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D Paris

Publications and source records attributed to D Paris.

At least 37 records · Page 2Linked to original sources
PubMed1998

Friedreich's ataxia presenting as adult-onset spastic paraparesis.

We have studied a man with an atypical form of Friedreich's ataxia (FRDA), who presented at age 26 years with a 2-year history of unsteadiness and clumsiness. The predominant feature of his initial neurological examination was a spastic paraparesis, along with a mild distal weakness and hyperreflexia of the upper limbs. He also displayed limb ataxia. Frataxin GAA repeat sizes were 1,040/690. This unusual FRDA presentation is not dissimilar to that of Acadian spastic ataxia.

Adult↗
PubMed1998

Sperm DNA analysis in a Friedreich ataxia premutation carrier suggests both meiotic and mitotic expansion in the FRDA gene.

Friedreich ataxia is usually caused by an expansion of a GAA trinucleotide repeat in intron 1 of the FRDA gene. Occasionally, a fully expanded allele has been found to arise from a premutation of 100 or less triplet repeats. We have examined the sperm DNA of a premutation carrier. This man's leucocyte DNA showed one normal allele and one allele of approximately 100 repeats. His sperm showed an expanded allele in a tight range centering on a size of approximately 320 trinucleotide repeats. His affected son has repeat sizes of 1040 and 540. These data suggest that expansion occurs in two stages, the first during meiosis followed by a second mitotic expansion. We also show that in all informative carrier father to affected child transmissions, with the notable exception of the premutation carrier, the expansion size decreases.

Adaptor Proteins, Signal Transducing↗
PubMed1998

A comparison of role expectations and communication styles between transplant coordinators and transplant staff nurses.

The role of the transplant coordinator is multifaceted and demanding, requiring advanced clinical skills in addition to patient management responsibilities. Although much is known about the clinical skills of these coordinators, there is virtually no information available about their management abilities. A comparison of the beliefs of transplant coordinators and transplant staff nurses confirms that the coordinators have the role expectations and communication styles to allow them to function effectively in managing patient care as well as in working with physicians and other health professionals.

Adult↗
PubMed1997

Premature thymic involution, observed at the ultrastructural level, in two lineages of human-SOD-1 transgenic mice.

The human Cu/Zn superoxide dismutase (hSOD-1) gene, catalyses the dismutation of O2 to H2O2 and O2. It is located on chromosome 21 in q22.1 and is overexpressed in Down's syndrome (DS) patients. These patients present various abnormalities including mental retardation, congenital heart disease, immunological deficits and premature aging. In order to explore the potential role of SOD-1 overexpression in DS, we have generated two lineages of transgenic mice for the hSOD-1 gene and studied, at the ultrastructural level, the effect of hSOD-1 overexpression on the thymic microenvironment. Modification of the cellular architecture and morphology associated with a lipidic invasion, signs of a premature involution of the thymus, were observed in both lineages. A rupture of the filamentous network in the extracellular and probably also in the intracellular matrix was first observed. These results correlate the thymic alterations visualized in light microscopy, on the thymus from DS patients, and raise the question of the relationship between the SOD-1 overexpression and the different morphological alterations associated with the premature thymic involution observed in SOD-1 transgenic mice. They suggest that thymic and immunological impairments present in DS patients may be related to the SOD-1 gene dosage effect.

Aging↗
PubMed1996

Rapid fluorescence in situ hybridization on interphasic nuclei to discriminate between homozygous and heterozygous transgenic mice.

Homozygous and heterozygous transgenic mice of the Tg152 line overexpressing the human copper/zinc superoxide dismutase (hSOD-1) were rapidly differentiated by fluorescence in situ hybridization (FISH) using interphase lymphocyte nuclei. We have devised a simple and fast method for preparing interphase nuclei with very small quantities of whole mouse blood, avoiding several steps of the classical FISH technique. Lymphocyte separation and cell culture were not required. This technique provides an excellent tool for the unambiguous detection of homozygous and heterozygous transgenic mice in a litter. It can be used to check young animals since 2 microliters of whole blood is sufficient. We also show that in this transgenic line numerous copies of the hSOD-1 transgene are integrated at a single autosomal locus, in tandem head-to-tail organization.

Animals↗
PubMed1996

Acute arterial obliteration: a new feature of the POEMS syndrome?

