Beat Steinmann - Academia.edu (original) (raw)

Papers by Beat Steinmann

Clinical Rheumatology, Feb 1, 1999

Pnas, 1986

We have characterized a mutation in a pro alpha 1(I) procollagen gene (COL1A1) that results in le... more We have characterized a mutation in a pro alpha 1(I) procollagen gene (COL1A1) that results in lethal (type II) osteogenesis imperfecta. The mutation is a single base change that results in a cysteine-for-glycine substitution at position 988 of the triple-helical portion of half of the alpha 1(I) chains of type I collagen. The mutation thus disrupts the (Gly-Xaa-Yaa)n pattern necessary for triple-helix formation, where Xaa and Yaa are other amino acids. These experiments establish the minimal mutation in a type I collagen gene capable of producing lethal disease, and the lethality demonstrates a selective mechanism for the stringent maintenance of the collagen gene structure.

European Journal of Pediatrics, May 1, 1991

Pediat Res, 1990

In Menkes' disease, a severe disturbance of copper handling appears to render copper unav... more In Menkes' disease, a severe disturbance of copper handling appears to render copper unavailable for copper-requiring processes. We have measured the activity of lysyl oxidase, the copper-dependent enzyme that initiates the cross-linking of collagen and elastin, in extracts of skin and aorta obtained at autopsy from a patient with unusually marked connective tissue manifestations, and found it to be only 6-12% of normal, thus suggesting a basis for these alterations.

Human Genetics, May 10, 2007

Clinical Chemistry and Laboratory Medicine, 2003

In this study, we present a versatile new procedure for the analysis of transferrin and its isofo... more In this study, we present a versatile new procedure for the analysis of transferrin and its isoforms isolated from human body fluids such as serum, plasma, and cerebrospinal fluid. This method is based on a three-step procedure: (i) isolation of transferrins using anion-exchange chromatography with UV detection; (ii) concentration of the transferrin fraction; (iii) detection of the transferrins with liquid chromatography-electrospray mass spectrometry. Pre-analytical sample procedures can be omitted and no immunoaffinity columns or transferrin-specific immunoassays were used. Anticoagulants such as heparin, EDTA, citrate, and oxalate do not interfere with our analysis. According to their respective molecular masses, up to ten different isoforms of transferrin could be identified in a serum sample from a patient with a congenital disorder of glycosylation type Ia (CDG-Ia). The method was successfully applied to different pathological samples from patients with CDG-Ia, CDG-Ib, CDG-Ic, CDG-Ie, CDG-If, and CDG-IIa. Additionally, samples from alcohol consumers that were found with turbidimetric immunoassay to contain increased levels of carbohydrate-deficient transferrin were analyzed.

Iranian Journal of Pediatrics, Sep 1, 2010

BackgroundThe Ehlers-Danlos syndrome type VI (EDSVI) is an autosomal recessive connective tissue ... more BackgroundThe Ehlers-Danlos syndrome type VI (EDSVI) is an autosomal recessive connective tissue disease which is characterized by severe hypotonia at birth, progressive kyphoscoliosis, skin hyperelasticity and fragility, joint hypermobility and (sub-)luxations, microcornea, rupture of arteries and the eye globe, and osteopenia. The enzyme collagen lysyl hydroxylase (LH1) is deficient in these patients due to mutations in the PLOD1 gene.Case PresentationWe report a 17-year-old boy, born to related parents, with severe kyphoscoliosis, scar formation, joint hypermobility and multiple dislocations, muscular weakness, rupture of an ocular globe, and a history of severe infantile hypotonia. EDS VI was suspected clinically and confirmed by an elevated ratio of urinary total lysyl pyridinoline to hydroxylysyl pyridinoline, abnormal electrophoretic mobility of the α-collagen chains, and mutation analysis.ConclusionBecause of the high rate of consanguineous marriages in Iran and, as a consequence thereof, an increased rate of autosomal recessive disorders, we urge physicians to consider EDS VI in the differential diagnosis of severe infantile hypotonia and muscular weakness, a disorder which can easily be confirmed by the analysis of urinary pyridinolines that is highly specific, sensitive, robust, fast, non-invasive, and inexpensive.

Nmr in Biomedicine, Jun 1, 2003

Human Genetics, May 1, 2009

... Xia Cao, Pei Yean Cheah Department of Colorectal Surgery, Singapore General Hospital, Outram ... more ... Xia Cao, Pei Yean Cheah Department of Colorectal Surgery, Singapore General Hospital, Outram Road, Singapore 169608, Singapore, e-mail: gcscao@sgh.com.sg, Tel.: +65-63213636, Fax: +65 ... Eva Brauers, Thomas Eggermann Institute of Human Genetics, Pauwelsstr. ...

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