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Acetylsalicylic acid desensitization in an allergic pregnant woman post-vascular scaffolds implantation. Eur Ann Allergy Clin Immunol 2024; 56:86-88. [PMID: 36515255 DOI: 10.23822/eurannaci.1764-1489.276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Summary The use of acetylsalicylic acid (ASA) desensitization for patients with coronary artery disease (CAD) is growing, but no data are available on desensitization protocol in patients with ASA sensitivity and CAD during pregnancy. This case report shows that ASA desensitization protocol during pregnancy could be safe and effective in a tertiary centre with a multidisciplinary team.
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Chemical composition and effects of ethanolic extract and gel of Cochlospermum regium (Schrank) Pilg. Leaves on inflammation, pain, and wounds. JOURNAL OF ETHNOPHARMACOLOGY 2023; 302:115881. [PMID: 36349588 DOI: 10.1016/j.jep.2022.115881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2022] [Revised: 10/17/2022] [Accepted: 10/25/2022] [Indexed: 06/16/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Cochlospermum regium is well-known as "Algodãozinho do cerrado" in folk Brazilian medicine, and is used to fight infections, inflammation and skin disorders. AIM OF THE STUDY To identify the phytochemical constituents and the effects of the ethanolic extract of C. regium leaves (EECR) on inflammation and pain, and the effects of C. regium gel (GEECR) on wound healing. MATERIALS AND METHODS Animals were treated with EECR (30-300 mg/kg) or GEECR (1.25 and 2.5%) and studies were conducted using carrageenan-induced pleurisy and paw edema tests, formalin-induced pain model, and excision wound model. RESULTS In total, 25 compounds, including quercitrin, methyl gallate, and 1,2,3,4,6-pentagalloylhexose, with highest detectability were identified. The treatments reduced leukocyte migration, nitric oxide production, protein extravasation, edema, mechanical hyperalgesia, pain in both phases (neurogenic and inflammatory), cold hypersensitivity, and improved wound closure and tissue regeneration. CONCLUSIONS The present findings established the anti-inflammatory, anti-nociceptive, and wound healing potential of the leaves of C. regium, confirming the potential therapeutic effect of this plant.
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Cochlospermum regium (Schrank) pilger leaf extract inhibit methicillin-resistant Staphylococcus aureus biofilm formation. JOURNAL OF ETHNOPHARMACOLOGY 2020; 261:113167. [PMID: 32730885 DOI: 10.1016/j.jep.2020.113167] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2020] [Revised: 07/04/2020] [Accepted: 07/06/2020] [Indexed: 06/11/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Cochlospermum regium, known as "algodãozinho", is an important plant belonging to Brazilian biodiversity used in traditional medicine to treat infections, wounds and skin conditions. AIM OF THE STUDY To assess the effects of aqueous and ethanolic extracts from C. regium leaves on methicillin-resistant Staphylococcus aureus planktonic cells and biofilm formation. MATERIAL AND METHODS The phytochemical characterization of the extracts was carried out by quantification of flavonoids, phenols and tannins and HPLC-DAD. Minimum inhibitory concentrations, cell viability, and enzyme activity inhibition were determined in planktonic cells exposed to C. regium extracts. The effect of the extracts on biofilms was assessed by quantifying colony-forming units (CFUs) and the extracellular matrix, and by visualizing the biofilm structure using scanning electron microscopy. RESULTS Leaf extract contents showed high concentration of phenols and the gallic and ellagic acids were identified. The extracts showed potent antimicrobial activities at concentrations ranging from 62.5-250 μg/mL, and decreased coagulase activity. In addition, the extracts prevented biofilm formation, and the aqueous extract completely inhibited its formation. CONCLUSIONS C. regium extracts stand out as promising alternative treatments for the prevention and treatment of methicillin-resistant Staphylococcus aureus infections.
