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Reavy B, Ziegler A, Diplexcito J, Macintosh SM, Torrance L, Mayo M. Expression of functional recombinant antibody molecules in insect cell expression systems. Protein Expr Purif 2000; 18:221-8. [PMID: 10686153 DOI: 10.1006/prep.1999.1191] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Recombinant single-chain variable-fragment molecules (scFv) were constructed from a cell line expressing a monoclonal antibody against African cassava mosaic virus (ACMV) and expressed in Escherichia coli. DNA sequences that encoded the scFv were manipulated to allow scFv expression in insect cell lines. A recombinant baculovirus containing the scFv cDNA was constructed and large amounts of scFv were produced in each of three insect cell lines infected with the baculovirus. However, the scFv were not secreted into the medium by any of the cell lines despite the scFv having been linked to a honeybee melittin leader sequence. The same scFv cDNA construct was introduced into Drosophila DS2 cells and a stable recombinant cell line was obtained that produced scFv that was secreted into the medium. Culture medium containing the scFv was used directly in enzyme-linked immunosorbent assay (ELISA) tests to detect ACMV in plant tissues. Another construct that encoded the Ckappa domain of human IgG was fused to the C-terminus of the scFv that was produced and expressed in Drosophila cells. This scFv derivative also accumulated in the medium and was more active in ELISA than scFv lacking the Ckappa domain.
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Ziegler A. Sampling strategies for model free linkage analyses of quantitative traits: implications for sib pair studies of reading and spelling disabilities to minimize the total study cost. Eur Child Adolesc Psychiatry 2000; 8 Suppl 3:35-9. [PMID: 10638367 DOI: 10.1007/pl00010691] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
One approach to establish linkage is based on allele sharing methods for sib pairs. In recent years the use of selected sib pairs to increase power for mapping quantitative traits in humans has been discussed intensively. In this paper the different basic principles for sib pair sampling proposed in the literature are made evident. Implications for ascertainment schemes of sib pairs to minimize the total study cost in linkage analyses on reading and spelling disabilities are discussed.
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von Kienlin M, Ziegler A, Le Fur Y, Rubin C, Dećorps M, Rémy C. 2D-spatial/2D-spectral spectroscopic imaging of intracerebral gliomas in rat brain. Magn Reson Med 2000; 43:211-9. [PMID: 10680684 DOI: 10.1002/(sici)1522-2594(200002)43:2<211::aid-mrm7>3.0.co;2-a] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
1H-MR spectroscopy in vivo is often hampered by poor spectral resolution. Spectral overlap can be avoided with two-dimensional spectroscopic techniques. Correlation peak imaging has been implemented to measure unambiguously the distribution of several metabolites in a rat brain glioma model. Acquisition-weighted spectroscopic imaging reduced the experimental time and provided excellent spatial localization. The choice of an appropriate spectral acquisition window granted good sensitivity. Spectroscopic images presenting a full two-dimensional spectrum in every image pixel were acquired in seven rats at 7 Tesla in 195 min, with a nominal voxel volume of 75 microl. Among other metabolites, the distribution of hypotaurine, phosphoethanolamine, alanine, and even glucose could be visualized both in the C6-glioma and in the unaffected brain.
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279
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Oeffner F, Bornholdt D, Ziegler A, Hinney A, Görg T, Gerber G, Goldschmidt HP, Siegfried W, Wright A, Hebebrand J, Grzeschik KH. Significant association between a silent polymorphism in the neuromedin B gene and body weight in German children and adolescents. Acta Diabetol 2000; 37:93-101. [PMID: 11194934 DOI: 10.1007/s005920070026] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Neuromedin B has been shown to exert an inhibiting effect on food consumption in rats. The corresponding gene NMB maps to chromosome 15q22.3-q23, a region expected to contain a gene for the Bardet-Biedl syndrome type 4 (BBS4). Based on its map position and the putative function of the encoded peptide, NMB can be considered as a candidate gene both for BBS4 and the development of human obesity. To examine its involvement in these phenotypes, we determined the genomic structure of human NMB, and performed a mutation screen in its coding region. In genomic DNA of six BBS4 patients and in a large population sample, two sequence variants were detected: a g.253C-->A transversion creating a P73T substitution and a g.401G-->A silent mutation changing the stop codon TGA into stop codon TAA. A case-control study with 92 extremely obese patients and 94 underweight students revealed a significant association between the g.401G-->A polymorphism and body weight (adjustedp = 0.03), which was confirmed in a validation sample consisting of 95 extremely obese patients, and 95 normal weight and 48 underweight individuals (Mann-Whitney p = 0.02). These results suggest a contribution of NMB or a gene in its close vicinity to genetic weight control in humans.
