Search PubMed⌕ Search

Biomedical subjects

P Georges

Publications and source records attributed to P Georges.

At least 37 records · Page 2Linked to original sources

[Thyroid hormone determination at the Public Assistance Hospital of Paris: ordering, costs and opinions of physicians qualified in endocrinology].

OBJECTIVES: To determine the distribution of orders for hormonal tests assessing thyroid function in a hospital setting. To collect the opinion of physicians specialized in endocrinology concerning free triodothyronine (FT3) assessment. METHODS: Using a cross-sectional survey numbers of free thyroxine (FT4), total T4 (TT4), FT3, total T3 (TT3), and TSH tests were collected from the heads of laboratory assessing thyroid function in June 95 at the Assistance Publique-Hôpitaux de Paris (AP-HP). Cost for these tests was estimated. The physicians of the AP-HP specialized in endocrinology were asked through a questionnaire for circumstances justifying FT3 test ordering. RESULTS: Twenty-eight laboratories (93%) responded: 28455 measurements (TSH: 43%, FT4: 33%, TT4: 2%, FT3: 20%, TT3: 2%) were performed and were valued at 3.4 million French Francs. Proportions of T4 (36%) and T3 (20%) tests were lower in hospitals with an inpatient department of endocrinology than in hospitals with an outpatient clinic with specialists in endocrinology (T4: 36%; T3: 27%) or with no endocrinology unit (T4: 33%, T3: 27%); proportion of TSH tests was higher in hospitals with an inpatient endocrinology unit (respectively 44%, 40%, 32%). Forty-two endocrinologists (76%) from 21 departments answered. Follow-up of treatment with amiodarone and euthyroid sick syndrome were considered the only conditions justifying FT3 test ordering. CONCLUSION: Though the opinion of physicians specialized in endocrinology was not uniform regarding recommendations for TT3 or FT3 tests as a first-line measurement, the cost of these tests has been estimated at 650 thousand Francs for a month at the AP-HP.

Costs and Cost Analysis↗

Urinary growth hormone excretion: results of a multicenter study in France.

Urinary growth hormone excretion (uGH), expressed as the average of three consecutive nocturnal measurements, was studied in 324 prepubertal and pubertal children without (n = 188) or with (n = 136) growth disorders. In prepubertal control children (n = 127), the mean uGH was 11.9 +/- 4.9 ng/l without any correlation with sex or age. During puberty, a significant increase of uGH was observed in both sexes (boys: prepubertal 12.3 +/- 4.84 vs. pubertal 16.2 +/- 4.7 ng/l; girls: prepubertal 11.6 +/- 4.99 vs. pubertal 18.3 +/- 8.5 ng/l). In children with growth disorders, the results observed in various categories show a highly significant decrease in organic hypopituitary patients (p < 10(-6)) and obese subjects (p < 10(-6)) when compared to normal prepubertal children. In contrast, a significant increase was observed in 5 Laron-type dwarfisms (p < 10(-6)). However, in 24 children with partial growth hormone deficiency assessed by blood measurements (two pharmacological tests between 5 and 10 ng/ml), the results were not significantly different from the controls (13.6 +/- 6.4 ng/l). In a group of 66 children with short stature and normal blood response to pharmacological tests, uGH concentrations were significantly higher than those of the control group (17.3 +/- 8.71 ng/l, p < 10(-6)). The data suggest that uGH measurements lead to findings comparable to blood measurements, avoiding the disturbance of pharmacological tests, in well-delimited categories of patients. In contrast, uGH measurements are not the best way to detect partial GH-deficient children, but may be used to screen partial peripheral GH resistance in children with nonendocrine short stature.

Adolescent↗

Differences in pain medication use in stroke patients with aphasia and without aphasia.

