bluuebunny/crossref_metadata_2025 huggingface dataset:
New cathinone‐derived designer drugs 3‐bromomethcathinone and 3‐fluoromethcathinone: studies on their metabolism in rat urine and human liver microsomes using GC–MS and LC–high‐resolution MS and their detectability in urine
Authors: Meyer Markus R. , Vollmar Christian , Schwaninger Andrea E. , Wolf Ehud (Udi) , Maurer Hans H.
Published: February 2012

3‐Bromomethcathinone (3‐BMC) and 3‐Fluoromethcathinone (3‐FMC) are two new designer drugs, which were seized in Israel during 2009 and had also appeared on the illicit drug market in Germany. These two compounds were sold via the Internet as so‐called “bath salts” or “plant feeders.” The aim of the present study was to identify for the first time the 3‐BMC and 3‐FMC Phase I and II metabolites in rat urine and human liver microsomes using GC–MS and LC–high‐resolution MS (HR‐MS) and to test for their detectability by established urine screening approaches using GC–MS or LC–MS. Furthermore, the human cytochrome‐P450 (CYP) isoenzymes responsible for the main metabolic steps were studied to highlight possible risks of consumption due to drug–drug interaction or genetic variations. For the first aim, rat urine samples were extracted after and without enzymatic cleavage of conjugates. The metabolites were separated and identified by GC–MS and by LC–HR‐MS. The main metabolic steps were N‐demethylation, reduction of the keto group to the corresponding alcohol, hydroxylation of the aromatic system and combinations of these steps. The elemental composition of the metabolites identified by GC–MS could be confirmed by LC–HR‐MS. Furthermore, corresponding Phase II metabolites were identified using the LC–HR‐MS approach. For both compounds, detection in rat urine was possible within the authors' systematic toxicological analysis using both GC–MS and LC–MSn after a suspected recreational users dose. Following CYP enzyme kinetic studies, CYP2B6 was the most relevant enzyme for both the N‐demethylation of 3‐BMC and 3‐FMC after in vitro–in vivo extrapolation. Copyright © 2012 John Wiley & Sons, Ltd.
2,5‐Piperazinedione inhibits quorum sensing‐dependent factor production in Pseudomonas aeruginosa PAO1
Authors: Musthafa Khadar Syed , Balamurugan Krishnaswamy , Pandian Shunmugiah Karutha , Ravi Arumugam Veera
Published: February 2012

The effects of 2,5‐piperazinedione in reducing the production of quorum sensing (QS)‐dependent factors in Pseudomonas aeruginosa PAO1 were assessed both in vitro and in vivo. 2,5‐Piperazinedione exhibited a 69% reduction in the azocasein‐degrading proteolytic activity and a 48% reduction in the elastolytic activity of PAO1. Further, it showed 85% and 96% reduction in the production of pyocyanin and extracellular polymeric substances (EPS) of PAO1, respectively. In the swimming inhibition assay, 2,5‐piperazinedione‐treated PAO1 cells exhibited poor swimming motility in swim agar medium. In the in vivo analysis, an enhanced survival of PAO1‐preinfected Caenorhabditis elegans was observed after treatment with 2,5‐piperazinedione. Regarding the mode of action, in the molecular docking analysis, 2,5‐piperazinedione interacts with the amino acid residue of the LasR receptor protein required for binding the natural ligand N ‐3‐oxododecanoyl‐l‐homoserine lactone (3‐oxo‐C12‐HSL). This demonstrates the probability of 2,5‐piperazinedione to interfere with the binding process of 3‐oxo‐C12‐HSL to its receptor protein. Thus, the findings of the present study reveal the potential of 2,5‐piperazinedione in reducing the QS‐dependent phenotypic features of PAO1. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Comparative analysis of Campylobacter lari cytolethal distending toxin (CDT) effect on HeLa cells
Authors: Nakajima T. , Hirayama J. , Tazumi A. , Hayashi K. , Tasaki E. , Asakura M. , Yamasaki S. , Moore J. E. , Millar B. C , Matsuda M.
Published: February 2012

We aimed to clarify if Campylobacter lari exerts a cytolethal distending toxin (CDT) effect on HeLa cells. Campylobacter cell lysates (CCLys) from C. jejuni 81–176 and urease‐positive thermophilic Campylobacter (UPTC) CF89‐12 and UPTC NCTC12893 isolates were shown to exert a CDT effect on HeLa cells with morphological changes examined by Giemsa staining and microscopy. However, Campylobacter lari JCM2530T isolate showed no effect. In addition, Campylobacter cell culture supernatant wash gave low or absent toxic effects with both C. jejuni and C. lari organisms. When western blot analysis was carried out to clarify if there was a CDTB effect in the CCLys and soluble fractions from Campylobacter isolates, which had a CDT effect on HeLa cells or did not have any effect, anti‐recombinant CjCDTB antibodies identified an immunoreactively positive signal at around approximately 25 kDa on all the C. lari isolates examined, as well as the C. jejuni 81116 strain. Thus, all the Campylobacter isolates including those without any CDT effect were shown to express CDTB at the translational level. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Purification and characterization of a highly thermostable esterase from the actinobacterium Geodermatophilus obscurus strain G20
Authors: Jaouani Atef , Neifar Mohamed , Hamza Adnen , Chaabouni Semia , Martinez Maria Jesus , Gtari Maher
Published: February 2012

