bluuebunny/crossref_metadata_2025 huggingface dataset:
Growth inhibition due to complementation of transforming growth factor‐β receptor type II‐defect by human chromosome 3 transfer in human colorectal carcinoma cells
Authors: Miyafuji Yasunori , Zhong Xiaoling , Uchida Iichiro , Koi Minoru , Hemmi Hiromichi
Published: August 2002

The transforming growth‐β receptor type II (TGF‐βRII) gene is one of the target genes of the DNA mismatch repair (MMR) defect. The human colorectal carcinoma cell line HCT116 has mutations in the hMLH1 gene and in the microsatellite region of the TGF‐βRII gene, both located on the short arm of chromosome 3. Introduction of the wild‐type hMLH1 gene on transferred human chromosome 3 restores many characteristics of MMR‐deficiency in HCT116. In this study, we determined whether transfer of chromosome 3 into HCT116 also complements the TGF‐βRII gene defect. We compared in vitro growth characteristics between HCT116 and HCT116 with a transferred chromosome 3 (HCT116 + ch3). The growth was suppressed in HCT116 + ch3 compared with parental HCT116. This suppression was abolished by frequent replacement with fresh medium, suggesting that the autocrine TGF‐β‐TGF‐βRII system may be responsible for growth suppression. To explore this possibility, we determined several characteristics essential for the autocrine system. We found that HCT116 + ch3 expresses wild‐type as well as mutated TGF‐βRII mRNA. In addition, phosphorylation of TGF‐βRI and growth inhibition were observed in HCT116 + ch3 but not in HCT116 by exposure to exogenous TGF‐β. The amount of TGF‐β1 in HCT116 + ch3 cultures was remarkably less than that in the HCT116, suggesting that TGF‐β produced by HCT116 + ch3 cells may be consumed by the cells. The conditioned medium from HCT116 cultures inhibits HCT116 + ch3 growth. This inhibition was neutralized by the anti‐TGF‐β antibody. Taken together, these results strongly suggest that the TGF‐βRII gene defect in HCT116 is complemented by a wild‐type gene on the transferred chromosome 3 and that HCT116 + ch3 gained the ability to respond to TGF‐β. Simultaneous complementation of defects of a responsible gene and a major target gene by the chromosome transfer is useful to prove the inactivated phenotypes acquired during colorectal tumorigenesis. © 2001 Wiley‐Liss, Inc.
Sonography of the shoulder after arthrography (arthrosonography): Preliminary results
Authors: Lee Hak Soo , Joo Kyung‐Bin , Park Choong Ki , Kim Young Sun , Jeong Woo Kyeong , Kim Yong Soo , Park Dong Woo , Kim Sun Il , Park Tae Soo
Published: August 2002

Purpose

The purpose of this study was to verify whether arthrosonography improves diagnostic accuracy in diseases of the shoulder and provides additional information for therapeutic planning, compared with conventional sonography.

Methods

We prospectively studied 113 consecutive patients with chronic shoulder pain. Sonography was performed before and after arthrography, with the radiologist blinded to the results of arthrography. When a rotator cuff tear was detected sonographically, its type, location, and size were recorded; we also evaluated any changes in the subacromial‐subdeltoid bursa and any abnormalities in the biceps tendon sheath. The diagnostic accuracy of conventional sonography and arthrosonography was compared with that of arthrography for rotator cuff tear. Changes in the subacromial‐subdeltoid bursa and biceps tendon sheath seen on conventional sonography were also compared with those seen on arthrosonography.

Results

The sensitivity and specificity of conventional sonography in the diagnosis of rotator cuff tear were 86% (25/29) and 95% (80/84), respectively; for arthrosonography, the values were 97% (28/29) and 95% (80/84), respectively. The differences in sensitivity and specificity for the 2 sonographic techniques were not statistically significant (p > 0.05). The accuracy in localizing the tear was also not significantly different between the 2 sonographic techniques. Synovial proliferation was more easily detected with arthrosonography than it was with conventional sonography in the subacromial‐subdeltoid bursa (p < 0.01) and in the biceps tendon sheath (p < 0.0001).

Conclusions

Our preliminary results suggest that although arthrosonography was not superior to conventional sonography in the diagnosis of rotator cuff tears, it may provide a better assessment of the size of tears and additional information about synovial proliferation in the subacromial‐subdeltoid bursa and the biceps tendon sheath. © 2002 John Wiley & Sons, Inc. J Clin Ultrasound 30:23–32, 2002.
Sonographic evaluation of a uterine angiolipoleiomyoma
Authors: Braun Heidi L. , Wheelock John B. , Amaker Barbara H. , Seeds John W.
Published: August 2002

We report the case of a 51‐year‐old postmenopausal woman with an angiolipoleiomyoma, a rare mesenchymal uterine tumor, and describe its sonographic appearance. The clinical presentation of these invariably benign tumors often mimics that of uterine leiomyomas, making angiolipoleiomyomas difficult to diagnose correctly before histopathologic evaluation. In this case, sonography performed to determine the cause of the patient's vaginal bleeding showed a sharply marginated, brightly echogenic solid mass adjacent to the echogenic endometrium, without associated shadowing. Histopathologic examination revealed that this tumor was composed of smooth muscle, adipose tissue, fibrous connective tissue, and blood vessels. These sonographic findings, which are unusual for tumors of the uterus, suggest the diagnosis of angiolipoleiomyoma. Accurate diagnosis of these benign tumors could prevent patients from undergoing surgery and would allow appropriate counseling of patients. © 2002 Wiley Periodicals, Inc. J Clin Ultrasound 30: 241–244, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI: 10.1002/jcu.10057
Cutaneous seeding after ultrasound‐guided percutaneous ethanol injection for treatment of hepatocellular carcinoma
Authors: Casella Giovanni , Cacopardo Enea , Rovere Giuliano , Buda Carmelo Antonio , Cascinu Stefano , Baldini Vittorio
Published: August 2002

