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J M Richard

Publications and source records attributed to J M Richard.

At least 37 records · Page 2Linked to original sources
PubMed1990

[QSAR analysis of the toxicity of a series of pyridines related to the mushroom toxin orellanine: comparison of the results obtained with physico-chemical, steric and quantal parameters].

To complete a preceding work, we have made a QSAR study of a series of mono- or bi-pyridines, aminoxidized or not, wearing diverse substituents and related to the mushroom toxin orellanine. For the description of these molecules, we tried several sterical parameters which we have recently defined (sigma D and sigma S) or which we define here (D3) as well as physical and quantal parameters calculated with the CNDO/2 method, besides the parameter of hydrophobicity log P. Among the regression equations obtained, three have a correlation coefficient greater than 0.96, which is very high, taking into account the nature of the biological response (LD50). The importance of the hydrophobicity and of the size of the molecules in the expression of their toxicity is confirmed, as well as the particularity of orellanine in the series studied.

2,2'-Dipyridyl↗
PubMed1990

[Choice of methods for reconstruction of the cheek after carcinologic excision based on a retrospective study of 32 cases in 8 years from 1980 to 1987 at the Gustave Roussy Institute].

In this article, after reviewing the different possibilities for cheek reconstruction consecutive to carcinologic excision, we specify the choice method for closure, according to the anatomical type of substance loss incurred. In all cases, endobuccal skin covering is needed. --As regards small lesions, there is no such thing as "the" ideal flap. --As far as tegumental cheeks are concerned, the deltopectoral flap is the choice one. --In case of mucous reconstruction, submental flaps afford elegant solutions. --With large lesions, musculocutaneous flaps are best used. Lastly, it seems that the first surgical treatment (excision, curage and plasty) followed or not by radiotherapy, depending on anatomopathological findings, brings acceptable and prompt restoration of function and morphology.

Adult↗
PubMed1989

Multiple synchronous and metachronous cancers of the upper aerodigestive tract: a nine-year study.

This retrospective study was based on 9,089 patients and includes 855 cases (9.4%) of multiple primary cancers treated between 1975 and 1983. Three hundred fifty (42.1%) of these multiple cancers were considered synchronous, while 480 (57.9%) were classified as metachronous. Fifty percent of the metachronous cancers occurred within 31 months after the first primary; the mean time between the first primary and the second primary was 45 months. Approximately 22% of second primaries were found more than 5 years after the initial tumor. Five-year survival rates were higher in metachronous cancers (55%) than in synchronous cancers (18%). Survival rates varied according to the treatment. In 49.4% of synchronous tumors the treatment had to be modified because of the presence of two cancers. In these patients, 5-year survival rates were as low as 8%. In synchronous cancers that required no modification of the treatment, the prognosis was better and the survival rate was 28%. The preferential anatomical location of the second synchronous and metachronous cancers is discussed for first primaries situated in the oral cavity (103 cases), the oropharynx (120 cases), the hypopharynx (92 cases), and the larynx (87 cases). Second primaries in the esophagus were mostly synchronous cancers while, in the lung, second cancers were more frequently metachronous tumors.

Age Factors↗
PubMed1988

Nephrotoxicity of orellanine, a toxin from the mushroom Cortinarius orellanus.

Pure orellanine extracted from the mushroom Cortinarius orellanus is highly toxic in mice both when given intraperitoneally (LD50 = 12.5 mg/kg) or per os (LD50 = 90 mg/kg). The kidneys of mice injected i.p. with orellanine show similar tubular necrosis to that obtained with whole mushroom given per os. This demonstrates that orellanine is the true, principal toxin of C. orellanus. The similarity of the structures of the toxin and of bipyridinium herbicides such as methylviologen (paraquat) or the nephrotoxic diquat led other authors to presume a similar mechanism for orellanine toxicity. Our study of the electrochemical behaviour of orellanine shows that its mechanism of action has to be different from that of these poisons.

2,2'-Dipyridyl↗
PubMed1988

Interstitial and external radiotherapy in carcinoma of the soft palate and uvula.

