bluuebunny/crossref_metadata_2025 huggingface dataset:
Dietarily-induced changes in voluntary ethanol consumption and ethanol metabolism in the rat
Authors: Pekkanen Leena , Eriksson K. , Sihvonen Marja-Liisa
Published: May 2005

1. The voluntary ethanol consumption, ethanol elimination rate and blood acetaldehyde level after intraperitoneal injection of ethanol were studied in rats receiving diets with highly imbalanced proportions of dietary protein, carbohydrate and fat.

2. The rats, which received the low-protein diet containing 0.05 of the total energy as protein, 0.80 as carbohydrate and 0.15 as fat, drank only approximately half as much ethanol as did the control group, which received 0.30 of its total food energy from protein, 0.55 from carbohydrate and 0.15 from fat. Ethanol elimination rate in the low-protein group was decreased and the blood acetaldehyde level after ethanol injection was markedly increased.

3. On the high-fat diet, which contained 0.30 of the total energy from protein, 0.05 from carbohydrate and 0.65 from fat, the rats drank significantly more ethanol than did the rats on the control diet; their ethanol elimination rate was decreased but their blood acetaldehyde level was not affected.

4. In conclusion, the strong decrease in voluntary ethanol drinking by the low-protein group may have been caused by the increased acetaldehyde accumulation in the blood, but a particularly low blood acetaldehyde level was not one of the factors inducing excessive ethanol drinking in the high-fat group.
The estimation of whole-body zinc and Zn turnover in rheumatoid and osteoarthritis using65Zn tracer
Authors: Kennedy A. C. , Bessent R. G. , Davis P. , Reynolds P. M. G.
Published: May 2005

1. A method of estimating whole-body zinc, and Zn balances using a two-compartment model in combination with whole-body counting of65Zn, is described. The method is applied to patients with rheumatoid and osteoarthritis.

2. The results suggested that there was not a wide variation in whole-body Zn and Zn turnover in individuals with these two diseases and no clearcut difference between patients with one or the other.
Studies on lipid digestion in the preruminant calf
Authors: Edwards-Webb J. D. , Thompson S. Y.
Published: May 2005

1. The lipolysis of cow's milk fat by salivary lipase (EC3.1.1.3) in the preruminant calf has been studied in vitro by a simulated abomasal digestion, and also in vivo by examining the abomasal effluent collected over 12 h after giving whole milk to a calf.

2. In the in vitro experiment the liquid drained from the clot contained a higher proportion of short-chain fatty acids than the abomasal effluent in the in vivo experiment. This was considered to indicate the absorption of short-chain free fatty acids from within the abomasum.

3. Preferential release of short-chain fatty acids both in vitro and in vivo was observed.

4. The outflow of butyric acid from the abomasum of the calf was initially rapid, but had levelled off at approximately 6 h, whereas the outflow of a typical long-chain fatty acid (palmitic) was fairly constant over the 12 h.

Butyric acid predominated in the free fatty acids of abomasal effluent 0.5 h after feeding (668 mmol/mol total free fatty acids) but had become a minor component by 12 h (15 mmol/mol total free fatty acids).

5. The mean amounts of free and esterified fatty acids (mmol/mol fatty acid ingested) present in the abomasal effluent from the 12 h collection period were: triglyceride 465, diglyceride 215, monoglyceride 68, free fatty acid 252. These values showed that only one-third of esterified fatty acids ingested are lipolysed to absorbable products by salivary lipase.
Lysosomal stability, superoxide dismutase and zinc deficiency in regenerating rat liver
Authors: Dreosti I. E. , Record I. R.
Published: May 2005

1. Lysosomal stability was slightly increased in regenerating livers from rats receiving a zinc-deficient (< 0.5 mg/kg) diet for 10 d before surgery.

2. The activity of superoxide dismutase (EC1.15.1.1) was significantly reduced in the same tissues.

3. The results do not support the view that increased lysosomal fragility represents a major biochemical consequence of nutritional Zn deficiency in animals.
Retention of fluoride from diets containing materials produced during aluminium smelting
Authors: Wright D. A. , Thompson A.
Published: May 2005

1. Using male rats, the availability of fluoride from five by products of the aluminium smelting industry was tested. This was done by considering the balance between fluoride administered in controlled diets and the total fluoride content of waste products eliminated over an experimental period of 1 week.

2. Results indicated that yields of available fluoride expressed as percentage weight of original material were cryolite (Na3ALF8), 45.9%; sodium fluoride (NaF), 41.7%; aluminium fluoride (ALF3.H2O), 9.1%; mist eliminator grid solids (with CaF2), 9.4%; reclaimed alumina with adsorbed F, 0.27%.

3. Of the various tissues analysed for fluoride content, only the kidney and femur showed any significant correlation with the amounts of fluoride absorbed or retained.
Transfer of urea from the blood to the rumen of sheep
Authors: Kennedy P. M. , Milligan L. P.
Published: May 2005

1. The rate of transfer of plasma urea-nitrogen to rumen ammonia was measured by infusion of 15NH4Cl and [15N]urea into sheep given brome grass (Bromus inermis) or lucerne (Medicago sativa) pellets. Urea was infused into the rumen or abomasum of two sheep given brome grass in order to increase the concentration of rumen ammonia.

2. From 6.2 to 9.8 g/d of plasma urea-N were transferred to the rumen of sheep given brome grass pellets and a measurement of 1.3 g nitrogen/d was obtained for a sheep given lucerne pellets. When urea was infused into the rumen of sheep given brome grass pellets the transfer was only 2.8–3.7 g N/d.

