The effects of monensin in diets fed to finishing beef steers and heifers on growth performance and fecal shedding of Escherichia coli O157:H7.

Two experiments were conducted to study the effects of monensin dose on growth performance and O157:H7 shedding in finishing beef cattle. In Exp. 1, 198 heifers (298 ± 1.1 kg BW) were allocated to 1 of 2 treatments consisting of 1) 200 mg/heifer daily of monensin and 2) 400 mg/heifer daily of monensin and fed for 151 d. In Exp. 2, 199 steers (430 ± 1.9 kg BW) were stratified by BW and allocated to 1 of 2 treatments consisting of 1) 0 mg/steer daily of monensin and 2) 400 mg/steer daily of monensin and fed for 128 d. For both experiments, there were 4 pen replicates per treatment. For Exp. 1 and Exp. 2, the model included the fixed effect of treatment for growth performance measures and the fixed effects of treatment, time, and treatment × time interaction, respectively, for O157:H7 shedding. In Exp. 1, final BW was 1.9% greater for heifers fed 400 mg/d monensin than for heifers fed 200 mg/d monensin ( = 0.05). Furthermore, ADG was 4.9% greater ( = 0.05) and G:F was 3.1% greater ( = 0.04) when the heifers were fed 400 mg/d monensin vs. 200 mg/d monensin. Pen prevalence for O157:H7 ( = 0.96) and the percentage of animals in the pen shedding O157:H7 at enumerable levels ( = 0.82) did not differ between heifers fed 200 mg/d monensin and heifers fed 400 mg/d monensin over the 4 sampling periods. For Exp. 2, steers fed the supplement containing monensin had a 1.9% greater final BW ( = 0.04) and a 5.2% greater ADG ( = 0.02) than steers fed a control supplement without monensin. No differences in DMI or G:F were noted across the treatments ( ≥ 0.14). O157:H7 percentage of enumerable cattle within the pen was greater for the steers fed monensin than the control steers not fed monensin than the control steers not fed monensin ( = 0.02) over the 4 sampling periods. However, the percentage of animals in the pen shedding O157:H7 (prevalence positive) did not differ between treatments ( = 0.18), nor did the average fecal counts ( = 0.45). In conclusion, feeding a higher dose (400 mg/d) of monensin improved final BW and ADG compared with a low dose of monensin or a no-monensin control in steers and heifers across multiple years. The percentage of animals shedding O157:H7 at enumerable levels was greater for steers fed the monensin supplement than for steers fed the control supplement, yet the presence of monensin, irrespective of the dose, did not affect the percentage of animals in the pen shedding O157:H7.

2-Arachidonoylglycerol as a possible treatment for anorexia nervosa in animal model in mice.

We have investigated the effects of 0.001mg/kg 2-arachidonoylglycerol (2-AG) administered in combination with compounds present in the body alongside 2-AG like 2-palmitoylglycerol and 2-linoleylglycerol (also termed "entourage"), on cognitive function,food intake, and neurotransmitter levels in the hippocampus and hypothalamus of mice under diet restriction. Young female Sabra mice were treated with vehicle, 2-AG, 2-AG+entourage, 2-AG+entourage+5-(4-Chlorophenyl)-1-(2,4-dichloro-phenyl)- 4-methyl-N-(piperidin-1-yl)-1H-pyrazole-3-carboxamide (SR141716A, a CB1 antagonist) and SR141716A. The mice were fed for 2.5h a day for 14days. Cognitive function was evaluated by the eight arm maze test, and neurotransmitter (norepinephrine, dopamine, L-DOPA and serotonin) levels were measured in the hippocampus and hypothalamus by high-performance liquid chromatography-electrochemical detection. Food intake was increased by 2-AG and, to an even greater extent, by 2-AG+entourage. SR141716A reversed the effect of 2-AG+entourage. The administration of 2-AG+entourage improved cognitive function compared to the vehicle mice, and this improvement was blocked by SR141716A. 2-AG+entourage-treated mice showed an increase in norepinephrine (NE), dopamine and L-DOPA levels in the hippocampus. SR141716A normalized NE and L-DOPA levels. There were no significant changes in hypothalamic neurotransmitter levels. The use of very low doses of the endocannabinoid 2-AG+entourage can improve cognitive function by elevating norepinephrine and L-DOPA levels in the hippocampus, without cannabinomimetic side effects. These findings may have implications for cognitive enhancement in anorexia nervosa.

