Fat-free Meal Research Articles

Effect of High Linoleic Acid Diet on Carbohydrate‐stimulated Expression of Lipogenic Genes

Linoleic acid, an ω‐6 PUFA, has been proposed to inhibit de novo lipogenesis (DNL) by decreasing expression of SREBP‐1c, a major regulator of DNL. To investigate whether previous intake of a high linoleic acid diet inhibits carbohydrate‐stimulated SREBP‐1c expression and DNL in vivo, we compared the expression of SREBP‐1c and its lipogenic targets in the fasted and post‐meal states in male Sprague‐Dawley rats fed: 1) a 55% fat (78% linoleic acid) diet (n=15, P); 2) a 55% fat (linoleic acid‐free) diet (n=15, S); or 3) a no‐fat diet (n=15, N) for 1 wk. All rats were fasted for 24 h; liver samples were obtained at fasting, 16h after refeeding on a 74% carbohydrate, fat‐free meal, or 45 min after injection with insulin + glucose.
 Body weights and liver lipid levels were greater in P and S than N rats (P=S>N; p< .01) but % body fat was higher in P than S rats (P>S=N, p< .01). Refeeding increased mRNA for SREBP‐1c and the lipogenic enzymes Acetyl CoA Carboxylase, Steroyl CoA Desaturase 1, and Pyruvate Kinase compared with fasting in all groups similarly, but expression of Fatty Acid Synthase was lower in the P vs. S group (p< .02). In all groups, refeeding or insulin decreased Phosphoenolpyruvate Carboxykinase mRNA and increased Glucokinase mRNA, indicating normal insulin sensitivity. Refeeding decreased expression of INSIG2, a protein which inhibits maturation of SREBP‐1c, in the S and N groups (p< .002), but not the P group.The minimal reduction in the stimulation of lipogenic gene expression seen in the high‐linoleic acid group was not associated with decreased expression SREBP‐1c, but was associated with lack of suppression of INSIG2 expression, suggesting that ω‐6 PUFA may impair processing rather than expression of SREBP‐1c.

Nightly dosing of regorafenib.

549 Background: Fatigue and anorexia are major side effects in the use of regorafenib. These effects are compounded in patients with metastatic colon cancer to the liver. Finding a good fit for this agent has been difficult in patients when used in third and fourth line treatments. Our clinic has treated 21 patients with this agent. Methods: After the first four patients’s experienced extreme fatigue and anorexia at the recommended starting dose of 160mg daily, it was decided to start at a 21 day dose of 120mg. Even at this starting dose, it was necessary to dose deescalate. Ten patients were treated at the 120 mg daily dose and escalated 160 mg daily if tolerated. The agent was given at night to take advantage of the sleep period and the diurnal variation in adrenal gland function. No patient was treated with oral corticosteroids. Results: Two patients previously treated and responders were retreated after they decided they would give the agent a second opportunity. One of these patients, on day two of receiving the agent, developed a severe rash and the treatment was stopped. One patient received the agent for one week before he decided to stop, but was experiencing no side effects. Eight patients were eligible for evaluation. All patients had metastatic disease to the liver. Six were treated for at least two months and two were treated only for one month. All therapy was discontinued because of progression of disease. Fatigue and anorexia were evaluated by a change in their ECOG performance status, fatigue criteria and weight change. ECOG performance status of the patients was, ECOG 1, one patient, ECOG 2, six patients, ECOG 3, one patient. The evaluation was done before, during and after each monthly treatment. No patient had a greater than 5% weight loss. Four patients had Grade 1 fatigue, (fatigue relieved by resting). Six of the eight patients were escalated to 160mg daily after two weeks. Conclusions: Although this is a small sample study, it appears that night time dosing may be effective in helping a patient to achieve maximum benefit of regorafenib therapy. This study did not address the changes in absorption caused by a light fat free meal taken at night, and does not take into consideration the possible change in half-life of the agent when taken at night.

