bluuebunny/crossref_metadata_2025 huggingface dataset:
Histological alterations following thyroid fine needle biopsy: A systematic review
Authors: Polyzos Stergios A. , Patsiaoura Kalliopi , Zachou Konstantia
Published: March 2009

Thyroid fine‐needle biopsy (FNB) is a simple, reliable, inexpensive, and generally safe diagnostic procedure in the management of thyroid nodules. However, the trauma inflicted by the needle may lead to various degrees of histological alterations, observed in histological specimens, if thyroidectomy follows. Post‐FNB histological alterations of the thyroid (PFHAT) can generally be divided into acute and chronic. Hemorrhage is the most common acute and fibrosis the most common chronic PFHAT. Some of the PFHAT causes problems in histological assessment, making diagnosis difficult, even leading to misdiagnosis. In this review, we tried to collect and summarize all reported PFHAT cases and studies, aiming to make involved physicians, cytologists, and pathologists aware of the spectrum of PFHAT and to provide information to help in differential diagnosis and to avoid misdiagnoses, which could lead to unnecessary radical surgery and/or adjuvant therapy. Diagn. Cytopathol. 2009. © 2009 Wiley‐Liss, Inc.
Evaluation of aspiration cytology of the liver space occupying lesions by simultaneous examination of smears and cell blocks
Authors: Khurana Ujjawal , Handa Uma , Mohan Harsh , Sachdev Atul
Published: March 2009

This study was undertaken to compare the efficacy of cytologic smears and histological sections from cell blocks in diagnosis of space occupying lesions (SOLs) of the liver and to classify the lesions on the basis of combined cytohistologic diagnosis. The study was conducted on 50 patients who had radiologically detected SOL/SOLs in the liver and ultrasound‐guided fine needle aspiration of liver was done. In all the cases, both smears and cell blocks were made. Forty‐seven cases were diagnosed as malignant and three as benign on both cytologic smears and cell blocks. Hepatocellular carcinoma was diagnosed in 8 (16%) cases and metastasis in 39 (78%) cases. The subtyping of malignancy could not be done on 11 (22%) cytologic smears and 8 (16%) cell block sections. However, on combined cytohistologic correlation, 17 (34%) out of these 19 (38%) cases could be subtyped. Sensitivity of cytologic smears and cell blocks in subtyping of malignancy was 72.3% and 82.9%, respectively. Combined cytohistologic diagnosis was found to be significantly better than isolated cytologic and cell block diagnosis (P ≤ 0.05). To conclude, FNA of the SOLs of the liver is an effective procedure for diagnosing malignancy. However, cytological examination alone may fail to pinpoint the type of the tumor. Concomitant examination of cell block not only confirms the malignancy but also helps in subtyping it. Diagn. Cytopathol. 2009. © 2009 Wiley‐Liss, Inc.
Comparative analysis of immunoglobulin polymerase chain reaction and flow cytometry in fine needle aspiration biopsy differential diagnosis of non‐Hodgkin B‐cell lymphoid malignancies
Authors: Maroto Alicia , Martinez Manuel , Martinez Miguel Angel , de Agustin Pedro , Rodriguez‐Peralto Jose Luis
Published: March 2009

Single primer pair polymerase chain reaction (PCR) assays for the detection of clonal immunoglobulin heavy chain (IgH) gene rearrangements and immunophenotyping by flow cytometry have been proved as useful techniques in the diagnosis of lymphoid disorders in fine needle aspirates. However, a comparative analysis of both ancillary techniques in the same samples has not been previously performed. To compare the sensitivity of flow cytometry and PCR techniques, we made a wide prospective study of 77 fine needle aspiration biopsy (FNAB) samples from lymph nodes and extranodal lymphoid infiltrates. The adjunctive values of a single primer pair PCR amplification of IgH genes and of the immunophenotyping by flow cytometry were evaluated comparing their results with the final clinicopathological diagnosis of each patient supported by histological features and clinical follow up. Among the 24 B‐cell non‐Hodgkin lymphomas, monoclonal IgH bands were detected in 22 cases by PCR, and 21 cases were correctly considered B‐cell lymphoma by flow cytometry. A monoclonal IgH band was also detected in 1 of the 53 reactive lymphoid disorders. When both ancillary techniques were combined with morphological findings, 23 of the 24 B‐cell lymphomas were correctly diagnosed but one reactive lymphoid disorder was also considered a B‐cell lymphoma. We demonstrate a similar level of detection of B‐cell lymphomas by single round PCR and flow cytometry techniques, and a strong adjunctive value when combined with morphological findings to diagnose correctly lymphoproliferative disorders by FNAB. However, we must be cautious with PCR results since false‐positive cases can occur. Diagn. Cytopathol. 2009. © 2009 Wiley‐Liss, Inc.
Combining fine needle aspiration with brushing cytology has improved yields in diagnosing pancreatic ductal adenocarcinoma
Authors: Jing Xin , Wamsteker Erik‐Jan , Li Hong , Pu Robert T.
Published: March 2009

The aim of this retrospective study is to evaluate the diagnostic yields of combining fine needle aspiration (FNA) with brushing cytology (BC) in clinical work‐up of pancreatic ductal adenocarcinoma.