Intracellular thermostable esterase produced by the extremophilic Geodermatophilus obscurus G20 was purified to homogeneity by a heat treatment, followed by an anion‐exchange chromatography, and then characterized. The molecular weight of the purified enzyme determined by sodium dodecyl sulfate‐polyacrylamide gel electrophoresis (SDS‐PAGE) was shown to be approximatively 55 kDa. The enzyme showed an optimal activity between pH 8.0 and 9.0 and was stable in the pH range 7.0–10.0. Moreover, it is highly thermostable, with a residual activity greater than 90% after incubation at 80 °C for more than 10 h. The enzyme showed preference for esters of p ‐nitrophenol with short chain fatty acid. When the p ‐nitrophenyl acetate (C2) was used as substrate, the Michaelis–Menten constant (Km) and maximum velocity for the reaction (Vmax) of esterase were 400 μM and 2500 U/mg protein, respectively. The effect of phenylmethanesulphonyl fluoride (PMSF), a serine‐specific inhibitor, on the enzyme activity suggested that the thermostable esterase belong to the serine hydrolase group. Because of its high thermostability, activity at alkaline pH, tolerance to methanol and various metal ions and specificity for short chain fatty acids, this enzyme showed high potential for use in biocatalysis. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Statistical optimization of medium components for production of extracellular chitinase byBasidiobolus ranarum: a novel biocontrol agent against plant pathogenic fungi
Authors: Mishra P. , Kshirsagar P. R. , Nilegaonkar S. S. , Singh S. K.
Published: February 2012

The influence of concentration of medium components such as colloidal chitin, lactose, malt extract, yeast extract, and peptone on the chitinase production fromBasidiobolous ranarumat the flask level were studied by using statistical tool Central Composite Design (CCD) and analysed by Response Surface Methodology (RSM). The results revealed that colloidal chitin, malt extract and peptone had significant effect (P< 0.01) on the chitinase production at their individual levels. The polynomial equation of the model developed incorporates 3 linear, 3 quadratic and 5 interactive terms. Maximum chitinase production of 3.47 U ml–1was achieved with 1.5% colloidal chitin, 0.125% lactose, 0.025% malt extract and 0.075% peptone. After optimization, chitinase activity was increased by 7.71 fold. A second order polynomial equation was found to be useful for the development of efficient bioprocess for chitinase production. To screen the biotechnological potential of this enzyme, degradation of fungal mycelia by ammonium sulphate precipitate of the same was studied for several pathogenic fungi‐in vitrowhich showed promising results particularly againstRhizoctonia solaniandFusarium solani. This study provides the first evidence showing the effectiveness of RSM for the development of a robust statistical model for the chitinase production byBasidiobolusand for its application in the biocontrol of phytopathogenic fungi. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Bird assemblages of intensively established pine plantations in Coastal Plain Mississippi
Authors: Hanberry Brice B. , Hanberry Phillip , Riffell Samuel K. , Demarais Stephen , Jones Jeanne C.
Published: February 2012

Pine (Pinusspp.) plantations are a common type of managed forest in the southeastern United States that may supply habitat for early successional bird species, many of which are declining. To provide information about young pine plantations as bird habitat, we evaluated spring bird presence in 5 combinations of stand establishment practices during years 2 through 5 post‐establishment in the Lower Coastal Plain of Mississippi, USA. We detected 38 species with point counts and compared bird metrics among establishment practices using mixed general linear models. Species richness, total relative abundance, and relative abundance of many species were greater by at least a factor of 1.5–4 in the chemical‐only establishment practice than mechanically prepared establishment practices, and values declined by about 5–60% within mechanically prepared establishment practices as herbicide intensity increased. Tree and snag retention contributed to avian abundance and richness in the chemical‐only establishment practice. Our study, in conjunction with past research, demonstrated the conservation value to early successional bird species of managed pine stands established with tree retention, indicating that silvicultural and wildlife habitat objectives can be met within the range of stand establishment treatments available to managers. © 2012 The Wildlife Society.
Determination of rate parameters based on both direct and indirect measurements
Authors: Turányi T. , Nagy T. , Zsély I. Gy. , Cserháti M. , Varga T. , Szabó B. T. , Sedyó I. , Kiss P. T. , Zempléni A. , Curran H. J.
Published: February 2012

The determination of rate parameters of gas‐phase elementary reactions is usually based on direct measurements. The rate parameters obtained in many independent direct measurements are then used in reaction mechanisms, which are tested against the results of indirect experiments, like time‐to‐ignition or laminar flame velocity measurements. We suggest a new approach that takes into account both direct and indirect measurements and optimizes all influential rate parameters. First, the domain of feasibility of the Arrhenius parameters is determined from all of the available direct measurements. Thereafter, the optimal Arrhenius parameters are sought within this domain to reproduce the selected direct and indirect measurements. Other parameters of a complex mechanism (third‐body efficiencies, enthalpies of formation, parameters of pressure dependence, etc.) can also be taken into account in a similar way. A new fitting algorithm and a new method for error calculation were developed to determine the optimal mean values and the covariance matrix of all parameters. The approach is demonstrated on the calculation of Arrhenius parameters of reactions (R1): H + O2 = OH + O and (R2): H + O2 + M = HO2 + M (low‐pressure limit, M = N2 or Ar). In total, 9 direct measurements for reaction (R1) (745 data points), 10 direct measurements for reaction (R2) (258 data points), and 11 ignition time measurements (79 data points) were taken into account. The application of the method resulted in the following rate parameters for the investigated reactions—(R1): A = 3.003 × 1010 cm3 mol−1 s−1, n = 0.965, E/R = 6158 K (T = 950–3550 K) and (R2): A = 7.856 × 1018 cm6 mol−2 s−1, n = −1.100, E/R = 0 K (low‐pressure limit, M = N2, T = 300–1850 K). The optimized third‐body efficiency of Ar relative to N2 is m = 0.494 (standard deviation σ = 0.010). The uncertainty parameter f as a function of temperature was also calculated. Average uncertainty parameter values are f = 0.025 and 0.049 for reactions (R1) and (R2) (corresponding to 6% and 12%), respectively, which are much lower than those of the previous evaluations. © 2012 Wiley Periodicals, Inc. Int J Chem Kinet 44: 284–302, 2012
Application of Low‐Level Laser Therapy for Noninvasive Body Contouring
Authors: Jackson Robert F. , Stern Fredric A. , Neira Rodrigo , Ortiz‐Neira Clara L. , Maloney Jillian
Published: February 2012

