bluuebunny/crossref_metadata_2025_split huggingface dataset:
Transcription factors C/EBP‐β and ‐δ regulate IL‐6 production in IL‐1β‐stimulated human enterocytes
Authors: Hungness Eric S. , Luo Guang‐ju , Pritts Timothy A. , Sun Xiaoyan , Robb Bruce W. , Hershko Dan , Hasselgren Per‐Olof 
Published: October 2002

AbstractIn recent studies, treatment with IL‐1β of cultured Caco‐2 cells, a human intestinal epithelial cell line, resulted in transcriptional upregulation of IL‐6 production. The role of C/EBP‐β and ‐δ in enterocyte IL‐6 production is not known. Stimulation with IL‐1β of Caco‐2 cells transiently transfected with a luciferase reporter plasmid containing a wild‐type IL‐6 promoter resulted in an approximately 3.5‐fold increase in luciferase activity. This effect of IL‐1β was reduced by approximately 30% when the C/EBP binding site in the IL‐6 promoter was mutated, supporting a role of C/EBP in the regulation of IL‐6 production. When Caco‐2 cells were treated with IL‐1β in the presence of the MAPK inhibitor, PD‐98059, IL‐6 mRNA and protein levels were reduced by the same concentrations of PD‐98059 that inhibited C/EBP DNA binding activity in previous studies. Finally, overexpression of C/EBP‐β and ‐δ in IL‐1β‐treated Caco‐2 cells resulted in a 10–12‐fold increase in IL‐6 production. The results suggest that the β and δ isoforms of the C/EBP family of transcription factors at least in part regulate IL‐6 production in human intestinal epithelial cells. © 2002 Wiley‐Liss, Inc.
Transient and sustained ERK phosphorylation and nuclear translocation in growth control
Authors: Adachi Takahito , Kar Siddhartha , Wang Meifang , Carr Brian I. 
Published: October 2002

AbstractGrowth stimulation and inhibition are both associated with tyrosine phosphorylation. We examined the effects of epidermal growth factor (EGF), a growth stimulant, and compound 5 (Cpd 5), a protein‐tyrosine phosphatase (PTPase) inhibitor, which inhibits the growth of the same Hep3B hepatoma cells. We found that both EGF and Cpd 5 induced tyrosine phosphorylation of EGF receptor (EGFR) and ERK. However, the phosphorylation caused by EGF was transient and that caused by Cpd 5 was prolonged. Furthermore, Cpd 5 action caused a strong nuclear phospho‐ERK signal and induced phospho‐Elk‐1, a nuclear target of ERK activation, in contrast to the weak effects of EGF. An ERK kinase assay demonstrated that ERK activated by Cpd 5 could phosphorylate its physiological substrate, Elk‐1. The MEK inhibitors PD098056 and U0126 abrogated both the induction by Cpd 5 of phospho‐ERK, its nuclear translocation and phospho‐Elk‐1 and also antagonized its growth inhibitory effects. Furthermore, phospho‐ERK phosphatase and phospho‐Elk‐1 activities were lost from nuclear extracts from Cpd 5 treated, but not EGF treated cells. In conclusion, the data show that Cpd 5 causes growth inhibition as a consequence of prolonged ERK and Elk‐1 phosphorylation, likely a result of inhibition of multiple PTPases, including those acting on phospho‐EGFR, on phospho‐ERK, and on phospho‐Elk‐1, in contrast to the kinase driven transient activation resulting from EGF. © 2002 Wiley‐Liss, Inc.
Stress kinase p38 mediates EGFR transactivation by hyperosmolar concentrations of sorbitol
Authors: Cheng Hao , Kartenbeck Jürgen , Kabsch Kirsten , Mao Xiahong , Marqués Margarita , Alonso Angel 
Published: October 2002

AbstractActivation of the epidermal growth factor receptor (EGFR) has been shown to occur by ligand‐dependent and ligand‐independent mechanisms. Different molecular mechanisms have been found to be responsible for ligand‐independent receptor transactivation. Here, we show that hyperosmolar concentrations of sorbitol activate the EGFR in human keratinocytes. Experiments using specific inhibitors of EGFR phosphorylation show that the increased amount of activated receptors is the result of a decreased rate of dephosphorylation. Furthermore, sorbitol treatment results in a strong activation of stress kinase p38. Treatment of the cells with SB203580, a known inhibitor of p38 α and β kinases, results in impairment of receptor activation, indicating that the stress kinase is involved in receptor activation modulation. This is further reinforced by experiments showing that addition of Toxin B, known to be an inhibitor of the small Rho GTPases rac1, cdc42, and Rho A/B, to the cells results in a strong induction of EGFR activation. Our results point, therefore, to a mechanism by which osmotic shock activates EGFR through the small Rho GTPases‐p38 stress kinase pathway. © 2002 Wiley‐Liss, Inc.
Sonographic evaluation of mammographically detected microcalcifications without a mass prior to stereotactic core needle biopsy
Authors: Cheung Yun‐Chung , Wan Yung‐Liang , Chen Shih‐Cheh , Lui Kar‐Wai , Ng Shu‐Hang , Yeow Kee‐Min , Lee Kam‐Fai , Hsueh Swei 
Published: October 2002