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280
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Frey J, Hebebrand J, Müller B, Ziegler A, Blum WF, Remschmidt H, Herpertz-Dahlmann BM. Reduced body fat in long-term followed-up female patients with anorexia nervosa. J Psychiatr Res 2000; 34:83-8. [PMID: 10696835 DOI: 10.1016/s0022-3956(99)00038-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
We aimed to evaluate both body composition and serum leptin levels in females with a past history of anorexia nervosa (AN) adjusted for their current body mass index (BMI). Twenty-three females with a past history of AN were followed-up 10 years after inpatient treatment and compared to 23 female controls of a similar age range matched for BMI on a one to one basis. Serum leptin levels were assessed and percent body fat (%BF) was determined via bioelectric impedance analysis. Differences of both %BF and leptin levels between cases and controls were tested under the hypothesis that cases have lower %BF and lower serum leptin levels than the controls. %BF was indeed lower in the cases compared to the controls (p < 0.05). However, differences in leptin levels between both groups just failed significance (p = 0.051). We conclude that body composition differs between long-term followed-up patients with AN and BMI- and gender-matched controls. Based on the finding that the former patients reported being more physically active, we assume that the higher physical activity levels in recovered patients with AN underlie the lower %BF.
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Ziegler A, Hebebrand J, Kastner C, Müller-Myhsok B. Significant evidence for linkage of a simulated trait to D1G024--a conclusion reached using multiallelic transmission/disequilibrium tests. Genet Epidemiol 1999; 17 Suppl 1:S785-9. [PMID: 10597531 DOI: 10.1002/gepi.13701707129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
We applied three versions of the transmission/disequilibrium test (TDT) for detecting linkage in nuclear families using the a priori information of possibly present association. For our analyses we employed all marker data for a simulated trait. Results for replicate 11 showed significant linkage to D1G024 using the multiallelic Tmhet statistic and the extended TDT. The TDT for the most frequent parental allele which had been applied successfully in previous studies failed to detect linkage. This result may have happened because the data did not arise from a realistic simulation of the evolution of a real population, where mutations might be expected to occur against a specific haplotype. Simulation studies are required to elucidate the applicability of the TDT for the most frequent parental allele in realistic situations. Furthermore, guidelines have to be developed for how to pool categories in large, sparse contingency tables to obtain larger cell frequencies and lower degrees of freedom.
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282
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Hinney A, Schneider J, Ziegler A, Lehmkuhl G, Poustka F, Schmidt MH, Mayer H, Siegfried W, Remschmidt H, Hebebrand J. No evidence for involvement of polymorphisms of the dopamine D4 receptor gene in anorexia nervosa, underweight, and obesity. AMERICAN JOURNAL OF MEDICAL GENETICS 1999; 88:594-7. [PMID: 10581473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
Family and twin studies suggest a genetic contribution to the etiology of anorexia nervosa (AN) and obesity. Genes involved in weight regulation can be considered as candidate genes for AN. The dopaminergic system has been implicated in weight regulation; previous results had suggested a possible involvement of the dopamine D4 receptor gene (DRD4). We screened for alleles of two different polymorphisms (13-bp deletion, 48-bp repeat) in the DRD4. For association tests, allele frequencies were compared between 109 inpatients with AN, 82 underweight students, and 327 extremely obese children and adolescents. For application of transmission disequlibrium tests (TDT) we additionally genotyped 57 and 137 trios comprising a patient with AN or an extremely obese child or adolescent, respectively, and both parents. All genotyping was performed with polymerase chain reaction fragment length polymorphism analyses. None of the association tests or TDT rendered nominal P values below 0.1. An influence of alleles of the DRD4 on the development of AN, underweight, or extreme early onset obesity was not detected. Am. J. Med. Genet. (Neuropsychiatr. Genet.) 88:594-597, 1999.