The effect of lipoic acid and vitamin E therapies in individuals with the metabolic syndrome.

The metabolic syndrome is associated with abnormal glucose and lipid metabolism, insulin resistance, increased oxidative stress and pro-inflammatory activity that increase the risk of type 2 diabetes and cardiovascular disease. The aim of this study was to investigate the effect of treatment with the antioxidant α-lipoic acid (ALA) with or without vitamin E supplementation, on markers of insulin resistance and systemic inflammation and plasma nonesterified fatty acid (NEFA) concentrations in individuals with the metabolic syndrome. In a randomized, double-blind, placebo-controlled trial, subjects with the metabolic syndrome received ALA (600 mg/day, n = 34), vitamin E (100 IU/day, n = 36), both ALA and vitamin E (n = 41), or matching placebo (n = 40) for 1 year. Fasting circulating concentrations of glucose and insulin were measure every 3 months and NEFA, markers of inflammation, adiponectin and vitamin E were measured at 6 monthly intervals. Plasma NEFA concentrations decreased [-10 (-18, 0)%] at a marginal level of significance (p = 0.05) in those who received ALA alone compared with placebo and decreased [-8 (-14, -1)% (95% CI)] significantly (P = 0.02) in participants who were randomised to ALA with and without vitamin E compared with those who did not receive ALA. Fasting glucose, insulin, homeostatic model assessment of insulin resistance, adiponectin, and markers of inflammation did not change significantly during the study. These data suggest that prolonged treatment with ALA may modestly reduce plasma NEFA concentrations but does not alter insulin or glucose levels in individuals with the metabolic syndrome.

Effects of antimicrobials fed as dietary growth promoters on faecal shedding of Campylobacter, Salmonella and shiga-toxin producing Escherichia coli in swine.

AIMS: To determine whether antimicrobials commonly used in swine diets affect zoonotic pathogen shedding in faeces. METHODS AND RESULTS: Barrows (n = 160) were sorted into two treatments at 10 weeks of age (week 0 of the study), and fed growing, grow finishing and finishing diets in 4-week feeding periods. For each feeding phase, diets were prepared without (A-) and with (A+) dietary antimicrobials (chlortetracycline, 0-8 week; bacitracin, 9-12 week) typical of the United States. At week 0, 4, 8, 9, 10 and 12 of the study, faecal swabs or grabs were collected for analyses. Campylobacter spp. was absent at week 0, but prevalence increased over time with most isolates being identified as Campylobacter coli. When chlortetracycline was used in A+ diets (week 4 and 8), prevalence for Campylobacter spp., pathogenic Escherichia coli O26 and stx genes was lower in faeces. On week 12 after the shift to bacitracin, Campylobacter spp. and stx genes were higher in faeces from piglets fed A+ diet. Pathogenic E. coli serogroups O103 and O145 were isolated throughout the study and their prevalence did not differ due to diet. Pathogenic E. coli serogroups O111 and O121 were never found in the piglets, and Salmonella spp. prevalence was low. CONCLUSIONS: In production swine, growing diets with chlortetracycline may have reduced pathogen shedding compared with the A-growing diets, whereas finishing diets with bacitracin may have increased pathogen shedding compared with the A-finishing diet. SIGNIFICANCE AND IMPACT OF THE STUDY: Inclusion of antimicrobials in the diet can affect zoonotic pathogen shedding in faeces of swine.

Incorporation of thymol into corncob granules for reduction of odor and pathogens in feedlot cattle waste.

