bluuebunny/crossref_metadata_2025 huggingface dataset:
Proinsulin C‐peptide abrogates type‐1 diabetes‐induced increase of renal endothelial nitric oxide synthase in rats
Authors: Kamikawa Akihiro , Ishii Tatsuya , Shimada Kohei , Makondo Kennedy , Inanami Osamu , Sakane Naoki , Yoshida Toshihide , Saito Masayuki , Kimura Kazuhiro
Published: December 2007

Background

Proinsulin C‐peptide shows ameliorative effects on diabetic complications, possibly through the production of nitric oxide (NO). On the contrary, increased local availability of NO and expression of endothelial NO synthase (eNOS) in the renal endothelium are shown to be involved in the progression of diabetic nephropathy. The aim of this study was to elucidate the effect of C‐peptide and insulin as a reference on the eNOS expression in the early phase of type 1 diabetic rat kidney.

Methods

Type 1 diabetes in rats was produced by streptozotocin injection and some of the rats were treated with either C‐peptide or insulin by the aid of an osmotic pump for 1 week. Conventional biochemical and histological analyses were performed on tissue samples.

Results

The diabetic rats showed hyperglycemia with over 90% reduction of endogenous insulin and C‐peptide. Replacement with C‐peptide or insulin resulted in recovery of weight lost, but only insulin infusion lowered plasma‐glucose concentration. The eNOS protein was localized in glomeruli and endothelial cells of arterioles, and its amounts in the kidneys, but not in the lungs, of diabetic rats was increased. Replacement with C‐peptide or insulin‐abrogated diabetes‐induced increase of renal eNOS protein.

Conclusion

The results indicate that C‐peptide suppresses diabetes‐induced abnormal renal eNOS expression, by which C‐peptide may exert beneficial effects on diabetic nephropathy. Copyright © 2007 John Wiley & Sons, Ltd.
Electronic Tongue Using an Enzyme Inhibition Biosensor Array for the Resolution of Pesticide Mixtures
Authors: Cortina Montserrat , del Valle Manuel , Marty Jean‐Louis
Published: December 2007

An electronic tongue has been developed, employing an array of inhibition biosensors and Artificial Neural Networks (ANNs). The array of biosensors was formed by three amperometric pesticide biosensors that used different acetylcholinesterase (AChE) enzymes: the wild type from electric eel (EE) and two different genetically modified enzymes (B1 and B394). In order to model the response to dichlorvos and carbofuran mixtures, a total amount of 22 solutions were prepared, with random concentrations. Chronoamperometric responses of the biosensor array were used in order to obtain the inhibition bioelectronic tongue. Mean values of concentration of pesticides evaluated were 0.79 nM for dichlorvos and 4.1 nM for carbofuran. Good prediction ability was obtained with correlation coefficients better than 0.918 when the obtained values were compared with those expected for a set of 6 external test samples not used for training.
Intersection of nuclear receptors and the proteasome on the epigenetic landscape
Authors: Kinyamu H. Karimi , Jefferson Wendy N. , Archer Trevor K.
Published: December 2007

Nuclear receptors (NRs) represent a class of transcription factors that associate with both positive and negative chromatin modifying complexes to activate or repress gene transcription. The 26S proteasome plays a major role in NR‐regulated gene transcription by tightly regulating the levels of the receptor and coregulator complexes. Recent evidence suggests a robust nonproteolytic role for specific proteasome subunits in gene transcription mediated via alterations in specific histone modifications. The involvement of nuclear receptors and the proteasome with chromatin modifying complexes or proteins, particularly those that modify DNA and histone proteins, provides an opportunity to review two critical epigenetic mechanisms that control gene expression and heritable biological processes. Both nuclear receptors and the proteasome are targets of environmental factors including some which lead to epigenetic changes that can influence human diseases such as cancer. In this review, we will explore molecular mechanisms by which NR‐mediated gene expression, under the control of the proteasome, can result in altered epigenetic landscapes. Environ. Mol. Mutagen., 2008. Published 2007 Wiley‐Liss, Inc.
Seismic self‐centering steel beam‐to‐column moment connections using bolted friction devices
Authors: Tsai Keh‐Chyuan , Chou Chung‐Che , Lin Chi‐Lon , Chen Pei‐Ching , Jhang Sheng‐Jhih
Published: December 2007

This paper first presents the force–deformation relationship of a post‐tensioned (PT) steel beam‐to‐column connection constructed with bolted web friction devices (FDs). This paper then describes the test program conducted in the National Center for Research on Earthquake Engineering, Taiwan, on four bolted FDs and four full‐scale PT beam‐to‐column moment connection subassemblies using the FDs. Tests confirm that (1) the hysteretic behavior of four bolted FDs is very stable, (2) the friction coefficient between the steel plate and the brass shim is about 0.34, (3) the proposed force–deformation relationships reasonably predict the experimental responses of the PT connections under cyclically increasing deformations up to a beam peak rotation of 0.05 rad, and (4) the decompression moments do not degrade as beam cyclic deformations increase. Copyright © 2007 John Wiley & Sons, Ltd.
Geological and archaeological chronology of a late Holocene coastal enclosure: The Sanguinet lake (SW France)
Authors: Tastet Jean‐Pierre , Lalanne René , Maurin Bernard , Dubos Bernard
Published: December 2007

Sanguinet lake is separated from the Atlantic Ocean by a wide Holocene coastal dunes system in SW France. The present day lake level is 21 m above mean sea level (msl). It formed when aeolian sand closed the mouth of the small La Gourgue river which gradually became a lagoon and then a lake. Dated sub‐lacustrine archaeological remains (human settlements, canoes, and wooden architectural structures), as well as paleoenvironmental evidence (drowned tree stumps and lagoonal deposits exposed on the beach) are used to interpret the formation and chronology of lake level rise during the past 4000 years.