The study included a total of 97 patients who underwent both FNA and BC along with histologic/clinical follow‐up (F/U). Cytologic diagnoses were categorized as negative for neoplasm (NEG), atypical/favor neoplasm (AN), and suspicious or positive for neoplasm (POS). Based on the cytologic diagnoses, the cohort was divided as follows: 23 had concordant FNA and BC diagnoses of POS/AN, all were neoplasms on F/U; 34 had disconcordant (POS/AN vs. NEG) FNA and BC diagnoses, all but 2 were neoplasms on F/U; The remaining 40 were NEG on both FNA and BC, F/U revealed that 10 were neoplasms and 30 were chronic pancreatitis. Overall, FNA rendered more true positive diagnoses than BC. However, BC but not FNA detected neoplasms in 10 patients. Most of the neoplasms identified on F/U were ductal adenocarcinoma (59 of 65). Diagnostic sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 69.2, 93.8, 95.7, 60, and 77.3% for FNA alone, 50.8, 100, 100, 50.0, and 67.0% for BC alone, and 84.6, 100, 100, 76.2, and 89.7% for combining FNA with BC. In conclusion, both EUS‐guided FNA and BC are valuable modalities in the preoperative diagnosis of pancreatic ductal adenocarcinoma. When used in combination, the two modalities complement each other and achieve better diagnostic yield in pancreatic ductal adenocarcinoma than either FNA or BC alone. Diagn. Cytopathol. 2009. © 2009 Wiley‐Liss, Inc.
Primary angiosarcoma of the thyroid gland with recurrence diagnosed by fine needle aspiration: A case report
Authors: Isa Nurismah Md. , James Daniel T. , Saw Teong H. , Pennisi Robert , Gough Ian
Published: March 2009

Angiosarcoma of the thyroid is a rare and aggressive primary malignant tumor of the thyroid originally reported in patients from the Swiss Alpine region. Diagnosis of this tumor rests mainly on characteristic histopathological features of a malignant vascular tumor supported by immunopositivity for vascular markers e.g., CD31, Factor VIII, and CD34. Its cytological features, however, are not well‐defined. We describe a case of primary angiosarcoma of the thyroid in a 48‐year‐old female, who presented with a rapidly enlarging neck mass associated with compressive symptoms. She had a history of hypothyroidism. The initial fine needle aspiration cytology of the neck mass was negative. She then underwent left hemithyroidectomy. Histologically, the tumor showed poorly differentiated malignant cells with eccentrically‐placed nuclei, prominent nucleoli, and intracytoplasmic vacuoles admixed with mixed inflammatory cells. These showed immunopositivity for CD31 but were negative for CD34, Factor VIII, CK5/6, EMA, TTF‐1, Thyroglobulin, Calcitonin, Melan A, and Calretinin. A diagnosis of poorly differentiated malignant tumor consistent with angiosarcoma was made. The patient was treated with radiation therapy but developed recurrence of the tumor. Second aspiration cytology of the recurrent tumor yielded hypocellular smears containing singularly dispersed atypical cells having eccentrically‐placed nuclei with prominent macronucleoli and intracytoplasmic vacuoles within a background of inflammatory cells, consistent with recurrent angiosarcoma. Chemotherapy was started but she succumbed to the disease 7 months after diagnosis. The cytological, histopathological, immunohistochemical findings, and the clinical course are discussed. Diagn. Cytopathol. 2009. © 2009 Wiley‐Liss, Inc.
A technoeconomic and environmental life cycle comparison of green diesel to biodiesel and syndiesel
Authors: Kalnes Tom N. , Koers Ken P. , Marker Terry , Shonnard David R.
Published: March 2009

Green diesel, a renewable diesel fuel produced via the UOP/Eni Ecofining™ process, has the same fuel quality attributes as syndiesel but, over its life cycle, consumes less fossil fuel and generates less greenhouse gas emissions than petroleum diesel. From an investment standpoint, the production of green diesel is competitive with biodiesel. Moderately sized units consistent with current large‐scale biodiesel production can be economical, especially when integrated into an existing petroleum refinery. © 2009 American Institute of Chemical Engineers Environ Prog, 2009.
A compact finite difference method for solving Burgers' equation
Authors: Xie Shusen , Li Guangxing , Yi Sucheol , Heo Sunyeong
Published: March 2009

In this paper, a high‐order accurate compact finite difference method using the Hopf–Cole transformation is introduced for solving one‐dimensional Burgers' equation numerically. The stability and convergence analyses for the proposed method are given, and this method is shown to be unconditionally stable. To demonstrate efficiency, numerical results obtained by the proposed scheme are compared with the exact solutions and the results obtained by some other methods. The proposed method is second‐ and fourth‐order accurate in time and space, respectively. Copyright © 2009 John Wiley & Sons, Ltd.
Neuregulin‐1β and neuregulin‐1α differentially affect the migration and invasion of malignant peripheral nerve sheath tumor cells
Authors: Eckert Jenell M. , Byer Stephanie J. , Clodfelder‐Miller Buffie J. , Carroll Steven L.
Published: March 2009

Malignant peripheral nerve sheath tumors (MPNSTs) are the most common malignancy associated with neurofibromatosis Type 1 (NF1). These Schwann cell lineage‐derived sarcomas aggressively invade adjacent nerve and soft tissue, frequently precluding surgical resection. Little is known regarding the mechanisms underlying this invasive behavior. We have shown that MPNSTs express neuregulin‐1 (NRG‐1) β isoforms, which promote Schwann cell migration during development, and NRG‐1α isoforms, whose effects on Schwann cells are poorly understood. Hypothesizing that NRG‐1β and/or NRG‐1α promote MPNST invasion, we found that NRG‐1β promoted MPNST migration in a substrate‐specific manner, markedly enhancing migration on laminin but not on collagen type I or fibronectin. The NRG‐1 receptors erbB3 and erbB4 were present in MPNST invadopodia (processes mediating invasion), partially colocalized with focal adhesion kinase and the laminin receptor β1‐integrin and coimmunoprecipitated with β1‐integrin. NRG‐1β stimulated human and murine MPNST cell migration and invasion in a concentration‐dependent manner in three‐dimensional migration assays, acting as a chemotactic factor. Both baseline and NRG‐1β‐induced migration were erbB‐dependent and required the action of MEK 1/2, SAPK/JNK, PI‐3 kinase, Src family kinases and ROCK‐I/II. In contrast, NRG‐1α had no effect on the migration and invasion of some MPNST lines and inhibited the migration of others. While NRG‐1β potently and persistently activated Erk 1/2, SAPK/JNK, Akt and Src family kinases, NRG‐1α did not activate Akt and activated these other kinases with kinetics distinct from those evident in NRG‐1β‐stimulated cells. These findings suggest that NRG‐1β enhances MPNST migration and that NRG‐1β and NRG‐1α differentially modulate this process. © 2009 Wiley‐Liss, Inc.
Mitogen‐activated protein kinase‐signaling regulates the ability of Müller glia to proliferate and protect retinal neurons against excitotoxicity
Authors: Fischer Andy J. , Scott Melissa A. , Ritchey Eric R. , Sherwood Patrick
Published: March 2009

