bluuebunny/crossref_metadata_2025 huggingface dataset:
Reproducibility of in vivo magnetic resonance imaging–based measurement of myelin water
Authors: Levesque Ives R. , Chia Charmaine L.L. , Pike G. Bruce
Published: June 2010

Purpose:

To evaluate the reproducibility of multicomponent quantitative T2 (QT2) measurements, in particular the myelin water fraction (MWF), to determine the sensitivity of this method for monitoring myelin changes in longitudinal studies and to provide a basis for correctly powering such studies.

Materials and Methods:

The de facto standard 32‐echo spin–echo imaging sequence was used throughout, and data were analyzed using regularized non‐negative least squares (NNLS) to produce T2 distributions. Three studies were conducted in healthy subjects. First, two acquisition protocols were compared in 10 subjects. Second, variability of QT2 was evaluated over same‐day scan–rescan experiments in 6 subjects. Finally, variability was quantified in a longitudinal study of 5 subjects.

Results:

A within‐subject coefficient of variation (CoV) of 12% (range 4–25%) was observed for the MWF in brain white matter (WM) regions of interest (ROIs). The geometric mean T2 was more stable, with a longitudinal CoV of 4% (range 1–6%). The choice of the geometry and repetition time of the acquisition protocol influenced the estimates of the MWF and T2 values. The choice of integration range for the short‐T2 component had a significant effect on MWF estimates, but not on reproducibility.

Conclusion:

The reproducibility of QT2 measurements using existing methods is moderate and the method can be used in longitudinal studies, with careful consideration of the methodologic variability and an appropriate group size. J. Magn. Reson. Imaging 2010; 32:60–68. © 2010 Wiley‐Liss, Inc.
Intracranial tumor response to respiratory challenges at 3.0 T: Impact of different methods to quantify changes in the MR relaxation rate R2*
Authors: Müller Andreas , Remmele Stefanie , Wenningmann Ingobert , Clusmann Hans , Träber Frank , Flacke Sebastian , König Roy , Gieseke Jürgen , Willinek Winfried A. , Schild Hans H. , Mürtz Petra
Published: June 2010

Purpose:

To compare two ΔR2* quantification methods for analyzing the response of intracranial tumors to different breathing gases. The determination of changes in the magnetic resonance imaging (MRI) relaxation rate R2* (ΔR2*), induced by hyperoxic and hypercapnic respiratory challenges, enables the noninvasive assessment of blood oxygenation changes and vasoreactivity.

Materials and Methods:

Sixteen patients with various intracranial tumors were examined at 3.0 T. The response to respiratory challenges was registered using a dynamic multigradient‐echo sequence with high temporal and spatial resolution. At each dynamic step, ΔR2* was derived in two different ways: 1) by subtraction of R2* values obtained from monoexponential decay functions, 2) by computing ΔR2* echo‐wise from signal intensity ratios. The sensitivity for detection of responding voxels and the behavior of the “global” response were investigated.

Results:

Significantly more responding voxels (about 4%) were found for method (1). The “global” response was independent from the chosen quantification method but showed slightly larger changes (about 6%) when ΔR2* was derived from method (1).

Conclusion:

Similar results were observed for the two methods, with a slightly higher detection sensitivity of responding voxels when ΔR2* was obtained from monoexponential approximation. J. Magn. Reson. Imaging 2010;32:17–23. © 2010 Wiley‐Liss, Inc.
Quantitative analysis in clinical applications of brain MRI using independent component analysis coupled with support vector machine
Authors: Chai Jyh‐Wen , Chi‐Chang Chen Clayton , Chiang Chih‐Ming , Ho Yung‐Jen , Chen Hsian‐Min , Ouyang Yen‐Chieh , Yang Ching‐Wen , Lee San‐Kan , Chang Chein‐I
Published: June 2010

Purpose:

To effectively perform quantification of brain normal tissues and pathologies simultaneously, independent component analysis (ICA) coupled with support vector machine (SVM) is investigated and evaluated for effective volumetric measurements of normal and lesion tissues using multispectral MR images.

Materials and Methods:

Synthetic and real MR data of normal brain and white matter lesion (WML) data were used to evaluate the accuracy and reproducibility of gray matter (GM), white matter (WM), and WML volume measurements by using the proposed ICA+SVM method to analyze three sets of MR images, T1‐weighted, T2‐weighted, and proton density/fluid‐attenuated inversion recovery images.

Results:

The Tanimoto indexes of GM/WM classification in the normal synthetic data calculated by the ICA+SVM method were 0.82/0.89 for data with 0% noise level. As for clinical MR data experiments, the ICA+SVM method clearly extracted the normal tissues and white matter hyperintensity lesions from the MR images, with low intra‐ and inter‐operator coefficient of variations.

Conclusion:

The experiments conducted provide evidence that the ICA+SVM method has shown promise and potential in applications to classification of normal and pathological tissues in brain MRI. J. Magn. Reson. Imaging 2010;32:24–34. © 2010 Wiley‐Liss, Inc.
Cartilage morphology at 3.0T: Assessment of three‐dimensional magnetic resonance imaging techniques
Authors: Chen Christina A. , Kijowski Richard , Shapiro Lauren M. , Tuite Michael J. , Davis Kirkland W. , Klaers Jessica L. , Block Walter F. , Reeder Scott B. , Gold Garry E.
Published: June 2010

Purpose:

To compare six new three‐dimensional (3D) magnetic resonance (MR) methods for evaluating knee cartilage at 3.0T.

