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1.
J Environ Radioact ; 121: 43-54, 2013 Jul.
Article in English | MEDLINE | ID: mdl-22608977

ABSTRACT

Apart from radiocaesium and radiostrontium, there have been few studies on the foliar transfer of radionuclides in plants. Consequently, specific translocation factor (ftr) values for (129)I, (79)Se and (36)Cl are still missing from the IAEA reference databases. The translocation of short - lived isotopes, (125)I and (75)Se, and of (36)Cl to wheat grain were measured under field conditions following acute and chronic wet foliar contamination at various plant growth stages in the absence of leaching caused by rain. The translocation factors ranged from 0.02% to 1.1% for (125)I (a value similar to Sr), from 0.1% to 16.5% for (75)Se, and from 1% to 14.9% for (36)Cl. Both (36)Cl and (75)Se were as mobile as Cs. The phenomenological analysis showed that each element displayed a specific behavior. Iodide showed the lowest apparent mobility because of its preferential fixation in or on the leaves and a significant amount probably volatilized. Selenite internal transfer was significant and possibly utilized the sulphur metabolic pathway. However bio - methylation of selenite may have led to increased volatilization. Chloride was very mobile and quickly diffused throughout the plant. In addition, the analysis underlined the importance of plant growth responses to annual variations in weather conditions that can affect open field experiments because plant growth stage played a major role in ftr values dispersion. The chronic contamination results suggested that a series of acute contamination events had an additive effect on translocated elements. The highest translocation value obtained for an acute contamination event was shown to be a good conservative assessment of chronic contamination if data on chronic contamination translocation are lacking. The absence of rain leaching during the experiment meant that this investigation avoided potential radionuclide transfer by the roots, which also meant that radionuclide retention on or in the leaves was maximized. This study was therefore able to obtain accurate translocation factors, which are probably among the highest that could be recorded.


Subject(s)
Chlorine/pharmacokinetics , Iodides/pharmacokinetics , Plant Leaves/radiation effects , Radioisotopes/pharmacokinetics , Seeds/radiation effects , Selenious Acid/pharmacokinetics , Triticum/radiation effects , Biological Transport/radiation effects , Food Contamination, Radioactive , Iodine Radioisotopes/pharmacokinetics , Plant Leaves/metabolism , Radioactive Pollutants/pharmacokinetics , Rain , Seeds/metabolism , Selenium Radioisotopes/pharmacokinetics , Triticum/growth & development , Triticum/metabolism
2.
Rev Stomatol Chir Maxillofac ; 111(5-6): 296-8, 2010.
Article in French | MEDLINE | ID: mdl-21111435

ABSTRACT

The impact of anosmia or ageusia may be considerable for some occupations. Expert assessment shows how difficult it is to prove the diagnosis. A specialist is usually needed to demonstrate the asserted disorder. Damage compensation is based on the patient's occupation and coverage.


Subject(s)
Craniocerebral Trauma/complications , Forensic Medicine , Olfaction Disorders/etiology , Taste Disorders/etiology , Diagnosis, Differential , Disability Evaluation , Electrodiagnosis , France , Humans , Olfaction Disorders/diagnosis , Olfactory Nerve/physiopathology , Taste Disorders/diagnosis , Tongue/physiopathology , Trigeminal Nerve/physiopathology
3.
J Environ Radioact ; 100(10): 847-53, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19596497

ABSTRACT

The decrease of foliar activity in vegetation after its initial contamination by foliar deposition is termed "field loss" (Chamberlain, 1970). This work investigated further laboratory data concerning field loss of (134)Cs, (137)Cs, (85)Sr, (133)Ba and (123m)Te deposited on grassland (Madoz-Escande et al., 2005). Treatments consisted in rainfall scenarios cumulating 14 mm per week, combining two levels of intensity (8 or 30 mm/h) and two levels of frequency/precocity (late once or early twice-a-week). The time course of field loss was monitored in the edible tissues which were sampled by mowing between the rainfalls. Data were analyzed with an offset exponential loss model which is applicable to chronic contamination and is consistent with approaches adopted in radiological assessment models. Its parameters were estimated by the maximum-likelihood method, and their accuracy was determined by nonparametric bootstrap. Radionuclide and rainfall conditions significantly affected the estimated rate (lambda(1)) and extent (A(1)) of field loss. Field loss rate (lambda(1)) and nonentrainable fraction (1-A(1)) varied by a factor 1.5-3. Cesium was very mobile but persistent. On the contrary Tellerium was found less labile, but eventually was almost completely eliminated. Strontium and Barium had intermediate behaviors. Field loss was more efficient for moderate late once-a-week rainfalls (8mm/h). Higher rainfall intensity reduced more the radionuclides losses than higher rainfall frequency/precocity. This paper reports statistically relevant effects that should be considered for more realistic assessments.


