Effects Of Nutritional Factors Research Articles

Nutrition and Lifestyle Factors on the Risk of Developing Breast Cancer

Aspects of nutrition and lifestyle may be largely responsible for the development of common cancers in Western countries, as indicated by the large differences in breast cancer rates between countries, the striking changes in these rates among migrating populations, and the rapid changes over time within countries. The better informed and increasingly health-conscious population of the present day are intensively seeking to identify and eliminate these putative carcinogenic risk factors and to exploit the preventive effects that have been attributed to certain dietary components. Nutrition and 'lifestyle' may exert its carcinogenic effects indirectly by cell stimulations (alcohol, hormone therapy in postmenopause), inhibition of DNA-repair mechanisms (lack of vitamins), effecting estrogen metabolism (phytoestrogenes), or as promotors to enhance growth of tumours (body mass index). Some 'substances' may act as a carcinogenic itself, for example, aromatic hydrocarbons in tobacco or increased polycyclic aromatic hydrocarbons in well done meat. Individual differences in the effects of nutritional factors on mammary epithelia could be caused by genetic polymorphisms. In this critical review, we focus on current data regarding the effect of nutrition and lifestyle, on the risk of developing breast cancer. A health lifestyle, consisting of 'healthy diet', physical activity, renunciation of stimulants, is recommended from childhood throughout life.

Reduction of the risk of breast cancer

Aspects of nutrition and lifestyle may be largely responsible for the development of common cancers in Western countries, as indicated by the large differences in breast cancer rates between countries, the striking changes in these rates among migrating populations, and the rapid changes over time within countries. The better informed and increasingly health-conscious population of the present day are intensively seeking to identify and eliminate these putative carcinogenic risk factors and to exploit the preventive effects that have been attributed to certain dietary components. Nutrition and 'lifestyle' may exert its carcinogenic effects indirectly by cell stimulations (alcohol, hormone replacement therapy), inhibition of DNA-repair mechanisms (lack of vitamins), effecting estrogen metabolism (phytoestrogen), or as promotors to enhance growth of tumors (body mass index). Some 'substances' may act as a carcinogenic itself, e. g. aromatic hydrocarbons in tobacco or increased polycyclic aromatic hydrocarbons in well done meat. Individual differences in the effects of nutritional factors on mammary epithelia could be caused by genetic polymorphisms. In this critical review, we focus on current data regarding the effect of nutrition and lifestyle, on the risk of developing breast cancer. A health lifestyle, consisting of "healthy diet", physical activity, renunciation of stimulants, is recommended from childhood throughout life.

Effects of nutritional factors on the formation of Anthraquinones in callus cultures of Rheum ribes

Rheum ribes L. (Polygonaceae) is the source of one of the most important crude drugs in Asiatic regions .The medicinal character of rhubarb is due to its anthraquinone content . Different parts of sterile seedlings were cultured on MS medium to study the generation of callus. The explants were cultured with different ranges of plant growth regulators and the best range of plant growth regulators for generation of callus was IBA (1 mg l−1) and BA (1 mg l−1). The content of anthraquinones were determined by HPLC . The concentration of sucrose, vitamins and Myo-inositol and ratio of NO3 to NH4 in the medium was changed and growth rate and content of 2 anthraquinones was determined . The growth rate of callus declined with increased rate of secondary metabolites production. Myo-inositol 100 mg l−1 in the medium increased anthraquinone content and in medium that had NO3/NH4:1/1 the maximum content of anthraquinone was obtained.