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RNA-binding proteins RBM20 and PTBP1 regulate the alternative splicing of FHOD3. Int J Biochem Cell Biol 2018; 106:74-83. [PMID: 30468920 DOI: 10.1016/j.biocel.2018.11.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Revised: 10/29/2018] [Accepted: 11/19/2018] [Indexed: 12/12/2022]
Abstract
Regulation of alternative splicing events is an essential step required for the expression of functional cytoskeleton and sarcomere proteins in cardiomyocytes. About 3% of idiopathic dilated cardiomyopathy cases present mutations in the RNA binding protein RBM20, a tissue specific regulator of alternative splicing. Transcripts expressed preferentially in skeletal and cardiac muscle, including TTN, CAMK2D, LDB3, LMO7, PDLIM3, RTN4, and RYR2, are RBM20-dependent splice variants. In the present study, we investigated the RBM20 involvement in post-transcriptional regulation of splicing variants expressed by Formin homology 2 domain containing 3 (FHOD3) gene. FHOD3 is a sarcomeric protein highly expressed in the cardiac tissue and required for the assembly of the contractile apparatus. Recently, FHOD3 mutations have been found associated with heart diseases. We identified novel FHOD3 splicing variants differentially expressed in human tissues and provided evidences that FHOD3 transcripts are specific RBM20 and PTBP1 targets. Furthermore, we demonstrated that the expression of RBM20 and PTBP1 promoted the alternative shift, from inclusion to exclusion, of selected FHOD3 exons. These results indicate that RBM20 and PTBP1 play a role in the actin filament functional organization mediated by FHOD3 isoforms and suggest their possible involvement in heart diseases.
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In vitro antifungal activity of Myracrodruon urundeuva Allemão against human vaginal Candida species. AN ACAD BRAS CIENC 2017; 89:2423-2432. [PMID: 28746624 DOI: 10.1590/0001-3765201720170254] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Accepted: 05/04/2017] [Indexed: 11/22/2022] Open
Abstract
Myracrodruon urundeuva is a plant native to Brazil, which is used by the indigenous population for the treatment of candidiasis. The aims of this study were to evaluate the antifungal activity of extract against human vaginal Candida species and evaluate the possible toxicological activities of M. urundeuva. Initially, ethanol extracts, ethyl acetate fractions, and hydroalcoholic fractions of the bark and leaf of M. urundeuva were used to determine the minimum inhibitory concentration. The extracts that showed antifungal activity were characterized by liquid chromatography and subjected to toxicity assessment. Toxic, cytotoxic, genotoxic, and mutagenic testing were performed using Allium cepa and Ames assays with the ethanol extracts of the bark and leaves. Hemolytic activity was evaluated in erythrocytes and acute toxicity in rats. The ethanol bark extracts showed best activity against Candida albicans, C. krusei, and C. tropicalis ATCC (4-512 µg/mL). Chemical characterization indicated the presence of flavonoids and tannins in the extracts. Hemolytic activity, genotoxicity, and mutagenicity were not observed. The results of the Ames and A. cepa tests were also in agreement, ethanol bark extracts and ethanol leaf extracts of M. urundeuva showed absence of mutagenic activity. Similar results were observed in the A. cepa assay and acute toxicity test in rats. M. urundeuva bark extracts showed potential for the treatment of vaginal infections caused Candida species, as a topical.
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A novel mutation in ABCD1 unveils different clinical phenotypes in a family with adrenoleukodystrophy. J Clin Neurosci 2017; 43:175-177. [PMID: 28601575 DOI: 10.1016/j.jocn.2017.05.025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2017] [Accepted: 05/22/2017] [Indexed: 10/19/2022]
Abstract
X-linked adrenoleukodystrophy (X-ALD) is the most common peroxisomal disorder. The disease is the consequence of mutations in the ABCD1 gene that encodes the peroxisomal membrane protein ALDP which is involved in the transmembrane transport of very long-chain fatty acids. We describe a family with six members carrying a novel heterozygous mutation IVS4+2T>A (c.1393+2T>A) of the ABCD1 gene, highlighting the wide range of phenotypic manifestations of ALD and the importance of genetic screening before any pregnancy in asymptomatic women whose carrier status is unknown.