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283
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Grand S, Passaro G, Ziegler A, Estève F, Boujet C, Hoffmann D, Rubin C, Segebarth C, Décorps M, Le Bas JF, Rémy C. Necrotic tumor versus brain abscess: importance of amino acids detected at 1H MR spectroscopy--initial results. Radiology 1999; 213:785-93. [PMID: 10580954 DOI: 10.1148/radiology.213.3.r99dc10785] [Citation(s) in RCA: 113] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE To assess the usefulness of the 0.9-ppm peak from amino acids (-CH3 moieties from valine, leucine, and isoleucine) for the differentiation of brain abscesses and tumors at in vivo hydrogen 1 magnetic resonance (MR) spectroscopy. MATERIALS AND METHODS Amino acid concentrations were determined in vitro in 13 purulent samples from brain and nonbrain tissues and in nine aseptic fluids from necrotic brain tumors at two-dimensional (2D) 1H MR spectroscopy and liquid chromatography. Thirty-four patients with cystic intracerebral mass lesions (28 tumors, six abscesses) were examined at 1H MR spectroscopy in vivo. RESULTS Amino acids were identified in vitro in both purulent and aseptic samples. Amino acid concentrations measured in the aseptic fluids at both liquid chromatography and 2D MR spectroscopy were far below the detection threshold of in vivo 1H MR spectroscopy. Quantitative results obtained at 2D MR spectroscopy showed no overlap in the ranges of amino acid concentrations in purulent and aseptic samples. In vivo, the proton spectra obtained with a 136-msec echo time (TE) revealed amino acids (inverted peak at 0.9 ppm) in only the abscesses. CONCLUSION The detection of amino acid resonance at 0.9 ppm at in vivo 1H MR spectroscopy (136-msec TE) is a promising tool for distinguishing bacterial abscesses and cystic brain tumors.
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284
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Roloff T, Holtfoht A, Ziegler A, Heinzl S. [Oxazolidinones. A new anti-infective principle]. MEDIZINISCHE MONATSSCHRIFT FUR PHARMAZEUTEN 1999; 22:370-5. [PMID: 10628146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
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285
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Ziegler A, Simões-Wuest AP, Zangemeister-Wittke U. Optimizing efficacy of antisense oligodeoxynucleotides targeting inhibitors of apoptosis. Methods Enzymol 1999; 314:477-90. [PMID: 10565033 DOI: 10.1016/s0076-6879(99)14123-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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286
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Stegmann K, Ziegler A, Ngo ET, Kohlschmidt N, Schröter B, Ermert A, Koch MC. Linkage disequilibrium of MTHFR genotypes 677C/T-1298A/C in the German population and association studies in probands with neural tube defects(NTD). AMERICAN JOURNAL OF MEDICAL GENETICS 1999; 87:23-9. [PMID: 10528242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
A number of studies have demonstrated that the common polymorphism 677C-->T in the gene encoding 5, 10-methylenetetrahydrofolate reductase (MTHFR) leads to a thermolabile variant with decreased enzyme activity and to mildly elevated plasma homocysteine. 677TT homozygosity was shown to be more frequent in NTD probands compared with controls in some studies. Recently, another polymorphism, 1298A-->C, in the MTHFR gene was described and combined heterozygosity 677CT/1298AC was suggested to be an additional risk factor for NTD. The present study examines the genotype and haplotype distribution of the two polymorphisms in the German population and evaluates the impact on NTD individuals and their relatives. To determine the haplotype of all individuals tested, we developed an easy-to-perform ARMS-RFLP test. Our data show that the two polymorphisms are in linkage disequilibrium in the general population and in NTD individuals. There was no statistically significant difference in allele and genotype frequency between probands (patients, fetuses) and controls (P > 0.10) and between observed and expected values for mother-child pairs (P > 0.80). Taking into account gender, an increased rate of 677CT heterozygotes was found in affected and unaffected males compared to affected and unaffected females. A family-based association study using a multiallelic transmission disequilibrium test (TDT) also shows that transmission rates do not deviate significantly from equilibrium (P > 0.50). Thus, our data provide no evidence for an association between NTD phenotype and MTHFR 677C/T-1298A/C genotypes and haplotypes.