Background

Low‐level laser therapy (LLLT) is a noninvasive treatment for a wide‐assortment of medical ailments. A recent application is for noninvasive body slimming. A Level 1 clinical study was completed and recorded a significant reduction in circumferential measurements across waist, hips, and thighs compared to placebo subjects. Questions remain unanswered to whether the result observed was based upon simple fluid redistribution. The purpose of this retrospective study was to evaluate the efficacy of LLLT for noninvasive body slimming and determine if the loss was attributable to fluid or fat relocation.

Methods

Data from 689 participants were obtained to evaluate the circumferential reduction demonstrated across the treatment site of the waist, hips, and thighs as well as nontreated systemic regions. Patient data were not pre‐selected; all reports provided by clinics using LLLT for body contouring were used to evaluate the efficacy of this treatment. Participants received a total of six LLLT treatments across 2‐weeks having baseline and post‐procedure circumferential measurements recorded. Measurement sites included waist, hips, thighs, arms, knees, neck, and chest.

Results

The mean circumferential reduction reported for the waist, hips, and thighs 1 week after the treatment regimen was 3.27 in. (P < 0.0001). Furthermore, participants demonstrated an overall mean reduction of 5.17 in. across all measurement points 5.17 in. (P < 0.0001). Each anatomical region measured exhibited a significant circumferential reduction.

Conclusion

These data reveal that the circumferential reduction exhibited following LLLT is not attributable to fluid or fat relocation as all measurement points, including nontreated regions, reported an inch loss. Lasers Surg. Med. 44:211–217, 2012. © 2012 Wiley Periodicals, Inc.
Double Pass 595 nm pulsed dye laser at a 6 minute interval for the treatment of port‐wine stains is not more effective than single pass
Authors: Peters M.A.D. , van Drooge A.M. , Wolkerstorfer A. , van Gemert M.J.C. , van der Veen J.P.W. , Bos J.D. , Beek J.F.
Published: February 2012

Background

Pulsed dye laser (PDL) is the first choice for treatment of port wine stains (PWS). However, outcome is highly variable and only a few patients achieve complete clearance. The objective of the study was to compare efficacy and safety of single pass PDL with double pass PDL at a 6 minute interval.

Methods

We conducted a randomized within‐patient controlled study on PWS resistant to multiple single pass PDL treatments. In each patient two similar PWS areas were randomly allocated to PDL treatment (595 nm, 7 mm spot size, 1.5 mseconds pulse duration) using, as a control treatment, a single pass (12 J/cm2) or, as a new treatment, a double pass PDL (11 J/cm2, second pass 6 minutes after the first pass). Both test areas were treated two times, 8 weeks apart. PWS clearance was assessed by two blinded dermatologists, and by color measurement (L*a*b) using reflectance spectroscopy, at 3 months follow‐up.

Results

Sixteen out of 17 included patients completed follow‐up. The mean number of treatments before inclusion was 15. Overall color assessed by spectrophotometer showed no improvement for either single or double pass PDL. Blinded Physician Global Assessment and Patient Global Assessment showed a high variability in outcome, with mostly only moderate improvement of the PWS for either single pass or double pass PDL. Furthermore, there was no significant difference in any of the outcomes between single pass and double pass PDL.

Conclusion

At the chosen settings and after two treatment sessions, double pass PDL at a 6 minute interval does not result in improved clearance of PWS as compared to single pass treatment. Lasers Surg. Med. 44:199–204, 2012. © 2012 Wiley Periodicals, Inc.
Novel Biodegradable and pH‐Sensitive Poly(ester amide) Microspheres for Oral Insulin Delivery
Authors: He Pan , Tang Zhaohui , Lin Lin , Deng Mingxiao , Pang Xuan , Zhuang Xiuli , Chen Xuesi
Published: February 2012

Biodegradable and pH‐sensitive PEAs based on dual amino acids are designed, synthesized, and characterized. Insulin can be loaded into the PEA microspheres by a solid‐in‐oil‐in‐oil technique with high encapsulation efficiency. The feasibility of PEA microspheres as oral insulin delivery carriers is evaluated in vitro and in vivo. The hydrophobic leucine groups on PEA seem to play an important role in the pH‐dependent release mechanism and cytotoxicity of PEA microspheres. Oral administration of insulin‐loaded PEA microspheres to streptozotocin‐induced diabetic rats at 60 IU kg−1 is able to reduce fasting plasma glucose levels to 49.4%. These results indicate that PEA microspheres are potential new vehicles for insulin oral delivery.

