bluuebunny/crossref_metadata_2025 huggingface dataset:
Subcomplexes of mitochondrial complex V reveal mutations in mitochondrial DNA
Authors: Smet Joél , Seneca Sara , De Paepe Boel , Meulemans Ann , Verhelst Helene , Leroy Jules , De Meirleir Linda , Lissens Willy , Van Coster Rudy
Published: October 2009

Complex V, site of the final step in oxidative phosphorylation, uses the proton gradient across the inner mitochondrial membrane for the production of ATP. It is a multi‐subunit complex composed of a catalytic domain (F1) and a membrane domain (F0) linked by two stalks. Subcomplexes of complex V containing the F1 domain have previously been reported in small series of patients. We report the results in tissue samples and/or cultured skin fibroblasts studied by blue native PAGE followed by activity staining in the gel. Catalytically active subcomplexes of complex V were detected in 66 tissues originating from 53 patients. In 29 of the latter (55%), a mitochondrial DNA (mtDNA) defect was identified. Twelve patients had a pathogenic point mutation in a mitochondrial tRNA, one a large mtDNA deletion, 12 showed mtDNA depletion and four had a mutation in the MT‐ATP6 gene. We conclude that the presence of subcomplexes of complex V is a valuable indicator in the detection of mtDNA defects.
A new multiplex for human identification using insertion/deletion polymorphisms
Authors: Pereira Rui , Phillips Christopher , Alves Cíntia , Amorim António , Carracedo Ángel , Gusmão Leonor
Published: October 2009

Human identification is usually based on the study of STRs or SNPs depending on the particular characteristics of the investigation. However, other types of genetic variation such as insertion/deletion polymorphisms (indels) have considerable potential in the field of identification, since they can combine the desirable characteristics of both STRs and SNPs. In this study, a set of 38 non‐coding bi‐allelic autosomal indels reported to be polymorphic in African, European, and Asian populations were selected. We developed a sensitive genotyping assay, which is able to characterize all 38 bi‐allelic markers using a single multiplex PCR and detected with standard CE analyzers. Amplicon length was designed to be shorter than 160 bp. Complete profiles were obtained using 0.3 ng of DNA, and full genotyping of degraded samples was possible in cases where standard STR typing had partially failed. A total of 306 individuals from Angola, Mozambique, Portugal, Macau, and Taiwan were studied and population data are presented. All indels were polymorphic in the three population groups studied and the random match probabilities of the set ranged in orders of magnitude from 10−14 to 10−15. Therefore, the indel‐plex represents a valuable approach in human identification studies, especially in challenging DNA cases, as a more straightforward and efficient alternative to SNP typing.
Applications of MALDI‐TOF MS to large‐scale human mtDNA population‐based studies
Authors: Cerezo María , Černý Viktor , Carracedo Ángel , Salas Antonio
Published: October 2009

Analysis of the mitochondrial DNA variation in populations is commonly carried out in many fields of biomedical research. We propose the analysis of mitochondrial DNA coding region SNP (mtSNP) variation to a high level of phylogenetic resolution based on MALDI‐TOF MS. The African phylogeny has been chosen to test the applicability of the technique but any other part of the worldwide phylogeny (or any other mtSNP panel) could be equally suitable for MALDI‐TOF MS genotyping. SNP selection thus aimed to fully cover all the mtSNPs defining major and minor branches of the known African tree, including, macro‐haplogroup L, and haplogroups M1, and U6. A total of 230 mtSNPs were finally selected. We used tests samples collected from two different African locations, namely, Mozambique and Chad Basin. Different internal genotyping controls and other indirect approaches (e.g. phylogenetic checking coupled with automatic sequencing) were used in order to evaluate the reproducibility of the technique, which resulted to be 100% using samples previously subjected to whole genome amplification. The advantages of the MALDI‐TOF MS are also discussed in comparison with other popular methods such as minisequencing, highlighting its high‐throughput nature, which is particularly suitable for case–control medical studies, forensic databasing or population and anthropological studies.
Ground‐motion attenuation relationship for the Sumatran megathrust earthquakes
Authors: Megawati Kusnowidjaja , Pan Tso‐Chien
Published: October 2009

A representative attenuation relationship is one of the key components required in seismic hazard assessment of a region of interest. Attenuation relationships for peak ground acceleration, peak ground velocity and response spectral accelerations for Sumatran megathrust earthquakes, covering Mw up to 9.0, are derived based on synthetic seismograms obtained from a finite‐fault kinematic model. The relationships derived are for very hard rock site condition and for a long‐distance range between 200 and 1500 km. They are then validated with recorded data from giant earthquakes on the Sumatran megathrust occurring since year 2000. A close examination of the recorded data also shows that spectral shapes predicted by most of the existing attenuation relationships and that specified in the IBC code are not particularly suitable for sites where potential seismic hazard is dominated by large‐magnitude, distant, earthquakes. Ground motions at a remote site are typically signified by the dominance of long‐period components with periods longer than 1 s, whereas the predominant periods from most of the existing attenuation relationships and the IBC code are shorter than 0.6 s. The shifting of response spectrum towards longer period range for distant earthquakes should be carefully taken into account in the formulation of future seismic codes for Southeast Asia, where many metropolises are located far from active seismic sources. The attenuation relationship derived in the present study can properly reproduce the spectral shape from distant subduction earthquakes, and could hopefully give insights into the formulation of future seismic codes. Copyright © 2009 John Wiley & Sons, Ltd.
Assessment of menthol mint collection for genetic variability and monoterpene biosynthetic potential
Authors: Shasany Ajit K. , Gupta Soni , Gupta Mahesh K. , Naqvi Ali A. , Bahl Janak R. , Khanuja Suman P. S.
Published: October 2009