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287
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Ziegler A, Merz E. Membrane particle distribution in the sternal epithelia of the terrestrial isopod Porcellio scaber latr. (Crustacea, oniscidea) during CaCO(3) deposit formation and resorption, a freeze-etch analysis. J Struct Biol 1999; 127:263-78. [PMID: 10544052 DOI: 10.1006/jsbi.1999.4166] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The anterior sternal epithelium of terrestrial isopods transports cuticular Ca(2+) to and from large sternal CaCO(3) deposits. We analyzed the anterior and posterior sternal epithelium by the means of the freeze-etch technique and measured the size distribution and density of intramembrane particles (IMPs) during three different molting stages. At least three IMP size classes around 4.5, 7.7, and 9.4 nm can be distinguished on the P-face of the apical and basolateral plasma membrane. An additional size class of around 12.8 nm is restricted to the apical compartment. In the anterior sternal epithelium, the density of these large particles changes by a factor of 1.9 during the molt cycle, suggesting a role in CaCO(3) formation and/or resorption. The density of the smaller IMPs rises transiently by a factor of 1.3 in the posterior sternal epithelium only. The IMP density of the basolateral plasma membrane increases significantly by a factor of 1.4 and 1.3 in the anterior and posterior sternal epithelia, respectively. The results indicate that increases in the IMP density contribute to the differentiation to an increased transport activity during the cyclic enlargements of the plasma membrane surface area in the anterior sternal epithelium.
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288
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Ziegler A, Hebebrand J, Görg T, Rosenkranz K, Fichter M, Herpertz-Dahlmann B, Remschmidt H, Hinney A. Further lack of association between the 5-HT2A gene promoter polymorphism and susceptibility to eating disorders and a meta-analysis pertaining to anorexia nervosa. Mol Psychiatry 1999; 4:410-2. [PMID: 10523809 DOI: 10.1038/sj.mp.4000561] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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289
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Braun-Dullaeus RC, Mann MJ, Ziegler A, von der Leyen HE, Dzau VJ. A novel role for the cyclin-dependent kinase inhibitor p27(Kip1) in angiotensin II-stimulated vascular smooth muscle cell hypertrophy. J Clin Invest 1999; 104:815-23. [PMID: 10491417 PMCID: PMC408428 DOI: 10.1172/jci5339] [Citation(s) in RCA: 105] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/1998] [Accepted: 08/04/1999] [Indexed: 12/26/2022] Open
Abstract
Angiotensin II (Ang II) has been shown to stimulate either hypertrophy or hyperplasia. We postulated that the differential response of vascular smooth muscle cells (VSMCs) to Ang II is mediated by the cyclin-dependent kinase (Cdk) inhibitor p27(Kip1), which is abundant in quiescent cells and drops after serum stimulation. Ang II treatment (100 nM) of quiescent VSMCs led to upregulation of the cell-cycle regulatory proteins cyclin D1, Cdk2, proliferating cell nuclear antigen, and Cdk1. p27(Kip1) levels, however, remained high, and the activation of the G1-phase Cdk2 was inhibited as the cells underwent hypertrophy. Overexpression of p27(Kip1) cDNA inhibited serum-stimulated [(3)H]thymidine incorporation compared with control-transfected cells. This cell-cycle inhibition was associated with cellular hypertrophy, as reflected by an increase in the [(3)H]leucine/[(3)H]thymidine incorporation ratio and by an increase in forward-angle light scatter during flow cytometry at 48 hours after transfection. The role of p27(Kip1) in modulating the hypertrophic response of VSMCs to Ang II was further tested by antisense oligodeoxynucleotide (ODN) inhibition of p27(Kip1) expression. Ang II stimulated an increase in [(3)H]thymidine incorporation and the percentage of S-phase cells in antisense ODN-transfected cells but not in control ODN-transfected cells. We conclude that p27(Kip1) plays a role in mediating VSMC hypertrophy. Ang II stimulation of quiescent cells in which p27(Kip1) levels are high results in hypertrophy but promotes hyperplasia when levels of p27(Kip1) are low, as in the presence of other growth factors.
