[Validation of the French version of the Binge Eating Scale: Examination of its factor structure, internal consistency and construct validity in a non-clinical and a clinical population]

OBJECTIVE

The Binge Eating Scale is a widely used scale to assess binge eating disorder in obese patients. Until now, this scale has not been validated on a French population, and no psychometrically sound tool assesses binge eating disorder in the French. This study aimed to test the psychometric properties of a French version of the Binge Eating Scale by establishing its factor structure, internal consistency, and construct validity in both a non-clinical population and a clinical population (obese patients who are candidates for bariatric surgery).

METHODS

A total of 553 non-clinical subjects and 63 morbidly obese patients who were candidates for bariatric surgery were assessed with the BES and the Bulimic Investigatory Test, Edinburgh or BITE (which assesses both binge eating behaviours and use of inappropriate compensatory behaviours). We tested the factor structure of the instrument, its internal consistency, its construct validity with measures of binge eating, and its construct validity with measures of inappropriate compensatory behaviours to avoid weight gain. In 47 out of the 63 obese patients, we assessed binge eating disorder (SCID).

RESULTS

In the non-clinical population, the BES had a one-factor structure (which accounted for 61% of the variance), excellent internal consistency (α=0.93), and high construct validity with measures of binge eating. In this population, construct validity with measures of inappropriate compensatory behaviours was confirmed in overweight and obese subjects (P=0.42), but not in underweight and optimal weight subjects (P<0.001). In obese patients candidates for bariatric surgery, we demonstrated that the BES had a one-factor structure (which accounted for 46% of the variance), had high internal consistency (α=0.88) and high construct validity with measures of binge eating and good construct validity with measures of inappropriate compensatory behaviours to avoid weight gain. In the subpopulation of 47 obese patients, sensitivity, specificity, positive predictive value and negative predictive value were respectively 75%, 88.4%, 37.5% and 97.4% (BES threshold=18).

DISCUSSION

In this study, we validated a psychometrically sound French version of the Binge Eating Scale, both in a non-clinical and a clinical sample. The psychometric properties of the French version of the BES are comparable to its original version with a one-factor structure. The BES is a useful tool to assess binge eating disorder in obese patients (e.g., bariatric surgery candidates), but might not differentiate between binge eating disorder and bulimia nervosa in underweight and optimal weight subjects.

Physical activity and weight loss following bariatric surgery

Physical activity is a cornerstone in the medical management of obesity and could be important for weight loss following bariatric surgery. This review aims to describe the evolution of physical activity following massive weight loss induced by bariatric surgery, and to identify the relationship between physical activity and amount of weight loss. A literature search identified 20 publications (19 studies) reporting physical activity data in relation to bariatric surgery. All studies were observational. Self-assessment of physical activity was used in all the studies. Objective measures (pedometry) were used in two studies. The time frame for physical activity assessment varied: before surgery in two publications, after surgery in nine, and longitudinal pre- to post-operative evolution in nine. The latter nine publications found an increase in physical activity after bariatric surgery. In 10/13 studies where it was described, there was a positive relationship between physical activity level and amount of weight loss. In conclusion, observational evidence of self-reported physical activity suggests that physical activity increases after bariatric surgery and that physical activity is associated with surgically induced weight loss. However, these findings warrant further evaluation using objective measures of physical activity and testing in controlled trials.

[Diabetic amyotrophy: favorable outcome following corticosteroid therapy?]

Diabetic amyotrophy or lombosacral radiculoplexus neuropathy is a rare complication associated with early-stage diabetes. Thigh pain, quadricipital amyotrophy, proximal weakness of lower limbs and weight loss are the main symptoms of the disease. As neurological damage is related to inflammatory microvasculitis, corticosteroid therapy may be considered as the first line therapy. We report a 54-year-old patient with type 2 diabetes affected with severe diabetic amyotrophy. Following intravenous corticosteroid therapy, the patient reported a rapid pain relief and gained muscle strength.

The cumulative effect of small dietary changes may significantly improve nutritional intakes in free-living children and adults

BACKGROUND/OBJECTIVES

The ELPAS (Etude Longitudinale Prospective Alimentation et Santé) study was an 8-month randomized controlled dietary modification trial designed to test the hypothesis that family dietary coaching would improve nutritional intakes and weight control in 2026 free-living children and parents. It resulted in significant nutritional changes, with beneficial effects on body mass index in adults. In these ancillary analyses, we investigated dietary changes throughout the intervention.

SUBJECTS/METHODS

Before the study, modeling analyses were carried out on the French Association Sucre Produits Sucrés Consommation et Communication (ASPCC) food-consumption database to identify the most efficient dietary intervention strategy. During the study, all participants performed monthly three nonconsecutive 24-h dietary recalls: this allowed for measuring changes in the number of servings per day and serving size for each targeted food category throughout the intervention.

RESULTS

Modeling analyses showed that targeting only the 10 main foods contributing to fat and carbohydrate intakes did not allow for reaching the ELPAS nutritional goals. As a result, it was decided to target more foods and to propose several types of dietary advice (such as change in serving size, change in cooking method, food substitution). This strategy led to many appropriate dietary changes during the intervention, but only a few of them reached significance. The mean number of servings per day was indeed significantly modified for only 7% of the targeted food categories in children and 17% in parents. The mean serving size was modified for only 12% of targeted food categories in children and 9% in parents.

CONCLUSIONS

The cumulative effect of small dietary changes may induce significant nutritional improvements, with limited burden for populations.

Changes in plasma triacylglycerol concentrations after sequential lunch and dinner in healthy subjects

OBJECTIVES

The present study examines the kinetic of plasma triacylglycerol (TAG) after sequential ingestion of lunch and dinner as well as the contribution of dietary fat ingested at lunch to subsequent post-dinner TAG composition.

METHOD

Six healthy subjects were included. After standardized breakfast (7: 30AM), 2 mixed meals with fat loads composed of 44 g olive oil (rich in oleic acid) at lunch (12PM) and 44 g sunflower oil (rich in linoleic acid) at dinner (7PM) were ingested. [1-13C] palmitate was added in lunch only. Plasma TAG and chylomicron-TAG (CMTAG) levels were measured sequentially after meals. [1-13C] palmitate enrichment and concentrations of oleic acid and linoleic acid were measured in all lipid fractions.

