bluuebunny/crossref_metadata_2025_split huggingface dataset:
Radiosynthesis of 1‐(4‐(2‐[18F]fluoroethoxy)benzenesulfonyl)‐3‐butyl urea: a potential β‐cell imaging agent
Authors: Schirrmacher Ralf , Weber Michael , Schmitz Alexander , Shiue Chyng‐Yann , Alavi Abass A. , Feilen Peter , Schneider Stefan , Kann Peter , Rösch Frank 
Published: October 2002

AbstractTolbutamide (1) is a sulfonurea agent used to stimulate insulin secretion in type 2 diabetic patients. Its analogue 1‐(4‐(2‐[18F]fluoroethoxy)benzenesulfonyl)‐3‐butyl urea (3) was synthesized in overall radiochemical yields of 45% as a potential β‐cell imaging agent. Compound 3 was synthesized by 18F‐fluoroalkylation of the corresponding hydroxy precursor (2) with 2‐[18F]fluoroethyltosylate in DMF at 120°C for 10 min followed by purification with HPLC in a synthesis time of 50 min. Insulin secretion experiments of the authentic 19F‐standard compound on rat islets showed that the compound has a similar stimulating effect on insulin secretion as that of tolbutamide (1). The partition coefficient of compound 3 between octanol/water was determined to be 1.3±0.3 (n=5). Copyright © 2002 John Wiley & Sons, Ltd.
Fine structure and probable function of ring organs in the mite Histiostoma feroniarum (Acari: Actinotrichida: Acaridida: Histiostomatidae)
Authors: Witaliński Wojciech , Liana Marcin , Alberti Gerd 
Published: October 2002

AbstractHistiostoma feroniarum, like other histiostomatid mites, possesses peculiar ring organs that are visible under the light microscope as ventrally located, characteristic rings of sclerotized cuticle. The ring organ is composed of three elements: a disc of modified cuticle, ring organ cells located underneath the disc, and an “empty” chamber frequently visible between the cuticular disc and the cells. The cuticle of the disc is not perforated and differs from the surrounding unmodified cuticle as revealed by special staining developed for light microscopy and by electron microscopy. The ring organ cells show a polarity, with a practically smooth apical surface and an extremely folded basal membrane. The basal invaginations reach the apical cell portion, where they form tubular canaliculi distributed beneath the apical cell membrane. The cytoplasm contains many mitochondria, which are usually in contact with the cell membrane invaginations. Structurally, the ring organ cells closely resemble the transport cells described in osmoregulatory organs both in water‐inhabiting and terrestrial arthropods. Thus, our results support earlier suggestions of an osmoregulatory function performed by sclerotized rings (=ring organs), as an adaptation to aqueous environments. A possible homology with similar organs of other mites is discussed. J. Morphol. 253:255–263, 2002. © 2002 Wiley‐Liss, Inc.
Neurogenesis in the mossy chiton, Mopalia muscosa (gould) (polyplacophora): Evidence against molluscan metamerism
Authors: Friedrich Stefan , Wanninger Andreas , Brückner Martin , Haszprunar Gerhard 
Published: October 2002

