RESUMO
Cassava flour is the main dietary carbohydrate source in the Amazonian region. The cariogenic potentials of the two main kinds of cassava flour - 'seca' and 'd'água' - were evaluated in vivo and in vitro. A sweet made from a regional fruit (cupuaçú) and a species of local fish (tambaqui) were used as positive and negative controls, respectively. For in vivo evaluation of dental plaque acidogenicity, the study had a crossover design, in four legs, with 19 volunteers in four treatment groups. Dental plaque pH was determined by the microtouch method before and for 60 min after food consumption. For in vitro evaluation, stimulated saliva of each volunteer was incubated with the food and pH variation was determined over 4 h. Carbohydrates were chemically determined in the flours and the majority was found to be water-insoluble. In vivo, plaque pH decreased significantly after the consumption of the sweet (p < 0.05), increased after the fish (p < 0.05), but did not change after intake of the flours (p > 0.05). In vitro, the flours were slowly fermented by bacteria present in saliva. The in vivo and in vitro findings suggest that, in the form that the main cassava flours from the Amazonian region of Brazil are customarily eaten, they may be considered to have no or very low cariogenicity.
Assuntos
Cariogênicos , Placa Dentária/química , Farinha , Manihot , Adulto , Análise de Variância , Brasil , Cariogênicos/efeitos adversos , Cariogênicos/química , Estudos Cross-Over , Carboidratos da Dieta/análise , Farinha/efeitos adversos , Farinha/análise , Manipulação de Alimentos , Humanos , Concentração de Íons de Hidrogênio , Manihot/efeitos adversos , Manihot/química , Raízes de Plantas/efeitos adversos , Raízes de Plantas/química , Saliva , SolubilidadeRESUMO
Cassava flour is the main dietary carbohydrate source in the Amazonian region. The cariogenic potentials of the two main kinds of cassava flour - `seca` and `d`água` - were evaluated in vivo and in vitro. A sweet made from a regional fruit (cupua;ú) and a species of local fish (tambaqui) were used as positive and negative controls, respectively. For in vivo evaluation of dental plaque acidogenicity, the study had a crossover design, in four legs, with 19 volunteers in four treatment groups. Dental plaque pH was determined by the microtouch method before and for 60 min after food consumption. For in vitro evaluation, stimulated saliva of each volunteer was incubated with the food and pH variation was determined over 4 h. Carbohydrates were chemically determined in the flours and the majority was found to be water-insoluble. In vivo, plaque pH decreased significantly after the consumption of the sweet (p < 0.05), increased after the fish (p < 0.05), but did not change after intake of the flours (p > 0.05). In vitro, the flours were slowly fermented by bacteria present in saliva. The in vivo and in vitro findings suggest that, in the form that the main cassava flours from the Amazonian region of Brazil are customarily eaten, they may be considered to have no or very low cariogenicity
Assuntos
Placa Dentária , Dieta Cariogênica , Concentração de Íons de HidrogênioRESUMO
The composition of dental plaque formed in the presence of sucrose or glucose and fructose and its relation to cariogenicity was evaluated. Twelve adult volunteers took part in this crossover study done in three phases of 28 days each. For each phase, an acrylic resin appliance containing four human dental enamel blocks was constructed for the volunteers. Solutions containing 20% sucrose or 10% glucose + 10% fructose were dripped onto the enamel blocks 8 times a day, while in the control group no solution was used. Enamel surface and cross-sectional microhardness results showed that dental plaque formed in the presence of sucrose was more cariogenic than that formed in the presence of glucose + fructose (p<0.05). The concentration of alkali-soluble carbohydrates in dental plaque was higher in the sucrose group than in the control and glucose + fructose groups (p<0.05). Although concentrations of Ca, P and F were lower in plaque formed in the presence of sucrose than glucose + fructose and the control, significant differences (p<0.05) were only observed in relation to control. The electrophoretic profile of the matrix proteins of dental plaque showed distinct patterns when it was formed in the absence or presence of the different carbohydrates. Although the results suggest that the high cariogenicity of dental plaque formed in the presence of sucrose can be mainly explained by the high concentration of insoluble glucans of its matrix, the low inorganic concentration and its protein composition may have some contribution.
Assuntos
Cariogênicos/química , Placa Dentária/química , Frutose/metabolismo , Glucose/metabolismo , Sacarose/metabolismo , Resinas Acrílicas , Adulto , Álcalis/química , Cálcio/análise , Cariogênicos/metabolismo , Estudos Cross-Over , Esmalte Dentário/química , Esmalte Dentário/metabolismo , Esmalte Dentário/patologia , Placa Dentária/etiologia , Placa Dentária/metabolismo , Fluoretos/análise , Glucanos/análise , Dureza , Humanos , Fósforo/análise , Proteínas/análise , Método Simples-Cego , Solubilidade , Estatísticas não ParamétricasRESUMO
Hypocitraturia (HCit) is one of the most remarkable features of renal tubular acidosis, but an acidification defect is not seen in the majority of hypocitraturic patients, whose disease is denoted idiopathic hypocitraturia. In order to assess the integrity of urinary acidification mechanisms in hypocitraturic idiopathic calcium stone formers, we studied two groups of patients, hypocitraturic (HCit, N = 21, 39.5 +/- 11.5 years, 11 females and 10 males) and normocitraturic (NCit, N = 23, 40.2 +/- 11.7 years, 16 females and 7 males) subjects, during a short ammonium chloride loading test lasting 8 h. During the baseline period HCit patients showed significantly higher levels of titratable acid (TA). After the administration of ammonium chloride, mean urinary pH (3rd to 8th hour) and TA and ammonium excretion did not differ significantly between groups. Conversely, during the first hour mean urinary pH was lower and TA and ammonium excretion was higher in HCit. The enhanced TA excretion by HCit during the baseline period and during the first hour suggests that the phosphate buffer mechanism is activated. The earlier response in ammonium excretion by HCit further supports other evidence that acidification mechanisms react promptly. The present results suggest that in the course of lithiasic disease, hypocitraturia coexists with subtle changes in the excretion of hydrogen ions in basal situations.
