bluuebunny/crossref_metadata_2025_split huggingface dataset:
Goitrogenic activity of p‐coumaric acid in rats
Authors: Khelifi‐Touhami Fatima , Taha Ragia A. , Badary Osama A. , Lezzar Alkassem , Hamada Farid M. A. 
Published: January 2004

AbstractThe effects of three natural phenolic acids (caffeic, ferulic, and p‐coumaric) on the rat thyroid gland were examined in a 3‐week oral‐treatment study. Forty male Wistar albino rats, divided into groups of 10 rats each and fed iodine‐rich diet, were administered by gastrointestinal tube saline (control), caffeic acid, ferulic acid, or p‐coumaric acid at a dose level of 0.25 μmol/kg/day for 3 weeks. The mean absolute and relative thyroid weights in caffeic, ferulic, or p‐coumaric acid groups were significantly increased to 127 and 132%, 146 and 153%, or 189 and 201% compared to control value, respectively. Histological examination of the thyroids of p‐coumaric acid group revealed marked hypertrophy and/or hyperplasia of the follicles. Caffeic or ferulic groups showed slight to moderate thyroid gland enlargement. Thyroid lesions in p‐coumaric acid group were associated with significant increases in cellular proliferation as indicated by [3H]thymidine incorporation. In addition, the goitrogenic effect of p‐coumaric acid was further confirmed by significant decreases (50%) in serum tri‐iodothyronine (T3) and thyroxine (T4), and a parallel increase (90%) in serum thyroid stimulating hormone (TSH) compared to control group. These results indicate that administration of p‐coumaric acid at relatively high doses induces goiter in rats. © 2003 Wiley Periodicals, Inc. J Biochem Mol Toxicol 17:324–328, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.10094
2′‐Deoxyadenosine causes apoptotic cell death in a human colon carcinoma cell line
Authors: Giannecchini Michela , D'Innocenzo Barbara , Pesi Rossana , Sgarrella Francesco , Iorio Mariacarla , Collecchi Paola , Tozzi Maria Grazia , Camici Marcella 
Published: January 2004

AbstractThe combination of 2′‐deoxyadenosine and 2′‐deoxycoformycin is toxic for the human colon carcinoma cell line LoVo. In this study we investigated the mode of action of the two compounds and have found that they promote apoptosis. The examination by fluorescence microscopy of the cells treated with the combination revealed the characteristic morphology associated with apoptosis, such as chromatin condensation and nuclear fragmentation. The occurrence of apoptosis was also confirmed by the release of cytochrome c and the proteolytic processing of procaspase‐3 in cells subjected to the treatment. To exert its triggering action on the apoptotic process, 2′‐deoxyadenosine enters the cells through an equilibrative nitrobenzyl‐thioinosine‐insensitive carrier, and must be phosphorylated by intracellular kinases. Indeed, in the present work we demonstrate by analysis of the intracellular metabolic derivatives of 2′‐deoxyadenosine that, as suggested by our previous findings, in the incubation performed with 2′‐deoxyadenosine and 2′‐deoxycoformycin, an appreciable amount of dATP was formed. Conversely, when also an inhibitor of adenosine kinase was added to the incubation mixture, dATP was not formed, and the toxic and apoptotic effect of the combination was completely reverted. © 2003 Wiley Periodicals, Inc. J Biochem Mol Toxicol 17:329–337, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.10095
The use of c‐src knockout mice for the identification of the main toxic signaling pathway of TCDD to Induce wasting syndrome
Authors: Vogel Christoph F. A. , Zhao Yeuchao , Wong Patrick , Young Naomi F. , Matsumura Fumio 
Published: January 2004