AbstractPurpose.The purpose of this prospective study was to evaluate the clinical usefulness of sonographically re‐evaluating areas of microcalcification found mammographically before undertaking stereotactic core needle biopsy (SCNB).Methods.Patients with nonpalpable breast lesions appearing as microcalcifications on mammograms and who had been referred to us for SCNB were re‐evaluated sonographically before the procedure. None of the breast lesions had been associated with a density on the mammograms, and the initial sonographic evaluations had been negative. Using the mammograms for correlation, we meticulously re‐evaluated the areas of microcalcifications sonographically using a high‐frequency linear‐array transducer. The sonographic and histopathologic results were then reviewed and correlated. The sonographic findings and visibility of the mammographically detected microcalcifications were analyzed by the 2‐tailed Fisher's exact test and the chi‐square test.Results.Sixty‐six patients, who had 68 cases of microcalcifications, were enrolled. Thirteen of the 66 patients underwent surgery, and 9 of the 13 were found to have breast carcinoma. In the sonographic re‐evaluation before SCNB in these 9 patients, an associated soft tissue mass was demonstrated in 5 patients but not in the other 4. Sonographic re‐evaluation also revealed abnormalities in 24 of 68 cases (35.3%), in contrast to the negative findings on the initial sonography. Using the chi‐square test to identify a trend, we found that the percentage of cases that were sonographically visible was highest for clustered benign microcalcifications and lowest for segmental benign microcalcifications (p < 0.0001).Conclusions.In breast lesions that appear as microcalcifications without an associated mass on mammograms, pre‐SCNB sonographic re‐evaluation with a high‐frequency transducer can depict microcalcifications, particularly the clustered ones, and can detect small associated masses. Although the absence of a sonographically detectable mass in areas of mammographically detected microcalcifications does not guarantee the absence of cancer, the presence of an associated mass on sonography should warrant close follow‐up in the case of negative results to avoid a delay in the diagnosis of breast carcinoma. © 2002 Wiley Periodicals, Inc. J Clin Ultrasound 30:323–331, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI: 10.1002/jcu.10074
Metastasis of primitive neuroectodermal tumor to the breast
Authors: Kwak Jin‐Young , Kim Eun‐Kyung , You Jai Kyung , Oh Ki Keun , Hong Soon Won , Kim Se Hoon 
Published: October 2002

AbstractWe performed mammography and sonography on a 49‐year‐old woman who had a mass in her left axilla that had been present for 1 month and who had undergone excision of a primitive neuroectodermal tumor (PNET) on her back 1 year before. Mammography revealed 2 adjacent, dense nodules in the left breast and enlarged lymph nodes, without a fatty hilum or internal microcalcifications, in the left axilla. Sonography showed 2 round to oval, markedly hypoechoic nodules in the left breast and enlarged, markedly hypoechoic lymph nodes, without microcalcifications, in the left axilla. We then performed sonographically guided core biopsy. Histopathologic analysis of the specimens confirmed the presence of PNET in the left breast and axillary lymph nodes. The patient was then treated with chemotherapy. To our knowledge, this report is the first to describe radiologic findings of metastasis of PNET to the breast. © 2002 Wiley Periodicals, Inc. J Clin Ultrasound 30:374–377, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI: 10.1002/jcu.10076
Pituitary adenylate cyclase‐activating polypeptide induces testicular testosterone synthesis through PGE2 mediation in crested newt, Triturus carnifex
Authors: GOBBETTI ANNA , ZERANI MASSIMO 
Published: October 2002

