bluuebunny/crossref_metadata_2025 huggingface dataset:
Cell proliferation inhibition and antitumor activity of novel alkyl series of diorganotin(IV) compounds
Authors: Koch Biplob , Baul Tushar S. Basu , Chatterjee Anupam
Published: July 2007

Diorganotin(IV) compounds, R2SnCl2 are often tetrahedral, and structurally resemble the active platinum compounds, i.e. cisplatin, and consequently a large number of such complexes have been tested for antitumor activity. A structural correlation with biological activity for diorganotin(IV) complexes has shown that active species are associated with complexes having Sn–N bonds longer than 2.39 Å which in turn determines the formation of a tin–DNA complex. In view of these, a series of diorganotin(IV) dichloride complexes of N‐(2‐pyridylmethylene)arylamine (nitrogen‐chelating ligands) has been synthesized and characterized on the basis of IR, NMR and 119Sn‐Mössbauer studies. In the present study, an attempt was made to determine the comparative antiproliferative and antitumor effect of diorganotin(IV) complexes with different alkyl groups [Me2SnCl2·L1 (OTC‐1), Et2SnCl2·L2 (OTC‐2) and nBu2SnCl2·L2 (OTC‐3)]. The present study in human lymphocytes demonstrated that these diorganotin(IV) complexes could block the cell cycle progression and induce sister chromatid exchanges (SCEs) significantly, however, with respect to the induction of chromosome aberrations (CAs) it was very mild. Both the levels of p53 and p16 proteins were raised after diorganotin(IV) treatment and such induction was maximum in the OTC‐3 treated samples. The antitumor activity was determined in accordance with the US National Cancer Institute (NCI) standard protocol for primary screening in Dalton's lymphoma that was maintained by serial intraperitoneal transplantation. The T/C (treated/control) value was increased (186% with OTC‐3) when diorganotin(IV) was given after transplantation. The data suggest that the OTC‐3 has better antiproliferative and antitumor activity and endogenous glutathione level has no influence on the effect of OTC‐3. Copyright © 2007 John Wiley & Sons, Ltd.
Cytogenetic analysis of tannery workers in Morocco
Authors: Hilali A. , Anane R. , Jaaouani N. , Creppy E. E. , Verschaeve L.
Published: July 2007

This study investigated the possible genetic effects in blood lymphocytes of tannery workers from Morocco being professionally exposed to multiple chemical agents. It was shown that the frequencies of cells with chromosome aberrations and micronuclei were significantly increased in the lymphocytes of the workers compared with the frequencies found in an unexposed control population. Copyright © 2007 John Wiley & Sons, Ltd.
Increased resorptive activity and accompanying morphological alterations in osteoclasts derived from the oim/oim mouse model of osteogenesis imperfecta
Authors: Zhang Hao , Doty Stephen B. , Hughes Christine , Dempster David , Camacho Nancy Pleshko
Published: July 2007

The current study addresses whether alterations in osteoclasts (OCs) derived from oim/oim mice, an established model of moderate‐to‐severe OI, are present. Bone marrow cells from oim/oim and wildtype (+/+) mice were cultured on bone slices in the presence of MCSF and RANKL and evaluated at days 0, 1, 2, 4, and 7. OCs were identified by tartrate‐resistant acid phosphatase (TRAP) staining, and bone slice resorption pits were analyzed by reflection microscopy. Flow cytometry was used to examine CD51 (integrin αV) and CD61 (integrin β3) markers. Confocal microscopy was used to assess changes in OC morphology and resorption. There was no difference between the OC precursors of the two genotypes in expression of CD51 and CD61 markers. At day 2, the bone slices seeded with oim/oim cells had a greater percentage of mononuclear cells associated with resorption pits compared to +/+ bone slices. At day 4, the diameter and area of oim/oim OCs were larger compared to the +/+ OCs, and the number of nuclei per OC was also greater for the oim/oim group. At day 7, the oim/oim OCs contained more F‐actin rings compared to the +/+ OCs, and the number of OCs in the oim/oim group was greater compared to the +/+ group. The resorbed area of bone slices for the oim/oim group was also greater compared to the +/+ group at day 7. In conclusion, oim/oim mononuclear resorbing cells and OCs showed cellular changes and greater resorptive activity compared to +/+ cells, features that likely contribute to dysregulated bone remodeling in OI. J. Cell. Biochem. 102: 1011–1020, 2007. © 2007 Wiley‐Liss, Inc.
Marlin‐1 is expressed in testis and associates to the cytoskeleton and GABAB receptors
Authors: Vidal René L. , Ramírez Alfredo , Castro Maite , Concha Ilona I. , Couve Andrés
Published: July 2007

Marlin‐1 is a GABAB receptor and Jak tyrosine kinase‐binding protein that also associates with RNA and microtubules. In humans and rodents, expression of Marlin‐1 is predominantly restricted to the brain, but expression in lymphoid cells has also been reported. Here, we have studied the distribution of Marlin‐1 in testis and spermatozoa. Our results indicate that Marlin‐1 is highly expressed in testis. The protein is abundant in spermatogonia, spermatocytes, spermatozoa, and Sertoli cells. We also have studied the subcellular distribution in spermatozoa. Marlin‐1 is present in the tail and to a lesser degree in the head of the sperm cell. Finally, we have explored two protein interactions. Our findings demonstrate that Marlin‐1 associates with a microtubule fraction and with GABAB receptors in testis suggesting that the set of protein interactions of Marlin‐1 are conserved in different tissues. J. Cell. Biochem. 103: 886–895, 2008. © 2007 Wiley‐Liss, Inc.
NCX3 is a major functional isoform of the sodium–calcium exchanger in osteoblasts
Authors: Sosnoski Donna M. , Gay Carol V.
Published: July 2007

