John St Peter | University of Minnesota - Twin Cities (original) (raw)

Papers by John St Peter

Current Developments in Nutrition, 2018

Background: Most publications about low-calorie sweeteners (LCSs) focus on person-level intake pr... more Background: Most publications about low-calorie sweeteners (LCSs) focus on person-level intake prevalence. Objective: We assessed LCS distribution in foods, beverages, and food and beverage additions (FBAs), e.g., mayonnaise, in the US adult diet as reported in the NHANES (2007-2012). Methods: Dietary items reported in the first 24-h recall were coded for LCS and/or nutritive sweeteners (NSs) with the use of USDA What We Eat in America food files. We calculated the number of times items were reported and LCS/NS content. Results: Of reported items, 56.1% were foods, 29.1% were beverages, and 14.8% were FBAs. LCS was contained in 0.7% of foods, 8.1% of beverages, and 10.4% of FBAs. This food-level analysis identified FBAs as a significant source of LCSs in the US diet. Conclusion: Identifying the diversity of LCS and NS sources will enhance exposure classification for examining diet and health relations, including body weight management.

Nutrients

Studies of relationships between eating frequency and/or timing and energy intake have not examin... more Studies of relationships between eating frequency and/or timing and energy intake have not examined associations with low-calorie sweeteners (LCS). We assessed the frequency of eating behavior related to LCS consumption emphasizing timing, calorie intake, and body mass index (BMI) among United States (US) adults aged ≥19 years. Using the National Health and Nutrition Examination Survey (NHANES) 2007–2016, we defined eating episodes as food and/or beverage intake within 15 min of one another over the first 24-h dietary recall. We coded items ingested during episodes (n = 136,938) and assessed LCS presence using US Department of Agriculture (USDA) food files. Episode analysis found intakes of foods only (27.4%), beverages only (29.5%), and foods with beverages (43.0%). LCS items were consumed without concurrent calories from other sources in fewer than 2.7% of all episodes. Within participants having normal weight (29.4%), overweight (33.6%) and obese (37.1%) BMIs, LCS consumers (35.2...

Obesity

The use and impact of low-calorie sweeteners (LCS) in relation to the national challenges of over... more The use and impact of low-calorie sweeteners (LCS) in relation to the national challenges of overweight and obesity are complex and controversial. Most research on LCS have focused on the prevalence of consumption of LCS in beverages. The 2015 Dietary Guidelines Advisory Committee emphasized dietary patterns and health rather than a focus on specific nutrients or foods. The committee took this approach to shift the national emphasis onto the context of total rather than individual nutrient consumption. A broader research paradigm is needed to elucidate the actual exposure to LCS and how they are consumed within dietary patterns in the US population. National-level databases exist that can be used to broaden scientific understanding of the effects of LCS and health outcomes. These databases are underutilized, and they provide potential tools for grasping a fuller picture of LCS in the US diet.

Current Developments in Nutrition

Background: Low-calorie sweeteners (LCSs), artificial sweeteners, or high-intensity sweeteners ar... more Background: Low-calorie sweeteners (LCSs), artificial sweeteners, or high-intensity sweeteners are incorporated into foods, beverages, and food and beverage additions (FBAs). Many prior studies have focused on LCS beverage consumption, but not included LCS consumption from foods or FBAs. Objectives: We aimed to describe the prevalence of LCS consumption by US adults, and to examine the relation between intake of products containing LCSs and macronutrients. Methods: Two nonconsecutive 24-h dietary recalls from NHANES 2007-2012 and the National Cancer Institute usual intake method were used to estimate prevalence of LCS intake from foods, beverages, and FBAs, and macronutrients among US adults aged ≥19 y (n = 14,098, weighted n = 218,391,752) in a cross-sectional study. The prevalence of LCS consumption from reported foods, beverages, and FBAs among US adults was examined by sociodemographic characteristics and body mass index (BMI). Logistic regression estimated ORs and 95% CIs for associations between sociodemographic characteristics and LCS use (overall and in foods, beverages, and FBAs). Results: Among adults, 47.8% reported intake of ≥1 food, beverage, or FBA containing LCSs over 2 d. Intake was higher among: women non-Hispanic whites, college graduates or higher, and those with higher income and obese BMIs (P < 0.001). Intake of beverages containing LCSs was higher for ages 51-70 y than 19-30 y and those with overweight and obese BMIs (P < 0.001) than for normal-weight individuals. Calories, carbohydrate, and sugar intake were lower and fiber was higher in LCS-consumers than in nonconsumers. Specifically, calories from beverages were lower in those who reported LCS intake. Conclusions: Individuals reporting LCS consumption demonstrated lower total energy intake than did individuals without LCS intake. Although the main source of LCSs in the US adult diet was beverages (31.9%), we found that FBAs also present a significant contribution (25.2%), surpassing food (9.3%). This enables targeted understanding of national consumption of these products as well as dietary education and intervention opportunities. Curr Dev Nutr 2018;2:nzy054.

