bluuebunny/crossref_metadata_2025 huggingface dataset:
SH2B1 Enhances Insulin Sensitivity by Both Stimulating the Insulin Receptor and Inhibiting Tyrosine Dephosphorylation of Insulin Receptor Substrate Proteins
Authors: Morris David L. , Cho Kae Won , Zhou Yingjiang , Rui Liangyou
Published: June 2009

OBJECTIVE

SH2B1 is a SH2 domain-containing adaptor protein expressed in both the central nervous system and peripheral tissues. Neuronal SH2B1 controls body weight; however, the functions of peripheral SH2B1 remain unknown. Here, we studied peripheral SH2B1 regulation of insulin sensitivity and glucose metabolism.

RESEARCH DESIGN AND METHODS

We generated TgKO mice expressing SH2B1 in the brain but not peripheral tissues. Various metabolic parameters and insulin signaling were examined in TgKO mice fed a high-fat diet (HFD). The effect of SH2B1 on the insulin receptor catalytic activity and insulin receptor substrate (IRS)-1/IRS-2 dephosphorylation was examined using in vitro kinase assays and in vitro dephosphorylation assays, respectively. SH2B1 was coexpressed with PTP1B, and insulin receptor–mediated phosphorylation of IRS-1 was examined.

RESULTS

Deletion of peripheral SH2B1 markedly exacerbated HFD-induced hyperglycemia, hyperinsulinemia, and glucose intolerance in TgKO mice. Insulin signaling was dramatically impaired in muscle, liver, and adipose tissue in TgKO mice. Deletion of SH2B1 impaired insulin signaling in primary hepatocytes, whereas SH2B1 overexpression stimulated insulin receptor autophosphorylation and tyrosine phosphorylation of IRSs. Purified SH2B1 stimulated insulin receptor catalytic activity in vitro. The SH2 domain of SH2B1 was both required and sufficient to promote insulin receptor activation. Insulin stimulated the binding of SH2B1 to IRS-1 or IRS-2. This physical interaction inhibited tyrosine dephosphorylation of IRS-1 or IRS-2 and increased the ability of IRS proteins to activate the phosphatidylinositol 3-kinase pathway.

CONCLUSIONS

SH2B1 is an endogenous insulin sensitizer. It directly binds to insulin receptors, IRS-1 and IRS-2, and enhances insulin sensitivity by promoting insulin receptor catalytic activity and by inhibiting tyrosine dephosphorylation of IRS proteins.
Tissue-Specific Remodeling of the Mitochondrial Proteome in Type 1 Diabetic Akita Mice
Authors: Bugger Heiko , Chen Dong , Riehle Christian , Soto Jamie , Theobald Heather A. , Hu Xiao X. , Ganesan Balasubramanian , Weimer Bart C. , Abel E. Dale
Published: June 2009

OBJECTIVE

To elucidate the molecular basis for mitochondrial dysfunction, which has been implicated in the pathogenesis of diabetes complications.

RESEARCH DESIGN AND METHODS

Mitochondrial matrix and membrane fractions were generated from liver, brain, heart, and kidney of wild-type and type 1 diabetic Akita mice. Comparative proteomics was performed using label-free proteome expression analysis. Mitochondrial state 3 respirations and ATP synthesis were measured, and mitochondrial morphology was evaluated by electron microscopy. Expression of genes that regulate mitochondrial biogenesis, substrate utilization, and oxidative phosphorylation (OXPHOS) were determined.

RESULTS

In diabetic mice, fatty acid oxidation (FAO) proteins were less abundant in liver mitochondria, whereas FAO protein content was induced in mitochondria from all other tissues. Kidney mitochondria showed coordinate induction of tricarboxylic acid (TCA) cycle enzymes, whereas TCA cycle proteins were repressed in cardiac mitochondria. Levels of OXPHOS subunits were coordinately increased in liver mitochondria, whereas mitochondria of other tissues were unaffected. Mitochondrial respiration, ATP synthesis, and morphology were unaffected in liver and kidney mitochondria. In contrast, state 3 respirations, ATP synthesis, and mitochondrial cristae density were decreased in cardiac mitochondria and were accompanied by coordinate repression of OXPHOS and peroxisome proliferator–activated receptor (PPAR)-γ coactivator (PGC)-1α transcripts.

CONCLUSIONS

Type 1 diabetes causes tissue-specific remodeling of the mitochondrial proteome. Preservation of mitochondrial function in kidney, brain, and liver, versus mitochondrial dysfunction in the heart, supports a central role for mitochondrial dysfunction in diabetic cardiomyopathy.
Short Sleep Duration Is Associated With a Blood Pressure Nondipping Pattern in Type 1 Diabetes
Authors: Borel Anne-Laure , Benhamou Pierre-Yves , Baguet Jean-Philippe , Debaty Isabelle , Levy Patrick , Pépin Jean-Louis , Mallion Jean-Michel
Published: June 2009

OBJECTIVE

To assess whether nocturnal blood pressure dipping status in type 1 diabetes is correlated with specific sleep characteristics and differences in nocturnal glycemic profiles.

RESEARCH DESIGN AND METHODS

Twenty type 1 diabetic adult patients underwent sleep studies with simultaneous 24-h ambulatory blood pressure monitoring and continuous nocturnal glucose monitoring.

RESULTS

Altogether, 55% of patients exhibited blunted blood pressure dipping. They did not differ from the dipper group in age, BMI, or systolic (SBP) and diastolic (DBP) blood pressure. Total sleep period (TSP) was higher in the dipper group (497 ± 30 vs. 407 ± 44 min for dippers and nondippers, respectively, P < 0.001). TSP was correlated with SBP and DBP day-night differences (r = 0.44 and 0.49, respectively). Periods of nocturnal hypoglycemia (i.e., % of TSP with glycemia <70 mg/dl) were longer in the dipper group (8.1 ± 10.7 vs. 0.1 ± 0.4% for dippers and nondippers, respectively, P = 0.02).