Confined animal feeding operations can be a source of odor emissions, global warming gases, water pollution, and food contamination. Laboratory studies have indicated that plant oils with antimicrobial activity can be used to control pathogens and odor emissions from cattle and swine wastes. However, these oils are aromatic and may volatilize when applied topically. Our objectives were to evaluate the volatility of thymol from a feedlot surface and the effectiveness of topically applying thyme oil (2.5% thymol), incorporated into corncob granules and added once per week, to control odor emissions and total coliforms in feedlot manure. In the first study, thymol either volatilized or was degraded within 28 d after topical application. In a second study, thyme oil (2.5% thymol) was incorporated into corncobs and applied to pen surfaces weekly. Manure samples from 6 locations in each pen were collected from 3 untreated and 3 thymol-corncob-treated pens (15 x 150 m; fifty 400-kg cattle/pen), 3 times per week for 8 wk. Samples were analyzed for thymol concentration, total VFA, branched-chain VFA, aromatic compounds, and the number of Escherichia coli and total coliform bacteria. Over the 8 wk, with the exception of wk 7, the desired thymol concentration of 15 to 20 micromol/g DM was maintained in the manure. Concentrations of VFA and branched chain-VFA increased over time in untreated and treated pens. However, the rate of VFA accumulation in treated pens (7.5 +/- 1.3 micromol.g DM(-1).wk(-1)) was less (P < 0.01) than the rate of accumulation in untreated pens (18.0 +/- 2.1 micromol.g DM(-1).wk(-1)). Likewise, the rate of branched-chain VFA accumulation in treated pens (0.31 +/- 0.04 micromol.g DM(-1).wk(-1)) was less (P < 0.01) than in untreated pens (0.55 +/- 0.06 micromol.g DM(-1).wk(1)). The concentrations of E. coli in treated pens (2.9 +/- 1.2 x 10(5) cfu.g DM(-1)) were 91% less (P < 0.04) than in untreated pens (31.1 +/- 4.0 x 10(5) cfu.g DM(-1)). Similarly, concentrations of coliforms in treated pens (3.7 +/- 1.3 x 10(5) cfu.g DM(-1)) were 89% less (P < 0.04) than those of untreated pens (35.3 +/- 4.2 x 10(5) cfu.g DM(-1)). These results indicate that odor emissions and total coliforms can be reduced in feedlot manure with a once per week application of thymol incorporated in a granular form. However, corncobs are bulky, and other granular carriers with a greater carrying capacity for thyme oil should be explored.

Recommended micronutrient supplementation for institutionalized elderly.

A committee nominated by the Israel Ministry of Health examined the relevant literature and the local recommendations as well as the recommendations from other countries and suggested a daily micronutrient supplementation for institutionalized elderly living in institutions supervised by the Ministry of Health. The micronutrient preparatory, tailored for this population, is designed to contain about half the RDA for most of the vitamins and some microelements. Biotin and vitamins C, D and B12 as well as zinc, copper, chromium and molybdenum are suggested at a level higher than half the RDA, whereas fluorine, at a lower level. Major elements (calcium, magnesium and phosphorus) are excluded and should be supplied separately. Vitamin K and iron are also excluded. Fat-soluble vitamins should be microencapsulated. Micronutrient supplementation for institutionalized elderly is part of the Ministry of Health s balanced nutrition policy. The committee s recommendations are also applicable to the free-living elderly population.

Wheat grass juice in the treatment of active distal ulcerative colitis: a randomized double-blind placebo-controlled trial.

BACKGROUND: The use of wheat grass (Triticum aestivum) juice for treatment of various gastrointestinal and other conditions had been suggested by its proponents for more than 30 years, but was never clinically assessed in a controlled trial. A preliminary unpublished pilot study suggested efficacy of wheat grass juice in the treatment of ulcerative colitis (UC). METHODS: A randomized, double-blind, placebo-controlled study. One gastroenterology unit in a tertiary hospital and three study coordinating centers in three major cities in Israel. Twenty-three patients diagnosed clinically and sigmoidoscopically with active distal UC were randomly allocated to receive either 100 cc of wheat grass juice, or a matching placebo, daily for 1 month. Efficacy of treatment was assessed by a 4-fold disease activity index that included rectal bleeding and number of bowel movements as determined from patient diary records, a sigmoidoscopic evaluation, and global assessment by a physician. RESULTS: Twenty-one patients completed the study, and full information was available on 19 of them. Treatment with wheat grass juice was associated with significant reductions in the overall disease activity index (P=0.031) and in the severity of rectal bleeding (P = 0.025). No serious side effects were found. Fresh extract of wheat grass demonstrated a prominent tracing in cyclic voltammetry methodology, presumably corresponding to four groups of compounds that exhibit anti-oxidative properties. CONCLUSION: Wheat grass juice appeared effective and safe as a single or adjuvant treatment of active distal UC.