Cutaneous seeding is a rare complication of interventional ultrasound procedures. We describe a case of needle‐track cutaneous seeding of hepatocellular carcinoma (HCC) after sonographically guided percutaneous ethanol injection (PEI). In our case, the seeding might have been related to the type of needle used and the multiple passes required to treat the liver lesion. Despite the risk of needle‐track seeding, PEI remains useful in the treatment of HCC. © 2001 John Wiley & Sons, Inc. J Clin Ultrasound 29:354–358, 2001.
Regulation of oligodendrocyte development
Authors: Kagawa Tetsushi , Wada Tamaki , Ikenaka Kazuhiro
Published: August 2002

Oligodendrocytes are myelinating cells in the central nervous system. Recent studies demonstrated that oligodendrocyte progenitor cells are generated from a restricted region in the ventricular zone. In the rodent spinal cord, progenitor cells appear from narrow and bilateral longitudinal columns in the ventral ventricular zone, and then migrate dorsally. This ventral‐specific appearance of oligodendrocyte progenitors may be controlled along the dorso‐ventral axis in the spinal cord by extrinsic signals secreted from both the dorsal and ventral cords. The combined action of the Notch signaling pathway and a basic helix‐loop‐helix class of transcription factors may modulate this early specification of spinal oligodendrocytes and also be involved in multiple steps of oligodendrocyte differentiation. Microsc. Res. Tech. 52:740–745, 2001. © 2001 Wiley‐Liss, Inc.
Comparative view of pineal gland morphology of nocturnal and diurnal birds of tropical origin
Authors: Haldar C. , Bishnupuri K.S.
Published: August 2002

Although having a similar developmental pattern, the pineal gland of tropical birds varies in shape, size, and morphology, probably more than any other part of the avian brain. Following the old classification, we noted a solid follicular (transitional) type of the pineal gland in the nocturnal bird Athene brama, and a tubulo‐follicular and elongated tubular types of pineal gland in diurnal birds Perdicula asiatica and Euroloncha punchulata, respectively. Detailed light (LM) and electron microscopic (EM) studies of the pineal gland from these tropical birds revealed the presence of a well‐developed, functionally active gland in nocturnal birds (contrary to reports available until now). Unlike diurnal birds, the nocturnal bird A. brama has no deep pineal in the posterior region (near the habenular commissure). It could be that the deep encephalic receptors have no/fewer functions in nocturnal birds. At present, we were unable to define the significance of deep pineal in these tropical avian species. A notable difference in the proximodistal orientation of intrapineal follicles and parenchymatous cells was noted among these birds due to different habitats. Ultrastructurally, the pinealocytes exhibited great similarities in terms of secretory organelles, except for the presence of some peculiar membranous structure in E. punchulata. The pinealocytes have rudimentary photoreceptive features (e.g., outer segment) along with cytoplasmic organelles for secretory activity, suggesting both photosensory and photosecretory types of function. The present study also suggests more heterogenicity in pineal gland morphology (cellular architecture) among diurnal birds than the nocturnal one. Microsc. Res. Tech. 53:25–32, 2001. © 2001 Wiley‐Liss, Inc.
Immunoregulation of microglial functional properties
Authors: Cross Alison K. , Woodroofe M. Nicola
Published: August 2002

Microglia are the resident tissue macrophages of the central nervous system (CNS) parenchyma and are key players in the initiation of an inflammatory response. Microglia rapidly transform from a resting to an activated morphology in response to a variety of disease states. However, they can also be the target of infections, as in the case of HIV. Many of the effector properties of microglia can be attributed to the array of substances they secrete in response to stimuli such as bacterial lipopolysaccharide, cytokines, and chemokines. The products of activated microglia include: cytokines (pro‐ and anti‐inflammatory), chemokines, nitric oxide, superoxide radicals, and proteases. Furthermore, microglia have the ability to present antigen to T cells, migrate in response to chemotactic stimuli, and phagocytose cell debris. This report focuses on the immunomodulatory functions of microglia, with particular attention to chemokines, and highlights their pivotal role in the CNS. Microsc. Res. Tech. 54:10–17, 2001. © 2001 Wiley‐Liss, Inc.
Influence of incubation temperature on hatching success, energy expenditure for embryonic development, and size and morphology of hatchlings in the oriental garden lizard, Calotes versicolor (Agamidae)
Authors: Ji Xiang , Qiu Qing‐Bo , Diong Cheong‐Hoong
Published: August 2002

We incubated eggs of Calotes versicolor at four constant temperatures ranging from 24°C to 33°C to assess the effects of incubation temperature on hatching success, embryonic use of energy, and hatchling phenotypes that are likely to affect fitness. All viable eggs increased in mass throughout incubation due to absorption of water, and mass gain during incubation was dependent on initial egg mass and incubation temperature. The average duration of incubation at 24°C, 27°C, 30°C, and 33°C was 82.1 days, 60.5 days, 51.4 days, and 50.3 days, respectively. Incubation temperature affected hatching success, energy expenditure for embryonic development, and several hatchling traits examined, but it did not affect the sex ratio of hatchlings. Hatching success was lowest (3.4%) at 33°C, but a higher incidence of deformed embryos was recorded from eggs incubated at this temperature compared to eggs incubated at lower temperatures. Most of the deformed embryos died at the last stage of incubation. Energy expenditure for embryonic development was, however, higher in eggs incubated at 33°C than those similarly incubated at lower temperatures. A prolonged exposure of eggs of C. versicolor at 33°C appears to have an adverse and presumably lethal effect on embryonic development. Hatching success at 24°C was also low (43.3%), but hatchlings incubated at 24°C did not differ in any of the examined traits from those incubated at two intermediate temperatures (27°C and 30°C). Hatchlings incubated at 33°C were smaller (snout‐vent length, SVL) than those incubated at lower incubation temperatures and had larger mass residuals (from the regression on SVL) as well as shorter head length, hindlimb length, tympanum diameter, and eye diameter relative to SVL. Hatchlings from 33°C had significantly lower scores on the first axis of a principal component analysis representing mainly SVL‐free head size (length and width) and fore‐ and hindlimb lengths, but they had significantly higher scores on the second axis mainly representing SVL‐free wet body mass. Variation in the level of fluctuating asymmetry in eye diameter associated with incubation temperatures was quite high, and it was clearly consistent with the prediction that environmental stress associated with the highest incubation temperatures might produce the highest level of asymmetry. Newly emerged hatchlings exhibited sexual dimorphism in head width, with male hatchlings having larger head width than females. J. Exp. Zool. 292:649–659, 2002. © 2002 Wiley‐Liss, Inc.
Oviducal sperm storage in turkeys: Spatial distribution of sperm within the uterovaginal junction sperm‐storage tubules
Authors: Bakst Murray R. , Vinyard Bryan T.
Published: August 2002

