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L Maillard

Publications and source records attributed to L Maillard.

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

[Comparison of coronary angiography by the left radial and right femoral approach with 4 French catheters].

The radial arterial approach has been shown to be valuable for coronary angioplasty. The aim of this study was to evaluate the use of the left radial and right femoral approaches for diagnostic coronary angiography. The authors performed a prospective non-randomised series of consecutive diagnostic coronary angiogrammes with small calibre (4 french) catheters by the left radial (100 patients) and right femoral (100 patients) arteries. The feasibility, results and complications were compared. The study showed that diagnostic coronary angiography with 4 F catheters is feasible with a high success rate, both from the left radial (99%) and right femoral (100%) approaches (NS). The duration of the procedure tends to be longer when the radial approach is used (19.2 +/- 1.3 min) than by the femoral artery (16.3 +/- 1.1 min) (p = 0.06). The duration of irradiation is longer with the radial approach (6.7 +/- 1.2 vs 4.9 +/- 0.9 min) (p = 0.0001). Local complications are minor by either approach (N = 5 vs N = 6 patients; p = NS), and there were no major complications. The tolerance of the procedure was not as good when the radial artery was used (N = 5) compared with the femoral artery (N = 1 patient) because of arterial spasm when the catheters were changed. The authors conclude that the left radial and right femoral arteries can be used routinely for diagnostic coronary angiography with small catheters (4 French). The left radial approach allows immediate mobilisation of the patient but the duration of the procedure and the exposure to irradiation are longer.

Aged↗
PubMed2000

[Ventricular late potentials in myocardial infarction: comparison of thrombolysis, primary angioplasty, and conventional treatment].

OBJECTIVES: The aim of this study was to compare the prevalence of ventricular late potentials (VLP) during the acute phase of myocardial infarction (MI) depending on the treatment used. METHODS AND RESULTS: This retrospective study was carried out over the period January 1992 to December 1997, and involved 238 patients admitted for primary MI and treated less than six hours after the onset of symptoms by intravenous thrombolysis (rt-PA, n = 83) or primary angioplasty (ATCI, n = 82) and in those cases treated over six hours after the onset of symptoms by standard treatment (heparin, n = 73). Rt-PA perfusion was considered to be effective when the three following criteria were simultaneously present: i) pain sedation; ii) regression of the ST dysfunction > 50%; iii) creatine phosphokinase (CPK) peak before the 16th hour. Treatment success for angioplasty (ATCI+) was confirmed by a TIMI 3 (Thrombolysis in Myocardial Infarction) score for MI arterial perfusion, with residual stenosis of the MI artery of < 50%. Ventricular late potentials (VLP) were investigated between day six and 14, and considered to be present when two of the following criteria were met: total duration of filtered QRS, i.e., QRSd > 114 ms; signal amplitude in the 49 last ms of filtered QRS, i.e., RMS40 < 20 mV, duration of the terminal part of filtered QRS that was below 40 mV, i.e., LAS40 > 38 ms (40 Hz). VLP prevalence was as follows: 25% (rt-PA group), 345 (ATCI group), and 33% (standard treatment) respectively (P = NS). In the thrombolysis with reperfusion subgroup (n = 54/83, 65%), VLP incidence was 18.5% (n = 10/54) versus 35.5% (n = 27/76) in the subgroup ACTI+ (n = 76/82, 93%) (P = 0.03). CONCLUSIONS: The prevalence of VLP appears to be significantly decreased in the the case of thrombolysis with reperfusion compared to that observed in the ATCI+ group. One of the possible explanations for this abnormally high prevalence in the angioplasty group could be a dysfunction involving reocclusion after initially successful myocardial reperfusion therapy.

Action Potentials↗
PubMed1999

Early cell loss after angioplasty results in a disproportionate decrease in percutaneous gene transfer to the vessel wall.