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Comparison of Scheffersomyces stipitis strains CBS 5773 and CBS 6054 with regard to their xylose metabolism: implications for xylose fermentation
Authors: Krahulec Stefan , Kratzer Regina , Longus Karin , Nidetzky Bernd
Published: February 2012

The various strains of Scheffersomyces stipitis (Pichia stipitis) differ substantially with respect to their ability to ferment xylose into ethanol. Two P. stipitis strains CBS 5773 and CBS 6054 have been most often used in literature but comparison of their performance in xylose fermentation under identical conditions has not been reported so far. Conversion of xylose (22 g/L) by each of these P. stipitis strain was analyzed under anaerobic and microaerobic conditions. Ethanol yields of ∼0.41 g/g were independent of strain and conditions used. Glycerol and acetate were formed in constant yields of 0.006 g/g and 0.02 g/g, respectively. Xylitol formation decreased from ∼0.08 g/g to ∼0.05 g/g upon switch from anaerobic to microaerobic conditions. Specific activities of enzymes of the two‐step oxidoreductive xylose conversion pathway (xylose reductase and xylitol dehydrogenase) matched for both strains within limits of error. When xylose was offered at 76 g/L under microaerobic reaction conditions, ethanol yields were still high (0.37–0.39 g/g) for both strains even though the xylitol yields (0.12–0.13 g/g) were increased as compared to the conditions of low xylose concentration. P. stipitis strains CBS 5773 and CBS 6054 are therefore identical by the criteria selected and show useful performance during conversion of xylose into ethanol, irrespective of the supply of oxygen.
Intrathecal application of autologous bone marrow cell preparations in parkinsonian syndromes
Authors: Storch Alexander , Csoti Ilona , Eggert Karla , Henriksen Tove , Plate Annika , Lorrain Michael , Oertel Wolfgang H. , Antonini Angelo
Published: February 2012

Background:

A growing number of patients is treated with intrathecal application of autologous bone marrow cells (aBMCs), but clinical data are completely lacking in movement disorders. We provide first clinical data on efficacy and safety of this highly experimental treatment approach in parkinsonian syndromes.

Methods:

Retrospective data collection from patients with parkinsonism who spontaneously sought cell treatment. The application procedure was neither recommended nor performed by the authors.

Results:

We report 17 patients with parkinsonian syndromes (Parkinson's disease [PD], n = 7; multiple system atrophy [MSA], n = 7; various, n = 3) who received intrathecal application of aBMCs. We did not observe any changes in motor function, activities of daily living, global clinical impression, or antiparkinsonian medication after a median observation period of 10 months. Two patients reported a worsening of parkinsonian symptoms, but the intervention was otherwise safe and well‐tolerated.

Conclusions:

Intrathecal application of aBMCs in uncontrolled conditions produces no clinical benefit in parkinsonian syndromes. © 2012 Movement Disorder Society
Concordance and consistency of answers to the self‐delivered ESPAD questionnaire on use of psychoactive substances
Authors: Molinaro Sabrina , Siciliano Valeria , Curzio Olivia , Denoth Francesca , Mariani Fabio
Published: February 2012

Considering the prevalence of drug use in Italy, it is crucial to develop a reproducible screening test. Test–retest reliability and internal consistency are important indicators of a measurement's temporal stability and are a necessary condition for validity. The aim of the study was to assess the consistency and concordance of the European School Survey Project on Alcohol and Other Drugs (ESPAD) questionnaire; participating students completed the questionnaire twice, with a three‐week interval. To verify the concordance for variables relating to use of alcohol, cigarettes and illicit drugs, the original ordinal variables as well as the same dichotomically recodified variables were used. Data analysis was done using Kappa and weighted Kappa. The method proposed by Lipsitz was used to evaluate the influence of gender and age on concordance. Questions about drug use, examined in ordinal form, show a good test–retest concordance and an excellent concordance for answers relating to the use of cigarettes, alcohol and cannabis. Regarding the effect of age adjusted for gender, 15‐year‐old subjects showed a lower concordance than 19‐year‐olds. ESPAD is a tool with a good reproducibility. Results focus on the effect of gender and age covariates on the concordance of answers regarding drug use and suggest the importance of examining the concordance in relation to the covariate levels. Copyright © 2012 John Wiley & Sons, Ltd.
Retrospective image correction in the presence of nonlinear temporal magnetic field changes using multichannel navigator echoes
Authors: Versluis M. J. , Sutton B. P. , de Bruin P. W. , Börnert P. , Webb A. G. , van Osch M. J.
Published: February 2012

Spatio‐temporal magnetic field changes in the brain caused by breathing or body movements can lead to image artifacts. This is especially a problem in T2*‐weighted sequences. With the acquisition of an extra echo (navigator), it is possible to measure the magnetic field change induced frequency offset for a given slice during image acquisition. However, substantial local variation across a slice can occur. This work describes an extension of the conventional navigator technique that improves the estimation of the magnetic field distribution in the brain during strong field fluctuations. This is done using the combination of signals from multiple coil elements, the coil sensitivity profiles, and frequency encoding: termed sensitivity‐encoded navigator echoes. In vivo validation was performed in subjects who performed normal breathing, nose touching, and deep breathing during scanning. The sensitivity‐encoded navigator technique leads to an error reduction in estimating the field distribution in the brain of 73% ± 16% compared with 56% ± 14% for conventional estimation. Image quality can be improved via incorporating this navigator information appropriately into the image reconstruction. When the sensitivity‐encoded navigator technique was applied to a T2*‐weighted sequence at 7 T, a ghosting reduction of 47% ± 13% was measured during nose touching experiments compared with no correction. Magn Reson Med, 2012. © 2012 Wiley Periodicals, Inc.
Phosphonate‐terminated poly(vinyl acetate) synthesized by RAFT/MADIX polymerization
Authors: Dufils P‐E. , David G. , Boutevin B. , Woodward G. , Otter G. , Guinaudeau A. , Mazières S. , Destarac M.
Published: February 2012