Materials and Methods:

We compared: fast‐spin‐echo cube (FSE‐Cube), vastly undersampled isotropic projection reconstruction balanced steady‐state free precession (VIPR‐bSSFP), iterative decomposition of water and fat with echo asymmetry and least‐squares estimation combined with spoiled gradient echo (IDEAL‐SPGR) and gradient echo (IDEAL‐GRASS), multiecho in steady‐state acquisition (MENSA), and coherent oscillatory state acquisition for manipulation of image contrast (COSMIC). Five‐minute sequences were performed twice on 10 healthy volunteers and once on five osteoarthritis (OA) patients. Signal‐to‐noise ratio (SNR) and contrast‐to‐noise ratio (CNR) were measured from the volunteers. Images of the five volunteers and the five OA patients were ranked on tissue contrast, articular surface clarity, reformat quality, and lesion conspicuity. FSE‐Cube and VIPR‐bSSFP were compared to IDEAL‐SPGR for cartilage volume measurements.

Results:

FSE‐Cube had top rankings for lesion conspicuity, overall SNR, and CNR (P < 0.02). VIPR‐bSSFP had top rankings in tissue contrast and articular surface clarity. VIPR and FSE‐Cube tied for best in reformatting ability. FSE‐Cube and VIPR‐bSSFP compared favorably to IDEAL‐SPGR in accuracy and precision of cartilage volume measurements.

Conclusion:

FSE‐Cube and VIPR‐bSSFP produce high image quality with accurate volume measurement of knee cartilage. J. Magn. Reson. Imaging 2010;32:173–183. © 2010 Wiley‐Liss, Inc.
Two‐dimensional MR spectroscopy of minimal hepatic encephalopathy and neuropsychological correlates in vivo
Authors: Singhal Aparna , Nagarajan Rajakumar , Hinkin Charles H. , Kumar Rajesh , Sayre James , Elderkin‐Thompson Virginia , Huda Amir , Gupta Rakesh K. , Han Steven‐Huy , Thomas M. Albert
Published: June 2010

Purpose:

To evaluate regional cerebral metabolic and structural changes in patients with minimal hepatic encephalopathy (MHE) using two‐dimensional (2D) MR spectroscopy (MRS) and T‐weighted MRI, to correlate the observed MR changes with neuropsychological (NP) test scores, and to compare the diagnostic accuracy of MRI, 2D MRS, and NP tests in discriminating between patients and healthy subjects.

Materials and Methods:

Thirty‐three MHE patients and 30 healthy controls were investigated. The 2D localized correlated spectroscopy (L‐COSY) was performed in the frontal and occipital brain on a 1.5 Tesla (T) MR scanner. The NP test battery included 15 tests, grouped into 6 cognitive domains. Globus pallidus signal intensities were calculated from T1‐weighted images.

Results:

The 2D MRS showed significant differences in ratios of the following metabolite(s) peaks with respect to creatine (Cr): decreased myo‐inositol (mI), choline (Ch), mICh, and increased (glutamate plus glutamine) (Glx) in patients compared with healthy subjects in both occipital and frontal lobes. Frontal lobe taurine also showed a decline in patients. The NP test results revealed declines in cognitive speed, motor function, executive function, and global cognitive status. Significant correlations were found between the altered metabolites and NP tests. Alteration in the mICh/Cr ratio was noted as a powerful discriminant between healthy subjects and the patients.

Conclusion:

The study demonstrates that relative metabolite levels determined by 2D MRS, in particular mICh/Cr, provide the best diagnostic prediction for MHE. The results suggest that depletions of myo‐inositol, choline and taurine with respect to creatine correlate with measures of neuropsychological impairment. J. Magn. Reson. Imaging 2010;32:35–43. © 2010 Wiley‐Liss, Inc.
Iterative image reconstruction for PROPELLER‐MRI using the nonuniform fast fourier transform
Authors: Tamhane Ashish A. , Anastasio Mark A. , Gui Minzhi , Arfanakis Konstantinos
Published: June 2010

Purpose:

To investigate an iterative image reconstruction algorithm using the nonuniform fast Fourier transform (NUFFT) for PROPELLER (Periodically Rotated Overlapping ParallEL Lines with Enhanced Reconstruction) MRI.

Materials and Methods:

Numerical simulations, as well as experiments on a phantom and a healthy human subject were used to evaluate the performance of the iterative image reconstruction algorithm for PROPELLER, and compare it with that of conventional gridding. The trade‐off between spatial resolution, signal to noise ratio, and image artifacts, was investigated for different values of the regularization parameter. The performance of the iterative image reconstruction algorithm in the presence of motion was also evaluated.

Results:

It was demonstrated that, for a certain range of values of the regularization parameter, iterative reconstruction produced images with significantly increased signal to noise ratio, reduced artifacts, for similar spatial resolution, compared with gridding. Furthermore, the ability to reduce the effects of motion in PROPELLER‐MRI was maintained when using the iterative reconstruction approach.

Conclusion:

An iterative image reconstruction technique based on the NUFFT was investigated for PROPELLER MRI. For a certain range of values of the regularization parameter, the new reconstruction technique may provide PROPELLER images with improved image quality compared with conventional gridding. J. Magn. Reson. Imaging 2010;32:211–217. © 2010 Wiley‐Liss, Inc.
Effect of Gd‐EOB‐DTPA on T2‐weighted and diffusion‐weighted images for the diagnosis of hepatocellular carcinoma
Authors: Saito Kazuhiro , Araki Yoichi , Park Jinho , Metoki Ryo , Katsuyama Hiroaki , Nishio Ryota , Kakizaki Dai , Moriyasu Fuminori , Tokuuye Koichi
Published: June 2010

Purpose:

To evaluate the effect of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd‐EOB‐DTPA) on T2‐weighted imaging (T2WI) and diffusion‐weighted imaging (DWI) for the diagnosis of hepatocellular carcinoma (HCC).

Materials and Methods:

The phantom signal intensity was measured. We also evaluated 72 patients including 30 patients with HCC. T2WI and DWI were obtained before and then 4 and 20 min after injecting the contrast medium. The signal to noise ratio (SNR), contrast to noise ratio (CNR), and apparent diffusion coefficient (ADC) were calculated in the tumor and liver parenchyma.

