Resultado da pesquisa (4)

Termo utilizado na pesquisa Fluoride

#1 - Metabolismo e distribuição do flúor em ovinos jovens tratados cronicamente com fluoreto de sódio, p.124-128

Abstract in English:

ABSTRACT.- Filappi A.R., Prestes D.S., Antes F.G., Flores E.L.M., Dressler V.L., Flores E.M.M. & Cecim M. 2008. [Metabolism and distribution of fluor in lambs chronically treated with sodium fluoride.] Metabolismo e distribuição do flúor em ovinos jovens tratados cronicamente com fluoreto de sódio. Pesquisa Veterinária Brasileira 28(2):124-128. Departamento de Clínica de Grandes Animais, Universidade Federal de Santa Maria, Campus Camobi, Santa Maria, RS 97105-900, Brazil. E-mail: afilappi@bol.com.br The objective of the present study was to evaluate fluorine metabolism in growing lambs. Twelve 5-month-old male lambs maintained on alfalfa hay (3% BW) and non-fluorinated water ad libitum were used. Animals were allocated into Control, receiving 5g NaCl/animal/day + 0.2mg I/kg dry matter) and Treated group, receiving the same treatment plus sodium fluoride (4.7mg F/kg body weight). Mineral treatment was given by gavage, daily for 150 days. Blood, urine and fecal samples were collected during and the end of the experiment. At the end of treatment period animals were euthanized and kidney, pineal and bone samples were collected. Urine F was higher in treated animals throughout the experiment. Bone F levels were also increased in treated animals; pineal F content however, was not different between groups. Kidney histology revealed no differences. It is concluded that chronic F administration induces accumulation of the element in the skeleton. However such fact appears not to be detrimental to animals. Rates of F accumulation in bone and urine excretion obtained in other species can not be used in growing lambs.

Abstract in Portuguese:

ABSTRACT.- Filappi A.R., Prestes D.S., Antes F.G., Flores E.L.M., Dressler V.L., Flores E.M.M. & Cecim M. 2008. [Metabolism and distribution of fluor in lambs chronically treated with sodium fluoride.] Metabolismo e distribuição do flúor em ovinos jovens tratados cronicamente com fluoreto de sódio. Pesquisa Veterinária Brasileira 28(2):124-128. Departamento de Clínica de Grandes Animais, Universidade Federal de Santa Maria, Campus Camobi, Santa Maria, RS 97105-900, Brazil. E-mail: afilappi@bol.com.br The objective of the present study was to evaluate fluorine metabolism in growing lambs. Twelve 5-month-old male lambs maintained on alfalfa hay (3% BW) and non-fluorinated water ad libitum were used. Animals were allocated into Control, receiving 5g NaCl/animal/day + 0.2mg I/kg dry matter) and Treated group, receiving the same treatment plus sodium fluoride (4.7mg F/kg body weight). Mineral treatment was given by gavage, daily for 150 days. Blood, urine and fecal samples were collected during and the end of the experiment. At the end of treatment period animals were euthanized and kidney, pineal and bone samples were collected. Urine F was higher in treated animals throughout the experiment. Bone F levels were also increased in treated animals; pineal F content however, was not different between groups. Kidney histology revealed no differences. It is concluded that chronic F administration induces accumulation of the element in the skeleton. However such fact appears not to be detrimental to animals. Rates of F accumulation in bone and urine excretion obtained in other species can not be used in growing lambs.


#2 - Histomorphometricand histological evaluations of the bone lesions caused by fluoride in chickens

Abstract in English:

