bluuebunny/crossref_metadata_2025 huggingface dataset:
Ferric Chloride Hexahydrate‐Catalyzed Highly Regio‐ and Stereoselective Conjugate Addition Reaction of 2,3‐Allenoates with Grignard Reagents: An Efficient Synthesis of β,γ‐Alkenoates
Authors: Chai Guobi , Lu Zhan , Fu Chunling , Ma Shengming
Published: July 2009

Ferric chloride hexahydrate was shown to be an efficient catalyst for the conjugate addition of 2,3‐allenoates with alkyl‐, aryl‐, or vinyl‐Grignard reagents to synthesize polysubstituted β,γ‐unsaturated alkenoates with high regio‐ and stereoselectivity. The in situ formed magnesium dienolate may readily react with different electrophilic reagents under different reaction conditions with or without a catalyst to construct an allylic quaternary carbon at the α‐position of the ester group and a stereocontrollable retention of the carbon‐carbon double bond.
LiClO4‐doped plasticized chitosan as biodegradable polymer gel electrolyte for supercapacitors
Authors: Kumar M. Selva , Bhat D. Krishna
Published: July 2009

Studies on redox supercapacitors using electronically conducting polymers are of great importance for hybrid power sources and pulse power applications. In this study, electrochemical properties of a chitosan‐based biodegradable polymer gel electrolyte (PGE) and a p/p polypyrrole supercapacitor fabricated using this electrolyte have been investigated. The variation of conductivity and dielectric properties of the electrolyte film with temperature has also been measured. The PGE film chosen for the study exhibited a specific conductivity of 5.5 × 10−3 S cm−1. The electric modulus of the electrolyte film exhibits a long tail feature indicative of good capacitance. The fabricated supercapacitor showed a fairly good specific capacitance of 120 F g−1 and a time constant of 1 s. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
The synthesis of poly(butylene terephthalate) from terephthalic acid, part I: The influence of terephthalic acid on the tetrahydrofuran formation
Authors: Devroede Jan , Duchateau Robbert , Koning Cor E. , Meuldijk Jan
Published: July 2009

An in depth study is performed on the origin of and influences on the formation of tetrahydrofuran (THF) during the first stage of the terephthalic acid (TPA) based synthesis of poly(butylene terephthalate) (PBT). Although many improvements on the synthesis process of PBT have been reported in literature to suppress this undesired side reaction, only few studies reported on the actual mechanism of the THF formation, which is not completely understood. Low molecular weight compounds have been used to model the side reactions occurring during the polymerization reaction. It could be concluded that, in contrast to previous reportage, only the THF formation from the monomer, 1,4‐butanediol, is directly influenced by the use of TPA as a starting material for the production of PBT. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Development of porous UHMWPE morphologies for fixation of gel‐based materials
Authors: Plumlee Kevin , Schwartz Christian J.
Published: July 2009

Novel gel‐based materials including hydrogels and bioderived polymers show great potential in orthopedics but require a means of mechanical fixation to a substrate. The development of controlled porous ultra‐high‐molecular‐weight polyethylene (UHMWPE) morphologies is targeted to expand the future potential for UHMWPE‐based composites with such novel bioderived materials. Porous UHMWPE morphologies were produced by means of a sodium chloride leaching process. Compression‐molded samples were prepared by dry mixing of sized NaCl particles and UHMWPE powder. These were then soaked in water to remove the porogen, leaving a porous UHMWPE structure. The mass of removed porogen and resulting void density were found to match well with Monte Carlo simulations. Distribution of NaCl particles was greatly influenced by the ratio of particle sizes between NaCl and UHMWPE. Limited percolation was achievable at NaCl concentrations below 50 wt %, whereas porogen concentrations above 60 wt % led to interconnected networks. Porous UHMWPE scaffolds were impregnated with gelatin to explore the penetration of a gel‐based phase. It was observed that the gelatin was able to permeate the UHMWPE to a great extent, except for unfilled voids due either to entrapped air or insufficient channel diameters to accommodate gelatin flow. These results confirm that porous morphologies can be created in a controlled manner and tailored for chosen applications. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Synthesis of ion‐imprinting chitosan/PVA crosslinked membrane for selective removal of Ag(I)
Authors: Shawky Hosam A.
Published: July 2009

A novel ion‐imprinted membranes were synthesized for selective removal and preconentration for Ag(I) ions from aqueous solutions. The membranes were obtained via crosslinking of chitosan (CS), PVA, and blend chitosan/PVA using glutaraldehyde (GA) as crosslinker. The FTIR spectra were used to confirm the membrane formation. Comparing with the nonimprinted membranes, Ag(I)‐imprinted CS and CS/PVA has higher removal capacity and selectivity for Ag+ ions. An enhancement in the Ag+ removal capacity by ∼ 20% (from 77.8 to 94.4 mg g–1) and ∼ 50% (from 83.9 to 125 mg g–1) was found in the Ag(I)‐imprinted CS and Ag(I)‐imprinted CS/PVA membranes, respectively, when compared with the nonimprinted membranes. Removal equilibra was achieved in about 40 min for the non‐ and ion‐imprinted CS/PVA. The pH and temperature significantly affected the removal capacity of ion‐imprinted membrane. The relative selectivity coefficient values of Ag+/Cu2+ and Ag+/Ni2+ are 9 and 10.7 for ion‐imprinted CS membrane and 11.1 and 15 for ion‐imprinted CS/PVA membrane when compared with nonimprinted membranes. The imprinted membranes can be easily regenerated by 0.01M EDTA and therefore can be reused at least five times with only 15% loss of removal capacity. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Poly(lactide acid) composites reinforced with fibers obtained from different tissue types of Picea sitchensis
Authors: Gregorova A. , Hrabalova M. , Wimmer R. , Saake B. , Altaner C.
Published: July 2009

