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Correction: 10.1021/acs.joc.1c02513. The tear film lipid layer (TFLL) that covers the ocular surface contains several unique lipid classes, including O-acyl-omega-hydroxy fatty acids, type I-St diesters, and type II diesters. While the TFLL represents a unique biological barrier that plays a central role in stabilizing the entire tear film, little is known about the properties and roles of individual lipid species. This is because their isolation from tear samples in sufficient quantities is a tedious task. To provide access to these species in their pure form, and to shed light on their properties, we here report a general strategy for the synthesis and structural characterization of these lipid classes. In addition, we study the organization and behavior of the lipids at the air-tear interface. Through these studies, new insights on the relationship between structural features, such as number of double bonds and the chain length, and film properties, such as spreading and evaporation resistance, were uncovered.

Aluminium oxide and gallium oxide nanorods were identified as highly efficient heterogeneous catalysts for the selective oxidation of aromatic amines to azoxy compounds using hydrogen peroxide as environmentally friendly oxidant. This is the first report of the selective oxidation of aromatic amines to their azoxy derivatives without using transition metal catalysts. Among the tested transition-metal-free oxides, gallium oxide nanorods with small dimensions (9-52 nm length and 3-5 nm width) and fully accessible, high surface area (225 m(2) g(-1)) displayed the best catalytic performance in terms of substrate versatility, activity and azoxybenzene selectivity. Furthermore, the catalyst loading, hydrogen peroxide type (aqueous or anhydrous), and the amount of solvent were tuned to optimise the catalytic performance, which allowed reaching almost full selectivity (98 %) towards azoxybenzene at high aniline conversion (94 %). Reusability tests showed that the gallium oxide nanorod catalyst can be recycled in consecutive runs with complete retention of the original activity and selectivity.

Although the vast majority of women encounters at least one vaginal infection during their life, the amount of microbiome-related research performed in this area lags behind compared to alternative niches such as the intestinal tract. As a result, effective means of diagnosis and treatment, especially of recurrent infections, are limited. The role of the metabolome in vaginal health is largely elusive. It has been shown that lactate produced by the numerous lactobacilli present promotes health by limiting the chance of infection. Short chain fatty acids (SCFA) have been mainly linked to dysbiosis, although the causality of this relationship is still under debate. In this review, we aim to bring together information on the role of the vaginal metabolome and microbiome in infections caused by Candida. Vulvovaginal candidiasis affects near to 70% of all women at least once in their life with a significant proportion of women suffering from the recurrent variant. We assess the role of fatty acid metabolites, mainly SCFA and lactate, in onset of infection and virulence of the fungal pathogen. In addition, we pinpoint where lack of research limits our understanding of the molecular processes involved and restricts the possibility of developing novel treatment strategies. ispartof: FRONTIERS IN MICROBIOLOGY vol:12 ispartof: location:Switzerland status: published

BACKGROUND: Cholesterol Efflux Capacity (CEC) is considered to be a key atheroprotective property of high-density lipoproteins (HDL). However, the role of HDL-CEC in atherosclerosis and cardiovascular (CV) risk is still controversial, and data in individuals with diabetes are limited.OBJECTIVE: In this study, we have investigated the relationship of CEC and other HDL characteristics with clinical and subclinical atherosclerosis in subjects with elevated cardiovascular diseases (CVD) risk and Type 2 Diabetes Mellitus (T2DM).METHODS: Using multiple linear regression analyses, we determined the relationship of HDL-CEC with carotid intima-media thickness (cIMT, Z-Score), an endothelial dysfunction (EnD) Score (Z-Score), prevalent CVD (n = 150 cases) and history of CV events (CVE, n = 85 cases) in an observational cohort (CODAM, n = 574, 59.6 ± 0.3 yr, 61.3% men, 24.4% T2DM). Stratified analyses were performed to determine if the associations differed between individuals with normal glucose metabolism (NGM) and those with disturbed glucose metabolism.RESULTS: HDL-CEC was not associated with either marker of atherosclerosis (cIMT, EnD Score) nor with CVD or CVE. In contrast, other HDL characteristics that is, HDL-Cholesterol (HDL-C, Z-Score), apolipoprotein A-I (apoA-I, Z-Score), HDL size (Z-Score) and HDL particle number (HDL-P, Z-Score) were inversely and significantly associated with the EnD Score (s -0.226 to -0.097, P < .05) and CVE (ORs 0.61 to 0.68, P < .05). In stratified analyses, HDL size and HDL-P were significantly associated with the EnD Score in individuals with NGM (Pinteraction .039 and .005, respectively), but not in those with (pre)diabetes. HDL-C and apoA-I were inversely associated with prevalent CVD in individuals with (pre)diabetes (Pinteraction = .074 and .034, respectively), but not in those with NGM.CONCLUSION: HDL-CEC is not associated with clinical or subclinical atherosclerosis, neither in the whole population nor in individuals with (pre)diabetes, while other HDL characteristics show atheroprotective associations. The atheroprotective associations of HDL-size and HDL-P are lost in (pre)diabetes, while higher concentrations of HDL-C and apoA-I are associated with a lower prevalence of CVD in (pre)diabetes.

Catalyst deactivation due to coking is a major challenge in the catalytic fast pyrolysis (CFP) of biomass. Here, a multitechnique investigation of a technical Al2O3-bound ZSM-5-based extrudate catalyst, used for the CFP of pine wood and cellulose (at a reactor temperature of 500 °C), provided insight into the effects of extrusion, the catalytic pyrolysis process, and catalyst regeneration on the catalyst structure. As a result of a reduction in acidity and surface area due to the coking catalyst, the activity dropped drastically with increasing time-on-stream (TOS), as evidenced by a decrease in aromatics yield. Strikingly, confocal fluorescence microscopy at the single-particle level revealed that vapor components derived from whole biomass or just the cellulose component coke differently. While pine-wood-derived species mainly blocked the external area of the catalyst particle, larger carbon deposits were formed inside the catalyst's micropores with cellulose-derived species. Pyridine FT-IR and solid-state NMR spectroscopy demonstrated irreversible changes after regeneration, likely due to partial dealumination. Taken together with

A solvometallurgical process for the separation of indium(iii) and zinc(ii) from ethylene glycol solutions using the ionic liquid extractants Cyphos IL 101 and Aliquat 336 in an aromatic diluent has been investigated. The speciation of indium(iii) in the two immiscible organic phases was investigated by Raman spectroscopy, infrared spectroscopy, EXAFS and 115In NMR spectroscopy. At low LiCl concentrations in ethylene glycol, the bridging (InCl3)2(EG)3 or mononuclear (InCl3)(EG)2 complex is proposed. At higher lithium chloride concentrations, the first coordination sphere changes to two oxygen atoms from one bidentate ethylene glycol ligand and four chloride anions ([In(EG)Cl4]-). In the less polar phase, indium(iii) is present as a tetrahedral [InCl4]- complex independent of the LiCl concentration. After the number of theoretical stages had been determined using a McCabe-Thiele diagram for extraction by Cyphos IL 101, the extraction and scrubbing processes were performed in lab-scale mixer-settlers to test the feasibility of working in continuous mode. Indium(iii) was extracted quantitatively in four stages, with 19% co-extraction of zinc(ii). The co-extracted zinc(ii) was scrubbed selectively in six stages using an indium(iii) scrub solution. Indium(iii) was recovered from the loaded less polar organic phase as indium(iii) hydroxide (98.5%) by precipitation stripping with an aqueous NaOH solution. ispartof: RSC ADVANCES vol:10 issue:41 pages:24595-24612 ispartof: location:England status: published

