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T K Basu

Publications and source records attributed to T K Basu.

At least 55 records · Page 3Linked to original sources
PubMed1987

Age-related olfactory and taste changes and interrelationships between taste and nutrition.

This article critically reviews the literature on age-related olfactory and taste changes and the interrelationships between nutrition and taste. Age-related taste alterations are controversial, but there is consensus on an olfactory decline with age. Much of the age-related chemoreceptive research has used inappropriate methodology, thus leaving many findings inconclusive. Changes in the taste system with age may be related to nutrient intake, which in turn can be influenced by taste. Literature on such interrelationships is limited. Vitamins A, thiamin, B-6, B-12, folacin, zinc, and copper are thought to influence taste function. Moreover, those nutrients are of concern in the aged. The use of appropriate methodology is critical not only for the sensory but also for the nutritional aspects, particularly for qualitative and quantitative assessments of nutrient intakes. This review considers the experimental deficiencies (small sample size, inappropriate age range, inadequate psychophysical and stimuli presentation procedures, and poor dietary intake assessment) of studies reported in the literature and suggests major needs for research.

Aging↗
PubMed1987

Protective effect of beta-carotene against colon tumors in mice.

The effect of dietary beta-carotene on colon carcinogenesis induced by 1,2-dimethylhydrazine [(DMH) CAS: 540-73-8] was studied in female inbred Swiss Webster (ICR) mice. At age 10 weeks and continuing throughout the experiment, mice received diets consisting mainly of natural foods (laboratory chow) and containing 2 or 22 mg beta-carotene/kg. At age 15 weeks they received 7 weekly sc injections of DMH (total dose: 196 mg DMH X diHCI/kg body wt). When autopsied 31 weeks after the first DMH injection, the incidence (percent of mice with tumors) and multiplicity (number of tumors/tumor-bearing mouse) of colon tumors were reduced by half in the mice supplemented with beta-carotene. There was a much greater decrease in adenocarcinomas than in adenomas. Mice observed for 13 additional weeks revealed that the mortality rate, due largely or wholly to colon cancer, was only about half in supplemented mice. Mice sacrificed 12 weeks after the first dose of DMH (i.e., well before tumors appeared) showed mild colon mucosal hyperplasia. beta-Carotene supplementation, however, did not alter this, indicating that the protective effect against colon cancer may have occurred at a late stage of carcinogenesis.

Animals↗
PubMed1987

Selenium and cabbage and colon carcinogenesis in mice.

The influence of dietary selenium and cabbage on the formation of colon tumors in female Swiss mice treated with 1,2-dimethylhydrazine [(DMH) CAS: 540-73-8] was reported. Mice received a control diet (laboratory chow), the control diet plus selenium in the drinking water (1 mg/liter), or the control diet with added cabbage (12.8 g/100 g diet). They also received 8 weekly sc injections of DMH. The experiment was divided into two time periods: a) from 5 weeks before the first injection until 3 days after the last one (initiation period), and b) the subsequent 19.5 weeks until sacrifice of the mice (promotion period). Selenium had a strong protective effect when given during the initiation period; adenomas were reduced to a much greater extent than adenocarcinomas. The only effect of selenium supplementation in the promotion period was a small decrease in adenomas. Cabbage apparently had two opposing actions. It increased tumor incidence, particularly adenocarcinomas, if given in the initiation period, but it reduced adenoma formation considerably when given in the promotion period.

1,2-Dimethylhydrazine↗
PubMed1986

Effects of estrogen and progestogen on the ascorbic acid status of female guinea pigs.

Female, adult guinea pigs were fed a low ascorbic acid diet ad libitum. Oral administrations of either estinyl (5 micrograms) or progestogen (250 micrograms) in combination with 5 mg of ascorbic acid (minimum requirement) daily for 21 d, resulted in significantly lower (P less than 0.05) concentrations of ascorbic acid in plasma, liver, adrenals and urine than in animals receiving only 5 mg of the vitamin. None of these animals showed any clinical signs of ascorbic acid deficiency. Clinical manifestations of scurvy were exhibited, however, when animals receiving no ascorbic acid supplement were treated with the steroid hormones for 7 d. All of these animals died by d 10. On the other hand, the animals receiving neither ascorbic acid nor the steroids remained free from any signs of scurvy, except one (out of six), which died by d 12. In vitro studies revealed a markedly higher rate of oxidation of ascorbic acid in the presence of either estinyl or progestogen than in untreated controls. These results were further supported by a higher level of plasma ceruloplasmin in animals receiving a combination of estrogen and progestogen than in animals receiving no hormones. An in vivo dose-related effect of ascorbic acid indicated that the steroid-mediated lowering effect of the vitamin status could be counteracted by increasing the dose of ascorbic acid from 5 to 10 mg/d for 2 wk. These results suggest that the interactions between oral contraceptive hormones and ascorbic acid may be of clinical importance only in the case of borderline intake of the vitamin.