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Indagine sul profilo dell’utenza e sulla tipologia delle prestazioni erogate al pronto soccorso odontoiatrico di un ospedale milanese. DENTAL CADMOS 2013. [DOI: 10.1016/s0011-8524(13)70052-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Abstract
Osteoporosis and osteopenia are frequent complications of thalassemia major (TM) and intermedia (TI). Osteoporosis was found in 23/25 patients with TI and in 115/239 patients with TM. In TM, no association was found with specific polymorphisms in candidate genes (vitamin D receptor, estrogen receptor, calcitonin receptor, and collagen type 1 alpha 1). Osteoporosis in female patients with TM was strongly associated with primary amenorrhea (P < .0001), while in male patients with TM, hypogonadism was not significantly related to bone mineral density (BMD) (P = .0001). Low BMD was also associated with cardiomiopathy (P = .01), diabetes mellitus (P = .0001), chronic hepatitis (P = .0029), and increased ALT (P = .01).
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Relationship among VDR (BsmI and FokI), COLIA1, and CTR polymorphisms with bone mass, bone turnover markers, and sex hormones in men. Calcif Tissue Int 2002; 70:457-62. [PMID: 12016463 DOI: 10.1007/s00223-001-1088-9] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2001] [Accepted: 12/05/2001] [Indexed: 10/27/2022]
Abstract
Osteoporosis is a disease characterized by low bone mineral density (BMD) and up to 80% of its variance is under genetic control. Although osteoporosis is more frequent in women, one-third of hip fractures also occur in men. Much information on genetic factors and bone density has been obtained in women, but only a few studies have been performed in osteoporotic men. We have evaluated the relationship between polymorphisms for several candidate genes such as vitamin D receptor (VDR), collagen type Ia1 (COLIA1), and calcitonin receptor (CTR) in a sample of unrelated Italian men (n = 253, mean age 58.41 +/- 15.64 SD). We found no significant differences in BMD when subjects were stratified for their VDR (BsmI and FokI) and COLIA1 genotypes. BMD both at the lumbar spine and at the femoral neck were associated with polymorphism of CTR gene. The CC genotype of CTR gene had the lowest BMD value (P <0.05 and P <0.01 at the spine and hip, respectively) and its prevalence was significantly over-represented in the subgroup of men with prior hip or vertebral fracture as compared with controls (P = 0.004% c2 = 11.10). The men with the CC genotype also showed significantly lower body mass index (BMI), serum sex hormone binding globulin (SHBG), estradiol, total alkaline phosphatase-(total AP) and bone alkaline phosphatase (bone AP) levels and significantly higher free androgen index (FAI). In conclusion, the polymorphism of CTR gene but not VDR and COLIA1 is associated with osteoporosis incidence and the levels of alkaline phosphatase and estradiol. The lower BMD in CC genotype is apparently associated in males with depressed bone formation and lower estradiol levels.
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Rapid and efficient genotype analysis of the COL1a1 Sp1 binding site dimorphism, a genetic marker for bone mineral density. Mol Cell Probes 2002; 16:73-5. [PMID: 12005451 DOI: 10.1006/mcpr.2001.0401] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A biallelic G/T polymorphism within the first intron of COL1A1 gene at a recognition site for the transcription factor Sp1 has been shown to be significantly related to bone mass and osteoporotic fracture. To date this polymorphism has been detected by conventional genomic DNA amplification followed by restriction enzyme digestion and polyacrylamide gel electrophoresis. We have designed a rapid and efficient genotyping method based on allele-specific polymerase chain reaction