Around 2000–1650 B.C., the river flowed into a lagoon or an estuary which connected with the ocean west of the present Sanguinet Lake. Its level was affected by the tide, which ranged between 2 m below and 3 m above msl. The accumulation of aeolian sand before 1500–1000 B.C. began to close the connection with the sea. At this time, the elevation of the surface of the lake water was approximately 5 m above msl, but it still remained connected to the ocean. Around 1000 B.C., the lake level rose quickly by 1 to 2 m during a period of renewed mobility of the coastal aeolian sand, and continued to rise slowly until about 100 A.D. when there was a gradual closure of the lake outlet. This rise forced people who were living on the lake shore and along the rivers to move to higher land along the valley. The nearby Gallo‐Roman site of Losa was settled at the end of the 1st century B.C.; then the final blocking of the outlet occurred because of spit growth as a result of north‐south littoral drift accompanied by the deposit of aeolian sand. This led to the lake level rising rapidly. Consequently, Losa was abandoned in the 3rd century A.D. and ruins of its temple (at 17 m above msl) were submerged in the 6th century. Further oscillations of the lake level probably correspond to water table fluctuations before it became stable at around 1000 A.D.

The highest lake level (23.35 m) was reached during the 18th century as a consequence of modern dune formation, and thus was artificially reduced to 21 m in 1840 by construction of an overflow channel. © 2008 Wiley Periodicals, Inc.
Production of oxalates In Vitro by Microbes Isolated from Rock Surfaces with prehistoric paints in the Lower Pecos Region, Texas
Authors: Hess Darren , Coker Dana Jo , Loutsch Jeannette M. , Russ Jon
Published: December 2007

Calcium oxalate‐rich rock coatings are ubiquitous on limestone inside dry rock shelters and under bluff overhangs along canyon walls in southwestern Texas. Prehistoric pictographs occur in more than 250 such sites, and the ancient paints are encapsulated within the natural rock coating. Previous studies suggest lichens were the source of the oxalate; however, we report here that microbes cultured and isolated from samples of the coating produce oxalate in vitro. Twenty different bacteria species have been identified in samples from eight different sites, with Bacillus the most common genus, represented by five species. HPLC analyses of inoculated R2B medium after eight months of bacterial growth revealed the presence of oxalate ions in the solid phase of the growth medium. © 2008 Wiley Periodicals, Inc.
The paleohydrological context of the Iron Age floodplain sites of the Mun River Valley, Northeast Thailand1
Authors: McGrath R. J. , Boyd W. E. , Bush R. T.
Published: December 2007

Many Iron Age sites on the flood plain of the Mun River in northeast Thailand are encircled by channels commonly known as “moats.” Also, the sites are closely associated with complex paleochannels of the river. A comparison between the seemingly human‐constructed moats and paleochannels provided an opportunity to assess the relationship between prehistoric human settlement and paleohydrological conditions. In this study, the results of physical, sedimentological, and geochemical analyses are used to characterize sediments deposited within the channels around the Iron Age site of Ban Non Wat and within a paleochannel at nearby Ban Non Ngiu. This allowed us to test the results of previous research that has suggested significant changes in the floodplain hydrology and the geoarchaeologically important conclusion that Iron Age human activity was associated with one particular paleohydrological phase. Our analyses broadly confirm the results of previous stratigraphic studies, but add detail regarding sedimentation processes. The evidence indicates that there are significant sedimentological differences within the complex of archaeological channel features, differences that provide critical evidence for the formation and sedimentation processes of the channels. More importantly, comparison between the archaeological features and the natural channel fills highlights the relationships between the archaeological sites and landscape. Drawing also on previously published chronological, geomorphological, and stratigraphical data, it is possible to place the sites into a floodplain hydrological regime that may have been unique to the Iron Age. Specifically, the moats may have been constructed in response to enhanced water availability on the floodplain. The sites, therefore, may reflect a human response to increased availability of water beyond the main river channels. This water supply, however, appears to have been short‐lived (centuries at most), and with its loss, the human adaptation to this enhanced natural resource became unviable. © 2008 Wiley Periodicals, Inc.
Effective connectivity of the left BA 44, BA 45, and inferior temporal gyrus during lexical and phonological decisions identified with DCM
Authors: Heim Stefan , Eickhoff Simon B. , Ischebeck Anja K. , Friederici Angela D. , Stephan Klaas E. , Amunts Katrin
Published: December 2007

