Determination of Tertiary-butylhydroquinone and Its Metabolites in Rat Serum by Liquid Chromatography–Ion Trap Mass Spectrometry

A new method applying sensitive and selective liquid chromatography coupled with mass spectrometry (LC/MS/MS) for analyzing tertiary-butylhydroquinone (TBHQ) and its metabolites in rat serum was validated. Using an extracted ion chromatogram (EIC) of m/z 149, free TBHQ was observed in rat serum after dosing TBHQ at 350 mg/kg to male and female Sprague–Dawley (SD) rats. Four major metabolites of TBHQ were identified—a TBHQ-sulfate, two TBHQ-sulfate-derived substances and a TBHQ-glucuronide through MSⁿ spectra. Besides its simplicity, the sample treatment allows one to obtain a very good recovery of analysts, namely around 95%. This result suggests that the method described here is useful for the analysis of TBHQ and its metabolites in rat serum. Moreover, the metabolism of TBHQ was investigated using the method. After oral administration, TBHQ appear to be more completely absorbed and bio-transformed by males than females, which may result in higher acute oral toxicity of TBHQ for males than females.     

Diagnostic Performance of 1→3-β-d-Glucan in Neonatal and Pediatric Patients with Candidemia

Fungal sepsis is one of the major problems in neonatal and pediatric care unit settings. The availability of new diagnostic techniques could allow medical practitioners to rapidly identify septic patients and to improve their outcome. The aim of this study was to evaluate the performance of the 1→3-β-d-glucan (BDG), individually and in comparison with the Candida mannan (CM) antigen, in ten preterm infants and five onco-haematological pediatric patients with Candida bloodstream infections already proven by positive culture. The serum levels of BDG were >80 pg/mL on the same day as a positive blood culture in all examined patients, while CM antigen was negative in the patients with C. parapsilosis fungemia and in one further case due to C. albicans. These results suggest that a regular monitoring of serum circulating antigens (i.e., 1→3-β-d-glucan) combined with other microbiological and clinical information, may allow earlier and accurate diagnosis. However, further studies are necessary to confirm its usefulness in routine clinical practice.     

The Human Host Defense Ribonucleases 1, 3 and 7 Are Elevated in Patients with Sepsis after Major Surgery—A Pilot Study

Sepsis is the most common cause of death in intensive care units and associated with widespread activation of host innate immunity responses. Ribonucleases (RNases) are important components of the innate immune system, however the role of RNases in sepsis has not been investigated. We evaluated serum levels of RNase 1, 3 and 7 in 20 surgical sepsis patients (Sepsis), nine surgical patients (Surgery) and 10 healthy controls (Healthy). RNase 1 and 3 were elevated in Sepsis compared to Surgery (2.2- and 3.1-fold, respectively; both p < 0.0001) or compared to Healthy (3.0- and 15.5-fold, respectively; both p < 0.0001). RNase 1 showed a high predictive value for the development of more than two organ failures (AUC 0.82, p = 0.01). Patients with renal dysfunction revealed higher RNase 1 levels than without renal dysfunction (p = 0.03). RNase 1 and 3 were higher in respiratory failure than without respiratory failure (p < 0.0001 and p = 0.02, respectively). RNase 7 was not detected in Healthy patients and only in two patients of Surgery, however RNase 7 was detected in 10 of 20 Sepsis patients. RNase 7 was higher in renal or metabolic failure than without failure (p = 0.04 and p = 0.02, respectively). In conclusion, RNase 1, 3 and 7 are secreted into serum under conditions with tissue injury, such as major surgery or sepsis. Thus, RNases might serve as laboratory parameters to diagnose and monitor organ failure in sepsis.     

Tissue Distribution of α- and γ-Tocotrienol and γ-Tocopherol in Rats and Interference with Their Accumulation by α-Tocopherol

