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Bidwe A, Mayer F, Hawthorne C, Charitos A, Schuster A, Scheffknecht G. Use of ilmenite as an oxygen carrier in chemical looping combustion-batch and continuous dual fluidized bed investigation. ACTA ACUST UNITED AC 2011. [DOI: 10.1016/j.egypro.2011.01.072] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Hawthorne C, Dieter H, Bidwe A, Schuster A, Scheffknecht G, Unterberger S, Käß M. CO2 capture with CaO in a 200 kWth dual fluidized bed pilot plant. ACTA ACUST UNITED AC 2011. [DOI: 10.1016/j.egypro.2011.01.073] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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103
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Winder T, Schuster A, Becherer A, Gasser K, De Vries A, Gruber-Moesenbacher U, Muendlein A, Drexel H, Lang A. Advanced inoperable type B3 thymoma: monitoring of a novel therapeutic approach with radio-chemotherapy and sorafenib by FDG-PET and CT. Nuklearmedizin 2010; 49:N41-N43. [PMID: 20931150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2010] [Accepted: 05/21/2010] [Indexed: 05/30/2023]
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Keil T, Bockelbrink A, Reich A, Hoffmann U, Kamin W, Forster J, Schuster A, Willich SN, Wahn U, Lau S. The natural history of allergic rhinitis in childhood. Pediatr Allergy Immunol 2010; 21:962-9. [PMID: 20487364 DOI: 10.1111/j.1399-3038.2010.01046.x] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The distinction between 'seasonal' and 'perennial' allergic rhinitis (AR) is not always adequate. The 'Allergic Rhinitis and its Impact on Asthma' (ARIA) work group suggested a new classification for AR based on severity and duration of symptoms. Our primary aim was to describe the natural history and burden of AR according to the new ARIA criteria in a population-based birth cohort study of children up to 13 yr. We defined symptoms as 'severe' (impairment of daily activities) or 'mild' (no impairment) and 'persistent' (duration > 1 month) or 'intermittent' (<or=1 month) using annual questionnaires. Serum immunoglobulin E to five common aero-allergens was determined at six time points. We analyzed complete follow-up data from 467 children (54% boys). The 12-month prevalence of AR quadrupled from 6% (at age 3 yr) to 24% (at age 13 yr) in children with non-allergic parents and more than tripled from 13% (3 yr) to 44% (13 yr) in children with at least one allergic parent. Half or more of the children with AR had 'severe persistent' symptoms. At age 13, these children were significantly more often sensitized than those with 'mild persistent' disease: 91% vs. 70% (p = 0.015). Sensitization to aero-allergens (adjusted OR 18.9; 95%CI 9.3-38.4) and having 2 parents with allergy (3.1; 1.1-9.3) were significantly associated with AR. According to the ARIA criteria, the impact of AR seems to be substantial; the vast majority of affected children suffered persistently for periods of 2 months or more annually, and most of the children with persistent AR were impaired in their daily activities.
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Morton G, Schuster A, Perera D, Nagel E. Cardiac magnetic resonance imaging to guide complex revascularization in stable coronary artery disease. Eur Heart J 2010; 31:2209-15. [DOI: 10.1093/eurheartj/ehq256] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Davies E, Schuster A. Intercellular communication in plants: Evidence for a rapidly generated, bidirectionally transmitted wound signal. Proc Natl Acad Sci U S A 2010; 78:2422-6. [PMID: 16593006 PMCID: PMC319358 DOI: 10.1073/pnas.78.4.2422] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Wounding (whether by excision, abrasion, or puncture) elicited rapid, massive, and enduring formation of polysomes in aged pea stems and other mature tissues. The response depended on temperature and severity of wounding but not on water uptake, and it occurred in tissues adjacent to, distant from, above, and below the site of injury. The kinetics of polysome formation were similar in tissues adjacent to or up to 150 mm distant from the point of injury. The wound-induced increases in protein-synthesizing capacity of the polysomes both in vivo and in vitro were much greater than the increases in rRNA and poly(A)(+)RNA. The results indicate that wounding evokes the almost immediate production of a wound signal that travels rapidly both acropetally and basipetally to stimulate the recruitment of preexisting ribosomes onto primarily preexisting mRNA, thence forming polysomes with greatly enhanced protein-synthesizing capacity.
