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H Lacroix

Publications and source records attributed to H Lacroix.

At least 55 records · Page 3Linked to original sources
PubMed1995

Recurrent aortic infection: treatment by arterial homograft replacement.

Deep infection remains the most problematic complication following prosthetic aortoiliofemoral reconstruction. Prosthetic excision and extra-anatomic revascularization is associated with significant morbidity and mortality. The possibilities of autogenous reconstruction are frequently limited. The authors present a patient with recurrent aortic infection who was successfully treated by prosthetic excision and revascularization in situ with a cryopreserved arterial homograft.

Aneurysm, Infected↗
PubMed1995

Autogenous reconstruction with the lower extremity deep veins: an alternative treatment of prosthetic infection after reconstructive surgery for aortoiliac disease.

PURPOSE: This report evaluates the efficiency of use of the lower extremity deep vein as arterial conduits in the autogenous repair of prosthetic infection after reconstructive aortoiliac surgery. METHODS: We reviewed our records for the period 1990 to 1994 of all patients with prosthetic infection after reconstruction for aortoiliac disease, and we selected for this study all those patients who underwent autograft repair with the lower extremity deep veins. RESULTS: Included were 15 patients: 12 had previously undergone direct aorto(ilio)femoral reconstruction, and three had an extraanatomic prosthetic graft. Thirteen patients were admitted with primary graft infection, and two were admitted with secondary graft-enteric erosion. Treatment consisted of prosthetic excision and aorto(ilio)femoral reconstruction with the superficial femoral vein. In situ reconstruction was performed in 12 cases. The operative mortality rate was 7%. There were no early graft occlusions. One patient underwent an above-knee amputation because of concomitant femoropopliteal occlusion in the presence of a patent deep venous aortofemoral graft. Early postoperative limb swelling was common and was controlled with bed rest, elastic stockings, or intermittent pneumatic compression. The mean follow-up of this series was 17 months (range 4 to 33 months). Two patients died of unrelated causes. One graft occluded after 16 months. There were no reinfections, and all but one patient resumed normal daily activities. Disability from removal of the deep veins was minimal: only one patient continues to wear elastic stockings for limb swelling and shows signs of venous hypertension more than 2 years after surgery. CONCLUSION: Harvesting of the lower extremity deep veins is well tolerated. Autogenous reconstruction with these veins provides good potential for salvage of life and limbs in case of prosthetic infection. A longer period of follow-up is required to study the long-term behavior of these grafts and to allow definite comparison with more conventional approaches.

Aged↗
PubMed1995

Role of 1,2-sn diacylglycerol in airway smooth muscle stimulated by carbachol.

Activation of muscarinic receptors in airway smooth muscle leads to breakdown of membrane polyphosphoinositides. In agreement with others, we show here that muscarinic stimulation elicits inositol-1,4,5-triphosphate formation. In addition, we show that carbachol also elicits total diacylglycerol and 1,2-sn diacylglycerol accumulation in a specific and dose-dependent manner (EC50 values: 2.1 x 10(-8) M for 1,2-sn diacylglycerol). The time-course of inositol-1,4,5-triphosphate accumulation is compatible with that of the clonic phase of muscle contraction. Since this derivative can mobilize intracellular Ca2+ stores, it may play a second-messenger role in the initial phase of contraction. The time-course of diacylglycerol accumulation is compatible with the muscarinic-induced tonic phase of smooth-muscle contraction. Carbachol induces similar dose-dependent reductions in isoproterenol-induced muscle relaxation (EC50 values for relaxation concentration-response curves to isoproterenol: 3 x 10(-6) M and 2.1 x 10(-5) M, with carbachol at 10(-7) M and 10(-4) M, respectively), and increases in adenylate cyclase activity (EC50 values for the concentration-response to isoproterenol: 1.2 x 10(-6) M and 1.5 x 10(-5) M, with carbachol at 10(-7) M and 10(-4) M, respectively). Since it is known that carbachol-induced uncoupling of beta 2-adrenergic receptors is proportional to the breakdown of polyphosphoinositides, and that 1,2-sn diacylglycerol is a potent activator of protein kinase C, 1,2-sn diacylglycerol could be mediating the uncoupling of beta 2-adrenergic receptors, via activation of alpha-protein kinase C and subsequent phosphorylation of receptor, and/or cyclase, and/or G proteins.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenylyl Cyclases↗
PubMed1995