The aim of this study was to evaluate tissue distribution of vitamin E isoforms such as α- and γ-tocotrienol and γ-tocopherol and interference with their tissue accumulation by α-tocopherol. Rats were fed a diet containing a tocotrienol mixture or γ-tocopherol with or without α-tocopherol, or were administered by gavage an emulsion containing tocotrienol mixture or γ-tocopherol with or without α-tocopherol. There were high levels of α-tocotrienol in the adipose tissue and adrenal gland, γ-tocotrienol in the adipose tissue, and γ-tocopherol in the adrenal gland of rats fed tocotrienol mixture or γ-tocopherol for 7 weeks. Dietary α-tocopherol decreased the α-tocotrienol and γ-tocopherol but not γ-tocotrienol concentrations in tissues. In the oral administration study, both tocopherol and tocotrienol quickly accumulated in the adrenal gland; however, their accumulation in adipose tissue was slow. In contrast to the dietary intake, α-tocopherol, which has the highest affinity for α-tocopherol transfer protein (αTTP), inhibited uptake of γ-tocotrienol to tissues including adipose tissue after oral administration, suggesting that the affinities of tocopherol and tocotrienol for αTTP in the liver were the critical determinants of their uptake to peripheral tissues. Vitamin E deficiency for 4 weeks depleted tocopherol and tocotrienol stores in the liver but not in adipose tissue. These results indicate that dietary vitamin E slowly accumulates in adipose tissue but the levels are kept without degradation. The property of adipose tissue as vitamin E store causes adipose tissue-specific accumulation of dietary tocotrienol.     

Enhancement of γ-aminobutyric acid in germinated paddy by soaking in combination with anaerobic and fluidized bed heat treatment

Enhancement of γ-aminobutyric acid (GABA) in germinated grain could be induced via environmental stresses. Soaking in combination with anaerobic treatment (SA) as well as soaking in combination with anaerobic and heat treatment (SAH) are proposed in this work to increase the GABA content in germinated paddy; the results were compared with that obtained via a conventional germination (soaking) method (CS). The quality of germinated rice prepared from paddy (GP) by CS, SA and SAH after shade drying and fluidized bed drying in terms of the GABA content, number of fissured kernels and textural property was also investigated. The results showed that the GP prepared via SAH had the highest GABA content. The GABA contents in GP prepared by CS, SA and SAH increased 15, 25 and 29 times as compared to that of the un-germinated brown rice, respectively. However, SAH resulted in the higher number of fissured kernels as compared with CS and SA. After fluidized bed drying at 150 °C, the GABA content in GP did not decrease, but the number of fissured kernels of the fluidized bed dried samples was higher than that of the shade-dried samples. However, the head brown rice yield of the fluidized bed dried samples was higher than that of the shade-dried samples. Hardness and stickiness of the fluidized bed dried samples prepared by the three germination methods were not significantly different; exception held nevertheless for the hardness value of the complete kernels obtained via CS.     

Formation of Ti2AlN by Solid–Gas Combustion Synthesis with AlN- and TiN-Diluted Samples in Nitrogen

Ti₂AlN was prepared by a self-propagating high-temperature synthesis (SHS) in nitrogen at 0.45 and 0.79 MPa. TiN and AlN were adopted as diluents in the Ti–Al powder compacts and their contents varied from 8.3 to 25 mol%. Formation of Ti₂AlN along with intermediates like TiN, Ti₃Al, and TiAl was identified. For the AlN-added samples, the degree of dilution at 11.7 mol% brought about the optimum formation up to 81.8% Ti₂AlN in nitrogen of 0.79 MPa. When the sample was diluted with 20 mol% TiN, the SHS process yielded the highest percentage of Ti₂AlN reaching 84.3% in nitrogen of 0.45 MPa.     

Photocatalytic Degradation of Phenol and Methyl Orange with Titania-Based Photocatalysts Synthesized by Various Methods in Comparison with ZnO–Graphene Oxide Composite

Topics in Catalysis - Photocatalysis is one of the effective methods to treat wastewater and degrade pollutants. Titania (TiO2) is usually chosen based on its superior properties and its high...     

Use of Furandicarboxylic Acid and Its Decyl Ester as Additives in the Fischer’s Glycosylation of Decanol by d-Glucose: Physicochemical Properties of the Surfactant Compositions Obtained

2,5-Furandicarboxylic acid is a promising bio-based platform chemical that may serve as a ‘green’ substitute for terephthalate in polyesters. In the present work, straightforward glycosylation of decanol with unprotected and non-activated d-glucose was performed under reduced quantities of sulfuric acid as catalyst (down to 0.9 mol%) in the presence of 2,5-furandicarboxylic acid or its n-decyl ester as additive. Yield of decyl monoglucosides was highly improved by the use of the additives. Moreover, the presence of additive also limited the colouration of the reaction. The physical and chemical properties of the surfactant composition produced were studied and compared to reference compositions. The ultimate biodegradability of furan-2,5-dicarboxylic acid (FDCA) and its n-decyl ester formed or produced in the bulk reaction medium was also studied in order to assess its potential use in surfactant industry.     

Evaluation of Alternative Risk Stratification Systems in a Large Series of Solitary Fibrous Tumors with Molecular Findings and Ki-67 Index Data: Do They Improve Risk Assessment?