Sodium fluoride was administered in the water to 2 groups of 25 Shaver female poultry. Group A received fluoride from 1 to 120 days of age and group B from 61 to 120 days. Each group was divided into 5 treatments, with 5 chickens each, which received 0, 25, 50, 200, and 400 ppm of fluoride in the water, respectively. AII animals were killed at 120 days of age. For histomorphometric studies the left femur and tibia were used, and for histologic studies the right femur and tibia. In the cortical bone, cortical porosity was slightly increased by fluoride, but the differences with the control group were not significant. Cortical thickness increased in the animals treated with fluoride (p<0,05, r2 = 0,59 ). In the trabecular bone, of group A, trabecular thickness (TT) (p<0,05, r2 = 0,63) and trabecular bone volume (TBV) (p<0,05, r2 = 0,72) increased in treatments receiving 25-200 ppm, and decreased in the 400 ppm treatment, as it was demonstrated by quadratic regression analysis. In group B there was a positive linear correlation on TT (p<0,05, r2 = 0,98) and TBV (p<0,05, r2 = 0,77) with fluoride ingestion.The osteoid surface was also positively correlated with the amount of fluoride ingested by the animals (p<0,001, r2 = 0,80). These results suggest that fluoride improves osteoblastic function resulting in increased osteoid production and bone apposition. In the other hand, in the animals treated with 400 ppm of fluoride for 120 days bone apposition was reduced suggesting a functional alteration of the osteoblasts or improved bone resorption. In the histological study of bone tissue all animals that received fluoride showed an increased trabecular thickness which was more marked in the 200-400 ppm treatments. In chickens treated with 200-400 ppm of fluoride osteoblasts and osteoclasts were more numerous suggesting an increased bone turnover. In cortical bone Haversian canais were narrowed on the periosteal surfaces and resorption spaces were enlarged on the endosteal surfaces.

Abstract in Portuguese:

Fluoreto de sódio foi administrado na água de 2 grupos de 25 aves, fêmeas, da raça Shaver. O grupo A recebeu flúor do 1° ao 120° dia de idade e o grupo B do 61° ao 120º dia de idade. Cada grupo foi dividido em 5 níveis de tratamento: 0, 25, 50, 200 e 400 ppm de flúor, com 5 animais por tratamento. Todos os animais foram sacrificados aos 120 dias de idade. Para o estudo histomorfométrico foram coletados o fêmur e a tíbia esquerdos, e para o estudo histológico foram coletados fêmur e tíbia direitos. No estudo histomorfométrico do osso compacto observou-se um discreto aumento da porosidade cortical, que não foi estatisticamente significativo. A espessura do osso cortical aumentou nos animais tratados com flúor (p<0,05, r2 = 0,59). No osso trabeculai; do grupo A, houve um aumento da espessura trabecular (ET) (p<0,05, r2 = 0,63) e do volume trabecular ósseo (VTO) (p<0,05, r2 = 0,72) até a dose de 200 ppm; e, na dose de 400 ppm, ocorreu um decréscimo, demonstrado pela regressão quadrática obtida na análise de regressão. No grupo B houve um aumento progressivo da ET (p<0,05, r2 = 0,98) e do VTO (p<0,05, r2 = 0,77) diretamente relacionado com a dose de flúor. A superfície de osteóide (SO) apresentou, também, um aúmento gradativo relacionado com a dose, nos animais tratados com flúor (p<0,001, r2 = 0,80). Esses resultados sugerem que o flúor estimula a função osteoblástica, resultando em aumento da SO, e consequentemente maior aposição óssea. No entanto, nos animais tratados com 400 ppm, durante 120 dias, esse estímulo sobre a aposição óssea não foi tão evidente, sugerindo que o flúor determina alguma alteração funcional sobre os osteoblastos ou um aumento da reabsorção óssea. Histologicamente, observou-se espessamento trabecular nos animais tratados com flúor, mais marcado nas doses de 200 e 400 ppm, em ambos os grupos. Sobre a superfície trabecular, dos animais tratados com 200 e 400 ppm, evidenciou-se, principalmente, osteoblastos ativos e osteoclastos, sugerindo um aumento da remodelação óssea. No osso cortical observou-se diminuição dos canais de Havers, próximos a superfície periosteal, e aumento das lacunas de reabsorção próximas a superfície endosteal.