The spatial distribution of sperm within the sperm storage tubules (SST) found in the uterovaginal junction (UVJ) of the turkey is not known. In this study, we inseminated sperm stained with a fluorescent dye (Hoechst 33342) to determine their distribution in SST in the ventral, dorsal, and lateral regions of the proximal, middle, and distal regions of the UVJ. There was no preferential filling in the ventral‐dorsal axis of the UVJ. In contrast, preferential filling of the SST was observed in the middle section of the UVJ. Here the individual SST were clearly longer and more pleomorphic than the SST in the more proximal and distal aspects of the UVJ. While no information on the temporal aspect of SST filling by sperm could be gleaned, it is evident that the more morphologically developed SST either accept sperm more readily or store sperm more efficiently than SST elsewhere in the UVJ. J. Exp. Zool. 292:206–209, 2002. © 2002 Wiley‐Liss, Inc.
Hamilton weights and Petersen minors*
Authors: Lai Hong‐Jian , Zhang Cun‐Quan
Published: August 2002

A (1, 2)‐eulerian weight w of a cubic graph is called a Hamilton weight if every faithful circuit cover of the graph with respect to w is a set of two Hamilton circuits. Let G be a 3‐connected cubic graph containing no Petersen minor. It is proved in this paper that G admits a Hamilton weight if and only if G can be obtained from K4 by a series of Δ↔Y‐operations. As a byproduct of the proof of the main theorem, we also prove that if G is a permutation graph and w is a (1,2)‐eulerian weight of G such that (G, w) is a critical contra pair, then the Petersen minor appears “almost everywhere” in the graph G. © 2001 John Wiley & Sons, Inc. J Graph Theory 38: 197–219, 2001
A list version of Dirac's theorem on the number of edges in colour‐critical graphs
Authors: Kostochka Alexandr V. , Stiebitz Michael
Published: August 2002

One of the basic results in graph colouring is Brooks' theorem [R. L. Brooks, Proc Cambridge Phil Soc 37 (1941) 194–197], which asserts that the chromatic number of every connected graph, that is not a complete graph or an odd cycle, does not exceed its maximum degree. As an extension of this result, Dirac [G. A. Dirac, Proc London Math Soc 7(3) (1957) 161–195] proved that every k‐colour‐critical graph (k ≥ 4) on n ≥ k + 2 vertices has at least ½((k − 1) n + k − 3) edges. The aim of this paper is to prove a list version of Dirac's result and to extend it to hypergraphs. © 2002 Wiley Periodicals, Inc. J Graph Theory 39: 165–177, 2002; DOI 10.1002/jgt.998
Organoiridium catalysed hydrogen isotope exchange of benzamide derivatives
Authors: Valsborg Jacob S. , Sørensen Lone , Foged Christian
Published: August 2002

Hydrogen‐tritium exchange in a series of benzamide derivatives and acetanilide has been investigated using [Ir(cod)(Cy3P)(Py)]PF6 as catalyst. Specific activities of 6–43 Ci/mmol were obtained. Tritium NMR spectroscopy showed that exchange occurred ortho to the amide group. Copyright © 2001 John Wiley & Sons, Ltd.
Patterns of carpal development among anuran amphibians
Authors: Fabrezi Marissa , Barg Mónica
Published: August 2002

The unity and diversity of developmental processes in the vertebrate limb have singular importance in the interpretation of evolutionary hypotheses of tetrapod diversification. In anurans, the intraordinal diversity of forelimbs seems to be related to the fusion of distal carpals, whereas proximal carpals are invariable. However, there are different ontogenetic pathways involved in the differentiation of proximal carpals. This study presents a comparative analysis of early developmental features in one archeobatrachian and 23 neobatrachian species representing five families and explores the variability in the differentiation of carpal cartilages. We found new evidence supporting the presence of an embryonic intermedium that incorporates with the ulnare. Difference between the pipid Xenopus and the neobatrachians is interpreted as a change in the rate of differentiation of Distal Carpal 5 that does not affect the developmental pattern of digits. The developmental variability exhibited by the intermedium, radiale, and Element Y is combined in patterns that converge on the same adult carpal morphology among neobatrachians; these patterns appear to contain potentially useful phylogenetic information. J. Morphol. 249:210–220, 2001. © 2001 Wiley‐Liss, Inc.
Deformation and three‐dimensional displacement of fibers in isometrically contracting rat plantaris muscles
Authors: Savelberg Hans H.C.M. , Willems Paul J.B. , Baan Guus C. , Huijing Peter A.
Published: August 2002

In this study, the deformation of different fibers of the rat m. plantaris during “isometric” contractions at different muscle lengths was considered. Because the m. plantaris has an obviously inhomogeneous architecture, its fibers on the medial side of the muscle belly are judged to be shorter than those on the lateral side of it. It was expected that longitudinal deformation of different fibers would vary accordingly. A 3D video analysis of contracting muscle showed that longitudinal strain of fibers as a function of muscle length does not differ between fibers on different sides of the muscle. Apart from longitudinal shortening, the fibers were also displaced laterally during a contraction. The fibers displaced during a contraction in a direction perpendicular to their longitudinal axis. The displacement of the fibers occurred asymmetrically, resulting in a helical deformation of the whole muscle. It is concluded that the asymmetric displacement and the helical deformation must result from transversal forces between the fibers. It is hypothesized that these transversal forces cancel out differences in longitudinal strains that might exist between fibers. J. Morphol. 250:89–99, 2001. ©2001 Wiley‐Liss, Inc.
Small bowel MRI: Comparison of a polyethylene glycol preparation and water as oral contrast media
Authors: Sood Rohit R. , Joubert Ilse , Franklin Hilary , Doyle Terence , Lomas David J.
Published: August 2002

Purpose

To compare water and a polyethylene glycol (PEG) preparation as potential oral contrast media for magnetic resonance imaging (MRI) of the small bowel.