CONCLUSIONS

Dipping status in type 1 diabetes was associated with longer sleep duration and with hypoglycemia unawareness.
Sustained Effects of Interleukin-1 Receptor Antagonist Treatment in Type 2 Diabetes
Authors: Larsen Claus M. , Faulenbach Mirjam , Vaag Allan , Ehses Jan A. , Donath Marc Y. , Mandrup-Poulsen Thomas
Published: June 2009

OBJECTIVE

Interleukin (IL)-1 impairs insulin secretion and induces β-cell apoptosis. Pancreatic β-cell IL-1 expression is increased and interleukin-1 receptor antagonist (IL-1Ra) expression reduced in patients with type 2 diabetes. Treatment with recombinant IL-1Ra improves glycemia and β-cell function and reduces inflammatory markers in patients with type 2 diabetes. Here we investigated the durability of these responses.

RESEARCH DESIGN AND METHODS

Among 70 ambulatory patients who had type 2 diabetes, A1C >7.5%, and BMI >27 kg/m2 and were randomly assigned to receive 13 weeks of anakinra, a recombinant human IL-1Ra, or placebo, 67 completed treatment and were included in this double-blind 39-week follow-up study. Primary outcome was change in β-cell function after anakinra withdrawal. Analysis was done by intention to treat.

RESULTS

Thirty-nine weeks after anakinra withdrawal, the proinsulin-to-insulin (PI/I) ratio but not stimulated C-peptide remained improved (by −0.07 [95% CI −0.14 to −0.02], P = 0.011) compared with values in placebo-treated patients. Interestingly, a subgroup characterized by genetically determined low baseline IL-1Ra serum levels maintained the improved stimulated C-peptide obtained by 13 weeks of IL-1Ra treatment. Reductions in C-reactive protein (−3.2 mg/l [−6.2 to −1.1], P = 0.014) and in IL-6 (−1.4 ng/l [−2.6 to −0.3], P = 0.036) were maintained until the end of study.

CONCLUSIONS

IL-1 blockade with anakinra induces improvement of the PI/I ratio and markers of systemic inflammation lasting 39 weeks after treatment withdrawal.
Impact of a Natural Disaster on Diabetes
Authors: Fonseca Vivian A. , Smith Hayden , Kuhadiya Nitesh , Leger Sharice M. , Yau C. Lillian , Reynolds Kristi , Shi Lizheng , McDuffie Roberta H. , Thethi Tina , John-Kalarickal Jennifer
Published: June 2009

OBJECTIVE

To examine the impact of Hurricane Katrina on the health of individuals with diabetes.

RESEARCH DESIGN AND METHODS

This was an observational study in 1,795 adults with an A1C measurement 6 months before and 6−16 months after Hurricane Katrina in three health care systems: private (Tulane University Hospital and Clinic [TUHC]), state (Medical Center of Louisiana at New Orleans [MCLNO]), and Veterans Affairs (VA). Glycemic control (A1C), blood pressure, and lipids before the hurricane were compared with the patients' first measurement thereafter. The CORE Diabetes Model was used to project life expectancy and health economic impact.

RESULTS

Mean predisaster A1C levels differed between MCLNO and VA patients (mean 7.7 vs. 7.3%, P < 0.001) and increased significantly among MCLNO patients to 8.3% (P < 0.001) but not among VA and TUHC patients. Mean systolic blood pressure increased in all three systems (130–137.6 mmHg for TUHC and 130.7–143.7 for VA, P < 0.001; 132–136 for MCLNO, P = 0.008). Mean LDL cholesterol increased in the VA (97.1–104.3 mg/dl) and TUHC patients (103.4–115.5; P < 0.001). Hurricane Katrina increased modeled direct, indirect, and total health care costs and also reduced life expectancy as well as quality-adjusted life expectancy, with the economic impact being quite substantial because of the large population size affected. We estimate a lifetime cost of USD $504 million for the adult population affected, with the largest economic impact seen among MCLNO patients.

CONCLUSIONS

A major disaster had a significant effect on diabetes management and exacerbated existing disparities. These effects may have a lasting impact on both health and economic implications.
Effects of a Protein Preload on Gastric Emptying, Glycemia, and Gut Hormones After a Carbohydrate Meal in Diet-Controlled Type 2 Diabetes
Authors: Ma Jing , Stevens Julie E. , Cukier Kimberly , Maddox Anne F. , Wishart Judith M. , Jones Karen L. , Clifton Peter M. , Horowitz Michael , Rayner Christopher K.
Published: June 2009

OBJECTIVE

We evaluated whether a whey preload could slow gastric emptying, stimulate incretin hormones, and attenuate postprandial glycemia in type 2 diabetes.

RESEARCH DESIGN AND METHODS

Eight type 2 diabetic patients ingested 350 ml beef soup 30 min before a potato meal; 55 g whey was added to either the soup (whey preload) or potato (whey in meal) or no whey was given.

RESULTS

Gastric emptying was slowest after the whey preload (P < 0.0005). The incremental area under the blood glucose curve was less after the whey preload and whey in meal than after no whey (P < 0.005). Plasma glucose-dependent insulinotropic polypeptide, insulin, and cholecystokinin concentrations were higher on both whey days than after no whey, whereas glucagon-like peptide 1 was greatest after the whey preload (P < 0.05).

