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C Lefebvre

Publications and source records attributed to C Lefebvre.

At least 37 records · Page 2Linked to original sources
PubMed2000

The role of B-mode ultrasonography and electron beam computed tomography in evaluation of Takayasu's arteritis: a study of 43 patients.

OBJECTIVES: To evaluate the capacity of B-Mode ultrasonography (B-Mode US) and electron-beam computed tomography (EBCT) to detect arterial changes in Takayasu's arteritis. METHODS: EBCT angiography of the thoracoabdominal aorta and pulmonary artery, and B-mode US of large superficial arteries (common carotid, subclavian, and common femoral arteries) were performed prospectively in 43 consecutive patients with established Takayasu's arteritis. The arterial wall thickness was measured, and lumen changes (stenosis, aneurysm) were noted. RESULTS: The combined results of B-Mode US and EBCT examinations showed that every patient had at least one abnormality at the studied sites. The median score of abnormal sites was 7. The most frequent lesion was a characteristic long, homogeneous, circumferential thickening, visualized in 52% of examined sites and in all patients but one (98%). Stenosis was detected by US and by EBCT, respectively, in 44% and 32% of patients, and aneurysm in 0.4% and 68%. CONCLUSIONS: In Takayasu's arteritis, B-Mode US and EBCT was able to visualize the classical caliber abnormalities (stenosis, aneurysm) and, in contrast to angiography, to depict vessel wall thickening, a major pathologic feature of the disease. Both these safe techniques seem more useful than angiography to characterize and map the vascular lesions of Takayasu's arteritis.

Adolescent↗
PubMed1999

No evidence for germline PTEN mutations in families with breast and brain tumours.

Germline mutations of the PTEN gene are involved in Cowden disease, a genetic condition associated with an increased risk of breast cancer. Further somatic PTEN mutations have been found in glioblastomas and to a lesser extent in meningiomas. Therefore, PTEN germline mutations were searched for in a series of 20 unrelated women with breast cancer who also had a personal or familial breast-brain tumour history. Inclusion criteria were 1. family history of breast cancer; 2. absence of germline BRCA1 and p53 mutation; and 3. at least one case of brain tumour (glioblastoma, meningioma, or medulloblastoma) in either the index case or one of their first or second degree relatives. Any stigmata of Cowden disease was an exclusion criteria. Screening of the PTEN gene for point mutations or small rearrangements were performed using the denaturing gradient gel electrophoresis method on the 9 coding exons. No disease-associated mutation of the PTEN gene has been detected in our series. It is, thus, unlikely that PTEN is a significant BRCA predisposing locus. However, one might ask whether breast cancer cases resulting from germline PTEN mutation could occur without any mammary histological feature of Cowden disease.

Brain Neoplasms↗
PubMed1999

Electron beam CT features of the pulmonary artery in Takayasu's arteritis.

OBJECTIVE: Pulmonary artery involvement in Takayasu's arteritis is suggestive of the disease. Our aim was to use electron beam CT to study pulmonary artery changes in patients with Takayasu's arteritis. CONCLUSION: Diffuse wall thickening and dilatation or stenosis were significantly more frequent on CT in patients with Takayasu's arteritis than in the control subjects. Knowledge of these findings may be of value when assessing pulmonary artery involvement and thus may be helpful for the diagnosis of Takayasu's arteritis.

Adult↗
PubMed1999

Prediction of body composition of live and post-mortem red foxes.

A series of measurements (lengths, circumferences, skinfolds, masses and resistance) was taken on 29 red foxes (Vulpes vulpes) of both sexes before and after their death during the autumns of 1994 and 1995. Body composition of each carcass was determined by chemical analysis of homogenized samples of viscera, carcass and skin. Eight multiple regression models were then developed to predict body water, fat, protein, and mineral mass using body measurements as independent variables taken on live or dead animals. All final models were highly significant (P < 0.0001) and included three or four explanatory variables. Adjusted coefficients of determination varied between 0.95 for water mass and 0.81 for mineral mass. The models cover a wide range of conditions as percent body fat in the 29 samples varied between 1.1 and 28.4%. Our models can serve for management or research purposes with live or dead red foxes as they are quick, inexpensive and nondestructive.

Animals↗
PubMed1998

Sequence of a 131-kb region of 5q13.1 containing the spinal muscular atrophy candidate genes SMN and NAIP.

