bluuebunny/crossref_metadata_2025 huggingface dataset:
Molecular biological methods for studying the gut microbiota: the EU human gut flora project
Authors: Blaut M. , Collins M.D. , Welling G. W. , Doré J. , van Loo J. , de Vos W.
Published: July 2006

Seven European laboratories co-operated in a joint project (FAIR CT97-3035) to develop, refine and apply molecular methods towards facilitating elucidation of the complex composition of the human intestinal microflora and to devise robust methodologies for monitoring the gut flora in response to diet. An extensive database of 16S rRNA sequences for tracking intestinal bacteria was generated by sequencing the 16S rRNA genes of new faecal isolates and of clones obtained by amplification with polymerase chain reaction (PCR) on faecal DNA from subjects belonging to different age groups. The analyses indicated that the number of different species (diversity) present in the human gut increased with age. The sequence information generated, provided the basis for design of 16S rRNA-directed oligonucleotide probes to specifically detect bacteria at various levels of phylogenetic hierarchy. The probes were tested for their specificity and used in whole-cell and dot-blot hybridisations. The applicability of the developed methods was demonstrated in several studies and the major outcomes are described.
Non–digestible oligosaccharides and defense functions: lessons learned from animal models
Authors: Buddington R. K. , Kelly-Quagliana K. , Buddington K. K. , Kimura Y.
Published: July 2006

Animals are constantly exposed to a diversity of health challenges and the gastrointestinal tract (GIT) is a major, if not the principal, site of exposure. Animal models and a limited number of human clinical studies have shown that the assemblages and metabolic activities of the resident bacteria are important determinants of the effectiveness of the various host defense mechanisms and thereby influence the ability of animals to respond to health challenges. The assemblages of bacteria resident in the GIT provide a first line of defense that can exclude invading pathogens, reduce the proliferation of opportunistic pathogens already resident in the GIT, and reduce the availability, carcinogenicity, or toxicity of noxious chemicals. The mucosa of the GIT is a second, multilayered line of defense that includes the mucous and other secretions, the epithelial cells, and immune-associated cells scattered within and under the epithelium. The final line of defense contends with pathogens or noxious chemicals that transcend the mucosal barrier and enter the host and consists of the innate and acquired components of the systemic immune system and the xenobiotic metabolizing enzymes. The lactic acid producing bacteria (LAB) are considered to be immunomodulatory and directly or indirectly influence the GIT and systemic defense functions. Corresponding with this, supplementing the diet with inulin, oligofructose, or other nondigestible oligosaccharides that increase the densities and metabolic capacities of the LAB enhances defense mechanisms of the host, increases resistance to various health challenges, and accelerates recovery of the GIT after disturbances.
Human studies with probiotics and prebiotics: clinical implications
Authors: Saavedra J. M. , Tschernia A.
Published: July 2006

Probiotic agents have been shown to have significant clinical beneficial effects in the prevention and management of gastrointestinal and non-gastrointestinal conditions. These observations have led to work demonstrating that an important mechanism of these agents is their close interaction with the gut associated lymphoid tissue (GALT) and suggested immunomodulatory effects on systemic immune response. Studies on the possibility thatprebiotic agents might directly or indirectly induce similar immunomodulation have only recently begun. The preliminary findings of several recent human clinical trials reviewed in this article indicate that prebiotics may indeed prove to be a clinically beneficial dietary supplement, in the context of novel nutritional strategies for the management of gastrointestinal and systemic conditions.
Inulin and oligofructose: effects on lipid metabolism from human studies
Authors: Williams C. M. , Jackson K. G.
Published: July 2006

Although convincing lipid-lowering effects of the fructo-oligosaccharide, inulin, have been demonstrated in animals, attempts to reproduce similar effects in man have produced conflicting findings. This may be because of the much lower doses which can be used due to the adverse gastrointestinal symptoms exhibited by most subjects consuming in excess of 15 g/d. There are nine studies reported in the literature which have investigated the response of blood lipids (usually total and LDL-cholesterol and triacylglycerol) to inulin or oligofructose supplementation in human volunteers. Three have observed no effects of inulin or oligofructose on blood levels of cholesterol or triacylglycerol, three have shown significant reductions in triacylglycerol, whilst four have shown modest reductions in total and LDL-cholesterol. Studies have been conducted in both normo- and moderately hyperlipidaemic subjects. Differences in study outcomes do not appear to be due to differences in the type or dose of oligosaccharides used nor the duration of the studies. Because animal studies have identified inhibition of hepatic fatty acid synthesis as the major site of action for the triacylglycerol lowering effects of inulin and oligofructose, and because this pathway is relatively inactive in man unless a high carbohydrate diet is fed, variability in response may be a reflection of differences in background diet or the experimental foods used.
Strategies for cancer prevention: the role of diet
Authors: Milner J. A.
Published: July 2006

Linkages between diet habits and cancer risk have surfaced from a multitude of epidemiological and preclinical studies. Collectively these studies provide rather compelling evidence that dietary components modify the incidence and biological behavior of tumors. While the risk of breast, prostate, colon, lung and liver cancers are frequently associated with dietary patterns, inconsistencies are not uncommon. These inconsistencies likely reflect the multi-factorial and complex nature of cancer and the specificity that individual dietary constituents have in modifying cancer related genetic pathways. The complexity of defining the role of diet is underscored by the numerous and diverse essential and non-essential components that may alter one or more phases of the cancer process. The explosive increase in the recognition of genes and pathways for regulating cell growth and development, and evaluating the response to hormones and other chemicals synthesized by the body, offers exciting opportunities for unraveling the molecular targets by which dietary components influence cancer prevention. It is recognized that all cells have unique ‘signatures’ that are characterized by active and inactive genes and cellular products. It is certainly plausible that bridging knowledge about these unique cellular characteristics with the molecular targets for nutrients can be used to assist in optimizing nutrition and minimizing cancer risk.
Technological functionality of inulin and oligofructose
Authors: Franck A.
Published: July 2006