3. There was a significant negative correlation between the rate of transfer of plasma urea-N to the rumen and the concentration of rumen ammonia.
The in vitro metabolism of 25-hydroxycholecalciferol by pig kidney: effect of low dietary levels of calcium and phosphorus
Authors: Sommerville Barbara A. , Fox J. , Care A. D. , Swaminathan R.
Published: May 2005

1. Homogenates of pig kidney incubated in vitro convert 25-hydroxycholecalciferol to the dihydroxy-metabolites almost as efficiently as homogenates of chick kidney under similar conditions.

2. The cortex of the kidney carries out this conversion more efficiently than does the medulla.

3. Kidneys from pigs given low calcium or low phosphorus diets produce about 40 % more 1,25-dihydroxy cholecalciferol than those from pigs given diets containing normal levels of Ca and P.
The effects of defaunation of the rumen on the growth of cattle on low-protein high-energy diets
Authors: Bird S. H. , Leng R. A.
Published: May 2005

1. The effects of defaunation of the rumen of cattle on low-protein diets was studied using animals given free access to a basal diet of liquid molasses and 1500 g oaten straw/head per d. These diets induced moderate numbers of protozoa in the rumen.

2. Nonyl phenol ethoxylate (trade name teric GN9) was used for defaunation; 100 g teric GN9 was found to be sufficient to eliminate protozoa from the rumen.

3. In cattle given the basal diet without bypass protein supplementation, defaunation had no effect on growth rates. Addition of 240 g of a feed pellet containing bypass protein increased growth rate significantly. Growth rates were significantly increased by 43 % in cattle on the higher protein intake and where protozoa were removed. Intake of molasses was apparently stimulated by a protein supplementation but not by defaunation and this finding is discussed.

4. The results demonstrate that in cattle given a molasses-based diet, low in bypass protein, growth rates can be stimulated by defaunation without an effect on feed intake, the main effect apparently arising through an increased efficiency of utilization of feed.
Effect of undernutrition on the metabolism of phospholipids and gangliosides in developing rat brain
Authors: Reddy P. V. , Sastry P. S.
Published: May 2005

1. Phospholipid content of brains of 3- or 8-week-old undernourished rats was 7–9 % less than that for the corresponding control animals and this deficit could not be made up by rehabilitation. Phosphatidyl ethanolamine and plasmalogen were the components most affected in brains of undernourished rats.

2. Incorporation of32P into phospholipids by brain homogenates was 28% higher in 3-week-old undernourished rats. It is suggested that enhanced phospholipid metabolism in undernourished animals may be related to behavioural alterations noted previously (Sobotka, Cook & Brodie, 1974).

3. Ganglioside concentrations in 3- and 8-week-old undernourished animals were 14% and 11.5% less respectively than those of the control animals and this difference could be made up by rehabilitation. [14C]Glucosamine incorporation in vivo into brain gangliosides was not affected by undernutrition.
The effects of plane of nutrition and environmental temperature on the energy metabolism of the growing pig
Authors: Close W. H. , Mount L. E.
Published: May 2005

1. The heat losses and energy balances of thirty-eight individually housed pigs (initial body-weights 21–38 kg) were measured continuously for periods of 14 d when they were maintained at environmental temperatures of 10, 15, 20, 25 or 30°. At each temperature four levels of feeding were given approximating to once, twice and three times the maintenance energy intake and the ad lib. level. The minimal maintenance energy requirement (M) was calculated to be 440 kJ metabolizable energy (me)/kg0.75 per d at 25°.

2. me intake at the ad lib. level decreased from 1965 kJ/kg0.75 per d at 10° to 1202 at 30°.

3. Heat loss calculated from multiple regression analysis decreased to minimum levels between 20 and 25° 30° was within the hyperthermic zone at each plane of nutrition.

4. The partition of heat loss into its sensible and evaporative components showed that evaporation increased from 25% at 10° to 78% at 30°.

5. Critical temperature was dependent upon food intake and decreased from 23.1° at M to 20.7° at 2M, 18.0° at 3M and 16.7° at 4M.

6. The extra food required to meet extra thermoregulatory heat production per 1° below the effective critical temperature was 0.65 g/kg body-weight per d.
The effects of plane of nutrition and environmental temperature on the energy metabolism of the growing pig
Authors: Close W. H.
Published: May 2005

1. From the relation between metabolizable energy (me) intake and heat loss (H), energy retention (ER), protein (P) and fat (F) deposition the energy costs of maintenance (MEm) and the partial efficiencies of energy retention (k) and protein (kp) and fat (kf) retention were determined in growing pigs at environmental temperatures of 10, 15, 20, 25 or 30°.

2. k decreased with increase in environmental temperature from 0.79 at 10° to 0.63 at 30° with 0.67 at the thermally-neutral temperature of 25°. Each 0.04 decrease in k was associated with a 100 kJ/kg0.75 per d decrease in mem Analysis, within several ranges of environmental temperature, suggested a curvilinear relation between ER and me intake indicating a decrease in k with increase in level of feeding, particularly at thermally-neutral temperatures.

3. Both kp and kf were similar at each environmental temperature and decreased from 0.78 at 10° to 0.63 at 30°. These values are discussed in relation to those predicted from experimentation and it is suggested that the wide range of predicted estimates of kp could be attributed to differences in the rate of protein turnover.
Serum albumin level in an urban Nigerian population
Authors: Adewoye H. O. , Fawibe J. F.
Published: May 2005

1. Serum albumin levels have been estimated in healthy adult Nigerians. The average level of albumin was 41.4 g/l and there was no sex difference, but the findings differed from that of a previous survey in Ibadan. The importance of serum albumin measurement in relation to the socio-economic and dietary habits of the population has been reviewed.