AbstractNeurogenesis in the chiton Mopalia muscosa (Gould, 1846) was investigated by applying differential interference contrast microscopy, semithin serial sectioning combined with reconstruction techniques, as well as confocal laser scanning microscopy for the detection of fluorescence‐conjugated antibodies against serotonin and FMRFamide. The ontogeny of serotonergic nervous structures starts with cells of the apical organ followed by those of the cerebral commissure, whereas the serotonergic prototroch innervation, pedal system, and the lateral cords develop later. In addition, there are eight symmetrically arranged serotonergic sensory cells in the dorsal pretrochal area of the larva. FMRFamide‐positive neural elements include the cerebral commissure, specific “ampullary” sensory cells in the pretrochal region, as well as the larval lateral and pedal system. In the early juvenile the cerebral system no longer stains with either of the two antibodies and the pedal system lacks anti‐FMRFamide immunoreactivity. Outgroup comparison with all other molluscan classes and related phyla suggests that the cord‐like, nonganglionized cerebral system in the Polyplacophora is a reduced condition rather than a primitive molluscan condition. The immunosensitivity of the pedal commissures develops from posterior to anterior, suggesting independent serial repetition rather than annelid‐like conditions and there is no trace of true segmentation during nervous system development. Polyplacophoran neurogenesis and all other available data on the subject contradict the idea of a segmented molluscan stem species. J. Morphol. 253:109–117, 2002. © 2002 Wiley‐Liss, Inc.
Spermatophore transfer in the hermit crab Clibanarius vittatus (crustacea, anomura, diogenidae)
Authors: Hess Gregory S. , Bauer Raymond T. 
Published: October 2002

AbstractAlthough mating has been described in several hermit crab species, the mechanics of spermatophore transfer have not previously been demonstrated. Evidence from pleopod and gonopore morphology, video observations, and inseminated females indicates that in Clibanarius vittatus the male applies a spermatophoric mass directly onto the female via the gonopores rather than with modified pleopods 1–2 (gonopods) and/or genital papillae as in many other decapods. The single second pleopod of males of C. vittatus has a simple endopod with no apparent modifications for sperm transfer. There are no genital papillae extending from the male gonopores. The globular spermatophores are aligned in rows surrounded by a seminal secretion in the male ducts (vasa deferentia that terminate in ejaculatory ducts opening to the exterior via the gonopores). During copulation, described from time‐lapse video recordings, the ventral surface of the last thoracic segment of the male, bearing the gonopores, was apposed to the ventral cephalothorax of the female. A massive amount of seminal secretion containing spermatophore ribbons, termed here the spermatophoric mass and described for the first time in a hermit crab species, was observed covering the sternites and coxae of pereopods 1–5 of a recently copulated female. It is suggested that during copulation the male emits the contents of the ejaculatory ducts directly onto the female without the aid of gonopods or genital papillae. Although spermatophore transfer is simple in C. vittatus, the presence of modified anterior pleopods or elongate genital papillae (sexual tubes) in other paguroidean species suggests the possibility of a more complex insemination process in these other hermit crabs. J. Morphol. 253:166–175, 2002. © 2002 Wiley‐Liss, Inc.
Assessment of patellofemoral relationships using kinematic MRI: Comparison between qualitative and quantitative methods
Authors: Ward Samuel R. , Shellock Frank G. , Terk Michael R. , Salsich Gretchen B. , Powers Christopher M. 
Published: October 2002

AbstractPurposeTo compare the level of agreement between quantitative and qualitative methods in determining patellofemoral relationships, since controversy exists regarding the use of quantitative vs. qualitative criteria to interpret images of the patellofemoral joint (PFJ) obtained using kinematic magnetic resonance (MR) imaging.Materials and MethodsOne hundred twenty mid‐patellar axial plane images obtained using kinematic MR imaging from fifteen subjects were randomly selected for analysis. MR images represented various knee flexion angles ranging from 0 to 60 degrees. Quantitative analysis (bisect offset and patellar tilt angle) was performed by two examiners using a computer‐assisted software program. Based on data from previously published literature, MR images were characterized as demonstrating normal, medial, or lateral patellar subluxation, and/or normal, medial, or lateral tilt. Using similar categories, two different examiners experienced in reading MR images of the PFJ then applied qualitative criteria to the same images.ResultsThe average agreement between the quantitative and qualitative assessments of horizontal patellar displacement and patellar tilt ranged from poor to moderate (Kappa coefficient values of 0.27 and 0.45, respectively). Quantitative and qualitative techniques demonstrated acceptable intra‐ and inter‐observer reliability.ConclusionThese findings indicate that the use of quantitative criteria does not compare well to qualitative criteriain the analysis of kinematic MR images of the PFJ. One explanation for this discrepancy relates to the fundamental difference between the techniques. That is, quantitative measurements are based on the use of osseous landmarks, while the qualitative assessments tend to rely on a description of patellofemoral relationships based on joint surfaces. J. Magn. Reson. Imaging 2002;16:69–74. © 2002 Wiley‐Liss, Inc.
Intrahepatic arterioportal fistula: Demonstration by dynamic 3D magnetic resonance angiography in under four seconds
Authors: Balci N. Cem , Onat Levent , Karaman Kutlay , Şirvancı Mustafa 
Published: October 2002

