Effect of stage of lactation and dietary starch content on endocrine-metabolic status, blood amino acid concentrations, milk yield, and composition in Holstein dairy cows.

Milk yield and composition are modified by level and chemical characteristics of dietary energy and protein. Those factors determine nutrient availability from a given diet, and once absorbed, they interact with the endocrine system and together determine availability of metabolites to the mammary gland. Four multiparous dairy cows in early lactation and subsequently in late lactation were fed 2 diets for 28 d in a changeover design that provided, within the same stage of lactation, similar amounts of rumen fermentable feed with either high (HS) or low starch (LS). All diets had similar dietary crude protein (15.5% dry matter) and rumen-undegradable protein (∼40% of crude protein) content. Profiles of AA were calculated to be similar to that of casein. On d 28, [1-13C] Leu was infused into one jugular vein with blood samples taken at 0, 2, 4, 6, and 8 h, and cows milked at 0, 2, 4, 5, 6, 7, and 8 h from start of infusion. Isotopic enrichments of plasma Leu, keto-isocaproic acid, and milk casein were determined for calculation of Leu kinetics. Data were subjected to ANOVA using the MIXED procedure of SAS (SAS Institute Inc.), with time as repeated factor and cow as the random effect. Dry matter intake within each stage of lactation was similar between groups. Feeding LS resulted in lower blood glucose and greater ratio of bovine somatotropin to insulin. This response was associated with greater blood concentrations of nonesterified fatty acids and ß-hydroxybutyrate, which might have contributed to greater milk fat content in LS-fed cows. Except for His, average concentrations of all AA in blood were higher in late than early lactation. Diet did not alter average plasma concentrations of AA. However, for most of the essential AA (particularly branched-chain), the HS diet led to a marked decrease in concentrations after the forage meal, resulting in significant differences between dietary groups in early lactation. In early-lactating cows fed HS, a greater reduction in plasma concentrations at 8 h relative to pre-feeding values (time zero) was observed for Met, Lys, and His, resulting in decreases of 27.9%, 33.6%, and 38.5%, respectively. A higher bovine somatotropin/insulin ratio in early lactation and in cows fed LS could possibly have led to greater breakdown and, consequently, higher AA flux from peripheral tissues. In LS-fed cows, higher mobilization of body fat and protein was confirmed by the greater body weight loss in both stages of lactation. Higher irreversible loss of [1-13C] Leu in early lactation suggested lower protein retention in peripheral tissues during early compared with late lactation. Milk yield, protein output, and composition were similar between groups at both stages of lactation, whereas milk coagulation was faster (lower curd firming rate) and with higher curd firmness in response to feeding HS in late lactation. Overall, data indicated that rate of carbohydrate fermentability in the rumen can modify the availability of metabolites to the mammary gland and consequently modify milk protein coagulation.

Impacts of operating conditions on efficiency of electrokinetically enhanced filtration for de-watering of orange juice and malt extract.

The effects of operational factors an on an electrokinetic-enhanced filtration (EKEF) application to dewater orange juice (OJ) and malt extract (ME) was investigated. EKEF improved dewatering of both foodstuffs and resulted in net dewatering efficiencies of 7.4% and 4.9% for OJ and 10.7% and 6.3% for ME after 5.5 h processing under 30 V and 15 V, respectively. Dry matter content was increased by 19.2% and 15.6% for OJ after 5.5 h and 14.8% and 12.8% for ME after 3.5 h under 30 V and 15 V, respectively, compared with 14.9% and 10.3% under the control conditions for OJ and ME, respectively. The EKEF process effectively improved dewatering of high moisture-content foods with positive impacts on process efficiency by increased voltage, pressure, and the pore size of filters. The initial distance between electrodes had a negative impact as the distance increased. EKEF is a useful adjunct to improve high pressure filtration of foodstuffs.

Discharged filtrate movement in food materials under application of electrokinetics.

