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P Colin

Publications and source records attributed to P Colin.

At least 91 records · Page 5Linked to original sources
PubMed1989

Conventional megavoltage radiotherapy in the management of malignant epithelial tumours of the parotid gland.

This is an evaluation of definitive conventional megavoltage radiotherapy in a consecutive series of 35 patients presenting malignant epithelial tumours of the parotid gland. In this series, the 5-year actuarial locoregional control rate was 41% with a 5-year crude survival rate of 36%. The results are analyzed according to tumour presentation and tumour doses. Six of 15 patients with tumours larger than 6 cm have had a lasting locoregional control. During the same period 43 other patients received radiotherapy as a post-operative modality. Results obtained in this group confirm the previously published data. While recent studies tend to demonstrate the specific efficacy of high LET radiation in the management of locally advanced salivary gland tumours, radical conventional radiotherapy can still be employed with a curative intent when neutron facilities are not available.

Adult↗
PubMed1989

Rapid identification of Salmonella from poultry meat products by using 'Mucap Test'.

A study was made in order to improve a new Salmonella identification test (Mucap Test) in which umbelliferone is released, giving a blue fluorescent light under a Wood lamp, after contact with Salmonella colonies. The study concerned 354 colonies, previously isolated from 55 poultry meat samples. Two enrichment media [Tetrathionate Bile Broth (TBB) and Rappaport Vassiliadis (RV)] and two isolation media [Brilliant Green Agar (BGA) and Desoxycholate Agar (DA)] were used, and the results of the test obtained respectively with each association were compared. The sensitivity was consistently good, but the specificity of the test was generally poor. The best association seemed to be RV/DA which gave 85% specificity, against 39% for TBB/BGA, 58% for TBB/DA, and 77% for RV/BGA. The predominant genera responsible for false-positive results were Pseudomonas and Proteus Providencia.

Animals↗
PubMed1989

Treatment of cutaneous candidosis in guinea pigs: effect of zinc oxide on the antifungal efficacy of nystatin.

This article describes the in vivo evaluation of a new topical preparation (Zincostatin) indicated for Candida albicans infected diaper rash. In order to study the influence of the 20% zinc oxide (W/W) (a protectant) on the anti-candidal efficacy of the 100,000 U/g of nystatin found in the ointment, groups of guinea pigs received different treatments with or without local occlusion. Zinc oxide, nystatin, or the combination of both were applied, in the ointment base, on the backs of the animals inoculated with a fresh strain of Candida albicans. Macroscopic and microbiological evaluation of the skin lesions were assessed at regular intervals during 21 days. While the two treatments containing nystatin were more effective than zinc oxide alone, the latter agent did not decrease the efficacy of the antifungal drug in combination therapy. Also, zinc oxide seemed to afford some protection against local maceration induced by occlusion, which increased the severity of the infection.

Animals↗
PubMed1987

Rapid high-performance liquid chromatographic assay of acetaminophen in serum and tissue homogenates.

The quantitation of a hepatorenal toxic drug, acetaminophen, in blood and target organ tissues is needed for toxicokinetic and distribution studies. A rapid, sensitive and simple method is described to assay acetaminophen in rat serum and liver or kidney homogenates by reversed-phase high-performance liquid chromatography, using an octadecyl (3 micron particle size) Apex column, a mobile phase consisting of a mixture of distilled water-acetonitrile (86:14) and ultraviolet detection at 245 nm. Short retention times of ca. 3.75 and 6.25 min are observed for acetaminophen and the internal standard (sulfamerazine), respectively. A sensitivity of 50 ng/ml is easily achieved for 100-microliter serum and liver or kidney homogenate samples. The proposed method proved to have satisfactory recovery, precision and accuracy. The preliminary results obtained with human plasma of volunteers and of patients treated with various drugs show that the assay, with a sensitivity of 25 ng/ml, would be of considerable interest in clinical monitoring of acetaminophen.

Acetaminophen↗
PubMed1986

Simultaneous determination of the major metabolites of styrene and acetaminophen, and of unchanged acetaminophen in urine by ion-pairing high-performance liquid chromatography.

An improved isocratic high-performance liquid chromatographic method for the quantitative determination of the major urinary metabolites of styrene in urine is described. The high separation efficiency of an ion-pairing system using tetrabutyl ammonium chloride allows also the simultaneous determination of acetaminophen and its three major metabolites with those of styrene in rat urine. Simplicity, reproducibility and a short analysis time provide a useful tool for the toxicokinetic studies of these two hepatorenotoxic xenobiotics after their co-administration. An aliquot of the diluted urine is directly injected into the liquid chromatograph. The limits of sensitivity and detection of the metabolites of styrene are better than those reported before. Preliminary works indicate that the method would also be applicable for analysis of these metabolites in human urine and would therefore be useful in monitoring styrene exposure to workers especially when they take acetaminophen.

