bluuebunny/crossref_metadata_2025_split huggingface dataset:
Quantitative diffusion imaging with steady‐state free precession
Authors: Deoni Sean C.L. , Peters Terry M. , Rutt Brian K. 
Published: January 2004

AbstractThe addition of a single, unbalanced diffusion gradient to the steady‐state free precession (SSFP) imaging sequence sensitizes the resulting signal to free diffusion. Unfortunately, the confounding influence of both longitudinal (T1) and transverse (T2) relaxation on the diffusion‐weighted SSFP (dwSSFP) signal has made it difficult to quantitatively determine the apparent diffusion coefficient (ADC). Here, a multistep method in which the T1, T2, and spin density (Mo) constants are first determined using a rapid mapping technique described previously is presented. Quantitative ADC can then be determined through a novel inversion of the appropriate signal model. The accuracy and precision of our proposed method (which we term DESPOD) was determined by comparing resulting ADC values from phantoms to those calculated from traditional diffusion‐weighted echo planar imaging (dwEPI) images. Error within the DESPOD‐derived ADC maps was found to be less than 3%, with good precision over a biologically relevant range of ADC values. Magn Reson Med 51:428–433, 2004. © 2004 Wiley‐Liss, Inc.
FAIR true‐FISP perfusion imaging of the kidneys
Authors: Martirosian Petros , Klose Uwe , Mader Irina , Schick Fritz 
Published: January 2004

AbstractMost arterial spin labeling (ASL) techniques apply echoplanar imaging (EPI) because this strategy provides relatively high SNR in short measuring times. Unfortunately, those techniques are very susceptible to static magnetic field inhomogeneities and perfusion signals from organs with fast transverse relaxation might decrease due to the exchange of water molecules in capillaries and organ tissue combined with relatively long echo times of EPI sequences. To overcome these problems a novel imaging technique, FAIR True‐FISP, was developed. It combines a FAIR (flow‐sensitive alternating inversion recovery) perfusion preparation and a true fast imaging with steady precession (True‐FISP) data acquisition strategy. True‐FISP was chosen since this sequence type does not show the mentioned disadvantages of EPI, but provides a similar SNR per measuring time. An important problem of this approach is that True‐FISP sequences usually work in a steady state which is independent of a previous preparation of magnetization. For this reason a sequence structure had to be developed which keeps the advantages of True‐FISP and makes the signal intensity sensitive to the FAIR preparation. Breathhold and nonbreathhold examinations of kidneys are presented and possible strategies to quantitative flow measurements are reported. It is shown that correction of spatially inhomogeneous receiver coil characteristics is easily feasible and leads to clinically valuable perfusion examinations of kidneys without application of potentially nephrotoxic contrast media. Magn Reson Med 51:353–361, 2004. © 2004 Wiley‐Liss, Inc.
dGEMRIC (delayed gadolinium‐enhanced MRI of cartilage) indicates adaptive capacity of human knee cartilage
Authors: Tiderius Carl Johan , Svensson Jonas , Leander Peter , Ola Thorsson , Dahlberg Leif 
Published: January 2004

AbstractDelayed gadolinium‐enhanced MRI of cartilage (dGEMRIC) is a new imaging technique to estimate joint cartilage glycosaminoglycan content byT1‐relaxation time measurements after penetration of the hydrophilic contrast agent Gd‐DTPA2‐. This study compares dGEMRIC in age‐matched healthy volunteers with different levels of physical activity: Group 1 (n = 12): nonexercising individuals; Group 2 (n = 16): individuals with physical exercise averaging twice weekly; Group 3 (n = 9): male elite runners. dGEMRIC was performed 2 hr after an intravenous injection of Gd‐DTPA2‐at 0.3 mmol/kg body weight.T1differed significantly between the three different levels of physical exercise.T1values (mean of medial and lateral femoral cartilage) for Groups 1, 2, and 3 were: 382 ± 33, 424 ± 22 and 476 ± 36, respectively (ms, mean ± SD) (P= 0.0004, 1 vs. 2 and 0.0002, 2 vs. 3). Irrespective of the exercise level,T1was longer in lateral compared to medial femoral cartilage (P= 0.00005; n = 37). In conclusion, this cross‐sectional study indicates that human knee cartilage adapts to exercise by increasing the glycosaminoglycan content. Furthermore, results suggest a compartmental difference within the knee with a higher glycosaminoglycan content in lateral compared to medial femoral cartilage. A higher proportion of extracellular water, i.e., larger distribution volume, may to some extent explain the highT1in the elite runners. Magn Reson Med 51:286–290, 2004. © 2004 Wiley‐Liss, Inc.
1H NMR detection of vitamin C in human brain in vivo
Authors: Terpstra Melissa , Gruetter Rolf 
Published: January 2004