Distinct regions in the left inferior frontal gyrus (IFG) preferentially support the processing of different word‐types (e.g., real words, pseudowords) and tasks (e.g., lexical decisions, phonological decisions) in visual word recognition. However, the functional connectivity underlying the task‐related specialisation of regions in the left IFG is not yet well understood. In this study we investigated the neural mechanisms driving the interaction of WORD‐TYPE (real word vs. pseudoword) and TASK (lexical vs. phonological decision) in Brodmann's area (BA) 45 in the left IFG using dynamic causal modelling (DCM). Four different models were compared, all of which included left BA44, left BA45, and left inferior temporal gyrus (ITG). In each model, the visual presentation of words and pseudowords is assumed to directly evoke activity in the ITG and is then thought to be subsequently propagated to BA45 and to BA44 via direct intrinsic connections. The models differed with regard to which connections were modulated by the different tasks. Both tasks were assumed to either modulate the ITG_BA45 connection (Model #1), or the BA44_BA45 connection (Model #2), or both connections in parallel (Model #3). In Model #4 lexical decisions modulated the ITG_BA45 connection, whereas phonological decisions modulated the BA44_BA45 connection. Bayesian model selection revealed a superiority of Model #1. In this model, the strength of the ITG_BA45 connection was enhanced during lexical decisions. This model is in line with the hypothesis that left BA 45 supports explicit lexical decisions during visual word recognition based on lexical access in the ITG. Hum Brain Mapp, 2009. © 2007 Wiley‐Liss, Inc.
Task‐relevance and temporal synchrony between tactile and visual stimuli modulates cortical activity and motor performance during sensory‐guided movement
Authors: Meehan Sean K. , Staines W. Richard
Published: December 2007

Sensory‐guided movements require the analysis and integration of task‐relevant sensory inputs from multiple modalities. This article sought to: (1) assess effects of intermodal temporal synchrony upon modulation of primary somatosensory cortex (S1) during continuous sensorimotor transformations, (2) identify cortical areas sensitive to temporal synchrony, and (3) provide further insight into the reduction of S1 activity during continuous vibrotactile tracking previously observed by our group (Meehan and Staines 2007: Brain Res 1138:148–158). Functional MRI was acquired while participants received simultaneous bimodal (visuospatial/vibrotactile) stimulation and continuously tracked random changes in one modality, by applying graded force to a force‐sensing resistor. Effects of intermodal synchrony were investigated, unbeknownst to the participants, by varying temporal synchrony so that sensorimotor transformations dictated by the distracter modality either conflicted (low synchrony) or supplemented (high synchrony) those of the target modality. Temporal synchrony differentially influenced tracking performance dependent upon tracking modality. Physiologically, synchrony did not influence S1 activation; however, the insula and superior temporal gyrus were influenced regardless of tracking modality. The left temporal‐parietal junction demonstrated increased activation during high synchrony specific to vibrotactile tracking. The superior parietal lobe and superior temporal gyrus demonstrated increased activation during low synchrony specific to visuospatial tracking. As previously reported, vibrotactile tracking resulted in decreased S1 activation relative to when it was task‐irrelevant. We conclude that while temporal synchrony is represented at higher levels than S1, interactions between inter‐ and intramodal mechanisms determines sensory processing at the level of S1. Hum Brain Mapp, 2009. © 2007 Wiley‐Liss, Inc.
The significances of lymph node micrometastasis and its correlation with E‐cadherin expression in pT1‐T3N0 gastric adenocarcinoma
Authors: Kim Jong‐Han , Park Joong‐Min , Jung Cheol‐Woong , Park Sung‐Soo , Kim Seung‐Joo , Mok Young‐Jae , Kim Chong‐Suk , Chae Yang‐Suk , Bae Jeoung‐Won
Published: December 2007

Background

Recently, micrometastasis (MM) in the lymph node in gastric cancer has been detected by cytokeratin immunostaining. However, clinical significance of MM and its relationship with reduced expression of E‐cadherin in primary lesion have not been well studied.

Methods

The 4,990 lymph nodes from 184 pT1∼T3N0 patients from 1995 to 2000 at Korea University Hospital were immunostained with the anticytokeratin AE1/3 antibody for detection of micometastasis. The primary lesions were also immunostained for E‐cadherin expression.

Results

MM in the lymph node of gastric cancer was found in 131 (2.6%) of total dissected nodes, and 31 of 184 patients (16.8%) were shown to have MM. The MM was significantly correlated with the depth of invasion, tumor size, operation method, Lauren classification, lymphovascular invasion and loss of E‐cadherin expression in primary tumor. On multivariate analysis, the independent risk factors for MM were the depth of invasion and loss of E‐cadherin expression. The patients with MM had significantly lower 5‐year overall and disease free survival rate than those without MM.

Conclusion

Lymph node MM in histologically node‐negative gastric cancer was significantly correlated with poor 5‐year survival rate. The determination of E‐cadherin expression in primary gastric tumor may be useful in prediction of the MM. J. Surg. Oncol. 2008;97:125–130. © 2007 Wiley‐Liss, Inc.
Tumor size: A non‐neglectable independent prognostic factor for gastric cancer
Authors: Wang Xi , Wan Fei , Pan Jun , Yu Guan‐Zhen , Chen Ying , Wang Jie‐Jun
Published: December 2007

Background and Objectives

The role of tumor size should not be neglected in the management of gastric cancer and its prognostic value needs precise reevaluation.

Methods

The survival data of 513 patients who underwent radical resection between 2000 and 2005 were collected retrospectively. Tumor size, measured as the maximum diameter of tumor, was categorized into four subgroups (≤2, ≤3, ≤5, >5 cm) using the method of minimizing the estimated average expected distance (AED) objective function. The prognostic value of tumor size and the correlation between tumor size and other clinicopathologic factors were investigated.

Results

In multivariate analysis, status of lymph nodes (P < 0.001), depth of invasion (P < 0.001), type of resection (P = 0.004), age (P = 0.008), tumor size (P = 0.014), and perioperative blood transfusion (P = 0.034) were confirmed as independent prognostic predictors for patients with gastric cancer. Log linear model suggested that the status of lymph nodes and the depth of invasion associated with the tumor size significantly.

