bound is obtained in Section 2.The remainder of this paper is devoted to proving results that narrow the class of possible counterexamples to Wasserman’s conjecture.

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Salomon, Emmanuel, Marjorie Schmitt, Anil Marapaka, Athanasios Stamogiannos, Germain Revelant, Céline Schmitt, Sarah Alavi et al. « Aminobenzosuberone Scaffold as a Modular Chemical Tool for the Inhibition of Therapeutically Relevant M1 Aminopeptidases ». Molecules 23, n^o 10 (11 octobre 2018) : 2607. http://dx.doi.org/10.3390/molecules23102607.

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The synthesis of racemic substituted 7-amino-5,7,8,9-tetrahydrobenzocyclohepten-6-one hydrochlorides was optimized to enhance reproducibility and increase the overall yield. In order to investigate their specificity, series of enzyme inhibition assays were carried out against a diversity of proteases, covering representative members of aspartic, cysteine, metallo and serine endopeptidases and including eight members of the monometallic M1 family of aminopeptidases as well as two members of the bimetallic M17 and M28 aminopeptidase families. This aminobenzosuberone scaffold indeed demonstrated selective inhibition of M1 aminopeptidases to the exclusion of other tested protease families; it was particularly potent against mammalian APN and its bacterial/parasitic orthologues EcPepN and PfAM1.

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Pascual Alonso, Isel, Fabiola Almeida García, Mario Ernesto Valdés Tresanco, Yarini Arrebola Sánchez, Daniel Ojeda del Sol, Belinda Sánchez Ramírez, Isabelle Florent, Marjorie Schmitt et Francesc Xavier Avilés. « Marine Invertebrates : A Promissory Still Unexplored Source of Inhibitors of Biomedically Relevant Metallo Aminopeptidases Belonging to the M1 and M17 Families ». Marine Drugs 21, n^o 5 (28 avril 2023) : 279. http://dx.doi.org/10.3390/md21050279.

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Proteolytic enzymes, also known as peptidases, are critical in all living organisms. Peptidases control the cleavage, activation, turnover, and synthesis of proteins and regulate many biochemical and physiological processes. They are also involved in several pathophysiological processes. Among peptidases, aminopeptidases catalyze the cleavage of the N-terminal amino acids of proteins or peptide substrates. They are distributed in many phyla and play critical roles in physiology and pathophysiology. Many of them are metallopeptidases belonging to the M1 and M17 families, among others. Some, such as M1 aminopeptidases N and A, thyrotropin-releasing hormone-degrading ectoenzyme, and M17 leucyl aminopeptidase, are targets for the development of therapeutic agents for human diseases, including cancer, hypertension, central nervous system disorders, inflammation, immune system disorders, skin pathologies, and infectious diseases, such as malaria. The relevance of aminopeptidases has driven the search and identification of potent and selective inhibitors as major tools to control proteolysis with an impact in biochemistry, biotechnology, and biomedicine. The present contribution focuses on marine invertebrate biodiversity as an important and promising source of inhibitors of metalloaminopeptidases from M1 and M17 families, with foreseen biomedical applications in human diseases. The results reviewed in the present contribution support and encourage further studies with inhibitors isolated from marine invertebrates in different biomedical models associated with the activity of these families of exopeptidases.

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McClain, Mark S., Ping Cao, Hideki Iwamoto, Arlene D. Vinion-Dubiel, Gabor Szabo, Zhifeng Shao et Timothy L. Cover. « A 12-Amino-Acid Segment, Present in Type s2 but Not Type s1 Helicobacter pylori VacA Proteins, Abolishes Cytotoxin Activity and Alters Membrane Channel Formation ». Journal of Bacteriology 183, n^o 22 (15 novembre 2001) : 6499–508. http://dx.doi.org/10.1128/jb.183.22.6499-6508.2001.

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ABSTRACT Helicobacter pylori, a gram-negative bacterium associated with gastritis, peptic ulceration, and gastric adenocarcinoma in humans, secretes a protein toxin, VacA, that causes vacuolar degeneration of epithelial cells. Several different families of H. pylori vacA alleles can be distinguished based on sequence diversity in the “middle” region (i.e., m1 and m2) and in the 5′ end of the gene (i.e., s1 and s2). Type s2 VacA toxins contain a 12-amino-acid amino-terminal hydrophilic segment, which is absent from type s1 toxins. To examine the functional properties of VacA toxins containing this 12-amino-acid segment, we analyzed a wild-type s1/m1 VacA and a chimeric s2/m1 VacA protein. Purified s1/m1 VacA from H. pylori strain 60190 induced vacuolation in HeLa and Vero cells, whereas the chimeric s2/m1 toxin (in which the s1 sequence of VacA from strain 60190 was replaced with the s2 sequence from strain Tx30a) lacked detectable cytotoxic activity. Type s1/m1 VacA from strain 60190 formed membrane channels in a planar lipid bilayer assay at a significantly higher rate than did s2/m1 VacA. However, membrane channels formed by type s1 VacA and type s2 VacA proteins exhibited similar anion selectivities (permeability ratio, PCl/PNa = 5). When an equimolar mixture of the chimeric s2/m1 toxin and the wild-type s1/m1 toxin was added to HeLa cells, the chimeric toxin completely inhibited the activity of the s1/m1 toxin. Thus, the s2/m1 toxin exhibited a dominant-negative phenotype similar to that of a previously described mutant toxin, VacA-(Δ6–27). Immunoprecipitation experiments indicated that both s2/m1 VacA and VacA-(Δ6–27) could physically interact with a c-myc epitope-tagged s1/m1 VacA, which suggests that the dominant-negative phenotype results from the formation of heterooligomeric VacA complexes with defective functional activity. Despite detectable differences in the channel-forming activities and cytotoxic properties of type s1 and type s2 VacA proteins, the conservation of type s2 sequences in many H. pyloriisolates suggests that type s2 VacA proteins retain an important biological activity.

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Vasko, V. O., et V. V. Kyrychenko. « Induced Mutagenesis for the Creation of New Starting Material in Sunflower Breeding ». Helia 42, n^o 70 (26 juillet 2019) : 17–36. http://dx.doi.org/10.1515/helia-2017-0024.

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AbstractThe article colligates data of studies on the variability of quantitative and qualitative traits in mutant sunflower M1-M3 generations affected by dimethyl sulfate (DMS) (0.01, 0.05 %) and gamma rays (120; 150 Gy), frequencies and range of mutations in M2 and their inheritance in mutant families, chromosome aberrations in meiosis, as well as on the breeding and genetic value of induced mutants and possibilities of their use in breeding. The methodical peculiarities of the mutational breeding of the cross-pollinating crop were defined, and new mutants with changed features were created.Investigating new homozygous self-pollinated sunflower lines, we observed a more negative mutagenic impact of gamma irradiation (120 and 150 Gy) on the germinability of M1 sunflower seeds in the field compared with the DMS effect (0.01 and 0.05 %). The field germinability of DMS-treated seeds was 83–87 % vs. 11–15 % of gamma-irradiated ones.The mutagenic effect of gamma rays (120 and 150 Gy) on M1 meiosis was shown to be stronger than that of DMS (0.01 and 0.05 %). The percentage of cells with alterations varied within 15.79–18.78 % (120 Gy) and 20.38–25.26 % (150 Gy) compared to 0–0.16 % in the control.The effect of gamma rays on the frequency of morphoses in M1 was stronger, in particular, after exposure to 120 Gy or 150 Gy of gamma irradiation, the number of plants with alterations was 43 %, whereas after DMS treatment (0.01 and 0.05 %) this parameter averaged 27–28 %.We determined the inheritance of mutations of quantitative and qualitative traits, which are important for breeding, in mutant M2 families and selected mutant families with inherited altered traits that can be considered as mutations. Among the best mutations, there are morphological mutants with marker traits, mutants with increased content of oil in seeds, increased 1000-seed weight, increased contents of behenic, linoleic and palmitoleic acids as well as with absolute resistance to downy mildew.

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Pascual Alonso, Isel, Laura Rivera Méndez, Mario E. Valdés-Tresanco, Lotfi Bounaadja, Marjorie Schmitt, Yarini Arrebola Sánchez, Luis Alvarez Lajonchere, Jean-Louis Charli et Isabelle Florent. « Biochemical evidences for M1-, M17- and M18-like aminopeptidases in marine invertebrates from Cuban coastline ». Zeitschrift für Naturforschung C 75, n^o 11-12 (26 novembre 2020) : 397–407. http://dx.doi.org/10.1515/znc-2019-0169.

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AbstractMetallo-aminopeptidases (mAPs) control many physiological processes. They are classified in different families according to structural similarities. Neutral mAPs catalyze the cleavage of neutral amino acids from the N-terminus of proteins or peptide substrates; they need one or two metallic cofactors in their active site. Information about marine invertebrate’s neutral mAPs properties is scarce; available data are mainly derived from genomics and cDNA studies. The goal of this work was to characterize the biochemical properties of the neutral APs activities in eight Cuban marine invertebrate species from the Phyla Mollusca, Porifera, Echinodermata, and Cnidaria. Determination of substrate specificity, optimal pH and effects of inhibitors (1,10-phenanthroline, amastatin, and bestatin) and cobalt on activity led to the identification of distinct neutral AP-like activities, whose biochemical behaviors were similar to those of the M1 and M17 families of mAPs. Additionally, M18-like glutamyl AP activities were detected. Thus, marine invertebrates express biochemical activities likely belonging to various families of metallo-aminopeptidases.

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Strobel, Sonja, Stefan Bereswill, Peter Balig, Peter Allgaier, Hans-Günther Sonntag et Manfred Kist. « Identification and Analysis of a NewvacA Genotype Variant of Helicobacter pylori in Different Patient Groups in Germany ». Journal of Clinical Microbiology 36, n^o 5 (1998) : 1285–89. http://dx.doi.org/10.1128/jcm.36.5.1285-1289.1998.