RESULT

Post-dinner plasma TAG peak was delayed as compared to lunch (3 hours vs 1 hour, p=0.002) whereas the magnitude of the postprandial peaks was not significantly different between lunch and dinner (2.4+/-0.3 vs 2.0+/-0.4 mmol/L, p=0.85). [1-13C] palmitate enrichment was maximal 5 hours after lunch in all lipid fractions and decreased slowly thereafter. After dinner ingestion, the rate of decline of [1-13C] palmitate enrichment plateaued during the first 60 minutes. Oleic acid increased slightly and immediately after dinner and remained the predominant fatty acid in all lipid fractions during the first hour after dinner. A delayed peak of plasma and CM-TAG was observed after dinner as compared to lunch without difference in the magnitude of peaks.

CONCLUSION

The contribution of dietary fat ingested at lunch to post-dinner lipemia is confirmed despite the relatively long lasting interval between the 2 meals (7 h) and the absence of any early peak of plasma TAG after dinner.

[Maternal mortality estimation in France, according to a new method]

OBJECTIVE

Ten years after implementation of maternal mortality monitoring in France, we established a new estimate of the current maternal mortality ratio (MMR) and revisited maternal death data collection.

MATERIAL AND METHODS

Linkages were set up between female deaths and childbirths and between female deaths and causes of death. Information provided by confidential inquiries into maternal deaths carried out by the National Committee for maternal mortality study was added. The World Health Organization (WHO) definitions were used for maternal death and maternal mortality ratio. The study concerned deaths occurring in 1999. Results were compared with data from 1989.

RESULTS

The official data showed 20% fewer maternal deaths than our inquiry. Estimated from our data, the MMR was 9 per 100000 live births in 1999. Direct obstetric causes were more often recorded than indirect causes. Hemorrhage was the leading obstetric cause of maternal death (21%). In comparison with the 1989-90 data, the underestimation of maternal deaths and maternal mortality ratios are improving (from 18 to 9 per 100000).

CONCLUSION

These results, obtained while the mean maternal age at childbirth increased regularly, are interpreted as a sign of improvement in care. But the persistence of post partum hemorrhages as the leading cause of maternal death and the high rate of avoidable deaths, disclose important targets for further progress.

"Big IGF-II"-induced hypoglycemia secondary to gastric adenocarcinoma

Non-islet cell tumor-related hypoglycemia is a rare phenomenon. We report the case of a 63 Year-old man admitted for hemiparesia and a capillary blood glucose of 20 mg/dL. The presence of an immature form of IGF-II that can mimic the effect of insulin, namely "big IGF-II", explained this patient's hypoglycaemia. A moderately differentiated adenocarcinoma of the cardia with metastatic extension to the stomach and the liver was demonstrated. Octreotide failed to control the hypoglycaemia, therefore prednisolone (2 mg/kg per day) and enteral feeding prevented new episodes of severe hypoglycaemia.

Association between trans fatty acid intake and cardiovascular risk factors in Europe: the TRANSFAIR study

BACKGROUND

High intakes of trans fatty acids (TFA) have been found to exert an undesirable effect on serum lipid profiles, and thus may increase the risk for cardiovascular disease.

OBJECTIVES

Investigation of the association between TFA intake and serum lipids.

DESIGN

Cross-sectional study in eight European countries (Finland, France, Greece, Iceland, The Netherlands, Portugal, Spain, Sweden) among 327 men and 299 women (50-65 y). Using a dietary history method, food consumption was assessed and TFA intake was calculated with recent figures on TFA levels of foods, collected in the TRANSFAIR study.

RESULTS

Mean (+/-s.d.) TFA intake was 2.40+/-1.53 g/day for men and 1.98+/-1.49 g/day for women (0.87+/-0.48% and 0. 95+/-0.55% of energy, respectively), with the highest consumption in Iceland and the lowest in the Mediterranean countries. No associations were found between total TFA intake and LDL, HDL or LDL/HDL ratio after adjustment for cardiovascular risk factors. Additional adjustment for other fatty acid clusters resulted in a significant inverse trend between total TFA intake and total cholesterol (Ptrend<0.03). The most abundantly occurring TFA isomer, C18:1 t, contributed substantially to this inverse association. The TFA isomers C14:1 t9, C16:1 t9 and C22:1 t were not associated or were positively associated with LDL or total cholesterol.

CONCLUSIONS

From this study we conclude that at the current European intake levels of trans fatty acids they are not associated with an unfavourable serum lipid profile.

SPONSORSHIP

Unilever Research Laboratorium, the Dutch Dairy Foundation on Nutrition and Health, Cargill BV, the Institute of Food Research Norwich Laboratory, the Nutrition Branch of the Ministry of Agriculture, Fisheries and Food, the International Fishmeal and Oil Manufacturers' Association, Kraft Foods, NV Vandemoortele Coordination Center, Danone Group, McDonalds Deutschland Inc, Danish Veterinary and Food Administration, Valio Ltd, Raisio Group. European Journal of Clinical Nutrition (2000) 54, 126-135

Effects of an amino acid dialysate on leucine metabolism in continuous ambulatory peritoneal dialysis patients

BACKGROUND

Protein-energy malnutrition is frequent in continuous ambulatory peritoneal dialysis (CAPD) patients. The use of amino acids in the dialysate could improve the protein balance, especially if associated to a concomitant energy intake.

METHODS

A 1.1% amino acid solution for peritoneal dialysis was administered to CAPD patients over 30 minutes during concomitant absorption of 600 ml water (control study) or of a 600 kcal meal/600 ml. Leucine metabolism was studied using the combination of intravenous [2H3] and intraperitoneal [13C] leucine.

RESULTS

The rate of leucine appearance was stimulated by 56 and 53% (control and meal) at 45 minutes. The rates of leucine appearance and disappearance were lower from 180 to 300 minutes during the meal versus control study (P < 0.05). Proteolysis was unaffected during the control study and was inhibited by 25% during the meal study (P < 0.05). During the five-hour cycle dialysis with or without a meal, 80% of the leucine administered into the peritoneum was absorbed. Forty-one percent was retained in the splanchnic bed. Forty-three percent was used for protein synthesis, and 16% was oxidized.

CONCLUSIONS

This amino acids solution is efficaciously utilized for protein synthesis in CAPD patients with no effect on protein breakdown. The concomitant ingestion of a carbohydrate-lipid meal inhibits protein breakdown and reinforces a positive effect of the amino acids solution on protein balance.

