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C Boileau

Publications and source records attributed to C Boileau.

At least 55 records · Page 3Linked to original sources
PubMed1994

A second locus for Marfan syndrome maps to chromosome 3p24.2-p25.

Marfan syndrome (MFS) is an autosomal dominant connective-tissue disorder characterized by skeletal, ocular and cardiovascular defects of highly variable expressivity. The diagnosis relies solely on clinical criteria requiring anomalies in at least two systems. By excluding the chromosome 15 disease locus, fibrillin 1 (FBN1), in a large French family with typical cardiovascular and skeletal anomalies, we raised the issue of genetic heterogeneity in MFS and the implication of a second locus (MFS2). Linkage analyses, performed in this family, have localized MFS2 to a region of 9 centiMorgans between D3S1293 and D3S1283, at 3p24.2-p25. In this region, the highest lod score was found with D3S2336, of 4.89 (theta = 0.05). By LINKMAP analyses, the most probable position for the second locus in MFS was at D3S2335.

Adult↗
PubMed1994

French myotonic dystrophy families show expansion of a CTG repeat in complete linkage disequilibrium with an intragenic 1 kb insertion.

The molecular basis of myotonic dystrophy (DM) has been characterised. All DM mutations characterised to date appear as an unstable elongation of a fragment containing a tandem repeat of a CTG motif, which can be visualised in both EcoRI and BamHI digests. It has been shown that the fragment is polymorphic in the normal population. Another 1 kb insertion/deletion polymorphism located near the unstable CTG repeat region has been identified. The 1 kb insertion allele is present in all DM patients. These different polymorphic systems can be distinguished using cDNA25 and BamHI, because this enzyme cuts between the site of the 1 kb insertion and the CTG repeat. We thus haplotyped DM patients from 72 French families and clearly showed that all chromosomes (100%) with the DM mutation carried the 1 kb insertion as well. In addition to this association, we detected significant linkage disequilibrium between the DM locus and D19S63 for which allelic frequencies were different from other European populations. Our results in the French DM population are thus in agreement with the hypothesis that the CTG expansion occurred on one or a few ancestral chromosomes carrying the large 1 kb insertion allele.

Alleles↗
PubMed1993

Two new polymorphisms in the coding sequence of the LDL receptor (LDLR) gene.

We identified by polymerase chain reaction/single-strand conformation polymorphism analysis two unreported polymorphisms in the low density lipoprotein receptor gene, located in exons 11 and 15. The exon 15 sequence variation can also be readily detected since it abolishes an MspI site.

DNA Mutational Analysis↗
PubMed1993

Autosomal dominant Marfan-like connective-tissue disorder with aortic dilation and skeletal anomalies not linked to the fibrillin genes.

We describe a large family with a connective-tissue disorder that exhibits some of the skeletal and cardiovascular features seen in Marfan syndrome. However, none of the 19 affected individuals displayed ocular abnormalities and therefore did not comply with recognized criteria for this disease. These patients could alternatively be diagnosed as MASS (mitral valve, aorta, skeleton, and skin) phenotype patients or represent a distinct clinical entity, i.e., a new autosomal dominant connective-tissue disorder. The fibrillin genes located on chromosomes 15 and 5 are clearly involved in the classic form of Marfan syndrome and a clinically related disorder (congenital contractural arachnodactyly), respectively. To test whether one of these genes was also implicated in this French family, we performed genetic analyses. Blood samples were obtained for 56 family members, and four polymorphic fibrillin gene markers, located on chromosomes 15 (Fib15) and 5 (Fib5), respectively, were tested. Linkage between the disease allele and the markers of these two genes was excluded with lod scores of -11.39 (for Fib15) and -13.34 (for Fib5), at theta = .001, indicating that the mutation is at a different locus. This phenotype thus represents a new connective-tissue disorder, overlapping but different from classic Marfan syndrome.

Adult↗
PubMed1992

Diagnosis of Duchenne and Becker muscular dystrophies by polymerase chain reaction. A multicenter study.

OBJECTIVE--To assess the efficiency, reliability, and ease of use of DNA diagnosis for Duchenne and Becker muscular dystrophies (DMD/BMD) using the polymerase chain reaction (PCR). DESIGN--DNA from the patients was screened for deletion mutations using multiplex PCR, and the results were compared with those obtained by Southern blot analysis. The PCR multiplex reaction detects nine specific "hot-spot" exons in the dystrophin gene while the Southern analysis detects 66 specific dystrophin gene restriction fragments. The multiplex reaction requires 50-fold less DNA than Southern analysis and thus is considerably more sensitive. SETTING--Fourteen university-affiliated and private genetic disease diagnostic laboratories. PATIENTS--Male patients with clinical signs of DMD/BMD. Cases were selected for analysis randomly, without knowledge of whether a deletion was present within the dystrophin gene. MAIN OUTCOME MEASURES--The percentage of cases that were detectable by multiplex PCR in comparison with Southern analysis, the frequency, extent, and location of the detected deletion mutations. In some cases, duplication mutations were monitored. RESULTS--The accuracy of a single PCR multiplex amplification (nine exons) was compared with Southern analysis with 10 cDNA probes that cover the full length of the gene. The multiplex PCR analytic method detected 82% of those deletions detected by Southern analysis methods. In one of 745 analyses, the multiplex method suggested a single exon deletion, which was not confirmed by Southern analysis, representing a false-positive rate of 0.013%. CONCLUSIONS--Multiplex PCR represents a sensitive and accurate method for deletion detection of 46% of all cases of DMD/BMD. The method requires 1 day for analysis, is easy to perform, and does not use radioactive tracers. As such, multiplex PCR represents an efficient and rapid method for prenatal or postnatal diagnosis of DMD/BMD.