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Stickler syndrome and vitreoretinal degeneration: correlation between locus mutation and vitreous phenotype. Apropos of a case. Graefes Arch Clin Exp Ophthalmol 2001; 239:316-9. [PMID: 11450497 DOI: 10.1007/s004170100286] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND Autosomal dominant vitreoretinopathies are characterized by genetic heterogeneity. Structural mutations in COL2A1 are the most frequent cause of Stickler syndrome with ocular involvement. The affected patients have a characteristic vitreous alteration, so-called membranous vitreous, or type 1 vitreous phenotype. Recently a novel mutation in the gene encoding the alpha 1 chain of type XI collagen (COL11A1) was reported in rare Stickler pedigrees, with a different, so-called beaded or type 2 vitreous phenotype. METHODS Five patients of an Italian family affected by high myopia, high frequency of retinal detachment, and other systemic stigmata evocative of Stickler syndrome (flat midface, depressed nasal bridge, short nose, spondyloepiphyseal dysplasia and osteoarthritis) were studied. Genetic investigations were also performed, considering three candidate loci for Stickler syndrome and Wagner syndrome (COL2A1, COL11A1, WGN1). RESULTS Segregation analysis was performed utilizing polymorphic markers. COL2A1 and WGN1 segregations were excluded; COL11A1 showed concordance with the disease. The vitreous phenotype of the family was a typical type 1 or "membranous" vitreous, although all the previously reported COL11A1-related Stickler syndromes had always shown the type 2 or "beaded" vitreous phenotype. CONCLUSIONS The clear presence of the type 1 or "membranous" vitreous phenotype in our family, despite the probable mutation in the COL11A1 gene, suggests greater phenotypical heterogeneity and a more extensive mutation spectrum, even of the COL11A1 gene, than previously thought, explaining the basis for the different vitreous phenotypes seen in Stickler syndrome.
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Autosomal dominant benign recurrent intrahepatic cholestasis (BRIC) unlinked to 18q21 and 2q24. AMERICAN JOURNAL OF MEDICAL GENETICS 2000; 95:450-3. [PMID: 11146465 DOI: 10.1002/1096-8628(20001218)95:5<450::aid-ajmg8>3.0.co;2-v] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Benign recurrent intrahepatic cholestasis (BRIC) is an autosomal recessive liver disease characterized by multiple episodes of cholestasis without progression to chronic liver disease. On the basis of recent evidence of locus heterogeneity, we studied 19 subjects (7 affected members) of a BRIC family. Male-to-male transmission and the presence of affected females suggested autosomal dominant inheritance. Blood samples were collected after informed consent. Subjects were genotyped by using markers mapping to 18q and 2q24 region, respectively, where the genes FIC1 and FIC2 have been mapped. Segregation of haplotypes excluded the two regions in our family. These findings suggest further genetic heterogeneity of the origin of BRIC.
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Transduced fibroblasts and metachromatic leukodystrophy lymphocytes transfer arylsulfatase A to myelinating glia and deficient cells in vitro. Hum Gene Ther 1998; 9:2111-9. [PMID: 9759937 DOI: 10.1089/hum.1998.9.14-2111] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Metachromatic leukodystrophy (MLD) is a lysosomal storage disease, caused by deficiency of arylsulfatase A (ASA), that manifests primarily in the white matter of the nervous system. Currently, no specific treatment exists that will reverse its fatal outcome. Replacement therapy has been hampered by the blood-brain barrier (BBB). To circumvent this problem we designed an ex vivo gene therapy strategy that includes the retrovirus-mediated ASA transduction of cells, such as activated lymphocytes, that are able to traverse the BBB or other membranes of the CNS. For this purpose, two recombinant retroviruses based on the pLXSN vector were produced, containing the wild-type ASA cDNA or a pseudodeficiency ASA cDNA, which encodes a smaller enzyme with normal activity. After transduction, ASA activity increased more than 100-fold in fibroblasts from an MLD patient. Furthermore, ASA-transduced MLD PBLs expressed 30 times higher ASA activity when compared with control PBLs. Moreover, cell culture experiments demonstrated that transduced fibroblasts could efficiently transfer ASA to deficient cells across a transwell barrier, whereas transduced MLD lymphocytes could transfer ASA to deficient fibroblasts only by direct cell-to-cell contact. Finally, ASA was taken up by normal oligodendrocytes and Schwann cells, the target myelinating glial cells for therapy in MLD. These data suggest possible short-term strategies for transfer of ASA into the CNS via transduced autologous cells while long-term strategies, related to autologous transduced bone marrow transplant, take effect in patients.