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290
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Hempelmann RG, Pradel RH, Mehdorn HM, Ziegler A. Threshold concentrations of endothelin-1: the effects on contractions induced by 5-hydroxytryptamine in isolated rat cerebral and mesenteric arteries. PHARMACOLOGY & TOXICOLOGY 1999; 85:115-22. [PMID: 10522750 DOI: 10.1111/j.1600-0773.1999.tb00077.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
This study compares the effects of threshold concentrations of endothelin-1 in isolated rat basilar arteries with those in mesenteric arterial branches and investigates the mechanisms of inhibitory and potentiating endothelin-1-effects. In basilar arteries, endothelin-1 reduces the contractions induced by 5-hydroxytryptamine (5-HT), by the thromboxane A2 agonist U46619, and by vasopressin. The inhibitory effect of endothelin-1 on the contraction induced by 5-HT is abolished by deendothelialization, by the endothelin ET(B) receptor antagonist RES 701-1, by indomethacin, or by glibenclamide. In mesenteric arteries, endothelin-1 potentiates the contractile effects of 5-HT, U46619, and vasopressin. The potentiation of the contractile effect induced by 5-HT is only somewhat modified by deendothelialization, but abolished by the thromboxane A2 receptor antagonists GR32191 and ridogrel. U46619 potentiates the 5-HT-effect in mesenteric arteries. Thus, though the contractile endothelin ET(A) receptors were not blocked, threshold concentrations of endothelin-1 inhibited contractile effects in the rat basilar artery via activation of endothelial ET(B) receptors. Prostaglandins and ATP-sensitive K+ channels are involved in this inhibitory action. In contrast, endothelin-1 potentiates contractile actions in mesenteric arteries via the release of endogeneous thromboxane A2 from non-endothelial cells. The study points out the completely different role of the endothelium in combined effects of endothelin-1 between cerebral and mesenteric arteries.
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291
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Sander T, Peters C, Kämmer G, Samochowiec J, Zirra M, Mischke D, Ziegler A, Kaupmann K, Bettler B, Epplen JT, Riess O. Association analysis of exonic variants of the gene encoding the GABAB receptor and idiopathic generalized epilepsy. AMERICAN JOURNAL OF MEDICAL GENETICS 1999; 88:305-10. [PMID: 10402495 DOI: 10.1002/(sici)1096-8628(19990820)88:4<305::aid-ajmg5>3.0.co;2-x] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The gene encoding the GABAB receptor (GABABR1) maps close to the HLA-F locus on chromosome 6p21.3 in the same region to which a major susceptibility locus for common subtypes of idiopathic generalized epilepsy (IGE), designated as EJM1, has been localized. Moreover, animal models suggest that the GABAB receptor plays a critical role in the epileptogenesis of absence seizures. Accordingly, the present association study tested the candidate gene hypothesis that genetic variants of the human GABABR1 gene confer susceptibility to common subtypes of IGE. Three DNA sequence variants in exons 1a1, 7, and 11 of the GABABR1 gene were assessed by PCR-based restriction fragment length polymorphisms in 248 unrelated probands of German descent, comprising 72 patients with juvenile myoclonic epilepsy (JME), 46 patients with idiopathic absence epilepsy (IAE), and 130 control subjects without a history of epileptic seizures and lack of generalized spike-wave discharges in their electroencephalogram. The results revealed no evidence for an allelic association of any of the GABABR1 sequence variants with either JME or IAE (P > 0.18). Thus, we failed to demonstrate that any of the three exonic GABABR1 variants themselves, or other so-far unidentified mutations, which are in strong linkage disequilibrium with the investigated variants, are involved in the pathogenesis of common IGE subtypes.