The clinical evolution of solitary fibrous tumors (SFTs) is often uncertain and several risk stratification systems (RSS) have been proposed. The Demicco et al. RSS is the most frequently implemented. In this study we aim to validate two alternative RSS (Sugita et al. and G-Score) using results for the Demicco RSS from a previous study of 97 SFTs. In addition, we aim to determine whether reclassified cases had any distinctive molecular features. As the Sugita et al. system substitutes mitotic count with Ki-67 index we also investigated whether Ki-67 results for tissue microarrays are comparable to those obtained using whole tissue sections. In the present study we detected that many cases classified by Demicco RSS as low-risk were reclassified as intermediate risk using the new system (G-score RSS). Kaplan-Meier survival plots for G-Score RSS showed that the low-risk and intermediate-risk SFTs had a similar evolution that contrasted with the more aggressive high-risk group. Moreover, the similar evolution in both low and intermediate-risk groups occurred despite the G-score system being stricter in classifying low-risk tumors. We observed that Sugita RSS does not provide any better risk stratification in comparison with the Demicco RSS, and testing both RSS in our series produced similar Kaplan-Meier survival data. We found some discordant results when comparing whole sections and the corresponding tissue microarrays samples, finding the hotspot areas easier to locate in whole sections. Forty-one SFTs with initial low-risk assigned by the Demicco RSS were reclassified as intermediate-risk by G-score finding both TP53 and HTER mutations in four cases, only HTER mutation in 11 cases, and only TP53 mutation in 2 cases. All six cases of SFT classified as high-risk by both the Demicco and G-score RSS suffered recurrence/metastasis, and half showed both TP53 and HTER mutations. Five SFTs were categorized as low-risk by both Demicco and G-score, of which 4 cases revealed HTER mutation. Regarding the outcome of these 5 patients, two were lost to follow-up, and one of the remaining three patients suffered recurrence. We believe that although the presence of both TP53 and HTER mutations may confer or be related to poor evolution, the isolated presence of HTER mutation alone would not necessarily be related to poor outcome. The G-score RSS more accurately identified low-risk patients than the other two risk models evaluated in the present series. Late recurrence/metastasis may occasionally be observed even in low-risk SFTs categorized by stricter classification systems such as the G-score RSS. These findings support the possibility that additional, as yet unknown factors may influence the clinical evolution of SFTs. In conclusion, given the possibility of late recurrence, long-term follow-up is recommended for all SFT patients, even in cases classified as low risk by the stricter G-score system. An integration of clinical, radiological, pathological, and molecular findings may improve SFT risk stratification and better predict patient outcome.     

Kinetic and Thermodynamic Separation of Cu(II) and Fe(III) by Liquid-Liquid Extraction with a β-Hydroxy-oxime in Toluene

Abstract

A quantitative study of the thermodynamic and kinetic separation of Cu(II) and Fe(III) by liquid-liquid extraction with toluene solutions of the oxime 2-hydroxy-5-t-octyl (acetophenone oxime) has been conducted. On the basis of the stoichiometry, equilibrium constants, rate laws and rate constants of the extraction reactions of Cu(II) and Fe(III) an equation has been derived which describes how the separation of Cu from Fe varies with the chemical composition of the system, the hydrodynamics of the extracting apparatus and the contact time between the aqueous and the organic phases. Our results show that separations which are not feasible thermodynamically are possible when the contact time between the two phases is kept much shorter than that required to reach equilibrium.     

Formation of 8-oxo-2′-deoxyguanosine in the DNA of human diploid fibroblasts by treatment with linoleic acid hydroperoxide and ferric ion

Lipid peroxides are suggested to be related to the occurrence of a variety of diseases including cancer and atherosclerosis. We examined whether lipid peroxides cause oxidative damage to DNA in intact cells. Linoleic acid hydroperoxide (LOOH) and ferric chloride were used at concentrations at which separate treatment had no effect on the formation of 8-oxo-2′-deoxyguanosine (8-oxodG) in DNA or the survival rate of cultured human diploid fibroblasts, TIG-7. The amount of 8-oxodG in the cellular DNA increased significantly when TIG-7 cells were treated concurrently with LOOH and ferric chloride. In a LOOH concentration-dependent manner 8-oxodG was formed. However, no significant induction of the activities of superoxide dismutases, catalase, or glutathione peroxidase was observed under these conditions. The formation of 8-oxodG by lipid hydroperoxides seems to be due to the generation of reactive species other than superoxide radicals and hydrogen peroxide. These results indicate that some species formed during the reaction of lipid hydroperoxides with ferric ion can cause oxidative damage to DNA.     

