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R M Russell

Publications and source records attributed to R M Russell.

At least 55 records · Page 3Linked to original sources
PubMed1998

An introduction to a UK scheme to help small firms control health risks from chemicals.

The Control of Substances Hazardous to Health Regulations 1994 (COSHH), provide the main British legislation to protect against health risks arising from hazardous substances used at work. Under the regulations, employers have a duty to carry out a suitable and sufficient risk assessment and take steps to ensure exposure is adequately controlled. The paper by Topping et al. (1998) concluded that small firms need more basic, readily available advice on how to effectively control hazardous substances. To meet this need the Health and Safety Executive (HSE) and the Advisory Committee on Toxic Substances (ACTS) have developed a new scheme for the UK. It involves a simple system of generic risk assessments to identify appropriate control strategies and a series of control guidance sheets providing good-practice examples of those strategies for common operations. The approach builds on earlier industry risk banding schemes and HSE's general approach to risk assessment and risk management. To help ensure the advice reaches small firms, HSE is seeking to involve key intermediaries in its dissemination. This paper describes the rationale for the new UK scheme, how it sits in the legal framework, and proposals for its dissemination. The papers by Brooke (1998) and Maidment (1998) set out in detail the technical basis for the scheme.

Air Pollutants, Occupational↗
PubMed1998

The aging gut. Nutritional issues.

With improvements in health care, living standards, and socioeconomic status, more adults are living to old age. As the population ages, it is increasingly important to understand the factors that affect the nutritional status and thus the health status of older adults. Many factors contribute to inadequate nutrition, including health status, financial capacities, mobility, exercise, and physiologic needs. This article considered only the potential changes in nutritional needs because of alterations in the gastrointestinal tract owing to aging. One of the most remarkable changes with aging is the frequent development of atrophic gastritis and the inability to secrete gastric acid. This process affects approximately a third of older adults in the United States and only recently was recognized to be due to infection by H. pylori in the majority of cases. The lack of gastric acid in atrophic gastritis may lead to small intestinal bacterial overgrowth and influences the absorption of a variety of micronutrients, including iron, folate, calcium, vitamin K, and vitamin B12. Lactose maldigestion is a frequent condition in older adults and is extremely common worldwide. The intolerance of dairy products leads to avoidance of these foods and likely contributes to the development of osteopenia. Overall, the small intestine and pancreas undergo astonishingly few clinically significant changes with aging. The relative preservation of overall gastrointestinal function with aging is likely due to the large reserve capacity of this multiorgan system. Further research is needed to define the precise nutritional needs for older adults because simple extrapolation of values from younger adults is now recognized to be insufficient. In addition, it is no longer acceptable to define adequate nutriture in terms of amounts of vitamins needed to maintain serum levels of a nutrient. Further RDAs must consider the functional implications of adequate nutrition. Nutrients in the elderly will be measured as to whether they result in improvements in markers of chronic disease such as homocysteine or, most importantly, in the prevention of chronic disease such as osteoporosis and cardiovascular disease.

Adult↗
PubMed1998

Relationship of plasma carotenoids, retinol and tocopherols in mothers and newborn infants.

