Relationship among Low T3 Levels, Type 3 Deiodinase, Oxidative Stress, and Mortality in Sepsis and Septic Shock: Defining Patient Outcomes.

Low T3 syndrome occurs frequently in patients with sepsis. Type 3 deiodinase (DIO3) is present in immune cells, but there is no description of its presence in patients with sepsis. Here, we aimed to determine the prognostic impact of thyroid hormones levels (TH), measured on ICU admission, on mortality and evolution to chronic critical illness (CCI) and the presence of DIO3 in white cells.

Micro-Scale Shear Kneading-Gluten Network Development under Multiple Stress-Relaxation Steps and Evaluation via Multiwave Rheology.

To evaluate the kneading process of wheat flour dough, the state of the art is a subsequent and static measuring step on kneaded dough samples. In this study, an in-line measurement setup was set up in a rheometer based on previously validated shear kneading processes. With this approach, the challenge of sample transfer between the kneader and a measurement device was overcome.

Size-Dependent Variability in Flow and Viscoelastic Behavior of Levan Produced by TMW 2.1191.

Levan is a fructan-type exopolysaccharide which is produced by many microbes from sucrose via extracellular levansucrases. The hydrocolloid properties of levan depend on its molecular weight, while it is unknown why and to what extent levan is functionally diverse depending on its size. The aim of our study was to gain deeper insight into the size-dependent functional variability of levan.

VUV-photolysis of aqueous solutions of hydroxylamine and nitric oxide. Effect of organic matter: phenol.

VUV-irradiation of aqueous solutions containing hydroxylamine (NHOH) in its acid form (NHOH) and phenol (CHOH) results in the simultaneous mineralization of the organic substrate and the almost quantitative reduction of NHOH to ammonium ions (NH). Irradiation of aqueous solutions of NHOH in the absence of organic substrates showed the formation of nitrate (NO) and nitrite (NO) and minor quantities of NH. In line with these experiments, VUV-irradiation of aqueous solutions of nitrogen monoxide (NO˙) yields NH only when CHOH is simultaneously mineralized.

Rheological characterization of the exopolysaccharide Paenan in surfactant systems.

Rheology-controlling agents are of importance for numerous products in a variety of industries. Replacement of synthetic chemicals with natural additives is desired in light of current environmental awareness and limited fossil resources. This study investigates the rheological features of Paenan, an exopolysaccharide produced by Paenibacillus polymyxa.

Deformation and rupture of Dunaliella salina at high shear rates without the use of thickeners.

Background: High-density cultures require operating below the critical threshold of shear stress, in order to avoid reducing the specific growth rate of the cells. When determining this threshold, direct inspection of the cells in flow provides insight into the conditions of shearing.

Objective: Aim of this study was using a novel rheo-optical setup for the observation of cells in laminar shear flow and the determination of the critical shear stress required to damage them in their natural environment.

Continuous process of the vacuum ultraviolet- (VUV-) photochemical oxidation of thiophene in the gas phase.

Thiophene was taken as a model compound for investigations on the efficiency of a continuous process of the vacuum-ultraviolet- (VUV-) photochemically initiated oxidation and mineralization of sulfur containing organic compounds in the gas phase. In the presence of molecular oxygen, atomic oxygen and ozone were photochemically generated and are assumed to initiate or participate in the (thermal) oxidation network. Addition of water vapor for an additional initiation of the oxidation by hydroxyl radicals did not accelerate the process.

The use of chemical actinometry for the evaluation of the light absorption efficiency in scattering photopolymerizable miniemulsions.

Oil-in-water miniemulsions containing a mixture of monomers as the dispersed organic phase have been shown recently to be promising media for the development of photoinitiated polymerization processes. Albeit a crucial factor for a successful application, the efficiency of light absorption by the photoinitiator in these highly scattering systems is difficult to evaluate. In this work, a well-characterized water insoluble chemical actinometer (DFIS) replaced the oil-soluble photoinitiator, and was used as a probe and a model for UV light absorption in miniemulsions of variable droplet sizes and organic phase compositions (i.

Preparative mass-spectrometry profiling of bioactive metabolites in Saudi-Arabian propolis fractionated by high-speed countercurrent chromatography and off-line atmospheric pressure chemical ionization mass-spectrometry injection.

Propolis is a glue material collected by honeybees which is used to seal cracks in beehives and to protect the bee population from infections. Propolis resins have a long history in medicinal use as a natural remedy. The multiple biological properties are related to variations in their chemical compositions.

Micellar control of the photooxidation pathways of 10-methyl phenothiazine: electron versus energy transfer mechanisms.