Materials and Methods

Twenty‐two healthy volunteers underwent separate MRI examinations after drinking up to two liters of water or PEG preparation. Small bowel images were obtained every 10 minutes for at least two hours using breath‐hold single shot half‐Fourier imaging, including both thick section projection and thin section images. Examinations were evaluated by two radiologists in consensus, blinded to the volunteer and contrast details, for arrival at the terminal ileum, transit time, and demonstration of small bowel segments.

Results

The PEG preparation was significantly better than water at reaching the terminal ileum (PEG 21/22 volunteers [95.45%], water 14/22 volunteers [63.6%], P = 0.04). There was no significant difference in the mean transit time (water 51 ± 48 minutes, PEG 37.7 ± 22 minutes) or in the demonstration of the stomach, duodenum, and jejunum, but the PEG preparation was significantly better at demonstrating the ileum (P = 0.005) and terminal ileum (P = 0.002).

Conclusion

A PEG preparation is significantly better than water as an oral contrast medium for demonstrating the distal small bowel during breath‐hold T2‐weighted MRI. J. Magn. Reson. Imaging 2002;15:401‐408. © 2002 Wiley‐Liss, Inc.
In vivo diffusion‐weighted MRI of the breast: Potential for lesion characterization
Authors: Sinha Shantanu , Lucas‐Quesada Flora Anne , Sinha Usha , DeBruhl Nanette , Bassett Lawrence W.
Published: August 2002

Purpose

To investigate the potential of apparent diffusion coefficients (ADCs) in characterizing breast lesions in vivo.

Materials and Methods

Two diffusion‐weighted (DW) sequences were implemented on a 1.5 Tesla scanner, with low b‐value orthogonal and high b‐value tetrahedral sensitized sequences. The orthogonal sequence was evaluated on 16 normal volunteers and 23 patients with known lesion types (six benign and 17 malignant). The tetrahedral sequence was evaluated on a smaller number of subjects: two normal, two malignant, and two benign.

Results

The mean value of the ADC of the malignant tumors was reduced compared to that of the benign lesions and normal tissue. This finding was related to the increased cellularity of the malignant lesions. The ADC values were elevated for all tissue types with the low b‐value sequence as compared to the high b‐value sequence, indicating contributions from perfusion effects at the low b‐values.

Conclusion

The study clearly shows that DW‐MRI can help characterize breast lesions in vivo. J. Magn. Reson. Imaging 2002;15:693–704. © 2002 Wiley‐Liss, Inc.
MRI vs. histologic measurement of breast cancer following chemotherapy: Comparison with x‐ray mammography and palpation
Authors: Weatherall P.T. , Evans Gregory F. , Metzger Gregory J. , Saborrian M. Hossein , Leitch A. Marilyn
Published: August 2002

Twenty consecutive patients with breast cancer were evaluated following chemotherapy using MRI to assess the size of cancer residua and compare these data with subsequent histologic measurements of the viable tumor. This retrospective study also involved assessment of the preoperative size of the malignancy as determined by physical exam and x‐ray mammogram. These values were later compared with the histology. The tumor size correlation coefficient between MRI and pathologic analysis was the highest, at 0.93. Physical exam and x‐ray mammography (available for 17 patients) produced correlation coefficients of 0.72 and 0.63, respectively, compared to histologic measurement. The accuracy of MRI did not vary with the size of cancer residua. MRI is an accurate method for preoperative assessment of breast cancer residua following chemotherapy. J. Magn. Reson. Imaging 2001;13:868–875. © 2001 Wiley‐Liss, Inc.
MR lung imaging at 0.2 T with T1‐weighted true FISP: Native and oxygen‐enhanced
Authors: Müller C. J. , Löffler R. , Deimling M. , Peller M. , Reiser M.
Published: August 2002

An inversion recovery true fast imaging with steady precession (FISP) pulse sequence was developed to carry out fast imaging of the lungs at 0.2 T. Using this sequence, oxygen‐enhanced magnetic resonance (MR) lung imaging was performed on healthy volunteers. The lungs showed signal enhancement (11.7% ± 3.8%) when breathing 100% oxygen. Using inversion recovery, true FISP at low field may prove promising for MR lung imaging. J. Magn. Reson. Imaging 2001;14:164–168. © 2001 Wiley‐Liss, Inc.
MRI assessment of microvascular characteristics in experimental breast tumors using a new blood pool contrast agent (MS‐325) with correlations to histopathology
Authors: Turetschek Karl , Floyd Eugenia , Helbich Thomas , Roberts Timothy P.L. , Shames David M. , Wendland Michael F. , Carter Wayne O. , Brasch Robert C.
Published: August 2002