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The vacuolating cytotoxin of Helicobacter pylori (VacA) is known to cause cell damage to mammalian cells and is suspected to give rise to gastric epithelial lesions that might lead to peptic ulcer disease. As shown recently, the gene encoding VacA exhibits genetic variation, with three different families of signal sequences (s1a, s1b, and s2) and two families of midregion sequences (m1 and m2). In order to investigate the relationship between the presence of specificvacA genotypes and peptic ulceration, the vacAgenotypes of 158 clinical isolates of H. pylori were determined. The study group consisted of 106 patients with duodenal ulceration; 52 patients with nonulcer dyspepsia (NUD) were used as controls. H. pylori of genotype s1 was isolated from 96% of the patients with ulcerations, whereas genotype s2 was only present in 4%, indicating a strong correlation between thevacA genotype and peptic ulceration (P < 0.001). In contrast, 31% of the patients from the NUD control group were infected with strains of vacA genotype s2. Particular midregion genotypes (m1 and m2) were not associated with clinical manifestations. The midregions from 18% of the isolates could not be classified by the proposed scheme. DNA sequencing revealed high homology between the untypeable midregions and that of genotype m1, with multiple base pair exchanges, some affecting the primer annealing site. Compared to those of m1 and m2 alleles, the divergent midregions from untypeable strains showed clustering, indicating the presence of a further subfamily of sequences in the midregion of vacA in German isolates, for which we propose the term “m1a.” A new specific primer that we designed for typing m1a isolates might be useful in other studies.

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Perez-Perez, Guillermo I., Richard M. Peek, John C. Atherton, Martin J. Blaser et Timothy L. Cover. « Detection of Anti-VacA Antibody Responses in Serum and Gastric Juice Samples Using Type s1/m1 and s2/m2 Helicobacter pylori VacA Antigens ». Clinical Diagnostic Laboratory Immunology 6, n^o 4 (1 juillet 1999) : 489–93. http://dx.doi.org/10.1128/cdli.6.4.489-493.1999.

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ABSTRACT Several different families of vacuolating toxin (vacA) alleles are present in Helicobacter pylori, and they encode products with differing functional activities. H. pyloristrains containing certain types of vacA alleles have been associated with an increased risk for peptic ulcer disease. In this study, we tested serum samples and gastric juice from 19 H. pylori-negative and 39 H. pylori-positive patients for enzyme-linked immunosorbent assay reactivity with two different types of VacA antigens (types s1/m1 and s2/m2), which were purified from H. pylori 60190 and 86-338, respectively. Both antigens were recognized better by serum immunoglobulin G (IgG) fromH. pylori-positive persons than by serum IgG from H. pylori-negative persons (P < 0.01). The s1/m1 VacA antigen was better recognized by sera from patients carryingvacA type s1/m1 strains than by sera from patients carryingvacA type s2/m2 or s1/m2 strains (P < 0.01). Conversely, the s2/m2 VacA antigen was better recognized by sera from patients carrying type s2/m2 or s1/m2 strains (P= 0.03). Serum IgG anti-VacA antibodies were present more frequently in patients carrying type s1/m1 strains than in other H. pylori-positive patients (P = 0.0002). In addition, the highest levels of IgA anti-VacA antibodies were detected in the gastric juice of patients carrying type s1/m1 strains. These data indicate that different VacA isoforms have distinct antigenic properties and that multiple forms of VacA elicit antibody responses inH. pylori-positive humans.

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Carroll, W. D., W. Lenney, P. W. Jones, R. C. Strange, F. Child, M. K. Whyte, R. A. Primhak et A. A. Fryer. « Effects of glutathione S-transferase M1, T1 and P1 on lung function in asthmatic families ». Clinical Experimental Allergy 35, n^o 9 (septembre 2005) : 1155–61. http://dx.doi.org/10.1111/j.1365-2222.2005.02313.x.

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Cunningham, Eithne, Marcin Drag, Pawel Kafarski et Angus Bell. « Chemical Target Validation Studies of Aminopeptidase in Malaria Parasites Using α-Aminoalkylphosphonate and Phosphonopeptide Inhibitors ». Antimicrobial Agents and Chemotherapy 52, n^o 9 (5 mai 2008) : 3221–28. http://dx.doi.org/10.1128/aac.01327-07.

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ABSTRACT During its intraerythrocytic phase, the most lethal human malarial parasite, Plasmodium falciparum, digests host cell hemoglobin as a source of some of the amino acids required for its own protein synthesis. A number of parasite endopeptidases (including plasmepsins and falcipains) process the globin into small peptides. These peptides appear to be further digested to free amino acids by aminopeptidases, enzymes that catalyze the sequential cleavage of N-terminal amino acids from peptides. Aminopeptidases are classified into different evolutionary families according to their sequence motifs and preferred substrates. The aminopeptidase inhibitor bestatin can disrupt parasite development, suggesting that this group of enzymes might be a chemotherapeutic target. Two bestatin-susceptible aminopeptidase activities, associated with gene products belonging to the M1 and M17 families, have been described in blood-stage P. falciparum parasites, but it is not known whether one or both are required for parasite development. To establish whether inhibition of the M17 aminopeptidase is sufficient to confer antimalarial activity, we evaluated 35 aminoalkylphosphonate and phosphonopeptide compounds designed to be specific inhibitors of M17 aminopeptidases. The compounds had a range of activities against cultured P. falciparum parasites with 50% inhibitory concentrations down to 14 μM. Some of the compounds were also potent inhibitors of parasite aminopeptidase activity, though it appeared that many were capable of inhibiting the M1 as well as the M17 enzyme. There was a strong correlation between the potencies of the compounds against whole parasites and against the enzyme, suggesting that M17 and/or M1 aminopeptidases may be valid antimalarial drug targets.

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Newell, Chris, Digby J. Growns et Jen A. McComb. « A novel in vitro rooting method employing an aerobic medium ». Australian Journal of Botany 53, n^o 1 (2005) : 81. http://dx.doi.org/10.1071/bt04061.

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The beneficial influence of an aerobic propagation medium for in vitro cultures during the rooting phase was found for 28 Australian species and genotypes from the families Liliaceae, Haemodoraceae, Myrtaceae, Thymelaeaceae, Proteaceae, Goodeniaceae and Rutaceae. Microcuttings from established shoot cultures were pulsed for 7 days in the dark on a high-auxin (40 µM indole-3-butyric acid, IBA), agar-solidified medium. The microcuttings were then transferred either to an agar-solidified medium without plant-growth regulators (M1) or a sterile propagation mix. The protocol utilising propagation mix used is referred to as IVS (in vitro soil-less medium). The pulsed cuttings in agar or IVS were placed in the culture room under standard light and temperature regimes and allowed to root. When compared over two harvest times, the use of IVS as a rooting medium gave consistent improvements over the use of M1 medium for percentage rooting, average total root length and root number per microcutting. In total, 27 of the 28 species tested rooted in IVS medium at equal or better rates than in M1. In three cases, Actinodium cunninghamii, one of the genotypes of Pimelea physodes and one of the genotypes of Eriostemon australasis shoots did not root in M1 but showed good root development in IVS medium. With few exceptions, average root length and root number in microcuttings rooted in IVS were superior to the lengths and numbers recorded in agar medium. The materials handing advantages and the application of IVS are discussed.

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Newell, Chris, Jen A. McComb et Digby J. Growns. « Corrigendum to : A novel in vitro rooting method employing an aerobic medium ». Australian Journal of Botany 53, n^o 3 (2005) : 281. http://dx.doi.org/10.1071/bt04061_co.

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The beneficial influence of an aerobic propagation medium for in vitro cultures during the rooting phase was found for 28 Australian species and genotypes from the families Liliaceae, Haemodoraceae, Myrtaceae, Thymelaeaceae, Proteaceae, Goodeniaceae and Rutaceae. Microcuttings from established shoot cultures were pulsed for 7 days in the dark on a high-auxin (40 µM indole-3-butyric acid, IBA), agar-solidified medium. The microcuttings were then transferred either to an agar-solidified medium without plant-growth regulators (M1) or a sterile propagation mix. The protocol utilising propagation mix used is referred to as IVS (in vitro soil-less medium). The pulsed cuttings in agar or IVS were placed in the culture room under standard light and temperature regimes and allowed to root. When compared over two harvest times, the use of IVS as a rooting medium gave consistent improvements over the use of M1 medium for percentage rooting, average total root length and root number per microcutting. In total, 27 of the 28 species tested rooted in IVS medium at equal or better rates than in M1. In three cases, Actinodium cunninghamii, one of the genotypes of Pimelea physodes and one of the genotypes of Eriostemon australasis shoots did not root in M1 but showed good root development in IVS medium. With few exceptions, average root length and root number in microcuttings rooted in IVS were superior to the lengths and numbers recorded in agar medium. The materials handing advantages and the application of IVS are discussed.

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Amorim, Dalton S., et Luiz Augusto Mazzarolo. « Cratomyia macrorrhyncha, a Lower Cretaceous brachyceran fossil from the Santana Formation, Brazil, representing a new species, genus and family of the Stratiomyomorpha (Diptera) ». Insect Systematics & ; Evolution 31, n^o 1 (2000) : 91–102. http://dx.doi.org/10.1163/187631200x00336.

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AbstractA new fossil Brachycera (Diptera), Cratomyia macrorrhyncha gen. n. & sp. n. is described from the Santana Formation, Lower Cretaceous, situated on the Araripe Basin (Northeastern Brazil). Its remarkable features are the large body size, very long proboscis, antenna with multi-articled flagellum, robust thorax and abdomen, and wing characters like the abbreviated costal vein, distally forked veins R4+5 and M1+2, strongly arched M1, and closed cells m3 and cup. The new genus and species does not reasonably fit in any of the existing families and a new family, Cratomyiidae is proposed. The systematic position of the family is discussed. Reasons are given for not including it in the following higher taxa of Brachycera: Xylophagomorpha, Tabanomorpha, Vermileonomorpha, Asilomorpha, and Eremoneura. The Cratomyiidae are included in Stratiomyomorpha as the sister-group of Xylomyidae + Stratiomyidae, above the origin of Pantophthalmidae.