10-Methyl phenothiazine (MPS) was chosen as a model compound to investigate the effects of compartmentalisation and of charged interfaces on the primary mechanisms involved in the phototoxic reactions related to phenothiazine drugs. Two most important pathways resulting from the interaction of the triplet excited state of MPS ((3)MPS*) with molecular oxygen ((3)O2) have to be considered: (i) energy transfer producing singlet oxygen ((1)O2) and (ii) electron transfer generating the superoxide anion (O2˙(-)) and the radical cation (MPS˙(+)). The quantum yields of (1)O2 production by MPS solubilized in the dispersed pseudo-phase of aqueous micellar systems were found to be similar to those determined in solvents of various polarities, regardless of the anionic or cationic nature of the surfactant (SDS or CTAC).

Self sensitized photooxidation of N-methyl phenothiazine: acidity control of the competition between electron and energy transfer mechanisms.

The reaction pathways following electronic excitation of 10-methyl phenothiazine (MPS) in the presence of oxygen have been investigated as a contribution to establish the mechanisms involved in the phototoxic reactions related to phenothiazine drugs. In the context of previously published results, the pathways of oxidation via the radical cation and/or by reactive oxygen species, such as singlet oxygen and superoxide anion, are of particular interest. The effects of polarity of the medium as well as of proton donors on the different reaction pathways, in particular on the formation of reactive oxygen species and the intermediates of the oxidation of 10-methyl phenothiazine, have been investigated.

Formation of hydrogen peroxide by VUV-photolysis of water and aqueous solutions with methanol.

The hydrogen peroxide production upon vacuum ultraviolet (VUV) irradiation of water is reviewed, because published results from the last 10 years lead to conflicting mechanistic interpretations. This work confirms that in pure water, hydrogen peroxide is only produced in the presence of molecular oxygen. Mechanistic schemes explain these findings and confirm earlier statements that recombination of hydroxyl radicals is kinetically disfavoured.

Oxidation of polystyrene aerosols by VUV-photolysis and/or ozone.

Aerosols of submicron polystyrene particles were oxidized by either vacuum-ultraviolet (VUV) irradiation in the presence of molecular oxygen (O(2)) and/or by ozone (O(3)). Different degrees of oxidation and oxidative degradation were reached by VUV-photolysis depending on radiant energy, O(2) and H(2)O concentrations in the bulk gas mixture as well as on particle diameter. The same functionalization was obtained by exposing the aerosol to O(3), however, oxidation, in particular oxidative degradation, was less efficient.

Quenching of the fluorescence of aromatic pterins by deoxynucleotides.

Steady-state and time-resolved studies of the fluorescence of four aromatic unconjugated pterins (pterin (Ptr), 6-(hydroxymethyl)pterin (Hmp), 6-methylpterin (Mep), and 6,7-dimethylpterin (Dmp)) in aqueous solutions in the presence of different nucleotides (2'-deoxyguanosine 5'-monophosphate (dGMP), 2'-deoxyadenosine 5'-monophosphate (dAMP), and 2'-deoxycytosine 5'-monophosphate (dCMP)) have been performed using the single-photon counting technique. The singlet excited states of acid forms of pterins are deactivated by purine nucleotides (dGMP and dAMP) via a combination of dynamic and static processes. The efficiency of the dynamic quenching is high, independently of the nature of the purine base of the nucleotide and of the chemical structure of the substituents linked to the pterin moiety.

Histone deacetylase inhibitors sensitize tumour cells for cytotoxic effects of natural killer cells.

Histone deacetylase inhibitors (HDIs) are emerging as potent anti-tumour agents which induce cell cycle arrest, differentiation and/or apoptosis in many tumour cells. Furthermore, they render tumour cells more sensitive to other therapeutic regimens like ionizing radiation, chemotherapy and recombinant tumour necrosis factor-related apoptosis-inducing ligand (TRAIL). Here, we show that the HDIs suberoylanilide hydroxamic acid (SAHA; vorinostat), sodium butyrate (NaB) and MS-275 sensitized DAOY and PC3 tumour cells for the cytotoxic effects of IL-2-activated PBMCs.

Photosensitization of 2'-deoxyadenosine-5'-monophosphate by pterin.

UV-A radiation (320-400 nm) induces damages to the DNA molecule and its components through photosensitized reactions. Pterins, heterocyclic compounds widespread in biological systems, participate in relevant biological processes and are able to act as photosensitizers. We have investigated the photosensitization of 2'-deoxyadenosine-5'-monophosphate (dAMP) by pterin (PT) in aqueous solution under UV-A radiation.

Mineralization of CCl4 by the UVC-photolysis of hydrogen peroxide in the presence of methanol.