Orange juice (OJ) and malt extract (ME) samples were treated using an electrokinetic (EK) application to investigate the impact of the pH/Lowest conductivity point (LCP) ratio of experimental materials on the water profile direction and the anolyte to catholyte filtrate ratio. After applying the electric field through samples between two electrodes, filtrate was discharged mainly towards the anode in OJ samples (acidic medium, pH/LCP < 1) and towards the cathode in ME samples (alkaline medium, pH/LCP > 1). Adjusting the orientation of electrodes depending on the results maximised dewatering efficiency under EK by 7.8% in OJ and 11.8% in ME. Changing the pH/LCP ratio by adjusting the starting pH improved dewatering efficiency under EK by 25.7%. The results are used to develop theoretical guidelines to help determine the water profile direction and filtrate outlets for different food materials based on their pH and LCP values. EK is an effective method for dewatering food materials.

Effect of dietary starch level and high rumen-undegradable protein on endocrine-metabolic status, milk yield, and milk composition in dairy cows during early and late lactation.

Diet composition defines the amount and type of nutrients absorbed by dairy cows. Endocrine-metabolic interactions can influence these parameters, and so nutrient availability for the mammary gland can significantly vary and affect milk yield and its composition. Six dairy cows in early and then late lactation received, for 28 d in a changeover design, 2 diets designed to provide, within the same stage of lactation, similar amounts of rumen fermentable material but either high starch plus sugar (HS) content or low starch plus sugar content (LS). All diets had similar dietary crude protein and calculated supply of essential amino acids. Dry matter intake within each stage of lactation was similar between groups. Milk yield was similar between groups in early lactation, whereas a higher milk yield was observed in late lactation when feeding HS. At the metabolic level, the main difference observed between the diets in both stages of lactation was lower blood glucose in cows fed LS. The lower glucose availability during consumption of LS caused substantial modifications in the circulating and postprandial pattern of metabolic hormones. Feeding LS versus HS resulted in an increase in the ratio of bovine somatotropin to insulin. This increased mobilization of lipid reserves resulted in higher blood concentrations of nonesterified fatty acids and ß-hydroxybutyrate, which contributed to the higher milk fat content in both stages of lactation in the LS group. This greater recourse to body fat stores was confirmed by the greater loss of body weight during early lactation and the slower recovery of body weight in late lactation in cows fed LS. The lower insulin to glucagon ratio observed in cows fed LS in early and late lactation likely caused an increase in hepatic uptake and catabolism of amino acids, as confirmed by the higher blood urea concentrations. Despite the higher catabolism of amino acids in LS in early lactation, similar milk protein output was observed for both diets, suggesting similar availability of amino acids for peripheral tissue and mammary gland. The latter could be the result of sparing of amino acids at the gut level due to starch that escaped from the rumen, and to the balanced amino acid profile of digestible protein. This last aspect appears worthy of further research, with the aim to enhance the efficiency of protein metabolism of dairy cows, reducing environmental nitrogen pollution without affecting milk yield potential.

Improving the fatty acid profile of winter milk from housed cows with contrasting feeding regimes by oilseed supplementation.

Many studies show concentrations of nutritionally desirable fatty acids in bovine milk are lower when cows have no access to grazing, leading to seasonal fluctuations in milk quality if cows are housed for part of the year. This study investigated the potential to improve the fatty acid profiles of bovine milk by oilseed supplementation (rolled linseed and rapeseed) during a period of indoor feeding in both organic and conventional production systems. Both linseed and rapeseed increased the concentrations of total monounsaturated fatty acids, vaccenic acid, oleic acid and rumenic acid in milk, but decreased the concentration of the total and certain individual saturated fatty acids. Linseed resulted in greater changes than rapeseed, and also significantly increased the concentrations of α-linolenic acid, total polyunsaturated fatty acids and total omega-3 fatty acids. The response to oilseed supplementation, with respect to increasing concentrations of vaccenic acid and omega-3 fatty acids, appeared more efficient for organic compared with conventional diets.

Impact of a customised dietary intervention on antioxidant status, dietary intakes and periodontal indices in patients with adult periodontitis.

