bluuebunny/crossref_metadata_2025 huggingface dataset:
Sperm storage and motility in the ovary of the marine sculpin Alcichthys alcicornis (Teleostei: Scorpaeniformes), with internal gametic association
Authors: Koya Yasunori , Munehara Hiroyuki , Takano Kazunori
Published: August 2002

Elkhorn sculpin, Alcichthys alcicornis, is a marine teleost with a unique reproductive mode called “internal gametic association,” in which sperm introduced into the ovary by copulation enter the micropylar canal of ovulated eggs in the ovarian cavity, but actual sperm‐egg fusion does not occur until the eggs have been released into sea water. It is also known that this fish is a multiple spawner, which spawns at intervals of a few days for one month, and the sperm introduced into the ovary at the beginning of the spawning season retain their fertilizability for the entire period. To clarify how the fertilizability of sperm is maintained internally, the ultrastructure of sperm, the morphological characteristics related to sperm storage in the ovary, and the characteristics of sperm motility were investigated. Mature sperm generally have the normal form of teleost sperm, devoid of acrosomal structures. However, it was found that the midpiece is comparatively elongated and has a compact aggregation of many small‐size mitochondria. The intraovarian sperm remained floating in the ovarian fluid throughout the spawning season. The sperm showed high motility in isotonic and weak alkaline solution, containing sodium ions, which was similar to the ovarian fluid of this fish. Sperm continued to move in artificial ovarian fluid for 7–14 days. Considering these results together, it is thought that the intraovarian sperm move throughout the spawning season due to the plentiful energy generated by the many mitochondria. J. Exp. Zool. 292:145–155, 2002. © 2002 Wiley‐Liss, Inc.
Function of the mammalian oviductal sperm reservoir
Authors: Töpfer‐Petersen Edda , Wagner Andrea , Friedrich Julia , Petrunkina Anna , Ekhlasi‐Hundrieser Mahnaz , Waberski Dagmar , Drommer Wolfgang
Published: August 2002

Sperm are stored in the isthmic region of the oviduct under conditions that maintain sperm viability and suppress motility. This region is also the site in which essential steps of the capacitation process are coordinated with the appearance of the ovulated egg. The influx of Ca2+ and phosphorylation of sperm proteins are features of the ongoing capacitation process. Using a cell‐culture system of oviductal epithelial cells, it was found that sperm bound to the epithelial cells showed a reduced Ca2+ uptake and almost no tyrosine phosphorylation as shown by indirect immunofluorescence. Furthermore, sperm viability, measured as membrane integrity with propidium iodide, is significantly prolonged as compared to sperm in suspension. The formation of the sperm reservoir appears to be mediated by carbohydrate‐protein interaction. In the pig, it has been found that mannosyl‐oligosaccharides exposed by the epithelial cells are high‐affinity ligands for sperm‐associated lectins. Ovalbumin and mannopentaose are effective inhibitors of sperm binding to explants of oviductal epithelium. Spermadhesins, a new class of animal lectins and the major secretory products of the porcine seminal vesicle, associate with the sperm surface at ejaculation and are candidate molecules for the receptors of the epithelial carbohydrates. J. Exp. Zool. 292:210–215, 2002. © 2002 Wiley‐Liss, Inc.
Lipovitellins derived from two forms of vitellogenin are differentially processed during oocyte maturation in haddock (Melanogrammus aeglefinus)
Authors: Reith Michael , Munholland Janet , Kelly John , Finn Roderick Nigel , Fyhn Hans Jørgen
Published: August 2002

In the process of cloning vitellogenin (Vtg) cDNAs from haddock (Melanogrammus aeglefinus), two related, but distinct, mRNAs were identified. Full‐length cDNA sequences were determined for both Vtg types (Had1 and Had2), and the deduced amino acid sequences were found to be 54% identical to each other and 48–58% identical to other teleost Vtgs. To investigate the expression of the two Vtg mRNAs, proteins from prehydrated oocytes and fertilized eggs were separated on SDS–polyacrylamide gels. Only a single lipovitellin I band was detected in each sample, and the egg lipovitellin I was smaller (97 vs. 110 kDa) than the oocyte protein, indicative of proteolytic processing during oocyte hydration. Mass spectrometric (MALDI‐TOFMS and tandem mass spectrometry) analyses of tryptic fragments from the haddock oocyte and egg lipovitellin I revealed that the lipovitellin I from prehydrated oocytes contained tryptic fragments that matched the sequences of both types of Vtg, suggesting that there were two proteins in this band, while the egg lipovitellin I contained tryptic fragments that only matched the Had1 cDNA sequence, indicating that the Had2 lipovitellin had been degraded during hydration. Physiological data from haddock oocytes and eggs demonstrate that, as in other marine fish that spawn pelagic eggs, the free amino acid content increases during oocyte hydration and apparently contributes to hydration by driving the osmotic uptake of water. The correlation of the disappearance of one lipovitellin I with the increase of free amino acids in the oocyte suggests that this protein is a major source of the free amino acids for oocyte hydration. J. Exp. Zool. (Mol. Dev. Evol.) 291:58–67, 2001. © 2001 Wiley‐Liss, Inc.
Polyethyleneimine‐based immunopolyplex for targeted gene transfer in human lymphoma celllines
Authors: Guillem Vicent M. , Tormo Mar , Revert Fernando , Benet Isabel , García‐Conde Javier , Crespo Antonio , Aliño Salvador F.
Published: August 2002

Background

Specific and efficient delivery of genes into targeted cells is a priority objective in non‐viral gene therapy. Polyethyleneimine‐based polyplexes have been reported to be good non‐viral transfection reagents. However, polyplex‐mediated DNA delivery occurs through a non‐specific mechanism. This article reports the construction of an immunopolyplex, a targeted non‐viral vector based on a polyplex backbone, and its application in gene transfer over human lymphoma cell lines.

