Search PubMed⌕ Search

Biomedical subjects

A Coste

Publications and source records attributed to A Coste.

At least 19 recordsLinked to original sources
PubMed1992

[Results of the treatment of aspergillosis of the maxillary sinus by exclusive middle meatotomy approach].

Over a 3 year period the authors have managed 12 immune competent patients with aspergillosis of the maxillary sinus by intranasal sinus surgery using only a middle meatal approach. An enlarged middle meatal window was formed by resection of the superior surface of the inferior turbinate. especially designed curve suction tubes and forceps were used to reach all areas of the maxillary sinus in order to perform a macroscopically complete resection of all lesions. On no occasion Aspergillus was the alternative use of an inferior meatal window or a Caldwell-Luc approach necessary. The authors conclude that the use of a middle meatotomy for the surgical treatment of aspergillosis of the maxillary sinus makes it possible to assure complete resection, to adapt post-operative care and to permit prolonged aeration of the sinus.

Aspergillosis↗
PubMed1992

[Inverted papilloma of the nose and paranasal sinuses. Retrospective study of 18 cases].

The authors report about 18 cases of inverted papillomas treated between 1981 and 1991. The average age of the patients is 51 years, with a marked male predominance. The average follow-up is of 4 years. The most often noted revealing sign is unilateral nasal obstruction. A history of polypectomy and nasosinual surgery is found in 45% of the cases in our series. The treatment was surgical in all cases, including 4 De Lima's procedures, 11 procedures through a paralateronasal approach, 2 ethmoidectomies through an endonasal approach, and 1 degloving for a septal lesion. Endonasal surgery was performed for two limited tumors, for which the diagnosis of inverted papilloma never could be made preoperatively. The recurrence rate observed in our series is 5%. Out of 18 patients, 4 presented with a malignant change, either at once (2 cases) or some time after the primary exeresis of the inverted papilloma (2 cases). In the light of the results, and after analyzing the literature, the authors reassert the necessity of radical exeresis for inverted papilloma. Rhinosinual endoscopy must remain a diagnostic means and never is an indication of exeresis of inverted papilloma. The authors emphasize the difficulty of the histological diagnosis and set forth the various problems arising from the malignant degeneration of inverted papillomas. Recent discoveries on viral etiopathogenesis and on the oncogenic potential of the type-16 papilloma virus may allow characterizing the evolutive and prognostic features of inverted papillomas in the future.

Adult↗
PubMed1991

Stage I-II squamous cell carcinoma of the oral cavity treated by iridium-192: is elective neck dissection indicated?

This is a retrospective analysis of 233 evaluable patients with stage I-II squamous cell carcinoma of the oral cavity treated by definitive branchytherapy. Minimum follow-up is 3 years. Treatment of neck was chosen by a multidisciplinary team, according to age, medical status and availability for regular follow-up. One hundred and ten patients (47%) underwent elective neck dissection (END); 28 (25%) had positive nodes and received neck irradiation post-operatively. One hundred and twenty three patients (53%) were regularly followed up only, with therapeutic neck dissection (TND) reserved for cases of node relapses. In the END group, there were 19 neck relapses (17%): 12/60 (20%) in patients with mobile tongue carcinoma and 7/50 (14%) in patients with floor of the mouth carcinoma. Salvage treatment was successful in 9/19 (47%) cases. In the TND group, there were 21 neck relapses (17%): 16/82 (20%) in patients with mobile tongue carcinoma and 5/41 (10%) in patients with floor of the mouth carcinoma. Salvage treatment was successful in 13/21 (62%) cases. Ten-year survival is 37% for the END group and 31% for the TND group. Tumour stage and infiltration into underlying tissues increased the probability of neck relapse and death. Furthermore, a multivariate analysis showed that patients treated in the TND group had a higher probability of death than patients treated in the END group (p less than 0.04).

Adult↗
PubMed1990

[Conservative transmandibular lateral pharyngectomy in cancer of the lateral oropharyngeal wall].