The Faseb Journal, Apr 1, 2015

Journal of clinical pharmacology, 2000

Data from three separate single-center studies were combined to assess the pharmacokinetics of or... more Data from three separate single-center studies were combined to assess the pharmacokinetics of orally administered pilocarpine. Pilocarpine concentration-time data were used to generate a data set including 42 subjects (34 males, 8 females) with varying degrees of renal function (average of two estimated creatinine clearance rates of 10 to 112 mL/min). Age ranged from 19 to 88 years. Subjects received single oral doses (range: 2.5-20 mg) of pilocarpine. Plasma samples were collected at time 0; at 20 and 40 minutes; and at 1, 1.5, 2, 3, 4, 6, 8, 12, 16, and 24 hours following dose administration. Cmax and AUC were normalized to a 5 mg exposure in those subjects who received doses other than 5 mg. Plasma pilocarpine concentrations were determined by gas chromatography/mass spectrometry. The pharmacokinetic parameters (elimination rate constant, Cmax, tmax, AUC, Vd/F, and Cl/F) in subjects with impaired renal function were similar to results found in other pharmacokinetic studies invol...

American journal of health-system pharmacy : AJHP : official journal of the American Society of Health-System Pharmacists, Jan 15, 1997

The accuracy of pharmacy technicians versus pharmacists in checking drug doses prepared in syring... more The accuracy of pharmacy technicians versus pharmacists in checking drug doses prepared in syringes for a dialysis program was studied. Three pharmacy technicians from the pharmacy of a regional kidney disease program in Minnesota participated in the study after completing a training program and after common preparation errors had been identified by pharmacists. From November 1995 to April 1996, the technicians used labels printed from a database of pharmacist-verified orders to prepare and label i.v. syringes. Four medications were used-epoetin alfa, calcitriol, heparin prepared from beef lung, and heparin prepared from porcine intestinal mucosa. Each syringe was checked by one of nine pharmacists for accuracy of dose and medication, and all errors were recorded. The technicians checked syringes prepared by other technicians and also recorded errors. Accuracy rates (percentages of syringes correctly evaluated) for pharmacists and technicians were compared. A total of 10,608 syringe...

Clinical pharmacology and therapeutics, 1995

The effects of single and multiple oral doses of zileuton on the pharmacokinetics of antipyrine a... more The effects of single and multiple oral doses of zileuton on the pharmacokinetics of antipyrine and indocyanine green were studied in 16 healthy, nonsmoking adult men by means of a double-blind, randomized, parallel placebo-controlled design. Indocyanine green disposition was not significantly altered by zileuton. Plasma antipyrine clearance declined by 20% (p < 0.0005) and 52% (p < 0.0005) after single and multiple dose zileuton exposure, respectively. Total urinary recovery of unchanged antipyrine and metabolites decreased with zileuton exposure. Selective declines from baseline of 16% (p = 0.007) and 20% (p = 0.003) after single-dose zileuton and 30% (p < 0.0005) and 43% (p < 0.0005) after multiple-dose zileuton were detected in recovery of 4-hydroxyantipyrine and 3-hydroxymethylantipyrine, respectively. Urinary recovery of the N-demethylantipyrine metabolite norantipyrine and percent of conjugation of 3-hydroxymethylantipyrine were unchanged by zileuton. In conclusio...