A new contrast medium, MS‐325, was compared to albumin‐(Gd‐DTPA)30 in 18 chemically induced rat breast tumors based on quantitative estimates of microvascular permeability (KPS) and fractional plasma volume (fPV) using a two‐compartment bidirectional model. No significant correlation was found between MS‐325‐enhanced microvascular assays with either tumor grade or with microvascular counts (MVCs). In comparison, the correlation coefficient between KPS and histologic tumor grade using albumin‐(Gd‐DTPA)30 (r = .58) was statistically significant (P < .01). Also, using albumin‐(Gd‐DTPA)30, a significant correlation (r = .55, P < .05) was observed between the KPS and MVC, a biomarker of angiogenesis. Correlations between fPV and MVC were not statistically significant for either contrast medium. In conclusion, using MS‐325, no significant correlations between the MR‐estimated permeability values or plasma volumes were observed in experimental breast tumors with either the histologic tumor grade or MVC. This analysis confirms our previous determination that capillary permeability estimates, using a prototype large molecular contrast medium, albumin‐(Gd‐DTPA)30, correlate significantly with both histologic tumor grade and MVC. J. Magn. Reson. Imaging 2001;14:237–242. © 2001 Wiley‐Liss, Inc.
Comparison between solution‐phase stability and gas‐phase kinetic stability of oligodeoxynucleotide duplexes
Authors: Gabelica Valérie , Pauw Edwin De
Published: August 2002

The relative kinetic stabilities of different 16‐mer oligonucleotide duplexes were investigated by source collision‐induced dissociation (CID) in a heated capillary electrospray ion source. They were compared with the relative stabilities in solution obtained by thermal denaturation monitored by UV spectrophotometry. The results clearly show that both hydrogen bonding and base stacking interactions that are present in solution are maintained in the gas phase. This suggests that the electrospray process preserves the double‐helix structure of DNA. A step by step opening of the double helix structure is proposed for the gas‐phase dissociation, competing with the covalent bond cleavage of bases. We also draw attention to the fact that by source CID, it is the kinetic stability of the complexes that is probed. In particular, this implies that only complexes of the same size can be compared. Copyright © 2001 John Wiley & Sons, Ltd.
Identification of ozone‐oxidation products of oxycodone by electrospray ion trap mass spectrometry
Authors: Pennanen Keijo , Kotiaho Tapio , Huikko Katri , Kostiainen Risto
Published: August 2002

The products of oxycodone oxidized by ozone were characterized by electrospray ionization–tandem mass spectrometry (ESI–MS/MS). Liquid Chromatography(LC)–MS analyses revealed that the main constituents in the oxidation reaction mixture included the protonated molecules m/z 316, corresponding to oxycodone, and m/z 332, m/z 348, m/z 366, corresponding to the oxidation products. ESI–MS/MS and MSn spectra were used to study oxycodone fragmentation in detail and to characterize the structures of oxidation products. The results show that the oxidation products were formed by addition of one or two oxygen atoms or by addition of three oxygen and two hydrogen atoms to oxycodone. The fragmentation of the oxidation products also shows that the aromatic ring oxidizes due to rupture of the C‐3C‐4 bond during product formation. Copyright © 2001 John Wiley & Sons, Ltd.
Electrospray ionization mass spectrometry of tribenzyltin substituted‐phenoxyacetate compounds
Authors: Wei Junhua , Miller Jack Martin
Published: August 2002

Hydrolysis products of organotin compounds RC6H4OCH2COOSn(CH2ph)3 (R = o‐NO2, 1; m‐NO2, 2; p‐NO2, 3; o‐CH3, 4; o‐OCH3, 5; o‐Cl, 6; o‐Br, 7) and RC6H3OCH2COOSn(CH2ph)3 (R = o,o‐2CH3, 8, o‐OCH3, p‐CHO, 9; o,p‐2Cl, 10), produced in aqueous acetonitrile solution, have been investigated by electrospray mass spectrometry (MS) and MSn techniques. The complexes [Y2SnXR′]−, [Y3SnXR′]−, [Y3SnX2R′]−, [Y2SnX3R′]−, and fragment ions of [Y3SnR′]−, plus abundant RC6H4(or RC6H3)OCH2COO− and RC6H4(or RC6H3)O− ions are observed in negative mode, whereas the protonated molecular ion [M + H]+, complexes [Y2SnXR′]+, [Y3SnXR′]+, [Y2SnX2R′]+, [Y3SnX2R′]+, [Y2SnX3R′]+, [Y3SnX3R′]+, as well as [YSnXR′]+, [M − CH2ph]+, XSn+, (phCH2)3Sn+, phCH2Sn+ (Y = CH2ph, X = OOCCH2OC6H4R(or C6H3R)) are detected in the positive mode. Water adduct ions are seen in both modes. The assignments are facilitated by agreement between observed and calculated isotopic patterns and tandem mass spectrometry studies. Copyright © 2001 John Wiley & Sons, Ltd.
Structural assignment of isomeric 2‐(2‐quinolinyl)‐1H‐indene‐1,3(2H)‐dione mono‐ and disulfonic acids by liquid chromatography electrospray and atmospheric pressure chemical ionization tandem mass spectrometry
Authors: Weisz Adrian , Andrzejewski Denis , Fales Henry M. , Mandelbaum Asher
Published: August 2002

Positionally isomeric 2‐(2‐quinolinyl)‐1H‐indene‐1,3(2H)‐dione mono‐ and disulfonic acids give rise to similar electrospray ionization (ESI) and atmosphere pressure chemical ionization (APCI) mass spectra, which show very abundant MH+ ions and negligible fragmentation. The MH+ ions of these isomeric acids exhibit notably different behavior under collision‐induced dissociation (CID) conditions. The acids with a sulfonic group at position 8′ in the quinoline moiety, adjacent to the N‐atom, exhibit highly abundant [MH − H2SO3]+ ions (m/z 272 for the mono‐ and m/z 352 for the disulfonic acids), which are of lower abundance in the CID spectra of isomers with the SO3H group at other positions, remote from the nitrogen atom. The latter isomers undergo efficient eliminations of SO3 and HSO3. The isomeric diacids with one SO3H group at position 4 of the indene‐1,3(2H)‐dione moiety, adjacent to one of the carbonyl groups, undergo highly efficient elimination of H2O. Mechanistic pathways, involving interactions between adjacent groups, are proposed for the above regiospecific fragmentations. Pronounced different behavior has been also observed in negative ion tandem mass spectrometric measurements of the sulfonic acids. The distinctive behavior of the isomeric acids was strongly pronounced when the measurements were performed with an ion trap mass spectrometer (LCQ), and much less so with a triple‐stage quadrupole instrument (TSQ). Published in 2001 by John Wiley & Sons, Ltd.
Atmospheric pressure chemical ionization mass spectrometric and visible spectrophotometric studies of copper(I) and copper(II) complexes with 2‐(5‐bromo‐2‐pyridylazo)‐5‐diethylaminophenol
Authors: Oszwałdowski Sławomir , Witowska Janina , Jarosz Maciej
Published: August 2002