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Abstract
beta-Hexosaminidase gene mutations were analyzed in two adult-onset Sandhoff disease Italian patients by PCR analysis of a common known mutation (delta 5') and by heteroduplex analysis of genomic and RT-PCR DNA fragments, covering the whole gene. The patients' genotypes were delta 5'/C1214%, and G890A/C1214T, respectively. As mutation C1214T (Pro405Leu) is also present in the other two late-onset cases so far described, we suggest that C1214T is a common mutation in this type of Sandhoff disease. Mutation G890A (Cys297Tyr) is a novel mutation which presumably causes altered processing of the pro beta chain.
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Determination of a new collagen type I alpha 2 gene point mutation which causes a Gly640 Cys substitution in osteogenesis imperfecta and prenatal diagnosis by DNA hybridisation. J Med Genet 1994; 31:965-8. [PMID: 7891382 PMCID: PMC1016701 DOI: 10.1136/jmg.31.12.965] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The molecular defect responsible for a sporadic case of extremely severe (type II/III) osteogenesis imperfecta was investigated. The mutation site was localised in the collagen type I pro alpha 2 mRNA molecules produced by the proband's skin fibroblasts by chemical cleavage of mismatch in heteroduplex nucleic acids. Reverse transcription-polymerase chain reaction DNA amplification, followed by cloning and sequencing, showed heterozygosity for a G to T transversion in the first nucleotide of exon 37 of the COL1A2 gene, which led to a cysteine for glycine substitution at position 640 of the triple helical domain. This newly characterised mutation is localised in a domain which contains several milder mutations, confirming that glycine substitutions within the alpha 2(I) chain do not follow a linear gradient pattern for genotype to phenotype correlations. In a subsequent pregnancy, absence of the G2327T mutation in the fetus was shown by allele specific oligonucleotide hybridisation to the trophoblast derived fibroblast mRNA after reverse transcription and in vitro amplification. (The nucleotide number assigned to the mutant base was inferred from the numbering system devised by the Osteogenesis Imperfecta Analysis Consortium (The OIAC Newsletter, 1 April 1994).)
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A base substitution at IVS-19 3'-end splice junction causes exon 20 skipping in pro alpha 2(I) collagen mRNA and produces mild osteogenesis imperfecta. Hum Genet 1994; 93:681-7. [PMID: 8005592 DOI: 10.1007/bf00201570] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Molecular investigations on a young patient and her family were undertaken to identify the molecular defect responsible for a mild form of osteogenesis imperfecta (OI) with blue sclerae, dentinogenesis imperfecta and joint laxity. Analysis of collagenous proteins from the proband's fibroblasts showed the presence of two populations of alpha 2(I) chains, one normal and one migrating faster on SDS gels, thereby suggesting deletion of amino acid sequences. The faster migrating chains were retained mainly in the cell layer and not found in the extracellular matrix deposited by cultured fibroblasts. Chemical cleavage of mismatch (CCM) analysis on the patient's pro alpha 2(I) mRNA: normal cDNA heteroduplexes localized the molecular defect. cDNA sequencing revealed a deletion of exon 20 (54 bp) in about half of the molecules. Genomic DNA sequencing revealed heterozygosity for a G-to-C transversion of the last nucleotide of intron 19, which changed the 3' consensus splicing site. As a consequence pro alpha 2(I)mRNA was abnormally spliced from the last codon of exon 19 to the first codon of exon 21. To our knowledge, this is the first acceptor site mutation so far described in an OI patient. Restriction analysis indicated that the mutation was present also in three other affected family members. The full sequence of COL1A2 introns 19 and 20 are reported.