Forty-three patients, all male, with limited epidermoid carcinoma of the soft palate and uvula were treated by interstitial implant usually associated with external radiotherapy. Most patients received 50 Gy external irradiation to the oropharynx and neck followed by 20-35 Gy by interstitial iridium-192 wires using either guide gutters or a plastic tube technique. Twelve primary tumors and two recurrences after external irradiation alone had implant only for 65-75 Gy. Total actuarial local control is 92% with no local failures in 34 T1 primary tumors. Only one serious complication was seen. Overall actuarial survival was 60% at 3 years and 37% at 5 years but cause-specific survivals were 81% and 64%. The leading cause of death was other aerodigestive cancer, with an actuarial rate of occurrence of 10% per year after treatment of a soft palate cancer. Interstitital brachytherapy alone or combined with external irradiation is safe, effective management for early carcinoma of the soft palate and uvula but second malignancy is a serious problem.

Actuarial Analysis↗
PubMed1988

Olfactory esthesioneuroma: a report of 40 cases.

Olfactory esthesioneuroma is a rare malignant tumor arising in the olfactory epithelium. Forty cases observed at the Institut Gustave-Roussy from 1956 to 1987 are reported. This tumor usually grows slowly and is usually local, but it is important to be aware of the possibility of lymph node involvement (17%) and, particularly, of rapid development of distant metastases (25%), usually within 6 months. CT scan, and more recently, NMR have proved to be of value in choosing the surgical approach. In view of the usual point of departure, a combined neurosurgical and transfacial approach seems to be a satisfactory approach for obtaining oncological control of the lesion. The role of chemotherapy is discussed. The main prognostic factors seem to be the size of the lesion, the intracranial extension, and the lymph node involvement.

Adult↗
PubMed1987

Phytotoxicity of orellanine, a mushroom toxin.

Orellanine, a toxic principle of Cortinarius orellanus Fr., efficiently inhibited the photosynthetic activity of duckweed, Lemna minor L., at a concentration of 0.4 mM. A lower concentration (0.06 mM) blocked the O2 production in isolated spinach class A chloroplasts. However, no effect was observed on thylakoids (class C chloroplasts), showing that orellanine does not interfere with the chloroplastic electron transfer chain and that orellanine does not act like methylviologen (paraquat) in green plants, as previously suggested. An electrochemical study of orellanine and related compounds showed that orellanine can neither be reduced by electrons derived from H2O nor from NADPH, as is methylviologen in plant and animal cells, respectively.

2,2'-Dipyridyl↗
PubMed1987

Combined treatment of cancer of the posterior oral cavity and oropharynx.

Ninety composite resections were carried out as primary treatment for a squamous carcinoma of the tonsillar region between 1970 and 1978. All patients have been followed-up for at least 3 years, except for 5 who have been lost to follow-up. All patients received postoperative radiotherapy (between 50 Gy and 65 Gy depending on the tumour resection status). Sixty-one patients received preoperative chemotherapy and 42% had clinical reduction of tumour size. The overall survival was 45.5% at 3 years and 43% at 5 years. Local recurrences were the most frequent oncological failure (25%). Tumours classed T3, insufficient tumour resection and lymph node invasion had poor prognostic value. We emphasize the necessity for primary surgery with preoperative chemotherapy and postoperative radiotherapy for squamous carcinoma of the posterior oral cavity and oropharynx.

Adult↗
PubMed1987

Prognostic factors in cervical lymph node metastasis in upper respiratory and digestive tract carcinomas: study of 1,713 cases during a 15-year period.

A prospective study of 1,713 patients with squamous cell carcinoma of the head and neck submitted to neck dissection between 1957 and 1973 is presented. We confirm the prognostic significance of the histological analysis of the nodal metastasis. Capsular rupture is the most important factor regardless of the primary site or tumor size. The presence of tumor emboli within lymphatics, the number of invaded nodes, and the number of nodes with capsular rupture are of significance though to a lesser extent. Classification of the clinical characteristics or the nodes provided, in 70% of the patients, a good prediction of histological involvement. In the clinical estimation of histological invasion, an important parameter is the size of the largest node detected, and we suggest this characteristic should be included in the TNM classification of UICC.

Carcinoma, Squamous Cell↗
PubMed1987

[Non-Hodgkin's malignant lymphomas of the nasopharynx. Apropos of 24 cases treated at the Institut Gustave-Roussy].