Blotting, Southern↗
PubMed1992

Parental origin and germline mosaicism of deletions and duplications of the dystrophin gene: a European study.

Knowledge about the parental origin of new mutations and the occurrence of germline mosaicism is important for estimating recurrence risks in Duchenne (DMD) and Becker muscular dystrophy (BMD). However, there are problems in resolving these issues partly because not all mutations can as yet be directly detected, and additionally because genetic ratios are very sensitive to ascertainment bias. In the present study, therefore, analysis was restricted to currently detectable mutations (deletions and duplications) in particular types of families which tend to be rare. In order to obtain sufficient data we pooled results from 25 European centers. In mothers of affected patients who were the first in their family with a dystrophin gene deletion or duplication, the ratio between the paternal and the maternal origin of this new mutation was 32:49 (binomial test P = 0.075) for DMD. In five BMD families the ratio between paternal and maternal origin of new mutations was 3:2. Recurrence risk because of maternal germline mosaicism was studied in sisters or subsequent sibs of isolated cases with an apparently new detectable mutation. In 12 out of 59 (0.20; 95% CI 0.10-0.31) transmissions of the risk haplotype the DMD mutation was transmitted as well. No recurrences were found in nine BMD families.

Chromosome Deletion↗
PubMed1992

A linkage map of 10 loci flanking the Marfan syndrome locus on 15q: results of an International Consortium study.

Members of an International Consortium for Linkage Analysis of the Marfan Syndrome (MFS1) have pooled data for joint analysis in an attempt to determine the precise location of the MFS1 gene and the order of 10 DNA markers on 15q. Five laboratories performed a total of 2111 genotypes in 22 families consisting of 225 affected and 248 normal subjects. For each marker a mean of 98 meioses was informative. D15S48 and D15S1 were identified as the closest linked markers with 99% upper confidence intervals of 12% and 13% respectively. We have used the CRI-MAP program to construct the most likely order as: D15S24-D15S25-D15S1-MFS1-D15S48-D15S49+ ++-(D15S45/S51)-(D15S29/S38). Placement of D15S2 in relation to -D15S1-D15S48- cannot be determined with certainty. The genetic map of these markers extends 53.6 cM in males and 65.0 cM in females with a sex averaged map of 60.7 cM. The sex difference was statistically significant (p = 0.005). Linkage heterogeneity between 22 MFS1 families was documented (p = 0.009) necessitating the exclusion of one family from the analysis. However, comparison of the remaining 21 families for two point and multipoint lod scores showed no evidence for linkage heterogeneity of the MFS1 locus.

Chromosome Mapping↗
PubMed1991

Recurrent mutation at aa 792 in the LDL receptor gene in a French patient.

Many mutations in the low density lipoprotein receptor gene (LDLR) have been characterized at the molecular level in individuals with familial hypercholesterolemia. Most of the mutations that have been reported are large deletions or insertions in the gene, it being much more difficult to identify point mutations. In this study, 139 unrelated French familial hypercholesterolemia subjects were screened for the presence of three different previously described LDLR point mutations, employing the polymerase chain reaction and allele-specific oligonucleotide hybridization. Only one subject carried a point mutation at amino acid position 792, which substituted a Trp codon for a Stop codon. The same mutation has previously been described in a subject originating from Saudi Arabia. Haplotype analysis of LDLR associated with each mutation was performed. The haplotypes were totally different, suggesting that this mutation has occurred more than once.

Base Sequence↗
PubMed1991

Extended haplotypes and linkage disequilibrium between 11 markers at the APOA1-C3-A4 gene cluster on chromosome 11.

One hundred fifty-four unrelated French Caucasian subjects were typed for 11 RFLPs at or near the APOA1-C3-A4 gene cluster on the long arm of chromosome 11. All subjects belonged to families having lived in the Toulouse area (in the southwest of France) for over three generations. Allele frequencies for each RFLP were in agreement with previous studies in Caucasian populations for the APOA1/SstI marker. Pairwise linkage disequilibrium was determined. Among the 55 pairs studied, 30 are newly reported. Only three significant nonrandom associations were found: APOA1/MspI-3'APOC3/SstI, APOA1/MspI-3'APOA4/XbaI, and APOA4/DraI-APOA4/XbaI. Extended 11-marker haplotypes were constructed. Haplotype frequencies were estimated by the maximum-likelihood procedure and compared to expected frequencies calculated under the assumption of equilibrium. Among the 37 estimated haplotypes, seven containing at least four nonrandomly associated alleles showed markedly increased frequencies. These results, obtained in a geographically homogeneous population, confirm the existence of disequilibrium in the apolipoprotein cluster, but to a lower extent than previously reported in Caucasian populations, which were geographically more heterogeneous.