AbstractVitamin C (ascorbate) is well established as an essential nutrient that functions as an antioxidant. Since it is present in the human brain at detectable concentrations, this study was designed to detect and quantify ascorbate in the human brain in vivo using 1H NMR spectroscopy (MRS). Ascorbate was consistently detected in all five study subjects, and was measured using MEGA‐PRESS difference editing. The in vivo resonance pattern was consistent with that of ascorbate based on position, line width, peak pattern, and relative intensity. Metabolites with a potential for coediting were assessed using phantom solutions. The putative resonances of myo‐inositol, lactate, glycerophosphocholine, phosphocholine, and phosphoethanolamine were detected at positions distinct from those of ascorbate. This study represents the first in vivo detection of vitamin C in the human brain using 1H MRS. A concentration of 1.3 ± 0.3 μmol/g (mean ± SD, N = 4) was estimated. Magn Reson Med 51:225–229, 2004. © 2004 Wiley‐Liss, Inc.
Distribution of intramyocellular lipids in human calf muscles as determined by MR spectroscopic imaging
Authors: Vermathen Peter , Kreis Roland , Boesch Chris 
Published: January 2004

AbstractIn this study the distribution of intramyocellular lipids (IMCL) in human calf muscles was determined by 1H‐MR spectroscopic imaging (MRSI) measurements. An obstacle for MRSI measurements in the calf, including different muscles, is the inevitable inclusion of regions with high concentrations of extramyocellular lipids (EMCL). This can lead to signal bleeding and consequently to unpredictable overlaps of IMCL resonances with EMCL in voxels of interest. The results of this study show that signal bleeding from EMCL can be substantially reduced in voxels from calf muscles by the application of a lipid extrapolation (LE) procedure (Haupt et al., Magn Reson Med 1996;35:678). The spectra of all voxels located within muscle tissue were fitted, and the metabolite values were assigned to one of 10 different muscles based on image segmentation. Significant IMCL differences between some muscles were obtained, with high values in m. soleus and two to three times lower values in the tibialis anterior, tibialis posterior, and gastrocnemius muscles. In addition to gross differences between muscles, significant intersubject differences were observed in both IMCL content and distribution over different muscles. A significant correlation between fiber orientation (obtained from orientation‐dependent dipolar coupling of creatine and taurine resonances) and IMCL content was found, indicating that IMCL content is directly correlated to biomechanical properties. Magn Reson Med 51:253–262, 2004. © 2004 Wiley‐Liss, Inc.
Quantification of multicontrast vascular MR images with NLSnake, an active contour model: In vitro validation and in vivo evaluation
Authors: Desbleds Mansard Catherine , Canet Soulas Emmanuelle P. , Anwander Alfred , Chaabane Linda , Neyran Bruno , Serfaty Jean‐Michel , Magnin Isabelle E. , Douek Philippe C. , Orkisz Maciej 
Published: January 2004

AbstractVessel‐wall measurements from multicontrast MRI provide information on plaque structure and evolution. This requires the extraction of numerous contours. In this work a contour‐extraction method is proposed that uses an active contour model (NLSnake) adapted for a wide range of MR vascular images. This new method employs length normalization for the purpose of deformation computation and offers the advantages of simplified parameter tuning, fast convergence, and minimal user interaction. The model can be initialized far from the boundaries of the region to be segmented, even by only one pixel. The accuracy and reproducibility of NLSnake endoluminal contours were assessed on vascular phantom MR angiography (MRA) and high‐resolution in vitro MR images of rabbit aorta. An in vivo evaluation was performed on rabbit and clinical data for both internal and external vessel‐wall contours. In phantoms with 95% stenoses, NLSnake measured 94.3% ± 3.8%, and the accuracy was even better for milder stenoses. In the images of rabbit aorta, variability between NLSnake and experts was less than interobserver variability, while the maximum intravariability of NLSnake was equal to 1.25%. In conclusion, the NLSnake technique successfully quantified the vessel lumen in multicontrast MR images using constant parameters. Magn Reson Med 51:370–379, 2004. © 2004 Wiley‐Liss, Inc.
MRI detection of early endothelial activation in brain inflammation
Authors: Sibson Nicola R. , Blamire Andrew M. , Bernades‐Silva Martine , Laurent Sophie , Boutry Sébastien , Muller Robert N. , Styles Peter , Anthony Daniel C. 
Published: January 2004