BACKGROUND AND PURPOSE: While individuals with stroke are known to experience pain for a variety of reasons including premorbid conditions and stroke-specific sequelae, there are some groups of individuals with stroke, who because of aphasia, are unable to express their pain. This study investigated whether there exists an association between severity of aphasia and overall pain medication use as indicated (1) by the proportion of individuals medicated according to aphasia severity and (2) by the dosage of pain medication used according to aphasia severity. METHODS: The study involved a retrospective chart review of 207 charts of patients with stroke admitted to the Jewish Rehabilitation Hospital (JRH), Laval, Canada. Patients were classified into three groups according to level of expressive aphasia: those without aphasia, those with mild-to-moderate aphasia, and those severe aphasia. Information on medications used primarily for pain management was elicited for the first 21 days and the last 5 days of hospitalization. Any substitution, increase, elimination, or addition of pain medication during hospitalization was also monitored. RESULTS AND CONCLUSIONS: While the findings indicate that pain medication prescriptions were similar for all patients, a significantly smaller number of individuals with aphasia received pro re nata (prn) "as required" pain medication when compared with those without aphasia, for the first 21 days and for the last 5 days of hospitalization at the JRH. Similarly, when daily dose was monitored for the same time periods, individuals with aphasia were found to have received less medication for pain than those without aphasia.

Aged↗

Amoebicidal efficiencies of various diamidines against two strains of Acanthamoeba polyphaga.

The first medical cure of Acanthamoeba keratitis was obtained by use of propamidine isethionate. Since then, it has been the basic drug recommended for use in treatment. Because some Acanthamoeba strains have been reported to be resistant to propamidine and propamidine was found to be only weakly cysticidal, superior homologs such as butamidine, pentamidine, hexamidine, heptamidine, octamidine, and nonamidine were tested for their amoebicidal effects on two Acanthamoeba strains isolated from patients with keratitis. Trophozoicidal and cysticidal efficiencies were found to be increased from propamidine to nonamidine; i.e., when the alkyl chain connecting the two benzene rings in their molecular structures was elongated, in comparison with propamidine, hexamidine and octamidine were the most amoebicidal molecules. As a result of these data, a kinetic study carried out on propamidine, hexamidine, and octamidine demonstrated that the amoebicidal effects resulted from two events: the diffusion of molecules through the plasma membrane or the double wall of trophozoites or cysts, respectively, and the lethal effects of molecules on amoebic protoplasm. The diffusion kinetics were increased when the alkyl chain was elongated, i.e., with an increase in the lipophilic properties of molecules. In contrast, the lethal effect kinetics were found to be unchanged by this elongation, indicating that they originated from the cationic surface-active properties induced by the protonated amidine groups attached to each benzene ring, which themselves remained unchanged from one molecule to the other. These results strongly advocate the immediate replacement of propamidine by hexamidine in the medical treatment of Acanthamoeba keratitis; in France, 0.1% hexamidine eyedrops are available (Desomedine). The results also advocate clinical investigations on the efficiency and toxicity of octamidine, which appears to be the most amoebicidal diamidine in vitro.

Acanthamoeba↗

[IgE-dependent hypersensitivity to the cockroach in children. Mesologic approach].

CAP-RAST* i6 was systematically performed in sera of 400 children and adolescents admitted in an allergy unit. The frequency of this sensitisation was 0.238 among allergic subjects. In the whole population discriminant factors were 1) the age of the patient, 2) clinical asthma. A case-control study revealed: 1.) more marked atopic criteria (house dust mite and/or timothy grass pollen associated sensitizations; increased IgE level); 2.) sociologic factors: popular housing and immigrant families. It was already stated that these immigrant populations had enhanced predisposition to develop asthma. This propensity, reinforced by unfavourable environment, indicates immigrant families as high risk population for respiratory allergy.

Adolescent↗

[Biological and parasitic variations in horses infested and reinfested by Trichinella spiralis].

Seven mares were infected with 20,000 Trichinella spiralis larvae; 2 of them were reinfected 22 wk later with the same amount of larvae. The course of infection in horses was assessed by serology (ELISA), biochemistry (aldolase activity), parasitology and histopathology. In each animal, infection was followed by a significant rise in specific antibody titers culminating at 5-10 wk post-infection (pi) and decreasing thereafter. Reinfection was followed by a slight rise in antibody levels. Aldolase activity increased during the first infection, but was not modified by reinfection. The parasite burden was maximum 20 wk pi (24-145 larvae/g according to localisation) and was very low at 52 wk pi (0.4-5 larvae/g). Compared to mares infected only once, the number of parasites in the reinfected animals was similar 28 wk pi but much lower 40 wk pi. Moreover, 6 wk post-reinfection, the larvae were surrounded by a large inflammatory granuloma which could have been caused by larvae from the reinfection batch. These experiments confirm the susceptibility of horses to Trichinella spiralis and the rapid disappearance of specific antibodies which prevents usual serological methods from being used in the diagnosis of infected animals. Reinfection could help the horse to eliminate the larvae more rapidly.