Results:

The phantom signal intensity increased on T2WI at a concentration of contrast medium less than 0.2 mmol/L but decreased when the concentration exceeded 0.4 mmol/L. SNR of the liver parenchyma on T2WI was significantly different between before and 4 min after injecting the contrast medium, while there were no significant differences between before and 4 and 20 min after injection. On T2WI, SNR, and CNR of HCC showed no significant differences at any time. SNR, CNR, and ADC of the liver parenchyma and tumor on DWI also showed no significant differences at any time.

Conclusion:

It is acceptable to perform T2WI and DWI after injection of Gd‐EOB‐DTPA for the diagnosis of HCC. J. Magn. Reson. Imaging 2010;32:229–234. © 2010 Wiley‐Liss, Inc.
Magnetic resonance histologic correlation in rotator cuff tendons
Authors: Buck Florian M. , Grehn Holger , Hilbe Monika , Pfirrmann Christian W.A. , Manzanell Silvana , Hodler Juerg
Published: June 2010

Purpose:

To relate histologic changes in rotator cuff tendons to the appearance on T1‐weighted as well as fat‐suppressed T2‐weighted and proton density‐weighted magnetic resonance imaging (MRI) sequences.

Materials and Methods:

T1‐weighted, fat‐suppressed T2‐weighted and fat‐suppressed proton density‐weighted sequences of 18 cadaveric shoulders were acquired. The supraspinatus, infraspinatus, and subscapularis tendons were evaluated histologically. Twenty‐six abnormalities were found in 23 of 37 tendons. In addition, histologically normal tendon parts (n = 32), including three segments with normal histology but abnormal MR signal, considered to represent magic angle effects, were defined. All regions of interest (ROIs) were evaluated by two musculoskeletal radiologists independently and blinded to histology.

Results:

In the 26 areas with anatomically intact tendons but abnormal histological findings mucoid degeneration (n = 13), chondroid metaplasia (n = 11), fatty infiltration (n = 1), and foreign‐body granuloma (n = 1) after tendon suture were found. Compared to normal tendon, mucoid degeneration was hyperintense on T2‐weighted fat‐suppressed (P = 0.007) and on proton density‐weighted fat‐suppressed images (P = 0.006). Chondroid metaplasia was hyperintense compared to normal tendon in all sequences (P < 0.05). Mucoid degeneration was hypointense compared to chondroid metaplasia on T2‐weighted fat‐suppressed images (P = 0.038) and hypointense compared to magic angle artifacts on T1‐weighted images (P = 0.046).

Conclusion:

Chondroid metaplasia of rotator cuff tendons appears to be more common than expected. Both mucoid degeneration and chondroid metaplasia may explain increased tendon signal on MR images of the rotator cuff. J. Magn. Reson. Imaging 2010;32:165–172. © 2010 Wiley‐Liss, Inc.
Visualization of cerebral microbleeds with dual‐echo T2*‐weighted magnetic resonance imaging at 7.0 T
Authors: Conijn Mandy M.A. , Geerlings Mirjam I. , Luijten Peter R. , Zwanenburg Jaco J.M. , Visser Fredy , Biessels Geert Jan , Hendrikse Jeroen
Published: June 2010

Purpose:

To assess the visualization of cerebral microbleeds with dual echo T2*‐weighted imaging at 7.0 T magnetic resonance imaging (MRI).

Materials and Methods:

Ten consecutive participants (eight men, two women, mean age 54 ± 12 years) with vascular disease or risk factors from the second manifestations of arterial disease (SMART) study were included. Dual‐echo T2*‐weighted scans (echo time: 2.5/15.0 msec) were made for all participants at 7.0 T MRI. The number of visible microbleeds and the diameter of the microbleeds were recorded on minimal intensity projection images of both echoes.

Results:

The first echo image shows dark microbleeds against a homogeneous, more hyperintense signal of the brain tissue without contrast for veins and basal ganglia. In eight patients microbleeds were observed, with a total of 104 microbleeds. Of these, 88 (84.6%) were visible on the first and 102 (98.0%) on the second echo. The mean diameter of the microbleeds was 1.24 mm for the first echo and 2.34 mm for the second echo.

Conclusion:

T2*‐weighted imaging at two echo times at 7.0 T combines the advantages of the first and second echo. Microbleeds visible on the first echo show large contrast with the surrounding tissue, even in the presence of paramagnetic ferritin. The second echo enables visualization of smaller microbleeds than the first echo. J. Magn. Reson. Imaging 2010;32:52–59. © 2010 Wiley‐Liss, Inc.
Reproducibility of black blood dynamic contrast‐enhanced magnetic resonance imaging in aortic plaques of atherosclerotic rabbits
Authors: Calcagno Claudia , Vucic Esad , Mani Venkatesh , Goldschlager Gregg , Fayad Zahi A.
Published: June 2010

Purpose:

To investigate the short‐term reproducibility of black‐blood dynamic contrast‐enhanced (DCE) magnetic resonance imaging (MRI) in atherosclerotic rabbits to evaluate the potential of this technique to be a reliable readout of plaque progression and/or regression upon therapeutic intervention.

Materials and Methods:

Atherosclerotic rabbits were imaged at baseline and 24 hours later with DCE‐MRI on a 1.5T MRI system. DCE‐MRI images were analyzed by calculating the area under the signal intensity versus time curve (AUC). Intraclass correlation coefficients (ICCs) were used to evaluate interscan, intraobserver, and interobserver reproducibility. In addition, the test–retest coefficient of variation (CoV) was evaluated.

Results:

Statistical analyses showed excellent interscan, intraobserver, and interobserver agreement. All ICCs were greater than 0.75, P < 0.01 indicating excellent agreement between measurements.

