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Title:
A Short History of Nutritional Science: Part 1 (1785-1885)
Authors:
Carpenter, Kenneth J.
Abstract:
Published:
2003
Title:
A Short History of Nutritional Science: Part 2 (1885-1912)
Authors:
Carpenter, Kenneth J.
Abstract:
Published:
2003
Title:
A Short History of Nutritional Science: Part 3 (1912-1944)
Authors:
Carpenter, Kenneth J.
Abstract:
Published:
2003
Title:
A Short History of Nutritional Science: Part 4 (1945-1985)
Authors:
Carpenter, Kenneth J.
Abstract:
Published:
2003
Title:
Acetoacetate protects hippocampal neurons against glutamate-mediated neuronal damage during glycolysis inhibition
Authors:
Massieu, L.; Haces, M. L.; Montiel, T.; Hernández-Fonseca, K.
Abstract:
Glucose is the main substrate that fulfills energy brain demands. However, in some circumstances, such as diabetes, starvation, during the suckling period and the ketogenic diet, brain uses the ketone bodies, acetoacetate and beta-hydroxybutyrate, as energy sources. Ketone body utilization in brain depends directly on its blood concentration, which is normally very low, but increases substantially during the conditions mentioned above. Glutamate neurotoxicity has been implicated in neurodegeneration associated with brain ischemia, hypoglycemia and cerebral trauma, conditions related to energy failure, and to elevation of glutamate extracellular levels in brain. In recent years substantial evidence favoring a close relation between glutamate neurotoxic potentiality and cellular energy levels, has been compiled. We have previously demonstrated that accumulation of extracellular glutamate after inhibition of its transporters, induces neuronal death in vivo during energy impairment induced by glycolysis inhibition. In the present study we have assessed the protective potentiality of the ketone body, acetoacetate, against glutamate-mediated neuronal damage in the hippocampus of rats chronically treated with the glycolysis inhibitor, iodoacetate, and in hippocampal cultured neurons exposed to a toxic concentration of iodoacetate. Results show that acetoacetate efficiently protects against glutamate neurotoxicity both in vivo and in vitro probably by a mechanism involving its role as an energy substrate.
Published:
2003
Title:
An increase in dietary protein improves the blood glucose response in persons with type 2 diabetes
Authors:
Gannon, Mary C.; Nuttall, Frank Q.; Saeed, Asad; Jordan, Kelly; Hoover, Heidi
Abstract:
BACKGROUND In single-meal studies, dietary protein does not result in an increase in glucose concentrations in persons with or without type 2 diabetes, even though the resulting amino acids can be used for gluconeogenesis. OBJECTIVE The metabolic effects of a high-protein diet were compared with those of the prototypical healthy (control) diet, which is currently recommended by several scientific organizations. DESIGN The metabolic effects of both diets, consumed for 5 wk each (separated by a 2-5-wk washout period), were studied in 12 subjects with untreated type 2 diabetes. The ratio of protein to carbohydrate to fat was 30:40:30 in the high-protein diet and 15:55:30 in the control diet. The subjects remained weight-stable during the study. RESULTS With the fasting glucose concentration used as a baseline from which to determine the area under the curve, the high-protein diet resulted in a 40% decrease in the mean 24-h integrated glucose area response. Glycated hemoglobin decreased 0.8% and 0.3% after 5 wk of the high-protein and control diets, respectively; the difference was significant (P \textless 0.05). The rate of change over time was also significantly greater after the high-protein diet than after the control diet (P \textless 0.001). Fasting triacylglycerol was significantly lower after the high-protein diet than after the control diet. Insulin, C-peptide, and free fatty acid concentrations were not significantly different after the 2 diets. CONCLUSION A high-protein diet lowers blood glucose postprandially in persons with type 2 diabetes and improves overall glucose control. However, longer-term studies are necessary to determine the total magnitude of response, possible adverse effects, and the long-term acceptability of the diet.