Fatty acid composition of white adipose tissue and breast milk of Mauritian and French mothers and erythrocyte phospholipids of their full-term breast-fed infants

The fatty acid compositions of white adipose tissue, colostrum and mature milk triacylglycerols from Mauritian (n 13) and French (n 15) women were analysed and compared in order to highlight cultural differences in dietary intakes and their influence on milk fatty acid composition. Erythrocyte phosphatidylethanolamine and phosphatidylcholine fatty acid compositions were also investigated in their term infants, breast-fed over a period of 6 weeks. Fatty acid composition (g/100 g) of all samples was determined by GLC and anthropometric measurements were assessed in the two populations at birth and on day 42. Comparisons of white adipose tissue fatty acid compositions demonstrated lower levels of saturated (23.64 (SE 1.54) v. 29.75 (SE 0.67), P < 0.01) and monounsaturated (39.44 (SE 1.27) v. 54.84 (SE 0.75), P < 0.001) fatty acids and higher levels of polyunsaturated fatty acids (n-6 series: 32.47 (SE 1.31) v. 14.32 (SE 0.47), P < 0.001 and n-3 series: 2.87 (SE 0.49) v. 0.80 (SE 0.07), P < 0.01) in Mauritian than in French samples respectively. Accordingly, milk fat of the Mauritian women contained higher levels of parent essential fatty acids and their longer-chain derivatives than did milk fat from French women. Higher levels of parent essential fatty acids but lower levels of long-chain polyunsaturated fatty acids were found in erythrocyte phospholipids of Mauritian infants compared with French infants. Infants' erythrocyte arachidonate and docosahexaenoate contents did not correlate with any anthropometric variables at birth or at day 42, neither did they correlate with anthropometric variation over the study period. Our results suggest the lack of a simple relationship between the amount of long-chain polyunsaturated fatty acids in human milk and their accretion in the erythrocyte phospholipids of breast-fed infants when provided concomitantly with high levels of both linoleic and alpha-linolenic acids in ratios which fall within recommended ranges.

Blood lipid concentrations of docosahexaenoic and arachidonic acids at birth determine their relative postnatal changes in term infants fed breast milk or formula

BACKGROUND

Factors other than dietary fatty acids could be involved in the variability observed in blood docosahexaenoate (22:6n-3) and arachidonate (20:4n-6) status in formula-fed infants.

OBJECTIVE

We considered the 22:6n-3 and 20:4n-6 status at birth to be one of these factors and studied its influence on postnatal changes in term infants fed 4 different diets.

DESIGN

The blood phospholipid composition was determined at birth and on day 42 of feeding in 83 term infants fed breast milk, nonsupplemented formula, or 2 different 22:6n-3-supplemented formulas. Relations between 22:6n-3 and 20:4n-6 status at birth and their relative postnatal changes, calculated by the difference between status at the end of the feeding period (6 wk of age) and at birth, were assessed.

RESULTS

Postnatal changes in the plasma and erythrocyte phospholipids 22:6n-3 and 20:4n-6 were negatively related to their respective concentrations at birth (P < 0.01) and the slopes of the regression lines were not significantly affected by the type of milk ingested. Adjusted mean values for phospholipid 22:6n-3 in nonsupplemented-formula-fed infants and for 20:4n-6 in formula-fed infants decreased significantly more than they did in the other infant groups (P < 0.02). The status at birth and the type of milk ingested explained 33-64% and 7-47%, respectively, of the variability in postnatal changes.

CONCLUSIONS

The status of 22:6n-3 and 20:4n-6 at birth in term infants is one of the major determinants of postnatal changes in these fatty acids. This finding indicates that research is required to characterize environmental, genetic, or both factors, which, in addition to maternal diet, could influence fatty acid status at birth.

Intake of fatty acids in western Europe with emphasis on trans fatty acids: the TRANSFAIR Study

OBJECTIVE

To assess the intake of trans fatty acids (TFA) and other fatty acids in 14 Western European countries.

DESIGN AND SUBJECTS

A maximum of 100 foods per country were sampled and centrally analysed. Each country calculated the intake of individual trans and other fatty acids, clusters of fatty acids and total fat in adults and/or the total population using the best available national food consumption data set.

RESULTS

A wide variation was observed in the intake of total fat and (clusters) of fatty acids in absolute amounts. The variation in proportion of energy derived from total fat and from clusters of fatty acids was less. Only in Finland, Italy, Norway and Portugal total fat did provide on average less than 35% of energy intake. Saturated fatty acids (SFA) provided on average between 10% and 19% of total energy intake, with the lowest contribution in most Mediterranean countries. TFA intake ranged from 0.5% (Greece, Italy) to 2.1% (Iceland) of energy intake among men and from 0.8% (Greece) to 1.9% among women (Iceland) (1.2-6.7 g/d and 1.7-4.1 g/d, respectively). The TFA intake was lowest in Mediterranean countries (0.5-0.8 en%) but was also below 1% of energy in Finland and Germany. Moderate intakes were seen in Belgium, The Netherlands, Norway and UK and highest intake in Iceland. Trans isomers of C18:1 were the most TFA in the diet. Monounsaturated fatty acids contributed 9-12% of mean daily energy intake (except for Greece, nearly 18%) and polyunsaturated fatty acids 3-7%.

CONCLUSION

The current intake of TFA in most Western European countries does not appear to be a reason for major concern. In several countries a considerable proportion of energy was derived from SFA. It would therefore be prudent to reduce intake of all cholesterol-raising fatty acids, TFA included.

Effect of two types of fish oil supplementation on plasma and erythrocyte phospholipids in formula-fed term infants

We studied the effect of docosahexaenoic acid (DHA) supplementation of infant formulas on fatty acid composition of blood phospholipids in term infants. Two fish oil supplemented formulas containing 0.45 wt% DHA and high (0.35%) or low (0.10%) eicosapentaenoic acid (EPA) were fed for 42 days and compared with a standard formula and breast milk. Infants fed supplemented formulas and breast milk had similar time-dependent changes for DHA from birth to day 42, i.e., slight decreases in plasma phospholipids and erythrocyte phosphatidylcholine and no change in erythrocyte phosphatidylethanolamine. Low-EPA formula prevented EPA accumulation but did not limit the significant decrease in arachidonic acid (AA) noted in infants fed high-EPA formula. These results suggest that term infant formulas should be supplemented with DHA-rich EPA, low fish oil and AA to achieve a fatty acid status in formula-fed infants similar to that of breast-fed infants.

Effects of oral glucose on intermediary metabolism in continuous ambulatory peritoneal dialysis patients versus healthy subjects

OBJECTIVE

To explore the mechanisms and metabolic consequences of the insulin resistance of patients treated by continuous ambulatory peritoneal dialysis (CAPD).