The authors present conservative transmandibular lateral pharyngectomy (CTLP) as a substitute for BPTM operations in cancers of the tonsillar region. The mandible is sectioned along the symphyses and the oropharynx is widely exposed through an incision of the pelvilingual sulcus. The authors propose a primary operability criterion that allows to salvage the mandibular angle, which is usually sacrificed. This can be assessed peroperatively by testing the possibility to cleave and spread inwardly the pharyngomandibular region following detachment of the pterygoid muscles. The functional and cosmetic benefits of this method are obvious and should commend its more frequent utilization.

Bone Plates↗
PubMed1990

[Amalgamated and reinforced bone powder graft in the correction of the nasal ridge].

A number of surgical procedures have been described to correct irregularities of the consequences of excessive resection of the nasal ridge. Among these procedures the authors propose a bone powder graft mixed with tissue glue and reinforced with surgicel. The graft is in the form of a sheet of variable thickness which is malleable and can be perfectly shaped to fit the nasal ridge. It is positioned between the osteo-cartilagenous supporting structures and the skin. It smoothes out rough areas and compensates for any underlying loss of substance. It may be combined with a bone or cartilage graft which serves as a support and also acts to smoothe out the irregular form of the latter.

Bone Transplantation↗
PubMed1989

[The CO2 broncholaser in the treatment of subglottic and tracheal stenosis. Apropos of 14 cases].

The authors report the results of CO2 broncholaser treatment in 14 cases of iatrogenic cricotracheal stenosis. A stable patency of the laryngotracheal airway was successfully obtained in 43% of stenoses treated with the broncholaser alone. In another 43% of patients improvement was obtained. Failure occurred in 14% of cases. Heat disruption of the cartilagenous support was the most frequent cause of failure and recurrence. The development of rigid bronchoscopes which can be coupled to CO2 laser would appear to us to be a real technical advance. The apparatus is easy to handle and is increasingly being used as first intention. It has several advantages compared to endoscopic materials used with the YAG laser. The effect of CO2 on the tissues would seem to be better adapted than the YAG for iatrogenic stenoses.

Adult↗
PubMed1987

[Clinical study of double-chamber stimulation. Apropos of 50 cases followed-up for 1 to 5 years].

The authors report their experience of dual chamber pacing in 29 men and 21 women of mean age 71 +/- 4 years. 35 had sinus node dysfunction associated with node-His bundle conduction disorders; 31 presented with neurological symptoms and 4 with heart failure (due to pacemaker syndrome in 1 case). Sinus node dysfunction was diagnosed by surface ECG in 25 cases and after electrophysiological studied in only 10 cases. Fifteen patients had atrioventricular block without sinus node dysfunction: 2 of them were young subjects, 1 had pacemaker syndrome and 12 were actual or potential heart failure patients for whom preservation of the atrial systole was justified. Nine patients presented with neurological symptoms. 43 (86%) had cardiac or arterial disease associated with cardiac rhythm and conduction disorders. The percutaneous single subclavian vein approach was used in 36 cases (78%). 41 active and 9 passive fixation electrodes were utilized. The mean follow-up period was 25 months (12 to 70 months), with a cumulative figure of 1,253 months/patients. Two late re-operations for displacement of the atrial electrode were performed. Dual chamber pacing was abandoned, 14 months on average after implantation, in 9 patients (18%), on account of arrhythmias in 4 of them. Three cases of tachycardia from "electronic re-entry" and 6 cases of supraventricular arrhythmia transferred to the ventricle by the pacemaker were observed. Sixteen patients (32%) died 12 +/- 4 months on average after surgery: 12 (33%) had sinus node dysfunction and 4 (26%) had AV block. Death was caused by a cardiovascular disease in 12 cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1986

[Exclusive permanent atrial stimulation. Clinical experience apropos of 65 cases with a follow-up of 1 to 5 years].

