PubMed Health⌕ Search

Biomedical subjects

M Loriaux

Publications and source records attributed to M Loriaux.

8 recordsLinked to original sources

Demonstration of Philadelphia chromosome negative abnormal clones in patients with chronic myelogenous leukemia during major cytogenetic responses induced by imatinib mesylate.

Imatinib mesylate, an Abl-specific kinase inhibitor, produces sustained complete hematologic responses (CHR) and major cytogenetic responses (MCR) in chronic myeloid leukemia (CML) patients, but long-term outcomes in these patients are not yet known. This article reports the identification of clonal abnormalities in cells lacking detectable Philadelphia (Ph) chromosome/BCR-ABL rearrangements from seven patients with chronic- or accelerated-phase CML, who were treated with imatinib. All seven patients were refractory or intolerant to interferon therapy. Six of seven patients demonstrated MCR and one patient, who had a cryptic translocation, achieved low-level positivity (2.5%) for BCR-ABL by fluorescence in situ hybridization. The median duration of imatinib treatment before the identification of cytogenetic abnormalities in BCR-ABL-negative cells was 13 months. The most common cytogenetic abnormality was trisomy 8, documented in three patients. All patients had varying degrees of dysplastic morphologic abnormalities. One patient exhibited increased numbers of marrow blasts, yet consistently demonstrated no Ph-positive metaphases and the absence of morphologic features of CML. The presence of clonal abnormalities in Ph-negative cells of imatinib-treated CML patients with MCR and CHR highlights the importance of routine metaphase cytogenetic testing and long-term follow-up of all imatinib-treated patients.

Adult↗

Bifurcated drum occluder endograft for treatment of abdominal aortic aneurysm: an experimental study in dogs.

PURPOSE: To evaluate a new, low profile, home-made, bifurcated drum occluder endograft (BDOEG), designed for percutaneous, transcatheter treatment of abdominal aortic aneurysm (AAA). MATERIALS AND METHODS: AAA was created in 10 dogs with over-dilated Palmaz stents. To prevent back filling, the lumbar arteries, inferior mesenteric artery, and common internal iliac arteries were embolized. The BDOEG was constructed of a drum occluder device and two PTFE endografts. The drum device consisted of a modified Z stent with Dacron stretched across and held within the ends of the stent, each with two 8 x 6-mm slits through which PTFE endografts were delivered. The PTFE endografts were 8 mm in diameter and 9.5 cm in length. Preloaded, the BDOEG was delivered through a 10-F sheath from both femoral arteries in a three-step procedure. All 10 animals were treated with BDOEG. Aortography was performed immediately, 6 weeks, and 12 weeks after stent-graft placement. Five animals were killed at 6 weeks and five were killed at 3 months. Gross and histologic evaluation was performed. RESULTS: The infrarenal aortic diameters and both external iliac arteries ranged from 8.0 mm to 10.3 mm (mean, 9.4 mm +/- 0.6) and from 5.2 mm to 6.8 mm (mean, 5.8 mm +/- 0.5), respectively. Creation of the AAA was successful in all 10 dogs. AAA diameters ranged from 13.7 mm to 15.9 mm (mean, 14.9 mm +/- 0.7). Complete exclusion of the AAA was achieved immediately after BDOEG placement and aneurysms remained excluded without perigraft leak to the time of killing in all 10 animals. There was a high incidence of aortoiliac limb occlusion. Occlusion of 12 aortoiliac limbs (60%) caused by intimal hyperplasia at the distal end of the endografts in iliac arteries developed in nine animals (90%). In six animals (60%), one limb occluded and, in three animals (30%), there was occlusion of both limbs. CONCLUSION: This study suggests a new approach for treatment of AAA. BDOEG use reduces sheath size for endograft delivery and may eliminate the need for a surgical cut down on femoral arteries. Tapering of the iliac ends of endografts to the size of the artery will be needed to prevent distal intimal hyperplasia.