The POEMS (polyneuropathy, organomegaly, endocrinopathy, monoclonal gammapathy, and skin changes) syndrome is a rare variant of plasma cell dyscrasia with multisystemic manifestations. We present 4 cases with arterial symptoms typical of acute arterial obliteration (AAO) and review 9 similar cases in the literature. The clinical course of AAO was unusual and particularly severe when affecting the lower limbs; recurrent events required amputations. As demonstrated by angiographic and histologic studies, thrombotic and atheromatous lesions were the main pathologic features of AAO. Atherosclerotic risk factors were absent or moderate in 3 of our cases, and no cause of thrombosis other than the POEMS syndrome was found. A high production of cytokines was found in all cases, with elevated serum levels of interleukin-1 beta (9/9 samples), interleukin-6 (7/9 samples), and tumor necrosis factor-alpha (6/9 samples). We suggest that arterial manifestations should be added to the spectrum of manifestations of the POEMS syndrome. Cytokines may mediate the POEMS syndrome-associated AAO, as previously proposed for the other systemic manifestations of this disorder.

Acute Disease↗
PubMed1996

Transgenic mice overexpressing the human Cu/Zn-SOD gene: ultrastructural studies of a premature thymic involution model of Down's syndrome (trisomy 21).

It has been suggested that the overexpression of copper-zinc superoxide dismutase (SOD-1) in Down's syndrome (DS) patients may be involved in expression of some of the phenotypic characteristics observed in these patients. To explore the possible role of SOD-1 overexpression in the premature thymic involution and immunologic disorders observed in DS patients, transgenic mice overexpressing the human SOD-1 gene have been generated and their thymuses have been studied at the ultrastructural level. Our observations show premature involution of the thymus in SOD-1 transgenic mice, with a strong modification of the thymic microenvironment starting at approximately 3-4 months of age. The thymic microenvironment in 7-month-old transgenic mice is similar to that observed in 20-month-old control mice. We suggest that these results are consistent with the role of SOD-1 overexpression in the early thymic involution observed in DS patients. These transgenic mice provide an interesting model to investigate the deleterious effect of increased dosage of some chromosome 21 genes such as SOD-1 in the pathogenesis of DS.

Animals↗
PubMed1996

[Long-term results of active-passive ligament repair of the external lateral ligament of the ankle].

We reviewed 95 ankles at an average of 9 years after an "activo-passive" operation performed for chronic lateral instability. All the patients had suffered recurrent ankle sprain or instability, with pain in 67 patients. Ten ankles showed a subtalar injury at operation. Degenerative changes were noted in 11 ankle joints. On review, 81 ankles (85%) were stable. The 14 cases with persistent instability had developed the problem one to five years after operation. Two cases presented with limitation in mobility. Osteoarthritis, found in 15 ankles, was severe in only two, and had been present on preoperative films. We found no correlation between functional results (talar tilt, anterior-drawer test) and radiological evaluation. The "activo-passive" operation provides long-term stabilization with preservation of the ankle and of subtalar mobility without severe osteoarthritis.

Adolescent↗
PubMed1995

Genomic organization of the human cystathionine beta-synthase gene: evidence for various cDNAs.

A CBS cDNA isolated from an adult liver cDNA library was cloned and sequenced. The 5' untranslated region (5'-UTR) contains a sequence which is only partially common (88nt) with that previously published (3). It is expressed as a 2.5kb species mostly in liver and pancreas and faintly in brain, heart, kidney and lung and as a 3.7 kb in pancreas and liver. The human cystathionine beta-synthase gene (CBS) was isolated from a cosmid genomic library and its structure was determined. The CBS gene is at least 23 kb long and is composed of 17 exons. The organization of the human gene is different from that of the rat especially in the 5'-UTR. In the rat gene the ATG is present in exon 1, conversely in the human gene first the ATG is present in exon 3 and second the 5'-UTR contains two different exons 1 (E1a and E1b) linked with exon 2.

Adult↗
PubMed1995

Synthesis, structure-activity relationships, and pharmacological evaluation of pyrrolo[3,2,1-ij]quinoline derivatives: potent histamine and platelet activating factor antagonism and 5-lipoxygenase inhibitory properties. Potential therapeutic application in asthma.