Inulin and oligofructose are functional food ingredients which offer a unique combination of nutritional properties and important technological benefits. They are found in many vegetables and fruits and can be industrially obtained from chicory roots. In food formulations, inulin and oligofructose may significantly improve organoleptic characteristics. Their incorporation allows upgrading of both taste and mouthfeel in a wide range of food applications. Oligofructose is highly soluble and possesses technological properties that are closely related to those of sugar and glucose syrups. It is often used in combination with high intensity sweeteners. Inulin has a much lower solubility, improves the stability of foams and emulsions and shows exceptional fat-like characteristics when used under the form of a gel in water. Fat and carbohydrate replacement with chicory inulin and oligofructose offers the advantage of not compromising on taste and texture, while delivering nutritionally enhanced products.
Pet food and feed applications of inulin, oligofructose and other oligosaccharides
Authors: Flickinger E. A. , Fahey G. C.
Published: July 2006

Prebiotics may be considered as functional food ingredients. They are attracting considerable interest from pet owners, pet food manufacturers, livestock producers and feed manufacturers. The most common forms of prebiotics are nondigestible oligosaccharides (NDO), including inulin, oligofructose mannanoligosaccharides, gluco-oligosaccharides, and galacto-oligosaccharides. These NDO are nondigestible by enzymes present in the mammalian small intestine, but are fermented by bacteria present in the hindgut of nonruminants. Inulin and oligofructose are present in measurable quantities in feed ingredients like wheat, wheat by-products, barley, and peanut hulls. Consumption of prebiotic oligosaccharides elicits several purported health benefits. In companion animals, prebiotics have been shown to improve gut microbial ecology and enhance stool quality. In production livestock and poultry, prebiotics are employed to control pathogenic bacteria, reduce faecal odour, and enhance growth performance. Research to date indicates positive effects of prebiotics on health status and performance of companion animals, livestock, and poultry.
Communicating about gut health to the consumer: presenting the BENEO® Programme
Authors: Coussement P. A. A.
Published: July 2006

Providing sufficient scientific data to be able to make ‘health related claims’ on foods is quite a challenge. But bringing these claims successfully to the consumer is perhaps an even bigger challenge. Especially when the claims are based on the function of the intestinal tract, as this is a subject that not everybody communicates easily about. In our consumer research, we have focused on how the new consumer thinks and talks about gut health. We found out that he is aware of the existence and the importance of gut microflora. He believes that foods can influence his own flora. At the same time, our research has tested the efficiency of several ways to communicate about these aspects. The consumer reacts quite differently on different marketing concepts. He accepts that natural ingredients can help his gut flora and expects to find such active ingredients in common everyday foods and also in diet supplements. Based on this research, we have condensed the ‘prebiotic’ message about inulin and oligofructose into a number of simple communications. The best of these were selected for further consumer product testing. The results of this effort form the basis of the BENEO® Programme: a communication platform created by ORAFTI that allows the food industry, in partnership with ORAFTI, to bring a uniform and clear message to the consumer about the health benefits of inulin and oligofructose.
Fifteen-year time trends in energy and macronutrient intake in German children and adolescents: results of the DONALD study
Authors: Alexy Ute , Sichert-Hellert Wolfgang , Kersting Mathilde
Published: July 2006

The DONALD study (Dortmund Nutritional and Anthropometric Longitudinally Designed study) gives the opportunity to evaluate long-term food and nutrient intake data on the basis of 3 d weighed dietary records of infants, children and adolescents since 1985. In this paper, we examine changes in energy and macronutrient intakes (protein, fat, saturated, mono- and polyunsaturated fatty acids, carbohydrates and added sugars) of 795 2–18-year-old subjects between 1985 and 2000 (4483 records). No significant changes in intakes of energy and of protein, polyunsaturated fatty acids and added sugars (as % energy intake, E %) were found. Fat intake decreased significantly in all age groups (between -0·20 and -0·26 E %/year), as well as intake of saturated fatty acids (between -0·11 and -0·14 E %/year) and monounsaturated fatty acids (between -0·07 and -0·014 E %/year). This decline was compensated for by a significant increase in carbohydrate intake (between +0·18 and +0·27 E %/year). The changes in macronutrient intake were mainly due to a decreased consumption of fats–oils (between -0·29 and -1·26 g/year) and meat–fish–eggs (between -0·21 and -2·92 g/year), whereas consumption of bread–cereals (between +0·12 and +2·42 g/year) and potatoes–pasta–rice (between +0·15 and +2·26 g/year) increased slightly. However, since recommended fat intake and fatty acid composition was not reached at the end of the study period by far, further efforts will be necessary to improve macronutrient composition and to stabilize favourable dietary habits.
Menaquinone-4 in breast milk is derived from dietary phylloquinone
Authors: Thijssen H. H. W. , Drittij M.-J. , Vermeer C. , Schoffelen E.
Published: July 2006