AbstractWe report a case of a 35‐year‐old patient with clinical symptoms of portal hypertension that underwent dynamic contrast‐enhanced 3D magnetic resonance angiography (MRA) of the abdomen. On breath‐hold dynamic contrast‐enhanced MRA in less than 4 seconds, contrast passage from the arterial to the portal system was successfully demonstrated. Patient was managed according to MRA findings. J. Magn. Reson. Imaging 2002;16:94–96. © 2002 Wiley‐Liss, Inc.
In vivo animal functional MRI: Improved image quality with a body‐adapted mold
Authors: Landuyt Willy , Sunaert Stefan , Farina Davide , Meijerink Martijn , Béatse Eric , Van Hecke Paul , Hermans Robert , Marchal Guy , Lambin Philippe , Bosmans Hilde 
Published: October 2002

AbstractPurposeTo reduce functional magnetic resonance imaging (fMRI) susceptibility distortion at the air/tissue interphase in animal experiments.Materials and MethodsWe investigated the applicability of a body‐adaptable flexible mold consisting of a fast‐setting alginate. This technique was implemented for subcutaneous growing tumors in rats and for the brains of monkeys.ResultsThe T2*‐weighted gradient‐echo, echo‐planar imaging (GE‐EPI) data obtained with the body‐adapted mold showed a reduction of susceptibility artifacts and improved image quality. With both rat tumor and monkey brain, an optimized match with the anatomical T1 images was possible.ConclusionThe present mold methodology is a rapid, easy, and inexpensive way to reduce magnetic susceptibility during animal GE‐EPI. J. Magn. Reson. Imaging 2002;16:224–227. © 2002 Wiley‐Liss, Inc.
Simultaneous real‐time visualization of the catheter tip and vascular anatomy for MR‐guided PTA of iliac arteries in an animal model
Authors: Buecker Arno , Adam Gerhard B. , Neuerburg Joerg M. , Kinzel Sylvia , Glowinski Arndt , Schaeffter Tobias , Rasche Volker , van Vaals Joop J. , Guenther Rolf W. 
Published: October 2002

AbstractPurposeTo examine the feasibility of simultaneous MR real‐time active tip tracking and near real‐time depiction of the vascular anatomy for percutaneous angioplasty of iliac arteries under MR guidance.Materials and MethodsNine surgically created stenoses of external iliac arteries in pigs were dilated with MR‐compatible balloon catheters (Cordis, Roden, The Netherlands). These catheters were equipped with a microcoil for active tracking of the catheter tip with an in‐plane update rate of 10 positions per second. The procedures were performed on an interventional 1.5 T Gyroscan ACS‐NT scanner (Philips, Best, The Netherlands). Real‐time calculation of images acquired by radial k‐space filling was performed on a specially designed backprojector exploiting the sliding window reconstruction technique (Philips Research Laboratories, Hamburg, Germany). The image update rate was 20 frames per second using a radial gradient‐echo technique (TR = 12 msec, TE = 3.3 msec, 300 radials). MR angiography and X‐ray digital subtraction angiography on the X‐ray system positioned in‐line next to the interventional MR system served as control for the angioplasty results.ResultsReal‐time guidance and positioning of the balloon catheters was possible. The actual position of the catheter tip was indicated in the MR images without any time delay for the reconstruction of the anatomical MR images, which were updated with a rate of 20 frames per second. This yielded a combination of a roadmap and fluoroscopy image, in which the catheter position and the anatomical background image both were continuously updated in real time. Six out of nine stenoses were successfully dilated. The effects of the angioplasty could be visualized by the real‐time MR technique, as was proven by X‐ray digital subtraction angiography.ConclusionActive tip tracking simultaneous with MRI of the vascular anatomy—both in real time—is possible with the applied technique, enabling MR‐guided percutaneous dilatation (PTA) of iliac arteries. J. Magn. Reson. Imaging 2002;16:201–208. © 2002 Wiley‐Liss, Inc.
Initial experience with the intravascular contrast agent NC100150‐injection (Clariscan®) for breath‐hold and navigator‐gated magnetic resonance coronary artery imaging
Authors: Bunce Nicholas H. , Keegan Jennifer , Gatehouse Peter D. , Moon James C.C. , Firmin David N. , Hoffmann Volker , Pennell Dudley J. 
Published: October 2002

