bluuebunny/crossref_metadata_2025 huggingface dataset:
MRI of the foot and ankle: Diagnostic performance and patient acceptance of a dedicated low field MR scanner
Authors: Verhoek Guido , Zanetti Marco , Duewell Stefan , Zollinger Hans , Hodler Juerg
Published: March 2007

The objective of this study was to compare image quality and patient acceptance of a dedicated .2‐T MR system and a 1.0‐T whole body system. Forty‐one consecutive patients referred for MRI of the foot or ankle were prospectively examined with a dedicated .2‐T low field system and a 1.0‐T whole body system. Images were evaluated qualitatively by two observers and quantitatively using signal‐difference‐to‐noise ratios. The patients were interviewed with respect to positioning, examination time, noise, claustrophobia, confidence in the diagnosis, and willingness to repeat the examination, using a questionnaire. The qualitative score was significantly higher for the 1.0‐T system (2.6 vs 2.2 for reader 1 [P = .008] and 2.6 vs 1.7 for reader 2 [P < .0001]), respectively. The signal‐difference‐to‐noise ratios were also superior for the 1.0‐T MR system (2.96 vs .88, P < .0001). However, 96% of the lesions visualized at 1.0 T were also detected with the low field system. Patient acceptance was significantly better for the 1.0‐T MR scanner (48.6 vs 43.9, P = .007). Image quality of the dedicated low field system was inferior to the 1.0‐T system using objective parameters, and patients did not prefer the low field system. Although only 4% of lesions were missed in this series, the low field MR system can only be recommended when funding is limited and the available space is limited.
Chronic lymphocytic leukemia: Changes in bone marrow composition and distribution assessed with quantitative MRI
Authors: Lecouvet Frederic E. , Berg Bruno C. Vande , Michaux Lucienne , Scheiff Jean‐Marie , Malghem Jacques , Jamart Jacques , Maldague Baudouin E. , Michaux Jean Louis , Ferrant Augustin
Published: March 2007

The purposes of this study were (α) to determine the prevalence of bone marrow abnormalities in patients with chronic lymphocytic leukemia (CLL) using quantitative MR assessment of axial marrow composition and peripheral marrow distribution; (b) to assess the agreement between both quantitative MR methods and compare their sensitivities to detect marrow alterations; and (c) to correlate MR findings with clinical and laboratory parameters. Twenty‐nine consecutive patients with biopsy‐proven CLL were investigated on a .5‐T MR imager to determine bulk T1 relaxation times of the vertebral bone marrow and proportion of proximal femur surface area occupied by nonfatty marrow on coronal T1‐weighted MR images of one hip. Of the 29 patients, 12 (41%) had abnormal increase in lumbar marrow T1 values (>600 msec) and 16 (55%) had increased proportion of surface area occupied by non‐fatty marrow in the proximal femur (>+1 SD compared to normal values determined in sex‐ and age‐matched healthy subjects). The results of both quantitative MR methods were normal in 12 patients and abnormal in 11 patients (agreement, 79%). Patients with alterations in peripheral marrow distribution had significantly higher T1 relaxation times (P = .001) than those with normal peripheral marrow. Patients with abnormal marrow composition or distribution at MRI had significantly higher blood and marrow lymphocytosis than patients without these features. In conclusion, the agreement between both quantitative MR methods suggests a parallelism between changes in axial marrow composition and in peripheral marrow distribution in patients with CLL. The limits of quantitative MRI in CLL must be kept in mind, because quantitative MR methods failed to detect leukemic marrow infiltration in 41% of patients.
An automated measurement system for characterization of RF and gradient coil parameters
Authors: Boyer Jeffrey S. , Wright Steven M. , Porter Jay R.
Published: March 2007

A fully automated laboratory‐based measurement system for characterization of coil system parameters is presented. This method uses an inexpensive personal computer (PC)‐controlled stepper motor positioning system in conjunction with a network/spectrum analyzer and an analog‐to‐digital converter (A/D) board that allows high resolution data acquisition in an unattended manner. A graphical interface was created for complete control of stepper motor movement, measurement, and data acquisition. The system is capable of performing a wide range of measurements that can, either individually or combined, characterize radiofre‐quency (RF) and gradient coils used in MRI. Measurement methods, theory, and results for conductor and shield current distributions, mutual impedance, and magnetic fields are given. Comparisons with theoretical calculations are included to validate the accuracy and utility of the system.
Placenta Accreta: MRI antenatal diagnosis and surgical correlation
Authors: Ha Taryn P. T. , Li King C. P.
Published: March 2007

We describe a case of a placenta previa accreta that was diagnosed antenatally by MRI with subsequent surgical confirmation. We show the advantages of ultrafast MRI single shot (SS) fast spin echo (FSE) techniques for accurate diagnosis with minimal scan time and fetal motion artifacts.
Dependence of apparent diffusion coefficients on axonal spacing, membrane permeability, and diffusion time in spinal cord white matter
Authors: Ford J. Chetley , Hackney David B. , Lavi Ehud , Phillips Micheal , Patel Upen
Published: March 2007

