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Biomedical subjects

N Fisher

Publications and source records attributed to N Fisher.

At least 55 records · Page 3Linked to original sources
PubMed1985

Cereal dietary fiber consumption and diverticular disease: a lifespan study in rats.

The relationship between consumption of dietary fiber (DF) from white bread, wholemeal bread, or bran and the development of diverticular disease of the colon has been investigated in a lifespan study using 1800 Wistar rats in nine diet groups. Use of the rat as a model for the human condition was validated by demonstration of significant relationships between fiber intake and fecal output and transit time, and the observation of true acquired diverticula, both single and multiple. Significant inverse relationships (mostly with p less than 0.001) were observed between the incidence of diverticula (and prediverticula) and the concentrations of fiber in the diets, measured by the neutral detergent fiber and Southgate methods. The study offers strong support to the Painter-Burkitt view of human diverticular disease as being due to fiber deficiency, if the extrapolation from rat to man is valid. On the same assumption, the amount of additional fiber required to be consumed in order to achieve a substantial reduction in incidence of the disease is very large. Effects of fiber on body weight, food intake, mineral levels, blood composition and properties, mortality, organ weights, and incidence of tumors and lesions are reported. Significantly fewer mammary tumors were found in rats fed the very high fiber stock diet than in those fed the purified diets.

Animals↗
PubMed1985

Gallium-positive Lyme disease myocarditis.

In the course of a work-up for fever of unknown origin associated with intermittent arrhythmias, a gallium scan was performed which revealed diffuse myocardial uptake. The diagnosis of Lyme disease myocarditis subsequently was confirmed by serologic titers. One month following recovery from the acute illness, the abnormal myocardial uptake completely resolved.

Gallium Radioisotopes↗
PubMed1983

Short-term toxicity study in rats of chlorinated cake flour.

Male and female Wistar rats were fed for 28 days on a diet containing either chlorinated (1257 or 2506 ppm chlorine) or unchlorinated flour. No significant differences between groups in body weight were observed in the males. A significant inverse correlation between body weight and treatment level, attributable to a corresponding trend in food intakes, was found for the females only. No significant differences between absolute organ weights were found, but when the weights were adjusted for covariance with body weight, dose-related increases in kidney weight (males) and liver weight (both sexes) were found. Histopathological examination revealed no pathological tissue changes attributable to the chlorination of the flour.

Animals↗
PubMed1983

Long-term toxicity and carcinogenicity studies of cake made from chlorinated flour. 1. Studies in rats.

Wistar rats were fed for 104 wk on cake-based diets in which the cake, prepared from unchlorinated flour, or flour treated with 1250 or 2500 ppm chlorine, formed 79% of the diet on a 12.6% moisture basis. A fourth group was fed stock diet 41B. No differences in appearance, health, behaviour or mortalities attributable to the flour treatment were observed. Female but not male mortalities were significantly higher for cake-fed rats than for those fed diet 41B. Dose-related haematological effects were seen at various stages in cake-fed rats. Dose-related increases in plasma alanine and aspartate aminotransferases were noted at 12 months in males but not in females, for whom all the values were elevated. A dose-related diminution in blood sugar at 12 months was seen only in females. A dose-related increase in urinary aspartate aminotransferase was seen only in males. Urinary N-acetylglucosaminidase activity per mg creatinine did not differ significantly between groups. At post mortem a dose-related reduction in spleen weight was found in the females only. The lesions found were those expected in ageing rats, but were observed earlier in rats fed cake. Glomerulonephrosis affected rats fed cake more than those fed diet 41B. Cake diets promoted nephrocalcinosis, unrelated to flour treatment. Increased splenic haematopoiesis occurred in about half of the females in the cake diet groups but less frequently in males or in rats fed diet 41B. Tumours were mainly chromophobe adenomas of the pituitary, common in rats. Insulomas were seen in two males in each of the groups fed on cake made from chlorinated flour, but an earlier form of this tumour was found in all cake groups and its incidence is thus regarded as unrelated to the flour treatment. The incidence of tumours of the reticuloendothelial system was not related to flour treatment. Covalent chlorine concentrations in the perirenal fat of the cake-fed rats were correlated with treatment levels, with values of 50-912 ppm in males and 59-1174 ppm in females. Since concentrations in the lipid of the diet fed to the animals were much higher than these, accumulation of the additive was absent or negligible. The chlorine concentrations in the perirenal fat of male and female rats fed diet 41B were 62 and 72 ppm respectively.