#3 - Dental lesions in cattle and sheep due to industrial pollution caused by coal combustion

Abstract in English:

Diverse dental lesions were verified on 11 farms located between 1.2 and 9.6 km from a coal-combustion thermoelectric plant in the municipality of Bagé, Rio Grande do Sul, Brazil. The incisor teeth of some animals appeared opaque with white spots, yellowishbrown discoloration and hypoplasia of the enamel. Gingival hyperplasia was also seen. These lesions were numerous on the farms close to the plant and less frequent on those more distant. The most important alteration was dental wear. Incisor teeth of cattle from farms near the plant were completely worn down by the time the animals were six to seven years of age; the degree of wear was related to the distance between the farms and the plant as a linear function [Y = 4.11 + (- 0.42x); r2 = 0.75 (P < O.OS)]. Histological lesions of permanent incisors were characterized by hyperplasia of the cernentum, proliferation of the dentin, and periodontal pocketing with alveolar bone resorption. Excessive and irregular wear was also observed in prernolar and molar teeth. Sheep presented lesions similar to those observed in cattle; ewes three to four years old showed completely worn down incisors. Fluoride levels in cattle on a farm located 2.45 km from the plant varied from 1091 to 5673 ppm (X̅ = 2539 ppm) in nine humerus bones and from 389 to 2931 ppm (X̅ = 1346 ppm) in 21 mandibles. These levels decreased as the distance from the plant increased; on a farm 7.5 km away, fluoride levels were 386 ppm in humerus bones and 265 ppm in mandibles. The results obtained confirm the diagnosis of fluoride poisoning, a condition that was previously described in the city of Rio Grande, Rio Grande do Sul, and attributed to pollution cause d by phosphate processing factories. In the Candiota region the enamel lesions were less pronounced and the fluoride levels lower than those observed in Rio Grande, however, the dental wear was much more accentuated in the animals from Candiota. Two factors might be responsible for this dental wear: the abrasive effect of particles eliminated into the air during coal combustion, the most important of which appears to be silica; and the decrease in the resistance of the enamel as a consequence of fluoride poisoning.

Abstract in Portuguese:

Diversas lesões dentárias foram constatadas em 11 propriedades localizadas entre 1,2 e 9,6 km de urna usina termoelétrica no município de Bagé, Rio Grande do Sul. Os dentes incisivos de alguns animais apresentavam-se opacos, com manchas brancas, pigmentação amarelo-marrom, hipoplasia do esmalte. Hiperplasia da gengiva também ·foi observada. Tais lesões eram consideráveis nos estabelecimentos mais próximos da usina e discretas nos demais. A alteração mais importante era o desgaste dentário. Os bovinos dos estabelecimentos mais próximos da usina apresentavam desgaste completo dos seus incisivos aos 6 ou 7 anos de idade; o grau de desgaste esteve relacionado à distância entre os estabelecimentos e a usina como uma função linear Y = 4,11 + (- 0,42. x); r2 = 0,75 (P < 0,05). As lesões histológicas dos incisivos permanentes foram caracterizadas por hiperplasia do cemento, proliferação de dentina reacional, e formação de bolsa peridentária com reabsorção do osso alveolar. Desgaste excessivo e irregular foi observado também em dentes premolares e molares. Os ovinos apresentaram lesões similares às dos bovinos; ovelhas de 3 à 4 anos de idade apresentavam desgaste total de seus incisivos. Os níveis de flúor em bovinos, em um estabelecimento situado a 2,45 km da usina variaram de 1091 a 5673 ppm (X̅ = 2539 ppm) em nove úmeros e de 389 a 2931 ppm (X̅= 1346 ppm) em 21 mandíbulas. Os níveis de flúor diminuíram a medida que aumentava a distância da usina; em um estabelecimento situado a 7 ,5 km os níveis foram de 386 ppm em úmero e 265 ppm em mandíbula. Os resultados obtidos confirmam o diagnóstico de intoxicação por flúor, doença que foi diagnosticada anteriormente no município de Rio Grande, RS, como conseqüência da poluição causada por fábricas de adubo. Na região de Candiota as lesões do esmalte são menos pronunciadas e os níveis de flúor mais baixos que os observados em Rio Grande; o desgaste dentário, no entanto, é muito mais acentuado nos animais de Candiota. Dois fatores seriam responsáveis pelo desgaste dentário: o efeito abrasivo dos particulados eliminados com o efluente da combustão de carvão, dos quais o mais importante pareceria ser o silício; a diminuição da resistência do esmalte como conseqüência da intoxicação por flúor.