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Charitos A, Hawthorne C, Bidwe A, Korovesis L, Schuster A, Scheffknecht G. Hydrodynamic analysis of a 10kWth Calcium Looping Dual Fluidized Bed for post-combustion CO2 capture. POWDER TECHNOL 2010. [DOI: 10.1016/j.powtec.2010.02.012] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Kovacevic A, Schwahn B, Schuster A. Hyperlactic acidosis as metabolic side-effect of albuterol and theophylline in acute severe asthma. KLINISCHE PADIATRIE 2010; 222:271-2. [PMID: 20437331 DOI: 10.1055/s-0030-1248259] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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109
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Schuster A, Stelzer T, Petersen S, Ulrich J. Closed Crystalline Tubes as a Container System. Chem Eng Technol 2010. [DOI: 10.1002/ceat.200900618] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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110
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Winder T, Schuster A, Becherer A, Gasser K, De Vries A, Gruber-Moesenbacher U, Muendlein A, Drexel H, Lang A. Advanced inoperable type B3 thymoma: Monitoring of a novel therapeutic approach with radio-chemo therapy and sorafenib by FDG-PET and CT. Nuklearmedizin 2010. [DOI: 10.1055/s-0038-1626515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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111
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Schuster A, Wahn V. Intravenös verabreichte Immunglobuline bei Asthma bronchiale: eine therapeutische Alternative? Transfus Med Hemother 2009. [DOI: 10.1159/000222904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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112
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Hawthorne C, Trossmann M, Galindo Cifre P, Schuster A, Scheffknecht G. Simulation of the carbonate looping power cycle. ACTA ACUST UNITED AC 2009. [DOI: 10.1016/j.egypro.2009.01.182] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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113
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van den Berg TJ, (René) van Rijn L, Kaper-Bongers R, Vonhoff D, Völker-Dieben H, Grabner G, Nischler C, Emesz M, Wilhelm H, Gamer D, Schuster A, Franssen L, de Wit G, Coppens J. Disability Glare in the Aging Eye. Assessment and Impact on Driving ☆. JOURNAL OF OPTOMETRY 2009. [PMCID: PMC3972772 DOI: 10.3921/joptom.2009.112] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Purpose To compare different methods for the assessment of disability glare sensitivity in the elderly, to arrive at an objective assessment of the condition of the eye. To delineate the importance of straylight values in vision. Methods Three groups of subjects were studied: 1) Young subjects without any eye disease, 2) elderly subjects without any eye disease and 3) elderly subjects with (early) cataract in at least one eye. All subjects underwent 2 glare tests, 2 straylight tests, ETDRS visual acuity test, Pelli Robson contrast sensitivity test, refraction, LOCS III cataract classification. Straylight was quantified by means of the straylight parameter s. Results Repeatability, discriminative ability, and added value as compared to visual acuity were low for the glare tests and good for the straylight measurements. For young normal subjects, with log(s)=0.9, the standard glare situation with low beams gives a contrast reduction of 1.3, whereas for the healthy 77 year olds this increases to 2. With cataract hardly affecting visual acuity, log(s) can be as high as 1.8, resulting in a contrast reduction of 3.4. Conclusion Straylight measurement is of relevance for the assessment of the glare-related hindrance during driving, and can be used to objectify complaints and aid in the decision-making regarding cataract surgery.
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Kovacevic A, Schmidt K, Nicolai T, Wisbauer M, Schuster A. Two Further Cases Supporting Nonsurgical Management in Congenital Lobar Emphysema. KLINISCHE PADIATRIE 2008; 221:232-6. [DOI: 10.1055/s-0028-1086032] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Butscher A, Wyss T, Schuster A, Gasser B, Fankhauser C. INTRAOPERATIVE INVESTIGATIONS ON THE BEHAVIOUR OF A NOVEL PE INLAY DESIGN FOR TKA. J Biomech 2008. [DOI: 10.1016/s0021-9290(08)70239-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Länge R, Desch B, Schuster A, Schwärzler P. Endometriosis genitalis externa im Leistenband. Geburtshilfe Frauenheilkd 2008. [DOI: 10.1055/s-2008-1078326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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117
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Eisenwort B, Heinrich M, Schuster A, Willinger U, Berzlanovich A. Suizide im Alter. Rechtsmedizin (Berl) 2007. [DOI: 10.1007/s00194-007-0472-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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118
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Eisenwort B, Berzlanovich A, Heinrich M, Schuster A, Chocholous P, Lindorfer S, Eisenwort G, Willinger U, Sonneck G. Suizidologie: Abschiedsbriefe und ihre Themen. DER NERVENARZT 2007; 78:672, 674-8. [PMID: 17119887 DOI: 10.1007/s00115-006-2210-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
BACKGROUND The study of suicide notes has a long tradition. It is important to integrate this study into psychological autopsy and to make contact with the bereaved. For the first time, we present an Austrian-German study and its themes. MATERIAL AND METHODS A consecutive series of suicides, investigated at the Department for Forensic Medicine in Vienna from Mai 2002 until April 2005, was examined for the presence of suicide notes. Suicide notes and demographic variables were integrated in an Access databank. RESULTS A total of 29% of the those committing suicide left notes, however, the bereaved of only about a quarter allowed these to be studied. The major part was hand written, addressed to the general public or family, and shorter than 150 words. Frequent themes were specific instructions, emotions, themes regarding the environment such as the family, occupation and leisure time, and themes regarding stations of life and illness.
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Beer G, Manestar M, Schuster A, Lang A, Kompatscher P. The thoracoacromial vessels as recipient vessels in microsurgery: An anatomic and sonographic study. J Plast Reconstr Aesthet Surg 2007. [DOI: 10.1016/j.bjps.2007.01.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Davis J, Williams H, Bramlett K, Powell T, Schuster A, Richards P, Yu K, Gennevois D. (781). THE JOURNAL OF PAIN 2007. [DOI: 10.1016/j.jpain.2007.02.186] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Willumeit R, Schuster A, Iliev P, Linser S, Feyerabend F. Phospholipids as implant coatings. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2007; 18:367-80. [PMID: 17323171 DOI: 10.1007/s10856-006-0702-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2006] [Accepted: 10/27/2006] [Indexed: 05/14/2023]
Abstract
Bio-interfaces such as bio-membranes are of outmost importance for a variety of live processes. Among them are cell-interactions which take place in, on or through cell membranes. Therefore we propose to cover metallic surfaces with phospholipids to facilitate cell-material interaction. Four lipids, 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC), 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanolamine (POPE), 1-palmitoyl-2- oleoyl-sn-glycero-3-[phospho-L-serine] (POPS) and 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-rac-(1-glycerol) (POPG), were applied to four metallic growth substrates with different surface structure, roughness and porosity. The interaction of the osteosarcoma cell line MG-63 was investigated in terms of cell adhesion and viability (MTT (methylthiazolyldiphenyl-tetrazolium bromide) assay). While POPS in general had a negative influence, the most suitable combination in terms of viability per adherent MG-63 is the coating of porous Ti6Al4V material with the phospholipids POPE or POPC. The analysis of viability of mouse macrophages RAW 264.7 and their tumor necrosis factor alpha (TNF-alpha) release showed that the adhesion and viability is worst on POPS while the TNF-alpha release was highest. To elucidate the potential of phospholipids to prevent or support bacterial growth, the bacterial number of Gram positive and Gram negative bacteria was investigated. For lipid concentrations higher than 1 mM in solution a growth stimulating effect independent of the lipid type was detected. On a lipid coated surface the number of bacteria was reduced by 81%, 74% and 51% for POPC, POPG and POPE.