Nedocromil sodium reduces cigarette smoke-induced bronchoconstrictor hyperresponsiveness to substance P in the guinea-pig.

Acute exposure to cigarette smoke provokes airway hyperresponsiveness to substance P and inactivates neutral endopeptidase (NEP). To determine whether nedocromil sodium can prevent cigarette smoke-induced hyperresponsiveness to substance P, we studied two groups of anaesthetized guinea-pigs. One group of guinea-pigs was pretreated with aerosolized 0.9% NaCl solution (90 breaths), the other group was pretreated with aerosolized nedocromil sodium (10(-4) M, 90 breaths). In each animal, pretreatment was followed by either exposure to the smoke of one cigarette or exposure to air. After acute exposure to cigarette smoke or to air, we measured the change in total pulmonary resistance (RL) induced by increasing concentrations of aerosolized substance P. In the absence of nedocromil sodium, the bronchoconstrictor responses to substance P were greater in cigarette smoke-exposed guinea-pigs than in air-exposed animals. Aerosolized nedocromil sodium had no effect on the response to substance P in air-exposed animals, but it reduced cigarette smoke-induced hyperresponsiveness to substance P. The preventive effect on cigarette smoke-induced hyperresponsiveness to substance P was observed at concentrations of aerosolized nedocromil sodium of 3 x 10(-5), 10(-4), and 3 x 10(-4) M. In vitro, cigarette smoke solution inhibited NEP activity from lung membrane preparations, but this inhibitory effect was not modified by nedocromil sodium (10(-4) M). We conclude that aerosolized nedocromil sodium reduces cigarette smoke-induced airway hyperresponsiveness to substance P in vivo. This action of nedocromil sodium is not due to a protective effect on cigarette smoke-induced inactivation of NEP in vitro.

Aerosols↗
PubMed1995

Prevention of fracture at the distal locking site of the gamma nail. A biomechanical study.

To investigate the origin of fractures at the distal locking site of the Gamma nail, we loaded ten paired human cadaver femora fixed with a Gamma nail in torsion until they fractured. When an awl was hammered in to start the hole for distal locking a fissure appeared in the lateral cortex of all the femora, and the mean torsional load to create a fracture was reduced by 57.8% compared with that in a control group in which the distal locking hole had been started with a centre drill. When an additional drill hole was made, the mean failure load in torsion decreased by 35.7%. We strongly recommend that an awl should not be used at the distal locking site of the Gamma nail; we recommend the use of a centre drill. Additional drill holes should be avoided because they act as stress raisers.

Femoral Fractures↗
PubMed1995

[Efficacy of the combination of mitomycin, ifosfamide and cisplatin with irradiation for the treatment of cerebral metastasis in non small cell lung carcinoma].

We initiated prospective study testing efficacy of multidrug chemotherapy (cisplatin, ifosfamide, mitomycin) with irradiation in brain metastases of non small cell lung cancer at first diagnosis. Among 22 patients we obtained ten objective local responses (45%). Median survival was 7 months. Toxicity was mild (> 2 - OMS): hematologic = five patients; gastrointestinal = one patient. Among 11 patients who received chemotherapy before radiotherapy we had seven objective responses (patients evaluated after three courses of chemotherapy and before radiotherapy). This result indicates the interest of this protocol of chemotherapy in brain metastases. The association of this protocol of chemotherapy and radiotherapy appears effective, well tolerated and few toxic.

