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Biomedical subjects

J Fenton

Publications and source records attributed to J Fenton.

At least 37 records · Page 2Linked to original sources
PubMed1993

Age as prognostic factor in premenopausal breast carcinoma.

Whether or not young age at diagnosis is an adverse prognostic factor in breast cancer has long been controversial, in part because much previous work has not taken due account of menopausal status and confounding factors. We have analysed the influence of age on prognosis in a consecutive series of 1703 patients with stage I-III breast cancer. All were premenopausal and all were treated in one centre (Institut Curie, Paris) between 1981 and 1985. Mean age was 44 years (range 23-55) and median follow-up was 82 months. Younger patients had significantly lower survival rates and higher local and distant relapse rates than older patients. The hazard rate of relapse decreased over time in the youngest age group (< or = 33) to reach that of older patients after 5 years. The relation between the hazard of recurrence and age was a continuous one, best fitted by a log-linear function and indicating a 4% decrease in recurrence for every year of age. Multivariate analysis of both survival and disease-free interval demonstrated that the worse prognosis of young age was independent of other factors such as clinical tumour size, clinical node status, histological grade, hormone receptor status, locoregional treatment procedure, and adjuvant systemic therapy. This difference in outlook has yet to be explained biologically but it does suggest the need for a closer look at the natural history of breast cancer in young women.

Adult↗
PubMed1993

Blunt cardiac trauma: survival after bichamber rupture.

Rupture of cardiac chambers after nonpenetrating blunt thoracic trauma is being recognized with increasing frequency. Despite a high mortality rate, survival after repair of a single-chamber rupture is widely reported. Bichamber cardiac rupture is less frequent, and we report a patient who survived this injury.

Adult↗
PubMed1991

Abnormal M-wave responses during exercise in myotonic muscular dystrophy: a Na(+)--K+ pump defect?

Maximum M-waves (muscle compound action potentials) were studied in the abductor pollicis brevis (APB), extensor digitorum brevis (EDB), and tibialis anterior (TA) muscles of 12 patients with myotonic muscular dystrophy (MMD) and in the same number of control subjects, matched for age and sex. The peak-to-peak amplitudes and voltage-time areas of the responses were measured at rest, between 40 maximum voluntary contractions (each lasting 3 s) and also during a 2-min recovery period. In 34 of the 36 control muscles the M-waves potentiated during the period of intermittent voluntary contractions. In the MMD patients, however, the M waves exhibited initial declines in 25 of 30 muscles. In the APB and EDB muscles the normalized mean values for the smallest M-waves, recorded during the 350 s total observation periods, differed significantly between the 2 groups of subjects. It is suggested that the sarcolemmal Na(+)-K+ pump has a raised threshold for activation in MMD patients.

Adult↗
PubMed1991

Endogenous platelet fibrinogen surface expression on activated platelets.

Intracellular platelet fibrinogen surface expression was studied in arabinogalactan-purified, resting, and thrombin-stimulated platelets. Platelet fibrinogen is derived from endocytosis of plasma fibrinogen by megakaryocytes. Like a variety of other adhesive proteins, it is stored in the platelet alpha-granule. Platelet fibrinogen surface expression was studied by using the antigen-binding fragments of a murine monoclonal antibody to platelet fibrinogen, F26, and an immunopurified polyclonal antifibrinogen antibody. Studies correlating platelet fibrinogen surface expression with the presence of the glycoprotein IIb-IIIa (GPIIb-IIIa) complex showed that in the presence of ethylene glycol tetraacetic acid (EGTA) at 37 degrees C, neither the GPIIb-IIIa complex nor platelet fibrinogen was expressed on the surface of thrombin-activated platelets. Similar experiments performed in the presence of EGTA and calcium showed proportional expression of the GPIIb-IIIa complex and platelet fibrinogen. The addition of Arg-Gly-Asp-Ser-containing peptides, the pentadecapeptide of the fibrinogen gamma-chain carboxy terminus, or the monoclonal antibody 10E5, when directed against the GPIIb-IIIa complex before thrombin activation, inhibited 65% to 94% of the platelet fibrinogen expression, as determined with the polyclonal and monoclonal antigen-binding fragments. When these same inhibitory agents were added immediately after or 5 minutes after thrombin, the amount of inhibition decreased significantly. Similar studies with a washed platelet system revealed that when the inhibitors of platelet fibrinogen expression were added before thrombin stimulation, the degree of inhibition observed was only 24% to 38%. This suggests that the major portion of platelet fibrinogen expression involves the release of platelet fibrinogen and its subsequent binding to GPIIb-IIIa. This binding may occur within the open canalicular system or on the platelet surface; in either case, wherever the site of released platelet fibrinogen binding occurs, it can be markedly inhibited by the RGD-containing peptides and the gamma-chain fibrinogen peptides. Approximately 10% to 30% of platelet fibrinogen may be expressed prebound to a platelet receptor, or else it is released and binds to a platelet receptor other than the GPIIb-IIIa complex.