AbstractThe effect of single intraperitoneal injection of 115 μg/kg of TCDD (i.e., approximately 1/2 of LD50) to male C57BL/6 mice on the liver mRNA expression changes of several growth factor related genes was assessed at 3 h, 24 h, 10 days, and 30 days posttreatment. The results revealed that the most consistently elevated mRNAs during the entire test period were those of c‐Src, TGFα, and PDGFa. In contrast, those observed to be consistently suppressed were mRNAs for EGF receptor (EGFR), Ki‐Ras, SAPKK, Sp‐1, C/EBPβ, and NFkB. Elevation of mRNAs for TGFβ and STAT3 was observed only on day 10 and day 30. To assess the role of c‐Src in the above action of TCDD, we conducted a parallel study with congenic C57BL/6 male c‐src −/− mice. The results showed that in scr −/− mice the effect of TCDD was less in the case of mRNA expression of PDGFAA, STAT3, C/EPBβ, NMT‐1, and AP‐2γ in addition to c‐src as compared to scr +/+ mice. Those affected least by the absence of c‐Src were SAPKK, and surprisingly, EGF receptor mRNAs, both of which were consistently downregulated in both strains. In most of the other cases, the extent of TCDD‐induced changes were generally less pronounced in src −/− mice as compared to +/+ mice. These observations support the notion that c‐Src is an important mediator of the effects of TCDD on TGFα, PDGFAA, and C/EBPα, β. © 2003 Wiley Periodicals, Inc. J Biochem Mol Toxicol 17:305–315, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.10096
Purification and characterization of rat pancreatic fatty acid ethyl ester synthase and its structural and functional relationship to pancreatic cholesterol esterase
Authors: Kaphalia Bhupendra S. , Ansari G. A. S. 
Published: January 2004

AbstractFormation of fatty acid ethyl esters (FAEEs, catalyzed by FAEE synthase) has been implicated in the pathogenesis of chronic pancreatitis. In previous studies, we demonstrated that FAEE synthase, purified from rat liver microsomes, is identical to rat liver carboxylesterase (pI 6.1), and structurally and functionally different than that from pancreas. In this study, we purified and characterized rat pancreatic microsomal FAEE synthase, and determined its relationship with rat pancreatic cholesterol esterase (ChE). Since most of the serine esterases express p‐nitrophenyl acetate (PNPA)‐hydrolyzing activity as well as synthetic activity to form fatty acid esters or amides with a wide spectrum of alcohols and amines, respectively, we used PNPA‐hydrolyzing activity to monitor the purification of FAEE synthase during various chromatographic purification steps. Synthesizing activity towards FAEEs, fatty acid methyl esters, and fatty acid anilides was measured only in the pooled fractions. At each step of purification (ammonium sulfate saturation, Q Sepharose XL, and heparin‐agarose column chromatographies, and high performance liquid chromatography (anion exchange and gel filtration)) synthetic as well as hydrolytic activities copurified. Using ethanol, methanol, or aniline as substrates, the ester or anilide synthesizing activity of the purified protein was found to be 8709, 13000, and 2201 nmol/h/mg protein, respectively. The purified protein displayed a single band with an estimated molecular mass of ∼68 kD upon SDS‐PAGE under reduced denaturing conditions, cross‐reacted with antisera against rat pancreatic ChE and showed 100% N‐terminal sequence homology of the first 15 amino acids to that of rat pancreatic ChE. These results suggest that the purified protein has broad substrate specificity towards the conjugation of endogenous long chain fatty acids with substrates having hydroxyl and amino groups and is identical to ChE. © 2003 Wiley Periodicals, Inc. J Biochem Mol Toxicol 17:338–345, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.10097
Axial skeletal and hox expression domain alterations induced by retinoic acid, valproic acid, and bromoxynil during murine development
Authors: Kawanishi C. Y. , Hartig P. , Bobseine K. L. , Schmid J. , Cardon M. , Massenburg G. , Chernoff N. 
Published: January 2004

