PubMed Health⌕ Search

Biomedical subjects

P Narcisi

Publications and source records attributed to P Narcisi.

At least 19 recordsLinked to original sources

Personal experience of the treatment of ruptured aortic aneurysms. The prognostic evaluation of some parameters.

BACKGROUND: The rupture of an aortic aneurysm is the most frequent and most severe complication, with an incidence of approximately 20-40/100,000 persons each year. The aim of this study was to identify the preoperative, intraoperative and postoperative factors that may influence the mortality rate. METHODS: Between January 1996 and December 1999 145 patients underwent emergency abdominal aortic repair surgery. One hundred and twenty-three patients represented a ruptured AAA and 22 a fissured aneurysm. One hundred and thirty-one patients were males and 14 were females; their mean age was 75+/-5.06 years. We selected a number of parameters after a review of the international literature and these were analysed in the two classes of survivors. No statistical analyses were performed on fissured aneurysms owing to the scant number of cases examined. RESULTS: Mortality was 41.4% (44.7% in ruptured aneurysms alone). The following were negative preoperative prognostic factors: old age, hypertension, ASA V, intraoperative anuria and platelet count <100,000. Intraoperative factors included: hypotension, cardiac arrest, onset of anuria, aortic clamping in more than one site, duration of surgery, quantity of RBC and plasma transfused. The main postoperative variables correlated to mortality were: hypotension, hypothermia, onset of anuria, need for further transfusions, high creatinine levels. CONCLUSIONS: Rapid intervention can minimise mortality in structures with expert teams of surgeons and anesthetists experienced in treating this type of pathology.

Age Factors↗

Disappearance of central pain following iatrogenic stroke.

An exceptional case of long-standing central pain temporarily relieved by a focal stroke in the primary somatosensory area is reported. This case highlights the focal nature of central pain mechanisms and the possible value of selective subparietal leukotomies in the management of central pain.

Analgesics↗

COL3A1 mutations cause variable clinical phenotypes including acrogeria and vascular rupture.

We have recently analysed by histological, protein and molecular DNA techniques 23 mutations of the collagen III gene (COL3A1), most of which cause premature arterial fragility, thin skin and variants of vascular Ehlers-Danlos syndrome. There were 14 glycine substitutions between residues 637 and 1021, eight exon skips between exons 7 and 45 and one small inframe deletion. The glycine substitutions produce a gradient of increasingly abnormal clinical phenotypes from exons 36 to 49 while the clinical severity of exon skips is much more variable. Each mutation is private for the affected family or individual concerned having the potential for early prenatal diagnosis and prevention.

Adolescent↗

A family with Ehlers-Danlos syndrome type III/articular hypermobility syndrome has a glycine 637 to serine substitution in type III collagen.

Ehlers-Danlos syndrome (EDS) is a heterogeneous group of heritable disorders of connective tissue. The type III variety is characterized by joint hypermobility and minor hyperextensibility and softness of the skin. While collagen fibril structure has been shown to be abnormal in such patients, the underlying molecular defect(s) has not been determined. Here we characterize the first mutation found in a family with EDS III. Analysis of cultured fibroblasts from the affected family revealed intracellular retention of type III collagen. This is usually a biochemical characteristic of EDS IV, caused by mutations of COL3A1. Analysis of the cDNA sequence in this EDS III family revealed a glycine to serine mutation at amino acid residue 637 of the type III collagen molecule. This was confirmed by allele-specific oligonucleotide hybridization against amplified genomic DNA. Thus mutations of type III collagen can cause either EDS IV or EDS III. Two affected family members had virtually normal skin and so more closely resembled the phenotype of articular hypermobility syndrome.

Adult↗

Single base mutation that substitutes glutamic acid for glycine 1021 in the COL3A1 gene and causes Ehlers-Danlos syndrome type IV.

The proposita described here was a 24-year-old woman with an acrogeric form of the Ehlers-Danlos syndrome including a massive dissecting aortic aneurysm. She was found to have a single-base mutation that substituted glutamic acid for glycine at amino acid position 1021 in the triple-helical domain of the type III procollagen. It is the most carboxy-terminal single-base mutation characterized to date in the COL3A1 gene. Analysis of medium and cell layer proteins from proposita's cultured skin fibroblasts showed that the mutant protein was poorly secreted, migrated more slowly on a polyacrylamide gel, and was partially unstable at +25 degrees C to brief digestion with trypsin.

Adult↗

A T+6 to C+6 mutation in the donor splice site of COL3A1 IVS7 causes exon skipping and results in Ehlers-Danlos syndrome type IV.