Eighteen accessions of Mentha arvensis var. piperascens Holmes from the CIMAP collection (CIMAP/C01 to CIMAP/C18) consisting of wild collections and released varieties, their mutants, seed progeny and hybrids from the CIMAP gene bank were assessed for diversity through a combined morphochemical and molecular approach. Morphological characters, oil yield and essential oil components were taken into account to generate a cluster that outgrouped accession CIMAP/C05 from others. A total of 60 primers were used for RAPD and the tree generated after cluster analysis revealed accession CIMAP/C05 as the most diverse genotype. All the accessions exhibited differences in narrow range except CIMAP/C05. A wide range of compositional differences were observed in the essential oil profile of the genotypes indicating varying efficiencies of conversion of one component into other and/or existing metabolic blocks in the essential oil biosynthetic pathway in them. Copyright © 2009 John Wiley & Sons, Ltd.
High‐order shock capturing schemes for turbulence calculations
Authors: Lo S.‐C. , Blaisdell G. A. , Lyrintzis A. S.
Published: October 2009

This work investigates high‐order central compact methods for simulating turbulent supersonic flows that include shock waves. Several different types of previously proposed characteristic filters, including total variation diminishing, monotone upstream‐centered scheme for conservation laws, and weighted essentially non‐oscillatory filters, are investigated in this study. Similar to the traditional shock capturing schemes, these filters can eliminate the numerical instability caused by large gradients in flow fields, but they also improve efficiency compared with classical shock‐capturing schemes. Adding the nonlinear dissipation part of a classical shock‐capturing scheme to a central scheme makes the method suitable for incorporation into any existing central‐based high‐order subsonic code. The amount of numerical dissipation to add is sensed by means of the artificial compression method switch. In order to improve the performance of the characteristic filters, we propose a hybrid approach to minimize the dissipation added by the characteristic filter. Through several numerical experiments (including a shock/density wave interaction, a shock/vortex interaction, and a shock/mixing layer interaction) we show that our hybrid approach works better than the original method, and can be used for future turbulent flow simulations that include shocks. Copyright © 2009 John Wiley & Sons, Ltd.
Distinct MHC gene expression patterns during progression of melanoma
Authors: Degenhardt Yan , Huang Jia , Greshock Joel , Horiates Galene , Nathanson Katherine , Yang Xiaolu , Herlyn Meenhard , Weber Barbara
Published: October 2009

Abnormal expression of major histocompatibility complex (MHC) molecules in melanoma has been reported previously. However, the MHC molecule expression patterns in different growth phases of melanoma and the underlying mechanisms are not well understood. Here, we demonstrate that in vertical growth phase (VGP) melanomas, MHC genes are subject to increased rates of DNA copy number gains, accompanied by increased expression, in comparison to normal melanocytes. In contrast, MHC expression in metastatic melanomas drastically decreased compared to VGP melanomas, despite still prevalent DNA copy number gains. Subsequent investigations found that the master transactivator of MHC genes, CIITA, was also significantly downregulated in metastatic melanomas when compared to VGP melanomas. This could be one of the mechanisms accounting for the discrepancy between DNA copy number and expression level in metastatic melanomas, a potentially separate mechanism of gene regulation. These results infer a dynamic role of MHC function in melanoma progression. We propose potential mechanisms for the overexpression of MHC molecules in earlier stages of melanoma as well as for its downregulation in metastatic melanomas. © 2009 Wiley‐Liss, Inc.
Step‐by‐step: The effects of physical practice on the neural correlates of locomotion imagery revealed by fMRI
Authors: Ionta Silvio , Ferretti Antonio , Merla Arcangelo , Tartaro Armando , Romani Gian Luca
Published: October 2009

Previous studies have shown that mental imagery is a suitable tool to study the progression of the effect of practice on brain activation. Nevertheless, there is still poor knowledge of changes in brain activation patterns during the very early stages of physical practice. In this study, early and late practice stages of different kinds of locomotion (i.e., balanced and unbalanced) have been investigated using functional magnetic resonance imaging during mental imagery of locomotion and stance. During the task, cardiac activity was also recorded. The cerebral network comprising supplementary motor area, basal ganglia, bilateral thalamus, and right cerebellum showed a stronger activation during the imagery of locomotion with respect to imagery of stance. The heart beat showed a significant increase in frequency during the imagery of locomotion with respect to the imagery of stance. Moreover, early stages of practice determined an increased activation in basal ganglia and thalamus with respect to late stages. In this way, it is proposed the modulation of the brain network involved in the imagery of locomotion as a function of physical practice time. Hum Brain Mapp, 2010. © 2009 Wiley‐Liss, Inc.
Role of intratumoral lymphatic vessels in the lymph node dissemination of laryngopharyngeal squamous cell carcinoma
Authors: Hinojar‐Gutiérrez Adolfo , Fernández‐Contreras María Encarnación , Álvarez‐Carrillo Solssireé , Quintanilla Miguel , Gamallo Carlos
Published: October 2009

Background

The development of new markers for lymphatic endothelium allowed the study of intratumoral lymphatic microcirculation, as well as its association with lymph node metastasis.

Methods

In all, 120 patients with laryngopharyngeal squamous cell carcinoma (LPSCC) without previous treatment were retrospectively studied. The immunohistochemical determination of PA2.26 antigen/podoplanin was used to assess intratumoral lymphatic vessels (ILVs) in the primary tumor.

Results

Multivariate analysis revealed that lymph node metastasis was associated with tumor location (p = .001), differentiation grade (p = .02), and ILV (p = .013). Hypopharyngeal and supraglottic locations, poor grade of differentiation, and ILV, respectively, increased the risk of developing lymph node metastasis 13.5‐, 4.7‐, 5.2‐, and 3.2‐fold.