Conclusion:

Experimental results show good interscan and excellent intra‐ and interobserver reproducibility, suggesting that DCE‐MRI could be used in preclinical settings as a read‐out for novel therapeutic interventions for atherosclerosis. This preliminary work encourages investigating the reproducibility of DCE‐MRI also in clinical settings, where it could be used for monitoring high‐risk patients and in longitudinal clinical drug trials. J. Magn. Reson. Imaging 2010;32:191–198. © 2010 Wiley‐Liss, Inc.
Diffusion tensor imaging of the pediatric optic nerve: Intrinsic and extrinsic pathology compared to normal controls
Authors: Nickerson Joshua P. , Salmela Michael B. , Koski Chris J. , Andrews Trevor , Filippi Christopher G.
Published: June 2010

Purpose:

To establish normative magnetic resonance diffusion tensor imaging (MRDTI) data in the pediatric optic nerve and compare to pathologic conditions both intrinsic and extrinsic to the anterior optic nerve pathway.

Materials and Methods:

A retrospective analysis of MRDTI at 3.0T in children ages 0–18 with both normal imaging studies and with pathologic conditions either arising from the optic nerves or exerting mass effect on the anterior optic pathways was performed. Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values were obtained within the posterior part of the intraorbital optic nerves. Statistical analysis compared normal controls to optic pathway lesions.

Results:

Lesions intrinsic to the optic nerve including septo‐optic dysplasia and optic nerve glioma demonstrated statistically significant reductions in FA and increases in ADC values. There was no statistically significant difference in FA or mean diffusivity between the normal controls and patients with lesions extrinsic to the optic nerve but exerting mass effect on the visual pathway.

Conclusion:

MRDTI is a feasible technique for evaluating the optic nerves in pediatric patients. It may play a role in presurgical planning by demonstrating integrity of the visual pathway in patients with resectable lesions, allowing for minimization of morbidity associated with vision loss. J. Magn. Reson. Imaging 2010;32:76–81. © 2010 Wiley‐Liss, Inc.
Microstructural changes in patients with progressive supranuclear palsy: A diffusion tensor imaging study
Authors: Wang JiunJie , Wai YauYau , Lin Wey‐Yil , Ng ShuHang , Wang Chi‐Hong , Hsieh RenHsiang , Hsieh ChungHuang , Chen Rou‐Shayn , Lu Chin‐Song
Published: June 2010

Purpose:

To determine whether progressive supranuclear palsy (PSP) is associated with specific diffusion tensor imaging (DTI) patterns of diffusivity, anisotropy, and coherence in functionally relevant brain areas.

Materials and Methods:

In all, 17 PSP patients and 17 controls were scanned using a 3 T magnetic resonance imaging (MRI) scanner. Patients were assessed in the off‐medication condition using the Hoehn and Yahr staging and the United Parkinson's Disease Rating Scale, motor subscale (UPDRS‐III). Diffusion information were analyzed in relation to disease severity and subtypes.

Results:

Numerous changes in diffusion properties were identified in the subcortical areas. In the midbrain, fractional anisotropy (FA) decreased and MD (mean diffusivity) increased with disease progression. UPDRS‐III scores correlated positively with both FA in the caudate and MD in the pons. DTI analysis of disease subtypes demonstrated significant differences between PSP‐Parkinsonism and Steele‐Richardson‐Olszewski syndrome in axial diffusivity values in the putamen and globus pallidus, as well as in intervoxel diffusion coherence values in the middle cerebellar peduncle.

Conclusion:

Our findings, cautiously interpreted, demonstrate the advantage of using a functional imaging technique to aid in the specificity of defining more precisely the pathological processes taking place in white and gray matter regions in PSP. J. Magn. Reson. Imaging 2010;32:69–75. © 2010 Wiley‐Liss, Inc.
Genotype X/C recombinant (putative genotype I) of hepatitis B virus is rare in Hanoi, Vietnam—genotypes B4 and C1 predominate
Authors: Thuy Phung Thi Bich , Alestig Erik , Liem Nguyen Thanh , Hannoun Charles , Lindh Magnus
Published: June 2010

There are eight known genotypes of hepatitis B virus, A–H, and several subgenotypes, with rather well‐defined geographic distributions. HBV genotypes were evaluated in 153 serum samples from Hanoi, Vietnam. Of the 87 samples that could be genotyped, genotype B was found in 67 (77%) and genotype C in 19 (22%). All genotype C strains were of subgenotype C1, and the majority of genotype B strains were B4, while a few were B2. The genotype X/C recombinant strain, identified previously in Swedish patients of indigenous Vietnamese origin, was found in one sample. This variant, proposed to be classified as genotype I, has been found recently also by others in Vietnam and Laos. The current study indicates that the genotype X/C recombinant may represent approximately 1% of the HBV strains circulating in Vietnam. J. Med. Virol. 82:1327–1333, 2010. © 2010 Wiley‐Liss, Inc.
Comparison of the levels of human herpesvirus 6 (HHV‐6) DNA and cytokines in the cerebrospinal fluid and serum of children with HHV‐6 encephalopathy
Authors: Kawabe Shinji , Ito Yoshinori , Ohta Rieko , Sofue Ayako , Gotoh Kensei , Morishima Tsuneo , Kimura Hiroshi
Published: June 2010