Dietary Fat Increases Vitamin D-3 Absorption

BackgroundThe plasma 25-hydroxyvitamin D response to supplementation with vitamin D varies widely, but vitamin D absorption differences based on diet composition is poorly understood. ObjectivesWe tested the hypotheses that absorption of vitamin D-3 is greater when the supplement is taken with a meal containing fat than with a fat-free meal and that absorption is greater when the fat in the meal has a higher monounsaturated-to-polyunsaturated fatty acid ratio (MUFA:PUFA). DesignOpen, three-group, single-dose vitamin D-3 comparative absorption experiment. Participants/settingOur 1-day study was conducted in 50 healthy older men and women who were randomly assigned to one of three meal groups: fat-free meal, and a meal with 30% of calories as fat with a low (1:4) and one with a high (4:1) MUFA:PUFA. After a 12-hour fast, all subjects took a single 50,000 IU vitamin D-3 supplement with their test breakfast meal. Main outcome measuresPlasma vitamin D-3 was measured by liquid chromatography–mass spectrometry before and 10, 12 (the expected peak), and 14 hours after the dose. Statistical analyses performedMeans were compared with two-tailed t tests for independent samples. Group differences in vitamin D-3 absorption across the measurement time points were examined by analysis of variance with the repeated measures subcommand of the general linear models procedure. ResultsThe mean peak (12-hour) plasma vitamin D-3 level after the dose was 32% (95% CI 11% to 52%) greater in subjects consuming fat-containing compared with fat-free meals (P=0.003). Absorption did not differ significantly at any time point in the high and low MUFA and PUFA groups. ConclusionsThe presence of fat in a meal with which a vitamin D-3 supplement is taken significantly enhances absorption of the supplement, but the MUFA:PUFA of the fat in that meal does not influence its absorption.

Studies on Lipid Profiles and Fatty Acid Composition of Roe from Rohu (Labeo rohita) and Murrel (Channa striatus)

The lipid profiles and fatty acid composition of roes from two common fresh water fish viz., rohu (Labeo rohita) and murrel (Channa striatus) have been studied. The dehydrated fish egg was ground to fine powder and extracted with chloroform/methanol (2:1, v/v) to recover the total lipid in 20.2 and 22.7% on dry weight basis. The fat free meal was found to contain 70 and 58% protein in rohu and murrel, respectively. The total lipids were separated into neutral lipids, glycolipids and phospholipids using silica gel column chromatography and found to be 43.8, 72.9% neutral lipids; 12.7, 9.4% glycolipids and 43.5, 17.7% phospholipids in rohu and murrel roes, respectively. The fatty acid compositions of all lipid classes were analysed by GC and GC-MS. Among the saturated fatty acids, hexadecanoic acid (16:0) was found to be 30.2 and 30.4% respectively in rohu and murrel total lipid. n-3 Fatty acids namely eicosapentaenoic acid (20:5, EPA) was observed to an extent of 1.5 and 0.6% and docosahexaenoic acid (22:6, DHA) to an extent of 11.8 and 6.1% respectively in rohu and murrel total lipids. Stearic acid (18:0) was also seen at 12.2 and 6% respectively in rohu and murrel lipids. The fatty acid composition was found to be almost similar in all the lipid classes. The study indicated that rohu and murrel fish egg lipids are good sources for polyunsaturated n-3 fatty acids.

Role of Free Fatty Acids in Regulating Gastric Emptying and Gallbladder Contraction

The limited effectiveness of orlistat, an inhibitor of gastrointestinal lipases, in inhibiting fat digestion is not completely understood. Therefore we studied the effect of orally and duodenally administered orlistat on gastric emptying, cholecystokinin (CCK) secretion, and gallbladder contraction. In healthy males, gastric emptying of solids and fat were quantified scintigraphically, gallbladder contraction by ultrasound and CCK release by radioimmunoassay. Three studies were performed: (1) oral and (2) duodenal orlistat with a fat-containing meal, and (3) duodenal orlistat with a fat-free meal. Gastric emptying rates of solids and fat (T_50% accelerated by 16 and by 22%, p< 0.05, respectively) were significantly faster after duodenal perfusion of orlistat; gallbladder contraction and CCK release were reduced under these conditions (p < 0.005, respectively). With oral orlistat no significant effect was documented on these parameters. We conclude that fat hydrolysis is essential in the regulation of fat-induced gastric emptying and gallbladder contraction.