Amino Acid Sequence↗
PubMed1991

Thrombin-induced leukopenia and thrombocytopenia are attenuated by PAF antagonist WEB 2086.

Thrombin has been shown to increase pulmonary transvascular permeability in vivo. This permeability change appears to be dependent on polymorphonuclear leukocytes (PMNs). In vitro, thrombin has been demonstrated to increase PMN adherence to endothelial cells coincident with generation of platelet activating factor (PAF) by endothelial cells. These observations have led to the suggestion that PAF mediates, in part, the attachment of PMNs to endothelial cells. We examined this hypothesis in vivo and in vitro with a specific PAF receptor antagonist, WEB 2086. Prior infusion of WEB 2086 into conscious sheep significantly attenuated the drop in peripheral blood PMN counts observed during and after infusion of alpha-thrombin (30 NIH U/kg). These data suggest that WEB 2086 prevented PMN margination on endothelial cells. WEB 2086 also attenuated the thrombocytopenia seen after thrombin infusion and ameliorated the thrombin-induced hypoxemia and hemoconcentration. WEB 2086 did not affect the thrombin-induced hemodynamic response, the degree of intravascular coagulation as assessed by fibrin degradation product generation, or thromboxane B2 generation. In vitro, WEB 2086 prevented the augmented adherence of sheep PMNs to sheep endothelial cell monolayers after thrombin stimulation. The results of the present study are consistent with the hypothesis that PAF mediates, at least in part, thrombin-induced leukopenia and thrombocytopenia in vivo.

Animals↗
PubMed1990

[Local recurrence of rectal cancers. Multidimensional analysis by anatomoclinical factors and role of irradiation].

Pre- or postoperative radiation therapy reduces the incidence of local recurrence after surgical treatment of rectal carcinoma. Factors related to local recurrence were analyzed retrospectively by uni- and multivariate analysis. One hundred and fifty-five patients (mean age: 65 years) were operated on with curative intent between 1967 and 1984. Ninety-four patients (46 patients having abdominoperineal resections (APR), and 48 having anterior resections) did not receive radiation therapy. Sixty-one patients had preoperative radiation therapy followed by APR in 59 cases. Univariate analysis showed that the risk of local recurrence increased significantly with male sex (p less than 0.006), positive lymph nodes (p less than 0.01), vascular invasion (p less than 0.02), and Astler-Coller classification (p less than 0.05). Tumor located at less than 5 cm from the anal verge was significantly related to recurrence only in patients not receiving radiation therapy (p less than 0.02). Multivariate analysis including therapeutic modalities showed that local recurrence was significantly related with male sex (p less than 0.02), positive lymph nodes (p less than 0.01), and distance to anal verge (p less than 0.01). The beneficial role of radiation therapy appeared only for tumors located 5 cm or less from the anal verge. Prognostic scores were established using these variables and the effect of irradiation was evaluated according to these scores. Radiation therapy significatively reduced the risk of local recurrence in low-risk patients, i.e., female with low-lying tumor and with negative lymph nodes (p less than 0.03).(ABSTRACT TRUNCATED AT 250 WORDS)

Adenocarcinoma↗
PubMed1990

[Invasive cancer of the uterine cervix in young women: retrospective study of 236 cases].

The study of cases treated between 1970 and 1984 at the Institut Curie, in women aged 40 years and under, was undertaken in order to determine the influence of age on prognosis. The incidence of these cases was stable throughout the 15 years study period as was the very high incidence of earlier cases: 84.5%. Earlier cases were treated with combined radiotherapy and surgery and advanced cases with radiotherapy alone. Overall survival rate was 75% at 5 years, 60% at 10 and 15 years: but 85% for the 36-40 years of age group, 74% for the 30-35 years of age group and 67% for women aged 29 and less. Five year survival rate for operated cases is the same for the 36-40 age group as for all age patients, according to the lymph node status. In contrast, it was 85% in the N-younger group, and 30% for those patients with lymph node involvement. In conclusion, from our study it appears that the overall survival rate for women of 36 years and less, and mainly 29 years and less, is significantly lower than that for older women, and that their prognosis is especially poor in the case of lymph node involvement.