Subject(s)
Plant Leaves/radiation effects , Poaceae/radiation effects , Radioactive Pollutants/analysis , Radioisotopes/analysis , Rain , Barium Radioisotopes/analysis , Cesium Radioisotopes/analysis , Kinetics , Models, Chemical , Radioactive Fallout , Strontium Radioisotopes/analysis , Tellurium/analysis
4.
J Environ Radioact ; 100(9): 683-9, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19019504

ABSTRACT

A review of the published literature about foliar transfer radionuclides to cereal grains was carried out with a special interest for translocation factors. Translocation describes the distribution of radionuclides within the plant after foliar deposition and radionuclide absorption onto the surface of leaves. It mainly depends on elements and the plant growth stage. The collected data were derived from both in-field and greenhouse experiments. They were analysed in order to select those coming from a contamination simulating a sprinkling irrigation or a rain. The data set contains 307 values. For each radionuclide the translocation factor values were sorted according to 5 characteristic stages of the cereal vegetative cycle: leaf development-tillering, stem elongation, earing-flowering, grain growth and ripening. Wheat, barley and rye have been treated together, independently of rice. For mobile elements such as cesium, the translocation factor is maximum when the contamination occurred at the earing-flowering stage. For less mobile elements such as strontium this maximum occurred for a foliar contamination at the grain growth stage. This review enabled us to propose the most probable value as well as the range of variation of translocation factors for some radionuclides according to the cereal vegetative cycle. Moreover, from these results, a radionuclide classification is proposed according to three mobility groups.


Subject(s)
Edible Grain/metabolism , Plant Leaves/metabolism , Radioisotopes/metabolism , Cesium Radioisotopes/metabolism , Hordeum/metabolism , Secale/metabolism , Strontium Radioisotopes/metabolism , Triticum/metabolism
5.
J Laryngol Otol ; 123(5): 550-4, 2009 May.
Article in English | MEDLINE | ID: mdl-18796181

ABSTRACT

OBJECTIVE: To analyse correlations between quality of life measures, aspiration and extent of surgical resection in patients who have undergone free-flap tongue reconstruction. PATIENTS AND METHODS: Nine consecutive patients (seven men and two women; average age 51 years) who had been diagnosed with T4a carcinoma of the mobile tongue and/or tongue base and treated by glossectomy, free-flap reconstruction, and either radiation therapy or chemoradiation responded to the European Organization for Research and Treatment of Cancer Head and Neck-35 questionnaire, the performance status scale questionnaire and the hospital anxiety-depression scale questionnaire, an average of 43 months after treatment (range 18-83 months). Aspiration was evaluated by fibre-optic laryngoscopy. Correlations between quality of life domain scores, extent of surgery and the presence of aspiration were evaluated using non-parametric statistical analysis. RESULTS: Scores for the swallowing and aspiration domains of the European Organization for Research and Treatment of Cancer Head and Neck-35 questionnaire were significantly correlated with the extent of tongue base resection (Spearman's correlation, p = 0.037 and 0.042, respectively). Despite a strong correlation between the European Organization for Research and Treatment of Cancer Head and Neck-35 questionnaire results and the performance status scale global scores (correlation coefficient = 0.89, p = 0.048), the performance status scale domain scores were not correlated with the extent of tongue resection. Clinically apparent aspiration was not correlated with the extent of tongue resection, nor were the anxiety or depression scores. However, clinically apparent aspiration was significantly related to the swallowing and aspiration domain scores of the European Organization for Research and Treatment of Cancer Head and Neck-35 questionnaire (p = 0.017 in both cases). CONCLUSIONS: Our results imply that the volume of tongue base resection is a major factor in swallowing- and aspiration-related quality of life following tongue resection and free-flap reconstruction. Free-flap reconstruction does not seem to palliate the effect of the loss of functional tongue base volume, as regards swallowing-related quality of life.