A randomised cross-over trial in healthy adults indicating improved absorption of omega-3 fatty acids by pre-emulsification

BackgroundThe health benefits of increased intakes of omega-3 fatty acids are well established but palatability often presents a problem. The process of emulsification is used in the food industry to provide a wider spectrum of use, often with the result of increased consumption. Moreover, as emulsification is an important step in the digestion and absorption of fats, the pre-emulsification process may enhance digestion and absorption. In this study the levels of plasma fatty acid and triacylglycerol (TAG) following the ingestion of either an oil mixture or an emulsified oil mixture have been compared.MethodsIn this randomised cross-over study, 13 volunteers received the oil mixture and 11 received the oil emulsion as part of an otherwise fat free meal. Blood samples were collected at 0, 1.5, 3, 4.5, 6, 7.5 and 9 hours after ingestion of oil, separated and stored at -20°C. Plasma triacylglycerols were assessed spectrophotometrically and fatty acids were determined by gas chromatography. Following a washout period of twenty days the procedure was repeated with the assignments reversed.ResultsThe postprandial plasma TAG and the C18:3 (n-6), C18:3(n-3), C20:5(n-3) and C22:6 (n-3) polyunsaturated fatty acid (PUFA) levels for the emulsified oil group were increased significantly (P = 0.0182; P = 0.0493; P = 0.0137; P < 0.0001; P = 0.0355 respectively) compared with the non-emulsified oil group. The C16:0 and C18:0 saturated fatty acids, the C18:1 (n-9) monounsaturated fatty acid and the C18:2 PUFA were not significantly different for the oil and emulsified oil groups.ConclusionPre-emulsification of an oil mixture prior to ingestion increases the absorption of longer chain more highly unsaturated fatty acids (especially eicosapentaenoic acid and docosahexaenoic acid) but does not affect absorption of shorter chain less saturated fatty acids, suggesting that pre-emulsification of fish oils may be a useful means of boosting absorption of these beneficial fatty acids. Trial registration: Current Controlled Trials ISRCTN43202606

Polyunsaturated fatty acids acutely suppress antibodies to malondialdehyde-modified lipoproteins in patients with vascular disease

Antibodies to malondialdehyde (MDA)-modified low-density lipoprotein (LDL) are transiently reduced during the postprandial period in patients with atherosclerotic heart disease. Previous experiments using mixed meals high in fat have found reductions of approximately 20% within 2 hours. This study was designed to reveal if this phenomenon was due uniquely to saturated fats. Using a standardized immunoassay for the detection of circulating levels of autoantibodies (AAbs) against MDA-modified LDL, we examined the acute changes in AAb levels during 6 hours of postprandial lipemia in 10 men with known atherosclerotic heart disease. Each subject was given 4 meals 1 week apart. Three of the meals differed in content of saturated fat, monounsaturated fat, and polyunsaturated fat. A fat-free meal with equivalent carbohydrate and equivalent protein was also administered. The study was double blinded and the meals were administered in random order. Only the meal enriched with polyunsaturated fatty acids caused the reduction in antibodies to MDA-LDL. This decrease was statistically significant from baseline at 1 hour (p <0.05), 2 hours (p <0.004), and 3 hours (p <0.02), with the nadir occurring at 2 hours. Polyunsaturated fatty acids are the major stimulus for causing a reduction in the AAbs to MDA-LDL during postprandial lipemia. These results strongly suggest that fat in chylomicrons may be a major source of oxidized lipids in the blood of patients with arteriosclerosis.