Adrenal Glands↗
PubMed1985

Retinol and postoperative colorectal cancer patients.

In order to determine whether low plasma levels of retinol and its carrier (retinol binding protein) are related to increased risk of cancer recurrence, these were measured in 103 patients who had had colorectal cancer surgically removed. According to the modification of the Dukes' classification, 66 had B2 tumours (with no nodal involvement' and 37 had C tumours (with lymph-node metastases). These patients were part of the Cross Cancer Institute Adjuvant GI Cohorts who were on the control arms receiving no further treatment. At the time of blood sample collection, they were believed to be free of neoplastic disease. The post-operative patients were found to be associated with subnormal circulatory levels of retinol (43.3 micrograms dl-1 vs 65.3 micrograms dl-1) and its carrier protein (4.6 mg dl-1 vs 5.7 mg dl-1), when compared with apparently healthy subjects. The latter being more markedly depressed in patients with "C" type tumour (3.8 mg dl-1) than that in those with "B2" type tumour (5.0 mg dl-1). These findings appeared to be persistent during the follow-up study when a second blood sample was collected, one to four months later from 40 patients. Furthermore, the initial plasma retinol level in conjunction with RBP was found to be even lower in 12 patients (35.1 micrograms dl-1, 3.7 mg dl-1) who subsequently had cancer recurrence than in those who remained free of apparent cancer (44.5 micrograms dl-1, 4.6 mg dl-1). The lowest initial values of retinol (19.3 micrograms; 18.8 micrograms dl-1) and RBP (2.4; 1.6 mg dl-1) recorded in the study were seen in the only two patients who died of the disease at the time of follow-up.

Adult↗
PubMed1985

The conditioning effect of large doses of ascorbic acid in guinea pigs.

The influence of prolonged exposure of guinea pigs to excessive ascorbic acid (AA) on the outcome of pregnancy, as well as the adaptive effect of the vitamin either during preweanling life or following weaning, were examined. Continuous exposure to AA (1 mg/mL drinking water) from the time they were first mated up to the time of second pregnancy, had no significant effect on the number of offspring and on their weights at birth, when compared with that of the animals receiving 0.1 mg AA/mL drinking water. However, change in AA intake from 1 to 0.1 mg/mL drinking water, at the age of 21 days, resulted in a significant loss in body weight and reductions in the plasma, leukocyte, and adrenal concentrations of AA, as compared with those of the pair-fed animals receiving 0.1 mg/mL drinking water throughout. The present study also indicated that the conditioning effect is less pronounced in guinea pigs when exposed to the high AA following weanling age than in utero.

Adrenal Glands↗
PubMed1984

An in vitro effect of ascorbate on the spontaneous reduction of sodium nitrite concentration in a reaction mixture.

Nitrite is known to react with free amines to form nitrosamines which may have carcinogenic activity. The present study provides evidence showing that addition of ascorbic acid in a reaction mixture results in a spontaneous decrease in nitrite concentration. The nitrite lowering effect of ascorbic acid appears to correlate with the rate of oxidation of the vitamin to dehydroascorbic acid, suggesting that ascorbic acid may be involved in the reduction of nitrite to nitrogen oxide.

Ascorbic Acid↗
PubMed1983

Effect of pharmacological doses of ascorbic acid on the hepatic microsomal haemoproteins in the guinea-pig.