Four different xanthates containing either phosphonate or bisphosphonate moieties were synthesized with high degree of purity. These xanthates were used as chain transfer agents (CTA) in the RAFT/MADIX polymerization of vinyl acetate (VAc) to prepare end‐capped poly(VAc). The rate of VAc polymerization in the presence of these new CTAs was shown to be similar to that obtained with conventional xanthate, that is, (methyl ethoxycarbonothioyl) sulfanyl acetate. Good control of VAc polymerization was also obtained since the molecular weight increased linearly with monomer conversion for each phosphonate‐containing xanthate. Low‐PDI values were obtained, ascribed to efficient exchange during RAFT/MADIX polymerization. Cex value was therefore calculated to about 25, based on RAFT/MADIX of VAc in the presence of rhodixan A1/VAc adduct. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Synthesis, characterization, and micellization of PCL‐g‐PEG copolymers by combination of ROP and “Click” chemistry via “Graft onto” method
Authors: Zhang Kai , Wang Ying , Zhu Weipu , Li Xiaodong , Shen Zhiquan
Published: February 2012

Biodegradable and biocompatible PCL‐g‐PEG amphiphilic graft copolymers were prepared by combination of ROP and “click” chemistry via “graft onto” method under mild conditions. First, chloro‐functionalized poly(ε‐caprolactone) (PCL‐Cl) was synthesized by the ring‐opening copolymerization of ε‐caprolactone (CL) and α‐chloro‐ε‐caprolactone (CCL) employing scandium triflate as high‐efficient catalyst with near 100% monomer conversion. Second, the chloro groups of PCL‐Cl were quantitatively converted into azide form by NaN3. Finally, copper(I)‐catalyzed cycloaddition reaction was carried out between azide‐functionalized PCL (PCL‐N3) and alkyne‐terminated poly(ethylene glycol) (A‐PEG) to give PCL‐g‐PEG amphiphilic graft copolymers. The composition and the graft architecture of the copolymers were characterized by 1H NMR, FTIR, and GPC analyses. These amphiphilic graft copolymers could self‐assemble into sphere‐like aggregates in aqueous solution with diverse diameters, which decreased with the increasing of grafting density. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Diene‐based polymer nanoparticles: Preparation and direct catalytic latex hydrogenation
Authors: Wang Hui , Pan Qinmin , Rempel Garry L.
Published: February 2012

The diene‐based polymer nanoparticles represented by poly(butadiene‐co‐acrylonitrile) were prepared in the semibatch emulsion polymerization system using Gemini surfactant (GS) trimethylene‐1,3‐bis(dodecyldimethylammonium bromide) as the emulsifier. The nanoparticles within the range of 17–54 nm were achieved with narrow molecular weight and particle size distributions. A spherical morphology was observed for the produced nanoparticles. The effects of GS concentration on the particle size, molecular weight, polymerization conversion and solid content, and composition of copolymer were investigated. The semibatch process using monomeric and conventional surfactant sodium dodecyl sulfate (SDS) was compared. At the second stage of this study, the prepared unsaturated nanoparticles were employed as the substrates for the latex hydrogenation in the presence of Wilkinson's catalyst, that is, RhCl(P(C6H5)3)3. The effects of the particle size and catalyst concentration on the latex hydrogenation rate were investigated. The particle size is found to have a significant effect on the reaction rate. When the 17‐nm nanoparticles were used as the substrates, a high conversion of 95 mol % was obtained within 18 h using only 0.1 wt % RhCl(P(C6H5)3)3. The latex hydrogenation process was completely free of organic solvents. The present synthesis and following “green” hydrogenation process can be extended to latices made from semibatch emulsion containing other diene‐based polymers. This study shows great promise for decreasing the demanded quantity of expensive catalyst and eliminating the organic solvent in the hydrogenation process. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
AGET ATRP of water‐soluble PEGMA: Fast living radical polymerization mediated by iron catalyst
Authors: Miao Jie , He Weiwei , Zhang Lifen , Wang Yi , Cheng Zhenping , Zhu Xiulin
Published: February 2012

In this work, living radical polymerizations of a water‐soluble monomer poly(ethylene glycol) monomethyl ether methacylate (PEGMA) in bulk with low‐toxic iron catalyst system, including iron chloride hexahydrate and triphenylphosphine, were carried out successfully. Effect of reaction temperature and catalyst concentration on the polymerization of PEGMA was investigated. The polymerization kinetics showed the features of “living”/controlled radical polymerization. For example, Mn,GPC values of the resultant polymers increased linearly with monomer conversion. A faster polymerization of PEGMA could be obtained in the presence of a reducing agent Fe(0) wire or ascorbic acid. In the case of Fe(0) wire as the reducing agent, a monomer conversion of 80% was obtained in 80 min of reaction time at 90 °C, yielding a water‐soluble poly(PEGMA) with Mn = 65,500 g mol−1 and Mw/Mn = 1.39. The features of “living”/controlled radical polymerization of PEGMA were verified by analysis of chain‐end and chain‐extension experiments. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
New selenium‐based iniferter agent for living free radical polymerization of styrene under UV irradiation
Authors: Zeng Jindong , Zhu* Jian , Zhang Zhengbiao , Pan Xiangqiang , Zhang Wei , Cheng Zhenping , Zhu* Xiulin
Published: February 2012

P,P‐Diphenyl phosphinodiselenoic acid benzyl ester was synthesized and used as a mediator for the polymerization of styrene under UV–vis irradiation. Moderately controlled evidence was found: linear polymerization kinetics, linear evolution of molecular weight with monomer conversion, and relatively narrow molecular weight distribution (1.5–2.0). The structure of the obtained polymers was characterized using NMR and oxidative eliminaton. Based on polymerization results, an iniferter mechanism was proposed for the current polymerization system. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Monte carlo simulations of polydisperse polymers grafted on spherical surfaces
Authors: Dodd Paul M. , Jayaraman Arthi
Published: February 2012

