bluuebunny/crossref_metadata_2025 huggingface dataset:
Relationships among parenting practices, parental stress, child behaviour, and children's social‐cognitive development
Authors: Guajardo Nicole R. , Snyder Gregory , Petersen Rachel
Published: July 2008

The present study included observational and self‐report measures to examine associations among parental stress, parental behaviour, child behaviour, and children's theory of mind and emotion understanding. Eighty‐three parents and their 3‐ to 5‐year‐old children participated. Parents completed measures of parental stress, parenting (laxness, overreactivity), and child behaviour (internalizing, externalizing); children completed language, theory of mind, and emotion understanding measures. Parent–child interactions also were observed (N=47). Laxness and parenting stress predicted children's theory of mind performance and parental usage of imitative gestures and vocalizations accounted for unique variance in emotion understanding. Associations also were found between child behaviour and emotion understanding. Results provide support for direct and indirect associations between parent–child interactions and early social‐cognitive development. Copyright © 2008 John Wiley & Sons, Ltd.
International insolvency law in the Netherlands: The pre‐draft of title 10
Authors: Wessels Bob
Published: July 2008

In November 2007, in the Netherlands, the Insolvency Law Committee published a pre‐draft for a new Insolvency Act, to replace its present Bankruptcy Act of 1896. One of the most interesting renewals the Committee has presented is Title 10, which contains provisions concerning “International Insolvency Law”, containing 35 articles, divided over five chapters. In this Article the English translation of the draft for Title 10 is presented, preceded by an introduction of these provisions. The Dutch Minister of Justice has introduce a consultation period which is open until September 15, 2008. Any comments to improve the present pre‐draft are welcome: info@bobwessels.nl. Copyright © 2008 John Wiley & Sons, Ltd.
Natural programmed cell death in T. cruzi epimastigotes maintained in axenic cultures
Authors: Jimenez V. , Paredes R. , Sosa M.A. , Galanti N.
Published: July 2008

Trypanosoma cruzi, a parasitic protozoan, is the agent of Chagas' disease or American trypanosomiasis, an endemic pathology in Latin America, affecting up to 18 million people, with high public health costs. Programmed cell death (PCD) has many functions in development and tissue remodeling in metazoans. In protozoa, it could represent concomitant or alternative mechanisms for clonal selection, immune response evasion, and population size regulation. In this work, we describe the natural occurrence of PCD in T. cruzi epimastigotes during the stationary phase of growth in axenic culture or under nutrient deprivation. Thus, we have observed phosphatidylserine externalization, cellular volume decrease, caspase‐like protein activity, and DNA fragmentation. Additionally, serum deprivation also induces autophagic characteristics such as monodansylcadaverine‐labeled vesicles accumulation and redistribution of proteins homologous to Atg8. In agreement with our results, apoptosis may play an important role in parasite survival. Then, identification and modulation of molecular targets inducing programmed cell death in T. cruzi may lead to new potential therapeutic approaches for Chagas' disease. J. Cell. Biochem. 105: 688–698, 2008. © 2008 Wiley‐Liss, Inc.
Molecular identification and functional characterization of the vitamin C transporters expressed by Sertoli cells
Authors: Angulo Constanza , Castro Maite A. , Rivas Coralia I. , Segretain Dominique , Maldonado Rodrigo , Yañez Alejandro J. , Slebe Juan Carlos , Vera Juan Carlos , Concha Ilona I.
Published: July 2008

Vitamin C is an essential micronutrient for the development of male germ cells. In the gonad, the germ cells are isolated from the systemic circulation by the blood–testis barrier, which consists of a basal layer of Sertoli cells that communicate through an extensive array of tight junction complexes. To study the behavior of Sertoli cells as a first approach to the molecular and functional characterization of the vitamin C transporters in this barrier, we used the 42GPA9 cell line immortalized from mouse Sertoli cells. To date, there is no available information on the mechanism of vitamin C transport across the blood–testis barrier. This work describe the molecular identity of the transporters involved in vitamin C transport in these cells, which we hope will improve our understanding of how germ cells obtain vitamin C, transported from the plasma into the adluminal compartment of the seminiferous tubules. RT‐PCR analyses revealed that 42GPA9 cells express both vitamin C transport systems, a finding that was confirmed by immunocytochemical and immunoblotting analysis. The kinetic assays using radioactive vitamin C revealed that both ascorbic acid (AA) transporters, SVCT1 and SVCT2, are functionally active. Moreover, the kinetic characteristics of dehydroascorbic acid (DHA) and 3‐methylglucose (OMG) transport by 42GPA9 Sertoli cells correspond to facilitative hexose transporters GLUT1, GLUT2 and GLUT3 expressed in these cells. This data is consistent with the concept that Sertoli cells have the ability to take up vitamin C. It is an important finding and contributes to our knowledge of the physiology of male germ cells. J. Cell. Physiol. 217: 708–716, 2008. © 2008 Wiley‐Liss, Inc.
PAK1 is a novel MEK‐independent raf target controlling expression of the IAP survivin in M‐CSF‐mediated osteoclast survival
Authors: Bradley Elizabeth W. , Ruan Ming M. , Oursler Merry J.
Published: July 2008

