bluuebunny/crossref_metadata_2025 huggingface dataset:
Glutamate decarboxylase67 is expressed in hippocampal mossy fibers of temporal lobe epilepsy patients
Authors: Sperk Günther , Wieselthaler‐Hölzl Anna , Pirker Susanne , Tasan Ramon , Strasser Sarah S. , Drexel Meinrad , Pifl Christian , Marschalek Julian , Ortler Martin , Trinka Eugen , Heitmair‐Wietzorrek Katja , Ciofi Philippe , Feucht Martha , Baumgartner Christoph , Czech Thomas
Published: April 2011

Recently, expression of glutamate decarboxylase‐67 (GAD67), a key enzyme of GABA synthesis, was detected in the otherwise glutamatergic mossy fibers of the rat hippocampus. Synthesis of the enzyme was markedly enhanced after experimentally induced status epilepticus. Here, we investigated the expression of GAD67 protein and mRNA in 44 hippocampal specimens from patients with mesial temporal lobe epilepsy (TLE) using double immunofluorescence histochemistry, immunoblotting, and in situ hybridization. Both in specimens with (n = 37) and without (n = 7) hippocampal sclerosis, GAD67 was highly coexpressed with dynorphin in terminal areas of mossy fibers, including the dentate hilus and the stratum lucidum of sector CA3. In the cases with Ammon's horn sclerosis, also the inner molecular layer of the dentate gyrus contained strong staining for GAD67 immunoreactivity, indicating labeling of mossy fiber terminals that specifically sprout into this area. Double immunofluorescence revealed the colocalization of GAD67 immunoreactivity with the mossy fiber marker dynorphin. The extent of colabeling correlated with the number of seizures experienced by the patients. Furthermore, GAD67 mRNA was found in granule cells of the dentate gyrus. Levels, both of GAD67 mRNA and of GAD67 immunoreactivity were similar in sclerotic and nonsclerotic specimens and appeared to be increased compared to post mortem controls. Provided that the strong expression of GAD67 results in synthesis of GABA in hippocampal mossy fibers this may represent a self‐protecting mechanism in TLE. In addition GAD67 expression also may result in conversion of excessive intracellular glutamate to nontoxic GABA within mossy fiber terminals. © 2011 Wiley Periodicals, Inc.
Histomorphometric analysis following augmentation of the posterior mandible using cancellous bone‐block allograft
Authors: Nissan Joseph , Marilena Vered , Gross Ora , Mardinger Ofer , Chaushu Gavriel
Published: April 2011

The present study was conducted to histologically and histomorphometrically evaluate the application of cancellous bone‐block allografts for the augmentation of the posterior atrophic mandible. Twenty‐four consecutive patients underwent augmentation with cancellous bone‐block allografts in the posterior mandible. A bony deficiency of at least 3 mm horizontally and/or vertically according to CT para‐axial reconstruction served as inclusion criteria. Following 6 months, 85 implants were placed and a cylindrical sample core was collected. All specimens were prepared for histological and histomorphometrical examination. Implant survival rate was 95.3%. Follow‐up ranged 12–66 months (mean 43 ± 19 months). The mean newly formed bone was 44 ± 28%, that of the residual cancellous bone‐block allograft 29 ± 24%, and of the marrow and connective tissue 27 ± 21%. Statistically significant histomorphometric differences regarding newly formed bone (69% vs. 31%, p = 0.05) were found between younger (<45 years) and older (>45 years) patients, respectively. Histomorphometric differences regarding residual cancellous bone‐block allograft (17% vs. 35%) and of the marrow and connective tissue (14% vs. 34%) were not statistically significant. Cancellous bone‐block allograft is biocompatible and osteoconductive, permitting new bone formation following augmentation of extremely atrophic posterior mandible with a two‐stage implant placement procedure. New bone formation was age‐dependent. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part A: , 2011.
Mechanisms inducing low bone density in duchenne muscular dystrophy in mice and humans
Authors: Rufo Anna , Del Fattore Andrea , Capulli Mattia , Carvello Francesco , De Pasquale Loredana , Ferrari Serge , Pierroz Dominique , Morandi Lucia , De Simone Michele , Rucci Nadia , Bertini Enrico , Bianchi Maria Luisa , De Benedetti Fabrizio , Teti Anna
Published: April 2011

Patients affected by Duchenne muscular dystrophy (DMD) and dystrophic MDX mice were investigated in this study for their bone phenotype and systemic regulators of bone turnover. Micro–computed tomographic (µCT) and histomorphometric analyses showed reduced bone mass and higher osteoclast and bone resorption parameters in MDX mice compared with wild-type mice, whereas osteoblast parameters and mineral apposition rate were lower. In a panel of circulating pro-osteoclastogenic cytokines evaluated in the MDX sera, interleukin 6 (IL-6) was increased compared with wild-type mice. Likewise, DMD patients showed low bone mineral density (BMD) Z-scores and high bone-resorption marker and serum IL-6. Human primary osteoblasts from healthy donors incubated with 10% sera from DMD patients showed decreased nodule mineralization. Many osteogenic genes were downregulated in these cultures, including osterix and osteocalcin, by a mechanism blunted by an IL-6-neutralizing antibody. In contrast, the mRNAs of osteoclastogenic cytokines IL6, IL11, inhibin-βA, and TGFβ2 were increased, although only IL-6 was found to be high in the circulation. Consistently, enhancement of osteoclastogenesis was noted in cultures of circulating mononuclear precursors from DMD patients or from healthy donors cultured in the presence of DMD sera or IL-6. Circulating IL-6 also played a dominant role in osteoclast formation because ex vivo wild-type calvarial bones cultured with 10% sera of MDX mice showed increase osteoclast and bone-resorption parameters that were dampen by treatment with an IL-6 antibody. These results point to IL-6 as an important mediator of bone loss in DMD and suggest that targeted anti-IL-6 therapy may have a positive impact on the bone phenotype in these patients. © 2011 American Society for Bone and Mineral Research
Internal audit: How to develop professional skepticism
Authors: McCoy Nicole , Burnett Royce D. , Friedman Mark E. , Morris Marc
Published: April 2011

In these unpredictable economic times, how do you produce highly regarded financial statements in the face of demands to minimize external audit costs? Many companies try to solve this problem by using their internal audit department more during the annual external audit. But that can be tricky—because the internal audit staff is required to remain independent.