Acute cell loss has been documented following angioplasty of normal rat and rabbit arteries. Here we analyzed the effects of balloon injury intensity on early cellular loss in single- and double-injury models and how it influences the efficiency of percutaneous gene delivery to the vessel wall. Rabbits underwent bilateral iliac angioplasties (n = 52) with 2.5-mm (balloon-to-artery [B/A] ratio, 1.08 to 1.13) and 3.0-mm (B/A ratio, 1.29 to 1.34) balloons. In the single-injury model, the 3.0-mm balloon induced a 61% reduction in medial cellularity at 3 days postinjury (p < 0.001) while the 2.5-mm balloon did not produce significant cell loss. In the double-injury model, the effects were more pronounced, with 35% (p < 0.01) and 91% (p < 0.001) reductions in medial cellularity at 3 days with the 2.5- and 3.0-mm balloons, respectively, but neointimal cellularity was decreased only with the 3.0-mm balloon (37% reduction, p = 0.025). Adenovirus-mediated beta-galactosidase gene delivery with a channel balloon (n = 24) revealed that larger balloon-to-artery ratios decreased both absolute levels and relative frequencies of transgene expression in the vessel wall. In the single-injury model, gene transfer efficiency was 4.2+/-1.1 and 1.3+/-0.25% (p < 0.05) for the small and large balloons, respectively. In the double-injury model, gene transfer efficiency was 6.6+/-1.6 and 2.3+/-0.8% (p < 0.05) in the neointima and 4.1+/-1.2 and 2.6+/-1.2% (p = NS) in the media for the small and large balloon, respectively. We conclude that early cell loss is dependent on the intensity of the injury in both single- and double-injury models of balloon angioplasty, with greater frequencies of cell loss occurring in the media than in the neointima. In both models, larger balloon-to-artery ratios result in disproportionate reductions in percutaneous adenovirus-mediated gene delivery.

Adenoviridae↗
PubMed1999

[Balloon angioplasty].

Balloon angioplasty of the coronary arteries is about 20 years old and has become the main technique of myocardial revascularisation. It is performed under local anaesthetic by arterial puncture and some centres are already performing the procedures on an ambulatory basis. Optimally, the procedure should be performed in a well-equipped catheter laboratory with trained operators and experienced personnel. The most impressive results are obtained in single vessel disease. However, double and triple vessel disease may also be treated, especially in elderly, frail patients, in cases of high surgical risk or with a previous history of coronary bypass surgery. Balloon angioplasty has an important role in the treatment of acute myocardial infarction, either as an alternative or as a complement to thrombolytic therapy. The major limitations of this technique, in the absence of stenting, are the failure to pass chronic lesions, the occurrence of major complications in about 1% of cases, of acute occlusion in about 5% of cases, and, finally, of restenosis estimated between 30 and 50%, depending on the publication. In the general population, the success rate is over 95% with an immediate return to normal life and the possibility of repeating an angioplasty in cases of restenosis. Coronary stents are a major technical adjuvant to balloon angioplasty and the indications of their implantation have exceeded 50% of procedures in recent years.

Adult↗
PubMed1999

[Pre-capillary pulmonary hypertension complicating CREST syndrome. Apropos of a case].

Pre-capillary pulmonary hypertension was the presenting sign of a CREST syndrome in a 65 year old woman. The diagnosis of this form of scleroderma is based on the association of a number of features (calcinosis, Raynaud's phenomenon, oesophageal dyskinesia, sclerodactylia and telangectasia). Scleroderma is the systemic disease which is usually complicated by pre-capillary pulmonary hypertension. This complication is observed in about 13% of CREST syndromes, but very rarely as severe pre-capillary pulmonary hypertension. The diagnosis of pre-capillary pulmonary hypertension carries a poor prognosis with a 2 year survival rate of about 40%. Treatment is usually with calcium inhibitors but with no effect on prognosis. The use of prostacycline and its analogue, iloprost, is an interesting therapeutic strategy, currently under evaluation. Cardiopulmonary transplantation is the only treatment of very severe forms, despite the progressive character of the condition. All cases of pre-capillary pulmonary hypertension require complete aetiological investigation to exclude a systemic disease, especially a scleroderma and, above all, a CREST syndrome.

