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1.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 53(7): 470-474, 2018 Jul 09.
Artigo em Chinês | MEDLINE | ID: mdl-29996365

RESUMO

Objective: To evaluate the remineralization effect and mechanism of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) with different concentrations of fluorine on demineralized enamel using electronic probe. Methods: Extracted premolar teeth for orthodontic purpose were immersed into lactic acid gel to prepare artificial white spot lesions (10 teeth in each group). Then the specimens were randomly assigned to three groups: Control group, with 5% of the CPP-ACP+deionized water; Group A with 5% CPP-ACP+500 mg/L F(-) and Group B with 5% CPP-ACP+900 mg/L F(-). The teeth in each group were soaked in different solutions for 4 days and then were measured using electron probe tester. The changes of contents among the three groups were compared. Results: No statistically significant difference in the percentage of fluorine was found in the control group before and after treatment (P=0.06), and the difference in the percentage of fluorine quality in the other two groups was statistically significant (P<0.05). Statistically significant difference was found between calcium oxide and phosphorus peroxide in the three groups before and after mineralization (P<0.05). The percentage change of fluorine mass in group B [(0.107±0.035)%] was significantly greater than that in group A [(0.057±0.038)%] (P<0.05), while fluorine mass in group A was significantly greater than that in control group [(0.013±0.019)%] (P<0.05). In group A and group B, the change in quality of calcium oxide and phosphorus peroxide was significantly greater than that in control group (P<0.05), while no significant difference was found between group A and group B (P>0.05). Conclusions: The addition of fluorine in CPP-ACP increased the transport and penetration of calcium, phosphorus and fluorine on enamel surface.


Assuntos
Caseínas/farmacologia , Esmalte Dentário/efeitos dos fármacos , Flúor/administração & dosagem , Remineralização Dentária/métodos , Dente Pré-Molar , Cálcio/farmacocinética , Compostos de Cálcio/farmacologia , Assistência Odontológica , Esmalte Dentário/fisiologia , Microanálise por Sonda Eletrônica/métodos , Flúor/farmacocinética , Flúor/farmacologia , Humanos , Óxidos/farmacologia , Fósforo/farmacocinética , Compostos de Fósforo/farmacologia , Distribuição Aleatória
2.
Br Poult Sci ; 42(3): 376-83, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11469559

RESUMO

1. The relative utilisation of different phosphorus sources in relation to their fluorine (F) content was studied in commercial broilers (5 to 40 d) and White Leghorn layers (252 to 364 d). The phosphorus (P) sources tested were bonemeal (BM), low fluorine (LFRP) and high fluorine (HFRP) rock phosphates and a commercial mineral mixture (CMM). The P sources were incorporated in broiler and layer diets by replacing dicalcium phosphate (DCP) on a P basis. 2. The F contents of diets based on BM, LFRP, CMM and HFRP were 53, 365, 622 and 1383 mg/kg in the broiler experiment and 34, 242, 437 and 967 mg/kg in the layer experiment, respectively. F was not detected in DCP based diets. 3. In broilers, body weight gain, food intake, gain: food, P retention and serum inorganic P content on P sources (BM and LFRP) containing F up to 365 mg/kg diet were similar to those on DCP. Body weight gain, food intake, serum calcium and inorganic P contents and retention of P were depressed in groups fed on CMM and HFRP, which may have been due to the toxic effects of F (622 and 1383 mg/kg) present in diets based on these P sources. 4. Bone ash and its P content were not affected by feeding diets containing F up to 1383 mg/kg from various P sources. The amount of F deposited in tibia increased significantly with increases in dietary F concentration. 5. In layers, egg production and food intake were not affected by F up to 437 mg/kg in diets containing BM, LFRP or CMM as the sole source of supplemental P. Egg production and food intake were depressed significantly in layers given the diet containing 967 mg F/kg from HFRP. 6. Egg mass: food, egg weight, shell quality (shell thickness and shell weight) and serum calcium and inorganic P levels were not affected by F up to 967 mg/kg in diets containing different P sources. 7. It may be concluded that the performance of broilers and layers was not affected by feeding various P supplements with dietary levels of F up to 365 and 437 mg/kg, respectively. The reduced performance in broilers and layers observed with some of the P sources may have been due to poor availability of P and/or toxic effects of F (622 and 967 mg/kg, respectively).