Wood fibers vary in their properties across species, across trees of the same species, and within single trees. This work takes advantage of wood fibers reinforcing poly(lactic acid) composites that originate from different tissue types of the species Sitka spruce (Picea sitchensis). Fibers were prepared with high temperature thermo‐mechanical processing (TMP) from juvenile, mature, and compression wood tissues of Sitka spruce. Composites were made by solution casting with subsequent hot‐pressing. Thermal as well as mechanical properties were determined using differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), and tensile testing. The obtained results showed that the chemical and physical properties of different tissue‐type Sitka spruce fibers have significant effects on the thermal and mechanical properties of the Polylactic acid (PLA)/Sitka fiber composites. To increase interfacial compatibility between the hydrophilic fibers and the hydrophobic polymer matrix, the fibers were treated with vinyltrimethoxysilane (VTMO), while PLA was modified with 4,4‐methylene diphenyl diisocyanate (MDI). It was found that PLA/Sitka composites treated with VTMO and MDI exhibited improved thermal and mechanical properties, compared to the unmodified control. The work also demonstrates that there is potential to improve biobased composites by utilizing the natural variability of wood fibers. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Structure and properties of an organic rectorite/poly(methyl methacrylate) nanocomposite gel polymer electrolyte by in situ synthesis
Authors: Chen Fang , Ma Xiaoyan , Qu Xiaohong , Yan Hongxia
Published: July 2009

The synthesis of organic‐modified rectorite (OREC)/polymethyl methacrylate (PMMA) nanocomposite gel polymer electrolyte (NGPE) via in situ polymerization was investigated using free radical initiator in an solution, in which organic plasticizer, propylene carbonate(PC) acted as a solvent. A serious of NGPE membranes with different OREC content were prepared and characterized. The dispersion and exfoliation statuses of the OREC in the prepared NGPE membranes were analyzed through X‐ray diffraction (XRD) and transmission electron microscope (TEM), and the results indicated that for the NGPE with 5 wt % OREC membrane, OREC was partly exfoliated and well dispersed in the gel polymer electrolyte system. The electrochemical properties of the NGPE were determined by alternating current (AC) impedance spectroscopy, which illustrated that the ionic conductivity of the nanocomposite gel polymer electrolyte firstly increased and then decreased with increasing OREC content. Meanwhile, the maximum value of ionic conductivity for nanocomposite gel polymer electrolytes was obtained when organic clay amount was 5 wt %. The interactions among the components of the NGPE were investigated by Fourier transform infrared (FTIR) spectroscopy. It was shown that there were specific interactions between OREC and the other components, which may influence the conductivity and the stability of GPEs. Finally, an thermal stability enhancement was presented by NGPE with 5 wt % OREC compared with GPE, which was determined by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Corporate social responsibility and sustainability reporting on the Internet
Authors: Morhardt J. Emil
Published: July 2009

All material related to environmental and social performance on the corporate internet sites of 454 Fortune Global 500 and Fortune 1000 companies in 25 industrial sectors was analyzed using the Pacific Sustainability Index. Maximum scores for individual sectors were 20–75 percent of the total possible, highest in the largest and most environmentally sensitive sectors and ranging generally linearly, as shown by plotting score versus rank, down to nearly zero in every sector. None of the variation in score is explained by corporate revenue in the Asian and European firms in this sample (revenues greater than about $9 billion), but there is a very weak correlation between score and revenue for American firms of this size, and a stronger one when Fortune 1000 companies (all American) with revenues smaller than this are included, suggesting that, as corporate size reaches a certain threshold, sustainability reporting becomes independent of it. Copyright © 2009 John Wiley & Sons, Ltd and ERP Environment.
Stereocontrolled Cyclic Nitrone Cycloaddition Strategy for the Synthesis of Pyrrolizidine and Indolizidine Alkaloids
Authors: Brandi Alberto , Cardona Francesca , Cicchi Stefano , Cordero Franca M. , Goti Andrea
Published: July 2009

The synthesis of polyhydroxylated indolizidines and pyrrolizidines belonging to the class of iminosugars, endowed with a vast and assorted biological activity, can be achieved in a straightforward manner by a general strategy consisting of a highly stereoselective 1,3‐dipolar cycloaddition of polyhydroxylated pyrroline‐N‐oxides followed by simple transformations of the isoxazolidine adducts. The strategy allows the complete control of the relative and absolute stereochemistry of the numerous stereogenic centers decorating these compounds.
Rice Husk Ash as a Low Cost Adsorbent for the Removal of Methylene Blue and Congo Red in Aqueous Phases
Authors: Chowdhury Anirban K. , Sarkar Anupam D. , Bandyopadhyay Amitava
Published: July 2009