The purpose of this study was to investigate whether insulin, fibroblast growth factor (FGF), and mitogen‐activated protein kinase (MAPK) pathways protect retinal neurons against excitotoxicity and regulate the proliferation of Müller glia. We found that intraocular injections of insulin or FGF2 had variable effects upon the phosphorylation of ERK1/2, p38 MAPK, and CREB, and the expression of immediate early genes, cFos and Egr1. Accumulations of pERK1/2, p38 MAPK, pCREB, cFos and Egr1 in response to insulin or FGF2 were confined to Müller glia, whereas retinal neurons did not seem to respond to growth factors. Unlike FGF2, insulin stimulated microglia‐like cells to upregulate the intermediate filament transitin and lysosomal membrane glycoprotein (LMG). With microglia‐like cells and Müller glia stimulated by insulin or FGF2 there were profound effects upon numbers of dying neurons in response to excitotoxic damage. Although FGF2 significantly reduced numbers of dying neurons, insulin significantly increased numbers of dying neurons. In addition to neuroprotective affects, FGF2 also “primed” the Müller glia to proliferate following retinal damage, whereas insulin had no effect upon glial proliferation. Further, we found that FGF receptor isoform 1 (FGFR1) and FGFR3 were prominently expressed in the retina, whereas the insulin receptor and FGFR2 are not expressed, or are expressed at very low levels. We conclude that MAPK‐signaling through FGF receptors stimulates Müller glia to become more neuroprotective and progenitor‐like, whereas insulin acting on Müller and microglia‐like cells through unidentified receptors had the opposite effect. © 2009 Wiley‐Liss, Inc.
Shyness as a continuous dimension and emergent literacy in young children: is there a relation?
Authors: Spere Katherine , Evans Mary Ann
Published: March 2009

The present study assessed 89 children in a short‐term longitudinal study from Junior Kindergarten (age 4–5 years) through Grade 1 (age 6–7 years) using a variety of tests of emergent literacy. Children were assessed for reading skill (a composite of word recognition, decoding, and letter‐sound knowledge), phonological awareness, and oral language (i.e. both receptive and expressive vocabulary as well as syntax and fluency). Shyness was treated as a continuous variable rather than contrasting extreme groups of shy and non‐shy children. Shyness was modestly related to vocabulary, verbal fluency, and phonological awareness. Results suggest that among young children the association of greater shyness with compromised skill development potentially extends beyond the vocabulary domain to include emergent literacy more broadly. Copyright © 2009 John Wiley & Sons, Ltd.
Shyness, vocabulary and children's reticence in Saudi Arabian preschools
Authors: Crozier W. Ray , Badawood Asma
Published: March 2009

The aims of the present study are to examine whether preschool children's scores on a standardized test of vocabulary mediate or moderate the relation between shyness and reticence and to test whether any influence of vocabulary would be found for both teacher and parent assessments of shyness. Participants were 108 children (50 males), mean age, 63.96 months, attending preschool in Saudi Arabia. Teachers selected shy and non‐shy children and both teachers and parents rated the children on a shyness checklist. Children completed a test of receptive vocabulary. Systematic observations of verbal behaviour were made in ‘show and tell’ and play sessions. Shyness scores were negatively correlated with vocabulary test scores. Shy children were more reticent during ‘show and tell’ and play. Vocabulary test scores did not moderate relations between teacher‐assessed or parent‐assessed shyness and reticence. Vocabulary test scores did not mediate the relation between teacher‐assessed shyness and reticence but there was partial mediation in analyses involving parents' assessments. The variation in findings between different informants is discussed. Copyright © 2009 John Wiley & Sons, Ltd.
Differential role of β‐catenin in VEGF and histamine‐induced MMP‐2 production in microvascular endothelial cells
Authors: Doyle Jennifer L. , Haas Tara L.
Published: March 2009

Increases in endothelial cell permeability and production of matrix‐degrading enzymes are two early steps in the angiogenic process. Factors such as vascular endothelial growth factor (VEGF) and histamine induce the angiogenic process through alterations in both permeability and proteolysis. We hypothesized that β‐catenin acts as a positive regulator of MMP‐2 and MT1‐MMP transcription following VEGF or histamine stimulation. Rat microvascular endothelial cells were exposed to VEGF or histamine overnight and MMP‐2 protein production was assessed by gelatin zymography. Latent MMP‐2 protein levels were increased following VEGF and histamine treatment as were MMP‐2 mRNA transcript levels. Endothelial cells exposed to VEGF and histamine had an increased level of nuclear β‐catenin, which was sensitive to inhibition of the PI3‐kinase signaling pathway. Promoter assays indicated increased transcriptional activity of both MMP‐2 and MT1‐MMP in endothelial cells co‐transfected with luciferase reporter constructs and β‐catenin. Inhibition of β‐catenin signaling with inhibitor of catenin and T cell factor (ICAT) revealed that the VEGF‐induced increase in MMP‐2 mRNA is β‐catenin dependent. Interestingly, while MMP‐2 mRNA levels increased in response to histamine H1 or H2 receptor activation, significantly larger increases were observed in cells co‐treated with ICAT and histamine or the histamine receptor agonists, HTMT and dimaprit. While both VEGF and histamine increase nuclear β‐catenin and MMP‐2 production, the role of β‐catenin in MMP‐2 regulation differs between the two stimuli. J. Cell. Biochem. 107: 272–283, 2009. © 2009 Wiley‐Liss, Inc.
Combined preoxidation by permanganate and chlorine in enhancing the treatment of surface water
Authors: Liang Heng , Tian Jia Y , He Wen J , Han Hong D , Chen Zhong L , Li Gui B
Published: March 2009

BACKGROUND: Combined use of permanganate and chlorine has been shown to have synergistic action in disinfection. However, according to the literature the effects of combined preoxidation on coagulation and filtration have not been thoroughly investigated.