Subject(s)
Carcinoma/surgery , Plastic Surgery Procedures/methods , Tongue Neoplasms/surgery , Tongue/surgery , Adult , Aged , Female , Humans , Male , Middle Aged , Quality of Life/psychology , Respiratory Aspiration/surgery , Surgical Flaps , Surveys and Questionnaires , Treatment Outcome
6.
J Environ Radioact ; 89(1): 30-47, 2006.
Article in English | MEDLINE | ID: mdl-16713039

ABSTRACT

(137)Cs, (85)Sr, (133)Ba and (123m)Te contaminations of terrestrial gastropods, Helix aspersa maxima, by direct deposition, labelled food ingestion or combined (trophic and direct pathways) exposure were carried out under laboratory conditions. The aim of this study was to compare the three contamination pathways: direct, trophic and combined, in terms of individual mortality, radionuclide uptake, depuration and distribution in the tissues. An initial group of 30 snails (2 years old) was exposed to radioactive aerosols during a 20-h period. These aerosols were assumed to be representative of those that would be released during a nuclear accident occurring in a PWR. A second group of 50 snails (same age) was submitted to an ingestion of commercial food contaminated by the same aerosols, twice a week for 21 days (flour at a feeding rate of about 0.2g). A third group of 40 snails was submitted to a combined exposure: exposure to radioactive aerosols (20h), followed by ingestion of flour contaminated by the same aerosols, twice a week for 21 days. No significant difference between the three groups and a reference group of 10 snails was observed, neither in growth nor in mortality. Concerning the direct pathway, at the end of direct deposition (about 1 day after the beginning), cesium was the most bioavailable element, distributed rather homogeneously throughout the whole body (13% of the total Cs in all organs excepting the digestive system and 28% in the muscle). Strontium was measured in the shell (about 70%). Barium was found in the muscle (20%) and in the shell (65%). Tellurium was mainly present in the shell (70%) and in the digestive system (20%). After 21 days of depuration, the faeces eliminated 42% of the Te. As for contamination by ingestion, Te mainly accumulated in the digestive system (72% of Te present in the total body), Ba accumulated in the muscle (75%) and Sr in the shell (70%). Concerning contamination by combined pathways, at the end of the 21-day exposure, the 4 radionuclides had the same tendency as direct deposition. However, the effect of the trophic pathway was significant: it causes an 18% increase of Sr in the shell and an 7% increase of Cs in the digestive system in comparison to direct deposition, resulting in a final 86% in the shell and 27% in the digestive system.


Subject(s)
Helix, Snails/metabolism , Radioactive Pollutants/metabolism , Radioisotopes/metabolism , Animal Feed , Animals
7.
J Environ Radioact ; 84(3): 417-39, 2005.
Article in English | MEDLINE | ID: mdl-15979215

ABSTRACT

Various types of plants (wheat, bean, lettuce, radish and grass) were contaminated by dry deposition of radioactive aerosols ((137)Cs, (85)Sr, (133)Ba and (123 m)Te) in order to supplement the radio-ecological data necessary for operational post-accidental codes. A few days after deposition, rainfalls were applied to these cultures to evaluate the influence of some characteristics of the rain on the contamination of the culture over time. On the other hand, for wheat and bean, the influence of the humidity condition of the foliage at the contamination time was considered. For a given plant species at a given vegetative stage, the four radionuclides were intercepted in an identical way. The interception varied from 30% for bean (young sprout) to 80% for lettuce (near maturity). The global transfer factor values were dependent on both the radionuclides and the plant species; nevertheless, a higher value was obtained for cesium, regardless of the plant and the rainfall (from 0.006 m(2)kg(fresh)(-1) for wheat-grains - contaminated at the shooting stage - or for bean-pods - contaminated at the pre-flowering stage - to 0.1m(2)kg(fresh)(-1) for a whole lettuce). The analysis of the results allowed us on the one hand, to extract parameter values of the foliar transfer directly usable in operational codes, in particular those relating to barium and tellurium, unknown until then, and on the other hand, to lay the foundations of a future, more mechanistic model, taking into account the foliar processes in a finer way.


