bluuebunny/crossref_metadata_2025_split huggingface dataset:
Correlative MR imaging and histopathology in porcine neurocysticercosis
Authors: Chawla Sanjeev , Husain Nuzhat , Kumar Sunil , Pal Lily , Tripathi Mukesh , Gupta Rakesh K. 
Published: July 2004

AbstractPurposeTo examine whether all the histopathologically seen features of cysticercus cysts excised from brain of swine naturally infected with neurocysticercosis during its evolution are actually visible on magnetic resonance imaging (MRI).Materials and MethodsFive swine naturally infected with cerebral cysticercosis were subjected to fast spin‐echo (SE) T2, SE T1, fluid attenuated inversion recovery imaging, T1‐weighted magnetization transfer (MT), and postcontrast T1‐weighted MT sequences on MRI. These animals were sacrificed after imaging and ex vivo imaging of the intact excised brain using the same imaging protocol was also performed. Grossing of these brains was done similar to the ex vivo imaging planes. Numeral density and external appearance of each cyst and scolex were evaluated on each pulse sequence. Amount of pericystic edema, if present, was also assessed. On histopathology, cellular characteristics, inflammatory response, and the extent of edema, if present, in the brain parenchyma around the cysts were graded. Cysts were categorized into viable, early, and late degenerated on histopathology. The MRI features of each cyst were correlated with their histopathologic findings.ResultsOut of 31 cysts, eight were found to be viable, 13 early degenerated, and 10 late degenerated on histopathology. T2‐weighted imaging demonstrated all the cysts while T1‐weighted imaging showed 97% of the cysts. Scolex was seen in 90.3% and 93.5% of the cysts on T2‐ and T1‐weighted images, respectively. Minimal edema (grade I) and inflammation in degenerating cysts present on histopathology was not visible on MRI. All but one of eight degenerated cysts, which showed enhancement on postcontrast MRI, had edema on imaging as well as on histopathology.ConclusionT2‐weighted MRI demonstrated all the cysts that were visible on histopathology. Non‐enhancement of some of the degenerated cysts along with absence of edema on MRI is likely to underestimate the staging of neurocysticercosis evolution, and these early degenerating cysts may be misdiagnosed as in viable stage. J. Magn. Reson. Imaging 2004;20:208–215. © 2004 Wiley‐Liss, Inc.
Single‐shot half‐fourier RARE sequence with ultra‐short inter‐echo spacing for lung imaging
Authors: Ohno Yoshiharu , Oshio Koichi , Uematsu Hidemasa , Nakatsu Masashi , Gefter Warren B. , Hatabu Hiroto 
Published: July 2004

AbstractPurposeTo improve the image quality of pulmonary magnetic resonance (MR) imaging using an ultra‐short inter‐echo spacing half‐Fourier single shot rapid acquisition with relaxation enhancement (USHA‐RARE) sequence.Materials and MethodsPulmonary MR images were acquired by USHA‐RARE sequence with various inter‐echo spacings. The sequence parameters were as follows: repetition time (TR)/effective TE: infinite/39–41 msec; section thickness: 10 mm; acquisition matrix: 128 × 128; field of view: 450 × 450 mm. Inter‐echo spacing varied (2.5 msec, 3.0 msec, 3.5 msec, 4.0 msec, 4.5 msec, 5.0 msec), and the respective phase‐encoding steps were 80, 77, 75, 74, 73, and 72. Signal‐to‐noise ratios (SNRs), the signal ratios between lung and fat (lung‐to‐fat ratio: LFRs), and the signal ratios between the lung and the serratus anterior muscle (lung‐to‐muscle ratio: LMRs) of each inter‐echo spacing were calculated, and statistically evaluated.ResultsThe SNRs at inter‐echo spacings of ≤ 3.0 msec were significantly higher than those ≥ 4.0 msec (P < 0.05). The LFRs and LMRs at inter‐echo spacing ≤ 3.0 msec were significantly higher than those ≥ 4.0 msec (P < 0.05).ConclusionUSHA‐RARE sequence does improve signal intensity from the lung. J. Magn. Reson. Imaging 2004;20:336–339. © 2004 Wiley‐Liss, Inc.
Statistics‐based approach for aneurysm volume measurements
Authors: Vemuri Prashanthi , Kholmovski Eugene G. , Goodrich K. Craig , Zhang Ling , Tsuruda Jay S. , Parker Dennis L. 
Published: July 2004