We used a numerical simulation of water self‐diffusion among permeable cylinders to predict the dependence of MR‐based apparent diffusion coefficients in white matter on axonal separation, barrier permeability, and diffusion time (T). The transverse apparent diffusion coefficient (tADC), calculated with simulated diffusion‐sensitizing gradients perpendicular to the axon fibers, remains a function of T down to diffusion times as short as .1 μsec for a range of diffusion barrier permeability. As the diffusion time lengthens, the response of tADC depends on axon diameter, with decreases in tADC occurring earliest, and most dramatically, for the smallest fiber diameter simulated (2 μm). For a given axonal separation, asymptotic values of ADC are determined by permeability alone and are the same for 2‐μm and 11‐μm fibers of equal membrane permeability. The effect of increased relative intracellular volume is manifested primarily in a decrease in tADC at short T. Increases in interaxonal spacing increase the tADC at asymptotically long diffusion times and reduce the dependence on permeability. However, at the widest plausible axonal separations, permeability remains an important determinant of tADC. These simulations may enhance interpretation of measured tADC in the context of the underlying physiologic and structural changes at the cellular level that accompany white‐matter disease.
Fast fluid‐attenuated inversion‐recovery (FLAIR) MRI in the assessment of intraaxial brain tumors
Authors: Essig Macro , Hawighorst Hans , Schoenberg Stefan O. , Engenhart‐Cabillic Rita , Fuss Martin , Debus Juergen , Zuna Ivan , Knopp Michael V. , van Kaick Gerhard
Published: March 2007

This study demonstrates the value of a fast fluid‐attenuated inversion‐recovery (FLAIR) technique in the assessment of primary intraaxial brain tumors. Twenty‐one patients with primary intraaxial brain tumors were examined by T2‐weighted, proton‐density‐weighted fast spin echo, fast FLAIR, and contrast‐enhanced T1‐weighted spin echo using identical slice parameters. The images were evaluated using quantitative and qualitative criteria. Quantitative criteria were tumor‐to‐background and tumor‐to‐cerebrospinal fluid (CSF) contrast and contrast‐to‐noise ratio (CNR). The qualitative evaluation was performed as a multi‐reader analysis concerning lesion detection, lesion delineation, and image artifacts. In the qualitative evaluation, all readers found the fast FLAIR to be superior to fast spin echo in the exact delineation of intraaxial brain tumors (P < .001) and the delineation of enhancing and nonenhancing tumor parts. Fast FLAIR was superior in the delineation of cortically located and small lesions but was limited in lesions adjacent to the ventricles. Fast FLAIR provided a significantly better tumor‐to‐CSF contrast and tumor‐to‐CSF CNR (P < .001). The tumor‐to‐background contrast and tumor‐to‐background CNR of the fast FLAIR images were lower than those of T2‐weighted spin‐echo images but higher than those of proton‐density‐weighted spin‐echo images. FLAIR images had more image artifacts influencing the image interpretation in only two patients. Signal hyperintensities at the ventricular border were present in 92% of the patients. They are common findings in fast FLAIR and should be included into the image interpretation.
In vivo validation of tissue segmentation based on a 3D feature map using both a hamster brain tumor model and stereotactically guided biopsy of brain tumors in man
Authors: Vinitski Simon , Gonzalez Carlos , Andrews David , Knobler Robert , Curtis Mark , Mohamed Feroze , Gordon Jennifer , Khalili Kamel
Published: March 2007

The purpose of this study was to validate our MR tissue segmentation technique using a hamster brain tumor model and malignant brain tumors in man. We used a multispectral tissue segmentation analysis. Three sets of MRI data were included: proton density, T2‐weighted fast spin echo, and T1‐weighted spin echo, as inputs. Three image preprocessing steps included correcting image nonuniformity, application of an anisotropic diffusion type filter, and data point selection by a qualified observer. We used the k‐Nearest Neighbor segmentation algorithm, which does not require prior knowledge of the sample distribution. This choice allowed us to optimize the different tissue clusters present in three‐dimensional (3D) feature space. In vivo validation of the technique was performed in hamsters harboring tumors induced with JC virus‐transformed HJC‐15 cells, as compared to three control animals. Human brain tumors obtained by stereotactically guided biopsy in six patients were also included in the study. Finally, brain tumors were removed from two patients who underwent conventional craniotomy using segmentation‐derived images as a guide. In the hamsters, 10 tissues were correctly identified by segmentation and were confirmed histologically (P < .02). In the patients, there was also a strong correlation between our segmentation results and the tissue obtained by stereotactic biopsy (P < .01). In one of the two patients who underwent open craniotomy, segmentation images were useful in revealing tumor spread into vital areas of the brain (motor area). In conclusion, the results of segmentation correlate well with the tissues in vivo and thus warrant further clinical utilization and evaluation.
Interleaved gradient echo planar (IGEPI) and phase contrast CINE‐PC flow measurements in the renal artery
Authors: Bock Michael , Schoenberg Stefan O. , Schad Lothar R. , Knopp Michael V. , Essig Marco , van Kaick Gerhard
Published: March 2007