Animals↗

The square stent-based large vessel occluder: an experimental pilot study.

PURPOSE: The purpose of this study is in vitro and in vivo experimental evaluation of a square stent-based vascular occlusion device for large vessels. MATERIALS AND METHODS: Square stent-based large vessel occluders (LVO) 5 mm-50 mm in size were constructed from stainless-steel square stents covered by porcine small intestine submucosa (SIS). The LVOs with two back-side barbs were delivered through a guiding catheter. The LVOs with two back-side barbs and two frontal barbs were front-loaded and delivered coaxially. A pusher with a retention mechanism at its end was used for deployment. In vitro testing for competency was performed with use of a flow model with pressure increases. In an experimental pilot study in seven pigs and five dogs, 16 LVOs were placed into the aorta (n = 4), common iliac artery (n = 2), pulmonary artery (n = 4), and medial sacral artery (n = 6). Four animals received two LVOs in different locations. Angiography was performed before and after placement of each LVO. Animals were followed for as long as 3 months with use of angiography and were then killed for gross and histologic evaluation. RESULTS: In vitro LVOs with two and four barbs were easily collapsed and pushed through or front-loaded into guiding catheters (6-F for a 5-mm occluder, 10-F for a 50-mm occluder). A 20-mm LVO adapted to tubular structures 10-15 mm in diameter, forming polygons 17-18.5 mm in length. In the flow model, LVOs endured pressure increases to 300 mm Hg. In vivo, the LVOs self-expanded and adapted to the vessel without migration in all cases. The locking pusher allowed precise LVO placement and engagement of its barbs into the vessel wall before complete deployment, preventing dislodgment by blood flow. Complete arterial occlusion occurred within 10-20 minutes and arteries remained occluded until the animal was killed in all cases. After 2 months, histologic evaluation revealed replacement of SIS by host tissue and its remodeling with variable fibrocytes, fibroblasts, and some inflammatory cells. Complete endothelialization was seen on both sides of the LVO. CONCLUSION: The SIS LVO is effective and reliable for acute and chronic occlusion in a high flow model in an experimental animal.

Angiography↗

[The consequences of the demographic revolution and of the aging of society: restructuring the age groups and modifying intergenerational relations].

The consequences of demographic aging in developed societies are examined. The author notes that "demographic aging has intensified over the last decades, bringing with it a significant modification in relationships between age groups and the sexes.... These changes in demographic structures bring with them the reorganization in intergenerational relations, the most spectacular instance of which...[is] the coexistence at the same time and in the same place of four or five generations of direct descendants." The author develops the hypothesis that a new attitude toward old age is needed in which "the social status of the elderly must be reinstated, and everything must be brought into play to encourage the integration of different age groups and intergenerational solidarity, so as to arrive in the best possible conditions at what [can be termed] the 'era of old age'...which will accompany the coming of the post-industrial society with its orientation toward the mass production of leisure and of services." (SUMMARY IN ENG AND SPA)

Age Distribution↗

Polyurethane-coated Dacron-covered stent-grafts for TIPS: results in swine.

PURPOSE: To evaluate shunt patency after placing a new polyurethane-coated Dacron-covered spiral Z stent-graft to create a transjugular intrahepatic portosystemic shunt (TIPS). METHODS: TIPS stent-grafts were placed in six young swine, using polyurethane-coated, Dacron-covered spiral Z stent-grafts. Animals were followed weekly by transhepatic portal venography until shunt occlusion or up to 6 weeks, then were sacrificed for gross and histologic evaluation. RESULTS: Five of six TIPS stent-grafts were found to be occluded by 3 weeks and none were patent at 6 weeks. Histologic evaluation demonstrated a marked foreign body reaction with superimposed thrombosis occluding the graft lumen. CONCLUSION: Polyurethane-coated Dacron-covered stent-grafts do not improve TIPS patency.

Animals↗