Twenty-four patients with non Hodgkin's lymphoma of nasopharynx were treated in the Institut Gustave-Roussy, France, between 1976 and 1983. Mean age of patients was 53 years and the male/female sex ratio was 2. Symptomatology was immediately suggestive of a lesion in the nasopharynx in 21 of the 24 patients, and histology gave an unfavorable prognosis (diffuse large cell tumors) in 71% of cases. Complete investigations showed the lymphoma to be relatively limited in extent in the majority of cases (68% of stages I and II). These findings are in agreement with published reports. The 4 patient with stage I disease were treated by irradiation alone and are all alive without recurrence after 43 months. The 11 patients with stage II lesions received combined chemo-radiotherapy, and at 42-month follow up 8 were alive without recurrence (1 patient died of intercurrent illness). Results of conventional chemotherapy (CHVmP) in patients with stages III and IV were disappointing, however: only one patient survived for 60 months (after a cerebral recurrence treated by irradiation). Although current therapy is effective for stage I and II lesions, patients with stages III and IV require more aggressive therapy recently developed: heavy multiple chemotherapy, and even intensive chemotherapy-total body irradiation and bone marrow graft.

Adult↗
PubMed1987

[Malignant neoplasms of the nasal cavity and paranasal sinuses. Analysis of 216 cases of malignant neoplasms of nasal cavity and paranasal sinuses].

This study is a retrospective analysis of 216 cases of malignant tumours of the nasal cavity and paranasal sinuses, treated from 1965 to 1980. The mean age at diagnosis was 59 years, 70 per cent were men and 30 per cent women. There were 121 (56%) epidermoid carcinomas, and 31 (14%) adenocarcinomas. Three-year and five-year actuarial survival rate was 40 and 33 per cent respectively for epidermoid carcinomas, 72 and 50 per cent respectively for adenocarcinomas. Recurrences occurred in 46 per cent of epidermoid carcinomas and 42 per cent of adenocarcinomas. Early diagnosis is important to improve the survival rate, and radical primary treatment should be carried out to reduce the rate of recurrence.

Adenocarcinoma↗
PubMed1987

[Functional surgery in cancer of the laryngeal vestibule. Apropos of 149 cases treated at the Institut Gustave-Roussy].

Functional surgery for treatment of 149 cases of cancer of vestibule of larynx admitted to the Institut Gustave-Roussy, Paris, included 92 supraglottic horizontal laryngectomies and 57 reconstructive subtotal laryngectomies with crico-hyoidopexy. General selection criteria for performing subtotal laryngectomy were very strict: local criteria included tumor of vestibule with possible extension to ventricle, to an arytenoid cartilage or to the HTE space, and regional criteria, more particularly, required absence of any palpable gland or mobile gland of less than 2.5 cm. This rigorous selection explains excellent carcinologic results: 90.8% survival after 5 years following subtotal laryngectomy as against 37.9% after supraglottic horizontal laryngectomy, equivalent to a survival rate for all cases of cancer of vestibule of larynx treated by functional surgery of 65% at 3 years and 58% at 5 years.

Adult↗
PubMed1986

Pharmacokinetics of intra-arterial and intravenous cisplatin in head and neck cancer patients.

After administration of cisplatin (50 mg/m2 on days 1 and 2) by intra-arterial or intravenous infusions over 1 or 6 hr to a total of 24 patients with head and neck cancer, the main pharmacokinetic parameters of platinum were determined according to a multicompartmental analysis. Elimination half-life of total platinum is greater than 3 days, the amount of platinum recovered in the urine over 7 days accounting for 15-50% of the administered dose. The half-life of filterable platinum species was calculated from the urinary excretion data: 39 +/- 17 min (i.a./1 hr), 37 +/- 24 min (i.a./6 hr), 58 +/- 17 min (i.v./1 hr) and 51 +/- 22 min (i.v./6 hr). Biopsies of the tumor were also analyzed on day 3 for their platinum content. The mean concentrations of platinum in biopsies were: 2.72 micrograms/g (i.a./1 hr), 3.89 micrograms/g (i.a./6 hr), 1.27 micrograms/g (i.v./1 hr) and 1.38 micrograms/g (i.v./6 hr). Tumor regression, based upon clinical and histological data, was only moderate after this single chemotherapy course.

Adult↗
PubMed1985

A quantitative structure-activity relationship study on substituted pyridines as a contribution to the knowledge of the toxic effects of orellanine, a toxin from the mushroom Cortinarius orellanus.

Quantitative structure-activity relationships are established based upon the toxicity of 21 substituted pyridines. They are used as a predictive tool to calculate the toxicity of orellanine, a toxin from the mushroom Cortinarius orellanus (Fries). The actual toxicity of orellanine is quite different from the values calculated based upon the postulated bipyridine structure. The exact structure of orellanine may be questioned. However, our results show that even slight variations of the substituents of pyridines may cause dramatic changes of toxicity.

2,2'-Dipyridyl↗