Using a human alpha B-crystallin genomic probe and human-mouse somatic cell hybrids, the human alpha B-gene was assigned to chromosome 11 and further corroborated by in situ hybridization to normal metaphase chromosomes. This assignment confirmed and regionally mapped the locus to q22.3-23.
View Article and Find Full Text PDFType I collagen mutations in a group of patients with lethal perinatal osteogenesis imperfecta were identified in fibroblast RNA by a new method which can detect, by chemical modification and cleavage, single mismatched bases in heteroduplexes formed between mRNA and normal cDNA probes. Control cDNA probes spanning the area of the pro-alpha 1(I) and pro-alpha 2(I) chains likely to contain the mutations were radioactively labeled and used to form heteroduplexes with total patient RNA. Treatment of these heteroduplexes with hydroxylamine followed by cleavage of the cDNA strand at reactive bases by piperidine identified mismatches in the pro-alpha 1(I) cDNA in four patients.
View Article and Find Full Text PDFHigh carbohydrate diets are known to increase the concentration of very low density lipoprotein (VLDL) and to lower the concentrations of low density lipoprotein (LDL) and high density lipoprotein (HDL) in plasma. Such diets also alter lipoprotein compositions and metabolism. The aims of the present study were to assess in detail the effects of a virtually fat-free high carbohydrate (CHO) diet (CHO greater than 85% and fat less than 1% of calories) on various aspects of LDL.
View Article and Find Full Text PDFThe Rutherford Appleton Laboratory clinical positron camera consists of two opposed multiwire proportional chambers (MWPCS) mounted on a rotating gantry capable of performing routine nuclear medicine studies. The system has operated since the end of 1986 with complete reliability. It has a sensitivity of 37 kcps MBq-1 cm3 per axial cm for a 20 cm diameter uniformly filled cylinder of activity.
View Article and Find Full Text PDFA codon frameshift mutation caused by a single base (U) insertion after base pair 4088 of prepro alpha 1(I) mRNA of type I procollagen was identified in a baby with lethal perinatal osteogenesis imperfecta. The mutation was identified in fibroblast RNA by a new method that allows the direct detection of mismatched bases by chemical modification and cleavage in heteroduplexes formed between mRNA and control cDNA probes. The region of mismatches was specifically amplified by the polymerase chain reaction and sequenced.
View Article and Find Full Text PDFThe effect of glycine-to-arginine mutations in the alpha 1 (I)-chain on collagen triple-helix structure in lethal perinatal osteogenesis imperfecta was studied by determination of the helix denaturation temperature and by computerized molecular modelling. Arginine substitutions at glycine residues 391 and 667 resulted in similar small decreases in helix stability. Molecular modelling suggested that the glycine-to-arginine-391 mutant resulted in only a relatively small localized disruption to the helix structure.
View Article and Find Full Text PDFAn unusual splicing mutation has been characterized in the pro alpha 1(I) collagen gene of a sporadic case of Ehlers-Danlos Syndrome Type VII. Cloning of primer extended cDNA in conjunction with R-looping experiments established that nearly half of the pro alpha 1(I) collagen gene transcripts are abnormally spliced, for they lack exon 6 sequences. Analysis of cloned genomic fragments revealed that one of the proband's alleles displays the substitution of an A for a G in the last nucleotide of exon 6.
View Article and Find Full Text PDFPrevious study has shown that the usual DNA marker for Norrie disease, the L1.28 probe which identifies the DXS7 locus, can recombine with the disease locus. In this study, we used a human ornithine aminotransferase (OAT) cDNA which detects OAT-related DNA sequences mapped to the same region on the X chromosome as that of the L1.
View Article and Find Full Text PDFTwo hundred and twenty-two patients with advanced breast cancer were randomised in two separate trials of similar design to either concomitant combination treatment or sequential use of the same drugs given as single agents changed only at disease progression. Both trials used cyclophosphamide, methotrexate, 5-fluorouracil and prednisone; the WCSG using triiodothyronine and the SECSG using vincristine as the remaining agent. A common data base was generated for these trials and combined for analysis.
View Article and Find Full Text PDFSite-directed mutagenesis of collagen genes offers a powerful new approach for studying structure-function relationships. The construction of engineered mutant collagen genes coding for glycine substitutions and their expression giving rise to the osteogenesis imperfecta type II phenotype in cells and transgenic mice has recently been achieved. This paper further defines the molecular abnormalities of collagen and bone pathology resulting from the expression of the mutant genes.
