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Biomedical subjects

D Roux

Publications and source records attributed to D Roux.

At least 91 records · Page 5Linked to original sources
PubMed1993

Na/H exchange activities in NHE1-transfected OK-cells: cell polarity and regulation.

The human fibroblast, "amiloride-sensitive" Na/H exchanger (NHE1) was transfected into opossum kidney cells (OK cells) (OK/NHE1 cells). Northern blot analysis confirmed that the NHE1 message is expressed in OK/NHE1 cells. In immunoblot analysis, an anti-human NHE1 antibody labelled a membrane protein only present in OK/NHE1 cells. In contrast to the parental cell line containing only an apically located, "amiloride-resistant" Na/H exchange activity, OK/NHE1 cells contain apically and basolaterally located Na/H exchange activities, the apical activity being "amiloride resistant" and the basolateral being "amiloride sensitive". Parathyroid hormone (PTH) inhibited apical transport activity (OK and OK/NHE1 cells) but had no effect on basolateral transport activity (OK/NHE1 cells). Pharmacological activation of protein kinase A (forskolin) decreased both apical and basolateral Na/H exchange activity. Incubation with phorbol ester (exogenous activation of protein kinase C) reduced apical Na/H exchange activity (OK and OK/NHE1 cells) but had only a moderate, inhibitory effect on basolateral Na/H exchange activity (OK/NHE1 cells). These results indicate that transfection of OK cells with human fibroblast NHE1 cDNA encoding an "amiloride-sensitive" form of the Na/H exchanger results in expression of basolaterally located "NHE1-related" transport activity. Regulatory control of intracellular Na/H exchange activities (apically versus basolaterally located) and intercellular Na/H exchange activities (NHE1-related) differs. This may relate to cell-specific properties as well as to exchanger-specific properties.

Amiloride↗
PubMed1993

A biometric analysis in the rat of the horizontal component of physiological tooth migration and its response to altered occlusal function.

The direction and amplitude of physiological tooth migration, as well as the influence of occlusal force on this movement, were evaluated macroscopically in the rat by biometric means. The first experiment, which compared the position of the teeth in the anteroposterior plane of the maxilla between two groups of 20 and 28 rats killed at age 15 and 52 weeks, respectively, confirmed the distal direction of this drift. In a second experiment, after suppression of the antagonist occlusal contacts of the maxillary left dental hemiarch in nine rats, the migration of this hemiarch was compared to that of the hyperfunctional contralateral hemiarch and to that of the molars in a control group of 20 rats. A statistically significant (t-test) reduction of the physiological migration in the absence of occlusion, was revealed.

Animals↗
PubMed1993

Subaortic obstruction in double outlet right ventricles. Surgical considerations for anatomic repair.

BACKGROUND: Subaortic obstruction is one of the risk factors for anatomic repair of double outlet right ventricles (DORV). A comprehensive approach to such lesions has been developed in our institution since 1981. This retrospective work analyzes the results of this approach. METHODS AND RESULTS: Between January 1981 and September 1992, 30 patients aged 15 days to 15 years (mean, 44.8 months) underwent repair of a DORV associated with subaortic obstruction. Eighteen patients had a palliative procedure before complete repair. The ventricular septal defect (VSD) was subaortic in 15 patients, doubly committed in 1, noncommitted in 9, and subpulmonary in 5. The subaortic obstruction was a result of restrictive VSD in 29 patients and of double straddling of mitral and tricuspid valves once. The preoperative peak systolic pressure gradient between the left ventricle and the aorta (LV-Ao) was 68.7 +/- 23 mm Hg. Reconstruction of the left ventricular outflow tract comprised a ventral enlargement of the VSD in subaortic, doubly committed, and those subpulmonary VSDs scheduled for an arterial switch operation or a conal resection in noncommitted and other subpulmonary forms. Reconstruction of the right ventricular outflow tract included primary closure of the right ventricle in 12 patients, an infundibular patch in 9, a transannular patch in 4, and insertion of a right ventricular pulmonary valved conduit in 5. There were two early (6.6%) and two late (7.1%) deaths. Three patients required reoperation. A mean follow-up of 60.5 +/- 46.8 months was achieved in all the survivors. They were all in New York Heart Association class I or II, in sinus rhythm. At last follow-up, the mean LV-Ao gradient was 7.5 +/- 6.2 mm Hg, and LV function indices were within normal ranges. Actuarial survival and freedom from reoperation rates at 8 years were 86.6% and 87.0%, respectively. CONCLUSIONS: Surgical relief of subaortic obstruction in DORV has to be adapted to VSD location and spatial arrangement of atrioventricular valves and great vessels.

Aortic Stenosis, Subvalvular↗
PubMed1993

["Paradoxical" pulmonary embolism: migration of an inferior vena cava filter. Apropos of two cases].

Report of two cases of sudden acute pulmonary embolism of an inferior vena cava filter, initially indicated to prevent cruoric pulmonary thrombo-embolism. These two iatrogenic complications were both due to the secondary failure of an interventional percutaneous procedure and led to aggressive and urgent surgical removal of the filter by sternotomy and cardiopulmonary bypass. Discussion of indications and choice of the inferior vena cava filter.

Aged↗
PubMed1992

Cardiac surgical aids: heart cup and stentless valve holder.