Complexes of copper(II) with 2‐(5‐bromo‐2‐pyridylazo)‐5‐diethylaminophenol (5‐Br‐PADAP) formed in aqueous methanol in a wide range of pH (from acidic to alkaline) as well as copper(I)–5‐Br‐PADAP species formed in methanolic solutions were investigated by spectrophotometry and mass spectrometry. Pseudomolecular and fragment ions created in the atmospheric pressure chemical ionization (APCI) source confirmed the molecular masses of the complexes existing in the solvents and their structures. The structure of the Cu(II) complex with 5‐Br‐PADAP formed in acidic medium was proposed as CuR(R − H) (where R is the undissociated molecule of the reagent). The binding sites of the two bound reagent molecules were different: in one of them the oxygen atom of the dissociated phenolic group and the nitrogen atom from the azo (—NN—) group took part in complex formation, whereas in the other only nitrogen atoms from the pyridyl ring and azo group were involved. The complex was stable and could not be reduced to Cu(I) species by use of standard reducing agents (ascorbic acid, hydroxylamine). In alkaline solutions the complex tended to polymerize and precipitated in media containing less than 80% of methanol. The copper(I)–5‐Br‐PADAP complex was extremely unstable and could be obtained (as a mixture with Cu(II) species) in media free of water or oxygen. For this complex, CuR2 was proposed as the most probable structure. According to this proposal copper(I) reacted exclusively with nitrogen‐containing binding sites and the undissociated phenolic group was not engaged in complex formation. In this system Cu(I)/Cu(II) electron transfer is very rapid, accelerated by a polar environment, e.g. in the presence of water molecules or dissolved oxygen. Copyright © 2001 John Wiley & Sons, Ltd.
Structural characterization of isoxazolidinyl nucleosides by fast atom bombardment tandem mass spectrometry
Authors: Colacino Evelina , Giorgi Gianluca , Liguori Angelo , Napoli Anna , Romeo Roberto , Salvini Laura , Siciliano Carlo , Sindona Giovanni
Published: August 2002

4′‐Aza‐2′,3′‐dideoxyerythrofuranosyl derivatives of thymine (AdT, 1) and uracil (AdU, 2) are analogues of 2′,3′‐dideoxyribofuranosyl thymine (ddT, 3) and uracyl (ddU, 4). Compounds 1 and 2 are representative of a new class of antiviral agents where the sugar moiety is replaced by an isoxazolidine ring. The increasing importance of isoxazolidinyl nucleosides has encouraged the exploitation of simple mass spectrometric rules for unambiguously assigning their structure. The species 1, 2, 5 and 6 were therefore synthesized in order to evaluate the role of the basic centre of the modified sugar moiety in their gas‐phase chemistry. The tandem mass spectra of these compounds are similar to those of the wild‐type nucleosides and display fragment ions corresponding to [B + 2H]+,[M − BH]+ and [B + 27]+ species, where B is the nucleobase. The last species derives from a retrocycloaddition process which is less evident in 2′‐deoxyribosides. This behaviour is consistent with protonation of the analytes at the pyrimidine rings. Model isoxazolidines, in which the nucleobase was replaced by a phenyl or a naphthyl moiety, displayed the expected behaviour of species with a localized charge on the N—O moiety of the isoxazolidine ring. Copyright © 2001 John Wiley & Sons, Ltd.
Hepatitis B virus genotypes and HBsAg subtypes in refugees and injection drug users in the United States determined by LiPA and monoclonal EIA
Authors: Swenson Paul D. , Van Geyt Caroline , Alexander E. Russell , Hagan Holly , Freitag‐Koontz Jayne M. , Wilson Shari , Norder Heléne , Magnius Lars O. , Stuyver Lieven
Published: August 2002

Hepatitis B virus (HBV) genotyping and hepatitis B surface antigen (HBsAg) subtyping were carried out on sera from 196 HBsAg‐positive patients, including 151 refugees entering the United States and 45 injection drug users in Seattle. HBsAg subtyping was performed by enzyme immunoassay (EIA) using a panel of monoclonal antibodies and the HBV genotype was determined by polymerase chain reaction (PCR) followed by detection of amplified HBV DNA by a reverse‐phase hybridization line probe assay (LiPA) using genotype‐specific probes. HBV DNA was detected by PCR in 155 (79%) of the 196 sera and all 155 were genotyped by LiPA. Samples from Southeast Asia were predominantly genotype B/subtype ayw1 and genotype C/adr; samples from the former Soviet Union and eastern Europe were mostly genotype D/ayw2 and genotype D/ayw3; samples from east Africa were mainly genotype A/adw2 and genotype D/ayw2; and samples from injection drug users were mostly genotype D/ayw3 and genotype A/adw2. Some strains of ayw3 gave atypical monoclonal antibody reactivity patterns in the subtyping assay due to a Val/Ala instead of a Thr at amino acid residue 118 and a Thr instead of a Met at residue 125. A strain of ayw2 also gave an atypical monoclonal antibody reactivity pattern due to an Ala instead of a Thr at amino acid residue 123. LiPA genotyping and monoclonal EIA subtyping can provide useful information for epidemiological studies. J. Med. Virol. 64:305–311, 2001. © 2001 Wiley‐Liss, Inc.
Administration of a human monoclonal antibody (TUVIRUMAB) to chronic hepatitis B patients pre‐treated with lamivudine: monitoring of serum TUVIRUMAB in immune complexes
Authors: Heijtink R.A. , van Nunen A.B. , van Bergen P. , Östberg L. , Osterhaus A.D.M.E. , de Man R.A.
Published: August 2002