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292
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Abstract
To revive the appreciation of the importance of genetic studies for the understanding of neurologic diseases inherited in a monogenic fashion. After a description of the basic patterns of monogenic inheritance, the importance of linkage studies for the mapping of a disease gene is mentioned. Furthermore, the term linkage disequilibrium is introduced. Finally, several procedures used in current linkage analyses are briefly mentioned, with the aim of identifying the disease gene. The importance of genetic studies of disease families with many members, preferably from isolated surroundings to favor homogeneity, is stressed. However, such analyses can be performed only as a consequence of a close cooperation between clinicians and research scientists.
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293
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Sol MA, Vacaresse N, Lule J, Davrinche C, Gabriel B, Teissie J, Ziegler A, Thomsen M, Benoist H. N-linked oligosaccharides can protect target cells from the lysis mediated by NK cells but not by cytotoxic T lymphocytes: role of NKG2-A. TISSUE ANTIGENS 1999; 54:113-21. [PMID: 10488737 DOI: 10.1034/j.1399-0039.1999.540201.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
We have previously shown that glycophorin A (GPA), inserted by electropulsation into the membrane of K562 cells, protected them from natural killer (NK) cell-mediated cytotoxicity and the unique N-linked oligosaccharide of GPA was essential for resistance to occur. The present study demonstrates that the protection level conferred by GPA is similar to the resistance induced by HLA-Cw3 expressed by transfected K562 cells. A monoclonal antibody against NKG2-A, an NK inhibitory receptor interacting with HLA class I antigens and belonging to the C-type lectin receptor, was able to restore the ability of NK cells to lyse K562 cells expressing HLA-Cw3 at the cell membrane but not electroinserted-GPA, suggesting that the N-linked oligosaccharide of GPA cannot be a ligand for NKG2-A. GPA was then electroinserted into the membrane of two lymphoblastoid B-cell lines: one was sensitive to NK cell-mediated lysis, the other was susceptible to cytotoxic CD8+ T-lymphocyte (CTL)-mediated cytotoxicity. The electroinserted GPA protected the target cells from NK-mediated cytotoxicity, whereas it did not modify the cell susceptibility to lysis by CTL. Endoglycosidase F treatment abolished the resistance towards NK cell-mediated lysis, suggesting that N-linked glycans could inhibit mechanisms used by NK cells to exert their cytotoxic function in agreement with our previous results.
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294
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Hinney A, Herrmann H, Löhr T, Rosenkranz K, Ziegler A, Lehmkuhl G, Poustka F, Schmidt MH, Mayer H, Siegfried W, Remschmidt H, Hebebrand J. No evidence for an involvement of alleles of polymorphisms in the serotonin1Dbeta and 7 receptor genes in obesity, underweight or anorexia nervosa. Int J Obes (Lond) 1999; 23:760-3. [PMID: 10454111 DOI: 10.1038/sj.ijo.0800926] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The serotonergic (5-hydroxytryptamine, 5-HT) system has been implicated in body weight regulation and in the etiology of anorexia nervosa (AN). Here we describe the screening of the known Phe-124-Cys polymorphism in the 5-HT1Dbeta receptor gene and of the known Pro-279-Leu polymorphism in the 5-HT7 receptor gene. For association tests allele frequencies were compared between up to 393 extremely obese children and adolescents, 142 underweight students and 84 patients with AN. None of the association tests revealed nominal P-values below 0.3. We conclude that a major role of the investigated polymorphisms in body weight regulation or AN appears unlikely.