The effect of maternal phylloquinone supplementation on vitamin K in breast milk was studied to establish: (1) if phylloquinone is the source of menaquinone-4 in breast milk; (2) the dose–effect relationship between intake and obtainable levels. Four groups of lactating mothers with a full-term healthy infant participated and took oral phylloquinone supplements of 0·0 (n8), 0·8 (n8), 2·0 (n8), and 4·0 (n7) mg/d for 12 d, starting at day 4 post-partum. Milk samples were collected on days 4, 8, 16, and 19. Blood samples were collected on days 4 and 16. Vitamin K and vitamin E concentrations, the latter for reason of comparison, were assayed. Phylloquinone and menaquinone-4 were present in all milk samples: 5·84 (SD 2·31) AND 2·98 (sd 1·51) nmol/l (n31) respectively, in colostrum (day 4 sample). A strong correlation between the vitamers was found (r0·78,P<0·001). Breast-milk phylloquinone levels were raised in a dose-dependent manner: 4-, 12-, and 30-fold on day 16 for the 0·8, 2·0, and 4·0 mg group respectively. In addition, menaquinone-4 levels were higher: 2·5- (P<0·05) and 7-fold (P<0·001) in the 2·0 and 4·0 mg groups respectively. Plasma of supplemented subjects contained 3-, 5-, and 10-fold higher phylloquinone levels on day 16. Detectable menaquinone-4 was found in ten of thirty-one day 4 plasma samples. All day 16 plasma samples of the 4 mg supplemented group contained the vitamin. There was no correlation between the K-vitamers in plasma. Vitamin E and phylloquinone appear to differ in their distribution in breast milk, milk:plasma concentration ratios were ≤1 and 3–5 for vitamin E and phylloquinone respectively. The milk:plasma concentration ratio of menaquinone-4 was >10. In conclusion, dietary phylloquinone is a source of menaquinone-4 in breast milk. Phylloquinone supplementation to lactating mothers may be of benefit to the newborn infant, since both phylloquinone and menaquinone-4 are raised by supplementation.
Functional characterization of three clones of the human intestinal Caco-2 cell line for dietary lipid processing
Authors: Salvini Séverine , Charbonnier Monique , Defoort Catherine , Alquier Christian , Lairon Denis
Published: July 2006

We aimed to improve the use of the human intestinal Caco-2 cell line for studying dietary lipid and cholesterol processing by using isolated pure clones (). Three clones (TC7, PD7 and PF11) were grown as monolayers on semi-permeable filters and compared for cell viability, fatty acid and cholesterol apical uptake or basolateral secretion, apolipoprotein B-48 basolateral secretion and 3-hydroxy-3-methylglutaryl (HMG)-CoA reductase activity. The TC7 clone showed the best viability upon apical incubation with mixed micelles and should be preferred for routine work. Short-term (3·0 h) rates of apical uptake of cholesterol were not different with the three clones, whereas the rate of apical uptake of oleic acid (18 : 1) was lower (P<0·05) with PF11 (250·6 nmol/mg) and the basolateral secretion of cholesterol and oleic acid was lower with the TC7 clone (0·40 and 29·1 nmol/mg respectively). The secretion of apolipoprotein B-48 basolaterally was about 2-fold lower than from PD7 clone. The basal levels of HMG-CoA reductase activity were significantly different (P<0·05; TC7>PF11>PD7). The down-regulation of the enzyme activity was moderate (range 13·8–21·0 %) and comparable in the presence of apical micellar cholesterol, but was much marked upon basolateral incubation with LDL (range 34·0–53·6 %), especially for the PD7 clone. In conclusion, the Caco-2 clones characterized here proved to be particularly suitable for studying lipid nutrients processing. Because these three clones exhibit some different metabolic capabilities, they provide a new tool to study intestinal response to lipid nutrients.
Effects of calcium and plant sterols on serum lipids in obese Zucker rats on a low-fat diet
Authors: Vaskonen Timo , Mervaala Eero , Sumuvuori Ville , Seppänen-Laakso Tuulikki , Karppanen Heikki
Published: July 2006

Ca may interfere with fat and cholesterol metabolism through formation of insoluble soaps with fatty and bile acids in the intestine. In the present study, we examined the effects of different dietary Ca levels on the serum lipid profile and cholesterol metabolism in obese Zucker rats fed a low-fat diet. We also tested whether dietary Ca interfered with the lipid-lowering effects of a pine oil-derived plant sterol mixture. Increase in dietary Ca intake from 0·2 to 0·8 %, and further to 2·1 % (w/w) dose-dependently decreased serum total cholesterol (r -0·565,P=0·002,n27), LDL-cholesterol (r -0·538,P=0·006,n25), and triacylglycerol (r -0·484,P=0·014,n25) concentrations, and increased HDL-cholesterol (r 0·478,P=0·016,n25) and HDL : LDL cholesterol (r 0·672,P<0·001,n25) in rats fed a 1 % cholesterol diet. Analysis of serum campesterol : cholesterol and sitosterol : cholesterol suggested that Ca dose-dependently increased intestinal cholesterol absorption (r 0·913,P<0·001,n18), whereas serum desmosterol : cholesterol and lathosterol : cholesterol indicated that Ca dose-dependently increased endogenous cholesterol synthesis (r 0·691,P=0·003,n18). Therefore, the decrease of serum LDL-cholesterol appeared to be due to Ca-induced increase in the conversion of cholesterol to bile acids. The increase in Ca intake did not interfere with the beneficial effects of plant sterols on serum total cholesterol, LDL-cholesterol and HDL-cholesterol concentrations. The high-Ca diet with plant sterol supplementation further increased the HDL-cholesterol concentration and HDL : LDL cholesterol. The present findings indicate that the beneficial effects of dietary Ca on the serum lipid profile during a low-fat diet are dose-dependent, and resemble those of bile acid sequestrants. Increased dietary Ca did not impede the lipid-lowering effects of natural plant sterols.
Effect of esterified 4-desmethylsterols and -stanols or 4,4′-dimethylsterols on cholesterol and bile acid metabolism in hamsters
Authors: Trautwein Elke A. , Schulz Claudia , Rieckhoff Dörte , Kunath-Rau Angelika , Erbersdobler Helmut F. , Arjan de Groot W. , Meijer Gert W.
Published: July 2006