Subject(s)
Air Pollutants, Radioactive/analysis , Plants, Edible/chemistry , Radioactive Fallout/analysis , Radioactive Hazard Release , Rain , Aerosols , Barium Radioisotopes/analysis , Cesium Radioisotopes/analysis , Models, Theoretical , Plant Leaves/chemistry , Plant Leaves/growth & development , Plants, Edible/growth & development , Poaceae/chemistry , Poaceae/growth & development , Radioisotopes/analysis , Strontium Radioisotopes/analysis , Tellurium/analysis , Vegetables/chemistry
8.
J Environ Radioact ; 84(1): 1-20, 2005.
Article in English | MEDLINE | ID: mdl-15950331

ABSTRACT

This work is aimed at quantifying foliar transfer of cesium, strontium, barium and tellurium under the influence of rainfall characteristics (intensity, frequency and time elapsed between contamination and first rainfall). Grassland boxes were contaminated by dry deposition of multi-element aerosols of (137)Cs, (85)Sr, (133)Ba and (123m)Te. They were grown in a greenhouse under controlled conditions. The treatments consisted of mowing and applying rainfalls (8 and 30 mmh(-1)) at different times after the contamination. At a leaf area index of 5.9+/-1.9, interception of the aerosols was similar for the 4 radionuclides (83.8+/-5.9%). Dew produced significant radionuclide accumulation in the base of the vegetation and transfer to the soil. For moderate intensity, an early (2 days after contamination) first rainfall was as efficient, in terms of leaf wash-off, as a longer rainfall occurring later (6 days after contamination). For early rainfalls, eliminated activities were comparable because the influence of rain intensity was compensated by rain duration. However, for late rainfalls, wash-off efficiency increased with rainfall intensity. Total transfer factors (TTF) were determined on whole grass immediately after 4 rainfalls and at harvest. After 4 medium intensity rainfalls, rain frequency did not influence total transfer factors (TTF) of strontium, barium and tellurium (about 0.2, 0.3 and 0.35 Bq kg(fresh weight)(-1) by Bq m(-2), respectively). Cesium TTF value was lower in the case of a weekly rain (0.1 against 0.2 Bq kg(fresh weight)(-1) by Bqm(-2)). TTF values were similar for twice-a-week rainfalls, whatever their intensity. They were higher for weekly rains of high intensity (between 0.3 and 0.75 Bq kg(fresh weight)(-1) by Bqm(-2) against 0.1-0.35 Bq kg(fresh weight)(-1) by Bq m(-2), depending on the radionuclides). TTF values attested that wash-off was more efficient when rainfalls lasted longer. Field loss on the top of the leaves was well described by an offset exponential model. The half-lives varied with rainfall characteristics from 4 days for cesium, strontium and barium to 20 days for tellurium. The offset value varied between 0% for tellurium (high intensity rainfalls) and 14% for cesium (medium intensity rainfalls).


Subject(s)
Barium Radioisotopes/pharmacokinetics , Cesium Radioisotopes/pharmacokinetics , Poaceae/metabolism , Rain , Strontium Radioisotopes/pharmacokinetics , Tellurium/pharmacokinetics , Aerosols/pharmacokinetics , Spectrometry, Gamma , Time Factors
9.
J Fr Ophtalmol ; 28(1): 9-16, 2005 Jan.
Article in French | MEDLINE | ID: mdl-15767894