Preparation of Mn–FeOx/CNTs catalysts by redox co-precipitation and application in low-temperature NO reduction with NH3

A novel redox co-precipitation method was firstly adopted to prepare the Mn–FeO_x/CNTs catalysts for use in low-temperature NO reduction with NH₃. The catalysts were possessed of amorphous structure and exhibited 80–100% NO conversion at 140–180 °C at a high space velocity of 32,000 h^− 1.     

On-line detection of bed fluidity in gas–solid fluidized beds with liquid injection by passive acoustic and vibrometric methods

Passive acoustic and vibrometric methods were investigated for the detection and monitoring of changes in bed fluidity in a large scale gas–solid fluidized bed after liquid injection. Water was injected into a 9 tonne air-fluidized bed of silica sand using an industrial nozzle and pre-mixer assembly. Acoustic signals were recorded using non-intrusive and externally mounted microphones. Vibration data was recorded using an accelerometer mounted to a rod inserted into the bed. The signals were analyzed offline using Fourier and wavelet analysis techniques. The average frequency of the acoustic and vibration measurements decreased as the bed solids dried while the standard deviation of the coefficients in the 10–20 kHz band characterized from wavelet analysis increased during drying. Samples from the bed were taken and evaluated for flowability by measuring the median avalanche time with a Revolution Powder analyzer. Linear and power law regressions of the wavelet and Fourier analyzed vibration measurements provided a reliable correlation of the flowability of the bed solids and thus could be successfully used as a passive and real-time monitoring method of bed fluidity.     

Selective Oxidation of 1- and 2-Propanol with Molecular Oxygen by Noble Metal Catalysis in “Supercritical” Carbon Dioxide

The selective oxidation of 1- and 2-propanol by molecular oxygen over supported platinum catalysts was investigated in supercritical carbon dioxide as an environmentally benign and safe reaction medium. The reaction occurs exclusively to acetone or propionic aldehyde and propionic acid in a single-phase region at 100–190 bar and at a mild temperature (40 °C). Compared to conversions in aqueous solution, catalyst stability is significantly enhanced in supercritical carbon dioxide and depends on the oxygen concentration in the reaction medium. Thus, at least a fourfold higher substrate/catalyst ratio than with water as a solvent can be used. Platinum catalysts with nanoporous silica (MCM-41, silicalite-1) as a support are also active for the oxidation of 2-propanol in supercritical carbon dioxide.     

A Simple and Highly Selective Biomimetic Oxidation of Alcohols with Hypervalent Iodine(III) Reagent Catalyzed by β-Cyclodextrin in Water

Abstract  

A simple, mild and highly efficient biomimetic oxidation of alcohols to the corresponding aldehydes or ketones with hypervalent iodine(III) reagent catalyzed by β-cyclodextrin was reported. β-cyclodextrin serves as a biological catalyst to enhance the reaction remarkably. The oxidation proceeded in water to afford aldehydes or ketones in excellent yields and high selectivity without remarkable over-oxidation to carboxylic acids. Selective oxidation of primary alcohols in the presence of secondary alcohols was also achieved. A possible mechanism for the oxidation was proposed.     

Frequency and Voltage Dependence of Interface States and Series Resistance in Ti/Au/p-Si Diodes with 100 μm and 200 μm Diameter Fabricated by Photolithography

Silicon - Ti/Au/p-Si diodes with the diameters of 100 and 200 μ m were fabricated by photolithographic technique. Capacitance–voltage (C–V) and conductance–voltage...     

Influence of Residual Water in a Glass on Its Rheological and Relaxation Properties (by the Example of a 5Na2O · 95B2O3Glass)

Glasses of the 5Na₂O · 95B₂O₃(mol %) composition synthesized at a temperature of 1100°C for 180 and 20 min are studied. The temperature dependences of the viscosity and the thermal expansion of glasses are obtained. The thermal expansion coefficients and glass transition temperatures of the studied glasses are determined, and the parameters of structural relaxation (the constant characterizing the width of the spectrum of relaxation times, the relaxation modulus equal to the ratio of the viscosity to the relaxation time, and the relaxation time at zero reciprocal temperature) are calculated from the dilatometric curves measured at temperatures close to the glass transition range. The water content in the studied glasses is estimated by comparing the obtained dependence of the viscosity on the water content with the data available in the literature for glasses of a similar composition. The assumption is made that the structural relaxation time in sodium borate glass decreases with an increase in the water content.