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1.
BMJ ; 302(6792): 1568-71, 1991 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-1906765

RESUMEN

OBJECTIVES: To compare caesium-137 concentrations in patients from the Western Isles Health Board, Glasgow area, and other parts of the Scottish mainland, and to investigate the source of 137Cs in patients from the Western Isles. DESIGN: Study of hypertensive patients having electrolyte concentrations measured, including 137Cs. Interview by questionnaire of island subjects about intake of foods likely to contain radiocaesium and the source of these foods. Measurement of 137Cs and 134Cs in food, urine, and vegetation. SETTING: Scottish mainland and Western Isles, 1979-86. All measurements before Chernobyl nuclear accident. PATIENTS: 413 consecutive patients referred to the blood pressure unit for investigation of hypertension. 60 from the Western Isles, including 44 from North Uist; 32 from North Uist participated in the dietary analysis. MAIN OUTCOME MEASURES: Concentration of radiocaesium in the body, urine, food, and vegetation. Islanders' consumption of local produce. RESULTS: Patients from the Western Isles had five times higher body concentrations of 137Cs (median 2.54 (interquartile range 1.25-3.73)) Bq/gK) than did patients from around Glasgow (0.47 (0.26-0.66) Bq/gK) and other parts of the Scottish mainland (0.42 (0.24-0.71) Bq/gK). Islanders often consumed local milk and mutton, but ate local fish rarely. 137Cs and 134Cs were present in coastal (21.6 Bq/kg 137Cs, 0.25 Bq/kg 134Cs) and moorland (135.9, 0.65 Bq/kg) grasses and in islanders' urine (2.01, 0.013 Bq/l). Lower concentrations (0.336, 0.004 Bq/l), were found in the urine of Glasgow controls (p less than 0.001 for both isotopes). CONCLUSIONS: Islanders have excess body 137Cs concentrations, most of which probably comes from local milk and lamb. The radioactivity is not above the recommended safety limit. The presence of 134Cs suggests that nuclear reprocessing is the source of some of the radiocaesium.


Asunto(s)
Radioisótopos de Cesio/análisis , Adolescente , Adulto , Anciano , Animales , Radioisótopos de Cesio/orina , Dieta , Femenino , Peces , Hébridas , Humanos , Masculino , Persona de Mediana Edad , Leche/química , Poaceae/análisis , Residuos Radiactivos , Escocia , Ovinos , Recuento Corporal Total
4.
Analyst ; 116(4): 391-3, 1991 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1872486

RESUMEN

A sensitive spectrophotometric method for the determination of paraquat using ascorbic acid (an easily available reducing agent) is described. Paraquat is reduced with ascorbic acid in alkaline solution to give a blue radical ion with an absorbance maximum at 600 nm. Beer's law is obeyed in the range 12-96 micrograms of paraquat in 10 ml of the final solution (1.2-9.6 ppm). The important analytical parameters and the optimum reaction conditions were evaluated. The method was applied successfully to the determination of paraquat in water, grain and plant materials.


Asunto(s)
Grano Comestible/análisis , Paraquat/análisis , Plantas/análisis , Espectrofotometría/métodos , Agua/análisis , Ácido Ascórbico , Poaceae/análisis , Solanum tuberosum/análisis
6.
J Anim Sci ; 69(1): 423-8, 1991 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2005036

RESUMEN

Although esophageal extrusa is the most readily accepted representation of forage consumed by grazing ruminants, esophageal sampling is demanding from the standpoint of animal care and maintenance and extrusa processing. This experiment was conducted with a split-plot design to evaluate the effects of pasture type, pasture sampling technique and drying method on estimation of grazed forage composition. Ten esophageally fistulated steers grazed pastures of either tall fescue (Festuca arundinacea Schreb.) or tall fescue interseeded with ladino clover (Trifolium repens L.); steers were closely observed during four collection periods to determine their exact grazing location. Forage samples were collected either directly from the esophageal fistula (E) or hand-gathered (HG) from the immediate perimeter of the grazed area. Samples of E and HG from each steer were divided and oven-dried at 40 degrees C or lyophilized. Fescue samples had lower (P less than .01) N and ADF N concentrations than fescue-ladino clover samples, and E-collected fescue samples had lower (P less than .05) in vitro digestible OM than E-collected fescue-ladino clover samples. Sampling x drying method interactions were detected (P less than .01) for OM, NDF, ADF, hemicellulose (HEMI), ADL, alkaline peroxide lignin (APL), ADFN and indigestible ADF (IADF). Oven-dried E had higher (P less than .05) NDF, ADF, HEMI, ADL, APL and ADF N than lyophilized E; ADF N and IADF were higher from oven-dried HG than from lyophilized HG. In vitro digestible OM was not modified by oven drying. Hand-gathered samples, whether lyophilized or oven-dried, did not simulate E dried by lyophilization. Standardized collection techniques and drying procedures should be implemented to minimize damage to fibrous components.