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Silberstein M, Tzemach A, Dovgolevsky N, Fishelson M, Schuster A, Geiger D. Online system for faster multipoint linkage analysis via parallel execution on thousands of personal computers. Am J Hum Genet 2006; 78:922-35. [PMID: 16685644 PMCID: PMC1474109 DOI: 10.1086/504158] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2005] [Accepted: 03/08/2006] [Indexed: 11/03/2022] Open
Abstract
Computation of LOD scores is a valuable tool for mapping disease-susceptibility genes in the study of Mendelian and complex diseases. However, computation of exact multipoint likelihoods of large inbred pedigrees with extensive missing data is often beyond the capabilities of a single computer. We present a distributed system called "SUPERLINK-ONLINE," for the computation of multipoint LOD scores of large inbred pedigrees. It achieves high performance via the efficient parallelization of the algorithms in SUPERLINK, a state-of-the-art serial program for these tasks, and through the use of the idle cycles of thousands of personal computers. The main algorithmic challenge has been to efficiently split a large task for distributed execution in a highly dynamic, nondedicated running environment. Notably, the system is available online, which allows computationally intensive analyses to be performed with no need for either the installation of software or the maintenance of a complicated distributed environment. As the system was being developed, it was extensively tested by collaborating medical centers worldwide on a variety of real data sets, some of which are presented in this article.
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Petersen S, Hellmich G, Schuster A, Lehmann D, Albert W, Ludwig K. Stapled transanal rectal resection under laparoscopic surveillance for rectocele and concomitant enterocele. Dis Colon Rectum 2006; 49:685-9. [PMID: 16583290 DOI: 10.1007/s10350-006-0512-7] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
PURPOSE Stapled transanal rectal resection recently became a recommended surgical procedure for obstructed defecation syndrome. One problem when using a transanal stapling device for rectal surgery is the potential threat to structures located in front of the anterior rectal wall. We decided to perform a combined procedure of transanal rectal resection with a simultaneous laparoscopy for patients with obstructed defecation syndrome and an enterocele. METHODS Between November 2002 and May 2005 a total of 41 patients were treated surgically for obstructed defecation syndrome. Four patients with concomitant enterocele underwent stapled transanal rectal resection under laparoscopic surveillance. Before surgery all patients underwent preoperative assessment, including clinical examination, colonoscopy, conventional video defecography, dynamic magnetic resonance imaging defecography, gynecology examinations, and psychologic evaluation. RESULTS The mean operative time was 50 (+/-16.5) minutes for the conventional stapled transanal rectal resection and 67 (+/-14.1) minutes for combined laparoscopy and stapled transanal rectal resection (P < 0.01). Three major complications were observed: two had bleeding in the staple line (one from each group) and one had a late abscess in the staple line. CONCLUSIONS The combination of the stapled transanal rectal resection procedure and laparoscopy provides the opportunity to perform transanal rectal resection without the threat of intra-abdominal lesions caused by enterocele.
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Lampe B, Thiel A, Poggenborg J, Schuster A, Vollmar S, Hesselmann A, Haupt WF. Development of a single pulse transcranial magnetic stimulation protocol for individual localization of brain regions for semantic processing. KLIN NEUROPHYSIOL 2006. [DOI: 10.1055/s-2006-939215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Ulrich G, Pompe K, Ballmann M, Schuster A, Ziebach R, Schulz W. 389 Social anxiety and inhibition in 10- to 14-year-old youngsters with Cystic Fibrosis: further evidence of resilience? J Cyst Fibros 2006. [DOI: 10.1016/s1569-1993(06)80329-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Ullrich G, Pompe K, Ballmann M, Schuster A, Ziebach R, Schulz W. 388 Stress perception, stress management, and perceived disease impact among 10- to 14-year-old CF youngsters. J Cyst Fibros 2006. [DOI: 10.1016/s1569-1993(06)80328-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Schuster A, Weisschuh N, Jägle H, Besch D, Janecke AR, Zierler H, Tippmann S, Zrenner E, Wissinger B. Novel rhodopsin mutations and genotype-phenotype correlation in patients with autosomal dominant retinitis pigmentosa. Br J Ophthalmol 2005; 89:1258-64. [PMID: 16170112 PMCID: PMC1772865 DOI: 10.1136/bjo.2004.063933] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
AIM To identify novel or rare rhodopsin gene mutations in patients with autosomal dominant retinitis pigmentosa and description of their clinical phenotype. METHODS The complete rhodopsin gene was screened for mutations by DNA sequencing in index patients. Mutation specific assays were used for segregation analysis and screening for controls. Eight patients from five families and their relatives were diagnosed with autosomal dominant retinitis pigmentosa (adRP) by means of clinical evaluation. RESULTS Mutation screening identified five different rhodopsin mutations including three novel mutations: Ser176Phe, Arg314fs16, and Val20Gly and two missense mutations, Pro215Leu and Thr289Pro, that were only reported once in a mutation report. Electrophysiological and psychophysical testings provide evidence of an impaired rod system with additionally affected cone system in subjects from each genotype group. Visual function tended to be less affected in subjects with the Arg314fs16 and Val20Gly mutations than in the Ser176Phe phenotype. In contrast, Pro215Leu and Thr289Pro mutations caused a remarkably severe phenotype. CONCLUSION The ophthalmic findings support a correlation between disease expression and structural alteration: (1) extracellular/intradiscal Val20Gly and cytoplasmic Arg314fs16 mutation-mild adRP phenotype; (2) Ser176Phe mutation-"mostly type 1" disease; (3) predicted alteration of transmembrane domains TM V and TM VII induced by Pro215Leu and Thr289Pro-severe phenotype. However, variation of phenotype expression in identical genotypes may still be a typical feature of RHO mutations.