RESULTS: Laboratory and pilot experiments were conducted to evaluate the effect of the combined preoxidation by permanganate and chlorine on the treatment of River Luan water. Based on the reduction of the residual turbidity and UV254 after sedimentation and filtration, the optimum dosages of permanganate and chlorine were selected. The improvement of treated water quality was also achieved in the pilot processes. Permanganate reduced the amount of chlorine, while it enhanced chlorination and reduced trihalomethane production. The enhanced treatment efficiency could be explained by the synergistic effect of the preoxidants themselves and the effect of chlorine and intermediates such as hydrous manganese dioxide, which was formed in situ by permanganate reduction.

CONCLUSION: Laboratory and pilot studies demonstrated that combined preoxidation by permanganate and chlorine could enhance water treatment. Copyright © 2009 Society of Chemical Industry
Synthesis of new 1,3‐thiazepine derivatives
Authors: Struga Marta , Kossakowski Jerzy , Miroslaw Barbara. , Koziol Anna E. , Zimniak Andrzej
Published: March 2009

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Condensation of thiourea derivatives with 1,4‐dibromobutane gave 1,3‐thiazepine derivatives (1a,1b,1c−3a,3b,3c). Elementary analysis, MS and1H NMR spectra confirmed the identity of the products. The molecular structure of2bwas determined by an X‐ray analysis. J. Heterocyclic Chem., (2009).
Ultrasound‐accelerated synthesis of some bis‐compounds and their biological evaluation
Authors: Dabholkar Vijay V. , Ansari Faisal Y.
Published: March 2009

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A new series of bis‐1,5‐[2′H,3′H‐dihydro‐4′(substituted phenyl)‐1′,5′‐benzothiazipin‐2′‐oxy]‐3,3‐dimethyl‐1,4‐cyclohexadiene 3 and bis‐1,5‐[‐2′,3′,4′,5′‐teterahydro‐2′‐(substitutedphenyl)‐4′‐oxothiophen‐3′‐carboxylate]‐3,3‐dimethyl‐1,4‐cyclohexadiene 4 have been synthesized by reacting 1,3‐bis‐[substituted cinnamate]‐3,3‐dimethyl‐1,4‐cyclohexadiene 2 with 2‐aminothiophenol and thiogylcolic acid, respectively, through an environmentally benign procedure. The title compounds have been evaluated for their antimicrobial activities. Reaction under ultrasound irradiation resulted in enhancement of yields and reaction rates. Structures of the synthesized compounds have been elucidated on the basis of the elemental analysis and spectral data. J. Heterocyclic Chem., (2009).
Adrenal hemangioma‐adenoma: An exceedingly rare adrenal collision tumor
Authors: Siddiqi Aheed J. , Miller Frank H. , Kasuganti Deepa , Nikolaidis Paul
Published: March 2009

Adrenal collision tumors are rare clinical entities referring to separate coexisting adjacent tumors involving an adrenal gland with sharp demarcation between the two and without a substantial histologic admixture at the interface. We report a case of a 60‐year‐old female patient with an exceedingly rare adrenal hemangioma‐adenoma collision tumor. To our knowledge, this is the first report of a collision tumor comprising an adrenal hemangioma and an adenoma. J. Magn. Reson. Imaging 2009;29:949–952. © 2009 Wiley‐Liss, Inc.
Globus pallidus magnetization transfer ratio, T1 and T2 in primary biliary cirrhosis: Relationship with disease stage and age
Authors: Hollingsworth Kieren G. , Jones David E. , Aribisala Benjamin S. , Thelwall Peter E. , Taylor Roy , Newton Julia L. , Blamire Andrew M.
Published: March 2009

Purpose

To determine whether the magnetization transfer ratio (MTR) of the globus pallidus (GP) in patients with primary biliary cirrhosis (PBC) correlates with age, disease stage, and fatigue, using T1 and T2 mapping to determine whether the mechanism of change is consistent with manganese deposition in the GP as suggested by previous reports.

Materials and Methods

In all, 30 early‐stage PBC patients, four end‐stage PBC patients, and 14 female controls were recruited to age‐matched groups. MTR, T1 and T2 measurements were performed. A bilateral region of interest (ROI)‐based analysis was used to calculate GP MTR, T1, and T2 values. These were correlated with age, disease status, and fatigue.

Results

MTR measurements showed a significant, negative correlation with age for controls and early‐stage PBC patients, a positive correlation with T2, and no correlation with T1. Only GP T2 is significantly lower in early‐stage PBC patients than controls, while end‐stage patients demonstrated a simultaneous reduction in T1 and MTR, consistent with GP manganese deposition.