4-Desmethylsterols and -stanols reduce plasma total cholesterol (TC) and LDL cholesterol by inhibition of intestinal cholesterol absorption, while the cholesterol-lowering potential of 4,4′-dimethylsterols is less well defined. The present study aimed to compare the effects of 4-desmethylsterols, -stanols, and 4,4′-dimethylsterols on plasma and hepatic cholesterol, sterol excretion and bile acid metabolism. Male golden Syrian hamsters were fed diets containing 13 g/100 g fat, 0·08 g/100 g cholesterol and 0 (control), 0·24 or 0·48 % (w/w) esterified 4-desmethylsterols (sterols) and esterified hydrogenated 4-desmethylsterols (stanols) from common vegetable oils or esterified 4,4′-dimethylsterols from rice bran oil for 5 weeks. Sterol and stanol esters at the dose of 0·24 % were equally effective and significantly (P<0·05) lowered TC by 15 %, while 0·24 % 4,4-dimethylsterols reduced TC by 10 %. Liver total and esterified cholesterol concentrations were significantly (P<0·05) lowered by 40, 22, 43 and 31 % in hamsters fed 0·48 % sterols, 0·24 % stanols, 0·48 % stanols or 0·48 % dimethylsterols, respectively. Daily faecal bile acid excretion and hepatic cholesterol 7α-hydroxylase activity were not altered, indicating that sterols, stanols and dimethylsterols had no effect on the intestinal re-absorption of bile acids or on hepatic bile acid synthesis. Daily excretion of cholesterol was significantly higher in hamsters fed esterified sterols and stanols, but was only slightly increased in those fed dimethylsterols. The results indicate that esterified sterols and stanols were equally effective in lowering plasma TC and LDL cholesterol, while dimethylsterol esters caused a weaker cholesterol-lowering effect. Sterols and stanols achieve their cholesterol-lowering effect by stimulating faecal cholesterol excretion through inhibiting intestinal cholesterol absorption, but do not affect bile acid excretion. Other mechanisms need to be considered to explain the effect on plasma and hepatic cholesterol of dimethylsterols.
n-3 Fatty acids and lipid peroxidation in breast cancer inhibition
Authors: Stoll Basil A.
Published: July 2006

Long-chain n-3 fatty acids (FA) consistently inhibit the growth of human breast cancer (BC) cells both in culture and in grafts in immunosuppressed mice. Large cohort studies have, however, failed to confirm a protective effect for fish oils rich in n-3 FA against BC risk. The present review examines new evidence on biological mechanisms which may be involved in the inhibition of mammary carcinogenesis by long-chain n-3 FA, focusing on an apoptotic effect by its lipid peroxidation products. Dietary intake of n-3 FA leads to their incorporation into cell membrane lipids. Increased apoptosis in human BC cells following exposure to long-chain n-3 FA such as eicosapentaenoic and docosahexaenoic acids is generally ascribed to their inhibition of cyclooxygenase 2 which promotes mammary carcinogenesis. In addition however, long-chain n-3 FA are particularly likely to activate peroxisome proliferator-activated receptor (PPAR)-γ, a key regulator of lipid metabolism but also capable of modulating proliferative activity in a variety of cells including mammary cells. Expression of PPAR-γ in the nucleus is activated by second messengers such as J series prostaglandins and the latter have been shown to cause apoptosis in vivo in explants of human BC cells in immunosuppressed mice. In mammary tumours, it is observed that long-chain FA not only increase apoptosis, but also increase lipid peroxidation, and the apoptotic effect can be reversed by antioxidants. The rationale for use of n-3 FA dietary supplements in counteracting BC progression needs to be tested clinically in a phase 2 pilot study, while at the same time, the effect on whole-body lipid peroxidation needs to be monitored. Dietary supplements of fish oil rich in n-3 FA are proposed for premenopausal women over the age of 40 years who are shown to be at increased BC risk. Biological markers in breast tissue of BC progression will be monitored, and observed changes related to serial plasma levels of isoprostanes as a measure of whole-body lipid peroxidation.
The comparative gastrointestinal response of young children to the ingestion of 25 g sweets containing sucrose or isomalt
Authors: Storey David M. , Lee Adam , Zumbé Albert
Published: July 2006

Sugar-free confectionery products containing the low-energy, non-cariogenic sweetener isomalt are widely available in the market place and increasingly aimed at children. However, over-consumption of such products may lead to gastrointestinal symptoms and/or osmotic diarrhoea. Little is known about the gastrointestinal tolerance of children following consumption of isomalt. The aim of the present study was to assess gastrointestinal symptoms in children following consumption of sugar-free confectionery containing isomalt compared with sweets containing sucrose. In a double-blind, randomised, controlled, crossover study, sixty-seven children aged 6–9 years ingested 25 g hard-boiled sweets containing either sucrose or isomalt on two consecutive test days. Isomalt sweets were received as enthusiastically as sucrose sweets and, when given the choice, 97 % of children asked to be given the isomalt or the sucrose sweets on the second test day. Most children did not report multiple symptoms and few experienced symptoms on both days of isomalt consumption. However, significantly more children reported stomach-ache (P<0·01), abdominal rumbling (P<0·025) and passing watery faeces (P<0·001) following consumption of isomalt sweets compared with sucrose sweets. Consumption of 25 g isomalt-containing sweets by children is not associated with significant gastrointestinal effects graded as ‘considerably more than usual’ or multiple symptoms, but is associated with a laxative effect and increase in symptoms graded as ‘slightly more than usual’. For the majority of children in the present study, 25 g isomalt-containing sweets represents an acceptable level of consumption, although some children are sensitive to the effects of isomalt ingestion.
The effect of maternal smoking and ethanol on fatty acid transport by the human placenta
Authors: Haggarty P. , Abramovich D. R. , Page K.
Published: July 2006