AbstractPurposeTo evaluate the ability of high‐resolution MRA to monitor changes in intracranial aneurysm volume, and devise a highly reliable technique for obtaining these measurements.Materials and MethodsTo obtain a baseline estimate of the repeatability of MRA scans and validate the statistics‐based technique for aneurysm volume measurement, multiple scans were obtained on individual subjects over a period of up to 1 year. These 3D MRA data sets were coregistered and then analyzed using the volumetric analysis of segmented data and the proposed statistical method.ResultsIt was shown that high‐resolution MRA provides highly repeatable data sets. Both methods used for the aneurysm volume measurements showed consistent results. However, the proposed statistical method had lower error and was much less sensitive to the choice of segmentation parameter than the volumetric analysis of segmented data. A change of 1 mm in the average radius of the aneurysm was detectable with the statistics‐based technique.ConclusionsThis study demonstrates that the statistical method of aneurysm volume measurement in high‐resolution MRA allows reliable and accurate assessments of aneurysm volume changes. J. Magn. Reson. Imaging 2004;20:340–346. © 2004 Wiley‐Liss, Inc.
Relationship of apparent myocardial T2 and oxygenation: Towards quantification of myocardial oxygen extraction fraction
Authors: Zheng Jie , Wang Jinghua , Rowold Faith E. , Gropler Robert J. , Woodard Pamela K. 
Published: July 2004

AbstractPurposeTo explore the relationship of myocardial T2 and oxygenation for the quantification of myocardial oxygen extraction fraction (OEF).Materials and MethodsA proposed myocardial T2‐OEF relationship was evaluated by computer simulation and in nine normal dogs in vivo. The relationship was based on a simplified two‐compartment T2 model. In the dogs, dipyridamole was infused intravenously to increase blood flow and change in myocardial oxygen content. The accuracy of the measurement in myocardial OEF in vivo by magnetic resonance imaging (MRI) was determined by arterial and coronary sinus blood sampling.ResultsGlobal myocardial T2 increased 16.1% from rest to the peak of dipyridamole‐induced vasodilation (44.6 ± 2.1 msec vs. 51.4 ± 2.1 msec, P < 0.001). Corresponding OEF measured by arterial and venous (AV) sampling decreased from 0.64 ± 0.15 at rest to 0.18 ± 0.08 during the dipyridamole vasodilation, whereas OEF calculated by MRI at the peak effect of dipyridamole was 20 ± 4%. Global myocardial OEF measured dynamically by MRI showed a strong correlation with OEF measured by blood sampling (correlation coefficient (CC) = 0.83) during pharmacologic vasodilation.ConclusionWhen combined with vasodilator stress, assessment of OEF may provide a putative measure of myocardial flow reserve, allowing consecutive monitoring of myocardial dose‐responses to a variety of interventions and offering a new tool for the detection of coronary artery disease. J. Magn. Reson. Imaging 2004;20:233–241. © 2004 Wiley‐Liss, Inc.
Tumor enhancement using Mn‐metalloporphyrin in mice: Magnetic resonance imaging and histopathologic correlation
Authors: Nasu Hatsuko , Takehara Yasuo , Isogai Satoshi , Kodaira Nami , Takeda Hiroyasu , Saga Tsuneo , Nakajima Susumu , Sakata Isao , Sakahara Harumi 
Published: July 2004