OBJECTIVE: We studied the relationship between maternal and cord plasma concentrations of carotenoids, retinol, and tocopherols in normal mother-baby pairs. METHODS: Healthy pregnant women (n = 10) were recruited at a Montréal hospital. Venous blood samples were collected from the mothers at delivery and cord blood was obtained immediately post partum from the umbilical vein after clamping of the cord. All deliveries were full term deliveries and all babies had normal birth weights. Maternal and umbilical cord blood samples were handled identically. Plasma was digested with lipase and plasma carotenoids were extracted and measured using HPLC. RESULTS: Cord plasma concentration of carotenoids were significantly lower than that of maternal plasma (p < 0.001). There was a high correlation of lutein (r = 0.889, p = 0.006) and cryptoxanthin (r = 0.912, p = 0.0002) between maternal plasma concentrations and cord plasma concentrations. The concentrations of the hydrocarbon carotenoids, alpha-carotene and beta-carotene, were also correlated (r = 0.779, p = 0.0133, & r = 0.782, p = 0.0076, respectively) between maternal plasma and cord plasma. Whereas the plasma concentration of the acyclic carotenoid, lycopene, showed no correlation between the two groups, after adjustment for plasma triglycerides, the lycopene correlation between maternal and cord plasma was the highest (r = 0.975, p = 0.0001) of all the carotenoids tested. Cord plasma retinol concentration, which was 50% of that of maternal plasma, was also found to have no correlation with that of maternal plasma. Plasma concentration of alpha-tocopherol showed no correlation between two groups, whereas there was high correlation between cord and maternal gamma-tocopherol concentrations (r = 0.808, p = 0.0047). CONCLUSION: The nutritional status of mothers affects the nutritional status of their babies for certain fat soluble nutrients.

Adult↗
PubMed1998

Interaction between vitamin K nutriture and bacterial overgrowth in hypochlorhydria induced by omeprazole.

Subjects taking a hydrogen pump blocking agent (omeprazole) develop bacterial overgrowth of the small intestine. We tested the hypothesis that this bacterial overgrowth produces menaquinones, which would meet the vitamin requirement in situations of vitamin K deficiency. In a crossover-type design, 13 healthy volunteers eating a phylloquinone-restricted diet for 35 d were randomly assigned to take omeprazole during the first period of study or starting on day 15 until the end of the study. Coagulation times, serum osteocalcin [total osteocalcin and undercarboxylated osteocalcin (ucOC)], plasma phylloquinone, urinary gamma-carboxyglutamic acid, and plasma undercarboxylated prothrombin (PIVKA-II) were measured. Plasma phylloquinone concentrations declined 82% with dietary phylloquinone restriction (P < 0.05) and were not significantly different in the period when the diet was combined with omeprazole treatment (P > 0.05). The mean value for PIVKA-II during the phylloquinone-restricted diet significantly increased 5.7-fold from baseline (P < 0.05); however, the combination of omeprazole treatment and the phylloquinone-restricted diet significantly reduced PIVKA-II values by 21% (P < 0.05) compared with the diet period alone. There were no alterations in total or percentage ucOC concentrations during the phylloquinone-restricted diet or during the period of diet plus omeprazole treatment. Our data support the hypothesis that bacterial overgrowth results in the synthesis and absorption of menaquinones. These menaquinones contribute to vitamin K nutriture during dietary phylloquinone restriction, but not enough to restore normal vitamin K status.

1-Carboxyglutamic Acid↗
PubMed1998

Correlation between carotenoid concentrations in serum and normal breast adipose tissue of women with benign breast tumor or breast cancer.

To evaluate the relationship between carotenoid concentrations in serum and breast tissue, we measured serum carotenoid concentrations and endogenous carotenoid levels in breast adipose tissue of women with benign breast tumor (n = 46) or breast cancer (n = 44). Before extraction, serum was digested with lipase and cholesterol esterase, and breast adipose tissue was saponified. Serum and tissue carotenoids were extracted with ether/hexane and measured by using HPLC with a C30 column. Serum retinoic acid was extracted with chloroform/methanol and measured using HPLC with a C18 column. There were no significant differences in serum carotenoids [lutein, zeaxanthin, cryptoxanthin (both alpha- and beta-), alpha-carotene, all-trans beta-carotene, 13-cis beta-carotene and lycopene], retinoids (retinol, all-trans and 13-cis retinoic acids), and alpha- and gamma- tocopherol concentrations between benign breast tumor patients and breast cancer patients. A substantial amount of 9-cis beta-carotene was present in adipose tissue and was the only carotenoid that had a significantly lower level in benign breast tumor patients than in breast cancer patients. Correlations between carotenoid concentrations in serum and in breast adipose tissue were determined by combining the data of the two groups. Concentrations of the major serum carotenoids except cryptoxanthin showed significant correlations with breast adipose tissue carotenoid levels. When the concentrations of serum carotenoids were adjusted for serum triglycerides or LDL, correlations between serum carotenoid concentrations and breast adipose tissue carotenoid levels markedly increased, including that of cryptoxanthin (P <0. 001). The strong correlation between serum carotenoid concentrations and endogenous breast adipose tissue carotenoid levels indicate that dietary intake influences adipose tissue carotenoid levels as well as serum concentrations, and that adipose tissue is a dynamic reservoir of fat-soluble nutrients.