View Article and Find Full Text PDFSubstitution of a glycine residue in the triple helix of the alpha 1(I) chain by either arginine, valine or alanine was associated with the type II lethal perinatal osteogenesis imperfecta phenotype. This phenotype was also produced by a frameshift mutation that resulted in an abnormal amino acid sequence of the carboxy-terminal propeptide of the pro-alpha 1(I) chain. The latter baby, however, showed some clinical and radiographic differences from the other babies with type II OI.
View Article and Find Full Text PDFThis paper demonstrates the utility of C-reactive protein (CRP) in the diagnosis of infection in patients with acute renal failure. C-reactive protein can be assayed using plasma as effectively as using serum, thus avoiding the problems of microclots in serum, which can occur in samples from a heparinised patient. Plasma concentrations of C-reactive protein are unaffected by the process of haemodialysis.
View Article and Find Full Text PDFThe multiwire camera (MWC) produces high speed, quantitative autoradiography of radiolabelled substances in two-dimensional systems. While greatly superior to film-based systems in respect of speed and quantitativity the MWC has significantly poorer spatial resolution (particularly for high energy beta-emitting radiolabels) and the performance is ultimately limited by the noise induced in the images by Poisson statistics and counter background. Processing the MWC images with a maximum entropy algorithm significantly improves the performance of the system in these respects.
View Article and Find Full Text PDFStructurally abnormal type I collagen was identified in tissues and cultured fibroblasts from a case of lethal perinatal osteogenesis imperfecta. Two-dimensional gel electrophoresis of the CNBr peptides demonstrated that the alpha 1(I)CB7 peptide from the alpha 1(I) chain of type I collagen existed in a normal form and a mutant form with a more basic charge distribution (Bateman, J. F.
View Article and Find Full Text PDFWe have identified a family affected with X-linked recessive Norrie disease, in which a recombinational event occurred between the disease locus and the DXS7 locus identified by the probe L1.28. The addition of our family brings the total of published informative families to seven, with a maximum lod score of 7.
View Article and Find Full Text PDFSyrian hamster embryo fibroblasts transformed by 4-nitroquinoline-1-oxide (NQT-SHE cells) failed to synthesize the pro-alpha 1(I) subunit of type I procollagen but continued to synthesize altered forms of the other subunit, pro-alpha 2(I) (Peterkofsky, B., and Prather, W. (1986) J.
View Article and Find Full Text PDFSerum IgG antibodies to native and denatured human type II collagen (Col II) were measured using an enzyme linked immunosorbent assay (ELISA). One hundred and thirty one patients with various forms of arthritis such as rheumatoid arthritis (RA), ankylosing spondylitis (AS), psoriatic arthritis (PSA). Reiter's Syndrome (RS), osteoarthritis (OA), and gout, 60 with autoimmune connective tissue disease, and 37 with the chronic inflammatory conditions--graft versus host disease and leprosy--were studied.
View Article and Find Full Text PDFThe authors studied a four-generation family with autosomal dominant congenital cataracts (ADCCs) using linkage analysis with 23 polymorphic phenotypic markers and DNA restriction fragment length polymorphisms (RFLPs) detected by lens-specific DNA probes. A total of 19 family members were studied and the ten affected members had embryonal lens opacities. Close linkage was rejected with DNA probes encoding beta-crystallin, gamma-crystallin, and the major intrinsic protein of the lens fiber membrane (MIP) excluding defects of these genes as the cause of the cataract in this family.
View Article and Find Full Text PDFIt is difficult to study the regulation and interactions of the connective tissue macromolecules in vivo. However, studies of genetically determined diseases of the connective tissues have yielded a large amount of new information in these areas. Specific molecular defects can then be correlated with the functional and pathological changes in the tissues.
View Article and Find Full Text PDFSubstitutions of single glycine residues of alpha 1(I) collagen have previously been associated with the inherited disease osteogenesis imperfecta type II. Transgenic mice bearing a mutant alpha 1(I) collagen gene into which specific glycine substitutions have been engineered show a dominant lethal phenotype characteristic of the human disease, and demonstrate that as little as 10% mutant gene expression can disrupt normal collagen function.
View Article and Find Full Text PDFThe authors recorded electroretinograms for 27 autistic patients and 20 age- and sex-matched healthy volunteers. Thirteen (48%) of the autistic patients demonstrated subnormal b-wave amplitudes, which may indicate abnormal retinal function. One patient was tested serially at two sites; his low b-wave amplitude did not vary over time or between the two sites.
View Article and Find Full Text PDFA clonal cell strain, UMR 201, was established from a culture of rat calvarial cells by the process of limiting dilution on a collagen substratum. One-day-old neonatal rat calvaria stripped of periosteum were placed on collagen in alpha-MEM with 10% fetal bovine serum (FBS). Cells that grew out from the calvaria were passaged eight times to select cells with the ability to proliferate in culture before cloning was attempted.
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