AbstractRetinoic acid (RA) alters the developmental fate of the axial skeletal anlagen. “Anteriorizations” or “posteriorizations,” the assumption of characteristics of embryonic areas normally anterior or posterior to the affected tissues, are correlated with altered embryonal expression domains of Hox genes after in utero RA treatment. These “homeotic” changes have been hypothesized to result from alterations of a “Hox cod” which imparts positional identity in the axial skeleton. To investigate whether such developmental alterations were specific to RA, or were a more general response to xenobiotic exposure, CD‐1 pregnant mice were exposed to RA, valproic acid (VA), or bromoxynil (Br) during organogenesis. Additionally, the expression domains of two Hox genes, Hoxa7 and Hoxa10, were examined in gestation day (GD) 12.5 embryos obtained from control, RA, VA, or Br, treated gravid dams exposed on GD 6, 7, or 8. The anterior expression boundary of Hoxa7 is at the level of the C7/T1 vertebrae and that of Hoxa10 is at L6/S1. Compound‐induced changes in the incidence of skeletal variants were observed. These included supernumerary cervical ribs (CSNR) lateral to C7, 8 vertebrosternal ribs, supernumerary lumbar ribs (LSNR) lateral to L1, extra presacral vertebrae, and the induction of vertebral and/or rib malformations. RA and VA administration on GD 6 caused posteriorization in the cervico‐thoracic region (CSNR) while GD 8 exposure to any of the three compounds resulted in anteriorizations in the thoraco‐lumbar area (LSNR and an increase in the number of presacral vertebrae). These effects occurred across regions of the axial skeleton. Analysis of gene expression demonstrated changes in the anterior boundaries of Hoxa7 expression domains in embryos treated on GD 6 and 8 with RA. VA and Br did not induce any statistically significant alterations in Hoxa7 and none of the compounds caused alterations in Hoxa10 expression domains. The studies indicate that RA GD 6 treatment‐induced Hoxa7 shifts were rostral (posteriorization) while the RA‐induced GD 8 anterior expression boundary shift was caudal (anteriorization), correlating with the axial skeletal changes noted. These data suggest that xenobiotic compounds such as VA and Br may induce similar axial skeletal changes by affecting different components of the developmental processes involved in the patterning of the axial skeleton. © 2003 Wiley Periodicals, Inc. J Biochem Mol Toxicol 17:346–356, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.10098
Vanadium inhibits placental glutathione S‐transferase (GST‐P) positive foci in 1,2‐dimethyl hydrazine induced rat colon carcinogenesis
Authors: Kanna P. Suresh , Mahendrakumar C. B. , Chatterjee M. , Hemalatha P. , Datta Subroto , Chakraborty Prabir 
Published: January 2004

AbstractVanadium (V) has recently been found to possess potent anti‐neoplastic activity in rat colon carcinogenesis. In the present study attempts have been made to investigate the expression of the number and area of aberrant crypt foci positive for placental glutathione S‐transferase (GST‐P) during 1,2‐dimethyl hydrazine (DMH)‐induced rat colon carcinogenesis. Male Sprague Dawley rats were randomly divided into four groups. Rats in group A were designed as normal controls. Group B animals received DMH once a week (20 mg/kg body wt.) intraperitoneally for 16 weeks. Group C rats received the same treatment of DMH as in group B, along with 0.5‐ppm vanadium as ammonium monovanadate ad libitum in drinking water throughout the experiment. Vanadium alone was given to Group D rats without any DMH injection. The expression of the number and the area of aberrant crypt foci (ACF) positive for GST‐P was maximum in DMH‐treated group. Vanadium‐treated rats significantly reduced (P < 0.001) the expression of GST‐P positive ACF cells (by 71.13%) for the entire period of the study. Moreover the histopathological examination also showed that vanadium action could minimize the aberrant crypt foci (P < 0.001). Furthermore, vanadium supplementation also elevated SOD activities in both liver and colon (P < 0.01, P < 0.02 and P < 0.01, P < 0.02 respectively) when compared to their carcinogen counterparts. Our results confirm that vanadium is particularly effective in limiting the action of the carcinogen, thereby establishing its anticarcinogenicity in chemically induced rat colon carcinogenesis. © 2003 Wiley Periodicals, Inc. J Biochem Mol Toxicol 17:357–365, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.10099
Garlic attenuates chrysotile‐mediated pulmonary toxicity in rats by altering the phase I and phase II drug metabolizing enzyme system
Authors: Ameen Mohamed , Musthapa M. Syed , Abidi Parveen , Ahmad Iqbal , Rahman Qamar 
Published: January 2004

AbstractAsbestos and its carcinogenic properties have been extensively documented. Asbestos exposure induces diverse cellular events associated with lung injury. Previously, we have shown that treatment with chrysotile shows significant alteration in phase I and phase II drug metabolizing enzyme system. In this study we have examined some potential mechanisms by which garlic treatment attenuates chrysotile‐mediated pulmonary toxicity in rat. Female Wistar rats received an intratracheal instillation of 5 mg chrysotile (0.5 mL saline) as well as intragastric garlic treatment (1% body weight (v/w); 6 days per week). Effect of garlic treatment was evaluated after 1, 15, 30, 90, and 180 days by assaying aryl hydrocarbon hydroxylase (AHH), glutathione (GSH), glutathione S‐transferase (GST), and production of thiobarbituric acid reactive substances (TBARS) in rat lung microsome. The results showed that AHH and TBARS formation were significantly reduced at day 90 and day 180 in chrysotile treated garlic cofed rats; GSH recovered 15 days later to the near normal level and GST elevated significantly after treatment of garlic as compared to chrysotile alone treated rat lung microsome. The data obtained shows that inhibition of AHH activity and induction of GST activity could be contributing factor in chrysotile‐mediated pulmonary toxicity in garlic cofed rats. However, recovery of GSH and inhibition of TBARS formation by garlic and its constituent(s) showed that garlic may give protection by altering the drug metabolizing enzyme system. © 2003 Wiley Periodicals, Inc. J Biochem Mol Toxicol 17:366–371, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.10100
An electron microscopic and biochemical study of the effects of glucagon on glycogen autophagy in the liver and heart of newborn rats
Authors: Kondomerkos D.J. , Kalamidas S.A. , Kotoulas O.B. 
Published: January 2004