Aged↗
PubMed1998

Effects of poloxamer 407 on transfection time and percutaneous adenovirus-mediated gene transfer in native and stented vessels.

UNLABELLED: Reduction in transfection time and the ability to perform gene transfer in conjunction with endovascular stent implantation constitute two important challenges for percutaneous adenovirus-mediated gene transfer to vessel walls. Studies have suggested that the use of biocompatible polyol poloxamer 407 could be useful. We first evaluated the use of poloxamer 407 for percutaneous gene transfer in nonstented rabbit iliac arteries. A 200-microl mixture of Ad-RSVbetagal or Ad-CMVLuc in either phosphate-buffered saline (PBS) or 20% poloxamer was delivered. After 3 days, gene transfection was evaluated by X-Gal staining or measurement of luciferase activity. Poloxamer use resulted in a 3- to 15-fold increase in the percentage of transfected cells (X-Gal, p = 0.001) and a 16-fold increase in protein product (luciferase activity, p = 0.03), and allowed a decrease in transfection time from 30 to 5 min with minimal reduction in transfection efficiency. We then evaluated the feasibility of percutaneous gene transfer, using Ad-RSVbetagal diluted in pure PBS or 20% poloxamer, in conjunction with stent implantation. Gene delivery was performed either immediately before (pre-) or after (post-) stent implantation. When adenoviruses were diluted in PBS, gene transfer had a low efficiency (prestent, 0.3%; poststent, 0.2%; NS). With poloxamer, the efficacy was much higher (p = 0.0001) and similar "pre" (2.2%) or "post" (1.7%) stent delivery (NS). CONCLUSIONS: (1) The use of poloxamer, rather than PBS, as a vehicle increases the efficacy of percutaneous adenovirus-mediated gene transfer and reduces transfection time; (2) gene transfer performed during stent implantation with poloxamer is feasible and achieves a significant level of gene expression. Thus percutaneous gene delivery is applicable to conventional stents and could present an attractive method by which to achieve local biological effects in a stent environment.

Adenoviruses, Human↗
PubMed1998

Pre-treatment with elastase improves the efficiency of percutaneous adenovirus-mediated gene transfer to the arterial media.

The endothelium and internal elastic lamina (IEL) appear to be the main barriers to adenovirus-mediated gene transfer to medial smooth muscle cells (SMC). The present randomized study tested whether controlled incubation with elastase enhanced the efficiency of catheter-based gene transfer to medial SMC by adenoviral vectors. After an initial safety dose ranging study, rabbits underwent balloon abrasion of the iliac endothelium followed by local incubation of either elastase (2 x 10(-7) IU over 5 min) or saline using a double balloon catheter (DBC). Then, adenoviral vectors (5 x 10(9) p.f.u.) carrying Cmv-Luc or RSV-beta gal reporter genes were instilled for 30 min. Three days later, the number of medial SMC expressing lacZ was increased in the elastase-treated arteries compared with saline-treated arteries (7.2 +/- 2.5 versus 2.3 +/- 0.9 cells per section, P = 0.003). Likewise, the amount of luciferase protein product was increased (70 +/- 32 versus 36 +/- 15 pg luciferase/mg tissue, P = 0.03). No vessel enlargement, light or electron microscopic evidence of injury or inflammation was seen in elastase-treated arteries up to 7 weeks. Preincubation with elastase increased transduction efficiency of catheter-based gene delivery of replication-defective adenoviral vectors to rabbit iliac arteries without detectable arterial damage.

Adenoviridae↗
PubMed1998

Arterial response to mild balloon injury in the normal rabbit: evidence for low proliferation rate in the adventitia.