AbstractMRI is an increasingly important clinical tool, but it is clear that conventional imaging fails to identify the full extent of lesion load in certain conditions, such as multiple sclerosis. The aim of this study was to determine whether a novel contrast agent (Gd‐DTPA‐B(sLeX)A, which contains an sLeX mimetic moiety that enables it to bind to the adhesion molecule E‐selectin) can be used to identify endothelial activation in the brain. Microinjection of the proinflammatory cytokines IL‐1β or TNF‐α into the striatum of Wistar rats rapidly induces focal adhesion molecule expression on the endothelium in the absence of MRI‐visible changes. This phenomenon was used to investigate the potential of Gd‐DTPA‐B(sLeX)A to reveal MRI‐invisible brain pathology. T1‐weighted serial images were acquired in anesthetized animals before and after administration of Gd‐DTPA‐B(sLeX)A, 3–4 hr after cytokine was injected intracerebrally. Both TNF‐α and IL‐1β up‐regulated E‐selectin on the brain endothelium, which correlated with increased signal intensity observed after administration of the novel contrast agent. No enhancement was visible with the nonselective contrast agent Gd‐DTPA‐BMA, indicating that there was no leakage of the agent across the blood–brain barrier (BBB) or nonselective binding to the endothelium. These data demonstrate the potential of such contrast agents for the early detection of brain injury and inflammation. Magn Reson Med 51:248–252, 2004. © 2004 Wiley‐Liss, Inc.
Serum troponin T levels and echocardiographic evaluation in children treated with doxorubicin
Authors: Kısmet Erol , Varan Ali , Ayabakan Canan , Alehan Dursun , Portakal Oytun , Büyükpamukçu Münevver 
Published: January 2004

AbstractObjectiveWe investigated the usefulness of serum cardiac Troponin T (cTnT) to detect doxorubicin related cardiotoxicity as a non‐invasive and reliable method.Patients and MethodsTwenty‐four patients who received doxorubicin for their solid tumors at cumulative doses of 400 mg/m2 or higher, between June 1982 and August 2000, were included in this study. None of them had clinical signs or symptoms of cardiotoxicity. The age range was 3–31 years (median 14), and male to female ratio was 14/10. The systolic and diastolic cardiac functions were evaluated by two‐dimensional, M‐mode, and Doppler echocardiography. Serum cTnT levels were measured by a third generation immunoassay method and the lowest detectable level was 0.010 ng/ml.ResultsThe cumulative doxorubicin doses were at the range of 400 and 840 mg/m2 (median 480). The time past from the last doxorubicin dose was 1–168 months (median 12). All of the patients had normal chest X‐rays, electrocardiograms, and nine patients (37.5%) had abnormal systolic or diastolic cardiac function parameters. The median cumulative doxorubicin doses of the patients with normal and abnormal echocardiographic parameters were 480 and 440 mg/m2, respectively. Serum cTnT values of 21 patients were below the detection limit (< 0.010 ng/ml). There was no statistical difference between serum cTnT levels of the patients with normal and abnormal echocardiographic findings (P = 0.376).ConclusionsNo correlation was found between serum cTnT values, cumulative doxorubicin doses, and systolic or diastolic cardiac functions. We can conclude that echocardiographic follow‐up is more reliable than serum cTnT levels for detecting subclinical cardiac toxicity. © 2003 Wiley‐Liss, Inc.
High‐dose chemotherapy with autologous stem‐cell rescue in the treatment of patients with recurrent non‐cerebellar primitive neuroectodermal tumors
Authors: Broniscer Alberto , Nicolaides Theodore P. , Dunkel Ira J. , Gardner Sharon L. , Johnson James , Allen Jeffrey C. , Sposto Richard , Finlay Jonathan L. 
Published: January 2004