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Substitution of an aspartic acid for glycine 700 in the alpha 2(I) chain of type I collagen in a recurrent lethal type II osteogenesis imperfecta dramatically affects the mineralization of bone. J Biol Chem 1994; 269:14751-8. [PMID: 8182080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
We describe a new dominant mutation of type I collagen responsible for a recurrent lethal osteogenesis imperfecta. Dermal cultured fibroblasts of the proband produced both normal and overmodified type I collagen chains. Previous results (Cohen-Solal, L., Bonaventure, J., and Maroteaux, P. (1991) Hum. Genet. 87, 297-301) and cyanogen bromide peptide mapping after non-equilibrium pH gradient gel electrophoresis indicated that the anomaly was a charge mutation localized in the alpha 2CB3-5A. The mutation was identified as a G to A transition in the COL1A2 gene, which converts glycine 700 to aspartic acid in the alpha 2I chain. This mutation caused the abolition of a ScrFI site, which was also absent in the suspected mosaic father. Pulse-chase experiment showed intracellular retention and increase of the degradation of the synthesized collagen. To understand more directly the tissue defect in osteogenesis imperfecta, skin and especially bone were studied with biochemical and transmission electron microscopy techniques. Collagen matrix of both tissues was dramatically decreased and presented a retarded migration, showing that abnormal molecules were incorporated during the fibrillogenesis. The abnormal collagen mostly remained within the fibroblasts and osteoblasts, which presented typical features of intracellular retention. We observed the presence of spheritic aggregates of mineral, unrelated to the scarce and thin collagen fibrils, in bone. Such abnormal mineralization could be the consequence not only of the decrease of the collagen content but more importantly of the inability of the abnormal molecules to form an organized network necessary to the deposition of apatite crystallites.
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Osteogenesis imperfecta and type-I collagen mutations. A lethal variant caused by a Gly910-->Ala substitution in the alpha 1 (I) chain. EUROPEAN JOURNAL OF BIOCHEMISTRY 1993; 211:415-9. [PMID: 7679635 DOI: 10.1111/j.1432-1033.1993.tb17565.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
In this study we describe a new dominant point mutation in COL1A1 causing a lethal form of Osteogenesis imperfecta (type II B). Dermal cultured fibroblasts from the proband were shown to produce both normal and heavily overmodified type-I collagen. The mutation introduced a local conformational perturbation, which causes abnormal exposure of arginine residues; the triple helical domain was susceptible to trypsin digestion even at 30 degrees C. The chains bearing the point mutation were poorly secreted and short-term pulse experiments showed that the extensive intracellular retention of mutant trimers also impaired the secretion of normal chains. The molecular defect was localized in a COL1A1 allele by cloning and sequencing a cDNA region corresponding to the CB6 peptide. A G to C transversion which causes the substitution in the triple helical region of Gly910 with alanine was found. The mutation also causes the disappearance of a MspI-recognition site at nucleotide 3263 of the pro alpha 1 (I) coding sequence. Restriction analysis, along with the biochemical screening of collagens, allowed us to perform prenatal diagnosis on cells from chorionic-villus sampling and to exclude the recurrence of the mutation in the sibling.
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Haplotype analysis of collagen type I genes in the general population and in osteogenesis imperfecta families. AMERICAN JOURNAL OF MEDICAL GENETICS 1993; 45:217-22. [PMID: 8096115 DOI: 10.1002/ajmg.1320450213] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The allele frequencies of 2 new polymorphic markers of collagen type I proalpha 1 (COL1A1) and proalpha 2 (COL1A2) genes were determined in a random sample of chromosomes by polymerase chain reaction. The minor allele frequencies were 0.27 for COL1A1/+88Mn1I, and 0.39 for COL1A2/1446 PvuII RFLPs, respectively. These 2 polymorphisms increased the combined (PIC) values we previously determined in the Italian population with Southern blotting procedures, from 0.71 at the COL1A1 locus to 0.81, and from 0.73 at the COL1A2 locus to 0.88, respectively. With a combination of these markers, we have carried out the segregation analysis of 4 new families in which osteogenesis imperfecta (OI) segregated as a dominant trait. The disease segregated with COL1A1 in 2 OI type I families, and with COL1A2 in one OI type IV family. In one OI type I family the concordant locus was uncertain. This analysis was extended to the 7 dominant OI families we previously reported: in 3 out of 11 pedigrees either locus still could not be excluded, indicating the need for more genetic markers. COL1A1 and COL1A2 haplotype frequencies were compared in normal and OI chromosomes: no preferential association of the disease with a given haplotype was detected. The correlation between affected locus and clinical aspects is discussed.
