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G Chomette

Publications and source records attributed to G Chomette.

At least 73 records · Page 4Linked to original sources
PubMed1989

[Should mild acute rejection of a cardiac graft be treated?].

With no additional therapy, mild acute cardiac allograft rejection progresses in 30 per cent of the cases towards moderate rejection. Three hundred mild rejections which occurred in 120 patients between May 1987 and May 1989 were studied and divided into 3 groups according to their treatment. Group I rejections (n = 108) were left untreated. In group II rejections (n = 186), the dose of oral corticosteroid therapy was increased, and in group III rejections (n = 6) major immunosuppressive treatment with methylprednisolone and antilymphocyte globulins (or Orthoclone OKT3) were initiated in view of the clinical and echocardiographic severity of the rejection. In the untreated group, 20 per cent of mild rejection progressed to moderate rejection, while 67 per cent are still at a mild stage in control myocardial biopsies. In group II, only 5 per cent of mild rejections have become moderate, and 19 per cent persisted as mild in control biopsies (p less than 0.05). The treatment of group III rejections resulted in complete disappearance of signs of heart failure and improvement of right and left ventricular contractile functions, proving that severe rejection was cured. This study demonstrates the effectiveness of increased oral corticosteroid therapy in minimal acute cardiac allograft rejections, without significant increase in infection or mortality rate. The principal reason for treating mild acute cardiac allograft rejections is to prevent their progression towards moderate rejections which require major immunosuppressive treatments and therefore have higher post-transplantation infection and mortality rates.

Adrenal Cortex Hormones↗
PubMed1989

A morphometric study of the lumbar foramen. Influence of flexion-extension movements and of isolated disc collapse.

The authors undertook a morphometric study of the intervertebral foramina in anatomic specimens of spines unaffected by degenerative lesions. They studied the variations in shape and size of 38 intervertebral foramina during flexion-extension movements and following an isolated disc collapse. The cast technique takes into account the bony prominences, the bulge of the disc anteriorly and of the capsulo-ligamentous structures posteriorly. In flexion, all the diameters of the foramina are maximal. In full extension all the diameters decrease significantly: the pedicles come closer together, the disc bulges posteriorly and the ligamentum flavum is pushed forward by the superior articular process of the underlying vertebra. A disc collapse of 4 mm decreases all the diameters, and in this case lumbar extension results in a sufficient decrease of foraminal diameter to threaten the nerve root.

Female↗
PubMed1989

Autoradiographic localization of sigma opioid receptors in the gastrointestinal tract of the guinea pig.

The distribution of sigma and phencyclindine binding sites in the gastrointestinal tract of the guinea pig was studied by autoradiography after in vitro incubation of tissue slices with (+)3H-SKF 10,047 and 3H-1-1-[(2-thienyl)cyclohexyl] piperidine to locate sigma and phencyclidine receptors, respectively. A dense distribution of sigma binding sites was observed in the mucosa and in the submucosal plexus, particularly at the level of the fundus and duodenum. Muscular layers were only marginally labeled. No phencyclidine binding site could be demonstrated in any area. This selective distribution suggests a functional role of sigma receptors mainly in the control of endocrine or exocrine secretions, or both.

Animals↗
PubMed1989

Relationship of histological subtypes to prognosis in early stage Hodgkin's disease: a review of 312 cases in a controlled clinical trial. The Groupe Pierre et Marie Curie.

To assess the prognostic significance of a newer histologic classification of Hodgkin's disease (HD), microscope slides from the time of diagnosis of 312 clinical stage IA or B, IIA or B and IIIA patients were reviewed in 1987, 6-10 years after their participation in a radiochemotherapeutic trial (1976-1982). Overall, the diagnostic reproducibility of the Rye classification by the same pathologist was confirmed. However, a new analysis showed an improvement in the differential diagnosis between HD and non-Hodgkin's lymphomas (NHL) by the identification of 24 NHL (8%) amongst the patients originally diagnosed as HD. Most of the NHL identified on review had been classified originally as mixed cellularity. On review, none of the new histological subtypes of HD was significant for prognosis of relapse-free survival or overall survival. Only identification of NHL was shown to have an independent prognostic value on relapse rate (P = 0.012) and on overall survival (P = 0.10). It is concluded that diagnosis of HD by itself remains, in 1988, the sole histologic factor influencing the prognosis of these patients.

Adolescent↗
PubMed1989

Electrode catheter ablation of resistant ventricular tachycardia in arrhythmogenic right ventricular dysplasia: experience of 13 patients with a mean follow-up of 45 months.

Electrode catheter ablation (fulguration) is a new technique for the treatment of ventricular tachycardia resistant to medical treatment. It proved effective in our hands in a series of 65 cases of ventricular tachycardia of varied origin. This paper reports the early results in a subgroup of 13 patients suffering from arrhythmogenic right ventricular dysplasia in whom shocks ranging from 160 to 280J, single or multiple, in one or up to three sessions were delivered. In the 11 patients surviving the DC ablation procedure single or multiple monomorphic sustained VT was brought under control. However, four patients (36%) required therapeutic antiarrhythmic treatment following the fulguration therapy. During the learning phase one case of death was related to poor catheter selection and the other to poor protocol. The post-mortem study of the effect of shocks depends on the anatomical structure to which the shocks have been delivered.