We present two new cardiac surgery instruments that we perfected in our department. The heart cup holds the donor's heart vertically within a cold saline solution, thus allowing adequate preparation of the heart for transplantation, as well as the excision of valvular homografts from the recipient's heart. The stentless valve holder is used to hold valvular homografts to ease both their preparation and implantation.

Cardiac Surgical Procedures↗
PubMed1992

Propranolol reduces the rebleeding rate during endoscopic sclerotherapy before variceal obliteration.

In patients treated with sclerotherapy, most rebleeding episodes are observed before variceal obliteration. This prospective randomized study aimed to assess if propranolol together with sclerotherapy could reduce the rebleeding rate before variceal obliteration. Seventy-five patients (59 male, 16 female; mean age, 54 +/- 15 years) with cirrhosis (from alcohol abuse in 91%) admitted with upper gastrointestinal bleeding, which was endoscopically proven to originate from ruptured esophageal varices, were included. After initial control of bleeding, the patients were randomized into the following two groups: group 1 treated with sclerotherapy alone (36 patients) and group 2 treated with sclerotherapy plus propranolol (39 patients). They were followed up to variceal obliteration. In group 2, 7 patients rebled as compared with 14 patients treated with sclerotherapy alone (P less than 0.005). When considering only rebleedings from esophageal varices, 4 patients rebled in group 2 vs. 10 in group 1 (P less than 0.10). The total number of rebleeding episodes was lower in group 2 than in group 1 whether considering all causes (8 vs. 17; P less than 0.07) or variceal rebleedings alone (4 vs. 13; P less than 0.01). Mean total blood requirement per patient was lower in group 2 than in group 1 (1.4 +/- 3.4 vs. 2.79 +/- 6.4 units of blood, respectively; P less than 0.01). Mortality was similar in both groups of patients (14% vs. 13% in groups 1 and 2, respectively, NS). It is concluded that patients treated with sclerotherapy should be given propranolol before variceal obliteration.

Adult↗
PubMed1992

[Myocardial beta-adrenergic receptors and left ventricular hypertrophy induced by pressure overload in man].

In experimental models, the characteristics of beta-adrenoceptors in left ventricular hypertrophy (LVH) due to pressure overload remain controversial and no data are still available in man. We investigated right auricular (RA) and left ventricular (LV) beta-adrenoceptors characteristics (125 I cyanopindolol binding) in two groups of patients undergoing valve replacement without heart failure (LV ejection fraction > 55%). Height patients with mitral stenosis (mean age: 64 +/- 4 years) and without LVH (LV mass index < 120 g/m2) constituted the control group and 13 patients with aortic stenosis (mean age: 66 +/- 4 years) and LVH (LV mass index > 150 g/m2) the study group. The results are: [table: see text] These results show that, in man, LVH due to pressure overload does not induce variation of total number beta-adrenoceptors, but is associated with a selective decrease in left ventricular beta 1-adrenoceptors.

Aged↗
PubMed1992

[Placenta praevia percreta with bladder invasion: a case report].

The authors report a rare case of placenta praevia percreta with bladder invasion giving rise to the need to carry out an emergency hysterectomy in order to stop the bleeding. The literature when analysed showed the possible outcome of this complication in a woman who had already had a caesarean section and who had placenta praevia that required a second caesarean. In this situation it is almost inevitable that a hysterectomy has to be carried out to stop the bleeding. The hysterectomy should be a total hysterectomy but this can be difficult because of the invariable "fusion" that takes place between the uterus and the posterior wall of the bladder. What has to the done bladder can range from simple closure of a hole in the bladder to ureteric diversion with reimplantation of the ureter depending on how badly the bladder has been invaded. In our case after a sub-total hysterectomy had been carried out with simple closure of the bladder, it was necessary to re-operate to treat a fistula between the bladder and the cervix.

Adult↗
PubMed1991

Early postoperative sternal approximation after ITA harvesting: computed tomographic evaluation.

Between November 1989 and February 1990, 66 randomized sternotomized patients underwent aortocoronary bypass and were subjected to a sternal scanner in the early postoperative period. Each examination included a manubrial and a sternal body print. At each level, we studied the occurrence of spacing or misalignment of the sternal layers. The 66 patients were subdivided into four groups according to the type of conduit harvested (single left internal thoracic artery or saphenous vein) and the type of material used for the sternal closure (steel wires or nylon yarns). In all cases, adequate early sternal approximation, which is represented by a good alignment as well as by an excellent contact of the sternal layers, was infrequently demonstrated. Moreover, the two abnormalities most often observed were manubrial spacing and sternal body misalignment. The sternal closure technique and internal thoracic artery harvesting had no significant effect on the sternal approximation. To minimize manubrial spacing and sternal body misalignment, we propose that the surgeon should apply three threads through the manubrium, withdraw the shoulder roll beforehand, elevate both of the patient's shoulders, and maintain the two xyphoid layers in the same plane and in fairly close contact during the tightening of the wires.

Aged↗
PubMed1991

Clinical evaluation of the accuracy of the Evident RCM Mark II Apex Locator.

The accuracy of the Evident RCM Mark II in locating the apical foramen was evaluated in 37 human teeth scheduled for extraction. After extraction, the difference between the position of the apical foramen determined electronically and its real anatomical location was measured under a binocular microscope, using a micrometer mobile in x, y, and z coordinates. The results show that in 86% (n = 37) of the cases, an accurate location +/- 0.5 mm of the apical foramen was obtained.

Adolescent↗