Conclusions

In our series, the presence of ILV in the primary tumor was an independent risk factor for the development of lymph node metastasis. The incorporation of ILV assessment into routine clinicopathological study might improve the evaluation of patients with LPSCC. © 2009 Wiley Periodicals, Inc. Head Neck, 2010
New insights in the vascular supply of the human parotid gland—Consequences for parotid gland‐sparing irradiation
Authors: van Holten Marjolein J. , Roesink Judith M. , Terhaard Chris H. J. , Braam Pètra M.
Published: October 2009

Background.

Xerostomia is caused by irradiation for head and neck cancer, depending on the dose to the parotid gland. To investigate which part of the parotid gland has to be spared with radiotherapy, detailed information about the vascular supply of the parotid gland is necessary.

Methods.

Arterial vessels of the head of a human cadaver were colored. A 3‐dimensional reconstruction of the parotid gland and the arterial vessels was made and analyzed.

Results.

Five arterial vessels were responsible for the vascular supply of the parotid gland: the posterior auricular artery, 2 branches so far unnamed, the superficial temporal artery, and the transverse facial artery. All arteries were branches off the external carotid artery, and supplied different parts of the parotid gland.

Conclusions.

This study describes the detailed vascular supply of the human parotid gland. These results may contribute to improve parotid sparing radiotherapy, thus reducing complications such as xerostomia in the future. © 2009 Wiley Periodicals, Inc. Head Neck, 2009
Identification of groundwater recharge sources and processes in a heterogeneous alluvial aquifer: results from multi‐level monitoring of hydrochemistry and environmental isotopes in a riverside agricultural area in Korea
Authors: Choi Byoung‐Young , Yun Seong‐Taek , Mayer Bernhard , Chae Gi‐Tak , Kim Kyoung‐Ho , Kim Kangjoo , Koh Yong‐Kwon
Published: October 2009

We evaluated sources and pathways of groundwater recharge for a heterogeneous alluvial aquifer beneath an agricultural field, based on multi‐level monitoring of hydrochemistry and environmental isotopes of a riverside groundwater system at Buyeo, Korea. Two distinct groundwater zones were identified with depth: (1) a shallow oxic groundwater zone, characterized by elevated concentrations of NO3− and (2) a deeper (>10–14 m from the ground surface) sub‐oxic groundwater zone with high concentrations of dissolved Fe, silica, and HCO3−, but little nitrate. The change of redox zones occurred at a depth where the aquifer sediments change from an upper sandy stratum to a silty stratum with mud caps. The δ18O and δ2H values of groundwater were also different between the two zones. Hydrochemical and δ18Oδ2H data of oxic groundwater are similar to those of soil water. This illustrates that recharge of oxic groundwater mainly occurs through direct infiltration of rain and irrigation water in the sandy soil area where vegetable cropping with abundant fertilizer use is predominant. Oxic groundwater is therefore severely contaminated by agrochemical pollutants such as nitrate. In contrast, deeper sub‐oxic groundwater contains only small amounts of dissolved oxygen (DO) and NO3−. The 3H contents and elevated silica concentrations in sub‐oxic groundwater indicate a somewhat longer mean residence time of groundwater within this part of the aquifer. Sub‐oxic groundwater was also characterized by higher δ18O and δ2H values and lower d‐excess values, indicating significant evaporation during recharge. We suggest that recharge of sub‐oxic groundwater occurs in the areas of paddy rice fields where standing irrigation and rain water are affected by strong evaporation, and that reducing conditions develop during subsequent sub‐surface infiltration. This study illustrates the existence of two groundwater bodies with different recharge processes within an alluvial aquifer. Copyright © 2009 John Wiley & Sons, Ltd.
The cofilin activity cycle in lamellipodia and invadopodia
Authors: Oser Matthew , Condeelis John
Published: October 2009

The actin severing protein cofilin is essential for directed cell migration and chemotaxis, in many cell types and is also important for tumor cell invasion during metastasis. Through its severing activity, cofilin increases the number of free barbed ends to initiate actin polymerization for actin‐based protrusion in two distinct subcellular compartments in invasive tumor cells: lamellipodia and invadopodia. Cofilin severing activity is tightly regulated and multiple mechanisms are utilized to regulate cofilin activity. In this prospect, we have grouped the primary on/off regulation into two broad categories, both of which are important for inhibiting cofilin from binding to F‐actin or G‐actin: (1) Blocking cofilin activity by the binding of cofilin to either PI(4,5)P2 at lamellipodia, or cortactin at invadopodia. (2) Blocking cofilin's ability to bind to actin via serine phosphorylation. Although the literature suggests that these cofilin regulatory mechanisms may be cell‐type dependent, we propose the existence of a common cofilin activity cycle in which both operate. In this common cycle, the mechanism used to initiate cofilin activity is determined by the starting point in the cycle in a given subcellular compartment. J. Cell. Biochem. 108: 1252–1262, 2009. © 2009 Wiley‐Liss, Inc.
Theoretical and kinetic study of the H + C2H5CN reaction
Authors: Sun Jingyu , Tang Yizhen , Sun Hao , Jia Xiujuan , Pan Xiumei , Wang Rongshun
Published: October 2009