Acetaminophen↗
PubMed1986

Characterization of SV40 chromatin by mass determination on STEM.

Direct mass determination of purified SV40 minichromosomes was obtained by scanning transmission electron microscopy. Twenty to thirty percent of the minichromosomes were found with an Mr of 6.9 +/- 0.4 X 10(6). The rest of the molecules formed a spread Mr distribution ranging from 7.3 X 10(6) to 9.5 X 10(6) due possibly to different contents of the virus-coded proteins, mainly VP1. The apparent mass histogram of individual SV40 nucleosomes presents three maxima at Mr 2.1 X 10(5), 2.6 X 10(5) and 3.1 X 10(5) that could correspond to partially unravelled nucleosomes, complete nucleosomes and complete nucleosomes with the addition of VP1. Beaded structures with a higher mass were also measured; some were found at either side of the open nucleosome-free region.

Chromatin↗
PubMed1986

Influence of resident Salmonella on contamination of broiler flocks.

An epidemiological survey was made of 5329 samples from 10 poultry operations to determine the relationship between total poultry farm environment and incidences of Salmonella contamination of broiler flocks. Samples were analyzed from walls, drinkers, feeders, litter, insects, water, chicks, broilers, and feed to determine the effect of common sanitary practices on Salmonella contamination of flocks. Results indicated that although similar hygienic practices had been taken on the 10 poultry farms examined, great variation exists in Salmonella contamination among the farms. Among the sources studied, the most important source of contamination was determined to be the resident Salmonella of the flock i.e., the strain isolated on chicks' first day in the poultry house. This source was more important than Salmonella isolated during the rearing period. However, the precise conditions of Salmonella contamination in poultry flocks remain to be elucidated.

Animals↗
PubMed1986

Evaluation of an enzyme immunoassay for estrogen receptors in human breast cancers.

An estrogen receptor enzyme immunoassay kit (ER-EIA) has been evaluated in 70 human breast carcinomas against a routine cytoplasmic [3H]estradiol binding assay (ERU). A linear correlation between the ER-EIA and the ERU was observed for binding values up to 400 fmol/mg of cytosol protein. Above this value, the ERU underestimates the concentration of receptor. The ERU gave a lower number of estrogen receptor-positive tumors (50 of 70) than did the ER-EIA assay (59 of 70). In the ERU-negative ER-EIA-positive tumors, receptor values as determined by the ER-EIA assay all fell below 50 fmol/mg of protein (mean, 19.9 +/- 4.2 fmol/mg of protein). Application of an exchange procedure which estimates the total steroid binding capacity of the cytosol gave positive results in 7 of 9 ERU-negative ER-EIA-positive tumors (mean, 16.9 +/- 2.95 fmol/mg of protein). Subdivision of the binding data according to the menopausal status of the patient indicates low receptor values in premenopausal women by each assay. A correlation between the ER-EIA assay and the histological grade of tumors was observed; Grade I well-differentiated tumors were all positive, while Grade II and III tumors were 86% and 75% positive, respectively. No correlation between the ER-EIA assay and tumor lymph node stage or tumor size was observed.

Adult↗
PubMed1986

Effects of route of administration on the dose-dependent metabolism of acetaminophen in rats: relationship with its toxicity.

The urinary metabolic excretion profile of acetaminophen (A) was reexamined in adult male Sprague-Dawley rats after administration of a single intraperitoneal (i.p.) or per oral (p.o.) dose of 100 or 750 mg/kg to 4 groups of animals, followed by collecting urines at 8, 24, 48 and 72 hr. The higher dose was administered in the form of a micronized suspension. The amounts of glucuronide, sulfate and mercapturate of A and unchanged A excreted in the urines were measured as a function of time. The pattern of urinary metabolic excretion of A was found to be dependent not only on the dose, but also on its route of administration as well as on the time of urine collection. When A was administered orally, the drug appears to be subjected to a gut and/or gut-wall first-pass elimination. The mean total urinary recovery of the drug was 70% after 72 hr following the administration of the higher dose of A. The hepatorenal toxicity was assessed by measuring the levels of serum glutamic-pyruvic transaminase activity and of urinary creatinine. The higher dose of A showed the potential to produce hepatic and renal toxicity when given i.p., but not when given orally. These toxic effects seem to be related with a high percentage of urinary A mercapturate and unchanged A when A was given i.p. as compared to those when it was given orally.