[Micronutrient (vitamins and minerals) supplementation for the elderly, suggested by a special committee nominated by Ministry of Health].

The elderly tend to be at a higher risk for nutritional deficiencies and in particular for micronutrient deficiencies. A committee nominated by Ministry of Health examined the relevant literature and the local recommendations as well as the recommendations from other countries and suggested a daily special micronutrient supplementation for institutionalized elderly. The preparatory will contain about half the RDA for most of the micronutrients, except for fluorine that is recommended at a lower level and biotin, vitamins D, C, B12 as well as zinc, copper and molybdenum at a level higher than half the RDA. Major elements such as calcium, are not included in the preparatory and would be supplied separately when needed. Vitamin K and iron are excluded as well. The suggested preparatory composition, mg: vitamin A, 0.450; vitamin D, 0.015; vitamin E, 10; thiamin, 0.6 Pound riboflavin, 0.7; biotin, 0.030; pantothenic acid, 3; niacin, 8; vitamin C, 60; vitamin B6, 0.8; folic acid, 0.120; vitamin B12, 0.0024; choline up to 275; zinc, 8; copper, 0.9; fluorine, 0.5; manganese, 1.2; chromium 0.020; molybdenum, 0.045; selenium, 0.030; and iodine, 0.075. Fat-soluble vitamins should be microencapsulated. Micronutrient supplementation is part of Ministry of Health balanced nutrition policy. The committees recommendations are also applicable for the free-living elderly.

Low dose anandamide affects food intake, cognitive function, neurotransmitter and corticosterone levels in diet-restricted mice.

This investigation reports the possible role of the endocannabinoid anandamide on modulating the behavioral and neurochemical consequences of semi-starvation. We studied the effect of very low dose anandamide (0.001 mg/kg) administration on food intake, cognitive function and catecholaminergic and serotonergic pathways in two murine brain areas concerned with appetite (hypothalamus) and learning (hippocampus), and the peripheral corticosterone response to the stress of 40% diet restriction. Anandamide-treated mice consumed 44% more food (P<0.05) during 1 week of 2.5-h feeding each day. In the hypothalamus, there were significantly increased concentrations of norepinephrine (P<0.01), dopamine (P<0.05) and 5-hydroxytryptamine (5-HT) (P<0.001). In the hippocampus, anandamide increased significantly norepinephrine and dopamine, but decreased 5-HT (all at P<0.001). Diet restriction was accompanied in both areas by a significant decrease in all neurotransmitter concentrations that were partially restored by anandamide for dopamine and 5-HT, but not for norepinephrine. In animals on diet restriction, anandamide significantly improved impaired maze performance. Norepinephrine turnover and plasma corticosterone levels were also raised significantly by anandamide. The fact that low dose anandamide improved food intake, cognitive function and reversed some of the neurotransmitter changes caused by diet restriction, might have implications for the treatment of cachexia associated with acquired immunodeficiency syndrome (AIDS) and cancer, for mood changes sometimes associated with dieting, and in the extreme case, of patients with anorexia.

A balanced 5:1 carbohydrate:protein diet: a new method for supplementing protein to patients with chronic liver disease.

BACKGROUND AND AIMS: Protein malnutrition in patients with chronic liver disease contributes to bone and muscle weakness and compromises immune function and survival. In contrast, high-protein diets may induce or exacerbate hepatic encephalopathy. The aim of the present study was to test whether increased amounts of protein, balanced by dietary carbohydrate in a 1:5 ratio, may be given to chronic liver disease patients in order to minimize postprandial increases in plasma amino acid (AA) concentrations. METHODS: Eight patients with chronic liver disease were studied. Each received, in a randomized order, three different diets of 2510 kJ of either high protein (37:50:28, carbohydrate:protein:fat), high carbohydrate (126:10:6) or a balanced 5:1 carbohydrate:protein diet (105:21:11). All patients were followed for plasma AA, glucose and insulin levels, as well as for cognitive and behavioral changes. RESULTS: Following the high protein diet, AA concentrations were significantly increased. In contrast, after the balanced diet, AA levels were practically constant enabled. All diets was well tolerated and no cognitive or behavioral changes appeared. CONCLUSION: The administration of a balanced 5:1 carbohydrate:protein diet may enable patients with chronic liver disease to tolerate increased amounts of dietary protein, without altering plasma amino acid concentrations.