The joint consensus panel of the European Atherosclerosis Society (EAS) and the European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) recently addressed present and future challenges in the laboratory diagnostics of atherogenic lipoproteins. Total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDLC), LDL cholesterol (LDLC), and calculated non-HDLC (=total – HDLC) constitute the primary lipid panel for estimating risk of atherosclerotic cardiovascular disease (ASCVD) and can be measured in the nonfasting state. LDLC is the primary target of lipid-lowering therapies. For on-treatment follow-up, LDLC shall be measured or calculated by the same method to attenuate errors in treatment decisions due to marked between-method variations. Lipoprotein(a) [Lp(a)]-cholesterol is part of measured or calculated LDLC and should be estimated at least once in all patients at risk of ASCVD, especially in those whose LDLC declines poorly upon statin treatment. Residual risk of ASCVD even under optimal LDL-lowering treatment should be also assessed by non-HDLC or apolipoprotein B (apoB), especially in patients with mild-to-moderate hypertriglyceridemia (2–10 mmol/L). Non-HDLC includes the assessment of remnant lipoprotein cholesterol and shall be reported in all standard lipid panels. Additional apoB measurement can detect elevated LDL particle (LDLP) numbers often unidentified on the basis of LDLC alone. Reference intervals of lipids, lipoproteins, and apolipoproteins are reported for European men and women aged 20–100 years. However, laboratories shall flag abnormal lipid values with reference to therapeutic decision thresholds.

The Gd(iii)-complexes of three novel HP-DO3A-like ligands have been investigated to assess the relationship between relaxometry and intramolecular catalysis of the proton exchange. The structures of these ligands differ from the parent HP-DO3A because the methyl group of the hydroxy-propyl arm has been replaced by -Ph-OH, -Ph-NH2 and -Ph-COOH, respectively. The phenol, amine and carboxylate functionalities display an intramolecular H-bonding with the coordinated hydroxyl moiety that affects either the pK values of the involved functionalities and the rate of the proton exchange process.

To valorize oleaginous Schizochytrium sp. biomass, a novel sequential process was addressed and developed to simultaneously produce high value DHA-enriched glycerides and low value bulky biodiesels. In this process, Schizochytrium sp. biomass was first treated by alkaline protease; then the resulting biomass was directly subjected to enzymatic ethanolysis catalyzed by liquid enzymes from C. antarctica (CALA), T. lanuginosus (TL), R. miehei (RM) and A. oryzae (PLA). For all four liquid lipases, the alkaline protease treatment on Schizochytrium sp. biomass significantly enhanced total lipid recovery, biodiesel yield and yield of DHA-enriched glycerides. Under optimized conditions, CALA and TL achieved the highest biodiesel yields 76.28–76.66 wt% based on microalgae TFAs while PLA had the lowest (55.25 wt%). Moreover, CALA attained the highest DHA (77.93 wt%) and LC PUFAs (93.08 wt%) contents in glyceride fraction, suggesting a superior performance to concentrate DHA and LC PUFAs in glycerides. 13 C NMR analysis illustrated that non-regiospecificity and unfavorability towards LC PUFAs of CALA made it possible to transesterify saturated fatty acids located in all 3 positions of microalgal oil; thus LC PUFAs were highly enriched in glycerides. Overall, the sequential process using enzymes and ethanol as green media was successfully established for the co-production of high-value microalgal bioproducts rich in LC PUFAs and sustainable biodiesels in a comprehensive manner.

Two PDMS-SiO2-TiO2-Cao porous hybrid materials were prepared using the same base composition, precursors, and solvents, but following two different sol-gel procedures, based on the authors' previous works where for the first time, in this hybrid system, calcium acetate was used as calcium source. The two different procedures resulted in monolithic materials with different structures, microstructures, and surface wettability. Even though both are highly hydrophobic (contact angles of 127.2 degrees and 150.6 degrees), and present different filling regimes due to different surface topographies, they have demonstrated to be-cytocompatible when tested with human osteoblastic cells, against the accepted idea that high-hydrophobic surfaces are not suitable to cell adhesion and proliferation. At the nanoscale, the existence of hydrophilic silica domains containing calcium, where water molecules are physisorbed, is assumed to support this capability, as discussed. (C) 2016 Elsevier B.V. All rights reserved.

We report an extensive 600 MHz NMR trial of a quantitative lipoprotein and small molecule measurements in human blood serum and plasma. Five centers with eleven 600 MHz NMR spectrometers were used to analyze 98 samples including: 20 QCs, 37 commercially sourced, paired serum and plasma samples and 2 National Institute of Science and Technology, NIST, reference material 1951c replicates. Samples were analyzed using rigorous protocols for sample preparation and experimental acquisition. A commercial lipoprotein subclass analysis was used to quantify 105 lipoprotein subclasses and 24 low molecular weight metabolites from the nuclear magnetic resonance, NMR, spectra. For all spectrometers, the instrument specific variance in measuring internal quality controls, QCs, was lower than the percentage described by the National Cholesterol Education Program, NCEP, criteria for lipid testing (triglycerides

The new compounds Rbpy)(2)Os-II(mu-L-1(2-))Os-II(bpy)(2)](ClO4)(2) ([1]-(ClO4)(2)) and [(pap)(2)Os-II(mu-L,2)Os-II(pap)(2)] (ClO4)(2) ([2](ClO4)(2)) (H(2)L1 = 1,4dihydroxy-9,10-anthraquinone, bpy = 2,2/-bipyridine, and pap = 2-phenylazopyridine) and Rbpy)(2)Os-II(mu-L-2(center dot-))Os-II(bpy)(2)] (ClO4)(3) ([3] (ClO4)(3)) and Rpap)(2)Os-II(itL22-)Os-11(pap)(2)] (ClO4)(2) ([4] (ClO4)(2)) (H2L2 = 1,4-diamino-9,10-anthraquinone) have been analytically identified as the meso and rac diastereoisomers, respectively. The paramagnetic [3] (ClO4)(3) was also characterized by crystal structure determination. In CD3CN solution, [3] (ClO4)(3) displays rather narrow but widely split (13 > 5> 8 ppm) resonances in the 11-1 NMR spectrum, yet no EPR signal was observed down to 120 K Cyclic voltammetry and differential pulse voltammetry reveal several accessible redox states on oxidation and reduction, showing that the replacement of 1,4-oxido by imido donors causes cathodic shifts and that the substitution of bpy by the stronger 2T-accept ng pap ligands leads to a strong increase of redox potentials. Accordingly, system 3" with the lowest (2+13+) potential was synthetically obtained in the mono-oxidized (3+) form. The (3+) intermediates display small comproportionation constants lc of about 103 and long-wavelength near-infrared absorptions; an EPR signal with appreciable g splitting (1.84, 1.96, and 2.03) was only observed for 43+, which exhibits the smallest spin density on the osmium centers. An oxidation state formulation [Os-III(y1.73-)Os-III]3+ with some [Osii(mu-L2-)Os3+ contribution was found to best describe the electronic structures. UV-vis NIR absorption spectra were recorded for all accessible states by OTTLE spectroelectrochemistry and assigned on the basis of TDDFT calculations. These results and additional EPR measurements suggest rather variegated oxidation state situations, e.g., the pap ligands competing with the bridge L for electrons, while the oxidation produces mixed spin systems with variable metal/ ligand contributions.

Specific synthetic routes are presented in schemes to illustrate the chemistry, and the analogs are presented in a table format to give an accessible overview of the structures. Several patents have been published regarding the properties of griseofulvin and its derivatives including synthesis, formulation, and their medicinal and agricultural applications. The antifungal mode-of-action of griseofulvin has been the subject of considerable research efforts and some debate over the years, a discussion that is still ongoing. Griseofulvin was one of the first antifungal natural products found in filamentous fungi. During the years, this polyketide has been found to be produced by several Ascomycetes including both closely and distantly related species.

