bluuebunny/crossref_metadata_2025 huggingface dataset:
Multidisciplinary characterisation of sedimentary processes in a recent maar lake (Lake Pavin, French Massif Central) and implication for natural hazards
Authors: Chapron E. , Albéric P. , Jézéquel D. , Versteeg W. , Bourdier J.-L. , Sitbon J.
Published: September 2010

Abstract. Sedimentation processes occurring in the most recent maar lake of the French Massif Central (Lake Pavin) are documented for the first time based on high resolution seismic reflection and multibeam bathymetric surveys and by piston coring and radiocarbon dating on a sediment depocentre developed on a narrow sub aquatic plateau. This new data set confirms the mid Holocene age of maar lake Pavin formation at 6970±60 yrs cal BP and highlights a wide range of gravity reworking phenomena affecting the basin. In particular, a slump deposit dated between AD 580–640 remoulded both mid-Holocene lacustrine sediments, terrestrial plant debris and some volcanic material from the northern crater inner walls. Between AD 1200 and AD 1300, a large slide scar mapped at 50 m depth also affected the southern edge of the sub aquatic plateau, suggesting that these gas-rich biogenic sediments (laminated diatomite) are poorly stable. Although several triggering mechanisms can be proposed for these prehistoric sub-aquatic mass wasting deposits in Lake Pavin, we argue that such large remobilisation of gas-rich sediments may affect the gas stability in deep waters of meromictic maar lakes. This study highlights the need to further document mass wasting processes in maar lakes and their impacts on the generation of waves, favouring the development of dangerous (and potentially deadly) limnic eruptions.
Shallow landslide prediction in the Serra do Mar, São Paulo, Brazil
Authors: Vieira B. C. , Fernandes N. F. , Filho O. A.
Published: September 2010

Abstract. Various methods are currently used in order to predict shallow landslides within the catchment scale. Among them, physically based models present advantages associated with the physical description of processes by means of mathematical equations. The main objective of this research is the prediction of shallow landslides using TRIGRS model, in a pilot catchment located at Serra do Mar mountain range, São Paulo State, southeastern Brazil. Susceptibility scenarios have been simulated taking into account different mechanical and hydrological values. These scenarios were analysed based on a landslide scars map from the January 1985 event, upon which two indexes were applied: Scars Concentration (SC – ratio between the number of cells with scars, in each class, and the total number of cells with scars within the catchment) and Landslide Potential (LP – ratio between the number of cells with scars, in each class, and the total number of cells in that same class). The results showed a significant agreement between the simulated scenarios and the scar's map. In unstable areas (SF≤1), the SC values exceeded 50% in all scenarios. Based on the results, the use of this model should be considered an important tool for shallow landslide prediction, especially in areas where mechanical and hydrological properties of the materials are not well known.
Reanalysis of multi-temporal aerial images of Storglaciären, Sweden (1959–99) – Part 1: Determination of length, area, and volume changes
Authors: Koblet T. , Gärtner-Roer I. , Zemp M. , Jansson P. , Thee P. , Haeberli W. , Holmlund P.
Published: September 2010

Abstract. Storglaciären, located in the Kebnekaise massif in northern Sweden, has a long history of glaciological research. Early photo documentations date back to the late 19th century. Measurements of front position variations and distributed mass balance have been carried out since 1910 and 1945/46, respectively. In addition to these in-situ measurements, aerial photographs have been taken at decadal intervals since the beginning of the mass balance monitoring program and were used to produce topographic glacier maps. Inaccuracies in the maps were a challenge to early attempts to derive glacier volume changes and resulted in major differences when compared to the direct glaciological mass balances. In this study, we reanalyzed dia-positives of the original aerial photographs of 1959, -69, -80, -90 and -99 based on consistent photogrammetric processing. From the resulting digital elevation models and orthophotos, changes in length, area, and volume of Storglaciären were computed between the survey years, including an assessment of related errors. Between 1959 and 1999, Storglaciären lost an ice volume of 19×106 m3, which corresponds to a cumulative ice thickness loss of 5.69 m and a mean annual loss of 0.14 m. This ice loss resulted largely from a strong volume loss during the period 1959–80 and was partly compensated during the period 1980–99. As a consequence, the glacier shows a strong retreat in the 1960s, a slowing in the 1970s, and pseudo-stationary conditions in the 1980s and 1990s.
Reanalysis of multi-temporal aerial images of Storglaciären, Sweden (1959–99) – Part 2: Comparison of glaciological and volumetric mass balances
Authors: Zemp M. , Jansson P. , Holmlund P. , Gärtner-Roer I. , Koblet T. , Thee P. , Haeberli W.
Published: September 2010

Abstract. Seasonal glaciological mass balances have been measured on Storglaciären without interruption since 1945/46. In addition, aerial surveys have been carried out on a decadal basis since the beginning of the observation program. Early studies had used the resulting aerial photographs to produce topographic glacier maps with which the in-situ observations could be verified. However, these maps as well as the derived volume changes are subject to errors which resulted in major differences between the derived volumetric and the glaciological mass balance. As a consequence, the original photographs were re-processed using uniform photogrammetric methods, which resulted in new volumetric mass balances for 1959–69, 1969–80, 1980–90, and 1990–99. We compared these new volumetric mass balances with mass balances obtained by standard glaciological methods including an uncertainty assessment considering all related previous studies. The absolute differences between volumetric and the glaciological mass balances are 0.8 m w.e. for the period of 1959–69 and 0.3 m w.e. or less for the other survey periods. These deviations are slightly reduced when considering corrections for systematic uncertainties due to differences in survey dates, reference areas, and internal ablation, whereas internal accumulation systematically increases the mismatch. However, the mean annual differences between glaciological and volumetric mass balance are less than the uncertainty of the in-situ stake reading and stochastic error bars of both data series overlap. Hence, no adjustment of the glaciological data series to the volumetric one is required.
Synthesis of a 2‐Selenothymidine Phosphoramidite and Its Incorporation into Oligodeoxyribonucleotides
Authors: Zhang Wen , Huang Zhen
Published: September 2010