Methods

Targeting elements (biotin‐labeled antibodies), which should recognize a specific element of the target cell membrane and promote nucleic acid entry into the cell, were attached to the polyplex backbone through a bridge protein (streptavidin). Immunopolyplex transfection activity was studied in several hematological cell lines [Jurkat (CD3+/CD19−), Granta 519 (CD3−/ CD19+), and J.RT3‐T3.5 (CD3−/CD19−)] using the EGFP gene as a reporter gene and anti‐CD3 and anti‐CD19 antibodies as targeting elements. Transfection activity was evaluated via green fluorescence per cell and the percentage of positive cells determined by flow cytometry.

Results

A significant selectivity of gene delivery was observed, since the anti‐CD3 immunopolyplex worked only in Jurkat cells while the anti‐CD19 immunopolyplex worked only in the Granta cell line. Moreover, transfection of a CD3+/CD3− cell mixture with anti‐CD3 immunopolyplexes showed up to 16‐fold more transfection in CD3+ than in CD3− cells. Several non‐specific transfection reagents showed poor or no transfection activity.

Conclusion

It is concluded that immunopolyplex is a good non‐viral vector for specific and selective nucleic acid delivery. Immunopolyplex design allows easy replacement of the targeting element (antibody) – the streptavidin–polyplex backbone remaining intact – thereby conferring high versatility. Copyright © 2002 John Wiley & Sons, Ltd.
Negotiating illness: Doctors, patients, and families in the nineteenth century
Authors: Theriot Nancy M.
Published: August 2002

This article is based on medical literature published in American and British monographs and medical journals in which physician‐authors utilized case histories of women's nervous and mental disease and related gynecological complaints. I argue that the interaction of physicians, patients, and families was a relationship in which women patients contributed to the formation of medical knowledge and forged a modern sense of body and self. After an introductory section on reading case studies, I call attention to the ways in which physicians, patients, and patients' families educated each other about wellness and illness, which formed the basis of physicians' interpretation of disease. Next, I point out how the case histories structured an ideal script for doctor, patient, and family, based on physicians' sympathetic authority and patients' willingness to tell and show all. And finally, I suggest that the doctor–patient dialogue encouraged women patients to see themselves as medically manageable bodies and as individuals separate from families. © 2001 John Wiley & Sons, Inc.
The World Development Report 2000/01: HIV/AIDS still not properly considered!
Authors: Barnett Tony , Whiteside Alan
Published: August 2002

The consequences of the evolving HIV/AIDS epidemic have not been properly considered by any agency. Most existing development indicators do not pick up the impact of AIDS nor do they measure the complex adverse consequences the disease may have in the decades ahead. Incomplete and conflicting demographic and health indicators compound the problem. This epidemic is a ‘long wave’ event and its effects will be seen in Africa and elsewhere for many decades ahead. The result is that development targets may be unattainable and the way development is carried out may need to be rethought in many countries. Copyright © 2001 John Wiley & Sons, Ltd.
Consumer preferences and the uptake of animal healthcare by the poor: a case study from Kenya
Authors: Heffernan Claire
Published: August 2002

This paper examines issues in the delivery of veterinary services to the poor in Kenya. Utilising a simplified livelihood approach, the study found that livestock most often functioned as a means of gaining social approbation rather than a risk mitigation strategy. In regard to the delivery of veterinary services, three key parameters were evaluated: access, acceptability and affordability. The assessment revealed that access to veterinary services rather than affordability is the primary constraint. However, few herders and farmers were spending close to the estimated ‘ideal’ on livestock drugs. Knowledge regarding livestock health was poor, further contributing to the overall low uptake of veterinary goods and services. Copyright © 2001 John Wiley & Sons, Ltd.
Getting online: Australian international development agencies and ICT use
Authors: Kiraka Ruth N. , Manning Karen
Published: August 2002

The paper discusses a study on the use of information and communication technologies (ICTs) by Australian international development agencies. ICT use was considered in two contexts—within industrialized countries, and between industrialized and developing countries (DCs). In these contexts, the use of ICTs at operational and strategic levels was examined. Findings show that ICT use was most common at operational levels within industrialized countries. ICT use in DCs was complicated by poor infrastructure and technology—culture conflicts. Copyright © 2002 John Wiley & Sons, Ltd.
The phantom of liberty?: economic growth and the vulnerability of small states
Authors: Armstrong Harvey W. , Read Robert
Published: August 2002

This paper is concerned with the relationship between economic growth in small states and their vulnerability. A critical argument in much of the literature on small states, particularly small island states, is that their growth performance is greatly constrained by their vulnerability to exogenous shocks because of their size. These shocks include economic, political and environmental factors, which together dampen the long‐run growth rate of these economies. The paper makes use of a global small state data set and appropriate quantitative techniques to test the relationship between growth and vulnerability using the results of Briguglio's Vulnerability Index. The results highlight some of the conceptual shortcomings in the analytical literature on small states, particularly islands, as well as suggesting that the Vulnerability Index is mis‐specified. Copyright © 2002 John Wiley & Sons, Ltd.
Studying group dynamics: an alternative analytical framework for the study of microfinance impacts on poverty reduction
Authors: Marr Ana
Published: August 2002