Adsorption is of significant importance for effluent treatment, especially for the treatment of colored effluent generated from the dyeing and bleaching industries. Low cost adsorbents have gained attention over the decades as a means of achieving very high removal efficiencies to meet effluent discharge standards. The present article reports on batch investigations for color removal from aqueous solutions of Methylene Blue (MB) and Congo Red (CR) using Rice Husk Ash (RHA) as an alternative low cost adsorbent. The performance analysis was carried out as a function of various operating parameters, such as initial concentration of dye, adsorbent dose, contact time, shaker speed, interruption of shaking and ionic concentration. Performance studies revealed that a very high percentage removal of color was achievable for both dyes. The maximum percentage removal of MB was 99.939%, while 98.835% removal was observed for CR. These percentage removals were better than existing systems. Detailed data analysis indicated that adsorption of MB followed the Temkin isotherm, while CR followed the Freundlich isotherm. These isotherms were feasible within the framework of experimentation. Batch kinetic data, on the other hand, indicated that pseudo second order kinetics governed adsorption in both cases. Sensitivity analysis further indicated that the effects of initial dye concentration, shaker speed, pH and ionic strength had no noticeable effect on the percentage dye removal at equilibrium. Batch desorption studies revealed that 50% acetone solution was optimum for CR, while desorption of MB varied directly with acetone concentration.
Design and verification of peripheral control circuits in Esterel
Authors: Singh S.
Published: July 2009

We present a case study showing how an existing concurrent programming language can be used to produce either efficient control‐oriented circuits or embedded software from the same description. This description is also amenable to fully automatic formal verification and can be used to produce pairs of reconfigurable components which can be dynamically scheduled into either hardware or software resources. By using an existing concurrent language we increase the productivity because we can make use of readily available tools for debugging, analysis and verification. We believe that a language and a system that generates good software and hardware is a promising starting point for helping mainstream software developers target future manycore systems which will comprise a mixture of software and hardware components as well as provide a valuable technique for producing interchangeable reconfigurable components for run‐time reconfigurable FPGAs. Copyright © 2007 S. Singh. [Correction made here after
initial online publication]
Spatiotemporal Kinetics in Solution Studied by Time‐Resolved X‐Ray Liquidography (Solution Scattering)
Authors: Kim Tae Kyu , Lee Jae Hyuk , Wulff Michael , Kong Qingyu , Ihee Hyotcherl
Published: July 2009

Information about temporally varying molecular structure during chemical processes is crucial for understanding the mechanism and function of a chemical reaction. Using ultrashort optical pulses to trigger a reaction in solution and using time‐resolved X‐ray diffraction (scattering) to interrogate the structural changes in the molecules, time‐resolved X‐ray liquidography (TRXL) is a direct tool for probing structural dynamics for chemical reactions in solution. TRXL can provide direct structural information that is difficult to extract from ultrafast optical spectroscopy, such as the time dependence of bond lengths and angles of all molecular species including short‐lived intermediates over a wide range of times, from picoseconds to milliseconds. TRXL elegantly complements ultrafast optical spectroscopy because the diffraction signals are sensitive to all chemical species simultaneously and the diffraction signal from each chemical species can be quantitatively calculated from its three‐dimensional atomic coordinates and compared with experimental TRXL data. Since X‐rays scatter from all the atoms in the solution sample, solutes as well as the solvent, the analysis of TRXL data can provide the temporal behavior of the solvent as well as the structural progression of all the solute molecules in all the reaction pathways, thus providing a global picture of the reactions and accurate branching ratios between multiple reaction pathways. The arrangement of the solvent around the solute molecule can also be extracted. This review summarizes recent developments in TRXL, including technical innovations in synchrotron beamlines and theoretical analysis of TRXL data, as well as several examples from simple molecules to an organometallic complex, nanoparticles, and proteins in solution. Future potential applications of TRXL in femtosecond studies and biologically relevant molecules are also briefly mentioned.
Clinical evaluation of a simple image cytometer for CD4 enumeration on HIV‐infected patients
Authors: Li Xiao , Breukers Christian , Ymeti Aurel , Pattanapanyasat Kovit , Sukapirom Kasama , Terstappen Leon W. M. M. , Greve Jan
Published: July 2009

Background:

Affordable, easy‐to‐use, and reliable CD4+ T lymphocyte enumeration systems are needed in resource‐constrained settings to monitor HIV.

Methods:

A simple image cytometer was used to count fluorescently labeled CD4+ T and CD8+ T lymphocytes from CD3 immunomagnetically selected cells on blood specimens of 460 HIV‐1‐infected patients in Siriraj Hospital, Bangkok, Thailand. Results were compared with flow cytometry (FCM).

Results:

CD4+ T lymphocyte counts by image cytometer were comparable (R ≥ 0.97) with those by the FACSCount and the FACScan with a bias of 7.3 and 9.1%, respectively. At very low CD4+ T lymphocyte counts (≤50/μl) some over‐count outliers were observed by the FACScan and image cytometer when compared with the FACSCount. For CD8 enumeration, the image cytometer showed a good correlation (R = 0.96) and a consistent undercount (∼17%) when compared with the FACSCount.

Conclusions:

Evaluation of the image cytometer for CD4 and CD8 enumeration demonstrated comparable results with FCM on a population of HIV‐1‐infected patients. The image cytometer is a good alternative method for point‐of‐care settings in resource‐constrained countries. © 2009 Clinical Cytometry Society
High density DNA array analysis reveals distinct genomic profiles in a subset of gastrointestinal stromal tumors
Authors: Belinsky Martin G. , Skorobogatko Yuliya V. , Rink Lori , Pei Jianming , Cai Kathy Q. , Vanderveer Lisa A. , Riddell David , Merkel Erin , Tarn Chi , Eisenberg Burton L. , von Mehren Margaret , Testa Joseph R. , Godwin Andrew K.
Published: July 2009