The solution, say the authors of this article, is to actively develop and maintain your internal auditors' professional skepticism. And the authors give you a detailed roadmap that shows how to do that. © 2011 Wiley Periodicals, Inc.
Using text mining to monitor employee e‐mail
Authors: Tackett James A.
Published: April 2011

The Enron‐Arthur Andersen fiasco was the flashpoint that triggered the passage of the Sarbanes‐Oxley Act. Many would argue that the most egregious aspect of this auditing failure was Andersen's shredding their audit working papers when they learned a formal investigation was under way. So preserving documentation of possible ineptitude or corruption became one of the core ideas of Sarbanes‐Oxley—and the SEC now requires archiving of all business documentation affecting financial reporting.

One key area is employee e‐mail. But what's the best way for companies to monitor it? Try text mining, suggests the author of this article. And he explains what this tool is, and how to use it. © 2011 Wiley Periodicals, Inc.
Current enforcement actions against auditors
Authors: Weirich Thomas R. , Reinstein Alan
Published: April 2011

In the wake of accounting scandals, Congress and investors have favored subjecting auditors to increased sanctions. What lessons can we learn from the most recent enforcement actions against auditors? © 2011 Wiley Periodicals, Inc.
Auditor's guide to corporate social responsibility
Authors: Goldberg Stephen R. , Gist Ashley K. , Lindquist Stanton C.
Published: April 2011

Can being socially responsible serve as a successful corporate strategy? Yes, say the authors of this article. And auditors need to understand reporting standards and trends in this developing area.

Many organizations are taking responsibility for their impact on society and the environment‐and turning it into a competitive advantage. The authors give an overview for auditors: how corporate social responsibility (CSR) fits into corporate strategy, CSR reporting standards, and current trends. Auditors should pay special attention to developments in third‐party assurance, and the role of internal auditors in this area. © 2011 Wiley Periodicals, Inc.
Better understanding accounting fraud
Authors: Shapiro David M.
Published: April 2011

Investigators in many fields—including accounting, sociology, criminology, and the law—have researched accounting fraud. What general methodologies and theories have these investigators come up with? And what practical advice can they offer to handle the risk of accounting fraud? The author of this article has some answers. © 2011 Wiley Periodicals, Inc.
Management process principles
Authors: Brimson James A.
Published: April 2011

You have balanced your scorecard. You have employed Six Sigma black belts to rid your organization of non‐value‐added costs. Yet economic troubles and uncertainty persist. What remains to be done? Perhaps it's time to channel your inner Dorothy, click your shoes together, and say, “There is no place like processes.” © 2011 Wiley Periodicals, Inc.
Histochemical and ultrastructural studies of the mosquito Aedes aegypti fat body: Effects of aging and diet type
Authors: Martins Gustavo Ferreira , SerrãO José Eduardo , Ramalho‐OrtigãO José Marcelo , Pimenta Paulo Filemon Paolucci
Published: April 2011

Aedes aegypti is the principal vector of dengue world wide and a major vector of urban yellow fever. Despite its epidemiological importance, not much is known regarding cellular and structural changes in the fat body in this mosquito. Here, we applied light and transmission electron microscopies to investigate structural changes in the fat body of three groups of A. aegypti females: newly emerged, 18‐day‐old sugar‐fed, and 18‐day‐old blood‐fed. The fat body consists of a layer of cells attached to the abdomen integument, formed by trophocytes and oenocytes. Trophocytes are strongly positive for carbohydrates, while oenocytes are strongly positive for proteins and lipids. Ultrastructural analyses of trophocytes from newly emerged and 18‐day‐old blood‐fed indicate that these cells are rich in glycogen and free ribosomes. Many lipid droplets and protein granules, which are broken down after the blood meal, are also detected. In 18‐day‐old sugar‐fed, trophocytes display a disorganized cytoplasm filled with lipid droplets, and reduced numbers of free ribosomes, glycogen, rough endoplasmic reticulum (RER) and mitochondria. Following a blood meal, the RER and mitochondria display enlarged sizes, suggestive of increased activity. With regard to oenocytes, these cells display an electron‐dense cytoplasm and plasma membrane infoldings facing the hemolymph. As the A. aegypti female ages, trophocyte and oenocyte cell nuclei become larger but decrease in diameter after blood feeding. Our findings suggest that the trophocytes and oenocytes remodeling is likely involved in functional changes of fat body that take place during aging and following a blood meal in A. aegypti females. Microsc. Res. Tech. 2011. © 2011 Wiley Periodicals, Inc.
Lobe variation effects of experimental diabetes and insulin replacement on rat prostate
Authors: Porto Elaine Manoela , Santos Sérgio Alexandre De Alcântara Dos , Ribeiro Larissa Mayumi , Lacorte Lívia Maria , Rinaldi Jaqueline Carvalho , Justulin Luis Antonio , Felisbino Sérgio Luís
Published: April 2011