Animals↗

[Value (and limitations) of the RAST fx5 in pediatric allergological practice].

RAST f x 5 (CAP-system, Pharmacia), an in vitro assay testing a mixture of 6 food antigens, was systematically applied to 400 children and adolescents with respiratory pathologies possibly of allergic origin. The clinical aspects of the 293 test-negative patients were compared with those of the 107 positive cases. Furthermore, 84 positive sera were also evaluated against each of the 6 antigens regrouped in the f x 5. In this population with allergic respiratory diseases, the most frequently positive tests reacted with antigens of plant origins: wheat, peanut and soybean. From an economic point of view, first-line use of f x 5 markedly reduced the cost of a systematic study of food allergens, whose clinical justification remains to be demonstrated.

Adolescent↗

[Serum creatinine assay: results of a multicentric study with 16 analytical systems].

During a multicenter evaluation, 16 methods for creatinine measurement have been tested according to the guidelines of the Société française de biologie clinique (SFBC) protocol. Kinetic Jaffé methods, widely used in France, performed on different analytical systems (Astra Beckman, IL 508, RA 1000 Technicon, Hitachi 704, 705, 717 Boehringer, Fara Roche, Progress Kone, Kem-O-Mat Coulter, Perspective France Monitor) have been compared to a continuous flow method with aqueous standards, to enzymatic methods using creatinine amidohydrolase with a colorimetric measurement (Boehringer and Ektachem Kodak) and to an HPLC method. Reproducibility, estimated with four different control sera, proved to be unsatisfactory in some cases as compared to current criteria for imprecision (less than +/- 10 mumol/l for intralaboratory and less than +/- 20 mumol/l for interlaboratory imprecision). The same selected patients sera covering the whole range of physiopathological concentrations have been analyzed with each method, and compared with the continuous flow results. Differences are more dependent on the sample than on the calibrators. The influences of haemolysis, bilirubin, acetoacetate, albumin, lipids, glucose, and some cephalosporins have been evaluated with spiked human sera. Haemolysed, turbid and jaundiced patient samples have been analyzed as well. The results vary according to the analytical procedure. This study took place in the implementation of a selected method for routine purpose with special regards to interferences and an acceptable imprecision. The method must satisfy the physicians' demands in the renal function exploration, especially in kidney-transplant patients.

Biological Assay↗

Reversibility of spermine-induced intestinal maturation in the rat.

In the present investigation, the reversibility of spermine-induced precocious intestinal maturation was studied. Neonatal rats received either saline or spermine (4 mumol, twice daily) solution orally on the 11th and 12th postnatal day. They were killed on the 13th, 14th, 15th, 16th, and 17th postnatal days. After the small bowel was removed, it was either divided into three equal parts or prepared for electrophoretic analysis. Histological examination, protein content measurement, and disaccharidase activity estimation were performed on each part of the intestine. Spermine administration was shown to induce structural and mucosal enzyme changes characteristic of postnatal maturation. This phenomenon, which was generally clearly observed in 13- and 14-day-old rats, then became less apparent in 15- and 16-day-old animals. Differences were noted according to the segment of intestine or the biochemical parameter analyzed. When rats were 17 days old, no significant differences generally existed between control and spermine-treated rats. If the 140- to 150-kDa proteins, isolated by electrophoresis, are assumed to represent the subunits of the sucrase-isomaltase complex, the results obtained indicate that spermine induces a modification of the concentration of this complex. When compared to values obtained in adult rats, the concentration of the complex was approximately three times higher in spermine-treated 13-day-old rats, while no differences were found in spermine-treated 14-day-old rats. Further, similar concentrations were found in control and spermine-treated rats with an age of 17 days. These results suggest that spermine-induced precocious intestinal maturation is reversible when spermine treatment is stopped.