Effect of nutritional factors on biochemical, structural and metabolic characteristics of muscles in ruminants, consequences on dietetic value and sensorial qualities of meat

Effect of nutritional factors on biochemical, structural and metabolic characteristics of muscles in ruminants, consequences on dietetic value and sensorial qualities of meat

Effect of nutritional factors on biochemical, structural and metabolic characteristics of muscles in ruminants, consequences on dietetic value and sensorial qualities of meat

Ruminant meat is an important source of nutrients and is also of high sensory value. However, the importance and nature of these characteristics depend on ruminant nutrition. The first part of this review is focused on biochemical and dietetic value of this meat. It offers a panel of quantitative and qualitative contributions, especially through its fatty acids characteristics. Since saturated and trans-monounsaturated fatty acids are considered as harmful to human health, their amount in muscles can be reduced by increasing the proportions of dietary polyunsaturated fatty acids (PUFA) absorbed by the animals. On the contrary, some fatty acids (n-6 and n-3 PUFA, conjugated linoleic acid) specifically incorporated in muscle tissues would play a favourable role in the prevention or reduction of major diseases in human (cancers, atherosclerosis, obesity) and therefore be recommended. The second part of this review treats different aspects of the sensorial qualities of meat. Skeletal muscle structure and its biochemical components influence muscle transformation to meat and sensorial qualities including tenderness, colour, flavour and juiciness. This paper shows how nutrition can influence, in ruminants, metabolic activity as well as muscle structure and composition, and thereby affect meat quality.

Effect of nutritional factors on fatty acid composition of lamb fat deposits

A literature review was made of the influence of nutritional factors on the fatty acid composition of fat deposits and muscles of lambs. A bibliographic data base, containing 979 observations from 108 papers, was made up in such way that one observation corresponded to one group of lambs in one experiment. Each nutritional factor was studied only when number of observations was sufficient. Consequently, special emphasis was given to the effect of dietary ingredients supplying energy or nitrogen on the fatty acid composition of subcutaneous (SC) and perirenal adipose (PR) tissues and in muscles of lambs. Regardless of sex, breed and breeding conditions, all the tissues examined showed a similar pattern of modification in fatty acid composition with diets. In milk fed lambs the pattern of fatty acids largely reflected the dietary fat pattern. The fatty acid of stored fats before weaning had an influence on fatty acid composition of fat deposits and muscle, several months after weaning. When the diets were rich in beet pulp or in fish meal the proportion of C 18:1 was significantly increased and the proportions of C 18:0, C 18:2 and C 18:3 decreased in fat tissues. Inclusion of maize in diet resulted in an increase in linoleic acid content in fat deposits. Inclusion of cotton meal increased linoleic and stearic acids in fat deposits. Grass-based diets increased C 18:0 and C 18:3 in lamb tissues. Melting point of both SC and PR were strongly associated with differences in C 18:0 percentages. This approach underlined difficulties in understanding the diet effects on fatty acid composition of fat deposits and muscles without taking feeding and other management aspects into account. This study supported the extent to the modification of the fatty acid composition of lamb carcasses by choice of dietary ingredients despite the ruminal hydrogenation of dietary fat.

Effects of Nutritional Factors on Regular Cropping of Apple

Nutritional status of apple (Malus domestica Borkh.) trees may influence regularity of cropping through effects of some nutrient elements at various stages of the floral initiation, development, pollination, fertilization and fruit setting process. Other elements may influence regularity of cropping more indirectly as consequences of their effects on physiological processes or by modifying the sensitivity of the tree to adverse environmental factors. This report provides a brief summary of reported impacts of mineral nutrition on regularity of cropping.

Effects of Nutritional Factors on Regular Cropping of Apple

Any mineral nutrient deficiency or toxicity that adversely influences the normal biochemical and physiological processes in the tree can be expected to impact regularity of cropping. Deficiency of N limits growth and flowering of young trees and increases potential for biennial bearing in mature trees while excess N may stimulate excessive vegetative growth that results in shading of spurs and development of weak flowers with reduced set potential. B, Zn, and Cu shortages influence regularity of cropping through effects on flower development, pollination and/or fertilization. Effects of K, Mg, Mn, Fe, or S appear to be indirect, principally as consequences of limited carbohydrate production/availability. Crop load/vegetative growth relationships in one season can exert significant influences on nutrient status within the tree that may influence potential for cropping in the next season. Environmental stress may limit nutrient availability of various nutrient elements at critical times during the flower development and fruit setting sequence. Effects of nutritional factors on regularity of cropping must be considered in relation to their interaction with all other components of the fruit production system. Maintaining appropriate essential mineral nutrient supply and availability to avoid potential deficiencies or toxicities is critical to regular cropping of apple trees.