The calcium phosphate‐based skeleton of vertebrates serves as the major reservoir for metabolically available calcium ions. The skeleton is formed by osteoblasts which first secrete a proteinaceous matrix and then provide Ca++ for the calcification process. The two calcium efflux ports found in most cells are the plasma membrane Ca‐ATPase (PMCA) and the sodium–calcium exchanger (NCX). In osteoblasts, PMCA and NCX are located on opposing sides of the cell with NCX facing the mineralizing bone surface. Two isoforms of NCX have been identified in osteoblasts NCX1, and NCX3. The purpose of this study was to determine the extent to which each of the two NCX isoforms support delivery of Ca++ into sites of calcification and to discern if one could compensate for the other. SiRNA technology was used to knockdown each isoform separately in MC3T3‐E1 osteoblasts. Osteoblasts in which either NCX1 or NCX3 was impaired were tested for Ca++ efflux using the Ca++ specific fluorophore, fluo‐4, in a sodium‐dependent calcium uptake assay adapted for image analysis. NCX3 was found to serve as a major contributor of Ca++ translocation out of osteoblasts into calcifying bone matrix. NCX1 had little to no involvement. J. Cell. Biochem. 103: 1101–1110, 2008. © 2007 Wiley‐Liss, Inc.
Chromatin organization and nuclear microenvironments in cancer cells
Authors: He Shihua , Dunn Katherine L. , Espino Paula S. , Drobic Bojan , Li Lin , Yu Jenny , Sun Jian‐Min , Chen Hou Yu , Pritchard Susan , Davie James R.
Published: July 2007

Nuclear morphometric descriptors such as nuclear size, shape, DNA content and chromatin organization are used by pathologists as diagnostic markers for cancer. However, our knowledge of events resulting in changes in nuclear shape and chromatin organization in cancer cells is limited. Nuclear matrix proteins, which include lamins, transcription factors (Sp1) and histone modifying enzymes (histone deacetylases), and histone modifications (histone H3 phosphorylation) have roles in organizing chromatin in the interphase nucleus, regulating gene expression programs and determining nuclear shape. Histone H3 phosphorylation, a downstream target of the Ras‐mitogen activated protein kinase pathway, is involved in neoplastic transformation. This article will review genetic and epigenetic events that alter chromatin organization in cancer cells and the role of the nuclear matrix in determining nuclear morphology. J. Cell. Biochem. 104: 2004–2015, 2008. © 2007 Wiley‐Liss, Inc.
Inhibition of apoptosis in human laryngeal cancer cells by E6 and E7 oncoproteins of human papillomavirus 16
Authors: Liu Han Ching , Chen George G. , Vlantis Alexander C. , Tse Gary M. , Chan Anthony T.C. , van Hasselt C. Andrew
Published: July 2007

The carcinogenesis of human papillomaviruses type 16 (HPV‐16) is mainly due to its two oncoproteins, E6 and E7. Their carcinogenic features in term of their relationship with Bcl‐2 family are still unclear. We thus aimed to analyze the expression of Bcl‐2 family members, Bcl‐2, Bax, and Bak in laryngeal cancer cells transfected with the E6 or E7 and to determine the sensitivity of these cells to apoptotic stimuli. We employed two human laryngeal cancer cell lines, UMSCC12 and UMSCC11A in this study. These two cell lines were stably transfected with HPV16 E6, E7 or empty vector, pcDNA3.1. We found that E6 and E7 inhibited apoptosis induced by TNF‐α/CHX in both UMSCC11A and UMSCC12 cells, enhanced the stability of Bcl‐2 protein and increased the degradation of Bak protein. Furthermore, it was found that HPV‐16 E7 statistically enhanced the expression of Bcl‐2 in laryngeal cancer. The alteration of Bak by E6 and E7 was not through the influence on the Bak promoter, as the luciferase assay showed that neither E6 nor E7 changed the Bak promoter activity. We conclude that the evasion of apoptosis mediated by HPV‐16 E6 and E7 is associated with increased Bcl‐2 and decreased Bak in laryngeal carcinogenesis and that the decreased level of Bak by E6 and E7 is not caused by the regulation of the Bak promoter but by reducing its protein stability. J. Cell. Biochem. 103: 1125–1143, 2008. © 2007 Wiley‐Liss, Inc.
Targeting cell signaling pathways for drug discovery: An old lock needs a new key
Authors: Aggarwal Bharat B. , Sethi Gautam , Baladandayuthapani Veera , Krishnan Sunil , Shishodia Shishir
Published: July 2007