The detailed synthetic protocol for a 2‐selenothymidine phosphoramidite and its use in preparing Se‐derivatized oligonucleotides are described here. The Se‐modified phosphoramidite synthesis was achieved by activating a 2‐thiothymidine derivative, followed by introduction of selenium functionality. The coupling reaction yield of the 2‐selenothymidine phosphoramidite during solid‐phase synthesis is high (>95%), and the oligonucleotides containing the 2‐selenothymidine derivatization are stable. Curr. Protoc. Nucleic Acid Chem. 42:1.23.1‐1.23.13. © 2010 by John Wiley & Sons, Inc.
Hyperuricemia and incident hypertension: A systematic review and meta‐analysis
Authors: Grayson Peter C. , Kim Seo Young , LaValley Michael , Choi Hyon K.
Published: September 2010

Objective

A novel rodent model and a recent randomized trial of hyperuricemic adolescents with hypertension suggest a pathogenetic role of uric acid in hypertension, but it remains unknown whether these findings would be applicable to adult populations where the larger disease burden exists. We conducted a systematic review and meta‐analysis to determine if hyperuricemia was associated with incident hypertension, particularly in various demographic subgroups.

Methods

We searched major electronic databases using medical subject headings and keywords without language restrictions (through April 2010). We included prospective cohort studies with data on incident hypertension related to serum uric acid levels. Data abstraction was conducted in duplicate. We analyzed age, sex, and race subgroups.

Results

A total of 18 prospective cohort studies representing data from 55,607 participants were included. Hyperuricemia was associated with an increased risk for incident hypertension (adjusted risk ratio [RR] 1.41, 95% confidence interval [95% CI] 1.23–1.58). For a 1 mg/dl increase in uric acid level, the pooled RR for incident hypertension after adjusting for potential confounding was 1.13 (95% CI 1.06–1.20). These effects were significantly larger in younger study populations (P = 0.02) and tended to be larger in women (P = 0.059). Two studies suggested that the effect may also be larger among African American individuals. Furthermore, later publication year and US‐based studies were significantly associated with a lower effect estimate (P values <0.02).

Conclusion

Hyperuricemia is associated with an increased risk for incident hypertension, independent of traditional hypertension risk factors. This risk appears more pronounced in younger individuals and women.
Responsiveness of the ABILHAND questionnaire in measuring changes in rheumatoid arthritis patients
Authors: Batcho Charles Sèbiyo , Durez Patrick , Thonnard Jean‐Louis
Published: September 2010

Objective

ABILHAND is a Rasch‐built questionnaire that measures manual ability in rheumatoid arthritis (RA) patients. This study aimed to examine the test–retest reliability and the responsiveness of ABILHAND in RA patients.

Methods

Eighty‐eight patients underwent 3 evaluations: the first evaluation was at baseline (time 1), the second was 2 weeks later (time 2), and the third was 1 year later (time 3). Disease activity was assessed using the Disease Activity Score in 28 joints using the C‐reactive protein level (DAS28‐CRP). Patients rated the intensity of their RA‐related pain using a 100‐mm visual analog scale for pain and completed questionnaires based on their activity limitations (ABILHAND and the Health Assessment Questionnaire) and quality of life.

Results

The responsiveness analyses were conducted by using global, group, and individual approaches. The global approach showed significant differences between the time 1 and time 3 scores of the DAS28‐CRP (P = 0.04) and ABILHAND (P = 0.04). Based on the changes in disease activity scores and the European League Against Rheumatism response criteria, the sample was divided into 3 groups: deteriorated, stable, and improved. The mean ± SD changes in manual ability were higher in the deteriorated (−1.23 ± 1.53 logit) and in the improved (1.22 ± 2.06 logits) groups than in the stable group (0.48 ± 1.09 logit). The effect size and standardized response mean confirmed that observation. The minimal clinically important difference was assessed in each group of patients.

Conclusion

The ABILHAND questionnaire exhibited responsiveness in detecting slight changes in RA patients. Therefore, the ABILHAND tool can be used to evaluate the functional status of RA patients in clinical trials and settings.
A Three‐Dimensional Nanostructured Array of Protein Nanoparticles
Authors: Seo Hyuk‐Seong , Kim Seong‐Eun , Park Jin‐Seung , Lee Jong‐Hwan , Yang Ki‐Yeon , Lee Heon , Lee Kyung Eun , Han Sung‐Sik , Lee Jeewon
Published: September 2010

Here a novel technique is reported to construct a three‐dimensional (3D) array of well‐defined and controllable multilayered nanostructures of proteins that is based on alternate layer‐by‐layer assembly of bacterial protein nanoparticles and DNA on a patterned array of gold dots. This is the first report on protein‐based multilayer stacking, which has the following significant advantages over conventional multilayer assemblies: 1) avoiding hazardous chemicals, the multilayer assembly is implemented in aqueous solution under mild temperature and pH conditions over a relatively short period; 2) direct multilayer growth from designated position is possible by controlling the aspect ratio; 3) multicomponent stacking can be easily performed through alternate stacking of different building blocks (in this case protein nanoparticles); and 4) a wide variety of 3D arrays can be constructed using various functionalized protein nanoparticles that are easily prepared through a simple genetic engineering approach. In this study, as a proof of concept, the developed 3D and patterned arrays of protein nanoparticle multilayers are successfully applied to the multiplexed bioassays of breast and colorectal cancer markers.
Control of the Properties of Micrometer‐Sized Actuators from Liquid Crystalline Elastomers Prepared in a Microfluidic Setup
Authors: Ohm Christian , Fleischmann Eva‐Kristina , Kraus Isabelle , Serra Christophe , Zentel Rudolf
Published: September 2010