Group dynamics have been largely neglected when the impacts of microfinance on poverty reduction are assessed. This paper presents an analytical framework in which the study of group dynamics is central, and new channels of impact effects on the individuals participating in microfinance schemes, their households, enterprises and communities are assessed. Four potential outcomes of this fresh approach to the analysis of poverty impacts are argued; they may have dramatic implications for the way we look at the effectiveness of microfinance today. Copyright © 2002 John Wiley & Sons, Ltd.
Synthesis of deuterated 2‐amino‐1‐methyl‐6‐phenyl‐1H‐imidazo[4,5‐b]pyridine (PhIP) and its N‐hydroxy derivative
Authors: Tanga Mary J. , Bupp James E. , Bradford Wallace W.
Published: August 2002

The syntheses of the deuterium‐labeled food mutagen 2‐amino‐1‐methyl‐6‐phenyl‐1H‐imidazo[4,5‐b]pyridine (PhIP) and its N‐hydroxy metabolite are described. Unlabeled PhIP is deuterated using a boron trifluoride phosphoric acid complex in one step. Labeled PhIP–2H5 is nitrosated to give nitro‐PhIP, which is then reduced to N‐hydroxy–PhIP–2H5. Copyright © 2001 John Wiley & Sons, Ltd.
Fluorine‐18 labeling of peptide nucleic acids
Authors: Kuhnast Bertrand , Dolle Frédéric , Tavitian Bertrand
Published: August 2002

Peptide nucleic acids (PNAs) are a unique class of synthetic macromolecules, originally designed as ligands for the recognition of double stranded DNA. From a chemical point of view, the deoxyribose phosphate backbone of DNA is replaced by a pseudo‐peptide N‐(2‐aminoethyl)glycyl backbone, while the nucleobases of DNA (adenine, guanine, cytosine and thymine) are retained. Due to the increasing interest in the labeling of peptide nucleic acids (PNAs) as potent diagnostic agents in nuclear medicine, we have used and adapted the reliable methodology developed for the fluorine‐18 labeling of oligonucleotides and have now demonstrated that it is possible to label PNAs in sufficient quantity and with high specific radioactivity for PET studies in a time compatible with the half life of fluorine‐18. Copyright © 2002 John Wiley & Sons, Ltd.
Synthesis, labelling and biological characteristics of derivatives of Mercaptoacetyltriglycine with two amide functions
Authors: Okarvi S. M. , Verbeke K. , Adriaens P. , Verbruggen A. M.
Published: August 2002

Eight novel derivatives of MAG3, containing in their structure two instead of three amide functions, have been synthesized and evaluated. The synthesized ligands were labelled with 99mTc by exchange labelling at 100°C and/or by a direct labelling method at room temperature. After labelling with 99mTc, the reaction mixtures were analyzed by radio‐HPLC. Biological evaluation of different 99mTc‐diamide complexes in mice and a baboon indicated that substitution in one amide function of MAG3 structure greatly influences the renal handling of these compounds. It was found that the diamide derivatives containing at least one inverted amide exhibit biological behavior comparable to that of 99mTc‐MAG3. Copyright © 2002 John Wiley & Sons, Ltd.
Embryogenesis of the dipluranLepidocampa weberiOudemans (Hexapoda: Diplura, Campodeidae): Formation of dorsal organ and related phenomena
Authors: Ikeda Yatsukaho , Machida Ryuichiro
Published: August 2002

The developmental changes of embryonic membranes of a dipluranLepidocampa weberi, with special reference to dorsal organ formation, are described in detail by light, scanning, and transmission electron microscopies. Newly differentiated germ band and serosa secrete the blastodermic cuticle at the entire egg surface beneath the chorion. Soon after, the serosal cells start to move dorsad. All the serosal cells finally concentrate at the dorsal side of the egg and form the dorsal organ. During their concentration, the serosal cells attenuate their cytoplasm to form filaments. The extensive area from which the serosa has receded is occupied by a second embryonic membrane, the amnion, which originates from the embryonic margin. The embryo and newly emerged amnion then secrete three fine cuticular layers, “cuticular lamellae I, II, and III,” above which the filaments of the (developing) dorsal organ are situated. With the progression of definitive dorsal closure, the amnion reduces its extension, the dorsal organ is incorporated into the body cavity of the embryo, and the amnion and dorsal organ finally degenerate.The dorsal organ of diplurans is formed by the concentration of whole serosal cells, while that of collembolans is formed by the direct differentiation of a part of serosal cells. However, the dorsal organs of diplurans and collembolans closely resemble each other in major aspects, including that of ultrastructural features, and there is no doubt regarding their homology. The amnion, which has been regarded as being a characteristic of Ectognatha, also develops in the Diplura. This might suggest a closer affinity between the Diplura and Ectognatha than previously believed. J. Morphol. 249:242–251, 2001. © 2001 Wiley‐Liss, Inc.
Exquisite specificity and peptide epitope recognition promiscuity, properties shared by antibodies from sharks to humans
Authors: Marchalonis John J. , Adelman Miranda K. , Robey Ian F. , Schluter Samuel F. , Edmundson Allen B.
Published: August 2002

This review considers definitions of the specificity of antibodies including the development of recent concepts of recognition polyspecificity and epitope promiscuity. Using sets of homologous and unrelated peptides derived from the sequences of immunoglobulin and T cell receptor chains we offer operational definitions of cross‐reactivity by investigating correlations of either identities in amino acid sequence, or in hydrophobicity/hydrophilicity profiles with degree of binding in enzyme‐linked immunosorbent assays. Polyreactivity, or polyspecificity, are terms used to denote binding of a monoclonal antibody or purified antibody preparation to large complex molecules that are structurally unrelated, such as thyroglobulin and DNA. As a first approximation, there is a linear correlation between degree of sequence identity or hydrophobicity/hydrophilicity and antigenic cross‐binding. However, catastrophic interchanges of amino acids can occur where changing of one amino acid out of 16 in a synthetic peptide essentially eliminates binding to certain antibodies. An operational definition of epitope promiscuity for peptides is the case where two peptides show little or no identity in amino acid sequence but bind strongly to the same antibody as shown by either direct binding or competitive inhibition. Analysis of antibodies of humans and sharks, the two most divergent species in evolution to express antibodies and the combinatorial immune response, indicates that the capacity for both exquisite specificity and epitope recognition promiscuity are essential conserved features of individual vertebrate antibodies. Copyright © 2001 John Wiley & Sons, Ltd.
BIACORE J: a new platform for routine biomolecular interaction analysis†
Authors: Rich Rebecca L. , Myszka David G.
Published: August 2002