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Mild dominant osteogenesis imperfecta with intrafamilial variability: the cause is a serine for glycine alpha 1(I) 901 substitution in a type-I collagen gene. Hum Genet 1992; 89:480-4. [PMID: 1634225 DOI: 10.1007/bf00219169] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The molecular defect responsible for a case of mild osteogenesis imperfecta (OI) with repeated femoral fractures was investigated. The proband and his mother, who presented minor OI signs but no bone fractures, were shown to produce normal and abnormal type-I procollagen molecules in their dermal fibroblasts. The molecular defect was localized in about half of the proband's pro alpha 1(I) mRNA molecules by chemical cleavage with piperidine of hydroxylamine-reacted mRNA:cDNA heteroduplexes. The corresponding region was reverse-transcribed and amplified by polymerase chain reaction (PCR). Cloning and sequencing of the amplified products revealed in both subjects a G-to-A transition in the first base of codon 901 of the alpha 1(I) triple helical domain, which led to a serine for glycine substitution. Allele-specific oligonucleotide hybridization to amplified genomic DNA from fibroblasts and leukocytes confirmed the heterozygous nature of both patients and proved the absence of mosaicism. The presence of the mutation was excluded in other healthy family members, who were reported to have bluish selerae. The mild phenotypic outcome of this newly characterized mutation contradicts previous findings on glycine substitutions in the C-terminal region of collagen triple helix, most of which caused lethal OI.
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A de novo G to T transversion in a pro-alpha 1 (I) collagen gene for a moderate case of osteogenesis imperfecta. Substitution of cysteine for glycine 178 in the triple helical domain. J Biol Chem 1991; 266:1872-8. [PMID: 1988452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Cultured fibroblasts from a patient affected with a moderate form of osteogenesis imperfecta were defective for the synthesis of type I collagen molecules; about half of the alpha 1(I) chains contained a cysteine residue in the triple helical domain and a disulfide link formed when two mutant alpha 1(I) chains were incorporated into a type I collagen heterotrimer. The proband's parents were clinically and biochemically normal. The cysteine was localized within peptide alpha 1(I)CB8 between residues 170 and 200 of the triple helical domain using a chemical procedure with 2-nitro-5-thiocyanobenzoic acid (Tenni, R., Rossi, A., Valli, M., Mottes, M., Pignatti, P. F., and Cetta, G. (1990) Matrix 10, 20-26). Type I procollagen heterotrimers containing either one or two mutant chains showed (i) a slight abnormality in secretion from cells; (ii) a low degree of post-translational overmodifications; (iii) the same, but lower than normal, thermal stability. Total RNA was isolated from the proband's dermal fibroblast cultures, and cDNAs for pro-alpha 1(I) were prepared d using total RNA. A portion of cDNA, coding for the region encompassing residues 119-193 of alpha 1(I) triple helical domain, was amplified by polymerase chain reaction. A single base pair mismatch was identified by chemical cleavage of DNA.DNA heteroduplexes, indicating a possible substitution of a guanine in the triplet coding for glycine 178 or 181. The same unique mismatch was detected by chemical cleavage in about one-half of the molecules in heteroduplexes formed between patient's pro-alpha 1(I) mRNAs and a normal cDNA probe. The amplified products were cloned and sequenced, confirming the heterozygous nature of the patient and demonstrating the presence and the location of a missense mutation; a single T for G substitution was found in the first base of the triplet coding for residue 178 of alpha 1(I) triple helical domain, leading to a cysteine for glycine substitution. Allele-specific oligonucleotide hybridization to amplified DNA confirmed a de novo point mutation in the proband's genome. The findings in this patient are in accord with the phenotypic gradient model, which correlates the localization of the structural defect with the clinical outcome of osteogenesis imperfecta. The mutant protein has some properties that differ from the caused by the cysteine for glycine 175 substitution, suggesting a direct influence of the neighboring amino acids on the effects of the mutation.
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