Polyglutamine expansion in the huntingtin protein is the primary genetic cause of Huntington's disease (HD). Fragments coinciding with mutant huntingtin exon1 aggregate in vivo and induce HD-like pathology in mouse models. The resulting aggregates can have different structures that affect their biochemical behaviour and cytotoxic activity. Here we report our studies of the structure and functional characteristics of multiple mutant htt exon1 fibrils by complementary techniques, including infrared and solid-state NMR spectroscopies. Magic-angle-spinning NMR reveals that fibrillar exon1 has a partly mobile α-helix in its aggregation-accelerating N terminus, and semi-rigid polyproline II helices in the proline-rich flanking domain (PRD). The polyglutamine-proximal portions of these domains are immobilized and clustered, limiting access to aggregation-modulating antibodies. The polymorphic fibrils differ in their flanking domains rather than the polyglutamine amyloid structure. They are effective at seeding polyglutamine aggregation and exhibit cytotoxic effects when applied to neuronal cells., Huntington's disease is caused by a polyglutamine stretch expansion in the first exon of huntingtin. Here, the authors use infrared spectroscopy and solid-state NMR and show that polymorphic huntingtin exon1 fibres differ in their flanking regions but not their core polyglutamine amyloid structures.

The reaction of 2,2'-bipyridine-3,3'-diol (H2L) and cis-Os-II(bpy)(2)Cl-2 (bpy = 2,2'-bipyridine) results in isomeric forms of [Os-II(bpy)(2)(HL-)]ClO4, [1]ClO4 and [2]ClO4, because of the varying binding modes of partially deprotonated HL-. The identities of isomeric [1]ClO4 and [2]ClO4 have been authenticated by their single crystal X-ray structures. The ambidentate HL- in [2]ClO4 develops the usual N,N bonded five-membered chelate with a strong O-H center dot center dot center dot O hydrogen bonded situation (O-H center dot center dot center dot O angle: 160.78 degrees) at its back face. The isomer [1]ClO4 however represents the monoanionic O-,N coordinating mode of HL-, leading to a six-membered chelate with the moderately strong O-H center dot center dot center dot N hydrogen bonding interaction (O-H center dot center dot center dot N angle: 148.87 degrees) at its backbone. The isomeric [1]ClO4 and [2]ClO4 also exhibit distinctive spectral, electrochemical, electronic structural, and hydrogen bonding features. The pK(a) values for [1]ClO4 and [2]ClO4 have been estimated to be 0.73 and 50 degrees) in paramagnetic [Os-III(bpy)(2)(L'(2-))]ClO4 ([4]ClO4). The electronic structural aspects of the complexes reveal the noninnocent potential of the coordinated HL-, L2-, and L'(2-). The K-c value of 49 for 3(3+) reveals a class I mixed-valent (OsOsIII)-Os-II state.

We thank S. Mitani and O. Bossinger for slcf-1(tm2258) and OLB11 strains, respectively, and the C. elegans Genetics Center, which is funded by the NIH National Center for Research Resources, for other strains used in this work. We are grateful to S. Croze, N. Nazaret, and C. Rey from ProfileXpert, Genomique & Microgenomique, Universite Lyon 1, SFR sante LYON-EST, UCBL-INSERM US 7-CNRS UMS 3453 for gene expression analysis. We also thank Erin Rossini for carefully reading and correcting the manuscript; International audience; Dietary restriction (DR) is one of the most universal means of extending lifespan. Yet, whether and how DR specifically affects the metabolic changes associated with aging is essentially unknown. Here, we present a comprehensive and unbiased picture of the metabolic variations that take place with age at the whole organism level in Caenorhabditis elegans by using H-1 high-resolution magic-angle spinning (HR-MAS) nuclear magnetic resonance (NMR) analysis of intact worms. We investigate metabolic variations potentially important for lifespan regulation by comparing the metabolic fingerprint of two previously described genetic models of DR, the long-lived eat-2(ad465) and slcf1-(tm2258) worms, as single mutants or in combination with a genetic suppressor of their lifespan phenotype. Our analysis shows that significant changes in metabolite profiles precede the major physiological decline that accompanies aging and that DR protects from some of those metabolic changes. More specifically, low phosphocholine (PCho) correlates with high life expectancy. A mutation in the tumor suppressor gene PTEN/DAF-18, which suppresses the beneficial effects of DR in both C. elegans and mammals, increases both PCho level and choline kinase expression. Furthermore, we show that choline kinase function in the intestine can regulate lifespan. This study highlights the relevance of NMR metabolomic approaches for identifying potential biomarkers of aging

Objectives: We determined relationships of the anti-oxidative enzyme, paraoxonase-1 (PON-1), with high density lipoprotein (HDL) subfractions, and tested whether these relationships are stronger than those with HDL cholesterol and apolipoprotein A-I (apoA-I) in subjects with and without type 2 diabetes mellitus (T2DM).Design and methods: Serum PON-1 (arylesterase activity) and HDL subfractions (nuclear magnetic resonance spectroscopy) were determined in 67 T2DM patients and in 56 non-diabetic subjects.Results: PON-1 activity, HDL cholesterol and apoA-Iwere decreased in T2DM (all p Conclusions: PON-1 activity is more closely related to the HDL particle concentration or large HDL particles than to HDL cholesterol. Impaired PON-1 activity in T2DM is not to a considerable extent explained by altered HDL subfraction levels. (C) 2014 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Proto-cooperation between Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus is one of the key factors that determine the fermentation process and final quality of yoghurt. In this study, the interaction between different proteolytic strains of S. thermophilus and L. delbrueckii subsp. bulgaricus was investigated in terms of microbial growth, acidification and changes in the biochemical composition of milk during set-yoghurt fermentation. A complementary metabolomics approach was applied for global characterization of volatile and non-volatile polar metabolite profiles of yoghurt associated with proteolytic activity of the individual strains in the starter cultures. The results demonstrated that only non-proteolytic S. thermophilus (Prt −) strain performed proto-cooperation with L. delbrueckii subsp. bulgaricus. The proto-cooperation resulted in significant higher populations of the two species, faster milk acidification, significant abundance of aroma volatiles and non-volatile metabolites desirable for a good organoleptic quality of yoghurt. Headspace SPME-GC/MS and 1H NMR resulted in the identification of 35 volatiles and 43 non-volatile polar metabolites, respectively. Furthermore, multivariate statistical analysis allows discriminating set-yoghurts fermented by different types of starter cultures according to their metabolite profiles. Our finding underlines that selection of suitable strain combinations in yoghurt starters is important for achieving the best technological performance regarding the quality of product.

Water-based cellulose cholesteric liquid crystalline phases at rest can undergo structural changes induced by shear flow. This reflects on the deuterium spectra recorded when the system is investigated by rheo-nuclear magnetic resonance (rheo-NMR) techniques. In this work, the model system hydroxypropylcellulose (HPC)+water is revisited using rheo-NMR to clarify unsettled points regarding its behavior under shear and in relaxation. The NMR spectra allow the identification of five different stable ordering states, within shear and relaxation, which are well integrated in a mesoscopic picture of the system’s structural evolution under shear and relaxation. This picture emerging from the large body of studies available for this system by other experimental techniques, accounts well for the NMR data and is in good agreement with the three distinct regions of steady shear flow recognized for some lyotropic LC polymers. Shear rates in between 0.1 and 1.0 s–1 where investigated using a Taylor–Couette flow and de...