The role of the placenta in controlling the supply of fatty acids to the fetus was investigated in term placentas from non-smokers (n5), smokers (>ten cigarettes/d;n5) and after addition of ethanol at 2 mg/ml (n4). The maternal side was of the placenta was perfusedex vivofor 90 min with a physiological mixture of fatty acids and fatty acid:human albumin ratio. There was no effect of smoking on the transfer of linoleic (LA, 18 : 2n-6), α-linolenic (αLN, 18 : 3n-3), arachidonic (AA, 20 : 4n-6) or docosahexaenoic acid (DHA, 22 : 6n-3), expressed per perfused area (calculated from H218O exchange). However, the presence of ethanol in the perfusate at a concentration of 2 mg/ml significantly reduced (P<0·01) the absolute rate of transfer of the twon-3 polyunsaturated fatty acids, αLN and DHA. This specific effect of ethanol on αLN and DHA also resulted in an altered selectivity for transfer of individual fatty acids. In the non-smoking control group the placenta selectively transferred polyunsaturated fatty acids to the fetus in the order DHA>AA>αLN>LA. The order of selectivity was unaltered in placentas from smokers, but the addition of ethanol to the perfusion medium altered the order of selectivity to AA>αLN>LA>DHA. The presence of ethanol in the perfusate was also associated with a significant reduction (P<0·05) in the clearance of H218O. These results suggest that the presence of ethanol at a concentration of 2 mg/ml may reduce the availability of polyunsaturated fatty acids to the developing fetus.
Difference in the metabolism of vitamin K between liver and bone in vitamin K-deficient rats
Authors: Sato Toshiro , Ohtani Yutaka , Yamada Yoko , Saitoh Sanshiroh , Harada Hiroshi
Published: July 2006

The difference between vitamin K metabolism in the liver and that in the bone of vitamin K-deficient rats was examined. After 17 d administration of vitamin K-deficient food, vitamin K in the liver was almost depleted, and prothrombin time (PT) was prolonged. Serum total osteocalcin level was slightly decreased by vitamin K deficiency, whereas serum undercarboxylated osteocalcin level did not change. The level of menaquinone (MK)-4 as well as that of phylloquinone was decreased, but approximately 40 % of the initial level still existed in the femur after the 17 d period. A single-dose administration of vitamin K (250 nmol/kg body weight) markedly increased vitamin K level in the liver but not in the femur. These results suggest that the turnover of vitamin K in the bone is slower than that in the liver, and bone metabolism may be little affected by the short period of intake of vitamin K-deficient food. However, intake of a larger amount of vitamin K is required for its accumulation in the bone than in the liver. Furthermore, the counteracting effect of MK-7 on prolonged PT in vitamin K-deficient rats was found to be higher than phylloquinone or MK-4.
Digestibility and metabolic utilisation of dietary energy in adult sows: influence of addition and origin of dietary fibre
Authors: Goff G. Le , Groumellec L. Le , van Milgen J. , Dubois S. , Noblet J.
Published: July 2006

According to a 4×4 Latin square design, four adult ovariectomised sows fed at a similar energy level (516 kJ ME/kg body weight (BW)0·75per d) received one of four diets successively: a control low-dietary-fibre (DF) diet (diet C, 100 g total DF/kg DM) and three fibre-rich diets (200 g total DF/kg DM) that corresponded to a combination of diet C and maize bran (diet MB), wheat bran (diet WB), or sugar-beet pulp (diet SBP). Sows were adapted to the diet for 12 d before an 8 d measurement period. Digestibility of energy and nutrients in the diets, and total heat production (HP) and its components (fasting HP, activity HP and thermic effect of feeding (TEF), were measured. The TEF was partitioned between a short-term component (TEFst) and a long-term component (TEFlt). Total tract digestibility of nutrients and energy was greater for diet C; among the three other diets, the digestibility coefficients were higher for diet SBP than for diets MB and WB. Energy losses from CH4were linearly related to the digestible total DF intake (+1·4 kJ/g). Fasting HP at zero activity averaged 260 kJ/kg BW0·75per d. Activity HP represented 20 % total HP, or 83 kJ/kg BW0·75per d on average. Total TEF and TEFltwere higher (P<0·05) for diet WB than for the other diets. However, total HP (406 kJ/kg BW0·75per d) was not significantly affected by diet characteristics. Our results suggest that metabolic utilisation of dietary energy is little affected by the addition and origin of DF, at least under the conditions of the present study.
Differential effects ofn-3 andn-6 polyunsaturated fatty acids onBRCA1andBRCA2gene expression in breast cell lines
Authors: Bernard-Gallon Dominique J. , Vissac-Sabatier Cécile , Antoine-Vincent David , Rio Pascale G. , Maurizis Jean-Claude , Fustier Pierre , Bignon Yves-Jean
Published: July 2006