ECG‐gated phase contrast (CINE‐PC) flow measurements in the renal artery help to differentiate between low‐ and high‐grade stenoses. Because conventional CINE‐PC acquisitions with high temporal resolution require acquisition times of several minutes, respiratory motion results in a systematic overestimation of renal artery flow. With the use of an interleaved gradient echo‐planar technique (IGEPI), total measurement times can be shortened to about 30 seconds, while a high spatial and temporal resolution is maintained. In this study, an IGEPI CINE‐PC flow measurement pulse sequence with 16 gradient echoes was compared with a non‐breathheld conventional CINE‐PC technique. Flow‐time curves were measured in volunteers and in patients with suspected renal artery stenosis. With IGEPI CINE‐PC, mean flow velocity, vessel cross‐sectional area, and mean blood flow were substantially lower by 9% to 25%. Contrast‐enhanced 3D MR angiography was used to compare stenosis grading based on flow‐time curve patterns with morphologic grading. With IGEPI CINE‐PC, all high‐grade stenoses (n = 5) were detected, whereas only 66% (n = 3) were found with conventional CINE‐PC.
Assessment of coronary artery patency after stent placement using magnetic resonance angiography
Authors: Duerinckx André J. , Atkinson Dennis , Hurwitz Robert
Published: March 2007

The ability to noninvasively assess the patency of coronary stents would represent a significant advance. We evaluated the safety and ability of two‐dimensional coronary MR angiography In imaging stents and suggesting patency. Coronary MR angiography of 26 coronary stents (Palmaz‐Schatz) was performed in 16 patients 39 to 73 years of age. Studies were performed between 2 and 4 months after stent placement. All patients were symptom free at the time of imaging. Coronary MR angiography was performed with a commercial 1.5‐T MR imager using an electrocardio‐graphically gated pulse sequence with breath‐holding. Images were obtained in mid‐diastole with and without fat suppression. Image artifacts caused by the metal in the stents were clearly visualized in all 26 stents (100% sensitivity for stent detection). Arterial flow signal was seen in the coronary artery or graft distal to the stent in 25 of 26 cases (96%). All patients, except for the one in which distal flow could not be seen, remained symptom free for >2 years. The distribution of stent locations was as follows: 10 in the right coronary artery (RCA), 10 in the left anterior descending coronary artery (LAD), 2 in the left circumflex coronary artery, and 4 in saphenous vein grafts (SVGs) to RCA. One patient had 2 RCA and 2 LAD stents, one had 3 RCA and 1 LAD stents, one had 3 SVG stents, and two had double RCA stents. Coronary MR angiography is safe for noninvasive imaging of coronary stents, and in the proper clinical setting, it can be used to help suggest patency.
Characterization of novel myelin components 3‐O‐acetyl‐sphingosine galactosylceramides by electrospray ionization Q‐TOF MS and MS/CID‐MS of Li+ adducts
Authors: Bennion Beau , Dasgupta Somsankar , Hogan Edward L. , Levery Steven B.
Published: March 2007

Glycosphingolipids with Rf values higher than those of monoglycosylceramides (MGCs) in normal phase HPTLC appear to be normal components of myelin. A series of such low polarity components, referred to as ‘fast moving cerebrosides’ (FMCs), have been isolated from rat brain, and two of these fractions (FMC‐1 and FMC‐2) were found to be novel derivatives of galactosylceramide (GalCer) exhibiting O‐acetylation at the 3‐hydroxy group of the sphingoid moiety, and incorporating either non‐hydroxy or 2‐hydroxy fatty‐N‐acylation (Dasgupta S, Levery SB, Hogan EL. J. Lipid Res. 2002; 43: 751–761). Similar to the parent compounds, the 3‐O‐acetyl‐sphingoid derivatives exhibit considerable diversity with respect to fatty‐N‐acyl chain length, manifested by heterogeneous molecular ion (Li+ adduct) profiles. However, a detailed analysis of the individual molecular variants (‘lipoforms’), e.g. by tandem MS/CID‐MS analysis, was not carried out. In addition, several other FMCs distinguished by even lower polarity (higher HPTLC Rf values) were isolated but have remained uncharacterized. For this study, analysis of both the known and unknown FMC components was carried out by positive ion ESI‐MS and MS/CID‐MS of their Li+ adducts on a Q‐TOF mass spectrometer. Since a Q‐TOF instrument has not yet been applied to MS of lithiated cerebrosides and FMCs, MS/CID‐MS spectra of bovine brain GalCer (both types) and the previously characterized rat brain FMCs (FMC‐1 and FMC‐2), having 3‐O‐acetylation of the sphingoid, were systematically acquired and their fragmentation behavior compared. This was followed by systematic analysis of previously uncharacterized FMC fractions (FMC‐3 through FMC‐5/6/7). The GalCer and FMC components proved to be amenable to analysis by this technique, and the data confirm that the latter are all related 3‐O‐acetyl‐sphingoid derivatives, with the higher Rf components carrying additional O‐acetyl modifications on the galactosyl residue, which further reduce their polarity. The utility of the technique, the structures of unknown FMCs, and their characteristic fragmentation patterns are described. Copyright © 2007 John Wiley & Sons, Ltd.
Dissipation of charge on MALDI‐TOF polymeric chips using an electron‐acceptor: analysis of proteins
Authors: Ibáñez Alfredo J. , Muck Alexander , Svatoš Aleš
Published: March 2007

Disposable polymeric devices used for direct sample pretreatment/signal enhancement and MALDI‐MS analyses of biomolecules suffer from the accumulation of electric charge and related positive mass shifts due to photoelectric effects on non‐conductive surfaces after irradiation with lasers. The effects of surface charging on the mass shift of protein spectra during MALDI‐TOF/MS measurements on copolymeric sample array chips were studied. Methyl viologen is used to monitor the development of charge and is demonstrated to be an effective electron scavenger. The use of such reducible species leads to increased accuracy, signal homogeneity, and resolution for mass spectral measurements of proteins in mixtures with sinapinic and 2,5‐dihydroxybenzoic (DHB) acids. This approach can be used on a wide range of nonconductive support materials. Copyright © 2007 John Wiley & Sons, Ltd.
Early Indicators of Prognosis in Fulminant Hepatic Failure
Authors: Dhiman Radha K. , Jain Sanjay , Maheshwari Uma , Bhalla Ashish , Sharma Navneet , Ahluwalia Jasmina , Duseja Ajay , Chawla Yogesh
Published: March 2007