2. It is concluded that socio-economic, dietary and cultural changes associated with Western education could be responsible for the increased level of serum albumin in this healthy population.

3. It is suggested that similar surveys should be done by locally-practising chemical pathologists.
Growth and liver enzyme response in growing rats to graded levels of methionine and cystine in fortified-barley diets: Response at constant cystine concentration in the diet
Authors: Ngwira T. N. , Beames R. M.
Published: May 2005

1. Thirty-six male rats of initial age 27 d were fed on diets based on barley grain for 3 weeks. Crude protein (nitrogen × 6.25) was fixed at 120.0 g/kg dry matter (dm) and cystine at 2.0 g/kg dm in all diets. The basal diet contained 3.5 g methionine plus cystine/kg dm with l-methionine added in increments of 0.5 g/kg dm up to a final level of 7.0 g methionine plus cystine/kg dm. A ‘positive control’ diet of barley plus 193.7 g soya-bean meal/kg dm contained 6.0 g methionine plus cystine/kg dm.

2. Weight gain, food conversion efficiency (FCE), urinary urea-N excretion, carcass composition and activities of liver cystathionine synthase (EC 4.2.1.22) and N5-methyltetrahydrofolate-homocysteine-methyltransferase (EC 2.1.1.13) were determined.

3. Weight gain, FCE and urinary urea-N excretion indicated that levels of 3.5 and 4.0 g methionine plus cystine/kg dm were inadequate for optimal growth of the rats. These variables indicated 4.7 g/kg dm to be the requirement for methionine plus cystine. Carcass composition results gave no clear indication of optimal requirements for methionine plus cystine.

4. Cystathionine synthase and N5-methyltetrahydrofolate-homocysteine-methyltransferase activities (/mg protein per 60 min) were constant at 24.32 μmol and 0.64 μmol respectively, when methionine plus cystine level was between 3.5 and 5.0 g/kg dm. Cystathionine synthase was then inhibited at the 6.0 g/kg dm level to a minimum activity of 16.12 μmol/mg protein per 60 min, whereas activity of the re-methylation enzyme increased to a maximum level of 2.92 μmol/mg protein per 60 min at the 6.0 g/kg dm level of methionine plus cystine. At the levels of methionine plus cystine above 6.0 g/kg dm cystathionine synthase activity increased while the activity of N5-methyltetrahydrofolate-homocysteine-methyltransferase decreased.
Plasma alkaline ribonuclease (EC 3.1.4.22) and nitrogen retention in low-birth-weight infants
Authors: Scott P. H. , Berger H. M. , Kenward Caroline , Scott P. , Wharton B. A.
Published: May 2005

1. Nitrogen retention was determined by classical N balance techniques in fourteen rapidly growing low-birth-weight infants receiving 3 g protein/kg body-weight and during their 3rd week of life. This was compared with plasma free alkaline ribonuclease (EC3.1.4.22; RNase) activity and other biochemical measurements of protein nutrition.

2. Plasma RNase showed a significant positive correlation with N retention and a corresponding negative correlation with urine urea-N. These results were unexpected and suggest a different relationship between RNase and N retention in infants compared with that found by other workers in children and adults.

3. The most likely explanation of this apparent anomaly is that in all instances high activities of plasma RNase are associated with a need to conserve N. In the infants studied this may indicate some measure of ‘protein economy’ and they could therefore benefit from a higher protein intake.
The effect of the extent of hydrolysis in casein on its specific dynamic action in the rat
Authors: Gawęcki J. , Jeszka J.
Published: May 2005

1. Adult female rats given a diet containing 200 g casein/kg showed an increase in heat production which reached a maximum in 10–20 min after completion of food intake.

2. Replacement of casein in the diet by enzymic hydrolysates of casein of different extents of hydrolysis (pepsin for 1 or 3 h and pancreatin for 6, 12 or 24 h) resulted in a decrease in metabolic rate (stimulation) in the rat, reaching a maximum of 61.8% of the control value (non-hydrolysed casein).

3. The specific dynamic action of casein and casein hydrolysate was inversely proportional to the amount of amino-nitrogen released.

4. On the basis of the experimental findings it may be concluded that the synthesis and secretion of digestive enzymes were the main causes of the increase in metabolic rate after protein ingestion.
Studies on the absorption of calcium, phosphorus, magnesium, copper and zinc by sheep fed on roughage-cereal diets
Authors: Stevenson M. Hilary , Unsworth E. F.
Published: May 2005

1. Two groups of four 18-month-old ewes fitted with a rumen cannula and re-entrant cannulas in the proximal duodenum were fed on one of two diets based on varying proportions of dried-grass meal, ground straw and barley.

2. The apparent availability, retention and amount of the mineral reaching the proximal duodenum were measured for calcium, phosphorus, magnesium, copper and zinc. Significant differences were found between diets for Ca only. Net absorption of Mg occurred before the proximal duodenum and also, lower down the alimentary tract. Marked increases were observed in the amount of Cu, Zn and P reaching the proximal duodenum relative to that ingested.
Generalized equations for predicting body density of men
Authors: Jackson A. S. , Pollock M. L.
Published: May 2005

1. Skinfold thickness, body circumferences and body density were measured in samples of 308 and ninety-five adult men ranging in age from 18 to 61 years.