Conclusion

MTR measurements correlate with age in both early‐stage patient and control groups, but are not associated with manganese deposition or fatigue severity: only the end‐stage disease group shows changes in MTR, T1, T2 that are consistent with manganese deposition. J. Magn. Reson. Imaging 2009;29:780–784. © 2009 Wiley‐Liss, Inc.
Sodium mapping in focal cerebral ischemia in the rat by quantitative 23Na MRI
Authors: Yushmanov Victor E. , Yanovski Boris , Kharlamov Alexander , LaVerde George , Boada Fernando E. , Jones Stephen C.
Published: March 2009

Purpose

To validate 23Na twisted projection magnetic resonance imaging (MRI) as a quantitative technique to assess local brain sodium concentration ([Na+]br) during rat focal ischemia every 5.3 minutes.

Materials and Methods

The MRI protocol included an ultrashort echo‐time (0.4 msec), a correction of radiofrequency (RF) inhomogeneities by B1 mapping, and the use of 0–154 mM NaCl calibration standards. To compare MRI [Na+]br values with those obtained by emission flame photometry in precision‐punched brain samples of about 0.5 mm3 size, MR images were aligned with a histological three‐dimensional reconstruction of the punched brain and regions of interest (ROIs) were placed precisely over the punch voids.

Results

The Bland–Altman analysis of [Na+]br in normal and ischemic cortex and caudate putamen of seven rats quantitated by 23Na MRI and flame photometry yielded a mean bias and limits of agreement (at ±1.96 SD) of 2% and 43% of average, respectively. A linear increase in [Na+]br was observed between 1 and 6 hours after middle cerebral artery occlusion.

Conclusion

23Na MRI provides accurate and reliable results within the whole range of [Na+]br in ischemia with a temporal resolution of 5.3 minutes and precisely targeted submicroliter ROIs in selected brain structures. J. Magn. Reson. Imaging 2009;29:962–966. © 2009 Wiley‐Liss, Inc.
Clinical correlations of brain lesion distribution in multiple sclerosis
Authors: Vellinga M.M. , Geurts J.J.G. , Rostrup E. , Uitdehaag B.M.J. , Polman C.H. , Barkhof F. , Vrenken H.
Published: March 2009

Purpose

To explore relations between spatial distribution of multiple sclerosis (MS) lesions, and disability. In MS, the presence of asymptomatic brain lesions challenges the prediction of disability based on conventional brain MRI. Hypothesizing that symptomatology may partly be determined by lesion location, this retrospective study explored relations between lesion location and disability using voxelwise analyses in standard space.

Materials and Methods

Using nonparametric permutation‐based statistics, voxelwise lesion probability on T2 lesion masks was related to expanded disability status scale (EDSS) and MS functional composite (MSFC) subdomain scores and demographic characteristics of 325 MS patients. To identify statistically significant locations, a cluster‐forming threshold of 3.1 was used.

Results

In clusters in the periventricular region, lesion probability correlated significantly (P < 0.001) with disability and disease duration, and was higher in progressive than in relapsing disease. When controlled for lesion load (LL), no significant clusters survived. Presence and number of spinal cord lesions did not correlate with lesion probability in any location, and did not influence correlations with disability when included in its analyses.

Conclusion

Periventricular lesions were related to disability. LL influenced relations between disability and lesion probability throughout the brain, suggesting interplay between lesional burden and its location in determining disability in MS. J. Magn. Reson. Imaging 2009;29:768–773. © 2009 Wiley‐Liss, Inc.
Removing background phase variations in susceptibility‐weighted imaging using a fast, forward‐field calculation
Authors: Neelavalli Jaladhar , Cheng Yu‐Chung N. , Jiang Jing , Haacke E. Mark
Published: March 2009

Purpose

To estimate magnetic field variations induced from air–tissue interface geometry and remove their effects from susceptibility‐weighted imaging (SWI) data.

Materials and Methods

A Fourier transform–based field estimation method is used to calculate the field deviation arising from air–tissue interface geometry. This is accomplished by manually drawing or automatically detecting the sinuses, the mastoid cavity, and the head geometry. The difference in susceptibility, Δχ, between brain tissue and air spaces is then calculated using a residual‐phase minimization approach. SWI data are corrected by subtracting the predicted phase from the original phase images. Resultant phase images are then used to perform the SWI postprocessing.

Results

Significant improvement in the postprocessed SWI data is demonstrated, most notably in the frontal and midbrain regions and to a lesser extent at the boundary of the brain. Specifically, there is much less dropout of signal after phase correction near air–tissue interfaces, making it possible to see vessels and structures that were often incorrectly removed by the conventional SWI postprocessing.

Conclusion

The Fourier transform–based field estimation method is a powerful 3D background phase removal method for improving SWI images, providing clearer images of the forebrain and the midbrain regions. J. Magn. Reson. Imaging 2009;29:937–948. © 2009 Wiley‐Liss, Inc.
Comparison of dynamic MRI at 3.0T and MDCT of pancreatobiliary disease: Evaluation with source, MPR, CPR, and MIP images for image quality and hepatic arterial and portal venous vessel conspicuity
Authors: Uchida Masafumi , Sakoda Jun , Arikawa Shunji , Kunou Yukiko , Ishibashi Masatoshi , Abe Toshi , Hayabuchi Naofumi
Published: March 2009

Purpose

To compare contrast material‐enhanced three‐dimensional (3D) magnetic resonance imaging (MRI) at 3.0T and multidetector row computed tomography (MDCT) in the same patient with regard to image quality of pancreatobiliary disease and hepatic vascular conspicuity.

Materials and Methods

This study enrolled 32 patients with pancreatobiliary disease who underwent both gadolinium‐enhanced 3D dynamic MRI and multiphasic CT using 16‐MDCT. Data analysis of image quality was performed by two radiologists based on source images, multiplanar reconstruction (MPR), curved planar reconstruction (CPR), and maximum intensity projection (MIP) reconstruction. Determination of image quality was based on a 4‐point image quality rating scale.

