Les normes, comment?

La description normalisée des ressources d’enseignement et d’apprentissage requiert l’utilisation d’outils d’implantation conformes aux conventions d’un standard ou d’une norme internationale et un réseau d’entraide et d’accompagnement

Non-clinical pharmacokinetic profiles of rovatirelin, an orally available thyrotropin-releasing hormone analogue

<p>1.The non-clinical pharmacokinetic profiles of rovatirelin, a novel thyrotropin-releasing hormone (TRH) analogue, were investigated <i>in vivo</i> and <i>in vitro</i>.</p> <p>2.Rovatirelin orally administered to rats and dogs was rapidly absorbed and bioavailability was estimated to be 7.3 and 41.3%, respectively. The extent of plasma protein binding of rovatirelin in rats, dogs, and humans was low in all species (∼15%). The permeability of rovatirelin from blood to brain (permeability-surface area) ranged from 1.04 ± 0.14 to 1.29 ± 0.28 μL/min/g in rats, and rovatirelin was stable in rat plasma and brain homogenates.</p> <p>3.The metabolite pattern was qualitatively similar <i>in vitro</i> and <i>in vivo.</i> In animals, rovatirelin aminopentanoic acid (rovatirelin-acid), rovatirelin aminopentanone (rovatirelin-ketone), rovatirelin pyrrolidine (4S)-hydroxy (rovatirelin-OH), (thiazoylalanyl)methylpyrrolidine (TAMP), 3-(4-thiazoyl)-l-alanine (TA), and unknown metabolites were observed. In human hepatocytes, TAMP was mainly formed and no unique human metabolite was observed.</p> <p>4.The radioactivity from administered [¹⁴C]rovatirelin was predominantly excreted in faeces in rats and dogs, and almost all radioactivity was recovered 168 h after administration. Absorption, brain penetration, and stability of rovatirelin in the brain were greater than for taltirelin.</p> <p>5.Thus, orally administered rovatirelin is a potentially improved treatment for spinocerebellar degeneration compared with taltirelin.</p

High-throughput assay to simultaneously evaluate activation of CYP3A and the direct and time-dependent inhibition of CYP3A, CYP2C9, and CYP2D6 using liquid chromatography-tandem mass spectrometry

In the early stages of drug discovery, adequate evaluation of the potential drug–drug interactions (DDIs) of drug candidates is important. Several CYP3A activators are known to lead to underestimation of DDIs. These compounds affect midazolam 1'-hydroxylation but not midazolam 4-hydroxylation.We used both metabolic reactions of midazolam to evaluate the activation and inhibition of CYP3A activators simultaneously. For our CYP inhibition assay using cocktail probe substrates, simultaneous liquid chromatography-tandem mass spectrometry monitoring of 1'-hydroxymidazolam and 4-hydroxymidazolam for CYP3A was established in addition to monitoring of 4-hydroxydiclofenac and 1'-hydroxybufuralol for CYP2C9 and CYP2D6.The results of our cocktail inhibition assay were well correlated with those of a single inhibition assay, as were the estimated inhibition parameters for typical CYP3A inhibitors. In our assay, a proprietary compound that activated midazolam 1'-hydroxylation and tended to inhibit 4-hydroxylation was evaluated along with known CYP3A activators. All compounds were well characterised by comparison of the results of midazolam 1'- and 4-hydroxylation.In conclusion, our CYP cocktail inhibition assay can detect CYP3A activation and assess the direct and time-dependent inhibition potentials for CYP3A, CYP2C9, and CYP2D6. This method is expected to be very efficient in the early stages of drug discovery. In the early stages of drug discovery, adequate evaluation of the potential drug–drug interactions (DDIs) of drug candidates is important. Several CYP3A activators are known to lead to underestimation of DDIs. These compounds affect midazolam 1'-hydroxylation but not midazolam 4-hydroxylation. We used both metabolic reactions of midazolam to evaluate the activation and inhibition of CYP3A activators simultaneously. For our CYP inhibition assay using cocktail probe substrates, simultaneous liquid chromatography-tandem mass spectrometry monitoring of 1'-hydroxymidazolam and 4-hydroxymidazolam for CYP3A was established in addition to monitoring of 4-hydroxydiclofenac and 1'-hydroxybufuralol for CYP2C9 and CYP2D6. The results of our cocktail inhibition assay were well correlated with those of a single inhibition assay, as were the estimated inhibition parameters for typical CYP3A inhibitors. In our assay, a proprietary compound that activated midazolam 1'-hydroxylation and tended to inhibit 4-hydroxylation was evaluated along with known CYP3A activators. All compounds were well characterised by comparison of the results of midazolam 1'- and 4-hydroxylation. In conclusion, our CYP cocktail inhibition assay can detect CYP3A activation and assess the direct and time-dependent inhibition potentials for CYP3A, CYP2C9, and CYP2D6. This method is expected to be very efficient in the early stages of drug discovery.</p

Dynamic Kinetic Resolution of N‑Protected Amino Acid Esters via Phase-Transfer Catalytic Base Hydrolysis

