bluuebunny/crossref_metadata_2025 huggingface dataset:
Retinoic Acid-Induced Stimulation of Sodium Iodide Symporter Expression and Cytotoxicity of Radioiodine in Prostate Cancer Cells
Authors: Spitzweg C. , Scholz I. V. , Bergert E. R. , Tindall D. J. , Young C. Y. F. , Göke B. , Morris J. C.
Published: April 2003

We reported recently the induction of androgen-dependent iodide uptake activity in the human prostatic adenocarcinoma cell line LNCaP using a prostate-specific antigen (PSA) promoter-directed expression of the sodium iodide symporter (NIS) gene. This offers the potential to treat prostate cancer with radioiodine. In the current study, we examined the regulation of PSA promoter-directed NIS expression and therapeutic effectiveness of 131I in LNCaP cells by all-trans-retinoic acid (atRA). For this purpose, NIS mRNA and protein expression levels in the NIS-transfected LNCaP cell line NP-1 were examined by Northern and Western blot analysis following incubation with atRA (10 −9 to 10−6m) in the presence of 10−9m mibolerone (mib). In addition, NIS functional activity was measured by iodide uptake assay, and in vitro cytotoxicity of 131I was examined by in vitro clonogenic assay. Following incubation with atRA, NIS mRNA levels in NP-1 cells were stimulated 3-fold in a concentration-dependent manner, whereas NIS protein levels increased 2.3-fold and iodide accumulation was stimulated 1.45-fold. This stimulatory effect of atRA, which has been shown to be retinoic acid receptor mediated, was completely blocked by the pure androgen receptor antagonist casodex (10−6m), indicating that it is androgen receptor dependent. The selective killing effect of 131I in NP-1 cells was 50% in NP-1 cells incubated with 10−9m mib. This was increased to 90% in NP-1 cells treated with atRA (10−7m) plus 10−9m mib. In conclusion, treatment with atRA increases NIS expression levels and selective killing effect of 131I in prostate cancer cells stably expressing NIS under the control of the PSA promoter. Therefore atRA may be used to enhance the therapeutic response to radioiodine in prostate cancer cells following PSA promoter-directed NIS gene delivery.
Regulation of 90-Kilodalton Ribosomal S6 Kinase Phosphorylation in the Rat Pineal Gland
Authors: Ho A. K. , Mackova M. , Cho C. , Chik C. L.
Published: April 2003

In this study we investigated diurnal changes in the activation state of the 90-kDa ribosomal S6 kinase (p90RSK) in the rat pineal gland. In animals housed under a lighting regimen with 12 h of light, we found an increase in phosphorylated p90RSK during the dark phase, and this increase was abolished by treatment with propranolol or continuous exposure to light. To determine the intracellular mechanism involved, rat pinealocytes were treated with norepinephrine. Norepinephrine caused a parallel increase in phosphorylated p42/44 MAPK (p42/44MAPK) and p90RSK that was reduced by prazosin or propranolol, indicating involvement of both α1- and β-adrenergic receptors. Treatment with dibutyryl cGMP, 4β-phorbol 12-myristate 13-acetate, or ionomycin mimicked norepinephrine-stimulated p90RSK phosphorylation, whereas dibutyryl cAMP caused a decrease in p90RSK phosphorylation. Inhibition of p42/44MAPK activation by UO126 was effective in reducing norepinephrine-stimulated p90RSK phosphorylation. Moreover, UO126 had an inhibitory effect on norepinephrine-stimulated arylalkyl-N-acetyltransferase activity. These results indicate that the adrenergically regulated nocturnal increase in p90RSK phosphorylation is mainly mediated through a cGMP→p42/44MAPK-dependent mechanism.
Overexpression of Activin βC or Activin βE in the Mouse Liver Inhibits Regenerative Deoxyribonucleic Acid Synthesis of Hepatic Cells
Authors: Chabicovsky Monika , Herkner Kurt , Rossmanith Walter
Published: April 2003

Activins are dimeric growth factors composed of β-subunits, four of which have been isolated so far. Whereas activin βA and βB are expressed in many tissues, the expression of activin βC and βE is confined to the liver. To date no biological role or activity has been assigned to activins formed from βC or βE subunits (activin C and E). Because activin A (βAβA), among its various functions in other tissues, appears to be a negative regulator of liver growth, we hypothesized a similar role for activin C and E. Using a nonviral gene transfer system we specifically delivered genes encoding activin βC, βE, or βA to the mouse liver. The mRNA analysis and reporter gene coexpression both indicated a reproducible temporal and spatial transgene expression pattern. The effects of activin overexpression were studied in the context of a regenerative proliferation of hepatic cells, a result of the tissue damage associated with the hydrodynamics based gene transfer procedure. Activin βC, βE, or βA expression, all temporarily inhibited regenerative DNA synthesis of hepatocytes and nonparenchymal cells, though to a varying degree. This first report of a biological activity of activin C and E supports an involvement in liver tissue homeostasis and further emphasizes the role of the growing activin family in liver physiology.
Courting Future Resource Conflict: The Shortcomings of Western Response Strategies to New Energy Vulnerabilities
Authors: Peters Susanne
Published: April 2003