Asunto(s)
Alimentación Animal/análisis , Bovinos/metabolismo , Esófago/química , Poaceae/análisis , Animales , Digestión , Liofilización , Calor , Masculino , Distribución Aleatoria
9.
Health Phys ; 58(4): 441-52, 1990 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2323926

RESUMEN

Concentrations of radionuclides originating from the Chernobyl reactor accident were measured as a function of time in air, rainwater, grass, cow's milk, vegetables and dust by means of high-resolution gamma-ray spectroscopy. Special attention was paid to grass and milk originating from the same meadows. Also, milk of cows temporarily kept inside after the accident was monitored until a few days after their release from the stables. Activity ratios in various types of samples and the implication of the sheltering measures for cows are discussed.


Asunto(s)
Accidentes , Reactores Nucleares , Ceniza Radiactiva/análisis , Contaminantes Radiactivos del Aire/análisis , Animales , Polvo/análisis , Contaminación Radiactiva de Alimentos/análisis , Leche/análisis , Países Bajos , Poaceae/análisis , Lluvia , Ucrania , Verduras/análisis
10.
Biomed Environ Sci ; 3(1): 81-9, 1990 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2331327

RESUMEN

The present investigation studied the toxicity of soil contaminated by untreated discharge from a factory that recycles used plastics. The nearby agricultural areas and freshwater fish ponds were polluted with high concentrations of Cu, Ni, and Mn. Water extracts from the contaminated soil retarded root growth of Brassica chinensis (Chinese white cabbage) and Cynodon dactylon (Bermuda grass) where their seeds were obtained commercially. The contaminated populations of C. dactylon, Panicum repen (panic grass), and Imperata cylindrica (wooly grass) were able to withstand higher concentrations of Cu, Ni, and Mn, especially C. dactylon, when compared with their uncontaminated counterparts.


Asunto(s)
Plásticos/toxicidad , Poaceae/efectos de los fármacos , Contaminantes del Suelo/toxicidad , Monitoreo del Ambiente , Residuos Industriales/efectos adversos , Residuos Industriales/análisis , Metales/análisis , Poaceae/análisis , Contaminantes del Suelo/análisis
11.
Int Arch Allergy Appl Immunol ; 91(3): 266-9, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2191921

RESUMEN

A microtechnique is described to visualize pollen allergens by making prints from the surface of mature grains on nitrocellulose membrane. The allergen Lol p I is detected by specific monoclonal antibodies or specific IgE from sera of grass-pollen-allergic patients, visualized by the immunoperoxidase method. This technique offers the potential to study the distribution of individual allergens in aerobiology samples by bright-field microscopy, and to determine the sensitivity spectra of allergic individuals to known and unknown pollen sources.


Asunto(s)
Alérgenos , Proteínas de Plantas , Poaceae/análisis , Polen/análisis , Anticuerpos Monoclonales/inmunología , Antígenos de Plantas , Técnicas para Inmunoenzimas , Inmunoglobulina E , Técnicas Inmunológicas
12.
Reprod Nutr Dev ; Suppl 2: 159s-160s, 1990.
Artículo en Francés | MEDLINE | ID: mdl-2206304

RESUMEN

Fiber contents of oven-dried ray-grass cut at different stages of maturity were higher than the values obtained for freeze-dried samples. The reverse was observed for in vitro organic matter digestibility. Moreover, oven-drying dramatically decreased in sacco nitrogen degradability as compared to lyophilization, preservation by freezing with liquid nitrogen and use of fresh material.