DESIGN

CAPD patients and healthy subjects ingested a similar mean oral glucose load per kilogram of fat-free mass (FFM) [1.20+/-0.03 g/(kg FFM) vs 1.20+/-0.06 g/(kg FFM); CAPD vs healthy subjects]. Substrate oxidation was monitored over 6 hours using indirect calorimetry.

SETTING

Peritoneal dialysis unit of a tertiary-care institutional center.

OUTCOME MEASURES

Glycemia, insulinemia, substrate oxidation.

PATIENTS

Six CAPD patients (68+/-5 yr) and 6 healthy subjects (24+/-1 yr). The CAPD patients had similar body mass index (21.4+/-1.3 vs 22.9+/-1.1 kg/m2), a higher percent fat (25.8%+/-3.7% vs 16%+/-2.2%; p < 0.05), and a lower FFM (42.2+/-2.2 kg vs 56.5+/-2.6 kg; p < 0.01) than healthy subjects.

RESULTS

The CAPD patients displayed a higher glycemic and insulinemic responses to glucose than did healthy subjects (p < 0.05), but similar glucose oxidation and storage. Lipid oxidation and plasma nonesterified fatty acids were not increased in CAPD patients versus healthy subjects, in spite of a higher adiposity. Fat oxidation was related to fat mass in CAPD patients (r2 = 0.77, p < 0.05) but not in healthy subjects (r2 = 0.05).

CONCLUSION

CAPD patients display an insulin-resistance not explained by an increased lipid oxidation. The maintenance of intracellular glucose utilization at the expense of higher glycemic and insulinemic responses suggests a defective glucose transport.

Long-term supplementation of culture medium with essential fatty acids alters α-linolenic acid uptake in Caco-2 clone TC7

We investigated the influence of four different culture media: 20% fetal bovine serum (FBS), 5% FBS, 5% FBS supplemented with 10 mg·L-1 linoleic acid (18:2(n-6)) or alpha-linolenic acid (18:3(n-3)) on alpha-linolenic acid apical uptake in clone TC7 of human intestinal Caco-2 cell line. Neither cellular viability nor cell monolayer integrity and permeability were altered by the four culture conditions. Our results show that the different culture media led to changes in alpha-linolenic acid maximal rate of uptake (Vmax) but did not alter the apparent transport constant (Km). Reducing FBS concentration from 20% to 5% increased significantly the rate of alpha-linolenic acid uptake, which was further increased by supplementation of the medium with 18:2(n-6) or 18:3(n-3). Supplementation with essential fatty acids led to a marked enrichment of brush-border membrane phospholipids in polyunsaturated fatty acids of the corresponding series and decreased significantly the levels of monounsaturated fatty acids. Saturated fatty acids, unsaturation index, and cholesterol / fatty acid ratios were unchanged. No clear relation could be established between the changes in membrane lipid composition and the alterations of alpha-linolenic acid uptake. These results indicate a weak influence of membrane lipid composition in the modulation of the uptake. Therefore, the increase of uptake following long-term supplementation of TC7 cells with essential fatty acids could be attributed to an increase of the expression of membrane protein(s) involved in the apical uptake of long-chain fatty acids. This remains to be established.Key words: fatty acid intestinal absorption, Caco-2 cells, membrane fatty acid transport protein, membrane phospholipid fatty acid composition.

Long-term supplementation of culture medium with essential fatty acids alters alpha-linolenic acid uptake in Caco-2 clone TC7

We investigated the influence of four different culture media: 20% fetal bovine serum (FBS), 5% FBS, 5% FBS supplemented with 10 mg x L(-1) linoleic acid (18:2(n-6)) or alpha-linolenic acid (18:3(n-3)) on alpha-linolenic acid apical uptake in clone TC7 of human intestinal Caco-2 cell line. Neither cellular viability nor cell monolayer integrity and permeability were altered by the four culture conditions. Our results show that the different culture media led to changes in alpha-linolenic acid maximal rate of uptake (Vmax) but did not alter the apparent transport constant (Km). Reducing FBS concentration from 20% to 5% increased significantly the rate of alpha-linolenic acid uptake, which was further increased by supplementation of the medium with 18:2(n-6) or 18:3(n-3). Supplementation with essential fatty acids led to a marked enrichment of brush-border membrane phospholipids in polyunsaturated fatty acids of the corresponding series and decreased significantly the levels of monounsaturated fatty acids. Saturated fatty acids, unsaturation index, and cholesterol/fatty acid ratios were unchanged. No clear relation could be established between the changes in membrane lipid composition and the alterations of alpha-linolenic acid uptake. These results indicate a weak influence of membrane lipid composition in the modulation of the uptake. Therefore, the increase of uptake following long-term supplementation of TC7 cells with essential fatty acids could be attributed to an increase of the expression of membrane protein(s) involved in the apical uptake of long-chain fatty acids. This remains to be established.

Effect of dietary fish oil on body fat mass and basal fat oxidation in healthy adults

OBJECTIVE

To investigate whether the substitution of fish oil for visible fats in a control diet (52% carbohydrates, 16% protein, 32% fat; P:S 0.2) influences body fat mass and substrate oxidation in healthy adults.

DESIGN

Six volunteers (5 men; 23 +/- 2 y; BMI: 21.9 +/- 1.6) were fed a control diet (C) ad libitum during a period of three weeks and, 10-12 weeks later, the same diet where 6 g/d of visible fat were replaced by 6 g/d of fish oil (FO) for another three weeks.

RESULTS

Energy intakes (IKA-calorimeter) were unchanged. Body fat mass (Dual-energy X-ray absorptiometry) decreased with FO (-0.88 +/- 0.16 vs -0.3 +/- 0.34 kg; FO vs C; P < 0.05). When adjusted for lean body mass (Ancova), resting metabolic rate (indirect calorimetry) was unchanged. Basal respiratory quotient decreased with FO (0.815 +/- 0.02 vs 0.834 +/- 0.02; P < 0.05) and basal lipid oxidation increased with FO (1.06 +/- 0.17 vs 0.87 +/- 0.13 mg kg(-1) min(-1); P < 0.05).

CONCLUSION

Dietary FO reduces body fat mass and stimulates lipid oxidation in healthy adults.