In this age of targeted therapy, the failure of most current drug‐discovery efforts to yield safe, effective, and inexpensive drugs has generated widespread concern. Successful drug development has been stymied by a general focus on target selection rather than clinical safety and efficacy. The very process of validating the targets themselves is inefficient and in many cases leads to drugs having poor efficacy and undesirable side effects. Indeed, some rationally designed drugs (e.g., inhibitors of receptor tyrosine kinases, tumor necrosis factor (TNF), cyclooxygenase‐2 (COX‐2), vascular endothelial growth factor (VEGF), bcr‐abl, and proteasomes) are ineffective against cancers and other inflammatory conditions and produce serious side effects. Since any given cancer carries mutations in an estimated 300 genes, this raises an important question about how effective these targeted therapies can ever be against cancer. Thus, it has become necessary to rethink drug development strategies. This review analyzes the shortcomings of rationally designed target‐specific drugs against cancer cell signaling pathways and evaluates the available options for future drug development. J. Cell. Biochem. 102: 580–592, 2007. © 2007 Wiley‐Liss, Inc.
Red mold rice ameliorates impairment of memory and learning ability in intracerebroventricular amyloid β‐infused rat by repressing amyloid β accumulation
Authors: Lee Chun‐Lin , Kuo Tzong‐Fu , Wang Jyh‐Jye , Pan Tzu‐Ming
Published: July 2007

Amyloid β (Aβ) peptide related to the onset of Alzheimer's disease (AD) damaged neurons and further resulted in dementia. Monascus‐fermented red mold rice (RMR), a traditional Chinese medicine as well as health food, includes monacolins (with the same function as statins) and multifunctional metabolites. In this study, ethanol extract of RMR (RE) was used to evaluate neuroprotection against Aβ40 neurotoxicity in PC12 cells. Furthermore, the effects of dietary administration of RMR on memory and learning abilities are confirmed in an animal model of AD rats infused with Aβ40 into the cerebral ventricle. During continuous Aβ40 infusion for 28 days, the rats of test groups were administered RMR or lovastatin. Memory and learning abilities were evaluated in the water maze and passive avoidance tasks. After sacrifice, cerebral cortex and hippocampus were collected for the examination of AD risk factors. The in vitro results clearly indicate that RE provides stronger neuroprotection in rescuing cell viability as well as repressing inflammatory response and oxidative stress. RMR administration potently reverses the memory deficit in the memory task. Aβ40 infusion increases acetylcholinesterase activity, reactive oxygen species, and lipid peroxidation and decreases total antioxidant status and superoxide dismutase activity in brain, but these damages were potently reversed by RMR administration, and the protection was more significant than that with lovastatin administration. The protection provided by RMR is able to prevent Aβ fibrils from being formed and deposited in hippocampus and further decrease Aβ40 accumulation, even though Aβ40 solution was infused into brain continuously. © 2007 Wiley‐Liss, Inc.
Peroxiredoxin 2 overexpression protects cortical neuronal cultures from ischemic and oxidative injury but not glutamate excitotoxicity, whereas Cu/Zn superoxide dismutase 1 overexpression protects only against oxidative injury
Authors: Boulos Sherif , Meloni Bruno P. , Arthur Peter G. , Bojarski Christina , Knuckey Neville W.
Published: July 2007

We previously reported that peroxiredoxin 2 (PRDX2) and Cu/Zn superoxide dismutase 1 (SOD1) proteins are up‐regulated in rat primary neuronal cultures following erythropoietin (EPO) preconditioning. In the present study, we have demonstrated that adenovirally mediated overexpression of PRDX2 in cortical neuronal cultures can protect neurons from in vitro ischemia (oxygen‐glucose deprivation) and an oxidative insult (cumene hydroperoxide) but not glutamate excitotoxicity. We have also demonstrated that adenovirally mediated overexpression of SOD1 in cortical neuronal cultures protected neurons only against the oxidative insult. Interestingly, we did not detect up‐regulation of PRDX2 or SOD1 protein in the rat hippocampus following exposure to either 3 min or 8 min of global cerebral ischemia. Further characterization of PRDX2's neuroprotective mechanisms may aid in the development of a neuroprotective therapy. © 2007 Wiley‐Liss, Inc.
Divalent metal transporter 1 up‐regulation is involved in the 6‐hydroxydopamine‐induced ferrous iron influx
Authors: Song Ning , Jiang Hong , Wang Jun , Xie Jun‐Xia
Published: July 2007

The reasons underlying the high iron content found in the substantia nigra (SN) of Parkinson's disease (PD) are largely unknown. We suppose, based on our previous studies, that the newly discovered iron transporter divalent metal transporter 1 (DMT1) might be involved in this SN iron accumulation process. To investigate this, we first observed the cellular expression of DMT1 in rat SN, both with the iron response element (+IRE) and without the IRE (−IRE) forms. The results showed that both forms of DMT1 were expressed on neurons, astrocytes, and microglia but not on oligodendrocytes. We further observed the relationship between the increased iron influx and DMT1 expression in 6‐hydroxydopamine (6‐OHDA)‐treated C6 cells. 6‐OHDA (10 μmol/liter) caused a significant increase in ferrous iron influx, with the increased expression of DMT1+IRE, both in protein and in mRNA levels, whereas no change was observed for DMT1−IRE. To clarify further that the increased expression of DMT1 was not due to the increased intracellular iron content, C6 cells were overloaded with ferric ammonium citrate (100 μg/ml). Decreased expression of both forms of DMT1 was observed. Our data suggest that DMT1 is highly expressed in rat SN in a cell‐specific manner. Increased DMT1+IRE expression is the mechanism behind ferrous iron influx induced by 6‐OHDA treatment in C6 cells. This may give some evidence for the involvement of DMT1 in the iron accumulation in PD. © 2007 Wiley‐Liss, Inc.
Current and future sources of raw materials for the long‐chain omega‐3 fatty acid market
Authors: Bimbo Anthony P.
Published: July 2007

