Cholesterol-lowering action of plant sterols.

Plant sterols have an extended history of use as cholesterol-lowering agents. Until the 1970s, the principal interest in plant sterols lay in effects of sitosterol, but over the past decade interest has reemerged in using plant sterols in functional foods. Hydrogenated plant sterols have been shown efficacious in lowering lipid levels, inhibiting cholesterol absorption and regressing plaque in animals.

Comparison of deuterium incorporation and mass isotopomer distribution analysis for measurement of human cholesterol biosynthesis.

To compare endogenous cholesterol biosynthesis measured by deuterium incorporation (DI) and mass isotopomer distribution analysis (MIDA), cholesterol fractional and absolute synthetic rates were measured simultaneously by both techniques under identical physiological conditions. Twelve subjects (22 to 39 years of age) underwent a dual stable isotope protocol, involving oral deuterium oxide administration and measurement of incorporation of deuterium into cholesterol coincident with constant infusion of sodium [1-(13)C]acetate and measurement of the mass isotopomer distribution pattern of newly synthesized cholesterol. Synthesis was determined over 24 h with a 7-h feeding period.

Environment and contaminants in traditional food systems of northern indigenous peoples.

Traditional food resources of indigenous peoples are now recognized as containing a variety of environmental contaminants which reach food species through local or long-range transport avenues. In this chapter we review the published reports of contaminants contained in traditional food in northern North America and Europe as organochlorines, heavy metals, and radionuclides. Usually, multiple contaminants are contained in the same food species.

Monitoring glycation of lysozyme by electrospray ionization mass spectrometry.

Electrospray ionization mass spectrometry (ESI-MS) was used to study the glycation of lysozyme by D-glucose (LZM-G) and by D-fructose (LZM-F) under dry heating conditions in the presence and in the absence of oxygen. ESI-MS proved to be a precise method for monitoring protein glycation with respect to following the extent of glycation and changes in the glycoconjugate profile with time. The ESI-MS spectrum of glycated LZM revealed a heterogeneous distribution of glycoforms of LZM at different reaction stages.

Total toxaphene and specific congeners in fish from the Yukon, Canada.

Toxaphene is one of the major persistent organic pollutants with global environmental impacts. We have measured total toxaphene and specific congeners concentrations in 19 fish samples collected from the Yukon, Canada using gas chromatography coupled to ion trap MS/MS. The total toxaphene concentrations ranged from 42 to 242 ng/g (mean = 107+/-61 ng/g).

Comparative performance, blood chemistry, and carcass composition of two lines of Pekin ducks reared mixed or separated by sex.

Male and female Pekin ducks selected (F2 generation) for greater breast muscle thickness (MT) and an unselected control (C) were used in this study under mixed- or separated-sex rearing. Ducks in the separated-sex program had significantly higher body weights than the birds in the mixed-sex program. The ducks selected for greater breast muscle thickness exhibited superior (P < 0.

Immune response of the hibiscus mealybug, Maconellicoccus hirsutus Green (Homoptera: Pseudococcidae), to oviposition of the parasitoid Anagyrus kamali Moursi (Hymenoptera: Encyrtidae).

Anagyrus kamali Moursi has been recently introduced into the Caribbean as a biological agent against the hibiscus mealybug, Maconellicoccus hirsutus Green. This host has a cellular defense reaction that involves encapsulation and melanization of the endoparasitoid egg. The impact of this immune response on the parasitoid progeny was assessed, as well as the response of the parasitoid countermeasures to overcome it.

Four-day multimedia diet records underestimate energy needs in middle-aged and elderly women as determined by doubly-labeled water.

Systematic problems exist in the quantification of food intake in populations using traditional self-reported measures. The objective of this study was to determine the effectiveness of an innovative multimedia diet record (MMDR) for dietary energy intake assessment. Dietary intake was estimated by combining the use of a microcassette tape recorder and 35-mm camera in 53 women whose ages ranged from 50 to 93 y (64.