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Al-Safadi, Bassam, et Philipp W. Simon. « Gamma Irradiation-induced Variation in Carrots (Daucus carota L.) ». Journal of the American Society for Horticultural Science 121, n^o 4 (juillet 1996) : 599–603. http://dx.doi.org/10.21273/jashs.121.4.599.

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Carrot tissue cultures, germinating seed, and dry seed were exposed to gamma radiation. Irradiation accelerated germination of carrot seed in the M1 generation at low doses (0.5 and 1 krad), whereas higher doses delayed germination. A high negative correlation was observed between dose and survival of plants after seed irradiation. Plant size and root weight were 20 % to 35% greater than control plants after seeds, but not tissue cultures, were exposed to low doses of gamma irradiation. Higher doses reduced M1 plant size by >50% in germinating seed and tissue culture treatments but less for the dry seed treatment. Seed production decreased while phenotypic variation of M1 plants increased with increasing gamma ray dosage. Root weight and total dissolved solids were highly variable in M2 families. Less variation was observed in total carotene content and none was seen in sugar type (reducing vs. nonreducing sugars). Induced variation in root color and root shape was also observed. Irradiation of germinating seed and tissue cultures yielded more M2 variation than irradiation of dry seed. Putative point mutations were not observed. Unirradiated carrot tissue cultures did not yield significant M2 somaclonal variation. Average root weight of M2 plants increased with increasing gamma ray dosage, especially for the dry seed treatment.

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Carruba, V., S. Aljbaae, R. C. Domingos et W. Barletta. « Artificial neural network classification of asteroids in the M1:2 mean-motion resonance with Mars ». Monthly Notices of the Royal Astronomical Society 504, n^o 1 (7 avril 2021) : 692–700. http://dx.doi.org/10.1093/mnras/stab914.

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ABSTRACT Artificial neural networks (ANNs) have been successfully used in the last years to identify patterns in astronomical images. The use of ANN in the field of asteroid dynamics has been, however, so far somewhat limited. In this work, we used for the first time ANN for the purpose of automatically identifying the behaviour of asteroid orbits affected by the M1:2 mean-motion resonance with Mars. Our model was able to perform well above 85 per cent levels for identifying images of asteroid resonant arguments in term of standard metrics like accuracy, precision, and recall, allowing to identify the orbital type of all numbered asteroids in the region. Using supervised machine learning methods, optimized through the use of genetic algorithms, we also predicted the orbital status of all multi-opposition asteroids in the area. We confirm that the M1:2 resonance mainly affects the orbits of the Massalia, Nysa, and Vesta asteroid families.

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Ahlberg, Sara, Delia Grace, Gideon Kiarie, Yumi Kirino et Johanna Lindahl. « A Risk Assessment of Aflatoxin M1 Exposure in Low and Mid-Income Dairy Consumers in Kenya ». Toxins 10, n^o 9 (29 août 2018) : 348. http://dx.doi.org/10.3390/toxins10090348.

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Aflatoxin M1 (AFM1), a human carcinogen, is found in milk products and may have potentially severe health impacts on milk consumers. We assessed the risk of cancer and stunting as a result of AFM1 consumption in Nairobi, Kenya, using worst case assumptions of toxicity and data from previous studies. Almost all (99.5%) milk was contaminated with AFM1. Cancer risk caused by AFM1 was lower among consumers purchasing from formal markets (0.003 cases per 100,000) than for low-income consumers (0.006 cases per 100,000) purchasing from informal markets. Overall cancer risk (0.004 cases per 100,000) from AFM1 alone was low. Stunting is multifactorial, but assuming only AFM1 consumption was the determinant, consumption of milk contaminated with AFM1 levels found in this study could contribute to 2.1% of children below three years in middle-income families, and 2.4% in low-income families, being stunted. Overall, 2.7% of children could hypothetically be stunted due to AFM1 exposure from milk. Based on our results AFM1 levels found in milk could contribute to an average of −0.340 height for age z-score reduction in growth. The exposure to AFM1 from milk is 46 ng/day on average, but children bear higher exposure of 3.5 ng/kg bodyweight (bw)/day compared to adults, at 0.8 ng/kg bw/day. Our paper shows that concern over aflatoxins in milk in Nairobi is disproportionate if only risk of cancer is considered, but that the effect on stunting children might be much more significant from a public health perspective; however, there is still insufficient data on the health effects of AFM1.

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Kukuljan, M., P. Labarca et R. Latorre. « Molecular determinants of ion conduction and inactivation in K+ channels ». American Journal of Physiology-Cell Physiology 268, n^o 3 (1 mars 1995) : C535—C556. http://dx.doi.org/10.1152/ajpcell.1995.268.3.c535.

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K+ channel-forming proteins can be grouped into three families that differ by the number of potential membrane-spanning segments. The largest of these families is composed of tetrameric channels with subunits containing six putative membrane-spanning segments (S1-S6). Inward rectifiers comprise a second family of K+ channels with subunits having two transmembrane domains (M1, M2). Monomers in the third family are proteins containing only one membrane-spanning segment, and they give origin to minK+ channels. Joining together segments S5 and S6 in the case of voltage-gated K+ channels and M1 and M2 in inward rectifiers, there is a highly conserved region with a hairpin shape called the H5 or P region. The P region, the loop connecting the S4 and S5 domains and the S6 transmembrane segment in Shaker-type K+ channels and the COOH-terminal in inward rectifiers, appears to play crucial roles in ion conduction. In Shaker K+ channels the NH2-terminal has been identified as responsible for fast inactivation (N-type inactivation). If the fast-inactivation gate is removed, a slower inactivation process persists, and its rate can be altered by mutations of amino acid residues forming part of the region in the neighborhood of the COOH-terminal (C-type inactivation). In this review we discuss the strategies followed to identify the different structures of K+ channels involved in ion conduction and inactivation processes and how they interplay.

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Iglesias Bonilla, P., E. Mayoral Sánchez, J. Lapetra Peralta, M. Iborra Oquendo, F. Villalba Alcalá et A. Cayuela Domínguez. « Validación de dos sistemas de automedida de presión arterial, modelos OMRON HEM-705 CP y OMRON M1 (HEM 422C2-E) ». Atención Primaria 30, n^o 1 (2002) : 22–28. http://dx.doi.org/10.1016/s0212-6567(02)78959-2.

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Maev, Igor V., Dmitry N. Andreev, Andrew V. Zaborovsky et Elena G. Lobanova. « Current status and prospects of using the prokinetic acotiamide in gastroenterology : A review ». Terapevticheskii arkhiv 95, n^o 8 (11 octobre 2023) : 716–21. http://dx.doi.org/10.26442/00403660.2023.08.202396.

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Acotiamide is a prokinetic with a novel mechanism of action an antagonist of muscarinic M1 and M2 receptors and an acetylcholinesterase inhibitor. Acetylcholine is the central mediator of the tone of the muscular components of the gastrointestinal tract, increasing its motor activity. Blockade of presynaptic M1 and M2 receptors neutralizes the inhibitory effect of the feedback mechanism on the acetylcholine synthesis, while inhibition of acetylcholinesterase in the synaptic cleft reduces the acetylcholine degradation. Currently, the clinical efficacy of acotiamide in the population of patients with functional dyspepsia is demonstrated in more than 10 clinical studies in different regions of the world, demonstrating a reduction of the symptoms of the disease during treatment with this agent and an improvement in the quality of life of patients. In addition, the combination of acotiamide with proton pump inhibitors optimizes the management of patients with gastroesophageal reflux disease.

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Jaffal, Lama, Wissam Joumaa, Alexandre Assi, Charles Helou, Christel Condroyer, Maya El Dor, Georges Cherfan et al. « Novel Missense Mutations in BEST1 Are Associated with Bestrophinopathies in Lebanese Patients ». Genes 10, n^o 2 (18 février 2019) : 151. http://dx.doi.org/10.3390/genes10020151.

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To identify Bestrophin 1 (BEST1) causative mutations in six Lebanese patients from three families, of whom four had a presumed clinical diagnosis of autosomal recessive bestrophinopathy (ARB) and two showed a phenotype with a single vitelliform lesion, patients were subjected to standard ophthalmic examinations. In addition, BEST1 exons and their flanking regions were amplified and sequenced by Sanger sequencing. Co-segregation and detailed bio-informatic analyses were performed. Clinical examination results were consistent with ARB diagnosis for all index patients showing multifocal vitelliform lesions and a markedly reduced light peak in the electrooculogram, including the two patients with a single vitelliform lesion. In all cases, most likely disease-causing BEST1 mutations co-segregated with the phenotype. The ARB cases showed homozygous missense variants (M1, c.209A>G, p.(Asp70Gly) in exon 3, M2, c.1403C>T; p.(Pro468Leu) in exon 10 and M3, c.830C>T, p.(Thr277Met) in exon 7), while the two patients with a single vitelliform lesion were compound heterozygous for M1 and M2. To our knowledge, this is the first study describing mutations in Lebanese patients with bestrophinopathy, where novel biallelic BEST1 mutations associated with two phenotypes were identified. Homozygous mutations were associated with multifocal lesions, subretinal fluid, and intraretinal cysts, whereas compound heterozygous ones were responsible for a single macular vitelliform lesion.

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Loconto, Jennifer, Fabio Papes, Ernie Chang, Lisa Stowers, Elsy P. Jones, Toyoyuki Takada, Attila Kumánovics, Kirsten Fischer Lindahl et Catherine Dulac. « Functional Expression of Murine V2R Pheromone Receptors Involves Selective Association with the M10 and M1 Families of MHC Class Ib Molecules ». Cell 112, n^o 5 (mars 2003) : 607–18. http://dx.doi.org/10.1016/s0092-8674(03)00153-3.