Published:
2003
Title:
Anaemia and vitamin A deficiency in poor urban pregnant women of Bangladesh
Authors:
Ahmed, Faruk; Mahmuda, Ismat; Sattar, Abeda; Akhtaruzzaman, Md
Abstract:
This cross-sectional study investigated the prevalence of anaemia and vitamin A deficiency (VAD) among pregnant women in a poor urban population of Bangladesh. It also examined the association of various socio-economic and dietary factors with anaemia and vitamin A status. A maternal and child health clinic in Dhaka city, Bangladesh was used to obtain the sample. Three hundred and eighty three pregnant women, aged 20-30 years, of 20-30 weeks gestation were randomly selected from women on their first presentation for antenatal care. Socio-economic, pregnancy related information, usual dietary pattern and anthropometric data were collected. Blood haemoglobin and serum retinol (vitamin A) concentrations were determined. About 40% of the pregnant women were anaemic (haemoglobin <11.0 g/dl) and 45% had low serum vitamin A levels (<30 microg/dl); with 8.6% having sub-clinical VAD (serum retinol
Published:
2003
Title:
Ancient teeth and modern human origins: an expanded comparison of African Plio-Pleistocene and recent world dental samples
Authors:
Irish, J. D; Guatelli-Steinberg, D.
Abstract:
Published:
2003
Title:
Bioavailability of iron, zinc, and other trace minerals from vegetarian diets
Authors:
Hunt, Janet R.
Abstract:
Iron and zinc are currently the trace minerals of greatest concern when considering the nutritional value of vegetarian diets. With elimination of meat and increased intake of phytate-containing legumes and whole grains, the absorption of both iron and zinc is lower with vegetarian than with nonvegetarian, diets. The health consequences of lower iron and zinc bioavailability are not clear, especially in industrialized countries with abundant, varied food supplies, where nutrition and health research has generally supported recommendations to reduce meat and increase legume and whole-grain consumption. Although it is clear that vegetarians have lower iron stores, adverse health effects from lower iron and zinc absorption have not been demonstrated with varied vegetarian diets in developed countries, and moderately lower iron stores have even been hypothesized to reduce the risk of chronic diseases. Premenopausal women cannot easily achieve recommended iron intakes, as modified for vegetarians, with foods alone; however, the benefit of routine iron supplementation has not been demonstrated. It may be prudent to monitor the hemoglobin of vegetarian children and women of childbearing age. Improved assessment methods are required to determine whether vegetarians are at risk of zinc deficiency. In contrast with iron and zinc, elements such as copper appear to be adequately provided by vegetarian diets. Although the iron and zinc deficiencies commonly associated with plant-based diets in impoverished nations are not associated with vegetarian diets in wealthier countries, these nutrients warrant attention as nutritional assessment methods become more sensitive and plant-based diets receive greater emphasis.
Published:
2003
Title:
Biologic and methodologic issues for nutritional biomarkers
Authors:
Potischman, Nancy
Abstract:
Nutritional biomarkers are used for a variety of purposes in large-scale population surveys and epidemiologic studies as well as smaller clinical studies. The main reasons for using nutritional biomarkers are to provide measures of nutritional status that have less error than dietary data, nutrient status for nutrients with inadequate dietary data, to obtain a more proximal and integrated assessment of nutrient status that incorporates metabolism, to assess dietary change and compliance in intervention studies, and dietary intake for the validation of dietary questionnaires. However, often there is oversight by the investigators regarding biologic and laboratory issues, which have implications for the utility of nutritional biomarkers. This article reviews some of the physiologic issues that contribute to between-person variability in nutrient status and the utility and meaning of specimens from various body compartments. Issues related to the collection and storage of biologic specimens are addressed, although it is recommended that investigators contact laboratory colleagues at the beginning of any study for updated information. The necessity for blind quality surveillance of laboratory analyses beyond the normal procedures employed by collaborating laboratories also is addressed. The advantages and disadvantages of nutritional biomarkers are reviewed, especially in comparison with using dietary methodology.