2. Using the sample of 308 men, multiple regression equations were calculated to estimate body density using either the quadratic or log form of the sum of skinfolds, in combination with age, waist and forearm circumference.

3. The multiple correlations for the equations exceeded 0.90 with standard errors of approximately ±0.0073 g/ml.

4. The regression equations were cross validated on the second sample of ninety-five men. The correlations between predicted and laboratory-determined body density exceeded 0.90 with standard errors of approximately 0.0077 g/ml.

5. The regression equations were shown to be valid for adult men varying in age and fatness.
The effect of dietary protein intake on calcium metabolism of the pregnant ewe
Authors: Braithwaite G. D.
Published: May 2005

1. The effect of protein intake on calcium metabolism has been studied in the pregnant ewe.

2. Results suggest that decreased Ca retention in protein-deficient animals was a result of a decreased rate of Ca absorption and not a decreased rate of bone accretion as suggested by other workers.
Absorption of inorganic ions and volatile fatty acids in the rabbit caecum
Authors: Leng Elke
Published: May 2005

1. Rabbit caecal segments in situ were used to measure absorption rates of volatile fatty acids (VFA) and inorganic ions from a saline solution comparable in composition to normal caecal fluid.

2. Results confirm the importance of VFA absorption from caecal material found by other workers.

3. Like the mammalian colon, the rabbit caecum conserved large amounts of sodium, chloride and water. Bicarbonate was also absorbed.

4. VFA replacement studies showed that net water absorption was reduced, net electrolyte absorption was hardly influenced.

5. Na replacement completely inhibited net water absorption and decreased net VFA and Cl absorption, HCO3was heavily secreted.

6. These findings indicate that VFA absorption in the rabbit caecum is partly dependent on Na absorption and that in the absence of Na an anion-exchange mechanism occurs.
Effect of Vitamin B12deficiency on phosphatidylethanolamine methylation in rat liver
Authors: Åkesson B. , Fehling C. , JÄGerstad Margaretha
Published: May 2005

1. In vitamin B12deficiency the activity of tetrahydropteroylglutamate methyltransferase (EC2.1.1.13) is depressed and the synthesis of methionine is reduced. Because the methyl group of methionine is largely utilized for the methylation of phosphatidylethanolamine, we investigated the effects of vitamin B12deficiency on phosphatidylcholine synthesis.

2. The incorporation of injected [14Clformaldehyde into liver phosphatidylcholine was reduced by approximately 50% in vitamin B12-deficient rats. Also the corresponding incorporation of 5-[14C]methyl-tetrahydrofolic acid tended to decrease. The findings are consistent with a lower conversion of these precursors to methionine.

3. The effect of the deficient methyl-group supply on phosphatidylcholine synthesis was also investigated by the injection of [14C]ethanolamine. The amount (%) of lipid-14C recovered in phosphatidylcholine was significantly reduced in vitamin B12deficiency.

4. Chemical analysis of liver phospholipids showed that the vitamin B12-deficient rats had a higher proportion of phosphatidylethanolamine and a lower proportion of phosphatidylcholine, indicating that the impaired synthesis of phosphatidylcholine by methylation leads to changes in membrane phospholipid composition.
The effects of folic acid supplementation during pregnancy in the rat
Authors: Morgan B. L. G. , Winick M.
Published: May 2005

1. Twenty-four Sprague-Dawley female rats were randomly assigned to three groups (groups A, B, C). Group A was given a folic acid-free diet and groups B and C received 0.0018 g folic acid/kg diet. Rats in group C were also given a supplement of 1 mg folic acid/d by intraperitoneal injection.

2. After 14 d of feeding the rats were mated. The diets were continued throughout gestation. On day 21, of gestation the dams were killed and their livers and products of conception assayed for RNA, DNA, protein and tetrahydrofolate dehydrogenase (5,6,7,8-tetrahydrofolate dehydrogenase;EC1.5.1.3) activity.

3. The foetuses, placentas and livers from supplemented rats (group C) were significantly larger than those from groups A and B and had a higher content of RNA, DNA and protein. Those tissues from group A dams were smaller than those from the other groups and had a correspondingly reduced nucleic acid and protein content.

4. The activity of tetrahydrofolate dehydrogenase, the first and rate-limiting enzyme in the metabolism of folate, was increased in the folate supplemented rats (group C) and reduced in the rats given a folic acid-free diet (group A). These changes in enzyme activity could explain the differences in nucleic acid biosynthesis and growth shown by the different groups.
Immune response in rats given irradiated wheat
Authors: Vijayalaxmi
Published: May 2005

1. Rats given diets containing freshly-irradiated wheat showed significantly lower mean antibody titres to four different antigens, decreased numbers of antibody-forming cells in the spleen and rosette-forming lymphocytes as compared to rats given either unirradiated wheat or irradiated wheat stored for a period of 12 weeks.

2. The immune response in rats given 90 g protein/kg diet was essentially similar to that seen in animals given 180 g protein/kg diet.
Concurrent studies of the flow of digesta in the duodenum and of exocrine pancreatic secretion in calves
Authors: Ternouth J. H. , Roy J. H. B.
Published: May 2005

1. The effects of bucket- v. teat-feeding and warm- v. cold-milk feeding on the flow of duodenal digesta and the concurrent pancreatic secretion were studied in two experiments in preruminant Ayrshire calves (28–43 d of age), fitted with duodenal re-entrant and pancreatic sac cannulas.