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Cao, Guangtian, Tingting Song, Yingyue Shen, Qunli Jin, Weilin Feng, Lijun Fan et Weiming Cai. « Diversity of Bacterial and Fungal Communities in Wheat Straw Compost for Agaricus bisporus Cultivation ». HortScience 54, n^o 1 (janvier 2019) : 100–109. http://dx.doi.org/10.21273/hortsci13598-18.

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The Agaricus genus represents the most popular edible mushroom in the world. Wheat straw often is used as the substrate for mushroom cultivation following pretreatment to degrade the lignocellulosic biomass in agricultural waste. In this study, we investigated the changes in bacterial and fungal microflora of wheat straw substrate during different phases of composting. We collected samples of the raw material (M1), phase I aerobic fermentation (F1, F2, F3), and phase II after-fermentation (AF1) for high-throughput 16S rRNA and internal transcribed spacer (ITS) sequencing to analyze the microbial diversity in the substrate during composting. Our data revealed that among the five stages, 365 operational taxonomic units (OTUs) were shared, with Firmicutes, Proteobacteria, and Actinobacteria being the predominant bacterial phyla. In addition, Thermobispora, Thermopolyspora, Ruminiclostridium, Thermobacillus, and Bacillus were the predominant genera in F3 and AF1, with the species Thermobispora bispora and Pseudoxanthomonas taiwanensis being predominant in F2. Both principal component analysis (PCA) and nonmetric multidimensional scaling (NMDS) plots showed that the bacterial communities of five stages could be distinguished from each other based on their composting time. The Shannon and Simpson indexes of F2 were lower than M1 (P < 0.05), and the clustering dendrogram showed that the bacterial communities in AF1 were similar to F3, with Micromonosporaceae, Streptosporaceae, Thermomonosporaceae, and Vulgatibacteraceae representing the differential bacterial families by linear discriminant analysis with effect size (LEfSe) analysis. The analysis of fungal communities showed that 384 OTUs were common among the five stages, with 1054 and 454 OTUs unique to M1 and AF1, respectively. Ascomycota and Basidiomycota were the two predominant phyla in all stages, and Chytridiomycota was predominant in F2, F3, and AF1 stages. PCA and NMDS plots showed that the clusters of F2 and AF1 were more dispersed than the other stages. No differences were observed in alpha diversity between the stages, and samples of F1, F2, and F3 were closer to AF1 in the clustering dendrogram. By LEfSe analysis, Mycothermus thermophilus, Gonapodya polymorpha, and Phaeophleospora_eugeniae were identified as the predominant fungal species in AF1.

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Mohamadi, Ali, Marco Martari, Cindy D. Holladay, John A. Phillips, Primus E. Mullis et Roberto Salvatori. « Mutation Analysis of the Muscarinic Cholinergic Receptor Genes in Isolated Growth Hormone Deficiency Type IB ». Journal of Clinical Endocrinology & ; Metabolism 94, n^o 7 (1 juillet 2009) : 2565–70. http://dx.doi.org/10.1210/jc.2009-0512.

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Background: Isolated GH deficiency (IGHD) is familial in 5–30% of patients. The most frequent form (IGHD-IB) has autosomal recessive inheritance, and it is known that it can be caused by mutations in the GHRH receptor (GHRHR) gene or in the GH gene. However, most forms of IGHD-IB have an unknown genetic cause. In normal subjects, muscarinic cholinergic stimulation causes an increase in pituitary GH release, whereas its blockade has the opposite effect, suggesting that a muscarinic acetylcholine receptor (mAchR) is involved in stimulating GH secretion. Five types of mAchR (M1–M5) exist. A transgenic mouse in which the function of the M3 receptor was selectively ablated in the central nervous system has isolated GH deficiency similar to animals with defective GHRH or GHRHR gene. Objective: We hypothesized that mAchR mutations may cause a subset of familial IGHD. Patients/Methods: After confirming the expression of M1–M5 receptor mRNA in human hypothalamus, we analyzed the index cases of 39 families with IGHD-IB for mutations in the genes encoding for the five receptors. Coding sequences for each of the five mAchRs were subjected to direct sequencing. Results: In one family, an affected member was homozygous for a M3 change in codon 65 that replaces valine with isoleucine (V65I). The V65I receptor was expressed in CHO cells where it had normal ability to transmit methacholine signaling. Conclusion: mAchR mutations are absent or rare (less than 2.6%) in familial IGHD type IB.

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Hudig, Dorothy, Keli Tokunaga, Alexander P. Sung, Michael J. Guglielmo, Julie Smith-Gagen, Rebecca Merica et Doug Redelman. « Monocytes of Chronic Fatigue Syndrome Patients, their Family Members without CFS, and Unrelated Healthy Donors : Searching for Differences ». Journal of Immunology 202, n^o 1_Supplement (1 mai 2019) : 182.50. http://dx.doi.org/10.4049/jimmunol.202.supp.182.50.

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Abstract Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is characterized by fatigue that does not improve with rest and worsens with exertion. ME/CFS may involve inflammation in the brain and/or be associated with viral infections. Increased numbers of pro-inflammatory monocytes in blood are a hallmark of infection. Biomarkers for, and information about, the CFS disease process are greatly needed. Here we queried circulating monocytes. In a pilot study, CFS patients and family members without CFS from three families were compared in order to reduce genetic and environmental variables. The patients conformed to the Fukuda 1994 standards. Unrelated healthy control subjects matched to the patients were included in the study. Blood monocytes were stained and analyzed by flow cytometry: counted with TruCountR beads, or stained after isolation and overnight culture of isolated peripheral blood monocytes. M1 pro-inflammatory monocytes are CD16A negative, while anti-inflammatory monocytes are CD16A positive; CD2 is a marker for dendritic monocytes, and changes in forward scatter could indicate in vitro activation. Notably, there were statistically significant differences between the lower percentages of M1 monocytes of the CFS patients compared to the controls; however, these differences were not significant between the patients and their family members without CFS. Also, the CD16A MFIs of the patients' monocytes were lower compared to controls but not to family members. One conclusion is that it is important to include family members without CFS as a control group in the search for biomarkers to diagnose CFS.

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Jaffal, Lama, Wissam H. Joumaa, Alexandre Assi, Charles Helou, George Cherfan, Kazem Zibara, Isabelle Audo, Christina Zeitz et Said El Shamieh. « Next Generation Sequencing Identifies Five Novel Mutations in Lebanese Patients with Bardet–Biedl and Usher Syndromes ». Genes 10, n^o 12 (16 décembre 2019) : 1047. http://dx.doi.org/10.3390/genes10121047.

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Aim: To identify disease-causing mutations in four Lebanese families: three families with Bardet–Biedl and one family with Usher syndrome (BBS and USH respectively), using next generation sequencing (NGS). Methods: We applied targeted NGS in two families and whole exome sequencing (WES) in two other families. Pathogenicity of candidate mutations was evaluated according to frequency, conservation, in silico prediction tools, segregation with disease, and compatibility with inheritance pattern. The presence of pathogenic variants was confirmed via Sanger sequencing followed by segregation analysis. Results: Most likely disease-causing mutations were identified in all included patients. In BBS patients, we found (M1): c.2258A > T, p. (Glu753Val) in BBS9, (M2): c.68T > C; p. (Leu23Pro) in ARL6, (M3): c.265_266delTT; p. (Leu89Valfs*11) and (M4): c.880T > G; p. (Tyr294Asp) in BBS12. A previously known variant (M5): c.551A > G; p. (Asp184Ser) was also detected in BBS5. In the USH patient, we found (M6): c.188A > C, p. (Tyr63Ser) in CLRN1. M2, M3, M4, and M6 were novel. All of the candidate mutations were shown to be likely disease-causing through our bioinformatic analysis. They also segregated with the corresponding phenotype in available family members. Conclusion: This study expanded the mutational spectrum and showed the genetic diversity of BBS and USH. It also spotlighted the efficiency of NGS techniques in revealing mutations underlying clinically and genetically heterogeneous disorders.

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Hansen, Bradley M. S., et Smadar Naoz. « The stationary points of the hierarchical three-body problem ». Monthly Notices of the Royal Astronomical Society 499, n^o 2 (3 septembre 2020) : 1682–700. http://dx.doi.org/10.1093/mnras/staa2602.

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ABSTRACT We study the stationary points of the hierarchical three body problem in the planetary limit (m1, m2 ≪ m0) at both the quadrupole and octupole orders. We demonstrate that the extension to octupole order preserves the principal stationary points of the quadrupole solution in the limit of small outer eccentricity e2 but that new families of stable fixed points occur in both prograde and retrograde cases. The most important new equilibria are those that branch off from the quadrupolar solutions and extend to large e2. The apsidal alignment of these families is a function of mass and inner planet eccentricity, and is determined by the relative directions of precession of ω1 and ω2 at the quadrupole level. These new equilibria are also the most resilient to the destabilizing effects of relativistic precession. We find additional equilibria that enable libration of the inner planet argument of pericentre in the limit of radial orbits and recover the non-linear analogue of the Laplace–Lagrange solutions in the coplanar limit. Finally, we show that the chaotic diffusion and orbital flips identified with the eccentric Kozai–Lidov mechanism and its variants can be understood in terms of the stationary points discussed here.

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Wiśniewska, Anita, Agnieszka Chrapkowska, Agata Kot-Wasik, Jerzy Konopa et Zofia Mazerska. « Metabolic transformations of antitumor imidazoacridinone, C-1311, with microsomal fractions of rat and human liver. » Acta Biochimica Polonica 54, n^o 4 (17 décembre 2007) : 831–38. http://dx.doi.org/10.18388/abp.2007_3179.