As activation of the Ras/Raf/MEK/ERK pathway is a critical component of M‐CSF‐promoted osteoclast survival, determining specific mechanism by which M‐CSF activates this signal transduction pathway is paramount towards advancing treatment of pathological conditions resulting in increased bone turnover. The p21 activated kinase PAK1 modulates activation of the Raf/MEK/ERK pathway by either directly activating Raf or priming MEK for activation by Raf. Therefore a role for PAK1 in M‐CSF‐mediated activation of the MEK/ERK pathway controlling osteoclast survival was assessed. Here we show that PAK1 is activated by M‐CSF in a Ras‐dependent mechanism that promotes osteoclast survival. Surprisingly, PAK1 did not modulate Raf activation or Raf‐mediated MEK activation. M‐CSF mediated activation of Raf was required for PAK1 activation and osteoclast survival promoted by PAK1. This survival response was MEK‐independent as expression of constitutively active MEK did not rescue osteoclasts from apoptosis induced by blocking PAK1 function. Functionally, PAK1 promoted osteoclast survival by modulating expression of the IAP family member Survivin. M‐CSF therefore functions to promote PAK1 activation as a novel MEK‐independent Raf target to control Survivin‐mediated osteoclast survival. J. Cell. Physiol. 217: 752–758, 2008. © 2008 Wiley‐Liss, Inc.
TGF‐β induces connexin43 gene expression in normal murine mammary gland epithelial cells via activation of p38 and PI3K/AKT signaling pathways
Authors: Tacheau Charlotte , Fontaine Juliette , Loy Jennifer , Mauviel Alain , Verrecchia Franck
Published: July 2008

One of the shared physiological roles between TGF‐β and connexin family members is to inhibit epithelial cell cycle progression and consequently, to provide protection against malignant transformation. Herein, we demonstrated that TGF‐β1 induces the expression of connexin43 (Cx43) in normal murine mammary gland (NMuMG) cell lines at the protein and mRNA levels, and transcriptionally. Using overexpression of a truncated dominant‐negative form of Cx43, we determined that the modulation of gap junctional communication by TGF‐β1 plays a key role in the control of NMuMG cells proliferation by TGF‐β1. In addition, using overexpression of truncated dominant‐negative forms of either Smad2 or Smad3, and MDA‐MB‐468 human breast carcinoma cells deficient for Smad4, we determined that the Smad cascade is not implicated in TGF‐β1 effect on Cx43 expression. Using specific pharmacologic inhibitors for JNK, ERK, p38, and PI3K/AKT signaling pathways, we demonstrated the cooperative role of p38 and PI3K/AKT signaling in TGF‐β1‐induced Cx43 expression and gap junctional communication. Furthermore, transfection of a c‐jun antisense expression vector significantly prevented TGF‐β1‐induced Cx43 gene expression demonstrating the involvement of c‐Jun/AP‐1 pathway together with p38 and PI3K/AKT pathways in mediating TGF‐β1‐induced Cx43 gene expression. J. Cell. Physiol. 217: 759–768, 2008. © 2008 Wiley‐Liss, Inc.
Plasticity of growth rate and metabolism in Daphnia magna populations from different thermal habitats
Authors: Chopelet J. , Blier P.U. , Dufresne F.
Published: July 2008

The aim of this study was to evaluate the effect of temperature on growth and aerobic metabolism in clones of Daphnia magna from different thermal regimes. Growth rate (increment in size), somatic juvenile growth rate (increment in mass), and oxygen consumption were measured at 15 and 25°C in 21 clones from one northern and two southern sites. There were no significant differences in body size and growth rate (increase in length) at both 15 and 25°C among the three sites. Clones from southern site 2 had a higher mass increment than clones from the other two sites at both temperatures. Clone had a significant effect on growth (body length) and body size at both temperatures. As expected, age at maturity was lower at 25°C (4.5 days) than at 15°C, (11.6 days) and body sizes, after the release of the third clutch, were larger at 15°C than at 25°C. Northern clones had higher oxygen consumption rates and specific dynamic action (SDA) than southern clones at 15°C. By contrast, southern clones from site 1 had a higher oxygen consumption and SDA than subarctic clones at 25°C. Clones from southern site 2 had high oxygen consumption rates at both temperatures. Our results reveal important differences in metabolic rates among Daphnia from different thermal regimes, which were not always reflected in growth rate differences. J. Exp. Zool. 309A:553–562, 2008. © 2008 Wiley‐Liss, Inc.
Raldh expression in embryos of the direct developing frog Eleutherodactylus coqui and the conserved retinoic acid requirement for forelimb initiation
Authors: Elinson Richard P. , Walton Zachary , Nath Kimberly
Published: July 2008

Embryos of the direct developing frog, Eleutherodactylus coqui, provide opportunities to examine frog early limb development that are not available in species with tadpoles. We cloned two retinaldehyde dehydrogenase genes, EcRaldh1 and EcRaldh2, to see which enzyme likely supplies retinoic acid for limb development. EcRaldh1 is expressed in the dorsal retina, otic vesicle, pronephros, and pronephric duct, but not in the limb. EcRaldh2 is expressed early at the blastoporal lip and then in the mesoderm in the neurula, so this expression could function in forelimb initiation. Later EcRaldh2 is expressed in the mesoderm at the base of the limbs and in the ventral spinal cord where motor neurons innervating the limbs emerge. These observations on a frog support the functional conservation of EcRaldh2 in forelimb initiation in Osteichthyans and in limb patterning and motor neuron specification in tetrapods. J. Exp. Zool. (Mol. Dev. Evol.) 310B:588–595, 2008. © 2008 Wiley‐Liss, Inc.
Bounding χ in terms of ω and Δ for quasi‐line graphs
Authors: King Andrew D. , Reed Bruce A.
Published: July 2008

A quasi‐line graph is a graph in which the neighborhood of any vertex can be covered by two cliques; every line graph is a quasi‐line graph. Reed conjectured that for any graph G, $\chi({{G}}) \leq\left \lceil {{{1}}\over {{2}}}(\Delta({{G}})+{{1}}+\omega({{G}}))\right\rceil$ [Reed, J Graph Theory 27 (1998), 177–212]. We prove that the conjecture holds if G is a quasi‐line graph, extending a result of King et al. who proved the conjecture for line graphs [Eur J Comb 28 (2007), 2182–2187], and improving the bound of $\chi{{(}}{{G}}{{)}} \leq {3\over 2} \omega({{G}})$ given by Chudnovsky and Ovetsky [J Graph Theory 54 (2007), 41–50]. © 2008 Wiley Periodicals, Inc. J Graph Theory 59: 215–228, 2008
Solution of a conjecture of Volkmann on longest paths through an arc in strongly connected in‐tournaments
Authors: Meierling Dirk
Published: July 2008