With the phenomenon of economic globalization having absorbed our attention for the last decade, environmental challenges as well as the necessity to manage the distribution of resources have been neglected. This paper focuses on the potential for future resource conflicts among states which – as will be argued – will be fought along the axis of the consumers and producers of energy. Conflict over resources can be provoked by the increased energy import dependency of some Western states, intensified by a progressive process of global fossil fuels depletion. The strategies of the West to prevent and manage this type of conflict – risk reduction, crisis management and geopolitics of energy – will be evaluated according to their effectiveness. It will be argued that these strategies might be effective in the short- and mid term but are inadequate in the long term, and that Western states cannot depend on them to prevent a conflict over fossil fuels. The focus of the study is the EU and its precarious strategy of “risk reduction” which, in effect, places all the eggs in the Russian basket. The discussion of Western crisis management as implemented by the International Energy Agency also points to their lack of reliability and effectiveness to manage a severe shortage crisis. The third strategy to prevent and manage supply crisis for the West – a geopolitics of energy – might work in the short run by furnishing Western states' control of cheap oil, but is counterproductive in the long run by deepening the chasm between them and the producer countries on whose energy they depend. The only two effective and complementary strategies to avoid conflict over resources would be to start to reduce the dependency on fossil fuels by developing alternative and renewable energy, and, most of all, to pursue a global policy based on a more equitable and controlled energy distribution.
In Situ Zymography: A Molecular Pathology Technique to Localize Endogenous Protease Activity in Tissue Sections
Authors: Yan S. J. , Blomme E. A. G.
Published: April 2003

Proteases play important roles in modulating a wide range of cellular functions, in the regulation of biologic processes, and in the pathogenesis of various diseases. Several molecular techniques are available to identify and characterize proteases in cells and tissues. Most of these techniques do not provide information on the activity of proteases in tissues. In situ zymography (ISZ) is a relatively lowcost technique that uses specific protease substrates to detect and localize specific protease activities in tissue sections. Used in combination with other techniques, ISZ provides data that further our understanding of the role of specific proteases in various pathologic and physiologic conditions. This review describes the general principle of ISZ and highlights the past and future applications of this technique in molecular pathology.
Clinical and Pathologic Relevance of p53 Index in Canine Osseous Tumors
Authors: Loukopoulos P. , Thornton J. R. , Robinson W. F.
Published: April 2003

The clinicopathologic value of the immunohistochemical (IHC) expression of p53 protein was evaluated in 167 canine osseous tumors. p53 staining frequency and intensity in tumor cells was expressed as a p53 index. p53 index was significantly higher in osteosarcomas than in other sarcomas, chondrosarcoma, multilobular tumor of bone, and tumors initially misdiagnosed as osteosarcomas as well as in appendicular versus axial and in distal versus proximal osteosarcomas. A strong correlation is demonstrated between the p53 index and a range of clinicopathologic parameters in osteosarcoma, including the tumor site, histologic grade and score, mitotic index, degree of tumor necrosis, and pleomorphism. Chondroblastic osteosarcomas had significantly higher and telangiectatic osteosarcomas significantly lower p53 index than did osteosarcomas belonging to other histopathologic subtypes, a fact that tends to reinforce the perception of these osteosarcomas as distinct clinicopathologic entities. Entire males had higher p53 index than did neutered males. p53 index was higher in Rottweilers than in Great Danes and Terriers, confirming breed susceptibilities to osteosarcoma. p53 index showed no association with age, primary or secondary site status, or the presence of metastases or other tumor types. Biopsy samples had a higher p53 index than did postmortem samples, either because of differences in sample processing or the possibility that p53 overexpression is more evident at the earlier stages of osteosarcoma pathogenesis, presumably represented by the biopsy material. IHC examination for p53 and the derived index has the potential to be used as an additional diagnostic tool and prognostic indicator for osseous tumors.
Morphometry of Canine Cutaneous Mast Cell Tumors
Authors: Strefezzi R. De F. , Xavier J. G. , Catão-Dias J. L.
Published: April 2003

Twenty-four canine cutaneous nodules, diagnosed as mast cell tumors by fine-needle aspiration biopsy and confirmed by histopathologic analysis by staining with hematoxylin and eosin (HE) and toluidine blue, were analyzed by computerized nuclear morphometry on panoptic- and HE-stained cytopathology slides. Two hundred nuclei per lesion were examined. The morphometric parameters investigated were nuclear area, mean diameter, perimeter, regularity factor, and ellipticity factor. Lesions were graded as I (well differentiated), II (intermediate differentiation), or III (poorly differentiated) according to the following morphologic features: invasiveness, cellularity and cellular morphology, mitotic index, and stromal reaction. Nuclear morphometric results were then compared with histopathologic grades. Values of nuclear area, mean diameter, and perimeter increased with increase in histopathologic grade, but statistical analysis revealed significant differences only between grades II and III and between grades I and III when HE was used ( P, 0.01) and between grades I and III with panoptic stain ( P, 0.05). The ellipticity factor and regularity factor did not reveal significant differences between histopathologic grades. The results indicate that nuclear morphometric analysis, in combination with the rapid and inexpensive cytopathology technique, can help in mast cell tumor grading, thus contributing to the establishment of a more precise prognosis and treatment.
Evidence of Nitric Oxide Synthase 2 Activity in Swine Naturally Infected with Actinobacillus pleuropneumoniae
Authors: Cho W.-S. , Chae C.
Published: April 2003

