Virginia L. Hood

The Use of Magnesium-Containing Phosphate Binders in Patients with End-Stage Renal Disease on Maintenance Hemodialysis

We investigated the safety and efficacy of magnesium hydroxide as a phosphate binder in patients with end-stage renal disease on maintenance hemodialysis, 9 volunteers participated in a four-phase study during which each ingested (1) no phosphate binders, (2) magnesium hydroxide (Mg(OH)2) alone, (3) Mg(OH)2 and aluminum hydroxide (A1(OH)3) together and (4) A1(OH)3 alone. Serum magnesium (SMg) concentrations were maintained at less than 4.5 mEq/1 (2.3 mmol/l) in all subjects while they were ingesting 0.75-3 g Mg(OH)2/day and no magnesium toxicity was noted. In individuals taking a constant daily dose, SMg remained stable over 8-12 weeks. Serum phosphorus (SP) decreased from 9.0 mg/dl (2.9 mmol/l)d during the control period to 8.1 mg/dl (2.6 mmol/l) during the Mg(OH)2 period (p less than 0.05) and increased from 6.1 mg/dl (2.0 mmol/l) during the Mg(OH)2 and A1(OH)3 period to 7.0 mg/dl (2.3 mmol/l) during the Al(OH)3 period (p less than 0.05) indicating that Mg(OH)2 could significantly lower SP. However, SP was best controlled (6.1 mg/dl; 2.0 mmol/l) when Al(OH)3 and Mg(OH)2 were used together and all participants preferred the combination therapy to either of the agents alone. These results indicate that Mg(OH)2 is a potentially useful adjunct to A1(OH)3 for managing hyperphosphatemia in patients on maintenance hemodialysis. In this short-term study Mg(OH)3 for managing hyperphosphatemia in patients on maintenance hemodialysis. In this short-term study Mg(OH)2 was well tolerated and with appropriate monitoring did not cause uncontrolled hypermagnesemia. Further studies are clearly required to determine whether long-term therapy with Mg-containing agents is safe in dialysis patients.

Food Preferences Predict Eating Behavior of Very Young Mohawk Children

OBJECTIVE To collect baseline data on energy and nutrient intake and nutrition knowledge, attitudes, and behavior of very young Mohawk children to assist the community in planning an appropriate, targeted nutrition and exercise intervention. DESIGN Energy and nutrient intake data were collected from 24-hour recalls conducted in the childrens homes. Nutrition knowledge, attitudes, and behavior were assessed using a 38-item questionnaire that asked children to report on what foods they like the best, eat most of the time, and think are healthful. The questionnaire was completed in an elementary school on the reservation. Before data collection, we hypothesized that the average diet of the Mohawk children would not meet national dietary recommendations. SUBJECTS One hundred forty-three children, prekindergarten through third grade (aged 4 to 9 years), completed the 24-hour recalls and the questionnaire. An additional 136 children, also prekindergarten through third grade, completed the questionnaire (n = 279). STATISTICS Analysis of variance with a Scheffes multiple-comparison test was used to test for differences among grades and genders for energy and nutrient intake and questionnaire scores. Multiple regression analysis was used to assess the relationship between eating behavior and selected variables. RESULTS A mean daily energy intake of 1,980 kcal consisted of 34% fat, 13% protein, and 52% carbohydrate with 13 g fiber and 235 mg cholesterol. Food preferences were the strongest predictor of behavior, they explained 71% of the variation in the behavior score. APPLICATIONS The major finding of this study, that food preferences are the strongest predictor of reported eating behavior in very young Mohawk children, has implications for behavior change interventions. Focusing on changing what children like to eat, through repeated exposure to new foods in a positive social context, is more likely to change what foods they choose than is simple nutrition education.

Urinary excretion of prostaglandin E2 and prostaglandin F2α in potassium-deficient rats

Potassium-deficiency was induced in rats by dietary deprivation of potassium. The animals became polyuric and urine osmolality decreased more then three-fold compared to controls. Urinary excretion of prostaglandin E2 (PGE2) and prostaglandin F2alpha (PGF2alpha) did not increase during 2 weeks of potassium depletion. Partial inhibition of renal prostaglandin synthesis by meclofenamate did not increase the urine osmolality after water deprivation. These results make unlikely the hypothesis that the polyuria of potassium-deficiency, is the result of enhanced renal synthesis of prostaglandins with subsequent antagonism of the hydro-osmotic effect of vasopressin. Male animals consistently excreted less PGE2 than female animals.