We investigated the impact of diabetes with simultaneous and late insulin replacement on rat prostate growth during puberty, paying special attention to different prostatic lobes. Diabetes was induced by administration of streptozotocin (STZ) in 40‐day‐old male Wistar rats. A subset of diabetic rats underwent simultaneous insulin replacement (3 days after STZ administration), and another subset underwent a late insulin replacement (20 days after STZ administration). The ventral, dorsolateral, and anterior prostatic lobes were weighed and processed for histological, immunohistochemical, and morphometric analyses. Both diabetic and insulin‐treated animals maintained low plasma testosterone (T) concentrations, whereas dihydrotestostenore (DHT) levels were normal. Diabetic animals had a decreased gain in absolute prostatic weight when compared to age‐matched controls and insulin replacement animals. However, prostatic lobe weight in the diabetic animals was ∼100% higher, even at the beginning of the experiment. Among the lobes, the anterior lobe showed the highest weight gain in diabetic and insulin replacement conditions. Epithelial cell proliferation in all lobes was significantly reduced in diabetic animals and significantly increased in insulin replacement animals, although apoptosis was unaltered. In conclusion, diabetes diminishes, but does not abolish, prostate growth during puberty. Even late insulin administration reduces the adverse effects of this disease on the prostate. In a scenario with both low insulin and T levels, DHT and other factors may play an important role in pubertal prostate growth. The adverse effects of diabetes on the rat prostate show a variation in lobe response, suggesting that diabetes may affect human prostate zones differently. Microsc. Res. Tech. 2011. © 2011 Wiley Periodicals, Inc.
Reactions of N‐arylmaleimides with 3‐amino‐1,2,4‐triazole and 2‐aminobenzimidazole
Authors: Rudenko Roman V. , Komykhov Sergey A. , Musatov Vladimir I. , Konovalova Irina S. , Shishkin Oleg V. , Desenko Sergey M.
Published: April 2011

The reaction of 3‐amino‐1,2,4‐triazole (1) with N‐arylmaleimides leads to azolopyrimidines 4 and 5. The 2‐aminobenzimidazole (2) in the reaction with 3 gives the pyrimidobenzimidazoles 6. In similar conditions, the reaction of amine 2 with maleic anhydride (7) leads to formation of 2‐oxo‐1,2,3,4‐tetrahydropyrimido[1,2‐a]benzimidazole‐4‐carboxylic acid (8). The structures of 4, 5, 6, and 8 were proved by X‐Ray and NOE NMR measurements. J. Heterocyclic Chem., (2011)
Synthesis and insecticidal activities of novel neonicotinoid analogs bearing an amide moiety
Authors: Wu Jian , Yang Song , Song Bao‐An , Bhadury Pinaki S. , Hu De‐Yu , Zeng Song , Xie Hua‐Peng
Published: April 2011

A series of novel neonicotinoid analogs containing an amide moiety were synthesized, characterized, and subsequently evaluated for their insecticidal activity. According to the preliminary bioassay, the compounds 6c, 6e, 6f, 6j, 6n, and 6r exhibited > 50% activity against Nilaparvata lugens at 100 mg/L. Amongst the active compounds, 6f and 6r revealed insecticidal activities similar to that displayed by standard buprofezin. J. Heterocyclic Chem., (2011)
Using Morita–Baylis–Hillman acetates of 2‐azidobenzaldehydes for the synthesis of 2‐alkoxy‐3‐cyanomethylquinolines and alkyl quinoline‐3‐carboxylates
Authors: Kim Hea Jung , Jeong Eun Mi , Lee Kee‐Jung
Published: April 2011

A simple method for the synthesis of several 2‐alkoxy‐3‐cyanomethylquinolines and alkyl quinoline‐3‐carboxylates using iminophosphorane‐mediated cyclization reactions of 3‐(2‐azidophenyl)‐2‐cyanomethylpropenoates and 3‐(2‐azidophenyl)‐2‐nitromethylpropenoates has been developed. These compounds were readily obtained from the Morita–Baylis–Hillman acetates of 2‐azidobenzaldehydes using potassium cyanide or sodium nitrite, respectively. J. Heterocyclic Chem., (2011)
Clay‐supported 2‐phenyl‐1H‐imidazole derivatives for heterogeneous catalysis of Henry reaction
Authors: Holešová Sylva , Pařík Patrik , Ludwig Miroslav
Published: April 2011

Six derivatives (1, 2, 3, 4, 5, 6) of 2‐phenyl‐1H‐imidazole were tested as catalysts of Henry reaction. Three new (4, 5, 6) 2‐phenyl‐1H‐imidazole derivatives, differently substituted (thio)ureas, were synthesized and determined by 1H NMR and IR spectroscopy and elemental analysis. Two types of catalysis, homogeneous and heterogeneous, were examined and compared. Clay minerals Ca‐MMT and Cu‐MMT were used as solid supports for heterogeneous catalysis. The best results were obtained using compound 2 under conditions of heterogeneous method D from the point of view of yield and reaction time. J. Heterocyclic Chem., (2011)
In vivo detection of GABA and glutamate with MEGA‐PRESS: Reproducibility and gender effects
Authors: O'Gorman Ruth L. , Michels Lars , Edden Richard A. , Murdoch James B. , Martin Ernst
Published: April 2011

Purpose:

To evaluate the reproducibility of γ‐amino‐butyric acid (GABA) and glutamate concentrations derived using three different spectral fitting methods, and to investigate gender‐related differences in neurotransmitter levels.

Materials and Methods:

Single voxel MEGA‐edited PRESS MR spectra were acquired from a 30‐mL voxel in the dorso‐lateral prefrontal cortex in 14 adult volunteers (7 female) at 3 Tesla (3T). For each participant, four consecutive resting spectra were acquired within the same scanning session. Metabolite concentrations were derived using LCModel, jMRUI, and locally written peak fitting software. The within‐session reproducibility for each analysis method was calculated as the average coefficient of variation (CV) of the GABA and Glx (glutamate+glutamine) concentrations. Gender differences in GABA and Glx were evaluated using a two‐tailed unpaired t‐test.

Results:

LCModel provided the best reproducibility for both GABA (CV 7%) and Glx (CV 6%). GABA, Glx, and glutamate concentrations were significantly higher in the male participants, (P = 0.02, P = 0.001, and P < 0.001, respectively).

