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  • 1
    ISSN: 1573-675X
    Keywords: Apoptosis ; CD95 (Fas/APO-1) ; NF-κB/Rel ; T lymphocytes.
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The activity of NF-κB/Rel transcription factors can inhibit the apoptosis induced by TNF, UV or cancer therapy drugs in a number of cell types, including human T lymphocytes. Furthermore, the NF-κB/Rel inducer, phorbol-12-myristate-13-acetate (PMA), has been reported to suppress the CD95-induced apoptosis of human T lymphocytes. To verify whether the survival-enhancing effect of PMA required NF-κB/Rel activity, we generated two Jurkat cell sublines (AL.7 and AL.8) transfected with a pCMV4-IκBα construct, and two (AL.3 and AL.5) with the void pCMV4 vector. Compared to wild type, AL.3 and AL.5 cells, the AL.7 and AL.8 sublines displayed markedly lower amounts of NF-κB/Rel nuclear complexes and a reduced expression of a κB-controlled CAT reporter gene after 1 and 4 h of incubation with PMA, respectively. All the five cell types displayed negligible levels of apoptosis when cultured with medium or PMA alone; when stimulated with the mAb CH-11, the AL.7 and AL.8 sublines displayed apoptotic responses only slightly (〈0.5 fold) higher than control cells. On the other hand, the salvage activity of PMA was partially impaired in the AL.7 and AL.8 sublines. PMA inhibited apoptosis by 〉85% in wild type, AL.3 and AL.5 cells and by 〈60% in the AL.7 and AL.8 sublines; the apoptosis percentages in the mAb CH-11 + PMA cultures of the IκBα-transfected cells were 〉4-fold higher than in control cells. We conclude that the inhibition of the CD95-induced apoptosis by PMA relies on both NF-κB/Rel-dependent and -independent mechanisms. The partial contribution of these nuclear factors to the suppression of apoptosis indicates that the NF-κB/Rel activity can influence the extent of the CD95-induced T cell death.
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 1434-601X
    Keywords: PACS:26.20.+f Hydrostatic stellar nucleosynthesis – 25.60.Dz Interaction and reaction cross sections
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract: The loss of 8Li recoil nuclei in 7Li(d,p)8Li has been measured using different backings and 7LiF target thicknesses as well as different deuteron energies. The results confirm essentially recent TRIM calculations. The losses are large (about 13%) for the combination of thin targets and heavy backings at E d=0.80 MeV and increase with decreasing deuteron energy. The implications on the cross sections for 7Li(d,p)8Li and 7Be(p,γ)8B are discussed.
    Type of Medium: Electronic Resource
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  • 3
    ISSN: 1434-601X
    Keywords: 25.70-z ; 24.30.Cz ; 25.70.Lm
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract γ-rays are measured in coincidence with the dissipative complex fragments from the35Cl +64Ni reaction at 7.7 A MeV. Theoretical γ-ray coincidence spectra are determined through a fitting procedure using the contribution of the excited fragment statistical γ-decay calculated by means of the CASCADE code. Whereas the expected statistical spectra fit very well the data in the energy regionE ν=2 to 8 MeV, above this energy another emission mechanism in addition to the statistical decay has to be considered in order to reproduce the experimental spectra. Simulations based on the Vlasov equation suggest that this emission could come from the decay of dipole strength excited in the intermediate dinuclear system.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Archives of environmental contamination and toxicology 35 (1998), S. 302-308 
    ISSN: 1432-0703
    Source: Springer Online Journal Archives 1860-2000
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Medicine
    Notes: Abstract. For nearly 50 years, the fingernail clam (Musculium transversum) was believed to be virtually eliminated from the Illinois River. In 1991, workers began finding substantial populations of M. transversum in the Illinois River including several beds in and around the highly polluted Chicago Sanitary District. In order to determine if populations of M. transversum from polluted sites exhibited any genetic response to the high levels of toxins and to examine the genetic structure of several populations of M. transversum for any changes due to the population crash, starch-gel electrophoresis was performed on M. transversum from three Illinois River localities and four Mississippi River basin locations. The sampled populations produced an inbreeding coefficient (FIS) of 0.929, indicating that the populations were highly inbred. The results of a suspected founder effect due to a bottleneck was suggested by an FST= 0.442. The isozyme Glucose-6-phosphate isomerase-2 (Gpi-2) produced allelic frequency patterns that were consistent with expected patterns of a pollution-tolerant allele. Polluted sites exhibited elevated frequencies of Gpi-2 100 whereas nonpolluted sites exhibited elevated frequencies of Gpi-2 74 . This frequency pattern suggested that natural selection was occurring in populations under severe toxic pressures, leading to an increase in the frequency of the allele Gpi-2 100 . Therefore, Gpi-2 100 is a possible pollution-tolerant mutation in M. transversum.