Evidence of nitric oxide synthase (NOS) 2 activity was determined by formation of nitrotyrosine (a reaction product of peroxynitrite) and by activation of poly(ADP-ribose) synthetase (PARS) in NOS2-expressed pleuropneumonic lungs from 20 pigs naturally infected with Actinobacillus pleuropneumoniae using immunohistochemistry. Intense immunostaining for nitrotyrosine residue was seen within the lung lesions from A. pleuropneumoniae-infected pigs, but it was minimal in the unaffected parts of the lung from A. pleuropneumoniae-infected pigs and in the normal lung from control pigs. Staining was especially strong in neutrophils and macrophages in the periphery of the lesions and within the alveolar spaces. There was close cell-to-cell correlation when serial sections were examined by immunohistochemistry for NOS2 and nitrotyrosine in each of the 20 lung samples. Expression of PARS was always present within inflammatory lesions but was minimal in the unaffected lung of A. pleuropneumoniae-infected pigs. Macrophages in alveolar spaces frequently exhibited strong staining for PARS. Colocalization of nitrotyrosine and PARS antigen was especially prominent in macrophages in the periphery of lesions. NOS2 expression in pleuropneumonic areas associated with protein nitrosation and PARS suggests that NOS2 is functionally active during infections caused by A. pleuropneumoniae.
Adenoviral Gizzard Erosion in Commercial Broiler Chickens
Authors: Ono M. , Okuda Y. , Yazawa S. , Imai Y. , Shibata I. , Sato S. , Okada K.
Published: April 2003

Pathologic and immunohistochemical changes caused by group I of the fowl adenovirus (FAV) serotype-1 99ZH strain, isolated from broiler chickens exhibiting gizzard erosion, were investigated in commercial broiler chickens. One hundred twenty-two chickens were inoculated with the strain by both oral and ocular routes at 1, 3, or 5 weeks of age and euthanatized for necropsy within 4–18 days of inoculation. Focal gizzard erosions were observed in the inoculated chickens of each age group. A histologically degenerative koilin layer, necrotic mucosa, intranuclear inclusion bodies in the glandular epithelial cells, inflammatory cell infiltrations in the lamina propria, submucosa, and a muscle layer were seen in the gizzards. Immunohistochemical staining showed evidence of FAV antigens in the intranuclear inclusion bodies. These findings were recognized regardless of their maternal antibody levels for FAV serotype-1. Gizzard lesions appeared later in the lower-dose-inoculated chickens than in the higher-dose–inoculated chickens. Numerous CD3-positive cells and IgY-positive plasma cells were seen in the gizzard lesions. In 5-week-old chickens the heterophil infiltrations in the lesions were milder than in younger chickens. Intranuclear inclusion bodies also were observed in the epithelial cells of the ileum or cecal tonsils of some chickens. Thus, this study shows that FAV-99ZH causes adenoviral gizzard erosion in broiler chickens without hepatic or pancreatic lesions and that cell infiltration is more severe than in dietary gizzard erosions.
Hemochromatosis Secondary to Repeated Blood Transfusions in a Dog
Authors: Sprague W. S. , Hackett T. B. , Johnson J. S. , Swardson-Olver C. J.
Published: April 2003

Hemochromatosis was presumptively diagnosed using cytologic examination of liver tissue from an aged male Miniature Schnauzer. The dog was presented after receiving whole blood transfusion every 6–8 weeks for 3 years to treat pure red cell aplasia. The cytologic specimen contained clusters of hepatocytes with abundant intracytoplasmic gold-yellow pigment granules and clumps of extracellular, green-black, globular pigment, both interpreted to be hemosiderin. Histologic sections of liver revealed hepatocellular degeneration with bridging portal fibrosis, lobular atrophy, biliary hyperplasia, and diffuse, severe hemosiderin accumulation. Serum iron and ferritin levels, and dry-weight iron concentrations of liver, heart, and kidneys were markedly increased. Hemosiderin accumulation was confirmed in hepatocytes of cytologic and histologic specimens using Perl's Prussian blue staining. This report is the first description of transfusional hemochromatosis in a dog and is the first to describe its cytologic appearance in a veterinary patient.
Septic Peritonitis Due to Colonic Perforation Associated with Aberrant Migration of a Gasterophilus intestinalis Larva in a Horse
Authors: Lapointe J.-M. , Céleste C. , Villeneuve A.
Published: April 2003

An adult quarter horse mare was presented with acute colic and fever. Physical examination and abdominocentesis showed septic peritonitis, and the mare was euthanatized. Necropsy and histopathologic examination revealed a focal partial perforation of the right ventral colon, which contained a single bot fly larva, identified as a third-instar larva of Gasterophilus intestinalis. This larva was embedded deep within the muscularis and the submucosa. Although bot fly larvae are known to attach to aberrant sites within the digestive tract, this is the first known report of deep penetration of the colon by a gasterophilus larva, with the resulting leakage of intestinal content leading to septic peritonitis.
Anti‐neuronal nuclear autoantibody type 2: Paraneoplastic accompaniments
Authors: Pittock Sean J. , Lucchinetti Claudia F. , Lennon Vanda A.
Published: April 2003