1. Ascorbic acid deficiency results in a reduction in the activity of the hepatic mixed function oxidase systems in the guinea-pig. In this study, male Dunkin-Hartley guinea-pigs were given 0, 50, 100, 200 or 300 mg ascorbic acid/d in two equal doses in buffered sucrose solution (200 g/l) for 4 d. Controls received an equal volume of sucrose solution. 2. A dose of 50 mg ascorbic acid/d resulted in a significant rise in the specific activities of both cytochromes P-450 and b5. At doses of 200 and 300 mg ascorbic acid/d the concentration of both haemoproteins was significantly lower than the control values. These effects were mirrored by total microsomal haem concentration. 3. These results suggest that when given in large doses, ascorbic acid ceases to act simply as a vitamin and should be considered a drug competing for substrates and cofactors with co-administered drugs and endogenous substrates such as cholesterol.

Animals↗
PubMed1983

Effects of protein malnutrition and ascorbic acid levels on drug metabolism.

The duration of action of drugs (or other environmental chemicals) is dependent on their rate of metabolic deactivation and elimination from the body. Termination of activity is achieved either through excretion of the drug via the kidney and bile or, more commonly, through metabolic deactivation by enzymes of the liver and other tissues. In recent years, it has become increasingly obvious that nutritional status is one of the major factors capable of modifying the pharmacological effect of drugs. Numerous studies have indicated that the process of drug metabolism may be affected by acute starvation, undernutrition, protein nutrition, and deficiencies of minerals, vitamins, and lipids. Although most of the evidence concerning the effects of nutrition on the metabolism of drugs has been derived from studies on experimental animals, there is significant fragmentary human data to show that the same effects may occur in man. This paper will discuss the influence of nutritional status with particular references to protein and ascorbic acid on the metabolism of foreign compounds including drugs. The interrelationships of nutrition and the metabolism of drugs are an important consideration in view of the widespread recurrence of primary malnutrition in the developing countries, and of secondary malnutrition in more affluent societies, especially in debilitated chronically ill patients, in postoperative patients, and in those whose dietary manipulations are carried out in weight-reducing regimens. The effects of nutrition on drug metabolism may be viewed as an extension of the search for one of the environmental factors that modify drug action.

Animals↗
PubMed1983

High-dose ascorbic acid decreases detoxification of cyanide derived from amygdalin (laetrile): studies in guinea pigs.

Cysteine, a sulphur-containing amino acid, is required to metabolize ascorbic acid (as ascorbate sulphate) and detoxify cyanide (to thiocyanate). In guinea pigs, conjoint use of laetrile (a cyanogenic glycoside) and ascorbic acid (in large doses) decreases the detoxification of cyanide derived from laetrile through diminishing the availability of cysteine, but not impairing hepatic rhodanese activity, which is involved in the detoxification of cyanide to thiocyanate. These results agree with the symptoms of a sublethal dose of KCN toxicity manifested by the animals. The studies, therefore, indicate that individuals taking megadoses of ascorbic acid concurrently with laetrile may be subject to self-poisoning.

Amygdalin↗
PubMed1983

A goitrogenic agent from millet (Pennisetum typhoides) in Darfur Province, Western Sudan.

Serum samples from girls from an elementary school in Western Sudan with grades O, I and II/III goitre were examined for their thiocyanate, cysteine, thyroxine, TSH and T3 concentrations. The concentrations of thiocyanate in all girls was higher than that reported in the literature for Nigerians, but the concentrations of thiocyanate were nevertheless significantly elevated, and those of thyroxine significantly lowered in girls with grades I and II/III goitre as compared with grade O. There were no significant differences between any of the groups in the concentrations of cysteine or TSH and T3. The predominant staple food eaten in this area of Sudan is millet and evidence is produced that this contains a goitrogenic thionamide which could be a factor in causing the endemic goitre.

Child↗
PubMed1983

Longitudinal studies of nutritional status in patients having chemotherapy for testicular teratomas.

The nutritional status of 14 patients with metastatic testicular teratomas was measured longitudinally through four courses of treatment with vinblastine and bleomycin, or vinblastine, bleomycin and cis platinum regimens. On each regimen patients lost weight during each course and did not entirely regain it between courses. The nutritional status with respect to retinol and vitamins E, B1 and B6 also fell during each course. The fall in plasma retinol levels was correlated with a fall in the plasma level of retinol-binding protein (RBP). In patients treated with the vinblastine and bleomycin regimen, plasma retinol levels were higher at the beginning of the fourth course than at the start of the treatment, possibly due to improved synthesis of RBP. In contrast, there was no overall improvement in B1 status.

Adult↗