Conclusions

The tumor size is a non‐neglectable independent prognostic factor for patients with gastric cancer and more attention should be paid to its role in the management of gastric cancer. J. Surg. Oncol. 2008;97:236–240. © 2007 Wiley‐Liss, Inc.
Macromol. Rapid Commun. 1/2008
Authors: Mi Peng , Chu Liang‐Yin , Ju Xiao‐Jie , Niu Catherine Hui
Published: December 2007

Cover: The cover picture shows the ion‐induced negative‐shift of the lower critical solution temperature (LCST) of a novel thermo‐responsive smart copolymer. After capturing the guest potassium ions, the LCST value of the copolymer changes from LCSTb to LCSTa. The ion‐responsive behavior of the smart polymer is similar to the behavior of Venus flytraps. Further details can be found in the article by P. Mi, L.‐Y. Chu,* X.‐J. Ju, and C. H. Niu on page 27.
The effects of proteoglycan surface patterning on neuronal pathfinding
Authors: Hlady V. , Hodgkinson G.
Published: December 2007

Protein micropatterning techniques are increasingly applied in cell choice assays to investigate fundamental biological phenomena that contribute to the host response to implanted biomaterials, and to explore the effects of protein stability and biological activity on cell behavior for in vitro cell studies. In the area of neuronal regeneration the protein micropatterning and cell choice assays are used to improve our understanding of the mechanisms directing nervous system during development and regenerative failure in the central nervous system (CNS) wound healing environment. In these cell assays, protein micropatterns need to be characterized for protein stability, bioactivity, and spatial distribution and then correlated with observed mammalian cell behavior using appropriate model system for CNS development and repair. This review provides the background on protein micropatterning for cell choice assays and describes some novel patterns that were developed to interrogate neuronal adaptation to inhibitory signals encountered in CNS injuries.
Aspects of BMP‐2 binding to receptors and collagen: Influence of cell senescence on receptor binding and absence of high‐affinity stoichiometric binding to collagen.
Authors: Laub M. , Chatzinikolaidou M. , Jennissen H. P.
Published: December 2007

On the basis of their osteoinductive properties bone morphogenetic proteins (BMPs) are used today in clinical therapy such as the treatment of spinal disorders or healing defects in tibia fractures. A major biochemical function of these molecules is their binding to a large number of other proteins to fulfil their biological role. Two of these BMP‐binding proteins are the cellular BMP‐receptor and the collagen molecule which has been implicated as a specific BMP binding protein from the beginning of BMP‐2 research. These two molecules are the subject of this paper. In receptor binding one must distinguish between the binding function (θ) and the state function (r). The binding function describes the equilibrium between effector (e.g. BMP‐2) and the receptor, whereas the state function describes the change in receptor activation elicted by the effector resulting in downstream effects such as the induction of alkaline phosphatase. In studies on the state function of rhBMP‐2 binding to MC3T3‐E1 cells it will be shown that the binding affinity of the receptor decreases fivefold in a highly significant manner (p <0.0002, n = 10, duplicate assays) with the serial passage number from 1.7 ± 0.3 nM as measured with passage 5 cells to 8.9 ± 1.5 nM as measured with passage 10 cells. Since the serial passage model of MC3T3‐E1 cells is a model of senescence it is concluded that the affinity of the rhBMP‐2 receptor interaction decreases with senescence i.e. age. This may have important consequences for the age dependent dosage of rhBMP‐2 in the clinic. In a second series of experiments it will be shown that contrary to widespread belief, BMP‐2 does not show a high affinity stoichiometric binding to collagen as measured by affinity chromatography on collagen Sepharose and in solution by gel filtration. A review of the literature and evaluation of binding stoichiometry, interestingly supported our finding since the calculated stoichiomerties indicate a binding of 10‐3 to 10‐4 mol BMP/mol tropocollagen. It is suggested that collagen is substituted by porous calcium phosphates and metals as carriers for BMP applications.
Preparation and thermal properties of a novel UV‐cured star polyurethane acrylate coating
Authors: Chen Xilei , Hu Yuan , Song Lei , Jiao Chao
Published: December 2007

A novel star polyurethane acrylate (SPUA) used for UV‐curable coating was prepared from 2,4‐toluene diisocyanate, 2‐hydroxyethyl arcylate, and hexakis(2‐hydroxyethyl)melamine, and characterized using FTIR, 1H‐NMR, and elemental analysis. Its UV curing behaviors investigated via FTIR clearly indicated that this monomer could be cured rapidly at air atmosphere. The conversion of the unsaturated bond of the cured monomer sample is near to 72% after exposed under UV light for 40 sec. The hardness, flexibility, and mechanical properties of the cured film were also investigated. The thermal stability of the cured film was studied using thermogravimetric analysis (TGA) and real time Fourier transform infrared (RTFTIR). Results showed that this oligomer has some superior properties and can be used for UV curing coating. Copyright © 2007 John Wiley & Sons, Ltd.
Bone marrow‐derived myofibroblasts contribute functionally to scar formation after myocardial infarction
Authors: van Amerongen MJ , Bou‐Gharios G , Popa ER , van Ark J , Petersen AH , van Dam GM , van Luyn MJA , Harmsen MC
Published: December 2007