BACKGROUND: The role of constrictive remodeling, spasm and proliferation (particularly in the adventitia) in the genesis of chronic lumen narrowing after balloon injury remains under debate. This study analyzed the time course of these components following mild injury in normal arteries. METHODS: Iliac injury was induced by balloon overstretch in 32 rabbits, sacrificed at timed intervals from day 3 to 28. Angiographic response to nitrates, morphometric, immunohistochemical and biochemical analysis were performed at each time point. RESULTS: Quantitative angiography showed a decrease in lumen diameter and no change in response to nitrates over time. On morphometric analysis, remodeling was usually constrictive, appeared as early as day 3 and was responsible for 69+/-14% of the histologic lumen area stenosis at day 28. Constrictive remodeling was correlated negatively to intimal hyperplasia (r= 0.51, P< 0.002) and positively to the lumen area stenosis (r= 0.92, P< 0.0001). Macrophages (labeled by anti-RAM 11 antibodies) were very rare at all time points. Immunohistochemistry identified a high rate of proliferating smooth muscle cells in the media (13+/-7%) and intima (49+/-8%) at day 7, which decreased rapidly. Proliferating cells in the adventitia were rare (3+/-2% at day 7). The number of proliferating cells was time-dependent (r= 0.82, P< 0.0001) and related to cyclin A mRNA measured by reverse transcription-polymerase chain reaction (r= 0.84, P< 0.0001). CONCLUSIONS: In this model, luminal loss was mainly caused by constrictive remodeling rather than intimal hyperplasia. Constrictive remodeling appeared early and was not time-dependent. Macrophages, spasm and adventitial proliferation did not contribute to this constrictive remodeling.

Angioplasty, Balloon↗
PubMed1997

Accelerated endothelialization by local delivery of recombinant human vascular endothelial growth factor reduces in-stent intimal formation.

Endothelium plays an important role in vascular smooth muscle cell proliferation and thrombus deposition. We thus hypothesized that local delivery of recombinant human vascular endothelial growth factor (rhVEGF) might reduce in-stent intimal formation. Balloon injury followed by Palmaz-Schatz stent implantation was performed in the external iliac artery of 30 New Zealand rabbits. Animals were then randomized to: 1) no local delivery (Control group, n=10); 2) local delivery via a channel balloon catheter of 100 microg rhVEGF165 (VEGF group, n=10); or 3) local delivery of the vehicle solution (Vehicle group, n=10). Animals were sacrificed 28 days later and morphometric analysis was performed. Maximal intimal area was reduced from 1.47+/-0.12 mm2 and 1.44+/-0.10 mm2 in the Control and Vehicle groups, respectively, to 0.87+/-0.06 mm2 in the VEGF group (p<.001). Accelerated endothelialization by local delivery of an endothelial-specific growth factor, rhVEGF, significantly reduces in-stent intimal formation and could constitute an attractive alternative to direct antiproliferative strategies.

Animals↗
PubMed1997

Evidence for the rapid onset of apoptosis in medial smooth muscle cells after balloon injury.

BACKGROUND: Vascular myocyte apoptotic cell death has been reported in human atherectomy and endarterectomy specimens and for neointimal smooth muscle cells (SMCs) in balloon-injured rat carotid arteries between 7 and 30 days after injury. However, the immediate effect of balloon injury on medial SMC viability has not been examined. METHODS AND RESULTS: Rat carotid arteries were harvested at the time of balloon injury (T = 0) and at 0.5, 1, 2, and 4 hours after injury. Uninjured vessels or vessels harvested at the time of injury (T = 0) did not display evidence of apoptosis. However, as early as 30 minutes after injury, 70% of medial SMCs appeared apoptotic by TdT-mediated dUTP nick end labeling (TUNEL) analysis and by the appearance of condensed chromatin. High frequencies of TUNEL-positive cells were also observed at 1 and 2 hours after injury but not at 4 hours. Transmission electron microscopy revealed many cells with morphological characteristics of apoptosis in the injured sections. A marked decrease in bcl-X expression was detected in the most luminal layers of the media. To corroborate these findings in a second animal model, rabbit external iliac arteries were analyzed after balloon angioplasty. Apoptotic cell death was evident in rabbit arteries at 30 minutes and at 4 hours after injury. CONCLUSIONS: As early as 30 minutes after balloon injury, myocytes appear to undergo apoptotic cell death at a high frequency as shown by TUNEL staining, chromatin condensation, and the appearance of morphological features in electron micrographs. The induction of apoptosis coincides with a marked downregulation of bcl-X expression.