AbstractPurposeTo determine the signal enhancement characteristics of tumors after administration of a metalloporphyrin derivative, HOP‐9P (13, 17‐bis (1‐carboxypropionyl) carbamoylethyl‐3, 8‐bis (1‐phenylpropyloxyethyl)‐2, 7, 12, 18‐tetramethyl‐porphyrinato manganese (III)) and to determine whether HOP‐9P is tumor‐necrosis specific.Materials and MethodsTen C3H/He mice bearing a SCC VII tumor in the right flank were examined using T1‐weighted conventional spin echo magnetic resonance (MR) imaging before contrast injection, and five minutes, one hour, and 24 hours after intravenous administration of 0.1 mmol/kg of HOP‐9P. Following the imaging schedule, the mice were sacrificed, and sectioned in the same axial planes as the MR images. Based on an MR imaging‐histopathologic correlation, mean signal intensities were measured, and signal‐to‐noise ratios (SNR) were calculated for both pure viable component and admixture of necrotic and viable component of the tumor.ResultsMean SNR of the pure viable component peaked at one hour (35.0 ± 3.8) and maintained that level until 24 hours (34.6 ± 3.6). Mean SNR of the admixture of necrotic and viable component peaked at 24 hours (44.3 ± 12.1).ConclusionAlthough different enhancement patterns were seen between the pure viable component and the admixture of necrotic and viable component, HOP‐9P enhanced both of the two components. J. Magn. Reson. Imaging 2004;20:294–299. © 2004 Wiley‐Liss, Inc.
Contrast‐enhanced magnetic resonance cholangiography using mangafodipir compared with standard T2W MRC sequences: A pictorial essay
Authors: Sheppard Declan , Allan Lynsay , Martin Pat , McLeay Trudy , Milne Wendy , Houston J. Graeme 
Published: July 2004

AbstractMangafodipir, a manganese‐containing hepatobiliary contrast agent, is excreted in bile. We review the principles and practice of a contrast‐enhanced MRC technique using mangafodipir and compare it with standard T2‐weighted magnetic resonance cholangiography (MRC) sequences. Potential applications include the evaluation of leaks and strictures; the assessment of drainage in normal, surgically by‐passed, stented and obstructed biliary systems; the diagnosis of cholecystitis; and the evaluation of normal and variant biliary anatomy. J. Magn. Reson. Imaging 2004;20:256–263. © 2004 Wiley‐Liss, Inc.
Image construction methods for phased array magnetic resonance imaging
Authors: Erdogmus Deniz , Yan Rui , Larsson Erik G. , Principe Jose C. , Fitzsimmons Jeffrey R. 
Published: July 2004

AbstractPurposeTo study image construction in phased array magnetic resonance imaging (MRI) systems from a statistical signal processing point of view.Materials and MethodsThree new approaches for image combination with multiple coils are proposed: 1) one based on the singular value decomposition of the measurement matrix, which is asymptotically optimal in the signal‐to‐noise ratio sense; 2) one based on a maximum‐likelihood formulation, incorporating a priori information on the coil sensitivities in a Bayesian manner; and 3) one based on a least‐squares formulation, which incorporates a smoothness constraint on the coil sensitivities.ResultsNumerical examples using synthetic and real data are presented to illustrate the performance of these new approaches. Results on the synthetic data show improvement in signal‐to‐error ratio, while results on the real data (a 4.7 T four‐coil image of a cat spinal cord) show that the proposed methods can improve the SNR in the final image by up to 3 dB in the regions of interest compared to conventional sum‐of‐squares processing.ConclusionIt is demonstrated that phased array MRI reconstruction performance can be improved by the use of more elaborate statistical signal processing algorithms. J. Magn. Reson. Imaging 2004;20:306–314. © 2004 Wiley‐Liss, Inc.
A comparison of images generated from diffusion‐weighted and diffusion‐tensor imaging data in hyper‐acute stroke
Authors: Harris Ashley D. , Pereira Raoul S. , Mitchell J. Ross , Hill Michael D. , Sevick Robert J. , Frayne Richard 
Published: July 2004