Adipose Tissue↗
PubMed1998

Serum antioxidant capacity is increased by consumption of strawberries, spinach, red wine or vitamin C in elderly women.

It is often assumed that antioxidant nutrients contribute to the protection afforded by fruits, vegetables, and red wine against diseases of aging. However, the effect of fruit, vegetable and red wine consumption on the overall antioxidant status in human is unclear. In this study we investigated the responses in serum total antioxidant capacity following comsumption of strawberries (240 g), spinach (294 g), red wine (300 ml) or vitamin C (1250 mg) in eight elderly women. Total antioxidant capacity was determined using different methods: oxygen radical absorbance capacity (ORAC) assay, Trolox equivalent antioxidant capacity (TEAC) assay and ferric reducing ability (FRAP) assay. The results showed that the total antioxidant capacity of serum determined as ORAC, TEAC and FRAP, using the area under the curve, increased significantly by 7-25% during the 4-h period following consumption of red wine, strawberries, vitamin C or spinach. The total antioxidant capacity of urine determined as ORAC increased (P < 0.05) by 9.6, 27.5, and 44.9% for strawberries, spinach, and vitamin C, respectively, during the 24-h period following these treatments. The plasma vitamin C level after the strawberry drink, and the serum urate level after the strawberry and spinach treatments, also increased significantly. However, the increased vitamin C and urate levels could not fully account for the increased total antioxidant capacity in serum following the consumption of strawberries, spinach or red wine. We conclude that the consumption of strawberries, spinach or red wine, which are rich in antioxidant phenolic compounds, can increase the serum antioxidant capacity in humans. J. Nutr. 2383-2390, 1998

Aged↗
PubMed1998

Postprandial plasma carotenoid responses following consumption of strawberries, red wine, vitamin C or spinach by elderly women.

This study investigated the postprandial plasma responses of carotenoids for 24 h after feeding five specific breakfast beverages; four of which had low or no carotenoid content. In seven fasting healthy elderly female subjects a blood sample (baseline) was obtained, after which they were given a breakfast beverage, containing one of the following: 1) strawberries (240 g); 2) ascorbic acid (1250 mg); 3) spinach (294 g); 4) red wine (300 mL); and 5) control (breakfast beverage only). Blood samples were collected at 0.5, 1, 4, 7, 11, 15 and 24 h. Plasma carotenoids were measured using HPLC. No significant differences were found in the levels of the plasma carotenoids measured among the various treatments at baseline. In the spinach treatment, plasma lutein, zeaxanthin and beta-carotene levels at 7, 11, 15 and 24 h were significantly higher than those at baseline, as expected. All of the carotenoids measured in the control and vitamin C treatments, at subsequent sampling times were not significantly different from those at baseline. However, for most carotenoids, strawberry and red wine feeding resulted in significantly lower carotenoids values from baseline at 11 and 15 h. Subjects who received a diet with low levels of carotenoids, but whose postprandial plasma levels of carotenoids remain steady, might be explained by a mechanism that promotes secretion of carotenoids into the circulation. Assuming that plasma carotenoids are being used over time, we hypothesize that strawberries and red wine contain some substances that interfere with the secretion of carotenoids into the circulation.

Aged↗
PubMed1998

The interaction between vitamin K nutriture and warfarin administration in patients with bacterial overgrowth due to atrophic gastritis.