Conclusion:

GABA and glutamate can be quantified in vivo with high reproducibility (CV 6–7%) using frequency‐domain spectral fitting methods like LCModel. However, the GABA and glutamate concentrations vary significantly between men and women, emphasizing the importance of gender‐matching for studies investigating differences in neurotransmitter concentrations between mixed‐cohort groups. J. Magn. Reson. Imaging 2011;33:1262–1267. © 2011 Wiley‐Liss, Inc.
Quantifying synovitis in rheumatoid arthritis using computer‐assisted manual segmentation with 3 tesla MRI scanning
Authors: Chand Arista S. , McHaffie Alexandra , Clarke Andrew W. , Reeves Quentin , Tan Yu Mwee , Dalbeth Nicola , Williams Megan , McQueen Fiona
Published: April 2011

Purpose:

To investigate the reliability, validity and feasibility of a computer‐assisted manual segmentation method for determining the synovial membrane volume as a surrogate measure for synovitis in patients with rheumatoid arthritis (RA).

Materials and Methods:

The 3 Tesla (T) MRI scans were acquired in 22 early RA and 16 established RA patients. Synovial membrane volumes in postcontrast T1w axial images at three wrist joint regions were determined by two nonradiologist observers using a computer‐assisted manual segmentation method.

Results:

Intraobserver reliability, measured by intraclass correlation coefficients (ICCs), was excellent in the early (ICC = 0.99) and established (ICC = 0.99) RA cohorts. Interobserver reliability (mean ICC [95% Confidence Interval]) was moderate to excellent in the early and established RA groups (ICCs = 0.87 [0.68,0.94] and 0.88 [0.66, 0.96], respectively). There was a strong correlation between the synovial membrane volumes derived by segmentation and the RA MRI scoring system (RAMRIS) scores for synovitis at all joints in the early (Spearman rho = 0.86–0.96) and established (Spearman rho = 0.85–0.93) RA cohorts. The entire segmentation technique took 19 to 21 min per patient.

Conclusion:

Measurement of MRI synovitis using a computer‐assisted manual segmentation method demonstrated excellent intraobserver and very good interobserver reliability, content validity (represented by its strong correlation with RAMRIS synovitis), and moderate feasibility. J. Magn. Reson. Imaging 2011;33:1106–1113. © 2011 Wiley‐Liss, Inc.
Sensitivity of USPIO‐enhanced R2 imaging to dynamic blood volume changes in the rat kidney
Authors: Storey Pippa , Ji Lin , Li Lu‐Ping , Prasad Pottumarthi V.
Published: April 2011

Purpose:

To determine whether MRI in combination with an intravascular contrast agent is sensitive to pharmacologically induced vasodilation and vasoconstriction in the rat kidney.

Materials and Methods:

R2 imaging was performed in 25 Sprague Dawley rats at 3 Tesla in the presence of ferumoxytol, an ultrasmall superparamagnetic iron oxide (USPIO) agent with a long plasma half‐life. R2 changes were measured following manipulation of blood volume by intravenous administration of adenosine, a short‐acting vasodilator, or NG‐nitro‐L‐arginine methyl ester (L‐NAME), a long‐acting nitric oxide synthase inhibitor with known vasoconstrictive effects. As a control, R2 responses to adenosine and L‐NAME were also examined in the absence of ferumoxytol.

Results:

In the presence of ferumoxytol, adenosine induced a significant increase in R2, while L‐NAME produced a reduction, although the latter was not statistically significant. Control experiments revealed small R2 changes in the absence of ferumoxytol. An incidental finding was that the cross‐sectional area of the kidney also varied dynamically with adenosine and L‐NAME.

Conclusion:

Our results suggest that ferumoxytol‐enhanced R2 imaging is sensitive to adenosine‐induced vasodilation. The responses to L‐NAME, however, were not statistically significant. The variations in kidney size and the R2 changes in the absence of ferumoxytol may reflect alterations in the volume of the renal tubules. J. Magn. Reson. Imaging 2011;33:1091–1099. © 2011 Wiley‐Liss, Inc.
Assessment of small bowel motility function With cine‐MRI using balanced steady‐state free precession sequence
Authors: Wakamiya Makoto , Furukawa Akira , Kanasaki Shuzo , Murata Kiyoshi
Published: April 2011

Purpose:

To evaluate the use of cine‐magnetic resonance imaging (MRI) with a steady‐state free precession sequence to monitor and assess small bowel motility.

Materials and Methods:

Sequential MRI, using a balanced steady‐state free precession sequence, was performed in eight healthy male volunteers at 0, 15, 30, 45, and 60 minutes after oral administration of 1500 mL of nonabsorbable fluid to monitor small bowel contractions. Using the cine‐mode display, small bowel contractions were reviewed and the luminal diameter was measured on each image to obtain frequency and amplitude of bowel contractions.

Results:

The oral preparation was well tolerated without major complications. Cine‐MRI provided high temporal, spatial, and contrast resolution for monitoring bowel contractions. Mean values with standard deviations of frequency and amplitude of bowel contractions were 6.0 ± 2.98/min and 10.4 ± 4.53 mm, respectively, and were 5.1 ± 3.38/min and 9.59 ± 5.57 mm at the jejunal loops and 6.9 ± 2.22/min and 11.2 ± 3.06 mm at the ileal loops. With the passage of luminal fluid, frequency of bowel contractions decreased and the bowels tended to pause their contractions.

Conclusion:

Cine‐MRI provides sufficient dynamic images to observe small bowel contractions. Measurement of bowel caliber permits calculation of amplitude and frequency of the contractions for characterization and quantitative assessment of small bowel motility function. J. Magn. Reson. Imaging 2011;33:1235–1240. © 2011 Wiley‐Liss, Inc.
Quality assessment of high angular resolution diffusion imaging data using bootstrap on Q‐ball reconstruction
Authors: Cohen‐Adad Julien , Descoteaux Maxime , Wald Lawrence L.
Published: April 2011

Purpose:

To develop a bootstrap method to assess the quality of High Angular Resolution Diffusion Imaging (HARDI) data using Q‐Ball imaging (QBI) reconstruction.