Graft copolymers of starch with acrylic acid are a promising green, bio based material with many potential applications. The grafting of acrylic acid onto cassava starch in an aqueous medium initiated by Fenton's reagent has been studied. Common grafting result parameters are add-on (yield) and graft efficiency (selectivity). However, the analysis of the reaction products and an accurate determination of these parameters stand or fall with a complete separation of the entangled but ungrafted homopolymer from the grafted product. Therefore, this separation is the core of the newly developed analytical procedure. An appropriate solvent has been selected with dedicated testing from the range methanol, ethanol, acetone, dioxane, 2-propanol, and 1-propanol. Acetone showed the best performance in many respects. It has a high dissolving power for the homopolymer, as well as the highest yield of precipitation for the starch derivatives and it is the most economical in use. After the successful separation, the precipitated graft copolymers could be analyzed quantitatively by nuclear magnetic resonance. The liquid with homopolymer and unreacted monomer was analyzed by high pressure liquid chromatography. Proof of grafting has been found by FTIR and TGA analyses. The mass balance calculation shows a systematic error which appears fairly consistent: 18.0 +/- 2.5 wt %. This was used as a correction factor in the calculation of the grafting parameters but more importantly, it means that the method we developed has a high level of repeatability, in the order of 97%. (C) 2013 Elsevier Ltd. All rights reserved.

In this study, the effect of torrefaction on the chemical and structural transformation of lignocellulosic biomass was investigated using complementary analytical tools. It was observed that the acid-insoluble fraction was increased from approximately 30 to 38% and the methoxyl content was decreased to about half after torrefaction at 330 °C for 2.5 min. These results highlight the formation of condensed structures along with lignin transformation via demethoxylation. Solid-state NMR spectroscopy indicated that upon torrefaction the aromaticity increased from about 36 to 60%. For the sample torrefied at 330 °C, the non-protonated aromatic carbon fraction was found to be about 60% of total aromatic carbons, indicating the formation of large aromatic clusters. The complementary analyses used in this study are proposed as a suitable approach for the elucidation of chemical and structural transformation of biomass during thermal treatment.

The previous work on the hydrolysis and alcoholysis reactions of phosphonium ylides is summarized and reviewed in the context of their currently accepted mechanisms. Several experimental facts relating to ylide hydrolysis and to salt and ylide alcoholysis are shown to conflict with those mechanisms. In particular, we demonstrate that the pK(a) values of water and alcohols are too high in organic media to bring about protonation of ylide. Therefore, we propose concerted addition of the water or alcohol O-H bond across the ylide P=C bond. In support of this, we provide NMR spectroscopic evidence for equilibrium between ylide and aclohol that does not require the involvement of phosphonium hydroxide. We report the first P-alkoxyphosphorane to be characterised by NMR spectroscopy that does not undergo exchange on an NMR timescale. Two-dimensional NMR spectroscopic techniques have been applied to the characterisation to P-alkoxyphosphoranes for the first time.

The unsymmetrical diruthenium complexes [(bpy)(2)Ru-II(mu-H2L2-)Ru-III(acac)(2)]ClO4 ([3]ClO4), [(pap)(2)Ru-II(mu-H2L2-)Ru-III(acac)(2)]ClO4 ([4]ClO4), and [(bpy)(2)Ru-II(mu-H2L2-)-Ru-II(pap)(2)](ClO4)(2) ([5](ClO4)(2)) have been obtained by way of the mononuclear precursors [(bpy)(2)Ru-II(H3L-)]ClO4 ([1]ClO4) and [(pap)(2)Ru-II(H3L-)]ClO4 ([2]ClO4) (where bpy = 2,2'-bipyridine, pap = 2-phenylazopyridine, acac(-) = 2,4-pentanedionate, and H4L = 1,4-diamino-9,10-anthraquinone). Structural characterization by single-crystal X-ray diffraction and magnetic resonance (nuclear magnetic resonance (NMR), electron paramagnetic resonance (EPR)) were used to establish the oxidation state situation in each of the isolated materials. Cyclic voltammetry, EPR, and ultraviolet-visible-near-infrared (UV-vis-NIR) spectroelectrochemistry were used to analyze the multielectron transfer series of the potentially class I mixed-valent dinuclear compounds, considering the redox activities of differently coordinated metals, of the noninnocent bridge and of the terminal ligands. Comparison with symmetrical analogues [L'Ru-2(mu-H2L)RuL'(2)](n) (where L' = bpy, pap, or acac(-)) shows that the redox processes in the unsymmetrical dinuclear compounds are not averaged, with respect to the corresponding symmetrical systems, because of intramolecular charge rearrangements involving the metals, the noninnocent bridge, and the ancillary ligands.

Significant advances in understanding aging have been achieved through studying model organisms with extended healthy lifespans. Employing 1H NMR spectroscopy, we characterized the plasma metabolic phenotype (metabotype) of three long-lived murine models: 30% dietary restricted (DR), insulin receptor substrate 1 null (Irs1–/–), and Ames dwarf (Prop1df/df). A panel of metabolic differences were generated for each model relative to their controls, and subsequently, the three long-lived models were compared to one another. Concentrations of mobile very low density lipoproteins, trimethylamine, and choline were significantly decreased in the plasma of all three models. Metabolites including glucose, choline, glycerophosphocholine, and various lipids were significantly reduced, while acetoacetate, d-3-hydroxybutyrate and trimethylamine-N-oxide levels were increased in DR compared to ad libitum fed controls. Plasma lipids and glycerophosphocholine were also decreased in Irs1–/– mice compared to controls, as were methionine and citrate. In contrast, high density lipoproteins and glycerophosphocholine were increased in Ames dwarf mice, as were methionine and citrate. Pairwise comparisons indicated that differences existed between the metabotypes of the different long-lived mice models. Irs1–/– mice, for example, had elevated glucose, acetate, acetone, and creatine but lower methionine relative to DR mice and Ames dwarfs. Our study identified several potential candidate biomarkers directionally altered across all three models that may be predictive of longevity but also identified differences in the metabolic signatures. This comparative approach suggests that the metabolic networks underlying lifespan extension may not be exactly the same for each model of longevity and is consistent with multifactorial control of the aging process.

The hydrogenation of phenylacetone to cyclohexylacetone, in which the aromatic ring is selectively reduced in preference to the carbonyl group, has been achieved with chemoselectivities exceeding 90%. The catalyst (precatalyst) used to achieve this transformation comprises PVP-stabilized Rh nanoparticles dispersed in water with some phosphine ligand additives. Phosphine ligands with different steric and electronic properties and polarities were investigated for this purpose, and several clear trends were observed, showing the potential of well-defined phosphine ligands as modifiers in nanocatalysis.

High-mass resolution multi-stage mass spectrometry (MS(n)) fragmentation was tested for differentiation and identification of metabolites, using a series of 121 polyphenolic molecules. The MS(n) fragmentation approach is based on the systematic breakdown of compounds, forming a so-called spectral tree. A chip-based nanoelectrospray ionization source was used combined with an ion-trap, providing reproducible fragmentation, and accurate mass read-out in an Orbitrap Fourier transform (FT) MS enabling rapid assignment of elemental formulas to the molecular ions and all fragment ions derived thereof. The used protocol resulted in reproducible MS(n) fragmentation trees up to MS(5). Obtained results were stable over a 5 month time period, a concentration change of 100-fold, and small changes in normalized collision energy, which is key to metabolite annotation and helpful in structure and substructure elucidation. Differences in the hydroxylation and methoxylation patterns of polyphenolic core structures were found to be reflected by the differential fragmentation of the entire molecule, while variation in a glycosylation site displayed reproducible differences in the relative intensities of fragments originating from the same aglycone fragment ion. Accurate MS(n)-based spectral tree data are therefore a powerful tool to distinguish metabolites with similar elemental formula, thereby assisting compound identification in complex biological samples such as crude plant extracts.