An in‐tournament is an oriented graph such that the negative neighborhood of every vertex induces a tournament. Let m = 4 or m = 5 and let D be a strongly connected in‐tournament of order ${{n}}\geq {{2}}{{m}}-{{2}}$ such that each arc belongs to a directed path of order at least m. In 2000, Volkmann showed that if D contains an arc e such that the longest directed path through e consists of exactly m vertices, then e is the only arc of D with that property. In this article we shall see that this proposition is true for ${{m}}\geq {{4}}$, thereby validating a conjecture of Volkmann. Furthermore, we prove that if we ease the restrictions on the order of D to ${{n}}\geq {{2}}{{m}}-{{3}}$, the in‐tournament D in question has at most two such arcs. In doing so, we also give a characterization of the in‐tournaments with exactly two such arcs. © 2008 Wiley Periodicals, Inc. J Graph Theory 60: 130–148, 2009
Synthesis of [14C] ‐ and [13C6]‐labeled tipranavir and its potential hydroxyl metabolite and the glucuronide conjugate
Authors: Latli Bachir , Hrapchak Matt , Easter John A. , Stolle Wayne T. , Grozinger Karl , Krishnamurthy Dhileepkumar , Senanayake Chris H.
Published: July 2008

Tipranavir or Aptivus®is a non‐peptidic protease inhibitor approved for the combination treatment with ritonavir of HIV infection. Tipranavir labeled with radioactive and stable isotopes of carbon was required for drug metabolism (excretion, distribution, and absorption) studies and to develop bioanalytical methods needed for the support of clinical studies. [7‐14C]‐Benzoic acid and uniformly labeled benzoic acid (ring‐13C699 at%13C) were used to prepare [14C]‐ and [13C6]‐labeled tipranavir, respectively. Radioactively labeled tipranavir was prepared with a specific activity of 54 mCi/mmol (2GBq/mmol); it was necessary to dilute its specific activity with unlabeled tipranavir to 28 mCi/mmol (46.45 µCi/mg) because of its instability. TheN‐hydroxyl metabolite (12) and the glucuronide conjugate (13), the most abundant metabolites of tipranavir (when administered in conjunction with ritonavir) were also synthesized. Copyright © 2008 John Wiley & Sons, Ltd.
Enzymatic synthesis of phenylpyruvic acid labeled with deuterium, tritium, and carbon‐14
Authors: Skowera Katarzyna , Kańska Marianna
Published: July 2008

The synthesis of isotopomers of phenylpyruvic acid, PPA, selectively labeled with hydrogen isotopes in the 3‐position of the side‐chain is reported. Three deuterium or tritium labeled isotopomers of L‐phenylalanine, L‐Phe, i.e. [(3S)‐2H]‐L‐, [(3S)‐3H]‐L‐, and doubly labeled [(3S)‐2H/3H]‐L‐Phe were synthesized using the enzyme phenylalanine ammonia lyase (EC 4.3.1.5). In the second step these isotopomers of L‐Phe were converted into [(3S)‐2H], [(3S)‐3H]‐, and [(3S)‐2H/3H]‐isotopomers of PPA using the enzyme L‐phenylalanine dedydrogenase (EC 1.4.1.20). The isotopomer of PPA labeled with 14C in carboxylic group, [1‐14C]‐PPA, was obtained in a two‐step enzymatic reaction using [1‐14C]‐cinnamic acid as the starting substrate. Copyright © 2008 John Wiley & Sons, Ltd.
Retracted: Leadership behaviors that really count in an organization's performance in the middle east: The case of Dubai
Authors: Behery Mohamed H.
Published: July 2008

Retraction: The following article from the Journal of Leadership Studies entitled “Leadership behaviors that really count in an organization's performance in the Middle East: The case of Dubai” by Mohamed Behery, published on July 28, 2008, on Wiley Online Library (wileyonlinelibrary.com) and in Volume 2, Issue 2 (August 2008), has been retracted by agreement between the author, the Editor, Jake Burdick, and Wiley Periodicals, Inc.

The Editorial Office of the Journal of Leadership Studies has concluded that the article did not contain precise references to support direct quotations and significant paraphrases from other articles. Although the Editorial Office felt a retraction was necessary, it wishes to note its belief that the author acted in good faith and that Mr. Behery has not been accused of any misconduct with respect to the contents of the article.

Jeremy Moreland

Editor‐in‐Chief, Journal of Leadership Studies

Jake Burdick

Editor, Journal of Leadership Studies
Leadership competencies: An exploratory study of what is important now and what has changed since the terrorist attacks of 9/11
Authors: Sparks Taylor E. , Gentry William A.
Published: July 2008

This exploratory study attempts to identify the leadership competencies that managers believe are needed to be successful across different managerial levels and organization types (manufacturing, finance, insurance, and banking, health, transportation, communications, and utilities, wholesale and retail trade, private nonprofit, and public) and presents an analysis of whether changes in the importance of certain leadership competencies over time coincided with the 9/11 terrorist attacks in the United States. Our findings suggest that the leadership competencies leading employees and resourcefulness were the most important across all managerial levels and organization types studied. Moreover, leadership competencies important (or not important) for one managerial level or organization type seem to be important (or not important) for others. Furthermore, leadership competencies important before 9/11 remained important immediately after 9/11, 2 years after 9/11, and are still important today. These findings may have implications for leadership training and development, selection, and succession planning.
Content analysis of leadership in Asia‐Pacific organizations
Authors: Chiu Darson , Lao Teresa M.
Published: July 2008