Materials and Methods:

HARDI data were re‐shuffled using regular bootstrap with jackknife sampling. For each bootstrap dataset, the diffusion orientation distribution function (ODF) was estimated voxel‐wise using QBI reconstruction based on spherical harmonics functions. The reproducibility of the ODF was assessed using the Jensen‐Shannon divergence (JSD) and the angular confidence interval was derived for the first and the second ODF maxima. The sensitivity of the bootstrap method was evaluated on a human subject by adding synthetic noise to the data, by acquiring a map of image signal‐to‐noise ratio (SNR) and by varying the echo time and the b‐value.

Results:

The JSD was directly linked to the image SNR. The impact of echo times and b‐values was reflected by both the JSD and the angular confidence interval, proving the usefulness of the bootstrap method to evaluate specific features of HARDI data.

Conclusion:

The bootstrap method can effectively assess the quality of HARDI data and can be used to evaluate new hardware and pulse sequences, perform multifiber probabilistic tractography, and provide reliability metrics to support clinical studies. J. Magn. Reson. Imaging 2011;33:1194–1208. © 2011 Wiley‐Liss, Inc.
Measurement of temperature dependent changes in bone marrow using a rapid chemical shift imaging technique
Authors: Taylor Brian A. , Elliott Andrew M. , Hwang Ken‐Pin , Shetty Anil , Hazle John D. , Stafford R. Jason
Published: April 2011

Purpose:

To provide quantitative temperature monitoring for thermal therapies in bone marrow by measuring temperature‐dependent signal changes in the bone marrow of ex vivo canine femurs heated with a 980‐nm laser at 1.5T and 3.0T.

Materials and Methods:

Using a multi‐gradient echo (≤16) acquisition and signal modeling with the Stieglitz–McBride algorithm, the temperature sensitivity coefficients (TSC, ppm/°C) of water and multiple lipid components' proton resonance frequency (PRF) values are measured at high spatiotemporal resolutions (1.6 × 1.6 × 4 mm3, ≤5 seconds). Responses in R2* and amplitudes of each peak were also measured as a function of temperature simultaneously.

Results:

Calibrations demonstrate that lipid signal may be used to compensate for B0 errors to provide accurate temperature readings (<1.0°C). Over a temperature range of 17.2–57.2°C, the TSCs after correction to a bulk methylene reference are −0.87 × 10−2 ± 4.7 × 10−4 ppm/°C and −0.87 × 10−2 ± 4.0 × 10−4 ppm/°C for 1.5T and 3.0T, respectively.

Conclusion:

Overall, we demonstrate that accurate and precise temperature measurements can be made in bone marrow. In addition, the relationship of R2* and signal amplitudes with respect to temperature are shown to differ significantly where conformal changes are predicted by Arrhenius rate model analysis. J. Magn. Reson. Imaging 2011;33:1128–1135. © 2011 Wiley‐Liss, Inc.
Diffusion‐weighted MR imaging in pancreatic endocrine tumors correlated with histopathologic characteristics
Authors: Wang Yi , Chen Zongming E. , Yaghmai Vahid , Nikolaidis Paul , McCarthy Robert J. , Merrick Laura , Miller Frank H.
Published: April 2011

Purpose:

To retrospectively assess apparent diffusion coefficients (ADCs) of different subtypes of pancreatic endocrine tumors based on the World Health Organization (WHO) classification system and analyze the potentially responsible histopathologic characteristics.

Materials and Methods:

Following Institutional Review Board (IRB) approval, 18 patients with surgical pathology‐proven pancreatic endocrine tumors were evaluated. Tumors were subcategorized based on the WHO grading classification into well‐differentiated tumors with benign and uncertain behavior and endocrine carcinomas with well and poor differentiation. ADCs were measured on diffusion‐weighted (DW) images and compared using Student's t‐test and one‐way analysis of variance. The correlation between ADCs, tumor cellularity, Ki‐67 labeling index (an index of cell growth), and extracellular fibrosis were analyzed.

Results:

A difference was demonstrated in mean ADCs between well‐differentiated endocrine tumors (1.75 ± 0.53) and endocrine carcinomas (1.00 ± 0.19 × 10−3mm2/sec) (P < 0.01). After excluding the three well‐differentiated endocrine tumors with benign behavior and marked fibrosis, a significant inverse correlation between ADC values and cellularity of endocrine tumors was observed. An inverse correlation was seen between Ki‐67 labeling index and ADC values (r = −0.70; P < 0.01).

Conclusion:

Tumor cellularity and/or extracellular fibrosis may account for various ADCs in pancreatic endocrine tumors. ADC correlates well with the Ki‐67 labeling index and may help predict growth of endocrine tumors. J. Magn. Reson. Imaging 2011;33:1071–1079. © 2011 Wiley‐Liss, Inc.
Whole‐body MRI including diffusion‐weighted imaging (DWI) for patients with recurring prostate cancer: Technical feasibility and assessment of lesion conspicuity in DWI
Authors: Eiber Matthias , Holzapfel Konstantin , Ganter Carl , Epple Kathrin , Metz Stephan , Geinitz Hans , Kübler Hubert , Gaa Jochen , Rummeny Ernst J. , Beer Ambros J.
Published: April 2011

Purpose:

To evaluate the principal methodological aspects of whole‐body magnetic resonance imaging (MRI) including diffusion‐weighted imaging (DWI) with background suppression using a time‐optimized protocol for restaging of prostate cancer patients in a technical feasibility study.

Materials and Methods:

Seventeen patients underwent MRI at 1.5T from the base of the skull to the proximal thigh using axial T1‐weighted (T1w), T2w short‐tau inversion recovery (STIR), and DWI (b‐values: 50 and 500 s/mm2) and sagittal T1w and T2w STIR of the spine. Apparent diffusion coefficient (ADC) values of liver, spleen, kidney, muscle, and bone were measured. Image quality in DWI was assessed by using a scale from 0–9. Contrast‐to‐noise ratios (CNRs) of lymph node and bone metastases were determined in T1w, T2w STIR, and DWI. Bone metastases were further subclassified according to their Hounsfield units (HU) in computed tomography (CT).