CONCLUSIONS

Whey protein consumed before a carbohydrate meal can stimulate insulin and incretin hormone secretion and slow gastric emptying, leading to marked reduction in postprandial glycemia in type 2 diabetes.
Simultaneous kinetic spectrophotometric determination of Cu(II), Co(II) and Ni(II) using partial least squares (PLS) regression
Authors: Bahram Morteza , Farhadi Khalil , Afkhami Abbas , Shokatynia Donya , Arjmand Farzin
Published: June 2009

A partial least squares (PLS-1) calibration model based on kinetic—spectrophotometric measurement, for the simultaneous determination of Cu(II), Ni(II) and Co(II) ions is described. The method was based on the difference in the rate of the reaction between Co(II), Ni(II) and Cu(II) ions with 1-(2-pyridylazo)2-naphthol in a pH 5.8 buffer solution and in micellar media at 25°C. The absorption kinetic profiles of the solutions were monitored by measuring the absorbance at 570 nm at 2 s intervals during the time range of 0–10 min after initiation of the reaction. The experimental calibration matrix for the partial least squares (PLS-1) model was designed with 30 samples. The cross-validation method was used for selecting the number of factors. The results showed that simultaneous determination could be performed in the range 0.1-2 μg mL−1 for each cation. The proposed method was successfully applied to the simultaneous determination of Cu(II), Ni(II) and Co(II) ions in water and in synthetic alloy samples.
Kinetics of proton transfer in the zeolitic tuff
Authors: Çakıcıoğlu-Özkan Fehime , Polatoğlu İlker
Published: June 2009

The kinetics of a proton transfer into dilute acid solutions containing natural zeolitic tuff was studied by following the pH evolution of the liquid phase. Four different solutions with tuff contents of 9, 3, 1 and 0.5 (% wt) and three different particle size fractions (≤ 2000 μm) were studied. The proton concentration of the solution was decreased by increasing the zeolite amount and decreasing the particle size fraction. The proton transfer reaction was analyzed with chemical reactions and diffusion model equations. Analysis shows that the adsorption and/or ion exchange are possible mechanisms and are expressed by a second order reaction model.
Interaction of montmorillonite with phenothiazine dyes and pyronin in aqueous dispersions: A visible spectroscopy study
Authors: Czímerová Adriana , Čeklovský Alexander , Bujdák Juraj
Published: June 2009

Layer charge is one of the key parameters used for the characterisation of expandable clay minerals, smectites. It determines most significant properties of the material which are important from the industrial application point of view. This work is related to a novel method introduced to characterize the layer charge of smectites, based on using cationic organic dyes as molecular sensors. One xanthene and four phenothiazine cationic dyes were tested using reduced charge montmorillonites (RCMs) and compared with methylene blue, which has been used most frequently. The characterization of the charge was based on the formation of molecular assemblies (H- and J-aggregates) composed by dye cations, which were easily detectable using absorption spectroscopy in the UV/VIS spectrum. More detailed characterization of the spectra required calculations of second-derivative curves. For all of the reaction systems tested in this work, the molecular aggregation increased with the layer charge of RCMs. Slight to moderate differences in the formation of dye assemblies related to the differences in the molecular structures of the individual dye cations. For example, the molecular asymmetry of azure A brought about the formation of coexistent species of similar structures. The structure of the heteroaromatic skeleton affected the extent of the aggregation and spectral changes with time. The presence of reactive, non-substituted amino groups in thionine cations probably partially decomposed in the clay mineral colloids based on high-charge RCMs. Any of the tested dyes could be used as molecular sensors for empirical characterization of the layer charge of clays taking into account the differences mentioned above.
Photo fenton like process Fe3+/(NH4)2S2O8/UV for the degradation of Di azo dye congo red using low iron concentration
Authors: Devi L. , Kumar S. , Reddy K.
Published: June 2009

Degradation of Congo Red (CR) a di azo dye in aqueous solution is investigated by a Photo Fenton like process using Fe3+ ions as the catalyst and peroxy disulfate as the oxidant. The influence of various reaction parameters like, concentration of Fe3+ ions, concentration of the dye, concentration of ammonium persulfate, pH of the solution and the presence of hydroxyl radical scavenger are studied and optimal conditions are reported. The degradation rate decreased at higher dye concentration and at higher pH. The rate constant (k), catalytic efficiency (kc) and process efficiency (Φ) are evaluated for different concentration of Fe3+ ions. The degradation of CR by the photo Fenton like process leads to the formation of 4-Amino, 3-azo naphthalene sulphonic acid, dihydroxy substituted naphthalene, dihydroxy substituted biphenyl, phenol, quinol etc., as intermediates, based on which probable degradation mechanism is proposed. These results show that a photo Fenton like process could be useful technology for the mineralization of di azo dyes under lower concentration of iron in acidic conditions. The present process is advantageous as it lowers the sludge production resulting from the iron comple
Crystallization of nordstrandite in ethylene glycol / water solutions: electron microscopic studies
Authors: Antunes Maria , Santos Helena , Santos Persio
Published: June 2009

The present work shows the growth of nordstrandite microcrystals observed by transmission and scanning electron microscopy. Nordstrandite was synthesised from non-crystalline aluminium hydroxide reacted in 20% ethylene glycol/water solution, at room temperature. This material was characterized by TEM, SEM, SAED, XRD and EDS/TEM, during six month and revealed the formation and growth of nordstrandite. Fibrillar pseudoboehmite is the only aluminium hydroxide which could be identified during the first two weeks. The nuclei grow, from complete dissolution/recrystallization of pseudoboehmite fibrils, into platy rectangular microscrystals of nordstrandite. Some tabular microcrystals recrystallise, forming after six months only the multi-point nordstrandite stars. This electron-optical study suggest that the star shape results from the overlapping of rectangular plates, and pseudoboehmite fibrils act as the precursor of nordstrandite crystallisation in ethylene glycol/water solution.
Synthesis, characterization and spectroscopic properties of some 2-substituted 1,3-indandiones and their metal complexes
Authors: Ahmedova Anife , Atanasov Vasil , Marinova Petja , Stoyanov Neyko , Mitewa Mariana
Published: June 2009