Gastrointestinal stromal tumors (GISTs) generally harbor activating mutations in KIT or platelet‐derived growth facter receptor (PDGFRA). Mutations in these receptor tyrosine kinases lead to dysregulation of downstream signaling pathways that contribute to GIST pathogenesis. GISTs with KIT or PDGFRA mutations also undergo secondary cytogenetic alterations that may indicate the involvement of additional genes important in tumor progression. Approximately 10–15% of adult and 85% of pediatric GISTs do not have mutations in KIT or in PDGFRA. Most mutant adult GISTs display large‐scale genomic alterations, but little is known about the mutation‐negative tumors. Using genome‐wide DNA arrays, we investigated genomic imbalances in a set of 31 GISTs, including 10 KIT/PDGFRA mutation‐negative tumors from nine adults and one pediatric case and 21 mutant tumors. Although all 21 mutant GISTs exhibited multiple copy number aberrations, notably losses, eight of the 10 KIT/PDGFRA mutation‐negative GISTs exhibited few or no genomic alterations. One KIT/PDGFRA mutation‐negative tumor exhibiting numerous genomic changes was found to harbor an alternate activating mutation, in the serine‐threonine kinase BRAF. The only other mutation‐negative GIST with significant chromosomal imbalances was a recurrent metastatic tumor found to harbor a homozygous deletion in chromosome arm 9p. Similar findings in several KIT‐mutant GISTs identified a minimal overlapping region of deletion of ∼0.28 Mbp in 9p21.3 that includes only the CDKN2A/2B genes, which encode inhibitors of cell‐cycle kinases. These results suggest that GISTs without activating kinase mutations, whether pediatric or adult, generally exhibit a much lower level of cytogenetic progression than that observed in mutant GISTs. © 2009 Wiley‐Liss, Inc.
Neural representation of anxiety and personality during exposure to anxiety‐provoking and neutral scenes from scary movies
Authors: Straube Thomas , Preissler Sandra , Lipka Judith , Hewig Johannes , Mentzel Hans‐Joachim , Miltner Wolfgang H.R.
Published: July 2009

Some people search for intense sensations such as being scared by frightening movies while others do not. The brain mechanisms underlying such inter‐individual differences are not clear. Testing theoretical models, we investigated neural correlates of anxiety and the personality trait sensation seeking in 40 subjects who watched threatening and neutral scenes from scary movies during functional magnetic resonance imaging. Threat versus neutral scenes induced increased activation in anterior cingulate cortex, insula, thalamus, and visual areas. Movie‐induced anxiety correlated positively with activation in dorsomedial prefrontal cortex, indicating a role for this area in the subjective experience of being scared. Sensation seeking‐scores correlated positively with brain activation to threat versus neutral scenes in visual areas and in thalamus and anterior insula, i.e. regions involved in the induction and representation of arousal states. For the insula and thalamus, these outcomes were partly due to an inverse relation between sensation seeking scores and brain activation during neutral film clips. These results support models predicting cerebral hypoactivation in high sensation seekers during neutral stimulation, which may be compensated by more intense sensations such as watching scary movies. Hum Brain Mapp, 2010. © 2009 Wiley‐Liss, Inc.
New school in liver development: Lessons from zebrafish #
Authors: Chu Jaime , Sadler Kirsten C.
Published: July 2009

There is significant overlap in the genes and pathways that control liver development and those that regulate liver regeneration, hepatic progenitor cell expansion, response to injury, and cancer. Additionally, defects in liver development may underlie some congenital and perinatal liver diseases. Thus, studying hepatogenesis is important for understanding not only how the liver forms, but also how it functions. Elegant work in mice has uncovered a host of transcription factors and signaling molecules that govern the early steps of hepatic specification; however, the inherent difficulty of studying embryogenesis in utero has driven developmental biologists to seek new systems. The rapidly developing vertebrate zebrafish is a favorite model for embryology. The power of forward genetic screens combined with live real-time imaging of development in transparent zebrafish embryos has highlighted conserved processes essential for hepatogenesis and has uncovered some exciting new players. This review presents the advantages of zebrafish for studying liver development, underscoring how studies in zebrafish and mice complement each other. In addition to their value for studying development, zebrafish models of hepatic and biliary diseases are expanding, and using these small, inexpensive embryos for drug screening has become de rigueur. Zebrafish provide a shared platform for developmental biology and translational research, offering innovative methods for studying liver development and disease. The story of hepatogenesis has something for everyone. It involves transcriptional regulation, cell-cell interaction, signaling pathways, control of cell proliferation and apoptosis, plus morphogenic processes that sculpt vasculature, parenchymal cells, and mesenchyme to form the multifaceted liver. Decades of research on liver development in mice and other vertebrates offer valuable lessons in how the multipotent endoderm is programmed to form a functional liver. Of equal importance are insights that have illuminated the mechanisms by which hepatic progenitors are activated in a damaged liver, how the adult liver regenerates, and, possibly, the basis for engineering liver cells in vitro for cell transplantation to sustain patients with liver failure. Moreover, processes that are key to liver development are often co-opted during pathogenesis. Therefore, reviewing hepatogenesis is informative for both basic and translational researchers. In this review, we bring to light the many advantages offered by the tropical freshwater vertebrate zebrafish (Danio rerio) in studying hepatogenesis. By comparing zebrafish and mice, we highlight how work in each system complements the other and emphasize novel paradigms that have been uncovered using zebrafish. Finally, we highlight exciting efforts using zebrafish to model hepatobiliary diseases. (Hepatology 2009.)
An electromyographic investigation of asymmetric lifting and moving of a load: III. Models for determining muscle activity based on anthropometric characteristics
Authors: Das Biman , Mabaleka Godfrey
Published: July 2009