BACKGROUND: Dietary modification may be important in the prevention and control of chronic adult periodontitis. The role of promoting an adequate consumption of fruits, vegetables and whole grains in chronic periodontitis has not been thoroughly investigated. The main aim of this dietary intervention study was to assess the influence of a customised dietary intervention (aiming to increase the consumption of fruits, vegetables and whole grains) on antioxidant status in adults with chronic periodontitis. METHODS: Fifty-one participants, aged 30-65 years, were recruited from a U.K. Dental Hospital and randomly allocated to an intervention or control group. Both groups received normal clinical treatment but customised dietary advice was delivered to the intervention group by a community nutrition assistant. Dietary intakes, anthropometric parameters and biochemical indices with respect to blood and saliva and periodontal indices were evaluated at baseline, as well as at 3 and 6 months post-dietary intervention. RESULTS: At 3 and 6 months post-intervention, the intervention group showed a significant (P < 0.05) increase in plasma total antioxidant capacity measured by Trolox equivalent antioxidant capacity assay compared to the control group. At 3 and 6 months after dietary intervention, the intervention group had significantly higher intakes of fruits and vegetables compared to the control group. The intake of whole grain was significantly higher in the intervention group than in the control group, 6 months post-intervention. No significant differences were observed with respect to periodontal indices between groups. CONCLUSIONS: It is suggested that dietary advice may help to improve dietary habits and, consequently, the antioxidant status of patients with chronic periodontitis. However, the impact of such intervention on periodontal indices needs further investigation.

Variation in nutritionally relevant components in retail Jersey and Guernsey whole milk.

This study investigates the quality of retail milk labelled as Jersey & Guernsey (JG) when compared with milk without breed specifications (NS) and repeatability of differences over seasons and years. 16 different brands of milk (4 Jersey & Guernsey, 12 non specified breed) were sampled over 2 years on 4 occasions. JG milk was associated with both favourable traits for human health, such as the higher total protein, total casein, α-casein, ß-casein, κ-casein and α-tocopherol contents, and unfavourable traits, such as the higher concentrations of saturated fat, C12:0, C14:0 and lower concentrations of monounsaturated fatty acids. In summer, JG milk had a higher omega-3:omega-6 ratio than had NS milk. Also, the relative increase in omega-3 fatty acids and α-tocopherol, from winter to summer, was greater in JG milk. The latter characteristic could be of use in breeding schemes and farming systems producing niche dairy products. Seasonality had a more marked impact on the fatty acid composition of JG milk than had NS milk, while the opposite was found for protein composition. Potential implication for the findings in human health, producers, industry and consumers are considered.

Do implant-supported dentures facilitate efficacy of eating more healthily?

UNLABELLED: Edentulous persons have poor diet quality demonstrating a need for dietary intervention. Implant-supported mandibular overdentures (IODs) have functional advantages over conventional dentures (CD), but whether they enhance the ability to eat more healthily following dietary advice is unknown. OBJECTIVES: This study aimed to compare the effectiveness of dietary intervention between IODs and CD patients. METHODS: Edentulous adults (28 IOD and 26 CD) received customised dietary advice. The percentage contribution of dietary fats, carbohydrate and protein to energy (kcal) intake, dietary intakes of fibre, fruits, vegetables and antioxidants, and plasma antioxidants were assessed pre- and at 3 and 6 months post-dietary intervention. RESULTS: Both groups increased fruit and vegetable intake at 3 and 6 months following dietary intervention but intakes between groups did not differ. The IOD group had reduced % energy from total fat at 3 and 6 months and from saturated fat at 3 months. The CD group had reduced % energy from saturated by 6 months. The IOD group had a significantly lower % energy intake from saturated fat at 3 months and higher intake of non-starch polysaccharide (NSP) compared with the CD group. Both groups showed improvements in serum antioxidant status but the IOD group had significantly higher plasma antioxidant capacity post intervention compared with the CD group. CONCLUSIONS: Dietary intervention benefits denture patients. IOD patients showed moderately greater dietary improvements compared with conventional denture patients.

Randomized clinical trial of omega-3 fatty acid-supplemented enteral nutrition versus standard enteral nutrition in patients undergoing oesophagogastric cancer surgery.

