This study was designed to determine the effect of hexachlorobenzene (HCB) on rat reproduction. Dietary concentrations of 0, 10, 20, 40, 80, 160, 320, and 640 ppm of HCB were fed to Sprague-Dawley rats in a four generation reproduction study. Pregnancy (number of dams whelping/number of dams mated), viability (pups surviving 5 days/pups born alive), and lactation (pups weaned/live pups on day 5 less culls) indices were measured. Body weight gain of pups was monitored. HCB residues were measured in the 21-day-old pups of the F1a and F3a generations. The two highest dietary concentrations were toxic to the F0 generation females and 50% and 20% respectively, died. Sucking pups were particularly sensitive and many died prior to being weaned. The viability index was zero in the F1a and F1b generations for pups from dams fed 320 and 640 ppm of HCB and only 55% for the 160 ppm group. The lactation index decreased from 30% for the F1a and F1b generation pups to 0 for the F2a and F2b generation pups in the 160 ppm group. Also, the lactation index decreased from 93% in the F1a generation to 40% in the F3b generation for the 80 ppm group. Birth, 5-day and 21-day body weights of pups were decreased by treatment. HCB residues accumulated in the pups in a dose-related manner. The relative liver weight and aniline hydroxylase activities were increased in weanlings from dams fed 40 ppm of HCB. No gross abnormalities were observed in the pups.

Male and female rats were raised from weaning on diets containing 0, 20, and 40 ppm of hexachlorobenzene (HCB) for three months. The animals were then placed on an HCB-free diet and dosed with either sodium phenobarbital or carbon tetrachloride. Animals were killed at 0, 15, and 30 days on the HCB-free regimen and tissue residues determined. Plasma cholinesterase activity was depressed by carbon tetrachloride treatment as were liver aniline hydroxylase andN-demethylase activities. Phenobarbital treatment increased liver aniline hydroxylase andN-demethylase activities. HCB decay profiles were established for plasma, fat, and liver. No direct correlation was observed between induction of enzyme activity and rate of disappearance of HCB residues in liver tissue.

1.1. Three substrates of cholinesterase (ChE, E.C. 3. 1. 1. 8) were used to determine the esterase activities from different tissues of albino rats.2.2. The results showed that indophenyl acetate (IPA), acetylthiocholine iodine (ASChI), and butyrylthiocholine iodide (BSChI) were hydrolysed selectively by esterases found in different tissues.3.3. The brain and muscle were found to be rich in esterases catalysing the hydrolysis of ASChI, whereas the liver, kidney, and testis were found to be rich in esterases catalysing the hydrolysis of IPA.4.4. This study suggests that esterases other than cholinesterases may be involved in the hydrolysis of IPA.

Lead ingestion at 100 and 200 ppm for 36 and 90 days had no effect on the disappearance of DDT residues (and metabolites) from adipose tissue of rats. Lead alone, and lead fed to DDT pre-treated animals had no effect on body weight gain, liver weights, liver vitamin A, liver protein,in vitro liver carboxylesterase activity and pentobarbital sleeping times.

Male rats were orally dosed with Aroclor 1254 and residues were found in all tissues analyzed, with the greatest concentration in the fat. The GLC-EC pattern of the residues was different from the standard mixture administered, indicating that all components were not metabolized at the same rate. Higher residues were found in the carbon tetrachloride-treated rats. Aroclor 1254 residues in the brain, spleen, blood, testes, heart, kidney and fat were reduced by 90, 84, 80, 79, 78, 76, 64 and 33% respectively in 20 days. Aroclor 1254 significantly increased the size of the liver and also the percent lipid in the liver. Aroclor 1254 was found to potentiate the toxicity of carbon tetrachloride in the rat.

1.1. Esterase activities on indophenyl acetate were determined in extracts of livers, kidneys, brain, thigh muscles and testes of albino rats.2.2. Livers and kidneys had higher esterase activity than brain, muscles or testes.3.3. No significant loss of esterase activities was observed when the tissues were left untouched in the body 1–24 hr after decapitation.4.4. Analyses of tissues from the same liver on 5 successive days or at 1- to 60-day intervals were reproducible.5.5. The method was also used to demonstrate esterase activities in tissues of DDT-fed rats and progeny and in necropsy samples of human livers.

Partially consumed jars of commercial baby food, representing ten food classes having various levels of naturally occurring nitrate, were stored under refrigeration for seven days. Under the conditions used in the present experiment nitrite did not accumulate to levels which would present a health hazard in regard to methaemoglobinemia.