Primary human herpesvirus‐6 (HHV‐6) infection is a common cause of acute sporadic encephalopathy in Japanese children. Occasionally, HHV‐6 is not detected in the cerebrospinal fluid (CSF) of patients with encephalopathy, for example, in those with focal viral encephalitis, such as herpes simplex viral encephalitis. This indicates that HHV‐6 encephalopathy is caused by an indirect mechanism, although this is not fully understood. HHV‐6 DNA, cytokines (interleukin (IL)‐1β, IL‐6, IL‐8, IL‐10, IL‐12 p70, tumor necrosis factor‐α, interferon‐γ), and matrix metalloproteinase‐9 were quantitated in both the CSF and serum of 13 patients with HHV‐6 encephalopathy during the acute phase of the disease. HHV‐6 DNA was detected in the CSF of seven patients with HHV‐6 encephalopathy. The viral DNA concentration was significantly higher in serum than in CSF (mean 1.64 × 104 vs. 5.70 × 101 copies/ml; P = 0.003). The lack or low level of viral DNA in the CSF samples suggests that direct invasion of the central nervous system by HHV‐6 is not the main cause of encephalopathy. Additionally, the IL‐10 concentration was significantly higher in serum than in CSF (P < 0.001), whereas there was no significant difference in IL‐6 levels between the CSF and serum samples. Interestingly, the IL‐8 concentration was significantly higher in CSF than in serum (P = 0.038). The distribution of these cytokines differed between CSF and serum. The high CSF concentration of IL‐8 could play an important role in the pathogenesis of encephalopathy. J. Med. Virol. 82:1410–1415, 2010. © 2010 Wiley‐Liss, Inc.
Clinical evaluation of the NS1 antigen‐capture ELISA for early diagnosis of dengue virus infection in Brazil
Authors: Castro‐Jorge Luiza A. , Machado Paula R.L. , Fávero Camila A. , Borges Marcos C. , Passos Luzia M.R. , de Oliveira Rosana Moreira , Fonseca Benedito A.L.
Published: June 2010

The fact that the diagnosis of infection with dengue virus is usually made by detecting IgM antibodies during the convalescent phase of the disease interferes with disease management and, consequently, with reducing mortality rates. This study evaluated the sensitivity and specificity of detection of NS1 in samples of patients suspected of acute dengue virus infection in Brazil. The results were used to institute treatment and the sensitivity and specificity of detection of NS1 were compared to the results of detection of IgM, virus isolation, and RT‐PCR. Detection of NS1 yielded better results than RT‐PCR and virus isolation. When considering IgM detection and RT‐PCR positive results as “gold standards,” the sensitivity and specificity of the NS1 assay were 95.9% and 81.1%, respectively. All patients enrolled in the study were treated promptly and had an uneventful course of the disease. The detection of NS1 provided better results than the diagnostic techniques used currently during the acute phase of disease (RT‐PCR and virus isolation). Detection of NS1 is an important tool for the diagnosis of acute dengue infection, particularly in highly endemic areas, allowing for rapid treatment of patients and reduction of disease burden. J. Med. Virol. 82:1400–1405, 2010. © 2010 Wiley‐Liss, Inc.
Poor performance of hepatitis C antibody tests in hospital patients in Uganda
Authors: Seremba E. , Ocama P. , Opio C.K. , Kagimu M. , Thomas D.L. , Yuan H.J. , Attar N. , Lee W.M.
Published: June 2010

Most hepatitis C testing in Uganda is performed using commercial rapid strip assays (RSA) to detect antibodies to hepatitis C virus (anti‐HCV), rather than enzyme immunoassays (EIA). The prevalence of hepatitis C antibodies in a Ugandan hospital population was determined using both methods to test their accuracy using nucleic acid testing (NAT) as a reference. Sera from 380 consecutive hospitalized Ugandan patients were tested for anti‐HCV using an RSA in Uganda, with subsequent automated third‐generation EIA testing in the United States, followed by NAT. Recombinant immunoblot assays (RIBA) were used as a supplementary test to detect anti‐HCV epitopes. Overall, anti‐HCV was detected in 48/380 (13%) by one or both antibody tests. Anti‐HCV was detected in 19 (5.0%) patients by RSA and in 33 (8.7%) patients by EIA; only four patients were anti‐HCV positive by both methods. Fourteen of the 48 anti‐HCV positive patients had detectable serum HCV RNA, 7 each by bDNA assay or by PCR. RSA detected only 7 of 14 HCV RNA positive sera. Of 29 RNA negative but anti‐HCV positive patients tested by RIBA, only two were anti‐HCV positive; 27 were anti‐HCV negative or indeterminate. Anti‐HCV testing by RSA and/or EIA was neither sensitive nor specific for detection of ongoing HCV infection in hospitalized Ugandan patients. Our findings underscore the importance of confirmatory nucleic acid testing, which, despite its increased cost, appears essential to manage African patients with HCV. J. Med. Virol. 82:1371–1378, 2010. © 2010 Wiley‐Liss, Inc.
Low level myocardial parvovirus B19 persistence is a frequent finding in patients with heart disease but unrelated to ongoing myocardial injury
Authors: Lotze Ulrich , Egerer Renate , Glück Brigitte , Zell Roland , Sigusch Holger , Erhardt Christian , Heim Albert , Kandolf Reinhard , Bock Thomas , Wutzler Peter , Figulla Hans‐R.
Published: June 2010