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Nickel R, Illi S, Lau S, Sommerfeld C, Bergmann R, Kamin W, Forster J, Schuster A, Niggemann B, Wahn U. Variability of total serum immunoglobulin E levels from birth to the age of 10 years. A prospective evaluation in a large birth cohort (German Multicenter Allergy Study). Clin Exp Allergy 2005; 35:619-23. [PMID: 15898984 DOI: 10.1111/j.1365-2222.2005.02237.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
BACKGROUND Many environmental factors influence the concentration of total serum IgE (tIgE); however, tIgE synthesis is believed to be under strong genetic influence. Multiple genetic studies on tIgE regulation have been performed. For these population-based studies tIgE was commonly determined at one time-point, assuming that tIgE phenotypes (adjusted for age and gender) are stable over time. OBJECTIVE We assessed correlations of tIgE levels from birth to the age of 10 years in the birth cohort MAS (Multicenter Allergy Study; n=1314). MATERIALS AND METHODS We determined cord-blood IgE levels, total and specific IgE at the age of 1, 2, 3, 5, 6, 7, and 10 years. Spearman correlation coefficients were calculated for tIgE at different time-points. All analyses were performed in the entire cohort, adjusted for gender, as well as in non-atopic children only. RESULTS tIgE percentiles increased steadily from birth to the age of 10 years with higher values for boys than for girls at each time-point. tIgE values from birth to 3 years of age correlated poorly with tIgE levels at 10 years (r<0.5). However, good correlations (r>0.8) were observed for tIgE concentrations at 6, 7 and 10 years. The same results were observed when the analyses were limited to non-atopic children. CONCLUSION In childhood, tIgE levels underlie remarkable variation over time even in the absence of atopy. For cross-sectional population-based genetic and epidemiologic studies, tIgE values of children <5 years should be interpreted with caution since these values correlate poorly with tIgE levels later in life.
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Derichs N, Schuster A, Grund I, Ernsting A, Stolpe C, Körtge-Jung S, Gallati S, Stuhrmann M, Kozlowski P, Ballmann M. Homozygosity for L997F in a child with normal clinical and chloride secretory phenotype provides evidence that this Cystic Fibrosis Transmembrane Conductance Regulator mutation does not cause cystic fibrosis. Clin Genet 2005; 67:529-31. [PMID: 15857421 DOI: 10.1111/j.1399-0004.2005.00437.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Lange S, Diehm C, Darius H, Haberl R, Allenberg JR, Pittrow D, Schuster A, von Stritzky B, Tepohl G, Trampisch HJ. High Prevalence of Peripheral Arterial Disease and Low Treatment Rates in Elderly Primary Care Patients with Diabetes. Exp Clin Endocrinol Diabetes 2004; 112:566-73. [PMID: 15578331 DOI: 10.1055/s-2004-830408] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Representative data on peripheral arterial disease (PAD) in community-based office practice are scarce while at the same time of high interest. Thus, we aimed to determine the prevalence of peripheral arterial disease (PAD), comorbidity of atherothrombotic manifestations, and treatment intensity among elderly diabetic patients in primary care. In this monitored cross-sectional study, 344 general practitioners throughout Germany determined the ankle-brachial index (ABI) of 6880 consecutive, unselected patients aged 65 years or older with bilateral Doppler ultrasound measurements. PAD was defined according to the recent American Heart Association guidelines (using the higher of the 2 systolic ankle pressures: ABI < 0.9) or peripheral revascularisation, or amputation because of PAD. Coronary events (CAD) and cerebrovascular events (CVD) were taken from the patient's history without additional diagnostic measures. Diabetes was defined according to the clinical diagnosis of the physician and/or HbA1c > or = 6.5 % and/or intake of oral antidiabetic medication and/or application of insulin. 1.743 patients were classified as diabetics: the median disease duration was 6 years (1st; 3rd quartile: 2; 11), median HbA1c 6.6 % (5.9; 7.3), mean age 72.5 +/- 5.4 years, and 51.4 % were females. Diabetics had in comparison with non-diabetics a higher prevalence of PAD defined as ABI < 0.9 (26.3 % vs. 15.3 %, univariate odds ratio 2.0 [95 % confidence interval: 1.7; 2.3]), intermittent claudication (5.1 % vs. 2.1 %, OR: 2.5 [1.9; 3.4]), known CAD (16.1 % vs. 10.6 %, OR: 1.6 [1.4; 1.9]), and known CVD (6.8 % vs. 4.8 %; OR: 1.4 [1.2; 1.8]). 57.4 % of the diabetics with previously known PAD (as only atherothrombotic manifestation) received antiplatelet therapy (vs. 75.1 % with CAD and/or CVD only). The ABI was suitable as screening measure in the primary care setting. In elderly diabetics in comparison to non-diabetics, the prevalence of PAD was very high. Despite the known benefits of antiplatelet therapy, PAD patients were less intensively treated than patients with CAD or CVD.