BACKGROUND: Oesophagogastric cancer surgery is immunosuppressive. This may be modulated by omega-3 fatty acids (O-3FAs). The aim of this study was to assess the effect of perioperative O-3FAs on clinical outcome and immune function after oesophagogastric cancer surgery. METHODS: Patients undergoing subtotal oesophagectomy and total gastrectomy were recruited and allocated randomly to an O-3FA enteral immunoenhancing diet (IED) or standard enteral nutrition (SEN) for 7 days before and after surgery, or to postoperative supplementation alone (control group). Clinical outcome, fatty acid concentrations, and HLA-DR expression on monocytes and activated T lymphocytes were determined before and after operation. RESULTS: Of 221 patients recruited, 26 were excluded. Groups (IED, 66; SEN, 63; control, 66) were matched for age, malnutrition and co-morbidity. There were no differences in morbidity (P = 0·646), mortality (P = 1·000) or hospital stay (P = 0·701) between the groups. O-3FA concentrations were higher in the IED group after supplementation (P < 0·001). The ratio of omega-6 fatty acid to O-3FA was 1·9:1, 4·1:1 and 4·8:1 on the day before surgery in the IED, SEN and control groups (P < 0·001). There were no differences between the groups in HLA-DR expression in either monocytes (P = 0·538) or activated T lymphocytes (P = 0·204). CONCLUSION: Despite a significant increase in plasma concentrations of O-3FA, immunonutrition with O-3FA did not affect overall HLA-DR expression on leucocytes or clinical outcome following oesophagogastric cancer surgery. REGISTRATION NUMBER: ISRCTN43730758 (http://www.controlled-trials.com).

In vitro protective effects of colon-available extract of Camellia sinensis (tea) against hydrogen peroxide and beta-amyloid (Aß((1-42))) induced cytotoxicity in differentiated PC12 cells.

There is mounting evidence that the deposition and aggregation of ß-amyloid peptides (Aß) in the brain play a significant role in the development and pathogenesis of Alzheimer's disease. There is further evidence that free radical species such as hydrogen peroxide (H(2)O(2)) mediate Aß induced toxicity. Previous studies have demonstrated that green tea polyphenols possess neuroprotective properties through their ability to ameliorate oxidative stress induced by free radical species. Green tea polyphenols have also been shown to enhance cognition in various animal models of induced cognitive impairment. Upon ingestion, green tea polyphenols are metabolised and undergo bio-transformation which affects their bioavailability and therefore efficacy. In this study, a green tea extract was subjected to a simulated gastrointestinal digestion and a 'colon-available' extract (CAGTE) prepared and assessed for its potential protective effects against H(2)O(2) and Aß((1-42)) induced cytotoxicity using differentiated PC12 cells (dPC12) as a model for neuronal cells. CAGTE represents green tea phytochemicals potentially available after upper gastrointestinal digestion. CAGTE which was depleted in flavan-3-ols, as shown by LC-MS analysis, protected dPC12 cells at concentration ranges of 0.3-10 µg/ml and 0.03-0.125 µg/ml for H(2)O(2) and Aß((1-42)), induced cytotoxicity, respectively. At high concentrations, CAGTE exhibited direct anti-proliferative effects, in line with the reputed anti-cancer properties of green tea polyphenols. These results demonstrate that potentially bioavailable green tea metabolites are able to ameliorate both H(2)O(2) and Aß((1-42)) induced cytotoxicity.

In vitro protective effects of Withania somnifera (L.) dunal root extract against hydrogen peroxide and ß-amyloid(1-42)-induced cytotoxicity in differentiated PC12 cells.

Withania somnifera L. Dunal (Solanaceae), also known as 'ashwagandha' in Sanskrit and as 'Indian ginseng', is used widely in Ayurvedic medicine as a nerve tonic and memory enhancer, with antiaging, antistress, immunomodulatory and antioxidant properties. There is a paucity of data on the potential neuroprotective effects of W. somnifera root, as traditionally used, against H(2)O(2)- and Aß((1-42))-induced cytotoxicity which are current targets for novel approaches to treat dementia, especially dementia of the Alzheimer's type (AD). In this study, an aqueous extract prepared from the dried roots of W. somnifera was assessed for potential protective effects against H(2)O(2)- and Aß((1-42))-aggregated fibril cytotoxicity by an MTT assay using a differentiated rat pheochromocytoma PC12 cell line. The results suggest that pretreatments of differentiated PC12 cells with aqueous extracts of W. somnifera root significantly protect differentiated PC12 cells against both H(2)O(2)- and Aß((1-42))-induced cytotoxicity, in a concentration dependent manner. To investigate the compounds that could explain the observed effects, the W. somnifera extract was analysed by liquid chromatography-serial mass spectrometry and numerous withanolide derivatives, including withaferin A, were detected. These results demonstrate the neuroprotective properties of an aqueous extract of W. somnifera root and may provide some explanation for the putative ethnopharmacological uses of W. somnifera for cognitive and other neurodegenerative disorders that are associated with oxidative stress.