A series of pyrrolo[3,2,1-ij]quinoline derivatives was synthesized and evaluated for their in vitro and in vivo activities against histamine, platelet activating factor (PAF), and leukotrienes which are recognized to be of importance in asthma. The structure-activity relationship studies have shown that the optimum moiety on the 1-position of the pyrroloquinoline nucleus is a 2-[4-(4-methyl-2-pyridinyl)-1-piperazinyl]ethyl chain in conjunction with a methyl group on the 2-position for potent antagonism of both histamine and PAF. The introduction of substituents on the 8- and 4-positions was also investigated in order to increase the potency of 5-lipoxygenase inhibition while retaining or improving the activities against histamine and PAF. This series is exemplified by 4-n-butyl-5,6-dihydro-8-hydroxy-2-methyl-1- [2-[4-(4-methyl-2-pyridinyl)-1-piperazinyl]ethyl]-4H-pyrrolo[3,2,1- ij]quinoline (24, KC 11404) which was found to be active against all three of the selected mediators. Compound 24 was found to be orally active in guinea pig models against the histaminic phase of antigen-induced bronchospasm and PAF-induced bronchoconstriction (ED50 = 1.9 and 2.1 mumol/kg, respectively). When tested against the leukotriene-dependent phase of the antigen-induced bronchoconstriction, compound 24 showed the same potency as zileuton.

Animals↗
PubMed1995

Ballistocraft: a novel facility for microgravity research.

One of ESA's aims is to provide the microgravity research community with various microgravity exposure facilities. Those facilities include drop towers, sounding rockets, and parabolic flights on board aircraft, in addition to orbital spacecraft. Microgravity flights are usually achieved using large aircraft like the French 'Caravelle' that offer a large payload volume and where a person can be present to perform the experiments and to participate as a human test-subject. However, the microgravity community is also very interested in a flexible, complementary facility that would allow frequent and repetitive exposure to microgravity for a laboratory-type of payload. ESA has therefore undertaken a study of the potential of using a 'ballistocraft', a small unmanned aircraft, to provide a low-cost facility for short-duration (30-40 seconds) microgravity experimentation. Fokker Space & Systems performed the study under an ESA contract, supported by Dutch national funding. To assess the ballistocraft, a simple breadboard of the facility was built and flight tests were performed. The ability of the on-board controller to achieve automated parabolic flights was demonstrated, and the performance of the controller in one-g level flights, and in flights with both zero-g and partial-g setpoints, was evaluated. The partial-g flights are a unique and valuable feature of the facility.

Aircraft↗
PubMed1994

The factor analytic structure of seven physical CHD risk factors: a replication study.

An attempt was made to replicate the results of an earlier confirmatory factor analysis of the seven traditionally employed physical risk factors for CHD. As with the first investigation, a two-factor solution was confirmed; only family history loaded on factor 1; the remaining six risk variables (smoking, serum cholesterol, blood pressure, diet, exercise, and weight control) comprised factor 2. These findings may reflect a broad personality trait, i.e., generalized lack of self-control, which could underlie much CHD risk not associated with a family history of heart disease. Implications are drawn for research and practice in the areas of cardiac rehab and prevention.

Adult↗
PubMed1994

Abnormal coronary flow velocity pattern in patients with left ventricular hypertrophy, angina pectoris, and normal coronary arteries: a transesophageal Doppler echocardiographic study.