Amounts and types of fatty acids in meals affect the pattern of retinoids secreted in human chylomicrons after a high-dose preformed vitamin A intake

High doses of preformed vitamin A are commonly used to correct vitamin A deficiency. Newly absorbed vitamin A is secreted mainly as retinyl esters in chylomicrons. The effect of changing types and amounts of fatty acids on fatty acid composition of chylomicron retinoid esters when a high dose of vitamin A is ingested have not been studied previously. In the present study, 10 healthy young men ingested, in a random order, mixed meals containing 15,000 retinol equivalents (RE) of vitamin A (as retinyl palmitate) and either no fat or 40 g of fat provided as butter, olive oil, or sunflower oil. Fasting and postprandial blood samples were obtained for 7 hours after meals. Free retinol and the main retinyl esters (retinyl palmitate/oleate, stearate, and linoleate) were measured in chylomicrons by high-performance liquid chromatography (HPLC). Chylomicron retinyl palmitate/oleate and retinyl stearate concentrations significantly increased after intake of the 4 test meals. Conversely, chylomicron retinyl linoleate and chylomicron free retinol significantly increased only after the sunflower and the fat-free meals, respectively. The main retinoid secreted in chylomicrons after the intake of the fat-rich meals was retinyl palmitate/oleate, accounting for 63% to 79% of total RE, but it was free retinol after the fat-free meal (51% of total RE). Thus, the retinoid pattern secreted in chylomicrons after the intake of a high dose of preformed vitamin A depends on type and amounts of fatty acids ingested. To explain this result we suggest that the esterification process of retinol in the enterocyte by lecithin:retinol acyltransferase can be overwhelmed by a high load of vitamin A. Consequently, a significant proportion of the retinol is esterified by acyl coenzyme A:retinol acyltransferase (ARAT) with ingested fatty acids, explaining the appearance of retinyl linoleate in chylomicrons after the sunflower oil meal. If a high dose of preformed vitamin A is ingested with a fat-free meal, a significant proportion of retinol is not esterified, owing to the lack of fatty acids for ARAT, which explains the appearance of free retinol in chylomicrons. Copyright 2003 Elsevier, Inc. All rights reserved.

Chylomicron fatty acid composition and serum lipid concentrations in subjects fed carpenin or palm oil/palm kernel oil as the major dietary fat

This study, part of a larger study of dietary fats with different saturated fatty acid content, was performed to investigate the effect of caprenin on chylomicron fatty acid composition and postprandial serum lipid concentrations. Caprenin is a triglyceride made of caprylic acid (8:0), capric acid (10:0) and behenic acid (22:0). Thirty subjects were standardized for 3 weeks on a diet providing palm oil/palm kernel oil ( PO PKO ) as the major fat in a 38 energy % fat diet. Then, 15 subjects continued eating PO PKO while 15 switched to caprenin. After 5 weeks subjects consumed a meal with 40 g of test fat; blood was sampled at 0, 2, 4 and 6 hours. Amounts of 22:0 but not 8:0 and 10:0 varied (P<0.05 for time effect) over the 6 hour period in caprenin subjects; proportions of these fatty acids were much lower in chylomicrons than in the caprenin meal while proportions of palmitic acid (16:0) and oleic acid (18:1) were at least 4-fold higher in chylomicron lipids than in the meal. Postprandial concentrations of triglycerides in chylomicrons and serum and of cholesterol in plasma did not differ between dietary groups. These findings indicate 1) very low uptake of 8:0, 10:0 and 22:0 into chylomicrons, 2) a postprandial lipemia after caprenin comparable to that produced by other dietary fats as opposed to a fat-free meal, 3) considerable contribution of endogenously-derived fatty acids to chylomicron lipids and 4) equal effects of saturated fatty acids on pre- and postprandial concentrations of plasma cholesterol.