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Hergan K, Schuster A, Mair M, Burger R, Töpker M. Normalwerte der Herzdurchmesser in der Cine-MRT. ROFO-FORTSCHR RONTG 2004; 176:1599-606. [PMID: 15497078 DOI: 10.1055/s-2004-813627] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
PURPOSE To measure the normal diameters of cardiac cavities in standard cardiac views using cine MRI. MATERIALS AND METHODS Fifty-six volunteers were examined (27 male, 29 female) on a 1.5 T MR unit with ECG-triggered single shot free precision (SSFP) cine MR sequences and parallel image acquisition. Standardized echocardiographic planes were used to depict the heart of all volunteers (short axis, 4-chamber view, left and right 2-chamber views). The different diameters of the cardiac cavities were measured using a fixed protocol. RESULTS For the estimation of ventricular dilatation, the important female/male cross diameters of the left ventricle are 45.2 +/- 3.4/51.6 +/- 4.6 mm diastolic and 30.5 +/- 3.5/33.8 +/- 3.6 mm systolic, and of the right ventricle 30.7 +/- 3.8/37.1 +/- 5.9 mm diastolic and 22.3 +/- 3.8/28.1 +/- 4.4 mm systolic. For the determination of a left ventricular hypertrophy, relevant septal wall thickness measured in the short axis of the left ventricle of female/male volunteers are 8.0 +/- 1.0/9.9 +/- 1.2 mm diastolic and 10.9 +/- 1.4/13.6 +/- 1.9 mm systolic. The measured normal values of male volunteers were generally higher than those of female volunteers. The thickness of the ventricular septum correlated well when measured in the short axis and 4-chamber view. When measured in the 4-chamber view, the longitudinal diameter of the ventricles had a higher value in diastole and a lower value in systole, compared to the 2-chamber views of the right and left cardiac cavities. The atrial longitudinal diameters were higher in the 4-chamber view compared to the 2-chamber views, without any difference in systole or diastole. CONCLUSION Diameters of cardiac cavities are easily and quickly measured. Using the tables with the normal values published here, it is simple to estimate an abnormal size of the heart.
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Schuster A, Voggenreiter HF, Dunand DC, Eggeler G. A new type of intrinsic two-way shape-memory effect in hooks of NiTi-wires. ACTA ACUST UNITED AC 2003. [DOI: 10.1051/jp4:20031092] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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Habedank B, Thiel A, Klein JC, Schuster A, Haupt WF, Heiss WD. Individuelle, funktionelle Lokalisierung des Broca-Areales als Zielpunkt für die repetitive TMS mittels PET. KLIN NEUROPHYSIOL 2003. [DOI: 10.1055/s-2003-816445] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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137
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Darius H, Pittrow D, Haberl R, Trampisch HJ, Schuster A, Lange S, Tepohl HG, Allenberg JR, Diehm C. Are elevated homocysteine plasma levels related to peripheral arterial disease? Results from a cross-sectional study of 6880 primary care patients. Eur J Clin Invest 2003; 33:751-7. [PMID: 12925033 DOI: 10.1046/j.1365-2362.2003.01196.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND It is still unclear whether the strength of the association between elevated plasma homocysteine (HC) levels and peripheral arterial disease (PAD), coronary artery disease (CAD) and cerebrovascular disease (CVD) is similar. METHODS Fasting homocysteine plasma levels were measured in 6880 unselected primary care patients aged 65 years or older. Presence of PAD was determined with the ankle brachial index, and both CAD and CVD were recorded according to patient history. RESULTS Median homocysteine levels in the total sample (58.0% females, mean age 72.5 years, mean body mass index 27.3 kg m-2) differed between patients with and without PAD: 15.2 micro mol L-1 (95% confidence interval [CI] 14.8; 15.7, vs. 13.9 micro mol L-1 (CI: 13.8; 14.1; P < 0.001). Peripheral arterial disease prevalence moderately increased from 13.0% in the lowest HC quintile to 24.3% in the highest quintile (crude odds ratio [OR], 2.1 [CI: 1.7; 2.6]). The frequency of atherothrombotic manifestations in the patients' history increased nearly linearly across the homocysteine quintiles in the univariate analysis. However, the association diminished substantially after adjusting for known interfering variables: the ORs between the HC highest fifth vs. lowest fifth (adjusted for age, gender, smoking status, diabetes, hypertension lipid disorders, and estimated glomerular filtration rate levels) for PAD decreased to 1.4, for CAD to 1.0 (NS), and for CVD to 1.1. (NS). CONCLUSIONS Elevated HC is only slightly more related to PAD than to CAD and CVD. After adjustment for known risk factors, the effect size is small, and an association can no longer be observed between homocysteine and CAD and CVD.
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Schuster A, Burzawa S, Jemal M, Loizillon E, Couerbe P, Whigan D. Quantitative determination of the HIV protease inhibitor atazanavir (BMS-232632) in human plasma by liquid chromatography-tandem mass spectrometry following automated solid-phase extraction. J Chromatogr B Analyt Technol Biomed Life Sci 2003; 788:377-86. [PMID: 12705978 DOI: 10.1016/s1570-0232(03)00063-1] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
A selective, accurate, and reproducible LC-MS-MS assay was developed for the determination of the HIV protease inhibitor atazanavir (BMS-232632) in human plasma samples. The method involved automated solid-phase extraction of atazanavir and a stable isotope analog internal standard (I.S.) using Oasis HLB 10 mg 96-well SPE plates. A portion of the reconstituted sample residue was injected onto a C(18) HDO analytical column which was configured with a triple quad mass spectrometer for analyte determination by positive ion electrospray. The assay was linear from 1.00 to 1,000 ng/ml with a lower limit of quantitation of 1.00 ng/ml. The inter- and intra-day coefficients of variation (C.V.) for the assay were <4%, and the accuracy was 99-102%. Atazanavir was stable in human plasma for at least 109 h at room temperature and for at least 1 year at -20 degrees C.