Adult↗
PubMed1994

Local thrombolysis for occluded arterial grafts: is the yield worth the effort?

This study reports the results and complications of local thrombolytic therapy of 50 recently occluded grafts. These occurred in 41 patients with acute severe but still reversible ischemia. The majority were infra-inguinal synthetic grafts. Thrombolysis was induced with urokinase (n = 1), streptokinase (n = 11) or alteplase (n = 38) via an intra-arterial catheter. Complete angiographical lysis was obtained in 36 grafts (72%) and partial lysis in 6 (12%). The highest lysis rate was obtained with alteplase (32/36; 89%). Complementary endovascular and/or surgical intervention was needed in 17 patients to correct an underlying stenosis and/or to save the limb. Fifteen complications occurred (30%) of which distal embolization (n = 4) and bleeding (n = 8 of which 3 fatal) were the most frequent. Six of the bleeding episodes occurred in patients on chronic aspirin intake. The late results were poor. At six months, the primary patency of successfully lysed grafts dropped to 19% and the limb salvage rate to 64%. Thrombolytic therapy is far from the ideal management of thrombosed grafts: maintenance of restored patency is the challenge.

Acute Disease↗
PubMed1994

Carotid artery surgery in the presence of an occlusion of the contralateral carotid artery: perioperative risk analysis and follow-up.

A retrospective study of 129 carotid artery reconstructions with an occlusion of the contralateral internal carotid artery (group CO) is presented. A control group comprised 489 patients with a stenosis of < 50% at the contralateral side (group CN). Both groups had the same mean age. There were fewer women in group CO (14% versus 31%, P < 0.0001), and more patients had a history of coronary heart disease (57% versus 44%, P < 0.05). In addition more patients of group CO had suffered a stroke (36% versus 27%, P < 0.05). A temporary shunt was used selectively and more frequently in group CO (87% versus 31%, P < 0.001). Major postoperative complications occurred with equal frequency in both groups: all strokes plus non-cerebral mortality (total combined morbidity and mortality): 4.65% versus 5.5%. The late incidence of stroke was the same in both groups: 8% in CO and 7% in CN at 5 years. The authors conclude that, under the described circumstances and with the appropriate surgical technique, the presence of an occlusion of the contralateral internal carotid artery does not imply an increase in major postoperative complications nor a higher stroke rate during follow-up.

Aged↗
PubMed1994

Influence of exogenous porcine growth hormone on magnesium metabolism in intact pigs receiving normal magnesium intakes.

The magnesium balance and plasma magnesium levels of intact growing pigs treated with recombinant porcine growth hormone (100 micrograms/kg body weight/d) for 2 months were measured. Growth hormone treatment did not change plasma magnesium, but it markedly increased magnesium absorption and retention. This agrees with our finding of adequately mineralized newly formed bone in intact pigs given growth hormone.

Animals↗
PubMed1994

[Approach to aortic aneurysms including the renal arteries: retroperitoneal method].

A pararenal aneurysm is a rare type of an abdominal aortic aneurysm. The authors report 25 cases out of 429 abdominal aneurysms. The diagnosis was based on a CT-scan and subsequent biplane arteriography. The most common type was the dorsal proximal aortic dilatation, involving the origin of 1 or 2 renal arteries. A retroperitoneal approach was used in 18 of the 25 patients. The most common complication was the retroperitoneal hemorrhage, necessitating reintervention. None of these patients died or developed renal insufficiency despite a suprarenal clamping during the proximal reconstruction.

Aged↗
PubMed1993

The superficial femoral vein as autogenous conduit in the treatment of prosthetic arterial infection.

Autogenous reconstruction is a well-accepted alternative treatment for prosthetic infection after reconstructive arterial surgery. Because of its technical complexity and the lack of suitable substitutes, the procedure remains limited to a few selected centers. We describe four patients with prosthetic infection after reconstructive surgery for lower limb ischemia. Treatment consisted of prosthetic excision and aortofemoral grafting with the use of the superficial femoral vein. All patients survived the operation and infection was eradicated in all cases. We conclude that the superficial femoral vein represents an acceptable arterial conduit in the treatment of these difficult cases.

