摘要:

Defatted meals were prepared from two new varieties of rapeseed, the ‘high-glucosinolate’ variety, Brassica napus, Lesira, and the ‘low-glucosinolate’ variety, Brassica napus, Erglu, by each of the following processes: (1) defatting of the ground seed with hexane; (2) extraction of the myrosinase-deactivated ground seed with 70% aqueous acetone for the removal of glucosinolates followed by defatting with pure acetone, and (3) autolysis of the ground seed for the decomposition of glucosinolates followed by defatting and simultaneous removal of the decomposition products with hexane. The defatted meals obtained after extraction with aqueous acetone or autolysis contain very little glucosinolates and their degradation products as compared to those obtained by defatting with hexane only. The contents of available lysine and of phytates in the meals are, to some extent, affected by the treatment for the removal of glucosinolates. The rapeseed meals were fed at different levels to protein-depleted chicks and weanling rats. The animals fed low-glucosinolate meals prepared both from high-glucosinolate and low-glucosinolate varieties of rapeseed gave superior performance with regard to the feed conversion and protein efficiency ratio as compared to the animals fed the corresponding meals which were obtained simply by defatting the seeds with hexane. The levels of thyroxine (T4)and triiodothyronine (T3) in the serum of rats fed low-glucosinolate meals indicated normal function of the thyroid, whereas those in rats fed high-glucosinolate meals revealed hypo-thyroidism of the

ISSN:0250-6807    

DOI:10.1159/000176235

出版商:S. Karger AG    

年代:1979

数据来源: Karger

摘要:

In normal weanling male rats, the intraperitoneal administration of zinc sulphate (ZnSO4) resulted in a decreased hepatic and an increased plasma concentration of vitamin A after 2 h. In an in vitro study, the vitamin A concentrations of liver homogenates were markedly increased when homogenized livers were treated with ZnSO4. ZnSO4, however, did not show any effect on plasma and liver concentrations of vitamin E. These results indicate that zinc may be specifically involved in mobilizing vitamin A from liver to the circulation of normal animals within a short period. The trace element, therefore, could be used not only to treat cases of depressed vitamin A in plasma but also to treat hepatic toxicity from hypervitaminosis A.

ISSN:0250-6807    

DOI:10.1159/000176236

出版商:S. Karger AG    

年代:1979

数据来源: Karger

摘要:

The dose relationship of hemiglobin iron absorption has been investigated in subjects with normal and depleted iron stores and was found to fit a linear regression in a bilogarithmic presentation of hemiglobin iron dose and iron absorption. Identical regression coefficients but different intercepts of regression were estimated for subjects with normal and depleted iron stores indicating a constant proportional increase of hemiglobin iron absorption in subjects with depleted iron stores in the full dose range of 0.10–50 mg hemiglobin iro

ISSN:0250-6807    

DOI:10.1159/000176237

出版商:S. Karger AG    

年代:1979

数据来源: Karger

摘要:

Transcription was determined in liver chromatin from rats fed for 6 days, an optimal (20%) or suboptimal (3%) amount of high-quality protein. Transcription by Escherichia coli RNA polymerase (EC 2.7.7.6) was lower after prolonged incubation with chromatin from rats fed 3% as compared with 20% protein. Differences were detected in the transcripts of the two types of chromatin after analysis by sucrose density gradient centrifugation. But no measurable differences were found in the melting profiles at low ionic strength of the two chromatin preparations. Transcription per milligram chromatin DNA was 25-fold higher using E. coli RNA polymerase instead of rat liver RNA polymerase II. The use of UTP as radioactive precursor in the absence of ATP, GTP and CTP resulted in a low labelling of RNA. One [γ32P]UTP nucleotide was incorporated/8 UMP nucleotides. The product obtained was sensitive to ribonuclease treatment. In the presence of ATP, GTP and CTP [γ-32P]UTP nucleotide incorporation was reduced and that of UMP nucleotide was increased giving a ratio of 1:18

ISSN:0250-6807    

DOI:10.1159/000176238

出版商:S. Karger AG    

年代:1979

数据来源: Karger

摘要:

Nonphosphorylated thiamine was extracted from tissue homogenates in saline or sucrose into ethylbutylketone-acetonitrile using counter-ion extraction and re-extracted into hydrochloric acid. The dried samples were then analyzed by the fluorimetric thiochrome method. Phosphorylated thiamine was treated with Takadiastase to split off the phosphate groups and was thereafter extracted and measured. No column chromatography was needed for the separation of thiamine before the thiochrome assay. A higher accuracy and sensitivity for the thiamine assay was thus achieved.