In this article new results on the preparation of monodisperse particles from a liquid crystalline elastomer in a microfluidic setup are presnted. For this, droplets from a liquid crystalline monomer are prepared in a microfluidic device and polymerized while they are flowing inside a microtube. The parti­cles obtained by this method possess an internal orientation, which gives them actuating properties. When they are heated into the isotropic phase of the liquid crystalline material they show a reversible change in shape whereby they change their length in one direction by almost 100%. It is shown how the variation of experimental parameters during their synthesis impacts the properties of these micro‐actuators. Influence over their primal shape, the strength of their shape changing properties, their size, and their mechanical properties is demontrated. From the systematic variation of experimental parameters a deep understanding of the complex processes taking place in a flowing droplet of a liquid crystalline material is obtainted. Additionally NMR analysis and swelling experiments on these actuating materials are provided.
Room‐Temperature Ferromagnetic Silver Vanadium Oxide (Ag1.2V3O8): A Magnetic Semiconductor Nanoring Structure
Authors: Wu Changzheng , Zhu Haiou , Dai Jun , Yan Wensheng , Yang Jinlong , Tian Yangchao , Wei Shiqiang , Xie Yi
Published: September 2010

Magnetic nanoring structures are attractive for spintronic devices due to their unique attributes of well‐defined and reproducible magnetic states originating from their characteristic geometry. Almost all previous magnetic nanorings have been exclusively limited to traditional ferromagnetic materials, and a magnetic semiconductor (MSC) nanoring structure has been reported rarely during the past decades. Here, it is demonstrated that room‐temperature ferromagnetic Ag1.2V3O8 nanobelts and nanorings may be achieved by controlled oxidation of the V4+ precursors in an Ag+‐containing aqueous solution. The polarization‐induced self‐coiling of in situ formed Ag1.2V3O8 nanobelts is responsible for the formation of the perfectly circular nanoring geometry. The NEXAFS spectra and the density functional calculations clearly reveal that the electron transfer originates from the hybridization of the doped Ag+ and V4+ atoms, causing ordering of the magnetic moments that give rise to the intrinsic ferromagnetism of the Ag1.2V3O8 structure.
Biocompatible Bright YVO4:Eu Nanoparticles as Versatile Optical Bioprobes
Authors: Shen Jie , Sun Ling‐Dong , Zhu Jia‐Dan , Wei Liu‐He , Sun Hong‐Fang , Yan Chun‐Hua
Published: September 2010

Lanthanide nanoparticles (NPs), characterized by their large Stokes’ shifts, narrow emission bands and high photochemical stability, are promising candidates for optical probes in biological research. As a typical red emission material, Eu3+‐doped YVO4 is investigated in pursuit of an integral methodology for Ln‐based bioprobes. Assisted with phosphino‐polyacrylic acid, YVO4:Eu NPs with a luminescent quantum yield of ca. 54% are synthesized via a one‐pot hydrothermal reaction. The obtained NPs exhibit good water/buffer stability and feasible biomodification benefiting from the surface carboxylic acid groups. However, having an inorganic core of ca. 20 nm, these NPs do not affect the conformation of surface conjugated proteins (bovine serum albumin), as confirmed with the circular dichroism spectrum. A specific recognition protocol is demonstrated by biotinated YVO4:Eu NPs in quantitative fluoroimmunoassay and microchip assay. Furthermore, the biocompatibility of the Ln NPs, which is an important aspect towards biological application, is demonstrated with the MTT [3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide] assay. Cell imaging studies conducted with spectral mapping technique and confocal fluorescent microscopy demonstrate the YVO4:Eu NPs to be a type of competitive luminescent probes for in vitro applications.
Insoluble Perfluoroalkylated Polymers: New Solid Supports for Supported Fluorous Phase Catalysis
Authors: Audic Nicolas , Dyer Philip W. , Hope Eric G. , Stuart Alison M. , Suhard Samuel
Published: September 2010

New perfluoroalkylated polystyrene resins have been prepared by the suspension polymerisation of 4‐(perfluoro‐n‐octyl)styrene. The evaluation of these highly fluorinated insoluble materials as catalyst supports for rhodium‐catalysed hydrogenation of styrene and palladium‐mediated Suzuki–Miyaura carbon‐carbon bond forming reactions with 4‐bromoacetophenone and 4‐bromoanisole revealed improvements in the recycling of the perfluoroalkylated catalysts as compared to that achieved using fluorous reverse‐phase silica gel.
Efficient Platinum(II) Catalyzed Hydroformylation Reaction in Water: Unusual Product Distribution in Micellar Media
Authors: Gottardo Marina , Scarso Alessandro , Paganelli Stefano , Strukul Giorgio
Published: September 2010

The hydroformylation of a variety of terminal and internal alkenes is efficiently performed by cationic platinum triflate complexes of the type [P2Pt(H2O)2](OTf)2 under mild conditions in an aqueous micellar medium. The use of surfactants is essential to ensure dissolution of the catalyst and substrate in water with catalysts being positioned on the anionic surface of the micelles. Aldehydes are obtained with linear to branched ratios up to >99:1. With styrene derivatives also the corresponding benzaldehydes are formed. The catalyst can be separated by extraction of the organic products with hexane and recycled for at least four times with only a modest loss of activity and no effect on selectivity.
Enders’ SAMP‐Hydrazone as Traceless Auxiliary in the Asymmetric 1,4‐Addition of Cuprates to Enones
Authors: Sammet Karsten , Gastl Christoph , Baro Angelika , Laschat Sabine , Fischer Peter , Fettig Ina
Published: September 2010

Conjugate additions of Gilman cyanocuprates to (S)‐N‐amino‐2‐(methoxymethyl)pyrrolidine (SAMP)‐hydrazones 4, 5 derived from cyclic and acyclic α,β‐unsaturated ketones were investigated. A protocol utilizing copper(II) sulfate/ammonium chloride was evolved, which allowed cleavage of SAMP (S)‐1 under the hydrolysis and work‐up conditions, followed by recovery of the auxiliary with ethylenediaminetetraacetic acid (EDTA). The enantioselectivity of cuprate additions was dominated for cyclic SAMP‐hydrazones 4 by the cuprate alkyl substituent and the ring size, in the case of acyclic arylidene SAMP‐hydrazones 5, however, by the nature of the aryl substituent. Electron‐donating substituents gave poor enantiomeric excesses, whereas electron‐withdrawing groups provided excellent ee values of 98–99%. The configuration of the new stereocenter was determined to be (R). Moreover, a reaction sequence was developed which integrates a tandem 1,4‐addition/methylation and traceless hydrolytic cleavage of the auxiliary (S)‐1 in a one‐pot reaction, resulting in enantiomerically pure methyl ketones 11–13, each of them with>99% ee.
Redox‐Active Catalyst Based on Poly(Anilinesulfonic Acid)‐ Supported Gold Nanoparticles for Aerobic Alcohol Oxidation in Water
Authors: Saio Daisuke , Amaya Toru , Hirao Toshikazu
Published: September 2010