Processing/activation of CPP32-like proteases is involved in transforming growth factor beta1-induced apoptosis in rat hepatocytes

Apoptosis induced in rat hepatocytes by transforming growth factor beta1 (TGF-beta1) was accompanied by the activation of interleukin-1beta converting enzyme (ICE)-like proteases. Cell lysates were isolated at various times after TGF-beta1 treatment and analyzed for ICE and CPP32-like activity, using N-acetyl-Tyr-Val-Ala-Asp-7-amino-4-methylcoumarin (Ac-YVAD.AMC) and benzyloxycarbonyl-Asp-Glu-Val-Asp-7-amino-4-trifluoromethylcoumarin (Z-DEVD.AFC), respectively. CPP32-like but not ICE protease activity increased in a time dependent manner and preceded the onset of apoptosis. Kinetic studies in cell lysates indicated that more than one CPP32-like protease was being activated. This was confirmed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE)/Western blotting of TGF-beta1-treated cells, which showed limited processing of CPP32 as shown by the appearance of the catalytically active p17 subunit. Loss of pro-Mch3alpha was also observed but the catalytically active p19 subunit was not detected. Staurosporine, which induced a much greater level of hepatocyte apoptosis, produced a concomitant increase in CPP32/Mch3alpha processing as shown by the appearance of the p17/p19 subunits and the corresponding increase in CPP32-like protease activity. Apoptosis, CPP32/Mch3alpha processing and the increase in CPP32-like protease activity induced by TGF-beta1 and staurosporine were abolished in hepatocytes pretreated with Z-Asp-Glu-Val-Asp (OMe) fluoromethylketone (Z-DEVD.FMK) or Z-Val-Ala-Asp (OMe) fluoromethylketone (Z-VAD.FMK). These peptide analogues were potent inhibitors of CPP32-like protease activity in lysates. Pretreatment of hepatocytes with cycloheximide also blocked TGF-beta1-induced apoptosis and the increase in CPP32-like activity. Unlike Z-VAD.FMK and Z-DEVD.FMK, cycloheximide did not inhibit CPP32-like protease activity in cell lysates. Thus, cycloheximide may block apoptosis by inhibiting the synthesis of a protein, which is involved in the upstream events responsible for the activation of the CPP32-like protease activity. Our studies have identified two of the CPP32-like proteases, namely CPP32 and Mch3alpha, which are activated during the execution phase of hepatocyte apoptosis.

Mechanisms and kinetics of alpha-linolenic acid uptake in Caco-2 clone TC7

The uptake kinetics of alpha-linolenic acid (18:3(n - 3)), an essential fatty acid, were investigated in the human intestinal cell line Caco-2. Four clones (PD10, PF11, PD7 and TC7) from the heterogeneous parental Caco-2 cells population were used. After a screening step using isolated cells, the TC7 clone was selected for the study of alpha-linolenic acid uptake. [1-(14)C]linolenic acid dissolved in 10 mM taurocholate was presented to the microvillus plasma membrane (apical side) of TC7 differentiated cells, grown on a semi-permeable polycarbonate membrane. The results show that the initial rate of uptake is not a linear function of the 18:3(n- 3) monomer concentration in the incubation medium. In the monomer concentration range studied (0.2 to 36 microM) apical uptake was saturable and followed Michaelis-Menten kinetics (V(max) = 15.4 +/- 0.6 nmol/mg protein per min, K(m) = 14.3 +/- 1.3 microM). In addition, it was temperature- and energy-dependent but was apparently unaffected by the sodium gradient and intracellular metabolic fate of 18:3(n - 3). Excess of unlabeled saturated or unsaturated long chain fatty acids (C16 to C22) led to a 27-68% reduction of [1-(14)C]linolenic acid uptake. Likewise basolateral uptake was saturable (V(max) = 4.9 +/- 0.7 nmol/mg protein per min, K(m) = 8.7 +/- 2.9 microM). These facts argue in favour of the existence in these human intestinal cells of a carrier-mediated transport system for alpha-linolenic acid and probably other long chain fatty acids as well.

Serum lipoprotein(a) [Lp(a)] in alcoholic men: effect of withdrawal

This study examines the effect of alcohol withdrawal on lipoprotein(a) [Lp(a)] in 24 male, middle-aged chronic alcohol abusers admitted for withdrawal therapy. Serum concentration of Lp(a) was determined before and during the first 3 weeks of abstinence. The changes in three sialylated proteins [Lp(a), alpha 1-antitrypsin (alpha 1-AT), and haptoglobin (Hp)] and in desialylated transferrin (CDT) were also determined in 14 patients. After the 3 weeks of withdrawal therapy, the mean and median Lp(a) concentrations increased (p = 0.0001). The changes in Lp(a) levels were not related to the changes in dietary intake nor to the decrease in total HDL, HDL3, HDL2 cholesterol, Apo A-I, and Apo B. In the subgroup of 14 chronic alcohol abusers, Lp(a) levels increased parallel with Hp and alpha 1-AT, whereas CDT decreased. It is concluded that the impact of alcohol on sialylated proteins may be one of the mechanisms responsible for the increase in plasma Lp(a) after alcohol withdrawal.

A novel method for detecting apoptosis shows that hepatocytes undergo a time dependent increase in DNA cleavage and chromatin condensation which is augmented after TGF-beta 1 treatment

This study describes a new method for quantitating apoptosis in hepatocyte monolayers in which nuclei were isolated from the cells and DNA strand breaks detected by in situ end-labeling and flow cytometry. Most (97%) nuclei from untreated hepatocytes had low end-labelling and were derived from non-apoptotic cells. Approximately 2-3% of the nuclei had high end-labelling and originated from apoptotic hepatocytes. The numbers of these nuclei increased linearly from 3 to 85% between 0 and 48 h after treatment with transforming growth factor-beta 1 (TGF-beta 1). However, a morphological assessment of apoptosis with Hoechst H33258 showed that the proportion of apoptotic nuclei plateaued at 18-19% between 24 and 48 h after TGF-beta 1 treatment. Thus, the in situ end-labeling technique also detected DNA cleavage in nuclei which did not have an obvious apoptotic morphology. Confocal microscopy of low and high end-labelled nuclei which had been separated by fluorescent cell sorting showed that nuclei with high levels of end-labeling exhibited a wide diversity of morphologies. These included nuclei with little or no chromatin condensation and nuclei with characteristic apoptotic morphology. In addition, nuclei from untreated hepatocytes contained low levels of DNA cleavage, which were localized in areas of condensed chromatin and increased according to the time in culture. Thus, hepatocytes undergo a progressive and cumulative process of DNA cleavage/chromatin condensation which is markedly enhanced by TGF-beta 1.