Current evidence strongly supports a role for the breast tumour suppressor genes,BRCA1andBRCA2, in both normal development and carcinogenesis.In vitroobservations reported thatBRCA1andBRCA2are expressed in a cell cycle-dependent manner. Interestingly, differences in the actions ofn-3 andn-6 polyunsaturated fatty acids have been observed: while then-3 polyunsaturated fatty acids have been described to reduce pathological cell growth, then-6 polyunsaturated fatty acids have been found to induce tumour proliferation. Here, we examined the expression ofBRCA1andBRCA2in breast cell lines after treatment with polyunsaturated fatty acids. Real-time quantitative polymerase chain reaction determinations conclusively demonstrated increases inBRCA1andBRCA2mRNA expressions in MCF7 and MDA-MB 231 tumour cell lines after treatment withn-3 polyunsaturated fatty acids (eicosapentaenoic acid and docosahexaenoic acid), but no variation was noticed with then-6 polyunsaturated fatty acid (arachidonic acid). On the other hand, no variation of the expression ofBRCA1andBRCA2mRNA was detected in MCF10a normal breast cell line treated by polyunsaturated fatty acids. The level ofBRCA1andBRCA2proteins quantified by affinity chromatography remained unchanged in tumour (MCF7, MDA-MB 231) and normal (MCF10a) breast cell lines. We suggest the presence of a possible transcriptional or post-transcriptional regulation ofBRCA1andBRCA2aftern-3 polyunsaturated fatty acid treatment in breast tumour cells.
Glutamine metabolism in ovine splanchnic tissues: effects of infusion of ammonium bicarbonate or amino acids into the abomasum
Authors: Nieto R. , Obitsu T. , Fernández-Quintela A. , Bremner D. , Milne E. , Calder A. G. , Lobley G. E.
Published: July 2006

This study investigates the effects of increased NH3or amino acid supply on glutamine utilisation and production by the splanchnic tissues of fed sheep. Six sheep, prepared with vascular catheters in the aorta, mesenteric, portal and hepatic veins, were fed grass pellets to 1·1×energy maintenance requirements. Each treatment involved a 4 d abomasal infusion, of either ammonium bicarbonate (AMM; 23·4 μmol/kg0·75per min), water (CONT), or a mixture of amino acids that excluded glutamine and glutamate (AA; 46·8 μmol amino acid-N/kg0·75per min). The treatments simulated nutritional extremes in terms of the balance of absorbed N. Kinetics across the whole gut and the liver were monitored during an intra-jugular infusion of [5-15N]glutamine. Blood flow across the whole gut or liver were unaffected by treatment. Both AMM and AA infusions doubled the hepatic release of urea-N compared with CONT (P<0·02). AA infusion decreased arterial glutamine concentration by 26 % (P<0·01) and 23 % (P<0·05) compared with AMM and CONT respectively. Despite this, whole-body glutamine flux was not affected by treatment. In contrast, AMM infusion increased hepatic glutamine production by 40 % compared with CONT (P<0·02). This provided a mechanism to ensure NH3supply to the periphery was maintained within the normal low physiological levels. Hepatic glutamine utilisation tended to increase during AA infusion, probably to ensure equal inflows of N to the ornithine cycle. Between 6 and 10 % of NH3absorbed across the digestive tract was derived from the amido-N of glutamine. Overall, splanchnic glutamine utilisation accounted for 45–70 % of whole-body glutamine flux.
Inulin and oligofructose in the dietary fibre concept
Authors: Cherbut C.
Published: July 2006

Dietary fibre consists of remnants of edible plant cell polysaccharides and associated substances resistant to hydrolysis by human alimentary enzymes, which may benefit health through a wide range of physiological effects. Inulin and oligofructose are storage carbohydrates found in a number of vegetables, fruits and whole grains. They resist digestion and absorption in the stomach and small intestine of humans, as shown by their almost full recovery at the end of the ileum of healthy or ileostomised volunteers. Inulin and oligofructose thus enter into the large intestine where they are available to fermentation, as demonstrated by increased breath hydrogen. Fermentation of both substrates is complete and no residue is found in human stools. Inulin and oligofructose improve laxation. Their bulking capacity comprised between 1·2 and 2·1 g of stool per g of ingested substrate, results mainly from increases in microbial biomass in the colon. As water content of bacterial cells is high, stools are softer and easier to expulse. Stool frequency is thus increased, particularly in slightly constipated individuals. In addition, likely due to their fermentation properties, inulin and oligofructose also affect the intestinal epithelium (trophicity, mucin expression, etc.), that may strengthen mucosal protection and reduce the risk of gastrointestinal diseases. In summary, inulin and oligofructose are plant carbohydrates, resistant to digestion in the human small intestine and fermented by colonic bacteria. They exert several intestinal physiological effects contributing to maintenance of health. Therefore, inulin and oligofructose fit well within the current concept of dietary fibre.
The effects of dietary lipids on adrenergically-stimulated lipolysis in perinodal adipose tissue following prolonged activation of a single lymph node
Authors: Mattacks Christine A. , Sadler Dawn , Pond Caroline M.
Published: July 2006