Atrophic gastritis patients have intestinal bacterial overgrowth which could produce menaquinones. The aim of this study was to evaluate the interaction between a diet low in phylloquinone and minidoses of warfarin in subjects with and without bacterial overgrowth. Subjects with atrophic gastritis (indicated by serum pepsinogen ratio) and healthy volunteers were studied while fed a restrictive phylloquinone diet and while receiving a minidose of warfarin. Coagulation times, serum osteocalcin, serum undercarboxylated osteocalcin, plasma phylloquinone, plasma K-epoxide, plasma undercarboxylated prothrombin (PIVKA)-II and urinary gamma-carboxyglutamic acid (Gla) were measured. At baseline, there were no differences between groups for any variable measured. Comparisons between baseline and post intervention in both groups, showed significant increases in circulating levels of K-epoxide, PIVKA II and undercarboxylated osteocalcin. However, no differences were observed when comparisons were made between groups. Our data do not support the hypothesis that bacterial synthesis of menaquinones in patients with bacterial overgrowth due to atrophic gastritis confers considerable resistance to the effect of warfarin.

Aged↗
PubMed1998

Plasma carotenoid concentrations are inversely correlated with fat mass in older women.

The relationship between body composition, as measured by body mass index and bioelectrical impedance analysis, and baseline plasma carotenoid concentrations was determined in 36 healthy younger (20-40 y) and older (60-80 y) men and women (nine per group). Changes in plasma carotenoid concentrations after 15 d of consuming a controlled high-carotenoid diet were also correlated with body composition (p<0.05). Older women, who had highest percentage of body fat (38%) among the four groups, showed significant and inverse correlations between body composition (defined by body mass index, percentage of body fat, fat mass and fat free mass) and baseline plasma carotenoid concentrations. Younger women, who had 29% percent body fat, showed a significant and inverse correlation only between body mass index and plasma beta-carotene. However, younger and older men, who had lower percentages of body fat (23% and 22%, respectively), did not show any correlation between body composition measures and baseline plasma carotenoid concentrations. The increases of plasma concentrations of alpha-carotene and beta-carotene after 15 d of consuming a high-carotenoid diet were significantly and inversely associated with percentage of body fat and fat mass in older women only. Thus, fat mass appears to influence serum carotenoid concentrations in only certain subjects (i.e. older women) who have relatively high percentage of body fat.

Adipose Tissue↗
PubMed1997

Nutrition.

Explore the source record for details and available documents.

Exercise↗
PubMed1997

New views on the RDAs for older adults.

The oldest age category in the 1989 edition of the Recommended Dietary Allowances (RDAs) is 51 years and above. Future committees on dietary reference intakes will likely define recommendations for age categories older than this. Instead of extrapolations from data derived from experiments on younger people, future RDAs should be derived directly from experiments on older people. Further, scientists are now interested in the amount of the nutrient that it takes to prevent chronic diseases from occurring rather than to prevent deficiencies, and this will likely influence RDA numbers. A review of past and current data suggests that the current RDAs for the elderly are too low for riboflavin, vitamin B-6, folic acid, vitamin B-12, vitamin D, and calcium, and are probably too high for vitamin A.

Aged↗
PubMed1997

Nutrition Screening Initiative Checklist may be a better awareness/educational tool than a screening one.

OBJECTIVE: To evaluate the Nutrition Screening Initiative (NSI) checklist as a screening and an awareness/educational tool in an elderly population. DESIGN: Epidemiologic follow-up study. Information similar to the questions of the NSI checklist was collected by the Nutrition Status Survey of Boston elders between 1981 and 1984. Vital status of volunteers was obtained during 8 to 12 years of follow-up. SUBJECTS/SETTING: Community-dwelling men (n = 200) and women (n = 381) aged 60 years and older who participated in the survey. STATISTICAL ANALYSES PERFORMED: Multivariate analysis was used to assess the association between mortality and each of the NSI-similar questions and the cumulative score, which is the sum of the values assigned to each question. Attributable risk percent, a measure of association, was calculated to measure the percentage of deaths that could potentially be prevented if the risk factors or their consequences were eliminated. RESULTS: Eating meals alone, problems biting or chewing, difficulties with shopping or cooking, and taking more than three medications per day were positively associated with mortality (P < .05). The cumulative score, although significant, was a weaker predictor of mortality. Attributable risk percent of mortality was 19.9% and 51.2% for men and women, respectively. APPLICATIONS/CONCLUSIONS: Some but not all of the individual questions of the NSI checklist equivalent were significantly associated with mortality and identify specific problems that may have a long-term negative effect yet may be missed if the cumulative score were the sole criterion for screening people. The attributable risk percent suggests that the checklist may be best used as an awareness/educational tool as intended originally and could have an important public health effect on early death of community-dwelling elderly people.