Asunto(s)
Alimentación Animal , Nitrógeno/metabolismo , Poaceae , Rumen/metabolismo , Alimentación Animal/análisis , Animales , Manipulación de Alimentos , Técnicas In Vitro , Poaceae/análisis , Ovinos , Factores de Tiempo
14.
J Anim Sci ; 67(12): 3456-62, 1989 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-2693420

RESUMEN

Plant breeders developing cultivars to minimize the hazards of grass tetany are concentrating largely on increasing herbage Mg concentrations in cool-season (C3) grasses. Significant genetic variation has been found for Mg, Ca and K concentrations within C3 grass species studied to date. For most C3 forage grass species, heritability estimates are highest for Mg, slightly lower for Ca and lowest for K concentrations. The largest genotype x environmental interactions are found for K values, whereas small environmental effects have been observed for Mg and Ca values. No C3 forage grass cultivar has been developed to date that would eliminate hypomagnesemia. Grass breeders need to develop more experimental C3 plant populations that have high Mg and Ca concentrations. These experimental synthetics with genetically altered mineral concentrations need to be fed to ruminants susceptible to grass tetany to determine whether grass tetany can be eliminated or reduced. Limited feeding trials using ruminants show that improved animal performance can be expected when feeding forage grasses bred for higher Mg concentrations.


Asunto(s)
Cruzamiento , Deficiencia de Magnesio/veterinaria , Poaceae/genética , Rumiantes , Tetania/veterinaria , Animales , Calcio/análisis , Variación Genética , Genotipo , Magnesio/análisis , Deficiencia de Magnesio/complicaciones , Poaceae/análisis , Potasio/análisis , Tetania/etiología
15.
Boll Soc Ital Biol Sper ; 65(12): 1141-7, 1989 Dec.
Artículo en Italiano | MEDLINE | ID: mdl-2627329

RESUMEN

In this study the amount of glucose, sucrose and fructose was determined in the water soluble fraction while cellulose, hemicellulose, pectin and lignin contents were determined in the alcohol insoluble fraction after hydrolysis. Stalks of sweet sorghum (Sorghum vulgare L., var. saccharatum) cv. Vespa, Soave, Roce and MN 1500 at the physiological ripeness stage were used. The results of the analysis of variance with the least significant difference method (LSD, = 0.05) show that cv. Vespa and Roce have a significantly higher total amount of glucose, fructose and sucrose and at the same time, a lower cellulose, pectin, hemicellulose and lignin content then cv. Soave and cv. MN 1500.


Asunto(s)
Carbohidratos/análisis , Poaceae/análisis , Celulosa/análisis , Fructosa/análisis , Glucosa/análisis , Lignina/análisis , Pectinas/análisis , Sacarosa/análisis
16.
Biol Trace Elem Res ; 22(2): 153-64, 1989 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2484236

RESUMEN

Methylmalonic acid (MMA) concentrations are elevated in plasma as a result of vitamin B12 deficiency. This study reports the sequential changes in plasma MMA in lambs maintained on a cobalt-deficient pasture compared with supplemented controls. The results indicate that MMA is elevated in the early stages of deficiency, preceding the onset of loss of production and clinical signs of disease. It remains elevated as long as the lambs are unsupplemented with cobalt (Co). The most striking clinical sign was a loss of body condition as opposed to weight. The defect in the methylmalonyl CoA mutase is obviously an early defect in cobalt deficiency.


Asunto(s)
Cobalto/deficiencia , Malonatos/sangre , Ácido Metilmalónico/sangre , Poaceae/análisis , Vitamina B 12/sangre , Animales , Peso Corporal/efectos de los fármacos , Dieta , Ovinos , Deficiencia de Vitamina B 12/sangre
17.
Sci Total Environ ; 85: 129-38, 1989 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2814440

RESUMEN

The transfer of Cs137 from grass and silage to milk has been followed in detail for one farm in West Cumbria over the year following the deposition from the Chernobyl reactor accident. At this farm about 40% of the Cs137 in milk was attributed to the feeding of silage during the following winter. A wider study of an additional 14 farms showed considerable variations in the contributions from grazing and silage. The transfer quotient from silage to milk was comparable with the values measured for grass over the first few weeks and lower than values reached later in the grazing season.