We identified the IgG autoantibody ANNA‐2 (“anti‐Ri”) in 34 patients in a 12‐year period by immunofluorescence screening of sera from approximately 75,000 patients with subacute neurological disorders that were suspected to be paraneoplastic. Detailed clinical information was available for 28 patients (10 men, 18 women). Cancer was diagnosed in 24 patients (86%); 21 had histologically proven carcinoma (10 lung, 9 breast, 1 cervical, 1 bladder), and 3 had an intrathoracic imaging abnormality. Cancer anteceded neurological symptoms in 4 of 28 patients. Cancer detection frequency increased with continued surveillance. Neurological disorders, in decreasing frequency, were brainstem syndrome (including opsoclonus, myoclonus, or both), cerebellar syndrome, myelopathy, peripheral neuropathy, cranial neuropathy, movement disorder, encephalopathy, Lambert–Eaton syndrome, and seizures. Four patients had laryngospasm and four had jaw opening dystonia (two with neck dystonia). Nine (32%) were wheelchair‐bound 1 month after neurological symptom onset. Most improved neurologically after immunomodulatory or tumor‐directed therapy. Accompanying autoantibodies, found in 73% of sera, included ANNA‐1, ANNA‐3, CRMP‐5‐IgG, P/Q‐type and N‐type Ca2+ channel antibodies, and muscle‐type acetylcholine receptor antibody. Some neurological accompaniments of ANNA‐2 may reflect potentially pathogenic humoral or cell‐mediated responses to coimmunogenic tumor antigens, for example, Lambert–Eaton syndrome (P/Q‐type Ca2+ channel antibody) and peripheral neuropathy (ANNA‐1 effector T cells). Ann Neurol 2003
Endogenous dopamine release after pharmacological challenges in Parkinson's disease
Authors: Piccini Paola , Pavese Nicola , Brooks David J.
Published: April 2003

Using 11C‐raclopride positron emission tomography after methamphetamine challenge, we have evaluated regional brain changes in synaptic dopamine (DA) levels in six volunteers and six advanced Parkinson's disease (PD) patients. The pharmacological challenge induced significant release of endogenous DA in putamen not only in the normal subjects, as reflected by a 25.2% reduction in 11C‐raclopride binding potential as compared with placebo, but also in the PD patients (6.8%). In individual PD patients, we found a correlation between putamen DA release and DA storage, as measured by 18F‐dopa uptake. Localization of significant changes in 11C‐raclopride binding after methamphetamine at a voxel level with statistical parametric mapping identified striatal and prefrontal DA release in both cohorts. Statistical comparisons between normal subjects and PD confirmed significantly reduced DA release in striatal areas in PD, but normal levels of prefrontal DA release. In conclusion, significant endogenous DA release can still be induced by pharmacological challenges in the putamen of advanced PD patients, and this release correlates with residual DA storage capacity. Our data also show that the capacity to release normal DA levels in prefrontal areas after a pharmacological challenge is preserved in severe stages of the disease. Ann Neurol 2003
Efficient central nervous system remyelination requires T cells
Authors: Bieber Allan J. , Kerr Scott , Rodriguez Moses
Published: April 2003

We demonstrate a role for immune functions in the spontaneous remyelination of central nervous system (CNS) axons after lysolecithin‐induced demyelination in the spinal cord. Rag‐1–deficient mice lack both B cells and T cells and show significantly reduced spontaneous remyelination compared with control mice of matching genetic background. Mice lacking or depleted of either CD4+ T cells or CD8+ T cells also exhibit reduced remyelination. These data indicate that T cells are necessary for efficient CNS remyelination. Thus, general nonspecific immunosuppression as a therapeutic approach for the treatment of CNS injury and demyelinating disease may have undesirable effects on subsequent tissue repair. Ann Neurol 2003;53:680–684
Measuring Gender Bias in the Salaries of Tenured Faculty Members
Authors: Becker William E. , Toutkoushian Robert K.
Published: April 2003

A sample selection statistical procedure is used to correct for the effects on salary of gender bias in promotion from associate to full professor.
Development of a bulgur‐like product using extrusion cooking
Authors: Köksel Hamit , Ryu Gi‐Hyung , Özboy‐Özbas Özen , Basman Arzu , Ng Perry K W
Published: April 2003

In this study we (1) developed a new bulgur‐like foodstuff using a durum wheat cultivar and an extrusion technique, (2) investigated the physicochemical properties of the extrudates produced and (3) sensorially evaluated the end‐product after cooking. Durum wheat was processed in a laboratory‐scale co‐rotating twin‐screw extruder with different levels of moisture content of the feed (367, 417 and 455 g kg−1), screw speed (150 and 200 rpm) and feed rate (2.4 and 2.9 kg h−1) to develop the bulgur‐like product. The effects of extrusion conditions on system variables (die pressure and specific mechanical energy (SME)), physical properties (die swell and bulk density), pasting properties (peak, trough and final viscosities) and cooking and sensory properties of the bulgur‐like products were determined. The results indicated that increased feed moisture content resulted in significant decreases in the die pressure and SME values of the extruded durum wheat products. As the moisture content and screw speed increased, the changes in die swell values were not significant. The lowest die swell and highest bulk density values were obtained at the highest feed moisture content. The extrusion variables also affected the pasting properties of the extrudates. Significant increases in each of the pasting properties occurred when the moisture content of the feed was increased. Some of the sensory properties (bulkiness, firmness, stickiness and taste–aroma) improved significantly as the feed moisture content increased, indicating better quality. Increased feed moisture content significantly improved cooking quality as determined by a decrease in colorimetric test results. Extrusion seems to be promising for the production of dry, relatively inexpensive bulgur‐like products with acceptable sensory properties.