AbstractThe aim of the present work was to study the possible role of adenylate cyclase‐activating polypeptide (PACAP) 38 in the testicular intracellular mechanism regulating steroidogenesis of crested newt, Triturus carnifex. Gonads were incubated in vitro with PACAP 38 and prostaglandin (PG) E2 alone or with inhibitors of cyclooxygenase (COX), adenylate cyclase (AC), and phospholipase C (PLC) for 30 min and 60 min. PGE2, PGF2α, testosterone, and estradiol‐17β were measured in the culture medium; aromatase (AR) activity and cAMP were assessed in the tissue. PACAP 38 increased PGE2 (30 min and 60 min), estradiol‐17β (60 min), cAMP (60 min), and AR (60 min) but decreased testosterone (60 min). PGE2 increased estradiol‐17β, cAMP, and AR and decreased testosterone at 30 and 60 min.PLC inhibitor counteracted the effects of PACAP 38, while AC inhibitor counteracted these effects except for PGE2 increase. AC inhibitor counteracted the effects of PGE2, while PLC did not. COX inhibitor decreased PGF2α (30 min and 60 min), PGE2 (30 min and 60 min), estradiol‐17β (60 min), cAMP (60 min), and AR (60 min), but increased testosterone (60 min). These in vitro results suggest that, in newt testis, PACAP 38 acts on PLC, inducing the increase of PGE2 which, in turn, acting on AC, increases AR activity with the consequent estradiol‐17β increase and testosterone decrease. © 2002 Wiley‐Liss, Inc.
Immunocytochemical analysis of beta (β) keratins in the epidermis of chelonians, lepidosaurians, and archosaurians
Authors: ALIBARDI LORENZO , SAWYER ROGER H. 
Published: October 2002

AbstractBeta (β) keratins are present only in the avian and reptilian epidermises. Although much is known about the biochemistry and molecular biology of the β keratins in birds, little is known for reptiles. In this study we have examined the distribution of β keratins in the adult epidermis of turtle, lizard, snake, tuatara, and alligator using light and electron immunocytochemistry with a well‐characterized antiserum (anti‐β1 antiserum) made against a known avian scale type β keratin. In lizard, snake, and tuatara epidermis this antiserum reacts strongly with the beta‐layer, more weakly with the oberhautchen before it merges with the beta‐layer, and least intensely with the mesos layer. In addition, the anti‐β1 antiserum reacts specifically with the setae of climbing pads in gekos, the plastron and carapace of turtles, and the stratum corneum of alligator epidermis. Electron microscopic studies confirm that the reaction of the anti‐β1 antiserum is exclusively with characteristic bundles of the 3‐nm β keratin filaments in the cells of the forming beta‐layer, and with the densely packed electron‐lucent areas of β keratin in the mature bet‐ layer. These immunocytochemical results suggest that the 3‐nm β keratin filaments of the reptilian integument are phylogenetically related to those found in avian epidermal appendages. © 2002 Wiley‐Liss, Inc.
Growth and the poor: a comment on Dollar and Kraay
Authors: Lübker Malte , Smith Graham , Weeks John 
Published: October 2002

AbstractIn a recent paper Dollar and Kraay come to sweeping conclusions about economic growth and the poor. On the basis of empirical work they assert that standard World Bank and IMF policy packages are good for the poor. This paper demonstrates that (i) the empirical work is based on theoretically unsound equations; (ii) the data are seriously flawed; and (iii) the policy variables are not defined appropriately, nor are they tested in a consistent manner. These problems imply that the policy conclusions of the authors are unsafe. Copyright © 2002 John Wiley & Sons, Ltd.
Stereoselective synthesis of L‐[2,3,4,5‐D4] ornithine
Authors: Oba Makoto , Ishihara Teruaki , Satake Hiromi , Nishiyama Kozaburo 
Published: October 2002

AbstractSynthesis of L‐[2,3,4,5‐D4]ornithine in which all of the diastereotopic hydrogens were stereoselectively labeled with deuterium was investigated. The chirally deuterated 3‐aminopropanal derivative, a key intermediate in this synthesis, was prepared by a catalytic deuteration of an unsaturated γ‐lactone derived for L‐glutamic acid followed by several functional group interconversions. Condensation of the obtained deuterium‐labeled 3‐aminopropanal derivative with a chiral glycine template afforded unsaturated ornithine. The dehydroornithine was then subjected to a catalytic deuteration followed by deprotection to give the L‐[2,3,4,5‐D4]ornithine. Copyright © 2002 John Wiley & Sons, Ltd.
Ultrastructure of spermatozoa of the lizard Ameiva ameiva, with considerations on polymorphism within the family Teiidae (Squamata)
Authors: Giugliano L.G. , Teixeira R.D. , Colli G.R. , Báo S.N. 
Published: October 2002