SPR biosensor technology continues to evolve. The recently released platform from Biacore AB (Uppsala, Sweden), BIACORE J, is designed for the routine analysis of biomolecular interactions. Using an antibody–protein A and a ligand–receptor system, we demonstrate the utility of BIACORE J in determining active concentration and binding affinities. The results from these studies illustrate the high sensitivity of the instrument and its ability to generate reproducible binding responses. The BIACORE J is easy to operate and useful in diverse applications, making SPR technology widely accessible as a research tool. Copyright © 2001 John Wiley & Sons, Ltd.
Dynamic contrast‐enhanced magnetic resonance imaging as a surrogate marker of tumor response to anti‐angiogenic therapy in a xenograft model of glioblastoma multiforme
Authors: Gossmann Axel , Helbich Thomas H. , Kuriyama Nagato , Ostrowitzki S. , Roberts Timothy P.L. , Shames David M. , van Bruggen N. , Wendland Michael F. , Israel Mark A. , Brasch Robert C.
Published: August 2002

Purpose

To evaluate the effects of a neutralizing anti‐vascular endothelial growth factor (anti‐VEGF) antibody on tumor microvascular permeability, a proposed indicator of angiogenesis, and tumor growth in a rodent malignant glioma model.

Materials and Methods

A dynamic contrast‐enhanced magnetic resonance imaging (MRI) technique, permitting noninvasive in vivo and in situ assessment of potential therapeutic effects, was used to measure tumor microvascular characteristics and volumes. U‐87, a cell line derived from a human glioblastoma multiforme, was implanted orthotopically into brains of athymic homozygous nude rats.

Results

Treatment with the monoclonal antibody A4.6.1, specific for VEGF, significantly inhibited tumor microvascular permeability (6.1 ± 3.6 mL min–1100 cc–1), compared to the control, saline‐treated tumors (28.6 ± 8.6 mL min–1100 cc–1), and significantly suppressed tumor growth (P < .05).

Conclusion

Findings demonstrate that tumor vascular permeability and tumor growth can be inhibited by neutralization of endogenous VEGF and suggest that angiogenesis with the maintenance of endothelial hyperpermeability requires the presence of VEGF within the tissue microenvironment. Changes in tumor vessel permeability and tumor volumes as measured by contrast‐enhanced MRI provide an assay that could prove useful for clinical monitoring of anti‐angiogenic therapies in brain tumors. J. Magn. Reson. Imaging 2002;15:233–240. © 2002 Wiley‐Liss, Inc.
Intracranial oscillations of cerebrospinal fluid and blood flows: Analysis with magnetic resonance imaging
Authors: Strik Claudia , Klose Uwe , Erb Michael , Strik Herwig , Grodd Wolfgang
Published: August 2002

Purpose

To detect oscillations of the cerebrospinal fluid (CSF) flow related to the heartbeat and frequencies lower than 0.6 Hz and to compare these oscillations of CSF and blood flow in cerebral vessels by using echo planar imaging in real time mode. The existence of such waves has been well known but has not yet been shown by MRI.

Materials and Methods

In a slice perpendicular to the aqueduct, CSF flow as well as CBF, could be determined in sagittal sinus, basilar artery, and capillary vessels. After Fourier analysis, four frequency bands were assigned.

Results

In the very high‐frequency (heart rate) range, the integrals under the CSF curves were more closely related to arterial CBF than to changes in the sinus. Also, in the high‐frequency (respiration rate), low‐frequency (0.05–0.15 Hz), and very‐low‐frequency (0.008–0.05 Hz) ranges, the integrals under the CSF curves corresponded with arterial and capillary CBF.

Conclusion

Slow and fast oscillations in CSF flow are detectable in healthy persons with a proportional allotment to arterial and capillary CBF. J. Magn. Reson. Imaging 2002;15:251–258. © 2002 Wiley‐Liss, Inc.
Simultaneously monitoring both T1 and T2* signal intensities on a bolus injection of Gd‐DTPA may distinguish infarcted myocardium
Authors: Mark John , Dai Guangping , Xiang Bo , Sun Jiankang , Lazarow Normand , Lindsay William G. , Corne Robert , Deslauriers Roxanne , Tian Ganghong
Published: August 2002

Purpose:

To determine whether injured myocardium may be identified by simultaneously monitoring contrast‐induced T1 and T2* signal intensity time‐course changes with an interleaved T1‐T2* imaging sequence.

Materials and Methods:

Gadolinium‐diethylene triamine pentaacetic acid (0.05 mmol/ kg) was injected as a bolus into ex vivo pig hearts, and simultaneous T1 and T2* time‐courses were obtained during the first pass.

Results:

Observing contrast‐enhanced R1 or R2* rates (1/T1 or 1/T2* times, respectively) early after contrast injection did not fully differentiate viable from nonviable myocardium. T2* recovery at maximal T1 signal intensity, measured using simultaneous T1 and T2* imaging, displayed a significantly different percentage recovery (P < 0.05) among normal (30.5 ± 2.4% of baseline value), reperfused infarcted (63 ± 7.2%), and low‐reflow infarcted (90 ± 2.8%) myocardium.