The reaction of H radical with C2H5CN has been studied using various quantum chemistry methods. The geometries were optimized at the B3LYP/6‐311+G(d,p) and B3LYP/6‐311++G(2d,2p) levels. The single‐point energies were calculated using G3 and BMC‐CCSD methods based on B3LYP/6‐311++G(2d,2p) geometries. Four mechanisms were investigated, namely, hydrogen abstraction, C‐addition/elimination, N‐addition/elimination and substitution. The kinetics of this reaction were studied using the transition state theory and multichannel Rice‐Ramsperger‐Kassel‐Marcus methodologies over a wide temperature range of 200–3000 K. The calculated results indicate that C‐addition/elimination channel is the most feasible over the whole temperature range. The deactivation of initial adduct C2H5CHN is dominant at lower temperature with bath gas H2 of 760 Torr; whereas C2H5+HCN is the dominant product at higher temperature. Our calculated rate constants are in good agreement with the available experimental data. © 2009 Wiley Periodicals, Inc. J Comput Chem, 2010
Sorption of copper by a highly mineralized peat in batch and packed‐bed systems
Authors: Izquierdo Marta , Gabaldón Carmen , Marzal Paula , Sempere Feliu
Published: October 2009

BACKGROUND: The performance of peat for copper sorption was investigated in batch and fixed‐bed experiments. The effect of pH was evaluated in batch experiments and the experimental data were fitted to an equilibrium model including pH dependence. Hydrodynamic axial dispersion was estimated by tracing experiments using LiCl as a tracer. Six fixed‐bed experiments were carried out at copper concentrations between 1 and 60 mg dm−3 and the adsorption isotherm in dynamic mode was obtained. A mass transport model including convection–dispersion and sorption processes was applied for breakthrough curve modelling.

RESULTS: Maximum uptake capacities in batch mode were 22.0, 36.4, and 43.7 mg g−1 for pH values of 4.0, 5.0, and 6.0, respectively. Uptake capacities in continuous flow systems varied from 36.5 to 43.4 mg g−1 for copper concentrations between 1 and 60 mg dm−3. Dynamic and batch isotherms showed different shapes but a similar maximum uptake capacity. Sorbent regeneration was successfully performed with HCl. A potential relationship between dispersion coefficient and velocity was obtained with dispersion coefficients between 5.00 × 10−8 and 2.95 × 10−6 m2 s−1 for water velocities ranging between 0.56 × 10−4 and 5.03 × 10−4 m s−1. The mass transport model predicted both the breakpoints and the shape of the breakthrough curves.

CONCLUSIONS: High retention capacities indicate that peat can be used as an effective sorbent for the treatment of wastewater containing copper ions. Copyright © 2009 Society of Chemical Industry
Microwave photochemistry V: Low‐pressure batch and continuous‐flow microwave photoreactors with quartz mercury electrodeless discharge lamps. Photohydrolysis of mono‐chloroacetic acid
Authors: Církva Vladimír , Relich Stanislav , Hájek Milan
Published: October 2009

BACKGROUND: Low‐pressure batch and continuous‐flow microwave photoreactors were equipped with microwave powered quartz mercury electrodeless discharge lamps (Hg‐EDLs). Photohydrolysis of aqueous mono‐chloroacetic acid (MCAA) into hydroxyacetic acid and HCl was chosen as the model reaction to evaluate these photoreactors. The effects of operational parameters on the MCAA photolysis through a UV/MW process were investigated.

RESULTS: Studies were carried out at relatively high MCAA concentration (0.1 mol L−1). The photoreaction course was monitored by the pH change in the solution. The MCAA conversion was optimized as a result of a trade‐off between the thermal dependence of the photochemical quantum yield (which increases with increasing temperature) and the thermal dependence of the EDL light intensity of 254 nm line (which increases with decreasing temperature). The microwave photoreactors made it possible to study the temperature dependence of MCAA photohydrolysis.

CONCLUSION: It was found that operational parameters (i.e. reaction temperature, quantum yield) had important effects on photoefficiency. Photohydrolysis of MCAA in the microwave photoreactors can be enhanced by the UV/MW system. The results of conversions (in 120 min) for the particular photoreactor set‐ups show that the best reaction conditions for MCAA photolysis were obtained in the low‐pressure batch microwave photoreactor (the conversion was 46% at 80 °C). Copyright © 2009 Society of Chemical Industry
A single‐step preparation of thiazolo[5,4‐b]pyridine‐ and thiazolo[5,4‐c]pyridine derivatives from chloronitropyridines and thioamides, or thioureas
Authors: Sahasrabudhe Kiran P. , Angels Estiarte M. , Tan Darlene , Zipfel Sheila , Cox Matthew , O'Mahony Donogh J. R. , Edwards William T. , Duncton Matthew A. J.
Published: October 2009

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A one‐step synthesis of thiazolo[5,4‐b]pyridines from an appropriately substituted chloronitropyridine and thioamide, or thiourea, is presented. In particular, the reaction was used to prepare a large number of 6‐nitrothiazolo[5,4‐b]pyridine derivatives, bearing hydrogen, alkyl, substituted alkyl, cycloalkyl, aryl, heteroaryl, and amine substituents at the 2‐position. The reaction could also be extended to produce a thiazolo[4,5‐c]pyridine derivative and thiazolo[5,4‐b]pyridines with alternative substituents on the pyridinoid ring. J. Heterocyclic Chem., (2009).
Abdominal muscle and epipubic bone function during locomotion in Australian possums: Insights to basal mammalian conditions and eutherian‐like tendencies in Trichosurus
Authors: Reilly Stephen M. , McElroy Eric J. , White Thomas D. , Biknevicius Audrone R. , Bennett Michael B.
Published: October 2009