Ehlers-Danlos syndrome type IV is usually caused by mutations in COL3A1, the gene coding for type III collagen. In a woman with a milder form of this disease, analysis of type III collagen synthesised by her cultured skin fibroblasts showed an apparently shorter form of the protein. Amplification of overlapping cDNAs, encoding the triple helical region of the molecule, showed a deletion near the 5' end of the gene. Sequencing showed that exon 7 was missing from the cDNA sequence. Analysis of genomic DNA showed that this was the result of a T+6 to C+6 mutation in the donor splice site of intron 7. The proband's parents and 35 normal controls were homozygous for T+6 at this position, indicating that the C+6 mutation was causative.

Adult↗

The substitution of glycine 661 by arginine in type III collagen produces mutant molecules with different thermal stabilities and causes Ehlers-Danlos syndrome type IV.

Previous studies have shown that Ehlers-Danlos syndrome type IV (EDS IV) is caused by mutations of type III collagen (COL3A1). Here we have characterised the most amino-terminal glycine substitution so far described in a patient with EDS IV. A combination of peptide mapping and chemical cleavage analysis of cDNA localised the mutation in cyanogen bromide peptide CB5. Sequence analysis showed a G to A mutation, converting glycine 661 to arginine, which was a new dominant mutation. Analysis of type III collagen secreted by cultured fibroblasts showed an overmodified mutant protein with normal thermal stability. However, the intracellularly retained form melted 2 degrees C lower than normal. This indicated that molecules resulting from the same mutation can differ in their thermal stabilities.

Arginine↗

A single base mutation in the gene for type III collagen (COL3A1) converts glycine 847 to glutamic acid in a family with Ehlers-Danlos syndrome type IV. An unaffected family member is mosaic for the mutation.

Ehlers-Danlos syndrome type IV, an inherited connective tissue disease, is usually caused by mutations in the gene for type III collagen. Here, we describe a glycine to glutamic acid substitution in a patient with this syndrome. Previous studies had shown that fibroblasts from the patient, his mother and brother secreted a reduced amount of type III collagen and also produced an overmodified form of the protein that was preferentially retained intracellularly. Peptide mapping experiments indicated that the mutation was located within cyanogen bromide peptide 9. This was supported by chemical cleavage analysis and sequencing of cDNA encoding this region. Allele-specific oligonucleotide hybridisation of genomic DNA confirmed that a G to A mutation converted Gly 847 to Glu. The mutation was present in two other affected family members and also in a third, who was clinically unaffected. Further analysis of this unaffected individual revealed reduced mutant:normal ratios in DNA obtained from both blood and hair samples, showing that she was mosaic for the mutation.

Amino Acid Sequence↗

A 27-bp deletion from one allele of the type III collagen gene (COL3A1) in a large family with Ehlers-Danlos syndrome type IV.

A large family with Ehlers-Danlos syndrome type IV (EDS IV) has previously been described. Unlike most cases of EDS IV, fibroblasts from affected members secreted near normal amounts of type III collagen. We have localized the mutation in this family to the CB5 peptide of type III collagen, by using both protein and cDNA mapping techniques. Sequence analysis of cDNA revealed a 27-bp deletion within exon 37, a deletion that removed nine amino acids and maintained the Gly-X-Y repeat of the collagen helix. Further sequencing of genomic DNA confirmed its location, and amplification of DNA from family members showed that it was absent in unaffected individuals but present in all the affected individuals tested. This deletion is flanked by two short direct repeats of CTCC; it may have arisen by slipped mispairing, and has subsequently been transmitted to all affected family members.

Alleles↗

Detection and characterisation of an overmodified type III collagen by analysis of non-cutaneous connective tissues in a patient with Ehlers-Danlos syndrome IV.

The clinical and biochemical observations in a patient with a mild form of Ehlers-Danlos syndrome (EDS) type IV are described. The patient's skin fibroblasts produced markedly diminished amounts of type III collagen. SDS-polyacrylamide gel electrophoresis of collagens produced by cells obtained from other, non-cutaneous tissues showed two forms of collagen alpha 1(III) chains, a normal and a slow migrating, mutant form. Further analysis confirmed that the type III collagen molecules containing mutant alpha chains which were overmodified had a lower thermal stability and were poorly secreted into the extracellular medium. The protein defect was mapped by in situ cyanogen bromide digestion and was located in alpha 1(III) CB9, the C-terminal peptide of the collagen triple helix. This study shows that non-cutaneous connective tissues can be a useful source for the study of type III collagen defects in patients with EDS type IV.

Cells, Cultured↗

Characterisation of a glycine to valine substitution at amino acid position 910 of the triple helical region of type III collagen in a patient with Ehlers-Danlos syndrome type IV.