Results

The overall image quality of the MRI axial images was superior to that of the axial MDCT images. The MRI protocol yielded an average score of 3.8 points versus 3.5 for the CT imaging. No significant difference was found between 3.0T MRI and MDCT images in MPR or CPR image quality. Image quality for visualization of the distal intrahepatic segmental arteries was significantly improved using MDCT imaging. No significant difference was found between the MDCT and 3.0T MR in portal vein branch image quality.

Conclusion

High‐resolution dynamic contrast‐enhanced MR imaging at 3.0T is a comprehensive technique which provides high image quality in pancreatobiliary disease. J. Magn. Reson. Imaging 2009;29:846–852. © 2009 Wiley‐Liss, Inc.
Accelerated phase‐contrast MR imaging: Comparison of k‐t BLAST with SENSE and doppler ultrasound for velocity and flow measurements in the aorta
Authors: Stadlbauer Andreas , van der Riet Wilma , Globits Sebastian , Crelier Gerard , Salomonowitz Erich
Published: March 2009

Purpose

To evaluate differences in velocity and flow measurements in the aorta between accelerated phase‐contrast (PC) magnetic resonance imaging (MRI) using SENSE and k‐t BLAST and in peak velocity to Doppler ultrasound.

Materials and Methods

Two‐dimensional PC‐MRI perpendicular to the ascending and descending aorta was performed in 11 volunteers using SENSE (R = 2) and k‐t BLAST (2‐, 4‐, 6‐, and 8‐fold). Peak velocity, mean velocity, and stroke volume of the accelerated PC‐MRI experiments were correlated. Peak velocities were compared to Doppler ultrasound.

Results

All acceleration techniques showed significant correlations for peak velocity with Doppler ultrasound. However, k‐t BLAST 6 and 8 showed a significant underestimation. Strong correlations between SENSE and k‐t BLAST were found for all three parameters. Significant differences in peak velocity were found between SENSE and all k‐t BLAST experiments, but not for 2‐fold k‐t BLAST in the ascending aorta, and 2‐ and 4‐fold k‐t BLAST in the descending aorta. For mean velocity no significant differences were found. Stroke volume showed significant differences for all k‐t BLAST experiments in the ascending and for 6‐ and 8‐fold k‐t BLAST in the descending aorta.

Conclusion

Peak velocity of accelerated PC‐MRI correlated with CW Doppler measurements, but high k‐t BLAST acceleration factors lead to a significant underestimation. SENSE with R = 2 and 2‐fold k‐t BLAST are most highly correlated in phase‐contrast flow measurements. J. Magn. Reson. Imaging 2009;29:817–824. © 2009 Wiley‐Liss, Inc.
Assessment of iron distribution between liver, spleen, pancreas, bone marrow, and myocardium by means of R2 relaxometry with MRI in patients with β‐thalassemia major
Authors: Papakonstantinou Olympia , Alexopoulou Efthymia , Economopoulos Nikos , Benekos Odysseas , Kattamis Antonis , Kostaridou Stavroula , Ladis Vasilis , Efstathopoulos Efstathios , Gouliamos Athanassios , Kelekis Nikolaos L.
Published: March 2009

Purpose

To investigate the correlation between the degree of hepatic, splenic, pancreatic, vertebral bone marrow (VBM), and myocardial siderosis, as expressed by relaxation rate (R2 = 1/T2) values, in patients with thalassemia.

Materials and Methods

R2 relaxation rate values of liver, spleen, VBM, pancreas, and myocardium were estimated in 68 consecutive transfusion‐dependent patients with β‐thalassemia major and 10 healthy controls using a respiratory triggered 16‐echo Carr‐Purcell‐Meiboom‐Gill (CPMG) spin echo sequence.

Results

Hepatic R2 values were significantly increased in all 68 patients; VBM, pancreatic, and myocardial R2 values were increased in 67/68, 35/47, and 47/61 patients, whereas five patients showed decreased pancreatic R2 attributed to fatty degeneration. Of the 39 nonsplenectomized patients, splenic R2 values were decreased in 30 and normal in nine patients. Hepatic R2 values correlated with splenic (r = 0.63, P < 0.001), VBM (r = 0.52, P < 0.001), but not with myocardial and pancreatic R2 values.

Conclusion

Despite positive correlations between the degree of hepatic, splenic, and VBM siderosis, as expressed by respective R2 values, there was variability of iron distribution patterns in thalassemic patients. Unpredictable patterns of iron distribution may be seen, such as normal signal of the spleen in the presence of siderotic liver, resembling primary hemochromatosis. Fatty degeneration of the pancreas was not uncommon. J. Magn. Reson. Imaging 2009;29:853–859. © 2009 Wiley‐Liss, Inc.
Magnetic resonance imaging and three‐dimensional ultrasound of carotid atherosclerosis: Mapping regional differences
Authors: Krasinski Adam , Chiu Bernard , Fenster Aaron , Parraga Grace
Published: March 2009

Purpose

To evaluate differences in carotid atherosclerosis measured using magnetic resonance imaging (MRI) and three‐dimensional ultrasound (3DUS).

Materials and Methods

Ten subject volunteers underwent carotid 3DUS and MRI (multislice black blood fast spin echo, T1‐weighted contrast, double inversion recovery, 0.5 mm in‐plane resolution, 2 mm slice, 3.0 T) within 1 hour. 3DUS and MR images were manually segmented by two observers providing vessel wall and lumen contours for quantification of vessel wall volume (VWV) and generation of carotid thickness maps.

Results

MRI VWV (1040 ± 210 mm3) and 3DUS VWV (540 ± 110 mm3) were significantly different (P < 0.0001). When normalized for the estimated adventitia volume, mean MRI VWV decreased 240 ± 50 mm3 and was significantly different from 3DUS VWV (P < 0.001). Two‐dimensional carotid maps showed qualitative evidence of regional differences in the plaque and vessel wall thickness between MR and 3DUS in all subjects. Power Doppler US confirmed that heterogeneity in the common carotid artery in all patients resulted from apparent flow disturbances, not atherosclerotic plaque.