2. As measured by the time interval taken for total recovery of the polyethylene glycol fed in the milk, the whey fluids had a more rapid passage through the abomasum when the calves were given warm milk by teat rather than by bucket (Expts 1 and 2). The duodenal digesta contained less sodium ions and more ‘Cl-Na+’ when the calves were fed by teat even though the volumes of milk drunk and duodenal flow were similar. It was concluded that more abomasal acid was secreted when calves were fed by teat.

3. When the calves were fed by teat rather than by bucket, the protein-nitrogen : N (PN : N) in the duodenal digesta was lower, especially during the first 6 h after feeding and there was a tendency for more pancreatic proteases to be secreted.

4. In Expt 1, when the calves were given warm milk the total flow of N and lipid in the duodenal digesta was 22 and 19% greater than that ingested. This was considered to be due to the coagulum from the penultimate meal plus the experimental meal passing more readily through the duodenum when sampling and to endogenous secretion of N and lipid.

5. When four Ayrshire calves were bucket-fed cold, rather than warm milk there was a reduced secretion of abomasal and pancreatic fluids and abomasal acid. There were no differences in the time interval required for the whey fluids to leave the abomasum or the PN : N value.

6. There was a positive correlation between the total duodenal flow of non-whey fluids and the pancreatic secretion regardless of the method of feeding.

7. The completeness of digestion and susceptibility of calves to diarrhoea when fed by teat and bucket is discussed.
The effect of trenbolone acetate with time on the various responses of protein synthesis of the rat
Authors: Vernon B. G. , Buttery P. J.
Published: May 2005

1. The anabolic agent trenbolone acetate (3-oxo-17 β-hydroxy-4,9, 11-oestratriene acetate; TBA) given subcutaneously to female rats increased their growth rate compared with that of the placebo-treated controls.

2. The increased growth rate of the TBA-treated rats was not a consequence of an increased water retention. The TBA-treated rats had a significantly higher (P< 0.01) total carcass nitrogen content but the total carcass fat content decreased by a non-significant (P> 0.05) 8.3%.

3. There was evidence of a time-lag in the response of the fractional synthetic rate of certain individual tissues to TBA. The fractional synthetic rates of the uterus and skeletal muscle mixed tissue proteins were significantly reduced in the TBA-treated rats.

4. The measured reduction in fractional synthetic rates was concluded to reflect true changes in the synthetic rate rather than a result of an alteration in the specific activity of the tyrosine pool used for protein synthesis.
The effects of fasting in Ramadan
Authors: Gumaa K. A. , Mustafa K. Y. , Mahmoud N. A. , Gader A. M. A.
Published: May 2005

1. The changes in serum levels of uric acid and lipids during 1 month of starvation-refeeding were measured in sixteen male volunteers.

2. Uric acid levels increased linearly with the duration of the experiment. The increase was positively correlated with the increase in serum triglycerides but not with cholesterol or phospholipids.

3. Triglycerides increased at a faster rate than uric acid implying that the increase in uric acid was secondary to that of the lipid.

4. It was concluded that the purine and lipid synthetic pathways are linked through a common small-molecular-weight effector rather than through the sharing of a common enzyme.
The effects of fasting in Ramadan
Authors: Mustafa K. Y. , Mahmoud N. A. , Gumaa K. A. , Gader A. M. A.
Published: May 2005

1. Fluid intake, urine output and evaporative water loss were measured and fluid balance calculated in sixteen subjects for 1 d before Ramadan, during weeks 1–5 of fasting and on the 10th day after the end of Ramadan.

2. Plasma osmolality at 06.00 hours, the beginning of the fast, at 18.00 hours, before breaking the fast and at 19.00 hours, 1 h after breaking the fast, and urine osmolality during the day and night were measured before, during and after Ramadan.

3. All subjects developed an initial negative fluid balance which was maximum at the beginning of week 3 of fasting and that deficit was compensated for during the later weeks.

4. Compensation was brought about by an increase in urine concentration, a decrease in urine volume by day, and salt retention.

5. No significant changes were observed in plasma osmolality during the days of fasting and the ‘setting’ of plasma osmolality during Ramadan also was not changed.

6. It was concluded that healthy young adults maintain good control of fluid and electroytes during Ramadan.
Effect of water-soluble oxalates in Amaranthus spp. leaves on the absorption of milk calcium
Authors: Pingle Urmila , Ramasastri B. V.
Published: May 2005

1. Amaranthus spp. leaves contain high amounts of oxalates which affect the calcium absorption. This study was done to determine whether removal of the water-soluble oxalates from the leaves by cooking would reduce this deleterious effect.

2. Experimental work done with two types of basal diets on six adult male subjects has shown that the milk Ca absorption was low when leaves cooked without draining away the water were included in the diet. However when the soluble oxalates were removed by throwing away the water after cooking the leaves, the absorption of milk Ca was unaffected.
Biochemical aspects of malabsorption in marasmus
Authors: Mehta H. C. , Saini A. S. , Singh Harjit , Dhatt P. S.
Published: May 2005

1. Sixty marasmic children and fifteen normal age-matched controls were investigated for the absorption of fats and proteins. Their duodenal juice samples were also analysed for bile salts and microflora.

2. A significant amount of malabsorption, with respect to both the dietary ingredients, was observed in the majority of the marasmic children.

3. The levels of conjugated bile acids in the duodenal juice samples of marasmic children were significantly lower as compared with those of normal controls, while the reverse was true for free bile acids and bacterial counts.