Published:
2003
Title:
Biomarkers of fat and fatty acid intake
Authors:
Arab, Lenore
Abstract:
Unlike other macronutrients such as protein, the amounts and types of fat in the human diet vary tremendously across cultures and over time have changed significantly within Westernized countries. Studies of the effect that fat sources, fat amounts and changes in fat intake have on human disease are extremely difficult to conduct with traditional dietary assessment methods for a number of reasons. These include the hidden nature of many fats, the variation in fatty acids contained in foods and feed and the sensitivity of individuals to questions about fat intake in their diets. For these reasons biomarkers of fat intake are particularly desirable. Fat and fat-soluble substances have the advantages over other nutrients of a long half-life and readily accessible storage depots (in the absence of starvation, undernutrition or eating disorders). Technological advances in quantitative measurements of individual fatty acids, with the help of gas chromatography and mass spectrometry (GCMS)((3)) and high performance liquid chromatography (HPLC), made possible the study of specific isomers of minor fatty acids from small tissue samples. Technological advances also opened the gateways to the study of fats that represent less than 1% of the total fat profiles, such as decosahexanoic acid (DHA), eicosapentanoic acid (EPA) and conjugated linoleic acid (CLA). Biological advances enhanced our appreciation of the differences between fats of differing chain lengths within a family, including the saturated fats. Challenges remain, such as assessing total fat intake, discriminating the contribution of endogenously produced fats, determining how to evaluate the importance of relative versus absolute contributions of fat and accounting for the factors that influence deposition and mobilization of individual fats within and between individuals. Factors that can influence deposition and mobilization include genetic variation, disease status, lifestyle differences (i.e., alcohol consumption and smoking), circulating apolipoprotein levels and the hormonal milieu of the individual and the source tissue.
Published:
2003
Title:
Biomarkers of nutrient exposure and status in one-carbon (methyl) metabolism
Authors:
Mason, Joel B.
Abstract:
One-carbon metabolism is a network of interrelated biochemical reactions that involve the transfer of one-carbon groups from one compound to another. The coenzymes necessary for several of these reactions include the B-vitamins, folate, vitamin B-12, vitamin B-6 and riboflavin (vitamin B-2), whereas important intermediary compounds in this schema include methionine and choline. There has been renewed interest in one-carbon metabolism during the past several years, engendered by recent insights that indicate that modest dietary inadequacies of the abovementioned nutrients, of a degree insufficient to cause classical deficiency syndromes, can still contribute to important diseases such as neural tube defects, cardiovascular disease and cancer. Traditional means of assessing nutrient exposure with food frequency questionnaires, and nutrient status with plasma and urine vitamin assays, has some genuine validity and utility. Assessing the concentration of appropriate intermediary compounds, such as plasma homocysteine for folate and methylmalonic acid for vitamin B-12, provides further insights because they appear to add a degree of sensitivity that does not exist with the more traditional assays. There may also be value in developing measures that integrate the status of all these nutrients and express it as a functional "methylation capacity" of the individual. Plasma or tissue concentrations of S-adenosylmethionine and S-adenosylhomocysteine, and genomic DNA methylation are two potential candidates in this regard although much work is yet to be done to define the nature of these relationships.
