Inhibition of geranylgeranyl diphosphate synthesis in in vitro systems

The incorporation of [14C]mevalonate and [14C]isopentenyl diphosphate into geranylgeranyl diphosphate was investigated in in vitro systems from Cucurbita pepo (pumpkin) endosperm and from Avena sativa etioplasts. Mevalonate incorporation was effectively inhibited in the pumpkin system by geranylgeranyl diphosphate and geranylgeranyl monophosphate but less effectively by phytyl diphosphate or inorganic diphosphate. Membrane lipids, geranyllinalool, or lecithin enhanced mevalonate incorporation in the Cucurbita system. Incorporation of isopentenyl diphosphate was also enhanced by lecithin and inhibited by geranylgeranyl diphosphate in the Cucurbita system. No lipid enhancement was found in the Avena system; inhibition by GGPP required a much higher GGPP concentration than in the Cucurbita system

MPEG-7 Description of Generic Video Objects for Scene Reconstruction

ABSTRACT We present an MPEG-7 compliant description of generic video sequences aiming at their scalable transmission and reconstruction. The proposed method allows efficient and flexible video coding while keeping the advantages of textual descriptions in database applications. Visual objects are described in terms of their shape, color, texture and motion; these features can be extracted automatically and are sufficient in a wide range of applications. To permit partial sequence reconstruction, at least one simple qualitative as well as a quantitative descriptor is provided for each feature. In addition, we propose a structure for the organization of the descriptors into objects and scenes and some possible applications for our method. Experimental results obtained with news and video surveillance sequences validate our method and highlight its main features

Cooperative virulence can emerge via horizontal gene transfer but is stabilized by transmission

Intestinal inflammation fuels Salmonella Typhimurium ( S .Tm) transmission despite a fitness cost associated with the expression of virulence. Cheater mutants can emerge that profit from inflammation without enduring this cost. Intestinal virulence in S .Tm is therefore a cooperative trait, and its evolution a conundrum. Horizontal gene transfer (HGT) of cooperative alleles may facilitate the emergence of cooperative virulence, despite its instability. To test this hypothesis, we cloned hilD , coding for a master regulator of virulence, into a conjugative plasmid that is highly transferrable during intestinal colonization. We demonstrate that virulence can emerge by hilD transfer between avirulent strains in vivo . However, this was indeed unstable and hilD mutant cheaters arose within a few days. The timing of cheater emergence depended on the cost. We further show that stabilization of cooperative virulence in S .Tm is dependent on transmission dynamics, strengthened by population bottlenecks, leading cheaters to extinction and allowing cooperators to thrive

Ergebnisse aus Versuchen an mit OSB/3 beplankten Holzrahmenbau-Wänden

Für eine erdbebengerechte Bemessung von Tragwerken nach dem Konzept des duktilen Tragwerksverhalten muss eine genügende Energiedissipation sichergestellt werden. Holzrahmenbau- Wände können für die Sicherstellung der Energiedissipation angesetzt werden, wenn sie für ein duktiles Versagen bemessen und konstruiert werden. Gemäss der Norm SIA 265, 2021 darf die Duktilität der Verankerung nicht angesetzt werden, weshalb die Duktilität nur mit der Verbindung zwischen Beplankung und Ständerwerk sichergestellt wird. Für ein duktiles Versagen der Holzrahmenbau-Wand muss garantiert werden, dass die Verbindung zwischen Beplankung und Ständerwerk das schwächste Glied der gesamten Wandscheibe ist und alle anderen Elemente überbemessen sind

Neonatal Hemolytic Uremic Syndrome After Mother-to-Child Transmission of a Low-Pathogenic stx2b Harboring Shiga Toxin-Producing Escherichia coli

This case describes evidence for a Shiga toxin-producing Escherichia coli (STEC) O146:H28 infection leading to hemolytic uremic syndrome in a neonate. STEC O146:H28 was linked hitherto with asymptomatic carriage in humans. Based on strain characteristics and genotyping data, the mother is a healthy carrier who transmitted the STEC during delivery. STEC strains belonging to the low-pathogenic STEC group must also be considered in the workup of neonatal hemolytic uremic syndrom

Exame histopatológico do endométrio da égua após infecções experimentais repetidas e cinco diferentes tratamentos: aspectos inflamatórios