While King's Hospital Criteria (KCH) criteria are used worldwide, the Model for End-Stage Liver Disease (MELD) is a more recently developed scoring system that has been validated as an independent predictor of patient survival in conditions for liver transplantation (LT). The aim of the present study was to compare MELD and KCH criteria with other early clinical prognostic indicators (CPI) in a cohort of patients with fulminant hepatic failure (FHF). A total of 144 patients (mean age 31.7 ± 14.7 yr; range 12–82 yr; 62 males) with FHF due to acute viral hepatitis were included into the study. Variables found significant on univariate analysis were entered into a multivariate logistic regression analysis. A total of 52 (36.1%) patients survived, the remaining 92 (63.9%) died. Univariate analysis showed that age, duration of jaundice, jaundice-encephalopathy interval (JEI), grade of encephalopathy, presence of cerebral edema, bilirubin, prothrombin time, creatinine, and MELD score were significantly different between survivors and nonsurvivors. Multivariate logistic regression identified 6 independent CPI of adverse outcome on admission: age ≥50 yr, JEI >7 days, grade 3 or 4 encephalopathy, presence of cerebral edema, prothrombin time ≥35 seconds, and creatinine ≥1.5 mg/dL. Presence of any 3 of 6 CPI was optimum in identifying survivors and nonsurvivors. A MELD score of ≥33 was found to be best discriminant between survivors and nonsurvivors by the construction of receiver operating characteristic (ROC) curves. Any 3 CPI were superior to MELD and KCH criteria in predicting the outcome (c-statistic [95% confidence interval]: CPI 0.802 [0.726–0.878], MELD 0.717 [0.636–0.789], and KCH criteria 0.676 (0.588–0.764); P values: CPI vs. MELD 0.045, CPI vs. KCH criteria 0.019, and MELD vs. KCH criteria 0.472). In conclusion, MELD and KCH criteria are not as useful as a combination of other early CPI in predicting adverse outcome in patients with FHF due to acute viral hepatitis. Liver Transpl, 2007. © 2007 AASLD.
Cirrhosis After Orthotopic Liver Transplantation in the Absence of Primary Disease Recurrence
Authors: Seyam Moataz , Neuberger James M. , Gunson Bridget K. , Hübscher Stefan G.
Published: March 2007

Liver allograft cirrhosis is a relatively uncommon complication of liver transplantation. Most cases can be attributed to disease recurrence, particularly recurrent hepatitis C. Little is known about the frequency, etiology, and natural history of liver allograft cirrhosis occurring without evidence of recurrent disease. The aim of the present study was to review the clinicopathological features in this group of patients. We retrospectively reviewed data from all adult patients who were transplanted between 1982 and 2002 and survived >12 months after orthotopic liver transplantation (n = 1,287). Cases of histologically proven cirrhosis were identified from histopathological data entered into the Liver Unit Database. A total of 48 patients (3.7%) developed cirrhosis. In 29 of them, cirrhosis could be attributed to recurrent disease (hepatitis C, 11; hepatitis B, 4; autoimmune hepatitis, 4; primary biliary cirrhosis, 2; primary sclerosing cholangitis, 3; nonalcoholic steatohepatitis, 4; alcoholic liver disease, 1). In 9 of the 19 patients without evidence of disease recurrence, another cause of cirrhosis could be identified (de novo autoimmune hepatitis, 4; biliary complications, 4; acquired hepatitis B, 1). In the remaining 10 cases, the cause of cirrhosis remained unknown; their previous biopsies had shown features of chronic hepatitis of uncertain etiology. Three patients in this group died, and the remaining 7 are alive with good graft function 3–12 years after cirrhosis was first diagnosed. The prevalence of “cryptogenic” posttransplant cirrhosis was significantly higher in patients initially transplanted for fulminant seronegative hepatitis (6%) than in those transplanted for other diseases (0.3%). In conclusion, posttransplant cirrhosis without disease recurrence is uncommon, but it is more frequent in patients transplanted for fulminant seronegative hepatitis. Chronic hepatitis is the most frequent underlying pathological process in cases where the cause of cirrhosis remains uncertain. Liver Transpl, 2007. © 2007 AASLD.
Acute Liver Failure in Spain
Authors: Escorsell Àngels , Mas Antoni , de la Mata Manuel
Published: March 2007