The spinal muscular atrophies (SMA), which are characterized by motor neuron loss and progressive paralysis, are among the most common autosomal recessive disorders. The SMA region of chromosome 5q13.1 is distinguished by variable amplification of genomic sequence incorporating a number of genes and pseudogenes. Recently, two SMA candidate genes mapping to this area were identified: survival motor neuron (SMN) and neuronal apoptosis inhibitory protein (NAIP). The telomeric copy of SMN (SMNtel) is deleted in over 95% of cases of SMA, with NAIP deletions primarily seen in type I SMA. We present here 131 kb of genomic sequence from 5q13.1 incorporating both NAIP and SMNtel in addition to revisions of the original NAIP cDNA sequence. The Alu-rich NAIP-SMNtel interval contains the microsatellite polymorphisms that are deleted in as many as 80% of type I SMA chromosomes, focusing attention on this region in the pathogenesis of type I SMA.

Amino Acid Sequence↗
PubMed1998

Expression of gamma-IFN responsive genes in scavenger receptor over-expressing monocytes is associated with xanthomatosis.

We have recently described an inherited over-expression of the macrophage scavenger receptor (SR) in blood monocytes from members of a kindred, only two of whom displayed extensive xanthomatosis. Using mRNA differential display we demonstrated abnormally high expression of the signal transducer and activator of transcription (STAT1alpha) in monocytes from the proband II-2. Expression of gamma-interferon inducible protein 10 (IP-10), a STAT1alpha-responsive gene and mediator of inflammatory response, was also abnormally expressed in the monocytes from II-2. Over-expression of both genes was restricted to monocytes from II-2 and was not observed in monocytes from the clinically unaffected family members, unlike that of SR. Gel retardation assays with THP-1 cell extracts identified gamma-IFN inducible DNA binding activity to three potential STATI DNA binding elements in the human IP-10 promoter region from nucleotides - 245 to - 188. Taken together these results suggest that gamma-interferon mediated cell activation is responsible for STAT1alpha-induced transcription of the IP-10 gene in THP-1 macrophages as well as in monocytes from II-2. Analysis of monocytes from familial hypercholesterolemic (FH) subjects, who frequently develop xanthomatosis, revealed a significant number of subjects with elevated STAT1alpha and IP-10 expression. Our data suggest that the inflammatory effects of gamma-IFN signaling could play a role in foam cell formation and xanthomatosis.

Adult↗
PubMed1997

Genomic characterization of the mouse inhibitor of apoptosis protein 1 and 2 genes.

Genomic and cDNA clones encoding mouse inhibitor of apoptosis protein 1 and 2 (Miap1 and Miap2) were isolated and characterized. The genes encoding the 602-amino-acid MIAP1 protein and the 612-amino-acid MIAP2 protein are contained within a 57-kb locus in a tandem head-to-tail arrangement. The Miap1 gene consists of nine exons spanning 24 kb, and the Miap2 gene consists of seven exons spanning 21 kb. Fluorescence in situ hybridization analysis mapped the locus to chromosome 9A2, which is syntenic with portions of the human 11q22-q23 region containing the human homologues HIAP1 and HIAP2. Sequencing of the complete Miap1 and Miap2 cDNAs revealed an unusually long 5' untranslated region in the Miap2 transcript, which may indicate nonscanning ribosomal initiation of translation.

Amino Acid Sequence↗
PubMed1997

Cost-effectiveness of preoperative examinations.

Preoperative medical evaluation is needed to assess individual patients risks of perioperative morbidity and mortality. The content of the preoperative examination remains the object of discussion. Although a well documented preoperative assessment of a patient's health status might allow to optimise his condition before surgery and to plan the most appropriate perioperative management, leading to an improvement of perioperative outcome as well as a reduction in costs, data to support this claim are still most often indirect. A large number of patients remain asymptomatic, with normal tests, which raises questions about the appropriateness to request a battery of tests on every candidate to surgery. Patients risks should be assessed mainly by history and physical examination, which might reduce drastically preoperative indication of laboratory tests: age, operation site, preoperative diseases and emergent surgery are important factors to consider. A risk estimate is presented, as well as recommendations for a preoperative health assessment, by categories of patients, following a screening pathway. Costs have been estimated in various alternatives. They have been evaluated to be above 2 billion BEF per year in Belgium for 563,485 surgical cases, and could most likely be reduced by about 60% in a near future.

Adult↗
PubMed1997

[Panorama of uropathies discovered during the prenatal period. 147 cases].

OBJECTIVES: The aim of this study was to establish the panorama of uropathies discovered during the antenatal period and to analyze the explorations performed. Pregnancy outcome and infant prognosis was also recorded. METHOD: Ultrasonographic imaging revealed dilatation in 62.5% of the cases, parenchymal anomalies in 26.3% and unilateral or bilateral agenesia in 11.2%. The percentage of abnormal karyotypes was 4.76% for all urorenal symptomatologies. These abnormal karyotypes corresponded to 10% of those performed in 17 fetuses, urine puncture was used in order to assess in utero renal function. There were 113 live births, 31 medically termined pregnancies and 3 spontaneous abortions. Among the 113 live infants, 12 died during the post-natal period. Thirty-two infants were considered to be normal and 69 had an urorenal malformation, including 2 infants with pre-end-stage renal failure at 4 and 3 years. CONCLUSION: It is uncommon to discover an urorenal malformation at prenatal ultrasonography. The main problem is antenatal management and evaluation of prognosis. Urine puncture and in utero derivation are discussed. When no other reliable factors affecting fetal prognosis are available, puncture of fetal urine provides useful information for management although the technique remains under debate.