Leadership and management are important factors that influence the ability of organizations to fulfill their goals. In this article, the role of two organizations was analyzed to determine which leadership styles are appropriate. The Asia‐Pacific Economic Cooperation (APEC) and the Pacific Economic Cooperation Council (PECC) are two international organizations in the region of Asia‐Pacific with similar goals but dissimilar organizational natures, properties, functions, and structures. Past studies researching APEC and PECC have mainly taken the perspective of macroeconomics or international relations. The intent when carrying out this study was to adopt a nontraditional approach to studying APEC and PECC by using a qualitative leadership and management methodology. By referring to identified leadership practices through content analysis and explored organizational paradigms through a narrative approach, this study recommends the application of suitable leadership and management practices to empower these two organizations and other similar organizations in the United States and other countries.
Examining relationships between director leadership practices and manager worklife and burnout
Authors: Lee How , Cummings Greta G.
Published: July 2008

Managers are subject to high stress and burnout in their demanding roles, so addressing their worklife and level of burnout is important to retain leadership in healthcare organizations. The purpose of this study was to examine the relationship between the observed leadership style of directors and the worklife and burnout of healthcare managers. A secondary analysis of data from 176 leaders in five different managerial cohorts within a provincial cancer agency was conducted using multiple regression and MANCOVA analysis. The study used data collected from the Worklife Improvement and Leadership Development study in 2006, the Kouzes and Posner Leadership Practices Inventory, the Maslach Burnout Inventory, and the Areas of Worklife Survey. Findings indicate the importance of transformational leadership styles to empower managers. Directors may improve the worklife of managers by using transformational leadership practices to address the amount of control and appropriateness of rewards to positively influence the job satisfaction of managers.
Leader‐member exchangeand job satisfacton: Cross‐industry comparisons and predicted employee turnover
Authors: Mardanov Ismatilla T. , Maertz Carl P. , Sterrett Jack L.
Published: July 2008

The present research analyzes quality of leader‐member exchange (LMX) and job satisfaction and predicts employee turnover rates in the food manufacturing, restaurant, and banking industries resulting from low‐quality LMX and job dissatisfaction. It confirms the reliability and construct validity of the well‐known LMX scale and Minnesota Job Satisfaction Questionnaire (MSQ) in cross‐industry comparisons. It also identifies the shape of the hypothesized relationships among the three industries. Comparisons indicate that in the service sector, quality of LMX is significantly higher than in manufacturing, that the level of job satisfaction is higher in manufacturing than in service, and that satisfaction with supervision has a significant impact on job satisfaction.
Creating and sustaining a strategic partnership: A model for human resource development
Authors: Peterson Shari L.
Published: July 2008

Human resource development (HRD) leaders have been challenged to become strategic business partners in order to link people, strategy, and performance. In spite of a critical need, there has not been an empirically testable systemic framework that pulls together the wide variety of strategic imperatives that have been suggested. This article presents a conceptual model identifying the essential system elements that provide a framework for how HRD might create and then sustain its full leadership potential as a strategic partner.
Characterization of atherosclerotic plaque of carotid arteries with histopathological correlation: Vascular wall MR imaging vs. color Doppler ultrasonography (US)
Authors: Watanabe Yuji , Nagayama Masako , Suga Tsuyoshi , Yoshida Kazumichi , Yamagata Sen , Okumura Akira , Amoh Yoshiki , Nakashita Satoru , Van Cauteren Marc , Dodo Yoshihiro
Published: July 2008

Purpose

To investigate whether the vessel wall MRI of carotid arteries would differentiate at‐risk soft plaque from solid fibrous plaque by identifying liquid components more accurately than color Doppler ultrasonography (US).

Materials and Methods

This study included 54 carotid arteries in 54 consecutive patients who underwent carotid endarterectomy. MRI was performed using black‐blood fat‐suppressed (FS) T1‐and FS T2‐weighted TSE sequences. A total of 68 major segments of the 54 carotid plaques were grouped into four MR categories based on signal intensity index (SII). MR criteria used for the diagnosis of plaque vulnerability were: at‐risk soft plaque including a segment of liquid component (category A or B), solid fibrous plaque (category C or D). The MR and US findings were compared with histopathological findings of endarterectomy specimens.

Results

Intraoperative findings and microscopic examination of endarterectomy specimens revealed 24 at‐risk soft plaques and 30 solid fibrous plaques. The sensitivity, specificity, and accuracy for diagnosing at‐risk soft plaque are 96%, 93%, and 94% for MR, and 75%, 63%, and 69% for color Doppler US, respectively. The slice‐by‐slice MR evaluation of carotid wall also revealed detailed information of plaque segments and correlated well with the features of corresponding histologic sections.

Conclusion

Vessel wall MRI with MRI category could have a potential to more accurately diagnose an at‐risk soft plaque predominantly composed of liquid components in comparison with color Doppler US. J. Magn. Reson. Imaging 2008;28:478–485. © 2008 Wiley‐Liss, Inc.
Segmented echo planar MR imaging of the brachial plexus with inversion recovery magnetization preparation at 3.0T
Authors: Zhang Zhongwei , Song Laijing , Meng Quanfei , Li Ziping , Luo Boning , Pei Zhong , Zeng Jinsheng
Published: July 2008

Purpose

To evaluate the image quality of segmented echo planar MRI with inversion recovery magnetization preparation (seg‐IR‐EPI) to depict the anatomy and pathologic changes involving the brachial plexus.

Materials and Methods

The coronal seg‐IR‐EPI sequence was performed on 30 healthy volunteers and 20 patients. Postprocessing techniques were used to generate images of brachial plexus and the images acquired were qualitatively evaluated by two experienced radiologists based on grading of the morphological images. Signal‐to‐noise ratios (SNRs) and nerve soft tissue contrast‐to‐noise‐ratios (CNRs) were calculated and the normalized SNR (SNRn) and the normalized CNR (CNRn) were compared with the STIR TSE sequence.