This article presents effects of polydispersity in polymers grafted on spherical surfaces on grafted polymer chain conformations, grafted layer thickness, and free‐end monomer distribution within the grafted layer. At brush‐like grafting densities, as polydispersity index (PDI) increases, the scaling exponent of radius of gyration of grafted chains approaches that of a single chain grafted on the same nanoparticle, because polydispersity alleviates monomer crowding within the brush. At high PDI, the chains shorter than the number average chain length, Nn, have more compressed conformations, and the chains longer than Nn overall stretch less than in the monodisperse case. As seen in polydisperse flat brushes at high grafting densities, the grafted layer thickness on spherical nanoparticle increases with PDI. Polydispersity eliminates the region near the surface devoid of free‐end monomers seen in monodisperse cases, and it reduces the width of free‐end monomer distribution and shifts the free‐end monomer distribution close to the surface. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012
Parthenolide Inhibits the LPS‐induced Secretion of IL‐6 and TNF‐α and NF‐κB Nuclear Translocation in BV‐2 Microglia
Authors: Magni Paolo , Ruscica Massimiliano , Dozio Elena , Rizzi Eleonora , Beretta Giangiacomo , Facino Roberto Maffei
Published: February 2012

Feverfew (Tanacetum parthenium [L.] Sch. Bip. [Asteraceae]) is a popular herbal treatment used to prevent and treat headache and migraine. Parthenolide (PTN), the sesquiterpene lactonic derivative that is the plant's major component, might be one of the ingredients that act on mediators of inflammation. In the present study, in cultured lipopolysaccharide (LPS)‐stimulated BV‐2 microglia pretreatment with PTN caused a dose‐dependent reduction of interleukin‐6 (IL‐6) secretion (29% by 200 nm, p < 0.001; 45% by 1 µm, p < 0.001; 98% by 5 µm, p < 0.001); at 5 µm, the highest concentration tested, it also reduced the secretion of TNF‐α (54%, p < 0.001). Western blotting analysis on separate cytoplasmic and nuclear extracts showed that PTN strongly reduced the translocation of nuclear factor (NF)‐κB to the cell nucleus. The reduction of microglial activation by inhibition of proinflammatory agents may help attenuate the onset and intensity of acute migraine attacks. These in vitro results provide an additional explanation for the efficacy of orally administered T. parthenium as an antimigraine agent. Copyright © 2012 John Wiley & Sons, Ltd.
Comfrey: A Clinical Overview
Authors: Staiger Christiane
Published: February 2012

Comfrey has a centuries‐old tradition as a medicinal plant. Today, multiple randomized controlled trials have demonstrated the efficacy and safety of comfrey preparations for the topical treatment of pain, inflammation and swelling of muscles and joints in degenerative arthritis, acute myalgia in the back, sprains, contusions and strains after sports injuries and accidents, also in children aged 3 or 4 and over. This paper provides information on clinical trials and non‐interventional studies published on comfrey to date and further literature, substantiating the fact that topical comfrey preparations are a valuable therapy option for the treatment of painful muscle and joint complaints. Copyright © 2012 John Wiley & Sons, Ltd.
Extracts from Radix Astragali and Radix Rehmanniae Promote Keratinocyte Proliferation by Regulating Expression of Growth Factor Receptors
Authors: Ren J. W. , Chan K. M. , Lai Patrick K. K. , Lau Clara B. S. , Yu H. , Leung P. C. , Fung K. P. , Yu Walter F. X. , Cho C. H.
Published: February 2012

Chinese herbal medicine has long been used as a treatment for wounds. However, the underlying cellular and molecular mechanisms remain largely unknown. In this study it was shown that the proliferation of keratinocytes, which is known to play an important role in wound healing as the major cell type in the epidermis, was promoted by three herbal extracts/natural compounds: NF3 (an extract from the mixture of Radix Astragali (RA) and Radix Rehmanniae (RR) in the ratio of 2:1), stachyose (an isolated compound from Radix Rehmanniae) and extract P2‐2 (a sub‐fraction from the extract of Radix Astragali). The effect of the herbal extracts/natural compounds on the growth of keratinocytes was not influenced by a high glucose level, a condition similar to diabetic patients who usually suffer from diabetic foot ulcers. Real time RT‐PCR results showed that the expression of epidermal growth factor (EGF) receptor, but not transforming growth factor‐β (TGF‐β) receptor, was up‐regulated by NF3. Moreover, treatments with the EGF receptor kinase inhibitor AG1478 and the MEK inhibitor U0126 resulted in the diminishment of the effect of the three herbal extracts/natural compounds on keratinocyte proliferation, indicating that EGF receptor might have a significant role in this action. This study has further elucidated the molecular mechanism under which herbal extracts/natural compounds exert their effects on the wound healing process. Copyright © 2012 John Wiley & Sons, Ltd.
Vibrational analysis beyond the harmonicity from Ab initio molecular dynamics: Case of cytosine in its anhydrous and aqueous forms
Authors: Carbonniere Philippe , Thicoipe Sandrine , Very Thibault , Assfeld Xavier
Published: February 2012

This study provides the set of theoretical anharmonic fundamental transitions for cytosine in its anhydrous and hydrated forms from a vibrational analysis issuing from a time‐dependent approach. This evaluation is compared to the time‐independent VPT2 approach and to the experimental data available in the literature for the two forms. To investigate the vibrational property of a solute in a polar protic solvent, that is, the aqueous form of cytosine in this particular case, a practicable computational strategy to properly take into account the solvent effect is proposed. This is done by considering a combination of polarizable continuum model and of discrete solvent molecules model. The number of solvent molecules was chosen in such a way that the solute–solvent complex presents only one dominant stable conformer at 298 K. The quality of this combined solvent model is illustrated by comparing the structural and anharmonic vibrational properties achieved with those obtained from a purely implicit and purely explicit solvent model. © 2012 Wiley Periodicals, Inc. Int J Quantum Chem, 2012
Basis set and functional effects on excited‐state properties: Three bicyclic chromogens as working examples
Authors: Jacquemin Denis , Adamo Carlo
Published: February 2012