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295
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Janitz K, Wild A, Beck S, Savasta S, Beluffi G, Ziegler A, Volz A. Genomic organization of the HSET locus and the possible association of HLA-linked genes with immotile cilia syndrome (ICS). Immunogenetics 1999; 49:644-52. [PMID: 10369922 DOI: 10.1007/s002510050660] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The kinesin-related protein (HSET) gene belongs to the kinesin superfamily, the members of which are involved in cellular transport processes. The HSET gene product was previously characterized by partial cDNA sequencing. The gene is located on the short arm of human Chromosome 6 (6p21.3), at the centromeric end of the major histocompatibility complex. Here, we report the genomic structure of the complete HSET gene together with its flanking loci. Sequence analysis of the 40 kilobase (kb) cosmid clone containing the HSET gene also revealed the presence of several new genes not related to the kinesin superfamily. These include a 60S ribosomal protein L35A-like pseudogene (rPL35A-like) on the telomeric side and a polycomb-like gene (PHF1), a copper tolerance-like gene (CUTA1) and the 5' part of the synaptic ras-GTPase-activating protein (SynGAP) gene centromeric of HSET. In addition, a complete 60S ribosomal protein L12-like (rPL12L) gene in intron 3 of the HSET gene was identified which appears to have an open reading frame. The possible involvement of the HSET gene and a beta-tubulin gene (TUBB) in the pathogenesis of immotile cilia syndrome (ICS) was studied by screening two unrelated ICS families with microtubular defects and suspected HLA linkage for mutations within the HSET gene and the TUBB gene. Four single base substitutions were detected in the HSET gene, and none in the TUBB gene. On the basis of these data, a role of the HSET and TUBB products in the pathogenesis of ICS in the two families is unlikely.
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296
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Kober F, Wolf PE, Leviel JL, Vermeulen G, Duhamel G, Delon A, Derouard J, Décorps M, Ziegler A. Low-temperature polarized helium-3 for MRI applications. Magn Reson Med 1999; 41:1084-7. [PMID: 10371438 DOI: 10.1002/(sici)1522-2594(199906)41:6<1084::aid-mrm2>3.0.co;2-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The first 3He nuclear magnetic resonance (NMR) experiments using low-temperature prepolarization are presented. 3He cells were polarized at 4.2 K and 4.7 T, transported to another magnet, heated to room temperature, and used for NMR experiments at 2.35 T. Cells with and without a rubidium coating were tested. In both cases, the NMR signal was greater than 100 times the thermal equilibrium signal. No evidence of a rubidium coating effect on the longitudinal relaxation time T1 of 3He (500 mbar) at 4.2 K could be demonstrated. NMR gradient-echo images of the cells were acquired.
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Kober F, Koenigsberg B, Belle V, Viallon M, Leviel JL, Delon A, Ziegler A, Décorps M. NMR imaging of thermally polarized helium-3 gas. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 1999; 138:308-312. [PMID: 10341135 DOI: 10.1006/jmre.1999.1756] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
It is shown that thermally polarized 3He gas can be used to measure important physical parameters and to design, test, and tune imaging sequences. The bulk values of T1, T2, and the diffusion coefficient were measured in a glass cell containing a mixture of helium-3 (0.8 bar) and oxygen (0.2 bar). They were found to be T1 = 7 s, T2 = 2.4 s, and D = 1.6 cm2 s(-1). The relaxation times T2* and T1 and the apparent diffusion coefficient of thermally polarized helium-3 gas were measured in the rat lung, and these parameters were used to design a helium-3 optimized multi-spin-echo sequence which was shown to increase the signal-to-noise ratio sufficiently to obtain the first NMR-images of thermally polarized helium-3 in the rat lung.
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298
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Datté JY, Ziegler A, Tillement JP. Sympathomimetic effects of Parquetina nigrescens (Periplocaceae) extract in isolated portal vein smooth muscle. GENERAL PHARMACOLOGY 1999; 32:551-6. [PMID: 10382856 DOI: 10.1016/s0306-3623(98)00205-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
The purpose of this study was to examine the mechanisms underlying the pharmacological effects of the extract of Parquetina nigrescens (Expar) on vascular smooth muscle contractility. To evaluate the Expar effect, the contractile activity of portal veins isolated from Wistar Kyoto rats was isometrically recorded. Isolated portal vein preparations developed rhythmic and spontaneous contractile activity. Expar increased the contractile response of the portal vein preparations in a dose-dependent manner. The maximal effect of the dose-response curve for Expar was prevented by the alpha1-adrenergic blocking agent prazosin at 10 nM and 30 nM concentration dependently. The contractile responses of the muscle to Expar were partly blocked after chemical sympathectomy of the preparations with 6-hydroxydopamine, and those obtained in the same conditions with tyramine were completely abolished, whereas responses to noradrenaline were unaffected by the 6-hydroxydopamine pretreatment. It is concluded that Expar contains principles, which can be characterized as direct and indirect sympathomimetic.