Results

Although seg‐IR‐EPI had more ghosting artifacts than STIR TSE, excellent general image appearance with minor blurring can be achieved with seg‐IR‐EPI. In all healthy volunteers the means of CNRn were significantly greater for seg‐IR‐EPI than for STIR‐TSE, while the means of SNRn were significantly lower for seg‐IR‐EPI than for STIR‐TSE.

Conclusion

In the present study the seg‐IR‐EPI sequence obtained uniform fat suppression and high‐contrast T2‐weighted images of brachial plexus. Our data suggest that the seg‐IR‐EPI sequence may provide high fidelity in evaluating brachial plexus. J. Magn. Reson. Imaging 2008;28:440–444. © 2008 Wiley‐Liss, Inc.
Comparison of the reproducibility of quantitative cardiac left ventricular assessments in healthy volunteers using different MRI scanners: A multicenter simulation
Authors: Gandy Stephen J. , Waugh Shelley A. , Nicholas R. Stephen , Simpson Helen J. , Milne Wendy , Houston J. Graeme
Published: July 2008

Purpose

To derive reproducibility assessments of ejection fraction (EF) and left ventricular mass (LVM) from short‐axis cardiac MR images acquired at single and multiple time‐points on different 1.5T scanner models.

Materials and Methods

Images of 15 healthy volunteers were acquired twice using a Magnetom Avanto scanner (Siemens, Erlangen, Germany) and once using a Signa Excite scanner (General Electric, Milwaukee, WI, USA) over four months, and analyzed using ARGUS and MASS Analysis+ software, respectively. Two physicists independently segmented the myocardial borders in order to derive intra‐ and interobserver assessments of EF and LVM for single and multiple time‐points on the same and different scanners.

Results

For EF, the coefficient of repeatability (CoR) increased as different observers, multiple time‐points, and different scanners were introduced. The CoR ranged from 2.8% (intraobserver measurements, single time‐point, same scanner) to 10.0% (interobserver measurements, different time‐points, different scanners). For LVM, intraobserver CoR parameters were consistently smaller than interobserver values. The CoR ranged from 7.8 g (intraobserver measurements, single time‐point, same scanner) to 39.5 g (interobserver measurements, different time‐points, different scanners).

Conclusion

Reproducible EF data can be obtained at single or multiple time‐points using different scanners. However, LVM is notably susceptible to interobserver variation, and this should be carefully considered if similar evaluations are planned as part of multicenter or longitudinal investigations. J. Magn. Reson. Imaging 2008;28:359–365. © 2008 Wiley‐Liss, Inc.
A survey of the potential impact of the European Union Physical Agents Directive (EU PAD) on electromagnetic fields (EMF) on MRI research practice in the United Kingdom
Authors: Perrin Nicola M.R. , Morris Clive J.
Published: July 2008

Purpose

To assess concerns that the European Union Physical Agents Directive (EU PAD) on Electromagnetic Fields (EMF) could seriously restrict the use of MRI for research, diagnosis, and treatment, this study was conducted to examine the impact of the EU PAD on research practice, following a previous survey that assessed its impact on clinical practice.

Materials and Methods

Data were collected through an online survey. E‐mail invitations were sent to every UK grant‐holder funded by Cancer Research UK, Engineering and Physical Sciences Research Council (EPSRC), Medical Research Council (MRC), and the Wellcome Trust in the last three years, who use MRI technology.

Results

A total of 70% of researchers responding to the survey reported that some of their MR research is conducted with at least one researcher in the scanner room during operation. Of those researchers in the scanner room, more than three‐quarters are within 1 m of the scanner, for any scanner strength, and would therefore exceed the limits set in the Directive. Over half of these researchers also reach into the magnet bore, while at least one in five researchers spend over an hour in the scanner room during operation.

Conclusion

The results suggest the EU PAD could have a very prohibitive impact on research practice. The current exposure limits would prohibit interventional MRI, limit the provision of patient care, and restrict researchers from reaching into the magnet bore to position and check equipment or to provide technical support. The use of new, more powerful high‐field scanners will be particularly restricted. J. Magn. Reson. Imaging 2008;28:486–492. © 2008 Wiley‐Liss, Inc.
Intracoronary MR imaging using a 0.014‐inch MR imaging‐guidewire: Toward MRI‐guided coronary interventions
Authors: Qiu Bensheng , Gao Fabao , Karmarkar Parag , Atalar Ergin , Yang Xiaoming
Published: July 2008

Purpose

To validate the feasibility of using a newly designed MR imaging‐guidewire (MRIG) to guide angioplasty balloon placement in coronary arteries.

Materials and Methods

A custom gold/sliver/Nitinol/MP35N‐based, 0.014‐inch MRIG was manufactured. To test its mechanical performance we used the new MRIG to catheterize the left coronary arteries of three dogs under x‐ray fluoroscopy. To further validate the feasibility of using the MRIG to generate intracoronary MR imaging, we positioned the MRIG, along with a dilation‐perfusion balloon catheter, into the left coronary arteries of an additional three dogs. Longitudinal and four‐chamber views of cine cardiac MR images were obtained using a fast gradient recalled echo (FGRE) sequence (TR/TE/FA = 5.2 msec/1.6 msec/20°, field of view [FOV] = 32 × 32 cm, thickness = 5 mm, space = 2 mm, matrix = 256 × 160, number of excites [NEX] = 0.5, and bandwidth [BW] = 32 kHz). Then three‐dimensional (3D) MR coronary angiography of the left coronary arteries was obtained using a fast imaging employing steady‐state acquisition (FIESTA) sequence. We subsequently used the MRIG, at a receive‐only mode, to generate intracoronary MR images using FGRE (TR/TE/FA = 7.2 msec/3.5 msec/20°, FOV = 18 × 18cm, thickness = 3 mm, space = 0.5 mm, matrix = 256 × 256, NEX = 0.5, and BW = 32 kHz).