    Type of Medium: Electronic Resource
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  • 5
    ISSN: 1434-601X
    Keywords: PACS: 25.70.-z Low and intermediate energy heavy-ion reactions – 24.30.Cz Giant resonances – 23.20.-g Electromagnetic transitions – 25.70.Lm Strongly damped collisions
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract: We report on the results obtained from the study of the 32S +74Ge deep inelastic reaction at incident energy E= 320 MeV. High-energy γ-rays were detected in an array of 6 seven-pack BaF2 clusters. Coincidence with complex fragments detected in 12 three-stage telescopes ensured the selection of peripheral reaction events. In order to investigate the pre-equilibrium dipole strength excitation two independent analyses were performed. In the first analysis the energy spectra of the γ-rays were evaluated in the statistical model framework while in the second one the γ-ray fragment angular correlation with respect to the nuclear spin vector of the composite system was studied. Both methods indicate the excitation of dipole strength in the highly deformed dinucleus and provide dipole resonance parameter sets that are in good agreement with each other.
    Type of Medium: Electronic Resource
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  • 6
    ISSN: 1434-601X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract. For improved measurements of the key astrophysical reaction 12C(α,γ)16O in inverted kinematics, a recoil separator ERNA is being developed at the 4 MV Dynamitron tandem accelerator in Bochum to detect directly the 16O recoils with about 50% efficiency. Calculations of the ion beam optics including all filtering and focusing elements of ERNA are presented. Since the 12C projectiles and the 16O recoils have essentially the same momentum, and since the 12C ion beam emerging from the accelerator passes through a momentum filter (analysing magnet), the 12C ion beam must be as free as possible from 16O contamination for ERNA to succeed. In the present work, the 16O contamination was reduced from a level of 1 × 10−11 to a level below 2 × 10−29 by the installation of Wien filters both before and after the analysing magnet. The measurement of these and other beam specifications involved other parts of the final ERNA layout – sequentially a Wien filter, a 60˚ dipole magnet, another Wien filter, and a ΔE-E telescope. The setup led to a measured suppression factor of 5 × 10−18 for the 12C ion beam. The experiments also indicate that an almost free choice of the charge state for the 16O recoils is possible in the separator.
    Type of Medium: Electronic Resource
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  • 7
    ISSN: 1573-2568
    Keywords: roxatidine ; ranitidine ; MKN 28 ; cell proliferation ; cell migration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Gastric mucosal cell migration and proliferation are crucial events in the repair of gastric mucosal erosions. This study was designed to test the hypothesis that the H2 blockers roxatidine and ranitidine might stimulate migration and proliferation of gastric mucous cells derived from a human well-differentiated gastric adenocarcinoma cell line (MKN 28 cells)in vitro, in conditions independent of systemic factors and of acid inhibition. Confluent monolayers of MKN 28 cells were wounded with a razor blade and were then incubated with roxatidine or ranitidine. The number of cells migrating to the damaged area was determined 24 hr later. Cell proliferation was assessed by means of [3H]thymidine uptake and cell counts after incubation with roxatidine or ranitidine. Neither H2 antagonist significantly stimulated cell migration. On the other hand, cell proliferation was dose-dependently and significantly enhanced by incubation with roxatidine and ranitidine. Exogenous administration of TGF-α significantly stimulated MKN 28 cell division. However, incubation with roxatidine or ranitidine did not increase the steady-state mRNA expression of TGF-α or EGFR as assessed by northern blot analysis. Based on thesein vitro findings, we postulate that the ulcer healing effect of these H2 antagonistsin vivo might be due in part to stimulation of gastric mucosal cell proliferation.
    Type of Medium: Electronic Resource
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  • 8
    ISSN: 1573-0743
    Keywords: dobutamine stress echocardiography ; myocardial scintigraphy ; SPET ; Sestamibi ; pharmacological stress testing ; coronary artery disease
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Background: Simultaneous dobutamine stress echocardiography (DSE) and99mTc-MIBI-SPET (DMS) for the evaluation of the presence and the extent of coronary artery disease (CAD) were assessed for a head to head comparison regarding the diagnostic accuracy of the two tests. Methods and Results: Forty-five consecutive patients (33 males and 12 females: 53±6.8 yr.) underwent exercise electrocardiography and simultaneous dobutamine stress echocardiography and MIBI-SPET imaging. Coronary angiography was performed in all patients (significant coronary stenosis 〉 50%). On the basis of the results of exercise electrocardiogram the pre-test probability for coronary artery disease (Diamond's algorithm) was low (45.6±12.7 %). The overall specificity, sensitivity and predictive accuracy of Echo-dobutamine stress test for diagnosis of the presence or absence of CAD were: specificity 82%, sensitivity 76%, diagnostic accuracy 80%, positive predictive value 90%, negative predictive value 40%. The overall specificity, sensitivity and predictive accuracy of MIBI-SPET-dobutamine test for diagnosis of the presence or absence of CAD were: specificity 86%, sensitivity 87%, diagnostic accuracy 84%, positive predictive value 97%, negative predictive value 54%. MIBI-SPET-dobutamine test showed a significantly higher sensitivity in comparison with ECHO-dobutamine test (P〈0.05). Conclusion: Both noninvasive methods for the detection of CAD showed a good diagnostic accuracy. Nevertheless the SPET model showed an higher sensitivity in comparison with DSE model, essentially in the presence of a lower extent of CAD and during submaximal test.