Myofibroblasts play a major role in scar formation during wound healing after myocardial infarction (MI). Their origin has been thought to be interstitial cardiac fibroblasts. However, the bone marrow (BM) can be a source of myofibroblasts in a number of organs after injury. We have studied the temporal, quantitative and functional role of BM‐derived (BMD) myofibroblasts in myocardial scar formation. MI was induced by permanent coronary artery ligation in mice reconstituted with EGFP or pro‐Col1A2 transgenic BM. In the latter, luciferase and β‐galactosidase transgene expression mirrors that of the endogenous pro‐collagen 1A2 gene, which allows for functional assessment of the recruited cells. After MI, α‐SMA‐positive myofibroblasts and collagen I gradually increased in the infarct area until day 14 and remained constant afterwards. Numerous EGFP‐positive BMD cells were present during the first week post‐MI, and gradually decreased afterwards until day 28. Peak numbers of BMD myofibroblasts, co‐expressing EGFP and α‐SMA, were found on day 7 post‐MI. An average of 21% of the BMD cells in the infarct area were myofibroblasts. These cells constituted up to 24% of all myofibroblasts present. By in vivo IVIS® imaging, BMD myofibroblasts were found to be active for collagen I production and their presence was confined to the infarct area. These results show that BMD myofibroblasts participate actively in scar formation after MI. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Substituent effect study on 13Cβ SCS of styrene series. A Yukawa–Tsuno model and Reynolds dual substituent parameter model investigation
Authors: Saleh Basil A. , Al‐Shawi Sabih A. , Fadhil Ghazwan F.
Published: December 2007

The Yukawa–Tsuno (Y–T) and Reynolds dual substituent parameter (DSP) models have been used to model 13C substituent chemical shift (SCS) of the Cβ atom of 19 series of para‐substituted styrenes (X‐C6H4CRCYW) with variable electronic and structural demands in the side‐chain. The best fit of the Y–T model was better than that of the Reynolds DSP model for most of the studied series. A high correlation was found between the ρ value of the Y–T model and ρF value of the Reynolds DSP model. The ρ value, which reflects the sensitivity of 13Cβ SCS to the substituent field effect, was found to be influenced by the group W on the Cβ atom. A W group that enhances the para‐substituent π‐polarization of the side‐chain has a higher ρ value than its counterpart W groups that induce counter π‐polarization in the side‐chain. The series with W in an E‐configuration to the aryl ring has higher ρ value than corresponding Z series. A lower ρ value is observed when W induces a counter π‐polarization of the side‐chain (as with NO2 and COMe) or when the R substituent imposes a 65° dihedral angle between the side‐chain and the para‐substituted benzene ring (as with t‐Bu). When the W group is a heterocyclic ring, the closer the heteroatom is to Cβ, the lower the ρ value is due to the greater counter π‐polarization. The two components of the substituent effect on 13C
β SCS, namely the field effect and resonance effect, behave inversely. The resonance demand (r+ value) increases, as the Y and/or W groups become more electron‐withdrawing (EW). The series with W as a hetrocyclic ring develop negative charge at the carbon atom of the hetrocyclic ring adjacent to Cβ (and to which the styryl moiety is attached) and has a lower r+ value than those which fail to do so. The lowest r+ value was for those series with a 65° dihedral angle. Copyright © 2007 John Wiley & Sons, Ltd.
Lack of the neighboring group rate effect in solvolytic reactions that proceed via participation
Authors: Jurić Sandra , Kronja Olga
Published: December 2007

In order to investigate the influence of solvent polarity on the rate effect of double bonds in reactions that proceed via an extended π‐participation mechanism, the solvolysis rates (kU) of the benzyl chloride derivative 1 and tertiary chloride 2 that have doubly unsaturated side chains were measured in absolute ethanol, 80% v/v. aq. ethanol and 97% wt. aq. trifluoroethanol. The rates of the corresponding saturated analogs 1S and 2S (kS) were measured in 80% aq. ethanol and 97% wt. aq. trifluoroethanol, while those in pure ethanol were calculated according to LFER equation log k = sf (Ef + Nf). In solvents with moderate ionizing power (ethanol and 80% aq. ethanol) the expected rate effects were obtained (kU/kS>1), while in solvent with high ionizing power (2,2,2‐trifluoroethanol) absence of the rate effect was observed (kU/kS≈1), indicating that in the kS process the solvation of the transition state is very important, while in kΔ process the breaking of the CCl bond is not appreciably developed in the transition state and the solvent effect is marginal. Copyright © 2007 John Wiley & Sons, Ltd.
Ultra‐high molecular weight poly(ε‐caprolactone) by means of diphenyl bismuth bromide
Authors: Kricheldorf Hans R. , Behnken Gesa , Schwarz Gert
Published: December 2007

Diphenyl bismuth bromide (Ph2BiBr) allows for polymerizations of ε‐caprolactone in bulk at temperatures as low as 40 °C. Time conversion curves indicate a lower reactivity than tin(II) 2‐ethyl hexanoate (SnOct2) plus alcohol at 120 °C and also at 60 °C. Ph2BiBr also proved to be less reactive than Ph2BiOEt, but more reactive than BiBr3 and Bi(III)n‐hexanoate. Small amounts (≤1 wt %) of cyclic oligoester were detectable by MALDI‐TOF mass spectrometry even at a polymerization temperature of 40 °C. The molar masses depend on the monomer–initiator ratio (M/I) but not in a simple parallel manner. With M/I = 600/1 number average molecular weights (Mns, corrected values) around 500 kDa were obtained. Even at low M/Is high molar mass polylactones were found and CH2Br endgroups were not detectable. However, upon addition of tetra(ethylene glycol) the coinitiator was completely incorporated yielding telechelic polylactones and the molar mass increased with the monomer–coinitiator ratio. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 851–859, 2008
Nucleation of gold nanoparticles on latex particle surfaces
Authors: Kim Hyungsoo , Daniels Eric S. , Dimonie Victoria L. , Klein Andrew
Published: December 2007