According to previous reports, Lactococcus lactis imports glucose via two distinct phosphoenolpyruvate: phosphotransferase systems (mannose-PTS and cellobiose-PTS) and one or more unknown non-PTS permease(s). GlcU was identified as the sole non-PTS permease involved in the transport of glucose. Additionally, the biochemical properties of PTS(Man), PTS(Cel) and GlcU were characterized in double knockout mutants with glucose uptake restricted to a single system. Transport susceptibility to protonophores indicated that glucose uptake via GlcU is proton-motive force dependent. Competition assays revealed a high specificity of GlcU for glucose. Furthermore, the permease has low affinity for glucose and displays strong preference for the beta-anomer as shown by the profiles of consumption of the two glucose anomers studied by (13)C-NMR. Similar kinetic properties were found for PTS(Cel), while PTS(Man) is a high-affinity system recognizing equally well the two anomeric forms of glucose. Transcripts of the genes encoding the three transporters are present simultaneously in the parent strain NZ9000 as shown by reverse transcription-PCR. Investigation of the distribution of GlcU homologues among bacteria showed that these proteins are restricted to the low-GC Gram-positive Firmicutes. This work completes the identification of the glucose transport systems in L. lactis MG1363.

Natural products chemistry has witnessed many new developments in the last 5 years like extractions with subcritical water and ionic liquids, LC/HRMS and LC/SPE/cryo-NMR, UHPLC, TLC/MS, MS-based preparative HPLC, comprehensive chromatography (GC × GC, LC × LC), high-throughput screening, introduction of monolithic columns, miniaturisation, and automated structure identification. Nevertheless identifying bioactive constituents in complex plant extracts remains a tedious process. The classical approach of bioassay guided fractionation is time-consuming while off-line screening of extracts does not provide information on individual compounds and sometimes suffers from false positives or negatives. One way out of this is by coupling chromatography with chemical or biochemical assays, so called high resolution screening. An example is the development of HPLC on-line assays for antioxidants. By the post-column addition of a relatively stable coloured radical like DPPH¿ or ABTS¿+, radical scavengers are detected as negative peaks because in a reaction coil they reduce the model radical to its reduced, non-coloured form. When combined with LC/DAD/MS and LC/SPE/NMR, reliable identification of active constituents becomes possible without the necessity of ever isolating them in a classical sense. Also for finding leads for new drugs, combining HPLC with biochemical assays is interesting but technically more difficult. Most enzymes do not work at the organic modifier concentrations commonly encountered in RP-HPLC and the reaction time is often longer requiring dilution and lengthy coils respectively. Therefore, new techniques have to be implemented to gain the required sensitivity for on-line enzyme assays. For stable analytes, high temperature LC offers a solution to the organic modifier problem. When enzymes are highly expensive, like those used in the screening for Cytochrome P450 inhibitors, miniaturisation to chip format may offer a way out. Microreactors (chips) are not only useful for miniaturising larger assays but also offer completely new prospects in phytochemical analysis. One such application is in the sample clean-up of acids and bases like alkaloids. In a lay-out of three parallel channels of 100 ¿m width with the middle one containing organic phase and the two outer ones water of high pH (feed phase) and low pH (trapping phase) such a chip replaces two classical LLE steps but is much faster and requires less solvents and less manpower input.

Streptococcus pneumoniae is a strictly fermentative human pathogen that relies on carbohydrate metabolism to generate energy for growth. The nasopharynx colonized by the bacterium is poor in free sugars, but mucosa lining glycans can provide a source of sugar. In blood and inflamed tissues glucose is the prevailing sugar. As a result during progression from colonization to disease S. pneumoniae has to cope with a pronounced shift in carbohydrate nature and availability. Thus, we set out to assess the pneumococcal response to sugars found in glycans and the influence of glucose (Glc) on this response at the transcriptional, physiological, and metabolic levels. Galactose (Gal), N-acetylglucosamine (GlcNAc), and mannose (Man) affected the expression of 8 to 14% of the genes covering cellular functions including central carbon metabolism and virulence. The pattern of end-products as monitored by in vivo (13)C-NMR is in good agreement with the fermentation profiles during growth, while the pools of phosphorylated metabolites are consistent with the type of fermentation observed (homolactic vs. mixed) and regulation at the metabolic level. Furthermore, the accumulation of α-Gal6P and Man6P indicate metabolic bottlenecks in the metabolism of Gal and Man, respectively. Glc added to cells actively metabolizing other sugar(s) was readily consumed and elicited a metabolic shift toward a homolactic profile. The transcriptional response to Glc was large (over 5% of the genome). In central carbon metabolism (most represented category), Glc exerted mostly negative regulation. The smallest response to Glc was observed on a sugar mix, suggesting that exposure to varied sugars improves the fitness of S. pneumoniae. The expression of virulence factors was negatively controlled by Glc in a sugar-dependent manner. Overall, our results shed new light on the link between carbohydrate metabolism, adaptation to host niches and virulence.

Plasma cholesteryl ester transfer (CET), reflecting transfer of cholesteryl esters from high density lipoproteins (HDL) towards apolipoprotein B-containing lipoproteins, may promote atherosclerosis development, and is elevated in Type 2 diabetes mellitus (T2DM). We determined the extent to which the relationship of plasma CET with very low density lipoprotein (VLDL) and low density lipoprotein (LDL) subfractions is modified in T2DM. Plasma CET, cholesteryl ester transfer protein (CETP) mass, as well as VLDL and LDL subfractions (nuclear magnetic resonance spectroscopy) were determined in 62 T2DM patients and 53 non-diabetic subjects. Plasma CET and CETP mass were increased in T2DM, coinciding higher triglycerides and large VLDL particles (all P 0.15). Abnormalities in the concentration and composition of large VLDL particles are likely to contribute to elevated plasma CET in T2DM. This article is protected by copyright. All rights reserved

Dinudear compounds [L2Ru(mu-E)RuL2](n) where L is acetylacetonate (acac(-), 2,4-pentanedionate), 2,2'-bipyridine (bpy), or 2-phenylazopyridine (pap) and Eat is ellagic acid, an antioxidative bis-catechol natural product, were studied by voltammetric and spectroelectrochemical techniques (UV-vis-NIR and electron paramagnetic resonance (EPR)). The electronic structures of the isolated forms (NBu4)(2)[(acac)(2)Ru(mu-E)Ru(acac)(2)] ( (NBu4)(2)[1]), (bpy)(2)Ru(mu-E)Ru(bpy)(2)]ClO4 ([2]ClO4), and [(pap)(2)Ru(mu-E)Ru(pap)(2)] ([3]) were characterized by density functional theory (DFT) in conjunction with EPR and UV vis NIR measurements. The crystal structure of (NBu4)(2)[1] revealed the meso form and a largely planar Ru(itE)Ru center. Several additional charge states of the compounds were electrochemically accessible and were identified mostly as complexes with noninnocently behaving pap(0/center dot-) or bridging ellagate (En-) anions (n = 2, 3, 4) but not as mixed-valence intermediates. The free anions En-, n = 1-4, were calculated by time-dependent DFT to reveal NIR transitions for the radical forms with n = 1 and 3 and a triplet ground state for the bis(o-semiquinone) dianion E2-.