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Pinggera GM, Schuster A, Pallwein L, Frauscher F, Hohlbrugger G, Bartsch G, Strasser H. Alpha-blockers increase vesical and prostatic blood flow and bladder capacity. ACTA ACUST UNITED AC 2003. [DOI: 10.1016/s1569-9056(03)80630-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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140
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Schuster A, Daschner F. [Antibacterial products in the home: chance or hazard?]. Dtsch Med Wochenschr 2002; 127:2340-4. [PMID: 12410441 DOI: 10.1055/s-2002-35198] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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141
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Hansen G, Hoffjan S, Mosler K, Schuster A. Effect of recombinant human DNase on alpha1-proteinase inhibitor function: an experimental approach to the combined clinical use of rhDNase and alpha1-PI in CF patients. Lung 2002; 179:185-94. [PMID: 11891608 DOI: 10.1007/s004080000060] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/13/2001] [Indexed: 11/30/2022]
Abstract
Chronic inflammation in cystic fibrosis (CF) airways leads to high concentrations of deoxyribonucleic acid (DNA) and neutrophil elastase (NE). Both play a major role in CF lung pathophysiology and are aims of new therapeutic approaches: rhDNase degrades highly viscosic DNA and alpha1-proteinase inhibitor (alpha1-PI) inhibits NE activity and thereby pulmonary inflammation and hypersecretion. Given the reports on increased sputum NE concentrations upon rhDNase inhalation, there is a rationale for a combined rhDNase/alpha1-PI treatment. With the question of whether a combined therapy is feasible, we first investigated in vitro whether incubation of CF sputum with rhDNase changes proteolytic and secretagogue activity of sputum supernatants and its inhibition by alpha1-PI. Next, we studied whether incubation of alpha1-PI with rhDNase impairs the inhibitory effect of alpha1-PI on proteolytic activity of NE and the inhibitory effect of alpha1-PI on NE-induced secretion from a human mucoepidermoid cell line. Incubation of CF sputum with rhDNase led to a twofold increase in sputum NE activity. Correspondingly, the inhibitory effect of alpha1-PI on sputum NE activity and on secretion induced by these sputum samples was significantly reduced by rhDNase. Preincubation of alpha1-PI with rhDNase significantly reduced the inhibitory effect of alpha1-PI on purified NE activity and on NE-induced secretion. However, this effect was limited to alpha1-PI concentrations lower than those achievable after inhalation. Therefore, impairment of alpha1-PI function by rhDNase is not likely to be relevant in vivo, provided that a sufficient dosage of alpha1-PI is inhaled.
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Gottschling D, Boer J, Schuster A, Holzmann B, Kessler H. Cellular solid-phase binding assay and mass spectrometry for screening of alpha 4 beta 7 integrin antagonists. Bioorg Med Chem Lett 2001; 11:2997-3000. [PMID: 11714596 DOI: 10.1016/s0960-894x(01)00611-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A qualitative cellular solid-phase binding assay for screening alpha 4 beta 7 integrin antagonists attached via photolinker to TentaGel Macrobeads has been developed. An activation of the integrins with Mn(2+) was necessary to achieve binding to the bead bound antagonists. The identification of the resin bound compounds was done by mass spectrometry.
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Oishi H, Budel S, Schuster A, Stergiopulos N, Meister JJ, Bény JL. Cytosolic-free calcium in smooth-muscle and endothelial cells in an intact arterial wall from rat mesenteric artery in vitro. Cell Calcium 2001; 30:261-7. [PMID: 11587550 DOI: 10.1054/ceca.2001.0233] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The regulation of cytosolic-free calcium concentration of smooth-muscle and endothelial cells was mainly studied on cultured cells where the cross talk between these two coupled cell types is lost. In the present study, the cytosolic-free calcium concentration in the endothelial and the smooth-muscle cells was examined in an intact arterial wall in vitro. Strips of the main branch of rat mesenteric artery were used. Cytosolic-free calcium concentration [Ca2+]i was estimated by determining the fluorescence ratio of the two calcium probes, Fluo-4 and Fura red. The emitted fluorescence of both probes was measured with a confocal microscope. We showed that potassium and phenylephrine, which increase the cytosolic -free calcium concentration of the smooth-muscle cells, also indirectly influence the calcium concentration in the endothelial cells. By simultaneously determining [Ca2+]i in the endothelial and the smooth-muscle cells of an arterial strip, we observed that when calcium increases in the endothelial cells in response to acetylcholine, it slightly decreases in the smooth-muscle cells. We conclude that the regulation of [Ca2+]i in the arterial endothelial cell, depends according to the stimuli either upon the endothelial cells themselves, or upon the coupled smooth-muscle cells.
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Budel S, Schuster A, Stergiopoulos N, Meister JJ, Bény JL. Role of smooth muscle cells on endothelial cell cytosolic free calcium in porcine coronary arteries. Am J Physiol Heart Circ Physiol 2001; 281:H1156-62. [PMID: 11514282 DOI: 10.1152/ajpheart.2001.281.3.h1156] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We tested the hypothesis that the cytosolic free calcium concentration in endothelial cells is under the influence of the smooth muscle cells in the coronary circulation. In the left descending branch of porcine coronary arteries, cytosolic free calcium concentration ([Ca(2+)](i)) was estimated by determining the fluorescence ratio of two calcium probes, fluo 4 and fura red, in smooth muscle and endothelial cells using confocal microscopy. Acetylcholine and potassium, which act directly on smooth muscle cells to increase [Ca(2+)](i), were found to indirectly elevate [Ca(2+)](i) in endothelial cells; in primary cultures of endothelial cells, neither stimulus affected [Ca(2+)](i), yet substance P increased the fluorescence ratio twofold. In response to acetylcholine and potassium, isometric tension developed by arterial strips with intact endothelium was attenuated by up to 22% (P < 0.05) compared with strips without endothelium. These findings suggest that stimuli that increase smooth muscle [Ca(2+)](i) can indirectly influence endothelial cell function in porcine coronary arteries. Such a pathway for negative feedback can moderate vasoconstriction and diminish the potential for vasospasm in the coronary circulation.