Gold particles were nucleated on functionalized (i.e., sulfonate or imidazole groups) latex particle surfaces. Gold ions were associated with the functional groups present on the surface of the latex particles by metal‐ligand formation and were then reduced to nucleate gold particles on the particle surface. The use of imidazole groups favored the metal‐ligand formation more effectively compared with sulfonic acid groups, so gold nucleation was investigated on the surface of imidazole‐functionalized model latex particles. The desorption of gold atoms or their surface migration first occurred during the reduction process and then gold nanoparticles were nucleated. The utilization of strong reductants, such as NaBH4 and dimethylamine borane (DMAB) under mildly acidic conditions (i.e., pH 4) led to the deprotonation of imidazole‐rich polymer chains present on the surface of the model latex particles followed by deswelling of hydrophilic polymer surface layers. As a result, well‐dispersed gold nanoparticles were embedded in the hydrophilic polymer surface. On the other hand, the use of weak reductants led to the formation of localized gold aggregates on the surface of the latex particles. The removal of residual styrene monomer is very important because gold ions can be coordinated with the vinyl groups present in styrene monomer and would then be reduced by nucleophilic water addition. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 912–925, 2008
The effects of solvent type and aging on structural development in poly(vinyl chloride) thermoreversible gels
Authors: Hwang Minkyu , Yang Hoichang , Park Sanghyun , Lee Dae Ho , Cho Kilwon
Published: December 2007

We investigated the effects of solvent type (mono‐ester vs. di‐ester solvent) and aging on the structural development in the poly(vinyl chloride)/butyl benzoate (PVC/BB) and PVC/dibutyl phthalate(DBP) gels, as well as on their viscoelastic and mechanical behaviors. It was found that aged PVC/DBP gels held at RT for 7 days exhibit an improvement of about 100% in storage modulus (G′) compared to fresh gels, with a sudden drop in G′ around 50 °C, whereas the storage moduli of the PVC/BB gels decrease monotonically with temperature, irrespective of the postaging time. These different behaviors of the PVC/BB and PVC/DBP gels arise mainly because of the difference in the network structure produced by the formation of the polymer‐solvent complex between the CO groups of the solvent and the polarized hydrogen moieties of PVC, as was confirmed with small angle X‐ray scattering and uniaxial tensile experiments. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 263–271, 2008
Photoluminescence of bridged polysilsesquioxanes containing urea groups: Doping with Safranine‐O to generate red‐light emission
Authors: Gómez M. L. , Fasce D. P. , Williams R. J. J. , Montejano H. A. , Previtali C. M.
Published: December 2007

Bridged polysilsesquioxanes containing urea groups (ureasils) exhibit a broad photoluminescent emission in the visible spectrum. For a particular bridged polysilsesquioxane synthesized by the hydrolytic condensation of a precursor prepared by reaction of 4,4′‐[1,3 phenylenebis‐(1‐methylethylidene)]bis(aniline) (BSA) with 3‐(isocyanatepropyl)triethoxysilane (IPTES), we show that the broad photoluminescent band could be transformed into a relatively narrow emission band located in the red region of the spectra, by doping with Safranine‐O. The spectral overlap between the host emission and the dye absorption generated an efficient energy transfer process (antenna effect). Absorption, emission, and triplet–triplet absorption spectra revealed an efficient dispersion of the dye in the ureasil as well as the presence of strong host‐guest specific interactions. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 289–296, 2008
The polycomb group protein EZH2 regulates actin polymerization in human prostate cancer cells
Authors: Bryant R.J. , Winder S.J. , Cross S.S. , Hamdy F.C. , Cunliffe V.T.
Published: December 2007

BACKGROUND

The Polycomb Group protein EZH2 is implicated in prostate cancer progression. EZH2 promotes prostate cancer cell proliferation and invasiveness. We describe a link between EZH2 function and actin polymerization in prostate cancer cells.

METHODS

Nuclear and cytoplasmic EZH2 expression in benign and malignant prostate tissue samples was assessed. An association between EZH2 function and actin polymerization in prostate cancer cells was investigated using siRNA‐mediated knock‐down of EZH2. Effects of EZH2 knock‐down on actin polymerization dynamics were analyzed biochemically using immunoblot analysis of cell lysate fractions, and morphologically using immunocytochemistry.

RESULTS

Cytoplasmic EZH2 is expressed at low levels in benign prostate epithelial cells and over‐expressed in prostate cancer cells. Cytoplasmic EZH2 expression levels correlate with nuclear EZH2 expression in prostate cancer samples. Knock‐down of EZH2 in PC3 prostate cancer cells increases the amount of F‐actin polymerization, cell size, and formation of actin‐rich filaments.

CONCLUSIONS

Cytoplasmic EZH2 is over‐expressed in prostate cancer cells. EZH2 function promotes a reduction in the pool of insoluble F‐actin in invasive prostate cancer cells. EZH2 may regulate actin polymerization dynamics and thereby promote prostate cancer cell motility and invasiveness. Prostate 68: 255–263, 2008. © 2007 Wiley‐Liss, Inc.
Prostate‐Specific genes and their regulation by dihydrotestosterone
Authors: Ci Ma , Mayumi Yoshioka , André Boivin , Pascal Belleau , Lin Gan , Yasukazu Takase , Fernand Labrie , Jonny St‐Amand
Published: December 2007

BACKGROUND

Prostate is a well‐known androgen‐dependent tissue.