AbstractPurposeTo compare isotropic (combined diffusion‐weighted image [CMB], apparent diffusion coefficient [ADC], TRACE, exponential ADC [eADC], and isotropically‐weighted diffusion image [isoDWI]) and anisotropic (relative anisotropy [RA], fractional anisotropy [FA], and volume ratio [VR]) diffusion images collected with fast magnetic resonance (MR) diffusion‐weighted (DWI) and diffusion‐tensor (DTI) acquisition strategies (each less than one minute) in hyper‐acute stroke.Materials and MethodsTwenty‐one patients suffering from ischemic stroke—imaged within six hours of symptom onset using both DWI and DTI—were analyzed. Regions of interest were placed in the ischemic lesion and in normal contralateral tissue and the percent difference in image intensity was calculated for all nine generated images.ResultsThe average absolute percent changes for the isotropic strategies were all > 38%, with isoDWI found to have a difference of 50.7% ± 7.9% (mean ± standard error, P < 0.001). The ADC maps had the most significant difference (–42.4% ± 2.0%, P < 0.001, coefficient of variation = 0.22). No anisotropic images had significant differences.ConclusionAnisotropic maps do not consistently show changes in the first six hours of ischemic stroke; therefore, isotropic maps, such as those obtained using DWI, are more appropriate for detecting hyper‐acute stroke. Anisotropic images, however, may be useful to differentiate hyper‐acute stroke from acute and sub‐acute stroke. J. Magn. Reson. Imaging 2004;20:193–200. © 2004 Wiley‐Liss, Inc.
6‐hydroxydopamine induces dopaminergic cell degeneration via a caspase‐9‐mediated apoptotic pathway that is attenuated by caspase‐9dn expression
Authors: Liang Qinghua , Liou Anthony K.F. , Ding Yunmin , Cao Guodong , Xiao Xiao , Perez Ruth G. , Chen Jun 
Published: July 2004

AbstractThis study showed that primary dopaminergic neurons or the dopaminergic cell line MN9D, when exposed to 15 min of the parkinsonian toxin 6‐hydroxydopamine (6‐OHDA) in the range of 30–100 μM, underwent delayed degeneration and exhibited hallmarks of apoptosis. These results, along with the absence of any increase in lactate dehydrogenase (LDH) release from the degenerated cells, imply that apoptosis was the dominant mode of cell death. Moreover, a distinct elevation in the measured cellular activities of caspase‐9 and ‐3 but not of caspase‐8 points to the caspase‐9/caspase‐3 cascade as the predominant apoptotic pathway in the degeneration of dopaminergic neurons and MN9D cells. In addition, the presence of caspase‐9 or ‐3 peptide inhibitors but not of caspase‐8 inhibitor attenuated cell death significantly, supporting the notion that only the intrinsic apoptotic pathway is utilized to achieve cell death. Finally, overexpression of a mutant caspase‐9 with dominant negative phenotype (caspase‐9dn) in MN9D cells and primary dopaminergic neurons via the adenovirus and adenoassociated virus gene delivery system, respectively, conferred marked increases in tolerance to the toxicity of 6‐OHDA. These results point to the intrinsic caspase‐9/caspase‐3 cascade as the predominant signaling pathway underlying dopaminergic cell death induced by 6‐OHDA and suggest that gene delivery of caspase‐9dn can attenuate this pathway and its degenerative consequences. © 2004 Wiley‐Liss, Inc.
Lectin‐binding epitopes at the surface of Escherichia coli K‐12: examination by electron microscopy, with special reference to the presence of a colanic acid‐like polymer
Authors: Stoitsova Stoyanka , Ivanova Radka , Dimova Ivanka 
Published: July 2004