A cleavage-site-directed inhibitor of interleukin-1 beta-converting enzyme-like proteases inhibits apoptosis in primary cultures of rat hepatocytes

Apoptosis induced in primary hepatocytes by transforming growth factor beta1 and staurosporine produced chromatin condensation, DNA cleavage is detected by in situ end-labelling, field inversion and conventional gel electrophoresis, and cell detachment. These effects were abolished by benzyloxycarbonyl-valinylalanylaspartylfluoromethyl ketone, a cleavage-site-directed inhibitor of interleukin-1beta-converting enzyme-like proteases, and this finding suggests that these enzymes are involved in liver apoptosis.

Effects of free fatty acids on the metabolic response to oral fructose in lean healthy humans

OBJECTIVE

To study the effects of an experimental increase in plasma FFA concentration on fructose to glucose conversion, total hepatic glucose output and glycaemic response to oral fructose.

SUBJECTS

Six healthy subjects (three men, three women; age: 24.3 +/- 2.3 years; BMI: 21.6 +/- 0.8 kg/m2).

DESIGN

Each subject absorbed 0.5 g/kg of 13C-enriched fructose and randomly received either a triglyceride-heparin infusion or saline.

MEASUREMENTS

Total hepatic glucose output was traced with 6,6-2H2-glucose. Appearance in plasma of glucose synthesized from fructose was calculated from the isotopic enrichment in 13C of plasma glucose. Substrates oxidation was assessed with indirect calorimetry.

RESULTS

The triglycerides-heparin infusion increased FFA concentration before fructose as compared to saline (1086 +/- 40 vs 451 +/- 67 microM; p < 0.001) and lipid oxidation was 15% and 70% increased before and during fructose, respectively as compared to saline. Total hepatic glucose output, plasma appearance of glucose synthesized from fructose and glycaemic response were not affected. Glycogen storage over the first 3 h following fructose was increased (6.2 +/- 2.1 g vs 0.3 +/- 2.1 g; p < 0.01).

CONCLUSION

Triglycerides-heparin infusion did not stimulate plasma glucose appearance from fructose. Liver glucose-6-phosphate could have been produced in excess and diverted towards glycogen synthesis.

Effects of fish oil on metabolic responses to oral fructose and glucose loads in healthy humans

This study examines the effect of the substitution of 6 g/day of fish oil in a saturated diet on glucose and fructose metabolism in healthy humans. Five subjects were submitted to two 3-wk controlled-diet periods (polyunsaturated/saturated = 0.21). During one period, 6 g/day of fat used for dressing were replaced by 6 g/day of fish oil [1.1 g/day of 20:5 (n-3) fatty acids and 0.7 g/day of 22:6 (n-3) fatty acids]. At the end of each period the subjects ingested a 1 g/kg fructose or glucose load 2 days apart. Plasma glucose fluxes were traced with the use of deuterated glucose and [U-13C]glucose. Substrate oxidation was measured by indirect calorimetry. Fish oil induced a 4% increase in basal and postload glycemia and a 40% decrease in insulinemia, whereas plasma C-peptide remained unaffected. Glucose fluxes were unaffected by fish oil, but carbohydrate (CHO) oxidation was reduced (fructose: 55.5 +/- 4.1 vs. 62.9 +/- 3.6 g/6 h; glucose: 36.7 +/- 4.7 vs. 50.5 +/- 4.7 g/6 h; all P < 0.05). Lipid oxidation was increased 35% by fish oil after both CHO loads. Nonoxidative glucose disposal was increased by fish oil (fructose: 9.4 +/- 2.5 vs. 2.9 +/- 1.1 g/6 h; glucose: 28.3 +/- 5.1 vs. 14.4 +/- 4.7 g/6 h; all P < 0.05). Fish oil could affect glucose transport and decrease CHO oxidation through the decrease in insulinemia and/or a specific effect on glycolytic pathway.

Precision of DLW energy expenditure measurements: contribution of natural abundance variations

Accuracy and precision of the the doubly labeled water (DLW) measurements of energy expenditure are commonly estimated with models that do not account for 2H and 18O natural abundance variation. A new and simple treatment that completes the ratio-product model is derived in the present study. It uses both linear regression of multipoint data with time and information on within-subject 2H and 18O natural abundance variation. Use of this treatment is demonstrated in a group of seven subjects in whom 2H and 18O natural abundance variation was assessed by collecting predose samples for 6-8 days before dosing. In this set of 16 measurements, the precision (coefficient of variation) of individual DLW estimates of CO2 production was 4.90 +/- 2.14%, of which 3.23 +/- 1.20% arose from natural abundance variation.

Linoleic acid uptake by isolated enterocytes: influence of alpha-linolenic acid on absorption

In a previous study we showed that intestinal uptake of alpha-linolenic acid (18:3n-3) was carrier-mediated and we suggested that a plasma membrane fatty acid protein was involved in the transport of long-chain fatty acids. To further test this hypothesis, the mechanism of linoleic acid (18:2n-6) uptake by isolated intestinal cells was examined using a rapid filtration method and 20 mM sodium taurocholate as solubilizing agent. Under these experimental conditions transport of [1-14C]linoleic acid monomers in the concentration range of 2 to 2220 nM was saturable with a Vm of 5.1 +/- 0.6 nmol/mg protein/min and a Km of 183 +/- 7 nM. Experiments carried out in the presence of metabolic inhibitors, such as 2,4-dinitrophenol and antimycin A, suggested that an active, carrier-mediated mechanism was involved in the intestinal uptake of this essential fatty acid. The addition of excess unlabeled linoleic acid to the incubation medium led to a 89% decrease in the uptake of [1-14C]linoleic acid, while D-glucose did not compete for transport into the cell. Other long-chain polyunsaturated fatty acids added to the incubation mixture inhibited linoleic acid uptake by more than 80%. The presence of alpha-linolenic acid (18:3n-3) in the incubation medium caused the competitive inhibition (Ki = 353 nM) of linoleic acid uptake. The data are compatible with the hypothesis that intestinal uptake of both linoleic, and alpha-linolenic acid is mediated by a membrane carrier common to long-chain fatty acids.

alpha-Linolenic acid content of adipose breast tissue: a host determinant of the risk of early metastasis in breast cancer

The association between the levels of various fatty acids in adipose breast tissue and the emergence of visceral metastases was prospectively studied in a cohort of 121 patients with an initially localised breast cancer. Adipose breast tissue was obtained at the time of initial surgery, and its fatty acid content analysed by capillary gas chromatography. A low level of alpha-linolenic acid (18:3n-3) in adipose breast tissue was associated with positive axillary lymph node status and with the presence of vascular invasion, but not with tumour size or mitotic index. After an average 31 months of follow-up, 21 patients developed metastases. Large tumour size, high mitotic index, presence of vascular invasion and low level of 18:3n-3 were single factors significantly associated with an increased risk of metastasis. A Cox proportional hazard regression model was used to identify prognostic factors. Low 18:3n-3 level and large tumour size were the two factors predictive of metastases. These results suggest that host alpha-linolenic acid has a specific role in the metastatic process in vivo. Further understanding of the biology of this essential fatty acid of the n-3 series is needed in breast carcinoma.