Results:

Mean acquisition and mean room times were 66:20 and 75:21 minutes, respectively. ADC values of normal organs showed good concordance with reported data. Good to excellent image quality was observed for DWI (mean scores 7.41–8.00) with the exception of the neck (mean score 4.76). CNR of DWI (b‐value 50 s/mm2) for lymph node metastases was clearly superior compared to all other sequences. For bone metastases T1w performed significantly better for sclerotic lesions (HU > 600), DWI (b‐value 50 s/mm2) for nonsclerotic lesion (HU < 300).

Conclusion:

In patients with recurrent prostate cancer a whole‐body MR protocol including DWI is technically robust. Due to the high CNR of DWI compared to T1w and T2w STIR, detection of malignant lesions should be facilitated by DWI, except for sclerotic bone metastases. J. Magn. Reson. Imaging 2011;33:1160–1170. © 2011 Wiley‐Liss, Inc.
Quantification of background enhancement in breast magnetic resonance imaging
Authors: Klifa C. , Suzuki S. , Aliu S. , Singer L. , Wilmes L. , Newitt D. , Joe B. , Hylton N.
Published: April 2011

Purpose:

To present a novel technique for measuring tissue enhancement in breast fibroglandular tissue regions on contrast‐enhanced breast magnetic resonance imaging (MRI) aimed at quantifying the enhancement of breast parenchyma, also known as “background enhancement.”

Materials and Methods:

Our quantitative method for measuring breast MRI background enhancement was evaluated in a population of 16 healthy volunteers. We also demonstrate the use of our new technique in the case study of one subject classified as high risk for developing breast cancer who underwent 3 months of tamoxifen therapy.

Results:

We obtained quantitative measures of background enhancement in all cases. The high‐risk patient exhibited a 37% mean reduction in background enhancement with treatment.

Conclusion:

Our quantitative method is a robust and promising tool that may allow investigators to quantify and document the potential adverse effect of background enhancement on diagnostic accuracy in larger populations. J. Magn. Reson. Imaging 2011;33:1229–1234. © 2011 Wiley‐Liss, Inc.
MRI for staging lymphoma: Whole‐body or less?
Authors: Kwee Thomas C. , Akkerman Erik M. , Fijnheer Rob , José Kersten Marie , Zsíros József , Ludwig Inge , Bierings Marc B. , Vermoolen Malou A. , van Leeuwen Maarten S. , Stoker Jaap , Nievelstein Rutger A.J.
Published: April 2011

Purpose:

To assess whether whole‐body MRI detects more clinically relevant lesions (i.e., leading to a change in Ann Arbor stage) than an MRI protocol that only includes the head/neck and trunk (i.e., from cranial vertex to groin, excluding the arms) in patients with lymphoma.

Materials and Methods:

One hundred consecutive patients with newly diagnosed lymphoma prospectively underwent T1‐weighted and T2‐weighted short inversion time inversion recovery whole‐body MRI. The number of lymphomatous sites at MRI with a field of view (FOV) limited to the head/neck and trunk, and the additional number of lymphomatous sites at whole‐body MRI and their influence on Ann Arbor stage were determined.

Results:

At MRI with a FOV limited to the head/neck and trunk, 507 sites were classified as lymphomatous. At whole‐body MRI, 7 additional sites outside the head/neck and trunk in 7 patients (7.0%; 95% confidence interval: 3.4–13.8%) were classified as lymphomatous, but Ann Arbor stage never changed.

Conclusion:

Whole‐body MRI did not detect any clinically relevant lesions outside the FOV of an MRI protocol that only includes the head/neck and trunk. Therefore, it may be sufficient to only include the head/neck and trunk when using MRI for staging lymphoma. J. Magn. Reson. Imaging 2011;33:1144–1150. © 2011 Wiley‐Liss, Inc.
Correlation of diffusion‐weighted imaging data with apoptotic and proliferation indexes in CT26 colorectal tumor homografts in balb/c mouse
Authors: Zhang Xiao‐Yan , Sun Ying‐Shi , Tang Lei , Xue Wei‐Cheng , Zhang Xiao‐Peng
Published: April 2011

Purpose:

To investigate whether the percentage of apparent diffusion coefficient (ADC) changes could be used as an imaging marker related to tumor cell apoptotic and Ki‐67 proliferation index of tumors.

Materials and Methods:

Mice bearing CT26 colorectal carcinoma tumors were scanned before radiotherapy, then divided into radiotherapy (n = 24) and control groups (n = 24). Diffusion‐weighted imaging (DWI) and anatomic T2WI were performed on six randomly chosen mice in total from two groups at different timepoints after radiotherapy (4, 8, 12 hours, 1, 2, 3, 5, 7 days). After imaging, six animals were sacrificed at each timepoint and histological analyses were undertaken. ADC maps were calculated on a pixel‐by‐pixel basis using built‐in software (Functool, GE). Regions of interest were manually circumscribed for all high‐signal areas on lesions observed during DWI. The percentage of ADC changes were calculated at predefined timepoints and compared with the apoptotic and proliferation index from the histological analyses by using the Pearson correlation test.

Results:

A significant positive correlation was found between the percentage of ADC changes of the viable tissue and apoptotic index. A significant negative correlation was found between the percentage of ADC changes of the viable tissue and Ki‐67 proliferation index.