METHODS

By sequencing 4,294,186 serial analysis of gene expression (SAGE) tags, we have investigated the transcriptomes of normal mouse prostate, liver, testis, lung, brain, femur, skin, adipose tissue, skeletal muscle, vagina, ovary, mammary gland, and uterus in order to identify the most abundant and tissue‐specific transcripts in the prostate, as well as to target the androgen responsive transcripts specifically regulated in the prostate. Small interference RNA (siRNA) in LNCaP cells was applied to validate the roles of prostate‐specific/enriched ARGs in the growth of human prostate cancer cells.

RESULTS

The most abundant transcripts were involved in prostatic secretion, energy metabolism and immunity. Previously well‐known prostate‐specific transcripts, including many transcripts involved in prostatic secretion, polyamine biosynthesis and transport, and immunity were specific/enriched in the prostate. Only 22 transcripts among 114 androgen‐regulated genes (ARGs) in the mouse prostate were modulated by dihydrotestosterone (DHT) in two or more tissues. The siRNA results showed that inhibition of HSPA5 and MAT2A gene expression repressed growth of human cancer LNCaP cells.

Conclusions

The current study globally assessed the transcriptome of the prostate and revealed the most abundant and tissue‐specific transcripts which are responsible for the unique functions of this organ. These prostate‐specific ARGs might be used as targets to develop safe and effective gene‐based therapy for the prevention and treatment of prostate cancer. Prostate 68: 241–254, 2008. © 2007 Wiley‐Liss, Inc.
Characterization of bovine surfactant proteins B and C by electrospray ionization mass spectrometry
Authors: Liu Suya , Zhao Lin , Manzanares Dahis , Doherty‐Kirby Amanda , Zhang Cunjie , Possmayer Fred , Lajoie Gilles A.
Published: December 2007

Bovine surfactant proteins B (SP‐B) and C (SP‐C) were analyzed by nano‐electrospray ionization mass spectrometry (nano‐ESI‐MS). The observed molecular masses showed discrepancies compared to the calculated molecular masses using the published amino acid sequences. The number of cysteine residues in the published bovine SP‐B amino acid sequences also failed to match the observed mass shift upon reduction of the SP‐B dimer. To determine the amino acid sequences of two proteins, SP‐B was first digested with trypsin and analyzed by liquid chromatography/tandem mass spectrometry (LC/MS/MS), while SP‐C was analyzed by MS/MS in its intact form. The amino acid sequence of bovine SP‐B determined here matches the observed molecular mass. The sequence is almost identical to the sheep SP‐B except for two amino acid residues, consistent with the proximity of the two species. The correct sequence contains seven cysteine residues. Bovine SP‐B exists as dimers and all cysteines are oxidized to form disulfide bonds in physiological conditions, which is in agreement with the observed mass shift upon reduction of the SP‐B dimer. These cysteine residues are completely conserved across all species indicating their importance for the biological functions of this surfactant protein. The sequence of SP‐C determined here also reveals an L to V substitution at its position 22 compared with the published bovine SP‐B sequence. Copyright © 2007 John Wiley & Sons, Ltd.
Considerations for the design of organic mulch permeable reactive barriers
Authors: Ahmad Farrukh , McGuire Travis M. , Lee Robert S. , Becvar Erica
Published: December 2007

Organic mulch consists of insoluble carbon biopolymers that are enzymatically hydrolyzed during decomposition to release aqueous total organic carbon (TOC). The released TOC is utilized by microorganisms as an electron donor to transform electrophilic contaminants via reductive pathways. Over the last decade, organic mulch permeable reactive barriers (PRBs), or biowalls, have received increased interest as a relatively inexpensive slow‐release electron donor technology for addressing contaminated groundwater. To date, biowalls have been installed to enhance the passive bioremediation of groundwater contaminated with a variety of electrophilic compounds, including chlorinated solvents, explosives, and perchlorate. In addition, several mulch biowall projects are currently under way at several U.S. Department of Defense facilities. However, at the present time, the guidelines available for the design of mulch PRBs are limited to a few case studies published in the technical literature. A biowall design, construction, and operation protocol document is expected to be issued by the Air Force Center for Environmental Excellence in 2007. In this publication, three technical considerations that can have a significant impact on the design and performance of mulch PRBs are presented and discussed. These technical considerations are: (1) hydraulic characteristics of the mulch bed; (2) biochemical characteristics of different types of organic amendments used as mulch PRB fill materials; and (3) a transport model that can be used to estimate the required PRB thickness to attain cleanup standards. © 2007 Wiley Periodicals, Inc.
Bayesian modeling of multivariate average bioequivalence
Authors: Ghosh Pulak , Gönen Mithat
Published: December 2007

Bioequivalence trials are usually conducted to compare two or more formulations of a drug. Simultaneous assessment of bioequivalence on multiple endpoints is called multivariate bioequivalence. Despite the fact that some tests for multivariate bioequivalence are suggested, current practice usually involves univariate bioequivalence assessments ignoring the correlations between the endpoints such as AUC and Cmax. In this paper we develop a semiparametric Bayesian test for bioequivalence under multiple endpoints. Specifically, we show how the correlation between the endpoints can be incorporated in the analysis and how this correlation affects the inference. Resulting estimates and posterior probabilities ‘borrow strength’ from one another where the amount and the direction of the strength borrowed are determined by the prior correlations. The method developed is illustrated using a real data set. Copyright © 2007 John Wiley & Sons, Ltd.
Analysis of recurrent event data under the case‐crossover design with applications to elderly falls
Authors: Luo Xianghua , Sorock Gary S.
Published: December 2007