ABSTRACT

PURPOSE: To determine the most efficient diagnostic tools in Vogt-Koyanagi-Harada syndrome, taking into account the international diagnostic criteria, and to evaluate the therapeutic management of these patients. PATIENTS AND METHODS: This study examined patients with a suspicion of VKH syndrome who presented between January 2001 and March 2003, including ocular and extraocular evaluation of the disease at the time of diagnosis. Each patient was classified according to the 1978 international diagnostic criteria and the revised 2001 criteria. In most cases, intravenous steroid pulses were administered. Immunosuppressors were initiated when inflammation was not controlled with steroids. RESULTS: Twenty-two patients were included. The mean age was 33.5 years (range, 15-49 years). Posterior segment involvement, which was observed in 21 patients, depended on the stage of the disease. Anterior segment inflammation was associated in eleven cases. Neurologic symptoms, including meningitis, cerebrospinal fluid lymphocytic pleocytosis, tinnitus, or hearing loss were observed in 12 patients. Fourteen patients had dermatologic signs. Five patients who developed VKH syndrome did not meet the 1978 criteria, and three patients did not meet the 2001 revised criteria. In 19 cases, intraocular inflammation was controlled with corticosteroids. In three cases, corticosteroids could not be discontinued. These patients were treated with immunosuppressive molecules: azathioprine, cyclophosphamide, interferon alpha. At the end of the follow-up period, inflammation was controlled in all patients. DISCUSSION: Revision of the diagnostic criteria provides a more subtle diagnosis of VKH syndrome. However, it is difficult to consider the variability of clinical symptoms during the duration of disease. Corticosteroids must be used at appropriate dosages, followed by slow tapering over 6 months. This attitude seems to reduce the duration of ocular inflammation and decreases the frequency of recurrence. The use of immunomodulating drugs could be reduced by early and appropriate use of systemic steroids. Interferon alpha seems to be a promising alternative in corticoresistant or corticodependent forms of the disease, but further controlled studies are required.


Subject(s)
Uveomeningoencephalitic Syndrome/diagnosis , Uveomeningoencephalitic Syndrome/drug therapy , Adolescent , Adult , Female , Humans , Male , Middle Aged
10.
J Environ Radioact ; 73(1): 49-71, 2004.
Article in English | MEDLINE | ID: mdl-15001295

ABSTRACT

As part of a requirement to improve the assessment of the impact of radioactive fallout on consumed agricultural products, bean plants at four development stages (seedlings, preflowering, late flowering and mature plants) were contaminated by dry deposition of (137)Cs, (85)Sr, (133)Ba and (123m)Te aerosols. The influence of two rain scenarios and of the development stage upon contamination on interception, retention, and translocation to pods was studied. Interception of the four radionuclides was almost identical and varied from 30 to 60% with increasing development stage. The most important rain parameter was the time which elapsed between contamination and the first rain. Whatever the development stage, rain washed off more cesium from the leaves when it occurred 2 days after the deposit (37% at the seedling stage, for example) rather than later on (6 days, 27%), due to rapid migration of Cs in the plant. The first rain washed off nearly 40% of Ba whatever the scenario. For later stages, Sr and Ba were more washed off by heavy weekly rains than by weak twice-a-week rains, perhaps because of the Sr/Ba-contaminated material loss associated with wash off (desquamation of cuticles). Te showed little wash off (less than 5%). Wash off decreased with an older development stage for a weak rain intensity, due to the superimposition of leaves. Heavy rains removed this shelter effect. At harvest, rain effect was no longer detectable as foliar activity was similar for both rain scenarios. Translocation factors (TF) for strontium and barium increased from 6 x 10(-3) to 1 x 10(-1) with the plant development stage upon contamination, whereas those for cesium remained almost unchanged between 2 x 10(-1) and 4 x 10(-1). Flowering is the most critical stage towards residual contamination in pods at harvest, with the exception of direct deposit on pods at the mature stage (TF values are one order of magnitude higher). TF value for Te was 6.5 x 10(-2) and was due to direct deposit. Modelling reflected the trends, through the differential values of the wash off and absorption coefficients, of what was reported for experimental results.