Results

In all six animals the left main coronary arteries were successfully catheterized. 3D MR imaging displayed left coronary artery branches. Intracoronary MR imaging demonstrated the inflated balloons as a “train track” or a bright, thick ring at different views.

Conclusion

This study demonstrates the potential of using this newly designed gold/sliver/Nitinol/MP35N‐based, 0.014‐inch MRIG to catheterize coronary arteries and, thus, generate intracoronary MR imaging with balloon inflation. J. Magn. Reson. Imaging 2008;28:515–518. © 2008 Wiley‐Liss, Inc.
Metabolite signature of developmental foregut cyst on in vivo and in vitro 1H MR spectroscopy
Authors: Santhosh Kannath , Thomas Bejoy , Varma Luxmi , Sandhyamany S. , Kesavadas Chandrasekharan , Appukuttan P.S. , Srinivas G. , Gupta Arun Kumar , Kapilamoorthy T.R. , Unnikrishnan M.
Published: July 2008

Foregut duplication cysts are developmental anomalies of the bronchopulmonary foregut and are common cystic lesions of the mediastinum. We describe a case of mediastinal foregut duplication cyst with in vivo 1H MR spectroscopy on a 1.5T magnet showing a large metabolite peak at 2.02 ppm, attributable to N‐acetylated compounds, in addition to a smaller peak at 1.33 ppm, considered to represent lipids. In vitro NMR spectroscopy (7.05T) of cyst fluid confirmed the presence of these peaks. In addition, a broad multiplet centered at 3.7 ppm, possibly from various protons of the hexose ring system, was also noted. Chemical analysis of the cyst fluid demonstrated the presence of N‐acetylhexosamines, proteins, and lipids. Again, in vitro spectra of pure samples of N‐acetylglucosamine and N‐acetylgalactosamine were obtained for comparison, which better resolved the N‐acetyl peak and the peaks at 3.7 ppm. The mucus secreted by respiratory epithelium and the mucous glands of the foregut cysts contains glycoproteins that have N‐acetylhexosamines as components and lipid breakdown products that are thought to contribute to the observed spectrum. This information might be useful in predicting the cyst content and, in turn, the lining of the epithelium and the glandular elements. J. Magn. Reson. Imaging 2008;28:493–496. © 2008 Wiley‐Liss, Inc.
Simultaneous estimation of tongue volume and fat fraction using IDEAL‐FSE
Authors: Humbert Ianessa A. , Reeder Scott B. , Porcaro Eva J. , Kays Stephanie A. , Brittain Jean H. , Robbins JoAnne
Published: July 2008

Purpose

To determine whether high‐resolution, high signal‐to‐noise ratio (SNR) images of the tongue acquired with IDEAL‐FSE (iterative decomposition of water and fat with echo asymmetry and least squares estimation) will provide comparable volumetric measures to conventional nonfat‐suppressed FSE imaging and to determine the feasibility of estimating the proportion of lingual fat in adults using IDEAL‐FSE imaging.

Materials and Methods

Healthy volunteers underwent magnetic resonance imaging of the tongue using both IDEAL‐FSE and conventional FSE sequences. The tongue was manually outlined to derive both volumetric and fat fraction measures. Intraclass correlation coefficients (ICCs) were computed for intrarater measurement reliability and Spearman's rank correlation tested the relationship between IDEAL‐FSE and conventional volumetric measures of the tongue.

Results

IDEAL‐FSE imaging yielded almost identical volumetric measures to that of conventional FSE imaging in the same amount of scan time (IDEAL‐FSE mean 64.1 cm3; conventional mean 63.3 cm3; r = 0.988, P ≤ 0.01). The average fat signal fraction across participants was 26.5%. Intrarater reliability was excellent for all measures (ICC ≥ 0.92).

Conclusion

Our results indicate that IDEAL‐FSE provided similar lingual volume estimates to conventional FSE imaging obtained in both the current and previous studies. IDEAL‐FSE measures of lingual fat composition may be useful in studies that aim to increase lingual muscle strength and volume in swallowing and speech‐disordered populations. J. Magn. Reson. Imaging 2008;28:504–508. © 2008 Wiley‐Liss, Inc.
MR‐guided direct arthrography of the hip
Authors: Graves Martin J. , Wakely Suzanne , Bearcroft Philip W. , Black Richard T. , van Rooyen Elzare , Soh Edmund , Lomas David J.
Published: July 2008

Purpose

To develop an MR‐guided technique for direct magnetic resonance arthrography (DMRA) of the hip using a conventional 1.5 Tesla (T) MRI scanner.

Materials and Methods

Interactive versions of standard single‐shot fast spin echo, coherent gradient echo, and fully balanced steady‐state free precession sequences were developed, together with the ability to operate the scanner from within the magnet room. Initial optimization was performed using ex vivo animal joints. After informed consent, five patients underwent DMRA using dilute gadolinium as the contrast medium.

Results

The procedure was successful in all five patients and diagnostic quality MR arthrography studies were obtained in all cases. The time taken from the initial placement of skin marker to the introduction of contrast medium reduced with successive patients: 26, 22, and 19 min with the final two studies taking 13 min each.