Much is being written in the popular and scientific press about the impending shortage of fish oil in its key markets. While most of the concerns are aimed at the aquaculture industry where fish oil and fishmeal are highly desired products, questions have also been raised from groups within the nutritional oils and nutraceutical industry. The concerns have been fueled by ominous predictions of impending doom because ocean fish are being pursued to extinction. While the questions related to aquaculture have and continue to receive responses (1, 2, 3), the issue of raw materials for the long‐chain ω‐3, nutritional oils or nutraceutical market has not been specifically addressed. This paper attempts to put the ω‐3 fish oil situation regarding the nutritional oils industry into perspective.
Corrosion monitoring in a straw‐fired power plant using an electrochemical noise probe
Authors: Cappeln F. , Bjerrum N.J. , Petrushina I.M.
Published: July 2007

Electrochemical Noise Measurements have been carried out in situ in a straw‐fired power plant using an experimental probe constructed from alumina and AISI 347 steel. Based on a framework of controlled laboratory experiments it has been found that electrochemical noise has the unique ability to provide in‐situ monitoring of intergranular corrosion in progress. The probe had a lifetime of two months. It was shown that down‐time corrosion in the boiler was negligible. Electrochemical noise data indicated that metal temperatures around 590°C should be avoided as the intergranular corrosion is at an increased level at this temperature, most likely because of favorable conditions for molten salt film condensation.
Polyamine compound as a volatile corrosion inhibitor for atmospheric corrosion of mild steel*
Authors: Zhang D.‐Q. , Gao L.‐X. , Zhou G.‐D.
Published: July 2007

Bis‐piperidiniummethyl‐urea (BPMU) was developed as a volatile corrosion inhibitor (VCI) for mild steel. Its vapor corrosion inhibition property was evaluated by volatile inhibiting sieve test (VIS). Electrochemical measurements were conducted in simulated atmospheric corrosion water. Electrochemical impedance spectroscopy of a volatile corrosion inhibitor monitor cell (VCIM) was applied to study the effect of BPMU on the corrosion inhibition of mild steel under a thin electrolyte layer. The results show that BPMU has good protection effect for steel. It suppressed the anodic reaction of the steel electrode in a manner of promoted passivation. Fourier transform infrared (FT‐IR) spectroscopy was used to characterize the adsorption of BPMU on the steel surface.
Influence of intermittent loading on SCC behavior for an X70 pipeline steel in a near neutral pH solution
Authors: Wang Z. , Wang J. , Han E. , Ke W.
Published: July 2007

The influence of intermittent loading on stress corrosion cracking (SCC) behavior for an X70 pipeline steel was studied using slow strain rate tests (SSRT) in a near neutral pH soil solution at various applied potentials. The d.c. potential drop method was used to measure the crack initiation and propagation. The crack length at the cross section of the fractured sample was observed using scanning electron microscopy (SEM). The results showed that the crack initiation stress in solution was lower than the yield stress in air. SEM observation showed that the crack length was longer in intermittent loading than that in continuous loading. At anodic potential, the crack initiation stress was the lowest and the crack length was the longest. The crack kept growing during constant loading period.
Elasticity of Single Poly(amido amine) Dendrimers
Authors: Tomczak Nikodem , Vancso G. Julius
Published: July 2007

An atomic force microscope in the compression mode was used to probe the nanomechanical response of single dendrimeric molecules, as well as dendrimer aggregates adsorbed on silicon surface. The force‐compression behaviour of individual, generation 5 poly(amido amine) (PAMAM) dendrimers was described by a Hertzian model for the deformation of elastic bodies. The modulus values obtained ranged between 700 MPa (single dendrimers) and 150 MPa (dendrimer aggregates).

magnified image
Temperature Dependence of Creep Behavior of PP–MWNT Nanocomposites
Authors: Ganß Martin , Satapathy Bhabani K. , Thunga Mahendra , Weidisch Roland , Pötschke Petra , Janke Andreas
Published: July 2007

The creep behavior of poly(propylene)–multi‐walled carbon nanotube (MWNT) composites has been studied with short term tensile creep tests at different temperatures and is discussed in relation to the structural characteristics determined by AFM, DSC, and polarized light microscopy. Master curves of creep compliance have been constructed using a time–temperature superposition (TTS) concept based on the William–Landel–Ferry (WLF) equation. The nanocomposites have shown an increase in creep compliance with increasing temperature as a consequence of temperature‐activated motion of the polymer chains. This is critically discussed in the light of activation enthalpy and other influencing factors such as polymer–nanotube interaction and thermal expansion coefficients following semi‐empirical approximations.

magnified image
Surface Morphological Evolution of Ultrathin P4VP Films and Generation of Ordered Patterns on Graphite
Authors: Chen Dongzhong , Handa Hitesh , Wan Lei , Mao Guangzhao
Published: July 2007

The spin‐coated thin‐film morphology of poly(4‐vinylpyridine) has been studied by AFM; the dark lines or disks (circular holes) in the AFM height images correspond to the depressed regions. An epitaxy‐like “nano‐trench” pattern was observed in the noncrystalline polymer film deposited on the crystalline graphite substrate. The transition from surface‐templated to isotropic dewetting occurs during 3 nm of the film thickness increase. This study presents an example of ordered nanopatterns emerging from the chaotic spin‐coating process. The well‐defined “nano‐trench” morphology offers an opportunity for the study of the nanoconfinement effect and provides a unique means for surface patterning and nanolithography.

magnified image
A finite element modified method of characteristics for convective heat transport
Authors: El‐Amrani Mofdi , Seaïd Mohammed
Published: July 2007

