Brent J. Shriver

Effects of conventional and grass feeding systems on the nutrient composition of beef

The objectives of this study were to determine the nutrient composition of grass-fed beef in the United States for inclusion in the USDA National Nutrient Database for Standard Reference, and to compare the fatty acid composition of grass-fed and conventionally fed (control) beef. Ground beef (GB) and strip steaks (SS) were collected on 3 separate occasions from 15 grass-fed beef producers that represented 13 different states, whereas control beef samples were collected from 3 regions (Ohio, South Dakota, and Texas) of the United States on 3 separate occasions. Concentrations of minerals, choline, vitamin B(12), and thiamine were determined for grass-fed beef samples. Grass-fed GB samples had less Mg, P, and K (P < 0.05), and more Na, Zn, and vitamin B(12) (P < 0.05) than SS samples. Fat color, marbling, and pH were assessed for grass-fed and control SS. Subjective evaluation of the SS indicated that grass-fed beef had fat that was more yellow in color than control beef. Percentages of total fat, total cholesterol, and fatty acids along with trans fatty acids and CLA were determined for grass-fed and control SS and GB. Grass-fed SS had less total fat than control SS (P = 0.001), but both grass-fed and control SS were considered lean, because their total fat content was 4.3% or less. For both GB and SS, grass-fed beef had significantly less (P = 0.001 and P = 0.023, respectively) content of MUFA and a greater content of SFA, n-3 fatty acids, CLA, and trans-vaccenic acid than did the control samples. Concentrations of PUFA, trans fatty acids, n-6 fatty acids, and cholesterol did not differ between grass-fed and control ground beef. Trans-vaccenic acid (trans-11 18:1) made up the greatest concentration of the total trans fats in grass-fed beef, whereas CLA accounted for approximately 15% of the total trans fats. Although the fatty acid composition of grass-fed and conventionally fed beef was different, conclusions on the possible effects of these differences on human health cannot be made without further investigation.

Dimethyldiselenide and Methylseleninic Acid Generate Superoxide in an In Vitro Chemiluminescence Assay in the Presence of Glutathione: Implications for the Anticarcinogenic Activity of L-Selenomethionine and L-Se-Methylselenocysteine

The reduction of cancer incidence by dietary supplementation with L-selenomethionine, L-Se-methylselenocysteine, and other methylated selenium compounds and metabolites is believed to be due to the metabolic generation of the monomethylated selenium species methylselenol. Dimethyldiselenide and methylseleninic acid were reduced by glutathione in an in vitro chemiluminescent assay in the presence of lucigenin for the detection of superoxide (O2 - ). The methylselenol produced on reduction of dimethyldiselenide and methylseleninic acid was found to be highly catalytic, continuously generating a steady state of O2 - . The O2 - detected by the chemiluminescence generated by methylselenol was fully quenched by superoxide dismutase, causing a complete cessation of chemiluminescence. In contrast, dimethyldisulfide in the presence of glutathione was not catalytic to any measurable extent and did not generate any superoxide. These in vitro results suggest that methylselenol catalysis is possible in vivo, and if metabolism generates sufficient concentrations of methlylselenol from L-selenomethionine or L-Se-methylselenocysteine in vivo, it could change the redox status of cells and oxidatively induce cellular apoptosis.

Evidence Review of Technology and Dietary Assessment

SIGNIFICANCE Diets high in fruit and vegetable consumption are associated with a decrease in chronic diseases. Dietary factors are linked to 4 of the 10 leading noncommunicable causes of death: cardiovascular disease, some cancers, stroke, and type 2 diabetes. Accurately measuring dietary patterns has many challenges. Dietary intake measurement has traditionally relied on self-report instruments such as 24-hour recall, food record, and food frequency questionnaires to record consumption history. These methods have inherent limitations in detecting small but important changes in fruit and vegetable consumption patterns. Promising advances in technology have made more sophisticated techniques for recording dietary intake possible. Computers and Web-based programs, handheld personal digital assistants with cameras and telephone cards, smart phones, cameras, and video recorders options may reduce the burden of recording what has been consumed. Furthermore, technology-based methods of dietary assessment may provide a higher degree of reliability and validity in visually determining fruit and vegetable consumption, and additional study is warranted. PURPOSE The purpose of this article is to present a review of the evidence on the effectiveness of technology-based methods for dietary assessment, which included fruit and vegetable consumption. APPROACH One hundred and eighty-seven articles published between 1998 and 2008 were initially identified. Fifteen met the study inclusion criteria and were evaluated by an interdisciplinary team using the Stetler Strength of Evidence Scale. RESULTS Six technology-based methods for dietary assessment were identified. Findings from validity and reliability testing of technology-based methods are encouraging and need replication. Clinically important features offered through technology may reduce reporting burden and offer behavioral feedback to users. Methodologically sound, empirical research into using technology-based application for dietary assessment in a variety of populations of sufficient size is needed.