The hybrid consisting of gold nanoparticles and poly(2‐methoxyaniline‐5‐sulfonic acid), which works as a redox mediator for transferring protons and electrons, catalyzed the oxidation reaction of various alcohols in water under molecular oxygen.
Reactive extrusion processing of polypropylene/TiO2 nanocomposites by in situ synthesis of the nanofillers: Experiments and modeling
Authors: Bahloul Walid , Oddes Olivier , Bounor‐Legaré Véronique , Mélis Flavien , Cassagnau Philippe , Vergnes Bruno
Published: September 2010

The effects of twin‐screw extrusion processing conditions upon the formation of polypropylene/titanium dioxide (PP/TiO2) nanocomposites are investigated. To prepare PP/TiO2 nanocomposites by limiting the problem of filler dispersion at the nanoscale, an original method was developed based on the creation of TiO2 through hydrolysis–condensation reactions (sol–gel method) of titanium n‐butoxide precursor during PP extrusion. The feed rate, the screw speed, and the amount of inorganic precursor were varied independently. The conversion rate of precursor as a function of process parameters was quantified by gas chromatography and mass spectroscopy combined techniques through the assessment of the alcohol formed. The effects of processing conditions on the development of the sol–gel reaction have also been investigated by using numerical simulations. The comparison between experimental and theoretical results shows that this simulation approach is relevant to predict the conversion of the inorganic precursor to TiO2 through hydrolysis–condensation reactions in molten PP. © 2011 American Institute of Chemical Engineers AIChE J, 2011
A 4D imaging tool for Lagrangian particle tracking in stirred tanks
Authors: Cheng Y. , Diez F. J.
Published: September 2010

A time‐resolved volumetric 3D particle tracking tool is presented for mixing in stirred tanks studies and its capabilities are explored in a low Reynolds number custom‐made stirred tank. The technique provides a Lagrangian description of particles in the flow resolving their 3D trajectories, velocities, and acceleration. The optimization of the system allowed, for the first time, tracking ∼400 particles at a time in an imaged volume (60 mm × 60 mm × 50 mm) in the stirred tank. The system was validated in a 1‐D piston‐driven flow and by comparing the measurements with a 2D‐particle image velocimetry system in a stirred tank. Results show the advantages of this technique to understand particle dynamics. Sample measurements illustrated that small changes in the stirrer configuration produced an unexpected variety of particle trajectories which were classified according to their path shape and location. Particle velocities and Lagrangian accelerations provided new insights into their mixing process. © 2010 American Institute of Chemical Engineers AIChE J, 2011
Mutational spectrum in congenital dyserythropoietic anemia type II: Identification of 19 novel variants in SEC23B gene
Authors: Russo Roberta , Esposito Maria Rosaria , Asci Roberta , Gambale Antonella , Perrotta Silverio , Ramenghi Ugo , Forni Gian Luca , Uygun Vedat , Delaunay Jean , Iolascon Achille
Published: September 2010

SEC23B gene encodes an essential component of the coat protein complex II (COPII)‐coated vesicles. Mutations in this gene cause the vast majority the congenital dyserythropoietic anemia Type II (CDA II), a rare disorder resulting from impaired erythropoiesis. Here, we investigated 28 CDA II patients from 21 unrelated families enrolled in the CDA II International Registry. Overall, we found 19 novel variants [c.2270 A>C p.H757P; c.2149−2 A>G; c.1109+1 G>A; c.387(delG) p.L129LfsX26; c.1858 A>G p.M620V; c.1832 G>C p.R611P; c.1735 T>A p.Y579N; c.1254 T>G p.I418M; c.1015 C>T p.R339X; c.1603 C>T p.R535X; c.1654 C>T p.L552F; c.1307 C>T p.S436L; c.279+3 A>G; c. 2150(delC) p.A717VfsX7; c.1733 T>C p.L578P; c.1109+5 G>A; c.221+31 A>G; c.367 C>T p.R123X; c.1857_1859delCAT; p.I619del] in the homozygous or the compound heterozygous state. Homozygosity or compound heterozygosity for two nonsense mutations was never found. In four cases the sequencing analysis has failed to find two mutations. To discuss the putative functional consequences of missense mutations, computational analysis and sequence alignment were performed. Our data underscore the high allelic heterogeneity of CDA II, as the most of SEC23B variations are inherited as private mutations. In this mutation update, we also provided a tool to improve and facilitate the molecular diagnosis of CDA II by defining the frequency of mutations in each exon. Am. J. Hematol., 2010. © 2010 Wiley‐Liss, Inc.
Nickel and copper removal study from aqueous solution using new cationic poly[acrylamide/N,N‐DAMB/N,N‐DAPB] super absorbent hydrogel
Authors: Patel Ankit M. , Patel Ranjan G. , Patel Manish P.
Published: September 2010

A new cationic poly[acrylamide/N,N‐diallyl morpholinium bromide/N,N‐diallyl piperidinium bromide] super absorbent hydrogels (H1–H7) were prepared via microwave irradiated free radical cyclopolymerization using different composition. By the swelling study, hydrogel H1 is found to bear good swelling properties amongst all prepared hydrogels. The hydrogel H1 has been characterized by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscope (SEM), and TGA analysis. A batch system was applied to study the adsorption of Ni(II) and Cu(II) from aqueous solutions by hydrogel H1. The effect of treatment time, pH of the medium, amount of adsorbent doses, and initial feed concentration of metal ion on adsorption of Ni(II) and Cu(II) from their solution were also investigated. Adsorption of Ni(II) and Cu(II) increases with the increase in treatment time, adsorbent doses, and initial feed concentration and decreases with the increase in pH of the medium. The desorption of metal ions were carried out using 1N HCl and 0.5N H2SO4. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Comparative studies of acetylcholinesterase purified from three field populations of Liposcelis entomophila (enderlein) (psocoptera: liposcelididae)
Authors: Xiao Li‐Sha , Dou Wei , Li Yin , Wang Jin‐Jun
Published: September 2010