The effects of feeding beef suet (mostly saturated and monoenoic fatty acids), sunflower oil (rich inn-6 fatty acids) and fish oil (rich inn-3 fatty acids) on the response of mesenteric, omental, popliteal and perirenal adipocytes to experimentally-induced local inflammation were studied in adult guinea pigs. After 6 weeks on the experimental diets, the animals were fed standard chow, and lipopolysaccharide was injected unilaterally daily for 4 d to induce swelling of one popliteal lymph node. Basal lipolysis in the perinodal adipocytes of all depots studied was higher in the sunflower oil-fed animals than in the controls fed on standard chow, and lower in those fed on suet or fish oil. Dietary lipids altered rates of lipolysis during incubation with 10-5M noradrenaline in all samples studied from the locally-activated popliteal depot, but only in adipocytes within 5 mm of a large lymph node in the other depots. The fish-oil diet attenuated the spread of increased lipolysis within the locally-activated popliteal adipose tissue, and from this depot to other node-containing depots. These experiments show thatn-6 polyunsaturated fatty acids promote andn-3 fatty acids suppress the spread of immune activation to adipocytes within and between depots, and alter the sensitivity of perinodal adipocytes to noradrenaline. Dietary effects are reduced or absent in adipocytes in sites remote from lymph nodes, and thus such samples do not adequately represent processes in perinodal adipose tissue. These results are consistent with the hypothesis that perinodal adipocytes interact with adjacent lymphoid cells during immune responses.
Dietary supplementation with vitamin E modulates avian intestinal immunity
Authors: Muir Wendy I. , Husband Alan J. , Bryden Wayne L.
Published: July 2006

The effect of dietary vitamin E on immunoglobulin A (IgA) antibody production, which acts as the first line of defence at the intestinal mucosa, has not been evaluated in chickens. In the present study the impact of the inclusion of supplementary levels of vitamin E to the diet, on total and antigen-specific IgA antibody titres, T-cell subsets and Ia+ cells, was assessed. From hatching, chickens received a maize-based diet which was supplemented with either 25, 250, 2500 or 5000 mg dl-α-tocopherol acetate/kg. Primary immunisation with tetanus toxoid (T. toxoid) emulsified in a vegetable oil-in-water adjuvant was administered by the intraperitoneal route at 21 d of age. At 35 d of age all birds received an oral booster vaccination of T. toxoid. Significantly higher total IgA antibody titres were present in the day 42 intestinal scrapings of birds receiving the 5000 mg/kg vitamin E-supplemented diet (VESD) (P=0·05) and a notable increase was observed in birds receiving the 250 mg/kg VESD (P=0·06). At days 21 and 42 total serum IgA antibody titres of birds receiving the 250 mg/kg VESD was significantly higher (P<0·05) than the control birds. Following immunisation with T. toxoid, birds receiving the 250 and the 5000 mg/kg VESD had elevated anti-T. toxoid IgA antibody titres in final day intestinal scrapings, which, for the latter group was statistically significant (P=0·02). Both of these groups also demonstrated increased titres of anti-T. toxoid IgA in the serum at day 42. Birds receiving the 250 mg/kg VESD exhibited a notable increase in the percentage of T-helper cells and Ia+ cells in peripheral blood on day 26. The results illustrate the potential for some levels of dietary vitamin E supplementation to act as an immunomodulator of total and antigen-specific IgA antibody.
Comparison of the TriTrac-R3D accelerometer and a self-report activity diary with heart-rate monitoring for the assessment of energy expenditure in children
Authors: Rodriguez G. , Béghin L. , Michaud L. , Moreno L. A. , Turck D. , Gottrand F.
Published: July 2006

Determining total energy expenditure (EE) in children under free-living conditions has become of increasingly clinical interest. The aim of this study was to compare three different methods to assess EE triaxial accelerometry (TriTrac-R3D; Professional Products, Division of Reining International, Madison, WI, USA), activity diary and heart-rate (HR) monitoring combined with indirect calorimetry (IC). Twenty non-obese children and adolescents, aged 5.5 to 16.0 years, participated in this study. Results from the three methods were collected simultaneously under free-living conditions during the same 24 h schoolday period. Neither activity diary (5904 (SD 1756) KJ) NOR THE TRITRAC-R3D (6389 (sd 979) kJ) showed statistical differences in 24 h total EE compared with HR monitoring (5965 (sd 1911) kJ). When considering different physical activity (PA) periods, compared with HR monitoring, activity diary underestimates total EE during sedentary periods (P<0·001) and overestimates total EE and PA-EE during PA periods (P<0·001) because of the high energy cost equivalence of activity levels. The TriTrac-R3D, compared with HR monitoring, shows good agreement for assessing PA-EE during PA periods (mean difference +0·25 (sd 1·9) kJ/min; 95 % CI for the bias -0·08, 0·58), but underestimates PA-EE and it does not show good precision during sedentary periods (-0·87 (sd 1·4) kJ/min, P<0·001). Correlation between the vector magnitude generated by the TriTrac-R3D accelerometer and EE of activities derived from HR monitoring is high. When compared with the HR method, the TriTrac-R3D and activity diary are not systematically accurate and must be carefully used for the assessment of children's EE depending on the purpose of each study.
Insulin-like growth factor-I and analogues increase growth in artificially-reared neonatal pigs
Authors: Dunshea Frank R. , Chung Chung S. , Owens Phil C. , Ballard John F. , Walton Paul E.
Published: July 2006