Conclusion

MRI and 3DUS VWV were significantly different and carotid maps showed homogeneous thickness differences and heterogeneity in specific regions of interest identified as MR flow artifacts in the common carotid artery. J. Magn. Reson. Imaging 2009;29:901–908. © 2009 Wiley‐Liss, Inc.
fMRI activation mapping as a percentage of local excitation: Consistent presurgical motor maps without threshold adjustment
Authors: Voyvodic James T. , Petrella Jeffrey R. , Friedman Allan H.
Published: March 2009

Purpose

To evaluate the performance of a relative activation amplitude algorithm, versus standard t‐value thresholding, for reliably establishing the location, amplitude, and spatial extent of functional magnetic resonance imaging (fMRI) brain activation for presurgical planning.

Materials and Methods

Diagnostic fMRI maps from 42 neurosurgical patients performing a simple hand movement task were analyzed. Relative activation maps were made by normalizing statistical t‐value maps to the local peak activation amplitude within each functional brain region. The spatial distribution of activation was quantified and compared across mapping algorithms, subjects, and scan duration.

Results

Whereas the spatial distribution of blood oxygenation level‐dependent (BOLD) t‐value statistical activation maps was highly variable across subjects and scan duration, the spatial distribution of relative activation maps was highly reproducible both within individual subjects and across different subjects. In every case the 40% most active voxels in the cortical hand region were consistently localized to the pre‐ and postcentral gyri of the sensorimotor cortex.

Conclusion

The reproducibility and anatomical specificity of the spatiotemporal pattern of BOLD activation makes relative amplitude fMRI mapping a useful tool for clinical imaging, where accuracy, reproducibility, and quality control are critical concerns. J. Magn. Reson. Imaging 2009;29:751–759. © 2009 Wiley‐Liss, Inc.
Free‐breathing diffusion‐weighted imaging for the assessment of inflammatory activity in Crohn's disease
Authors: Kiryu Shigeru , Dodanuki Keiichi , Takao Hidemasa , Watanabe Makoto , Inoue Yusuke , Takazoe Masakazu , Sahara Rikisaburo , Unuma Kiyohito , Ohtomo Kuni
Published: March 2009

Purpose

To investigate the application of free‐breathing diffusion‐weighted MR imaging (DWI) to the assessment of disease activity in Crohn's disease.

Materials and Methods

Thirty‐one patients with Crohn's disease were investigated using free‐breathing DWI without special patient preparation or IV or intraluminal contrast agent. The bowel was divided into seven segments, and disease activity was assessed visually on DWI. For quantitative analysis, the apparent diffusion coefficient (ADC) was measured in each segment. The findings of a conventional barium study or surgery were regarded as the gold standard for evaluating the diagnostic ability of DWI to assess disease activity.

Results

Upon visual assessment, the sensitivity, specificity, and accuracy for the detection of disease‐active segments were 86.0, 81.4, and 82.4%, respectively. In the quantitative assessment, the ADC value in the disease‐active area was lower than that in disease‐inactive area in small and large bowels (1.61 ± 0.44×10−3 mm2/s versus 2.56 ± 0.51 × 10−3 mm2/s in small bowel and 1.52 ± 0.43 × 10−3 mm2/s versus 2.31 ± 0.59 × 10−3 mm2/s in large bowel, respectively, P<0.001).

Conclusion

Free‐breathing DWI is useful in the assessment of Crohn's disease. The accuracy of DWI is high in evaluating disease activity, especially in the small bowel, and the ADC may facilitate quantitative analysis of disease activity. J. Magn. Reson. Imaging 2009;29:880–886. © 2009 Wiley‐Liss, Inc.
1H and hyperpolarized 3He MR imaging of mouse with LPS‐induced inflammation
Authors: Olsson Lars E. , Smailagic Amir , Önnervik Per‐Ola , Hockings Paul D.
Published: March 2009

Purpose

To evaluate the lipopolysaccharide (LPS) model of chronic obstructive pulmonary disease (COPD) in mouse with 1H and hyperpolarized (HP) 3He MR imaging.

Materials and Methods

Axial slices of the lung volume were acquired with HP 3He and 1H MRI at 4, 24, and 48 h after LPS exposure. A quantitative ventilation index was calculated from two HP 3He acquisitions. A bronchoalveolar lavage (BAL) for a cell count was performed following magnetic resonance imaging (MRI).

Results

The LPS exposure resulted in a significant increase of cells in BAL, with maximum at 48 h. Lesions on 3He images were characterized by ventilation defects, whereas lesions on 1H images were hyperintense and were attributed to edema. The number of lesions was at maximum at 48 h. At this time point, and for both 3He and 1H MRI, the volume of the lesions was significantly higher for LPS‐exposed mice compared to controls. At 4, 24, and 48 h the ventilation index from the 3He data was significantly smaller for the LPS‐exposed animals compared to controls.

Conclusion

The time point 48 h after LPS exposure was advantageous for MRI evaluation. Functional read‐out with 3He MRI seems to be more sensitive than conventional 1H MRI. J. Magn. Reson. Imaging 2009;29:977–981. © 2009 Wiley‐Liss, Inc.
NMR properties of human median nerve at 3 T: Proton density, T1, T2, and magnetization transfer
Authors: Gambarota Giulio , Mekle Ralf , Mlynárik Vladimír , Krueger Gunnar
Published: March 2009

Purpose

To measure the proton density (PD), the T1 and T2 relaxation time, and magnetization transfer (MT) effects in human median nerve at 3 T and to compare them with the corresponding values in muscle.

Materials and Methods

Measurements of the T1 and T2 relaxation time were performed with an inversion recovery and a Carr‐Purcell‐Meiboom‐Gill (CPMG) imaging sequence, respectively. The MT ratio was measured by acquiring two sets of 3D spoiled gradient‐echo images, with and without a Gaussian saturation pulse.