Acetaminophen↗
PubMed1985

Relationship between serotypes of Salmonellae from hatcheries and rearing farms and those from processed poultry carcases.

The influence of the hatchery and the poultry farm on the contamination of poultry carcases by Salmonella species has been studied by examining samples from different stages of production. The incidence of Salmonella serotypes in the hatchery varied considerably in different broiler flocks and decreased from the beginning to the end of the rearing period. Serotypes originating in the hatchery were less important in the final product than those present in the house, or those introduced into the house by vectors during rearing.

Abattoirs↗
PubMed1984

Cimetidine interaction with dipotassium clorazepate disposition in the anesthetized dog.

Cimetidine (CIM) was used as an interacting agent on the disposition in dogs of dipotassium clorazepate ( CZP ) and its main metabolite nordiazepam (ND) in order to study some of the factors contributing to pharmacokinetic interspecies variation of benzodiazepines in dogs and man. A 0.5 mg/kg of body weight intravenous (i.v.) bolus dose of CZP was administered to 12 anesthetized mongrel dogs, 6 of them receiving also, 30 min before, a 1 mg/kg i.v. bolus dose of CIM followed by a constant i.v. infusion (1 mg/kg/hr) of CIM. Plasma ND and CZP concentrations were measured as a function of time with an high-performance liquid chromatography method. Plasma levels of CZP declined mono- and biexponentially in 1 and 5 dogs, respectively, for each group of animals. No statistically significant difference was found between CZP pharmacokinetic parameters when the 2 groups of dogs were compared. However, a 37% decrease in ND beta half-life, t1/2 beta, when CZP was associated with CIM, was found to be statistically significant. The i.v. administration of pure ND in two dogs, has shown that ND declines biexponentially with a t1/2 beta similar to the one estimated after CZP dosing in control animals. The hepatic metabolism of ND was found to be flow-independent and restrictive. The data, along with previously reported CIM interactions, suggest that several factors, which would be species-dependent, must be responsible of CIM effect on other drugs.

Anesthesia↗
PubMed1984

[Myasthenia and Basedow's hyperthyroidism].

The authors report an exceptional case of myasthenia gravis associated with Graves' disease. Myasthenia gravis appeared at age 8 years. Hyperthyroidism was diagnosed at age 12 1/2 and quickly worsened, with signs of cardiothyrotoxicosis. In addition to the diagnostic difficulties, the immunologic origin seems to be implicated in these diseases. Thymectomy associated with subtotal thyroidectomy was performed, with good results during an 18 months follow-up.

Child↗
PubMed1983

High-performance liquid chromatography determination of dipotassium clorazepate and its major metabolite nordiazepam in plasma.

A rapid and sensitive high-performance liquid chromatographic method is described for the quantitative analysis of dipotassium clorazepate (CZP) and its major metabolite nordiazepam (ND) in fresh human and dog plasma. The method consists of two separate selective ND extractions from a plasma sample without and with conversion of all the CZP to ND. For quantitation, diazepam (DZP) is used as the internal standard. The chromatographic phase utilized in a reversed-phase Hibar EC-RT analytical column prepacked with LiChrosolv RP-18 with a solvent system consisting of acetonitrile-0.05 M sodium acetate buffer, pH 5.0 (45:55). The UV absorbance is monitored at 225 nm using a variable-wavelength detector. The mean assay coefficient of variation over a concentration range of 20-400 ng per ml of plasma is less than 3% for the within-day precision. Recoveries of ND, DZP and CZP (as ND) are essentially quantitative at all levels investigated. The calibration curves of ND are rectilinear (r2 = 0.99) from the lower limit of sensitivity (2 ng/ml) to at least 2000 ng/ml in plasma. Applicability of the method to CZP and ND disposition studies in the anaesthetized mongrel dog is illustrated. When the two separate selective nordiazepam extractions from plasma cannot be performed immediately after blood sampling, an extrapolation kinetic method is suggested for the estimation of CZP concentration. In all previous in vivo studies, CZP has been determined only with gas-liquid chromatographic methods.

Animals↗
PubMed1975

[Primary malignant tumor of the liver in children].

Primary malignant tumours of the liver in children are rare. They occur in more than 50% of cases before the age of 2 years. The clinical signs are very often limited to a large mass in the right hypochrondrium. A search for alphafoetoprotein and arteriography are the most useful investigations for diagnosis. The pathology leads one to distinguish hepatoblastomas and hepatocarcinomas. The prognosis in these tumours remains poor for, in spite of progress in liver surgery, a cure is rarely possible. It is important for doctors to recognize the existence of this tumour pathology in order to give a chance for surgery to succeed in these young children. To illustrate this, 5 cases from Besançon are reported here.

Adolescent↗