We propose a finite element modified method of characteristics for numerical solution of convective heat transport. The flow equations are the incompressible Navier‐Stokes equations including density variation through the Boussinesq approximation. The solution procedure consists of combining an essentially non‐oscillatory modified method of characteristics for time discretization with finite element method for space discretization. These numerical techniques associate the geometrical flexibility of the finite elements with the ability offered by modified method of characteristics to solve convection‐dominated flows using time steps larger than its Eulerian counterparts. Numerical results are shown for natural convection in a squared cavity and heat transport in the strait of Gibraltar. Performance and accuracy of the method are compared to other published data. © 2007 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2008
Convergence analysis of an approximation to miscible fluid flows in porous media by combining mixed finite element and finite volume methods
Authors: Amaziane Brahim , El Ossmani Mustapha
Published: July 2007

This article deals with development and analysis of a numerical method for a coupled system describing miscible displacement of one incompressible fluid by another through heterogeneous porous media. A mixed finite element (MFE) method is employed to discretize the Darcy flow equation combined with a conservative finite volume (FV) method on unstructured grids for the concentration equation. It is shown that the FV scheme satisfies a discrete maximum principle. We derive L∞ and BV estimates under an appropriate CFL condition. Then we prove convergence of the approximate solutions to a weak solution of the coupled system. Numerical results are presented to see the performance of the method in two space dimensions. © 2007 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2008
FGFR3 protein expression and its relationship to mutation status and prognostic variables in bladder cancer
Authors: Tomlinson DC , Baldo O , Harnden P , Knowles MA
Published: July 2007

FGFR3 is frequently activated by mutation in urothelial carcinoma (UC) and represents a potential target for therapy. In multiple myeloma, both over‐expression and mutation of FGFR3 contribute to tumour development. To define the population of UC patients who may benefit from FGFR‐targeted therapy, we assessed both mutation and receptor over‐expression in primary UCs from a population of new patients. Manual or laser capture microdissection was used to isolate pure tumour cell populations. Where present, non‐invasive and invasive components in the same section were microdissected. A screen of the region of the highest tumour stage in each sample yielded a mutation frequency of 42%. Mutations comprised 61 single and five double mutations, all in hotspot codons previously identified in UC. There was a significant association of mutation with low tumour grade and stage. Subsequently, non‐invasive areas from the 43 tumours with both non‐invasive and invasive components were analysed separately; 18 of these had mutation in at least one region, including nine with mutation in all regions examined, eight with mutation in only the non‐invasive component and one with different mutations in different regions. Of the eight with mutation in only the non‐invasive component, six were predicted to represent a single tumour and two showed morphological dissimilarity of fragments within the block, indicating the possible presence of distinct tumour clones. Immunohistochemistry showed over‐expression of FGFR3 protein in many tumours compared to normal bladder and ureteric controls. Increased expression was associated with mutation (85% of mutant tumours showed high‐level expression). Overall, 42% of tumours with no detectable mutation showed over‐expression, including many muscle‐invasive tumours. This may represent a non‐mutant subset of tumours in which FGFR3 signalling contributes to the transformed phenotype and which may benefit from FGFR‐targeted therapies. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
T and B lymphocyte depletion has a marked effect on the fibrosis of dystrophic skeletal muscles in the scid/mdx mouse
Authors: Farini A , Meregalli M , Belicchi M , Battistelli M , Parolini D , D'Antona G , Gavina M , Ottoboni L , Constantin G , Bottinelli R , Torrente Y
Published: July 2007

Abnormal connective tissue proliferation following muscle degeneration is a major pathological feature of Duchenne muscular dystrophy (DMD), a genetic myopathy due to lack of the sarcolemmal dystrophin protein. Since this fibrotic proliferation is likely to be a major obstacle to the efficacy of future therapies, research is needed to understand and prevent the fibrotic process in order to develop an effective treatment. Murine muscular dystrophy (mdx) is genetically homologous to DMD, and histopatological alterations are comparable to those of the muscles of patients with DMD. To investigate the development of fibrosis, we bred the mdx mouse with the scid immunodepressed mouse and analysed fibrosis histologically; we used ELISA analysis to determine TGF‐β1 expression. Significant reduction of fibrosis and TGF‐β1 expression was found in the muscles of the scid/mdx mice. However, we observed similar centrally located nuclei, necrosis, muscle degeneration and muscle force compared to the mdx animals. These data demonstrate a correlation between the absence of B and T lymphocytes and loss of fibrosis accompanied by reduction of TGF‐β1, suggesting the importance of modulation of the immune system in DMD. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Poly(methyl methacrylate) Films Deposited via Non‐Equilibrium Atmospheric Pressure Plasma Polymerization Using Argon as Working Gas
Authors: Kasih Tota Pirdo , Kuroda Shin‐ichi , Kubota Hitoshi
Published: July 2007

A non‐equilibrium atmospheric pressure plasma torch using argon (Ar) for sustaining plasma has been developed, and it was used to deposit plasma polymerized methyl methacrylate (PPMMA) films. The chemical structure and composition of the films obtained were examined by FT‐IR and XPS analyses. It was found that, when raising the concentration of vaporized monomer to a certain level into the plasma, the plasma transitioned from a filamentary to a glow‐like discharge, this resulting in a high retention of the monomer structure. Since the optical emission spectroscopy (OES) study of the plasma did not show any new excited species formed at higher concentrations of the monomer, it is clear that the fragmentation degree of the monomer in the plasma phase was quite low.