Acetylcholinesterace (AChE) is known to be the major target for organophophate and carbamate insecticides and biomolecular changes to AChE have been demonstrated to be an important mechanism for insecticide resistance in many insect species. In this study, AChE from three field populations of Liposcelis entomophila (Enderlein) (Psocoptera: Liposcelididae) was purified by affinity chromatography and subsequently characterized by its Michaelis‐Menten kinetics to determine if detectable changes to AChE have occurred. Bioassays revealed that the potential resistance threat of psocids in Sichuan Province (GH) was greater than either Hubei Province (WH) or Chongqing Municipality (BB). Compared to the other two populations, the WH population possessed the highest specific activity of purified AChE. Kinetic analyses indicated that the purified AChE from GH population expressed a significantly lower affinity to the substrate and a higher catalytic activity toward acetylthiocholine iodide (ATChI) (i.e., higher Km and Vmax values) than BB and WH populations. In vitro studies of AChE suggest that five inhibitors (aldicarb, eserine, BW284C51, omethoate, and propoxur) all possess strong inhibitory effects with eserine having the strongest inhibitory effect against purified AChE. According to bimolecular rate constants (ki), the purified AChE from GH population was least sensitive to all inhibitors except for omethoate. The differences in AChE among the three populations may be partially attributed to the differences in pesticide application and control practices for psocids among the three locations. © 2010 Wiley Periodicals, Inc.
Characterization of the Mamestra configurata (Lepidoptera: Noctuidae) larval midgut protease complement and adaptation to feeding on artificial diet, Brassica species, and protease inhibitor
Authors: Erlandson Martin A. , Hegedus Dwayne D. , Baldwin Douglas , Noakes Amy , Toprak Umut
Published: September 2010

The midgut protease profiles from 5th instar Mamestra configurata larvae fed various diets (standard artificial diet, low protein diet, low protein diet with soybean trypsin inhibitor [SBTI], or Brassica napus) were characterized by one‐dimensional enzymography in gelatin gels. The gut protease profile of larvae fed B. napus possessed protease activities of molecular masses of approximately 33 and 55 kDa, which were not present in the guts of larvae fed artificial diet. Similarly, larvae fed artificial diet had protease activities of molecular masses of approximately 21, 30, and 100 kDa that were absent in larvae fed B. napus. Protease profiles changed within 12 to 24 h after switching larvae from artificial diet to plant diet and vice versa. The gut protease profiles from larvae fed various other brassicaceous species and lines having different secondary metabolite profiles did not differ despite significant differences in larval growth rates on the different host plants. Genes encoding putative digestive proteolytic enzymes, including four carboxypeptidases, five aminopeptidases, and 48 serine proteases, were identified in cDNA libraries from 4th instar M. configurata midgut tissue. Many of the protease‐encoding genes were expressed at similar levels on all diets; however, three chymoptrypsin‐like genes (McSP23, McSP27, and McSP37) were expressed at much higher levels on standard artificial diet and diet containing SBTI as was the trypsin‐like gene McSP34. The expression of the trypsin‐like gene McSP50 was highest on B. napus. The adaptation of M. configurata digestive biochemistry to different diets is discussed in the context of the flexibility of polyphagous insects to changing diet sources. Published 2010 Wiley Periodicals, Inc.
Putative‐farnesoic acid O‐methyltransferase (FAMeT) in medfly reproduction
Authors: Vannini Laura , Ciolfi Silvia , Dallai Romano , Frati Francesco , Hoffmann Klaus H. , Meyering‐Vos Martina
Published: September 2010

A gene potentially involved in juvenile hormone (JH) biosynthesis was previously identified in Ceratitis capitata as the putative‐farnesoic acid O‐methyltransferase (FAMeT). Since JH is involved in insect reproduction, we silenced the putative‐FAMeT expression by RNA interference in Ceratitis capitata to evaluate its implication in egg production. FAMeT gene expression was knocked down in females and males after eclosion and in 1‐ and 2‐day‐old females. Treated specimens were left to mate with each other or with untreated partners to evaluate the extent of each sex influencing egg production. Gene silencing was investigated by Real‐Time PCR. Results unambiguously showed that FAMeT has a measurable role on the fertility of both medfly sexes. © 2010 Wiley Periodicals, Inc.
Imidazolidin‐2‐one prostaglandin analogues
Authors: Barraclough Paul , Jackson William P. , Harris John
Published: September 2010

The 5‐desoxy analogue of BW245C, imidazolidin‐2‐one 3, has been synthesized by reduction of the N‐benzyl hydantoin derivative 6. Compound 3 was found to be approximately equipment with BW245C as an inhibitor of platelet aggregation and this result indicates that the 5‐keto group of BW245C is not essential for platelet inhibitory activity.
Conformation of cis‐4‐Hydroxy‐praziquantel and its crystal and molecular structure
Authors: Karolak‐Wojciechowska Janina , Kwiatkowski Witold , Kiec‐Kononowicz Katarzyna , Blaschke Gottfried
Published: September 2010

The crystal structure of racemic cis‐4‐OH‐PZQ ‐ the main metabolite of the anthelmintic drug Praziquantel ‐ has been determined by X‐ray analysis and refined to R = 0.064. In the unit cell there are two independent molecules, but with a similar conformation. The molecules of the same enantiomer (joined by H‐bonds) form in the crystal a column along a‐axis direction. Molecular mechanics calculations indicate that the conformation in the solid state does not correspond to the energy minimum and there are two lower energy conformations. Thus, in solutions these two conformers can most probably exist. Their concentration in solutions depends on the solvent polarity and the value of the dipole moment for the respective form of the molecule.
Synthesis of some basic 3‐(1‐acylaminobenzyl)‐2H‐1‐benzopyran‐2‐ones
Authors: Bojilova Anka , Ivanova Diana
Published: September 2010