© 2003 Society of Chemical Industry
Detecting early response to cyclophosphamide treatment of RIF‐1 tumors using selective multiple quantum spectroscopy (SelMQC) and dynamic contrast enhanced imaging
Authors: Poptani Harish , Bansal Navin , Graham Robert A. , Mancuso Anthony , Nelson David S. , Glickson Jerry D.
Published: April 2003

The purpose of this study was to develop a reliable, noninvasive method for early detection of tumor response to therapy that would facilitate optimization of treatment regimens to the needs of the individual patient. In the present study, the effects of cyclophosphamide (Cp, a widely used alkylating agent) were monitored in a murine radiation induced fibrosarcoma (RIF‐1) using in vivo 1H NMR spectroscopy and imaging to evaluate the potential of these techniques towards early detection of treatment response. Steady‐state lactate levels and Gd‐DTPA uptake kinetics were measured using selective multiple quantum coherence (Sel‐MQC) transfer spectroscopy and dynamic contrast enhanced imaging, respectively in RIF‐1 tumors before, 24 and 72 h after 300 mg/kg of Cp administration. High‐resolution 1H NMR spectra of perchloric acid extracts of the tumor were correlated with lactate and glucose concentrations determined enzymatically. In vivo NMR experiments showed a decrease in steady‐state lactate to water ratios (5.4 ± 1.6 to 0.6 ± 0.5, p < 0.05) and an increase in Gd‐DTPA uptake kinetics following treatment response. The data indicate that decreases in lactate result from decreased glycolytic metabolism and an increase in tumor perfusion/permeability. Perchloric acid extracts confirmed the lower lactate levels seen in vivo in treated tumors and also indicated a higher glycerophosphocholine/phosphocholine (GPC/PC) integrated intensity ratio (1.39 ± 0.09 vs 0.97 ± 0.04, p < 0.01), indicative of increased membrane degradation following Cp treatment. Steady‐state lactate levels provide metabolic information that correlates with changes in tumor physiology measured by Gd‐DTPA uptake kinetics with high spatial and temporal resolution. Both of these parameters may be useful for monitoring early tumor response to therapy. Copyright © 2003 John Wiley & Sons, Ltd.
Specificity of peptide selection by antigen-presenting cells homozygous or heterozygous for expression of class II MHC molecules: The lack of competition
Authors: Suri Anish , Walters James J. , Kanagawa Osami , Gross Michael L. , Unanue Emil R.
Published: April 2003

We isolated and identified naturally processed peptides selected by antigen-presenting cells homozygous for expression of I-Ag7or I-Adclass II MHC molecules, or from heterozygous antigen-presenting cells that express I-Ag7along with I-Ag7PDor I-Ad. Identification of large numbers of peptides demonstrated that despite being closely related on a structural level, each class II MHC molecule selected for very unique peptides. The large data sets allowed us to definitively establish the preferred peptide-binding motifs critical for selection of peptides by I-Ag7, I-Ag7PD, and I-Ad. Finally, extensive analyses of peptide families reveals that there was little competition among class II MHC alleles for display of peptides and that presence of one allele had minimal impact on the repertoire of peptides selected by another.
Human capillary morphogenesis protein 2 functions as an anthrax toxin receptor
Authors: Scobie Heather M. , Rainey G. Jonah A. , Bradley Kenneth A. , Young John A. T.
Published: April 2003

Bacillus anthracis
secretes two bipartite toxins thought to be involved in anthrax pathogenesis and resulting death of the host. The current model for intoxication is that protective antigen (PA) toxin subunits bind a single group of cell-surface anthrax toxin receptors (ATRs), encoded by the
tumor endothelial marker 8
(
TEM8
) gene. The ATR/TEM8-PA interaction is mediated by the receptor's extracellular domain related to von Willebrand factor type A or integrin inserted domains (VWA/I domains). A metal ion-dependent adhesion site (MIDAS) located within this domain of the ATR/TEM8 protein chelates a divalent cation critical for PA binding. In this report, we identify a second PA receptor encoded by
capillary morphogenesis gene 2
(
CMG2
), which has 60% amino acid identity to ATR/TEM8 within the VWA/I domain, as well as a conserved MIDAS motif. A recombinant CMG2 protein bound PA and mediated toxin internalization when expressed on receptor-deficient cells. Binding between the CMG2 VWA/I domain and PA was shown to be direct and metal-dependent, although the cation specificity of this interaction is different than that observed with ATR/TEM8. Northern blot analysis revealed that CMG2 is widely expressed in human tissues, indicating that this receptor is likely to be relevant for disease pathogenesis. Finally, a soluble version of the CMG2 VWA/I domain inhibited intoxication of cells expressing endogenous toxin receptors when it was added to PA at a 3:1 ratio. These studies distinguish CMG2 as a second anthrax toxin receptor and identify a potent antitoxin that may prove useful for the treatment of anthrax.
Stable and controllable RNA interference: Investigating the physiological function of glutathionylated actin
Authors: Wang Jun , Tekle Ephrem , Oubrahim Hammou , Mieyal John J. , Stadtman Earl R. , Chock P. Boon
Published: April 2003

RNA interference is an effective method to silence specific gene expression. Its application to mammalian cells, however, has been hampered by various shortcomings. Recently, it was reported that introduction of 22-bp double-stranded RNAs (dsRNAs) would specifically suppress expression of endogenous and heterogeneous genes in various mammalian cell lines. However, using this method, we failed to knock out proteins of interest effectively. Here we report the development of a stable and controllable method for generating dsRNA intracellularly. Tetracycline-responsive transactivator-containing cells were transfected with a vector capable of tetracycline-induced bidirectionally overexpressing sense and antisense RNA to form dsRNA
in vivo
. With this method, glutaredoxin, monitored by Western blot, was knocked out by overexpressing 290-base sense and antisense RNA in NIH 3T3 cells controlled by tetracycline or doxycycline. By using these glutaredoxin knocked-out cells, we have demonstrated that actin deglutathionylation plays a key role in growth factor-mediated actin polymerization, translocalization, and reorganization near the cell periphery.
A strategy for identifying transcription factor binding sites reveals two classes of genomic c-Myc target sites
Authors: Haggerty Timothy J. , Zeller Karen I. , Osthus Rebecca C. , Wonsey Diane R. , Dang Chi V.
Published: April 2003