Transmucosal passage of bacteria across rat intestinal epithelium in the Ussing chamber: effect of nutritional factors and bacterial virulence.

Transmucosal passage of bacteria across the intestine, the essential and prerequisite step for bacterial translocation, cannot be effectively studied using in vivo models of translocation. We have adapted the Ussing chamber into a fresh, sterile organ culture system that can facilitate the study of bacterial-epithelial interactions. Intestinal membranes were mounted in the Ussing chamber and perfused with a solution rich in putative mucosal micronutrients. The transmembrane potential difference was constantly monitored as a marker of intestinal integrity. Transmucosal passage of various bacteria across the normal intestinal epithelium was quantitated, and the mucosal membrane was examined by light and transmission electron microscopy. The addition of potassium cyanide to the mucosal perfusate resulted in an irreversible loss of potential difference. Oxygen deprivation also led to a precipitous drop in potential difference, but it was reversible with prompt reoxygenation. In contrast, intestinal membranes perfused with a solution consisting of Dulbecco's modified Eagle's medium + 20 mM glutamine maintained their potential difference for a sustained period (>180 min). Both the viability and structural integrity of the ileal intestinal membrane were maintained in culture ex vivo using this perfusate. Qualitative differences were observed in the mechanism of transmucosal passage of mild to moderately virulent bacteria such as Escherichia coli C-25 and Proteus mirabilis M-13, which pass through the intestinal epithelium without causing overt damage to the mucosa, and more virulent organisms such as Salmonella typhimurium, which cause extensive mucosal damage by light and transmission electron microscopy. The Ussing system should provide a useful model of intact organ culture for the study of the mechanisms of bacterial translocation and the pathogenesis of enteric infections.

4.P.118 Lipid, apolipoprotein, glucose and insulin level alterations in obese men: Effect of nutritional factors

4.P.118 Lipid, apolipoprotein, glucose and insulin level alterations in obese men: Effect of nutritional factors

Studies on effects of nutritional factors on bone structure and osteoporosis in laying hens

1. A modern hybrid strain of laying hen (Hisex) was fed from point of lay to 68 weeks on a control diet and diets containing oystershell, fluoride, 1,25‐dihydroxycholecalciferol, ascorbic acid, a lower concentration of phosphorus and a combination of a lower concentration of crude protein and higher concentration of vitamin K. Hens from a much older strain (Brown Leghorn J‐line) were fed on the control diet. 2. Plasma variables were measured during lay. End‐of‐lay trabecular and medullary bone volumes in the proximal tarsometatarsus and free thoracic vertebra were measured by histomorphometry. 3. The majority of Hisex hens were considered to be osteoporotic by the end of lay. In contrast, none of the J‐line were osteoporotic. 4. None of the nutritional treatments affected trabecular bone volumes. Medullary bone volumes were increased significantly by feeding oystershell or fluoride. 5. There was no phenotypic correlation between egg production and trabecular bone volume in the Hisex hens. 6. The experiment provided evidence that osteoporosis in laying hens, as assessed by trabecular bone volumes, is not caused by calcium deficiency and could not be prevented by any of the nutritional treatments studied.

Exploring the role of diet in modifying the effect of known disease determinants: application to risk factors of liver cirrhosis.