A endometrite é uma importante causa de subfertilidade na égua. O objetivo deste trabalho foi verificar o efeito de diferentes tratamentos sobre o endométrio de éguas infectadas experimentalmente. Foram utilizadas vinte éguas resistentes, com histórico reprodutivo desconhecido, e cinco éguas susceptíveis, com histórico de endometrites recorrentes e subfertilidade. Após o primeiro exame histopatológico os ciclos foram sincronizados com prostaglandina. Na fase estral, as éguas foram infectadas com 1 x 10 9 Streptococcus equi. Vinte e quatro horas após a infecção, os animais eram submetidos aos exames clínico, bacteriológico e citológico. Constatada a presença de sinais clínicos de endometrite, os grupos de éguas foram distribuídos entre cinco diferentes tratamentos: leucócitos frescos, leucócitos congelados, leucócitos lisados, Interleucina-8 e grupo controle. As éguas foram tratadas diariamente, por no máximo, quatro dias, ou até que o exame bacteriológico não evidenciasse o crescimento de Streptococcus. No quinto dia, as éguas eram então submetidas a novo exame histopatológico e, no sétimo, dia todas as éguas eram tratadas com penicilina, independentemente de terem eliminado a infecção ou não. Sete dias após, as éguas eram novamente submetidas a exame histopatológico e sincronizadas para realizar uma nova infecção e novo tratamento. As biópsias foram avaliadas quanto à endometrite. Conclui-se que éguas susceptíveis à endometrite, com presença de Streptococcus no útero, não apresentam neutrofilia após cinco dias de infecção. Provavelmente o menor tempo de eliminação bacteriana observado nos tratamentos com leucócitos frescos e congelados deva-se a outros fatores que não o efeito quimioatraente dessas células

β-Decay Half-Lives of 110 Neutron-Rich Nuclei across the N = 82 Shell Gap: Implications for the Mechanism and Universality of the Astrophysical r Process

G. Larusso et al.; 7 pags.; 5 figs.; 2 tabs.; PACS numbers: 23.40.-s, 26.30.Hj, 27.60.+j© 2015 American Physical Society. The β-decay half-lives of 110 neutron-rich isotopes of the elements from 37Rb to 50Sn were measured at the Radioactive Isotope Beam Factory. The 40 new half-lives follow robust systematics and highlight the persistence of shell effects. The new data have direct implications for r-process calculations and reinforce the notion that the second (A ≈ 130) and the rare-earth-element (A ≈ 160) abundance peaks may result from the freeze-out of an (n, γ) ⇄ (γ,n) equilibrium. In such an equilibrium, the new half-lives are important factors determining the abundance of rare-earth elements, and allow for a more reliable discussion of the r process universality. It is anticipated that universality may not extend to the elements Sn, Sb, I, and Cs, making the detection of these elements in metal-poor stars of the utmost importance to determine the exact conditions of individual r-process events.Part of the WAS3ABi was supported by the Rare Isotope Science Project which is funded by the Ministry of Education, Science, and Technology (MEST) and National Research Foundation (NRF) of Korea. This work was partially supported by KAKENHI (Grants No. 25247045, No. 2301752, and No. 25800130), the RIKEN Foreign Research Program, the Spanish Ministerio de Ciencia e Innovación (Contracts No. FPA2009-13377-C02 and No. FPA2011-29854-C04), the U.S. Department of Energy, Office of Science, Office of Nuclear Physics, Contract No. DE-AC02-06CH11357, the NASA Grant No. NNX10AH78G, and the Hungarian Scientific Research Fund OTKA Contract No. K100835.Peer Reviewe

Effects of Manganese Porphyrins on Cellular Sulfur Metabolism

Manganese porphyrins (MnPs), MnTE-2-PyP5+, MnTnHex-2-PyP5+ and MnTnBuOE-2-PyP5+, are superoxide dismutase (SOD) mimetics and form a redox cycle between O2 and reductants, including ascorbic acid, ultimately producing hydrogen peroxide (H2O2). We previously found that MnPs oxidize hydrogen sulfide (H2S) to polysulfides (PS; H2Sn, n = 2–6) in buffer. Here, we examine the effects of MnPs for 24 h on H2S metabolism and PS production in HEK293, A549, HT29 and bone marrow derived stem cells (BMDSC) using H2S (AzMC, MeRho-AZ) and PS (SSP4) fluorophores. All MnPs decreased intracellular H2S production and increased intracellular PS. H2S metabolism and PS production were unaffected by cellular O2 (5% versus 21% O2), H2O2 or ascorbic acid. We observed with confocal microscopy that mitochondria are a major site of H2S production in HEK293 cells and that MnPs decrease mitochondrial H2S production and increase PS in what appeared to be nucleoli and cytosolic fibrillary elements. This supports a role for MnPs in the metabolism of H2S to PS, the latter serving as both short- and long-term antioxidants, and suggests that some of the biological effects of MnPs may be attributable to sulfur metabolism