Pharmaceutical research, 1990

... 36-Hour Urine Collections (Mean % ± SD) 24-hr collection 36-hr collection % of total recovere... more ... 36-Hour Urine Collections (Mean % ± SD) 24-hr collection 36-hr collection % of total recovered Antipyrine alone Antipyrine/ acetaminophen P Antipyrine alone Antipyrine/ acetaminophen P Unchanged AP HMA NORA ОНА 7.4 ... 2. AW Harman, DB Frewin, BG Priestly, and С. В. ...

Pharmaceutical research, 1991

Antipyrine (AP) is a commonly used probe of oxidative metabolism. Indirect evidence demonstrates ... more Antipyrine (AP) is a commonly used probe of oxidative metabolism. Indirect evidence demonstrates formation rate limited disposition of its metabolites. Kinetic studies using antipyrine and its major metabolites 3-hydroxymethylantipyrine (HMA), norantipyrine (NORA), and 4-hydroxyantipyrine (OHA) were completed to investigate the metabolic fate of preformed antipyrine metabolite and to demonstrate directly formation rate-limited metabolite disposition in vivo. Bolus injections of antipyrine and preformed metabolites (40-50 mg/kg) were administered to male, New Zealand white rabbits. Plasma and urine were analyzed using HPLC. These studies demonstrate that HMA, NORA, and OHA are formation rate limited in the rabbit. NORA appears to undergo further extensive oxidative and conjugative metabolism. Unknown additional peaks were detected in urine after NORA dosing but not after HMA or OHA administration. Mass spectroscopy of the unknown HPLC eluents identified potential structures of these ...

PLoS ONE, 2014

Background: HIV infection occurs in 30% of children with severe acute malnutrition in sub-Saharan... more Background: HIV infection occurs in 30% of children with severe acute malnutrition in sub-Saharan Africa. Effects of HIV on the pathophysiology and recovery from malnutrition are poorly understood.

Urological Research, 2007

Crystal adherence in the urinary tract has been studied using the chemically injured rat bladder ... more Crystal adherence in the urinary tract has been studied using the chemically injured rat bladder and cell cultures. These studies have provided evidence that mucin prevents adherence and have studied various compounds for their ability to promote or inhibit crystal adherence. Little work has been done examining the eVect on crystal adherence of traditional risk factors for stone disease. The study reported here examined the eVect hypercalciuria, hyperoxaluria and pH on calcium oxalate crystal adherence using the intact rat bladder model. Calcium at levels seen in hypercalciuric stone formers was associated with increased adherence. Oxalate at levels seen in stone formers had no eVect on adherence. There was a tendency to increased crystal adherence at higher pH values only when phosphorus was present as the buVer. Hypercalciuria is a risk factor for stone disease by increasing the level of saturation of calcium oxalate and calcium phosphate in the urine and by decreasing inhibitor function. This study suggests that it may also play a role by increasing crystal adherence within the urinary tract.

Translational Research, 2011

Vitamin D has in vitro and in vivo effects on β-cells and insulin sensitivity. Vitamin D deficien... more Vitamin D has in vitro and in vivo effects on β-cells and insulin sensitivity. Vitamin D deficiency (VDD) has been associated with onset and progression of type 2 diabetes mellitus (DM-2). However, studies involving supplementation of vitamin D in subjects with previously established diabetes have demonstrated inconsistent effects on insulin sensitivity. The aim of this open-label study was to assess the effects of high dose vitamin D3 supplementation on insulin sensitivity in subjects with VDD and impaired fasting glucose. We studied 8 subjects with VDD and prediabetes with the modified frequently sampled intravenous glucose tolerance (mFSIGT) test before and after vitamin D supplementation. Vitamin D3 was administered as 10,000 IU daily for 4 weeks. The mFSIGT was analyzed with MinMod Millennnium to obtain estimates of Acute Insulin Response to Glucose (AIRg), Insulin Sensitivity (SI), and Disposition Index (DI). We found that AIRg decreased (p = 0.011) and insulin sensitivity, expressed as SI, increased (p = 0.012) after a intervention with vitamin D. If these findings are repeated in a randomized, doubleblind, sudy the results indicate that orally administered high dose vitamin D3 supplementation improves insulin sensitivity in subjects with impaired fasting glucose and suggests that high dose vitamin D3 supplementation might provide an inexpensive public health measure in preventing, or at least delaying, the progression from impaired fasting glucose to diabetes.