Defining the hardwiring of transcription factors to their cognate genomic binding sites is essential for our understanding of biological processes. We used scanning chromatin immunoprecipitation to identify
in vivo
binding regions (E boxes) for c-Myc in three target genes as a model system. Along with other c-Myc target genes that have been validated by chromatin immunoprecipitation, we used the publicly available genomic sequences to determine whether experimentally derived
in vivo
binding sites might be predictable from nonexonic sequence conservation across species. Our studies revealed two classes of target genomic binding sites. Although the majority of target genes studied [class I:

B23

(
NPM1
),
CAD
,
CDK4
, cyclin D2,
ID2
,
LDH
-
A
,
MNT
,
PTMa
,
ODC
,
NM23B
, nucleolin, prohibitin,
SHMT1
, and
SHMT2
] demonstrate significant sequence conservation of the E boxes and flanking regions, several genes (cyclin B1,
JPO1
, and
PRDX3
) belong to a second class (class II) that does not display sequence conservation at and around the site of c-Myc binding. On the basis of our model, we propose a strategy for predicting transcription factor binding sites using phylogenetic sequence comparisons, which will select potential class I target genes among the many emerging candidates from DNA-microarray studies for experimental validation by chromatin immunoprecipitation.
Overexpression of barley BAX inhibitor 1 induces breakdown of
mlo
-mediated penetration resistance to
Blumeria graminis
Authors: Hückelhoven Ralph , Dechert Cornelia , Kogel Karl-Heinz
Published: April 2003

Cell death regulation is linked to pathogen defense in plants and animals. Execution of apoptosis as one type of programmed cell death in animals is irreversibly triggered by cytochrome
c
release from mitochondria via pores formed by BAX proteins. This type of programmed cell death can be prevented by expression of BAX inhibitor 1 (
BI-1
), a membrane protein that protects cells from the effects of BAX by an unknown mechanism. In barley, a homologue of the mammalian
BI-1
is expressed in response to inoculation with the barley powdery mildew fungus
Blumeria graminis
f.sp.
hordei
(
Bgh
). We found differential expression of
BI-1
in response to
Bgh
in susceptible and resistant plants. Chemical induction of resistance to
Bgh
by soil drench treatment with 2,6-dichloroisonicotinic acid led to down-regulation of the expression level of
BI-1
. Importantly, single-cell transient overexpression of
BI-1
in epidermal leaf tissue of susceptible barley cultivar Ingrid led to enhanced accessibility, resulting in a higher penetration efficiency of
Bgh
on
BI-1
-transformed cells. In
Bgh
-resistant
mlo5
genotypes, which do not express the negative regulator of defense and cell death MLO, overexpression of
BI-1
almost completely reconstituted susceptibility to fungal penetration. We suggest that BI-1 is a regulator of cellular defense in barley sufficient to substitute for MLO function in accessibility to fungal parasites.
Functional role of L-type Ca
v
1.3 Ca
2+
channels in cardiac pacemaker activity
Authors: Mangoni Matteo E. , Couette Brigitte , Bourinet Emmanuel , Platzer Josef , Reimer Daniel , Striessnig Jörg , Nargeot Joël
Published: April 2003

The spontaneous activity of pacemaker cells in the sino-atrial node (SAN) controls the heart rhythm and rate under physiological conditions. Pacemaker activity in SAN cells is due to the presence of the diastolic depolarization, a slow depolarization phase that drives the membrane voltage from the end of an action potential to the threshold of a new action potential. SAN cells express a wide array of ionic channels, but we have limited knowledge about their functional role in pacemaker activity and we still do not know which channels play a prominent role in the generation of the diastolic depolarization. It is thus important to provide genetic evidence linking the activity of genes coding for ionic channels to specific alterations of pacemaker activity of SAN cells. Here, we show that target inactivation of the gene coding for α
1D
(Ca
v
1.3) Ca
2+
channels in the mouse not only significantly slows pacemaker activity but also promotes spontaneous arrhythmia in SAN pacemaker cells. These alterations of pacemaker activity are linked to abolition of the major component of the L-type current (
I
Ca,L
) activating at negative voltages. Pharmacological analysis of
I
Ca,L
demonstrates that Ca
v
1.3 gene inactivation specifically abolishes
I
Ca,L
in the voltage range corresponding to the diastolic depolarization. Taken together, our data demonstrate that Ca
v
1.3 channels play a major role in the generation of cardiac pacemaker activity by contributing to diastolic depolarization in SAN pacemaker cells.
A Phase Response Curve to Single Bright Light Pulses in Human Subjects
Authors: Khalsa Sat Bir S. , Jewett Megan E. , Cajochen Christian , Czeisler Charles A.
Published: April 2003