AbstractThe effects of glucagon on the ultrastructural appearance and acid glucosidase activities in the liver and heart of newborn rats were studied. Liver or heart glycogen‐hydrolyzing activity of acid glucosidase increased 3 hours after birth and gradually decreased from 3 to 9 hours. Maltose‐hydrolyzing activity of acid glucosidase also rose 3 hours after birth, maintained a plateau between 3 and 6 hours, and fell at 9 hours. The administration of glucagon increased autophagic activity in the hepatocytes at the age of 6 hours. Glycogen inside the autophagic vacuoles was decreased, apparently due to the increased glycogen degradation. Glycogen‐hydrolyzing activity was elevated in both the liver and the heart. Maltose‐hydrolyzing activity was elevated in the liver, but not in the heart. The results of this study suggest that the glycogen‐hydrolyzing and maltose‐hydrolyzing activities of acid glucosidase are due to different enzymes. Glucagon's effect on the glycogen‐hydrolyzing acid glucosidase activity and autophagosomal morphology is similar in both the liver and the heart. Microsc. Res. Tech. 63:87–93, 2004. © 2004 Wiley‐Liss, Inc.
The transillumination possibility of imidazole‐osmium postfixed muscle tissue and its consequences for the handling of muscle tissue samples
Authors: Voigt Tilman , Dauber Wolfgang 
Published: January 2004

AbstractThe osmium postfixation of tissue leads to good results for transmission electron microscopy, but also produces completely blackened tissue samples that do not allow the recognition of internal structures. With imidazole‐osmium postfixation, one achieves comparable results in high electron microscopic resolution as with routine osmium postfixation. But the tissue samples are not blackened and can, therefore, be transilluminated with point light sources. The new postfixation technique makes it possible to recognize histological details such as vessels, nerve fibers, and the cross‐banding pattern in an untrimmed block. This makes it possible to screen‐embedded tissue samples for appropriate ultrastructural processing. Microsc. Res. Tech. 63:129–132, 2004. © 2004 Wiley‐Liss, Inc.
Moduli for equivariant vector bundles of rank two on smooth toric surfaces
Authors: Perling Markus 
Published: January 2004

AbstractWe give a complete classification of equivariant vector bundles of rank two over smooth complete toric surfaces and construct moduli spaces of such bundles. This note is a direct continuation of an earlier note where we developed a general description of equivariant sheaves on toric varieties. Here we give a first application of that description. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Rank two vector bundles with canonical determinant
Authors: Teixidor i Bigas Montserrat 
Published: January 2004

AbstractDenote by Bk2,K the locus of vector bundles of rank two that have canonical determinant and at least k sections. We show that for a generic curve of genus g,Bk2,K is non‐empty and has a component of the expected dimension if g is sufficiently large. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Querschnittseinfluss beim Zugversuch von siliziertem kohlenstoffkurzfaserverstärktem Kohlenstoff (C/C‐SiC)
Authors: Henrich M. , Regener D. , Weiß R. 
Published: January 2004