Pharmacotherapy, 2000

Objective. To evaluate and compare the relationship between dosage and coagulation parameters, as... more Objective. To evaluate and compare the relationship between dosage and coagulation parameters, as well as safety profiles, of ascending bolus and infusion dosages of argatroban versus heparin in three phase I studies. Design. Two randomized, double-blind studies compared argatroban and heparin, and one open-label, dose-escalation study further evaluated argatroban. Setting. University teaching hospital clinical research unit. Patients. Healthy men (aged 22-62 yrs).

Pharmacotherapy, 2001

To characterize frequency of liver enzyme elevation in patients with type 2 diabetes mellitus rec... more To characterize frequency of liver enzyme elevation in patients with type 2 diabetes mellitus receiving troglitazone. Retrospective study. Hospital-affiliated medical center. Two hundred ninety-one patients with type 2 diabetes mellitus. Data from patients with an average troglitazone exposure of 412.7 +/- 255.6 days were studied. Enzyme elevations more than 1.5 times the upper limit of normal (ULN) occurred in 17 patients (5.8%) and more than 3-fold elevations in 6 (2.1%). The relationship among enzyme elevation events, demographic factors, duration of troglitazone exposure, frequency of monitoring, and concurrent drugs (limited to glucose and lipid-lowering agents) was assessed by multiple logistic regression. Age was an independent predictor of risk (p=0.009), and concurrent insulin therapy approached statistical significance (p=0.051) for 1.5-fold ULN elevation in liver enzymes. Age and concurrent therapy with 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors were the only significant predictors of 3-fold ULN elevations (p=0.03 and p=0.04, respectively). Several factors appear to increase the risk of enzyme elevation events in patients treated with troglitazone.

Obesity, 2000

VESSEY. Diabetes disease stage predicts weight loss outcomes with long-term appetite suppressants... more VESSEY. Diabetes disease stage predicts weight loss outcomes with long-term appetite suppressants. Obes Res. 2000:8:43-48. Objectives: Characterize degree of weight loss with stage of diabetes and describe its effect on cardiovascular disease risk factors in obese patients with and without diabetes. Research Methods and Procedures: Retrospective cohort analysis from patients participating in a long-term weight management protocol using diet, exercise, behavioral modification, and appetite-suppressant therapy. Patient groups, with (n ϭ 19) and without diabetes (n ϭ 19) were matched for age, gender, and weight before weight loss therapy. The effect of 12 months of therapy on weight, blood pressure, glycemic control, lipid profile, and medication requirements were tested. Additionally, patients were grouped or staged based upon therapy required for control of diabetes at the beginning of weight loss intervention. Analysis of covariance described relationships between diabetes disease stage and weight loss at 12 months. Results: Nondiabetic patients had greater mean reduction in BMI than the diabetic group (7.98 kg/m 2 vs. 4.77 kg/m 2 , p Ͻ 0.01). A significant linear trend (p Ͻ 0.001) for decreasing weight loss with stage of diabetes was observed. Blood pressure, lipid profile, and glycemia improved significantly. The average daily glyburide-equivalent dose decreased from 9.4 to 3.0 mg (p Ͻ 0.01). Discussion: Patients with diabetes lost less weight than similarly obese patients without diabetes. Regardless of differential weight loss between groups, cardiovascular disease risk factors improved. Hypoglycemic medication requirements decreased with weight loss therapy. A predictive relationship may exist between diabetes disease stage before weight loss therapy and future weight loss potential.