Conclusion

This work demonstrates the feasibility of performing DMRA using MR guidance, avoiding the need for X‐ray fluoroscopy facilities but exploiting the available imaging performance of a high‐field closed‐bore MR system. The use of an in room control and display system together with interactive fluoroscopic imaging sequences simplifies the positioning of the needle and allows rapid confirmation of an intra‐articular injection. J. Magn. Reson. Imaging 2008;28:462–465. © 2008 Wiley‐Liss, Inc.
MR susceptibility weighted imaging (SWI) complements conventional contrast enhanced T1 weighted MRI in characterizing brain abnormalities of Sturge‐Weber Syndrome
Authors: Hu Jiani , Yu Yingjian , Juhasz Csaba , Kou Zhifeng , Xuan Yang , Latif Zahid , Kudo Kohsuke , Chugani Harry T. , Haacke E. Mark
Published: July 2008

Purpose

To evaluate the efficacy of susceptibility weighted imaging (SWI) in comparison to standard T1 weighted postgadolinium contrast (T1‐Gd) MRI in patients with Sturge‐Weber Syndrome (SWS).

Materials and Methods

Twelve children (mean age, 5.6 years) with the diagnosis of SWS and unilateral hemispheric involvement were recruited prospectively and examined with high resolution three dimensional SWI and conventional T1‐Gd. Both SWI and T1‐Gd images were evaluated using a four‐grade scoring system according to six types of imaging findings (enlargement of transmedullary veins, periventricular veins, and choroid plexus, as well as leptomeningeal abnormality, cortical gyriform abnormality, and gray matter/white matter junctional abnormality). The scores of SWI versus T1‐Gd images were then compared for each type of abnormality.

Results

SWI was superior to T1‐Gd in identifying the enlarged transmedullary veins (P = 0.0020), abnormal periventricular veins (P = 0.0078), cortical gyriform abnormalities (P = 0.0020), and gray matter/white matter junction abnormalities (P = 0.0078). Conversely, T1‐Gd was better than SWI in identifying enlarged choroid plexus (P = 0.0050) and leptomeningeal abnormalities (P = 0.0050).

Conclusion

SWI can provide useful and unique information complementary to conventional contrast enhanced T1 weighted MRI for characterizing SWS. Therefore, SWI should be integrated into routine clinical MRI protocols for suspected SWS. J. Magn. Reson. Imaging 2008;28:300–307. © 2008 Wiley‐Liss, Inc.
Quantitative assessment of bone marrow edema‐like lesion and overlying cartilage in knees with osteoarthritis and anterior cruciate ligament tear using MR imaging and spectroscopic imaging at 3 Tesla
Authors: Li Xiaojuan , Ma Benjamin C. , Bolbos Radu I. , Stahl Robert , Lozano Jesus , Zuo Jin , Lin Katrina , Link Thomas M. , Safran Marc , Majumdar Sharmila
Published: July 2008

Purpose

To quantitatively assess bone marrow edema‐like lesion (BMEL) and the overlying cartilage in osteoarthritis (OA) or anterior cruciate ligament (ACL)‐injured knees using magnetic resonance imaging (MRI) and spectroscopic imaging (MRSI).

Materials and Methods

Eight healthy controls and 30 patients with OA and other injuries who showed BMEL were scanned at 3.0T. A regression model was constructed to automatically calculate the volume of BMEL. Normalized T1ρ z‐scores were calculated within BMEL‐overlying cartilage. Three‐dimensional (3D) MRSI was acquired in the BMEL and surrounding bone marrow.

Results

The mean T1ρ z‐score was significantly higher in BMEL‐overlying cartilage than that in surrounding cartilage in the lateral tibia of patients with ACL tears (P < 0.001). Significantly elevated water and unsaturated lipids, and decreased saturated lipids were observed in BMEL. The volume of elevated water correlated with the volume of BMEL. Water content was significantly higher within BMEL than that outside BMEL. The unsaturation index outside BMEL was significantly higher in patients with ACL tears than that in OA.

Conclusion

3D MRSI and T1ρ mapping provide tools to quantitatively evaluate BMEL in OA and knee injury. This may allow us to better understand pathophysiology and evolution of injuries and degenerative conditions of the knee. J. Magn. Reson. Imaging 2008;28:453–461. © 2008 Wiley‐Liss, Inc.
Free‐breathing 3D steady‐state free precession coronary magnetic resonance angiography: Comparison of diaphragm and cardiac fat navigators
Authors: Nguyen Thanh D. , Spincemaille Pascal , Cham Matthew D. , Weinsaft Jonathan W. , Prince Martin R. , Wang Yi
Published: July 2008

Purpose

To compare the performance of the conventional diaphragm navigator (DNAV) and the recently developed cardiac fat navigator (FatNAV) in suppressing respiration‐induced cardiac motion in free‐breathing 3D balanced steady‐state free precession coronary MRA (SSFP CMRA).

Materials and Methods

In 16 healthy volunteers the right coronary artery (RCA) was imaged at 1.5T using a navigator‐gated 3D SSFP CMRA sequence. DNAV and FatNAV gating were performed in random order. Image quality difference was scored by three experienced readers blinded to the gating technique. Blood signal‐to‐noise ratio (SNR), blood‐to‐myocardium contrast‐to‐noise ratio (CNR), and navigator efficiency were calculated.

Results

Diagnostically interpretable CMRA was obtained successfully in all 16 subjects with FatNAV gating (0% failure rate) and only 14 subjects with DNAV gating (12% failure rate). Compared to DNAV gating, FatNAV gating provided similar SNR and CNR, better image quality (P < 0.01), and 28% improvement in navigator efficiency (P = 0.002).

Conclusion

FatNAV gating provides more effective motion suppression and better image quality than DNAV gating for free‐breathing 3D SSFP CMRA of the RCA in healthy subjects. J. Magn. Reson. Imaging 2008;28:509–514. © 2008 Wiley‐Liss, Inc.
Monitoring infection and inflammation in murine models of cystic fibrosis with magnetic resonance imaging
Authors: Sheth Vipul R. , van Heeckeren R. Christiaan , Wilson Alma G. , van Heeckeren Anna M. , Pagel Mark D.
Published: July 2008

Purpose

To evaluate magnetic resonance imaging (MRI) in assessing lung inflammation longitudinally in genetic mouse models of cystic fibrosis (CF). MRI is used to view soft tissues noninvasively, but the lung is challenging to image.