Results

The median nerve T1 was 1410 ± 70 msec. The T2 decay consisted of two components, with average T2 values of 26 ± 2 msec and 96 ± 3 msec and normalized amplitudes of 78 ± 4% and 22 ± 4%, respectively. The dominant component is likely to reflect myelin water and connective tissue, and the less abundant component originates possibly from intra‐axonal water protons. The value of proton density of MRI‐visible protons in median nerve was 81 ± 3% that of muscle. The MT ratio in median nerve (40.3 ± 2.0%) was smaller than in muscle (45.4 ± 0.5%).

Conclusion

MRI‐relevant properties, such as PD, T1 and T2 relaxation time, and MT ratio were measured in human median nerve at 3 T and were in many respects similar to those of muscle. J. Magn. Reson. Imaging 2009;29:982–986. © 2009 Wiley‐Liss, Inc.
Change leadership: case study of a global energy company
Authors: Higgs Malcolm , Rowland Deborah
Published: March 2009

Organizations operating on a global basis have wrestled with the dilemma of achieving a balance between global standardization and local differentiation. Similar dilemmas arise from a review of the literature around the challenges of implementing change successfully. There is, however, agreement that leaders play a significant role in resolving these dilemmas in the process of implementing strategic change within global organizations.

This paper explores the literature on global organizations and change leadership. Building from this review, the paper presents the findings from a case study which explores the implementation of a global strategy within a large energy corporation.

Based on a review of nine interviews, internal communication documents, and employee attitude survey data we found that change approaches which recognize the complexity of change combined with an involving and engaging leadership style tend to result in successful change implementation. In addition, the balancing of the global/local dilemma by leaders contributed notably to change success.

We conclude with suggestions for further research and a brief discussion of the implications of the findings for the development of leaders capable of working effectively in a global organization.

Copyright © 2009 John Wiley & Sons, Ltd.
HILIC separation and quantitation of water‐soluble vitamins using diol column
Authors: Karatapanis Andreas E. , Fiamegos Yiannis C. , Stalikas Constantine D.
Published: March 2009

Hydrophilic interaction liquid‐chromatography (HILIC) in conjunction with diode array detection has been applied for the separation of selected‐water‐soluble vitamins using an end‐capped HILIC‐diol column. Vitamins with significant biological importance, such as thiamine (B1), riboflavin (B2), nicotinic acid (B3), nicotinamide (B3), pyridoxine (B6), folic acid (B9), cyanocobalamin (B12) and ascorbic acid (vitamin C) were simultaneously separated. Chromatographic conditions including type and percentage of organic modifier in the mobile phase, pH, type and concentration of buffer salt and flow rate were investigated. ACN was shown to offer superior separation for the compounds tested as compared to methanol, isopropanol and THF. Isocratic separation and analysis were achieved for six vitamins (B1, B2, nicotinic acid/nicotinamide, B6 and C) at ACN–H2O 90:10, containing ammonium acetate 10 mM, triethylamine 20 mM, pH 5.0, using a flow rate of 0.8 mL/min, while a gradient was necessary to resolve a mixture of all eight water‐soluble vitamins. The HILIC method was validated and successfully applied to the analysis of a pharmaceutical formulation and an energy drink negating the need for time consuming clean‐up steps.
HPLC enantioseparation of β2‐homoamino acids using crown ether‐based chiral stationary phase
Authors: Berkecz Róbert , Ilisz István , Misicka Aleksandra , Tymecka Dagmara , Fülöp Ferenc , Choi Hee Jung , Hyun Myung Ho , Péter Antal
Published: March 2009

RP high‐performance liquid chromatographic methods were developed for the enantioseparation of eleven unusual β2‐homoamino acids. The underivatized analytes were separated on a chiral stationary phase containing (+)‐(18‐crown‐6)‐2,3,11,12‐tetracarboxylic acid as chiral selector. The effects of organic (alcoholic) and acidic modifiers, the mobile phase composition and temperature on the separation were investigated. The structures of the substituents in the α‐position of the analytes substantially influenced the retention and resolution. The elution sequence was determined in some cases: the S enantiomers eluted before the R enantiomers.
Peptide nucleic acid (PNA) binding and its effect on in vitro transcription in friedreich's ataxia triplet repeats
Authors: Belotserkovskii Boris P. , Liu Richard , Hanawalt Philip C.
Published: March 2009

Peptide nucleic acids (PNAs) are DNA mimics in which peptide‐like linkages are substituted for the phosphodiester backbone. Homopyrimidine PNAs can invade double‐stranded DNA containing the homologous sequence by displacing the homopyrimidine strand from the DNA duplex and forming a PNA/DNA/PNA triplex with the complementary homopurine strand. Among biologically interesting targets for triplex‐forming PNA are (GAA/CTT)n repeats. Expansion of these repeats results in partial inhibition of transcription in the frataxin gene, causing Friedreich's ataxia. We have studied PNA binding and its effect on T7 RNA polymerase transcription in vitro for short repeats (n = 3) and for long repeats (n = 39), placed in both possible orientations relative to the T7 promoter such that either the GAA‐strand, or the CTT‐strand serves as the template for transcription. In all cases PNA bound specifically and efficiently to its target sequence. For the short insert, PNA binding to the template strand caused partial transcription blockage with well‐defined sites of RNA product truncation in the region of the PNA‐binding sequence, whereas binding to the nontemplate strand did not block transcription. However, PNA binding to long repeats, whether in the template or the nontemplate strand, resulted in a dramatic reduction of the amount of full‐length transcription product, although in the case of the nontemplate strand there were no predominant truncation sites. Biological implications of these results are discussed. © 2009 Wiley‐Liss, Inc.