Conclusion:

Our results suggest that the percentage of ADC changes can be used as a measurement of cell apoptotic and proliferation index in colorectal carcinoma. J. Magn. Reson. Imaging 2011;33:1171–1176. © 2011 Wiley‐Liss, Inc.
Optimizing the osteogenic potential of adult stem cells for skeletal regeneration
Authors: Lim Jung Yul , Loiselle Alayna E. , Lee Jeong Soon , Zhang Yue , Salvi Joshua D. , Donahue Henry J.
Published: April 2011

Adult stem cells, including mesenchymal stem cells, display plasticity in that they can differentiate toward various lineages including bone cells, cartilage cells, fat cells, and other types of connective tissue cells. However, it is not clear what factors direct adult stem cell lineage commitment and terminal differentiation. Emerging evidence suggests that extracellular physical cues have the potential to control stem cell lineage specification. In this perspective article, we review recent findings on biomaterial surface and mechanical signal regulation of stem cell differentiation. Specifically, we focus on stem cell response to substrate nanoscale topography and fluid flow induced shear stress and how these physical factors may regulate stem cell osteoblastic differentiation in vitro. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 29:1627–1633, 2011
Separation and determination of 11 marker pteridines in human urine by liquid chromatography and fluorimetric detection
Authors: de Llanos Alicia M. , Espinosa‐Mansilla Anunciación , Cañada‐Cañada Florentina , de la Peña Arsenio M.
Published: April 2011

A simple liquid chromatographic method has been developed to achieve the complete separation and determination of a wide range of pteridinic compounds and creatinine (CREA) in urine samples, in just one run. The influences of mobile phase composition and buffer pH have been studied. The optimized mobile phase was composed of a Tris‐HCl buffer (15 mmol/L) at pH 6.10 solution (eluent A) and a Tris‐HCl buffer (15 mmol/L) at pH 6.40 solution (eluent B), in gradient mode. Analytes were determined by fluorimetric detection, exciting at 272 nm, and measuring the fluorescence emission at three wavelengths, 410, 445 and 465 nm. CREA, as a reference of metabolites excretion in urine, was determined by photometric detection at 230 nm. Pteridines detection limits varied from 0.2 to 6.1 ng/mL, and 0.2 g/mL for CREA. Calculated precision values expressed as RSD (%) varied from 1.1 to 5.9. Two different oxidation procedures for urine samples were optimized. The neopterin/biopterin ratios found were 0.98 and 0.86 for adults and children, respectively, by means of the alkaline iodide/iodine oxidation and 0.45 and 0.57 using neutral KMnO4 oxidation.
Chest computed tomography is more likely to show latent tuberculosis foci than simple chest radiography in liver transplant candidates
Authors: Lyu Jiwon , Lee Sung-Gyu , Hwang Shin , Lee Sang-Oh , Cho Oh-Hyun , Chae Eun Jin , Lee Sang Do , Kim Woo Sung , Kim Dong Soon , Shim Tae Sun
Published: April 2011

Although the detection and treatment of latent tuberculosis infections (LTBIs) in transplant candidates are essential, current diagnostic methods for LTBIs are limited, especially in immunocompromised subjects. Pretransplant chest computed tomography (CT) may reveal more LTBI foci and thus predict the development of posttransplant tuberculosis (TB) more efficiently; however, this hypothesis has not yet been investigated. Thirty-six liver transplantation (LT) recipients who developed TB (the TB group) and 144 LT recipients who did not develop TB (the control group) were retrospectively enrolled into a study with a nested case-control design, and their clinical characteristics and radiological findings were compared. Tuberculin skin tests (TSTs) were not performed, and none of these patients had been treated for LTBIs. Thirty-six of 2549 LT recipients (1.4%) were diagnosed with TB after LT (median = 10 months, range = 1–80 months). Twenty-eight patients (77.8%) successfully completed the treatment. There were no significant differences in the clinical characteristics of the 2 groups. Abnormal CT findings (40.0% versus 17.3%, P = 0.018) and chest X-ray (CXR) findings (25.0% versus 11.8%, P = 0.044) suggestive of healed TB were significantly more frequent in the TB group versus the control group. Of the 10 patients who underwent chest CT and developed TB, 5 (50%) showed abnormal findings only on chest CT scans, whereas their CXR results were normal. In conclusion, a pretransplant chest CT scan is more likely to show an LTBI than a CXR in those with post-LT TB. The usefulness of chest CT along with traditional methods such as TSTs for LTBI screening should be further investigated. Liver Transpl 17:963–968, 2011. © 2011 AASLD.
Is the Reduction in Tracer Diffusivity under Nanoscopic Confinement Related to a Frustrated Segmental Mobility?
Authors: Napolitano Simone , Rotella Cinzia , Wübbenhorst Michael
Published: April 2011

We developed an experimental method for the determination of the tracer diffusivity Dtr in ultrathin polymer films, and the changes in the segmental mobility of tracer molecules while they diffuse through matrices of different thickness and get adsorbed onto a target substrate. Dtr starts decreasing already at 120–150 nm and drops to 1% of its bulk value in films as thin as 7.5 nm. We discuss the results highlighting a strong decoupling between the reduction in mass transport at the nanoscale and the increase in the glass transition temperature determined via capacitive dilatometry together with a breakdown of the Stokes–Einstein relation between orientational and translational degrees of freedom.

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Precision Synthesis of Poly(3‐hexylthiophene) from Catalyst‐Transfer Suzuki−Miyaura Coupling Polymerization
Authors: Yokozawa Tsutomu , Suzuki Ryosuke , Nojima Masataka , Ohta Yoshihiro , Yokoyama Akihiro
Published: April 2011

tBu3 PPd(Ph)Br (1)‐catalyzed Suzuki‐Miyaura coupling polymerization of 2‐(4‐hexyl‐5‐iodo‐2‐thienyl)‐4,4,5,5‐tetramethyl‐1,3,2‐dioxaborolane (2) was investigated. Monomer 2 was polymerized with 1 at 0 °C in the presence of CsF and 18‐crown‐6 in THF containing a small amount of water to yield P3HT with a narrow molecular weight distribution and almost perfect head‐to‐tail regioregularity. The $\overline {M} _{{\rm n}} $ values increased up to 11 400 g · mol−1 in proportion to the feed ratio of 2 to 1. The MALDI‐TOF mass spectra showed that P3HT with moderate molecular weight uniformly had a phenyl group at one end and a hydrogen atom at the other, indicating involvement of a catalyst‐transfer mechanism. Successive 1‐catalyzed polymerization of fluorene monomer 3 and then 2 yielded a well‐defined block copolymer of polyfluorene and P3HT.