Animals↗

Increase of IGF I binding to erythrocyte receptors during the TRH-test: correlation between IGF I binding and thyroid hormone values.

The effects of TRH on insulin-like growth factor I receptors were investigated on erythrocytes from 7 GH-deficient children having plasma GH levels less than 10 ng/ml during two provocation tests. Intravenous injection of synthetic TRH (0.2 mg/m2) was followed by a marked increase of IGF I binding on erythrocytes, from 3.9% +/- 0.3% to 5.9% +/- 0.3% (P less than 0.005) after 1 hour and 7.3% +/- 0.4% (P less than 0.005) after 2 hours. The IGF I binding variations were due to an increase in both the receptor affinity and the number of sites. The levels of plasma GH, IGF I, T3, T4, free T4, TSH and prolactin having been determined during the TRH test at 0, 1 hour, and 2 hours after the injection, the increase in the IGF I binding to erythrocytes at the same time correlated with the rise of thyroid hormones: triiodothyronine T3 (P less than 0.001) and thyroxine T4 (P less than 0.005) and not with the level of the other hormones. These findings suggest that thyroid hormones play a role in the regulation of insulin-like growth factor I receptors.

Child↗

Parasitic hazard with sewage sludge applied to land.

A modification of the FAUST technique allowed a highly regular recovery of Taenia saginata eggs from sewage sludge, as well as their quantification. Despite the low viability (8%) noted, the viable T. saginata egg level remains high (20.10(6)/ha) and offers a serious risk for cattle even after a 3-week "no-grazing" period.

Animals↗

Experimental trichinellosis in horses: biological and parasitological evaluation.

Three groups of three horses each were, respectively, infected with 5000, 20,000 and 50,000 larvae of Trichinella spiralis. The strain used was isolated from a human biopsy during horsemeat-related outbreaks of trichinellosis in France. Transient muscular disorders were only observed in two of the horses infected with 50,000 larvae but none of the horses had fever. A significant increase in blood eosinophils was noticed in 5 horses. Serum LDH, aldolase and CPK peaked at the fifth week post-infection. Specific IgG assayed by indirect immunofluorescence and ELISA, appeared 2-5 weeks post-infection and disappeared between 16 and 40 weeks. The distribution of T. spiralis larvae was maximal in the tongue, masseters and diaphragm, but a large decrease in the number of larvae recovered from the muscles was noticed among the horses slaughtered at the beginning and end of the experiment. In muscular histological sections, larvae were observed in an intramyofibrillar position and were surrounded by a mild to severe inflammatory reaction.

Animals↗

Predicting falls among patients in a rehabilitation hospital.

A retrospective case-control study within a cohort was carried out to identify factors associated with falling by patients in a rehabilitation hospital. The cohort comprised all patients admitted during a 2-year period from 1984 to 1986. Cases were those who fell one or more times during their hospitalization. For each case, one control matched on sex and date of admission, was chosen. Material from the first year of the cohort (201 cases and 201 controls) was used to define a model to estimate the risk of falling. Of the more than 100 variables considered in the conditional logistic regression models, stroke, incontinence, anticonvulsant medications, and topical eye preparations were significantly associated with the risk of falling. Analyses carried out on the second year of the cohort (155 cases and 155 controls) confirmed the predictive ability of these four variables. By combining the material from both subcohorts we were able to determine that a program to reduce falls directed towards stroke patients and incontinent patients alone could, theoretically, prevent 44% of first falls.

Accidental Falls↗

Tyrosine content, influx and accumulation rate, and catecholamine biosynthesis measured in vivo, in the central nervous system and in peripheral organs of the young rat. Influence of neonatal hypo- and hyperthyroidism.