    Type of Medium: Electronic Resource
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  • 9
    ISSN: 1439-0973
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Bei asymptomatischen, anti-HCV positiven Personen mit andauernd normalen oder leicht (das heißt ≤1,5 fach über der oberen Normgrenze) liegenden Serum ALT-Spiegeln wurden die HCV-RNA im Serum, Leberhistologie und das RIBA-II-Muster untersucht. Bei 22 asymptomatischen, anti-HCV positiven Personen (11 Männern und 11 Frauen im mittleren Alter von 40; Bereich 21–70 Jahren) wurde eine Leberbiopsie durchgeführt und HCV-RNA im Serum bestimmt. Der Nachweis von anti-HCV wurde mit ELISA-2 und RIBA-II-Tests geführt. Die HCV-RNA im Serum wurde mittels PCR bestimmt. Unsere Untersuchungen zeigten, 1.) daß 9/22 asymptomatischen, anti-HCV-positiven Personen histologische Zeichen einer chronischen Lebererkrankung mit fortbestehender HCV-Infektion hatten. 2.) Vier Personen hatten keine histologischen Zeichen einer chronischen Hepatitis und normale Serum-ALT-Spiegel trotz Nachweises von HCV-RNA im Serum. 3.) Die ALT-Spiegel im Serum unterschieden HCV-RNA positive Personen mit chronischer Hepatitis nicht von denjenigen ohne chronische Hepatitis. 4.) Bei anti-HCV positiven Personen mit normalen ALT-Spiegeln ist ein positiver RIBA-II Test nicht immer mit einer HCV-Virämie oder einer chronischen Hepatitis assoziiert. Bei unklarem RIBA-II-Muster bestanden häufig unspezifische Leberveränderungen oder ein normaler histologischer Befund. „Wirklich“ gesunde Träger von HCV (das heißt, Personen mit normalem Serum ALT-Spiegel, ohne histologische Zeichen einer chronischen Hepatitis trotz HCV Virämie) können folglich vorkommen.
    Notes: Summary This study was designed to evaluate serum HCV-RNA, liver histology, and RIBA-II pattern in asymptomatic anti-HCV positive subjects with persistently normal or slightly (i.e. ≤1.5 times the upper limit of the normal range) elevated serum ALT levels. To this purpose, 22 asymptomatic anti-HCV positive subjects (11 men and 11 women, median age 40, range 21–70 years) underwent liver biopsy and determination of serum HCV-RNA. Positivity for anti-HCV was determined by ELISA-2 and by RIBA-II. Serum HCV-RNA was determined by PCR. Our data show that: 1) 9/22 symptom-free, anti-HCV positive subjects had histological features of chronic liver disease associated with ongoing HCV infection; 2) four subjects had no histological signs of chronic hepatitis and normal serum ALT levels despite positivity for serum HCV-RNA; 3) serum ALT levels did not discriminate HCV-RNA positive subjects with from those without chronic hepatitis; 4) in anti-HCV positive subjects with normal serum ALT levels, a positive RIBA-II pattern was not always predictive of HCV viraemia or chronic hepatitis while an indeterminate RIBA-II pattern was frequently associated with nonspecific liver changes or normal histology. In conclusion, based on these findings, “true” healthy carriers of HCV (i.e. subjects with normal serum ALT levels and no histological features of chronic hepatitis despite HCV viraemia) may exist.
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    Springer
    Journal of comparative physiology 169 (1999), S. 303-310 
    ISSN: 1432-136X
    Keywords: Key words Corticosterone ; Testosterone ; Food-stress ; Nest-bound chicks
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract In this study we examined hormonal responses of Black-legged Kittiwake (Rissatridactyla) chicks to experimental variations in energy content and nutritional quality (low or high lipid to protein ratio, LPR) of their food. Starting at the age of 10 days, chicks were fed either high or low LPR fish at 30, 50, 70 and 100% of ad libitum energy intake. After 20 days of treatment, chicks were exposed to a standardized acute handling and restraint stress protocol, where a baseline sample was taken immediately after taking a chick from the nest, and three additional blood samples were taken at intervals up to 50 min. Testosterone and corticosterone titres in plasma were measured via radioimmunoassay. We found that baseline testosterone levels were not significantly affected by the experimental treatments. Food-restricted chicks had elevated baseline and acute stress-induced levels of corticosterone compared to chicks fed ad libitum. An elevation of circulating levels of corticosterone in energetically stressed individuals was further magnified by low nutritional quality of food. Baseline and acute stress-induced corticosterone levels of chicks were negatively correlated with their fat reserves. We conclude that the physiological condition of Black-legged Kittiwake chicks can be assessed reliably by measuring circulating levels of corticosterone. We discuss short- and long-term effects of elevated corticosterone secretion in food-stressed nest-bound chicks.
    Type of Medium: Electronic Resource
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