New 2-acyl-1,3-indandione derivatives, compounds 1–4, were obtained by condensation of 2-acetyl-1,3-indandione with benzaldehyde, thiophene-2-aldehyde, thiophene-3-aldehyde and furane-2-aldehyde, respectively. The structures of the newly synthesized 2-substituted 1,3-indandiones were characterized by means of spectroscopic methods (FT-IR, 1H and 13C NMR, UV-Vis and MS). Based on the obtained results it is suggested that the compounds exist in the exocyclic enolic form. Mass spectral fragmentation paths are also proposed. In order to verify the possibility for tautomerization processes of the newly synthesized compounds their absorption spectra were recorded in various solvents. Furthermore, the complexation properties of the compounds with metal(II) ions were also studied. A series of non-charged complexes with Cu(II), Cd(II), Zn(II), Co(II) and Ni(II) was isolated and analyzed by elemental analyses and IR. The paramagnetic Cu(II) complexes were studied by EPR and distorted, flattened tetrahedral structures are predicted. The other metal complexes show the presence of water molecules, most probably coordinated to the metal ion, thus forming octahedral geometry. Ultimately, the studied properties of the newly synthesized compounds, 1–4, suggest that they may find application as extracting agents for metal ions, rather than as optical sensors.
Stabilization of horseradish peroxidase by covalent conjugation with dextran aldehyde against temperature and pH changes
Authors: Altikatoglu Melda , Arioz Candan , Basaran Yeliz , Kuzu Huriye
Published: June 2009

Stabilization of Horseradish Peroxidase (HRP; EC 1.11.1.7) against temperature and pH via the formation of the conjugates obtained by multipoint covalent bonding of dextran aldehyde (DA) to the enzyme were studied. Hence, three different molar weighted dextrans (17.5 kD, 75 kD, 188 kD) were covalently bonded to purified enzyme with different molar ratios (nHRP/nDA 20/1, 10/1, 1/1, 1/5, 1/10, 1/15, 1/20). The thermal stabilities of the obtained conjugates were evaluated with the activities determined at different temperatures (25, 30, 35, 40, 50, 60, 70, 80°C) applying 60 minutes incubation time. Conjugates formed were characterized by gel-permeation chromatography (GPC) and fluorescence techniques. The conjugate synthesized using dextran 75 kDa with nHRP/nDA 1/10 molar ratio showed better thermal stability than other conjugates and purified enzyme at pH 7. This conjugate also has wider activity pH range than purified enzyme. In addition, mentioned conjugate at pH 7 had very long storage lifetime compared to purified enzyme at +4°C and room temperature; which is considered a favorable feature for usage in practice.
Hydrolysis kinetics of p-nitrophenylpicolinate catalyzed by schiff base Mn(III) complexes in Gemini 16-2-16 micellar solutiony
Authors: Xu Bin , Jiang Weidong , Zhang Jin , Fan Guangyin , Li Jianzhang
Published: June 2009

Two mono-Schiff base Mn(III) complexes (MnL2Cl, L=L1 and L2) were synthesized and employed as artificial hydrolases in catalyzing the hydrolysis of p-nitrophenylpicolinate (PNPP) in Gemini 16-2-16 micellar solution. The effect of different micelles and their complex structures on the catalytic hydrolysis of PNPP is discussed in detail. The observations showed that MnL 22Cl exhibited higher catalytic activity over MnL 12Cl under a comparable condition, which confirmed that an open active centre is essential for modulating the activities of the two enzyme mimics. Moreover, under the conditions employed, hydrolytic rates of PNPP induced by these Mn(III) complexes were faster in Gemini 16-2-16 micelles than that in the micellar solution of cetyltrimethylammonium bromide (CTAB), a conventional analogue of Gemini 16-2-16.
Density functional theory study of the photosensitization mechanisms of indigo
Authors: Ji Hong-Fang , Shen Liang
Published: June 2009

The triplet excited state properties and photosensitization mechanisms of indigo were investigated based on density functional theory calculations. The solvent effects on the photosensitization mechanisms of indigo have also been considered. The thermodynamic feasibility of the possible 1O2 and O2·−-photogeneration pathways by triplet excited state indigo in different solvents was explored, in order to gain some deeper insights into the photosensitization characters of the dye.
Electrochemical study and MO — modeling of the reduction behaviour of some arylidene substituted derivatives of dibenz [b,e]-thiepin-5,5-dioxide-11-one
Authors: Preda Loredana , Volanschi Elena
Published: June 2009

The electrochemical reduction of four arylidene substituted derivatives of dibenz-[b,e]-thiepin-5,5-dioxide-11- one has been studied by cyclic voltammetry on platinum (Pt) electrode in aprotic media (DMSO), coupled with spectral EPR techniques. From the analysis of cyclic voltammetry experiments, aided by digital simulations using DigiSim software, the kinetic and thermodynamic parameters were evaluated for each system. The electrochemical behaviour is strongly directed by the nature of the arylidene substituents bound to the central heterocycle. The electrochemical investigation and solvent dependent semiempirical modeling using the PM3 hamiltonian in the frame of AMPAC program package allowed a rationalisation of experimental data regarding the electrochemical reduction and the reactivity of the intermediate species involved.
Hollow fibre liquid phase microextraction of parabens
Authors: Prichodko Aleksandra , Jonusaite Kristina , Vickackaite Vida
Published: June 2009