While myocardial parvovirus B19 (B19V), aside from enteroviruses (EV) and adenoviruses (ADV), has recently been found often in patients with myocarditis and idiopathic dilated cardiomyopathy (IDC), the pathogenetic significance of B19V genomes in those patients has not yet been sufficiently elucidated. In the present study, left ventricular endomyocardial biopsies from 24 patients with left ventricular ejection fraction (LVEF) below 55% due to IDC, and tissue from the right atrial appendage of 10 control patients undergoing bypass surgery with normal LVEF (>55%) were investigated for B19V, ADV, and EV genomes by specific nested polymerase chain reaction (PCR), by real time PCR or by reverse‐transcription PCR, respectively. The myocardial tissue samples from the 10 controls were analyzed each in three different virological laboratories for B19V. In the IDC group, the frequency of the myocardial virus genomes found in 54% (13/24) of the patients was as follows: B19V: 50% (12/24), EV: 8% (2/24), including one patient with B19V and EV, and ADV: 0% (0/24). For comparison, the prevalence of B19V genomes was between 30% and 60% in the control group as detected in three different laboratories, but all these control subjects were EV‐ and ADV‐negative. The number of B19V gene copies, however, was very low and similar both in the IDC and control group. In the majority of patients myocardial B19V persistence was associated with a low virus load irrespective of the underlying heart disease so that it may be of no importance in the pathogenesis of IDC. J. Med. Virol. 82:1449–1457, 2010. © 2010 Wiley‐Liss, Inc.
Correlation of HTLV‐1 Tax genetic diversity with HTLV‐1 associated myelopathy/tropical spastic paraparesis progression and HTLV‐1a genotypes in an HTLV‐1 endemic region in Argentina
Authors: Iñiguez Alena Mayo , Gastaldello René , Otsuki Koko , Balangero Marcos , Carvalho Costa Filipe , Remondegui Carlos , Paula Vicente Ana Carolina , Gallego Sandra
Published: June 2010

The oncoprotein Tax was characterized genetically from a large cohort of human T‐cell lymphotropic virus type 1 (HTLV‐1) seropositive individuals from the most endemic region of HTLV‐1‐associated myelopathy/tropical spastic paraparesis (HAM/TSP) and HTLV‐1 infection in Argentina, the province of San Salvador de Jujuy. Sixteen HAM/TSP patients and 47 HTLV‐1 healthy carriers were evaluated. Six Tax genetic polymorphisms were identified and observed in 70.8% of healthy carriers and 62.5% of HAM/TSP patients. Tax genetic polymorphisms were not associated with clinical status but A8344C polymorphism statistically provide a borderline protective effect of HAM/TSP outcome. Nucleotide diversity in healthy carriers was 0.00549, whereas HAM/TSP virus population revealed a low diversity of 0.00379, suggests a positive selection for Tax protein conservation in this group. It is concluded that tax genetic polymorphisms do not increase the risk of developing HAM/TSP in this endemic region. However, in spite of the low prevalence of HTLV‐1aB genotype, statistical analysis revealed an important correlation of tax genetic signatures with HTLV‐1aA trans‐continental subgroup. J. Med. Virol. 82:1438–1441, 2010. © 2010 Wiley‐Liss, Inc.
Hydrogen production from a PV/PEM electrolyzer system using a neural‐network‐based MPPT algorithm
Authors: Nafeh Abd El‐Shafy A.
Published: June 2010

The electrolysis of water using a polymer electrolyte membrane (PEM) electrolyzer is a very vital and efficient method of producing hydrogen (H2). The performance of this method can be significantly improved if a photovoltaic (PV) array, with maximum‐power‐point (MPP) tracker, is utilized as an energy source for the electrolyzer. This paper suggests a stand‐alone PV/PEM electrolyzer system to produce pure hydrogen. The paper also develops the different mathematical models for each constituent subsystem. Moreover, the paper develops the suitable maximum‐power‐point tracking (MPPT) algorithm that is based on utilizing the neural network. This algorithm is utilized together with the action of the PI controller to improve the performance of the suggested stand‐alone PV/PEM electrolyzer system through maximizing the hydrogen production rate for every instant. Finally, the suggested hydrogen production system is simulated using the Matlab/Simulink and neural network toolbox. The simulation results of the system indicate the improved relative performance of the suggested hydrogen production system compared with the traditional case of direct connection between the PV array and the PEM electrolyzer. Copyright © 2010 John Wiley & Sons, Ltd.
Rain day frequency and mean daily rainfall intensity as determinants of total rainfall over the eastern Orange free state
Authors: Harrison M. S. J.
Published: June 2010

Summer rainfall totals over the eastern Orange Free State are described in terms of number of days of rain and of mean rainfall per rain day. Variations in rainfall may be considered to result from frequency changes in an objectively‐chosen subset of significant rain days. It is demonstrated, through the use of the equation y = αx exp (βx) (where x and y are the cumulative percentages of the number of rain days and of the rainfall respectively), that increases in mean rainfall per rain day result from an increased number of, and increased intensity of rain on, the heaviest rain days. Some implications of these findings for studies of atmospheric circulation changes and for weather modification are discussed.
Recent studies on Carpathian Meteorology and climatology
Authors: Obrebska‐Starkel Barbara
Published: June 2010

This paper reviews the themes of the XIth, XIIth, and XIIIth International Conferences on Carpathian Meteorology. Numerous significant papers related to the following problems are presented:

impact of the mountains upon meteorological processes in the boundary layer of the atmosphere and the modelling of these processes;

hydrodynamic and synoptic methods of weather analysis and forecasting in mountainous regions;

climatic characteristics of the Carpathians and their application in practice;

secular climatic changes in the Carpathians.
Asymptotic analysis, regularisation and stable numerical solutions for heavily loaded line EHL contacts
Authors: Kudish Ilya I.
Published: June 2010

An analytical analysis of a line thermal EHL contact under heavily loaded conditions is proposed. The analysis is based on regular matched asymptotic expansions. In particular, a case of relatively small ratio of rolling and sliding frictional stresses is considered. The problem is reduced to an analogue of the isothermal EHL problem by eliminating lubricant temperature from the problem formulation. The further asymptotic and numerical analysis is very similar to the case of the isothermal EHL problem. Copyright © 2010 John Wiley & Sons, Ltd.
On Some Sharp Reversed Hölder and Hardy Type Inequalities
Authors: Bergh Jöran , Burenkov Victor , Persson Lars Erik
Published: June 2010

