Proses Produksi Dan Pengemasan Yoghurtdicv. Cita Nasional Salatiga

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Controlled Reduction of Tertiary Amides to the Corresponding Alcohols, Aldehydes, or Amines Using Dialkylboranes and Aminoborohydride Reagents

Dialkylboranes and aminoborohydrides are mild, selective reducing agents complementary to the commonly utilized amide reducing agents, such as lithium aluminum hydride (LiAlH₄) and diiso­butyl­aluminum hydride (DIBAL) reagents. Tertiary amides were reduced using 1 or 2 equiv of various dialkylboranes. The reduction of tertiary amides required 2 equiv of 9-bora­bicyclo­[3.3.1]­nonane (9-BBN) for complete reduction to give the corresponding tertiary amines. One equivalent of sterically hindered disiamylborane reacts with tertiary amides to afford the corresponding aldehydes. Aminoborohydrides are powerful and selective reducing agents for the reduction of tertiary amides. Lithium dimethyl­amino­boro­hydride and lithium diiso­propyl­amino­borohydride are prepared from <i>n</i>-butyllithium and the corresponding amine-borane. Chloro­magnesium dimethyl­amino­borohydride (ClMg⁺­[H₃B-NMe₂]⁻, MgAB) is prepared by the reaction of dimethylamine-borane with methylmagnesium chloride. Solutions of amino­boro­hydride reduce aliphatic, aromatic, and heteroaromatic tertiary amides to give the corresponding alcohol, amine, or aldehyde depending on the steric requirement of the tertiary amide and the amino­borohydride used

Intestinal <i>Sirt1</i> deletion impacts on the development of colorectal cancer.

<p><b>A–B,</b> Schematic representation of the AOM/DSS protocol (top left panel) and representative image of colons from <i>Sirt1^int−/−</i> and control mice after CAC induction (Bar = 200 µm) (bottom left panel). <i>Sirt1^int−/−</i> mice show significantly less tumors (right panel). <b>B</b>, Representative picture of a colon section from a <i>Sirt1^int−/−</i> and control mouse after CAC induction (left panels). Tumor size (right panel). <b>C,</b> Colon length at the time of sacrifice (AOM/DSS). <b>D,</b> Percentage of body weight change. For the AOM/DSS experiment 8 mice for each genotype were used. *P<0.05; **P<0.01; ***P<0.001. <b>E–F,</b> Principal Coordinate Analysis (PCA) of bacterial sequences from colon tissue performed using unweighted UniFrac distance matrix. <b>E</b>, <i>Sirt1^int−/−</i> colon tissue before and after AOM treatment (PERMANOVA p = 0.003, ANOSIM p = 0.016). <b>F</b>, <i>Sirt1^L2/L2</i> colon tissue with and without AOM treatment (PERMANOVA p = 0.067, ANOSIM p = 0.038). <b>G–H,</b> Most statistically significant OTUs before and after AOM in both <i>Sirt1^L2/L2</i> (<b>G</b>), and <i>Sirt1^int−/−</i> (<b>H</b>), colon tissues; *Indicates <i>Helicobacter</i> and <i>Desulfovibrio</i> (see also Table S4 in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0102495#pone.0102495.s005" target="_blank">File S1</a>). <b>I,</b> PCA of bacterial sequences from colon tissue after AOM (PERMANOVA p = 0.767, ANOSIM p = 0.167).</p

Hyper-acetylation by SIRT1 stabilizes SPDEF and triggers Paneth and goblet cells maturation.

<p><b>A,</b> SPDEF target genes (<i>Slug, uPA, Ccl6</i>) are induced in <i>Sirt1^int−/−</i> intestines. GIF1 (<i>Nrg3, Pax6, ChgA</i>) and SOX9 (<i>Igfbp4</i>) target genes, as well as <i>Spdef</i> are not changed. <b>B,</b> In vitro acetylation/deacetylation assays demonstrates that p300 acetylates SPDEF and SIRT1, but not SIRT6 and SIRT7, deacetylates SPDEF. <b>C</b>, Nano-LC-MS/MS shows SIRT1-dependent in vitro deacetylation of AcK294 (left panel). Sequence alignment showing the evolutionary conserved K294 residue (right panel). <b>D,</b> SIRT1, but not SIRT1G261A, deacetylates SPDEF in HEK293 immunoprecipitates. The SPDEFK294Q mutant is not acetylated. Tubulin was used as loading control. <b>E–F</b> SPDEF, SPDEFK294Q, and SIRT1 were transfected in the HEK293 cell line and visualized by immunoblotting before (0 min) and after cycloheximide (CHX) treatment. HSP90 is used as loading control (left panels in E and F). The relative stability of SPDEF or SPDEFK294Q was calculated by ImageJ (right panels in E and F). <b>G,</b> PC3 cells were co-transfected with an E-Cadherin promoter luciferase reporter construct, wild type or SPDEFK294Q in presence or absence of SIRT1. SIRT1 represses SPDEF-dependent reporter activation. The acetylated-mimic SPDEFK294Q mutant is constitutively activate and not affected by SIRT1. <b>H</b>, Immunoblotting of crypt enriched fractions from <i>Sirt1^int−/−</i> and <i>Sirt1^L2/L2</i> mice show increased SPDEF protein levels in <i>Sirt1^int−/−</i> intestines. β-Actin was used as loading control. Results are expressed as mean±SEM. *P<0.05; **P<0.01; ***P<0.001.</p