Conclusion:

Simultaneously monitoring both T1 and T2* signal intensities may help in the assessment of myocardial injury. J. Magn. Reson. Imaging 2002;15:532–540. © 2002 Wiley‐Liss, Inc.
Chronic hepatitis: Correlation of early patchy and late linear enhancement patterns on gadolinium‐enhanced MR images with histopathology initial experience
Authors: Semelka Richard C. , Chung Jae‐Joon , Hussain Shahid M. , Marcos Hani B. , Woosley John T.
Published: August 2002

The purposes of our study were to describe the early and late enhancement patterns of the liver on gadolinium‐enhanced dynamic magnetic resonance (MR) images in patients with chronic hepatitis and to correlate these findings with histopathology. Patients were entered into the study based on the presence of chronic hepatitis, imaging evaluation with MR imaging (MRI), including early and late postgadolinium images, and histopathologic correlation. Early and late dynamic postgadolinium MR images of 29 consecutive patients with a pathologically proven diagnosis of chronic hepatitis were retrospectively evaluated for the presence of three types of enhancement, i.e., homogeneous, linear, and patchy. Correlation was made between the enhancement patterns on MR images and blinded retrospective interpretation of the histopathologic specimens, which were obtained within 3 months of the MR examination. Of the 29 patients, 16 (55.2%) patients showed patchy enhancement on the early gadolinium‐enhanced MR images. In 11 (68.8%) of these 16 patients, histopathology demonstrated numerous macrophages, variable hepatocyte necrosis, and increased steatosis. The remaining 13 (44.8%) patients showed homogeneous enhancement on the early gadolinium‐enhanced MR images. In 11 (84.6%) of these 13 patients, histopathology demonstrated few or no macrophages, little or no hepatocellular necrosis, and little or no steatosis. The correlation between patchy enhancement and acute liver inflammation was significant (P= 0.005). On the late gadolinium‐enhanced MR images, 20 (69.0%) of 29 patients showed prominent linear enhancement. In 19 (95.0%) of these 20 patients, histopathology revealed hepatic fibrosis. We concluded that in patients with chronic hepatitis, the presence of early patchy enhancement indicates either concurrent or recent hepatocellular damage, whereas the presence of late linear enhancement indicates the presence of fibrosis, with a high degree of correlation with histopathologic findings. J. Magn. Reson. Imaging 2001;13:385–391. © 2001 Wiley‐Liss, Inc.
Proton magnetic resonance spectroscopic imaging reveals differences in spinocerebellar ataxia types 2 and 6
Authors: Boesch S.M. , Schocke M. , Bürk K. , Hollosi P. , Fornai F. , Aichner F.T. , Poewe W. , Felber S.
Published: August 2002

The objective of this study was to investigate cerebellar metabolism in patients with autosomal dominant cerebellar ataxia type 1 (ADCA‐I) carrying two distinct mutations of spinocerebellar ataxia (SCA). Non‐invasive image‐guided proton magnetic resonance spectroscopy imaging (1H‐MRSI) was performed in 4 patients with SCA2, and 3 patients carrying the SCA6 mutation. For MRSI, we employed a spin‐echo sequence (TR = 1500 msec, TE = 135 msec, slice thickness = 15 mm, FOV = 240 mm) and a stimulated‐echo sequence (TR = 1500 msec, TE = 20 msec, slice thickness = 15 mm, FOV = 240 mm). Measures included the peak integral ratios of neuronal and glial markers [N‐acetylaspartate (NA) to creatine (Cr), choline‐containing compounds (CHO) to Cr, and lactate (LAC) to Cr]. We found NA:Cr ratios were significantly lower in patients with SCA2 (40.4% lower) compared to patients carrying the SCA6 mutation. CHO:Cr ratios differed between the two mutations using short echo time (30.8% lower in SCA2), but not when applying long echo time 1H‐MRSI. Measurements using long echo time revealed LAC peaks in all SCA2 patients. 1H‐MRSI revealed metabolic differences between SCA2 and SCA6 patients. NA:Cr ratios were significantly lower in patients with the SCA2 mutation compared to the SCA6 mutation, and LAC signals were obtained in the cerebella of SCA2 patients. In addition, CHO:Cr ratios showed different behavior using short and long TE, indicating differences in relaxation times of choline compounds in SCA2. J. Magn. Reson. Imaging 2001;13:553–559. © 2001 Wiley‐Liss, Inc.
Relationship between bone marrow cellularity and apparent diffusion coefficient
Authors: Nonomura Yoshie , Yasumoto Mayumi , Yoshimura Ryoichi , Haraguchi Kyoko , Ito Sukeyuki , Akashi Takumi , Ohashi Isamu
Published: August 2002

This study was performed to determine if there is a relationship between apparent diffusion coefficient (ADC) and cellularity of bone marrow of the posterior ilium. Four groups of various marrow cellularity underwent diffusion‐weighted echo‐planar imaging: 1) adults with normal hypocellularity (21 patients); 2) adults with normal normocellularity (13 patients); 3) young children with normal hypercellularity (5 patients); and 4) adults with lymphoma‐related hypercellularity (3 patients). In all adults, marrow cellularity was confirmed by uni‐or bilateral bone marrow biopsies. In children, the iliac marrow was presumed hypercellular because of their ages. A total of 66 ADC values of bone marrow calculated from diffusion‐weighted images with b‐values of 30 and 300 seconds/mm2 was evaluated. Hypercellular marrow (normal and lymphoma‐related) showed the highest mean ADC, and hypocellular the lowest ADC. Statistically significant differences were found between three groups of normal marrow: hypocellular, normocellular, and hypercellular. There is a positive correlation between ADC and cellularity of bone marrow. J. Magn. Reson. Imaging 2001;13:757–760. © 2001 Wiley‐Liss, Inc.
Development, standardization, and testing of a lexicon for reporting contrast‐enhanced breast magnetic resonance imaging studies
Authors: Ikeda Debra M. , Hylton Nola M. , Kinkel Karen , Hochman Mary G. , Kuhl Christiane K. , Kaiser Werner A. , Weinreb Jeffrey C. , Smazal Stanley F. , Degani Hadassah , Viehweg Petra , Barclay John , Schnall Mitchell D.
Published: August 2002