Previous invasive studies have suggested that coronary flow reserve is impaired in patients with left ventricular hypertrophy (LVH) and symptoms of ischemia. We tested whether transesophageal Doppler, a semiinvasive technique, can detect altered characteristics of baseline coronary blood flow velocity in such patients. Thirty patients with LVH (hypertrophic cardiomyopathy in 4, aortic stenosis in 17, hypertension in 9) were studied. Fourteen patients had asymptomatic LVH. Sixteen patients had clinical symptoms of ischemia with angiographically normal epicardial coronary arteries. Ten subjects with no cardiovascular disease were studied as a control group. Peak diastolic and systolic coronary flow velocities were recorded in the proximal part of the left anterior descending artery (LAD) with the use of pulsed Doppler guided by color flow imaging. Patients with symptomatic LVH had higher diastolic peak coronary flow velocity (81 +/- 10 cm/sec, p = 0.0001) compared with normal subjects (41 +/- 8 cm/sec) and patients with asymptomatic LVH (44 +/- 8 cm/sec). In patients with asymptomatic LVH the diastolic coronary flow velocity/indexed ventricular mass ratio was lower (0.28 +/- 0.09 cm/gm/m2, p = 0.0001) compared with symptomatic patients (0.52 +/- 0.12 cm/gm/m2) and compared with controls (0.47 +/- 0.16 cm/gm/m2). Patients with symptomatic LVH but no aortic stenosis also had higher peak systolic coronary flow velocity (38 +/- 9 cm/sec) compared with the other groups (p = 0.0001). In the group of patients with aortic stenosis a significant inverse linear relation was found between peak systolic coronary flow velocity and peak pressure gradient (r = -0.60, p 0.01). In conclusion, patients with symptomatic LVH have abnormally high baseline coronary flow velocities resulting in magnified intimal shear stress. Because flow velocity equals flow/vessel cross-sectional area, it is suggested that high coronary flow velocities in patients with symptomatic LVH result from both augmented coronary flow and failure of the vessel to enlarge commensurately with the increase in LV mass (relative functional stenosis). In patients with aortic stenosis, peak systolic coronary flow velocity appears to be influenced by transvalvular pressure drop.

Adult↗
PubMed1992

[Percutaneous aortic valvuloplasty. Long-term outcome apropos of 85 patients with successful dilatation].

The outcome at 2, 6, 12, 18 and 24 months in terms of clinical status and Doppler echocardiographic parameters of 85 patients successfully dilated out of 116 patients undergoing percutaneous aortic valvuloplasty is reported. The objectives were to determine the survival rate, degree of clinical remission, the restenosis rate and its predictive factors. The 31 patients considered to be primary failures were excluded from the study. The global survival rates were 90 +/- 2% at 2 months, 84 +/- 4% at 6 months, 78 +/- 5% at 12 months, 69 +/- 6% at 18 months and 60 +/- 8% at 2 years. Patients in clinical remission and with clinical relapse were compared at the 6th month: relapse was significantly, related to prevalvuloplathy, low cardiac output (p = 0.05), low ejection fraction (p less than 0.03) and low fractional shortening (p less than 0.01), but the clinical relapse was independent of aortic valve surface area before and dilatation. In the relapse group, 14 patients (12%) were operated without complications in the first month of follow up, 6 patients underwent repeat valvuloplasty with 4 immediate failures and 2 improvements. The other patients were treated medically. The restenosis rate (loss of greater than 50% of initial gain in surface area or return of pre-valvuloplasty maximal pressure gradient +/- 25%) increased up to the 12th month in both groups (remission and relapse) and reached 78% at 12 +/- 3 months and seemed more pronounced in the less severe aortic stenosis. The incidence of restenosis was independent of gain in surface area after valvuloplasty.(ABSTRACT TRUNCATED AT 250 WORDS)

Actuarial Analysis↗
PubMed1989

[Aortic valvuloplasty in the elderly. Immediate and medium-term results].

Between January 86 and February 88 we attempted percutaneous aortic valvuloplasty in 100 patients. 68 patients could be dilated with hemodynamic success: the aortic valve area increased from 0.52 +/- 0.17 cm2 to 0.78 +/- 0.27 cm2 (p less than 0.001). Cardiac output did not change significantly (4 +/- 1.1 l/mn). In the remaining 32 patients: 8 patients (8%) died in hospital and the morbidity rate was 11%: arterial injury (9), stroke (1) and major cardiac event (1). Sixty patients regarded as initial success were followed for 6 months: 3 patients (5%) died without cardiac events, functional improvement persisted in 41 patients (68%) and clinical failure was observed in 16 patients (27%): 4 patients died and in the remaining 12 patients, the recurrence of symptoms required medical treatment (5), surgery (5) or repeat percutaneous valvuloplasty (2). Echo-Doppler maximum aortic valve gradient was significantly less in improved patients (55 +/- 21 mmHg) than in deteriorated patients (78 +/- 36 mmHg) (p less than 0.02). One year after valvuloplasty: actuarial survival was 74 +/- 6%, clinical improvement was 53 +/- 7% and clinical recurrence was 41 +/- 7%. Thus percutaneous aortic valvuloplasty may be proposed only to non surgical patients.

Aged↗