The effect of fish oil on hypertension, plasma lipids and hemostasis in hypertensive, obese, dyslipidemic patients with and without diabetes mellitus.

We have recently reported that dietary fish oil supplementation (n-3) polyunsaturated fatty acid (PUFA) led to a reduction in blood pressure (BP) and serum triglycerides (TG), in addition to the normalization of the hypercoagulable state in subjects with obesity, hypertension and dyslipidemia without diabetes mellitus (OHD-DM). The aim of the present study was to explore the mechanism of this amelioration by comparing the previous results to those obtained from 19 subjects who, in addition to the conditions described above, also suffer from diabetes mellitus (OHD+DM) and proteinuria. In both the non-diabetic and diabetic groups, a similar reduction was observed in BP (from 158.7/80.8 to 146/72.9 mmHg, and from 157.6/83.2 to 141.9/75.6 mmHg, respectively, P<0.001) and TG levels (from 159.2 to 108.0 mg/dl and from 208.7 to 153.1 mg/dl, respectively, P<0.001). However, a favorable reduction in hemostasis parameters (platelet aggregation on extracellular matrix and (alpha2-antiplasmin) was only seen among the nondiabetic patients (from 12.1+/-4.9 to 4.2+/-3.2%, P<0.001). This difference may stem from a less efficient exchange between n-3 and n-6 PUFA in serum phospholipid of the OHD+DM patients. Overall, this 13-day fasting/refeeding method developed by us has proven to cause the rapid exchange of arachidonic acid for eicosapentaenoic acid. It appears to be an effective regimen for the reduction of cardiovascular risk factors (BP, TG and hemostatic variables) in OHD-DM patients and to a lesser extent in OHD+DM patients.

Citrus fruit supplementation reduces lipoprotein oxidation in young men ingesting a diet high in saturated fat: presumptive evidence for an interaction between vitamins C and E in vivo.

To determine the effects of vitamin C on cardiovascular risk factors, we studied dietary vitamin C enrichment in 36 healthy male students consuming a diet high in saturated fatty acids. After a 1-mo run-in period during which the subjects consumed approximately 50 mg ascorbic acid/d (low-C diet), half of the subjects were randomly assigned to receive 500 mg ascorbic acid/d for an additional 2 mo (high-C diet). Plasma ascorbic acid increased from 13.5 micromol/L with the low-C diet to 51.7 micromol/L with the high-C diet. Plasma cholesterol increased slightly with the high-C diet, but not above baseline concentrations. This increase was offset by an increase in the lag period of in vitro LDL oxidation, which correlated with plasma ascorbic acid concentrations (r = 0.735, P = 0.0012). Lipoprotein vitamin E concentrations were unchanged with the two diets. There were no effects on concentrations of fibrinogen or factor VII. The fact that ascorbic acid reduced the in vitro susceptibility of lipoproteins to oxidation provides presumptive evidence for an interaction between aqueous and lipophilic antioxidants (vitamins C and E ) in maintaining the integrity of LDL particles.

Dietary fatty acids in the management of diabetes mellitus.

Dietary fatty acid recommendations for patients with diabetes mellitus may be neither similar to, nor extrapolated from, those for the normal population; some evidence suggests that diabetes prevalence may be correlated with the dietary ratio of n-6 to n-3 fatty acids. In human experiments, n-3 fatty acids may improve many of the metabolic sequelae of insulin resistance by lowering blood pressure and triacylglycerol concentrations. In animals, n-3 fatty acids may cause less weight gain than other fats; however, they may raise low-density-lipoprotein concentrations, increase hepatic glucose output, and decrease insulin secretion in non-insulin-dependent diabetes mellitus. In a minority of patients with insulin-dependent diabetes mellitus, glycemic control may be adversely affected n-6 Fatty acids lower plasma cholesterol but may increase lipoprotein oxidation. Glucose in the presence of transition metals may produce free radicals and result in pancreatic damage and the formation of glycosylation products that inhibit nitric oxide-mediated smooth muscle relaxation; fish oil may counter these effects. High-carbohydrate, low-fat diets, once recommended for diabetes mellitus, appear to aggravate hypertriglyceridemia and are inferior to diets high in monounsaturated fatty acids (MUFAs) if saturated fats are kept to a minimum. MUFA-rich diets improve lipid profiles and may also have antioxidant properties. However, high-fat diets-whatever their composition-promote obesity. Current advice individualizes carbohydrate and fat requirements to optimize blood glucose and lipid concentrations in a lifestyle program to control obesity, exercise, smoking, and blood pressure. Fatty acid modifications may fine-tune the diet if proper balance is kept between the different long-chain polyunsaturated fatty acids and antioxidant requirements.