The influence of neonatal hypo- and hyperthyroidism on different aspects of tyrosine metabolism in the hypothalamus, striatum, brainstem, adrenal glands, heart and brown adipose tissue (BAT) were studied in 14-day old rats. The synthesis rate of catecholamines (CA) was also determined in vivo after the injection of labelled tyrosine. Hypothyroidism increases tyrosinaemia and endogenous tyrosine concentration in the hypothalamus and BAT. Hyperthyroidism decreases tyrosinaemia and endogenous tyrosine levels in the striatum, adrenals and heart. The accumulation rate of tyrosine determined 30 min after an intravenous injection of the labelled amino acid has been determined in the organs, together with the influx of the amino acid, determined within 20s. Hypothyroidism increases tyrosine accumulation rate in all the organs studied, and tyrosine clearance is decreased in the striatum and brainstem; together with an increased tyrosinaemia, this leads to a normal influx. The influx of tyrosine is increased in the hypothalamus. Hyperthyroidism decreases tyrosine accumulation rate in all the organs except the adrenals. These results indicate that the thyroid status of the young rat can influence tyrosine uptake mechanisms, without modifying an organ's tyrosine content. The fact that hypothyroidism increases tyrosine influx in the hypothalamus without modifying it in the brainstem and striatum reflects an heterogeneous reactivity to the lack of thyroid hormones in different brain structures. Neonatal hypothyroidism decreases the CA synthesis rate in the striatum, the heart and the interscapular brown adipose tissue, while synthesis was enhanced in the brainstem and the adrenals. It is likely that these variations in CA synthesis are due to thyroid hormone modulation of tyrosine hydroxylase activity, the enzyme which catalyses the rate limiting step in CA biosynthesis.

Adipose Tissue, Brown↗

[Possibility of the survival of free-living amoebae which cause keratitis in decontamination solutions used for the maintenance of contact lenses].

Because Acanthamoeba keratitis associated with contact lenses were described, several solutions used in stationary eye wash stations were contaminated by free-living amoebae. 0.9% sodium chloride rinsing solutions allowed cyst and trophozoite growth and only one solution for decontamination using hydrogen peroxide led to rapid elimination of cysts and trophozoites. Antiseptic solutions containing ammonium derivatives or chlorhexidine killed only trophozoites. Because of the constant contamination of tap water with Acanthamoeba cysts resistant to chlorine, the prevention of amoebic keratitis in wearers of contact lenses needs: use of sterile solutions for decontamination or rinsing, choice, if possible, of oxidizing solutions, suppression of tap water for rinsing.

Acanthamoeba↗

Effect of HECNU in malignant supratentorial gliomas--a phase II study.

Forty adults with recurring brain gliomas were treated with HECNU 130 mg/m2, given i.v. every 5 to 6 weeks (mean 5.4) and corticosteroids. According to the response to treatment, patients were divided in 3 groups: 1. Group 1 included 8 pts (20%) with objective remission, defined as a clear-cut clinical improvement persisting at least 4 weeks after the complete discontinuation of corticosteroids. 2. Group 2 included 14 patients (35%) who improved or remained stable yet stayed corticosteroid-dependent. 3. The 18 patients (45%) of group 3 failed to respond. There was a fair correlation between clinical and radiological response. Thus sequential CT-scans showed a 50 to 100% tumour reduction in all patients of group 1, and in 5 of group 2. CT-scans remained unchanged in 8 patients of group 2 and in one of group 3, and showed tumour progression in 10 patients of group 3. Drug toxicity appeared mild, reversible and was not cumulative. The better tolerance of HECNU could represent a real advantage of this drug over the commonly used nitrosourea derivatives such as BCNU and CCNU.

Adult↗

In vitro chemosensitivity of brain tumors to cisplatin and its analogues, iproplatin and carboplatin.

The human tumor stem-cell assay was used to investigate the in vitro chemosensitivity of 27 evaluable samples to cisplatin and its analogues, iproplatin and carboplatin, as well as to BCNU, teniposide, vindesine, and dibromodulcitol. All agents exhibited some antitumor activity with the exception of dibromodulcitol (zero response out of 19 evaluable samples). Vindesine, BCNU, and carboplatin were the three most active compounds, with response rates of 29%, 23%, and 22%, respectively. There was a lack of complete cross-resistance between carboplatin and cisplatin as well as between carboplatin and BCNU. Our data suggest that clinical studies with carboplatin and combinations of vindesine plus cisplatin and its analogues may be worthwhile.

Brain Neoplasms↗