The reaction of 3‐(1‐propanoyloxybenzyl)‐2H‐1‐benzopyran‐2‐one (2) with the nitriles of 4‐dimethylaminobenzoic, 4‐diethylaminobenzoic, nicotinic, isonicotinic, and 3‐dimethylaminopropionic acid in conc. H2SO4 yields the amides 3a‐e. 3a‐d were converted into hydrochlorides.
Untersuchungen an 1,4‐Naphthochinonen, 21. Mitt.: 2‐(3,5‐Di‐Tert‐Butyl‐4‐Hydroxyphenyl)‐1,4‐Naphthochinone Als 5‐Lipoxygenasehemmer
Authors: Wurm Gotthard
Published: September 2010

Als potentielle 5‐Lipoxygenase‐Inhibitoren wird eine Reihe von 3,5‐Di‐tert‐butyl‐4‐hydroxyphenyl‐1,4‐naphthochinonderivaten ‐ speziell 10 und 11 ‐ synthetisiert. Die Schlüsselverbindungen sind 3 und 9a‐b. die durch 1,4‐Addition von 2,6‐Di‐tert‐butylphenol (2) an 2‐Brom/Chlor‐ (1a‐b) und 2,3‐Dibrom/Dichlor‐1,4‐naphthochinon (8a‐b) gebildet werden. Das 3‐Methylderivat 5 entsteht durch radikalische Methylierung von 3. 9a‐b sind die Bausteine für die Synthese der erwarteten Lipoxygenase‐Hemmer 10 und 11. Während 10 im Verlauf eines Additions‐Elimination‐Prozesses in alkalischem Methanol bei Raumtemp. gebildet wird, entsteht 11 durch Hydrolyse von 10 in einer Eintopfreaktion durch Erhitzen von 9a‐b in alkalisch wäßrigem Methanol. 11 wird schlagartig durch CAN‐Oxidation in das Chinonmethid‐Analogon 12 überführt. 9a‐b sind außerdem geeignete Komponenten für die Reaktion mit Aminen, wobei Derivate wie 13 in mäßiger Ausbeute entstehen.
Synthesis of 5′‐N‐(α‐Amino‐β‐mercaptoacyl)amino‐5′‐deoxynucleosides as potential antiviral compounds
Authors: Herranz Rosario , Castro‐Pichel Julia , García‐López M. Teresa , Pérez Concepción , Balzarini Jan , De Clercq Erik
Published: September 2010

5′‐N‐(α‐Amino‐β‐mercaptoacyl)amino‐5′‐deoxynucleosides have been synthesized by coupling of N‐formylthiazolidines derived from D‐ and L‐penicillamine, and D‐ and L‐cysteine to 5′‐amino‐5′‐deoxynucleosides using the DCC/HOSu method, followed by deprotection in N HCL in MeOH under argon. Although these compounds were designed as potential anti‐HIV‐1 agents, none of them showed anti‐HIV‐1 activity in MT‐4 cells or antiviral effect against some other viruses, at concentrations below the cytotoxicity threshold.
Zur Pharmakokinetik Von Lipidsenkern, 8. Mitt.: Eindeutige Charakterisierung Des Ciprofibrat‐o‐β‐D‐Giukuronids
Authors: Oelschläger Herbert , Kohl Christopher , Armstrong Daniel W. , Rothley Dietrich
Published: September 2010

Der racemische Lipidsenker Ciprofibrat (1) wird nach oraler Einmalgabe überwiegend (> 90%) als Glukuronid renal und zu einem geringen Teil auch biliär ausgeschieden. Dieses aus dem Ham extrahierte Konjugat wird durch Methylieren der Carboxygruppe und Acetylieren der drei OH‐Gruppen der Glukuronsäurekomponente in das hydrophobe Methyl‐(2,3,4‐Tri‐O‐acetyl‐β‐D‐glucopyran)‐uronat übergeführt, das mil Hilfe der HPLC unter Einsatz der leicht herstellbaren Referenzsubstanz eindeutig identifiziert werden kann. Infolge der Chiralität von 1 resultieren das Glukuronid und sein hydrophobes Derivat vom Schmelzbereich 67‐78°C als Diastereomerengemisch. Das letztere konnte analytisch an einer Cyclobond I‐Säule in die beiden Diastereomeren getrennt werden.
Synthesen neuer überbrückter heterocyclen durch 1,3‐dipolare cycloadditionen
Authors: Neidlein Richard , Lu Yinrong , Kramer Walter
Published: September 2010

Syntheses of New Bridged Heterocycles by 1,3‐Dipolar Cycloaddition

Cycloaddition of bridged Quinonehydrazones 1, 4, 5 with mesoionic reagents are studied; the p‐nitrophenylhydrazone 1 reacts with 3‐phenylsydnone (2) under elimination of CO2 and dehydrogenation yielding the linearly annulated heterocyclic cycloadduct 3; as opposed to this reaction cycloaddition of phenylsydnone 2 with N‐methyl‐(4)‐ and N‐benzyl‐(5)‐hydrazone derivatives produces the methanobridged heterocycles 6 and 7, respectively.
Imidazo[4,5‐b]pyridine derivatives of potential tuberculostatic activity, II: Synthesis and bioactivity of designed and some other 2‐cyanomethylimidazo[4,5‐b]pyridine derivatives
Authors: Bukowski Ludwik , Kaliszan Roman
Published: September 2010