Assuntos
Acidose Tubular Renal/metabolismo , Ácido Cítrico/urina , Cálculos Urinários/urina , Acidose Tubular Renal/etiologia , Adulto , Cloreto de Amônio/urina , Estudos de Casos e Controles , Feminino , Humanos , Concentração de Íons de Hidrogênio , Litíase/complicações , Masculino , Organofosfatos/urina , Fatores de TempoRESUMO
Hypocitraturia (HCit) is one of the most remarkable features of renal tubular acidosis, but an acidification defect is not seen in the majority of hypocitraturic patients, whose disease is denoted idiopathic hypocitraturia. In order to assess the integrity of urinary acidification mechanisms in hypocitraturic idiopathic calcium stone formers, we studied two groups of patients, hypocitraturic (HCit, N = 21, 39.5 + or - 11.5 years, 11 females and 10 males) and normocitraturic (NCit, N = 23, 40.2 + or - 11.7 years, 16 females and 7 males) subjects, during a short ammonium chloride loading test lasting 8 h. During the baseline period HCit patients showed significantly higher levels of titratable acid (TA). After the administration of ammonium chloride, mean urinary pH (3rd to 8th hour) and TA and ammonium excretion did not differ significantly between groups. Conversely, during the first hour mean urinary pH was lower and TA and ammonium excretion was higher in HCit. The enhanced TA excretion by HCit during the baseline period and during the first hour suggests that the phosphate buffer mechanism is activated. The earlier response in ammonium excretion by HCit further supports other evidence that acidification mechanisms react promptly. The present results suggest that in the course of lithiasic disease, hypocitraturia coexists with subtle changes in the excretion of hydrogen ions in basal situations
Assuntos
Humanos , Masculino , Feminino , Adulto , Acidose Tubular Renal/metabolismo , Ácido Cítrico/urina , Cálculos Urinários/urina , Acidose Tubular Renal/etiologia , Acidose Tubular Renal/fisiopatologia , Cloreto de Amônio/farmacocinética , Cloreto de Amônio/urina , Concentração de Íons de Hidrogênio , Litíase/complicações , Organofosfatos/urina , Fatores de TempoRESUMO
PURPOSE: To divulge information on the chemical composition and physical-chemical features of some mineral waters from Brazilian natural sources that will be of useful protocol investigation and patient advice. METHODS: The survey was based on bottle labels of non-gaseous mineral waters commercially available in the city of Rio de Janeiro. The íon concentration of each mineral was calculated from the salt content. RESULTS: 36 springs were enralled from different states of the country. The pH (25 degrees C), 4.1 to 9.3, varied on dependence of the source and it was linearey correlated with the cations calcium, magnesium and sodium and the anion bicarbonate. It was atributed to high alkalinity (about 70% of bicarbonate in the molecula-gram) of these salts. The calcium (0.3 to 42 mg/l), magnesium (0.0 to 18 mg/l) and bicarbonate (4 to 228 mg/l) contents are relatively low. CONCLUSION: The mineral content of the Brazilian springs enrolled in this survey is low; about 70% of the sources having calcium and magnesium less than 10 mg/l and 1.0 mg/l, respectively, similar to local tap water.
Assuntos
Águas Minerais/análise , BrasilRESUMO
Paciente de litíase renal é estimulado a aumentar a ingestão hídrica, principalmente na forma de água tratada da torneira, pela irrelevante biodisponibilidade de mineerais em sua composição. O benefício é atribuído à redução da saturação dos sais urinários. Não está claro se as águas minerais naturais comercialmente disponíveis também é benéfica. Objetivo. Divulgar as informações sobre as características químicas e físico-químicas de águas minerais naturais de algumas das diversas fontes brasileiras. Essas informações serão de utilidade na análise de protocolos de pesquisa e na orientação do paciente. Métodos. Foi feito uma coletânea das informações que constam nos rótulos de garrafas de águas minerais naturais, predominantemente não-gasosas, acessíveis ao consumo carioca. A partir da composição salina provável, foi calculada a concentração iônica de cada mineral. Resultados. Foram estudadas as informações de 36 fontes situadas em alguns estados brasileiros. O pH, a 25 graus Celsius, variou de 4,1 a 9,3 na dependência da fonte e foi linearmente correlacionando com as concentrações dos cátions cálcio, magnésio, sódio e do anion bicarbonato. Isto foi atribuído à alta alcalinidade desses sais, que contêm cerca de 70 por cento de bicarbonato na molécula. Os teores de cálcio (0,3 a 42 mg/l), de magnésia (0,0 a 18 mg/l) e de bicarbonato (4 a 228 mg/l) foram considerados relativamente baixos. Conclusão. O teor mineral das fontes brasileiras que compuseram esse levantamente é baixo, com cerca de 70 por cento delas apresentando teores de cálcio e de magnésio abaixo de 10 mg/l e 1 mg/l, respectivamente, semelhantes ao da água tratada da torneira.