AbstractThe presence and distribution of lectin‐binding epitopes at the surface of Escherichia coli K‐12, strain W1655, was studied by electron microscopy after lectin‐gold labeling and negative staining. A comparison was made between the lectin‐binding capacity of cells cultivated at 20 °C and 37 °C (in broth or on agar). A variety of pre‐treatment protocols were applied prior to labeling. The gold‐conjugated lectins used were wheat germ agglutinin (WGA), soybean agglutinin (SBA) and Ulex europaeus lectin (UEA‐I). For all culture conditions, the bacteria had moderate exposure of WGA‐binding sites, and this was not changed after pre‐treatment. Cells cultivated at 37 °C had exposed SBA‐ and UEA‐I‐binding epitopes apparently associated with the cell surface. These significantly increased in number after boiling the cells for 10 min. With bacteria cultivated at 20 °C these two lectins recognized sites situated on exopolysaccharide filaments. Affino dot‐blot experiments with isolated polysaccharides of the strain identified the K‐12 lipooligosaccharide as the source of WGA‐binding epitopes, and the exopolysaccharide, colanic acid (CA) as the source of SBA‐ and UEA‐I‐binding sites. The interaction with these two lectins of bacteria cultivated at 37 °C could be due to altered translocation of CA from the cytoplasm to the environment. This suggestion was supported by the demonstration by electron microscopy of SBA and UEA‐I binding at the surface of hot phenol‐water extracted cell walls. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Lignoren, a new sesquiterpenoid metabolite from Trichoderma lignorum HKI 0257
Authors: Berg Albrecht , Kemami Wangun Hilaire V. , Nkengfack Augusin E. , Schlegel Brigitte 
Published: July 2004

AbstractThe new compound lignoren (1) was isolated from Trichoderma lignorum HKI 0257 by chromatographic methods. This metabolite has a santalane‐like structure, which was elucidated by mass spectrometric and NMR spectroscopic investigations. Lignoren (1) shows a moderate narrow‐spectrum of antibacterial and antifungal activity. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Isolation of Citrobacter sp. mutants defective in decolorizing malachite green
Authors: Jang Moon‐Sun , Lee Young‐Mi , Choi Yong‐Lark , Cho Young‐Su , Kim Cheorl‐Ho , Lee Young‐Choon 
Published: July 2004

AbstractTo identify genes involved in the decolorization of malachite green, random mutants generated by transposon insertion in the malachite green‐decolorizing bacterium, Citrobacter sp. were isolated. The resulting mutant bank yielded 24 mutants with complete defects in their abilities to decolorize malachite green. Southern hybridization with a Tn5 fragment as a probe showed a single hybridized band in 7 mutants, which appeared to have insertions at different sites of the chromosome. The Tn5‐inserted genes were isolated and the DNA sequence flanking Tn5 was determined. Based on a sequence database, the putative protein products encoded by the mg genes were identified as follows. mg3, an ABC transporter homolog; mg6, a LysR‐type regulatory protein; m11, an oxidoreductase; mg17, a MalG protein in the maltose transport system; and mg21, a sugar kinase. The deduced sequences from two mg genes (mg7 and mg18) showed no significant similarity to any protein with a known function, suggesting that these two mg genes encode unidentified proteins that are responsible for the decolorization of malachite green. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Entomopathogenic potential of Metarhizium anisopliae isolated from engorged females and tested in eggs and larvae of Boophilus microplus (Acari: Ixodidae)
Authors: Kamp Fernandes Éverton Kort , da Costa Gisela Lara , Lage de Moraes Aurea Maria , Pinheiro Bittencourt Vania Rita Elias 
Published: July 2004