Temporal modulation of nephrotoxicity, feeding, and drinking in gentamicin-treated rats.

Gentamicin-induced nephrotoxicity varies temporally, with a peak being observed when this antibiotic is administered during the resting period and a trough when given during the activity period of rats. These nychthemeral variations are modified by fasting and by restricted feeding schedules. In this study, food and water intakes of adult female Sprague-Dawley rats were measured during pretreatment (Days 1 to 5) and during treatment (Days 6 to 10) with gentamicin (80 mg/kg/day, i.

A subunit vaccine candidate region of the Entamoeba histolytica galactose-adherence lectin promotes interleukin-12 gene transcription and protein production in human macrophages.

The cysteine-rich region of the 170-kDa subunit galactose-adherence lectin (Gal-lectin) of Entamoeba histolytica is a subunit vaccine candidate and a protective antigen in the gerbil model of amebiasis. Macrophage-mediated immunity is important for protection against E. histolytica and is activated by Th1 cytokines.

Immune response to Giardia duodenalis.

The intestinal protozoan Giardia duodenalis is a widespread opportunistic parasite of humans and animals. This parasite inhabits the upper part of the small intestine and has a direct life cycle. After ingestion of cysts, which are the infective stage, the trophozoites emerge from the cysts in the duodenum and attach to the small intestinal mucosa of the host.

Pressure-induced conformational changes of beta-lactoglobulin by variable-pressure Fourier transform infrared spectroscopy.

Pressure-induced conformational changes in D(2)O solutions of the two genetic variants of beta-lactoglobulin A (beta-lg A) and beta-lactoglobulin B (beta-lg B) and an equal mixture of both variants (beta-lg A+B) were studied by employing variable-pressure Fourier transform infrared (VP-FTIR) spectroscopy. Changes in the secondary structure of beta-lg A were observed at lower pressure compared to beta-lg B, indicating that beta-lg A had a more flexible structure. During the decompression cycle beta-lg A showed protein aggregation, accompanied by an increase in alpha-helical conformation.

Factors Influencing Biological Control of Sphenoclea zeylanica with Alternaria alternata f. sp. sphenocleae.

Alternaria alternata f. sp. sphenocleae is an endemic disease causing a few small necrotic foliar lesions and occasionally a foliar blight on Sphenoclea zeylanica, a problem weed in paddy rice.

Risk factors for iron deficiency anaemia in preschool children in northern Ethiopia.

Objective: To determine risk factors for anaemia in preschool children.

Design: A cross-sectional study.

Setting: Tigray province, northern Ethiopia.

Diet texture modifies outcome of a primary infection with Heligmosomoides polygyrus (nematoda) in mice.

To determine if dietary texture altered the establishment, survival and reproduction of Heligmosomoides polygyrus during a primary infection, commercial mouse chow (Purina Chow) was fed in either pelleted or powdered form to 2 groups of infected BALB/c mice, and a semipurified, biotin-fortified, egg-white-based diet was provided in powdered form to a third group of mice. Diet texture (powdered vs. pelleted) modified parasite establishment, as evidenced by higher worm recovery 6 days postinfection (PI) in both groups of mice fed powdered diets compared with the group fed the pelleted diet, but diet texture had no detectable effect on net or per capita egg production or on day 30 worm survival.

Saponins and phenolic content in plant dietary additives of a traditional subsistence community, the Batemi of Ngorongoro District, Tanzania.

Reports of plants added to milk and meat-based soups by the Maasai and Batemi in East Africa support a role for phenolic antioxidants and hypocholesterolemic agents in the diet, and provide explanation of the low incidence of cardiovascular disease of populations that traditionally consume high levels of dietary fat and cholesterol. Plant food additives used by the Batemi of Ngorongoro District, Tanzania, were tabulated, based on interviews with 22 informants, while 17 specimens were collected in the field and analyzed for saponin and phenolic content. A total of 81% of the Batemi additives and 82% of those known to be used by the Maasai contain potentially hypocholesterolemic saponins and/or phenolics.