Adult↗
PubMed1989

[Pleomorphic adenoma of the salivary glands. Impact of the myxoid component on the prognosis].

In a series of 570 pleomorphic adenomas of main and accessory salivary glands, we found 48 recurrences (8.04%). These recurrences occurred between several months and 19 years after surgical treatment. They were more frequently noted in parotid tumors. Comparatively to a control series, in recurrent tumors myxoid structures were more frequent than epithelial structures, as demonstrated by immuno-markings (anti-protein S 100 and anti-vimentin sera). Besides, in these tumors, extracapsular myxoid expansions were commonly seen. The proliferative potential of myoepithelial cells which are the main cellular component of myxoid areas, is thus suggested as a mainly factor of recurrence of pleomorphic adenomas.

Adenoma, Pleomorphic↗
PubMed1989

[Facial circumscribed ossifying myositis. Anatomo-clinical and tomodensitometric study].

1 case of circumscribed myositis ossificans of the temporal muscle is reported in a 21 years-old man. The initial complaint was a sudden non traumatic swelling. Roentgenography showed a characteristic feature: peripheral radio-opacity around a non-opacified area. Under microscope, we could find 3 zones: a central fibroblastic area, an intermediate zone with immature osteoid bone, a peripheral zone with mature lamellar bone. In addition, we used histoenzymological and electron microscopical methods. The difficulties of diagnosis, the pathogenesis and the prognosis of this disease were also discussed.

Adult↗
PubMed1989

[Causes of sudden death in athletes].

Sudden death is rare in athletes, and it is only in recent years that significant series were collected, making it possible to draw the cardiological profile of athletes who died suddenly at the peak of exertion or while recovering. A study of the literature, both medical and paramedical, has yielded 53 cases in which the most frequent causes of sudden death were hypertrophic cardiomyopathy (26 p. 100), (arrhythmogenic right ventricular disease (19 p. 100), congenital abnormalities of coronary arteries (11 p. 100) and coronary atheromatous lesions (9 p. 100), to which must be added various other causes. This study clearly demonstrates the hitherto unrecognized importance of arrhythmogenic right ventricular dysplasia-a condition which, as recent data suggest, is not solely due to a myocardial development disorder but also to an infective disease, an acute of chronic myocarditis. In subjects with this condition, new exploratory methods might detect the presence of an arrhythmogenic substrate during medical screening of athletes, but in any case these causes of sudden death suggest that a fast rhythm disorder was involved in several of these deaths. This disorder could be treated if the attendants were trained to carry out cardiorespiratory resuscitation procedures or if they had access to a defibrillator which should be available on every sports field.

Adult↗
PubMed1989

[Tissue effects of the CO2 laser in stomatologic surgery].

This preliminary study included 30 skin and oral mucosa biopsies sampled various time intervals after CO2 laser incision. Samples taken after scalpel incision served as controls. During the first stages of healing, earlier fibroblast stimulation following laser incision was demonstrated by histoenzymologic and electron microscopy findings. Further more, immunohistochemical studies showed more significant, although slightly delayed, production of collagen III and fibronectin. Our findings are consistent with the very good quality of most scars obtained after laser surgery.

Biopsy↗
PubMed1989

[Implants of fired ceramics in the dog. Preliminary study. Morphology of bone coaptation after 3 and 7 months].

An experimental study of biocompatibility for ceramic material was undertaken in dogs. We used 8 implants and 1 filling-up material in the alveolar bone. A regular radiographic control of the good coaptation and tolerance of these implants was done after various intervals. The sacrifice was performed at 3 and 7 months after the implantation. The good coaptation between alveolar bone and implant was demonstrated by means of different morphological methods. Thus, microradiographs of anatomical specimens, routine histological study following decalcification, analysis of some specimens without decalcification showed the tight coaptation between implant and alveolar bone, without any foreign-body granuloma or allergic reaction. Besides, by transmission and scanning electron microscopy, we could identify the various types of cells (macrophages, fibroblasts and osteoblasts) noted at the interface of the implant matrix at various intervals after the operation. By histoenzymological methods, we also tested the functional activity of these cells, peculiarly their possible osteogenic ability (alkaline phosphatase and ATPase highly positives in some of these cells).

Adaptation, Physiological↗
PubMed1989

[Criteria for choosing an endosseous implant. Clinical and fundamental results concerning sintered ceramic implants].

In our opinion, the primary criteria are: absence of severe residual lesions in case of failure of the implant, implant material with demonstrated biocompatibility and which does not interfere with modern medical imaging techniques (CAT-scan, NMRI); ceramics meet this criteria, an implant morphology allowing for perfect initial stabilization, sparing of tissue and good distribution of transmitted forces to bone, an easy, accurate and nontraumatic implantation technique, the possibility of connecting the implant to fixed or movable structures by precision prefabricated accessories, dismantlable if possible, convincing animal experiments and clinical results in large series with a follow-up of more than 10 years.