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MESH Headings
- Acetylcholine/pharmacology
- Adrenergic beta-Agonists/pharmacology
- Animals
- Bradykinin/pharmacology
- Calcium/metabolism
- Cells, Cultured
- Coronary Vessels/cytology
- Coronary Vessels/drug effects
- Coronary Vessels/metabolism
- Cytosol/metabolism
- Dose-Response Relationship, Drug
- Endothelium, Vascular/cytology
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/metabolism
- Fluorescent Dyes
- In Vitro Techniques
- Isometric Contraction/drug effects
- Isometric Contraction/physiology
- Microscopy, Confocal
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Potassium/pharmacology
- Substance P/pharmacology
- Swine
- Vasodilation/drug effects
- Vasodilation/physiology
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Boer J, Gottschling D, Schuster A, Semmrich M, Holzmann B, Kessler H. Design and synthesis of potent and selective alpha(4)beta(7) integrin antagonists. J Med Chem 2001; 44:2586-92. [PMID: 11472212 DOI: 10.1021/jm0005508] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Interactions of the integrins alpha(4)beta(7) with its cognate ligand mucosal addressin cell adhesion molecule-1 (MAdCAM-1) play a crucial role in the development of mucosa-associated lymphoid organs, in the generation of mucosal immune responses, and in diverse pathological processes such as chronic inflammatory bowel disease and type I diabetes. Using a previously developed spatial screening technique we describe the development of potent and selective alpha(4)beta(7) integrin antagonists based on the domain 1 Leu-Asp-Thr (LDT) sequence of MAdCAM-1 that is essential for alpha(4)beta(7) integrin binding. A library of homodetic cyclic penta- and hexapeptides was synthesized presenting the pharmacophoric LDT-sequence in different conformations. The cyclic hexapeptide P10 cyclo(Leu-Asp-Thr-Ala-D-Pro-Ala) inhibits alpha(4)beta(7) integrin mediated cell adhesion to MAdCAM-1 effectively. Further optimization of the lead structure P10 resulted in cyclic hexapeptides with enhanced activity. The compounds P25 cyclo(Leu-Asp-Thr-Ala-D-Pro-Phe), P28 cyclo(Leu-Asp-Thr-Asp-D-Pro-Phe), P29 cyclo(Leu-Asp-Thr-Asp-D-Pro-His), and P30 cyclo(Leu-Asp-Thr-Asp-D-Pro-Tyr) strongly inhibited alpha(4)beta(7) integrin mediated cell adhesion to MAdCAM-1, but they did not affect binding of the closely related alpha(4)beta(1) integrin to VCAM-1.
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Beer S, Simins AB, Schuster A, Holzmann B. Molecular cloning and characterization of a novel SH3 protein (SLY) preferentially expressed in lymphoid cells. BIOCHIMICA ET BIOPHYSICA ACTA 2001; 1520:89-93. [PMID: 11470164 DOI: 10.1016/s0167-4781(01)00242-1] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
A novel full-length cDNA was isolated from a murine T-cell lymphoma library that has an open reading frame encoding 381 amino acids. The predicted protein (termed SLY) contains a Src homology 3 domain and a sterile alpha motif, suggesting that it functions as a signaling adaptor protein in lymphocytes. Northern blot and in situ hybridization analysis showed a preferential expression in lymphoid tissues. The sly gene is located on the X-chromosome in close proximity to genes involved in various immune disorders. This is consistent with an additional role of SLY in immune pathology.
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Söderpalm AH, Schuster A, de Wit H. Antiemetic efficacy of smoked marijuana: subjective and behavioral effects on nausea induced by syrup of ipecac. Pharmacol Biochem Behav 2001; 69:343-50. [PMID: 11509190 DOI: 10.1016/s0091-3057(01)00533-0] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Although the public debate about the legalization of marijuana has continued for as long as 25 years, few controlled studies have been conducted to assess its potential medical benefits. The present study examined the antiemetic effect of smoked marijuana cigarettes (8.4 and 16.9 mg Delta(9)-tetrahydrocannabinol [THC]) compared to a highly potent antiemetic drug, ondansetron (8 mg) in 13 healthy volunteers. Nausea and emesis were induced by syrup of ipecac. Marijuana significantly reduced ratings of "queasiness" and slightly reduced the incidence of vomiting compared to placebo. Ondansetron completely eliminated the emetic effects of ipecac. These findings support and extend previous results, indicating that smoked marijuana reduces feelings of nausea and also reduces emesis in this model. However, its effects are very modest relative to ondansetron, and the psychoactive effects of marijuana are likely to limit its clinical usefulness in the general population.