Pilot Using World Wide Web to Prevent Diabetes in Adolescents

This pilot study tested the effects of an interactive nutrition education Web site on fruit, vegetable, and fat consumption in minority adolescents genetically at risk for Type 2 diabetes. A one-group nonexperimental pretest, posttest focus group design was used. Twenty-one sixth-grade to eighth-grade junior high adolescents who were minorities volunteered to participate. Participants received 5 hours of Web-based nutrition education over 3 weeks. A significant difference in fat consumption was supported from the computerized dietary assessment. No difference was found in fruit or vegetable consumption. Comparative data indicated a rise in body mass index (BMI) percentile from 88.03 (1999) to 88.40 (2002; boys) and 88.25 (1999) to 91.2 (2002; girls). Focus group responses supported the satisfaction of adolescents in the study with the use of the Web-based intervention for nutrition education. Healthy eating interventions using Web-based nutrition education should be further investigated with adolescents.

The effects of dietary selenomethionine on polyamines and azoxymethane-induced aberrant crypts

We evaluated the effects of dietary selenomethionine supplementation on colonic polyamine levels and the ability of L-selenomethionine supplementation to modulate the carcinogenic activity of azoxymethane (AOM) in the rat colon. Four-week-old male F344 rats were treated with 15 mg/kg body weight of AOM once a week for 2 weeks. Dietary selenomethionine at a concentration of either 1 or 2 ppm was administered in AIN-76A rodent diet to AOM-treated animals for 16 weeks. Aberrant crypt foci (ACF), precursor lesions of colon cancer, were investigated after the 16 week treatment course. Selenomethionine given in the diet at 2 ppm markedly reduced the number of aberrant crypt foci. The multiplicity of ACFs (i.e. the number of aberrant crypts/focus) and the percentage of microadenomas were also affected by selenomethionine in a dose dependent manner. However, evaluation of the colonic tissue polyamine levels between control and treated groups showed no significant difference. These results demonstrate that selenomethionine can modulate the development of AOM-induced premalignant lesions through a polyamine-independent mechanism.

Technology-based methods of dietary assessment: recent developments and considerations for clinical practice.

Purpose of reviewThe objective of this review is to provide an overview of recent findings in technology-based methods for the collection and analysis of dietary information, and explore the potential implications of these technologies for dietary assessment in a clinical setting. Recent findingsNumerous technology-based methods for dietary assessment have emerged in recent years. These methodologies have the potential to enhance the dietary assessment process, and overall appear to yield valid results in a wide variety of populations. However, as is the case with the existing technologies they are designed to replace, none is error free and each has its own unique limitations. Therefore, the decision to incorporate one of these methodologies into clinical practice should only be made after a thorough evaluation of the methodology and with specific outcome goals in mind. SummaryEvidence supporting the emerging role of technology-based methods for dietary assessment is growing. As technological advances move rapidly forward it is important to consider a theoretical foundation to help guide the translation of these innovations into routine use in clinical practice.

Identification of intermediate filament keratin proteins in parakeratinized odontogenic keratocysts. A preliminary study

The keratin proteins were extracted from the epithelial lining of three odontogenic keratocyst specimens. Two of the specimens were from a patient with nevoid basal cell carcinoma syndrome; the third was a solitary lesion. Seven keratin proteins with molecular weights of 46, 48, 50, 52, 54, 58, and 59 kilodaltons were identified by SDS-polyacrylamide gel electrophoresis and immunoblotting with antikeratin antiserum. The reproducibility of the pattern of molecular markers implies a series of genetic events coincident with the characteristic pattern of epithelial differentiation.

Effectiveness of cell phones and mypyramidtracker.gov to estimate fruit and vegetable intake

AIM AND BACKGROUND Inadequate fruit and vegetable intake is linked to leading causes of global mortality and rise in obesity. Measuring fruit and vegetable intake is problematic. Advances in cell phone technologies may improve the accuracy and ease of recording diet. This study tested the effectiveness of using cell phones with digital pictures to prompt memory and mypyramidtracker.gov to estimate self-reported fruit and vegetable intake in 69 college students. METHODS A repeated measures design was used. Focus groups provided feedback on the acceptability, usability, and feasibility of cell phones for diet recording in this population. RESULTS A statistically significant difference in fruit and vegetable scores, F(1, 58)=4.64, p=.04, was supported between cell phone use for short-term memory prompt and mypyramidtracker.gov alone. CONCLUSIONS Cell phone pictures improved memory and accuracy of recall when using an online self-reported interactive diet record and was considered an easy, relevant, and accessible way to record diet.

Non‐hydrogenated cottonseed oil as a deep‐fat frying medium

Purpose – The purpose of this study is to compare the oxidative stability of non‐hydrogenated cottonseed oil with that of the partially hydrogenated oils commonly used as a deep‐fat frying medium by the restaurant industry when used to prepare French fries in order to reduce trans‐fatty acids.Design/methodology/approach – Stability characteristics of non‐hydrogenated cottonseed oil and two hydrogenated oils, canola and soybean, were evaluated in deep‐fat frying applications. French fries were analyzed for total polar compounds, and the oils were analyzed for iodine, peroxide, p‐anisidine and totox values, and free fatty acids.Findings – Canola and soybean oil had significantly lower iodine values than cottonseed oil. Free fatty acid values were not significantly different among the oils (0.256 per cent oleic acid). Initially cottonseed oil had higher peroxide, p‐anisidine, and totox values compared with canola and soybean oil. However, as days of frying increased, values trended closer together. Total pol...