Subject(s)
Air Pollutants, Radioactive/pharmacokinetics , Food Contamination , Phaseolus/chemistry , Radioactive Fallout/analysis , Aerosols , Air Pollutants, Radioactive/analysis , Environmental Monitoring , Flowers , Phaseolus/growth & development , Plant Leaves/chemistry , Rain , Seedlings
11.
Sci Total Environ ; 278(1-3): 199-214, 2001 Oct 20.
Article in English | MEDLINE | ID: mdl-11669268

ABSTRACT

The behaviour of radioactive aerosols released from a severely damaged nuclear reactor and deposited on cereals was simulated under controlled conditions. 137Cs- and 90Sr-labelled aerosols were generated by volatilisation at high temperature of an artificially spiked pellet of depleted UO2. After cooling and maturation the aerosols were allowed to deposit on spring wheat (Triticum aestivum L. var. Arbon) cultures grown on lysimeters under greenhouse conditions. At the time of contamination the wheat plants were at different stages of development, from early vegetative growth (two leaves) until nearly mature (end of flowering). The estimated interception coefficient (micro) amounted to 13.1 m2 kg(-1); such a high value may be explained by the experimental conditions that created an over-saturated atmosphere during the contamination process and wet leaf surfaces. The first simulated rain, applied 6 days after the contamination, removed four times more 137Cs (54%+/-12 of the intercepted radionuclides) than 90Sr (15%+/-20) from the aerial parts. At harvest approximately 2% of the Sr and less than 1% of the Cs initially intercepted by the aerial parts is recovered for plants contaminated during the early development stages. A significantly higher proportion of the intercepted activity is still present for plants contaminated in the late development stages. The translocation to grains (TLF) increases when deposit occurs closer to the mature stage of the plant. The initial decrease of TLF values that we observed for strontium contamination in the earliest development stages is most probably due to the contribution of root uptake. Ploughing and re-sowing after the first rain, applied as a countermeasure reduced the 137Cs content in leaves and stems at harvest approximately 3 times but had no effect on the 90Sr content in vegetative organs. It reduced the 137Cs-contamination level in edible parts (grain) by a factor of 2 compared to the unploughed control, but doubled the 90Sr content.


Subject(s)
Cesium Radioisotopes/pharmacokinetics , Radioactive Hazard Release , Strontium Radioisotopes/pharmacokinetics , Triticum/chemistry , Aerosols , Agriculture , Cesium Radioisotopes/analysis , Environmental Monitoring , Radioactive Fallout , Strontium Radioisotopes/analysis , Tissue Distribution , Water , Weather
12.
J Pharm Sci ; 79(1): 23-7, 1990 Jan.
Article in English | MEDLINE | ID: mdl-2313570

ABSTRACT

Two new methods for the simultaneous determination of chloroquine and its two main metabolites (monodesethylchloroquine and bisdesethylchloroquine) in biological samples, radioimmunoassay (RIA) and enzyme-linked immunosorbent assay (ELISA), are described. Antiserum is produced in rabbits immunized with N-(2-carboxyethyl)desethylchloroquine:protein conjugate. Besides chloroquine, this antiserum recognizes with good affinity the two main metabolites, monodesethylchloroquine and bisdesethylchloroquine (70 and 40% of crossreaction, respectively). Amodiaquine cross reacts by 4.5%; cross reactions with monodesethylamodiaquine, bisdesethylamodiaquine, and other antimalarial drugs are less than 1%. No extraction step or sample preparation is required for either system. Sensitivity limits are, respectively, 0.70 nM (3 pg of chloroquine sulfate measured in 10 microL of plasma sample) for RIA, and 10 nM (22 pg of chloroquine sulfate measured in 5 microL of plasma sample) for ELISA. The interassay coefficients of variation are, respectively, less than 10 and less than 16% for RIA and ELISA in the range 14-410 nM (6-180 ng/mL). The results of both methods are well correlated (r = 0.97) and correlate with spectrophotometry (r = 0.98) and HPLC results (r = 0.93). Because of their high sensitivity, both methods can be used in the case of chloroquine poisoning and in the control of malaria prophylaxis and treatment.


Subject(s)
Chloroquine/analysis , Animals , Chloroquine/analogs & derivatives , Chloroquine/blood , Chloroquine/urine , Enzyme-Linked Immunosorbent Assay , Haptens , Humans , Indicators and Reagents , Iodine Radioisotopes , Polylysine/analysis , Rabbits , Radioimmunoassay , Swine
14.
Ann Dermatol Venereol ; 106(5): 491-4, 1979 May.
Article in French | MEDLINE | ID: mdl-496211

ABSTRACT

We studied a bullous photodermatosis recurring for two years in a old woman. The eruption was diagnosed as a pellagra-like syndrome on tryptophan loading test disorders without any other cause of sun sensitivity. The static and dynamic metabolic investigation was centered on tryptophan and vitaminic coenzymes which mediate catabolic reactions. The defect are located on the kinurenin pathway. The discussion analyses the possible relations between the dermatosis and the biological disturbances observed.