Glucose oxidation after a peritoneal and an oral glucose load in dialyzed patients

Glucose oxidation and thermogenesis were studied after a peritoneal (P) and an oral (O) glucose load in nine chronically uremic patients undergoing continuous ambulatory peritoneal dialysis (CAPD) for 24.4 +/- 5.8 months. The O load (50 g) given was equivalent to the amount of glucose absorbed over six hours through the peritoneum of the subjects (51.7 +/- 3.3 g). Glucose oxidation and energy expenditure were obtained using indirect calorimetry in basal state and over the six hours following the glucose load. Glucose oxidation rate was higher from 60 to 180 minutes after O than after P (P < 0.05), with peak values of 3.85 +/- 0.28 mg.kg-1.min-1 and 2.80 +/- 0.17 mg.kg-1.min-1 respectively (P < 0.05). Cumulated glucose oxidation over six hours was 53.6 +/- 0.6 versus 47.0 +/- 3.4 g after O and P respectively (NS). Glucose-induced thermogenesis was 8.7 +/- 2.9% versus 5 +/- 1.9% after O and P, respectively (NS). The route of administration of glucose induces different kinetics of the glucose oxidation rate, but a similar amount of glucose absorbed either by the peritoneum or by the gut contributes in a similar extent to glucose and energy balance.

Anthropometric values in an elderly French population

We compared anthropometric indices in samples of elderly people aged 65 years and over living in two French areas. The samples were divided into four age-groups (65-69, 70-74, 75-79 and over 80 years). We observed interregional differences in women aged 65-69 years and in men aged 65-74 years. Weight and anthropometric variables related to body fat percentage and to muscle mass showed a decline with age as already reported by others. We established anthropometric percentile values according to sex in pooled subjects when no integrated difference was found. The 50th percentile of arm circumference, muscle arm circumference and triceps skinfold was higher, and the 50th percentile of body mass index was lower than the one reported for the same indices from an elderly Welsh population. Our results show that an interregional difference in anthropometric indices exists in the elderly. The differences which are observed between our results and those reported from a British population emphasize the importance of establishing local values for the elderly population.

Effect of calcium and mineral waters on oleic-acid uptake by isolated hamster enterocytes

The effect of calcium upon the uptake of oleic acid solubilized with 10 mM taurocholate was investigated using an in vitro model of isolated enterocytes. The addition of Ca2+ to the incubation medium (Hanks' medium) led to a decrease in oleic-acid uptake. This uptake inhibition was dependent on both the amount of Ca2+ and the fatty-acid concentration, since the inhibitory effect was significant for 10 microM but not 100 microM oleic acid. The determination of the monomeric activity of oleic acid indicated that the decrease in fatty-acid uptake was not linked to the formation of insoluble calcium soaps. The replacement of Hank's medium by several mineral waters containing between 0.3 and 11.7 mM Ca2+ significantly reduced the uptake of both 10 and 100 microM oleic-acid. The ionic composition of these waters was correlated with the decrease of initial rate of oleic acid uptake, but Ca2+ and other ions could interfere by synergetic effects with the fatty-acid-absorption mechanism. It is concluded that the ion-induced inhibition of oleic-acid uptake is not due to the formation of insoluble soaps but rather to a direct effect on the fatty-acid transport in membranes. Whether the fatty-acid binding protein in the plasma membrane is involved in the effect of Ca2+ on fatty-acid transport remains to be established.

Plasma lipids and alcohol consumption in alcoholic men: effect of withdrawal

This study examines the effect of alcohol withdrawal on plasma lipids and particularly on HDL-cholesterol subfractions, in 18 middle-aged, clinically healthy but chronically drinking men, institutionalized for withdrawal therapy. Plasma lipids, total HDL and HDL3-cholesterol, Apo A-I and Apo B were assayed before and after 30-86 days of abstinence. A 38% decrease in mean total HDL-cholesterol levels was observed after withdrawal therapy (P = 0.0002), and this was due mainly to a drop in HDL3-cholesterol concentrations (-43%, P = 0.0002). The decrease in HDL2-cholesterol concentrations was also significant (-21%, P < 0.005) but less marked. These results were not dependent on quantities of alcohol ingested before therapy, on duration of hospitalization and on changes in dietary fat intake or smoking habits. Apo A-I levels decreased (-39%, P = 0.0002) and the magnitude of the decrease after alcohol withdrawal was positively related to the duration of hospitalization. Apo B levels increased (+24%, P < 0.005). Among the anthropometric parameters, arm muscle area was significantly higher after alcohol withdrawal. The energy and macronutrient intakes did not significantly change during hospitalization. It is concluded that the modifications of HDL-cholesterol, HDL3-cholesterol, HDL2-cholesterol Apo A-I and Apo B values were induced by alcohol withdrawal in this population of chronic french alcoholics.

Dependence of human milk essential fatty acids on adipose stores during lactation

The relationships between essential fatty acid (EFA) composition of colostrum, mature milk, and white adipose tissue (WAT) were examined on days 5 and 30 postpartum in 24 healthy French mothers. Fatty acid composition was assessed by capillary gas chromatography. In WAT, the proportion of individual polyunsaturated fatty acids (PUFAs) did not change during lactation and was greater (18:2n-6) or lower (18:3n-3, long-chain PUFAs) than values found in colostrum or mature milk (P < 0.04). The 18:2n-6 content and the ratio of 18:3n-3 to 18:2n-6 correlated between WAT and colostrum (r = 0.52 and r = 0.57, respectively) or mature milk (r = 0.64 and r = 0.65, respectively). These relationships agree with an expected qualitative effect of WAT fatty acid composition on interindividual variability of milk parent EFA content. The decrease in the long-chain PUFA content observed from colostrum to mature milk and the concomitant occurrence of a precursor-product relationship between the linoleate and its long-chain PUFA are consistent with the mobilization of a preformed long-chain PUFA pool during early lactation.