Materials and Methods

Cftr+/+ (wildtype) and Cftr−/− (CF) mice were inoculated with agarose beads laden with Pseudomonas aeruginosa. Longitudinal MR lung images were acquired with cardiac gating. The effects of echo time and respiration gating were evaluated to improve the detection of lung inflammation.

Results

Cardiac gating and signal averaging sufficiently suppressed motion artifacts without requiring respiration gating. MRI detected moderate to severe inflammation in infected mice, which was confirmed by histology results.

Conclusion

In vivo longitudinal MRI methods can assess lung inflammation in P. aeruginosa‐infected mice, which obviates serial sacrifice. MRI was able to detect inflammation in the absence of other physiological symptoms. J. Magn. Reson. Imaging 2008;28:527–532. © 2008 Wiley‐Liss, Inc.
Single breath‐hold multiarterial dynamic MRI of the liver at 3T using a 3D fat‐suppressed keyhole technique
Authors: Hong Hye‐Suk , Kim Hua Sun , Kim Myeong‐Jin , De Becker Jan , Mitchell Donald G. , Kanematsu Masayuki
Published: July 2008

Purpose

To evaluate the feasibility of single breath‐hold, multiarterial MRI of the liver using the THRIVE‐CENTRA‐keyhole technique.

Materials and Methods

Twenty‐eight patients with 63 focal hepatic lesions underwent liver MR examinations that included the three‐dimensional THRIVE‐CENTRA‐keyhole sequence. Three or six phases were obtained for arterial phase scanning during a single breath‐hold. Central k‐space data were collected for each phase but the remaining peripheral k‐space data were collected only once. The enhancement pattern of each hepatic lesion was analyzed according to the specific diagnosis.

Results

Hepatocellular carcinomas (n = 24) enhancement patterns included: rim enhancing (n = 9), homogeneous (n = 7), nodule‐in‐nodule (n = 5), or heterogeneous (n = 3). A late peritumoral rim was observed in four (17%) of the hepatocellular carcinomas. Most metastases (17 of 18; 94%) demonstrated peripheral rim enhancement. The progressive centripetal enhancement of hemangiomas (n = 6) was clearly depicted. Focal nodular hyperplasia (n = 4) showed early homogeneous enhancement and one lesion demonstrated a central scar.

Conclusion

The THRIVE‐CENTRA‐keyhole technique can be used to acquire single breath‐hold, multiarterial images depicting improved enhancement characteristics of focal hepatic lesions. This technique will allow accurate timing of arterial scanning with 3D acquisition and high temporal resolution. J. Magn. Reson. Imaging 2008;28:396–402. © 2008 Wiley‐Liss, Inc.
Comparison of different contrast agents and doses for quantitative MR myocardial perfusion imaging
Authors: Köstler Herbert , Ritter Christian , Lipp Michael , Beer Meinrad , Hahn Dietbert , Sandstede Jörn
Published: July 2008

Purpose

To investigate three different contrast agents at different injection volumes for repetitive quantitative multislice myocardial perfusion imaging using the prebolus technique.

Materials and Methods

Two consecutive prebolus perfusion measurements were performed on a 1.5T scanner using identical injection volumes for the first and second examination to test the reproducibility for possible rest and stress examination in normal volunteers. Either 1–8 mL, 1–12 mL Gd‐DTPA, 1–4 mL, 1–6 mL, 1–9 mL Gd‐BOPTA, or 1–4 mL, 1–6 mL gadobutrol were applied.

Results

In cases where injection volumes were sufficiently small, there was no indication of significant differences in quantitative perfusion values with respect to the different contrast agents. Increasing the bolus volume improved the contrast‐to‐noise ratio (CNR) but led to saturation effects and underestimation of the true perfusion. The highest CNR was measured for gadobutrol (6 mL, p < 0.0005 compared to 8 mL Gd‐DTPA). The smallest difference of perfusion values between the first and the second prebolus examination was found for Gd‐BOPTA (p ≤ 0.006 compared Gd‐DTPA).

Conclusion

Prebolus examinations for quantitative myocardial perfusion imaging are possible with all three contrast agents for sufficient small injection volumes. Gd‐BOPTA was found to be advantageous for a combined quantitative rest and stress examination. J. Magn. Reson. Imaging 2008;28:382–389. © 2008 Wiley‐Liss, Inc.
Heschl gyrus and its included primary auditory cortex: Structural MRI studies in healthy and diseased subjects
Authors: Abdul‐Kareem Ihssan A. , Sluming Vanessa
Published: July 2008

Despite the fact that the Heschl gyrus (HG) is a crucial brain structure as it contains the primary auditory cortex (PAC), relatively few structural MRI studies have concentrated upon it. We propose that this may be attributed in part to the considerable variability of this structure and, most importantly, to the lack of unified criteria for defining the extent of the PAC along the MRI‐determined landmarks of the HG, which ultimately affects the reliability and reproducibility of these studies. This review highlights three aspects: first, the standard and variant anatomy of the HG and PAC with particular focus on MRI definition of these regions; second, the importance of studying the HG and PAC in health and disease using structural MRI; and, third, the problem of MRI localization of the PAC. The scientific community should be aware that the HG and its included PAC are not synonyms. Additionally, owing to the great complexity and variability of these regions, future MRI studies should be cautious when using single brain‐based atlas or maps generated by simply averaging across individuals to localize these regions. Instead, and while waiting for future in vivo microstructural localization of the PAC, the use of probabilistic and functional maps is advantageous but not without shortcomings. J. Magn. Reson. Imaging 2008;28:287–299. © 2008 Wiley‐Liss, Inc.