Showing papers by "University of Luxembourg published in 1998"

Spinocerebellar ataxia type 6: genotype and phenotype in German kindreds

Abstract: OBJECTIVE Spinocerebellar ataxia type 6 (SCA6) is an autosomal dominant cerebellar ataxia (ADCA) of which the mutation causing the disease has recently been characterised as an expanded CAG trinucleotide repeat in the gene coding for the α 1A -subunit of the voltage dependent calcium channel. The aim was to further characterise the SCA6 phenotype METHODS The SCA6 mutation was investigated in 69 German families with ADCA and 61 patients with idiopathic sporadic cerebellar ataxia and the CAG repeat length of the expanded allele was correlated with the disease phenotype. RESULTS Expanded alleles were found in nine of 69 families as well as in four patients with sporadic disease. Disease onset ranged from 30 to 71 years of age and was significantly later than in other forms of ADCA. Age at onset correlated inversely with repeat length. The SCA6 phenotype comprises predominantly cerebellar signs in concordance with isolated cerebellar atrophy on MRI. Non-cerebellar systems were only mildly affected with external ophthalmoplegia, spasticity, peripheral neuropathy, and parkinsonism. Neither these clinical signs nor progression rate correlated with CAG repeat length. CONCLUSIONS This study provides the first detailed characterisation of the SCA6 phenotype. Clinical features apart from cerebellar signs were highly variable in patients with SCA6. By comparison with SCA1, SCA2, and SCA3 no clinical or electrophysiological finding was specific for SCA6. Therefore, the molecular defect cannot be predicted from clinical investigations. In Germany, SCA6 accounts for about 13% of families with ADCA. However, up to 30% of SCA6 kindreds may be misdiagnosed clinically as sporadic disease due to late manifestation in apparently healthy parents. Genetic testing is therefore recommended for the SCA6 mutation also in patients with putative sporadic ataxia.

Overexpression of the Sarcolemmal Calcium Pump in the Myocardium of Transgenic Rats

Abstract: The plasma membrane calmodulin-dependent calcium ATPase (PMCA) is a calcium-extruding enzyme controlling Ca2+ homeostasis in nonexcitable cells. However, its function in the myocardium is unclear because of the presence of the Na+/Ca2+ exchanger. We approached the question of the physiological function of the calcium pump using a transgenic "gain of function" model. Transgenic rat lines carrying the human PMCA 4 cDNA under control of the ventricle-specific myosin light chain-2 promoter were established, and expression in the myocardium was ascertained at the mRNA, protein, and functional levels. In vivo hemodynamic measurements in adult homozygous animals showed no differences in baseline and increased cardiac performance recruited by volume overload compared with controls. No differences between transgenic and control cardiomyocytes were found in patch clamp voltage dependence, activation/inactivation behavior of the L-type Ca2+ current, or fast [Ca2+]i transients (assessed by the Fura-2 method). To test whether the PMCA might be involved in processes other than beat-to-beat regulation of contraction/relaxation, we compared growth processes of neonatal transgenic and control cardiomyocytes. A 1.6- and 2.3-fold higher synthesis rate of total protein was seen in cells from transgenic animals compared with controls on incubation with 2% FCS for 24 hours and 36 hours, respectively. An effect of similar magnitude was observed using 20 micromol/L phenylephrine. A 1.4-fold- and 2.0-fold-higher protein synthesis peak was seen in PMCA-overexpressing cardiomyocytes after stimulation with isoproterenol for 12 hours and 24 hours, respectively. Because pivotal parts of the alpha- and beta-adrenergic signal transduction pathways recently have been localized to caveolae, we tested the hypothesis that the PMCA might alter the amplitude of alpha- and beta-adrenergic growth signals by virtue of its localization in caveolae. Biochemical as well as immunocytochemical studies suggested that the PMCA in large part was colocalized with caveolin 3 in caveolae of cardiomyocytes. These results indicate that the sarcolemmal Ca2+-pump has little relevance for beat-to-beat regulation of contraction/relaxation in adult animals but likely plays a role in regulating myocardial growth, possibly through modulation of caveolar signal transduction.

An overview of descriptive studies in relation to a general design research methodology

Abstract: This paper describes a general design research methodology that aims at a more rigorous approach to design research by piecing together the various existing design research areas and by encouraging collaboration with other disciplines. It discusses the challenges involved in doing design research, such as the large number of factors that influence design, and highlights the importance of descriptive studies. The papers presented in this book are used throughout as examples, and set in the context of the proposed methodology in the Conclusion and Outlook at the end of this book. These papers and others revealed some of the key issues that need addressing: the formulation of criteria for success, the use of results from descriptive studies in the development of design methods and tools, and the validation of such methods and tools against these results.

Large torsion subgroups of split Jacobians of curves of genus two or three

Abstract: We construct examples of families of curves of genus 2 or 3 over Q whose Jacobians split completely and have various large rational torsion subgroups. For example, the rational points on a certain elliptic surface over P^1 of positive rank parameterize a family of genus-2 curves over Q whose Jacobians each have 128 rational torsion points. Also, we find the genus-3 curve 15625(X^4 + Y^4 + Z^4) - 96914(X^2 Y^2 + X^2 Z^2 + Y^2 Z^2) = 0, whose Jacobian has 864 rational torsion points. This paper has appeared in Forum Math. 12 (2000) 315-364.