Neonatal lamb vigour is improved by feeding docosahexaenoic acid in the form of algal biomass during late gestation.

To determine whether feeding a sustainable, algal source of docosahexaenoic acid (DHA) to sheep during late pregnancy would improve neonatal lamb vigour, 48 English mule ewes, of known conception date, were divided into four treatment groups. For the last 9 weeks of gestation, ewes received one of two dietary supplements: either a DHA-rich algal biomass providing 12 g DHA/ewe per day, or a control supplement based on vegetable oil. The four dietary treatment groups (n = 12) were: control supplement for the duration of the trial (C), DHA supplement from 9 to 6 weeks before parturition (3 week), DHA supplement from 9 to 3 weeks before parturition (6 week) and DHA supplement for the duration of the trial (9 week). Dietary supplements were fed alongside grass silage and commercial concentrate. There was a tendency for gestation length to be extended with increased duration of DHA supplementation (P = 0.08). After parturition, the concentrations of eicosapentaenoic acid (EPA) and DHA in ewe and lamb plasma and colostrum were elevated in line with increased periods of DHA supplementation. Lambs from the 6-week and 9-week groups stood significantly sooner after birth than lambs from the C group (P < 0.05). These data show that neonatal vigour may be improved by the supplementation of maternal diets with DHA-rich algal biomass and that this beneficial effect depends upon the timing and/or duration of DHA allocation.

Whole-grain intake of British young people aged 4-18 years.

Inverse associations between whole-grain food consumption and risk of CVD, some cancers and type 2 diabetes have been reported. However, there are few reports of whole-grain intake, particularly among young people. The objective of the present study was to estimate whole-grain intake in a nationally representative sample of young people aged 4-18 years living in Great Britain. Whole-grain intake was estimated using 7 d weighed dietary records from 1583 young people who participated in the cross-sectional National Diet and Nutrition Survey in 1997. Whole-grain intake was quantified from the consumption of all foods containing > or =10 % whole-grain content. Median whole-grain intake was 7 g/d (interquartile range 0-19 g/d), with a corresponding mean of 13 (sd 18) g/d. Intake was significantly lower among young people whose head of household had a manual occupation, but did not differ significantly by sex, age, region or season. There was no whole-grain intake for 27 % of participants. The percentages for less than one and less than three 16 g amounts of whole-grain intake per d were 70 and 94, respectively, while corresponding percentages based on 20 g amounts were 76 and 97. Foods with <51 % whole-grain content provided 28 % of whole-grain intake overall, with a higher percentage in older adolescents. The main sources of whole-grain intake were breakfast cereals (56 %) and bread (25 %). The present study provides the first quantification of absolute whole-grain intake from all significant food sources in any representative age group in the UK. Although there is some debate regarding the quantity of whole grains required for good health, whole-grain intake among British young people is low.

Influence of dietary factors on the clinical course of ulcerative colitis: a prospective cohort study.

BACKGROUND AND AIMS: The causes of relapses of ulcerative colitis (UC) are unknown. Dietary factors have been implicated in the pathogenesis of UC. The aim of this study was to determine which dietary factors are associated with an increased risk of relapse of UC. METHODS: A prospective cohort study was performed with UC patients in remission, recruited from two district general hospitals, who were followed for one year to determine the effect of habitual diet on relapse. Relapse was defined using a validated disease activity index. Nutrient intake was assessed using a food frequency questionnaire and categorised into tertiles. Adjusted odds ratios for relapse were determined using multivariate logistic regression, controlling for non-dietary factors. RESULTS: A total of 191 patients were recruited and 96% completed the study. Fifty two per cent of patients relapsed. Consumption of meat (odds ratio (OR) 3.2 (95% confidence intervals (CI) 1.3-7.8)), particularly red and processed meat (OR 5.19 (95% CI 2.1-12.9)), protein (OR 3.00 (95% CI 1.25-7.19)), and alcohol (OR 2.71 (95% CI 1.1-6.67)) in the top tertile of intake increased the likelihood of relapse compared with the bottom tertile of intake. High sulphur (OR 2.76 (95% CI 1.19-6.4)) or sulphate (OR 2.6 (95% CI 1.08-6.3)) intakes were also associated with relapse and may offer an explanation for the observed increased likelihood of relapse. CONCLUSIONS: Potentially modifiable dietary factors, such as a high meat or alcoholic beverage intake, have been identified that are associated with an increased likelihood of relapse for UC patients. Further studies are needed to determine if it is the sulphur compounds within these foods that mediates the likelihood of relapse and if reducing their intake would reduce relapse frequency.