A hollow fibre liquid phase microextraction for gas chromatographic determination of some p-hydroxybenzoic acid esters has been developed. Chlorobenzene containing tetradecane as internal standard was used for the extraction. Optimized extraction was carried out at room temperature for 40 min in the presence of 0.4 g mL−1 NaCl in the sample solution. Calibration was linear up to 30 mg L−1. Correlation coefficients were 0.996–0.998. Enrichment factors were 21, 95 and 154, and detection limits were 0.20, 0.03 and 0.01 μg mL−1 for methylparaben, ethylparaben and propylparaben, respectively. Reproducibility was acceptable with relative standard deviations up to 11.7%. The technique was tested for water and urine analysis.
Removal of Pb and Cd from aqueous media and fish liver using novel polyurethane foam functionalized with pyrazolone as a new metal ion collector
Authors: Burham N. , Abdel-Azeem S.M. , El-Shahat M.F.
Published: June 2009

In the present paper, an off-line preconcentration procedure for the determination of cadmium and lead by flame atomic absorption spectrometry (FAAS) is proposed. Polyurethane foam (PUF) functionalized with o-aminophenol (o-AP) followed by Pyrazolone (Pyr) packed in a minicolumn was used as a sorbent material. The metals were retained on the modified PUF, from which it could be eluted and effectively preconcentrated. The detection limits were 0.072 and 0.016 μg L−1 for Pb and Cd respectively. Enrichment factors were 250 and 319 for lead and cadmium respectively. The procedure has been applied successfully to metal determination in water samples, fish liver and reference material.
Sulphur speciation of PM10 samples by XANES spectroscopy
Authors: Cozzi Federico , Pellegrini Italo , Adami Gianpiero , Reisenhofer Edoardo , Bovenzi Massimo , Barbieri Pierluigi
Published: June 2009

Sulphur K-edge X-ray absorption near edge structure (XANES) spectroscopy was used to identify sulphur compounds in PM10 samples collected simultaneously at two sites with different environmental situations in the province of Trieste (NE of Italy), during summer and winter seasons respectively. The first site is an industrial site located near a steel mill plant and the second is a coastal site. The sulphur speciation at the industrial site has shown the presence of the following sulphur compounds in both seasons: organic compounds (thiophenes or Polycyclic Aromatic Sulphur Heterocycles — PAHs) and sulphates while in the winter season sulphites were also present. In the coastal site organic compounds (thiophenes or PASHs) and sulphate were found during winter season, moreover bisulphates were found during summer season. Relative percentages of the different sulphur compounds have shown that sulphate is the most abundant form of sulphur in the industrial site samples during both seasons and in the coastal site sample collected during the winter season (> 98%); in the coastal site sample collected during the summer season the relative percentages of bisulphate and sulphate were around 40% and 60% respectively.
Analytical methods to differentiate Romanian amber and Baltic amber for archaeological applications
Authors: Teodor Eugenia , Liţescu Simona , Neacşu Antonela , Truică Georgiana , Albu Camelia
Published: June 2009

The study aims to establish several definite criteria which will differentiate Romanian amber and Baltic amber to certify the local or Baltic origin of the materials found in archaeological sites on the Romanian territory, by using light microscopy and performing analytical methods, such as Fourier transform infrared spectroscopy-variable angle reflectance and liquid chromatography with mass spectrometry detection. Experiments especially by Fourier transformed infrared spectroscopy, were applied to a wide range of samples with controlled origin. The methods were optimised and resulted in premises to apply the techniques to analysis of the archaeological material.
The effect of layer charge and exchangeable cations on sorption of biphenyl on montmorillonites
Authors: Pálková Helena , Madejová Jana , Komadel Peter
Published: June 2009

Montmorillonies separated from the bentonites SAz-1 (Cheto, AZ, USA), and Cressfield (New South Wales, Australia) were used as starting materials. Reduced charge montmorillonites (RCMs) were prepared from these chemically different and Li-saturated montmorillonites via heating at temperatures in the range of 120–300°C. The residual exchangeable Li+ cations were then replaced with tetramethylammonium (TMA+) or hexadecyltrimethylammonium (HDTMA+) cations and the ability of the modified montmorillonites to adsorb biphenyl was investigated. Lower adsorption was observed for Li-montmorillonites than for the organoclays. The extent of adsorption was dependent on both the layer charge of montmorillonite and the size of alkylammonium cations. HDTMA-forms prepared from unheated Li-montmorillonites adsorbed biphenyl better than the organoclays prepared from RCMs. In contrast, the TMA-samples prepared from the Li-montmorillonites that were not heated showed low uptake of biphenyl probably due to high content of TMA+ cations. Reduction of the layer charge, resulting in lower content of TMA+ cations, increased sorption efficiency of both TMA-montmorillonites. The best adsorbents of biphenyl were HDTMA-SAz-1 prepared from the unheated Li-SAz-1 and TMA-Cressfield prepared from the Li-form heated at 180°C. These samples removed about 80% of biphenyl from its aqueous solutions
Solar-driven electrochemically assisted semiconductor-catalyzed iodide ion oxidation. Enhanced efficiency by oxide mixtures
Authors: Karunakaran Chockalingam , Anilkumar Premkumar
Published: June 2009