The effects of saturated fat and n-6 polyunsaturated fat on postprandial lipemia and hemostatic activity

The effect of different fat loads on postprandial lipemia and hemostatic activity was examined in 10 middle-aged men using 3 different meals. One meal was rich in saturated fatty acids (cream), the other rich in n-6 polyunsaturated fatty acids (sunflower oil) and the third was fat-free containing only carbohydrates. Lipoprotein lipids and hemostatic parameters were measured during fasting and 2, 4, 6 and 8 h after the test meal. In fasting samples, several hemostatic parameters were significantly associated with lipoprotein lipids. Most notable were the strong associations of fibrinolysis parameters tissue plasminogen activator antigen and plasminogen activator inhibitor activity (PAI-1) with total and very low density lipoprotein (VLDL) triglycerides. During lipemia, the associations were approximately similar or slightly weaker than in the fasting state. Both fat loads resulted in similar postprandial lipid responses: VLDL and high density lipoprotein (HDL) triglycerides reached maximum at 4 h after the meal. VLDL cholesterol also increased 4 and 6 h after the fat loads. HDL 3 cholesterol declined after the fatty meals but no change was observed in the HDL 2 fraction. The fat-free meal gave no significant lipid changes during the time course studied. Factor VII activity (F VII;C increased 6 and 8 h after the fatty meals, whereas a decrease was observed after the fat-free meal. The changes (± S.D.) at 8 h after cream, sunflower oil and fat-free meal were 5.2 ± 3.3, 3.3 ± 4.2 and -5.8 ± 7.9 percentage points, respectively, and the effect of the meal on the changes was statistically significant (F (8,99) = 2.99, P = 0.0048). F VII antigen (F VII:Ag) tended to decline during the day but there was no difference between the meals. Factor VIII activity (F VIII:C) was highest after the polyunsaturated fat meal and lowest after the fat-free meal. PAI-1 declined during the day and the decline tended to be steepest after the fat-free morning meal. The effect of the meal on the changes in lipoprotein lipids and hemostatic factors varied significantly between individuals. In conclusion, postprandial lipemia after a single fatty meal was associated with procoagulatory change in F VILC but there was no difference between saturated fat and n-6 polyunsaturated fat.

Involvement of insulinemia in the postprandial hypotriacylglycerolemia induced by prazosin in the rat

The purpose of the present study was to evaluate the role of insulin as a possible mediator of the hypotriacylglycerolemic effect of α 1-adrenergic blockade. To this end, determinants of triacylglycerol (TG) metabolism were measured in animals having normal postprandial fluctuations in insulin levels (intact rats) and in others having invariable insulin concentrations (insulin-depleted rats infused long-term with insulin-delivering minipumps). Postprandial changes in plasma TG level, TG secretion rate (TGSR), TG elimination rate (TGER), and lipoprotein lipase (LPL) activity of white (WAT) and brown (BAT) adipose tissues, vastus lateralis muscle (VLM), and heart were measured in animals acutely injected or not with the α 1-antagonist prazosin 1 hour before the intake of a high-sucrose, fat-free meal. In intact rats, postprandial increases in glucose and insulin levels were potentiated by administration of prazosin before meal intake. The postmeal increase of plasma TG level was abolished by prazosin in intact animals, whereas this effect was absent in animals with invariable insulin levels. Intact animals treated with prazosin displayed both a lower TGSR ( P < .01) and a higher TGER ( P < .01) than their saline-injected counterparts. In animals with invariable insulin, both TGSR and TGER remained unaffected by prazosin treatment. Prazosin treatment of intact animals did not affect LPL activity in WAT, but increased enzyme activity in BAT ( P < .02). In insulin-infused animals, prazosin increased LPL activity in WAT ( P < .02) and BAT ( P < .03). α 1-Adrenergic blockade had no effect on LPL in VLM and heart. These results confirm that α 1-adrenergic blockade prevents the postprandial increase in plasma TG level that follows the ingestion of a high-sucrose meal both by decreasing TGSR and by increasing TGER. The findings also demonstrate that these effects of prazosin are indirect and that their occurrence requires the postprandial increase in circulating insulin levels.