We have studied a patient with Ehlers-Danlos syndrome type IV. Protein mapping studies of her type III collagen had indicated that cyanogen bromide fragment 9 contained the site of the mutation. Here we describe the mapping of this region for a single base mutation using a chemical modification and cleavage technique. Sequence analysis of cDNA showed a G to T mutation resulting in the substitution of glycine 910 by valine. This was confirmed by allele specific oligonucleotide hybridisation to the proband's genomic DNA.

Alleles↗

Prenatal diagnosis and prevention of inherited abnormalities of collagen.

There is now strong evidence for the implication of collagen alpha 1(I), alpha 2(I) and alpha 1(III) mutations in many forms of osteogenesis imperfecta and inherited arterial aneurysms (Ehlers Danlos syndrome type IV). A sizeable proportion of these disorders have detectable abnormalities by conventional protein chemistry, immunofluorescence, or more sophisticated DNA analysis. Everyone of them with specific defects or with linkage to appropriate gene markers is therefore amenable to prevention using conventional prenatal diagnosis by chorionic villus biopsy (with fibroblast culture), fetoscopic biopsy (with fibroblast culture), ultrasound diagnosis of the severely deformed fetus, or gene linkage studies by chorionic villus biopsy or amniocentesis. Already many collagen alpha 1(I), alpha 2(I) and alpha 1(III) mutations have been characterized including point mutations, small and large deletions and regulatory mutations. Many others are likely to be rapidly studied by exploiting recent advances in DNA technology, and other strong candidate genes include collagen II (some chondrodystrophies), collagen VI (certain arterial and cardiovascular diseases) and collagen VII (dystrophic epidermolysis bullosa). Other important common diseases are likely to include osteoporosis, osteoarthritis and cerebral aneurysms. A detailed review is provided of collagen interstitial genes and proteins, together with a description of the various forms of osteogenesis imperfecta and Ehlers Danlos syndrome in which either collagen alpha 1(I), alpha 2(I) or alpha 1(III) mutations have been identified. Appropriate restriction length polymorphisms (RFLPs) useful in identifying carriers of these mutant genes are also described.

Collagen↗

Linkage of a polymorphic marker for the type III collagen gene (COL3A1) to atypical autosomal dominant Ehlers-Danlos syndrome type IV in a large Belgian pedigree.

We have examined a large family in which eleven members have a form of autosomal dominant Ehlers-Danlos syndrome type IV. Analysis of fibroblast cultures from affected individuals showed a partial deficiency of type III collagen production. The protein produced was, however, normal in all aspects examined. Using a restriction site polymorphism associated with the structural gene for human type III collagen (COL3A1), we have found tight linkage between the low frequency polymorphic allele and the clinical expression of the disease (lod = 3.86 at 0 = 0), identifying the type III collagen gene as the disease locus.

Adult↗

Detection of type III collagen in skin fibroblasts from patients with Ehlers-Danlos syndrome type IV by immunofluorescence.

Immunofluorescence showed that cultured skin fibroblasts from 15 out of 17 patients with Ehlers-Danlos syndrome type IV retained abnormal amounts of type III collagen within the cytoplasm. This was not shown by fibroblasts from normal subjects or from patients with other inherited connective tissue diseases. The diagnosis of Ehlers-Danlos syndrome type IV may be facilitated by this finding.

Adult↗

Clinical presentations of Ehlers Danlos syndrome type IV.

Ehlers Danlos syndrome type IV is an often lethal disease caused by various mutations of type III collagen genes. It presents in infancy and childhood in several ways, and the symptoms and signs include low birth weight, prematurity, congenital dislocation of the hips, easy inappropriate bruising (sometimes suspected as child battering), and a diagnostic facial phenotype. These features predict a lethal adult disease often complicated by fatal arterial rupture in early or middle adult life. Most affected patients can be diagnosed from radiolabelled collagen protein profiles by polyacrylamide gel electrophoresis. Prenatal diagnosis by specific type III collagen restriction fragment length polymorphisms is possible in some families, and will become increasingly important. Prenatal diagnosis and prevention of the disease in selected families is already possible and will be widely available in the future.

Adolescent↗

Spontaneous carotid cavernous fistula in Ehlers Danlos syndrome.

A patient is described with Ehlers Danlos syndrome presenting with spontaneous carotid cavernous fistula, in whom there was biochemical evidence for defective type III collagen synthesis. Despite the risks associated with arterial manipulation, the fistula was successfully closed by interventional neuroradiology and the patient has since remained well. This outcome is in contrast with the results in previous reports.

Adult↗