Aged↗
PubMed1997

Measurement of retinoids and carotenoids in breast adipose tissue and a comparison of concentrations in breast cancer cases and control subjects.

A case-control study of the associations of retinoids and specific carotenoids with breast cancer using concentrations of these nutrients in breast adipose tissue was conducted among women attending a breast clinic in the Boston area in 1989-1992. Breast adipose tissue was collected during breast biopsy. Cases (n = 46) were women whose biopsies revealed invasive or in situ breast cancer; control subjects (n = 63) were women whose biopsies revealed benign disease. We observed inverse associations between breast adipose concentrations of retinoids and carotenoids and risk of breast cancer, although not all were statistically significant. The multivariate-adjusted odds ratio comparing women above the median value of the control group for retinol with those below or equal to the median was 0.71 (95% CI: 0.26, 1.93; NS); corresponding odds ratios were 0.61 (95% CI: 0.23, 1.64; NS) for retinyl palmitate, 0.30 (95% CI: 0.11, 0.85) for beta-carotene, 0.32 (95% CI: 0.11, 0.94) for lycopene, and 0.68 (95% CI: 0.27, 1.73; NS) for lutein/zeaxanthin. There was a nonsignificant positive correlation (r = 0.23, P = 0.15) between breast adipose tissue concentrations of retinol and dietary intake of preformed vitamin A, including supplements measured by using a food-frequency questionnaire. No correlation was found between breast adipose concentrations of carotenoids and intake of dietary carotenoids. These data suggest that higher breast adipose concentrations of retinoids and some carotenoids may be associated with decreased risk of breast cancer and that further examination of these relations is warranted.

Adipose Tissue↗
PubMed1997

Short- and long-term beta-carotene supplementation do not influence T cell-mediated immunity in healthy elderly persons.

Supplementation of healthy elderly persons with beta-carotene has been considered a way to enhance immune responses. In study 1 the short-term effect of beta-carotene (90 mg/d for 3 wk) on immunity was assessed in a randomized, double-blind, placebo-controlled longitudinal comparison of healthy elderly women. In study 2 the long-term effect of beta-carotene (50 mg every other day for 10-12 y) on immunity was assessed in a randomized, double-blind, placebo-controlled longitudinal comparison of men enrolled in the Physicians' Health Study. Subjects from both studies taking active supplements had significantly greater plasma beta-carotene concentrations than did subjects taking placebo. The pre- to postintervention change in delayed-type hypersensitivity skin test responses between beta-carotene and placebo groups in the short-term study was not significantly different, nor was the response between treatment groups in the long-term study. There were no significant effects due to beta-carotene supplementation on in vitro lymphocyte proliferation, production of interleukin 2, or production of prostaglandin E2 as a result of short- or long-term beta-carotene supplementation. In addition, there were no differences in the profiles of lymphocyte subsets [total T cells (CD3+), T helper cells (CD4+), T cytotoxic-suppressor cells (CD8+), and B cells (CD19+)] due to short- or long-term beta-carotene supplementation, nor were there differences in percentages of CD16+ natural killer cells or activated lymphocytes (cells expressing interleukin 2 transferrin receptor) due to long-term beta-carotene supplementation. Consistent results from these two trials show that beta-carotene supplementation did not have an enhancing or suppressive effect on T cell-mediated immunity of healthy elderly.

Aged↗