Angioplasty, Balloon↗
PubMed1997

Stent endothelialization. Time course, impact of local catheter delivery, feasibility of recombinant protein administration, and response to cytokine expedition.

BACKGROUND: Because prior studies have established the critical role of the endothelium in preventing vascular thrombosis and intimal thickening, we designed a series of experiments to determine the feasibility of percutaneous local catheter delivery of recombinant protein to accelerate development of an intact endothelial monolayer after stent implantation. METHODS AND RESULTS: Balloon injury followed by percutaneous delivery of a 15-mm-long, balloon-expandable metallic stent was performed in 64 rabbit external iliac arteries (baseline diameter, 2.67 +/- 0.07 mm). Planimetric time-course analysis disclosed < 20% stent endothelialization at 4 days, < 40% at 7 days, and near-complete endothelialization at 28 days. The reporter protein horseradish peroxidase and the endothelial cell-specific recombinant protein vascular endothelial growth factor (VEGF) were each effectively delivered from a local delivery catheter (channel balloon catheter, ChB) after stent implantation. Although local catheter delivery (of vehicle control) itself mildly retarded the extent of stent endothelialization (10.6 +/- 2.9%) versus no local delivery (25.5 +/- 6.6%, P = .045), local ChB delivery of 100 micrograms VEGF overcame this catheter effect: By day 7, stent endothelialization was nearly complete (91.8 +/- 3.8%) (P < .0001 versus no local delivery). Consequently, stent thrombus was reduced in the VEGF-treated group (mural thrombus, 5.3 +/- 3.7%) versus no local delivery (29.3 +/- 6.8%, P = .006). Occlusive thrombus was seen only in the absence of local VEGF administration. CONCLUSIONS: (1) Local delivery of recombinant protein to the arterial wall is feasible after stent implantation, and (2) local delivery of the endothelial cell mitogen VEGF accelerates stent endothelialization, reducing stent thrombosis. These results thus establish a novel means by which the safety and/or bioactivity of endovascular stents may be further enhanced.

Angiography↗
PubMed1997

Early versus late coronary stenting following acute myocardial infarction: results of the STENTIM I Study (French Registry of Stenting in Acute Myocardial Infarction).

This study was undertaken to determine the feasibility and safety of coronary stenting in acute myocardial infarction (AMI). In AMI, primary percutaneous transluminal coronary angioplasty (PTCA) is accepted as the preferred method of reperfusion for patients presenting at highly experienced centres. Until recently, however, stenting has been avoided during AMI because of a potential high risk of thrombosis. This prospective observational study carried out in 20 centres and included 648 consecutive patients who underwent PTCA with stent implantation for AMI. Of these 648 patients, 269 (41.5%, Group 1) were dilated early (< 24 hr) after the onset of the symptoms (75% treated by direct PTCA) and 379 (58.5%, Group 2) were dilated between 24 hr and 14 days after AMI. Combined therapy with ticlopidin and aspirin was used after the procedure. Bailout stenting occurred more often in Group 1 than in Group 2 (17% vs. 9.5%)(P < 0.05). Angiographic successful stenting was similar in both groups of patients (96% vs. 97%). During the hospital follow-up period, stent thrombosis occurred in eight patients (3%) in Group 1 and in six patients (1.6%) in Group 2 (NS). There was 14 deaths (5.2%) in Group 1 and 11 deaths (3.9%) in Group 2 (NS). After multivariate analysis bailout stenting was identified as the sole predictor of stent thrombosis (P < 0.0001). Vascular access-site complications occurred in six patients (1%) with no difference between the two groups. This study indicates that patients who receive a coronary stent in AMI can be managed safely with antiplatelet therapy. Randomized studies are needed to determine the precise indication for coronary stenting as an adjunct to primary PTCA.