AbstractPurposeTo examine magnetic resonance coronary artery imaging after NC100150‐Injection.Materials and MethodsBreath‐hold and navigator‐gated images were acquired in five patients.ResultsBreath‐hold image quality, coronary artery‐fat SDNR, and coronary artery SNR improved. Respiratory artifacts due to reduced liver signal intensity degraded navigator‐gated image quality.ConclusionNC100150‐Injection improves breath‐hold coronary artery imaging. Navigator‐gated acquisitions should use techniques that are insensitive to T2* effects. J. Magn. Reson. Imaging 2002;16:217–223. © 2002 Wiley‐Liss, Inc.
Imaging articular cartilage defects in the ankle joint with 3D fat‐suppressed echo planar imaging: Comparison with conventional 3D fat‐suppressed gradient echo imaging
Authors: Ba‐Ssalamah Ahmed , Schibany Nadja , Puig Stefan , Herneth Andreas M. , Noebauer‐Huhmann Iris M. , Trattnig Siegfried 
Published: October 2002

AbstractPurposeTo shorten the examination time for articular cartilage imaging, using a recently developed three‐dimensional (3D) multishot echo planar imaging (EPI) sequence with fat saturated (FS), compared to aconventional 3D fat‐saturated spoiled gradient echo sequence (3D FS GRE).Material and MethodsThere were 32 consecutive patients with ankle joint disorders who underwent magnetic resonance imaging (MRI) in a 1.0‐T unit. Hyaline cartilage was imaged with a 3D FS EPI sequence and a 3D FS GRE sequence. Image assessment criteria included lesion conspicuity, contrast between different types of normal tissue, and image artifacts. In addition, contrast‐to‐noise ratios (CNRs) of cartilage vs. joint fluid and bone marrow were measured.ResultsThe 3D FS EPI sequence provided a high CNR between cartilage and subchondral bone, similar to that of the 3D FS GRE sequence. The CNR between cartilage and effusion was significantly lower on the 3D EPI sequence due to the higher signal intensity of fluid. Both sequences were equal in lesion detection ability. The image quality of the 3D FS GRE sequence was slightly higher than that of the 3D FS EPI, but the difference was not statistically significant.ConclusionWe conclude that the 3D FS EPI sequence is comparable to the 3D FS GRE sequence in the detection of cartilage lesions, with the additional advantage of reduction in scan time by a factor of 4. J. Magn. Reson. Imaging 2002;16:209–216. © 2002 Wiley‐Liss, Inc.
BOLD fMRI of the visual cortex: Quantitative responses measured with a graded stimulus at 1.5 Tesla
Authors: Mohamed Feroze B. , Pinus Alexander B. , Faro Scott H. , Patel Dhawal , Tracy Joseph I. 
Published: October 2002