The purpose of this study was to develop, standardize, and test reproducibility of a lexicon for reporting contrast‐enhanced breast magnetic resonance imaging (MRI) examinations. To standardize breast MRI lesion description and reporting, seven radiologists with extensive breast MRI experience developed consensus on technical detail, clinical history, and terminology reporting to describe kinetic and architectural features of lesions detected on contrast‐enhanced breast MR images. This lexicon adapted American College of Radiology Breast Imaging and Data Reporting System terminology for breast MRI reporting, including recommendations for reporting clinical history, technical parameters for breast MRI, descriptions for general breast composition, morphologic and kinetic characteristics of mass lesions or regions of abnormal enhancement, and overall impression and management recommendations. To test morphology reproducibility, seven radiologists assessed morphology characteristics of 85 contrast‐enhanced breast MRI studies. Data from each independent reader were used to compute weighted and unweighted kappa (κ) statistics for interobserver agreement among readers. The MR lexicon differentiates two lesion types, mass and non‐mass‐like enhancement based on morphology and geographical distribution, with descriptors of shape, margin, and internal enhancement. Lexicon testing showed substantial agreement for breast density (κ = 0.63) and moderate agreement for lesion type (κ = 0.57), mass margins (κ = 0.55), and mass shape (κ = 0.42). Agreement was fair for internal enhancement characteristics. Unweighted kappa statistics showed highest agreement for the terms dense in the breast composition category, mass in lesion type, spiculated and smooth in mass margins, irregular in mass shape, and both dark septations and rim enhancement for internal enhancement characteristics within a mass. The newly developed breast MR lexicon demonstrated moderate interobserver agreement. While breast density and lesion type appear reproducible, other terms require further refinement and testing to lead to a uniform standard language and reporting system for breast MRI. J. Magn. Reson. Imaging 2001;13:889–895. © 2001 Wiley‐Liss, Inc.
Line scan diffusion tensor MRI of the cervical spinal cord in preterm infants
Authors: Murphy Brendan P. , Zientara Gary P. , Huppi Petra S. , Maier Stephan E. , Barnes Patrick D. , Jolesz Ferenc A. , Volpe Joseph J.
Published: August 2002

Line scan diffusion tensor magenetic resonance imaging (DT‐MRI) of the cervical spinal cord was demonstrated in vivo for unsedated preterm (gestational age 24–30 weeks at birth), very low birthweight (birthweight 620–1300 g) infants at postmenstrual ages from 29–40 weeks. Scalar invariant measures of diffusion [apparent diffusion coefficient (ADC) and relative anisotropy (RA)] determined from a cervical cord region of interest in each case are reported, characterizing the maturational status of the normal third trimester and newborn spinal cord. Mean ADC of 11 infants was 1.2 ± 0.1 μm2/msec and the mean RA was 24.3 ± 4.9%. Normal infant cord neural fiber tract morphology was visualized using a mapping of the predominant diffusion tensor eigenvector. Potential clinical applications of line scan DT‐MRI of the spinal cord of preterm and term newborns for assessment of spinal cord injury are discussed. J. Magn. Reson. Imaging 2001;13:949–953. © 2001 Wiley‐Liss, Inc.
PROPELLER MRI: Clinical testing of a novel technique for quantification and compensation of head motion
Authors: Forbes Kirsten P.N. , Pipe James G. , Bird C. Roger , Heiserman Joseph E.
Published: August 2002

While head motion is considered a significant problem in magnetic resonance imaging (MRI), there is no data to quantify its extent, severity, or effect on image quality. PROPELLER (Periodically Rotated Overlapping ParallEL Lines with Enhanced Reconstruction) MRI offers a novel means of quantifying and compensating for head motion. We performed axial T2‐weighted PROPELLER (motion corrected: P‐CR; uncorrected: P‐UNCR) and conventional MRI (CONV), with equal scan times, in five normal volunteers and 35 clinical subjects. Volunteers were examined lying still and performing two separate head movements (shake “no” and nod “yes”) to assess detection and compensation of in‐plane motion by PROPELLER MRI. Images were examined by three radiologists for motion artifact and for overall image quality. Head rotation and translation was detected in all subjects during each slice acquisition, with expected changes occurring with volunteer head motion. Motion artifact was less commonly seen on PROPELLER than CONV MR (χ2 test P < 0.001). PROPELLER was preferred over CONV in all subjects (P < 0.05) and P‐CR was judged superior to P‐UNCR (P = 0.02). Intracranial pathology was equally or better demonstrated with PROPELLER. PROPELLER MRI offers a means of quantifying head motion, reducing motion artifact, and improving image quality. J. Magn. Reson. Imaging 2001;14:215–222. © 2001 Wiley‐Liss, Inc.
Evaluation of perianal sepsis: Comparison of anal endosonography and magnetic resonance imaging
Authors: Maier Andrea G. , Funovics Martin A. , Kreuzer Sören H. , Herbst Friedrich , Wunderlich Max , Teleky Bela K. , Mittlböck Martina , Schima Wolfgang , Lechner Gerhard L.
Published: August 2002