The analysis of the combined effects of nutritional factors with other putative disease determinants in log-linear or logistic models is methodologically complicated by the strong multicollinearity between nutritional factors, resulting in poor precision in estimating the parameters. Furthermore, the generally used multiplicative structure is not always the most appropriate for describing the resulting joint effect of two or more factors on the disease risk. The authors addressed such problems in a case-control study assessing the interactions between alcohol intake, chronic hepatitis C virus (HCV) infection, and nutrient intake on the risk of liver cirrhosis. During the period from November 1989 to May 1990, 282 patients admitted to the medical departments of the hospitals of the Province of L'Aquila (central Italy) were enrolled: 115 cirrhotic patients aged 24-82 years (78 of whom were males) hospitalized because of liver decompensation, and 167 control patients aged 25-84 years (100 of whom were males) admitted to the same hospitals for acute diseases unrelated to alcohol intake, infection with hepatotropic viruses, and nutrition. No dose-effect relation was found between the intake of any nutrient and the risk of cirrhosis using classical methods. The analysis of principal components showed, however, that a pattern of higher lipid but lower protein and carbohydrate intakes was significantly associated with the risk of cirrhosis. The Breslow and Storer parametric family of relative risk functions showed that a multiplicative structure was the most adequate to describe the joint effect of nutritional pattern with alcohol intake and/or chronic HCV infection, whereas an additive structure best described the joint effect of chronic HCV infection and alcohol intake. In conclusion, the analysis of principal components and the Breslow and Storer family are useful tools to explore the role of diet on disease risk when precise pathogenic knowledge is not available. As an original finding, the authors suggest that a higher lipid intake, combined with lower protein and carbohydrate intakes, modifies multiplicatively the risk of cirrhosis associated with alcohol intake and/or chronic HCV infection.

Effects of nutritional factors on reproduction, growth, preweaning reflex development and postweaning learning performance in SHRSP.

1. Dietary high protein intake in stroke-prone spontaneously hypertensive rats (SHRSP) induces a reduction of blood pressure and decreases the incidence of cerebral lesion. The objective of this investigation was to determine the effects of nutritional factors of dietary high protein on reproduction, growth, preweaning reflex development, postweaning behaviour and learning performance in SHRSP. 2. SHRSP were fed on a high protein rat diet (OA2 diet) and a standard rat diet for SHRSP (FSP diet). Rats were mated by brother-sister combinations and observed on reproductive performance, preweaning reflex development and postweaning learning performance among the 3rd to the 6th generations. 3. OA2 showed some advanced responses at the preweaning period compared to FSP in the surface righting, negative geotaxis and mid-air righting reflexes. 4. At the postweaning period, hyperactivity of OA2 was indicated at the open field test. In the ambulatory activity of the circadian rhythm, OA2 was better synchronized with running activity in the light and dark alternation cycle. 5. OA2 group indicated the higher postweaning learning performance in the water E, the water multiple T (Biel) and the Morris water-maze test as well as the acquisition of the conditioned avoidance response test. 6. In conclusion, dietary high protein intake in SHRSP produced some advanced effects on preweaning reflex development and postweaning learning performance.

Effect of nutritional factors on lipase biosynthesis by Aspergillus niger

Lipase biosynthesis occured in medium without lipids, but for improved production an inducer was needed. The source and concentration of an inducer had no signifficant effect. Starch as an additional carbon source stimulated lipase biosynthesis when used in small amounts. Addition of NH4NO3 as a nitrogen source, KH2PO4 as a phosphate source as well as Mg ions to the medium with inital pH 5.0 gave the best yield.

Introduction to Effects of Nutritional Factors and the Microenvironment on Mucosal Immune Function

Introduction to Effects of Nutritional Factors and the Microenvironment on Mucosal Immune Function

Death of serum-free mouse embryo cells caused by transforming growth factor beta 1 and effects of nutritional factors.

Transforming growth factor beta 1 (1 ng/ml) caused death of serum-free mouse embryo cells cultured in a medium consisting of a 1:1 mixture of Dulbecco's Modified Eagle's medium and Ham's F12 medium supplemented with fibronectin, insulin, transferrin, epidermal growth factor, and high density lipoprotein. Cell death occurred in the presence of polyunsaturated fatty acids including linoleic acid in the absence of selenium. The death could be reversed by adding alpha-tocopherol to the culture indicating a mechanism involving fatty acid peroxidation. Butylated hydroxytoluene was a poor suppressor of cell death in contrast to alpha-tocopherol. High density lipoprotein and fatty acid-free albumin also suppressed cell death at the level of 20 micrograms/ml and 1 mg/ml, respectively. Transforming growth factor beta 1 also caused a low rate of cell growth after heat treatment of the cells at 45 degrees C.