Effect of Dietary Protein Intake on Serum Total CO2 Concentration in Chronic Kidney Disease: Modification of Diet in Renal Disease Study Findings

Metabolic acidosis is a feature of chronic kidney disease (CKD), but whether serum bicarbonate concentration is influenced by variations in dietary protein intake is unknown. For assessing the effect of diet, data that were collected in the Modification of Diet in Renal Disease study were used. In this study, patients with CKD were enrolled into a baseline period, then randomly assigned to follow either a low- or a usual-protein diet (study A, entry GFR 25 to 55 ml/min) or a low- or very low-protein diet, the latter supplemented with ketoanalogs of amino acids (study B, entry GFR 13 to 24 ml/min). Serum [total CO2] and estimated protein intake (EPI) were assessed at entry (n = 1676) and again at 1 yr after randomization, controlling for changes in GFR and other key covariates (n = 723). At entry, serum [total CO2] was inversely related to EPI (1.0 mEq/L lower mean serum [total CO2]/g per kg body wt increase in protein intake/d; P = 0.009). In an intention-to-treat analysis, the reduction in mean EPI in the low-protein group as compared with the usual-protein group (0.41 g/kg body wt per d) was independently associated with a 0.9-mEq/L increase in serum [total CO2], after adjustment for covariates (P < 0.001). No such effect was evident in study B, in which the very low-protein diet group received dietary supplements. Serum [total CO2] is inversely correlated with dietary protein intake in patients with CKD. A reduction in protein intake results in an increase in serum [total CO2].

A native american community initiative to prevent diabetes

The increasing prevalence of obesity and diabetes in the Mohawk Community of Akwesasne led to the formation of an advisory group whos mission was to increase community awareness and strengthen the infrastructure necessary to create a community coalition to promote healthy lifestyles. The methodology used to reach these goals included: obtaining an understanding of the communitys knowledge, attitudes and behaviors about diabetes, diet and exercise using semi-structured interviews and focus groups; analyzing data from a case control study of diabetes and it complications using a medical record review; exploring methods for evaluating energy expenditure in children; and identifying influential community members and organizations. In the last 50 years people had become less physically active and high fat, high caloric foods were more available. Community members were concerned about health and the well-being of their children, had knowledge about healthy lifestyles but lacked confidence and social support for bringing about desired changes. A strong association was documented between diabetes, smoking cigarettes, high blood cholesterol and vascular disease in this community. Approximately 100 persons participated, several hundred received the results in presentations to 17 community organizations, two public fora, letters to participants and articles in local newspapers. Fifty persons and 29 businesses or organizations regarded as strong advocates of healthy lifestyles were identified. From these a community coalition was formed and has initiated programs to reduce dietary fat and increase physical activity in young children.

Impact of methionine on net ketoacid production in humans

An exogenous acid load (NH4Cl) inhibits net ketoacid production in the first week of starvation and the fourth to eighth weeks of ketogenic dieting. To determine whether an acid load produced by amino acid metabolism can similarly modify ketosis, five overweight volunteers ingested methionine (H2SO4), NH4Cl, and NaCl (control), in varying order, each day for seven days during weeks 5 to 8 of hypocaloric ketogenic dieting. During days 5 to 7 of each phase, blood pH, bicarbonate, and pCO2 were stable but lower in the NH4Cl phase (7.32 +/- 0.02, 18.1 +/- 1.2 mmol/L, 35.8 +/- 1.4 mmHg) and the methionine phase (7.33 +/- 0.01, 17.1 +/- 0.9 mmol/L, 34.0 +/- 2.0 mmHg) than in the NaCl phase (7.38 +/- 0.01, 22.3 +/- 0.2 mmol/L, 37.6 +/- 1.6 mmHg), P less than .05. Over this period, blood acetoacetate concentration was lower during the methionine and NH4Cl phases than during NaCl, P less than .05. In addition blood beta-hydroxybutyrate and total ketone-body concentrations were lower in the methionine than NaCl phases, P less than .05. Urinary acetoacetate and beta-hydroxybutyrate excretion fell with both acid loads, P less than .05. Compared with control values, urinary total ketone excretion was suppressed by 67 +/- 10% in the NH4Cl and 89 +/- 3% in the methionine periods. When NaCl was ingested after either of the acid loads, urinary ketone excretion increased by 300% to 700%. Thus, methionine ingestion, which results in an acid challenge equivalent to that of a large protein load, has an impact on net ketoacid production similar to that of NH4Cl.(ABSTRACT TRUNCATED AT 250 WORDS)