Asymmetric base hydrolysis of α-chiral esters with synthetic small-molecule catalysts is described. Quaternary ammonium salts derived from quinine were used as chiral phase-transfer catalysts to promote the base hydrolysis of N-protected amino acid hexafluoroisopropyl esters in a CHCl₃/NaOH (aq) via dynamic kinetic resolution, providing the corresponding products in moderate to good yields (up to 99%) with up to 96:4 er. Experimental and computational mechanistic studies using DFT calculation and pseudotransition state (pseudo-TS) conformational search afforded a TS model accounting for the origin of the stereoselectivity. The model suggested π-stacking and H-bonding interactions play essential roles in stabilizing the TS structures

Indirect activation of pregnane X receptor in the induction of hepatic CYP3A11 by high-dose rifampicin in mice

<p>Rifampicin (RIF), a typical ligand of human pregnane X receptor (PXR), powerfully induces the expression of cytochrome P450 3A4 (CYP3A4) in humans. Although it is thought that RIF is not a ligand of rodent PXR, treatment with high-dose RIF (e.g. more than 20 mg/kg) increases the expression of CYP3A in the mouse liver. In this study, we investigated whether the induction of CYP3A by high-dose RIF in the mouse liver is mediated <i>via</i> indirect activation of mouse PXR (mPXR). The results showed that high-dose RIF increased the expression of CYP3A11 and other PXR-target genes in the liver of wild-type mice but not PXR-knockout mice. However, the results of reporter gene and ligand-dependent assembly assays showed that RIF does not activate mPXR in a ligand-dependent manner. In addition, high-dose RIF stimulated nuclear accumulation of mPXR in the mouse liver, and geldanamycin and okadaic acid attenuated the induction of <i>Cyp3a11</i> and other PXR-target genes in primary hepatocytes, suggesting that high-dose RIF triggers nuclear translocation of mPXR. In conclusion, the present study suggests that high-dose RIF stimulates nuclear translocation of mPXR in the liver of mice by indirect activation, resulting in the transactivation of <i>Cyp3a11</i> and other PXR-target genes.</p

List of cervical cancer-related disease groups and control groups.

<p>List of cervical cancer-related disease groups and control groups.</p

Change in HPV-16/-18 Ab levels after vaccination.

<p><b>A.</b> A schema of the vaccination and blood sampling protocol. HPV vaccination (Gardasil^®) was provided at 0, 2, and 6 months, and blood sampling was conducted at 0 (pre), 6 (1st), and 18 (2nd) months. <b>B and C.</b> The change in serum HPV-16 (left) and HPV-18 (right) Ab concentrations of each subject was observed at the 1st and 2nd time-point. Asterisk (*) represents p < 0.001, one-way ANOVA. <b>D</b> and <b>E</b>. Correlation between anti-HPV-16 Ab (x-axis) and anti-HPV-18 Ab (y-axis) at 1st (6 months, left) and at 2nd (18 months, right) collection time points.</p

Correlation between IC and MB-ELISA.

<p><b>A.</b> Technical details of IC method to visualize L1 Abs. IC values are given as a visual score, determined by the color chart. (C, control line; T, test line). <b>B and C</b>. Scatter plots of IC (x-axis) and MB-ELISA (y-axis) from the same samples for anti-HPV-16 and HPV-18 Ab levels. <b>B.</b> The same samples in <b><a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0171314#pone.0171314.g002" target="_blank">Fig 2</a></b> were measured by IC. <b>C.</b> The same samples in <b><a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0171314#pone.0171314.g003" target="_blank">Fig 3</a></b> were measured by IC. Five samples were arbitrarily selected from each group. Appearance of IC results were shown in <b><a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0171314#pone.0171314.s003" target="_blank">S3 Fig</a></b>.</p

Preparing HPV-16L1/-18L1 antigens and their immunoreactivities.

<p><b>A.</b> HPV-16 L1/HPV-18 L1 recombinant proteins obtained in this study were detected by western blot. In all membranes, line 1: Dock-Tag purified pupae infected with HPV-16 L1, line 2: Dock-Tag purified pupae infected with HPV-18 L1, line 3: non-infection pupae, and line 4: non-recombination viral infection pupae. <b>B.</b> Purified HPV-16 L1/HPV-18 L1 recombinant proteins or Cervarix^® were captured on plates with 25, 10, 5 ng as antigens and direct ELISA was performed. Cervarix^® contains HPV-16/-18 VLP and was used as a positive control. As a primary Ab, antisera of rabbit #1 (black bar) and rabbit #2 (gray bar) were used. <b>C.</b> Direct ELISA results showed HPV type-specific immunoreactivities with relatively high backgrounds by measuring with the international standard serum for HPV-16 and HPV-18. We used a control serum that was negative to HPV Ags by validation using ELISA with Cervarix^® Ag (<b><a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0171314#pone.0171314.s002" target="_blank">S2 Fig</a></b>). ELISA was performed twice independently in triplicate. Asterisk (*) indicates a significant difference from the control serum (<i>p</i> < 0.05). <b>D.</b> MB-ELISA showed higher type-specific immunoreactivity than the direct ELISA. Values are means of triplicate results, and error bars show standard deviations.</p

List of vaccines and time-course sample collection.

<p>List of vaccines and time-course sample collection.</p