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The imidazoacridinone derivative C-1311 is an antitumor agent in Phase II clinical trials. The molecular mechanism of enzymatic oxidation of this compound in a peroxidase model system was reported earlier. The present studies were performed to elucidate the role of rat and human liver enzymes in metabolic transformations of this drug. C-1311 was incubated with different fractions of liver cells and the reaction mixtures were analyzed by RP-HPLC. We showed that the drug was more sensitive to metabolism with microsomes than with cytosol or S9 fraction of rat liver cells. Incubation of C-1311 with microsomes revealed the presence of four metabolites. Their structures were identified as dealkylation product, M0, as well as a dimer-like molecule, M1. Furthermore, we speculate that the hydroxyl group was most likely substituted in metabolite M3. It is of note that a higher rate of transformation was observed for rat than for human microsomes. However, the differences in metabolite amounts were specific for each metabolite. The reactivity of C-1311 with rat microsomes overexpressing P450 isoenzymes, of CYP3A and CYP4A families was higher than that with CYP1A and CYP2B. Moreover, the M1 metabolite was selectively formed with CYP3A, whereas M3 with CYP4A. In conclusion, this study revealed that C-1311 varied in susceptibility to metabolic transformation in rat and human cells and showed selectivity in the metabolism with P450 isoenzymes. The obtained results could be useful for preparing the schedule of individual directed therapy with C-1311 in future patients.

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Voloshynovskiy, Slava, Olga Taran, Mouad Kondah, Taras Holotyak et Danilo Rezende. « Variational Information Bottleneck for Semi-Supervised Classification ». Entropy 22, n^o 9 (27 août 2020) : 943. http://dx.doi.org/10.3390/e22090943.

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In this paper, we consider an information bottleneck (IB) framework for semi-supervised classification with several families of priors on latent space representation. We apply a variational decomposition of mutual information terms of IB. Using this decomposition we perform an analysis of several regularizers and practically demonstrate an impact of different components of variational model on the classification accuracy. We propose a new formulation of semi-supervised IB with hand crafted and learnable priors and link it to the previous methods such as semi-supervised versions of VAE (M1 + M2), AAE, CatGAN, etc. We show that the resulting model allows better understand the role of various previously proposed regularizers in semi-supervised classification task in the light of IB framework. The proposed IB semi-supervised model with hand-crafted and learnable priors is experimentally validated on MNIST under different amount of labeled data.

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Hoepner, R., R. Gold et S. Faissner. « Mikroglia im Kontext der Multiplen Sklerose ». Nervenheilkunde 33, n^o 11 (2014) : 805–10. http://dx.doi.org/10.1055/s-0038-1627744.

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ZusammenfassungMikroglia sind die residenten Makrophagen des zentralen Nervensystems (ZNS). Sie haben einen wichtigen Anteil an der Aufrechterhaltung von Abwehrmechanismen des ZNS wie der Phagozytose von apoptotischen Zellen und Zelldetritus. Es gibt wachsende Evidenz, die Mikroglia einen Einfluss für die Pathogenese der Multiplen Sklerose (MS) zuschreibt, vor allem in den progredienten Phasen der Erkrankung. Der Einfluss von Mikroglia auf die Pathogenese der MS soll in diesem Übersichtsartikel beleuchtet werden.Es wurde eine PubMed Datenbankanalyse durchgeführt und relevante Artikel bezüglich der Thematik berücksichtigt.MS ist gekennzeichnet durch eine Schädigung der Myelinscheide mit konsekutiver Demyelinisierung und auch axonalem Schaden. Dies wird durch inflammatorische Vorgänge mit Beteiligung von Mikroglia durch Freisetzung tion, Glia reaktiver Sauerstoff- und Stickstoffmetabolite und proinflammatorischer Zytokine wie IL-1beta und TNF-alpha vermittelt. Mikroglia können unterschiedliche Aktivierungszustände einnehmen; den klassischen Aktivierungszustand mit einem inflammatorischen Zytokinmuster (M1) sowie den alternativen Aktivierungszustand (M2), in welchem ein neuroprotektives Zytokinmuster dominiert. Mittlerweile gibt es therapeutische Ansätze, die auf eine mikrogliale Modulation abzielen, z. B. der Nrf2-Signalweg, der durch Dimethylfumarat beeinflusst wird oder die Verringerung von reaktiven Sauerstoffmetaboliten durch Interferone.Die Bedeutung mikroglialer Aktivierung sowie die therapeutische Beeinflussung von Mikroglia mit dem Ziel der Neuroprotektion sind zuletzt immer mehr in den Fokus gerückt und sollen in diesem Übersichtsartikel genauer beleuchtet werden.

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Astorg, Matthieu, et Fabrizio Bianchi. « Higher bifurcations for polynomial skew products ». Journal of Modern Dynamics 18 (2022) : 69. http://dx.doi.org/10.3934/jmd.2022003.

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<p style='text-indent:20px;'>We continue our investigation of the parameter space of families of polynomial skew products. Assuming that the base polynomial has a Julia set not totally disconnected and is neither a Chebyshev nor a power map, we prove that, near any bifurcation parameter, one can find parameters where <inline-formula><tex-math id="M1">\begin{document}$ k $\end{document}</tex-math></inline-formula> critical points bifurcate <i>independently</i>, with <inline-formula><tex-math id="M2">\begin{document}$ k $\end{document}</tex-math></inline-formula> up to the dimension of the parameter space. This is a striking difference with respect to the one-dimensional case. The proof is based on a variant of the inclination lemma, applied to the postcritical set at a Misiurewicz parameter. By means of an analytical criterion for the non-vanishing of the self-intersections of the bifurcation current, we deduce the equality of the supports of the bifurcation current and the bifurcation measure for such families. Combined with results by Dujardin and Taflin, this also implies that the support of the bifurcation measure in these families has non-empty interior. As part of our proof we construct, in these families, subfamilies of codimension 1 where the bifurcation locus has non empty interior. This provides a new independent proof of the existence of holomorphic families of arbitrarily large dimension whose bifurcation locus has non empty interior. Finally, it shows that the Hausdorff dimension of the support of the bifurcation measure is maximal at any point of its support.</p>

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Xiong, Wu, Mei-xin Tan, Zi-lin Chen, Yu Liu, Yang Liu, Xiao-ling Zou, Xiao-qin Wang, Ya Yang, Pei Tan et Xi Zhang. « Endothelial progenitor cell (EPCs)-derived exosomal miR-30d-5p inhibits the inflammatory response of high glucose-impaired fibroblasts by affecting the M1/M2 polarization of macrophages ». Revista Romana de Medicina de Laborator 30, n^o 4 (1 octobre 2022) : 435–51. http://dx.doi.org/10.2478/rrlm-2022-0032.

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Abstract Background: Diabetes is a common chronic disease which has caused a great burden on families and society. The treatment of diabetes has always been a hotspot. This study aimed to explore the effect and mechanism of miR-30d-5pon inflammation of high glucose-impaired human keloid fibroblasts (HKF). Methods: Differently-expressed miRNAs were predicted by bioinformatics methods. Exosomes were observed by transmission electron microscope. Exosome particle sizes were measured by NanoSight. Western Blot was used to detect the expression of CD81, CD63, CD9, and Calnexin. QRT-PCR was used to detect the expression of miR-30d-5p, IL-1β, TNF-α, VEGF, FGF21, NRF2, and HO-1. The levels of IL-1β, TNF-α, IL-6, IL-10, and TGF-β were determined by ELISA. Cell apoptosis and CD86, CD206 positive cells were detected by flow cytometry. Results: Tori formula could promote the secretion of endothelial progenitor cell (EPCs) exosomes. EPCs exosomes and miR-30d-5p could stimulate the proliferation of HKF impaired by high glucose and the expression of IL-10 and TGF-β. MiR-30d-5p inhibited the proliferation of M1 macrophages and the expression of IL-1β and TNF-α. It could also promote the proliferation of M2 macrophages and the expression of CCL17 and CCL22. Moreover, miR-30d-5p stimulated the expression of VEGF, FGF21, NRF2, and HO-1, as well as suppressed the expression of IL-1β, TNF-α, and IL-6. MiR-30d-5p also restrained the apoptosis of impaired HKF. Conclusion: This study confirmed that miR-30d-5p could promote the M1/M2 polarization and inhibit the inflammatory response of impaired HKF, which provided a certain idea and direction for treating diabetes.

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Priyanka, S., R. Sudhagar, C. Vanniarajan, K. Ganesamurthy et J. Souframanien. « Induction of genetic variability for quantitative traits in horsegram (Macrotyloma uniflorum) through irradiation mutagenesis ». Journal of Environmental Biology 42, n^o 3 (4 mai 2021) : 597–608. http://dx.doi.org/10.22438/jeb/42/3/mrn-1491.

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Aim: The study was conducted to explore the magnitude of variability induced by gamma rays, electron beam and its combinations for quantitative traits in horsegram (Macrotyloma uniflorum (Lam) Verdc.). Methodology: The horsegram cultivar PAIYUR 2 was irradiated with twelve combinations involving G, EB and G+EB. Desirable mutagenic doses were identified in M1 based on plant injuries and forwarded to M2. Data on 11 yield component traits were recorded on normal looking M2 plants for identification of micro-mutants. Promising mutants were forwarded to M3 and the induced variability was ascertained using multivariate statistics. Results: Significant transgressive variants were observed in M2. The G+EB combination induced superior variants for yield. A positive shift in mean for yield and its attributing traits was observed in M3. Most of the polygenic traits were governed by additive gene effects. Interpretation: The increased mean for most of the polygenic traits in M3 population proved that selection made on early generation was highly effective. The isolated high yielding mutant progenies of selected families will contribute towards yield improvement in horsegram.

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PENNYCUICK, C. J. « Predicting Wingbeat Frequency and Wavelength of Birds ». Journal of Experimental Biology 150, n^o 1 (1 mai 1990) : 171–85. http://dx.doi.org/10.1242/jeb.150.1.171.

