A phase 2, randomized, double‐blind, placebo‐controlled study of GS‐9450 in subjects with nonalcoholic steatohepatitis

In nonalcoholic steatohepatitis (NASH), the extent of hepatocyte apoptosis correlates with disease severity. Reducing hepatocyte apoptosis with the selective caspase inhibitor GS‐9450 has a potential for altering the course of the liver disease. In this phase 2, double‐blind study, 124 subjects with biopsy‐proven NASH were randomized to once‐daily placebo or 1, 5, 10, or 40 mg GS‐9450 for 4 weeks. Absolute and percent changes from baseline in ALT levels, AST levels, and caspase‐3–cleaved cytokeratin (CK)‐18 fragments at week 4 were assessed by an analysis of covariance model with adjustment for baseline values. In the 40‐mg group, mean (SD) ALT decreased by 47 (43) U/L from baseline to week 4 ( P < 0.0001 versus placebo), and the proportion of subjects with normal ALT increased from 0% to 35% at week 4. In the 40‐mg group, mean AST decreased by 13 U/L from baseline (not significant), and the proportion with normal AST increased from 20% at baseline to 48% at week 4. By week 4, mean CK‐18 fragment levels had decreased to 393 (723) U/L in the GS‐9450 10‐mg group and 125 (212) U/L in the 40‐mg group, but these reductions were not statistically significant. No serious adverse events were reported during treatment, and the percentage of subjects with at least one treatment‐emergent grade 3 or 4 laboratory abnormality ranged from 11.5% to 17% across the GS‐9450 treatment groups versus 35% in the placebo group. Conclusion : GS‐9450 treatment induced significant reductions in ALT levels in NASH patients. Reductions in CK‐18 fragment levels also occurred, although they were not statistically significant. At appropriate therapeutic indices, selective caspase inhibitors may be a promising treatment option in patients with NASH. (H epatology 2012)Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/90118/1/24747_ftp.pd

Low-Spin Heme b3 in the Catalytic Center of Nitric Oxide Reductase from Pseudomonas nautica

Biochemistry, 2011, 50 (20), pp 4251–4262 DOI: 10.1021/bi101605pRespiratory nitric oxide reductase (NOR) was purified from membrane extract of Pseudomonas (Ps.) nautica cells to homogeneity as judged by polyacrylamide gel electrophoresis. The purified protein is a heterodimer with subunits of molecular masses of 54 and 18 kDa. The gene encoding both subunits was cloned and sequenced. The amino acid sequence shows strong homology with enzymes of the cNOR class. Iron/heme determinations show that one heme c is present in the small subunit (NORC) and that approximately two heme b and one non-heme iron are associated with the large subunit (NORB), in agreement with the available data for enzymes of the cNOR class. Mössbauer characterization of the as-purified, ascorbate-reduced, and dithionite-reduced enzyme confirms the presence of three heme groups (the catalytic heme b(3) and the electron transfer heme b and heme c) and one redox-active non-heme Fe (Fe(B)). Consistent with results obtained for other cNORs, heme c and heme b in Ps. nautica cNOR were found to be low-spin while Fe(B) was found to be high-spin. Unexpectedly, as opposed to the presumed high-spin state for heme b(3), the Mössbauer data demonstrate unambiguously that heme b(3) is, in fact, low-spin in both ferric and ferrous states, suggesting that heme b(3) is six-coordinated regardless of its oxidation state. EPR spectroscopic measurements of the as-purified enzyme show resonances at the g ∼ 6 and g ∼ 2-3 regions very similar to those reported previously for other cNORs. The signals at g = 3.60, 2.99, 2.26, and 1.43 are attributed to the two charge-transfer low-spin ferric heme c and heme b. Previously, resonances at the g ∼ 6 region were assigned to a small quantity of uncoupled high-spin Fe(III) heme b(3). This assignment is now questionable because heme b(3) is low-spin. On the basis of our spectroscopic data, we argue that the g = 6.34 signal is likely arising from a spin-spin coupled binuclear center comprising the low-spin Fe(III) heme b(3) and the high-spin Fe(B)(III). Activity assays performed under various reducing conditions indicate that heme b(3) has to be reduced for the enzyme to be active. But, from an energetic point of view, the formation of a ferrous heme-NO as an initial reaction intermediate for NO reduction is disfavored because heme [FeNO](7) is a stable product. We suspect that the presence of a sixth ligand in the Fe(II)-heme b(3) may weaken its affinity for NO and thus promotes, in the first catalytic step, binding of NO at the Fe(B)(II) site. The function of heme b(3) would then be to orient the Fe(B)-bound NO molecules for the formation of the N-N bond and to provide reducing equivalents for NO reduction

Scientific Opinion on the evaluation of the substances currently on the list in the annex to Commission Directive 96/3/EC as acceptable previous cargoes for edible fats and oils – Part III of III

Shipping of edible fats and oils into Europe is permitted in bulk tanks, in which substances, included in a positive list, had been previously transported. The European Commission requested EFSA to evaluate the list of substances in the Annex to Commission Directive 96/3/EC as acceptable previous cargoes for edible fats and oils, taking into account its review of the Scientific Committee on Food criteria for acceptable previous cargoes and criteria proposed by the Codex Committee for Fats and Oils. This is the third and last scientific opinion of the EFSA Panel on Contaminants in the Food Chain (CONTAM Panel) on this topic, in which sixteen of these substances or groups of substances have been evaluated. The CONTAM Panel concluded that sodium silicate (water glass) solution, iso-octanol, iso-nonanol, iso-decanol, 1,3-propanediol, isobutyl acetate, sec-butyl acetate, tert-butyl acetate, n-butyl acetate, propylene tetramer, paraffin wax, candelilla wax, white mineral oils and glycerol would not be of health concern as previous cargoes. The CONTAM Panel concluded that carnauba wax was not acceptable as a previous cargo because of its insolubility in water and high melting point, which raise concerns regarding the efficiency of tank cleaning. There was insufficient information available on the composition of montan wax for the CONTAM Panel to conclude that it would be of no health concern when used as previous cargo and hence it does not meet the criteria for acceptability as previous cargo. The CONTAM Panel made several recommendations regarding the way in which the substances are described in the Annex to Commission Directive 96/3/EC, to correct inaccuracies and to better reflect current transport practices