#4 - Industrial pollution as a cause of fluoride intoxication in cattle in the municipality of Rio Grande, southern Brazil

Abstract in English:

Fluoride intoxication in cattle occurred as a consequence of atmospheric pollution caused by the industrial effluents of 4 phosphate processing factories located in the city of Rio Grande, state of Rio Grande do Sul. The lesions of the incisor teeth were characterized by a chalky white or brown discoloration, hypoplasia of the enamel, increased attrition and gingival hyperplasia. Such lesions were studied in animals from 19 farms loca te d in a range of 4 .5 to 17 .5 km from the factories. The severity of the lesions was related to the distance between the farms and the factories as a linear function [Y = 2.13 + (- 0.12. x); r2 = 0.77 (P < 0.001)]. Molar and premolar teeth showed excessive and uneven attrition. In a farm located 6 km from the factories, 2 cows showed lameness and 1 had hyperostosis of the metatarsal bones. Histological lesions of the permanent incisor teeth were hyperplasia of the cement and disturbed incremental lines and hypocalcification of the dentine. Bone lesions were characterized by osteoporosis with degeneration and atrophy of osteoblasts. Numerous cementing lines and retention of the chondroid core were observed, indicating arrested osteocytic osteolysis and chondrolysis. In compact bone, osteons were irregular in shape, size and distribution with enlarged Haversian canals and irregular distribution of osteocytes; insterstitial lamellae were increased and irregular. It is considered that the lesions of osteofluorosis are due to an imbalance between bone apposition and resorption; osteoporosis would be a result of the alterations observed in osteoblastos which were apparently more severely affected than osteocytes. Fluoride leveis, determined in the epifise-metafise of the humerus of 3 animals and in the mandibles of 7 belonging to two properties situated between 5 and 6 km from the factories, varied between 1,400 ppm and 5,750 ppm of ash. This paper points out the potential risks of fluoride contamination by the human population of the city of Rio Grande, where the fosfate processing factories are situated.

Abstract in Portuguese:

Descreve-se intoxicação por flúor, em bovinos, como conseqüência da poluição atmosférica produzida por fábricas de adubo que processam rocha fosfática, localizadas na cidade de Rio Grande, Rio Grande do Sul. As lesões dos· incisivos caracterizaram-se por manchas esbranquiçadas com aspecto de giz, pigmentação marrom, hipoplasia do esmalte, desgaste dentário exagerado e hiperplasia da gengiva. Tais lesões foram estudadas em 19 estabelecimentos localizados entre 4,5 e 17 ,5 km de distância das fábricas de adubo, determinando-se uma função linear do grau das lesões com relação à distância [Y = 2,13 + (-0,12 . x); r2 = 0,77 (P < 0.001)]. Os molares e pré-molares apresentaram desgaste excessivo e irregular. Em um estabelecimento, localizado a 6 km das fábricas, foram observadas lesões de hiperostose em um animal, e claudicação em dois. Histologicamente as lesões dentárias foram caracterizadas por hiperplasia do cemento assim como distúrbios das linhas incrementais e hipocalcificação da dentina. As lesões ósseas consistiram em osteoporose com atrofia e degeneração dos osteoblastos; foram observadas também retenção da corda condróide e presença de linhas cimentantes, evidenciando uma inibição da condrólise e osteólise osteocítica. No osso compacto, os sistemas de Havers apresentavam-se irregulares em seu tamanho, forma e distribuição, os canais de Havers estavam aumentados de diâmetro e os osteócitos irregularmente distribuídos dentro do sistema; as lamelas intersticiais estavam aumentadas e irregulares. Considera-se que as alterações ósseas foram produzidas por um desequilibrio entre a aposição e a reabsorção óssea. A osteoporose teria ocorrido como consequência das lesões dos osteoblastos, os quais foram aparentemente mais afetados que os osteócitos. Os níveis de flúor, determinados em 7 mandíbulas e 3 úmeros de animais pertencentes a dois estabelecimentos situados entre 5 e 6 km das fábricas, variaram entre 1.400 e 5 .750 ppm. Alerta-se para os riscos de saúde, pela contaminação por flúor, a que estão expostos os habitantes da cidade de Rio Grande, onde se localizam as fábricas processadoras de rocha fosfática.


Colégio Brasileiro de Patologia Animal SciELO Brasil CAPES CNPQ UNB UFRRJ CFMV