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Wingbeat frequencies were observed in the field for 32 morphologically diverse bird species, representing 18 families, and ranging in mass from 20 g to nearly 5 kg. A combination of multiple regression and dimensional analysis was used to show that wingbeat frequency (f) may be estimated by: f = 1.08(m1/3g1/2b−1S−1/4p−1/3 where m is the bird's body mass, g is the acceleration due to gravity, b is the wing span, S is the wing area and p is the air density. The predicted wingbeat frequency can be used to estimate the power available from a bird's flight muscles, and an estimate of the power required to fly can be obtained for comparison from the computer programs of Pennycuick (1989a). Field observations of airspeed are given for 30 of the 32 species. These are combined with the observations of wingbeat frequency to estimate wingbeat wavelength, and the ratio of wavelength to wing span, which is closely related to the ‘advance ratio’ as used by Ellington (1984).

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OFFIAH, NKECHI, et ABIODUN ADESIYUN. « Occurrence of Aflatoxins in Peanuts, Milk, and Animal Feed in Trinidad ». Journal of Food Protection 70, n^o 3 (1 mars 2007) : 771–75. http://dx.doi.org/10.4315/0362-028x-70.3.771.

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The prevalence of aflatoxin B1 (AFB1) in 186 peanut products (140 peanuts, 32 peanut butter, and 14 nut cakes) from supermarkets, road vendors, and sale outlets, and 40 feed samples from dairy farmers was determined using the radioimmunoassay method (Charm II) test for aflatoxins. The frequency of aflatoxin M1 (AFM1) was also determined in 175 raw milk samples from milk collection centers and 37 pasteurized milk samples obtained from supermarkets and sale outlets. Overall, from a total of 438 samples tested, 18 (4.1%) were positive for aflatoxin comprising 5 (2.2%) of 226 peanut products and feeds positive for AFB1, and 13 (6.1%) of 212 milk samples positive for AFM1. All 186 peanuts and peanut products were negative (0.0%) for AFB1 while 5 (7.4%) of 40 dairy feed samples were positive. Of the 175 raw milk samples tested, 13 (7.4%) were contaminated with AFM1 while all pasteurized milk samples were negative. The detection of AFB1 in feed and AFM1 in milk is of public health importance considering the practice of raw milk consumption by the farmers and their families in the country.

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Ji, Yanchun, Juanjuan Zhang, Jialing Yu, Ying Wang, Yuanyuan Lu, Min Liang, Qiang Li et al. « Contribution of mitochondrial ND1 3394T>C mutation to the phenotypic manifestation of Leber’s hereditary optic neuropathy ». Human Molecular Genetics 28, n^o 9 (31 décembre 2018) : 1515–29. http://dx.doi.org/10.1093/hmg/ddy450.

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Abstract Mitochondrial DNA (mtDNA) mutations have been associated with Leber’s hereditary optic neuropathy (LHON) and their pathophysiology remains poorly understood. In this study, we investigated the pathophysiology of a LHON susceptibility allele (m.3394T>C, p.30Y>H) in the Mitochondrial (MT)-ND1 gene. The incidence of m.3394T>C mutation was 2.7% in the cohort of 1741 probands with LHON. Extremely low penetrances of LHON were observed in 26 pedigrees carrying only m.3394T>C mutation, while 21 families bearing m.3394T>C, together with m.11778G>A or m.14484T>C mutation, exhibited higher penetrance of LHON than those in families carrying single mtDNA mutation(s). The m.3394T>C mutation disrupted the specific electrostatic interactions between Y30 of p.MT-ND1 with the sidechain of E4 and backbone carbonyl group of M1 of NDUFA1 (NADH dehydrogenase [ubiquinone] 1 alpha subcomplex subunit 1) of complex I, thereby altering the structure and function of complex I. We demonstrated that these cybrids bearing only m.3394T>C mutation caused mild mitochondrial dysfunctions and those harboring both m.3394T>C and m.11778G>A mutations exhibited greater mitochondrial dysfunctions than cybrids carrying only m.11778G>A mutation. In particular, the m.3394T>C mutation altered the stability of p.MT-ND1 and complex I assembly. Furthermore, the m.3394T>C mutation decreased the activities of mitochondrial complexes I, diminished mitochondrial ATP levels and membrane potential and increased the production of reactive oxygen species in the cybrids. These m.3394T>C mutation-induced alterations aggravated mitochondrial dysfunctions associated with the m.11778G>A mutation. These resultant biochemical defects contributed to higher penetrance of LHON in these families carrying both mtDNA mutations. Our findings provide new insights into the pathophysiology of LHON arising from the synergy between mitochondrial ND1 and ND4 mutations.

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Woghiren, A. I., R. O. ,. Awodoyin, C. I. Antiabong, E. N. Ngonadi, O. R. Jeminiwa et S. O. Olaoti-Laaro. « Effects of cowpea (Vigna unguiculata L. Walp.) as a Live mulch on weed management in maize cropping ». Nigerian Journal of Biotechnology 38, n^o 1 (27 juillet 2021) : 61–67. http://dx.doi.org/10.4314/njb.v38i1.7.

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Weed interference is a major constraint in maize cultivation. Living mulch as an alternative weed control strategy has been established to be environmentally safe but has not been widely used in maize cultivation. The aim of this research was to evaluate the weed management attributes of Vigna unguiculata in maize cropping. A field study was carried out in the crop garden of the Department of Crop Protection and Environmental Biology, University of Ibadan, Nigeria. The treatments were maize interplanted with Cowpea at 20,000 (M1), 30,000 (M2), 40,000 (M3) plants/hectare, hoe weeding (M4), weedy check (M5) and Primextra-2.5 L/ha (M6). The treatments were arranged in randomized complete block design, each replicated four times. Weed Dry Weight (WDW) and Weed Control Efficiency–WCE (%) were calculated following standardized methods. Data were analysed using descriptive statistics and ANOVA at α0.05. The treatment plots were dominated by weed species in the Asteraceae, Fabaceae and Poaceae families. The M5 accounted for the highest WDW (126.30 g). The WCE was highest in M3 (94.8%) and least in M5 (66.4%). Maize and cowpea interplant at 40,000 plants/hectare suppressed weed. Hence, cowpea is an ideal weed suppressant and can be inter-planted as a cover crop in maize cropping systems.

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Haga, Sachiko, Hiroko Kimoto et Kazushige Touhara. « Molecular characterization of vomeronasal sensory neurons responding to a male-specific peptide in tear fluid : Sexual communication in mice ». Pure and Applied Chemistry 79, n^o 4 (1 janvier 2007) : 775–83. http://dx.doi.org/10.1351/pac200779040775.

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Pheromonal signals received by the vomeronasal organ (VNO) have been shown to elicit various behavioral and physiological responses that are typically stereotyped and preprogrammed. Recently, we found a novel male-specific peptide, named exocrine gland-secreting peptide 1 (ESP1), that is secreted in tear fluid and stimulates the VNO in mice. Excreted ESP1 appears to be transferred to the female VNO, where it induces c-Fos expression and elicits an electrical response in a small subset of vomeronasal sensory neurons (VSNs). We report here the identification of molecular components expressed in ESP1-stimulated VSNs by double-staining with c-Fos. We found that the c-Fos-induced cells were localized amongst the Gαo-expressing VSNs. Furthermore, the ESP1 signal was received by VSNs expressing a single type of vomeronasal receptor type 2 (V2Rp5). Finally, double in situ hybridization of the V2Rp5 and various members of the M1 and M10 families of major histocompatibility complex (MHC) class Ib molecules revealed that V2Rp5-expressing VSNs can express multiple MHC molecules. These results suggest that a V2R rather than MHC molecule is mainly responsible for the recognition of ESP1. The identification of the putative sex-pheromone ESP1 and its cognate receptor therefore will help clarify the molecular mechanisms underlying pheromone recognition in the mouse vomeronasal system.

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Tetyannikov, N. V., et N. A. Bome. « Studies on mutagenic effect of phosphemide in barley ». Proceedings on applied botany, genetics and breeding 183, n^o 4 (20 décembre 2022) : 141–51. http://dx.doi.org/10.30901/2227-8834-2022-4-141-151.

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Background. The method of induced mutagenesis is used to temporarily increase the frequency of mutations, allowing a higher probability of obtaining plants with new alleles and traits valuable for breeding. The search for new agents with high mutagenic activity is of particular interest for the development of mutational breeding. A new mutagen for barley is phosphemide.Materials and methods. Field and laboratory studies were conducted in 2016–2018. Three barley genotypes were treated with an aqueous solution of phosphemide at two concentrations: 0.002% and 0.01%, exposure: 3 hours. Experimental data were statistically processed by the analysis of variance (ANOVA) using Statistica 7. The error of the mean (Sx) was calculated for the mean values. Significance of differences (P < 0.05) was determined by Student’s t-test. Mutation frequency (Mf), mutagenic effectiveness (ME), and efficiency (Me) were assessed.Results and conclusion. It was found that the greatest contribution to formation of field seed germination of mutant populations in M1 and M2 generations was made by the mutagenic factor (20,36%) and interaction of the genotype × environment (18,55%) and mutagen × environment factors (14,93%). The concentration of 0.01% was recognized as semi-lethal for two accessions. In the M2 generation, the mutagenic effectiveness of the 0.002% phosphemide concentration exceeded that of 0.01% more than 4 times. The low concentration was more effective for cv. ‘Zernogradsky 813’ (17.43%) and accession Dz02- 129 (12.04%). For C.I. 10995, a higher concentration of phosphemide had greater effect (29.66%) providing a high mutation frequency (9.79%) against a relatively low lethality (33.00%). Nine different types were identified in the mutation spectrum. In M3 generation, distinct inheritance of the changes was confirmed in 46.43% of families. The highest number of families with confirmed changes was recorded for C.I. 10995 in the experiment with a higher concentration.

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Tetyannikov, N. V., et N. A. Bome. « Studies on mutagenic effect of phosphemide in barley ». Proceedings on applied botany, genetics and breeding 183, n^o 4 (20 décembre 2022) : 144–51. http://dx.doi.org/10.30901/2227-8834-2022-4-144-151.