We have computed, at the time‐department density functional theory, TD‐DFT level of approximation, the ground‐ and excited‐state properties of three typical chromophores, namely indole, coumarin, and benzofurazan, using six functionals (B3LYP, B3P86, PBE0, BMK, BH&HLYP, and CAM‐B3LYP) and four atomic basis sets (BSs), the larger being 6‐311++G(2d,2p). It turned out that diffuse functions are necessary to obtain correct vertical transition energies. The selected functional mainly impacts on these energies, but the differences of vibrational energies between the ground‐ and excited‐states are almost BS and functional independent. The adiabatic gap estimated with total energies or with Gibbs free enthalpies are nearly the same provided the ZPVE effects are accounted for. Int J Quantum Chem, 2012. © 2012 Wiley Periodicals, Inc.
The adiabatic‐to‐diabatic transformation angle and topological phases for strongly interacting states: Solution with four states
Authors: Das Anita , Mukhopadhyay Debasis
Published: February 2012

A few years back T. Vértesi et al. (J Phys Chem A 2005, 109, 3476) gave an elegant procedure to derive the adiabatic‐to‐diabatic transformation angle (ADT‐angle) for lowest two states, γ12, in presence of their interaction with the higher states. In this article, we explicitly solved the coupled differential equations involving the ADT‐angles describing the mixing of four interacting states for the first time to get all the ADT‐angles, γij's (including the γ12) associated with well‐defined topological phases. In application to a suitable configuration space (CS) of a molecular system, we have demonstrated well‐defined Berry phases (Berry M. V., R Soc London Ser A 1984, 45, 392) for an isolated system with as many as four strongly interacting states. © 2012 Wiley Periodicals, Inc.
Theoretical study on a series of push–pull molecules grafted on methacrylate copolymers serving for nonlinear optics
Authors: Derrar S. N. , Sekkal‐Rahal M. , Guemra K. , Derreumaux P.
Published: February 2012

The B3LYP functional combined with 6‐31G(d) basis set have been designated as the most appropriate for structural investigations of a new range of organic conjugated push–pull molecules containing numerous electron donor/acceptor couples in their ends. Second‐order Møller Plesset has been used to properly reproduce nonlinear optical (NLO) properties and to study the alkyl chain length effect of these systems. Satisfactory dynamic hyperpolarizabilities at the wavelength 1064 nm are obtained with values in the order of 11,500 × 10−30 esu. Then, the study has been extended to monomers generated by combination of the chromophores to either acryloyl chloride or 4‐hydroxy‐styrene sequences. Then, the obtained molecules have been grafted to a methyl methacrylate copolymeric chain, the resulting values of β(1064 nm) have been demonstrated to be sensitive to these modifications. © 2012 Wiley Periodicals, Inc. Int J Quantum Chem, 2012
Path integral approach to the calculation of reaction rates for a reaction coordinate coupled to a dual harmonic bath
Authors: Yang Yonggang , Kühn Oliver
Published: February 2012

We present a new method for the numerical calculation of canonical reaction rate constants in complex molecular systems, which is based on a path integral formulation of the flux–flux correlation function. Central is the partitioning of the total system into a relevant part coupled to a dual bath. The latter consists of two parts: First, there is a set of strongly coupled harmonic modes, describing, for example, intramolecular degrees of freedom. They are treated on the basis of a reaction surface Hamiltonian approach. Second, there is a set of bath modes mimicking an unspecific environment modeled by means of a continuous spectral density. After deriving general equations expressing the canonical rate constant in terms of appropriate influence functionals, several approximations are introduced to provide an efficient numerical implementation. Results for an initial application to the H‐transfer in 6‐aminofulvene‐1‐aldimine are discussed. © 2011 Wiley Periodicals, Inc.
Improvement of estradiol esters monitoring in bovine hair by dansylation and liquid chromatography/tandem mass spectrometry analysis in multiple reaction monitoring and precursor ion scan modes
Authors: Bichon E. , Béasse A. , Prevost S. , Christien S. , Courant F. , Monteau F. , Le Bizec B.
Published: February 2012

RATIONALE

The control of forbidden anabolic practices in cattle in the European Union has become challenging since endogenous compounds such as estradiol derivatives can potentially be used as growth promoters. Due to the great difficulty in establishing a reference threshold value for endogenous steroids, the direct detection of steroid esters in hair is an efficient strategy for the detection of 'natural' steroid abuse in cattle.

METHODS

The present study aimed to develop and validate according to the current European standards a specific liquid chromatography/tandem mass spectrometry (LC/MS/MS) analytical strategy to monitor estrogen esters in bovine hair. The analysis was performed by positive ion electrospray ionisation (ESI+) after dansylation. Two acquisition modes were then assessed: single reaction monitoring and precursor ion scanning.

RESULTS

The results showed that the introduction of a dansylation step strongly improves the sensitivity of the detection of estradiol‐17‐esters by LC/(ESI+)‐MS/MS. The CCα values are in the range 1–10 ng g–1 after optimisation, except for estradiol decanoate for which the derivatisation is not efficient. In addition, this LC/MS/MS approach makes it possible to carry out a precursor ion scan to screen for the presence of these estradiol 17‐esters in hair samples.

