bluuebunny/crossref_metadata_2025 huggingface dataset:
ChemInform Abstract: Flavonoid Constituents from the Roots of Acanthopanax brachypus
Authors: Hu Hao‐bin , Zhu Ji‐hua
Published: July 2011

isolation and characterization of the two new natural products (I) and (II) along with eleven known flavonoids
ChemInform Abstract: Synthesis of Demethoxy‐Lycoraminone.
Authors: Herke Klara , Hazai Laszlo , Dubrovay Zsofia , Hada Viktor , Santa Zsuzsanna , Szantay Csaba Jr. , Kalaus Gyoergy , Szantay Csaba
Published: July 2011

It is important that the reduction with lithium aluminum hydride is conducted prior to the cyclization step.
ChemInform Abstract: Synthetic Chemistry of Nonstoichiometric Compounds
Authors: Zhang Jilin , Hong Guangyan
Published: July 2011

Review: 11 refs.
ChemInform Abstract: CVD and Its Related Theories in Inorganic Synthesis and Materials Preparations
Authors: Wang Ji‐Tao
Published: July 2011

Review: 52 refs.
ChemInform Abstract: Synthesis and Purification at Low Temperature
Authors: Pang Wenqin
Published: July 2011

Review: 55 refs.
ChemInform Abstract: Magnetic and Magnetoelectric Excitations in Multiferroic Manganites
Authors: Shuvaev A. M. , Mukhin A. A. , Pimenov A.
Published: July 2011

Review: 49 refs.
ChemInform Abstract: Self‐Assembled Nanometer‐Scale Magnetic Networks on Surfaces: Fundamental Interactions and Functional Properties
Authors: Carbone Carlo , Gardonio Sandra , Moras Paolo , Lounis Samir , Heide Marcus , Bihlmayer Gustav , Atodiresei Nicolae , Dederichs Peter Heinz , Bluegel Stefan , Vlaic Sergio , et al. et al.
Published: July 2011

Review: 86 refs.
ChemInform Abstract: Intramolecular d10—d10 Ineractions in Heterometallic Clusters of the Transition Metals
Authors: Sculfort Sabrina , Braunstein Pierre
Published: July 2011

Review: 188 refs.
ChemInform Abstract: Metal‐Catalyzed Cascade Reactions of Ethynyl‐Substituted Naphthalenes: Synthesis of Polycyclic Arenes
Authors: Wu Tsun‐Cheng , Wu Yao‐Ting
Published: July 2011

Review: 32 refs.
ChemInform Abstract: Continuous Flow Organometallic Catalysis: New Wind in Old Sails
Authors: Hintermair Ulrich , Francio Giancarlo , Leitner Walter
Published: July 2011

Review: 91 refs.
ChemInform Abstract: Oxidation Reactions with NHC‐Metal Complexes
Authors: Podhajsky Susanne M. , Sigman Matthew S.
Published: July 2011

Review: 62 refs.
ChemInform Abstract: NHC—Cobalt, —Rhodium and —Iridium Complexes in Catalysis
Authors: Cesar Vincent , Gade Lutz H. , Bellemin‐Laponnaz Stephane
Published: July 2011

Review: 108 refs.
ChemInform Abstract: Synthesis of DNA‐Interactive Pyrrolo[2,1‐c][1,4]benzodiazepines (PBDs)
Authors: Antonow Dyeison , Thurston David E.
Published: July 2011

Review: 225 refs.
ChemInform Abstract: N‐Heterocyclic Carbenes: Versatile Reagents for Nickel‐Catalyzed Coupling Reactions
Authors: Gu Shaojin , Ni Peng , Chen Wanzhi
Published: July 2011

Review: 88 refs.
ChemInform Abstract: Thiazole: A Valuable Insight into Recent Advances, Synthesis and Biological Activities
Authors: Zagade Amrita A. , Senthilkumar G. P.
Published: July 2011

Review: 25 refs.
ChemInform Abstract: Development and Applications of an Oxazole‐Forming Reaction
Authors: Zhang Jianmin , Coqueron Pierre‐Yves , Ciufolini Marco A.
Published: July 2011

Review: 163 refs.
ChemInform Abstract: Recent Developments in the Total Synthesis of Fungicidal Natural Products — A Crop Protection Perspective
Authors: Nising Carl F. , Hillebrand Stefan , Rodefeld Lars
Published: July 2011

Review: 40 refs.
ChemInform Abstract: Versatilities of Calix[4]pyrrole Based Anion Receptors
Authors: Lee Chang Hee
Published: July 2011

Review: synthesis and anion binding properties of calixpyrroles; 73 refs.
ChemInform Abstract: Expanded Porphyrins and Aromaticity
Authors: Osuka Atsuhiro , Saito Shohei
Published: July 2011

Review: 64 refs.
ChemInform Abstract: Greener Solvents for Ruthenium and Palladium‐Catalyzed Aromatic C—H Bond Functionalization
Authors: Fischmeister Cedric , Doucet Henri
Published: July 2011

Review: 160 refs.
ChemInform Abstract: A Critical Assessment of the Greenness and Energy Efficiency of Microwave‐Assisted Organic Synthesis
Authors: Moseley Jonathan D. , Kappe C. Oliver
Published: July 2011

Review: 141 refs.
ChemInform Abstract: Spectroscopy of Moelcular Junctions
Authors: Shamai Tamar , Selzer Yoram
Published: July 2011

Review: 56 refs.
ChemInform Abstract: Charge Transport in High Mobility Molecular Semiconductors: Classical Models and New Theories
Authors: Troisi Alessandro
Published: July 2011

Review: 53 refs.
ChemInform Abstract: Chemomechanics: Chemical Kinetics for Multiscale Phenomena
Authors: Huang Zhen , Boulatov Roman
Published: July 2011