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Background. The method of induced mutagenesis is used to temporarily increase the frequency of mutations, allowing a higher probability of obtaining plants with new alleles and traits valuable for breeding. The search for new agents with high mutagenic activity is of particular interest for the development of mutational breeding. A new mutagen for barley is phosphemide.Materials and methods. Field and laboratory studies were conducted in 2016–2018. Three barley genotypes were treated with an aqueous solution of phosphemide at two concentrations: 0.002% and 0.01%, exposure: 3 hours. Experimental data were statistically processed by the analysis of variance (ANOVA) using Statistica 7. The error of the mean (Sx) was calculated for the mean values. Significance of differences (P < 0.05) was determined by Student’s t-test. Mutation frequency (Mf), mutagenic effectiveness (ME), and efficiency (Me) were assessed.Results and conclusion. It was found that the greatest contribution to formation of field seed germination of mutant populations in M1 and M2 generations was made by the mutagenic factor (20,36%) and interaction of the genotype × environment (18,55%) and mutagen × environment factors (14,93%). The concentration of 0.01% was recognized as semi-lethal for two accessions. In the M2 generation, the mutagenic effectiveness of the 0.002% phosphemide concentration exceeded that of 0.01% more than 4 times. The low concentration was more effective for cv. ‘Zernogradsky 813’ (17.43%) and accession Dz02- 129 (12.04%). For C.I. 10995, a higher concentration of phosphemide had greater effect (29.66%) providing a high mutation frequency (9.79%) against a relatively low lethality (33.00%). Nine different types were identified in the mutation spectrum. In M3 generation, distinct inheritance of the changes was confirmed in 46.43% of families. The highest number of families with confirmed changes was recorded for C.I. 10995 in the experiment with a higher concentration.

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Yangua-Solano, Erika, Vinicio Carrión-Paladines et Ángel Benítez. « Effects of Fire on Pyrodiversity of Terricolous Non-Tracheophytes Photoautotrophs in a Páramo of Southern Ecuador ». Diversity 15, n^o 12 (27 novembre 2023) : 1176. http://dx.doi.org/10.3390/d15121176.

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The páramos have a great diversity of flora, including terricolous non-tracheophyte photoautotrophs (bryophytes and lichens). Bryophytes and lichens are very sensitive to environmental changes related to anthropogenic fires, livestock, and agricultural activities. We determined for the first time in Ecuador the effects of prescribed fires on the pyrodiversity of terricolous non-tracheophyte photoautotroph in a páramo of South Ecuador. Three permanent sampling plots (T1, T2, and control) were established, each with a dimension of 4 m × 20 m and separated by 3 m (T1: one with fire-induced uphill and T2: one with fire-induced downhill and one control). They were installed in three different blocks, obtaining a total of nine plots. Three samplings (2, 6, and 12 months) were carried out in each plot, where the cover and richness of terricolous bryophytes and lichens were estimated in 216 quadrats of 20 × 30 cm. A total of 27 species (11 lichens and 16 bryophytes) were studied, where the lichen families, that is, Cladoniaceae and Baeomycetaceae, as well as the bryophytes families, namely, Dicranaceae, Jungermanniaceae, Bartramiaceae, Rhacocarpaceae, and Pallaviciniaceae, have been recorded as pioneers in areas under fire effects. Richness and diversity (calculated using the Shannon–Weaver and Simpson indexes) were affected by fire treatments; on the other hand, monitoring time (M3) positively affected species diversity. The composition of terrestrial non-tracheophyte photoautotroph communities showed slight changes between the control and T1 and T2, but the changes were more marked with time after the burns (M1 vs. M3), related to fire severity. Therefore, terricolous lichen and bryophyte communities (richness and diversity) can be used as model organisms for the assessment of the effects of prescribed fires on tropical páramos for subsequent management and conservation.

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Cimino, Silvia, Luca Cerniglia, Giulia Ballarotto, Eleonora Marzilli, Esterina Pascale, Claudio D’Addario, Walter Adriani, Angelo Giovanni Icro Maremmani et Renata Tambelli. « Children’s DAT1 Polymorphism Moderates the Relationship Between Parents’ Psychological Profiles, Children’s DAT Methylation, and Their Emotional/Behavioral Functioning in a Normative Sample ». International Journal of Environmental Research and Public Health 16, n^o 14 (18 juillet 2019) : 2567. http://dx.doi.org/10.3390/ijerph16142567.

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Parental psychopathological risk is considered as one of the most crucial features associated with epigenetic modifications in offspring, which in turn are thought to be related to their emotional/behavioral profiles. The dopamine active transporter (DAT) gene is suggested to play a significant role in affective/behavioral regulation. On the basis of the previous literature, we aimed at verifying whether children’s DAT1 polymorphisms moderated the relationship between parents’ psychological profiles, children’s emotional/behavioral functioning, and DAT1 methylation in a normative sample of 79 families with school-age children (Ntot = 237). Children’s biological samples were collected through buccal swabs, while Symptom Check-List-90 item Revised, Adult Self Report, and Child Behavior Check-List/6–18 was administered to assess parental and children’s psychological functioning. We found that higher maternal externalizing problems predicted the following: higher levels of children’s DAT1 methylation at M1, but only among children with 10/10 genotype; higher levels of methylation at M2 among children with 10/10 genotype; while lower levels for children with a 9-repeat allele. There was also a positive relationship between fathers’ externalizing problems and children’s externalizing problems, only for children with a 9-repeat allele. Our findings support emerging evidence of the complex interplay between genetic and environmental factors in shaping children’ emotional/behavioral functioning, contributing to the knowledge of risk variables for a child’s development and psychological well-being.

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Lyukmanova, E. N., Z. O. Shenkarev, N. F. Khabibullina, D. S. Kulbatskiy, M. A. Shulepko, L. E. Petrovskaya, A. S. Arseniev, D. A. Dolgikh et M. P. Kirpichnikov. « N-Terminal Fusion Tags for Effective Production of G-Protein-Coupled Receptors in Bacterial Cell-Free Systems ». Acta Naturae 4, n^o 4 (15 décembre 2012) : 58–64. http://dx.doi.org/10.32607/20758251-2012-4-4-58-64.

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G-protein-coupled receptors (GPCR) constitute one of the biggest families of membrane proteins. In spite of the fact that they are highly relevant to pharmacy, they have remained poorly explored. One of the main bottlenecks encountered in structural-functional studies of GPCRs is the difficulty to produce sufficient amounts of the proteins. Cell-free systems based on bacterial extracts from E. coli cells attract much attention as an effective tool for recombinant production of membrane proteins. GPCR production in bacterial cell-free expression systems is often inefficient because of the problems associated with the low efficiency of the translation initiation process. This problem could be resolved if GPCRs were expressed in the form of hybrid proteins with N-terminal polypeptide fusion tags. In the present work, three new N-terminal fusion tags are proposed for cellfree production of the human 2-adrenergic receptor, human M1 muscarinic acetylcholine receptor, and human somatostatin receptor type 5. It is demonstrated that the application of an N-terminal fragment (6 a.a.) of bacteriorhodopsin from Exiguobacterium sibiricum (ESR-tag), N-terminal fragment (16 а.о.) of RNAse A (S-tag), and Mistic protein from B. subtilis allows to increase the CF synthesis of the target GPCRs by 538 times, resulting in yields of 0.63.8 mg from 1 ml of the reaction mixture, which is sufficient for structural-functional studies.

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Porcella, Stephen F., Cecily A. Fitzpatrick et James L. Bono. « Expression and Immunological Analysis of the Plasmid-Borne mlp Genes of Borrelia burgdorferiStrain B31 ». Infection and Immunity 68, n^o 9 (1 septembre 2000) : 4992–5001. http://dx.doi.org/10.1128/iai.68.9.4992-5001.2000.

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ABSTRACT A lipoprotein gene family first identified in Borrelia burgdorferi strain 297, designated 2.9 LP and recently renamed mlp, was found on circular and linear plasmids in the genome sequence of B. burgdorferistrain B31-M1. Sequence analyses of the B31 mlp genes and physically linked variant gene families indicated that mlpgene heterogeneity is unique and unrelated to location or linkage to divergent sequences. Evidence of recombination between B31mlp alleles was also detected. Northern blot analysis of cultured strain B31 indicated that the mlp genes were not expressed at a temperature (23°C) characteristic of that of ticks in the environment. In striking contrast, expression of manymlp genes increased substantially when strain B31 was shifted to 35°C, a temperature change mimicking that occurring in the natural transmission cycle of the spirochete from tick to mammal. Primer extension analysis of the mlp mRNA transcripts suggested that sigma 70-like promoters are involved inmlp expression during temperature shift conditions. Antibodies were made against strain B31 Mlp proteins within the first 4 weeks after experimental mouse infection. Importantly, Lyme disease patients also had serum antibodies reactive with purified recombinant Mlp proteins from strain B31, a result indicating that humans are exposed to Mlp proteins during infection. Taken together, the data indicate that strain B31 mlp genes encode a diverse array of lipoproteins which may participate in early infection processes in the mammalian host.

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Sękowska, Alicja, Tomasz Bogiel et Eugenia Gospodarek-Komkowska. « Evaluation of eazyplex® SuperBug CRE Test for Beta-Lactamase Genes Detection in Klebsiella spp. and P. aeruginosa Strains ». Current Microbiology 77, n^o 1 (14 novembre 2019) : 99–103. http://dx.doi.org/10.1007/s00284-019-01806-5.

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AbstractThe multi-drug resistance of Gram-negative rods is one of the most important issues of present medicine. In recent years, more and more strains resistant to the majority or to all possible therapeutic options have been isolated—especially Klebsiella spp. and Pseudomonas spp. representatives. It is very important to detect strains with these phenotypes as quickly and reliably as possible. The aim of the study was to evaluate the usefulness of eazyplex® SuperBug CRE test (Amplex Diagnostics) for the detection of the most important beta-lactam resistance genes. eazyplex® SuperBug CRE test is based on the loop-mediated isothermal amplification (LAMP) method, and detects genes for the following beta-lactamases: KPC, NDM-1, VIM, OXA-48, CTX-M1, CTX-M9 and OXA-181. The study involved 87 strains. For all of the positive strains in the LAMP method, additional PCR were performed to increase the spectrum of ESBLs detected by the genes encoding for enzymes belonging to TEM and SHV families. The results obtained by the tested method and standard PCR were consistent for all Klebsiella spp. strains. The discrepancy between the evaluated test and PCR results was observed for one P. aeruginosa strain. The eazyplex® SuperBug CRE test can be used for quick detection of the most important beta-lactam resistance mechanisms amongst Gram-negative rods.