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Filser JG, Faller TH, Bhowmik S, Schuster A, Kessler W, Pütz C, Csanády GA. First-pass metabolism of 1,3-butadiene in once-through perfused livers of rats and mice. Chem Biol Interact 2001; 135-136:249-65. [PMID: 11397395 DOI: 10.1016/s0009-2797(01)00194-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
First-pass metabolism of 1,3-butadiene (BD) leading to 1,2-epoxy-3-butene (EB), 1,2:3,4-diepoxybutane (DEB), 3-butene-1,2-diol (B-diol), 3,4-epoxy-1,2-butanediol (EBD) and crotonaldehyde (CA) was studied quantitatively in the once-through BD perfused liver of mouse and rat by means of an all-glass gas-tight perfusion system. Metabolites were analyzed using gas chromatography equipped with mass selective detection. The perfusate consisted of Krebs-Henseleit buffer (pH 7.4) containing bovine erythrocytes (40%v/v) and BD. The perfusion flow rates through the livers were 3-4 ml/min (mouse) and 17-20 ml/min (rat). The BD concentrations in the liver perfusates were 330 nmol/ml (mouse) and 240 nmol/ml (rat) being high enough to reach almost saturation of BD metabolism. The mean rates of BD transformation were about 0.014 and 0.055 mmol/h per liver of a mouse and a rat, respectively, being similar to the values expected from in-vivo measurements. There were marked species differences in the formation of BD metabolites. In the effluent of mouse livers, all three epoxides (EB: 9.4 nmol/ml; DEB: 0.06 nmol/ml; EBD: 0.07 nmol/ml) and B-diol (8.2 nmol/ml) were detected. In the perfusate leaving naïve rat livers, only EB and B-diol were found. In that of rat liver, EB concentration was 8.5 times smaller than in that of mouse liver, whereas B-diol concentrations were similar in the effluent liver perfusate of both species. CA was below the limit of its detection (60 nmol/l) in the liver perfusate of mice and of naïve rats. Of BD metabolized, the sum of the metabolites investigated in the effluent amounted to only 30% (mouse) and 20% (rat). In first experiments with rat liver, glutathione (GSH) was depleted by pretreating the animals with diethylmaleate. With the exception of EBD (not quantifiable due to an interfering peak), all other metabolites including CA were found in the effluent perfusate summing up to about 70 and 100% of BD metabolized, which indicates the quantitative importance of the GSH dependent metabolism. In summary, the results demonstrate the relevance of an intrahepatic first-pass metabolism for metabolic intermediates of BD, which undergo further transformation immediately after their production in the liver before leaving this organ. Hitherto, the occurrence of this first-pass metabolism was only hypothesized. The findings will help to explain the drastic species difference between mice and rats in the carcinogenic potency of BD.
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Schuster A, Götte C, Bernhardt G, Buschauer A. Chiral separation of pheniramine-like 3-phenyl-3-heteroarylpropylamines by CE and HPLC methods. Chirality 2001; 13:285-93. [PMID: 11370017 DOI: 10.1002/chir.1033] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Analytical CE and HPLC methods were developed for the chiral separation of halogen-substituted 3-phenyl-3-(2-pyridyl)propylamines 1-4 (1: 3-(4-fluorophenyl) approximately, 2: 3-(3,4-difluorophenyl) approximately, 3: 3-(4-chlorophenyl) approximately, 4: 3-(3,4-dichlorophenyl) approximately ), 3-(4-fluorophenyl)-3-(2-thiazolyl)propylamine (5), and 3-(4-fluorophenyl)-3-(1-benzylimidazol-2-yl)propylamine (6), which are building blocks for the preparation of very potent arpromidine-type histamine H(2) receptor agonists. All amines were enantioseparated by CE with resolutions of at least 1.8 using alpha-, beta-, or gamma-cyclodextrin (CD) as chiral selectors. With heparin as buffer additive for CE the optical antipodes of 1-4 and 6 were separated with resolutions > or = 1.8. On RP-18 columns the separation of the (+)-(S)-acetylmandelic acid amides of racemic 2 (R = 0.9, alpha = 1.07) and the thioureas prepared by addition of 6 to 2,3,4,6-tetra-O-acetyl-beta-D-glucopyranosyl isothiocyanate (R = 2.0, alpha = 1.20) was successful, whereas the diastereomeric ureas prepared from 3 and (+)-(S)-1-(1-naphthyl)ethyl isocyanate could not be resolved. Separation of the diastereomeric isoindoles prepared from 1-5, o-phthaldialdehyde and 2,3,4,6-tetra-O-acetyl-1-thio-beta-D-glucopyranoside was achieved on a RP-18 phase (R > or = 0.4, a > or = 1.02). Direct separation of the enantiomers of 3 and 4 was achieved on a Cyclobond I column (R > or = 0.9, alpha > or = 1.07). alpha- and beta-CD were also useful as mobile phase additives for HPLC (3 and 4: RP-18 column, beta-CD, R > or = 0.4, alpha > or = 1.03; 3: RP-18 column, alpha-CD: R = 0.5, alpha = 1.04).
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Simons FE, Villa JR, Lee BW, Teper AM, Lyttle B, Aristizabal G, Laessig W, Schuster A, Perez-Frias J, Sekerel BE, Menten J, Leff JA. Montelukast added to budesonide in children with persistent asthma: a randomized, double-blind, crossover study. J Pediatr 2001; 138:694-8. [PMID: 11343045 DOI: 10.1067/mpd.2001.112899] [Citation(s) in RCA: 114] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVE We tested the hypothesis that adding montelukast to budesonide would improve asthma control in children with inhaled glucocorticoid-dependent persistent asthma. STUDY DESIGN In a multicenter, randomized, double-blind, crossover study, we compared the benefit of adding montelukast, 5 mg, or placebo once daily to budesonide, 200 microg, twice daily. RESULTS After a 1-month run-in with budesonide, 200 microg, twice daily, 279 children were randomized to montelukast or placebo. The mean +/- SD age was 10.4 +/- 2.2 years, the mean forced expiratory volume in 1 second (FEV(1)) was 77.7% +/- 10.6% predicted, and reversibility was 18.1% +/- 12.9%. Compared with adding placebo to budesonide, adding montelukast produced significant improvements in mean percent change from baseline FEV(1) (P =.062 [P =.010 for per-protocol analysis]), mean absolute change from baseline FEV(1) (P =.040), mean increase from baseline in morning (P =.023) and evening (P =.012) peak expiratory flows, decrease in exacerbation days by approximately 23% (P <.001), decreased beta2-agonist use (P =.013), and reduced blood eosinophil counts (P <.001). The treatments did not differ significantly with regard to safety. CONCLUSIONS Montelukast, 5 mg, added to budesonide improved asthma control significantly, indicated by a small additive effect on lung function and a clinically relevant decrease in asthma exacerbation days.
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