Mammals have four hypaxial muscle layers that wrap around the abdomen between the pelvis, ribcage, and spine. However, the marsupials have epipubic bones extending anteriorly into the ventral hypaxial layers with two additional muscles extending to the ventral midline and femur. Comparisons of South American marsupials to basal eutherians have shown that all of the abdominal hypaxials are active bilaterally in resting ventilation. However, during locomotion marsupials employ an asymmetrical pattern of activity as the hypaxial muscles form a crosscouplet linkage that uses the epipubic bone as a lever to provide long‐axis support of the body between diagonal limb couplets during each step. In basal eutherians, this system shifts off the femur and epipubic bones (which are lost) resulting in a shoulder to pelvis linkage associated with shifts in both the positions and activity patterns of the pectineus and rectus abdominis muscles during locomotion. In this study, we present data on hypaxial function in two species (Pseudocheirus peregrinus and Trichosurus vulpecula) representing the two major radiations of possums in Australia: the Pseudocheiridae (within the Petauroidea) and the Phalangeridae. Patterns of gait, motor activity, and morphology in these two Australian species were compared with previous work to examine the generality of 1) the crosscouplet lever system as the basal condition for the Marsupialia and 2) several traits hypothesized to be common to all mammals (hypaxial tonus during resting ventilation, ventilation to step synchrony during locomotion, and bilateral transversus abdominis activity during locomotor expiration). Our results validate the presence of the crosscouplet pattern and basic epipubic bone lever system in Australian possums and confirm the generality of basal mammalian patterns. However, several novelties discovered in Trichosurus, reveal that it exhibits an evolutionary transition to intermediate eutherian‐like morphological and motor patterns paralleling many other unique features of this species. J. Morphol., 2010. © 2009 Wiley‐Liss, Inc.
Sequence determination of αs1‐casein isoforms from donkey by mass spectrometric methods
Authors: Cunsolo Vincenzo , Cairone Elisa , Fontanini Debora , Criscione Andrea , Muccilli Vera , Saletti Rosaria , Foti Salvatore
Published: October 2009

Four co‐eluting components, with experimentally measured Mr of 23 658, 23 786, 24 278 and 24 406 Da, were detected by reversed‐phase high‐performance liquid chromatography (RP‐HPLC) and matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOF MS) analysis in the dephosphorylated casein fraction of a milk sample collected at middle lactation stage from an individual donkey belonging to the Ragusano breed. By coupling RP‐HPLC, two‐dimensional polyacrylamide gel electrophoresis (2D‐PAGE), enzymatic digestions, MALDI‐TOF MS and capillary RP‐HPLC/nano‐electrospray ionization tandem mass spectrometry (nESI‐MS/MS) analyses, the four components were identified as donkey's αs1‐CNs and their sequences completely characterized, using the known mare's αs1‐CN (GenBank Acc. No. AAK83668; Mr 23750.7 Da) as reference. The proteins with Mr of 23 786 and 23 658 Da differ in the presence of a glutamine residue at position 83 in the full‐length component and present the amino acid substitutions Q8→H and H115→Y with respect to the mare's αs1‐CN. The other two components with Mr 24 406 and 24 278 Da, which also differ in the presence of a glutamine residue at position 88 in the full‐length component, show the insertion of the pentapeptide HTPRE between Leu33 and the Glu34. The two αs1‐CNs bearing the pentapeptide insertion were named variants A (202 amino acids; Mr 24 406) and A1 (201 amino acids; Mr 24 278), whereas the two αs1‐CNs without the pentapeptide were named variants B (197 amino acids; Mr 23 786) and B1 (196 amino acids; Mr 23 658). Copyright © 2009 John Wiley & Sons, Ltd.
Generation and dissociation of oxygen‐ and chloride‐bridged iron(III) and manganese(III) tetraphenylporphyrin dimer ions in the gas phase
Authors: Gozet Tuba , Huynh Lise , Bohme Diethard K.
Published: October 2009

Electrospray ionization mass spectrometry (ESI/MS) has allowed the discovery of novel dimer ions emerging from solutions of metalloporphyrin salts and their investigation by collision‐induced dissociation (CID) with N2 molecules. ESI mass spectra have been recorded for the formation of the oxygen or chloride‐bridged dimer ions [(FeTPP)2OH]+, [(MnTPP)2OH]+, [(FeTPP)2Cl]+ and [(MnTPP)2Cl]+ derived from various solutions of FeTPPCl and MnTPPCl salts. The CID of [(FeTPP)2OH]+ proceeds mainly by neutral loss of (FeTPP)OH to form [FeTPP]+ and, to a minor extent, to form the charge‐reversed products. The CID of [(MnTPP)2OH]+ exhibits exclusively the product ion [MnTPP]+ by loss of neutral (MnTPP)OH. [(FeTPP)2Cl]+ and [(MnTPP)2Cl]+ dissociate by loss of (Fe/MnTPP)Cl to give rise to [Fe/MnTPP]+. [(FeTPP)2O]+ and [(FeTPP)2OH]+ were generated from a solution of the dimer, (FeTPP)2O. Dissociation of [(FeTPP)2O]+ yields two product ions, [FeTPP]+ and [(FeTPP)O]+, with higher onsets compared to the equivalent fragments formed from [(FeTPP)2OH]+. Copyright © 2009 John Wiley & Sons, Ltd.
Multivariate data analysis for Raman spectroscopic imaging
Authors: Shinzawa Hideyuki , Awa Kimie , Kanematsu Wataru , Ozaki Yukihiro
Published: October 2009

This article reviews the analytic techniques for Raman spectroscopic imaging with emphasis on chemometrics. Key information included in Raman spectra is often distributed broadly throughout the dataset. It is possible to condense the information into a very compact matrix representation by a chemometric technique of factor analysis such as principal component analysis (PCA) or self‐modeling curve resolution (SMCR). PCA yields two matrices called scores and loadings which complementarily represent the entire features broadly distributed in the dataset. This concept can be further extended to other forms of data transformation schemes, including bilinear data decomposition based on SMCR analysis. SMCR offers a firmer model which is chemically or physically interpretable. The information derived from these techniques readily brings useful insight into building a mechanistic model for understanding complex phenomena studied by Raman spectroscopy. Illustrative examples are given for applications of both PCA and SMCR to Raman imaging of pharmaceutical tablets. Copyright © 2009 John Wiley & Sons, Ltd.
3D Hollow Microspheres Assembled from 1D Polyaniline Nanowires through a Cooperation Reaction
Authors: Zhu Ying , Ren Guanqiao , Wan Meixiang , Jiang Lei
Published: October 2009