The reactions of L-enantiopure alpha-amino acids (aaH) with Na2MoO4 led to the high-yield isolation of Mo(VI) complexes of general formula Mo2O4(OH)4(aaH). A similar outcome was achieved by using (NH4)6Mo7O24 in the place of Na2MoO4. Solid-state IR and NMR spectroscopy indicated the presence of cis-MoO2 units linked by a zwitterionic amino acid ligand, via a bidentate bridging coordination through the carboxylate group. Thus possible dinuclear and polynuclear structures are proposed on the basis of DFT calculations.

alpha-Phosphoglucomutase (alpha-PGM) plays an important role in carbohydrate metabolism by catalyzing the reversible conversion of alpha-glucose 1-phosphate to glucose 6-phosphate. Isolation of alpha-PGM activity from cell extracts of Lactococcus lactis strain MG1363 led to the conclusion that this activity is encoded by yfgH, herein renamed pgmH. Its gene product has no sequence homology to proteins in the alpha-D-phosphohexomutase superfamily and is instead related to the eukaryotic phosphomannomutases within the haloacid dehalogenase superfamily. In contrast to known bacterial alpha-PGMs, this 28-kDa enzyme is highly specific for alpha-glucose 1-phosphate and glucose 6-phosphate and showed no activity for mannose phosphate. To elucidate the function of pgmH, the metabolism of glucose and galactose was characterized in mutants overproducing or with a deficiency of alpha-PGM activity. Overproduction of alpha-PGM led to increased glycolytic flux and growth rate on galactose. Despite several attempts, we failed to obtain a deletion mutant of pgmH. The essentiality of this gene was proven by using a conditional knock- out strain in which a native copy of the gene was provided in trans under the control of the nisin promoter. Growth of this strain was severely impaired when alpha-PGM activity was below the control level. We show that the novel L. lactis alpha-PGM is the only enzyme that mediates the interconversion of alpha-glucose 1-phosphate to glucose 6-phosphate and is essential for growth.

Our study examines the functional and structural effects of amino acid substitution in the distal side of β-chains of human Hb Duarte (\documentclass[10pt]{article} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \pagestyle{empty} \oddsidemargin -1.0in \begin{document} \begin{equation*}{\alpha}_{2}{\beta}_{2}^{62{\mathrm{Ala}}{\rightarrow}{\mathrm{Pro}}}\end{equation*}\end{document}). We have compared the functional properties of the purified Hb Duarte with those of HbA, and through proton NMR and molecular dynamics simulations we have investigated their tertiary and quaternary structures. The variant exhibits an increased oxygen affinity with a normal Hill coefficient and Bohr effect. The abnormal function of Hb Duarte is attributed to the presence of a proline residue at the β62 position, since the functional properties of another Hb variant in the same position, Hb J-Europa (β62Ala→Asp), have been described as normal. Thereafter 1H-NMR studies have shown that the β62 Ala→Pro substitution causes structural modifications of the tertiary structure of the β globins, leaving the quaternary structure unaltered. These results have been confirmed by extensive all-atom molecular dynamics simulations. All these findings lead to the conclusion that the β62 Ala→Pro substitution produces a destabilization of the E-helix extending downward to the CD corner. Particularly, a cavity near the distal histidine of the β-chains, connecting the heme pocket to the solvent, is affected, altering the functional properties of the protein molecule.

Ce-doped borosilicate (BSG), phosphosilicate (PSG), and borophosphosilicate (BPSG) glasses (B:P:Si molar ratios 8:0:92, 0:8:92, and 8:8:84; Ce:Si molar ratio 1 x 10(-)(4) to 1 x 10(-)(2)) were prepared by the sol-gel method. High-resolution transmission electron microscopy (HRTEM), (31)P, (29)Si, and (11)B magic angle spinning nuclear magnetic resonance (MAS NMR), electron paramagnetic resonance (EPR), and UV-vis absorption investigations demonstrated that, in PSG and BPSG, Ce(3+) ions interact with phosphoryl, [O=PO(3/2)], metaphosphate, [O=PO(2/ 2)O](-), and pyrophosphate, [O=PO(1/2)O(2)](2)(-), groups, linked to a silica network. This inhibits both CeO(2) segregation and oxidation of isolated Ce(3+) ions to Ce(4+), up to Ce:Si = 5 x 10(-)(3). In BSG, neither trigonal [BO(3/2)] nor tetrahedral [BO(4/2)](-) boron units coordinate cerium; thus, Ce(3+) oxidation occurs even at Ce:Si = 1 x 10(-)(4), as in pure silica glass (SG). The homogeneous rare-earth dispersion in the host matrix and the stabilization of the Ce(3+) oxidation state enhanced the intensity of the photoluminescence emission in PSG and BPSG with respect to BSG and SG. The energy of the Ce(3+) emission band in PSG and BPSG matrixes agrees with the phosphate environment of the rare earth.

Conformational analysis of angiotensin I (AI) and II (AII) peptides has been performed through 2D (1) H-NMR spectroscopy in dimethylsulfoxide and 2,2,2-trifluoroethanol/H-2 O. The solution structural models of AI and AII have been determined in dimethylsulfoxide using NOE distance and (3) J (HNHalpha) coupling constants. Finally, the AI family of models resulting from restrained energy minimization (REM) refinement, exhibits pairwise rmsd values for the family ensemble 0.26 +/- 0.13 Angstrom, 1.05 +/- 0.23 Angstrom, for backbone and heavy atoms, respectively, and the distance penalty function is calculated at 0.075 +/- 0.006 Angstrom(2) . Comparable results have been afforded for AII ensemble (rmsd values 0.30 +/- 0.22 Angstrom, 1.38 +/- 0.48 Angstrom for backbone and heavy atoms, respectively; distance penalty function is 0.029 +/- 0.003 Angstrom(2) ). The two peptides demonstrate similar N-terminal and different C-terminal conformation as a consequence of the presence/absence of the His9-Leu10 dipeptide, which plays an important role in the different biological function of the two peptides. Other conformational variations focused on the side-chain orientation of aromatic residues, which constitute a biologically relevant hydrophobic core and whose inter-residue contacts are strong in dimethylsulfoxide and are retained even in mixed organic-aqueous media. Detailed analysis of the peptide structural features attempts to elucidate the conformational role of the C-terminal dipeptide to the different binding affinity of AI and AII towards the AT(1) receptor and sets the basis for understanding the factors that might govern free- or bound-depended AII structural differentiation. European Journal of Biochemistry

Summary • Changes in the physical state of cellular water and its interrelations with carbohydrate metabolism were studied during preplanting storage of tulip bulbs (Tulipa gesneriana‘Apeldoorn’). • Magnetic resonance imaging, light and scanning electron microscopy and high-performance anion exchange chromatography with pulsed amperometric detection were used to follow time-dependent changes during bulb storage at 17 or 20°C (nonchilled) or 4°C (chilled). • No visible differences in scale structure and central bud development were observed microscopically between chilled and nonchilled bulbs. However, the scales of the chilled bulbs exhibited higher water content, faster starch degradation and increased concentrations of sucrose and ethanol-soluble fructan. Quantitative measurements of magnetization transfer (MT) indicated a smaller fraction of a solid or a restricted-mobility proton pool in the scales of the chilled bulbs. By contrast, the MT effect was significantly higher in the central bud of the chilled than in the nonchilled bulbs. • Degradation of storage polysaccharides to low-molecular-weight sugar molecules during release from dormancy could be accompanied by local release of water molecules tightly bound to the polysaccharide granules into the bulk water, or by an influx of free water molecules due to increased osmotic potential caused by the raised sugar concentration, or by a combination of both effects.