magnified image
Coherent state path integral and super‐symmetry for condensates composed of bosonic and fermionic atoms
Authors: Mieck B.
Published: July 2007

A super‐symmetric coherent state path integral on the Keldysh time contour is considered for bosonic and fermionic atoms which interact among each other with a common short‐ranged two‐body potential. We investigate the symmetries of Bose‐Einstein condensation for the equivalent bosonic and fermionic constituents with the same interaction potential so that a super‐symmetry results between the bosonic and fermionic components of super‐fields. Apart from the super‐unitary invarianceU(L|S) of the density terms, we specialize on the examination of super‐symmetries for pair condensate terms. Effective equations are derived for anomalous terms which are related to the molecular‐ and BCS‐ condensate pairs. A Hubbard‐Stratonovich transformation from ‘Nambu’‐doubled super‐fields leads to a generating function with super‐matrices for the self‐energy whose manifold is given by the orthosympletic super‐groupOsp(S,S| 2L). A nonlinear sigma model follows from the spontaneous breaking of the ortho‐symplectic super‐groupOsp(S,S| 2L) to the coset decompositionOsp(S,S| 2L) \U(L|S)⊗U(L|S). The invariant subgroupU(L|S) for the vacuum or background fields is represented by the density terms in the self‐energy whereas the super‐matrices on the coset spaceOsp(S,S| 2L) \U(L|S) describe the anomalous molecular and BCS‐ pair condensate terms. A change of integration measure is performed for the coset decompositionOsp(S,S| 2L) \U(L|S) ⊗U(L|S), including a separation of density and anomalous parts of the self‐energy with a gradient expansion for the Goldstone modes. The independent anomalous fields in the actions can be transformed by the inverse square root$\hat{G}_{Osp\backslash U}^{-1/2}$of the metric tensor ofOsp(S,S| 2L) \U(L|S) so that the non‐Euclidean integration measure with super‐Jacobi‐determinant$[{\rm SDET} (\hat{G}_{Osp\backslash U})]^{1/2}$can be removed from the coherent state path integral and Gaussian‐like integrations remain. The variations of the independent coset fields in the effective actions result in classical field equations for a nonlinear sigma model with the anomalous terms. The dynamics of the eigenvalues of the coset matrices is determined by Sine‐Gordon equations which have a similar meaning for the dynamics of the molecular‐ and BCS‐pair condensates as the Gross‐Pitaevskii equation for the coherent wave function in BEC phenomena.
Thermal evolution of small N–D complexes in deuterated dilute nitrides revealed by in‐situ high resolution X‐ray diffraction
Authors: Bisognin G. , De Salvador D. , Napolitani E. , Berti M. , Polimeni A. , Felici M. , Capizzi M. , Bais G. , Jabeen F. , Piccin M. , Rubini S. , Martelli F. , Franciosi A.
Published: July 2007

In this article we studied the thermal evolution of nitrogen–deuterium (N–D) complexes which form in dilute nitride GaAs1–x Nx alloys as a consequence of D irradiation. These complexes are particularly important and interesting because they lead to the electronic passivation of N and also because their formation is accompanied by a strain reversal (from tensile to compressive) of the as‐grown material. By collecting in‐situ high resolution X‐ray diffraction rocking‐curves during thermal annealing, we were able to monitor in real time the evolution of the lattice parameter (a) of the samples, demonstrating that two processes are involved in the dissolution of N–D clusters. During the first process a evolves from values larger than that of the GaAs substrate saturating at values very close to the GaAs one, while the second process, that starts at a higher temperature, leads to an almost complete recovery of the D‐free GaAs1–x Nx lattice parameter. By analizing the thermal evolution of a, we were able to extract information about the energetics of the two N–D complexes dissolution steps. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Determination of stacking fault densities in 3C‐SiC crystals by diffuse X‐ray scattering
Authors: Boulle A. , Chaussende D. , Pecqueux F. , Conchon F. , Latu‐Romain L. , Masson O.
Published: July 2007

Thick 3C‐SiC single crystals grown by continuous‐feed physical vapor transport (CF‐PVT) are studied by high‐resolution X‐ray reciprocal space mapping. These crystals contain Shockley‐type stacking faults (SFs) lying in the {111} planes, which give rise to diffuse intensity streaks along the 〈111〉 directions. An approach is presented that allows to determine, in combination with the simulation of transverse scans, the SF density from the simulation of the diffuse intensity streaks. SF densities as low as 0.4 × 103 cm–1 could be detected in high‐quality CF‐PVT grown crystals. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Investigation by High Resolution X‐ray Diffraction of the local strains induced in Si by periodic arrays of oxide filled trenches
Authors: Eberlein M. , Escoubas S. , Gailhanou M. , Thomas O. , Micha J.‐S. , Rohr P. , Coppard R.
Published: July 2007

High Resolution X‐ray Diffraction allows for the measurement of periodic strain fields in monocrystalline silicon and is non‐destructive. In this study a periodic strain field is induced in Si by SiO2 filled trenches (Shallow Trench Isolation process). The strain in Si is evaluated for different periods of the trench arrays namely from 2 μm to 0.2 μm. The periodic strain field gives rise to satellites in reciprocal space maps around the Si substrate peak. The intensity and envelope of these satellites depend on the local strain. The experimental reciprocal space maps are qualitatively compared with those computed from the elastic displacement field calculated with finite element modeling. When the array period decreases, a strong increase in local strain is observed. From 0.58 μm period and below, in addition to the Si substrate diffraction peak, a secondary diffraction peak representative of the strain in Si lines can be distinguished on reciprocal space maps. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
X‐ray diffraction peaks from misfit dislocations in double‐ and triple‐crystal diffractometry
Authors: Kaganer Vladimir M. , Shalimov Artem , Bak‐Misiuk Jadwiga , Ploog Klaus H.
Published: July 2007