Adult↗
PubMed1997

Percutaneous delivery of the gax gene inhibits vessel stenosis in a rabbit model of balloon angioplasty.

OBJECTIVES: The expression of gax, an anti-proliferative homeobox gene, is rapidly downregulated in vascular smooth muscle cells (VSMCs) following arterial injury. Here we performed percutaneous adenovirus-mediated gene transfer into the iliac arteries of normal rabbits using a channel balloon catheter to assess the effects of gax overexpression on neointima formation, lumen diameter, reendothelialization and functional vasomotion. METHODS: A channel balloon catheter was used to perform both the arterial injury and local gene delivery. In each animal both iliac arteries were randomly assigned to receive either an adenovirus expressing the gax gene (Ad-Gax) or the beta-galactosidase gene (Ad-beta gal). In a second group of animals arteries were randomly assigned to receive either Ad-beta gal or saline. RESULTS: At one month, angiography revealed 36% less luminal narrowing in the Ad-Gax-treated arteries relative to the Ad-beta gal-treated control arteries. Histological analysis revealed that the intimal/medial ratio (I/M) was reduced by 56% in the Ad-Gax group. Endothelium-dependent vasomotion was not affected by the gax gene transfer. In the second group, no statistically significant differences were found between the saline and the Ad-beta gal-treated vessels for any of these parameters. CONCLUSIONS: Percutaneous adenovirus delivery of the gax gene to rabbit iliac arteries following endothelial denudation and vessel wall injury reduces neointimal hyperplasia and luminal stenosis, but does not affect endothelium-dependent vasomotion. This study demonstrates that a VSMC transcription factor can potentially be utilized for the development of a molecular therapy for vascular disorders.

Adenoviridae↗
PubMed1997

Passivation of metallic stents after arterial gene transfer of phVEGF165 inhibits thrombus formation and intimal thickening.

OBJECTIVES: This study sought to test the hypothesis that direct gene transfer of an endothelial cell mitogen could passivate metallic stents by accelerating endothelialization of the prosthesis. BACKGROUND: Thrombosis and restenosis comprise the principal clinical manifestations of compromised biocompatibility of endovascular stents. Previous studies have demonstrated that endothelial recovery at sites of balloon injury is a critical determinant of consequent intimal thickening and mural thrombus. We therefore investigated the potential for an endothelial cell mitogen delivered as plasmid DNA to optimize stent biocompatibility. METHODS: Naked plasmid DNA encoding vascular endothelial growth factor (VEGF)/vascular permeability factor (VPF) (phVEGF165) was delivered locally using a hydrogel-coated balloon angioplasty catheter to 16 rabbit iliac arteries in which metallic stents had been placed at the site of balloon injury; the contralateral iliac artery of each rabbit was balloon injured and stented but not transfected. RESULTS: Stent endothelialization was accelerated by phVEGF165 gene transfer (87.38 +/- 5.06% vs. 33.13 +/- 9.73% [mean +/- SEM] of the planimetered stent surface in the treated vs. contralateral limb, p = 0.005). This was associated with a significant reduction in mural thrombus (3.7 +/- 2.4% vs. 32.7 +/- 9.7%, p = 0.01) at day 7 and intimal thickening (maximal intimal area 0.61 +/- 0.09 vs. 1.44 +/- 0.12 mm2, p < 0.0001) at day 28. No benefit was observed from pCMV-luciferase in 14 similarly instrumented control rabbits. CONCLUSIONS: These findings indicate that arterial gene transfer of naked plasmid DNA encoding for an endothelial cell mitogen may successfully passivate endovascular stents by accelerating stent endothelialization, thereby reducing in-stent thrombus and obstruction due to intimal thickening.