We discuss some reversed Hölder inequalities yielding for functions on R+ satisfying one or two conditions of quasi‐monotonicity. All cases of equality are pointed out. By using these results and some recent results by the present authors (see [3]), we prove some new reversed inequalities of Hardy type for quasi‐monotone functions. In some cases we obtain the best constants and all cases of equality are obtained. Some applications, open questions and the relations to other similar results are pointed out.
Spaces with Almost Strictly Totally Positive Bases
Authors: Carnicer J. M. , Peña J. M.
Published: June 2010

In spline spaces there are often totally positive bases possessing a strong property called almost strictly total positivity. In this paper, it is proved that, for totally positive bases of continuous functions B, the following concepts are equivalent: (i) B is almost strictly totally positive, (ii) B satifies a Schoenberg‐Whitney Theorem, (iii) The functions in B are locally linearly independent. Some classical examples of almost strictly totally positive bases are given, completing the knowledge of their properties known in the mathematical literature. Some criteria to know the existence of almost strictly totally positive bases are also derived.
Enhancing African meteorological services with MDD
Authors: Sear C. B. , Griggs D. J. , Wooster M. , Williams J. B. , Budgen P. , Trigg S. N.
Published: June 2010

Four Meteorological Data Distribution (MDD) systems were installed in African meteorological services in late 1992. The PC‐based systems are inexpensive and are intended to he sustainable technology. The MDDs were well received and in each country the MDD immediately enhanced the local information base, improving the quantity of station data available as well as providing processed products. The MDDs have enabled the recipient meteorological departments to improve the services they offer to government, to aviation and to the public. The Natural Resources Institute (NRI) is now working with local users to develop further applications. The future of MDD in Africa is not yet clear. MDD may be integrated into multi‐tasking workstations but such technology may not yet be appropriate for small meteorological services.
High‐performance computing MRI simulations
Authors: Stöcker Tony , Vahedipour Kaveh , Pflugfelder Daniel , Shah N. Jon
Published: June 2010

A new open‐source software project is presented, JEMRIS, the Jülich Extensible MRI Simulator, which provides an MRI sequence development and simulation environment for the MRI community. The development was driven by the desire to achieve generality of simulated three‐dimensional MRI experiments reflecting modern MRI systems hardware. The accompanying computational burden is overcome by means of parallel computing. Many aspects are covered that have not hitherto been simultaneously investigated in general MRI simulations such as parallel transmit and receive, important off‐resonance effects, nonlinear gradients, and arbitrary spatiotemporal parameter variations at different levels. The latter can be used to simulate various types of motion, for instance. The JEMRIS user interface is very simple to use, but nevertheless it presents few limitations. MRI sequences with arbitrary waveforms and complex interdependent modules are modeled in a graphical user interface–based environment requiring no further programming. This manuscript describes the concepts, methods, and performance of the software. Examples of novel simulation results in active fields of MRI research are given. Magn Reson Med 64:186–193, 2010. © 2010 Wiley‐Liss, Inc.
Four‐dimensional spectral‐spatial RF pulses for simultaneous correction of B1+ inhomogeneity and susceptibility artifacts in T2*‐weighted MRI
Authors: Yang Cungeng , Deng Weiran , Alagappan Vijayanand , Wald Lawrence L. , Stenger V. Andrew
Published: June 2010

Susceptibility artifacts and excitation radiofrequency field B1+ inhomogeneity are major limitations in high‐field MRI. Parallel transmission methods are promising for reducing artifacts in high‐field applications. In particular, three‐dimensional RF pulses have been shown to be useful for reducing B1+ inhomogeneity using multiple transmitters due to their ability to spatially shape the slice profile. Recently, two‐dimensional spectral‐spatial pulses have been demonstrated to be effective for reducing the signal loss susceptibility artifact by incorporating a frequency‐dependent through‐plane phase correction. We present the use of four‐dimensional spectral‐spatial RF pulses for simultaneous B1+ and through‐plane signal loss susceptibility artifact compensation. The method is demonstrated with simulations and in T2*‐weighted human brain images at 3 T, using a four‐channel parallel transmission system. Parallel transmission was used to reduce the in‐plane excitation resolution to improve the slice‐selection resolution between two different pulse designs. Both pulses were observed to improve B1+ homogeneity and reduce the signal loss artifact in multiple slice locations and several human volunteers. Magn Reson Med 64:1–8, 2010. © 2010 Wiley‐Liss, Inc.
Image restoration and spatial resolution in 7‐tesla magnetic resonance imaging
Authors: Lohmann Gabriele , Bohn Stefan , Müller Karsten , Trampel Robert , Turner Robert
Published: June 2010

A good spatial resolution is essential for high precision segmentations of small structures in magnetic resonance images. However, any increase in the spatial resolution results in a decrease of the signal‐to‐noise ratio (SNR). In this article, this problem is addressed by a new image restoration technique that is used to partly compensate for the loss in SNR. Specifically, a two‐stage hybrid image restoration procedure is proposed where the first stage is a Wiener wavelet filter for an initial denoising. The artifacts that will inevitably be produced by this step are subsequently reduced using a recent variant of anisotropic diffusion. The method is applied to magnetic resonance imaging data acquired on a 7‐T magnetic resonance imaging scanner and compared with averaged multiple measurements of the same subject. It was found that the effect of image restoration procedure roughly corresponds to averaging across three repeated measurements. Magn Reson Med 64:15–22, 2010. © 2010 Wiley‐Liss, Inc.
Bank and corporation Taxes in Massachusetts
Authors: Long Henery F.
Published: June 2010

Under the present federal statute (Sec. 5219) authorizing the states to tax national banks, the states are given three optional methods of bank taxation. Under the second of these options, which MAssachusetts has chosen, a tax may be laid on the “net income” of national banks at the same rate assessed upon other financial corporations provided such rate shall not be higher than the highest of the rates assessed upon mercantile, manufacturing and business corporations. When this option is taken advantage of by a stae the question is raised, how shall net income be defined and what rate is to be applied The banks and the mercantile, manufacturing and busingess corporaions mut be treated alike so that there are many difficulties inteh way of legislative and tax authorities. The following statemnet by the Massachusetts commissioner of corporations and taxation throws a great deal of light oonthe decision which was reached at the recent session of the MAssachusetts General Court.
Cincinnati's comprehensive city plan
Authors: Fordd George B.
Published: June 2010