The authors report their experience of permanent exclusive atrial pacing in the treatment of sinus node dysfunction in a series of 65 cases with a follow up of 1 to 5 years (average 37.6 months; 2406 patients months), 41 women and 24 men aged 74 +/- 3 years. Sixty one patients were symptomatic. The diagnosis was made from surface ECG recordings in 54 cases (83 p. 100) and after electrophysiological investigation in 11 cases (16 p. 100). Atrioventricular conduction was carefully evaluated before implantation: PR equal to or less than 200 ms, Wenckebach point equal to or greater than 130/min, absence of ventricular pauses longer than 3,000 ms after carotid sinus massage, HV interval equal to or less than 55 ms [measured in 57 cases (87 p. 100)], negative Ajmaline test in 6 patients with intraventricular conduction defects. Performed J-shaped atrial leads with active (66 p. 100) or passive fixations (34 p. 100) were implanted by an endocavitary approach (right subclavian vein in 60 cases: 92 p. 100). There were 3 cases of early lead displacement and one patient developed an elevated threshold of pacing. There were 5 deaths during the follow-up period (3 of cardiovascular origin). The neurological symptoms disappeared in 93 p. 100 of cases. No cases of cardiac failure were observed after permanent pacing. Fifteen patients had documented supraventricular arrhythmias before implantation; 5 patients continued to have the same paroxysmal or permanent arrhythmias but 10 patients had no further recurrences, 8 with and 2 without antiarrhythmic therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1985

Dihydrofolate reductase activity and resistance to aminopterin in various species of Drosophila.

The aim of our work was to compare the mechanisms of resistance to aminopterin, inhibitor of the dihydrofolate reductase enzyme, between different Drosophila species and those described for cultured cells. Moreover we compared the systematic species divisions based on morphological traits and those based on a molecular approach. For this purpose, the effect of aminopterin on viability and wing phenotype was studied in different Drosophila species. Dihydrofolate reductase was measured in adult flies. We found an important dihydrofolate reductase activity in the melanogaster sub-group compared to the other species studies. Wing effect was observed only in this sub-group. The effects of aminopterin on the wing phenotype were very similar to the phenotype of rudimentary mutants. Both deplete the pyrimidine pool and it has been shown by the studies of the structural genes of the nucleotide pyrimidine pathway that the wing tissue is very sensitive to every pertubation of this metabolism. The D. ananassae species was found to be fully resistant at the concentrations of the inhibitor tested. No or very little dihydrofolate reductase activity was detected. The binding of the enzyme to the inhibitor was comparable to that found in the Oregon strain of D. melanogaster. The purine and pyrimidine salvage pathways were investigated and the D. ananassae species displayed an important thymidine kinase activity. The D. ananassae flies were sensitive on Sang medium compared to the Oregon flies but were able to use exogenous bases or nucleosides more efficiently.(ABSTRACT TRUNCATED AT 250 WORDS)

Aminopterin↗
PubMed1982

Part of the autonomous nervous system in the development of chaotic post-extrasystolic pictures. Electrophysiological and pharmacological studies of 49 cases.

The interpretation of post-extrasystolic parameters and their significance is discussed. Programmed extrastimulation according to Strauss was carried out in 49 cases, before and after atropine and propranolol administration. The result was a computable sinoauricular conduction time (SACT), a chaotic picture, or an ascending line without plateau. The patients were selected on basis of their intrinsic heart rates (IHR). If the total SACT exceeded 250 ms, the chaotic post-extrasystolic picture and the ascending 1st phase without plateau were considered pathologic, then after drug testing the ratio of pathologic parameters decreased from 54 to 22% in cases with normal IHR. Including cases with pathologic IHR the ratio increased from 55 to 90%, especially in asynchronous chaotic pictures. After drug testing the chaotic forms were always replaced by a plateau in cases with normal IHR, but in pathologic ones the chaotic picture appeared to be a dominant electrophysiological parameter. It follows that the autonomous nervous system has its part in the development of chaotic post-extrasystolic pictures. A plateau in the post-extrasystolic curve could mean a functional organization and synchronism rather than a conduction disturbance; to the latter a high-level plateau would correspond.

