Volanesorsen for treatment of patients with familial chylomicronemia syndrome.

Familial chylomicronemia syndrome (FCS) is a rare autosomal recessive disorder typically caused by mutations in genes for lipoprotein lipase (LPL), apolipoprotein C-II (Apo-CII), apolipoprotein A-V (Apo-AV), lipase maturation factor 1 (LMF1) and glycosylphosphatidylinositol-anchored high-density lipoprotein-binding protein 1 (GPI-HBP1). FCS is associated with severe morbidity that includes recurrent pancreatitis and other problems. Effective treatment to reliably prevent complications has been unavailable, so there is a quest to identify novel interventions to achieve sustained triglyceride lowering and prevention of pancreatitis. Apolipoprotein C-III (Apo-CIII) interferes with triglyceride clearance by blocking LPL and alternative pathways. Volanesorsen is an experimental antisense oligonucleotide that inhibits translation of Apo-CIII mRNA, thereby substantially lowering plasma levels of Apo-CIII and triglycerides. It is being developed for treatment of patients with FCS and refractory hypertriglyceridemia. Data from a variety of clinical trials have been very encouraging, with documentation of excellent triglyceride-lowering efficacy, but there have been concerns about the risk of drug-related thrombocytopenia and bleeding that contributed to the recent decision by the Food and Drug Administration (FDA) to not approve the drug for clinical use. Clinical trials testing the safety and efficacy of volanesorsen are ongoing, so there is hope that the drug ultimately will be approved and available for treatment of high-risk patients with FCS.

Healthy Eating Index and obesity.

BACKGROUND: There is a continuing need to examine the relationship between diet quality and health in the population. The Healthy Eating Index (HEI) has been developed as a composite measure of diet quality by the US Department of Agriculture. OBJECTIVES: The first objective was to use the HEI to assess the diet quality of a representative sample of the US population and population groups. The second objective was to examine the association between HEI and obesity. DESIGN: Cross-sectional analysis of data from 10 930 adults who participated in the Third National Health and Nutrition Examination Survey. Sociodemographic, physical activity, dietary, and health data were used in the analysis. Diet quality was assessed with the HEI score, ranging from 0 to 100, based on 10 dietary criteria. A low HEI score indicates poor diet. RESULTS: A majority of survey participants had a low HEI score. The percentage of individuals classified as having a poor diet varied by age, gender, race/ethnicity, income, and education. A low HEI score was associated with overweight and obesity. There was a graded increase in the odds ratio of obesity across the HEI category after adjusting for age, gender, race/ethnicity, physical activity, smoking, alcohol use, income, and education. CONCLUSIONS: An index of diet quality, such as HEI, may provide a comprehensive assessment of diet in the population. Since the HEI is based on the US Dietary Guidelines, the use of these guidelines as a way to improve health should be emphasized. However, the overall effectiveness of these guidelines in disease prevention needs to be studied further.

Catechins are bioavailable in men and women drinking black tea throughout the day.

Tea consumption has been associated with reduced risk of both cancer and cardiovascular disease in population studies, but clinical data demonstrating bioavailability of the individual catechins and other polyphenolic components of tea are limited. This study assessed the apparent bioavailability of the prominent catechins from black tea in humans drinking tea throughout the day. After 5 d of consuming a low flavonoid diet, subjects drank a black tea preparation containing 15.48, 36.54, 16.74, and 31.14 mg of (-)-epigallocatechin (EGC), (-)-epicatechin (EC), (-)-epigallocatechin gallate (EGCG) and (-)-epicatechin gallate (ECG), respectively, at four time points (0, 2, 4 and 6 h). Blood, urine and fecal specimens were collected over a 24- to 72-h period and catechins were quantified by HPLC with coularray detection. Plasma concentrations of EGC, EC and EGCG increased significantly relative to baseline (P < 0.05). Plasma EGC, EC and EGCG peaked after 5 h, whereas ECG peaked at 24 h. Urinary excretion of EGC and EC, which peaked at 5 h, was increased relative to baseline amounts (P < 0.05) and fecal excretion of all four catechins was increased relative to baseline (P < 0.05). Approximately 1.68% of ingested catechins were present in the plasma, urine and feces, and the apparent bioavailability of the gallated catechins was lower than the nongallated forms. Thus, catechins were bioavailable. However, unless they are rapidly metabolized or sequestered, the catechins appeared to be absorbed in amounts that were small relative to intake.

Analysis of tea polyphenols.

Tea is the most highly consumed beverage in the world, other than water. However, unlike water, tea contains substantial amounts of polyphenols that have unique biological activities and may be responsible for many of the health benefits of tea. As a result, it is essential to be able to measure the various tea-associated polyphenols. Total polyphenol content is currently measured by using methodology based on reducing activity. Several HPLC systems with detectors that, collectively, have wide ranges in sensitivity have been developed for analysis of individual flavonoids in tea and biological samples, and for theaflavins in tea. Catechins also have been measured in plasma by solid phase extraction, addition of a chromophore, and colorimetric quantification. Except for theaflavins in tea, routine and robust methods for the measurement of polyphenol condensation products (dimers and thearubigens) in tea and biological samples have not been developed. Although in vitro and animal studies suggest substantial metabolism of flavonoids in the gastrointestinal tract, only a single HPLC procedure has been assembled for monitoring the metabolic products of quercetin in urine of human subjects.

The effect of a low carotenoid diet on malondialdehyde-thiobarbituric acid (MDA-TBA) concentrations in women: a placebo-controlled double-blind study.