Triacylglycerol structure of human colostrum and mature milk

Because triacylglycerol (TAG) structure influences the metabolic fate of its component fatty acids, we have examined human colostrum and mature milk TAG with particular attention to the location of the very long chain polyunsaturated fatty acid on the glycerol backbone. The analysis was based on the formation of various diacylglycerol species from human milk TAG upon chemical (Grignard degradation) or enzymatic degradation. The structure of the TAG was subsequently deduced from data obtained by gas chromatographic analysis of the fatty acid methyl esters in the diacylglycerol subfractions. The highly specific TAG structure observed was identical in mature milk and colostrum. The three major fatty acids (oleic, palmitic and linoleic acids) each showed a specific preference for a particular position within milk TAG: oleic acid for the sn-1 position, palmitic acid for the sn-2 position and linoleic acid for the sn-3 position. Linoleic and alpha-linolenic acids exhibited the same pattern of distribution and they were both found primarily in the sn-3 (50%) and sn-1 (30%) positions. Their longer chain analogs, arachidonic and docosahexaenoic acids, were located in the sn-2 and sn-3 positions. These results show that polyunsaturated fatty acids are distributed within the TAG molecule of human milk in a highly specific fashion, and that in the first month of lactation the maturation of the mammary gland does not affect the milk TAG structure.

Prognostic significance of tumor phosphatidylcholine stearic acid level in breast carcinoma

The involvement of lipid enzymes in the action of oncogenes at the cell membrane level has suggested that membrane lipids could play a role in modulating the growth of tumors. We previously found that breast cancer patients with a low level of polyunsaturated fatty acids in their primary tumor's phosphatidylethanolamine had a high risk of early occurrence of visceral metastasis. In the present study, we prospectively examined whether fatty acid composition of tumor membrane phosphatidylcholine had a prognostic significance in a series of 63 patients with a localized presentation of breast cancer. Membrane phospholipids were extracted from the carcinoma tissue obtained at the time of surgery, phosphatidylcholine was purified, and its fatty acids were analyzed by capillary gas chromatography. During the follow-up period, 20 patients developed metastasis. In these patients, the proportion of stearic acid containing phosphatidylcholine was significantly lower than it was in the tumors of the 43 patients who remained metastasis-free. Multivariate analysis according to Cox showed that low stearic acid level in tumor phosphatidylcholine and high mitotic index were independently predictive of subsequent metastasis. The predictive value of stearic acid level on metastasis risk was higher in node-positive patients than in node-negative patients, allowing individualization of a subgroup of low stearic acid level, node-positive patients with very poor prognosis. We concluded that stearic acid level in tumor membrane phosphatidylcholine is an independent intra-tumor marker of breast cancer prognosis. This finding is new evidence that tumor's structural lipids are linked to the growth of breast cancer.

Fatty-acid composition of breast and iliac adipose tissue in breast-cancer patients

In order to determine to what extent the fatty-acid composition of breast adipose tissue is representative of the body-fat composition in breast carcinoma, we compared the fatty-acid composition of breast adipose tissue to that of iliac fat in breast-cancer patients. Triglycerides from the 2 sites were purified by thin-layer chromatography and fatty-acid composition was determined by capillary gas chromatography. Compared with iliac fat, mammary fat was higher in saturated (33.2 +/- 3.9 vs. 24.4 +/- 1.6%; p = 0.0001) and lower in mono-unsaturated (48.0 +/- 2.2 vs. 54.8 +/- 2.7%; p = 0.0001) and poly-unsaturated fatty acids (16.6 +/- 3.7 vs. 18.0 +/- 3.1%; p = 0.0001). A positive correlation was found between the 2 sites for linoleate (r = 0.95; p = 0.0003), alpha-linolenate (r = 0.83; p = 0.01), palmitate (r = 0.78; p = 0.02) and palmitoleate (r = 0.76; p = 0.02). No relationship was observed for stearic and oleic acids. We conclude that breast and iliac fat differ with regard to fatty-acid composition. The interpretation of fatty-acid composition of the body stores in breast-cancer patients, as an indicator of long-term intake of dietary fat, should take into account the sampling site of stored lipids.

Age-related insulin resistance: a review

Impaired glucose tolerance occurs with age. This impairment is multifactorial including a decrease in insulin-mediated glucose uptake by peripheral tissues and a delay in insulin-induced suppression of hepatic glucose output. A post-binding defect in insulin action such as a reduced capacity to transcribe more glucose transporter mRNA and/or a reduced translocation of preformed glucose transporters to plasma membrane is incriminated. However, insulin resistance with age is not a constant finding and other mechanism(s) has (have) to be involved in old individuals with impaired glucose tolerance and normal tissue insulin sensitivity.

Essential fatty acid composition of human colostrum triglycerides: its relationship with adipose tissue composition

The relationships between essential fatty acid (EFA) composition of colostrum and white adipose tissue (WAT) were examined on day 5 after delivery in 69 healthy women. Fatty acid composition was assessed by capillary gas chromatography, and 33 fatty acids were detected in colostrum and in WAT. Total polyunsaturated fatty acid (PUFA) content was similar in colostrum and in WAT (15.7 +/- 3.1% and 16.1 +/- 3.8%, respectively), but long-chain PUFA content was higher in colostrum than in WAT (2.9 +/- 0.6% and 1 +/- 0.2%, respectively; P less than 0.001). The concentrations of linoleic acid were significantly correlated between colostrum and WAT (r = 0.77, P less than 0.0001). No correlation was found for alpha-linolenic acid. The relationships between long-chain PUFA composition of colostrum and WAT suggested that individual factors along with tissue specificity of the mammary gland are involved in either the capacity of desaturating and chain-elongating pathways and/or incorporation of long-chain PUFAs into colostrum.

Lactose and cataract in humans: a review

In this review, the relationship between lactose and human cataract is examined from the presently available biochemical, metabolic, and epidemiological data. The exceptional cases of homozygous enzyme deficiency being excluded, fragmentary data give reason to believe that a risk of cataract secondary to lactose and galactose ingestion is present in certain subpopulations. In these population groups, the size of which is unknown, the lens could be exposed to intermittent episodes of hypergalactosemia due to the presence of a partial enzyme deficiency in the galactose metabolic pathway, and/or the persistence of a high adult jejunal lactase activity, and/or to a large and repeated consumption of either whole lactose or easily absorbed lactose (hydrolyzed forms and nonpasteurized yogurt).