Pentoxifylline and thalidomide fail to reduce hepatic steatosis during total parenteral nutrition and bowel rest in the rat.

BACKGROUND: We suggested that the continuous translocation of endotoxin from Gram-negative bacterial overgrowth during bowel rest and total parenteral nutrition (TPN) causes the release of tumor necrosis factor (TNF), resulting in liver damage and hepatic dysfunction. Because TPN-induced hepatic steatosis was significantly reduced by the monoclonal antibodies against TNF, we attempted a more clinically applicable approach using pentoxifylline and thalidomide. METHODS: A control group (group I) fed rat chow and four groups of rats receiving TPN were studied. Group II received TPN only; group III, TPN and 100 mg/kg/d pentoxifylline; group IV, TPN and 200 mg/kg/d pentoxifylline; and group V, TPN and 5 mg/kg/d thalidomide. On day 7, total liver fat was determined. RESULTS: Bowel rest and TPN resulted in a significant (p < .0005) increase in liver fat content that was unaltered by either pentoxifylline or thalidomide. CONCLUSIONS: Our results show no role for pentoxifylline or thalidomide in reducing TPN-associated hepatic steatosis.

Bond strength of composite to air-abraded enamel and dentin.

Human enamel and dentin were prepared with an air abrasion unit (KCP-2000), using two particle sizes (27 micrometers and 50 micrometers) of aluminum oxide. In vitro tensile bond strengths of a composite resin were determined after three enamel and three dentin surface treatments. Enamel treatments were: air abraded only, E-1; air abraded + adhesive, E-2; air abraded + acid etch + adhesive, E-3. Dentin surface treatments were air abraded only, D-1; air abraded + adhesive/no primer, D-2; air abraded + primer + adhesive, D-3. Etched enamel and dentin prepared with 600-grit SiC paper and adhesive served as controls. There were 10 replications for each condition. A dentin bonding system (Optibond) and a composite resin (Herculite XRV) were bonded to treated surfaces by light curing in an inverted, truncated cone die with a bond diameter of 3 mm. Samples were stored at 37 degrees C and 100% relative humidity for 24 hours and debonded in tension using a Universal Testing Machine at a 0.05 cm/min crosshead speed. Based on analysis of variance, there was no statistical difference between 27 micrometers and 50 micrometers aluminum oxide abrasive for both enamel and dentin. For enamel bond strengths, E-2 was significantly higher than E-1, and E-3 was significantly higher than E-1 and E-2. E-1 and E-2 were significantly lower than the control, while E-3 was not significantly different from the control (P < or = 0.05). For dentin bond strengths, D-2 was significantly higher than D-1, and D-3 was significantly higher than D-1 and D-2. All treatments except D-3 were significantly lower than the control (P < or = 0.05). Air-abrasion treatment of enamel and dentin alone resulted in reduced in vitro bond strengths as compared to etched enamel and dentin prepared with dentin adhesive and dentin primer.

Hyperphosphatemia: an objective marker for bulimia nervosa?