The circadian pacemaker is differentially sensitive to the resetting effects of retinal light exposure, depending upon the circadian phase at which the light exposure occurs. Previously reported human phase response curves (PRCs) to single bright light exposures have employed small sample sizes, and were often based on relatively imprecise estimates of circadian phase and phase resetting. In the present study, 21 healthy, entrained subjects underwent pre‐ and post‐stimulus constant routines (CRs) in dim light (∼2–7 lx) with maintained wakefulness in a semi‐recumbent posture. The 6.7 h bright light exposure stimulus consisted of alternating 6 min fixed gaze (∼10 000 lx) and free gaze (∼5000–9000 lx) exposures. Light exposures were scheduled across the circadian cycle in different subjects so as to derive a PRC. Plasma melatonin was used to determine the phase of the onset, offset, and midpoint of the melatonin profiles during the CRs. Phase shifts were calculated as the difference in phase between the pre‐ and post‐stimulus CRs. The resultant PRC of the midpoint of the melatonin rhythm revealed a characteristic type 1 PRC with a significant peak‐to‐trough amplitude of 5.02 h. Phase delays occurred when the light stimulus was centred prior to the critical phase at the core body temperature minimum, phase advances occurred when the light stimulus was centred after the critical phase, and no phase shift occurred at the critical phase. During the subjective day, no prolonged ‘dead zone’ of photic insensitivity was apparent. Phase shifts derived using the melatonin onsets showed larger magnitudes than those derived from the melatonin offsets. These data provide a comprehensive characterization of the human PRC under highly controlled laboratory conditions.
L∞‐error estimate for a system of elliptic quasivariational inequalities
Authors: Boulbrachene M. , Haiour M. , Saadi S.
Published: April 2003

We deal with the numerical analysis of a system of elliptic quasivariational inequalities (QVIs). Under W2,p(Ω)‐regularity of the continuous solution, a quasi‐optimal L∞‐convergence of a piecewise linear finite element method is established, involving a monotone algorithm of Bensoussan‐Lions type and standard uniform error estimates known for elliptic variational inequalities (VIs).
Trajectories under a vectorial potential on stationary manifolds
Authors: Bartolo Rossella
Published: April 2003

By using variational methods, we study the existence and
multiplicity of trajectories under a vectorial potential on (standard) stationary Lorentzian manifolds possibly with boundary.
Fluid queues driven by a discouraged arrivals queue
Authors: Parthasarathy P. R. , Vijayashree K. V.
Published: April 2003

We consider a fluid queue driven by a discouraged arrivals queue
and obtain explicit expressions for the stationary distribution
function of the buffer content in terms of confluent
hypergeometric functions. We compare it with a fluid queue driven
by an infinite server queue. Numerical results are presented to
compare the behaviour of the buffer content distributions for both
these models.
Modulus of smoothness and theorems concerning approximation on compact groups
Authors: Vaezi H. , Rzaev S. F.
Published: April 2003

We consider the generalized shift operator defined by (Shuf)(g) = ∫Gf(tut−1g)dt on a compact group G, and by using this operator, we define spherical modulus of smoothness. So, we prove Stechkin and Jackson‐type theorems.
Linear neutral partial differential equations: a semigroup approach
Authors: Nagel Rainer , Huy Nguyen Thieu
Published: April 2003

We study linear neutral PDEs of the form (∂/∂t)Fut = BFut + Φut, t ≥ 0; u0(t) = φ(t), t ≤ 0, where the function u(⋅) takes values in a Banach
space X. Under appropriate conditions on the difference
operator F and the delay operator Φ, we construct a C0‐semigroup on C0(ℝ−, X) yielding the solutions
of the equation.
The derangement problem relative to the Mahonian process
Authors: Delfert Jessica , Einziger Hillary , Rawlings Don
Published: April 2003

We survey n! plus q‐derangement problems. Solutions to four
Mahonian statistics arising in connection with cycle placement
rules are presented. A few conjectures are also made.
Mann iterates of directionally nonexpansive mappings in hyperbolic spaces
Authors: Kohlenbach Ulrich , Leuştean Laurenţiu
Published: April 2003

In a previous paper, the first author derived an explicit quantitative version of a theorem due to Borwein, Reich, and Shafrir on the asymptotic behaviour of Mann iterations of
nonexpansive mappings of convex sets C in normed linear spaces. This quantitative version, which was obtained by a logical analysis of the ineffective proof given by Borwein, Reich, and Shafrir, could be used to obtain strong uniform bounds on the asymptotic regularity of such iterations in the case of bounded C and even weaker conditions. In this paper, we extend these results to hyperbolic spaces and directionally nonexpansive mappings. In particular, we obtain significantly stronger and more general forms of the main results of a recent paper by W. A.
Kirk with explicit bounds. As a special feature of our approach, which is based on logical analysis instead of functional analysis, no functional analytic embeddings are needed to obtain our uniformity results which contain all previously known results of this kind as special cases.
Domains which are locally uniformly linearly convex in the Kobayashi distance
Authors: Budzyńska Monika
Published: April 2003

We show a construction of domains in complex reflexive Banach spaces which are locally uniformly convex in linear sense in their Kobayashi distance. We also show connections between norm and Kobayashi distance properties.
Transcriptional Targeting in Cancer Gene Therapy
Authors: Robson Tracy , Hirst David G.
Published: April 2003

Cancer gene therapy has been one of the most exciting areas of therapeutic research in the past decade. In this review, we discuss strategies to restrict transcription of transgenes to
tumour cells. A range of promoters which are tissue‐specific, tumour‐specific, or inducible by exogenous agents are presented. Transcriptional targeting should prevent normal tissue toxicities
associated with other cancer treatments, such as radiation and chemotherapy. In addition, the specificity of these strategies should provide improved targeting of metastatic tumours following
systemic gene delivery. Rapid progress in the ability to specifically control transgenes will allow systemic gene delivery for cancer therapy to become a real possibility in the near
future.
Stat5 expression is critical for mast cell development and survival
Authors: Shelburne Christopher P. , McCoy Margaret E. , Piekorz Roland , Sexl Veronica , Roh Kwan-Ho , Jacobs-Helber Sarah M. , Gillespie Sheila R. , Bailey Daniel P. , Mirmonsef Paria , Mann Meredith N. , Kashyap Mohit , Wright Harry V. , Chong Hey Jin , Bouton L. Andrew , Barnstein Brian , Ramirez Carlos D. , Bunting Kevin D. , Sawyer Steven , Lantz Chris S. , Ryan John J.
Published: April 2003