Novel 3D hollow spheres (diameter ≈525 nm, thickness ≈70 nm) self‐assembled from 1D PANI nanofibers (diameter ≈17 nm) with conductivity of 1.11 × 10−1 S · cm−1 are synthesized template‐free by using FeCl3 and salicylic acid as the oxidant and dopant, respectively. In this method, the reaction of aniline with FeCl3 and SA to form conductive PANI and the reaction of SA with FeCl3 to produce a color complex, assigned as Fe(OR)2+, wherein OR represents the ionized phenol, coexist. The coexistence of two reactions results in a cooperative effect of the micelle, where aniline/SA acts as as a soft template of the nanofibers and the color complex as a soft‐template of the spheres, to allow the self‐assembly of complex micro/nanostructures via hydrogen bonding as the driving force.

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Vitrification and Devitrification during the Non‐Isothermal Cure of a Thermoset. Theoretical Model and Comparison with Calorimetric Experiments
Authors: Fraga Iria , Montserrat Salvador , Hutchinson John M.
Published: October 2009

The processes of vitrification and devitrification that occur during the non‐isothermal cure of a cross‐linking system are studied in terms of their dependence on frequency. Experimental results are obtained by TOPEM, a new multi‐frequency temperature modulated differential scanning calorimetry (TMDSC) technique, and a simulation with MATLAB was used to model the vitrification and devitrification times as a function of the frequency and heating rate. Simulations were made for five different velocities of scan. Other parameters, such as the exponents in the Kamal equation, λ in the DiBenedetto equation, and the activation energy for the frequency dependence of Tg, were also considered. The experimental and simulated results were found to be in good agreement and some advantages of the TOPEM technique are discussed.

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Finite volume distance field and its application to medial axis transforms
Authors: Xia Hao , Tucker Paul G.
Published: October 2009

Accurate and efficient computation of the nearest wall distance d (or level set) is important for many areas of computational science/engineering. Differential equation‐based distance/level set algorithms, such as the hyperbolic‐natured Eikonal equation, have demonstrated valuable computational efficiency. Here, in the context, as an ‘auxiliary’ equation to the main flow equations, the Eikonal equation is solved efficiently with two different finite volume approaches (the cell‐vertex and cell‐centered). The application of the distance solution is studied for various geometries. Moreover, a procedure using the differential field to obtain the medial axis transform (MAT) for different geometries is presented. The latter provides a skeleton representation of geometric models that has many useful analysis properties. As an alternative to other methods, the current d‐MAT procedure bypasses difficulties that are usually encountered by pure geometric methods (e.g. the Voronoi approach), especially in three dimensions, and provides better accuracy than pure thinning methods. It is also shown that the d‐MAT approach provides the potential to sculpt/control the MAT form for specialized solution purposes. Copyright © 2009 John Wiley & Sons, Ltd.
On the decomposition of generalized eigenproblems for the free vibration analysis of cyclically symmetric finite element models
Authors: Koohestani K.
Published: October 2009

Free vibration analysis is a major part of any dynamic analysis. Natural frequencies and related mode shapes may be obtained from free vibration analysis as the solutions of generalized eigenproblems. Although the eigensolutions of large‐scale structures require large computational efforts, these solutions may be achieved simply for symmetric structures. We present an efficient method for the decomposition of generalized eigenproblems related to finite element models with cyclic symmetry (having nodes at the axis of symmetry) into eigensubproblems with significantly smaller dimensions. This decomposition is obtained by block diagonalization of a matrix with a special pattern known as a block circulant, using the concept of the Kronecker product and similarity transformations. The proposed method is applied to three finite element models discretized by triangular and four‐node quadrilateral plate and shell elements, and its efficiency, accuracy and simplicity are evaluated. Copyright © 2009 John Wiley & Sons, Ltd.
Medizinische Chemie der Wirkstoffe gegen Malaria. Wirk‐ und Resistenzmechanismen
Authors: Schlitzer Martin
Published: October 2009

Das Arsenal, das zum medikamentösen Kampf gegen die Malaria‐Parasiten zur Verfügung steht, ist vergleichsweise begrenzt. Es handelt sich um die 4‐Aminochinoline Chloroquin und Amodiaquin, die Arylaminoalkohole Chinin, Mefloquin und Lumefantrin, das Endoperoxid Dihydroartemisinin und seine beiden Prodrugs Artemether und Artesunat, die Antifolat‐Kombination Sulfadoxin/Pyrimethamin, sowie das 8‐Aminochinolin Primaquin. Relativ neu und mit einem neuartigen Wirkprinzip ist die Kombination Atovaquon/Proguanil. Auch manche Antibiotika, vor allem Doxycyclin und Clindamycin, töten die Parasiten.
Affen, Menschen und Malaria. Affenmalaria – auch für den Menschen gefährlich!
Authors: Schlitzer Martin
Published: October 2009

Malaria ist eine der am weitesten verbreiteten Infektionserkrankungen unter den Wirbeltieren. Sie befällt Vögel, Reptilien und Säugetiere, unter diesen vorwiegend Nager und Primaten. Heute sind mehr als 30 Spezies der Gattung Plasmodium bekannt, die Primaten befallen, davon sind vier Spezies (P. falciparum, P. vivax, P. ovale und P. malariae) die Malaria‐Parasiten des Menschen.
Erfolgreiches Konzept: Proteasen als Zielstrukturen für Antiinfektiva. Neue Angriffspunkte in der Infektionstherapie
Authors: Schirmeister Tanja , Welker Armin
Published: October 2009