The cause of acute liver failure (ALF) is a major determinant of its outcome. Acetaminophen (paracetamol) overdose is a leading cause of ALF in some developed countries, whereas in others, such as Spain, it is extremely rare. To analyze the etiology, characteristics, and outcome of ALF in Spain, we performed a retrospective analysis of 267 patients whom we observed from 1992 to 2000. Seventeen tertiary-care hospitals with active liver transplantation (LT) programs contributed data. Causes of ALF were viral hepatitis in 98 (37%; hepatitis B virus in 75 patients), unknown in 86 (32%), drug or toxic reactions in 52 (19.5%; acetaminophen overdose in 6), and miscellaneous in 31 (11.6%). Overall survival was 58%. LT was performed in 150 patients, with a survival of 69%. Despite fulfilling criteria, 51 patients were not transplanted because of contraindications; their survival was only 7.8%. Forty-seven (85.5%) of 55 patients without transplant criteria survived. Hepatitis B virus is the most common cause of ALF in Spain, although the origin of 30% of cases remains undetermined. Acetaminophen overdose represents a very rare cause of ALF. LT was performed in >50% of cases. Patients without transplant criteria had a very good prognosis; those who fulfilled these criteria but who had contraindications for transplantation had a high mortality rate. Liver Transpl, 2007. © 2007 AASLD.
Effect of Polycarboxylate Blocks on the Amidase Activity of Trypsin through Complexation with PEG/Polycarboxylate Block Ionomers
Authors: Harada Atsushi , Yoshioka Yuriko , Kawamura Akifumi , Kojima Chie , Kono Kenji
Published: March 2007

The amidase reaction of trypsin, which is a member of the serine proteinase family, is accelerated by its complexation with block ionomers containing a polycarboxylate block, such as PEG‐PAA, PEG‐PGA, or PEG‐PMA. PEG‐PAA and PEG‐PGA had similar effects, causing an increase in the kcat value and a shift in the pH profile to a lower pH region. On the other hand, PEG‐PMA showed not only an increase in the kcat value, but also a decrease in the activation energy; however, there was no shift in the pH dependence of the initial reaction rate. Such differences might be induced by the difference in pKa values of the polycarboxylate block in block ionomers.

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Modification of Gelatin by Reaction with 1,6‐Diisocyanatohexane
Authors: Bertoldo Monica , Bronco Simona , Gragnoli Tania , Ciardelli Francesco
Published: March 2007

1,6‐Diisocyanatohexane and dimethyl sulfoxide were exploited as crosslinking agent and reaction solvent, respectively, for gelatin modification. Crosslinked samples were fractionated and analyzed by thermogravimetric analysis, infrared spectroscopy, acid and base titrations, and swelling measurements. The yield of crosslinking was found to increase with increasing diisocyanate and gelatin concentrations and the amount of bound crosslinker was evaluated. The chemical analysis of the reaction products allowed the process parameters to be related to the properties of the textile/gelatin composites. For this purpose poly(propylene)‐, poly(ethylene terephthalate)‐, and cotton‐based textiles were treated to prepare soft and dimensionally stable supported materials with a gel phase composed of gelatin.

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Oligosaccharide‐Modified Poly(propyleneimine) Dendrimers: Synthesis, Structure Determination, and CuII Complexation
Authors: Appelhans Dietmar , Zhong Yong , Komber Hartmut , Friedel Peter , Oertel Ulrich , Scheler Ulrich , Morgner Nina , Kuckling Dirk , Richter Sven , Seidel Jürgen , Brutschy Bernhard , Voit Brigitte
Published: March 2007

The multiple application of reductive amination on primary amino groups of first and second generation poly(propyleneimine) dendrimers is used as a one‐pot approach to introduce twice the amount of the oligosaccharide units as surface groups, compared to initially present amino groups in the first and second generation dendrimers. This was proven by 1H NMR, MALDI‐TOF‐MS, and LILBID‐MS analysis. The size of these dendrimers was determined by the hydrodynamic radius using pulsed field gradient NMR and dynamic light scattering. Molecular modeling confirmed the presence of dense‐shell dendrimers. These dendrimers exhibit a generation dependent CuII/dendrimer ratio in an aqueous environment, highlighting these materials as possible metal‐carrier systems with a well‐defined oligosaccharide protection shell for application in a biological environment.

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Interval scheduling: A survey
Authors: Kolen Antoon W.J. , Lenstra Jan Karel , Papadimitriou Christos H. , Spieksma Frits C.R.
Published: March 2007

In interval scheduling, not only the processing times of the jobs but also their starting times are given. This article surveys the area of interval scheduling and presents proofs of results that have been known within the community for some time. We first review the complexity and approximability of different variants of interval scheduling problems. Next, we motivate the relevance of interval scheduling problems by providing an overview of applications that have appeared in literature. Finally, we focus on algorithmic results for two important variants of interval scheduling problems. In one variant we deal with nonidentical machines: instead of each machine being continuously available, there is a given interval for each machine in which it is available. In another variant, the machines are continuously available but they are ordered, and each job has a given “maximal” machine on which it can be processed. We investigate the complexity of these problems and describe algorithms for their solution. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007
A saturated discrete particle model and characteristic‐based SPH method in granular materials
Authors: Li Xikui , Chu Xihua , Sheng D. C.
Published: March 2007

Based on the discrete particle model for solid‐phase deformation of granular materials consisting of dry particulate assemblages, a discrete particle–continuum model for modelling the coupled hydro‐mechanical behaviour in saturated granular materials is developed. The motion of the interstitial fluid is described by two parallel continuum schemes governed by the averaged incompressible N–S equations and Darcy's law, respectively, where the latter one can be regarded as a degraded case of the former.