AbstractThe purpose of this work was to evaluate the in vitro virulence of three isolates of Metarhizium anisopliae var. anisopliae to eggs and larvae of the tick Boophilus microplus. The fungus tested was isolated from engorged females of B. microplus collected in the field, and identified as Ma01, Ma02 e Ma04. These isolates were evaluated by immersion of eggs and larvae in suspension with different conidial concentrations: 105, 106, 107 e 108 conidia/ml. In each isolate there was a treatment group for each spore concentration and a control group with 10 repetitions. It was observed in the treated egg groups that there was a hatching percentage that was much less than that observed in the control groups. This was in inverse proportion to the conidia concentration/ml. Larval bioassays of all the tested isolates resulted in a high mortality of larvae in direct proportion to the spore concentration/ml, 10 days after the conidia suspensions were inoculated. To consolidate the infection, the fungus used in bioassays was re‐isolated. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Influence of growth conditions on the production of a bacteriocin by Lactococcus lactis subsp. lactis ST34BR, a strain isolated from barley beer
Authors: Todorov Svetoslav D. , Dicks Leon M. T. 
Published: July 2004

AbstractBacteriocin ST34BR, a small polypeptide of 2.9 kDa produced by Lactococcus lactis subsp. lactis ST34BR, inhibits the growth of Enterococcus faecalis, Escherichia coli, Lactobacillus plantarum, Lactobacillus casei, Pseudomonas aeruginosa and Staphylococcus aureus. MRS broth, adjusted to pH 6.0 yielded 6,400 AU/ml, compared to 400 AU/ml recorded in BHI broth, M17 broth, 10% (w/v) soy milk, and 8% and 10% (w/v) molasses. At pH of 4.5 only 800 AU/ml was produced. Based on comparative studies in MRS broth, without organic nitrogen, supplemented with different combinations of tryptone, meat extract and yeast extract, tryptone was identified as the stimulating nitrogen compound. Growth in the presence of 20 g/l glucose, maltose, mannose or sucrose yielded bacteriocin levels of 6,400 AU/ml, whereas the same concentration of lactose and fructose yielded 3,200 AU/ml and 1,600 AU/ml, respectively. No difference in bacteriocin ST34BR activity was recorded in MRS broth supplemented with 2 g/l K2HPO4 and 2 g/l, 5 g/l, 10 g/l or 50 g/l KH2PO4. However, 20 g/l KH2PO4 increased bacteriocin ST34BR production to 12,800 AU/ml. Glycerol at 1g/l to 10 g/l in MRS broth reduced bacteriocin activity to 3,200 AU/ml, whilst 20 g/l and 50 g/l yielded only 1,600 AU/ml. The presence of cyanocobalamin, L‐ascorbic acid, thiamine and dl‐6,8‐thioctic acid in MRS broth at 1.0 ppm, respectively, did not result in increased activity levels. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Use of antibiotics at hospitals in Stockholm: a benchmarking project using internet
Authors: Bergman Ulf , Risinggård Helena , Vlahović‐Palčevski Vera , Ericsson Örjan 
Published: July 2004

AbstractPurposeTo evaluate the internet way of feedback to prescribing physicians, providing data on antimicrobial use and to assess the applicability of the DU90% (i.e. Drug Utilisation 90%—the number of drugs accounting for 90% of the volume of usage in defined daily doses, (DDDs)) methodology in the hospital setting.MethodsAntimicrobial drug use was evaluated in all major departments in seven hospitals in Stockholm in the year 2000. All data were presented anonymously on www.janusinfo.org. Aggregate data on antimicrobial drug use were expressed as the number of DDDs and costs per 100 bed‐days. We focused on the number of drugs accounting for 90% of the volume (DDD), including the level of adherence to guidelines. The chief physicians assessed this feedback by a questionnaire.ResultsThe number of DDDs/100 bed‐days varied among different clinics and ranged from 39 to 57 (internal medicine) to 102 to 161 (infectious disease). The cost per 100 bed‐days varied more than two‐fold. The number of different antibiotics within the DU90% segment ranged from 9 to 13 (orthopaedic clinics) to 16 to 23 (infectious disease). According to the questionnaire, data were considered to be clearly presented and physicians would like to receive this kind of reports in the future, not only for antibiotics but also for other drugs.ConclusionPresenting physicians with aggregate data on drug use via internet could provide a stimulus for prescribing improvement. Copyright © 2003 John Wiley & Sons, Ltd.