We propose a common description of the full widths at half maximum of X‐ray diffraction peaks obtained in different scans of triple‐crystal diffractometry and as well as for glancing incidence and glancing exit double‐crystal measurements. Calculations are compared with measurements of GaAs/Si(001) heteroepitaxial films. We show that the diffraction peak broadening is entirely due to random 60° misfit dislocations that provide only a minor part of the misfit relaxation. The remaining relaxation is due to periodic edge misfit dislocations that do not contribute to the peak broadening. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Anomalous scattering and isomorphous replacement in X‐ray diffuse scattering holography
Authors: Kopecký Miloš , Kub Jiří , Busetto Edoardo , Lausi Andrea , Fábry Jan , Šourek Zbyněk
Published: July 2007

Two concepts of X‐ray diffuse scattering holography resulting in local atomic structure are presented. The first one uses the anomalous scattering near the absorption edge of a selected element. The second one is based on the variation of atomic scattering factor due to the isomorphous replacement of a selected atom in the structure by another one with different scattering properties. Feasibility of both concepts was demonstrated experimentally on a RbCl single crystal and GaMnAs epitaxial layer. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Wide angle X‐ray dynamical diffraction by deformed crystals: recurrence relations
Authors: Pavlov K. M. , Paganin D. M. , Vine D. J. , Kirste L.
Published: July 2007

Dynamical wide‐angle multiwave X‐ray diffraction from a deformed crystal was considered, for the special case when no more than one strong reflection occurs at a time. The obtained set of equations can be transformed to the Takagi two‐beam approximation if the scattering vector is close to a vector of the reciprocal lattice. The new formalism was employed to obtain recurrence relations for the amplitude reflection coefficient corresponding to laterally homogeneous multilayer structures for the case of coplanar Bragg diffraction. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Pyroelectric‐piezoelectric related enhancement of the domain contrast on topographs performed using a coherent X‐ray beam in LiNbO3 at low temperature
Authors: Pernot Petra , Baruchel José
Published: July 2007

Low‐temperature experiments (20–300 K) on a periodically poled lithium niobate using white‐beam section topography with a highly coherent X‐ray beam show a dramatic increase of the periodic contrast. This contrast produces as periodic black lines, with the period of the domains, and it occurs even for short sample‐to‐detector distances (10 cm). This behaviour suggests a new origin of the contrast, which adds to the room temperature one associated with the phase difference between the structure factors of inverted domains. We propose an explanation of the observed phenomenon at low temperatures, based on additional phase contrast between adjacent domains appearing due to their misorientation via the lattice parameter a modification that produces through the inverse piezoelectric effect. This effect results from the constant sign of the internal electric field present in the sample, and the sign variation, from one domain to the other, of the generated pyroelectric response, which increases substantially below 180 K. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Real‐time X‐ray reflectometry during thin‐film processing
Authors: Peverini L. , Kozhevnikov I. , Ziegler E.
Published: July 2007

An apparatus and a characterization technique have been developed at the ESRF beamline BM5 to investigate in‐situ the evolution of the morphology of a film using grazing incidence X‐ray reflectometry. The instrument is capable of measuring in‐situ and in real time the X‐ray intensity specularly and diffusely scattered from a rough thin film during various surfacing processes. The variation of the specular intensity as a function of the processing time, recorded simultaneously with each X‐ray scattering diagram, is analyzed to infer the film growth rate, the film density and the variation of roughness conformity during surface processing.

The potential of the method is demonstrated for two particular cases: thin film deposition by magnetron sputtering and subsequent film etching by low energy ion bombardment. The paper describes some recent achievements and present examples of on‐line diagnostics for which real time in‐situ X‐rays reflectometry proves to be a unique probe. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Real‐time and in situ solidification of Al‐based alloys investigated by synchrotron radiation: a unique experimental set‐up combining radiography and topography techniques
Authors: Buffet A. , Reinhart G. , Schenk T. , Nguyen‐Thi H. , Gastaldi J. , Mangelinck‐Noël N. , Jung H. , Härtwig J. , Baruchel J. , Billia B.
Published: July 2007

A unique experimental set‐up combining X‐ray radiography and topography has been recently developed at the ESRF. It allows direct observation of the solidification microstructure by these two complementary imaging techniques. This combined observation offers new possibilities, in particular for the investigation of strains, stresses and defect formation during directional solidification. In this paper we present in detail the experimental device and selected results obtained for two Al‐based alloys: Al–3.5 wt% Ni and β‐Al3Mg2. For the first time, we were able to characterize and quantify (by using topography) mechanical phenomena observed by radiography during the growth process. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Synchrotron X‐ray Renninger scanning for studying strain in InAs/GaAs quantum dot system
Authors: Freitas Raul O. , Lamas Tomás E. , Quivy Andre A. , Morelhão Sérgio L.
Published: July 2007