Review: 102 refs.
ChemInform Abstract: Iron, Cysteine and Parkinson′s Disease.
Authors: Jameson Guy N. L.
Published: July 2011

Review: 52 refs.
ChemInform Abstract: The Chemical Process of Oxidative Stress by Copper(II) and Iron(III) Ions in Several Neurodegenerative Disorders
Authors: Nishida Yuzo
Published: July 2011

Review: 79 refs.
ChemInform Abstract: Roles of Histamine in the Exacerbated Allergic Dermatitis
Authors: Hirasawa Noriyasu , Ohuchi Kazuo
Published: July 2011

Review: 20 refs.
ChemInform Abstract: Lithium‐Doped Hybrid Polymer Electrolytes
Authors: de Zea Bermudez V. , Silva M. M.
Published: July 2011

Review: 127 refs.
An efficient graphics processing unit‐based parallel algorithm for pricing multi‐asset American options
Authors: Dang Duy Minh , Christara Christina C. , Jackson Kenneth R.
Published: July 2011

We develop highly efficient parallel PDE‐based pricing methods on graphics processing units (GPUs) for multi‐asset American options. Our pricing approach is built upon a combination of a discrete penalty approach for the linear complementarity problem arising because of the free boundary and a GPU‐based parallel alternating direction implicit approximate factorization technique with finite differences on uniform grids for the solution of the linear algebraic system arising from each penalty iteration. A timestep size selector implemented efficiently on GPUs is used to further increase the efficiency of the methods. We demonstrate the efficiency and accuracy of the parallel numerical methods by pricing American options written on three assets. Copyright © 2011 John Wiley & Sons, Ltd.
The pharmacology and toxicology of the synthetic cathinone mephedrone (4‐methylmethcathinone)
Authors: Dargan Paul I. , Sedefov Roumen , Gallegos Ana , Wood David M.
Published: July 2011

Mephedrone (4‐methylmethcathinone) is a synthetic cathinone that is used as a recreational drug. It has been available since 2007 but its availability and use increased significantly during 2009 and 2010. In this review article we will summarize the available literature on the sources, availability, and prevalence of the use of mephedrone. We will also discuss the pharmacology of mephedrone, the patterns of acute toxicity associated with its use, the reports of fatalities associated with its use, and the potential for mephedrone dependence. Copyright © 2011 John Wiley & Sons, Ltd.
Cathinone derivatives: A review of their chemistry, pharmacology and toxicology
Authors: Kelly John P.
Published: July 2011

The purpose of this review is to evaluate what is currently known about the pharmacology of cathinone derivatives. Cathinone is the principal active constituent of khat responsible for the stimulant effects that have led khat to be known as a ‘natural amphetamine’. Synthetic derivatives have been abused for their amphetamine‐like stimulant effects, most notably methylone, methcathinone (ephedrone), and 4‐methlymethcathinone (mephedrone). To date, cathinone and methcathinone have been studied most, demonstrating amphetamine‐like effects in a range of in vitro and in vivo investigations, albeit less potently than amphetamines. In humans, cathinone derivatives are usually administered orally, and in some cases by insufflation. Methcathinone has a longer history of abuse, being produced from readily available starting materials, and administered by injection. Mephedrone has become the best publicised cathinone derivative, amid considerable media and public concern about its legal status, its ready availability, and reports of serious toxicity and deaths following its use. As a consequence, there has been a clampdown on cathinone derivatives, dramatically changing their legal status in a number of countries. However, little objective evidence‐based comparative experiments have been conducted to date between these compounds and their related amphetamines in order to make clear risk judgements. Such assessments have largely been predictive in nature, based on their structural similarity to amphetamines. It can be assumed that, despite their illegal status, cathinone‐related compounds will continue to be prevalent drugs of abuse for the foreseeable future. Copyright © 2011 John Wiley & Sons, Ltd.
Some new psychoactive substances: Precursor chemicals and synthesis‐driven end‐products
Authors: Collins Michael
Published: July 2011

This paper describes some of the new classes of ‘designer drugs’ being encountered today by forensic scientists and law enforcement agencies in Europe, the United States, and Australia. In particular, it concentrates on new cathinone derivatives, the tryptamines, new‐generation phenethylamines, and some of the synthetic cannabinoids. The synthetic approaches towards many of these designer drugs including a discussion of the chemical precursors used in the syntheses are presented. Many of today's so‐called designer drugs exist as a result of legitimate research into medical conditions and the natural product chemistry. A link between synthetic approaches published in the open scientific and medical literature and the exploitation of this research by clandestine manufacture of drugs for illicit purposes is drawn. Copyright © 2011 John Wiley & Sons, Ltd.
Developmental expression of the fermitin/kindlin gene family in Xenopus laevis embryos
Authors: Canning Claire A. , Chan Jessica Sze Ki , Common John E. A. , Lane E. Birgitte , Jones C. Michael
Published: July 2011

Fermitin genes are highly conserved and encode cytocortex proteins that mediate integrin signalling. Fermitin 1 (Kindlin1) is implicated in Kindler syndrome, a human skin blistering disorder. We report the isolation of the three Fermitin orthologs from Xenopus laevis embryos and describe their developmental expression patterns. Fermitin 1 is expressed in the skin, otic and olfactory placodes, pharyngeal arches, pronephric duct, and heart. Fermitin 2 is restricted to the somites and neural crest. Fermitin 3 is expressed in the notochord, central nervous system, cement gland, ventral blood islands, vitelline veins, and myeloid cells. Our findings are consistent with the view that Fermitin 1 is generally expressed in the skin, Fermitin 2 in muscle, and Fermitin 3 in hematopoietic lineages. Moreover, we describe novel sites of Fermitin gene expression that extend our knowledge of this family. Our data provide a basis for further functional analysis of the Fermitin family in Xenopus laevis. Developmental Dynamics 240:1958–1963, 2011. © 2011 Wiley‐Liss, Inc.
Cell biological regulation of division fate in vertebrate neuroepithelial cells
Authors: Willardsen Minde I. , Link Brian A.
Published: July 2011