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299
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Hinney A, Schmidt A, Nottebom K, Heibült O, Becker I, Ziegler A, Gerber G, Sina M, Görg T, Mayer H, Siegfried W, Fichter M, Remschmidt H, Hebebrand J. Several mutations in the melanocortin-4 receptor gene including a nonsense and a frameshift mutation associated with dominantly inherited obesity in humans. J Clin Endocrinol Metab 1999; 84:1483-6. [PMID: 10199800 DOI: 10.1210/jcem.84.4.5728] [Citation(s) in RCA: 259] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The melanocortin-4 receptor gene (MC4-R) has been implicated in weight regulation. Recently, two independent groups reported frameshift mutations associated with a dominant form of obesity (1, 2). We screened the coding region of the MC4-R in 306 extremely obese children and adolescents (mean body mass index: BMI 34.4 +/- 6.6 kg/m2), 25 healthy underweight students (mean BMI 17.1 +/- 0.8 kg/m2), 52 normal weight individuals (mean BMI 22.0 +/- 1.0 kg/m2), 51 inpatients with anorexia nervosa (AN, DSM IV criteria, mean BMI 14.3 +/- 1.5 kg/m2) and 27 patients with bulimia nervosa (BN, DSM IV criteria, mean BMI 21.7 +/- 5.8 kg/m2) by single strand conformation polymorphism analysis (SSCP). Several mutations were identified, including the frameshift mutation described (1). The mutations were as follows: a) The deletion of 4 bp (delta of CTCT at codon 211) results in a frameshift, thus rendering a truncated protein. This mutation has been assumed to be associated with dominantly-inherited morbid obesity in humans (1). Both the index patient (BMI 42.06 kg/m2, height 171 cm, age 19.6 years) and her mother (BMI 37.55 kg/m2, height 164 cm, age 42.5 years) were heterozygous for the deletion. b) A nonsense mutation at position 35 of the MC4-R was detected in two obese probands (BMI 31.29 kg/m2 and BMI 45.91 kg/m2). This mutation leads to a truncated protein that encompasses the N-terminal extracellular domain. Both carriers additionally showed (c) a missense mutation (Asp-37-Val). In both of these cases Tyr-35-Stop and Asp-37-Val were maternally transmitted, thus these variations form a haplotype. d) e) A male obese proband harbored two missense mutations (Ser-30-Phe, Gly-252-Ser). f)-i) Four different missense mutations (Pro-78-Leu, Thr-112-Met, Arg-165-Trp, Ile-317-Thr) were detected in four different male probands, respectively. All of these mutations (a to i) were found solely in extremely obese individuals whose BMIs were all above the 99th percentile. j) A silent mutation (C-579-T, Val-193-Val) was detected in a male underweight individual. k) A previously described polymorphism (Val-103-Ile; 3) was detected with similar frequencies in all different study groups. 1) We identified a novel polymorphism (Ile-251-Leu) with similar allele frequencies in all groups under study. In conclusion, our data indicate that mutations in the MC4-R are not uncommon. Whereas our data support the evidence for dominantly inherited obesity as revealed by the three obese probands with haplo-insufficiency, the functional significance of the missense mutations remains to be determined.
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300
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Mathiak K, Gowin W, Hebebrand J, Ziegler A, Blum WF, Felsenberg D, Lübbert H, Köpp W. Serum leptin levels, body fat deposition, and weight in females with anorexia or bulimia nervosa. Horm Metab Res 1999; 31:274-7. [PMID: 10333084 DOI: 10.1055/s-2007-978732] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
The objective of this retrospective study was to investigate the relation between serum leptin level and fat deposition in patients with eating disorders. 40 female inpatients with anorexia (n=24) or bulimia nervosa (n=16) were assessed for leptin level, body mass index (BMI), and percentage body fat by dual-energy X-ray absorbometry (DXA). The results show that percentage body fat is a better predictor for leptin level and clinical findings in eating disordered patients than BMI. We discuss the necessity for DXA measurements in anorectic patients for prognostic and research purposes.
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