Glucose Regulation of Growth Hormone Receptors in Primary Cultured Rat Hepatocytes*

The effects of nutritional factors on the regulation of GH receptors were studied by measuring the specific binding of 125I-human GH to rat hepatocytes cultured in various media. The binding of labeled GH to primary cultured hepatocytes decreased during culture, the extent of the decrease depending on the culture medium. The decreases of GH binding during culture in glucose-poor media (i.e. Williams' medium E, Dulbecco's modified minimum essential medium, and McCoy 5A medium) were significantly more than that in glucose-rich Waymouth's medium MB 752/1 (Waymouth's). In glucose-poor media supplemented with glucose, the extent of decrease of GH binding was comparable to that in Waymouth's. Other hexoses such as D-fructose and D-mannose also significantly reduced the decrease in GH binding. Scatchard plot analysis showed that the effect of glucose in preventing decrease of GH binding was due to change in the number of binding sites without significant change in their affinity. The effect of glucose was additive with that of dexamethasone, which induces GH receptors. Cycloheximide caused almost complete loss of GH binding by cells cultured in the presence of glucose. 2-Deoxyglucose reduced the effect of glucose, but did not affect that of dexamethasone. These results show that glucose counteracts decrease of GH binding sites during culture and suggest that it affects de novo synthesis of GH receptors, presumably through glycosylation of a certain protein that regulates GH receptor gene expression (new protein synthesis). The mechanism of the effect of glucose on induction of GH receptors seems to be different from that of dexamethasone.

Nutritional Factors and Antimicrobials on Development of Infective Larvae of Subperiodic Brugia malayi (Nematoda: Filarioidea) in Anopheles quadrimaculatus and Aedes aegypti (Diptera: Culicidae)

The effects of nutritional factors and antimicrobials on the development of infective larvae of subperiodic Brugia malayi in susceptible Anopheles quadrimaculatus Say and Aedes aegypti (L.) were investigated. Larvae of both species of mosquitoes were reared on brewers yeast or a 1:1 brewers yeast-liver powder mixture. After emergence, one-half of the adults from each rearing condition were maintained on a 10% sucrose solution and the other half on a 10% sucrose solution containing 0.1% p-aminobenzoic acid (PABA). Females of both species of mosquitoes that fed on B. malayi-infected jirds showed a significant increase in the ineffective rate and intensity of infectiveness when the mosquito larvae were reared on the brewers yeast-liver powder diet. The addition of 0.1% PABA to the adult diet increased numbers of infective larvae of B. malayi that developed in Ae. aegypti but not in An. quadrimaculatus. The intensity of infectiveness of B. malayi was significantly greater when An. quadrimaculatus females were provided with a second blood meal from an uninfected jird and when females of both species were maintained on different concentrations of an antimicrobial solution.

Production of iridoid glucosides in cell suspension cultures of Penstemon serrulatus: effects of nutritional factors

The cell growth and iridoid production were studied in suspension cultures derived from anther-callus of Penstemon serrulatus. Penstemide and serrulatoloside were major iridoids produced by the cell cultures. Cells (14 days old) produced up to 7.8% of dry weight of penstemide and 5.1% of serrulatoloside. However, formation of both iridoids gradually decreased during consecutive growth cycles. It was possible to improve the quantity of penstemide and serrulatoloside in cell cultures by altering the concentrations of some nutritional factors in the medium. The best results were obtained by increasing the concentration of sucrose (to 5% or 7%); the contents of penstemide and serrulatoloside were 4-fold higher than those obtained in the presence of 3% sucrose. Sucrose concentration from 5% to 7% improved not only the content of iridoids, but also cell growth. Further stimulation of iridoid production was achieved by the selection of high iridoid-producing cell line and transferring the cells to optimized medium.

栄養条件と細胞性免疫に関する研究

栄養条件と細胞性免疫に関する研究