Postprandial plasma triacylglycerols in rats under alpha 1-adrenergic blockade

The present studies evaluated the effect of prazosin, a selective alpha 1-adrenergic antagonist, on some metabolic determinants of triacylglycerol-rich lipoproteins. Plasma triacylglycerols (TG), TG secretion rate, TG removal rate, plasma insulin, and glucose were evaluated postprandially in animals fed a high-sucrose meal. In the fasted state plasma TG, glucose, and insulin concentrations were minimally affected by prazosin. There was a significant postprandial elevation in plasma TG levels that was larger after ingestion of a meal containing corn oil than after intake of a fat-free meal. Prazosin totally blunted the postprandial elevation in plasma TG independently of the presence (P < 0.004) or absence of dietary fat (P < 0.01). In the postprandial phase after ingestion of a fat-free, high-sucrose meal, prazosin decreased the rate of secretion of TG into the circulation (-54%, P < 0.0003) and accelerated twofold the clearance of an injected fat emulsion (P < 0.02). The postprandial elevations in plasma insulin and glucose were significantly potentiated by administration of prazosin before intake of the fat-free meal. These results indicate that prazosin prevented the postprandial elevation in plasma TG that followed the ingestion of a high-sucrose meal. The results also demonstrate that the alpha 1-blocker exerted its action both by decreasing TG secretion and by increasing the rate of removal of circulating TG.

A kinetic model of chylomicron core lipid metabolism in rats: the effect of a single meal

A detailed quantitative description of the metabolism of the core lipids of chylomicrons was developed with data obtained from rats injected intravenously with radioactive chylomicrons. Groups of recipient rats were starved or else fed a single meal that was either fat-free or contained 5% fat. The kinetic model included chains of delipidation compartments and a remnant particle. Compartments for recirculation of portions of triglyceride, cholesteryl ester, and unesterified fatty acid radioactivities were all included and necessary to obtain good fits to the data. Making the simplifying assumption that remnants could be represented as particles retaining cholesteryl esters but depleted in triglycerides, a 'delipidation index' was calculated as the ratio of the cholesteryl ester residence time divided by the triglyceride residence time. Significant differences were found in the delipidation index between the starved group and both the normal-fed and fat-free-fed groups. Compared with rats fed a meal of the usual diet which contained 5% fat, starved rats showed more extensive delipidation and a trend toward a longer residence time of remnant particles. A longer residence time of triglycerides in rats fed a fat-free meal was explained by less delipidation, but remnant removal appeared to be accelerated. The kinetic model makes possible an interpretation of the patterns of metabolism in terms of the known underlying physiological mechanisms.

Acute postprandial lipaemia does not influence the [formula omitted] activity of human platelets

Platelet function and serum lipid studies were conducted on nine healthy male subjects before and two hours after three separate meals, two of which were rich in fat: saturated fat (SF) or polyunsaturated fat (PUF), and a third control meal which contained no fat. Platelet activity was assessed by determination of in vivo platelet aggregate formation, and plasma levels of the platelet specific proteins platelet factor 4 (PF 4) and β-thromboglobulin (β-TG). Serum triglyceride levels increased significantly after both fat containing meals but were unaffected by the fat free meal. Serum cholesterol levels were not affected by any of the three meals. Platelet function tests could not detect any alteration of in vivo platelet activity in terms of platelet aggregate formation or plasma concentrations of PF 4 and β-TG. These results are at variance with previously published studies that used less specific assays of platelet activity and which suggested platelet activation shortly after meals rich in SF.

Intestinal contribution to secretion of very low density lipoproteins into plasma.