4. Significant correlations were observed between bile acid levels and fat absorption and also between microflora and free bile acids.

5. The pathophysiology of malabsorption in marasmus is discussed in the light of these findings.
Maternal adipose tissue response to nicotine administration in the pregnant rat: effects on fetal body fat and cellularity
Authors: Williams Christine M. , Kanagasabai Tazeen
Published: May 2005

1. Nicotine has been implicated as a causative factor in the intrauterine growth retardation associated with smoking in pregnancy. A study was set up to ascertain the effect of nicotine on fetal growth and whether this could be related to the actions of this drug on maternal adipose tissue metabolism.

2. Sprague-Dawley rats were mated and assigned to control and nicotine groups, the latter receiving nicotine in the drinking-water throughout pregnancy. Animals were weighed at regular intervals and killed on day 20 of pregnancy. Rates of maternal adipose tissue lipolysis and lipogenesis were measured. Fetal and placental weights were recorded and analysis of fetal body water, fat, protein and DNA carried out.

3. Weight gains of mothers in the nicotine group were less in the 1st and 2nd weeks of pregnancy, but similar to controls in the 3rd week. Fetal body-weights, DNA, protein and percentage water contents were similar in both groups. Mean fetal body fat (g/kg) was significantly higher in the nicotine group (96.2 (se5.1)) compared with controls (72.0 (se2.9)). Rates of maternal lipolysis were also higher in the nicotine group.

4. The cause of these differences and their effects on maternal and fetal well-being is discussed.
The energy equivalents of ATP and the energy values of food proteins and fats
Authors: Livesey Geoffrey
Published: May 2005

1. Heats of combustion and energy equivalents of cytoplasmic ATP have been estimated for glucose, 101 food proteins and 116 food fats based on amino acid and fatty acid composition data from food composition tables and the heats of combustion and energy equivalents of cytoplasmic ATP of each individual amino acid, fatty acid, glycerol and glucose. The isodynamic equivalents of carbohydrate, fat and protein at the biochemical level have been investigated.

2. Heats of combustion of food proteins and fats derived from compositional data were within 1 % of published values obtained by calorimetry.

3. Cytoplasmic ATP equivalents for glucose, fat and protein range from 9·0 to 14·7, 8·6 to 14·6 and 6·4 to 13·2 mol cytoplasmic ATP/MJ of metabolizable energy respectively, depending on the choice of mitochondrial proton stoichiometries for these estimations. The range is extended further when considering the level and type of mitochondrial ‘uncoupling’.

4. Isobioenergetic relationships between the efficiencies of glucose (G) and fat (F) (F= 1·05 G-0·9) and glucose and protein (P) (P=G(1·02–0·19f)-(1.8+0·5f)) energy conversions (wherefis the fraction of protein oxidized via gluconeogenesis) were obtained and were essentially independent of the choice of mitochondrial proton stoichiometry and the level and type of uncoupling of oxidative phosphorylation.

5. Potential errors in previous estimates of ATP yield from protein are shown to be as much as -17·6 to < 118%; accounting for the efficiency of mitochondrial oxidative phosphorylation narrows this to between -7·9 and 17·4% and accounting for the fraction of protein oxidized via gluconeogenesis limits this further to between - 7·9 and 11·1%. Remaining uncertainty is attributed mostly to lack of knowledge about the energy cost of substrate absorption from the gut and transport across cell membranes.

6. Coefficients of variation (cv) in the cytoplasmic ATP yield/g protein and /g protein nitrogen for the 101 food proteins were large (0·033 and 0·058 respectively). This is attributed mostly to variation in the metabolizable heats of combustion (cv 0·033 and 0·053 respectively) and to a much smaller extent in the efficiency with which cytoplasmic ATP equivalents are generated/MJ of metabolizable energy (cv 0·01).

7. It is concluded that the current understanding of biochemical energy transduction is sufficient to permit only a crude estimate of the energy equivalents of cytoplasmic ATP but that these equivalents vary by less than 5% between both different food proteins and different food fats. Isobioenergetic equivalents for carbohydrates, fats and protein which could be applied to modify the Atwater conversion factors are possible but require first an accurate quantification of the energy equivalent of cytoplasmic ATP for glucose in vivo, and an indication that oxidative phosphorylation is similarly efficient in different individuals.
Reduction in the antigenicity of whey proteins by heat treatment: a possible strategy for producing a hypoallergenic infant milk formula
Authors: Heppell L. M. J. , Cant A. J. , Kilshaw P. J.
Published: May 2005

1. Residual antigenic protein in heat-denatured cow's milk whey and in two commercial infant milk formulas was determined using enzyme-linked immunosorbent assays specific for β-lactoglobulin, α-lactalbumin, bovine serum albumin, bovine IgG1and α-casein. This immunochemical assessment of antigenicity was related to the capacity of the preparations to sensitize immunologically when fed to guinea-pigs for 2 weeks. Antibody production was measured and the susceptibility of the animals to systemic anaphylaxis was assessed by injecting them intravenously with heated or unheated milk proteins.

2. Whey protein that had been heated at 100° or 115° for 30 min was extensively denatured and, in contrast to pasteurized whey, failed to sensitize guinea-pigs for anaphylaxis. Antibody production was undetected or very low. The proteins in SMA powder and SMA Gold Cap liquid concentrate were less denatured and animals given these formulas prepared according to the maker's instructions produced relatively high levels of antibodies to β-lactoglobulin and α-casein and a majority developed anaphylaxis when injected intravenously with these products.