Regression models for six muscles, the left and right iliocostalis, the left and right erector spinae, and the left and right external oblique, were developed for asymmetry and height effects for floor and knuckle lifts. The models were based on participant anthropometric and other measures. Stepwise regression was performed for developing the prediction models. The models developed were discrete in terms of specific height and asymmetry. © 2009 Wiley Periodicals, Inc.
Mortality in a long‐term follow‐up after treatment of CIN
Authors: Kalliala Ilkka , Dyba Tadeusz , Nieminen Pekka , Hakulinen Timo , Anttila Ahti
Published: July 2009

After treatment of the cervical intraepithelial neoplasia (CIN) cervical cancer incidence remains elevated at least for 20 years. Whether the overall or cervical cancer mortality after treatment of CIN is elevated is unknown. The aim of this study was to determine the long‐term survival and cause‐specific mortality among women treated for CIN. The study population consisted of 7,104 women treated for CIN between 1974 and 2001 and 35,437 individually matched controls. The follow‐up of mortality was based on nationwide registries and closed at death, emigration or December 31, 2005. The possible differences in mortality were assessed using Cox proportional hazard model. With follow‐up time of approximately 630,000 woman‐years, overall 2,781 deaths were observed, 530 among women treated for CIN and 2,251 among reference population (HR 1.1, 95% CI 1.0–1.3). Mortality from any cancer (HR 1.4, 95% CI 1.2–1.7), lung cancer (HR 2.7, 95% CI 1.8–4.1) and HPV‐related anogenital cancer (HR 3.1, 95% CI 1.1–8.6) was higher among CIN patients, but mortality from cervical cancer was not (HR 1.0, 95% CI 0.3–4.0). Elevated cervical cancer incidence after treatment of CIN, documented earlier, did not predict elevation in cervical cancer mortality. This suggests high effectiveness of CIN management. Most of the excess mortality observed among CIN patients was due to increased risk of other cancers. These long‐term mortality patterns should be considered when planning and evaluating the management of CIN lesions and related cervical or other cancer prevention activity.
Expression of microRNA‐221 is progressively reduced in aggressive prostate cancer and metastasis and predicts clinical recurrence
Authors: Spahn Martin , Kneitz Susanne , Scholz Claus‐Jürgen , Stenger Nico , Rüdiger Thomas , Ströbel Philipp , Riedmiller Hubertus , Kneitz Burkhard
Published: July 2009

Emerging evidence shows that microRNAs (miR) are involved in the pathogenesis of a variety of cancers, including prostate carcinoma (PCa). Little information is available regarding miR expression levels in lymph node metastasis of prostate cancer or the potential of miRs as prognostic markers in this disease. Therefore, we analyzed the global expression of miRs in benign, hyperplastic prostate tissue (BPH), primary PCa of a high risk group of PCa patients, and corresponding metastatic tissues by microarray analysis. Consistent with the proposal that some miRs are oncomirs, we found aberrant expression of several miRs, including the downregulation of miR‐221, in PCa metastasis. Downregulation of miR‐221 was negatively correlated with the expression of the proto‐oncogen c‐kit in primary carcinoma. In a large study cohort, the prostate‐specific oncomir miR‐221 was progressively downregulated in aggressive forms of PCa. Downregulation of miR‐221 was associated with clinicopathological parameters, including the Gleason score and the clinical recurrence during follow up. Kaplan–Meier estimates and Cox proportional hazard models showed that miR‐221 downregulation was linked to tumor progression and recurrence in a high risk prostate cancer cohort. Our results showed that progressive miR‐221 downregulation hallmarks metastasis and presents a novel prognostic marker in high risk PCa. This suggests that miR‐221 has potential as a diagnostic marker and therapeutic target in PCa.
Incidence and outcome of acquisition of human papillomavirus infection in women with normal cytology—A population‐based cohort study from Taiwan
Authors: Chao Angel , Chang Chee‐Jen , Lai Chyong‐Huey , Chao Fang‐Yu , Hsu Yi‐Hsien , Chou Hung‐Hsueh , Huang Huei‐Jean , Jung Shih‐Ming , Lin Cheng‐Tao , Cheng Hui‐Hsin , Huang Chu‐Chun , Yang Jung‐Erh , Chang Ting‐Chang
Published: July 2009

Little is known about acquisition of human papillomavirus (HPV) and its outcome among older women with negative HPV testing and normal cytology. A longitudinal 3‐yr follow‐up of nested‐cohort subjects (n = 8825) from a population‐based cervical cancer screening study whose Pap and HPV tests were negative at baseline were conducted. Every active HPV‐negative (n = 413) participant had 12‐mo follow‐ups of Pap smear and HPV testing. Colposcopy was performed if either HPV‐positive or cytology was abnormal. The cytology and histology information of the remaining subjects (passive HPV‐negative, n = 8412) was obtained from national registry database. Median age of participants was 45 yr (range, 30–73 yr). The incidence of new acquisition was 4.2/100 woman‐years. The 3‐yr cumulative total HPV acquisition rate was 11.1% (95% confidence interval [CI]: 8.1–14.1). Increased number of sexual partners (≥2 vs. 1) of the participant was associated with risk of acquisition (odds ratio [OR]: 5.0, 95% CI: 2.0–12.6) by multivariate analysis. Three cases of ≥ cervical intraepithelial neoplasia (CIN) 2 were identified in 3‐yr follow‐up in active HPV‐negative subjects. HPV genotypes in the dysplastic tissue were actually present at baseline samples after reanalysis. From the passive HPV‐negative group, only 1 case progressed to CIN2 probably after HPV acquisition. Negative Pap and HPV tests assured a very low risk of developing ≥ CIN2 within 3 yr despite incident HPV infection.
Sequential BMP‐2/BMP‐7 delivery from polyester nanocapsules
Authors: Yilgor P. , Hasirci N. , Hasirci V.
Published: July 2009