Sugawara Construction and Casimir Operators for Krichever-Novikov Algebras

Abstract: We show how to obtain from highest weight representations of Krichever-Novikov algebras of affine type (also called higher genus affine Kac-Moody algebras) representations of centrally extended Krichever-Novikov vector field algebras via the Sugawara construction. This generalizes classical results where one obtains representations of the Virasoro algebra. Relations between the weights of the corresponding representations are given and Casimir operators are constructed. In an appendix the Sugawara construction for the multi-point situation is done.

“Still Stable after all This...?”: Temporal Comparison in Coping with Severe and Chronic Disease

Abstract: Temporal comparison theory is used as a conceptual framework for studying coping with life-threatening illness. Propositions derived from this theory were investigated in a questionnaire study on cancer patients (N = 100). Results reveal high rates of perceived change in the majority of the life domains included in the study, suggesting that consistency could not be maintained in most patients. Furthermore, a disproportion of perceived positive and negative life changes emerged, the latter being more prominent. Change perceptions were related to gender, age, and time elapsed since diagnosis. The relationships between positive and negative change on one hand and adjustment indicators on the other indicated that negative change correlated significantly whereas positive change was not associated with adjustment to illness.

Angiotensin converting enzyme inhibition modulates cardiac fibroblast growth.

Abstract: Background The progression of left ventricular hypertrophy and cardiac fibrosis in hypertensive heart disease is influenced by sex and age. Although angiotensin converting enzyme inhibition has been shown to prevent progression of the disease in postmenopausal women, the interaction of angiotensin II and estrogen in this process before and after the menopause is poorly understood. Objective To investigate the influence of the angiotensin converting enzyme inhibitor moexiprilat on serum, estrogen and angiotensin II-induced cardiac fibroblast growth. Methods Neonatal rat cardiac fibroblasts were incubated with 1 and 10% fetal calf serum, 10−7 mol/l angiotensin II, 10−9 mol/l estrone, 10–9 mol/l 17β-estradiol and 10−8 mol/l moexiprilat. Proliferation was measured in terms of incorporation of bromodeoxyuridine. Western blot analysis was performed using antibodies directed against the growth-related immediate early genes c-fos and Sp-1. All experiments were performed at least three times. Results Fetal calf serum stimulated cardiac fibroblast proliferation (1% fetal calf serum 2.0 ± 0.028-fold; 10% fetal calf serum 2.7 ± 0.028-fold). Angiotensin II and estrone stimulated proliferation of cardiac fibroblasts grown in the absence of fetal calf serum (angiotensin II 4.2 ± 0.075-fold; estrone 2.9 ± 0.034-fold) and further increased proliferation in the presence of 1% fetal calf serum (angiotensin II 4.3 ± 0.072-fold); (estrone 3.8 ± 0.045-fold) and 10% fetal calf serum (angiotensin II 4.8 ± 0.112-fold; estrone 4.1 ± 0.047-fold). Coincubation with moexiprilat specifically inhibited proliferation induced by angiotensin II and estrone but not by serum, and angiotensin II type 1 receptor blockade inhibited angiotensin II-induced but not estrone-induced cell growth. Western blot analysis showed that the expression of c-fos and Sp-1 was induced in a time-dependent fashion by angiotensin II (to maxima of 5.0-fold for c-fos and 3.0-fold for Sp-1) and estrone (15.2-fold for c-fos and 6.2-fold for Sp-1). This effect was completely inhibited by moexiprilat. Conclusions Angiotensin converting enzyme inhibition modulates cardiac fibroblast growth induced by angiotensin II and estrone. This mechanism might contribute to the beneficial effects of angiotensin converting enzyme inhibition in postmenopausal patients with hypertensive heart disease. J Hypertens 16:377–384 © 1998 Rapid Science Ltd.

Deconstruction, justice and the question of education

Abstract: Zeitschrift fur Erziehungswissenschaft 1 (1998) 3, S. 395-411 Padagogische Teildisziplin: Allgemeine Erziehungswissenschaft; als elektronischer Volltext verfugbar

Psychological factors associated with the uptake of measles immunization: findings and implications for prevention.

Abstract: A cross-sectional study of 8204 children was performed to investigate the prevalence of immunization against measles, mumps and rubella and possible determinants of immunization uptake. The study was approached from a Lewinian perspective on preventive behaviour. Seventy-one questions referring to the guardian of the child, his or her partner, the household and the child, as well as to immunization-related experiences and situational topics were asked. Two psychological variables were studied: health locus of control and subjective relevance concerning measles. The immunization rate was 77.7 percent [95 percent confidence interval 76.8-78.6]. Multiple logistic regression yielded the following odds ratios for non- uptake of measles immunization: natural health orientation 8.74 [6.72-11.37]; advice of paediatrician 6.02 [4.67-7.75]; dangerousness of measles 2.00 [1.53-2.60]; marital status 1.87 [1.31-2.51]; assessed reliability of vaccination 1.57 [1.23-2.01]; smoking 1.55 [1.21-1.98]; and number of sibling...