Adenocarcinoma↗
PubMed1989

M wave potentiation during and after muscle activity.

The M wave (muscle compound action potential) has been shown to enlarge between successive 3-s voluntary contractions of the human thenar and extensor digitorum brevis (EDB) muscles. The changes, which affected both the amplitude and the area of the M wave, were more obvious in the thenar than in the EDB muscles. In the thenar muscles the mean amplitude was already significantly enlarged after the first voluntary contraction and close to the maximal value by the third (mean maximal increase 23.6 +/- 12.6% of control). The increase in mean M wave area was more gradual, reaching a maximum of 29.3 +/- 14.1% at 100 s. After the voluntary thenar contractions ceased, the amplitude of the M wave subsided more rapidly than the area and had regained the control value within 50 s. The magnitude and time course of the increase in EDB M wave area (maximum change 25.9 +/- 15.2%) were similar to those of the thenar muscles; however, the subsequent decline was slower. The amplitude of the EDB M wave showed the least change, and the maximum increase (11.4 +/- 9.6%) occurred early in the postcontraction period. In both muscles the changes in M wave amplitude and area were significantly different from the control values.

Action Potentials↗
PubMed1989

[2 cases of testicular seminoma associated with HIV infection. Analysis of treatment tolerance].

Two homosexuals with advanced HIV infection and testicular seminoma stage IIb and IIc were treated with irradiation associated with chemotherapy in one patient. Subdiaphragmatic irradiation was followed by moderate diarrhoea. Initial chemotherapy consisted of cisplatinum, vinblastine, bleomycin replaced by cyclophosphamide after radiotherapy. The use of cyclophosphamide was discontinued after 2 courses due to neutropenia (less than 1500/mm3). Complete tumor remission was achieved in both patients without infection in spite of an aggravation of the CD4 deficit (5/mm3, 52/mm3). The patients died of opportunistic infections 14 and 12 months after terminating treatment. We conclude that cytotoxic and radiation treatment can be administered safely if carefully monitored in these severely immunodepressed patients.

Adult↗
PubMed1989

[Vaginal cancer: primary invasive squamous cell carcinoma in adults].

Retrospective study of 80 cases treated at the Institute Curie from 1969 to 1982. This cancer is rare; it is generally seen in old women, mostly arising in the upper third. The treatment is exclusive radiation therapy in almost all the cases, through four pelvic fields up to a dose of 45/50 Gy. A boost dose is added with a perineal field, or curietherapy. Immediate tolerance is rather good and late severe complications are rare (6%). The 5-year survival rate is 52%. The prognostic factors, according to the Cox model, are: the clinical T stage (5-year survival rate of 66% in T1-T2 stages, and 30% in T3-T4 stages), the patient's age (5-year survival rate of 65% for the patients less than 70 years of age, 40% for the older ones), complete tumor regression 3 months after the end of the treatment (5-year survival rate of 71% for those patients, and only 12 months of median survival for the others who are all dead at 36 months).

Adult↗
PubMed1988

Implantation of cultured thymic fragments in congenitally athymic (nude) rats. Ultrastructural characteristics of the developing microenvironment.

Cultured thymic fragments correspond to the thymic microenvironment depleted of lymphocytes and dendritic cells. When these fragments are implanted under the kidney capsule of congenitally athymic rats, lymphocytes and dendritic cells of host origin enter the graft and induce thymus-dependent immunity in the recipient. This paper describes the ultrastructure of the fragments and the changes that occur during the restoration of normal thymic architecture. At the end of the culture period of 6-9 days and in the early stages after implantation, the grafts consist of keratin-containing epithelial cells of unusual morphology that can be labelled with antibodies raised against the epithelium of the mid/deep cortex and the subcapsule/medulla. Normal thymic architecture develops, including nerves and blood vessels, as lymphocytes populate the environment, and by 4-6 weeks the epithelial cells are the same phenotypically and ultrastructurally as those found in normal rat thymus. However, some areas without lymphocytes still contain the atypical epithelial cells seen before implantation. Large multinucleated giant cells are also present with a few associated epithelial cells of subcapsular/medullary phenotype. In conclusion, the cultured thymic fragments contain a hitherto unknown precursor epithelial cell with an atypical ultrastructure and phenotype that is not seen in normal development.

Animals↗
PubMed1988

Anal margin carcinoma: 21 cases treated at the Institut Curie by exclusive conservative radiotherapy.