AbstractPurposeTo measure and quantitatively characterize an activity generated by the neurons of the visual cortex (VC) in response to graded luminous intensity contrast stimuli using a 1.5 Tesla scanner.Materials and MethodsFunctional magnetic resonance imaging (fMRI) of the vc with the intrinsic blood oxygena‐tion level dependent (BOLD) mechanism was performed by using a paradigm with a 5 × 5 flashing checkerboard pattern flickering eight times per second at eight luminance contrasts presented in a randomized order. The changes of the luminance contrast were obtained by varying the luminance intensity of the white checkerboard squares. Each of eight trials, corresponding to eight luminance contrasts, consisted of six “rest” and six “activation” epochs, repeated five times, amounting to 60 measurement periods per trial. During each epoch, 10 contiguous oblique axial‐to‐coronal slices covering the calcarine fissure region and parallel to a line through the anterior‐posterior commissure (AC‐PC) markers were acquired using a gradient‐recalled echo planar imaging (GRE‐EPI) sequence.ResultsThe measurements showed changes in the activation extent in the VC following the stimulus' rising luminance intensity contrast. In addition, the fMRI signal in those activated areas present throughout all eight trials, referred to as “common” voxels in this report, showed an increasing trend as a function of the rising luminance intensity contrast.ConclusionThese results suggest that the processes of the neuronal recruitment that affects the extent and number of activated neurons, and the neuronal enhancement that defines the magnitude of the neuronal activation are dependent on the luminance intensity contrast. These changes can be visualized and quantified using BOLD fMRI at 1.5 Tesla. J. Magn. Reson. Imaging 2002;16:128–136. © 2002 Wiley‐Liss, Inc.
Identification of methyl salicylate as the principal volatile component in the methanol extract of root bark of Securidaca longepedunculata Fers
Authors: Jayasekara T. K. , Stevenson P. C. , Belmain S. R. , Farman D. I. , Hall D. R. 
Published: October 2002

AbstractSecuridaca longepedunculata Fers (Polygalaceae) is commonly used as a medicine in many parts of Africa and shows promise for protecting stored grain against insect pests. Analysis of a methanol extract of the root bark by gas chromatography linked to mass spectrometry (GC/MS) showed a major component accounting for over 90% of the volatile material. This was identified as methyl 2‐hydroxybenzoate (methyl salicylate) by comparison of the GC retention times and mass spectrum with those of synthetic standards. This conflicts with an earlier report that the major component is methyl 4‐hydroxybenzoate. Two minor components had mass spectra characteristic of 2‐hydroxybenzoate esters and were identified as methyl 2‐hydroxy‐6‐methoxybenzoate and its benzyl analogue, again conflicting with an earlier report. Copyright © 2002 John Wiley & Sons, Ltd.
Reactivation of human herpesvirus 6 and 7 in pregnant women
Authors: Ohashi Masahiro , Yoshikawa Tetsushi , Ihira Masaru , Suzuki Kyoko , Suga Sadao , Tada Shin , Udagawa Yasuhiro , Sakui Hisataka , Iida Keiji , Saito Yumiko , Nisiyama Yukihiro , Asano Yoshizo 
Published: October 2002