Cincinnati is the first city in the country to addopt officially a comprehensive city plan.
Public and private provision for social service in New York city
Authors: Bowman LeRoy E.
Published: June 2010

Another article in our series on division of responsibility for public welfare between public and private agencies.
State supervision of municipal finance in New Jersey
Authors: Kilpatrickl Wylie
Published: June 2010

State supervision, not accomplished without opposition from “home‐rules,” has followed a temperate policy guided by intelligennt under‐standing with gratifying success.
Volatile compounds with characteristic odour in moso‐bamboo stems (Phyllostachys pubescens Mazel ex Houz. De ehaie)
Authors: Takahashi Toshiyuki , Mizui Kohji , Miyazawa Mitsuo
Published: June 2010

Introduction – Moso‐bamboo (Phyllostachys pubescens) is well known as an edible shoot in Asia, and the stems of moso‐bamboo are used as tableware due to its characteristic odour. Despite the pleasant odour of bamboo stems, no detailed analysis of the volatile compounds has been reported.

Objective – To clarify the potent odourants contributing to the characteristic aroma of the bamboo, the aroma extract dilution analysis (AEDA) method was performed through gas chromatography olfactometry (GC‐O) analysis. In addition, relative flavour activity (RFA) was calculated, in which both the flavor dilution (FD) factor and weight percentage of each compound are involved.

Results – Eighty‐nine compound in bamboo stems oil were identified by GC and GC‐MS. The main components of the oil were palmitic acid (16.5%), (E)‐nerolidol (10.2%) and indole (8.1%). In sensory analysis, 18 aroma‐active compounds were detected by aroma extract dilution analysis (AEDA). The most intense aroma‐active compounds were eugenol (sweet, clove‐like, green) and (E)‐2‐nonenal (green).

Conclusion – The results of the sniffing test, RFA and FD factor indicated that (E)‐2‐nonenal and eugenol were estimated to have a bamboo‐like aroma, and aldehyde compounds, such as a phenylacetaldehyde (floral) and C9–C10 unsaturated aldehydes, make the aroma of bamboo. Copyright © 2010 John Wiley & Sons, Ltd.
Isolation of two bioactive diterpenic acids from Copaifera glycycarpa oleoresin by high‐speed counter‐current chromatography
Authors: De Souza P. A. , Rangel L. P. , Oigman S. S. , Elias M. M. , Ferreira‐Pereira A. , De Lucas N. C. , Leitão G. G.
Published: June 2010

Introduction – Phytochemical and biological studies carried out on Copaifera species showed that their oleoresins and isolated compounds have various biological activities.

Objective – The aims of this work were (i) to analyse the Copaifera oleoresin by gas chromatography–mass spectrometry, (ii) to isolate the diterpenic acids from this oleoresin by high‐speed countercurrent chromatography (HSCCC) and (iii) to determine the rhodamine 6G Pdr5p activity of these acids.

Methodology – HSCCC was used for the preparative separation of the diterpenes. Spectroscopic methods were used to establish their identity.

Results – The gas chromatogram of the oleoresin showed approximately 30 compounds. The two major ones, kaur‐16‐en‐18‐oic and polyalthic acids, were isolated in high purity. Kaur‐16‐en‐18‐oic acid exhibited the highest rodomine 6G Pdr5p activity among the tested compounds.

Conclusion – HSCCC was shown to be a quick and effective tool in the isolation and purification of diterpenes from Copaifera oleoresin. This is the first report on the use of HSCCC for the fractionation of an oleoresin from Copaifera and the isolation of diterpenes therein. Copyright © 2010 John Wiley & Sons, Ltd.
Down syndrome screening using first‐trimester combined tests and contingent use of femur length at routine anomaly scan
Authors: Salomon Laurent J. , Chevret Sylvie , Bussieres Laurence , Ville Yves , Rozenberg Patrick
Published: June 2010

Objective

The objective of this study was to evaluate the performance of the contingent use of femur length (FL) at routine mid‐trimester scan in screening for Down syndrome (DS) in women having previously undergone first‐trimester screening with disclosure of risk estimates.

Methods

Data from a prospective screening trial for DS in a population of 21 492 women with 80 observed DS were used. The performance of a contingent screening strategy based on adding short FL (FL < 5th percentile) as a soft marker in women at intermediate first‐trimester risks was evaluated through simulated data.

Results

In our population, the median (25th–75th percentile) maternal age was 30.7 years (28.0–33.9; range: 18.0–46.3). The median (25th–75th percentile) gestational age at ultrasound examination was 12 weeks 3 days (12 weeks and 12 weeks 6 days; range: 11 weeks to 13 weeks 6 days). Contingent screening allowed an improvement in screening performance. For example, using a first‐trimester risk cut‐off of 1/100 and an intermediate‐risk population within (1/1000, 1/100) for the search of FL, a sensitivity (Se) of 88.4% at a 3% false‐positive rate (FPR) was reached. With a cut‐off of 1/200 and an intermediate‐risk population within (1/1000, 1/200), screening would allow an Se of 92.3% at a 4% FPR.

Conclusions

Contingent screening could be used following first‐trimester combined screening followed by second‐trimester ultrasound soft markers. This could identify indications for early invasive testing in the highest risk cases and would allow efficient and simple ultrasound‐based screening in the second trimester. This would provide an 88.4% Se for a 3% FPR, at no additional cost as compared to first‐trimester combined screening and routine mid‐trimester scan. Copyright © 2010 John Wiley & Sons, Ltd.