The developing nervous system derives from neuroepithelial progenitor cells that divide to generate all of the mature neuronal types. For the proper complement of cell types to form, the progenitors must produce postmitotic cells, yet also replenish the progenitor pool. Progenitor divisions can be classified into three general types: symmetric proliferative (producing two progenitors), asymmetric neurogenic (producing one progenitor and one postmitotic cell), and symmetric neurogenic (producing two postmitotic cells). The appropriate ratios for these modes of cell division require intrinsic polarity, which is one of the characteristics that define neuroepithelial progenitor cells. The type of division an individual progenitor undergoes can be influenced by cellular features, or behaviors, which are heterogeneous within the population of progenitors. Here we review three key cellular parameters, asymmetric inheritance, cell cycle kinetics, and interkinetic nuclear migration, and the possible mechanisms for how these features influence progenitor fates. Developmental Dynamics 240:1865–1879, 2011. © 2011 Wiley‐Liss, Inc.
V‐ATPase‐dependent ectodermal voltage and ph regionalization are required for craniofacial morphogenesis
Authors: Vandenberg Laura N. , Morrie Ryan D. , Adams Dany Spencer
Published: July 2011

Using voltage and pH reporter dyes, we have discovered a never‐before‐seen regionalization of the Xenopus ectoderm, with cell subpopulations delimited by different membrane voltage and pH. We distinguished three courses of bioelectrical activity. Course I is a wave of hyperpolarization that travels across the gastrula. Course II comprises the appearance of patterns that match shape changes and gene expression domains of the developing face; hyperpolarization marks folding epithelium and both hyperpolarized and depolarized regions overlap domains of head patterning genes. In Course III, localized regions of hyperpolarization form at various positions, expand, and disappear. Inhibiting H+‐transport by the H+‐V‐ATPase causes abnormalities in: (1) the morphology of craniofacial structures; (2) Course II voltage patterns; and (3) patterns of sox9, pax8, slug, mitf, xfz3, otx2, and pax6. We conclude that this bioelectric signal has a role in development of the face. Thus, it exemplifies an important, under‐studied mechanism of developmental regulation. Developmental Dynamics 240:1889–1904, 2011. © 2011 Wiley‐Liss, Inc.
Analysis of Cdh22 expression and function in the developing mouse brain
Authors: Saarimäki‐Vire Jonna , Alitalo Annamari , Partanen Juha
Published: July 2011

Classical cadherins are important cell adhesion molecules specifying and separating brain nuclei and developmental compartments.Cadherin‐22(Cdh22) belongs to type II subfamily of classical cadherins, and is expressed at the midbrain‐hindbrain boundary during early embryogenesis. InFgfr1mutant mouse embryos, which have a disturbed midbrain‐hindbrain border,Cdh22is down‐regulated. Here, we studied expression ofCdh22in developing mouse brain in more detail and compared it to expression of related family members. This revealed both complementary and overlapping patterns ofCdh22, Cdh11, Cdh8, andCdh6expression in distinct regions of the forebrain and midbrain. We used a mutated allele ofCdh22to study its function in brain development. Loss of Cdh22 caused reduced postnatal viability. Despite strongCdh22expression in the developing brain, we did not observe defects in compartmentalization or abnormalities in the midbrain and forebrain nuclei inCdh22mutants. This may be explained by functional redundancy between type II cadherins. Developmental Dynamics 240:1989–2001, 2011. © 2011 Wiley‐Liss, Inc.
Planar cell movements and oriented cell division during early primitive streak formation in the mammalian embryo
Authors: Halacheva Viktoriya , Fuchs Mathias , Dönitz Jürgen , Reupke Tobias , Püschel Bernd , Viebahn Christoph
Published: July 2011

Formation of the mammalian primitive streak appears to rely on cell proliferation to a minor extent only, but compensating cell movements have not yet been directly observed. This study analyses individual cell migration and proliferation simultaneously, using multiphoton and differential interference contrast time‐lapse microscopy of late pregastrulation rabbit blastocysts. Epiblast cells in the posterior gastrula extension area accumulated medially and displayed complex planar movements including U‐turns and a novel type of processional cell movement. In the same area metaphase plates tended to be aligned parallel to the anterior–posterior axis, and statistical analysis showed that rotations of metaphase plates causing preferred orientation were near‐complete 8 min before anaphase onset; in some cases, rotations were strikingly rapid, achieving up to 45° per min. The mammalian primitive streak appears to be formed initially with its typically minimal anteroposterior elongation by a combination of oriented cell divisions with dedicated planar cell movements. Developmental Dynamics 240:1905–1916, 2011. © 2011 Wiley‐Liss, Inc.
Primer and interviews: Promises and realities of induced pluripotent stem cells
Authors: Kiefer Julie C.
Published: July 2011

In 2006, Yamanaka's group announced they had discovered the proverbial “fountain of youth” for human cells, forever changing the field of stem cell research. After misexpressing within them a cocktail of four genes, adult somatic cells revert into an embryonic stem cell (ESC)‐like state. These so‐called induced pluripotent stem cells (iPSCs) can differentiate into a wide variety of cell types, seemingly bypassing the need for politically charged ESCs. However, iPSCs differ from ESCs in potentially deleterious ways, precluding their use in regenerative medicine. In this primer and adjoining discussion with iPSC biologists William Lowry, PhD, and Clive Svendsen, PhD, we explore these issues as well how iPSCs promise to contribute to the understanding of developmental biology and the etiology, and treatment, of human diseases. Developmental Dynamics 240:2034–2041, 2011. © 2011 Wiley‐Liss, Inc.
Zebrafish nephrogenesis involves dynamic spatiotemporal expression changes in renal progenitors and essential signals from retinoic acid and irx3b
Authors: Wingert Rebecca A. , Davidson Alan J.
Published: July 2011