Behavioural, attitudinal and dietary responses to the consumption of wholegrain foods.

Whole grains are important dietary constituents as they provide a plethora of nutrients and protective chemicals that may have synergistic actions in promoting health. Regular consumption of wholegrain foods has been associated with a reduced risk of several chronic diseases such as CHD and certain cancers, although their exact role in disease prevention is not yet fully elucidated. Studies reporting levels of whole grain consumption reveal that those subjects who include higher levels of whole grain foods in their diets also have many other favourable dietary and lifestyle practices. While the actions of these practices and whole grains may not be mutually exclusive, these variables do not appear to explain the reduction in risk of disease observed for high-whole grain consumers. Actual whole grain consumption levels are extremely low and many practical barriers exist to consumer uptake of these foods. Effective communication of the whole grain health message is an important strategy to increase awareness of the importance of whole grains in the diet. Increasing the variety and availability of acceptable wholegrain foods is also important. Whole grain consumption at breakfast can have an important impact on total daily nutrient intakes. This simple dietary modification is potentially relatively easy to achieve and could greatly contribute to increased whole grain intake for many individuals.

Defining relapse of ulcerative colitis using a symptom-based activity index.

BACKGROUND: Several tools exist to assess disease activity in patients with ulcerative colitis (UC), but a definition of relapse does not exist. The aim of the study was to determine the score in the Simple Clinical Colitis Activity Index (SCCAI) that defined relapse. The reliability and validity of the SCCAI when self-administered was also examined. METHODS: Patients with UC routinely attending hospital completed the SCCAI questionnaire, which was later administered by their clinician blinded to the scoring process. In the absence of a gold standard definition of relapse, a subjective global assessment of disease status was made by the clinician. The SCCAI was evaluated in a separate cohort of patients. RESULTS: Seventy-one presentations were analysed; mean age 48 years, 49% male, 37% relapse rate. The mean patient score was 4.2 (range 0-14) and mean physician score 3.8 (0-14). A score of 5 or more defined relapse with 92% sensitivity, 93% specificity, 88% positive predictive value and 95% negative predictive value. The difference between the scores obtained by the patient and clinician (0.35, 95% CI 0.09-0.62) was small. Correlation with a more complex symptom and laboratory-based activity index was very high (r = 0.79, P < 0.01). The index was quick to use and comparative results for sensitivity and specificity were recorded in the second cohort of patients. CONCLUSIONS: The SCCAI is a simple tool that can be accurately and quickly self-administered, correlates well with a more complex disease activity index, and can be used to define relapse of UC with high specificity and sensitivity.

The short inflammatory bowel disease questionnaire is reliable and responsive to clinically important change in ulcerative colitis.

OBJECTIVE: The Short Inflammatory Bowel Disease Questionnaire (SIBDQ) is a health-related quality of life (HRQoL) tool measuring physical, social, and emotional status (score 10-70, poor to good HRQoL). The SIBDQ has been predominantly used in trials for Crohn's disease, and further validation of the SIBDQ is desirable in ulcerative colitis (UC) patients. The primary objective was to further validate the SIBDQ by examining discriminant ability against measures of disease activity. The secondary objectives were to examine reliability and responsiveness to change. METHODS: UC patients attending hospital completed the SIBDQ and two activity indices. Patients' disease status (remission, mild, moderate, or severe relapse) was determined subjectively by the patients and their physician. RESULTS: Scores were obtained for 69 events in 61 patients. mean age 47.8 yr (range 16-79). All classes of disease extent were represented. The mean SIBDQ score was 48.4 (13-70). The difference between mean score in patients in remission and relapse was -20.1 (95% CI = -25.1 to -15.1). The difference for remission and mild relapse was -14.6 (95% CI = -8.9 to -20.2). The correlation between SIBDQ and the activity indices were good, r = -0.83 and r = -0.61. Eight patients presented twice. Those with unchanged disease status showed no significant difference in the mean SIBDQ score. Patients whose disease status had deteriorated from remission to mild relapse, or from mild to moderate relapse demonstrated a mean reduction of 11.8 points (95% CI = 20.1-3.4). CONCLUSIONS: This study contributes to the validation of the SIBDQ as a HRQoL tool in UC. It is reproducible and responsive to changes in disease activity.