AbstractDie Untersuchung befasst sich mit der mechanischen Prüfung einer kohlenstoffkurzfaserverstärkten Keramik. Für diese Werkstoffgruppe, die in einigen Anwendungen bereits erfolgreich eingesetzt wird, liegen bisher noch keine gültigen Prüfvorschriften vor. Dies ist auch ein Grund dafür, dass Hersteller und Institute Prüfnormen für monolithische Werkstoffe oder Verbundwerkstoffe heranziehen, wobei unabhängig von diesen Normen Probenquerschnitte und Prüfvolumen frei gewählt oder basierend auf einer Prüfnorm mit einem Faktor vergrößert werden. Diese Vorgehensweise kann zu einer Fehlinterpretation führen.Aufgrund der großen Bandbreite von verschiedensten Faserkeramiken soll in dieser Arbeit der Querschnittseinfluss im Zugversuch exemplarisch nur an einem silizierten kohlenstoffkurzfaserverstärkten Kohlenstoff der Firma Schunk Kohlenstofftechnik mit der Bezeichnung FU2952/1P77 untersucht werden. Zur Klärung der Untersuchungsergebnisse werden neben Schliffbildern mit der Auflichttechnik Bruchflächen im Rasterelektronenmikroskop (REM) analysiert.
Loading state in spot‐like overlap joints determined by correlation of deformation patterns
Authors: Radaj D. , Stoppler W. 
Published: January 2004

AbstractThe loading state in spot‐like overlap joints (spot‐welded, clinched, riveted, bolted or others) can be determined by evaluating measured surface strains around the local joint (e.g. a weld spot). The measured strain pattern is decomposed into proportions of reference patterns representing simple basic loading states. Correlation analysis on the basis of Markov chains is used to achieve this.
The classical limit of the relativistic Vlasov–Maxwell system in two space dimensions
Authors: Lee Hayoung 
Published: January 2004

AbstractThe motion of a collisionless plasma is modelled by the Vlasov–Maxwell system. In this paper, solutions of the relativistic Vlasov–Maxwell system are considered in two space dimensions. The speed of light, c, appears as a parameter in the system. With representations of the electric and magnetic fields, conditions are established under which solutions of the relativistic Vlasov–Maxwell system converge pointwise to solutions of the non‐relativistic Vlasov–Poisson system as c tends to infinity, at the asymptotic rate of 1/c. Copyright © 2004 John Wiley & Sons, Ltd.
Optical Fourier and Hartley transform adaptive filters
Authors: Abushagur Mustafa A. G. , Berinato Robert J. 
Published: January 2004

AbstractOptical signal‐processing architectures are presented to realize frequency‐domain implementations of the classical least‐mean‐square (LMS) adaptive‐filtering algorithm. Optical implementation of both Fourier and Hartley transforms are considered. Performance assessments of the digital and optical approaches based on computer simulation and computational complexity are presented. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 40: 280–285, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11352
A new hybrid‐ring geometry well suited for CAD implementation
Authors: Olszewska Joanna , Vaccaro Stefano , Zürcher Jean‐François , Skrivervik Anja K. 
Published: January 2004

AbstractThis paper presents a new hybrid‐ring geometry, that can be synthesized easily and quickly with a computer tool and realized without difficulty in microstrip technology. The presented geometry performances are tested by simulations and measurements of some microstrip devices. Very good agreement between obtained and predicted results is observed. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 40: 285–287, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11353
A compact ultrawideband triangular patch antenna
Authors: Lepage A. C. , Begaud X. 
Published: January 2004

AbstractThe characteristics of an F‐shaped‐probe feeding a triangular patch antenna with a small‐size ground plane have been simulated and measured. A −10‐dB impedance bandwidth of 47% and an average gain of 6.4 dBi have been achieved. The phase of the far‐field over the bandwidth has been studied to analyze the distortion induced by the antenna on an ultra‐wideband (UWB) pulse signal. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 40: 287–289, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11354
Wideband 2 × 2 sequentially rotated patch antenna array with a series feed
Authors: Evans H. , Sambell A. 
Published: January 2004

AbstractA new wideband 2 × 2 patch antenna array operating at 5.8 GHz with an out‐of‐line series feed is presented. Input impedance bandwidth and axial ratio bandwidth are shown to be significantly increased for this new array, which employs a sequential rotation of series‐fed, circularly polarised, aperture‐coupled radiating elements. The array also maximises the available space on the feed substrate for microwave circuitry. A VSWR 2:1 bandwidth of 22.8% and a 3‐dB axial ratio of 17.5% are confirmed by full‐wave simulation and experimental measurement. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 40: 292–294, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11356
On pattern stability of the crossed planar monopole
Authors: Ammann M. J. , Cordoba R. Sierra , Uzelac M. , Evans J. A. , Schwarzbacher A. T. 
Published: January 2004

AbstractIt is shown that a significant improvement in the radiation pattern stability with frequency can be achieved for the wideband planar monopole antenna. This is realised by the addition of a second orthogonal element, while maintaining the same overall surface area. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 40: 294–296, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11357