AbstractTo elucidate the roles of human herpesvirus (HHV)‐6 and ‐7 in pregnant women, peripheral blood samples and genital tract secretions were collected serially from pregnant women, and both serological testing and polymerase chain reaction (PCR) were carried out to detect viral DNA in the secretions. HHV‐6 or HHV‐7 Immunoglobulin(Ig)M antibodies were not detected in 432 plasma samples collected from pregnant women and cord blood, but IgG antibodies against both viruses were detected in all plasma samples. Significant increases in HHV‐6 and HHV‐7 IgG antibodies were observed in two (1.6%) and three (2.4%) pregnant women respectively of a total of 123 cases. HHV‐6 DNA was detected in the genital tract in three (3.7%) of 82 pregnant women at the first trimester, and in 10 (12.2%) of the same women in the third trimester. The detection rate in the third trimester was significantly higher than that in the first trimester (P = 0.043). Although HHV‐7 DNA was detected in the genital tract of two (2.7%) and seven (9.6%) pregnant women of a total of 73 during the first and third trimesters respectively, there was no statistical difference in the detection rate of the viral DNA between the trimesters. Because a significant increase in HHV‐6 IgG antibodies was detected in only two pregnant women, it was not possible to carry out statistical analysis to determine the relationship between HHV‐6 infection and associated clinical features. Although there was a significant increase in HHV‐7 antibody titers in three pregnant women, a positive correlation between the virus infection and the clinical features was not demonstrated. There was no statistical association between virus shedding in the genital tract and the clinical features examined in this study. J. Med Virol. 67:354–358, 2002. © 2002 Wiley‐Liss, Inc.
Sustained high proportion of zidovudine‐resistant HIV variants despite prolonged substitution of zidovudine by other nucleoside reverse transcriptase inhibitors
Authors: Bélec Laurent , Legoff Jérôme , Si‐Mohamed Ali , Andréoletti Laurent , Mbopi‐Kéou François‐Xavier , Kolberg Janice , Matta Mathieu , Detmer Jill , Piketty Christophe , Kazatchkine Michel D. 
Published: October 2002

AbstractThe consequences of zidovudine (ZDV) replacement by other nucleoside reverse transcriptase inhibitors on the expression of resistance mutations at codons 215 and 41 of the reverse transcriptase (RT) gene was investigated prospectively in 66 patients harboring mutant genotypes who were changed to an effective two‐ or three‐drug combination antiretroviral regimen. Quantitation of mutant (MUT) viral populations at codon 215 by means of RT‐PCR with differential hybridization of amplicons specific for MUT and wild (WT) variants revealed no difference in the proportion of 215 MUT variants prior to (93.5 ± 2.4%) and 12 to 20 months after (96.9 ± 1.9%) ZDV replacement, independently of a therapeutic change for stavudine. The fitness of the variants harboring the ZDV‐resistant MUT 215 genotype following drug withdrawal was calculated to be 96 to 99% of that of the variants harboring the WT 215 genotype. The apparent stability of ZDV‐resistant variants in the study population may have two main complementary explanations: persistent selective pressure secondary to partial cross‐resistance due to the new regimens given after the therapeutic alteration and suppression of viral replication after the therapeutic alteration that could have hampered the replacement of less fit variants by fitter variants. These findings indicate that, at least within 15 months following discontinuation of ZDV, an effective antiretroviral therapy is insufficient to allow for ZDV‐resistant strains to disappear, and thus to allow for the safe re‐introduction of the drug. J. Med. Virol. 68:1–6, 2002. © 2002 Wiley‐Liss, Inc.
Drift in the hypervariable region of the hepatitis C virus during 27 years in two patients
Authors: Gao Guang , Buskell Zelma , Seeff Leonard , Tabor Edward 
Published: October 2002

AbstractSerial serum samples were obtained over a 27‐year period from a hepatitis C virus (HCV)‐infected patient and from a nurse who appeared to become infected by this patient. The hypervariable region 1 (HVR1) and 5′noncoding region (5′NCR) of the HCV genome were amplified from each serum sample by polymerase chain reaction (PCR) and cloned. In the first serum specimen from the patient and the first two serum specimens from the nurse, most of the 20 clones from each serum sample had one common sequence in the HVR1 gene. All later serum samples contained a heterogeneous mixture of HCV quasispecies. The uniformity of the HVR1 sequence in the early samples and the emergence of greater diversity in later serum samples is consistent with the apparent transmission of HCV between the patient and nurse and the eventual emergence of other quasispecies as the virus replicated in the new host. In addition, the immune globulin given to the nurse may have been responsible for some of the HCV quasispecies changes observed in her serum. J. Med. Virol. 68: 60–67, 2002. © 2002 Wiley‐Liss, Inc.