CONCLUSIONS

Based on the specific product ions, i.e. m/z 255 in native conditions or m/z 171 after dansylation, this strategy has the advantage of detecting any (un)known estradiol ester and of giving access to the [M + H]+ ion of the suspected ester through only a single analysis. Copyright © 2012 John Wiley & Sons, Ltd.
Development of a liquid chromatographic method based on ultraviolet–visible and electrospray ionization mass spectrometric detection for the identification of nitrocatechols and related tracers in biomass burning atmospheric organic aerosol
Authors: Kitanovski Zoran , Grgić Irena , Yasmeen Farhat , Claeys Magda , Čusak Alen
Published: February 2012

RATIONALE

Studying the chemical composition of biomass burning aerosol (BBA) is very important in order to assess their impact on the climate and the biosphere. In the present study, we focus on the characterization of some newly recognized biomass burning aerosol tracers including methyl nitrocatechols, nitroguaiacols and 4‐nitrocatechol, but also on nitrophenols, methyl nitrophenols and nitrosalicylic acids, using liquid chromatography tandem mass spectrometry.

METHODS

For the purpose of their separation and detection in atmospheric aerosol, a new chromatographic method was initially developed based on reversed‐phase chromatography coupled with ultraviolet/visible (UV/Vis) detection. The method was afterwards transferred to a liquid chromatography/electrospray ionization linear ion trap mass spectrometry (LC/ESI‐LITMS) system in order to identify the targeted analytes in winter aerosol from the city of Maribor, Slovenia, using their chromatographic retention times and characteristic (−)ESI product ion (MS2) spectra.

RESULTS

The fragmentation patterns of analytes obtained with LITMS are presented. Additional nitro‐aromatic compounds (m/z 168 and 182) closely related to the targeted nitrocatechols and nitroguaiacols were detected in the aerosol. According to their MS2 spectra these compounds could be attributed to methyl homologues of methyl nitrocatechols and nitroguaiacols.

CONCLUSIONS

The proposed LC/MS method results in a better separation and specificity for the targeted analytes. Several nitro‐aromatic compounds were detected in urban BBA. The LC/MS peak intensity of the newly detected methyl nitrocatechols and nitroguaiacols is comparable to that of the methyl nitrocatechols, which also qualifies them as suitable molecular tracers for secondary biomass burning aerosol. Copyright © 2012 John Wiley & Sons, Ltd.
Protein crystal content analysis by mass spectrometry and preliminary X‐ray diffraction of a lectin from Canavalia grandiflora seeds with modulatory role in inflammation
Authors: Simões Rafael Conceição , Rocha Bruno Anderson Matias , Bezerra Maria Julia Barbosa , Barroso‐Neto Ito Liberato , Pereira‐Junior Francisco Nascimento , da Mata Moura Raniere , Nascimento Kyria Santiago do , Nagano Celso Shiniti , Delatorre Plinio , de Freitas Pires Alana , Assreuy Ana Maria Sampaio , Sampaio Alexandre Holanda , Cavada Benildo Sousa
Published: February 2012

RATIONALE

Lectins are a family of proteins capable of deciphering the glycan code. Several authors have published works about crystallization and mass spectrometry analyses of ConA‐like lectins. However, mass spectrometry has never been used to characterize lectin crystal content. In this study, Canavalia grandiflora lectin (ConGF), a ConA‐like lectin, was crystallized, part of its primary structure sequenced and the pro‐inflammatory activity evaluated. In addition, the crystal content was analyzed by mass spectrometry.

METHODS

ConGF was crystallized in the presence of X‐Man by hanging‐drop vapor diffusion at 293 K and the protein crystal content was analyzed by electrospray ionization in a SYNAPT HDMS mass spectrometer. Partial sequence was obtained by protein digestion with several proteolytic enzymes and the peptides sequenced by liquid chromatography/tandem mass spectrometry (LC/MS/MS). The pro‐inflammatory potential of ConGF was also evaluated in the model of rat paw edema.

RESULTS

The protein crystals consist of mature α chain and β and γ fragments measuring 25 612 ± 2 Da, 12 962 ± 2 Da and 12 667 ± 2 Da, respectively. The crystal belongs to the orthorhombic space group I222 (unit cell parameters: a = 67.70, b = 55.90, c = 107.46 Å), assuming a monomer in the asymmetric unit. The solvent content was calculated as 43.50% and the protein content as 2.5 µg. Furthermore, a significant part of the primary structure (65.8%) was determined by mass spectrometry.

CONCLUSIONS

As far as we know this is the first report of lectin crystal content characterized by mass spectrometry. Like other ConA‐like lectins, GonGF induced paw edema however differing in potency and duration. The observed pro‐inflammatory activity suggests that ConGF might be a useful tool in the study of inflammation processes and structure/function relationships. Copyright © 2012 John Wiley & Sons, Ltd.
The scaling window for a random graph with a given degree sequence
Authors: Hatami Hamed , Molloy Michael
Published: February 2012

We consider a random graph on a given degree sequence D, satisfying certain conditions. Molloy and Reed defined a parameter Q = Q(D) and proved that Q = 0 is the threshold for the random graph to have a giant component. We introduce a new parameter R = R(
\documentclass{article}\usepackage{mathrsfs, amsmath, amssymb}\pagestyle{empty}\begin{document}\begin{align*}\mathcal {D}\end{align*} \end{document}) and prove that if |Q| = O(n‐1/3R2/3) then, with high probability, the size of the largest component of the random graph will be of order Θ(n2/3R‐1/3). If |Q| is asymptotically larger than n‐1/3R2/3 then the size of the largest component is asymptotically smaller or larger than n2/3R‐1/3. Thus, we establish that the scaling window is |Q| = O(n‐1/3R2/3). © 2012 Wiley Periodicals, Inc. Random Struct. Alg., 2012