Interleukin-3 (IL-3) and stem cell factor (SCF) are important mast cell growth and differentiation factors. Since both cytokines activate the transcription factor signal transducer and activator of transcription 5 (Stat5), a known regulator of proliferation and survival, we investigated the effects of Stat5 deficiency on mast cell development and survival. Bone marrow–derived mast cell (BMMC) populations cultured from Stat5A/B-deficient mice survived in IL-3 + SCF, but not in either cytokine alone. These cells demonstrated reduced expression of Bcl-2, Bcl-x(L), cyclin A2, and cyclin B1, with increased apoptosis and delayed cell cycle progression during IL-3 or SCF culture. Finally, the absence of Stat5 resulted in loss of in vivo mast cell development, as judged by assessments of Stat5-deficient mice and transplantation of Stat5-deficient bone marrow cells to mast cell-deficient recipient mice. These results indicate that Stat5A and Stat5B are critical regulators of in vitro and in vivo mast cell development and survival.
Randomized Controlled Trial of Exercise Training in Postmenopausal Breast Cancer Survivors: Cardiopulmonary and Quality of Life Outcomes
Authors: Courneya Kerry S. , Mackey John R. , Bell Gordon J. , Jones Lee W. , Field Catherine J. , Fairey Adrian S.
Published: April 2003

Purpose: To determine the effects of exercise training on cardiopulmonary function and quality of life (QOL) in postmenopausal breast cancer survivors who had completed surgery, radiotherapy, and/or chemotherapy with or without current hormone therapy use.

Methods: Fifty-three postmenopausal breast cancer survivors were randomly assigned to an exercise (n = 25) or control (n = 28) group. The exercise group trained on cycle ergometers three times per week for 15 weeks at a power output that elicited the ventilatory equivalent for carbon dioxide. The control group did not train. The primary outcomes were changes in peak oxygen consumption and overall QOL from baseline to postintervention. Peak oxygen consumption was assessed by a graded exercise test using gas exchange analysis. Overall QOL was assessed by the Functional Assessment of Cancer Therapy–Breast scale.

Results: Fifty-two participants completed the trial. The exercise group completed 98.4% of the exercise sessions. Baseline values for peak oxygen consumption (P = .254) and overall QOL (P = .286) did not differ between groups. Peak oxygen consumption increased by 0.24 L/min in the exercise group, whereas it decreased by 0.05 L/min in the control group (mean difference, 0.29 L/min; 95% confidence interval [CI], 0.18 to 0.40; P < .001). Overall QOL increased by 9.1 points in the exercise group compared with 0.3 points in the control group (mean difference, 8.8 points; 95% CI, 3.6 to 14.0; P = .001). Pearson correlations indicated that change in peak oxygen consumption correlated with change in overall QOL (r = 0.45; P < .01).

Conclusion: Exercise training had beneficial effects on cardiopulmonary function and QOL in postmenopausal breast cancer survivors.
Primary Mediastinal Large B-Cell Lymphoma With Sclerosis in Pediatric and Adolescent Patients: Treatment and Results From Three Therapeutic Studies of the Berlin-Frankfurt-Münster Group
Authors: Seidemann K. , Tiemann M. , Lauterbach I. , Mann G. , Simonitsch I. , Stankewitz K. , Schrappe M. , Zimmermann M. , Niemeyer C. , Parwaresch R. , Riehm H. , Reiter A.
Published: April 2003

Purpose: Primary mediastinal large B-cell lymphoma with sclerosis (PMLBL) is a rare entity of non-Hodgkin’s lymphoma (NHL) arising from thymic mature B cells. Optimal treatment strategies remain to be established, especially in pediatric patients.

Patients and Methods: This study analyzes clinical characteristics and treatment outcome of 30 pediatric patients with PMLBL, diagnosed in multicenter therapy NHL–Berlin-Frankfurt-Münster Group (BFM) trials. Treatment was stratified by stage and serum lactate dehydrogenase (LDH) and consisted of four to six 5-day courses of chemotherapy using steroids, oxazaphosphorine alkylating agents, methotrexate, cytarabine, etoposide, and doxorubicin. Radiation was not part of the protocol.

Results: From April 1986 to August 1999, 1,650 patients with newly diagnosed NHL were enrolled in the NHL-BFM trials; 30 patients (1.8%) had PMLBL. Median age was 14.3 years (range, 1.4 to 16.7 years); 15 patients were male and 15 patients were female. With a median observation time of 5 years (range, 1 to 12 years), probability of event-free survival (pEFS) at 5 years was 0.70 (SE, 0.08). Two patients erroneously diagnosed as T-cell NHL received non–B-cell therapy and died from progress of disease. Events in 28 patients receiving B-cell therapy included early progress during therapy (n = 1) and relapse (n = 6). Residual mediastinal masses were present in 23 patients after two courses of therapy and in 15 patients after the end of therapy. LDH ≥ 500 U/L was associated with increased risk of failure in multivariate analysis.

Conclusion: PMLBL mainly is found in adolescents. Dose-intense chemotherapy including high-dose methotrexate yields a pEFS at 5 years of 0.70 (SE, 0.08). LDH is of prognostic value in pediatric patients with PMLBL.