Atropine↗
PubMed1982

Synchronized and desynchronized sinus node activity.

In certain cases because of sinus arrhythmia and/or anarchic return and postreturn cycles caused by premature atrial stimulation, the sinoatrial conduction time cannot be calculated since a chaotic postextrasystolic pattern appears. We examined 49 patients with a history and ECG signs suggesting sinus node dysfunction by programmed extrastimulation method as proposed by Strauss et al. prior to and after pharmacologic autonomic blockade (with propranolol 0.2 mg/kg body weight and atropine sulfate 0.04 mg/kg intravenously). Patients with normal intrinsic heart rate (IHR) (n = 31) showed chaotic postextrasystolic responses in 38%, which in every case could be eliminated by autonomic blockade, resulting in a clear I and II phase with a well estimated intrinsic conduction time. Patients with pathologic IHR (n = 18) gave chaotic responses in 22% which after drug testing increased up to 72%. The chaotic postextrasystolic patterns are to be interpreted as the desynchronization of the sinus potentials, while plateau (phase II) as functional integrity, synchronized activity of the sinus node, dependent on the momentaneous balance of the autonomous tone, and on the integrity of the pacemaker cells. The desynchronized chaotic responses are considered on one hand as a dystonic neurovegetative electrophysiologic characteristic, on the other hand as a primary extrastimulation parameter of the intrinsic sinus node dysfunction.

Adult↗
PubMed1981

[Sinus node disease - diagnosis and treatment].

The concept of sinus node disease is defined by a group of clinical and electrocardiographic features related to sinus node dysfunction whatever its mechanism; the organicity of the disease can be proven if total or subtotal histological alterations of the sinus node are demonstrated. The most typical symptoms are neurological (syncopes and dizziness). Sinoatrial block, sinus arrest, sinus bradycardia or bradyarrhythmia, and the bradycardia-tachycardia syndrome are the most usual electrocardiographic aspects. The diagnosis is often rendered difficult by the usually intermittent and frequently nonspecific character of the symptoms and of the ECG signs. Holter monitoring is often essential to resolve these difficulties. If the diagnosis remains dubious, the use of electrophysiological methods is necessary: direct recording of the sinus nodal intracardiac potential can now be added to the classical rapid and premature atrial stimulation, possibly complemented by pharmacological tests. Finally, therapeutic indications can be considered after a correct clinical, electrocardiographical and electrophysiological evaluation of the patient. Medical treatment alone is usually ineffective in controlling the attacks of arrhythmia and the neurological episodes. If the sinus nodal dysfunction is obvious and symptomatic, permanent pacing is the treatment of choice. Its short and medium term results are generally excellent, while the long term results, especially with regard to survival of the patients, could be improved by the most recent pacing techniques.

Aged↗
PubMed1980

[Sinus node dysfunction. Clinical outcome and results of cardiac pacing].

112 patients (average age 66 +/- 13 years) with sinus node dysfunction, selected on clinical, electrocardiographic and electrophysiological criteria, were followed up for a period of 3 to 55 months (average: 30,2 months). Permanent cardiac pacing was instituted in 59 patients (52,6 p. 100), and the remaining patients treated medically. 25 patients were lost to follow up (22,3 p. 100: 5 paced, 20 non paced). 16 patients died (14,2 p. 100): mortality was relatively early (average 11,7 months) and higher in patients with pacemakers (15/16); the causes of death were acute heart failure (8 cases), and cerebral vascular accident (3 cases). In the surviving paced patients neurological symptoms completely regressed. In this series, the life expectancy of patients with sinus node dysfunction seemed to depend mainly on the state of their myocardium, but the functional prognosis was clearly improved by cardiac pacing.

Adolescent↗