AbstractA detailed description of sperm ultrastructure of the lizard Ameiva ameiva (Teiidae) is provided. Mature spermatozoa are characterized by: a depressed acrosome at the anterior portion; a unilateral ridge at the anterolateral portion; an acrosome vesicle divided into cortex and medulla; medulla divided into two regions with different electron‐densities; paracrystalline subacrosomal material with radial organization in transverse section; a pointed prenuclear perforatorium; a stopper‐like perforatorium base plate that appears embedded in the subacrosomal material; the presence of an epinuclear lucent zone surrounded by its own membrane; a large nuclear rostrum; round nuclear shoulders; a nuclear space at the nucleus tip; a bilateral stratified laminar structure; a central dense body within the proximal centriole; a short midpiece; an axonemal midpiece axial component; peripheral fibers 3 and 8 grossly enlarged at the anterior portion of axoneme; columnar mitochondria with linear cristae; solid dense bodies arranged as rings or spirals; a triangular‐shaped annulus in transverse section; a fibrous sheath into the midpiece; a thin zone of cytoplasm at the anterior portion of the principal piece; and a slight decrease in diameter of the principal piece immediately after the annulus. Comparisons with Cnemidophorus sexlineatus and Micrablepharus maximiliani failed to identify unique sperm ultrastructure traits of Teiidae or Teiioidea (Teiidae + Gymnophthalmidae). High levels of polymorphism between Ameiva and Cnemidophorus, two closely related genera of the family Teiidae, were detected, suggesting that extensive sampling within squamate families is essential if sperm ultrastructure data are to be used in phylogenetic analyses at this taxonomic level. J. Morphol. 253:264–271, 2002. © 2002 Wiley‐Liss, Inc.
Axillary lymph node metastases: A statistical analysis of various parameters in MRI with USPIO
Authors: Stets Constanze , Brandt Silvio , Wallis Fintan , Buchmann Jörg , Gilbert F.J. , Heywang‐Köbrunner Sylvia H. 
Published: October 2002

AbstractPurposeTo assess the value of plain vs. iron oxide‐enhanced MRI vs. the combined study (plain + postcontrast) based on qualitative and quantitative parameters of three pulse sequences.Materials and MethodsData from two sites were acquired using the same technique; therefore, this data could be pooled. T1W‐SE, T2W‐FSE, and 3D‐PSIF were used before and 24–36 hours after MRI with ultra small particles of iron oxide (USPIO) was performed. A total of 52 lymph nodes (LNs) in nine patients (25 benign, 27 malignant) were evaluated by two readers who were visually and quantitatively blinded to the histology. Combinations of the following diagnostic parameters were compared using logistic regression analysis: the short‐axis diameter of the LN, the signal distribution of the LN on postcontrast agent MRI (homogeneous or heterogeneous), and qualitatively and quantitatively determined signal changes of the LN following administration of contrast agent in the three evaluated sequences.ResultsUsing pre‐ and postcontrast data, the optimized accuracy based on the statistically most significant parameters (LN diameter > 6 mm, visual assessment of signal change on T2W‐SE) was 87% (81% sensitivity, 92% specificity). Precontrast data alone yielded 75% accuracy (63% sensitivity, 86% specificity). Postcontrast data alone yielded 75% accuracy (56% sensitivity, 96% specificity).ConclusionBased on our results, USPIO‐MRI improved the diagnosis of metastatic axillary LNs compared with precontrast MRI alone. Both pre‐ and postcontrast studies are needed. T1W‐SE and T2W‐PSIF did not yield significant additional information. This study may help to further improve the technique of USPIO imaging. J. Magn. Reson. Imaging 2002;16:60–68. © 2002 Wiley‐Liss, Inc.
Imaging inflammation: Direct visualization of perivascular cuffing in EAE by magnetic resonance microscopy
Authors: Gareau Paula J. , Wymore Allison C. , Cofer Gary P. , Johnson G. Allan 
Published: October 2002

AbstractPurposeTo determine if the architectural features revealed by magnetic resonance microscopy (MRM) allow one to detect microscopic abnormalities associated with neuroinflammation in fixed brain sections from animals with experimental allergic encephalomyelitis (EAE), an animal model for multiple sclerosis (MS).Materials and MethodsImaging was performed at the Center for In Vivo Microscopy (CIVM) using a 9.4‐Tesla, 89‐mm bore, superconducting magnet with actively shielded gradients capable of 850 mT/m. A number of MR contrasts and spatial resolutions were explored.ResultsThe assessment of EAE brain showed that it is possible to visualize perivascular cuffing in vitro by MRM on three‐dimensional T1 proton stains.ConclusionInflammatory cell infiltration is a prerequisite for the development of lesions in EAE and MS. Thus, the ability to directly detect individual perivascular cuffs of inflammation may provide a useful means of monitoring the time course of inflammatory events, as conventional histopathological scoring of perivascular cuffs is utilized, but in the absence of sectioning and staining. J. Magn. Reson. Imaging 2002;16:28–36. © 2002 Wiley‐Liss, Inc.
Sequential diffusion‐weighted magnetic resonance imaging study of lysophosphatidyl choline‐induced experimental demyelinating lesion: An animal model of multiple sclerosis
Authors: Degaonkar Mahaveer N. , Jayasundar Rama , Jagannathan Naranamangalam R. 
Published: October 2002