Kant und das Problem des metaphysischen Idealismus

Abstract: In der Reihe werden herausragende monographische Untersuchungen zu allen Aspekten der Philosophie Kants veroffentlicht, ebenso zum systematischen Verhaltnis seiner Philosophie zu anderen philosophischen Ansatzen in Geschichte und Gegenwart Veroffentlicht werden Studien, die einen innovativen Charakter haben und ausdruckliche Desiderate der Forschung erfullen Die Publikationen reprasentieren damit den aktuellsten Stand der Forschung"

Polizei und Fremde: Belastungssituationen und die Genese von Feindbildern und Übergriffen

Abstract: Im Oktober 1994 hatte der „Arbeitskreis II“ der Innenministerkonferenz ein Forschungsprojekt angeregt, das sich mit spezifischen Ursachen und Ausdrucksformen von Rassismus und Fremdenfeindlichkeit innerhalb der Polizei befassen sollte. Mit der Vergabe und Betreuung des Forschungsvorhabens wurde die Polizei-Fuhrungsakademie (PFA) in Munster-Hiltrup beauftragt. Das praktische Ziel der durchzufuhrenden Studie sollte es sein, „die Polizei besser auf die Kontakte und auch Konflikte mit Burgern auslandischer Herkunft vorzubereiten1. Als eine wesentliche Informationsbasis fur solche Vorschlage wurden die Alltagserfahrungen, Sichtweisen und Einstellungen der unmittelbar betroffenen Polizeibeamtinnen und -beamten angesehen. Um diese zu erkunden, wurden im Fruhjahr 1995 verschiedene Workshops (Arbeitstagungen mit Seminarcharakter) konzipiert und durchgefuhrt. Ziel dieser Workshops war es nicht, quantitative Aussagen uber die Verbreitung von auslanderfeindlichen Einstellungen, Ubergriffen und Straftaten innerhalb der Polizei zu treffen. Dazu ware eine aufwendige Dunkelfeldforschung notwendig gewesen, fur die die Mittel nicht bereit standen. In den Workshops sollten vielmehr jene Bedingungen, Situationen und Konfliktfelder in der Polizeiarbeit ermittelt werden, durch die fremdenfeindliche Einstellungen, Emotionen und Handlungsweisen moglicherweise entstehen, sich verfestigen und zuspitzen konnen.

The literature workbook

Abstract: Acknowledgements. Using this book. 1. Miniature Poems: Reading the Elizabethan Sonnet as a Jewel 2. What's Syntax Got to do with Poetry?: On Puritan Mind-Style and Romantic World-View 3. Women's Poetry: Same or Different? 4. Death on Stage: Learning to Die in a Revenge Tragedy 5. Sheridan's School for Marriage: The Effect of Education and the Nature of Comedy 6. Degenerate Apemen or Heroic Dreamers?: On Cultural Stereotypes and Synges's The Playboy of the Western World 7. Talking About the Weather: Emma and the Social Web of Dialogue 8. Of Elephants, Serpents and Fairy Palaces: Simile and Metaphor in Dickens' Hard Times 9. Laughter in Patriarchy and Colonialism: Lexical Repetition and Jean Rhys' Wide Sargasso Sea 10. Point of View and its Effects: Resisting Brian Moore's Lies of Silence Glossary. Index.

Premier et deuxième espaces de cohomologie de l'algèbre de lié des opérateurs différentiels sur une variété, a coefficients dans les fonctions

Abstract: In [5], we constracted a geveral method, which allowed us to show that the first and econd term of the local Chevalley-Eilenberg cohomology of the algebra of differential operator on a manifold, with coefficients in the space of functions, are isomorphic to the corresponding spaces of the de Rhan cohomology. It now will be proved, by the same method, that this result also holds for the third cohomology spaces.

Les composantes de l'intelligence générale du D70

Abstract: La validite du D70 en tant que test d'intelligence generale est evaluee dans cette recherche. Dans une premiere etude, on a montre que lorsque le D70 est applique avec d'autres tests d'intelligence, l'analyse factorielle confirmatoire, ainsi que le modele d'echelonnement multidimensionnel le situent bien a la place qui revient aux tests d'intelligence generale. L'analyse theorique des items du test a degage deux facettes comme source de variation potentielle de la difficulte des items: le format de presentation et la nature des regles. Dans une deuxieme recherche, ou le test a ete applique sous une version micro-informatique, la validite de ces parametres est evaluee et on a trouve que seule la nature des regles influence la performance et les temps de reponse. Quatre principes de construction des items sont reconnus comme source de variation : les items a regles spatiale, mixte, numerique et arithmetique. Lorsqu'on decompose le test en fonction de ces principes de construction et qu'on introduit les composantes dans des analyses structurales, les items a regles numerique ou arithmetique apparaissent comme centraux, mais non les items a regle spatiale ou mixte.