AbstractBackgroundRecurrent non‐cerebellar primitive neuroectodermal tumors (PNETs) carry a dismal prognosis when treated with conventional chemotherapy alone. XSWe tested the efficacy of high‐dose chemotherapy (HDC) followed by autologous stem‐cell rescue (ASCR) in this setting.ProcedureEligibility mandated either minimal residual disease or evidence of chemosensitivity before HDC. Conditioning consisted of carboplatin (CBDCA) (500 mg/m2 or AUC = 7 mg/ml min using the Calvert formula) on days −8 to −6, thiotepa (300 mg/m2), and etoposide (250 mg/m2) on days −5 to −3. Irradiation was given post HDC selectively.ResultsAmong 17 patients treated in this study, there were eight pineoblastoma(s) (pineo), seven cortical PNETs, and two arising elsewhere. Relapse was either local (nine) or metastatic to the brain (four) or spine (four). Two patients received HDC as the sole therapy for recurrence; additionally, eight underwent surgical debulking before HDC, and nine received irradiation, including six after HDC. Median age at ASCR was 3.9 years. Two patients died of toxicity (11%) and ten experienced tumor relapse (range: 23–361 days post ASCR). Five patients with cortical PNETs remain alive disease‐free (median follow‐up: 8.3 years); four of them received irradiation post HDC. The difference in 5‐year event‐free survival (EFS) between patients with pineo and other supratentorial PNETs was significant (0 vs. 62.5 ± 17%, P = 0.0065). Both surgery at relapse and irradiation post HDC were favorable prognostic factors (P = 0.006 and 0.01, respectively).ConclusionsPatients with recurrent cortical PNETs can be cured with this strategy. Surgical debulking before, and irradiation after HDC play an important role in treatment success. © 2003 Wiley‐Liss, Inc.
Clonal proliferation of T‐Cell large granular lymphocytes
Authors: Boeckx Nancy , Uyttebroeck Anne , Langerak Anton W. , Brusselmans Caroline , Goossens Willy , Bossuyt Xavier 
Published: January 2004

AbstractBackgroundT‐cell large granular lymphocyte (T‐LGL) leukemia is a disorder only rarely reported in children. We diagnosed a new case of a clonal T‐LGL proliferation in a 6‐year‐old girl presenting with severe neutropenia and pure red blood cell aplasia (PRCA).ProcedureFlow cytometric analysis including TCR‐Vβ repertoire analysis and molecular studies using reverse transcriptase polymerase chain reaction (RT‐PCR), PCR heteroduplex analysis and GeneScan analysis were performed to investigate the clonal nature of the T‐LGL.ResultsFlow cytometric analysis revealed a Vβ3 clonal nature. Molecular studies identified a clonal Vβ3‐Cβ RT‐PCR product. Both PCR heteroduplex analysis and GeneScan analysis found clonal TCRB and TCRG gene rearrangements.ConclusionsAn underlying T‐LGL leukemia should be investigated in the diagnostic evaluation of acquired PRCA and neutropenia in young children. Both flow cytometric and molecular analyses can be used to establish the clonal nature of T‐LGL. © 2003 Wiley‐Liss, Inc.
Starting an adolescent cancer unit: Why does it take so long?
Authors: Windebank Kevin , Morgan Sue 
Published: January 2004

AbstractA pragmatic approach is discussed based on the authors' differing experiences while designing new units specifically for adolescents with cancer in Leeds and Newcastle upon Tyne. Planning and implementation are complex and very time consuming. Areas to be considered include: formally identifying needs and adapting to existing local circumstances, convening a working group and involving potential stakeholders at an early stage, designing a suitable physical space, recruiting and integrating staff to create a supportive environment, obtaining financial support, and developing operational policies. For successful running of an adolescent unit, old prejudices must be disavowed and new models of medical care considered. © 2003 Wiley‐Liss, Inc.
Treatment of CNS malignant rhabdoid tumors
Authors: Ronghe M.D. , Moss T.H. , Lowis S.P. 
Published: January 2004