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Combining RAFT Radical Polymerization and Click/Highly Efficient Coupling Chemistries: A Powerful Strategy for the Preparation of Novel Materials
Authors: Harvison M. Alyse , Lowe Andrew B.
Published: April 2011

This paper highlights the powerful combination of reversible addition–fragmentation chain transfer (RAFT) radical polymerization and various click/coupling chemistries. This is not an exhaustive review but rather an overview demonstrating the impressive possibilities that the “marriage” of these two synthetic approaches offers in modern macromolecular design and synthesis.

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Pupillary unrest correlates with arousal symptoms and motor signs in Parkinson disease
Authors: Jain Samay , Siegle Greg J. , Gu Chen , Moore Charity G. , Ivanco Larry S. , Studenski Stephanie , Greenamyre J. Timothy , Steinhauer Stuart R.
Published: April 2011

Background:

Arousal symptoms (e.g., sleepiness) are common in Parkinson's disease, and pupillary unrest (spontaneous changes in pupil diameter) is positively associated with sleepiness. We explored pupillary unrest in Parkinson's disease.

Methods:

Arousal symptoms (Epworth sleepiness scale and sleep/fatigue domain of the nonmotor symptoms scale for Parkinson's disease) and pupillary unrest were assessed in 31 participants (14 patients with Parkinson's disease, 17 controls). Effect sizes and t tests compared patients with Parkinson's disease with control participants. Correlation coefficients were calculated among arousal symptoms, pupillary unrest, and Unified Parkinson Disease Rating Scale Part III. Linear regression was performed with arousal symptoms or pupillary unrest as outcome.

Results:

Participants with Parkinson's disease reported more arousal symptoms than controls. Pupillary unrest, arousal symptoms, and Unified Parkinson Disease Rating Scale Part III were positively correlated. The association between nonmotor symptoms scale–sleep score and pupillary unrest was higher in participants with Parkinson's disease than controls and higher in those with more Parkinsonian motor signs. Unified Parkinson Disease Rating Scale Part III was positively associated with pupillary unrest.

Conclusions:

Pupillary unrest correlates with motor and nonmotor features associated with Lewy‐related pathology, suggesting it may be a nonmotor marker of progression in Parkinson's disease. © 2011 Movement Disorder Society
Increased cortical hyperexcitability and exaggerated myoclonus with aging in benign adult familial myoclonus epilepsy
Authors: Hitomi Takefumi , Ikeda Akio , Kondo Takayuki , Imamura Hisaji , Inouchi Morito , Matsumoto Riki , Terada Kiyohito , Kanda Masutaro , Matsuhashi Masao , Nagamine Takashi , Shibasaki Hiroshi , Takahashi Ryosuke
Published: April 2011

The clinical implications of enlarged early cortical components of somatosensory evoked potentials in benign adult familial myoclonus epilepsy remain unknown. Somatosensory evoked potentials following electrical stimulation of the median nerve at the wrist were studied in 16 patients with a clinical diagnosis of benign adult familial myoclonus epilepsy (7 men and 9 women; mean age, 51 ± 18 years) and 19 age‐matched apparently healthy control subjects (11 men and 8 women; mean age, 49 ± 18 years). Giant somatosensory evoked potentials were observed in 13 of the 16 patients. P25 and N35 amplitudes in the patient group were 11.4 ± 6.1 and 19.2 ± 11.5 μV, respectively, and both were significantly larger compared with those in control subjects (P = 0.008 for P25 and P < 0.0001 for N35). There was a significant positive relationship between age at somatosensory evoked potential examination and N20, P25, and N35 amplitudes, both in the patient and in the control groups (P < 0.05). The linear regression gradient of the N35 amplitude with respect to age was significantly larger in the patient group than in the control group (P = 0.04). Furthermore, regression analysis showed a significant positive relationship between the myoclonus rating scale and age at time of somatosensory evoked potential examination (R = 0.645, P = 0.007). Somatosensory evoked potential amplitude increased with age in patients with benign adult familial myoclonus epilepsy to a greater extent than in the control subjects, which suggests a progressive increase in cortical excitability based on progressive pathophysiology in benign adult familial myoclonus epilepsy. © 2011 Movement Disorder Society
Abnormal functional connectivity in focal hand dystonia: Mutual information analysis in EEG
Authors: Jin Seung‐Hyun , Lin Peter , Auh Sungyoung , Hallett Mark
Published: April 2011

The aim of the present study was to investigate functional connectivity in focal hand dystonia patients to understand the pathophysiology underlying their abnormality in movement. We recorded EEGs from 58 electrodes in 15 focal hand dystonia patients and 15 healthy volunteers during rest and a simple finger‐tapping task that did not induce any dystonic symptoms. We investigated mutual information, which provides a quantitative measure of linear and nonlinear coupling, in the alpha, beta, and gamma bands. Mean mutual information of all 58 channels and mean of the channels of interest representative of regional functional connectivity over sensorimotor areas (C3, CP3, C4, CP4, FCz, and Cz) were evaluated. For both groups, we found enhanced mutual information during the task compared with the rest condition, specifically in the beta and gamma bands for mean mutual information of all channels, and in all bands for mean mutual information of channels of interest. Comparing the focal hand dystonia patients with the healthy volunteers for both rest and task, there was reduced mutual information in the beta band for both mean mutual information of all channels and mean mutual information of channels of interest. Regarding the properties of the connectivity in the beta band, we found that the majority of the mutual information differences were from linear connectivity. The abnormal beta‐band functional connectivity in focal hand dystonia patients suggests deficient brain connectivity. © 2011 Movement Disorder Society