Phosphorus (P) is the primary limiting nutrient for crop production in highly weathered tropical soils. The deficiency is mainly caused by strong adsorption of H2PO4− to Al- and Fe-(hydr)oxides, which turns large proportions of total P into a form that is unavailable to plants. Soil management modifies P dynamics. Some plants, including trees used in agroforestry systems, are known to accelerate P cycling. The objective of this paper was to use phosphorus 31 nuclear magnetic resonance (31PNMR) to evaluate the inorganic (Pi) and organic P (Po) compounds in Oxisol from two agroforestry (15 and 19 years old) and two conventional (full-sun, monoculture, ca. 15–20 and 20–24 years) coffee systems at three different depths (2–3, 10–15 and 40–60 cm). We hypothesised that the amounts of (1) organic P and (2) diester are higher in agroforestry fields than in conventional coffee fields and (3) the organic P and the diester decrease less with depth in the agroforestry systems than in the conventional systems. The soils were sampled from on-farm experiments in the Atlantic Coastal Rainforest, Brazil. The soil P was extracted with NaOH 0.5 M+EDTA 0.1 M. Resin chelex-X100 was used to remove the paramagnetic ions. The total P in the NaOH–EDTA extract was measured through ICP and the Pi by the ammonium molybdate–ascorbic acid method. Po was calculated as the difference between total P and Pi. The amount of Po was higher, the decrease of Po with depth was more sharp and the Po/total P was lower in the conventional systems than in the agroforestry systems. Based on literature and standards, 31PNMR signals were interpreted as inorganic orthophosphate, orthophosphate monoester (inositol phosphates and mononucleotides), orthophosphate diester (phospholipids, nucleic acids and teichoic acid) and pyrophosphates. The proportion of organic P (Po) was on average 47%, consisting of monoester (95%) and diester (5%). The amounts of diester phosphates did not differ between systems, but the proportion of diester to total spectra areas was higher and the decrease of diester with depth was less in the agroforestry than in the conventional systems. The proportions of inorganic P to total P consisted on average of 45% orthophosphate and 8% pyrophosphate. Our results suggest that agroforestry systems influence the dynamics of P through the conversion of part of the inorganic P into organic P. The effect was higher in deeper layers. Because the rate of cycling is higher for organic P than for inorganic P and for diester than for monoester, and because the P in deep layers is normally less available to crop plants, agroforestry would maintain larger fractions of P available to agricultural crops, thereby reducing P losses to the unavailable pools. The rate and the impacts of these changes on P cycling and efficiency of P use of the crops in the long-term need to be further examined and understood, for full evaluation of the importance of agroforestry in soil P utilisation.

Flavoproteins are ubiquitous redox proteins that are involved in many biological processes. In the majority of flavoproteins, the flavin cofactor is tightly but noncovalently bound. Reversible dissociation of flavoproteins into apoprotein and flavin prosthetic group yields valuable insights in flavoprotein folding, function and mechanism. Replacement of the natural cofactor with artificial flavins has proved to be especially useful for the determination of the solvent accessibility, polarity, reaction stereochemistry and dynamic behaviour of flavoprotein active sites. In this review we summarize the advances made in the field of flavoprotein deflavination and reconstitution. Several sophisticated chromatographic procedures to either deflavinate or reconstitute the flavoprotein on a large scale are discussed. In a subset of flavoproteins, the flavin cofactor is covalently attached to the polypeptide chain. Studies from riboflavinde deficient expression systems and site-directed mutagenesis suggest that the flavinylation reaction is a post-translational, rather than a cotranslational, process. These genetic approaches have also provided insight into the mechanism of covalent flavinylation and the rationale for this atypical protein modi. cation.

The structure of the phase-variable lipopolysaccharide (LPS) from the group B Neisseria meningitidis strain BZ157 galE was elucidated. The structural basis for the LPS's variation in reactivity with a monoclonal antibody (MAb) B5 that has specificity for the presence of phosphoethanolamine (PEtn) at the 3-position of the distal heptose residue (HepII) was established. The structure of the O-deacylated LPS was deduced by a combination of monosaccharide analyses, nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry. These analyses revealed the presence of a novel inner core oligosaccharide (OS) structure in the MAb B5 reactive (B5+) LPS that contained two PEtn residues simultaneously substituting the 3- and 6-positions of the HepII residue. The determination of this structure has identified a further degree of variability within the inner core OS of meningococcal LPS that could contribute to the interaction of meningococcal strains with their host.

OBJECTIVES: Bilirubin may protect against atherosclerotic cardiovascular disease by virtue of its anti-oxidative properties, but lower bilirubin may also be associated to atherogenic lipoprotein abnormalities. We determined associations of plasma (apo)lipoproteins and lipoprotein subfractions in subjects with and without type 2 diabetes mellitus (T2DM).DESIGN AND METHODS: Plasma (apo)lipoproteins, lipoprotein subfractions (nuclear magnetic resonance spectroscopy) and serum total bilirubin levels were determined in 53 T2DM patients and in 53 non-diabetic subjects.RESULTS: Triglycerides, large VLDL, small LDL and small HDL particles were increased (all pCONCLUSIONS: Increased triglycerides, as well as large VLDL and small LDL particles are associated negatively, whereas HDL cholesterol is associated positively with bilirubin in T2DM. The proposed pro-atherogenic effects of low bilirubin could in part be attributed to relationships with abnormalities in (apo)lipoproteins and lipoprotein subfraction characteristics.

Objectives: Low-normal thyroid function may relate to increases in plasma cholesterol and triglycerides, but effects on lipoprotein subfractions are largely unknown. Associations of alterations in lipoprotein metabolism and functionality with low-normal thyroid function could be more pronounced in Type 2 diabetes mellitus (T2DM). We determined relationships of plasma lipids and lipoprotein subfractions with thyroid-stimulating hormone (TSH) and free thyroxine (free T-4) in euthyroid subjects, and assessed whether such relationships are modified in the context of T2DM.Design and methods: TSH, free T4, (apo) lipoproteins and lipoprotein subfractions (nuclear magnetic resonance spectroscopy) were measured after an overnight fast in 61 T2DM subjects and 52 non-diabetic subjects.Results: TSH and free T-4 were similar in T2DM and non-diabetic subjects. Plasma triglycerides, large very low density (VLDL) particles, VLDL size and small low density lipoprotein (LDL) particles were increased, whereas high density lipoprotein (HDL) cholesterol was decreased in T2DM subjects (p = 0.05 for each). Age-, sex-, and diabetes status-adjusted multivariable linear regression analysis demonstrated that plasma triglycerides were associated positively with TSH (beta = 0.196, p = 0.039). Large VLDL particles (beta = - 0.215, p = 0.020) and VLDL size were inversely associated with free T4 (beta = - 0.285, p 0.10 for each). In all subjects combined, LDL and HDL subfraction characteristics were not significantly related to thyroid function status.Conclusions: Low-normal thyroid function may confer increased plasma triglycerides, large VLDL particles and increased VLDL particle size. These relationships are not to a major extent modified in the context of T2DM. (C) 2015 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Cement hydration occurs when water is added to cement powder, leading to the formation of crystalline products like Portlandite and the quasi-amorphous, poorly crystalline, calcium silicate hydrate (C-S-H) gel. Despite its importance in determining the final properties of the cement, many models exist for the nano and sub-nano level organization of this liquid stone. H-1 NMR relaxometry in White Portland Cement paste during hydration allowed us to monitor the formation and evolution of the multiscale porosity of the cement, with the formation of structures at nano and sub-nano levels of C-S-H gel (calcium silicate interlayer water, water in small and large gel pores) along with three low-mobility H-1 pools, identified as H-1 nuclei in C-S-H layers, likely belonging to OH groups, with H-1 nuclei in Portlandite, and in crystal water of Ettringite. By assuming these assignments, our data allowed us to compute the distances of pairs of H-1 nuclei in Portlandite and in crystal water ((1.9 +/- 0.2) angstrom and (1.6 +/- 0.1)angstrom, respectively), consistent with the known values of these distances. The picture of the porous structure at nano and sub-nano levels emerging from our results is consistent with the Jennings colloidal model for C-S-H gel. Moreover, the constant values observed during hydration of parameters extracted from our data analysis strongly support that model, being compatible with the picture of C-S-H gel developing in comparable-sized clumps of the same composition, but not easily interpretable by models proposing quasi continuous sheets of C-S-H layers.