3. As well as failing to sensitize, whey that had received severe heat treatment did not, in most cases, elicit anaphylaxis when injected into animals that had been sensitized with unheated milk.

4. Discrimination between antibodies of the IgG1and IgG2subclasses specific for β-lactoglobulin showed that IgG1, the principal anaphylactic antibody in guinea-pigs, was preferentially depressed in animals drinking heat-denatured milk preparations.

5. The results suggest that heat denaturation of whey protein may be a logical and simple strategy for producing a hypoallergenic baby milk. Nevertheless, the value of experiments in guinea-pigs for predicting results in man is uncertain and the proposal awaits assessment in clinical trials.
Factors affecting the absorption of iron from cereals
Authors: Gillooly M. , Bothwell T. H. , Charlton R. W. , Torrance J. D. , Bezwoda W. R. , MacPhail A. P. , Derman D. P. , Novelli L. , Morrall P. , Mayet F.
Published: May 2005

1. Non-haem-iron absorption from a variety of cereal and fibre meals was measured in parous Indian women, using the erythrocyte utilization of radioactive Fe method.

2. The present study was undertaken to establish whether alteration of the phytate and polyphenol contents of sorghum (Sorghum vulgare) affected Fe absorption from sorghum meals, and to assess the influence of fibre on Fe absorption.

3. Removing the outer layers of sorghum grain by pearling reduced the polyphenol and phytate contents by 96 and 92% respectively. This treatment significantly increased the geometric mean Fe absorption from 0.017 to 0.035 (t 3.9, p < 0.005).

4. The geometric mean Fe absorption from a sorghum cultivar that lacked polyphenols (albino sorghum) was 0.043, which was significantly greater than the 0.019 absorbed from bird-proof sorghum, a cultivar with a high polyphenol content (t 2.83, p < 0.05).

5. Fe was less well absorbed from the phytate-rich pearlings of the albino sorghum than from the pearled albino sorghum (0.015 v. 0.035 (t 8.4, P < 0.0005)). Addition of sodium phytate to a highly Fe-bioavailable broccoli (Brassica oleracea) meal reduced Fe absorption from 0.185 to 0.037.

6. The geometric mean Fe absorption from malted sorghum porridge was 0.024 when 9.5 mg ascorbic acid were added and 0.094 when the ascorbic acid was increased to 50 mg (t 3.33, P < 0.005). This enhancing effect of 50 mg ascorbic acid was significantly depressed to 0.04 by tea (t 38.1, P < 0.0005).

7. Wheat bran significantly decreased the geometric mean Fe absorption from white flour from 0.116 to 0.043 (t 7.2, P < 0.0005).

8. Some of the constituents of the dietary fibre complex, such as apple pectin, guar gum, gum tragacanth and microcrystalline cellulose did not inhibit Fe absorption. On the other hand, hemicellulose and lignin decreased absorption. The geometric mean absorption of Fe given with hemicellulose was 0.079 v. 0.269 with microcrystalline cellulose (t 2.95, P < 0.05). Addition of cocoa, which contains approximately 280 g lignin/kg, reduced the geometric mean Fe absorption from milk from 0.075 to 0.035 (t 2.7, P < 0.05).
A study of the effects of dietary gum arabic in the rat
Authors: McLean Ross Alasdair H. , Eastwood Martin A. , Brydon William G. , Busuttil Anthony , McKay Linda F. , Anderson Douglas M. W.
Published: May 2005

1. Gum arabic (GA) is a water-soluble polysaccharide (molecular weight approximately 850000) containing rhamnose, arabinose, glucuronic acid and galactose.

2. The metabolism of GA has been studied in the rat. Adult male Wistar rats were given GA incorporated into either an Oxoid breeders (OB) diet or an elemental (Elem) diet.

3. Intestinal contents were examined for precipitable GA using acidified ethanol. GA was found from stomach to small intestine but not in the caecum, colon or rectum.

4. Caecal excision and restoration of intestinal continuity resulted in GA recovery from stomach to rectum.

5. Excreted methane, hydrogen and volatile fatty acids (VFA) were measured as indicators of bacterial activity in the caecum and colon. Methane excretion increased on the OB+GA diet and H2 concentrations remained unaltered. The Elem diet abolished gas production. When the animals were given the Elem+GA diet, H2 and methane were only produced after 28 d. Faecal VFA increased with increasing GA intake, acetate concentration increased and butyrate concentration decreased with increasing GA dosage. Significant decreases in concentrations of VFA were found from caecum to left colon and from left colon to faeces.

6. It can be concluded that GA degradation occurs in the caecum and is associated with increased methane excretion, increased VFA concentrations and changes in the proportions of various VFA in the faeces.
A 2-year longitudinal nutritional survey of 405 Northumberland children initially aged 11.5 years
Authors: Hackett A. F. , Rugg-Gunn A. J. , Appleton D. R. , Eastoe J. E. , Jenkins G. N.
Published: May 2005

1. Children (405), initially of average age 11.5 years, recorded all food and drinks consumed for three consecutive days (with an interview on the fourth day) on five separate occasions over a 2-year period. Food tables (Paul & Southgate, 1978) enabled nutrient intakes to be calculated. The data collected were found to be of high reliability (Hackettet al.1983).

2. The mean energy intakes showed broad agreement with other recent British dietary surveys but were well below those recorded in the prewar study by Widdowson (1947) and the FAO/WHO (1973) recommended levels. They were slightly below the current Department of Health and Social Security (DHSS; 1979) recommended intakes.