Kidney nephrons are composed of proximal and distal tubule segments that perform unique roles in excretion. The developmental pathways that establish nephron segment identities from renal progenitors are poorly understood. Here, we used the zebrafish pronephros to study nephron segmentation. We found that zebrafish nephron progenitors undergo elaborate spatiotemporal expression changes of many genes before adopting a segment fate. Initially, two domains of nephron progenitors are established, then are subdivided and demarcate individual nephron segments. Using genetic and chemical genetic models of retinoic acid (RA) deficiency, we discovered that RA modulates rostral progenitor formation. To delineate downstream pathways, we knocked down the irx3b transcription factor and found it regulates proximal tubule segment size and distal segment differentiation. Our results suggest a model whereby RA patterns the early field of nephron progenitors, with subsequent factors like irx3b acting to refine later progenitor subdomains and ensure activation of segment‐specific gene programs. Developmental Dynamics 240:2011–2027, 2011. © 2011 Wiley‐Liss, Inc.
Quantitative three‐dimensional imaging of live avian embryonic morphogenesis via micro‐computed tomography
Authors: Henning Alyssa L. , Jiang Michael X. , Yalcin Huseyin C. , Butcher Jonathan T.
Published: July 2011

Many clinically relevant congenital malformations arise during mid to late embryonic stages. This period is challenging to image quantitatively in live embryos, necessitating the use of multiple specimens with increased experimental variability. Here we establish X‐ray and blood‐pool computed tomography (CT) contrast agent toxicity and teratogenesis thresholds for 3D Micro‐CT imaging of live avian embryos. Day 4 chick embryos micro‐injected with Visipaque™ (VP) developed for an additional 6 days without defect. X‐ray radiation up to 798 mGy was nontoxic. Peak average contrast of 1,060 HU occurred within 1 hr of imaging at 50 μm resolution. VP‐enhanced contrast persisted past 24 hr with delayed accumulation in the allantois. Regional volumes of VP‐injected embryos were statistically identical to those of fixed embryos perfused with osmium tetroxide. We further quantified longitudinal volumetric morphogenesis of the allantois over 30 hr. These results demonstrate the safety and efficacy of contrast enhanced quantitative micro‐CT imaging for live embryos. Developmental Dynamics 240:1949–1957, 2011. © 2011 Wiley‐Liss, Inc.
A transgenic zebrafish model of targeted oocyte ablation and de novo oogenesis
Authors: White Yvonne A. R. , Woods Dori C. , Wood Antony W.
Published: July 2011

We describe here a novel transgenic zebrafish, Tg(zpc:G4VP16/UAS:nfsB‐mCherry) that effectively demonstrates the targeted oocyte ablation in the adult zebrafish ovary. This transgenic line expresses bacterial nitroreductase enzyme (nfsB) under the control of the oocyte‐specific zona pellucida C (zpc) gene promoter. Adult transgenic females exposed to the prodrug metronidazole demonstrated near‐complete ablation of growing oocytes, resulting in ovarian degeneration and complete cessation of reproductive function. Within 4 weeks of prodrug removal, treated fish demonstrated complete anatomical regeneration of the ovary and, within 7 weeks, ovarian function (fertility) was fully restored. Together, these results demonstrate functional renewal of the oocyte pool in the adult zebrafish ovary. Accordingly, this transgenic zebrafish model system provides a novel means to investigate ovarian growth dynamics in a genetically tractable vertebrate, and may be useful for evaluating signaling interactions that regulate gonadal development processes such as de novo oogenesis. Developmental Dynamics 240:1929–1937, 2011. © 2011 Wiley‐Liss, Inc.
Expression of metanephric nephron‐patterning genes in differentiating mesonephric tubules
Authors: Georgas K.M. , Chiu H.S. , Lesieur E. , Rumballe B.A. , Little Melissa H.
Published: July 2011

Schematic illustrating the murine urogenital tract at 13.5 dpc. The early tubules of the metanephros (kidney) and mesonephric tubules of the mesonephros are highlighted in blue. Below are examples of gene expression in the early tubules of the kidney (Lhx1, centre) and in the mesonephric tubules of the male mesonephroi (Gpd1) detected using wholemount in situ hybridization. From Georgas et al., Developmental Dynamics 240:1600–1612, 2011.
DNA Cleavage by Structurally Characterized Dinuclear Copper(II) Complexes Based on Triazine
Authors: Massoud Salah S. , Louka Febee R. , Xu Wu , Perkins Richard S. , Vicente Ramon , Albering Jörg H. , Mautner Franz A.
Published: July 2011