Owing to the merits in both Lagrangian and mesh‐free characters, the characteristic‐based smoothed particle hydrodynamics (SPH) method is proposed in this paper for modelling pore fluid flows relative to the deformed solid phase that is modelled as packed assemblages of interacting discrete particles. It is assumed that the formulation is Lagrangian with the co‐ordinate system transferring with the movement of the solid particles. The assumed continuous fluid field is discretized into a finite set of Lagrangian (material) points with their number equal to that of solid particles situated in the computational domain. An explicit meshless scheme for granular materials with interstitial water is formulated. Numerical results illustrate the capability and performance of the present model in modelling the fluid–solid interaction and deformation in granular materials saturated with water. Copyright © 2007 John Wiley & Sons, Ltd.
Hypersingular boundary integral equations and the approximation of the stress tensor
Authors: Salvadori Alberto
Published: March 2007

The present work deals with the application of the traction hypersingular boundary integral equation to approximate the stress tensor along the boundary, by making use of unit vectors that differ from the normal at the boundary. It is proved that special care is required in the evaluation of the free terms, in order to avoid insidious and unexpected errors. Copyright © 2007 John Wiley & Sons, Ltd.
Pulmonary dendritic cells and alveolar macrophages are regulated by γδ T cells during the resolution of S. pneumoniae‐induced inflammation
Authors: Kirby AC , Newton DJ , Carding SR , Kaye PM
Published: March 2007

γδ T cells commonly associate with mucosal and epithelial sites, fulfilling a variety of immunoregulatory functions. While lung γδ T cells have well‐characterized pro‐inflammatory activity, their potential role in the resolution of lung inflammation has yet to be explored in any detail. Indeed, given the importance of minimizing inflammation, the cellular mechanisms driving the resolution of lung inflammation are poorly understood. Using a murine model of acute Streptococcus pneumoniae‐mediated lung inflammation, we now show that resolution of inflammation following bacterial clearance is associated with a > 30‐fold increase in γδ T‐cell number. Although inflammation eventually resolves in TCRδ−/− mice, elevated numbers of alveolar macrophages and pulmonary dendritic cells, and the appearance of well‐formed granulomas in lungs of TCRδ−/− mice, together indicated a role for γδ T cells in regulating mononuclear phagocyte number. Ex vivo, both alveolar macrophages and pulmonary dendritic cells were susceptible to lung γδ T cell‐mediated cytotoxicity, the first demonstration of such activity against a dendritic cell population. These findings support a model whereby expansion of γδ T cells helps restore mononuclear phagocyte numbers to homeostatic levels, protecting the lung from the consequences of inappropriate inflammation. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Patient‐initiated telephone consultations with diabetes specialist nurse: ‘hidden’ appointments?
Authors: Wilbourne JM , Wilson AE
Published: March 2007

Patient contact with the diabetes specialist nurse (DSN) is often made by telephone rather than ‘face‐to‐face’, but costs and resources required are rarely formally identified. The aim of the present study was to identify the number, duration and nature of these calls and their impact on the DSN workload, in order to help plan future care requirements for those with diabetes. Weekday calls (09.00–18.00 hr) were logged over a nine week period late in 1994. Information collected included date, time, duration of and reason for call, sex of caller, and whether insulin‐treated. Of an active clinic population of 1,400 adults, 327 calls were made requesting advice on 349 topics. The 256 calls (78%) from insulin‐users were generally of longer duration, 54% needing between five and 15 minutes. Calls concentrated on certain times of day (p<0.001) with 19% between 09.00 and 10.00 hr, and 23% between 10.00 and 11.00 hr. Of identified reasons for calls, 24% were from people recently established on insulin therapy. Other ‘popular’ topics were insulin adjustment (10%) and advice on control (13%), while calls on hypoglycaemia (4%) and for pre‐pregnancy advice (0.6%) were rarer.

We conclude that such a telephone service is heavily used in areas appropriate to DSN expertise. Its impact on the DSN workload is significant: formal training and allocation of resources would therefore seem to be indicated.
Alcoholic ketoacidosis associated with hyperglycaemia: A diagnostic dilemma
Authors: Hart SP , Frier BM
Published: March 2007

The acute presentation of alcoholic ketoacidosis accompanied by hyperglycaemia is rare, but it may lead to the misdiagnosis of metabolically decompensated Type 1 (insulin‐dependent) diabetes and to inadvertent treatment with insulin. A case of alcoholic ketoacidosis is described in which recent excessive alcohol consumption was concealed by the patient, which resulted in a diagnosis of diabetic ketoacidosis. The blood glucose concentration in alcoholic ketoacidosis may be determined by the extent to which endogenous insulin secretion is suppressed and the extent of the peripheral insulin resistance induced by alcohol and the concomitant secretion of counter‐regulatory hormones.
Multicentre study to assess quality of life and glycaemic control of Type 2 diabetic patients treated with insulin compared with oral hypoglycaemic agents
Authors: Barnett AH , Jones D Bowen , Burden AC , Janes JM , Sinclair A , Small M , Tindall H
Published: March 2007

Quality of life, glycaemic control and frequency of hypoglycaemia were compared in 93 moderate to poorly controlled Type 2 diabetes patients randomly allocated to one of three treatment groups: Group A continued on oral hypoglycaemics, Group B switched to twice‐daily fixed mixture of human insulin using a standard syringe, Group C switched to similar insulin given by a Becton‐Dickinson (B‐D) insulin pen. After 12 weeks patients in Groups B and C were changed to B‐D pen or syringe respectively for a further 12 weeks. Patients in Group A continued on oral hypoglycaemics. At entry, 12 weeks and 24 weeks, subjects completed a ‘well‐being’ and ‘satisfaction with treatment’ questionnaire. At the end of the study, patients in Groups B and C completed an ‘insulin delivery acceptability’ questionnaire.