3. Over the 2-year period, the energy intake of the boys increased by 13% compared with an increase of only 7% in the girls.

4. The iron and vitamin A intakes of all groups of children were low compared with current recommendations (DHSS, 1979). This seems to be a result of falling energy intake. Mean calcium intakes were also only marginally in excess of the recommended intake, and those of most of the girls would fall below the recommendation if the proposal to end the fortification of flour (DHSS, 1981) is implemented.
Availability of lysine in vegetable protein concentrates as determined by the slope-ratio assay with growing pigs and rats and by chemical techniques
Authors: Batterham E. S. , Murison R. D. , Andersen L. M.
Published: May 2005

1. The availability of lysine in nine vegetable-protein concentrates was assessed using the slope-ratio assay for growing pigs and rats. Diets were equalized for crude fibre using solka floc to minimize any possible effects of variation in fibre content on availability estimates.

2. The availability of lysine in the nine proteins for pigs, using food conversion efficiency (FCE) on a carcass basis as the criterion of response were (proportion of total): cottonseed meal 0.39, lupin (Lupinus angustifolius) seed meal no. 10.37, no. 20.65, no. 30.54, no. 40.54, field peas (Pisum sativum) 0.93, peanut (groundnut) meal 0.57, soya-bean meal no. 10.98, no. 2 0.89.

3. Estimates of available lysine for rats as assessed by the slope-ratio assay using FCE on a carcass basis were in close agreement with the pig estimates for cottonseed meal (0.35) and soya-bean meal no. 1(0.91) and no. 2(0.89), higher for lupin-seed meals (range 0.70–0.94 with a mean of 0.81) and peanut meal (0.76) and lower for field peas (0.76).

4. The differences in available lysine were not detected by the chemical Silcock available-lysine test (Roach et al. 1967) or by the direct 1-fluoro-2,4-dinitrobenzene procedure (Carpenter, 1960).
The effect of meal-feeding and food restriction on body composition, food utilization and intestinal adaptation in light-breed chicks
Authors: Nitsan Zafrira , Nir I. , Petihi I.
Published: May 2005

1. The effects of feeding meals, in amounts equivalent to ad lib. intake or to 75% and 50% restriction by intubation, were studied in chicks.

2. Growth estimated by body-weight gain and shank length was improved by tube feeding in the 50%-restricted chicks.

3. Tube feeding increased energy retention at all feeding levels and nitrogen retention in the restricted chicks only.

4. Body fat was increased in the full-fed chicks by intubation and decreased in the 50%-restricted chicks only.

5. Crop and gizzard weights were increased by food restriction and by intubation. Tube-feeding increased the weight of the small intestine at all feeding levels.

6. The activities of the digestive enzymes were lower in the pancreas and higher in the small intestine of the tube-fed chicks than in the voluntarily-fed ones at all feeding levels.

7. It is suggested that synthesis, secretion and stablity of the different pancreatic enzymes could be affected diversely by feeding regimens.
The simultaneous estimation of the amounts of protozoal, bacterial and dietary nitrogen entering the duodenum of steers
Authors: Cockburn J. E. , Williams A. P.
Published: May 2005

1. Four steers were given straw and tapioca diets, twice daily, in a 4 x 4 Latin-square design. These diets, containing 4.2 g nitrogen/kg dry matter (DM), were further supplemented with either urea, decorticated groundnut meal (DCGM), untreated (UT) casein or formaldehyde-treated (FT) casein to give a total of 19.7 g N/kg DM and 10.5 MJ/kg DM daily.

2. Concurrent samples of rumen bacteria and protozoa and abomasal digesta were collected for each period of the experiment and the concentrations of 2-aminoethyl phosphonic acid (AEPA), diaminopimelic acid (DAPA), total nitrogen (TN), total phosphorus (TP), amino acids and hexosamines were determined in the dried preparations. The nature of the dietary supplements had little effect on the concentrations of most of these constituents or on the total protozoal numbers.

3. Abomasal digesta samples marked with polyethylene glycol (PEG) and chromic oxide for flow estimation were collected over 24 h, and the proportions of protozoal-N, bacterial-N and microbial-N estimated simultaneously using the markers AEPA, DAPA and RNA respectively. These digesta-N components were also estimated using an amino acid profiling (AAP) method which gave, in addition, estimates of the dietary and endogenous components. For the diets containing casein, the proportion of dietary casein was estimated directly using casein-P as a marker.

4. Estimates of the respective mean proportions of microbial-N in abomasal digesta non-ammonia-N (NAN) for the diets containing urea, DCGM, UT casein or FT casein were: AEPA 0.56, 0.32, 0.27 and 0.16; DAPA 0.88, 0.70, 0.81 and 0.57; RNA 0.98, 0.85, 0.92 and 0.53.

5. Giving FT casein significantly (P< 0.001) increased the flow of casein-N at the abomasum and a significantly (P< 0.001) greater proportion of casein-N was found in abomasal NAN (0.51v.0.09) where FT rather than UT casein was given.

6. The AAP method gave results for the proportions of microbial- and dietary-N (where casein was given) which were, in general, slightly lower than those obtained using RNA and casein-P as markers. Agreement with estimates of bacterial protein (from DAPA) and of protozoal protein (from AEPA) was less satisfactory.

7. Comparisons of the various estimates of the proportions of microbial-N in abomasal digesta suggested that the results obtained for protozoal-N by AEPA were overestimates. AEPA was found in mixed rumen bacteria which may have accounted in part for these overestimates. However, AEPA was not detected in any of the dietary ingredients.