Based on the analysis of Quantitative Structure ‐ Activity Relationships (QSAR) three representatives of imidazo[4,5‐b]pyridine derivatives of predicted high antibacterial activity against Mycobacterium tuberculosis were synthetized and tested bacteriologically. Excellent agreement of the predicted and experimentally observed bioactivity was noted. Additional new derivatives of 4‐methyl‐4H‐2‐cyanomethylimidazo[4,5‐b]pyridine (7) and 2‐(α‐methylcyanomethyl)imidazo[4,5‐b]pyridine (22) were also synthesized and some of them were tested for tuberculostatic activity. The compounds synthesized according to a standard “trial and error” approach appeared generally inactive.
Synthese, Biotransformation und Pharmakodynamik eines neuen Theophyllinderivats
Authors: Oelschläger Herbert , Harsche Christian , Engel Jürgen
Published: September 2010

Synthesis, Biotransformation, and Pharmacodynamics of a New Theophylline Derivative

7‐[(RS)2‐((RS)‐1‐Methyl‐2‐phenyl‐ethylamino)propyl]‐theophylline (3) was not described until now. This fenetylline analogue is available by reaction of 7 with an excess of 2 at 150°C. If 2 reacts with 4, an E2‐elimination overwhelms SN‐nucleophilic displacement yielding compound 5. In vivo studies with male White‐Wistar rats, comparing biotransformation of 3 and 1, demonstrate, that the amount of 2 is decreased from 4.7% of (RS)‐2 to 1%, probably due to steric hindrance of the attacking monooxygenases by the methyl group at C‐11 of 3. Pharmacodynamic studies of 3, tested with mice, gave similar results to those obtained with 1.
An efficient and practical EPC synthesis of β‐amino acids from L‐asparagine
Authors: Gmeiner Peter
Published: September 2010

The synthesis of enantiomerically pure β‐arnino acids (1a‐c) via an O‐activated equivalent of β‐homoserine is discussed. The chiral synthon 2 was planned to be represented by (S)‐3‐N,N‐dibenzylamino‐4‐mesyloxybutanoic acid methyl ester (3) or by (S)‐3‐N,N‐dibenzylamino‐4‐mesyloxybutanenitrile (6). Both intermediates should be approached from L‐aspartic acid 4 or L‐asparagine 5 through selective reduction of the α‐carboxyl group. It turned out that only nitrile 6 was suitable for the envisioned β‐amino acid synthesis, since alcohol 14 ‐ the synthetic precursor of 3 ‐ was unstable towards intramolecular nucleophilic attack to accomplish the chiral building block 15. Reaction of mesylate 6 with different ‘Gilman cuprates’ afforded the 3‐N,N‐dibenzylamino nitrile derivatives 22a‐c, which could be readily deprotected to give the target compounds 1a‐c in 23‐36% overall yield from asparagine. In contrast Me2Cu(CN)Li2 as an example for higher order ‘Lipshutz cuprates’ did not afford the desired substitution product 22a. The optical integrity of the synthesis was established by coupling of the methyl ester 24 with chiral 1‐phenylethyl isocyanate followed by appropriate NMR studies of carbamate 25.
Synthesis and hypocholesterolemic activity of some N‐diphenylmethylpiperazine derivatives
Authors: Alivert Antonio , Canals Francesc , Bonet Juan‐Julio , Gómez‐Parra Vicente , Sánchez‐Alonso Félix
Published: September 2010

The synthesis and preliminary assays as hypocholesterolemic agents of five N‐diphenylmethylpiperazines are described. The evaluations were carried out in hypercholesterolemic mice and two of these compounds were more effective than bezafibrate in the test employed. The di‐p‐chlorosubstituted compounds showed higher activity than their corresponding dechlorinated analogs.
Darstellung und Chemische Charakterisierung Des Calcium‐Agonisten Bay‐K‐8644 und Der Nebenprodukte Bei Der Hantzsch‐Synthese
Authors: Görlitzer Klaus , Schmidt Eckhardt
Published: September 2010

Die möglichen Nebenprodukte bei der Hantzsch‐Synthese des Calcium‐Agonisten Bay‐K‐8644 (1), die symmetrischen 1,4‐Dihydropyridine (DHP) 2 und 3, die 1,2‐DHP 12, die Tetrahydropyrimidine (THPM) 16, das Hydrobenzamid 18 und das Amarin 19 werden dargestellt. Als neuer Verbindungstyp wird das Nitroalkyl‐Aldimin 13 isoliert. Durch Dehydrierung werden die zu erwartenden Metabolite, die Pyridine 9 und 14 und das Pyrimidin 17 gewonnen. Die Nitroverbindungen 1, 9c und 12a werden mit Zink zu den Aminopyridinen 10 und 15 reduziert. 1 reagiert in MeOH mit UV A‐Licht zu den 3‐Pyridinolen 11a und b; aus 3 wird unter gleichen Bedingungen das 5‐Nitro‐3‐pyridinol 11c erhalten. Elektrochemische Untersuchungen beweisen, daβ die 1,4‐DHP stabiler sind als die 1,2‐DHP. Halbstufenpotential‐Struktur‐Beziehungen bei anodischen Oxidationen von DHP und THPM sowie bei kathodischen Reduktionen von Nitroverbindungen werden analysiert.
Platelet aggregation inhibiting and anticoagulant effects of oligoamines, XVI: Cytostatic and cytotoxic side effects of oligoamines
Authors: Rehse Klaus , Noack Birgit , Maurer Rainer , Hilgard Peter
Published: September 2010

Selected synthetic oligoamines were able to inhibit (IC50) the growth of leukemic L 1210 cells in concentrations between 4‐10 μmol/L. The essential structural features were at least two basic nitrogen functions in suitable distance, substituted with arylalkyl or alkyl groups. The favorable chain length is about eight carbon atoms. The cytostatic effect is complete after 30 min and cannot be washed out with buffer. Viability measurements showed that the leukemic cells were killed in a time dependent manner. As no influence on the cell nucleus could be observed this is most probably due to interaction with the cell membrane. When high local concentrations are applied in vivo, the oligoamines are toxic because of cytolytic properties. This toxicity can be overcome by administration of suitable prodrugs (LD50 > 1000 mg/kg).
Cyanamid als Seitenkettendienophil in der intramolekularen [4+2]‐Cycloaddition Mit 1,2,4,5‐Tetrazinen
Authors: Seitz Gunther , Yang Xiao‐Guang
Published: September 2010