Subject(s)
Kynurenine/metabolism , Photosensitivity Disorders/metabolism , Tryptophan/metabolism , Aged , Animals , Female , Humans , Pellagra/metabolism , Rats
16.
Pathol Biol (Paris) ; 26(7): 453-7, 1978 Oct.
Article in French | MEDLINE | ID: mdl-372901

ABSTRACT

An automated fluorometric method, including norharmane transformation of tryptophan (TRP) by formaldehyde and perhydrol, is applied to free and total TRP determination in human plasma. Separation of free TRP determination in human plasma. Separation of free TRP is achieved by ultrafiltration at pH 7,25 under an air/CO2 flow. The procedure here described is easy, rapid and very sensitive, allowing to work on microsamples if free TRP separation could be realized with them. A correct precision is obtained (CV : 2,8% for plasma repetability) and the specificity is quite good in plasma according to the negligible effect of tryptamine. Frequent values, calculated from 19 healthy subjects are [mean +/- tSE (risk 5%)]:--free TRP : 11,8 +/- 1,5 mumol/l;--total TRP : 52,2 +/- 19,7 mumol/l.


Subject(s)
Tryptophan/blood , Autoanalysis , Humans , Spectrometry, Fluorescence/methods
18.
Ann Biol Clin (Paris) ; 35(5): 387-95, 1977.
Article in French | MEDLINE | ID: mdl-26300

ABSTRACT

Free and total tryptophan is estimated in the plasma by a spectrofluorimetric method using an amplification reaction and fluorescence by transformation of tryptophan into norharman using formalin and perhydrol (fluorescence is amplified about 15 times). Free tryptophan in the plasma is separated by ultrafiltration under pressure. We verified the analytical characteristics of the method in order to obtain optimal conditions. Values frequently found in 16 blood donors in good health were 10.4 +/- 3.3 micronmol/l. for free tryptophan (average +/- ts for a risk of 5%) and 54.6 +/- 18.6 micronmol/l. for total tryptophan.


Subject(s)
Fluorometry/methods , Tryptophan/blood , Depression/blood , Heparin , Humans , Hydrogen-Ion Concentration , Protein Binding , Schizophrenia/blood , Temperature , Tryptophan/analysis , Tryptophan/metabolism , Ultracentrifugation/methods , Ultrafiltration/methods
19.
Encephale ; 2(2): 123-32, 1976.
Article in French | MEDLINE | ID: mdl-6258

ABSTRACT

The dosage of the whole tryptophan and of the free tryptophan was conducted in 16 normal subjects to establish reference values and in 12 schizophrenic subjects among whom 7 were under treatment and 5 were not. The method of dosage is made by spectrofluorimetry by increasing the native fluorescence of tryptophan. The results give mean values for the free tryptophan and for the ratio of the free tryptophan to the whole tryptophan values that are higher in the schizophrenics than in the normal subjects used as reference, while the whole tryptophan seems to be little modified ; this increase is more noticeable in the schizophrenics under treatment. The limited number of the cases studied does not enable us yet to establish correlations between the increase of the free tryptophan found in some cases and the nature of the schizophrenia, its age and its evolutivity or even the clinical response to the treatment. However, some figures for the free tryptophan being very much higher than the mean value in some schizophrenics, suggest ways of research for understanding the pathogenisis of schizophrenia and the mechanisms of the therapeutic action of the psychotropic drugs.


Subject(s)
Schizophrenia/blood , Tryptophan/blood , Adult , Chlorpromazine/therapeutic use , Female , Humans , Lithium/therapeutic use , Male , Middle Aged , Phenothiazines/therapeutic use , Schizophrenia/drug therapy , Spectrometry, Fluorescence
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