There was no significant difference between scores for the ‘well‐being’ and ‘satisfaction with treatment’ questionnaires but, for those patients on insulin, the ‘insulin delivery acceptability’ questionnaire demonstrated a marked preference in most patients for the pen rather than the syringe as the method of insulin delivery. Patients on insulin showed an improvement overall in HbA1c, with a mean reduction of 1.46% (95% confidence interval–2.76 to −0.16%, p=0.021) compared with tablet treatment, but at the expense of an increased frequency of hypoglycaemia and weight gain.

We conclude that in ‘moderately’ controlled Type 2 diabetes there is no significant change in quality of life when patients are switched to insulin, although once on insulin, most prefer an insulin pen to a syringe. The improvement in HbA1c may, however, be of clinical significance given the increasingly powerful evidence associating good diabetes control with reduced risk of long‐term microangiopathic complications.
Audit of referrals for dietary advice from the diabetes clinic at Bedford Hospital
Authors: Blades M. , Morgan J.
Published: March 2007

An audit of people with diabetes mellitus (DM) who were referred for dietary advice from the diabetes outpatient clinic at Bedford Hospital, was made for a four‐week period against local standards. These were set at 100% of newly diagnosed DM patients to receive advice from a dietitian within a year of diagnosis, and annually thereafter.

During the audited period 183 patients were seen in the diabetes outpatient clinic by a consultant in diabetes or one of his team. Of these, 66% (121 patients) had seen a dietitian within one year of diagnosis of DM; 19% (35 patients) had been seen for a dietetic update in the last 18 months. A proportion of patients had never seen a state registered dietitian.
Counselling for patient empowerment. Guest Lecture: The 2nd Janet Kinson Lecture Delivered at a BDA Education and Care Section meeting
Authors: Brown Florence
Published: March 2007

This review article explores the concept of empowerment described in the health promotion and health education literature and relates it to the context of diabetes care and to how the nature of the communication, and thus the relationship between health professionals and patients within the consultation, can be disempowering.

A second article by Florence Brown in this issue (see Special Review Series) looks at the philosophy of person‐centred counselling and education and how the communication of that philosophy through the use of counselling skills in the diabetic consultation can facilitate self‐empowerment in people with diabetes.
Counselling in practice
Authors: Brown Florence , Coles Professor Colin
Published: March 2007

The review article ‘Counselling for patient empowerment’ (see page 189) described some of the issues in defining empowerment in the context of health, and looked at the traditional paternalistic relationship that often exists between health professionals and patients.

This article seeks to describe the person‐centred philosophy and how that philosophy, when communicated by counselling skills, can facilitate self‐empowerment in people with diabetes.
Notes designed as an aid to professional education. A very unusual case of hyperosmolar coma
Authors: Lewis MJ , Ferguson SC , Campbell IW , Nawroz IM
Published: March 2007

Hyperglycaemic coma without ketoacidosis in the diabetic patient was presumptively first recorded by Dreschfield in 18861 but it was not until 1957 that the concept of hyperosmolar non‐ketotic coma as a distinct clinical syndrome was appreciated2,3. Hyperosmolar non‐ketotic coma (HONK) occurs typically in the elderly diabetic subject. Up to 60% of diabetic patients with HONK have previously undiagnosed diabetes mellitus. In these elderly patients, there are often multiple precipitating factors with infection being the most common4. We present the case of a female with HONK and an unusual infection, the combination of which led to her sudden and unexpected death.
IDDM patients' opinions on the use of glucagon emergency kit in severe episodes of hypoglycaemia
Authors: Yanai O. , Phillip M. , Harman I. , Elitzur‐Leiberman E. , Pilpel D.
Published: March 2007

This study investigated the coping strategies of IDDM patients with mild and severe episodes of hypoglycaemia. One hundred and two IDDM patients, aged 4–62 years old, 59% male and 41% female, were interviewed by telephone using a structured questionnaire.

Most of the patients recognised the symptoms of hypoglycaemia and accordingly treated their mild episodes with either Coca Cola or fruit juice (61%), sweets (32%), milk (26%), or a slice of bread (23%). Forty two per cent of the patients treated themselves with additional chocolate, fruit or honey. While 83% of the patients reported that they had received an explanation regarding the use of the glucagon emergency kit, only 60% actually owned it. In only 19% of the patients who had ever experienced a severe episode of hypoglycaemia had this mode of treatment actually been used. Most of the patients (67%) said they would prefer the intranasal route if available and 82% assumed that the people surrounding them would prefer to administer an intranasal spray or drops in emergency hypoglycaemic situations.

We conclude that only in a small percentage of patients is subcutaneous or intramuscular glucagon used in an emergency situation, and speculate that other modes of glucagon administration such as the intranasal route would increase the use of glucagon and prevent some of the IDDM patients from waiting for the emergency paramedic teams or from being referred to hospitals.
Social and psychological implications of diabetes mellitus for a group of adolescents
Authors: Gardiner P.
Published: March 2007

The attitudes of young adults towards their diabetes were investigated. Access was via paediatric clinics in Plymouth and the study explored the adolescents' own views, using a questionnaire. Quantitative data was analysed by computer using a software package for scientific statistics (SPSS).