Exogenous insulin-like growth factor (IGF)-I has been shown to increase growth rate in neonatal pigs while an analogue of IGF-I, long arginine (LR3) IGF-I, has been shown to be more potent than IGF-I in the rat. Therefore, two studies were conducted to determine whether IGF-I and LR3IGF-I increase growth in the artificially-reared neonatal pig. Expt 1 involved forty-two (2 kg initial weight) pigs infused with either control, IGF-I (2, 4 or 8 μg/h) or LR3IGF-I (2, 4 or 8 μg/h) infusions for 8 d. Pigs were weighed and then offered 1·7 MJ (gross energy) milk replacer/kg0·75per d. Expt 2 involved eighteen pigs (2 kg initial weight) treated with control saline, IGF-I (8 μg/h) or LR3IGF-I (8 μg/h) infusions. After 9 d an additional pump was inserted to increase the infusion rates of each of the growth factors (16 μg/h) for a further 9 d. Cows' milk was providedad libitum. In Expt 1 there was no overall effect of growth factors on daily weight gain or slaughter weight. However, milk intake was greater in pigs infused with growth factors (909v.867 g/d,P=0·027), with an apparently greater milk intake by the pigs infused with IGF-I compared with LR3IGF-I (920v.898 g/d,P=0·12). Infusion of LR3IGF-I decreased plasma IGF-I concentrations, but had no effect on plasma IGF-II concentrations. In Expt 2, neither IGF-I nor LR3IGF-I infusion had any effect upon daily weight gain over the first 9 d of the study. However, over the second 9 d of the study, daily weight gain was increased in LR3IGF-I-infused pigs (457v.386 g/d,P<0·01), but not in pigs infused with IGF-I (413v.386 g/d,P=0·15). Milk intake was not different during the first 9 d of the study but was significantly greater in pigs infused with growth factors over the second half of the study (3407v.2905 g/d,P<0·01). Plasma IGF-binding protein-3 concentrations were highly correlated (R=0·85) with average daily gain over the 3 d preceding blood sampling. In conclusion, exogenous IGF-I and particularly LR3IGF-I can increase growth rate and milk intake in artificially-reared pigs fedad libitumbut not in limit-fed piglets.
Differences in iron requirements by concanavalin A-treated and anti-CD3-treated murine splenic lymphocytes
Authors: Kuvibidila Solo R. , Velez Maria , Yu Lolie , Warrier Raj P. , Baliga B. Surendra
Published: July 2006

Fe availability is critical for optimal lymphocyte proliferation; however, the minimum required levels are unknown. Such information is valuable when assessingin vitroimmune responses in Fe-deficient subjects, because serum (Fe) added to the culture medium may replete lymphocytes. To address this issue, splenic lymphocytes obtained from seventeen 3-month-old C57BL/6 mice were incubated without and with 1 mg/l concanavalin A or 50 μg/l anti-CD3 antibody in media that contained between 0·113 and 9·74 μmol Fe/l. Fe was provided by either fetal calf serum (FCS, 0–100 ml/l), newborn calf serum (NBCS, 0–100 ml/l), or NBCS (10 ml/l) plus ferric ammonium citrate. As expected, the rate of DNA synthesis increased with Fe levels (P<0·01). Maximum DNA synthesis was obtained with 2·26 μmol Fe/l (50 ml FCS/l) for concanavalin A and 0·895 μmol/l (20 ml FCS/l) for anti-CD3-treated cells. In serum-free media (0·113 μmol Fe/l), the proliferative responses to concanavalin A were below the background, while they rose 5·5-fold in anti-CD3-treated cells (P<0·05). In apotransferrin-supplemented media (0·13 μmol Fe/l), the proliferative responses to concanavalin A and anti-CD3 antibody were 18·6 and 71 %, respectively, of that obtained with 4·66 μmol Fe/l (100 ml FCS/l). Interleukin 2 secretion also followed the same trend as lymphocyte proliferation. Since differences between both mitogens persisted after FCS was substituted with NBCS, we can rule out an effect on ribonucleotide reductase activity, or by other serum growth factors. We speculate an Fe effect at an early step of T-cell activation. Data suggest that the minimum Fe concentration required for lymphocyte proliferation varies with the mitogen.
Parenteral iron therapy in obstetrics: 8 years experience with iron–sucrose complex
Authors: Perewusnyk G. , Huch R. , Huch A. , Breymann C.
Published: July 2006

Fe is an essential component of haem in myoglobin and accounts for 70 % of haemoglobin. The balance of Fe, unlike that of other metals such as Na or Ca, is regulated solely by gastrointestinal absorption, which itself depends on the bioavailability of Fe in food, i.e. the chemical Fe species. Factors that maintain Fe homeostasis by modulating Fe transfer through the intestinal mucosa are found at the luminal, mucosal and systemic levels. Fe deficiency and its consequence, Fe-deficiency anaemia, form the commonest nutritional pathology in pregnant women. The current gold standard to detect Fe deficiency remains the serum ferritin value. Previously there was general consensus against parenteral Fe administration, i.e. parenteral Fe was only recommended for special conditions such as unresponsiveness to oral Fe, intolerance to oral Fe, severe anaemia, lack of time for therapy etc. However, especially in hospital settings, clinicians regularly face these conditions but are still worried about reactions that were described using Fe preparations such as Fe–dextrans. A widely used and safe alternative is the Fe–sucrose complex, which has become of major interest to prevent functional Fe deficiency after use of recombinant erythropoietin Numerous reports show the effectiveness and safety of the Fe–sucrose complex. Good tolerance to this Fe formulation is partly due to the low allergenic effect of the sucrose complex, partly due to slow release of elementary Fe from the complex. Accumulation of Fe–sucrose in parenchyma of organs is low compared with Fe–dextrans or Fe–gluconate, while incorporation into the bone marrow for erythropoiesis is considerably faster. Oral Fe is only started if haemoglobin levels are below 110 g/l. If levels fall below 100 g/l or are below 100 g/l at time of diagnosis, parenteral Fe–sucrose is used primarily. In cases of severe anaemia (haemoglobin <90 g/l) or non-response to parenteral Fe after 2 weeks, recombinant erythropoietin is considered in combination. By using parenteral Fe–sucrose in cases of severe Fe deficiency, anaemia during pregnancy is treated efficiently and safely according to our results and rate of blood transfusion could be reduced considerably to below 1 % of patients per year.