Animals↗
PubMed1989

[Central reparative giant cell granuloma of the jaw. Morphological study].

8 cases of central giant cell reparative granuloma of the jaws were morphologically studied. If the histological feature of this disease is theoretically characteristic (giant cells, fusiform cells, numerous vessels and more or less active osteogenesis) in fact other giant cells lesions, especially true giant cell tumors, often set a problem to the pathologist. In addition, the etiopathogenesis of that granuloma is discussed by means of the results of immunohistochemical, histoenzymological and ultrastructural findings.

Adolescent↗
PubMed1989

[Cystic lymphoid hyperplasia of the parotid in relation to acquired immunodeficiency syndrome (HIV+). Apropos of 2 cases].

Cystic lymphoid hyperplasia of the parotid, a rare disease, was recently described in patients with acquired immunodeficiency syndrome. We reported here 2 new cases of this illness. The 2 HIV+ patients showed an enlargement of parotid gland. A superficial parotidectomy was performed. The histological and immunohistochemical studies were completed in one case by a histoenzymological and ultrastructural study. We could see numerous cystic cavities lined with a cylindrical or metaplastic malpighian epithelium and surrounded by a lymphoid tissue, similar to a true lymph node with germinal centers. In these lymphoid structures, we could find some epithelial remnants and numerous epimyoepithelial islands. Besides, anomalies similar to those described in persistent generalized lymphadenopathies were obvious: hyperplastic germinal centers with multiplication of B lymphocytes and thin mantle zone, perifollicular hypervascularization, numerous macrophages, plasmocytes and T lymphocytes with increase of T8 cytotoxic subset in interfollicular and paracortical areas. An early opportunist infection is suggested in the histogenesis of this disease.

Acquired Immunodeficiency Syndrome↗
PubMed1989

[Intraepithelial neoplasm of the uterine cervix and angiogenesis: morphologic study].

Thirty uterine cervix specimens sampled following conization or total hysterectomy were studied using histology, histoenzymology (vessel phosphatase alkaline activity), and immunohistochemistry (demonstration of laminin and type IV collagen in epithelium and vessel basement membranes). Pathologic conditions included dystrophia, moderate dysplasia, severe dysplasia, and intraepithelial carcinoma. Results were compared to findings in a control group. We found that the severity of vascular abnormalities correlated positively with the severity of histologic epithelial lesions; this finding is consistent with colposcopic results. Anarchic angiogenesis with large, moniliform, tortuous vessels was seen in severe dysplasias and carcinomas. The vascular anomalies seem to precede the development of histologic lesions in some instances. Histogenesis of the abnormal vessels may involve production of an angiogenic factor by the cancerized epithelia.

Cervix Uteri↗
PubMed1989

[Cystic hamartoma of the mandibular angle. Apropos of a case].

A large cyst of mandibular angle was surgically removed in a 20 years-old woman. This cyst was discovered during childhood and was associated with a branchial para-mandibular cyst. It was histologically lined either with a malpighian epithelium with sebaceous islands or with a ciliated cylindrical epithelium. Because of its topography, its association with a branchial cyst and its histological feature quite similar to that of a cyst of thyroglossal duct, this cyst was thought to represent a simplified salivary ectopy composed only of a cystic secretory duct without any salivary parenchyma.

Adult↗
PubMed1989

[Undifferentiated epithelioma of the parotid and cystadenolymphoma. Apropos of a case].

A case of undifferentiated epithelioma of the left parotid gland occurred 2 years after the removal of a cystadenolymphoma in the right parotid gland. The relationship of these two tumours was supported by several statements: the immunohistochemical study demonstrated in the epithelial cells of the 2 neoplasms the existence of ACE, usually thought as characteristic of cystadenolymphoma. Besides, it showed a high number of plasma cells secreting IgA in the stroma of the 2 tumours, the ultrastructural study performed on the epithelioma also demonstrated some similarities between epitheliomatous cells and epithelial cells of cystadenolymphomas (outlined epidermoid or glandular differentiation, numerous mitochondria). A peculiar, perhaps immunological mechanism could induce the cancerization, according to the theories used to explain the histogenesis of cystadenolymphoma.

Adenolymphoma↗
PubMed1988

Cherubism. Histo-enzymological and ultrastructural study.

The 3 cases of cherubism reported affected the mandible. They were all studied by means of histo-enzymological and ultrastructural methods. This study demonstrated 3 stages in the morphological evolution of the disease, corroborated by clinical data. The 1st stage was characterized by an osteolytic granuloma with round, fusiform and giant-cells and a high level of activity of acid phosphatase. The 2nd stage showed repair with proliferation of highly active fibroblasts (increase in activity of leucine aminopeptidase). The 3rd stage exhibited an osteogenesis with high activity of alkaline phosphatase and ATPase. The pathogenesis of this rare osteodysplasia is discussed.

Adolescent↗