OBJECTIVE: The purpose of the study was to evaluate the effect of a low carotenoid diet (83 micrograms Beta-carotene) on malondialdehyde-thiobarbituric acid (MDA-TBA) concentrations of nine pre-menopausal women. METHODS: Subjects lived on the metabolic research unit of the Western Human Nutrition Research Center (WHNRC), where diet, exercise and other activities were controlled. Five subjects (Group C, control group) consumed a low carotenoid diet and received an additional 0.5 mg/day of Beta-carotene while four subjects (Group P, placebo group) received only the low carotenoid diet during days 1 to 60 (period 1). All subjects received 0.5 mg/day of Beta-carotene during days 60 to 100 (period 2), plus three capsules/day mixed carotenoid supplement (Neo-Life Company) during study days 100 to 120. Changes in MDA-TBA concentrations were analyzed during the study periods and between the groups. RESULTS: At the start of the study (day 1), no significant difference in the MDA-TBA concentration was observed between the control (Group C) and the placebo (Group P) subjects. During period 1 (days 2 to 60), when Group P subjects consumed the low carotenoid diet without supplementation, the MDA-TBA values for Group P rose markedly and were significantly (p < 0.05) higher than the MDA-TBA values for Group C subjects who were receiving carotenoid supplementation. During period 2 (days 60 to 100) when both groups received carotenoid supplementation, the MDA-TBA values of Group P subjects were significantly (p < 0.05) reduced to the point where they were similar to the MDA-TBA values for Group C subjects. CONCLUSIONS: These findings provide evidence to support the beneficial effects of carotenoids in preventing lipid peroxidation in the cells. Further studies are needed to identify the exact mechanism by which carotenoids prevent lipid peroxidation and the amount needed for normal activity.

Simulated ABO and Rh blood typing.

BACKGROUND: Blood typing historically has been used to introduce students to the concepts of immunohematology. Risk of disease transmission has compelled school districts to prohibit the use of human blood in student laboratories. A method is needed that will safely simulate ABO and Rh typing. STUDY DESIGN AND METHODS: A method that uses inorganic salt solutions to simulate ABO and Rh antigens and antibodies was studied. Additional salt solutions and diluents were tested to investigate the feasibility of simulating both ABO and Rh typing in a more realistic medium. RESULTS: Cobalt nitrate and sodium hydroxide were found to successfully simulate D and anti-D, respectively. The addition of these solutions did not produce cross-reactions in ABO tests. Use of simulated blood as a diluent improved the appearance of the samples. CONCLUSION: This method can safely and inexpensively simulate ABO and Rh blood typing procedures and provide students with hands-on blood-typing experience.

Chromatographic enzyme immunoassay for T-2 toxin.

Both the active ester and maleimide moieties of the cross-linking reagent, N-[(gamma-maleimidobutyryl)oxy]succinimide (GMBS), were found to react with the primary amino groups on ribonuclease (RNase). This largely inactivated RNase towards a polymeric (but not monomeric) substrate. Citraconylating the RNase first, so that essentially only a single primary amino group remained to react with GMBS, overcame this problem. The subsequent maleimido-citraconyl-RNase was used to prepare a 1:1.1 M conjugate of anti-T-2 toxin Fab' and RNase (Fab'-RNase) in a 76% yield. The conjugate was used to detect as little as 0.1 microgram of T-2 toxin based on the ability of T-2 toxin to specifically displace Fab'-RNase complexed to a T-2 agarose affinity gel.

Repetitive hit-and-run fluoroimmunoassay for T-2 toxin.

A monoclonal antibody for T-2 toxin is converted to a Fab'-fluorescein derivative. The latter is specifically complexed onto a T-2 agarose gel. Fifteen successive doses of T-2 ranging from 1 to 50 ng are then repetitively and linearly detected using a column packed with a small volume (0.2 ml) of this gel without recharging with Fab'-fluorescein. For these assays the effluent from the column is monitored with a spectrofluorometer.

Tresyl activation of a hydroxyalkyl ligand for coupling to a hydrazide gel: stable immobilization of T-2 toxin for affinity purification of T-2 antibody.

A stable T-2 hydrazide gel is prepared by activating T-2 toxin with tresyl chloride followed by coupling to agarose-adipic acid hydrazide. Utilized as an affinity chromatography column, this T-2 hydrazide gel purifies a monoclonal antibody for T-2 in high yield directly from ascites fluid. Specific antibody trapped on the column is eluted either with excess T-2 or at pH 11.6. Much less successful are two other T-2 affinity columns that were prepared and evaluated: T-2 bovine serum albumin Affi-Gel 15 and T-2 hexylamine Sepharose.

Soluble antibody affinity chromatography technique investigated with ultratrace [125I]thyroxine.

An amount of 10 pg of [125I]thyroxine was subjected to DEAE agarose chromatography and then complexed with an antibody. Recycling of the [125I]thyroxine now as a complex with the antibody through a second DEAE agarose column under the same conditions gave a change in the retention of the [125I]thyroxine that potentially constitutes a specific shift away from co-eluting interferences from the first column. The [125I]thyroxine was then dissociated from the antibody and subjected to a third DEAE agarose column for additional shifting of its chromatographic retention. Since the overall recovery of the [125I]thyroxine is 36%, this soluble antibody affinity technique potentially is useful for sample clean-up in labeling analysis of ultratrace solutes such as thyroxine.