Phosphorus abnormalities among patients suffering from eating disorders, although cited, have received relatively little attention. Studies generally report decreased concentrations of phosphorus for both bulimia and anorexia nervosa. We have recently noted hyperphosphatemia in several consecutive hospitalized bulimic patients who appeared to have normal renal function and calcium levels. Case files of 30 inpatient and outpatient female bulimic patients and 30 sex- and age-matched physically healthy psychiatric inpatients and outpatients were reviewed. Phosphorus and electrolytes related to phosphorus metabolism were compared between the two groups. Twenty-four of 30 bulimic patients (80%) were found to have at least one elevated serum phosphorus concentration, whereas all but one of 30 age-matched controls had values within normal limits. Elevated phosphorus levels were generally in the mild to moderate range. No correlation was found between phosphorus levels and any of the other electrolytes examined in both patients and controls. No correlation was found between phosphorus levels and the reported frequency of bingeing and vomiting or the number of laxatives ingested. Since bulimic patients are generally of normal weight and tend to deny their disturbed eating habits, diagnosis is often delayed. However, bulimia may be suspected from biochemical abnormalities such as hypokalemia, hypochloremia, elevated amylase, and acid-base disturbances. This preliminary study indicates that elevated serum phosphorus levels may serve as an additional objective marker for the presence of bulimia nervosa.

Antitumor necrosis factor antibodies reduce hepatic steatosis during total parenteral nutrition and bowel rest in the rat.

BACKGROUND: In previous studies, we demonstrated the overgrowth of gram-negative bacteria in the gut and an enhanced release of tumor necrosis factor (TNF) by peritoneal macrophages, suggesting that endotoxin, TNF, or both, may act as hepatotoxins to produce hepatic steatosis during total parenteral nutrition (TPN) and bowel rest. The present study attempts to better define the role of each of these two mediators. The first part examines the LD50 for various doses of endotoxin in TPN-treated rats compared with free-feeding and free-feeding saline-infused rats. In the second part we repeatedly administered anti-TNF monoclonal antibodies to rats subjected to TPN and bowel rest. METHODS: In the first set of experiments, 87 male Sabra rats were randomized into three groups: free-feeding, infused with normal saline, and infused with TPN. On day 7 of the experiment, all rats received an IV injection of endotoxin at various doses (1.5, 2.5, 5.0, 7.5, and 10 mg/kg). The LD50 in the three groups and at the various doses of lipopolysaccharide tested was determined at 24 hours postinjection. In the second set of experiments, 38 male Sabra rats were randomized into three groups: infused with normal saline and fed rat food ad libitum, infused with TPN, and infused with TPN but also receiving monoclonal antibodies against TNF. RESULTS: Lower endotoxin doses were required to achieve LD50 in the two IV-infused groups (2.5 to 5.0 mg/kg) compared with the free-feeding group (7.5 mg/kg) (p < .03). These findings suggest a moderate increase in susceptibility to the lethal effect of endotoxin in IV-treated rats. The total hepatic fat and triglyceride levels, which were markedly increased in TPN rats, were significantly reduced by using anti-TNF antibodies. Enhanced TNF production by peritoneal macrophages during TPN was completely eliminated by anti-TNF antibodies, probably the result of suppressed TNF production. CONCLUSIONS: The continuous translocation of endotoxin from gram-negative bacterial overgrowth in the gut during TPN and bowel rest results in enhanced release of TNF by macrophages. TNF causes hepatic dysfunction, portrayed in the present experimental model as hepatic steatosis. TPN-induced hepatic steatosis was significantly reduced by the administration of monoclonal antibodies against TNF-alpha.

The effect of quinidine and myocardial ischemia on the isolated rat heart with fat-free diet.

Fat-free diet changes the lipid content and the electrophysiological properties of the rat myocardium. Five percent fat supplementation to the diet does not alter the basic electrophysiological properties but still has a biochemical effect on the lipid content of the myocardium. The purpose of this work was to determine whether these biochemical alterations affect the response of the myocardium to quinidine and ischemia, both of which interact with the lipid component of the membrane. We used strength-duration, strength-interval and threshold of ventricular fibrillation to measure the electrophysiological properties of the isolated rat heart at baseline and after 30 minutes of quinidine perfusion or coronary artery ligation. The fatty acid composition of the myocardium was analyzed. We found that a fat-free diet caused essential fatty-acid deficiency, while 5% fat supplementation had a partial protective effect. Quinidine decreased excitability and increased refractoriness in both groups but had more effect on the fat-free diet hearts group. There was no difference in the ventricular fibrillation threshold. Ischemia increased myocardial excitability in the fat-free diet hearts group and had no effect on refractoriness or ventricular fibrillation threshold. These results support the theory that the lipid composition of the myocardial membrane affects its response to lipophilic drugs and ischemia.