The aim of this study was to develop a nanosized, controlled growth factor release system to incorporate into tissue engineering scaffolds and thus activate the cells seeded in the scaffold. Nanocapsules of poly(lactic acid‐co‐glycolic acid) (PLGA) and poly(3‐hydroxybutyrate‐co‐3‐hydroxyvalerate) (PHBV) were loaded with the bone morphogenetic proteins BMP‐2 and BMP‐7, respectively, and with bovine serum albumin (BSA), the model protein. BSA‐loading efficiency and release kinetics were used to determine the most appropriate nanocapsule pair to achieve the delivery of growth factors in a sequential manner, as occurs in natural processes. BSA‐encapsulation efficiency was highest when the polymer concentration used in the preparation of PLGA and PHBV nanocapsules was 10% (w/v) (84.75% and 16.72%, respectively). Release of BSA was faster from PLGA than it was from PHBV. Based on the encapsulation efficiency and release data, 10% PLGA and 10% PHBV nanocapsules were chosen to provide the early BMP‐2 and later BMP‐7 release, respectively. Simultaneous, sequential delivery and individual release of the BMPs were studied for 7, 14, and 21 days, using rat bone marrow mesenchymal stem cells. Individual BMP‐2 release suppressed cell proliferation while providing higher alkaline phosphatase activity with respect to BMP‐7. The sequential delivery of BMP‐2 and BMP‐7 provided slightly lower proliferation than did simultaneous delivery, but the highest alkaline phosphatase activity of all indicated a synergistic effect on the osteogenic differentiation of mesenchymal stem cells caused by the use of the two growth factors in a sequential fashion. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res, 2010
Interplay of anionic charge, poly(ethylene glycol), and iodinated tyrosine incorporation within tyrosine‐derived polycarbonates: Effects on vascular smooth muscle cell adhesion, proliferation, and motility
Authors: Johnson Patrick A. , Luk Arnold , Demtchouk Aleksey , Patel Hiral , Sung Hak‐Joon , Treiser Matthew D. , Gordonov Simon , Sheihet Larisa , Bolikal Das , Kohn Joachim , Moghe Prabhas V.
Published: July 2009

Regulation of smooth muscle cell adhesion, proliferation, and motility on biomaterials is critical to the performance of blood‐contacting implants and vascular tissue engineering scaffolds. The goal of this study was to examine the underlying substrate‐smooth muscle cell response relations, using a selection of polymers representative of an expansive library of multifunctional, tyrosine‐derived polycarbonates. Three chemical components within the polymer structure were selectively varied through copolymerization: (1) the content of iodinated tyrosine to achieve X‐ray visibility; (2) the content of poly(ethylene glycol) (PEG) to decrease protein adsorption and cell adhesivity; and (3) the content of desaminotyrosyl‐tyrosine (DT), which regulates the rate of polymer degradation. Using quartz crystal microbalance with dissipation, we quantified differential serum protein adsorption behavior because of the chemical components DT, iodinated tyrosine, and PEG: increased PEG content within the polymer structure progressively decreased protein adsorption but the simultaneous presence of both DT and iodinated tyrosine reversed the effects of PEG. The complex interplay of these components was next tested on the adhesion, proliferation, and motility behavior cultured human aortic smooth muscle cells. The incorporation of PEG into the polymer reduced cell attachment, which was reversed in the presence of iodinated tyrosine. Further, we found that as little as 10% DT content was sufficient to negate the PEG effect in polymers containing iodinated tyrosine, whereas in non‐iodinated polymers, the PEG effect on cell attachment was reversed. Cross‐functional analysis of motility and proliferation revealed divergent substrate chemistry related cell response regimes. For instance, within the series of polymers containing both iodinated tyrosine and 10% of DT, increasing PEG levels lowered smooth muscle cell motility without a change in the rate of cell proliferation. In contrast, for non‐iodinated tyrosine and 10% of DT, increasing PEG levels increased cell proliferation significantly while reducing cell motility. Clearly, the polycarbonate polymer library offers a sensitive platform to modulate cell adhesion, proliferation, and motility responses, which, in turn, may have implications for controlling vascular remodeling in vivo. Additionally, our data suggests unique biorelevant properties following the incorporation of iodinated subunits in a polymeric biomaterial as a potential platform for X‐ray visible devices. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res, 2010
Mechanical and cell viability properties of crosslinked low‐ and high‐molecular weight poly(ethylene glycol) diacrylate blends
Authors: Mazzoccoli Jason P. , Feke Donald L. , Baskaran Harihara , Pintauro Peter N.
Published: July 2009