The authors thank EaStCHEM, the Royal Society (for a Wolfson Merit Award for D.O’H.) and CNPq and FAPESP are also gratefully acknowledged for the studentships (to R.A.C. #2011/01170-1, FAPESP), as is CNPq for the fellowship (R.R.). Intramolecular CF···FC interactions in selected organofluorine compounds (all-syn-1,2,3,4- and all-syn-1,2,4,5-tetrafluorocyclohexane, 1,8-difluoronaphthalene, 4,5-difluorophenanthrene, 2,2′,5,5′-tetrafluorobiphenyl) were studied at the MP2/aug-cc-pVDZ level using the recently developed noncovalent interaction (NCI) method. For the optimized minima, all CF···FC interactions that are identified by this method are classified as attractive, even in those cases where suitable isodesmic reaction energies fail to provide evidence for an energetic stabilization. Possible relations between these interactions and the observable JFF spin–spin coupling constant values are discussed. Postprint

The influence of Lactobacillus rhamnosus GG and Bifidobacterium animalis subsp. lactis BB12 in co-fermentation with traditional starters on metabolite formation in set yoghurt was evaluated. Microbial activity during fermentation and refrigerated storage was investigated by monitoring bacterial population dynamics, milk acidification and overall changes in yoghurt metabolite profiles. A complementary metabolomics approach using solid-phase microextraction-gas chromatography/mass spectrometry and 1 H nuclear magnetic resonance resulted in the identification of 37 volatile and 43 non-volatile metabolites, respectively. Results demonstrated that the two probiotic strains did not influence acidity and the key-aroma volatile metabolites of set yoghurt. However, a contribution by the presence of L. rhamnosus GG on the non-volatile metabolite profile of yoghurt was specifically noticed during storage. Multivariate analysis allowed yoghurts fermented by different starter combinations and different durations of storage to be differentiated according to their metabolite profiles. This provides new insights regarding the impact of probiotics on the metabolome of yoghurt.

A systematic approach is described for building validated PLS models that predict cholesterol and triglyceride concentrations in lipoprotein subclasses in fasting serum from a normolipidemic, healthy population. The PLS models were built on diffusion-edited 1H NMR spectra and calibrated on HPLC-derived lipoprotein subclasses. The PLS models were validated using an independent test set. In addition to total VLDL, LDL, and HDL lipoproteins, statistically significant PLS models were obtained for 13 subclasses, including 5 VLDLs (particle size 64-31.3 nm), 4 LDLs (particle size 28.6-20.7 nm) and 4 HDLs (particle size 13.5-9.8 nm). The best models were obtained for triglycerides in VLDL (0.82 < Q2

The effect of low water contents and xylanases on wheat dough rheology is reported. Farinograph, dynamic oscillation, and creep-recovery measurements were performed using water concentrations from 34 to 44.8% (total basis). A water reduction from 43.5–44.8% to 34% increased resistance upon mixing as evidenced by higher Farinograph Brabender Unit values, increased G′ and G″-values, and decreased the maximum creep compliance by 1–2 orders of magnitude. Addition of an endoxylanase with a higher selectivity for water-unextractable arabinoxylans and an endoxylanase with a higher selectivity for water-extractable arabinoxylans both resulted in lower G′ and Farinograph dough consistencies and an increase in maximum creep compliance. The major influence of both xylanases was the release of water with possible water reductions of 2–5% (on water basis), though no distinct differences between the two xylanases were observed.

The varying coordination modes of the ambidentate ligand 2,2'-bipyridine-3,3'-diol (H2L) in a set of ruthenium complexes were demonstrated with special reference to the electronic features of the coligands, including sigma-donating acac(-) (= acetylacetonate) in Ru-III(acac)(2)(HL-) (1), strongly pi-accepting pap (= 2-phenylazopyridine) in Ru-II(pap)(2)(L2-) (2)/[(pap)(2)Ru-II(mu-L2-)Ru-II(pap)(2)](ClO4)(2) ([4](ClO4)(2)), and reported moderately pi-accepting bpy (= 2,2'-bypiridine) in [Ru-II(bpy)(2)(HL-)]PF6 ([5]PF6)/[(bpy)(2)Ru(mu-L2-)Ru(bpy)(2)](PF6)(2) ([7] (PF6)(2)). The single-crystal X-ray structures reveal that, in paramagnetic and electron paramagnetic resonance active 1 and reported diamagnetic [5]PF6, nearly planar monoanionic HL- coordinates to the metal ion via the N,N donors forming a five-membered chelate ring with hydrogen-bonded O-H center dot center dot center dot O function at the backbone of the ligand framework, as has also been reported in other metal complexes. However, structurally characterized diamagnetic 2 represents O-,O- bonded seven-membered chelate of fully deprotonated but twisted L2-. The nonplanarity of the coordinated L2- in 2 does not permit the second metal fragment {Ru(pap)(2)} or {Ru(bpy)(2)} or {Ru(acac)(2)} to bind with the available N,N donors at the back face of L2-. Further, the deprotonated form of the model ligand 2,2'-biphenol (H2L') yields Ru-II(pap)(2)(L'(2-)) (3); its crystal structure establishes the expected O-,O- bonded seven-membered chelate of nonplanar L'(2-) as in reported Ru-II(bpy)(2)(L'(2-)) (6), although {Ru(acac)(2)} metal precursor altogether fails to react with H2L'. All attempts to make diruthenium complex from {Ru(acac)(2)} and H2L failed; however, the corresponding {Ru(pap)(2)(2+)} derived dimeric [4](ClO4)(2) was structurally characterized. It establishes the symmetric N,O-/N,O- bridging mode of nonplanar L2- as in reported [7](PF6)(2). Besides structural and spectroscopic characterization of the newly developed complexes, the ligand (HL-, L2-, L'(2-), pap)-, metal-, or mixed metal-ligand-based accessible redox processes in 1(n) (n = +2, +1, 0, -1), 2(n)/3(n) (n = +2, +1, 0, -1, -2), and 4(n) (n = +4, +3, +2, +1, 0, -1) were analyzed in conjunction with density functional theory calculations.

Hybrid materials of the polydimethylsiloxane (PDMS)-Tetraethyl orthosilicate (TEOS) system have already been widely described by several authors, being their potential for biological applications largely studied. For some bone related applications, the addition of Ca to these systems is commonly accepted as necessary for the enhancement of bioactivity. However Ca is commonly introduced in the form of calcium nitrate, which requires a heat treatment step in order to eliminate the nitrate residues. The aim of the present work is to produce a PDMS-SiO2-CaO-TiO2 hybrid material through a sol-gel process, for potential biomedical applications. Calcium nitrate was used as the calcium source and to avoid the presence of nitrate residues in the final product, a heat-treating step at 400 degrees C was performed. Titanium was added to the hybrid system in order to enhance the thermal stability of the materials subjected to this temperature. TGA, FT-IR and Si-29 NMR techniques were used to understand the role of the calcium and titanium in the structure formation, and the way they influence the thermal stability of the PDMS -SiO2 system. A final material containing calcium, with no traces of nitrate and the maintenance of a significant amount of methyl groups was successfully obtained. (C) 2013 Elsevier B.V. All rights reserved.

An extremely stable water dispersion of cerium oxide nanoparticles was prepared by colloidal synthesis, using nitrilotriacetic acid (NTA) as a stabilizer. Based on FT-IR measurements, the surface characteristics of NTA-stabilized ceria nanoparticles are clarified and a fundamental stabilization mechanism is proposed. The mechanism is based on the combination of the ionic nature of cerium oxide surface and the inner-sphere complexation model. From an application perspective it is remarkable that ceria nanoparticle dispersions stabilized by NTA are stable at neutral pH, which makes them a potential successful additive in UV screening applications. QC 20140312