Animals↗
PubMed1983

Long-term toxicity and carcinogenicity studies of cake made from chlorinated flour. 2. Studies in mice.

Male and female Theiller's Original strain mice were fed for 16 and 17 months respectively on diets in which cake, prepared from flours treated with 0, 1250 or 2500 ppm chlorine, formed 79% by weight on a 12.6% moisture basis. Body weights and food intakes were unaffected by flour treatment but all of the animals on cake diets showed significant increases in body weight compared with controls on a standard diet and became obese. Mortalities in the males were not related to treatment, but in the females there was excess mortality in the treated groups compared with the cake control group, after 13 months in the 1250 group and after 15 months in the 2500 group. No consistent treatment-related effects were observed in the haematological, biochemical and renal-function studies. Dose-related increases in heart and kidney weights and a dose-related decrease in ovary weight were seen in females. No evidence of carcinogenicity resulting from flour treatment was obtained but the early ending of the study, necessitated by high mortalities, greatly diminished the value of this finding. Concentrations of covalently bound chlorine in the perirenal fat were positively correlated with treatment level, but were considerably below those present in the lipid content of the diets on which the mice were fed.

Animals↗
PubMed1981

Hydrolysis of the phytate of wheat flour during breadmaking.

1. Differences in the extent of breakdown of phytate in wholemeal and white flours prepared from three wheats when the flours were made into bread using the three main UK commercial breadmaking processes were investigated. 2. The extent of breakdown (31-46% for wholemeal breads, 88-99% for white breads) was not proportional to the relative processing times involved (1-4 h). The importance of destruction of phytate in the oven is stressed. 3. The phytase (myo-inositol hexaphosphate phosphohydrolase, EC 3. 1. 3.8) activities of the wholemeal flours and the yeast were determined. Re-examination of some information in the literature enabled the relative importance of these activities, and of the various stages of breadmaking, in determining the extent of hydrolysis of phytate to be assessed. 4. Average values for the molar ratio, phytate: zinc, of 22:1 and 0.8:1 were calculated for wholemeal and white breads respectively. The nutritional significance of these results is discussed.

6-Phytase↗
PubMed1980

Cereal foods today and tomorrow.

The present place of cereal foods in the UK diet is assessed. In particular, the role of wheat and of bread white or brown in providing nutrients is reviewed. An examination is carried out of the forces--including nutritional and medical suggestions that the health of the nation would benefit from increased use of 'unrefined' cereals--which favour or inhibit change in future production and consumption of cereals in the UK.

Bread↗
PubMedDate not supplied

The role of polymorphisms of glutathione S-transferases GSTM1, M3, P1, T1 and A1 in susceptibility to alcoholic liver disease.

AIMS AND METHODS: Oxidant stress is proposed to be an important pathogenic factor in liver damage related to alcohol. The glutathione S-transferases (GSTs) are a group of polymorphic enzymes that are important in protection against oxidant stress. As there is evidence for genetic susceptibility to alcohol-related liver disease we have compared the frequency of polymorphisms of GSTM1, M3, P1, T1 and A1 by polymerase chain reaction (PCR) on leucocyte DNA in patients from North Staffordshire, Birmingham and Liverpool with alcohol-related chronic liver disease heavy drinking and normal local controls. RESULTS: There were no significant differences in GSTM1, GSTM3 or GSTP1 genotype frequencies among patients, drinking and non-drinking controls from the three centres. There was a significant increase in the GSTT1 null Liverpool alcoholic liver disease (ALD) patients compared with corresponding non-drinking controls (26.3 and 14.6%, respectively; P = 0.044, odds ratio (OR) = 2.1, 95% CI = 1.1-4.7) though this was not repeated in the Birmingham and North Staffordshire cohorts. For GSTA1, the -69 CC genotype was associated with increased risk of ALD in the Liverpool group, but a reduced risk in the North Staffordshire group. CONCLUSIONS: We have failed to demonstrate within the limitation of a case-control study a reproducible significant association of GST polymorphisms with susceptibility to ALD but there are suggestions that GSTA1 and GSTT1 warrant further study.

Chi-Square Distribution↗