To resolve the question of the magnitude of the intestine's contribution to circulating very low density lipoproteins (VLDL), measurements of intestinal, hepatic, and total VLDL--triglyceride were made on the same animals or on animals studied under comparable conditions. Animals were examined in the fasted state and during infusion of a fat-free meal. Intestinal VLDL secretion was determined through timed collections of lymph from the mesenteric lymph duct; hepatic and total VLDL secretion rates were estimated by the accumulation of plasma VLDL after injections of Triton WR 1339. Results indicate that the intestine contributes only a minor portion (11%) of the amount of triglyceride entering into the plasma compartment in the fasted state. Although intestinal triglyceride production is increased by 50% (p less than 0.01) in fed rats, the overall contribution of the intestine is not significantly altered in fed rats and represents only 14--17% of total body VLDL secretion. Thus, although intestinal VLDL secretion can be modified experimentally, its total impact on endogenous triglyceride production in normotriglyceridemic rats is small.

Gallstones in children; report of four cases.

The occurrence of cholelithiasis in childhood is rare. However, in patients with unexplained abdominal pain or jaundice it should not be forgotten in the differential diagnosis, particularly since the accurate diagnosis by cholecystography is simple and the surgical results are excellent. The presence of jaundice is far more commonly due to hepatocellular disease in children, but the possibility of cholecystitis, with or without cholelithiasis, should be kept in mind. Diagnosis It may be possible to demonstrate calcified stones in the gall-bladder region by using posteroanterior, oblique, and lateral projections. Harris and Caffey 1 reported that the results of cholecystography using iodopanoic acid (Tel[ill]paque) were excellent in children more than 11 months of age. The usual dosage of iopanoic acid (Telepaque) was 0.15 gm. per kilogram of body weight in younger children. In older children 4 to 6 tablets were given the evening before with fat-free meal followed by filming in

Clinical and Roentgenologic Evaluation of Routine 2-Gram Telepaque Dosage in Cholecystography

Early clinical evaluation and comparison with Priodax demonstrated the much denser gallbladder shadows found after ingestion of Telepaque in 3-gm. dosage and also showed a high incidence of unabsorbed contrast material in the colon. These findings pointed to the possibility that the 3-gm. dosage might be excessive, and it was suggested by others and concurred in by us that a thorough trial of a smaller dosage was indicated (1–6). Accordingly, a routine 2-gm. dosage was instituted at the University Hospital. Following the trial period for accumulation of data, this proved so satisfactory that it has been continued as standard cholecystographic procedure. A previous study at this institution (6) evaluated the side-effects of the 3-gm. dose of Telepaque in comparison with an equal dose of Priodax. Under identical conditions, cholecystographic subjects were interviewed by a physician as they passed through the gastrointestinal suite, and the side-effects of the 2-gm. dosage were tabulated. The contrast material was ingested exactly as in the previous study, i.e., following a fat-free meal the evening prior to examination. The incidence of side-effects as compared with the earlier Priodax and Telepaque (3-gm.) series is presented in Table I. The comparative figures show a small increase over the 3-gm. Telepaque group in absence of side-effects and a slight decrease in the two more frequent effects, mild diarrhea and mild dysuria, the reductions in these symptoms being in the neighborhood of 4 to 5 per cent. Thus it appears that the smaller 2-gm. dose enjoys an advantage in this respect when used as a routine procedure. The other chief concern in use of the reduced dosage is its effect on the density of the gallbladder shadow. A review of 500 examinations was carried out with the same standards employed in our previous studies (6), and gallbladder visualization was classified under the same headings: excellent, good, faint, or non-visualization, for each examination. The presence of stones was also recorded and it was noted whether they were radiolucent, radiopaque, or mixed. The incidence of residual contrast material in the colon was tabulated. Gallbladder visualization with 2-gm. dosage is compared with the previous study of 3-gm. dosage in Table II. While there appears to be a 13 per cent decrease in the “excellent” category, an increase of 9.2 per cent is noted in the “good” results. If the excellent and good classifications are combined and considered as “satisfactory” the 3-gm. dosage shows an advantage of 3.8 per cent over the 2-gm. dosage, S3 as compared to 79.2 per cent. This small decrease in diagnostic shadows with the lower dosage may be counterbalanced by the risk of obscuring stones by the dense shadows produced by 3 gm. Of the 500 patients receiving 2 gm., 487, or 97.4 per cent, showed residual contrast medium in the colon.