Oxidation of iodide ion from an air-saturated solution under natural sunlight (900±50 W m−2) on the surfaces of TiO2, ZnO, Fe2O3, MoO3 and CeO2 enhances by 6 to 12-fold on application of a cathodic bias of −0.2 to −0.3 V (vs NHE) to the semiconductors; light, the semiconductor and dissolved oxygen are essential for iodine generation. The semiconductors under an anodic bias of +0.2 to +0.3 V (vs NHE) fail to oxidize iodide ion from air-saturated solution under sunlight. Under cathodic bias, semiconductor mixtures like TiO2-ZnO, TiO2-Fe2O3 and ZnO-Fe2O3 show enhanced photocatalytic activity, indicating improved charge separation in oxide mixtures. The mechanism of photocatalysis under cathodic bias is discussed.
Determination of p-nitroaniline by the tartrate-acetone-Mn2+-KBrO3-H2SO4 double organic substrate oscillating system using non-equilibrium stationary state
Authors: Gao Jinzhang , Liu Jing , Ren Jie , Niu Xiuli , Zhang Yingying , Yang Wu
Published: June 2009

This paper described the determination of p-nitroaniline in a double organic substrate oscillating system of tartrate-acetone-Mn2+-KBrO3-H2SO4. Under the optimum conditions, temperature was chosen as a control parameter to design the bifurcation point and proposed a convenient method for determination of p-nitroaniline. Results showed that the system consisting of 3.5 mL 0.06 mol L−1 tartrate, 4.0 mL 0.7 mol L−1 H2SO4, 1.5 mL 1.5×10−4 mol L−1 MnSO4, 4.0 mL 0.4 mol L−1 acetone and 7.0 mL 0.05 mol L−1 KBrO3 was very sensitive to the surrounding at 33.5°C. A good linear relationship between the potential difference and the negative logarithm concentration of p-nitroaniline was obtained to be in the range of 2.50×10−7∼3.75×10−5 mol L−1 with a lower detection limit of 2.50×10−8 mol L−1.
Endoparasites of red fox (Vulpes vulpes) in the Slovak Republic with the emphasis on zoonotic species Echinococcus multilocularis and Trichinella spp.
Authors: Miterpáková M. , Hurníková Z. , Antolová D. , Dubinský P.
Published: June 2009

Due to specific geographical localization, climatic and geomorphologic conditions, several serious parasitic diseases circulate in the territory of the Slovak Republic that makes this area an ideal model territory of the central European red fox system. The red fox is an important reservoir host of parasites, which can be spread to another animals and humans. Our study was aimed at determining the current prevalence of certain parasites in red foxes from the entire territory of the Slovak Republic and identifies some ecological factors influencing their epidemiology. Within the first systematic investigation of red foxes carried out between the years 2000 and 2006 in total 4026 foxes were examined for Echinococcus multilocularis (prevalence 31.1 %) and 4699 foxes were investigated for the presence of Trichinella spp. larvae (10.4 % infected). The results of the next separate study revealed that 83.3 % of 1198 red foxes in the Slovak Republic had coccidian oocysts and helminth eggs in their faeces. Fifteen helminth species including two trematode, four cestode and nine nematode species were detected by coprological examination. Nine of these parasite taxa have zoonotic potential: Capillaria spp. (prevalence 22.4 %), Ancylostoma caninum (18.1 %), Toxocara canis (12.5 %), Taenia spp. (12.2 %), Mesocestoides spp. (5.8 %), Strongyloides stercoralis (1.6 %), Hymenolepis diminuta (0.6 %), Dipylidium caninum (0.4 %) and Opisthorchis felineus (0.3 %). Toxascaris leonina was the most common helminth species found in this survey (42.9 %).
Redescription of Desportesius brevicaudatus (Spirurida, Acuariidae) based on nematodes from Ixobrychus minutus (Aves, Ciconiiformes) from Bulgaria
Authors: Mutafchiev Y. , Georgiev B.
Published: June 2009

Desportesius brevicaudatus (Dujardin, 1845) is redescribed on the basis of light-microscopy and SEM observations on specimens collected from the oesophagus and under the lining of the gizzard of Ixobrychus minutus (Ardeidae) from Bulgaria. New metrical data expand the known ranges of variation of the measurements of the body, tail, cordons, oesophagus and spicules. New information is provided on the variation of the shape of the deirids, the structure of the vagina, the complexity of the cordons, the pattern of the cuticular striation and the shape of the postdeirids. Cordons are described as consisting of a single row of serrate cuticular plates and a longitudinal cuticular ridge along the outer rims of the cuticular plates. The cuticular ridge is interpreted as homologous to the outer row of plates in the cordons of the genera Acuaria, Cheilospirura and Echinuria.
Life-cycle of Paracoenogonimus ussuriensis sp. n. (Digenea: Cyathocotylidae) in the Primorsky region (southern Far East, Russia)
Authors: Besprozvannykh V. , Ermolenko A.
Published: June 2009

New cercariae similar to those of Paracoenogonimus (Cyathocotylidae, Prohemistomatinae), have been found in gastropods Amuropaludina and Cipangopaludina from reservoirs of the Primorsky Region (southern Far East of Russia). Two species of freshwater fishes (Pseudorasbora parva and Perccottus glenii) were experimentally-infected second intermediate hosts. Adults reared in chicken, Gallus gallus dom. They belong to a new species, Paracoenogonimus ussuriensis sp. n. They differ from those of P. szidati (Anderson, 1914) and Mesostephanus appendiculatus (Ciurea, 1916) (=P. skworzowi (Petrov, 1950) sensu Sudarikov 1961) by the size of the body, pharynx and ovary and, further, from the latter by the size of the suckers and testes. Adults differ from P. ovatus Katsurada, 1914 by the smaller dimensions of the oral sucker, pharynx and testes, and also by the absence of anterior interval between vitelline follicles.
Soil nematode community changes associated with windfall and wildfire in forest soil at the High Tatras National Park, Slovak Republic
Authors: Čerevková A. , Renčo M.
Published: June 2009