The case‐crossover design is useful for studying the effects of transient exposures on short‐term risk of diseases or injuries when only data on cases are available. The crossover nature of this design allows each subject to serve as his/her own control. While the original design was proposed for univariate event data, in many applications recurrent events are encountered (e.g. elderly falls, gout attacks, and sexually transmitted infections). In such situations, the within‐subject dependence among recurrent events needs to be taken into account in the analysis. We review three existing conditional logistic regression (CLR)‐based approaches for recurrent event data under the case‐crossover design. A simple approach is to use only the first event for each subject; however, we would expect loss of efficiency in estimation. The other two reviewed approaches rely on independence assumptions for the recurrent events, conditionally on a set of covariates. Furthermore, we propose new methods that adjust the CLR using either a within‐subject pairwise resampling technique or a weighted estimating equation. No specific dependency structure among recurrent events is needed therein, and hence, they have more flexibility than the existing methods in the situations with unknown correlation structures. We also propose a weighted Mantel–Haenszel estimator, which is easy to implement for data with a binary exposure. In simulation studies, we show that all discussed methods yield virtually unbiased estimates when the conditional independence assumption holds. These methods are illustrated using data from a study of the effect of medication changes on falls among the elderly. Copyright © 2007 John Wiley & Sons, Ltd.
Grammar‐driven generation of domain‐specific language debuggers
Authors: Wu Hui , Gray Jeff , Mernik Marjan
Published: December 2007

Domain‐specific languages (DSLs) assist a software developer (or end‐user) in writing a program using idioms that are similar to the abstractions found in a specific problem domain. Tool support for DSLs is lacking when compared with the capabilities provided for standard general‐purpose languages (GPLs), such as Java and C++. For example, support for debugging a program written in a DSL is often non‐existent. The lack of a debugger at the proper abstraction level limits an end‐user's ability to discover and locate faults in a DSL program. This paper describes a grammar‐driven technique to build a debugging tool generation framework from existing DSL grammars. The DSL grammars are used to generate the hooks needed to interface with a supporting infrastructure constructed for an integrated development environment that assists in debugging a program written in a DSL. The contribution represents a coordinated approach to bring essential software tools (e.g. debuggers) to different types of DSLs (e.g. imperative, declarative, and hybrid). This approach hides from the end‐users the accidental complexities associated with expanding the focus of a language environment to include debuggers. The research described in this paper addresses a long‐term goal of empowering end‐users with development tools for particular DSL problem domains at the proper level of abstraction without depending on a specific GPL. Copyright © 2007 John Wiley & Sons, Ltd.
Roscovitine inhibits ERK1/2 activation induced by angiotensin II in vascular smooth muscle cells
Authors: Li Ai-Ying , Han Mei , Zheng Bin , Wen Jin-Kun
Published: December 2007

Roscovitine is a potent CDK inhibitor often used as a biological tool in cell‐cycle studies, but its working mechanism and real targets in vascular smooth muscle cells (VSMCs) remain unclear. In this study, we observed that ERK1/2 phosphorylation induced by Ang II was abrogated by pretreating VSMCs with roscovitine for 15 h. Pretreating VSMCs with roscovitine also inhibited Ang II‐induced c‐Jun expression and phosphorylation. We further demonstrated that roscovitine could suppress the DNA binding activity of c‐Jun and activation of angiotensinogen promoter by Ang II. These results suggest that roscovitine represses Ang II‐induced angiotensinogen expression by inhibiting activation of ERK1/2 and c‐Jun.
Lexical frequency and third-graders' stress accuracy in derived English word production
Authors: JARMULOWICZ LINDA , TARAN VALENTINA L. , HAY SARAH E.
Published: December 2007

This study examined the effects of lexical frequency on children's production of accurate primary stress in words derived with nonneutral English suffixes. Forty-four third-grade children participated in an elicited derived word task in which they produced high-frequency, low-frequency, and nonsense-derived words with stress-changing suffixes (i.e., -tion, -ic, -ity). Derived word frequency affected stress production accuracy; however, the individual suffix also played an important role in stress placement, with -tionproductions more accurate than either -icor -ityproductions. For the real words, derived word frequencyrelativeto stem frequency was related to performance. Stress was less accurate on derived words that were much lower in frequency than their stems (e.g.,tranquil/tranquility) and more accurate on derived words that approximated or exceeded their stem frequency (e.g.,motivate/motivation). In addition to derived word and stem frequency, results are discussed with reference to several phonological characteristics that may also influence stress production accuracy.
The effects of training on automatization of word recognition in English as a foreign language
Authors: AKAMATSU NOBUHIKO
Published: December 2007

The present study investigated the effects of word-recognition training on the word-recognition processing of learners of English as a foreign language (EFL). Providing 7-week word-recognition training, the study examined whether such training improves EFL learners' word-recognition performance. The main aspects of this study concerned word frequency and working-memory capacity in automatization of word recognition. Analysis of variance and correlational analyses revealed qualitative differences in the improvement of EFL word-recognition performance with respect to word frequency. The improvement in the processing of high-frequency words was associated with simple speedup; conversely, the processing of low-frequency words was associated with automatization. Results also showed that working-memory capacity might not play a noticeable role in improving word-recognition speed or efficiency.