Apolipoprotein A-I↗
PubMed1990

Linkage analysis of five fibrillar collagen loci in a large French Marfan syndrome family.

Marfan syndrome consists of a group of dominantly inherited disorders of connective tissue with wide clinical variability. Using the candidate gene approach, we have attempted to map the gene defect in a large French Marfan syndrome family with no ocular manifestations. We performed linkage studies with polymorphic probes for five structural procollagen genes. The data obtained exclude linkage of Marfan syndrome to the two major fibrillar collagen (COL1A1, COL1A2, and COL2A1) genes. These results confirm previously published data obtained from smaller pedigrees. A small positive lod score (Z = 0.99, theta = 0.00) was obtained for the COL3A1-COL5A2 gene cluster located on chromosome 2.

Chromosome Mapping↗
PubMed1989

[Detection of deletions by the amplification of exons (multiplex PCR) in Duchenne muscular dystrophy].

The polymerase chain reaction is a new powerful method for in vitro cloning of specific regions of DNA. The use of the heat-stable DNA polymerase made the reaction amenable to automation. This method greatly facilitates the detection of mutations which are responsible for Duchenne muscular dystrophy, via DNA amplification of multiple deletions prone exons from the DMD gene.

Chromosome Deletion↗
PubMedDate not supplied

Coagulation/fibrinolysis balance in septic shock related to cytokines and clinical state.

This study explored the relationship between cytokines (TNF, IL-1, IL-6), coagulation and fibrinolytic factors in the early stage of sepsis syndrome and the relation between these factors with the severity of inflammatory illness as measured by the Simplified Acute Physiology Score (SAPS). Twenty-one normal controls were compared to 34 patients divided into three categories ranging from uncomplicated postoperative patients, to patients with severe infectious conditions including septic shock. A major hemostatic imbalance was demonstrated with particularly marked reduction in fibrinolytic activity [drop of antithrombin III (ATIII) and protein C with an increase of plasminogen activator inhibitor (PAI-1) levels] which were directly correlated with the severity of the inflammatory state. Both ATIII and PAI-1 levels were correlated with the levels of TNF and IL-6 and the severity of illness as measured by SAPS. We established an index, ATIII/PAI-1 antigen that is significantly different among the four groups (p < 0.001) and strongly correlated with the SAPS (p < 0.001). As PAI-1 could be secreted not only by TNF activating endothelial cells but also by hepatocytes activated by insulinemia, treatment of sepsis with cytokine-specific agents might be of limited effect.

Adult↗
PubMedDate not supplied

Diacerein reduces the level of cartilage chondrocyte DNA fragmentation and death in experimental dog osteoarthritic cartilage at the same time that it inhibits caspase-3 and inducible nitric oxide synthase.

OBJECTIVE: The primary objective of this study was to evaluate the ex vivo therapeutic efficacy of diacerein and its active metabolite, rhein, on osteoarthritic (OA) cartilage chondrocyte DNA fragmentation and death in the experimental canine model of OA. The study also aimed to explore the effect of the drug on the level of important factors involved in this phenomenon, i.e., caspase-3 and inducible nitric oxide synthase (iNOS). METHODS: OA knee cartilage was obtained from dogs that had received surgical sectioning of the anterior cruciate ligament (ACL) and were sacrificed 12 weeks after surgery. Cartilage explants were cultured in the presence or absence of therapeutic concentrations of diacerein (20 micrograms/ml) or rhein (20 micrograms/ml). Cartilage specimens were stained for TUNEL reaction and immunostained using specific antibodies for active caspase-3 and iNOS. Morphometric analyses were also performed. RESULTS: In OA cartilage specimens, a large number of chondrocytes in the superficial layers stained positive for TUNEL reaction. Treatment with therapeutic concentrations of diacerein (20 micrograms/ml) or rhein (20 micrograms/ml) significantly reduced the level of chondrocyte DNA fragmentation to about the same extent in both treatment groups (P < 0.006, P < 0.002, respectively). The levels of caspase-3 and iNOS in cartilage explants were also significantly decreased (caspase-3, diacerein P < 0.04; caspase-3, rhein P < 0.0003; and iNOS, rhein P < 0.009, respectively) when compared to the control group. CONCLUSIONS: This study shows that diacerein/rhein can effectively reduce the level of OA chondrocyte DNA fragmentation and death under the present experimental conditions. This effect is mediated by a decrease in the level of caspase-3 expression, which could possibly be related in part to the reduced level of iNOS and secondarily to NO production. These findings provide additional new information about the mechanisms of action of diacerein on the progression of OA.

Animals↗