The paper presents research findings on the influence of windfall and wildfire on nematode communities in Lariceto-Piceetum forest in the High Tatras in Slovakia. Comparison was made of an intact (REF), affected and extracted (EXT), non-extracted (NEX) and burnt (FIR) forest stand. A total of 55 species belonging to 36 genera were found. The EXT locality harboured the majority of the identified species, but the highest abundance of nematodes was observed in the FIR locality. Bacterial feeders were the dominant trophic group in all investigated plots. In the REF bacterial feeders were followed by root-fungal feeders, fungal feeders and omnivores, in the EXT by omnivores and plant parasites, in the FIR by omnivores and root-fungal feeders and in the NEX by fungal feeders and omnivores. The MI and SI were higher in the REF and the EXT compared to those in the FIR and the NEX, the highest B/F ratio was observed in the FIR and the highest EI was found in the REF. We can conclude that disturbance of forest vegetation and soil has had a clear and demonstrable impact on nematode communities.
Introductory: Perspectives on Reality and "The World" in the Realism Debate
Authors: Ginev Dimitri
Published: June 2009

Introductory: Perspectives on Reality and "The World" in the Realism Debate

One of the "characteristic parameters" dividing up analytical and Continental philosophizing is the interpretation of the concepts of "reality" and "the world". The paper offers an analysis of this characteristic parameter with regard to the relations between epistemologically centred and hermeneutically oriented doctrines of realism.
Three Things About the Good Life
Authors: Regecová Valéria
Published: June 2009

Three Things About the Good Life
A chemical method of the production of "heavy" sodium tripolyphosphate with the high content of Form I or Form II
Authors: Banach Marcin , Kowalski Zygmunt , Wzorek Zbigniew , Gorazda Katarzyna
Published: June 2009

A chemical method of the production of "heavy" sodium tripolyphosphate with the high content of Form I or Form II

Sodium tripolyphosphate STPP is used in laundry detergent as a detergent "builder". The paper presents the chemical method of obtaining "heavy", i.e. with higher bulk density granulated sodium tripolyphosphate. The bulk density of sodium tripolyphosphate was increased by preparing a mixture of the dried sodium phosphates, the recycled subgrain of STPP and water in specific proportions and calcining this mixture for 1 hour at 400°C and 550°C (to obtain a proper STPP form) in the chamber kiln. This method allows producing the granular sodium tripolyphosphate with high bulk density (1.04-1.07 kg/dm3) and a high content of Form I or Form II, respectively.
Application of pervaporation and osmotic membrane distillation to the regeneration of spent solutions from the osmotic food dehydration
Authors: Kujawski Wojciech , Gierszewska-Drużyńska Magdalena , Warczok Justyna , Güell Carme
Published: June 2009

Application of pervaporation and osmotic membrane distillation to the regeneration of spent solutions from the osmotic food dehydration

Results of pervaporation (PV) of sucrose and calcium chloride spent solutions were presented. Additionally, osmotic membrane distillation (OMD) of sucrose solutions was investigated. It was found that the regeneration of spent sucrose solution for the reuse is possible by using PV or OMD processes. However, OMD process produces another spent stream i.e. CaCl2. Pervaporation membranes showed fluxes in the range of 0.5 - 0.9 kg m-2 h-1 in contact with 40° Brix sucrose solution, whereas OMD water permeate fluxes were in the range of 4 - 5 kg m-2 h-1 for the same feed concentration.

Two different hybrid processes were suggested: i) pretreatment followed by OMD reconcentration of spent sucrose solution and independently PV for CaCl2 regeneration; ii) membrane pretreatment (MP) followed by PV of sucrose solution. Based on the experimental results, the membrane areas for both systems were calculated and compared. MP-PV system seems to be a better solution for the spent mixtures management.
The natural history of untreated sporadic vestibular schwannomas: a comprehensive review of hearing outcomes
Authors: Sughrue Michael E. , Yang Isaac , Aranda Derick , Lobo Khadja , Pitts Lawrence H. , Cheung Steven W. , Parsa Andrew T.
Published: June 2009

Object

Observation is an important consideration when discussing management options for patients with vestibular schwannoma (VS). Most data regarding clinical outcomes after conservative management come from modestsized series performed at individual centers. The authors performed an analysis of the published literature on the natural history of VSs with respect to hearing outcome. Their objective was to provide a comprehensive and unbiased description of outcomes in patients whose disease was managed conservatively.

Methods

The authors identified a total of 34 published studies containing hearing outcome data in patients with VSs < 25 mm in largest diameter who underwent observation management. The effects of initial tumor size and tumor growth rate on hearing function at latest follow-up were analyzed. Data from individual and aggregated cases were extracted from each study. Patients with poorer hearing (American Association of Otolaryngology–Head and Neck Surgery Classes C or D, or Gardner-Robertson Classes III, IV, or V) at the time of presentation were excluded.

Results

A total of 982 patients met the inclusion criteria for this analysis, with a mean initial tumor size of 11.3 ± 0.68 mm. The mean growth rate was 2.9 ± 1.2 mm/year. The length of follow-up for these studies ranged from 26 to 52 months. Patients with preserved hearing at latest follow-up had a statistically larger initial tumor size than those whose hearing declined during the observation period (11.5 ± 2.3 mm vs 9.3 ± 2.7 mm, p < 0.0001), but the 2-mm difference of means was at the limit of imaging resolution and observer reliability. In contrast, patients with lower rates of tumor growth (≤ 2.5 mm/year) had markedly higher rates of hearing preservation (75 vs 32%, p < 0.0001) compared with patients with higher tumor growth rates. Interestingly, the authors' analysis found no difference in the rate of reported intervention for patients in either group (16 vs 18%, p = not significant).