Wir erweitern die Anwendungsbreite der intramolekularen Diels‐Alder‐Reaktion von 1,2,4,5‐Tetrazinen durch Einbeziehung von Cyanamid als Seitenkettendienophil und beschreiben Synthesewege zu neuen, anellierten Heterobicyclen wie 1,4‐Oxazino‐, 1,4‐Thiazino‐ und Pyrazino[2,3‐c]‐1,2,4‐triazinen 12a‐d, 17a bzw. 22c,d.
Pyridyl‐Substituierte Tetralonderivate: Eine Neue Klasse Nichtsteroidaler Aromatase‐Inhibitoren
Authors: Bayer Herbert , Hartmann Rolf W.
Published: September 2010

Ausgehend von Flavon und Flavanon, zwei Naturstoffen mit schwacher Aromatase‐inhibitorischer Wirkung, wurden die Verbindungen 1‐7 synthetisiert und auf ihre Hemmaktivität gegenüber Aromatase und Desmolase unlersucht. Mit Ausnahme von Verbindung 2 zeigen alle Derivate eine stärkere Aromatase‐Hemmung als die Ausgangsverbindungen und erweisen sich auch als potentere Aromatase‐Inhibitoren als Aminoglutethimid (AG), der einzige im Handel befindliche Wirkstoff. Im Gegensatz zu AG zeigen die Verbindungen 1 und 3‐7 keine Hemmung der Desmolase, die bei AG zu unerwünschten Nebenwirkungen führt.
1,3,2‐Benzodioxathiine Aus Aromatischen Enaminonen
Authors: Lowe Werner , Braden Thomas
Published: September 2010

Die bisher unbekannten 1,3,2‐Benzodioxathiine 5, 6 werden aus den Enaminonen 1, 2 durch Reaktion mit Chlorsulfonsäure oder Oleum erhalten. Die Verbindungen 5, 6 lassen sich in die Oxime 7, 8, in die Oximester 11, 12, in die 2,4‐Dinitrophenylhydrazone 13, 14 und in die Alkohole 15, 16 überführen.
1,4‐Dicarbonyl‐, 1,4,7‐Tricarbonyl‐Verbindungen und Cyclopentenone aus Etacrynsäure
Authors: Görlitzer Klaus , Bömeke Michael
Published: September 2010

Die Michael‐Addition von Nitroalkanen an Etacrynsäure 1 liefert die γ‐Nitroketone 2, 3 und 10. Aus diesen werden durch KMnO4‐Oxidation in Gegenwart von MgSO4 die 1,4‐Dicarbonylverbindungen 6 und 9 sowie das 1,4,7‐Triketon 11 dargestellt. 2 reagiert mit KMnO4/Borax zur γ‐Ketocarbonsäure 5. 5 ist auch durch Addition von HCN an 1 umd saure Hydrolyse des gebildeten Nitrils 4 zugänglich. Bei der alkalischen Verseifung von 4 wird dagegen das Phenol 8 gebildet. 2 wird durch alkalisches H2O2 zur Benzoesäure 7 abgebaut Durch intramolekulare Aldol‐Kondensation von 9 und 11 werden die Cyclopentenone 12 und 13 erhalten. 12 und 13 weisen eine unterschiedliche Lage der cyclischen Doppelbindung auf.
LDA‐Katalysierte Diastereoselektive Michael‐Additionen Mit Glycinderivaten: Synthese von 4‐Substituierten 3‐Aryl‐2‐N(Diphenyl‐Methylen)‐glutaminsäureestern und Ihre Umwandlung in 4‐Substituierte 3‐Aryl‐2‐Ethoxycarbonyl‐5‐Oxo‐Pyrrolidine
Authors: Pachaly Peter , Kang Hye‐Sook , Wahl Dirk
Published: September 2010

Es wird über die Synthese und Stereochemie von 4‐substituierten 3‐Aryl‐N(diphenylmethylen)glutaminsäureestem 3 durch LDA‐katalysierte Michael‐Addition von N(Diphenylmethylen)glycinester mit Benzylidenmalonsäureestern und 2‐Cyanzimisäureestem berichtet. Die nach Abspaltung der Schutzgruppe erhältlichen 4‐substituierten β‐Arylglutaminsäureester 4 lassen sich leicht zu 4‐substituierten 3‐Aryl‐2‐ethoxycarbonyl‐5‐oxo‐pyrrolidinen 5 cyclisieren.
Signalling mechanisms regulating axonal branching in vivo
Authors: Schmidt Hannes , Rathjen Fritz G.
Published: September 2010

Identification of the molecular mechanisms underlying axonal branching in vivo has begun in several neuronal systems, notably the projections formed by dorsal root ganglion (DRG) neurons or retinal ganglion cells (RGC). cGMP signalling is essential for sensory axon bifurcation at the spinal cord, whereas brain‐derived neurotrophic factor (BDNF) and ephrinA signalling establish position‐dependent branching of RGC axons. In the latter system, the degradation of specific signalling components, via the ubiquitin‐proteasome system, may provide an additional mechanism involved in axon branching of RGC. The process of arborisation is essential for neurons to innervate multiple targets and to build topographic maps. The various forms of branching found in different types of neurons are regulated by distinct signalling pathways activated by multiple extracellular cues in addition to axonal guidance factors. These signalling cascades, together with transcriptional programs, most likely interact and trigger the polymerisation or depolymerisation of the actin and tubulin cytoskeleton to regulate branching.
Upconversion: road to El Dorado of the fluorescence world
Authors: Ong Li Ching , Gnanasammandhan Muthu Kumara , Nagarajan Sounderya , Zhang Yong
Published: September 2010

Upconversion nanoparticles (UCNs), in the recent times have attracted attention due to their unique properties, which makes them ideal fluorophores for use in biological applications. There have been various reports on their use for targeted cell imaging, drug and gene delivery and also for diffuse optical tomography. Here we give a brief introduction on what are UCNs and the mechanism of upconversion, followed by a discussion on the biological applications of UCNs and further on what the future holds for UCNs. Copyright © 2010 John Wiley & Sons, Ltd.