AbstractBackgroundCentral Nervous System (CNS) rhabdoid tumours are a highly malignant group of neoplasms usually occurring in children under 2 years of age with characteristic histopathologic findings but unclear histiogenesis and almost uniformly fatal outcome. There is still no proven curative therapy available.ProcedureThe clinical course and the successful outcome of therapy in two children with primary CNS rhabdoid tumour are described in this context. Both children had subtotal excision of the primary tumour and received chemotherapy based on the SIOP Malignant Mesenchymal Tumour (MMT‐95) protocol with addition of triple intrathecal chemotherapy. Following this, one of the patients received high dose therapy (busulphan and thiotepa), whereas the other had craniospinal radiotherapy with a boost to the primary site.ResultsThe treatment was reasonably well tolerated and both patients are alive with no evidence of disease 52 months and 65 months after the primary diagnosis. Their favourable outcomes are compared with those of 49 others reported in the literature.ConclusionsIntensified therapy (with autologous bone marrow transplantation and intrathecal chemotherapy) may improve the prognosis of patients with malignant rhabdoid tumour. © 2003 Wiley‐Liss, Inc.
Decreasing the number of MOPP courses reduces gonadal damage in survivors of childhood hodgkin disease
Authors: van den Berg H. , Furstner F. , van den Bos C. , Behrendt H. 
Published: January 2004

AbstractBackgroundChildren treated for Hodgkin disease are at risk for gonadal damage. Since most children were treated with radiotherapy (RT) in combination with chemotherapy, the presumed detrimental effect of MOPP (mustine, vincristine, procarbazine, and prednisone) (in contrast to schemes with less or without alkylating agents) could not be discerned completely from the effects of RT.ProceduresChildren with Hodgkins disease treated without RT were included in sequential protocols containing six courses of MOPP (n = 24), six courses of ABVD (doxorubicin, bleomycin, vinblastine, and dacarbazine) (n = 17), or three courses of MOPP/ABVD (n = 35). Of these 76 patients, 48, who had completed treatment and had reached puberty, were investigated for gonadal damage.ResultsOf the male patients, 81% of MOPP treated patients had increased follicular stimulating hormone (FSH) values, in 23% luteinizing hormone (LH) values were abnormal. In ABVD treated patients, no elevated levels of FSH or LH were noted. In 30% of patients treated with MOPP/ABVD, FSH values were abnormal, but no abnormal LH values were found. Median testicular volume per group decreased in relation to a higher number of MOPP courses. Sperm analysis revealed azoospermia in nearly all MOPP treated patients. In ABVD and MOPP/ABVD treated patients both oligospermia and azoospermia were noted. The number of sperm samples were too less to make any sound conclusions. Menarche occurred in all females, however in some at a relatively later age. One female patient treated with MOPP/ABVD had a normal pregnancy.ConclusionsLimitation of MOPP therapy to three courses, in children treated without any RT, results in less gonadal damage as compared with six MOPP courses. From our data, MOPP damages Sertoli cells and may also damage Leydig cells as suggested by the higher LH values in conjunction with normal testosterone levels. © 2003 Wiley‐Liss, Inc.
Osteochondroma after total body irradiation: An age‐related complication
Authors: Taitz Jonathan , Cohn Richard J. , White Les , Russell Susan J. , Vowels Marcus R. 
Published: January 2004

AbstractBackgroundThe discovery of a mass lesion in a long‐term cancer survivor causes significant anxiety. The causes of such a mass include benign osteochondroma, which has been reported following focal irradiation and total body irradiation (TBI).ProcedureTo establish the incidence of osteochondromas following TBI, the medical records of all children treated at the Sydney Children's Hospital who received TBI as part of the conditioning prior to bone‐marrow transplantation between 1978 and 1997 were reviewed.ResultsFive of 58 children who received TBI as part of the conditioning therapy for bone‐marrow transplantation and who have been followed for at least 30 months post‐irradiation, developed osteochondromas. All five of the patients had been under 5 years of age when they received TBI (mean 2.4 years), giving an incidence of osteochondroma of 24% in those who received TBI in the first 5 years of life. No osteochondromas have been diagnosed among the 37 patients who were aged between 5 years and 15 years at the time of receiving TBI. The mean latent time to diagnosis of osteochondroma was 4.6 years (range 2.5–9 years). Two patients developed multiple osteochondromas. Two patients required resection of their osteochondromas because of symptoms. Neither showed malignant degeneration.ConclusionsYounger patients are at increased risk of osteochondroma following TBI. Review of the available literature suggests a low malignant potential of radiation‐induced osteochondromas. Knowledge about the behaviour of post‐irradiation osteochondromas will help clinicians manage patients appropriately. © 2003 Wiley‐Liss, Inc.