A systematic procedure for ultra‐precise lattice parameter determination using X‐ray Renninger scanning (XRS) is optimized and applied to probe the average in‐plane strain in series of samples representing the different stages of the growth process of single‐buried quantum dots (QDs). Covering InAs QDs growth on GaAs(001) substrates generates an expansive in‐plane strain that is related to the density of QDs. Rocking curves and atomic force microscopy are also used for a general qualitative analysis of the growths, as well as of the morphology and density of the QDs. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Analyzer‐based X‐ray phase contrast imaging with four bounce Si(444) monochromators at ELETTRA
Authors: Hönnicke M. G. , Rigon L. , Arfelli F. , Menk R.‐H. , Cusatis C.
Published: July 2007

An analyzer‐based X‐ray phase contrast imaging setup (ABI) based on four bounce Si(444) monochromators at 18 keV mounted at the SYRMEP beamline at Elettra is presented. The system was stable for the employed exposure times. Contrasts, visibility of the object edges and signal to noise ratio of the acquired images were studied. Simulation procedures of the images were also exploited. The results show that such setup can be used for high sensitivity (high contrast) experiments at Elettra. Also, due to intrinsic properties, this setup can be useful for future ultra‐small angle X‐ray scattering experiments. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Structural anisotropy of InGaAs/GaAs(001) quantum dot chains structures
Authors: Kladko V. P. , Slobodian M. V. , Strelchuk V. V. , Yefanov O. M. , Machulin V. F. , Mazur Yu. I. , Wang Zh. M. , Salamo G. J.
Published: July 2007

We have studied the structural properties of ordered InGaAs/GaAs(001) quantum dot chains multilayer by high‐resolution X‐ray diffraction. Two systems of lateral satellites, one of which being inclined with respect to the sample surface normal, i.e. the growth direction [001], were observed. The measured inclination of 30.0° ± 2.5° does not affect the diffraction profile from planar superlattice (SL), i.e. SL peaks are not inclined with respect to the GaAs substrate peak. We identify the splitting of coherent SL satellites for all orders as well as for two perpendicular directions. This splitting most likely indicates that two discrete periods exist in SL structure. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Characterization of dislocations in orthorhombic hen egg‐white lysozyme crystals by synchrotron X‐ray topography
Authors: Koizumi H. , Shimizu M. , Tachibana M. , Kojima K.
Published: July 2007

Orthorhombic hen egg‐white (HEW) lysozyme crystals were examined by means of synchrotron X‐ray topography by the white beam technique. Four kinds of straight dislocations were clearly observed. From the extinction criterion of the dislocation images, Burgers vectors were identified to be [001], [$ \bar 1 $10] and [0$ \bar 1 $1]. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Evolution of the microdefect structure in silicon on isothermal annealing as determined by X‐ray diffractometry
Authors: Kyslovskyy Ye. M. , Vladimirova T. P. , Olikhovskii S. I. , Molodkin V. B. , Kochelab E. V. , Seredenko R. F.
Published: July 2007

The dynamical theory of X‐ray diffraction by imperfect crystals with randomly distributed microdefects, applicable to double‐crystal diffractometry (DCD), has been extended to account for the simultaneous presence of several types of microdefects. The obtained formulae for coherent and diffuse components of the rocking curve (RC) have been applied to the quantitative characterization of the complex microdefect structure in silicon samples annealed at 750 °C for various time intervals by using high‐resolution double‐crystal X‐ray diffraction measurements. Time dependencies of concentrations and average sizes of oxygen precipitates and dislocation loops have been determined by using characterization results. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Interface stability of magnetic tunnel barriers and electrodes
Authors: Lamperti A. , Pym A. T. G. , Eastwood D. S. , Cardoso S. , Wisniowski P. , Freitas P. P. , Anderson G. I. R. , Marrows C. H. , Tanner B. K.
Published: July 2007

Grazing incidence X‐ray scattering during in‐situ annealing has been used to study the interface stability in MgO‐based electrodes and barriers in magnetic tunnel junctions (MTJs). In MTJs based on Co60Fe20B20/MgO, low temperature annealing at about 200 °C can result in a drop in the tunnelling magnetoresistance (TMR). Specular reflectivity measurements show a change in fringe structure at high scattering vector, at the temperature at which the TMR drops. Also, a change in diffuse scatter relative to the specular scatter is observed. Annealing of [Co60Fe60B20/MgO]×14 multilayers prepared by three different techniques shows no change in the specular Bragg peaks with no loss of Kiessig fringe structure on crystallization and no change in the diffuse scatter up to 200 °C. We suggest that diffusion of Mn from the IrMn pinning layer, present in the MTJs but not in the multilayers, may be responsible for the differences in TMR behaviour. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
High resolution X‐ray diffraction analyses of ion‐implanted GaN/AlN/Si heterostructures
Authors: Matyi R. J. , Jamil M. , Shahedipour‐Sandvik F.
Published: July 2007

High resolution triple‐axis X‐ray diffraction has been used to characterize the effects of nitrogen ion implantation into thin (15 nm and 55 nm) AlN buffer layers on the resultant structural quality of nominally 2 μm epitaxial GaN layers grown on silicon substrates. The GaN symmetric (0002) and the asymmetric (10$ \bar 1 $4) and (10$ \bar 1 $5) Bragg reflections shows that in all cases, the extent of the off‐peak kinematic diffuse scattering was reduced when growth was performed on the ion‐implanted AlN buffer layers. Analysis of the log I – log q dependence of the kinematic intensity shows linear behavior but with slopes changing from –4.3 to –3.7 (in the case of the (0002) reflection) in the unimplanted and ion‐implanted buffer layers, respectively, indicating a change in the defect character in the layers. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)