The reaction of 2‐chloro‐4,6‐bis(di‐2‐picolylamino)‐1,3,5‐triazine (bdpaTCl) with copper(II) perchlorate and copper(II) chloride afforded two dinuclear complexes [Cu2(μ‐bdpaTCl)(μ‐OH)2(H2O)0.5(ClO4)0.5](ClO4)1.5·(H2O)1.5 (1) and [Cu2(μ‐bdpaTCl)Cl4]·2CH3OH (2), respectively. These complexes were characterized by IR, UV/Vis, and EPR spectroscopy, single‐crystal X‐ray crystallography, and temperature dependence magnetic susceptibility measurements (2–300 K) as well as by electrochemical and molar conductivity measurements. In 1, each of the three N‐donor atoms of the binucleating bdpaTCl ligand coordinate to CuII ions, which are further bridged by two OH– anions in a distorted five‐coordinate geometry. In addition, each CuII ion forms a Cu–O semicoordinate bond with an aqua ligand or perchlorato anion. The Cu···Cu distance across the hydroxido bridges is 2.9698(11) Å. In 2, the bdpaTCl ligand acts as bis‐tridentate ligand connecting the two CuII ions, and the five‐coordinate geometry around each copper center is achieved by two terminal chloro ligands. Magnetic measurements revealed strong antiferromagnetic coupling in 1 (J = –311.2 cm–1) and very weak coupling in 2 (J = –2.4 cm–1). DNA cleavage by these two complexes has been investigated (pH = 7.0, 37 °C). Although the bridged dihydroxido complex 1 did not show any detectable cleavage for DNA, significant cleavage was observed with the tetrachloro complex 2. Under pseudo‐Michaelis–Menten kinetic conditions, the kinetic parameters kcat = 2.53 × 10–5 s–1 and KM = 1.44 × 10–4 M were determined for 2. The kcat value corresponds to a 2.5 × 106 fold rate enhancement over noncatalyzed DNA. Electrophoretic experiments conducted in the presence and absence of oxidative scavengers DMSO, KI, and NaN3, and radical promoter H2O2 provide evidence for the oxidative cleavage of DNA by hydroxy radicals and hydrogen peroxide species.
Bone mineral imaged in vivo by 31P solid state MRI of human wrists
Authors: Wu Yaotang , Reese Timothy G. , Cao Haihui , Hrovat Mirko I. , Toddes Steven P. , Lemdiasov Rostislav A. , Ackerman Jerome L.
Published: July 2011

Purpose:

To implement solid state 31P MRI (31P SMRI) in a clinical scanner to visualize bone mineral.

Materials and Methods:

Wrists of seven healthy volunteers were scanned. A quadrature wrist 31P transmit/receive coil provided strong B1 and good signal‐to‐noise ratio (SNR). A 1H‐31P frequency converter was constructed to enable detection of the 31P signal by means of the 1H channel. Data points lost in the receiver dead time were recovered by a second acquisition with longer dwell time and lower gradient strength.

Results:

Three‐dimensional 31P images, showing only bone mineral of the wrist, were obtained with a clinical 3 Tesla (T) scanner. In the best overall case an image with isotropic resolution of ∼5.1 mm and SNR of 30 was obtained in 37 min. 31P NMR properties (resonance line width 2 kHz and T1 17–19 s) of in vivo human bone mineral were measured.

Conclusion:

In vivo 31P SMRI visualization of human wrist bone mineral with a clinical MR scanner is feasible with suitable modifications to circumvent the scanners' limitations in reception of short‐T2 signals. Frequency conversion methodology is useful for implementing 31P SMRI measurements on scanners which do not have multinuclear capability or for which the multinuclear receiver dead time is excessive. J. Magn. Reson. Imaging 2011;. © 2011 Wiley‐Liss, Inc.
Monitoring neoadjuvant chemotherapy in breast cancer patients: Improved MR assessment at 3 T?
Authors: Heldahl Mariann G. , Lundgren Steinar , Jensen Line R. , Gribbestad Ingrid S. , Bathen Tone F.
Published: July 2011

Purpose:

To investigate possible improvements in predicting the response to neoadjuvant chemotherapy (NAC) at 3 T for locally advanced breast cancer (LABC).

Materials and Methods:

Dynamic contrast‐enhanced magnetic resonance (DCE‐MR) images acquired before and during NAC were retrospectively analyzed in 85 patients. Tumor volume and diameter, three volumes based on the shape of the enhancement curve, relative signal intensity, area under the curve, and the signal‐to‐noise ratio were extracted. Differences between responders and nonresponders at the same and between MR timepoints during treatment were evaluated.

Results:

A higher signal‐to‐noise ratio was observed on 3 T images compared to 1.5 T, and 3 T revealed more significant findings related to response compared to 1.5 T. The DCE‐MRI‐derived volume parameters were the earliest predictors of response at both 1.5 and 3 T.

Conclusion:

Our results show that 3 T provides an improved assessment of the response to NAC in LABC patients, where the MR determined tumor volume reduction before the second cycle of NAC was the strongest and earliest predictor of a response. J. Magn. Reson. Imaging 2011;. © 2011 Wiley‐Liss, Inc.
Ventilation/perfusion imaging of the lung using ultra‐short echo time (UTE) MRI in an animal model of pulmonary embolism
Authors: Togao Osamu , Ohno Yoshiharu , Dimitrov Ivan , Hsia Connie C. , Takahashi Masaya
Published: July 2011

Purpose:

To test the feasibility of ultra‐short echo time (UTE) MRI for assessment of regional pulmonary ventilation/perfusion in a standard 3 Tesla clinical MRI system.

Materials and Methods:

MRI of the lungs was conducted with an optimized three‐dimensional UTE sequence in normal rats and in a rat model of pulmonary embolism (PE) induced by a blood clot. Changes in signal intensities (SIs) due to inhalation of molecular oxygen or intravenous (i.v.) injection of Gd, which represents the distribution of ventilation and perfusion, respectively, were assessed in the lung parenchyma.

Results:

The UTE MRI with a TE of 100 μs could detect and map the changes in SI of the lung parenchyma due to the inhalation of 100% oxygen or i.v. injection of Gd in normal rats. Reduced T1 resulting from oxygen inhalation was also quantified. These changes were not observed on the images that were obtained simultaneously with a conventional range of TE (2.3 ms). Furthermore, the method could delineate the embolized lesions where the lung ventilation and perfusion were mismatched in a rat model with PE.

Conclusion:

These results show the feasibility and diagnostic potential of UTE MRI for the assessment of pulmonary ventilation and perfusion which is essential for the evaluation of a variety of lung diseases. J. Magn. Reson. Imaging 2011;. © 2011 Wiley‐Liss, Inc.
Age‐related and regional changes of aortic stiffness in the marfan syndrome: Assessment with velocity‐encoded MRI
Authors: Westenberg Jos J.M. , Scholte Arthur J.H.A. , Vaskova Zuzana , van der Geest Rob J. , Groenink Maarten , Labadie Gerda , van den Boogaard Pieter J. , Radonic Teodora , Hilhorst‐Hofstee Yvonne , Mulder Barbara J.M. , Kroft Lucia J.M. , Reiber Johan H.C. , de Roos Albert
Published: July 2011

Purpose:

To study age‐related change in aortic stiffness in patients with Marfan syndrome (MFS) versus healthy volunteers using velocity‐encoded (VE) MRI.