A method for a photochemically induced mineralization of CCl4 is described in which use is made of reductive radicals. The UVC-photolysis (254 nm) of H2O2 added to aqueous solutions of CCl4 is leading to the homolysis of the oxidant yielding hydroxyl radicals (HO) that subsequently react with added methanol to generate hydroxymethyl radicals (CH2OH). The latter radicals initiate mineralization of CCl4 by reductive C-Cl bond splitting.

Characterization of nanostructured surfaces generated by reconstitution of the porin MspA from Mycobacterium smegmatis.

Nanostructures with long-term stability at the surface of gold electrodes are generated by reconstituting the porin MspA from Mycobacterium smegmatis into a specially designed monolayer of long-chain lipid surfactant on gold. Tailored surface coverage of gold electrodes with long-chain surfactants is achieved by electrochemically assisted deposition of organic thiosulfates (Bunte salts). The subsequent reconstitution of the octameric-pore MspA is guided by its extraordinary self-assembling properties.

Singlet oxygen (O2(1Deltag)) quenching by dihydropterins.

Pterins belong to a class of heterocyclic compounds present in a wide range of living systems. They participate in relevant biological functions and are involved in different photobiological processes. Dihydropterins are one of the biologically active forms of pterins.

Photooxidation of pterin in aqueous solutions: biological and biomedical implications.

Studies of the photochemical reactivity of pterin (= 2-aminopteridin-4(3H)-one; PT) in acidic (pH 5.0-6.0) and alkaline (pH 10.

Reactivity of conjugated and unconjugated pterins with singlet oxygen (O2(1Deltag)): physical quenching and chemical reaction.

Pterins (PTs) belong to a class of heterocyclic compounds present in a wide range of living systems. They participate in relevant biological functions and are involved in different photobiological processes. We have investigated the reactivity of conjugated PTs (folic acid [FA], 10-methylfolic acid [MFA], pteroic acid [PA]) and unconjugated PTs (PT, 6-hydroxymethylpterin [HPT], 6-methylpterin [MPT], 6,7-dimethylpterin [DPT], rhamnopterin [RPT]) with singlet oxygen (1O2) in aqueous solutions, and compared the efficiencies of chemical reaction and physical quenching.

Vacuum-ultraviolet photochemically initiated modification of polystyrene surfaces: morphological changes and mechanistic investigations.

Vacuum-ultraviolet (VUV) irradiation (lambda(exc): 172 +/- 12 nm) of polystyrene films in the presence of oxygen produced not only oxidatively functionalized surfaces, but generated also morphological changes. Whereas OH- and C=O-functionalized surfaces might be used for e.g.

Myoglobin modified electrodes as anchors for d metal cationic complexes.

The capability of adsorption of different electroactive cationic Re(V)-amine complexes onto myoglobin-containing electrodes has been investigated. The goal of this work was the development of an Au/thiol/myo electrode and, after incubation of such ensemble in the presence of three different Re(V)-amine complexes, the evaluation of the extent of surface coverage by the complexes (as a way to evaluate the interaction complex-protein) using electrochemical techniques. Our results showed that a protein-containing electrode could therefore be used for the detection of the interaction of small electroactive cationic complexes and the biomolecule.

Substituent effects on the photophysical properties of pterin derivatives in acidic and alkaline aqueous solutions.

Pterins are heterocyclic compounds with important biological functions, and most of them may exist in two acid-base forms in the pH range between 3 and 13 in aqueous solution. In this work, the photophysical properties of acid and basic forms of six compounds of the pterin family (6-hydroxymethylpterin [HPT], 6-methylpterin [MPT], 6,7-dimethylpterin [DPT], rhamnopterin [RPT], N-methylfolic acid [MFA], and pteroic acid [PA]) have been studied. The effects of the chemical nature of the substituents at position 6 of the pterin moiety and the effects of the pH on the absorption and emission properties are analyzed.

157 nm pellicles (thin films) for photolithography: mechanistic investigation of the VUV and UV-C photolysis of fluorocarbons.

The use of 157 nm as the next lower wavelength for photolithography for the production of semiconductors has created a need for transparent and radiation-durable polymers for use in soft pellicles, the polymer films which protect the chip from particle deposition. The most promising materials for pellicles are fluorinated polymers, but currently available fluorinated polymers undergo photodegradation and/or photodarkening upon long term exposure to 157 nm irradiation. To understand the mechanism of the photodegradation and photodarkening of fluorinated polymers, mechanistic studies on the photolysis of liquid model fluorocarbons, including perfluorobutylethyl ether and perfluoro-2H-3-oxa-heptane, were performed employing UV, NMR, FTIR, GC, and GC/MS analyses.