The purpose of this study was to compare prospectively the diagnostic yield of anal endosonography (AES) and magnetic resonance imaging (MRI) in the assessment of perianal fistulae and abscesses. There were 39 patients (14 men, 25 women; mean age, 40 years) who underwent AES, performed with a 10‐MHz rotating endoanal probe and MRI at 1.0 T (axial and coronal T2‐weighted turbo spin‐echo (TSE) and turbo‐STIR sequences). Fistulae were classified as subcutaneous, intersphincteric, transsphincteric, high (i.e., high extrasphincteric or suprasphincteric), rectovaginal, and horseshoe and were compared with the surgical findings in all patients. Overall, 58 fistulae (subcutaneous, N = 7; intersphincteric, N = 9; transsphincteric, N = 16; high, N = 17; rectovaginal, N = 5; and horseshoe, N = 4) were detected at surgery. MRI showed a sensitivity of 84% and AES of 60% (P < .05). False‐positive diagnoses were made in 6 patients (15%) with MRI and in 15 patients (26%) with AES, for a specificity of 68% and 21%, respectively (P < .05). Our findings show that MRI is superior to AES in the assessment of fistula‐in‐ano before major surgery. AES should be used only for orientation before minor procedures, such as incision or drainage of subcutaneous fistulae. J. Magn. Reson. Imaging 2001;14:254–260. © 2001 Wiley‐Liss, Inc.
The effect of injection rate on time‐resolved contrast‐enhanced peripheral MRA
Authors: Carroll Timothy J. , Korosec Frank R. , Swan J. Shannon , Hany Thomas F. , Grist Thomas M. , Mistretta Charles A.
Published: August 2002

In contrast‐enhanced (CE) magnetic resonance (MR) angiography (MRA), lower injection rates of a fixed contrast agent dose provide longer contrast agent bolus at the expense of lower intravascular signal. This study evaluated the effect of different injection rates in imaging of the vasculature of the lower extremities with time‐resolved, CE MRA. In three volunteers, injection rates of 0.5, 1.5 and 3.0 mL/second were administered in a randomized order and imaged in two separate sessions. Contrast agent bolus dynamics measured in volunteers were used in computer simulations to confirm variations in contrast agent concentration as a source of vessel ringing and blurring artifacts. To validate the effect of injection rate in pathologic vessels, 37 patients with peripheral vascular disease were imaged with a time‐resolved technique using an injection rate of 0.5 mL/second or 1.5 mL/second and retrospectively divided into two groups. In volunteers, higher injection rates caused a stronger modulation of k‐space and resulted in increased ringing artifacts in time‐resolved CE MRA. These results were reproduced with computer simulations. In the qualitative patient study, significantly less vessel blurring was observed using a lower injection‐rate, without a significant loss of vessel contrast. J. Magn. Reson. Imaging 2001;14:401–410. © 2001 Wiley‐Liss, Inc.
Quantitative analysis of memantine in human plasma by gas chromatography/negative ion chemical ionization/mass spectrometry
Authors: Leis Hans Jörg , Fauler Günter , Windischhofer Werner
Published: August 2002

A sensitive and specific method for the determination of memantine in human plasma is presented. Memantine was extracted from plasma and derivatized to the pentafluorobenzoyl derivative in a one‐step procedure avoiding any sample concentration steps. Adamantine was used as an internal standard. The compounds were measured by gas chromatography/negative ion chemical ionization mass spectrometry without any further processing. Using this detection mode, the fragment ions at m/z 353 and 325 were obtained at high relative abundance. Calibration graphs were linear over the range 0.117–30 ng ml−1. At the limit of quantification (LOQ), the inter‐assay precision was 2.00% and the intra‐assay variability was 3.22%. The accuracy at the LOQ showed deviations of −1.42% (intra‐assay) and −2.47% (inter‐assay). The method is rugged, rapid and robust and was applied to the batch determination of memantine during pharmacokinetic profiling of the drug. Copyright © 2002 John Wiley & Sons, Ltd.
Use of bacterially expressed EBNA‐1 protein cloned from a nasopharyngeal carcinoma (NPC) biopsy as a screening test for NPC patients
Authors: Chen Mei‐Ru , Liu Mei‐Ying , Hsu Shih‐Mei , Fong Chin‐Chu , Chen Chien‐Jen , Chen I‐How , Hsu Mow‐Ming , Yang Czau‐Siung , Chen Jen‐Yang
Published: August 2002

EBV serological tests have been used for many years as accessory diagnostic predictors of nasopharyngeal carcinoma (NPC). To increase the sensitivity and specificity of the NPC detection rate, a novel enzyme‐linked immunosorbent assay (ELISA) was established using a bacterially‐expressed GST‐EBNA‐1 protein, containing the EBNA‐1 sequence cloned from an NPC patient. Serum samples were collected from age‐ and gender‐matched patients with NPC, community control subjects and hospital control patients and tested using this ELISA. The positivity rates were 78.7% (247/314) in NPC, 11.5% (28/244) in hospital controls and 3.8% (10/263) in the community control group. These serum samples were also tested for IgA anti‐VCA antibodies and their ability to neutralize EBV DNase and the sensitivities of the anti‐VCA antibody and DNase‐neutralization tests also were analyzed. The optimum combination is VCA plus EBNA‐1, which can identify 92.5% (287/310) of NPC patients, and shows a specificity of 92.7% (242/261) for normal individuals. J. Med. Virol. 64:51–57, 2001. © 2001 Wiley‐Liss, Inc.
Phenotypic analysis of the sensitivity of HIV‐1 to inhibitors of the reverse transcriptase, protease, and integrase using a self‐inactivating virus vector system
Authors: Jármy Gergely , Heinkelein Martin , Weissbrich Benedikt , Jassoy Christian , Rethwilm Axel
Published: August 2002