Materials and Methods:

Twenty‐five MFS patients (age range, 18–63 years; mean age 36 ± 14 years, 13 men) and 25 age‐/gender‐matched healthy volunteers were examined with VE‐MRI. Aortic stiffness was expressed by pulse wave velocity (PWV), assessed in the proximal and distal part of the aorta and in the total aorta. PWV was compared between patients and volunteers and age‐relation was determined by linear regression.

Results:

PWV was significantly higher in all parts of the aorta in patients when compared with healthy volunteers (proximal aorta 5.7 ± 1.5 m/s versus 4.8 ± 0.9 m/s, distal aorta 6.4 ± 2.4 m/s versus 5.0 ± 1.2 m/s and total aorta 5.9 ± 1.7 m/s versus 4.9 ± 1.1 m/s, all P < 0.004). PWV correlated significantly with age (Pearson R between 0.45 and 0.94). Only in the proximal aorta, the increase in PWV with age was significantly higher in patients (7 ± 2 cm/s increase with age) than in volunteers (3 ± 1 cm/s increase, P = 0.03); in the distal or total aorta, the increase in PWV with age was not different between patients and volunteers.

Conclusion:

Velocity‐encoded MRI detects more pronounced age‐related aortic stiffening in the proximal aorta in MFS patients versus healthy volunteers, suggesting more severe wall disease in MFS. J. Magn. Reson. Imaging 2011;. © 2011 Wiley‐Liss, Inc.
Quantitative contrast‐enhanced first‐pass cardiac perfusion MRI at 3 tesla with accurate arterial input function and myocardial wall enhancement
Authors: Breton Elodie , Kim Daniel , Chung Sohae , Axel Leon
Published: July 2011

Purpose:

To develop, and validate in vivo, a robust quantitative first‐pass perfusion cardiovascular MR (CMR) method with accurate arterial input function (AIF) and myocardial wall enhancement.

Materials and Methods:

A saturation‐recovery (SR) pulse sequence was modified to sequentially acquire multiple slices after a single nonselective saturation pulse at 3 Tesla. In each heartbeat, an AIF image is acquired in the aortic root with a short time delay (TD) (50 ms), followed by the acquisition of myocardial images with longer TD values (∼150–400 ms). Longitudinal relaxation rates (R1 = 1/T1) were calculated using an ideal saturation recovery equation based on the Bloch equation, and corresponding gadolinium contrast concentrations were calculated assuming fast water exchange condition. The proposed method was validated against a reference multi‐point SR method by comparing their respective R1 measurements in the blood and left ventricular myocardium, before and at multiple time‐points following contrast injections, in 7 volunteers.

Results:

R1 measurements with the proposed method and reference multi‐point method were strongly correlated (r > 0.88, P < 10−5) and in good agreement (mean difference ±1.96 standard deviation 0.131 ± 0.317 / 0.018 ± 0.140 s−1 for blood/myocardium, respectively).

Conclusion:

The proposed quantitative first‐pass perfusion CMR method measured accurate R1 values for quantification of AIF and myocardial wall contrast agent concentrations in 3 cardiac short‐axis slices, in a total acquisition time of 523 ms per heartbeat. J. Magn. Reson. Imaging 2011;. © 2011 Wiley‐Liss, Inc.
Evaluation of axillary lymph nodes by diffusion‐weighted MRI using ultrasmall superparamagnetic iron oxide in patients with breast cancer: Initial clinical experience
Authors: Nakai Go , Matsuki Mitsuru , Harada Tomoaki , Tanigawa Nobuhiko , Yamada Takashi , Barentsz Jelle , Narumi Yoshifumi
Published: July 2011

Purpose:

To investigate the diagnostic performance and clinical feasibility of diffusion‐weighted magnetic resonance imaging (MRI) using ultrasmall superparamagnetic iron oxide (USPIO) in the evaluation of axillary lymph nodes (ALNs) in patients with breast cancer.

Materials and Methods:

Sixteen patients with known breast cancer underwent 1.5 T MRI. Axial diffusion‐weighted images (DWIs) and conventional T1‐ and T2*‐weighted images (CIs) were acquired before and 24–36 hours after intravenous administration of USPIO. Detection of ALNs was evaluated on DWIs in comparison with CIs. The apparent diffusion coefficient values (ADCvs) of the nonmetastatic and metastatic nodes in precontrast DWIs were determined. The diagnostic performance of DWI using USPIO was compared with that of CIs using USPIO with pathological correlation.

Results:

Out of a total of 286 ALNs, 216/286 (76%) nodes were detected on DWIs and 238/286 (83%) on CIs. The differences in the ADCvs between metastatic and nonmetastatic nodes were not significant (P = 0.06). Sensitivity of CIs and DWIs using USPIO were respectively 70% and 83%, specificity 98% and 98%, and overall accuracy 93% and 95%.

Conclusion:

Although the detection on DWIs of ALNs in patients with breast cancer was inferior compared to CIs, the sensitivity and accuracy of DWIs using USPIO were superior in the diagnosis of ALNs metastasis. J. Magn. Reson. Imaging 2011;. © 2011 Wiley‐Liss, Inc.
Quantification of renal perfusion: Comparison of arterial spin labeling and dynamic contrast‐enhanced MRI
Authors: Winter Jeff D. , St. Lawrence Keith S. , Cheng Hai‐Ling Margaret
Published: July 2011

Purpose:

To provide the first comparison of absolute renal perfusion obtained by arterial spin labeling (ASL) and separable compartment modeling of dynamic contrast‐enhanced (DCE) magnetic resonance imaging (MRI). Moreover, we provide the first application of the dual bolus approach to quantitative DCE‐MRI perfusion measurements in the kidney.