(1)Three hypocholesterolemic agents that act in vivo by inhibition of cholesterol synthesis were studied in regard to their effect on liver ubiquinone and vitamin A levels.(2)Benzmalacene, SK and F No. 525A and AY9944 although modifying iso-prenoid synthesis did not lower liver ubiquinones of the rat.(3)None of the inhibitors studied adversely affected vitamin A metabolism as indicated by liver stores of the vitamin.

The chemical changes (oxidation/nitrosation) of meat proteins during digestion lead to a decrease in their nutritional value. Moreover, oxidized and nitrosated amino acids are suspected to promote various human pathologies. To investigate the mechanisms and the kinetics of these endogenous protein modifications, we used a dynamic artificial digestive system (DIDGI®) that mimics the physicochemical conditions of digestion. The combined effect of meat cooking and endogenous addition of ascorbate and nitrite was evaluated on protein oxidation (by measuring carbonyl groups), protein nitrosation (by measuring nitrosamines), and proteolysis. Considerable carbonylation was observed in the digestive tract, especially under the acidic conditions of the stomach. Nitrosamines, caused by ammonia oxidation, were formed in conditions in which no nitrite was added, although the addition of nitrite in the model significantly increased their levels. Meat cooking and nitrite addition significantly decreased protein digestion. The interactions between all the changes affecting the proteins are discussed.

Abstract Beef steers were fed forage contaminated with technical DDT for 83 days. Fat samples were removed by omentectomy at various intervals after feeding of the contaminated forage had ceased. Residues of p,p′-DDE, DDD, and p,p′-DDT were found. DDD residues declined at the greatest rate, p,p′-DDT declined at an intermediate rate, while p,p′-DDE declined at the slowest rate. In a second experiment technical DDT was administered orally, intraperitoneally, and intravenously to beef steers. Fat samples were removed by omentectomy 3 days after dosing. The steers that received technical DDT intraperitoneally and intravenously stored DDD and p,p′-DDT in the fat at a much lower ratio than the orally treated animals. p,p′-DDT was administered by the oral, intraperitoneal, and intravenous routes in another experiment. Three and 8 days after dosing, the residues in the omental fat of the orally treated animals showed increased DDD to p,p′-DDT ratios when compared to these ratios for the other 2 groups which had declined from pre-treatment levels. The data suggest that p,p′-DDT is dechlorinated to DDD in the rumen of the bovine.

Mevalonic acid was incorporated into the ubiquinone and sterol fractions of rat-liver homogenates. The incorporation of mevalonate was increased approximately 10-fold in the total non-saponifiable matter including sterol by use of the in vitro homogenate system as compared with intact rats. The incorporation into the ubiquinones was decreased. The addition of potential ring precursors, p-hydroxybenzoic acid, L-phenylalanine, or L-tyrosine to the homogenate system did not increase incorporation of mevalonate into ubiquinone.Incubation of subcellular fractions from rat-liver homogenates demonstrated that supernate plus either mitochondria or microsomes were necessary for the biosynthesis of ubiquinone.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTQuantitative Estimation of Vitamins D2 and D3 in Pure SolutionD. H. Laughland and W. E. J. PhillipsCite this: Anal. Chem. 1956, 28, 5, 817–819Publication Date (Print):May 1, 1956Publication History Published online1 May 2002Published inissue 1 May 1956https://pubs.acs.org/doi/10.1021/ac60113a012https://doi.org/10.1021/ac60113a012research-articleACS PublicationsRequest reuse permissionsArticle Views62Altmetric-Citations7LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts

THE destructive action of sodium bentonite on vitamin A in vitro and in vivo has been previously reported by Laughland and Phillips (1954 a, b). In this work the effects of sodium bentonite in experimental diets for rats was studied. Briggs and Spivey (1954) have demonstrated that under certain conditions a vitamin A-deficiency could be produced in chicks by incorporating bentonite in the diet. The present work has been carried out to gain further information concerning the effects of dietary sodium bentonite on the growth of chicks. MATERIALS AND METHODS The birds used in these experiments were sex-linked crossbred pullets (New Hampshire males X Barred Plymouth Rock females). Vitamin A was determined colorimetrically in the non-saponifiable fraction of the livers by means of the antimony trichloride reaction. Liver crude fat was determined by the modification of the Mojonnier procedure described by Bixby et at. (1954) and nitrogen by the …