Between 1962 and 1980, 21 patients with anal margin carcinoma were treated with exclusive radiotherapy. They were divided into 4 T1, 7 T2, 8 T3 and 2 T4 cases; only 3 cases presented with an N1 lymph node involvement (1 T2 and 2 T3). The tumor dose was 65 Gy in 22 fractions and 55 days; the inguinal dose was 50 Gy in 15 sessions and 50 days for prophylactic irradiation performed in 9/18 N0 patients, and 65 Gy with a limited 15 Gy boost for the 3 N1 cases. The results are: for T1, 4 patients alive and well out of 4; for T2, 3 out of 7; for T3, 2 out of 8; for T4, 2 out of 2. The overall survival was 11 out of 21 after 5 years. Severe complications occurred in 2 patients out of 21. Sphincter preservation was obtained in 9 patients out of 10 cured cases.

Aged↗
PubMed1988

Feasibility study of an alternating schedule of radiotherapy and chemotherapy in advanced uterine cervical carcinoma.

From July 1981 to April 1982, 36 patients with advanced cervical carcinoma stage III (24 patients) and stage IV (12 patients) entered a feasibility study of a radiotherapy and chemotherapy combination. The first three chemotherapy courses consisted of cis-platinum alone (50 mg/m2) and were interdigitated with radiotherapy. Six more courses composed of an association of cis-platinum (50 mg/m2) and cyclophosphamide (400 mg/m2) were given after the completion of radiotherapy. Radiotherapy was delivered in two courses of 25 Gy separated by a gap of 2 weeks. The overall 4-year survival rate was 35% (95% CI: 22%). The 4-year survival rate, cumulative loco-regional failure rate, and cumulative metastasis rate were respectively 44% (95% CI: 20%), 56% (95% CI: 21%), and 30% (95% CI: 21%) in stage III and 28% (95% CI: 27%), 83% (95% CI: 21%) and 74% (95% CI: 30%) in stage IV. The incidence of immediate and late complications was low: no patient had her radiotherapy stopped because of an intolerance and two patients had their chemotherapy stopped because of an haematological intolerance. Only one patient presented a severe late clinical complication (small bowel injury).

Adult↗
PubMed1988

Is prophylactic para-aortic irradiation worthwhile in the treatment of advanced cervical carcinoma? Results of a controlled clinical trial of the EORTC radiotherapy group.

From November 1977 to July 1981, 441 patients with cervical carcinoma were randomized between pelvic irradiation and pelvic and para-aortic irradiation. Included were patients with stage I and IIB with proximal vaginal and/or parametrial involvement with positive pelvic lymph nodes either on lymphangiogram or at surgery, and stage IIB with distal vaginal and/or parametrial involvement and III regardless of pelvic node status on lymphangiogram. Patients with clinically or surgically involved para-aortic nodes were not included. The external beam dose to the para-aortic area was fixed at 45 Gy. There was no statistically significant difference between the two treatment arms in terms of local control, overall distant metastases and survival with no evidence of disease (NED), although the incidence of para-aortic metastases and distant metastases without tumor at pelvic sites was significantly higher in patients receiving pelvic irradiation alone (pelvic group). The 4-year NED survival rate was 51%. The incidence of severe digestive complications was significantly higher in patients receiving para-aortic irradiation (para-aortic group). Routine para-aortic irradiation for all high risk patients with cervical carcinoma is of limited value, but patients with a high probability of local control can benefit from extended field irradiation, despite an increase in severe digestive complications.

Aorta↗
PubMed1988

[Colloid cancers of the breast. Value of radiotherapy. A series of 138 cases treated at the Curie Institute].

A series of 138 mucinous breast carcinomas was treated at the Institut Curie from 1970 to 1980: 107 were diagnosed as "pure" mucinous carcinoma and 31 as "mixed" mucinous carcinomas. Fifty per cent of the cases were stage T2 and 78% N0-N1a. Treatment methods were radical mastectomy in 113 cases (82%) with pre-operative irradiation for 37 patients and post-operative irradiation for 14 patients. A conservative treatment was used for 25 patients, consisting either of lumpectomy followed by radiotherapy (in 15 cases) or radiotherapy alone (in 10 cases). The five-year actuarial survival rate was 81% for the "pure" group and 87% for the "mixed" group; it was 70 and 75%, respectively, at ten years follow-up. In this series, survival was not influenced by the type of treatment. The efficacy of radiotherapy was evaluated from the local recurrence rate: only four local failures among the 25 conservative treatments were noted. Our conclusion is that radiotherapy, with or without lumpectomy, is efficient in mucinous breast carcinoma and could be useful in selected cases.

Actuarial Analysis↗