Comparative gastrointestinal and plasma cholesterol responses of rats fed on cholesterol-free diets supplemented with guar gum and sodium alginate.

The present study investigated the digestion and cholesterol-lowering effects of the water-soluble NSP guar gum (GG) and sodium alginate (SA) in laboratory animals. Groups of five male Wistar strain rats were fed semi-purified cholesterol-free diets containing 0, 50 or 100 g NSP source/kg for 21 d which comprised a 14-d adaptation period followed by a 7-d balance period. Weight gain over the balance period and food conversion ratio decreased linearly with increasing NSP intake ( and respectively). DM digestibility decreased with increasing NSP intake and this effect was greater for SA-containing diets compared with GG-containing diets At the lower inclusion rate, 0.9-1.0 of the additional NSP was digested, but this value fell to 0.8 for both NSP sources at the 100 g/kg inclusion rate, implying that the capacity for near complete digestion of the test NSP had been exceeded. Intestinal tissue mass was increased in response to inclusion of both NSP sources. Caecal digesta pH decreased linearly with additional GG, but increased slightly with consumption of SA. Total caecal short-chain fatty acid concentrations (micromol/g caecal contents) increased markedly with 50 g GG/kg but did not increase further with 100 g GG/kg, and were slightly lower than control values in rats consuming SA. Plasma cholesterol concentration fell linearly with increasing NSP in the diet and the effect was similar for both GG and SA. Total output of faecal bile acids rose in rats fed 50 g GG/kg and 50 g SA/kg (59 micromol/7 d v. 24 micromol/7 d for control rats) with no further increase at the higher inclusion rate. These results show that SA has a strong hypocholesterolaemic effect in rats which is similar to that of GG, and that this effect is most likely to be mediated through an interruption in the entero-hepatic circulation of bile acids and not through increased hepatic supply of propionate from fermentation of the NSP in the large bowel.

Glucose and [13C]leucine metabolism by the portal-drained viscera of sheep fed on dried grass with acute intravenous and intraduodenal infusions of glucose.

The effect of exogenous glucose supply by either intrajugular (IJG) or intraduodenal (IDG) infusion at 2.0 mg glucose/kg body weight per min was investigated in four wether sheep (average weight 44 (SD 4) kg) chronically catheterized in the carotid artery and portal veins. Sheep were fed on a dried grass pellet diet hourly using continuous belt feeders. Whole-body glucose irreversible loss (IL) rate, measured with [6-3H]glucose, was increased by 0.5 and 0.8 of exogenous supply for IJG and IDG infusions respectively. Portal glucose utilization, measured by isotope dilution across the portal-drained viscera, was unaffected by additional glucose regardless of the route of glucose supply (P = 0.76 for control v. glucose infusions) and was a constant proportion of glucose IL (0.28) for all treatments. Portal plasma flow was higher during IDG infusions compared with IJG infusions (1.65 v. 1.44 litres/min, P = 0.055). Circulating total free amino acid concentrations fell during glucose infusions (2146, 1808 and 1683 mumol/l for control, IJG and IDG treatments respectively, P = 0.067 for treatment effect) but net portal absorption was not affected by increased glucose supply. Recovery in the portal vein of [1-13C]leucine infused into the duodenum averaged 0.65 and was not affected by increasing glucose supply to the gut tissues. The results show that glucose utilization by gut tissues is responsive to changes in both vascular and luminal glucose supply. The effects of changing gut tissue use of glucose and increased whole body glucose IL on metabolism of nutrients is discussed.