A human monoclonal anti‐hepatitis B antibody preparation (TUVIRUMAB) was administered 6 times over a 2‐week period in a dose‐escalating scheme to chronic hepatitis B patients pre‐treated with lamivudine. The capacity of the TUVIRUMAB antibody to “neutralize” hepatitis B surface antigen in the circulation was investigated by means of experimental enzyme‐immunoassays. Monoclonal antibody conjugates enabled the detection of HBsAg, TUVIRUMAB, and HBsAg/TUVIRUMAB complexes. The results showed that (1) TUVIRUMAB was able partially to “neutralize” in vitro and in vivo, (2) HBsAg/TUVIRUMAB complexes can be traced by assays that capture the complex at either its HBsAg or its TUVIRUMAB component, (3) the final concentration of TUVIRUMAB at the end of therapy varied greatly but seemed to be related to HBsAg production at the start of therapy, (4) for at least 14 days after discontinuation of therapy, a minimal HBsAg level could be maintained in the presence of a declining TUVIRUMAB titer in patients with less than 3 μg/ml HBsAg before the start of therapy, (5) three months after therapy, all HBsAg levels had returned to pre‐treatment levels and TUVIRUMAB had disappeared. J. Med. Virol. 64:427–434, 2001. © 2001 Wiley‐Liss, Inc.
Genetic analysis of hepatitis a virus outbreak in france confirms the co‐circulation of subgenotypes Ia, Ib and reveals a new genetic lineage
Authors: Costa‐Mattioli Mauro , Monpoeho Serge , Schvoerer Claire , Besse Bernard , Aleman Marie‐Helene , Billaudel Sylviane , Cristina Juan , Ferré Virginie
Published: August 2002

Genetic analysis of selected genome regions of hepatitis A Virus (HAV) suggested that distinct genotype could be defined in different geographic locations. In order to study the degree of genetic variability among HAV isolated during a single epidemic outbreak, sequences from a 148 base pair segment within the VP1 amino terminal region were obtained for eight distinct HAV isolates from an outbreak that occurred in North Bretagne (France). These sequences were compared among themselves and with published sequences from 30 different strains that represented different HAV sub‐genotypes that were isolated all over the world. Phylogenetic analysis revealed an extensive genetic heterogeneity among strains belonging to the same outbreak and revealed co‐circulation of sub‐genotype IA, IB, and the presence of IIIA sub‐genotype for the first time in a Mediterranean country. J. Med. Virol. 65:233–240, 2001. © 2001 Wiley‐Liss, Inc.
Complete genome analysis of enterovirus 71 isolated from an outbreak in Taiwan and rapid identification of enterovirus 71 and coxsackievirus A16 by RT‐PCR
Authors: Yan Jing‐Jou , Su Ih‐Jen , Chen Po‐Fu , Liu Ching‐Chuan , Yu Chun‐Keung , Wang Jen‐Ren
Published: August 2002

Hand, foot, and mouth disease (HFMD) and encephalomyelitis were two major clinical manifestations during the 1998 enterovirus 71 (EV71) epidemic in Taiwan. To investigate whether different clinical patterns were caused by alterations in EV71 genomes, the complete nucleotide sequences of four EV71 strains associated with HFMD or encephalomyelitis were compared. Among these viral strains, two or three nucleotide differences were found within the 5′‐noncoding region, and two or four amino acid differences were found within the regions encoding viral polyproteins; however, none of these differences were correlated with either clinical manifestation. Because coxsackievirus A16 was another major causative agent of HFMD, a reverse transcription‐polymerase chain reaction assay, with high sensitivity and specificity for identification of EV71 (both 100%) and coxsackievirus A16 (100 and 98.8%), was developed for the rapid differential identification of these two viruses in HFMD patients. J. Med. Virol. 65:331–339, 2001. © 2001 Wiley‐Liss, Inc.
Low prevalence of TT virus in the cerebrospinal fluid of viremic patients with central nervous system disorders
Authors: Maggi Fabrizio , Fornai Claudia , Vatteroni Maria Linda , Siciliano Gabriele , Menichetti Francesco , Tascini Carlo , Specter Steven , Pistello Mauro , Bendinelli Mauro
Published: August 2002

TT virus (TTV) is a widespread infectious agent of humans identified in 1998. In infected individuals, TTV induces persistent viremia but its life cycle and pathogenic potential are still poorly understood. In the present study, the presence of TTV DNA in 32 consecutive paired serum and cerebrospinal fluid (CSF) samples from patients with neurological (mainly multiple sclerosis) disorders was investigated by means of a sensitive quantitative real‐time PCR assay. Of the 24 patients who were found to carry TTV DNA in serum, 3 also had detectable TTV DNA in their CSF. Two TTV positive CSF samples had markers indicative of blood contamination or a disrupted blood‐brain barrier and contained considerably lower TTV loads as compared with the corresponding serum samples, thus suggesting that the virus they contained was of plasma origin. These findings indicated that in general TTV does not permeate effectively an intact blood‐brain barrier. Furthermore, the CNS does not represent a common site of TTV replication and persistence. However, at least one exception was observed: the third TTV positive CSF sample (obtained from a patient with subacute dementia of unknown origin) showed no markers suggestive of disrupted blood‐brain barrier or blood contamination and had a TTV DNA concentration similar to that found in the patient's serum. In addition, the TTV isolates detected in the two body fluids were distinct genetically. The detection of TTV DNA in CSF is of considerable interest but the clinical significance remains unknown. J. Med. Virol. 65:418–422, 2001. © 2001 Wiley‐Liss, Inc.
Inhibition of hepatitis C virus NS3 function by antisense oligodeoxynucleotides and protease inhibitor
Authors: Heintges Tobias , Encke Jens , zu Putlitz Jasper , Wands Jack R.
Published: August 2002