Conclusions

These data suggest that a growth rate of > 2.5 mm/year is a better predictor of hearing loss than the initial tumor size for patients undergoing observation management of VSs < 25 mm in largest diameter.
Termite Resistance of MDF Panels Treated with Various Boron Compounds
Authors: Usta Mustafa , Ustaomer Derya , Kartal Saip Nami , Ondaral Sedat
Published: June 2009

In this study, the effects of various boron compounds on the termite resistance of MDF panels were evaluated. Either borax (BX), boric acid (BA), zinc borate (ZB), or sodium perborate tetrahydrate (SPT) were added to urea-formaldehyde (UF) resin at target contents of 1%, 1.5%, 2% and 2.5% based on dry fiber weight. The panels were then manufactured using 12% urea-formaldehyde resin and 1% NH4Cl. MDF samples from the panels were tested against the subterranean termites, Coptotermes formosanus Shiraki. Laboratory termite resistance tests showed that all samples containing boron compounds had greater resistance against termite attack compared to untreated MDF samples. At the second and third weeks of exposure, nearly 100% termite mortalities were recorded in all boron compound treated samples. The highest termite mortalities were determined in the samples with either BA or BX. Also, it was found that SPT showed notable performance on the termite mortality. As chemical loadings increased, termite mortalities increased, and at the same time the weight losses of the samples decreased.
A Facile Route to C2-Substituted Imidazolium Ionic Liquids
Authors: Ennis Elliot , Handy Scott  T.
Published: June 2009

A convenient route for the preparation of C2-substituted imidazolium ionic liquids is reported. This method involves the alkylation of N-heterocyclic carbenes, which are readily generated from the C2-unsubstituted imidazolium ionic liquids. It works well for non-functionalized alkyl chlorides, and less well for alkyl bromides and iodides, likely due to competing elimination reactions. The resulting C2-substituted salts can be transformed into ionic liquids via standard anion metathesis reactions.
The Effects of Cytokines on Suppression of Lymphocyte Proliferation by Dexamethasone
Authors: Creed Tom J. , Lee Richard W. , Newcomb Paul V. , di Mambro Alexandra J. , Raju Madhuri , Dayan Colin M.
Published: June 2009

Treatment failure occurs in up to 30% of patients treated with steroids for inflammatory diseases. The aim of this study was to explore the potential role of 21 cytokines in steroid-resistant inflammatory disease and to develop methods to restore steroid sensitivity through cytokine manipulation. The dexamethasone inhibition of lymphocyte proliferation assay correlates with the outcome of steroid therapy in ulcerative colitis (UC) and other inflammatory diseases. Using this assay, PBMC production of 21 cytokines, assayed by cytokine bead array, was correlated with percentage of suppression of proliferation by 10−6 M dexamethasone (Imax) in 26 healthy volunteers. Effects of the addition of exogenous cytokines to induce steroid resistance in PBMCs from healthy volunteers and cytokine blockade to improve steroid sensitivity in PBMCs from patients with steroid-resistant UC were then explored. Production of IL-1α, IL-10, IL-17, IFN-γ, G-CSF, GM-CSF, TNF-α, and IFN-inducible protein 10 (IP-10) correlated significantly with in vitro steroid sensitivity; however, only IL-2 and TNF-α reduced steroid sensitivity when added exogenously. Addition of IL-10 enhanced steroid suppression. Immunoneutralization or receptor blockade of IL-2, but not TNF-α, IFN-γ, IL-4, IL-17, or IP-10 increased steroid sensitivity in cells from steroid-resistant UC patients. Neutralization of IL-10 reduced steroid sensitivity. Of the large panel of cytokines studied, IL-2 appears to have the greatest antagonistic effect on the antiproliferative effect of steroids. These data suggest that IL-2 inhibition in vivo may improve the response to steroids in steroid-resistant individuals.
In Vivo Lipopolysaccharide Exposure of Human Blood Leukocytes Induces Cross-Tolerance to Multiple TLR Ligands
Authors: de Vos Alex F. , Pater Jennie M. , van den Pangaart Petra S. , de Kruif Martijn D. , van 't Veer Cornelis , van der Poll Tom
Published: June 2009

In vitro and in vivo experiments in mice have shown that exposure of cells to the TLR4 ligand LPS induces tolerance toward a second exposure to LPS and induces cross-tolerance to certain other TLR ligands. Recently, we found that LPS tolerance in experimental human endotoxemia and Gram-negative sepsis is associated with elevated levels of IL-1R-associated kinase M, an intracellular negative regulator of MyD88-dependent TLR signaling. In the present study, we investigated whether in vivo exposure of humans to LPS induces tolerance in circulating leukocytes to other TLR agonists that rely either on MyD88- dependent or on MyD88-independent signaling. Analysis of TNF, IL-1β, IL-6, and IL-10 levels in whole blood demonstrated that leukocytes were hyporesponsive to ex vivo LPS restimulation 3–8 h after i.v. LPS injection (4 ng/kg). Reduced cytokine release during the same interval was also observed in whole blood further stimulated with MyD88-dependent ligands for TLR2, TLR5, and TLR7 or with whole bacteria. Strikingly, blood leukocytes were also tolerant to a ligand for TLR3, which signals solely through a MyD88-independent (Toll IL-1R domain-containing adaptor-inducing IFN-β (TRIF)-dependent) pathway. The hyporesponsiveness of leukocytes to TLR3 ligation was associated with reduced rather than increased levels of the recently identified TRIF inhibitor SARM. Taken together, these data indicate that systemic LPS challenge of human volunteers induces cross-tolerance to multiple TLR ligands that signal in a MyD88-dependent or MyD88-independent manner and suggest that LPS exposure of human blood leukocytes may hamper the inflammatory response to various microbial components.