There is a strong need for tissue engineering scaffolds that are mechanically robust, exhibit good biocompatibility, and can be made from readily available materials. To this end, blends of commercially available poly(ethylene glycol) diacrylate (PEGDA) with molecular weights of 400 and 3400 were UV‐crosslinked at total polymer concentrations that varied systematically from 20 to 40 wt %. The compressive strength and cell viability were determined for each PEGDA mixture. The compressive modulus of the blends was maximized when the weight percent ratio PEGDA3400/400 was about 40/60, with the compressive strength reaching 1.7 MPa. Cell viability results with a LIVE/DEAD fluorescence assay show an average viability of ∼80% at a total PEGDA concentration of 20 wt % for all blends. Increasing the total polymer concentration increased the compressive modulus of a polymer, but adversely affected cell viability for all the PEGDA blend compositions. The blend composition affected the mechanical behavior of the discs, where a higher degree of crosslinking was achieved by increasing the concentration of shorter chained PEGDA400, whereas elasticity was gained by incorporating longer chained PEGDA3400 into the blends. These results can be exploited for use in tissue engineering applications, where a mechanically robust scaffold is advantageous. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res, 2010
Co‐activator activator (CoAA) prevents the transcriptional activity of Runt domain transcription factors
Authors: Li Xiaodong , Hoeppner Luke H. , Jensen Eric D. , Gopalakrishnan Rajaram , Westendorf Jennifer J.
Published: July 2009

Runx proteins are essential for a number of developmental processes and are aberrantly expressed in many human cancers. Runx factors bind DNA and co‐factors to activate or repress genes crucial for bone formation, hematopoiesis, and neuronal development. Co‐activator activator (CoAA) is a nuclear protein that regulates gene expression, RNA splicing and is overexpressed in many human tumors. In this study, we identified CoAA as a Runx2 binding protein. CoAA repressed Runx factor‐dependent activation of reporter genes in a histone deacetylase‐independent manner. CoAA also blocked Runx2‐mediated repression of the Axin2 promoter, a novel Runx target gene. The carboxy‐terminus of CoAA is essential for binding the Runt domains of Runx1 and Runx2. In electophoretic mobility shift assays, CoAA inhibited Runx2 interactions with DNA. These data indicate that CoAA is an inhibitor of Runx factors and can negate Runx factor regulation of gene expression. CoAA is expressed at high levels in human fetal osteoblasts and osteosarcoma cell lines. Suppression of CoAA expression by RNA interference reduced osteosarcoma cell viability in vitro, suggesting that it contributes to the proliferation and/or survival of osteoblast lineage cells. J. Cell. Biochem. 108: 378–387, 2009. © 2009 Wiley‐Liss, Inc.
Assessment of “grading” with Ki‐67 and c‐kit immunohistochemical expressions may be a helpful tool in management of patients with flat epithelial atypia (FEA) and columnar cell lesions (CCLs) on core breast biopsy
Authors: Tomasino Rosa M. , Morello Vincenza , Gullo Arianna , Pompei Giancarlo , Agnese Valentina , Russo Antonio , Rinaldi Gaetana
Published: July 2009

It is essential to reach a better understanding of “flat epithelial atypia/columnar cell lesions” (FEA/CCLs) in breast core biopsies. Our aim was to explore their biological nature, in order to predict the likelihood of an upgrade to carcinoma. “Cytological grading” has been specially focused, in view of its possible utility in the choice of management. One hundred thirty of a total of 900 cases core needle (CN)/vacuum‐assisted biopsies (VABs), with diagnoses of “hyperplasia” and “atypia” were retrospectively re‐evaluated. Pathological findings of further excision biopsies (FEBs) performed in 40/75 patients with follow‐up were compared with the previous diagnoses. In all cases, both Ki‐67 and c‐kit immunoreactivities were explored and compared with both normal breast tissues and subsequently documented cancers, with special reference to the hyperplastic FEA/CCLs, with “mild” atypia (FEA/CCHAm). Sixteen cases were re‐diagnosed as “usual ductal hyperplasia” (UDH), 60 as “columnar cell hyperplasia” (CCH), and 54 as FEA/CCHA, 30 of which FEA/CCHAm and 24 FEA/CCHAh (with high atypia). Significantly, the Ki‐67 index proved to be on the increase and c‐kit expression on the decrease in FEA/CCHA lesions, mainly in the FEA/CCHAh group and in the subsequently observed cancers, compared with either benign tissues or the FEA/CCH cases. It was also significant that most of the carcinomas were found in FEBs within the FEA/CCHAh group. In this study cytological grading, together with Ki‐67 and c‐kit indices, proved to be helpful in FEA/CCLs evaluation. With regard to FEA/CCHAm lesions, an adequate surveillance appears to be a more appropriate management tool than FEB, as a result of their biological nature and behavior. J. Cell. Physiol. 221: 343–349, 2009. © 2009 Wiley‐Liss, Inc.
Functional role of aquaglyceroporin 7 expression in the pancreatic beta‐cell line BRIN‐BD11
Authors: Delporte C. , Virreira M. , Crutzen R. , Louchami K. , Sener A. , Malaisse W.J. , Beauwens R.
Published: July 2009

Both mouse and rat pancreatic islet β‐cells were recently found to express aquaglyceroporin 7 (AQP7). In the present study, the expression and role of AQP7 in the function of BRIN‐BD11 cells were investigated. AQP7 mRNA and protein were detected by RT‐PCR and Western blot analysis, respectively. In an isoosmolar medium, the net uptake of [2‐3H]glycerol displayed an exponential time course reaching an equilibrium plateau value close to its extracellular concentration. Within 2 min of incubation in a hypotonic medium (caused by a 50 mM decrease in NaCl concentration), the [2‐3H]glycerol uptake averaged 143.2 ± 3.8% (n = 24; P < 0.001) of its control value in isotonic medium, declining thereafter consistently with previously demonstrated volume regulatory decrease. When isoosmolarity was restored by the addition of 100 mM urea to the hypotonic medium, [2‐3H]glycerol uptake remained higher (112.1 ± 2.8%, n = 24; P < 0.001) than its matched control under isotonic conditions, indicating rapid entry of urea and water. Insulin release by BRIN‐BD11 cells was 3 times higher in hypotonic than in isotonic medium. When glycerol (100 mM) or urea (100 mM) were incorporated in the hypotonic medium, the insulin release remained significantly higher than that found in the control isotonic medium, averaging respectively 120.2 ± 4.2 and 107.0 ± 3.8% of the paired value recorded in the hypotonic medium. These findings document the rapid entry of glycerol and urea in BRIN‐BD11 cells, likely mediated by AQP7. J. Cell. Physiol. 221: 424–429, 2009. © 2009 Wiley‐Liss, Inc.
Complex wear measurement on thin coatings by the cratering method
Authors: Bemporad E. , Comis E. , Sebastiani M. , Carassiti F. , Palumbo B.
Published: July 2009