Materials and Methods:

Consecutive ASL and DCE‐MRI acquisitions were performed on six rabbits on a 1.5 T MRI system. Gadolinium (Gd)‐DTPA was administered in two separate injections to decouple measurement of the arterial input function and tissue uptake curves. For DCE perfusion, pixel‐wise and mean cortex region‐of‐interest tissue curves were fit to a separable compartment model.

Results:

Absolute renal cortex perfusion estimates obtained by DCE and ASL were in close agreement: 3.28 ± 0.59 mL/g/min (ASL), 2.98 ± 0.60 mL/g/min (DCE), and 3.57 ± 0.96 mL/g/min (pixel‐wise DCE). Renal medulla perfusion was 1.53 ± 0.35 mL/g/min (ASL) but was not adequately described by the separable compartment model.

Conclusion:

ASL and DCE‐MRI provided similar measures of absolute perfusion in the renal cortex, offering both noncontrast and contrast‐based alternatives to improve current renal MRI assessment of kidney function. J. Magn. Reson. Imaging 2011;. © 2011 Wiley‐Liss, Inc.
Vegetation history of the penultimate glacial period (Marine isotope stage 6) at Ioannina, north‐west Greece
Authors: Roucoux K. H. , Tzedakis P. C. , Lawson I. T. , Margari V.
Published: July 2011

The vegetational history of the penultimate glacial period, Marine Isotope Stage (MIS) 6 (c. 185–135 ka), has remained relatively unexplored. Here we present a new record from the Ioannina basin, north‐west Greece, which constitutes the highest‐resolution terrestrial pollen record for this interval produced to date. It shows that the vegetation history of MIS 6 in this region can be divided into two parts: an early period (185–155 ka) with pronounced oscillations in tree population extent, and a later period (155–135 ka) with much smaller tree populations and subdued oscillations. This pattern is analogous to the MIS 3/MIS 2 division during the last glacial in the same sequence, although the early part of MIS 6 had larger Pinus populations and fewer temperate trees relative to the equivalent interval in MIS 3. This implies cooler and wetter conditions, which is somewhat counterintuitive given the high summer insolation during MIS 6e, but is in line with other palaeoclimatic evidence from the Mediterranean. Comparison with North Atlantic records suggests that despite the absence of pronounced iceberg discharges during MIS 6, North Atlantic millennial‐scale variability had a significant downstream impact on tree populations in north‐west Greece. Copyright © 2011 John Wiley & Sons, Ltd.
A reassessment of late glacial – Holocene diatom oxygen isotope record from Lake Baikal using a geochemical mass‐balance approach
Authors: Mackay Anson W. , Swann George E. A. , Brewer Tim S. , Leng Melanie J. , Morley David W. , Piotrowska Natalia , Rioual Patrick , White Dustin
Published: July 2011

We present a new palaeoenvironmental record of hydrological variability in Lake Baikal, based on re‐modelled δ18Odiatom values of diatom silica (δ18Omodelled), where the residual contaminants are identified and compensated for using electron optical imaging and whole‐sample geochemistry. δ18Omodelled interpretations are based on the balance between rivers with high δ18O values and rivers with low δ18O values. Isotopic variability is related to latitudinal differences in precipitation which feed these rivers. The δ18Omodelled record suggests that rather moist conditions prevailed in the Lake Baikal region during the latter stages of the Younger Dryas. Throughout the Holocene, episodes of low δ18Omodelled values are, in general, in good agreement with increases in percentage haematite‐stained grains in North Atlantic sediments (indicative of ice‐rafted debris events). Rivers with southerly catchments dominate fluvial input especially between c. 3.3 and 2 cal ka BP, concurrent with high precipitation in the Lake Baikal region. Copyright © 2011 John Wiley & Sons, Ltd.
Inelastic light scattering studies of diffuse phase transition in ferroelectric Sr1.9Ca0.1NaNb5O15 thin films
Authors: Liu W. C. , Zhou W. , Sooryakumar R. , Mak C. L.
Published: July 2011

The dynamic behavior of highly oriented ferroelectric Sr1.9Ca0.1NaNb5O15 thin films has been investigated by Brillouin light scattering over a wide temperature range between 25 and 450 °C. The temperature variations of the full‐width at half‐maximum (FWHM) of the central peak (CP) are found to exhibit marked changes around the Curie temperature (Tc = 246 °C). The CP reveals a relaxational mode behavior, which is attributed to thermally activated fast relaxation of polar nanoregions (PNRs). The width of the CP decreases steadily upon cooling from ∼400 °C to Tc and shows little subsequent change within the ferroelectric state, indicating an increase of the number of PNRs and a slowing down of their dynamics. By using a modified superparaelectric model, the activation energy (H0) of the relaxation processes and the Burns temperature (TB) are determined to be 2939 and 385 °C, respectively. The evidence for this diffuse phase transition provided by Brillouin scattering is in agreement with results obtained from the temperature‐dependent dielectric permittivity, refractive index, and Raman spectra. Copyright © 2011 John Wiley & Sons, Ltd.
The symptom‐to‐diagnosis delay in soft tissue sarcoma influence the overall survival and the development of distant metastasis
Authors: Nakamura Tomoki , Matsumine Akihiko , Matsubara Takao , Asanuma Kunihiro , Uchida Astumasa , Sudo Akihiro
Published: July 2011

Background

There are very few reports regarding the impact of the symptom that caused patients to consult a doctor and the symptom‐to‐diagnosis delay on survival for soft tissue sarcoma patients. The purpose of this study is to investigate whether symptom‐treatment delay are associated with the presence of metastasis at diagnosis, overall survival and distant metastasis‐free survival in primary soft tissue sarcomas.