Conventional phenotypic analysis of resistance of the human immunodeficiency virus (HIV) to antiviral therapy is time‐consuming and requires culture of infectious virus. Although phenotypic analyses may be desirable, rapid generation of test results and decentralized availability of the test system will be important to achieve utility in the clinical practice. This study describes the design of an alternative phenotypic resistance test using replication incompetent viral vectors. Chimeric HIV vectors containing a marker gene were generated. The env and most of the regulatory and accessory genes of HIV were removed. In addition, the 3′U3 region was deleted to obtain a self‐inactivating construct. Cotransfection of the plasmid with a plasmid that provided the vesicular stomatitis virus glycoprotein resulted in the production of replication‐incompetent virus vectors. Infection of susceptible cells with the vectors led to marker gene expression. Vector production in the presence of protease (PR) inhibitors, or infection in the presence of reverse transcriptase (RT) or integrase (IN) inhibitors reduced marker gene expression in a dose‐dependent manner. Marker gene activity was preserved at higher drug levels if vectors contained RT and PR genes from resistant virus isolates. Sensitivity to nucleoside and non‐nucleoside RT inhibitors, protease and integrase inhibitors could be determined in 10 working days. The phenotypic drug resistance test using replication‐incompetent HIV vectors significantly speeds up drug resistance measurements and allows testing at reduced biosafety levels. This will make clinical use of phenotypic assessment of antiviral resistance more feasible. J. Med. Virol. 64:223–231, 2001. © 2001 Wiley‐Liss, Inc.
Diagnosis of human parvovirus B19 infections by detection of epitope‐type‐specific VP2 IgG
Authors: Kaikkonen Leena , Söderlund‐Venermo Maria , Brunstein John , Schou Ole , Jensen Inge Panum , Rousseau Steve , Caul E. Owen , Cohen Bernard , Valle Martti , Hedman Lea , Hedman Klaus
Published: August 2002

In the B19 VP2 molecule an immunodominant heptapeptide epitope has been detected, recently for which IgG antibodies are synthesized exclusively in the acute phase of B19 infection. Using this acute‐phase‐specific epitope (KYVTGIN) a 2nd‐generation epitope‐type EIA was developed, which compares serum IgG activity for native VP2 capsids exhibiting conformational VP2 epitopes with IgG activity for the KYVTGIN epitope. In this study the diagnostic performance (clinical sensitivity and specificity) of the 1st and 2nd‐generation epitope‐type EIAs and of a peptide‐based EIA utilising as antigen the KYVTGIN epitope alone was assessed in comparison with various high‐quality IgM‐ and IgG‐ based B19 assays. Serum samples from 489 patients with B19‐related symptoms and asymptomatic controls from three countries were studied. Among 323 patients with B19‐IgG, 20% were diagnosed as acute infection, 73% had past immunity and 7% were not classified due to contradictory results among the different assays. The unclassified samples were explored for viral strain diversity by PCR and DNA sequencing but all sequences obtained were B19‐like with variance of only a few per cent. The 2nd‐generation epitope‐type EIA had a diagnostic sensitivity of 98% and a diagnostic specificity of 94%. In combination with conventional approaches, the epitope‐type assays increase greatly the accuracy of B19 serodiagnosis. J. Med. Virol. 64:360–365, 2001. © 2001 Wiley‐Liss, Inc.
Genetic heterogeneity of hepatitis E virus*
Authors: Schlauder George G. , Mushahwar Isa K.
Published: August 2002

Hepatitis E virus (HEV) infection has been considered a disease associated with developing regions and attributed to oral‐fecal transmission due to inadequate sanitation. Several recent findings, however, have led to a new understanding of this virus. A number of novel isolates have been identified in patients with acute hepatitis from regions not considered endemic for HEV, and these individuals reported no recent travel to HEV endemic areas. In addition, a number of HEV‐like sequences have also been isolated from swine worldwide, suggesting the potential of an animal reservoir. Although full‐length sequence is available for some strains, the majority of HEV isolates have only been sequenced partially. Sequence comparisons and phylogenetic analyses were performed to determine the genotypic distribution of HEV isolates, based on the partial sequence data available. It has been suggested that HEV isolates segregate into four major genotypes based on full‐length comparisons. These analyses, however, indicate that HEV may be distributed into at least nine different groups. J. Med. Virol. 65:282–292, 2001. © 2001 Wiley‐Liss, Inc.
Advanced model for simulation of surface‐emitting quantum‐well lasers
Authors: Ivanov P. S. , Lysak V. V. , Sukhoivanov I. A.
Published: August 2002

The radial heterogeneity of the vertical‐cavity surface‐emitting lasers (VCSEL) structure leads to both heterogeneity of the pumping current radial distributions and propagation conditions of the optical wave. Hence in research, it is necessary to make a more complete account of the carrier transport and photon generation processes of the devices mentioned.

In the given work we investigate a detailed mathematical model of the oxide‐confinement VCSEL with the advanced formulation of the material gain. It is possible to research thermal and speed characteristics of the device and to optimize the geometrical parameters of the laser structure. We consider that it is necessary to have identical radiuses both the oxide window and the quantum well for reduction of the delay time. Moreover, it is proved that the reducing oxide window radius leads to Gaussian distribution of radial photon distribution.

The carried out researches have shown the efficiency of the application of the given model for the analysis of the effects connected with the influence of the non‐linear carrier distribution on the VCSEL behaviour. This method can be useful for VCSEL structure optimization. Copyright © 2001 John Wiley & Sons, Ltd.