Assuntos
Galinhas/metabolismo , Flúor/administração & dosagem , Fósforo na Dieta/metabolismo , Fósforo na Dieta/farmacologia , Animais , Disponibilidade Biológica , Peso Corporal/efeitos dos fármacos , Osso e Ossos/metabolismo , Fosfatos de Cálcio , Relação Dose-Resposta a Droga , Ingestão de Alimentos/efeitos dos fármacos , Feminino , Flúor/farmacocinética , Flúor/farmacologia , Absorção Intestinal/efeitos dos fármacos , Masculino , Oviposição/efeitos dos fármacos , Fósforo na Dieta/administração & dosagem , Distribuição Aleatória
3.
Rocz Panstw Zakl Hig ; 49(3): 341-6, 1998.
Artigo em Polonês | MEDLINE | ID: mdl-9930027

RESUMO

In 65 samples of vegetables: cabbages, carrots, beetroots, onions and potatoes, of whose consumption is the highest in Poland, fluorine content was determined. The samples were prepared according to AOAC method, and fluorine concentration was determined in the filtrate by the potentiometric method using a Fluoride--selective electrode--model 920A of Orion Research Inc. The recovery rate of fluorine was 95 +/- 5%. The average level of soluble fluorine ranged from 3.36 mg/kg of dry weight of cabbage to 5.37 mg/kg of dry weight of onion and from 0.38 mg/kg of fresh weight of cabbage to 1.02 mg/kg of fresh weight of potatoes. In over 50% of the investigated samples fluorine content exceeded 0.56 mg/kg of fresh weight, which is the upper limit value of fluorine content found in the vegetables from the areas ecologically clean.


Assuntos
Flúor/farmacocinética , Marketing de Serviços de Saúde , Solanum tuberosum/metabolismo , Verduras/metabolismo , Humanos , Polônia , Estudos Retrospectivos
4.
Hua Xi Yi Ke Da Xue Xue Bao ; 23(2): 185-9, 1992 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-1452155

RESUMO

Wistar rats were divided into 8 groups:control, 300 ppm F, 130 ppm F, 300 ppm Al, 1200 ppm Al, 130 ppm Al + 130 ppm F. 300 ppm Al + 300 ppm F and 1200 ppm Al + 300 ppm F. The chemicals were mixed into the standard diet. The animals were fed on the diets for 12 weeks. Contents of F, Al, Ca and P in the blood (or serum) and humerus were determined at the end of 12 weeks. The results showed that the level of F in the blood and bone in the unadulterated F group was increased, especially F in the bone reached a level more than 10 times that of the control. In the 3 mixture groups, blood F and bone F were lowered, while blood F was restored to normal level, but bone F was not nevertheless, the results showed that Al was in antagonism to the absorption of F. In the unadulterated Al groups, blood and bone Al did not parallel with the amount of Al administered. The level of Al in the median Al group was higher than that of the high Al group. Taking the level of blood and bone Al as a measure, when different doses of Al were administered with F, in the low and median dosage of Al, F was in antagonism to Al absorption, but in case of high dosage of Al, F was in potentiation to Al absorption. In all the experimental groups serum P was elevated, but serum Ca was not disturbed. Bone Ca and P were decreased only in the 3 groups with unadulterated F as well as unadulterated and adulterated high dosage of Al. Mechanism of the nonlinearity of Al absorption vs Al dosage, as well as the dual effect of F on the absorption of Al was proposed.


Assuntos
Alumínio/farmacocinética , Osso e Ossos/metabolismo , Flúor/farmacocinética , Alumínio/administração & dosagem , Alumínio/sangue , Animais , Cálcio/metabolismo , Interações Medicamentosas , Feminino , Flúor/administração & dosagem , Flúor/sangue , Úmero/metabolismo , Absorção Intestinal , Masculino , Fósforo/metabolismo , Ratos , Ratos Wistar
5.
Rocz Panstw Zakl Hig ; 42(1): 15-23, 1991.
Artigo em Polonês | MEDLINE | ID: mdl-1788508

RESUMO

A literature survey was made of the interactions--in the organism--between some food contaminating elements (mercury, tin, nickel, selenium, fluorine, aluminium) and iron, zinc and copper. The harmful elements may disturb the mineral metabolism already at the stage of intestinal absorption. Moreover, they bring about changes in microelement distribution in the tissues and cells. On account of their approximately similar chemical structure, they compete for the sites of binding to some proteins, including enzymic ones. In this respect a special role is played by ++metallothionein, a protein with the ability of regulating free metal contents in the tissues and thus possibly displaying some detoxifying properties. Many mechanisms and relationships determining the interactions between the surveyed food contaminants and iron, zinc and copper remain, however, not elucidated.


Assuntos
Cobre/farmacologia , Flúor/toxicidade , Contaminação de Alimentos , Ferro/farmacologia , Metais/toxicidade , Selênio/toxicidade , Zinco/farmacologia , Alumínio/antagonistas & inibidores , Alumínio/farmacocinética , Alumínio/toxicidade , Animais , Cobre/metabolismo , Interações Medicamentosas , Flúor/antagonistas & inibidores , Flúor/farmacocinética , Humanos , Ferro/metabolismo , Mercúrio/antagonistas & inibidores , Mercúrio/farmacocinética , Mercúrio/toxicidade , Metais/antagonistas & inibidores , Metais/farmacocinética , Níquel/antagonistas & inibidores , Níquel/farmacocinética , Níquel/toxicidade , Ratos , Selênio/antagonistas & inibidores , Selênio/farmacocinética , Estanho/antagonistas & inibidores , Estanho/farmacocinética , Estanho/toxicidade , Zinco/metabolismo
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