ISSN:0250-6807    

DOI:10.1159/000176239

出版商:S. Karger AG    

年代:1979

数据来源: Karger

摘要:

Plasma cholesterol esterifying activity has been measured in guinea pigs fed either a control diet or the same diet supplemented with 1% cholesterol. The extent of esterification was found to be similar in the cholesterol-fed and control guinea pigs and somewhat lower than in rats. The initial rate of esterification was also of the same magnitude as that found in rats and humans, and unaffected by dietary cholesterol if autologous plasma was used as substrate. However, LCAT activity from cholesterol-fed guinea pigs was significantly higher than that of control plasma when acting on either control or cholesterol-fed substrate. This suggests that dietary cholesterol increases the amount (or activity) of LCAT but that the substrate is unsuitable or that a necessary cofactor is present in limiting amounts. Heat treatment of guinea pig plasma seems to alter substrate availability to varying degrees. The implications of these findings in relation to substrate specificity and cofactor requirements of guinea pig LCAT are discussed.

ISSN:0250-6807    

DOI:10.1159/000176240

出版商:S. Karger AG    

年代:1979

数据来源: Karger

摘要:

N-acetyl-(14C)neuraminosyl-(α,2→3)lactose enzymatically prepared of CMP-NeuNAc and lactose by a particulate enzyme fraction from lactating rat mammary gland was applied orally to newborn rats and examined for uptake and distribution in relation to those of free N-acetyl-(14C)neuraminic acid. The neonates were allowed to stay with their mother before and during the incubation time up to 6 h. Within this time 70% of the given dose was excreted while 30% was retained in the body. (14C)NeuNAc-lactose activity appeared 1.5 h after application in blood, urine, and tissues and attained maximum values after 3 and 6 h, respectively. The highest uptake occurred in liver, spleen, and brain. The absorption of the trisaccharide was delayed by 30 min compared with free (14C)NeuNAc. The time courses of the curves show a slower but higher accumulation in the tissues suggesting a better utilization of the (14C)NeuNAc from (14C)NeuNAc-lactose or pecularities in the absorption of the trisaccharide by the orga

ISSN:0250-6807    

DOI:10.1159/000176241

出版商:S. Karger AG    

年代:1979

数据来源: Karger

摘要:

In studies on the essentiality of nickel, important differences of enzyme activities and also of substrates were established. The results of the present paper show that these changes cannot be explained by a lowered reduction of dietary proteins, since the activity of the proteases rather increased during Ni deficiency. However, the digestion of the starch by α-amylase, being 57% lower, could have been partially responsible for the large differences in the activities of the hepatic enzymes and in the concentrations of the hepatic metabolites and also in the weight gains

ISSN:0250-6807    

DOI:10.1159/000176242

出版商:S. Karger AG    

年代:1979

数据来源: Karger

摘要:

Metabolic reactions during long-time intravenous infusion of glucose in dosages according to basal energy requirements of man were investigated. Infusion of 0.2–0.4 g glucose/kg body weight/h led to the typical behaviour of blood glucose with an initial peak and a subsequent steady state. The steady state was dose-dependent and always higher than the starting value. Insulin always rose significantly with increasing scattering of the individual values with higher glucose loads. With 0.1 g glucose/kg/h, the steady state of blood glucose, after a minimal initial peak, was lower than the starting value, and no change of insulin in the peripheral venous blood could be observed.Free fatty acid levels initially always decreased, but rose again under low glucose loads (0.1 and 0.2 g/kg/h). In all experiments, with an increase of insulin, a decrease of serum potassium was found. Sodium, calcium, bilirubin, creatinine and urea-N did not show any typical change

ISSN:0250-6807    

DOI:10.1159/000176243

出版商:S. Karger AG    

年代:1979

数据来源: Karger