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González-Rivera, Christian, Holly M. Scott Algood, Jana N. Radin, Mark S. McClain et Timothy L. Cover. « The Intermediate Region of Helicobacter pylori VacA Is a Determinant of Toxin Potency in a Jurkat T Cell Assay ». Infection and Immunity 80, n^o 8 (14 mai 2012) : 2578–88. http://dx.doi.org/10.1128/iai.00052-12.

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ABSTRACTColonization of the human stomach withHelicobacter pyloriis a risk factor for peptic ulceration, noncardia gastric adenocarcinoma, and gastric lymphoma. The secreted VacA toxin is an importantH. pylorivirulence factor that causes multiple alterations in gastric epithelial cells and T cells. Several families ofvacAalleles have been described, andH. pyloristrains containing certainvacAtypes (s1, i1, and m1) are associated with an increased risk of gastric disease, compared to strains containing othervacAtypes (s2, i2, and m2). Thus far, there has been relatively little study of the role of the VacA intermediate region (i-region) in toxin activity. In this study, we compared the ability of i1 and i2 forms of VacA to cause functional alterations in Jurkat cells. To do this, we manipulated the chromosomalvacAgene in twoH. pyloristrains to introduce alterations in the region encoding the VacA i-region. We did not detect any differences in the capacity of i1 and i2 forms of VacA to cause vacuolation of RK13 cells. In comparison to i1 forms of VacA, i2 forms of VacA had a diminished capacity to inhibit the activation of nuclear factor of activated T cells (NFAT) and suppress interleukin-2 (IL-2) production. Correspondingly, i2 forms of VacA bound to Jurkat cells less avidly than did i1 forms of VacA. These results indicate that the VacA i-region is an important determinant of VacA effects on human T cell function.

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del Luján, Irma, Susana Mabel SMP Pérez, Sabrina SB Botta, Virginia VR Rescia, Mauro MD Davoli et Angela Cristina ACM Milani. « Molecular Characterization in Two Families Bearing Glucose-6-Phosphate Dehydrogenase Deficiency (G6PD) IN Rosario, Argentina. » Blood 114, n^o 22 (20 novembre 2009) : 5093. http://dx.doi.org/10.1182/blood.v114.22.5093.5093.

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Abstract Abstract 5093 Introduction: G6PD deficiency is a frequent worldwide enzymopathy, with sex-linked inheritance, the gene that codifies the enzyme localizes at the X chromosome. Males are hemizygous (Hem) for disease, while women are heterozygous (Het), i.e. carriers, and very rarely homozygous, or double heterozygous and consequently, develop disease. There are over 120 deficient molecular variants observed in Afro-Americans and in the malaria endemic region of the Mediterranean Basin. In previous studies in Argentina we have reported a low prevalence, 0,2-0,3 %, although the predominant molecular variants are unknown. Most of deficiencies are clinically detected when the patient is submitted to oxidative stress produced by infections, therapeutic drugs, or Vicia fava ingestion, develops an acute hemolytic anemia (AHA) of variable severity. Materials and Methods: Two male patients and their families were studied. 1) A1: 45y aged male, with AHA after bean ingestion, as well as the following relatives: mother (M1); sister (S1); three nephews (N1, N2, N3) and a niece (N4) without positive AHA history. 2) A2: 55y aged male, with two AHA episodes in childhood and adolescence, one of them associated with an infection, and the mother (M2). The evaluation clinical and hematological of the patients were normal Laboratory assays: Hemogram, Hemoglobin (Hb) (Coulter AcT10); Reticulocytes (Ret); Brewer test (B.T.); Heinz bodies (HB); Cytochemical method modified (Gurbuz, N; et al): NV: 86,8 % positive cells (CYT); Enzymatic activity (EA) Kinetic Method (Beutler-OMS): NV: 8.0±1.6 G6PD/gHb IU and Polymerase Chain Reaction with Enzyme Restriction (PCR-ER) for characterization of different variants: G6PDMed(563G□T), G6PD A376(A□G), G6PD A376(A□G) 202(G□A); G6PD A 376(A□G) 680 (G□T) y G6PD A 376(A□G) 968 (T□C). Results: Conclusions: The EA confirmed the deficit of probands and nephews N1 and N3 without previous AHA history. The heterozygous character of females was not defined by this method but PCR-ER and CYT mod. supported the obliged carriers heterozygosis and the potential ones, demonstrating that CYT is more sensitive for carrier detection than other screening techniques or EA. The deficient phenotype was correlated with the detected variants, since the Mediterranean G6PD: G6PD Med(563G□T) (Type II, OMS) and G6PD A376(A□G) 202(G□A) (Type III, OMS) are associated with AHA induced by infections or Vicia Fava ingestion. The finding in Argentina of these two variants, that are frequent in the Mediterranean region, it is in accordance with the fact that our population has mainly Italian, Spanish (family 1) and Jewish (family 2) ancestors. The detection of deficient without hemolysis, as well as carriers is of the utmost importance in genetic counseling. Disclosures: No relevant conflicts of interest to declare.

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Diachenko, O. B., J. F. Rivis, G. V. Tesak et O. I. Stadnytska. « Specificities of accumulation of essential polyunsaturated fatty acids of ω-3 and ω-6 families in the tissues of bulls after supplementing their diet with the sources of fatty acids and mineral elements ». Agricultural Science and Practice 10, n^o 2 (1 novembre 2023) : 62–71. http://dx.doi.org/10.15407/agrisp10.02.062.

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Aim. To determine the intensity of growth of fattening bulls and the specificities of the accumulation of essential polyunsaturated fatty acids from the ω-3 and ω-6 families in their tissues after supplementing their diet with the sources of essential fatty acids and copper sulfate to increase their meat productivity and improve the biological value of beef. Methods. The study was conducted using the methodological approaches, common for international practice in accordance with the requirements of ISO 17025, and using the conventional methods of peer groups involving clinically healthy animals. The content of polyunsaturated fatty acids of the ω-3 and ω-6 families was determined by gas chro- matography using the Chrom-5 device. Copper content was determined by the method of atomic absorption spectro- photometry using the Selmi C-115 M1 device. Results. It was found that the introduction of linseed oil (as a source of α-linolenic acid, which is a precursor of polyunsaturated fatty acids of the ω-3 family) and sunflower oil (as a source of linoleic acid, which is a precursor of polyunsaturated fatty acids of the ω-6 family), the synthetic substance doxane (as an inhibitor of biohydrogenation processes in unsaturated fatty acids in the rumen) and pentahydrate copper sulfate (as a source of copper) to the diet of young fattening cattle caused a probable increase in the content of biologically active polyunsaturated fatty acids of the ω-3 and ω-6 family and copper in their liver and skeletal muscles. At the same time, the increase in the content of biologically active polyunsaturated fatty acids of the ω-3 and ω-6 families and copper in the abovementioned tissues due to the stimulation of metabolic processes in the body contributed to a probable increase in the average daily weight gain of young fattening animals. Thus, there was a direct relationship between the content of α-linolenic and linoleic acids and copper in the diet and their content in the tissues of experimental animals, productivity characteristics, and biological value of beef. Conclusions. The introduction of a mixture of linseed and sunflower oils into the diet of fattening bulls led to an increase in the content of α-linolenic and linoleic acids and a 1.7-fold decrease in the ratio between essential polyunsaturated fatty acids of the ω-6 family and that of the ω-3 family. The increase in the content of copper and essential polyunsaturated fatty acids of the ω-6 and ω-3 families in the diet of fattening bulls led to their accumulation in the liver and skeletal muscles, which contributed to the enhanced biological value of beef.

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Suzhaeva, L. V., et S. A. Egorova. « Antimicrobial resistance of Escherichia coli, isolated from children’s intestinal microbiota ». Russian Clinical Laboratory Diagnostics 65, n^o 10 (17 septembre 2020) : 638–44. http://dx.doi.org/10.18821/0869-2084-2020-65-10-638-644.

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Recent studies have shown that bacterial resistance existed long before antimicrobials were used in medicine, and not only pathogens are resistant to antibiotics. 511 strains of E. coli isolated from the intestinal microbiota of children aged 1 month to 17 years living in St. Petersburg were studied: the susceptibility to 15 antibiotics was determined by the disk diffusion method, as well as the susceptibility to 6 commercial bacteriophages produced by «Microgen» (Russia). The b-lactamase genes of molecular families TEM, SHV, OXA, and CTX-M were detected by multiplex PCR. 39,3% E. coli isolates were resistant to one or more antimicrobial classes. The proportion of multidrug resistant isolates (resistant to 3 or more classes) was 16,6%. Multidrug resistance to clinically significant antimicrobial classes (extended-spectrum cephalosporins (ESC) + fluoroquinolones + aminoglycosides) was detected in 0,8% isolates. Resistance to aminopenicillins was detected in 29,5%, ESC - 11,2%, fluoroquinolones - 13,3%, tetracycline - 20,0%, chloramphenicol - 9,8%, aminoglycosides - 2,5% isolates. b-lactam resistance was due to the beta-lactamase production: to ampicillin - the molecular family TEM (81,9%), ESC - the CTX-M molecular family (87,7%) CTX-M1 - (66%) and CTX-M9 groups (34%). 43,5% multidrug resistant E. coli isolates were susceptible to at least one of the six commercial bacteriophages produced by «Microgen». The study showed that the intestinal microbiota of children is an important reservoir of E. coli resistant (including multidrug resistance) to various classes of antibiotics, and bacteriophage therapy is an alternative method for eradication of antibiotic-resistant E. coli.

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