AbstractPurposeTo differentiate the surrounding edema from the focal demyelinating lesion during the early phase of the lesion using an apparent diffusion coefficient (ADC), and to monitor the changes in ADCs during the complete progression of a lysophosphatidyl choline (LPC)‐induced experimental demyelinating lesion, an animal model of multiple sclerosis (MS).Material and MethodsEighteen rats divided into two groups—demyelinating lesion (group I, N = 12) and vehicle group (saline injected; group II, N = 6)—were studied. A 0.2‐μl quantity of 1% LPC solution in isotonic saline was injected in the rat brain internal capsule (IC) area to create the demyelinating lesion. Six rats were used exclusively for histology. Diffusion‐weighted (DW) images were acquired at different diffusion weightings on the 3rd, 5th, 10th, 15th, and 20th days after LPC injection. ADC was measured from three regions of interest (ROIs) within the IC: focal demyelinating lesion (area A), surrounding area of the lesion (area B), and contralateral IC area (area C).ResultsHistology revealed demyelination of the IC area during the early phase of lesion progression up to day 10 and remyelination thereafter. Elevated ADCs were observed for the surrounding edematous area (area B), compared to the focal demyelinating lesion (area A) during the early phase of the demyelination process, while substantial reduction of ADCs was noticed during remyelination for both regions.ConclusionMeasurement of ADC showed clear differentiation of the surrounding edema from the LPC‐induced focal demyelinating lesion in rats, especially during the early phase of the lesion progression. J. Magn. Reson. Imaging 2002;16:153–159. © 2002 Wiley‐Liss, Inc.
Evaluation of a new ultrasmall superparamagnetic iron oxide contrast agent Clariscan®, (NC100150) for MRI of renal perfusion: Experimental study in an animal model
Authors: Bachmann Rainald , Conrad Rudolf , Kreft Burkhard , Luzar Oliver , Block Wolfgang , Flacke Sebastian , Pauleit Dirk , Träber Frank , Gieseke Jürgen , Saebo Karin , Schild Hans 
Published: October 2002

AbstractPurposeTo determine the diagnostic value of a new ultrasmall superparamagnetic iron oxide Clariscan®, (NC100150) for the evaluation of renal perfusion in an animal model using a 3D‐FFE‐EPI sequence.Materials and MethodsFour groups of four rabbits each were imaged after bolus injection of NC100150, using a 1.5 T MR system (Gyroscan ACS‐NT). T2*w MR images in the coronal plane were acquired over 60 seconds with an echo‐shifted 3D‐FFE‐EPI sequence (TR/TE/α = 18/25 msec/8°). Data were transferred to a workstation and converted into concentration curves. Based on the fitted concentration time curves, parameter maps were calculated pixelwise: bolus arrival time (T0), time‐to‐peak (TTP), mean transit time (MTT), and relative bolus volume (rBV). Maximum signal decrease was determined with respect to the baseline value.ResultsMean MTT increased from 4.2 seconds at a dose of 0.25 mg to 5.9 seconds at 1.0 mg (P < .0001). The maximum signal decrease was observed at 0.75 mg, corresponding to 85% of the baseline value. Transit times of the contrast bolus were accurately calculated for the cortex and the outer medulla, but at the level of the inner medulla no arterial flow profile was identified. No significant difference between the cortex and the outer medulla was found for either T0 or rBV, but medullar TTP and MTT were prolonged with regard to cortical TTP and MTT (6.3 seconds vs. 5.7 seconds, P < .001; 5.7 seconds vs. 4.2 seconds, P < .0001).ConclusionThe employed intravascular contrast agent is well suited to assess renal perfusion. By the use of a T2*w3D perfusion sequence, cortical and medullar transit times can be quantified and physiologic information on regional perfusion differences can be obtained. J. Magn. Reson. Imaging 2002;16:190–195. © 2002 Wiley‐Liss, Inc.