Charles I: Unhero of Royalist Poetry

During the English Civil War, Charles I appeared as a character in Royalist poetry, both directly and allegorically. These depictions drew on ancient Roman epic poems, particularly Lucan’s De Bello Civili, in their treatment of the subject matter of civil war and Charles as an epic hero. Though the authors of these poems supported Charles, their depictions of him and his reign reveal anxiety about his weakness as a ruler. In comparison to the cults of personality surrounding his predecessors and the heroes of De Bello Civili, his cult appears bland and forced. The lack of enthusiasm surrounding Charles I may help to explain his downfall at the hands of his Parliamentarian opponents.

Synthetic methods and studies of some 10-Y-5 and 12-Y-6 hypervalent main group element species of group IIIB

p-t-Butylhexafluorocumylthiol and N,N-dimethylhexafluorocumylamine were synthesized and found not to undergo ortho-lithiation. p-t-Butylhexafluorocumylthiol forms several products upon treatment with an alkyllithium reagent and N,N-dimethylhexafluorocumylamine undergoes meta-lithiation upon treatment with sec-butyllithium in the presence of TMEDA. Evidence for the formation of stable hypervalent phosphorus and silicon species using 1,3-bis(2\sp\prime-pyridylimino)isoindoline as a tridentate ligand was obtained.New synthetic routes were developed for 4-t-butyl-2,6-bis(1-hydroxy-1-trifluoromethyl-2,2,2-trifluoroethyl)pyridine and 2-amino-4-(t-butyl)pyridine which allowed their synthesis on a large scale, with reasonable amounts formed. The former was synthesized by ortho-lithiation of 4-t-butyl-2-(1-hydroxy-1-trifluoromethyl-2,2,2-trifluoroethyl)-pyridine-1-oxide and treatment with hexafluoroacetone. The latter was synthesized by nucleophilic aromatic substitution on 2-bromo-4-t-butylpyridine using sodium amide as nucleophile.Because a new melting point reflecting a new crystal structure for 10-t-butyl-1-chloro-3,3,7,7-tetrakis(trifluoromethyl)-4,6-benzo-5-azonia-1-borata-2,8-dioxabicyclo- (3,3,0) octane resulted in a change in solubility and reactivity, new routes to hypervalent 12-B-6 and 10-B-5 species were explored, and were not successful.N,N,N-tributylbutanaminium(OC-6-11\sp\prime)-bis (4-(1,1-dimethylethyl)-\alpha,\alpha,\alpha\sp\prime\alpha\sp\prime-tetrakis(trifluoromethyl)-2,6-pyridinedimethanolato(2-)N1,O$\alpha$,O\alpha\sp\prime) aluminum, a 12-Al-6 anionic species was synthesized and experimentally examined. Neutral mono-protonated and mono-methylated products of this anion were synthesized and studied. X-ray crystallography was used to establish the structure of the octahedral 12-Al-6 species and its protonated analogue. The protonated species was a distorted octahedral species with the proton hydrogen-bonding two of the apical oxygens.U of I OnlyETDs are only available to UIUC Users without author permissio

Sodium Nitrite-Mediated Killing of the Major Cystic Fibrosis Pathogens Pseudomonas aeruginosa, Staphylococcus aureus, and Burkholderia cepacia under Anaerobic Planktonic and Biofilm Conditions▿

A hallmark of airways in patients with cystic fibrosis (CF) is highly refractory, chronic infections by several opportunistic bacterial pathogens. A recent study demonstrated that acidified sodium nitrite (A-NO2−) killed the highly refractory mucoid form of Pseudomonas aeruginosa, a pathogen that significantly compromises lung function in CF patients (S. S. Yoon et al., J. Clin. Invest. 116:436-446, 2006). Therefore, the microbicidal activity of A-NO2− (pH 6.5) against the following three major CF pathogens was assessed: P. aeruginosa (a mucoid, mucA22 mutant and a sequenced nonmucoid strain, PAO1), Staphylococcus aureus USA300 (methicillin resistant), and Burkholderia cepacia, a notoriously antibiotic-resistant organism. Under planktonic, anaerobic conditions, growth of all strains except for P. aeruginosa PAO1 was inhibited by 7.24 mM (512 μg ml−1 NO2−). B. cepacia was particularly sensitive to low concentrations of A-NO2− (1.81 mM) under planktonic conditions. In antibiotic-resistant communities known as biofilms, which are reminiscent of end-stage CF airway disease, A-NO2− killed mucoid P. aeruginosa, S. aureus, and B. cepacia; 1 to 2 logs of cells were killed after a 2-day incubation with a single dose of ∼15 mM A-NO2−. Animal toxicology and phase I human trials indicate that these bactericidal levels of A-NO2− can be easily attained by aerosolization. Thus, in summary, we demonstrate that A-NO2− is very effective at killing these important CF pathogens and could be effective in other infectious settings, particularly under anaerobic conditions where bacterial defenses against the reduction product of A-NO2−, nitric oxide (NO), are dramatically reduced