Abortion, Therapeutic↗
PubMed1997

[Retinal occlusive vasculopathy and primary anti-phospholipid syndrome: when to evoke it?].

A severe case of retinal vascular occlusion in a 31 year old white female is reported. Its origin is attributed to the primary antiphospholipid syndrome. The diagnostic criteria and the treatment of the primary antiphospholipid syndrome are revised and discussed. When the etiology of a retinal vascular occlusion is not assessed by the initial work-up, especially if the initial presentation consists of a severe occlusive disease, antiphospholipid antibodies should be checked.

Adult↗
PubMed1996

Suppression of apoptosis in mammalian cells by NAIP and a related family of IAP genes.

Dysregulation of apoptosis can result in inappropriate suppression of cell death, as occurs in the development of some cancers, or in failure to control the extent of cell death, as is believed to occur in acquired immunodeficiency and certain neurodegenerative disorders, such as spinal muscular atrophy (SMA). Recently, we isolated a candidate gene, encoding neuronal apoptosis inhibitor protein (NAIP), for SMA. This gene is homologous to two baculovirus inhibitor of apoptosis proteins (Cp-IAP and Op-IAP) and is partly deleted in individuals with type I SMA. A second SMA candidate gene encoding survival motor neuron (SMN), which is contiguous with the NAIP locus on 5q13.1, was also reported. Here we demonstrate a NAIP-mediated inhibition of apoptosis induced by a variety of signals, and have identified three additional human complementary DNAs and a Drosophila melanogaster sequence that are also homologous to the baculovirus IAPs. The four open reading frames (ORFs) possess three baculoviral inhibition of apoptosis protein repeat (BIR) domains and a carboxy-terminal RING zinc-finger. The human iap genes have a distinct but overlapping pattern of expression in fetal and adult tissues. These proteins significantly increase the number of known apoptotic suppressors.

Adult↗
PubMed1996

Hypocalcaemia and chronic alcohol intoxication: transient hypoparathyroidism secondary to magnesium deficiency.

The authors report the observation of an alcoholic patient admitted for tetanic manifestations, in whom severe hypocalcaemia associated with hyperphosphatemia were suggestive of hypoparathyroidism. Administration of magnesium supplementation alone improved the clinical features and led to the correction of the calcium abnormalities. The mechanisms of hypomagnesemia in alcohol intoxication are reviewed as well as the links with hypocalcaemia.

Aged↗
PubMed1996

Response of oral mucosal cells to glass ionomer cements.

Although glass ionomer cements are generally considered to be tissue-compatible, it has been suggested that unreacted components or setting reaction by-products can affect cell metabolism. The current study examined the effects of constituents leached out of three glass ionomer cements on growth and metabolism of oral epithelial cells. Aseptically prepared discs of Ketac-Cem Radiopaque (KCR), Ketac-Cem Maxicap (KCM) and Fuji I were incubated in Dulbecco's medium for 10 d, with daily medium changes. Cultures of hamster cheek pouch (HCP) cells, a line of hamster buccal pouch epithelial cells, were incubated in control or eluate-containing media for 24 h. Viable cell numbers were determined by the colorimetric MTS assay, and DNA and RNA syntheses were assessed using [3H]thymidine and [3H]uridine incorporation, respectively. Responses to materials were determined by comparison of cell numbers and radioisotope incorporation (counts per minute (cpm) per 1000 cells). Results were analysed by ANOVA and Duncan's multiple range test, then converted to percent control for comparison. The eluates of all three materials from the first 24 h of soaking inhibited HCP cell growth. The number of cells in cultures exposed to Fuji were 88% of control cultures, while those exposed to KCR and KCM were 58% and 59% of control, respectively. The difference between Fuji-exposed and control cultures was significant (P < 0.05). The two Ketac cements were different from Fuji-exposed and control cultures (P < 0.05) but not from each other. All of the materials caused significant increases in labelling of DNA compared to control cultures (P < 0.05) when calculated on a per cell basis, but the materials did not differ from each other. Both Ketac cements also significantly stimulated labelling of RNA per cell compared to control cultures (P < 0.05). All effects of the material decreased over time. Results suggest that leachable components of the materials may affect the rate of progression of HCP cells through the cell cycle, rather than overt toxicity that results in cell death.

Animals↗