Angioplasty, Balloon↗
PubMed1997

[Implantation of coronary stent during the acute phase of myocardial infarction for treatment of dissection or partial result after angioplasty. Immediate results and angiographic follow-up].

Between December 1991 and November 1994, a Palmaz-Schatz stent was implanted in 9 patients aged 57 +/- 14 years during the acute phase of myocardial infarction after primary angioplasty in 7 cases and salvage angioplasty in 2 cases after an interval of 175 mm +/- 62 mn from the onset of infarction, because of threatening dissection (N = 8) or a partial result (N = 1). The success rate of implantation was 100% with residual stenosis (DCI Philips system) measured at 16 +/- 8% (5 to 28%). Anticoagulant treatment comprised heparin, coumadin and aspirin in two cases, and, in the following 7 cases, low molecular weight heparin, ticlopidine and aspirin. There was one death due to cardiogenic shock on the third day despite intraaortic balloon pumping. One patient was operated for a femoral aneurysm. A prophylactic bypass procedure was performed as a semi-emergency in a stable patient. At systematic angiographic control, the residual stenosis was measured at 19 +/- 14% (10 to 43%) without reocclusion. There was no recurrence of ischaemia. The authors conclude that the encouraging results of this short series suggest that despite the highly thrombogenic situation of acute myocardial infarction and despite the context of emergency implantation of a stent. Palmaz-Schatz stent implantation gives good immediate and long-term results with respect to reocclusion and stenosis.

Adult↗
PubMed1996

Growth-arrest homeobox gene Gax: a molecular strategy to prevent arterial restenosis.

Tissue remodeling and alterations in cellular differentiation occur during atherosclerosis and restenosis following balloon angioplasty, but little is known about the nuclear proteins that regulates these processes. Homeobox genes encode transcription factors that regulate cell growth, differentiation, migration, and body plan formation. The Gax (growth arrest homeobox) gene is expressed in adult cardiovascular tissues. Gax is expressed in normal quiescent smooth muscle cells, but its expression is rapidly down-regulated when these cells are stimulated to proliferate with mitogens. Gax expression is also down-regulated in vascular tissue immediately following balloon injury. These characteristics of Gax suggest it may be required to maintain the non-proliferative or contractile phenotype in vascular smooth muscle. Indeed, the mitogen-induced proliferation of cultured vascular smooth muscle cells is inhibited when these cells are microinjected with recombinant Gax protein. Gax also inhibits the proliferation of vascular smooth muscle cells when overexpressed with a replication-defective adenovirus vector, and the local delivery of this recombinant virus to denuded rat carotid arteries significantly reduces neointima formation and luminal narrowing. Currently we are performing percutaneous Gax adenovirus-mediated gene transfer into normal and atherosclerotic rabbit iliac arteries. These data suggest that overexpression of Gax gene may prevent the neointimal formation that is characteristic of a number of vascular disorders.

Angioplasty, Balloon↗
PubMed1996

[Acute basal ganglia necrosis with favorable course during Mycoplasma encepahlitis].

BACKGROUND: Acute bilateral striatal necrosis complicating the course of a post-infectious encephalitis is rare. CASE REPORT: A previously healthy 5-year-old boy presented with an atypical pneumonia; he rapidly developed, encephalitis revealed by a generalized status epilepticus. After transient improvement, he became confused and mutic, with dystonic postures of his limbs. Painful stimulation resulted in prolonged facial grimacing and doleful cry. CT scan and MRI showed abnormal signals in the whole basal ganglia, typical of bilateral striatal necrosis. Serologic tests for Mycoplasma pneumoniae were positive. The child recovered almost completely. CONCLUSION: A parainfectious process is probably responsible for the transient bilateral striatal necrosis seen in this patient who had Mycoplasma pneumoniae infection several days before the onset of neurologic symptoms. MRI seemed more reliable than CT-scan for the diagnosis of this condition.

Acute Disease↗