Unlike previous studies, attitudes proved generally positive: 97.5% felt normal or only slightly different from non‐diabetics. This correlated with how long they had had diabetes and their view of their diabetes control; 55% perceived control as excellent or good, and this related to frequency of blood‐monitoring. Only seven individuals thought their families were over‐protective.

The data suggested a series of stages of acceptance, with a period of rejection sometimes occurring one to five years after diagnosis. Ten individuals (25%) found injections trying and claimed monitoring limited spontaneity. Twelve adolescents described weight problems; these were related to gender. Twelve monitored less than once daily and 11 frequently consumed unsuitable foods. Only 14 had considered future health prospects. Thirty two would prefer to attend specialist adolescent clinics.
Blood glucose: influence of different methods for analysis and procedures for sampling
Authors: Landin‐Olsson M. , Öhlin A‐C , Agardh C‐D
Published: March 2007

Small instruments for self‐monitoring of blood glucose (BG) are now available to the patients, and a continuous quality control of these instruments is necessary. This study compared different small BG monitoring instruments with the Hemo‐Cue instrument, which in turn was compared with the Kodak Ektachem 700 XR‐C, the routine method at our laboratory. We also studied whether venous or capillary blood specimens made any difference, and the influence on the results of the time delay between sampling and analysis.

Venous and capillary blood samples were obtained from 191 diabetic patients attending an out‐patient diabetes clinic, and glucose tests were performed in three small instruments (Glucometer Elite [n=112], Accutrend [n=56] or One Touch ll[n=23]) in parallel with HemoCue (n=191) and Kodak Ektachem 700 XR‐C(n=191).

Blood glucose analysed with the small instruments often used by patients for self‐monitoring, showed a close relationship with HemoCue. However, one instrument (Accutrend) gave constantly lower values (0.7±1.0 mmol/l: p < 0.001). HemoCue was shown to be in good agreement with the routine method used at the hospital laboratory. The difference between venous and capillary samples was significant (0.12±0.57 mmol/l p < 0.001) but of no practical importance. However, the time between sampling and analysis was important, since blood glucose decreased 1.6±0.8 mmol/l after an average delay of 3.8hr. The glycolysis occurs despite correct sampling in tubes containing heparin‐fluoride.
The prevalence of chronic renal failure in known diabetic and non‐diabetic White Caucasians and South Asians
Authors: Gujral J. S. , Burden A. C. , Iqbal J. , Raymond N. T. , Botha J. L.
Published: March 2007

The prevalence of chronic renal failure (CRF) in people with diabetes mellitus is unknown. This study was undertaken to determine the prevalence of CRF in Leicestershire residents with or without diabetes mellitus in 1991. All serum creatinine values over 200 μmol/l in 1991 were abstracted from the computer records of the central laboratory serving Leicestershire residents (total population 867,521; Indo‐Asians 8.9%). Those with serum creatinine persistently raised ( > 200 μmol/l but < 500 μmol/l) were classified as having CRF. Those with serum creatinine >500 μmol/l or who were on dialysis or had been transplanted, were classified as end stage renal failure (ESRF). Those with diabetes were identified from the central diabetes register, dialysis register and consultants' notes with 100% ascertainment. The prevalence of CRF varied from 0.3/1000 (95% Cl 0.2–0.4/1000) in non‐diabetic non‐Asian females aged 0–44 years to 25.2/1000 (95% Cl 9.3–54.0/1000) in diabetic Asian males, aged >65 years.

Multivariate logistic modelling indicated that Asians and males had approximately twice the CRF prevalence of White Caucasians and females respectively, irrespective of diabetes or age. The prevalence of CRF increased with age, and having diabetes increased the CRF prevalence five‐fold in the 0–44 age group, irrespective of ethnicity or sex. The effect of diabetes was not evident in the older age groups. These findings have important implications forthe use and allocation of health care resources.
Footcare advice: what do we tell our patients and what should we tell them?
Authors: Connor H.
Published: March 2007

The objectives of this study were to investigate the extent of agreement on advice about footcare in educational leaflets intended for people with diabetes, and to evaluate the extent of agreement among healthcare professionals on what footcare advice should be given to people with diabetes. Eight footcare leaflets were examined in a cross‐sectional questionnaire study, conducted at a diabetic footcare conference in the UK, using defined criteria for comprehensibility and readability, presentation and content. Ninety one randomly selected delegates (46 chiropodists, 30 nurses, 15 doctors) took part.

Only two of the eight leaflets were found to be suitable for partially‐sighted readers. The standard of presentation was ideal in only one, and unacceptable in three leaflets. Five leaflets contained one or more contentious statements, six gave advice which was imprecise, and six contained one or more major omissions. There were 13 statements about footcare on which there was agreement among 75% or more of the delegates, and 12 statements on which agreement was less than 75%. Healthcare professionals should agree on the advice which is to be given to their patients and they should improve the quality of the educational leaflets which they provide for patients.
Prevention is better than cure. The routine examination of the feet of patients with diabetes. Part 2. Structural abnormalities
Authors: Fawcett J. , Widdows C. , Wales J. K.
Published: March 2007

This series of articles describes (with accompanying photographs) some of the more common abnormalities which a routine inspection might reveal. Some indication is given of their importance to the diabetic patient and what action the nurse or GP should take.