Aged↗
PubMed1993

Blood pressure management during aortic surgery: urapidil compared to isosorbide dinitrate.

The efficacy and hemodynamic effects of urapidil, an arteriolar vasodilator, and isosorbide dinitrate, a venodilator, were compared, when used for blood pressure control during abdominal aortic surgery. Urapidil is an alpha-adrenergic receptor antagonist with serotonin-1A receptor-agonist activity in the central nervous system. Hemodynamic profiles were recorded before and after the administration of the study drug (+/- 10 minutes before aortic clamping), 3 and 10 minutes following aortic clamping, and before and 3 and 10 minutes following the removal of the aortic clamp. Arterial and mixed venous oxygen contents were compared. Both groups of 18 patients were similar with respect to demographic profiles, anesthetic technique, and perioperative fluid therapy. Identical heart rate and blood pressure profiles were obtained. In contrast to isosorbide dinitrate, urapidil produced a 17% (P < 0.05) increase in cardiac index as a result of a 30% (P < 0.001) decrease in systemic vascular resistance before placement of the aortic clamp. In patients treated with urapidil, cardiac index was higher (P < 0.05) 10 minutes after aortic clamping, before removal of the clamp, and 10 minutes later. The arterio-venous oxygen content difference decreased from 3.2 +/- 0.8 mL O2/dL to 2.4 +/- 1.0 mL O2/dL (P < 0.01) following urapidil, but did not change during the administration of isosorbide dinitrate. It is concluded that urapidil is an effective and safe drug for the prevention of the hemodynamic consequences of aortic clamping. Compared to a venodilator (isosorbide dinitrate), urapidil offers the advantage of improving cardiac output and oxygen delivery.

Alfentanil↗
PubMed1992

Carboxypeptidase M-like enzyme modulates the noncholinergic bronchoconstrictor response in guinea pig.

We studied the effects of aerosolized DL-2-mercaptomethyl-3-guanidino-ethylthiopropanoic acid (MGTA) (10(-4) M, 90 breaths), a specific inhibitor of carboxypeptidase B-type enzymes, on changes in total pulmonary resistance (RL) induced by aerosolized capsaicin (10(-7) to 10(-4) M; 10 breaths at each concentration) and vagus nerve stimulation (5 V, 5 ms, for 20 s at frequencies varying from 2 to 10 Hz) in anesthetized, atropinized, and ventilated guinea pigs. We also studied the effect of aerosolized MGTA on the bronchoconstrictor response to either aerosolized substance P, neurokinin A (10(-7) to 10(-4) M; 10 breaths at each concentration), and carbachol (10(-5) to 2 x 10(-4) M; 10 breaths at each concentration) or to i.v. administration of neurokinin A (10(-11) to 10(-8) mol/kg), bradykinin (10(-10) to 10(-7) mol/kg), and histamine (10(-8) to 10(-6) mol/kg). Although aerosolized MGTA caused no change in basal RL (P > 0.5), it did potentiate the noncholinergic bronchoconstrictor response to capsaicin (n = 5; P < 0.001) as well as to vagus nerve stimulation (n = 5; P = 0.001). In contrast, MGTA did not potentiate the bronchoconstrictor response to either aerosolized substance P, neurokinin A, and carbachol or to i.v. administration of neurokinin A, histamine, and bradykinin. Carboxypeptidase activity cleaving C-terminal arginine or lysine was found in the membrane preparations of trachea and lung from guinea pigs. The membrane-bound carboxypeptidase activity was maximal at pH 7.0 and was enhanced by the presence of CoCl2 (1 mM) in both the tracheal and lung tissue.(ABSTRACT TRUNCATED AT 250 WORDS)

3-Mercaptopropionic Acid↗