Virale Serin‐ und Cystein‐Proteasen, die das große virale Vorläuferprotein in strukturelle und nicht‐strukturelle Proteine spalten, sind neue Zielenzyme antiviraler Arzneistoffe. Eine Hemmung der Proteasen verhindert die Replikation der Viren. Beispiele für neue antivirale Arzneistoffe in der klinischen Prüfung sind die gegen die HCV‐Protease gerichteten Peptidylketoamide Telaprevir und Boceprevir oder die makrozyklischen Sulfonamide TMC‐435350 und ITMN‐191. Protozoen und Parasiten exprimieren ein ganzes Arsenal an Proteasen, sehr häufig Aspartat‐ und Cystein‐Proteasen, die essenzielle Rollen bei der Invasion in die Wirtszellen, beim Katabolismus der Wirtsproteine (z.B. Hämoglobinabbau als Aminosäurequelle), der Differenzierung, der Freisetzung aus den Wirtszellen und der Ausschaltung der Immunantwort des Wirtes spielen. Ein irreversibler Hemmstoff in präklinischer Entwicklung mit antitrypanosomaler und antischistosomaler Wirkung ist das Vinylsulfon CRA‐3316 und davon abgeleitete reversible Thiosemicarbazon‐Derivate.
Neue Hoffnung auf eine Malaria‐Impfung
Authors: Holzgrabe Ulrike
Published: October 2009

Malaria ist auch heute noch weltweit eine der am weitesten verbreiteten parasitären Erkrankungen, insbesondere in Afrika südlich der Sahara. Sie verursacht jährlich 300 Millionen Neuerkrankungen und 1 bis 3 Millionen Tote, zumeist unter Kindern im Alter unter 5 Jahren.
Comparative proteome and transcriptome analyses of embryonic stem cells during embryoid body‐based differentiation
Authors: Fathi Ali , Pakzad Mohammad , Taei Adele , Brink Thore C. , Pirhaji Leila , Ruiz Guifré , Sharif Tabe Bordbar Mohammad , Gourabi Hamid , Adjaye James , Baharvand Hossein , Hosseini Salekdeh Ghasem
Published: October 2009

Gene expression analyses of embryonic stem cells (ESCs) will help to uncover or further define signaling pathways and molecular mechanisms involved in the maintenance of self‐renewal and pluripotency. We employed a 2‐DE‐based proteomics approach to analyze human ESC line, Royan H5, in undifferentiated cells and different stages of spontaneous differentiation (days 3, 6, 12, and 20) by embryoid body formation. Out of 945 proteins reproducibly detected on gels, the expression of 96 spots changed during differentiation. Using MS, 87 ESC‐associated proteins were identified including several proteins involved in cell proliferation, cell apoptosis, transcription, translation, mRNA processing, and protein folding. Transcriptional changes accompanying differentiation of Royan H5 were also analyzed using microarrays. We developed a comprehensive data set that shows the use of human ESC lines in vitro to mimic gastrulation and organogenesis. Our results showed that proteomics and transcriptomics data are complementary rather than duplicative. Although regulation of many genes during differentiation were observed only at transcript level, modulation of several proteins was revealed only by proteome analysis.
An environmentally benign room temperature aqueous homo‐ and copolymerization of styrene and methylmethacrylate catalyzed by [Cp2TiCl2]/NaBPh4
Authors: De Sudip K. , Bhattacharjee Manish
Published: October 2009

[Cp2TiCl2] has been found to be an effective precatalyst for room temperature aqueous homo‐ and copolymerization of methyl methacrylate and styrene in the presence of a cocatalyst, NaBPh4 and an emulsifier, sodium n‐dodecyl sulfate. The polymers obtained are of high molecular weight with low molecular weight distribution. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 6496–6503, 2009
Are o‐nitrobenzyl (meth)acrylate monomers polymerizable by controlled‐radical polymerization?
Authors: Schumers Jean‐Marc , Fustin Charles‐André , Can Aydin , Hoogenboom Richard , Schubert Ulrich S. , Gohy Jean‐François
Published: October 2009

We report on the controlled‐radical polymerization of the photocleavable o‐nitrobenzyl methacrylate (NBMA) and o‐nitrobenzyl acrylate (NBA) monomers. Atom transfer radical polymerization (ATRP), reversible addition‐fragmentation chain transfer polymerization (RAFT), and nitroxide‐mediated polymerization (NMP) have been evaluated. For all methods used, the acrylate‐type monomer does not polymerize, or polymerizes very slowly in a noncontrolled manner. The methacrylate‐type monomer can be polymerized by RAFT with some degree of control (PDI ∼ 1.5) but leading to molar masses up to 11,000 g/mol only. ATRP proved to be the best method since a controlled‐polymerization was achieved when conversions are limited to 30%. In this case, polymers with molar masses up to 17,000 g/mol and polydispersity index as low as 1.13 have been obtained. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 6504–6513, 2009
Copper catalyzed atom transfer radical copolymerization of glycidyl methacrylate and 2‐ethylhexyl acrylate
Authors: Haloi Dhruba J. , Roy Santanu , Singha Nikhil K.
Published: October 2009