Nicotine & Tobacco Research, 1999

Active immunization of rats against nicotine reduces the distribution of a single intravenous dos... more Active immunization of rats against nicotine reduces the distribution of a single intravenous dose of nicotine to brain. The current study examined the effects of immunization on the distribution of repeated doses of nicotine, and on estimates of nicotine pharmacokinetic parameters. Groups of rats received five repeated doses of nicotine over 80 min (total dose equivalent to the nicotine intake from one, three or 10 cigarettes in a human). The serum nicotine concentration in immunized rats was 160-430% higher than controls after the fifth dose, demonstrating binding of nicotine to antibody. Brain nicotine concentration in immunized rats was reduced by 30-46%. The reduction in distribution of nicotine to brain correlated with the serum hapten-specific antibody concentration, the percentage of nicotine bound in serum, and with the unbound nicotine concentration in serum. In immunized rats, nicotine had a smaller steady state volume of distribution, lower systemic clearance, and longer terminal half-life than in controls. These data demonstrate that immunization against nicotine reduces nicotine distribution to brain, even after multiple nicotine doses at rates approximating heavy cigarette smoking. Whether this reduction in nicotine distribution is large enough to alter nicotine's physiological or behavioral effects remains to be studied.

New England Journal of Medicine, 1998

After case reports of cardiac-valve abnormalities related to the use of appetite suppressants wer... more After case reports of cardiac-valve abnormalities related to the use of appetite suppressants were published, we undertook a study to determine the prevalence of the problem using transthoracic echocardiography. We examined patients who had taken dexfenfluramine alone, dexfenfluramine and phentermine, or fenfluramine and phentermine for various periods. We enrolled obese patients who had taken or were taking these agents during open-label trials from January 1994 through August 1997. We also recruited subjects who had not taken appetite suppressants and who were matched to the patients for sex, height, and pretreatment age and body-mass index. The presence of cardiac-valve abnormalities, defined by the Food and Drug Administration and Centers for Disease Control and Prevention as at least mild aortic-valve or moderate mitral-valve insufficiency, was determined independently by at least two cardiologists. Multivariate logistic-regression analysis was used to identify factors associated with cardiac-valve abnormalities. Echocardiograms were available for 257 patients and 239 control subjects. The association between the use of any appetite suppressant and cardiac-valve abnormalities was analyzed in a final matched group of 233 pairs of patients and controls. A total of 1.3 percent of the controls (3 of 233) and 22.7 percent of the patients (53 of 233) met the case definition for cardiac-valve abnormalities (odds ratio, 22.6; 95 percent confidence interval, 7.1 to 114.2; P<0.001). The odds ratio for such cardiac-valve abnormalities was 12.7 (95 percent confidence interval, 2.9 to 56.4) with the use of dexfenfluramine alone, 24.5 (5.9 to 102.2) with the use of dexfenfluramine and phentermine, and 26.3 (7.9 to 87.1) with the use of fenfluramine and phentermine. Obese patients who took fenfluramine and phentermine, dexfenfluramine alone, or dexfenfluramine and phentermine had a significantly higher prevalence of cardiac valvular insufficiency than a matched group of control subjects.

Journal of Pharmaceutical Sciences, 1996

0 The primary purpose of this study was to assess the influence of doxylamine and phenobarbital o... more 0 The primary purpose of this study was to assess the influence of doxylamine and phenobarbital on antipyrine/metabolites pharmacokinetics and 6 -hydroxycortisol urinary excretion. This study was conducted in 48 healthy male human volunteers (16 per treatment group) using a parallel study design. Treatment groups consisted of 12.5 mg of doxylamine succinate, placebo, or 30 mg of phenobarbital administered orally every 6 h for 17 days. Results indicate that no statistically significant differences were observed between the doxylamine and placebo groups that are indicative of enzyme induction. For the phenobarbital group, a significant increase for antipyrine total (36 versus 45 mL/h/kg) and nonrenal (35 versus 44 mL/h/kg) clearances and 6 -hydroxycortisol excretion (338 versus 529 µg) and a significant decrease in the terminal exponential half-life (11 versus 9 h) of antipyrine were observed.