Weight loss due to energy restriction suppresses cholesterol biosynthesis in overweight, mildly hypercholesterolemic men.

Mechanisms explaining the decrease in circulatory cholesterol levels after weight loss remain ill defined. The objective was to examine effects of weight loss as achieved through energy restriction upon human in vivo cholesterol biosynthesis. Six subjects (64-77 y, body mass index, 30.

Quantitative analysis and modelling of the behavioural dynamics of Salvelinus fontinalis (brook trout).

Behavioural sequences of juvenile brook trout Salvelinus fontinalis were investigated by time-lapse video-recording in the laboratory. A repertoire of six behavioural states was considered. Time-dependent probabilities of being in a given state, staying in the same state or changing of state, were derived from the behavioural profiles recorded continuously over time for each fish, during 2 h on 2 days.

Inhibition of nitrifiers and methanotrophs from an agricultural humisol by allylsulfide and its implications for environmental studies.

Allylsulfide, an inhibitor of ammonia monooxygenase, was tested to determine its ability to inhibit nitrification and methane oxidation in pure cultures, in agricultural humisol enrichment cultures, and in humisol slurries. We confirmed that allylsulfide is a differential inhibitor of cultures of nitrifiers and methanotrophs at concentrations of 1 and 200 microM, respectively, which result in 50% inhibition. However, although a nitrifying enrichment culture added to sterilized humisol was inhibited 50% by 4 microM allylsulfide, 500 microM allylsulfide was necessary for 50% inhibition of the endogenous nitrifying activity in nonsterile humisol.

Fourier transform infrared spectroscopic investigation of temperature- and pressure-induced disaggregation of amyloid A.

The conformation-sensitive amide I band in the Fourier transform infrared (FTIR) spectra of amyloid A suspensions in D2O was examined as a function of temperature (25-95 degrees C) and applied hydrostatic pressure (1-12 kbar) to assess the stability of the peptide. The principal changes observed upon heating were a significant loss of intermolecular beta-sheet structure, and an increase in the broad band centred at 1644 cm(-1) assigned to unordered structure and alpha-helices of the dissociated species. Application of hydrostatic pressure at ambient temperature resulted in a limited degree of aggregate dissociation.

Gender effects of tall oil versus soybean phytosterols as cholesterol-lowering agents in hamsters.

To examine the effect of gender on the mechanisms of action of phytosterols extracted from tall oil (TO) and soybean (SB) on cholesterol and phytosterol metabolism, male and female hamsters were fed cholesterol-enriched diets containing 0.5 or 1% (w/w) TO or SB phytosterols for 90 days. Plasma lipoprotein cholesterol profile and tissue phytosterol and cholesterol biosynthesis levels were determined.

Intra- and interspecific host discrimination by host-seeking larvae of coleopteran parasitoids.

Intraspecific host discrimination is widespread in solitary parasitoids whose adult females forage for and evaluate host suitability, whereas interspecific discrimination is less common. In some parasitoid species, mostly Diptera and Coleoptera, the larva performs the last step of host searching. It has been suggested that host discrimination will rarely occur in such host-seeking larvae because their low mobility results in a low host encounter rate.

Copulatory behaviour and paternity in the American kestrel: the adaptive significance of frequent copulations.

The adaptive significance of repeated withinpair copulations is not well understood. We analysed the copulatory behaviour of 16 pairs of solitary-nesting American kestrels, Falco sparverius, in southern Quebec (Canada), and the achieved reproductive success (paternity) of 21 kestrel families determined by DNA fingerprinting, in terms of four hypotheses. (1) The paternity assurance hypothesis, which suggests that males copulate frequently to avoid being cuckolded, was rejected because there were few extrapair copulation attempts (<1% of all copulations observed), withinpair copulations were not timed during the fertile period and mate attendance did not increase as the fertile period approached.