Asunto(s)
Alimentación Animal , Radioisótopos de Cesio , Contaminación Radiactiva de Alimentos/análisis , Leche/análisis , Accidentes , Adulto , Alimentación Animal/análisis , Animales , Bovinos , Radioisótopos de Cesio/análisis , Niño , Femenino , Humanos , Lactante , Modelos Biológicos , Reactores Nucleares , Poaceae/análisis , Ensilaje/análisis
18.
Sci Total Environ ; 85: 139-47, 1989 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2814441

RESUMEN

Deposition of radiocaesium from the Chernobyl reactor accident on the Netherlands made it possible to collect contaminated fresh grass and first cut wilted grass silage. These contaminated roughages were used in transfer experiments with lactating dairy cows to determine transfer coefficients and half-lives for Cs-137 in milk. The experimental design was based on three consecutive periods: a preliminary period to determine the background concentration of the isotope in milk, a contamination period to determine the magnitude of accumulation and finally a depletion period to measure the rate at which the activity concentration of Cs-137 in milk declined after continuous feeding. The average transfer coefficient (Fmilk) for cows fed on contaminated dried grass under steady-state conditions was 0.002 d/kg and for cows fed on slightly contaminated second cut fresh grass 0.006 d/kg. The highest transfer coefficients were obtained for cows fed on contaminated grass silage for 119 days, which also included the dry period of about two months. For the first five days after calving the Fmilk values varied from 0.0066 to 0.0091 d/kg. There were no significant differences in transfer coefficients between cows in early lactation (third month of lactation), cows in late lactation (the last month of the lactation period) and cows fed on both contaminated grass silage and uncontaminated maize silage simultaneously. Half-life values for the rate of decline of the isotope in milk during the depletion period were estimated on the basis of a mathematical model with two exponential components. These components were characterized by half-lives of 0.5 to 3.5 days and 10 to 46 days.


Asunto(s)
Accidentes , Alimentación Animal/análisis , Radioisótopos de Cesio/análisis , Contaminación Radiactiva de Alimentos/análisis , Leche/análisis , Reactores Nucleares , Animales , Bovinos , Femenino , Semivida , Países Bajos , Poaceae/análisis , Ensilaje/análisis , Ucrania
19.
Sci Total Environ ; 85: 169-77, 1989 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2814444

RESUMEN

From February to October 1987 samples of milk, grass and other components of the cow diet were regularly collected and analyzed for their radiocaesium contents in 26 sampling stations in a north-eastern region of Italy (Friuli-Venezia Giulia). In this paper we report the feed-to-milk transfer factors for radiocaesium obtained in 13 farms of this region of Italy.


Asunto(s)
Accidentes , Alimentación Animal/análisis , Bovinos , Radioisótopos de Cesio/análisis , Contaminación Radiactiva de Alimentos/análisis , Leche/análisis , Reactores Nucleares , Radioisótopos de Potasio/análisis , Ceniza Radiactiva , Animales , Femenino , Italia , Poaceae/análisis , Ensilaje/análisis , Factores de Tiempo , Ucrania
20.
Sci Total Environ ; 85: 179-88, 1989 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2814445

RESUMEN

The transfer of Chernobyl Cs-134 and Cs-137 to milk in dairy cows from a diet, predominated by silage, was studied under normal farming conditions. The study was carried out in the period December 1986 till August 1987 and comprised three periods with different levels of radioactive contamination of the silage. Transfer coefficients for both radionuclides were derived from measured radiocaesium concentrations in the diet components and in mixed milk samples. Average silage intake was calculated on basis of total need which depends on milk production. The transfer coefficients calculated for Cs-134 and Cs-137 after a 6 weeks feeding period of high-level post-Chernobyl silage were 0.26 and 0.27% d/l, respectively. These results indicate that a transfer coefficient of 1.2% d/l, from tracer and fallout studies and recommended for predictive purposes, is a conservative estimate in view of the post-Chernobyl experience. The transfer of caesium isotopes from silage to milk in dairy cows is dynamically described with a simple two-compartment model of Pelletier and Voilleque. The most important choices of parameter values to be made in matching calculated and measured concentrations in milk, are those for F and u/m. F is the fraction of ingested activity that is excreted in milk plus urine, and u/m is the ratio between the transfer rates to urine and milk, respectively. The study was carried out with financial support from the Dutch Ministry of Agriculture and Fishery.


Asunto(s)
Accidentes , Alimentación Animal/análisis , Radioisótopos de Cesio/análisis , Contaminación Radiactiva de Alimentos/análisis , Leche/análisis , Reactores Nucleares , Ceniza Radiactiva , Animales , Bovinos , Femenino , Países Bajos , Poaceae/análisis , Ensilaje/análisis , Factores de Tiempo , Ucrania
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