Hepatitis C Virus (HCV) NS3 protease is an attractive target for antiviral agent development because it is required for viral replication. Because a stable cell culture system or small animal model to study HCV replication is not readily available, we constructed an in vitro model allowing the investigation of NS3 transcription, translation, and protease function. Sequences encoding for full length HCV genomes were cloned and transfected into HuH‐7 human hepatocellular carcinoma cells to analyze NS3 transcription/translation. A plasmid pHCV ORF I luc that expresses the complete HCV coding region upstream of a luciferase reporter gene was designed to enable quantification of translated HCV proteins. Additionally, NS3 protease function was assessed by direct coexpression of NS3 and NS5 in HuH 7 cells, and the subsequent measurement of cleavage products. We found that antisense oligodeoxynucleotides (AS‐ODN) interfered with NS3 translation in a dose dependent fashion; AS‐ODN 5 cotransfection directed against NS3 sequences significantly inhibited protease activity as measured by cleaved NS5A levels. Finally, cleaved NS5A levels served as anindex of protease activity and Chymostatin, a protease inhibitor, almost completely blocked NS3 enzymatic activity. This cell culture system is useful in the assessment of potential antiviral agents on HCV NS3 expression and function. J. Med. Virol. 65:671–680, 2001. © 2001 Wiley‐Liss, Inc.
Clinical evaluation of a single oral dose of human‐bovine (UK) reassortant rotavirus vaccines Wa x UK (P1A[8],G6) and Wa x (DS‐1 x UK) (P1A[8],G2)
Authors: Eichelberger Maryna C. , Sperber Ellen , Wagner Mariam , Hoshino Yasutaka , Dudas Robert , Hodgins Vicki , Marron Jennifer , Nehring Pamela , Casey Roberta , Burns Barbara , Karron Ruth , Clements‐Mann Mary Lou , Kapikian Albert Z.
Published: August 2002

The safety, infectivity, and immunogenicity of two human‐bovine reassortant rotavirus candidate vaccines were evaluated in adults, children, and infants. One of these, Wa x UK, contained a single human rotavirus gene from the Wa strain that encoded VP4 P1A specificity in a background of 10 bovine genes including the VP7 gene that encodes G6 specificity, whereas the other, Wa x (DS‐1 x UK), possessed the human rotavirus VP4 gene from the Wa strain as well as the human VP7 gene from strain DS‐1 that encoded G2 specificity. Each of these vaccines appeared to be well‐tolerated and immunogenic in infants less than 6 months of age following a single oral dose, and therefore should be evaluated further as vaccine candidates. J. Med. Virol. 66:407‐416, 2002. © 2002 Wiley‐Liss, Inc.
Epstein‐Barr virus (EBV) DNA levels in palatine tonsils and autologous serum from EBV carriers
Authors: Nadal David , Blasius Martin , Niggli Felix K. , Meier Gabriela , Berger Christoph
Published: August 2002

A real‐time polymerase chain reaction was employed to detect and quantitate Epstein‐Barr virus (EBV) DNA in tonsils and autologous sera from EBV‐seropositive children. EBV DNA was found in 95% of tonsils from 21 children and in 50% from 18 children with serum IgG titers to the virus capsid antigen (VCA) of ≥1:160 and 1:10 to 1:80, respectively (P = 0.002). Tonsils from children with titers ≥1:160 harbored more EBV DNA copies per mg tissue (mean, 1,237; range, < 2–13,998) than from children with titers 1:10 to 1:80 (mean, 23; range, < 2–226; P < 0.0001). By contrast, EBV DNA was detected only in serum from 25% of 20 children with titers ≥ 1:160. Thus, ample differences in tonsillar EBV replication are mirrored inconstantly by detectable EBV in autologous serum suggesting that EBV DNA quantitation in tonsils may serve for refined monitoring of individuals at risk of EBV‐associated lymphoproliferation. J. Med. Virol. 67:54–58, 2002. © 2002 Wiley‐Liss, Inc.
Mother‐to‐infant transmission of hepatitis C virus: Rate of infection and assessment of viral load and IgM anti‐HCV as risk factors*
Authors: Dal Molin Gianna , D'Agaro Pierlanfranco , Ansaldi Filippo , Ciana Giovanni , Fertz Cristina , Alberico Salvatore , Campello Cesare
Published: August 2002

One hundred twenty‐six mother‐infant couples were studied and 105 exposed babies were monitored for at least 12 months to define the risk of mother‐to‐infant HCV transmission. Infection occurred in 5 out of 76 infants (6.6%) born to 69 viraemic mothers and in none of 29 born to 26 non‐viraemic mothers. Only one child was HCV RNA positive one month after birth, while the remaining children became positive at the 3rd to 4th month. HCV genotypes of the babies matched those of their mothers. No difference was found between women who transmitted the virus and those who did not with regard to age, history of drug abuse, HIV infection, ALT abnormal values, HCV genotype, type of delivery, and breast‐feeding. Four out of 5 infected infants were born to mothers with IgM anti‐HCV (P = 0.04). The mean viral titre in transmitting women (107.2) was higher than in non‐transmitting (106.5), and the proportion of mothers with viral load ≥ 107 was statistically higher in transmitting than non‐transmitting women (P = 0.03). These data show that HCV perinatal infection is a rare event and suggest that IgM positivity and high viral load (≥ 107) in the mother are independent variables correlated with HCV transmission (O.R. = 14.5; 95% CI: 1.3–160.7 and O.R. = 16.3; 95% CI: 1.5–179.9, respectively). J. Med. Virol. 67:137–142, 2002. © 2002 Wiley‐Liss, Inc.