Methods

This study retrospectively reviewed the medical records of 100 newly diagnosed patients with primary soft tissue sarcoma referred to our hospital.

Results

Eighteen of 100 sarcoma patients had distant metastases at diagnosis. A multivariate logistic regression analysis revealed that tumor size, tumor site, and the interval between the onset of the initial symptom and the first consultation to our hospital were all found to be significant predictors of distant metastases at diagnosis. The patients (n = 48) who were treated within the first 6 months from the onset of the initial symptom showed significantly better cumulative overall survival rate than those (n = 34) who were diagnosed more than 6 months (5‐years: 77.0% vs. 59.7%).

Conclusion

These results suggest that a shorter delay may have a beneficial effect on treatment options and outcome, improving survival in some sarcoma patients. J. Surg. Oncol. 2011; 104:771–775. © 2011 Wiley Periodicals, Inc.
Quantitative comparison of surgical margin histology following excision with traditional electrosurgery and a low‐thermal‐injury dissection device
Authors: Ruidiaz Manuel E. , Cortes‐Mateos Maria J. , Sandoval Sergio , Martin David T. , Wang‐Rodriguez Jessica , Hasteh Farnaz , Wallace Anne , Vose Joshua G. , Kummel Andrew C. , Blair Sarah L.
Published: July 2011

Background

This study is the first to examine in vivo the effect of thermal injury in breast conservation pathology in a direct comparison of traditional electrosurgery and an alternative low‐thermal‐injury device.

Methods

A prospective study of 20 consecutive subjects with biopsy‐proven invasive ductal carcinoma (IDC) tumors 1 cm was conducted. Following excision, incisions were made into the tumor with the two devices. Thermal injury depth, margin distance, tissue type, and histological effect were compared on the same breast tissue cut with each excision instrument. A probability evaluation of close and positive margin cases for the true tumor margins was conducted.

Results

Compared to traditional electrosurgery, the low‐thermal‐injury instrument reduced collagen denaturation depth from 435 to 102 µm (77%), fused tissue depth from 262 to 87 µm (67%), and distortion depth from 1,132 to 774 µm (30%).

Conclusions

Based on analysis of the close subset of the true margins, using the traditional electrosurgical device in place of the low‐thermal‐injury device would have resulted in 48% of the close margin samples being negatively converted to false‐positive, and in 11% converting from close to false‐negative. The methodology of this work may be readily applied to larger, more definitive studies. J. Surg. Oncol. 2011; 104:746–754. © 2011 Wiley Periodicals, Inc.
Lysophosphatidic acid (LPA) and endothelial differentiation gene (Edg) receptors in human pancreatic cancer
Authors: LV G.M. , Li P. , Wang W.D. , Wang Sh.K. , Chen J.F. , Gong Y.L.
Published: July 2011

Lysophosphatidic acid (LPA) is a naturally occurring phospholipid with diverse effects on various cells, ranging from immediate morphological change to long‐lasting cellular function alteration such as induction of stimulation of cell proliferation, survival, drug resistance, and motility. LPA interacts with cells through specific cell surface receptors. LPA1/Edg‐2, LPA2/Edg‐4, and LPA3/Edg‐7 are three most common LPA receptors. Herein we review the roles of LPA and its receptors in the carcinogenesis of human malignancies, with focus on pancreatic cancer. J. Surg. Oncol. 2011; 104:685–691. © 2011 Wiley Periodicals, Inc.
Photodynamic therapy outcome for T1/T2 N0 oral squamous cell carcinoma
Authors: Jerjes Waseem , Upile Tahwinder , Hamdoon Zaid , Alexander Mosse Charles , Morcos Mira , Hopper Colin
Published: July 2011

Introduction

This new prospective clinical study assessed the oncological outcomes following surface illumination mTHPC‐photodynamic therapy of T1/T2 N0 oral squamous cell carcinoma (OSCC) patients.

Material/Methods

Thirty‐eight patients participated in this study. Their mean age at the first diagnosis of OSCC was 58.0 years. Common clinical presentation was an ulcer mainly identified in the tongue, floor of mouth (FOM), or buccal mucosa. Current and ex‐smokers represented 89.5% of the cohort; while current and ex‐drinkers were 86.8%. Clinically nine patients had T1 disease while 29 had T2 disease.

Results

Pathological analysis revealed that 12 patients had well differentiated SCC, 16 moderately differentiated and 10 had poorly‐differentiated cancer. All patients were discussed in a multidisciplinary meeting and, subsequently, underwent mTHPC‐PDT. PDT was repeated in 6‐ to 7‐month period following the first round when residual tumor was identified in the treated site. At last clinic review post‐PDT, 26/38 patients showed complete normal clinical appearance of their oral mucosa in the primary tumor site. Recent surgical biopsies from the study cohort showed that 17 had normal mucosa, five with hyperkeratinization, 10 with dysplastic changes and six showed recurrent SCC. The overall recurrence was 15.8% and the 5‐year survival was 84.2%. Death from loco‐regional and distant disease spread was identified in three patients. The recurrence group comprised six patients. Most common presentation was an ulcer involving the buccal mucosa or retromolar area, identified in current or ex‐smokers and current drinkers. The surgical margins in this group were also evaluated following laser or surgical excision and reconstruction.

Conclusions

mTHPC‐photodynamic therapy (up to three rounds) is a comparable modality to other traditional interventions in the management of low‐risk tumors of the oral cavity. Although, sometimes, multiple rounds of the treatment is required, morbidity following PDT is far less when compared to the three conventional modalities: surgery, radiotherapy, and chemotherapy. Lasers Surg. Med. 43:463–469, 2011. © 2011 Wiley‐Liss, Inc.