Ball cratering and rotating wheel tests are useful techniques for abrasive wear resistance evaluation of thin coatings.

Nevertheless, such techniques involve significant experimental errors, coming from equipment deficiencies and changes in wear response depending on test parameters.

In case of rotating wheel test, common instrumental errors are: geometry‐induced errors (curved or non‐horizontal sample surface), alignment errors (misalignment between ball/wheel rotation axis and sample stage) and optical measurement errors.

In the present paper, errors due to crater dimension detection system (penetration depth or crater diameter) and equipment deficiencies (rotating axes misalignment and sample slope) were numerically analysed.

A general expression for volume calculation was obtained, considering axes misalignment and sample slope, and experimentally validated by wear tests on Ti/TiN CAE‐PVD coatings and profilometer abraded volumes measurement.

Results showed that axes misalignment and sample slope involve considerable errors in wear coefficient evaluation. However, errors can be corrected by the use of obtained expressions. Copyright © 2009 John Wiley & Sons, Ltd.
Polymerizable Well‐Defined Oligo(thiophene amide)s and their ROMP Block Copolymers
Authors: Hilf Stefan , Klos Johannes , Char Kookheon , Woo Heeje , Kilbinger Andreas F. M.
Published: July 2009

We report the synthesis of conjugated thiophene amide oligomers that constitute a new class of chromophores with potential for optoelectronic applications. The synthesis of defined norbornene‐substituted oligothiophene amides using conventional coupling chemistry is described. Their electronic properties depend on the degree of oligomerization as UV/Vis and fluorescence spectroscopy demonstrate. A significant red shift in the spectra upon an increase in the oligomer length evidences conjugation of the thiophene rings via the amide linkages. ROMP of the norbornene‐substituted oligomers gives homopolymers and block‐copolymers with a solubilizing second block. The amphiphilic character of the block copolymers is used to study micellization and bulk self‐organization.

magnified image
Numerical and in vivo validation of fast cine displacement‐encoded with stimulated echoes (DENSE) MRI for quantification of regional cardiac function
Authors: Feng Li , Donnino Robert , Babb James , Axel Leon , Kim Daniel
Published: July 2009

Quantitative assessment of regional cardiac function can improve the accuracy of detecting wall motion abnormalities due to heart disease. While recently developed fast cine displacement‐encoded with stimulated echoes (DENSE) MRI is a promising modality for the quantification of regional myocardial function, it has not been validated for clinical applications. The purpose of this study, therefore, was to validate the accuracy of fast cine DENSE MRI with numerical simulation and in vivo experiments. A numerical phantom was generated to model physiologically relevant deformation of the heart, and the accuracy of fast cine DENSE was evaluated against the numerical reference. For in vivo validation, 12 controls and 13 heart‐disease patients were imaged using both fast cine DENSE and myocardial tagged MRI. Numerical simulation demonstrated that the echo‐combination DENSE reconstruction method is relatively insensitive to clinically relevant resonance frequency offsets. The strain measurements by fast cine DENSE and the numerical reference were strongly correlated and in excellent agreement (mean difference = 0.00; 95% limits of agreement were 0.01 and −0.02). The strain measurements by fast cine DENSE and myocardial tagged MRI were strongly correlated (correlation coefficient = 0.92) and in good agreement (mean difference = 0.01; 95% limits of agreement were 0.07 and −0.04). Magn Reson Med, 2009. © 2009 Wiley‐Liss, Inc.
In vivo cytometry of antigen‐specific t cells using 19F MRI
Authors: Srinivas Mangala , Turner Michael S. , Janjic Jelena M. , Morel Penelope A. , Laidlaw David H. , Ahrens Eric T.
Published: July 2009

Noninvasive methods to image the trafficking of phenotypically defined immune cells are paramount as we attempt to understand adaptive immunity. A 19F MRI‐based methodology for tracking and quantifying cells of a defined phenotype is presented. These methods were applied to a murine inflammation model using antigen‐specific T cells. The T cells that were intracellularly labeled ex vivo with a perfluoropolyether (PFPE) nanoemulsion and cells were transferred to a host receiving a localized inoculation of antigen. Longitudinal 19F MRI over 21 days revealed a dynamic accumulation and clearance of T cells in the lymph node (LN) draining the antigen. The apparent T‐cell numbers were calculated in the LN from the time‐lapse 19F MRI data. The effect of in vivo T‐cell division on the 19F MRI cell quantification accuracy was investigated using fluorescence assays. Overall, in vivo cytometry using PFPE labeling and 19F MRI is broadly applicable to studies of whole‐body cell biodistribution. Magn Reson Med, 2009. © 2009 Wiley‐Liss, Inc.