This investigation reports the atom transfer radical copolymerization (ATRcP) of glycidyl methacrylate (GMA) and 2‐ethylhexyl acrylate (EHA). Poly(glycidyl methacrylate) (PGMA) has easily transformable pendant oxirane group and poly(2‐ethylhexyl acrylate) (PEHA) has very low Tg. They are the important components of coating and adhesive materials. Copolymerization of GMA and EHA was carried out in bulk and in toluene at 70 °C at different molar feed ratios using CuCl as catalyst in combination with 2,2′‐bypyridine (bpy) as well as N,N,N′,N″,N″‐pentamethyl diethylenetriamine (PMDETA) as ligand. The molecular weight (Mn) and the polydispersity index (PDI) of the polymers were determined by GPC analysis. The molar composition of the copolymers was determined by 1H NMR analysis. The reactivity ratios of GMA (r1) and EHA (r2) were determined using Finemann‐Ross and Kelen‐Tudos linearization methods and those had been compared with the literature values for conventional free radical copolymerization. The thermal properties of the copolymers were studied by DSC and TGA analysis. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 6526–6533, 2009
Comparison of surface confined ATRP and SET‐LRP syntheses for a series of amino (meth)acrylate polymer brushes on silicon substrates
Authors: Ding Shijie , Floyd J. Alaina , Walters Keisha B.
Published: October 2009

A series of poly(amino (meth)acrylate) brushes, poly(2‐(dimethylamino)ethyl methacrylate) (PDMAEMA), poly(2‐(diethylamino)ethyl methacrylate) (PDEAEMA), poly(2‐(dimethylamino)ethyl acrylate) (PDMAEA), poly(2‐(tert‐butylamino)ethyl methacrylate) (PTBAEMA), has been synthesized via surface‐confined controlled/living radical polymerizations using surface‐confined initiator from silane self‐assembled monolayers (SAMs) on silicon (Si) wafer substrates. Chemical methods and efficacies for two types of living radical polymerization, atom transfer radical (ATRP) and single electron transfer (SET‐LRP), are described and contrasted for the surface confined polymerization of poly(amino (meth)acrylate)s. Effects of solvent, catalyst/ligand system, and temperature on polymerization success were examined. Chemical compositions after each reaction step were characterized with FTIR spectroscopy, contact angle goniometry, and X‐ray photoelectron spectroscopy while the SAM and polymer brush thicknesses were measured with spectroscopic ellipsometry. For the first time, this study demonstrates successful surface‐confined polymerization of a series of poly(amine (meth)acrylate) brushes from Si‐SAM substrates using a copper metal electron donor catalyst. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 6552–6560, 2009
Kinetic study of H‐atom transfer in imidazoline‐, imidazolidine‐, and pyrrolidine‐based alkoxyamines: Consequences for nitroxide‐mediated polymerization
Authors: Edeleva Mariya V. , Kirilyuk Igor A. , Zubenko Dmitry P. , Zhurko Irina F. , Marque Sylvain R. A. , Gigmes Didier , Guillaneuf Yohann , Bagryanskaya Elena G.
Published: October 2009

The H‐atom transfer reaction was studied for a series of imidazoline, imidazolidine, and pyrrolidine‐based alkoxyamines containing either isobutyrate‐2‐yl or 1‐phenylethyl alkyl fragments. The CO bond homolysis rate constants and activation energies were determined by 1H NMR product analysis as a function of temperature. Inter‐ and intramolecular H‐atom transfer reactions were distinguished by examination of alkoxyamine thermolysis products in the absence and in the presence of a radical scavenger (thiophenol or deuterated styrene). A correlation between the structure of the nitroxyl fragment of alkoxyamine and the H‐transfer reaction was found. The high steric demands of the substituents on the nitroxyl part of the isobutyrate‐2‐yl alkoxyamine decrease both types of reaction. For alkoxyamines containing the 1‐phenylethoxyamines, neither inter‐ nor intramolecular H‐atom transfer was observed. Controlled polymerization of methylmethacrylate initiated with imidazoline‐based alkoxyamine was observed, although the polymer obtained was not living. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 6579–6595, 2009
Facile synthesis of well‐defined pH‐liable Schiff‐base‐type photosensitive polymers via visible‐light‐activated ambient temperature RAFT polymerization
Authors: Luo Qing , Zheng Haimei , Peng Ye , Gao Huan , Lu Lican , Cai Yuanli
Published: October 2009

Inspired by the structure character and photosensitive molecular mechanism of natural rhodopsin or bacteriorhodopsin, a novel pH‐liable photosensitive polymer whose chromophores directly bind with Schiff base linkages was designed. Accordingly, 2‐((3‐phenylallylidene)amino)ethyl methacrylate (PAAEMA), 2‐((3‐(4‐fluorophenyl)allylidene)amino)ethyl methacrylate (FPAAEMA), and 2‐((3‐(4‐methoxyphenyl)allylidene)amino)ethyl methacrylate (MPAAEMA) monomers were synthesized. These monomers were polymerized upon irradiating with mild visible light at ambient temperature. The results indicate that Schiff base linkages of these monomers are stable under such mild polymerizing conditions, and the weak absorption of dithioester functionalities in the visible wave range leads to a rapid and well‐controlled RAFT polymerization. The polymerization rate slows down but initialization period significantly shortens on increasing the feed molar ratio of monomer. The pendant electron‐withdrawing‐group‐substituted chromophore improves the reactivity of monomer, but electron‐donating‐group‐substituted chromophore significantly inactivates monomer. Glycidyl methacrylate (GMA) may well incorporate in this polymer via RAFT random copolymerization of PAAEMA and GMA monomers due to the comparable reactivity ratios of this monomer pair. PolyMPAAEMA exhibits reversible fluorescence emitting or quenching upon deprotonating or protonating the Schiff base linkages. This fluorescence behavior may be of interest in the fabrication of pH‐responsive photosensors, light modulators, or actuators. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 6668–6681, 2009