Published:
2003
Title:
Bittersweet: diabetes, insulin, and the transformation of illness
Authors:
Feudtner, John Christopher
Abstract:
"One of medicine's most remarkable therapeutic triumphs was the discovery of insulin in 1921. The drug produced astonishing results, rescuing children and adults from the deadly grip of diabetes. But as Chris Feudtner demonstrates, the subsequent transformation of the disease from a fatal condition into a chronic illness is a story of success tinged with irony, a revealing saga that illuminates the complex human consequences of medical intervention." "Bittersweet chronicles this history of diabetes through the compelling perspectives of people who lived with this disease. Drawing on a remarkable body of letters exchanged between patients or their parents and Elliot P. Joslin and the staff of physicians at his famed Boston clinic, Feudtner examines the experience of living with diabetes across the twentieth century, highlighting changes in treatment and their profound effects on patients' lives. Although focused on juvenile-onset, or Type 1, diabetes, the themes explored in Bittersweet have implications for our understanding of adult-onset, or Type 2, diabetes, as well as a host of other diseases that are being transformed by drugs or medical devices from acute to chronic conditions. Indeed, the tale of diabetes in the post-insulin era provides an ideal opportunity for exploring the larger questions of how medicine changes our lives."--Jacket.
Published:
2003
Title:
CLINICAL CALORIMETRY XLV. PROLONGED MEAT DIETS WITH A STUDY OF KIDNEY FUNCTION AND KETOSIS
Authors:
McClellan, Walter S.; Bois, Eugene F. Du
Abstract:
Introduction ............................... ...... ........ . . 651 Literature .................................. ...... ........ . . 652 Plan of investigation ....................... ...... ........ . . 653 Protocols ................................... ...... ........ . . 653 Nature of diet ............................ ........ . 655 Effect of diet on clinical condition .......... ...... ........ . . 659 Effect of diet on urinary constituents ....... ...... ........ . 662 Effect of diet on kidneys .................... ...... ........ . 663 Effect of diet on fat metabolism ............ . . . . . . . . . . . . . . . . 664 Summary and conclusions .................. ...... ........ . . 666 Bibliography ............................... ...... ........ . . 667
Published:
2003
Title:
Calcium balance in young adults on a vegan and lactovegetarian diet
Authors:
Kohlenberg-Mueller, Kathrin; Raschka, Ladislav
Abstract:
For people in Western countries, the vegan diet has the advantage of low energy intake, but the calcium status of this strictly plant-based diet is still unclear. The aim of this study was to determine the calcium balance of individuals on a vegan diet in comparison with a lactovegetarian diet in a short-term investigation. Seven women and one man, ranging in age from 19 to 24 years, received during the first 10 days a vegan diet based on plant foods and calcium-rich mineral water and a lactovegetarian diet during the following 10 days. Portion size was adapted to the subjects' individual energy requirements. Calcium status was assessed by means of calcium intake in food and calcium output in feces and urine as measured by flame atomic absorption spectrophotometry. In addition, deoxypyridinoline was measured in urine as a marker of bone resorption. The results show a significantly smaller daily calcium intake with an average of 843 +/- 140 mg in the vegan versus 1322 +/- 303 mg in the lactovegetarian diet. Apparent calcium absorption rates were calculated as 26% +/- 15% in the vegan and 24% +/- 8% in the lactovegetarian group (NS). The calcium balance was positive both in the vegan diet (119 +/- 113 mg/day) and in the lactovegetarian diet (211 +/- 136 mg/day) (NS). Deoxypyridinoline excretion showed no significant difference between the two diets (105 +/- 31 and 98 +/- 23 nmol/day). The present results indicate that calcium balance and a marker of bone turnover are not affected significantly when calcium is provided either solely by plant foods or by a diet including dairy products, despite the significantly different calcium intake levels in the diets. We conclude that a well-selected vegan diet maintains calcium status, at least for a short-term period.
Published:
2003
Title:
Can randomised trials rely on existing electronic data? A feasibility study to explore the value of routine data in health technology assessment.
Authors:
Williams, J. G.; Cheung, W. Y.; Cohen, D. R.; Hutchings, H. A.; Longo, M. F.; Russell, I. T.
Abstract:
Published:
2003
Title:
Clinical Implications of Thermal Therapy in Lifestyle-Related Diseases
Authors:
Biro, Sadatoshi; Masuda, Akinori; Kihara, Takashi; Tei, Chuwa
Abstract:
Systemic thermal therapy, such as taking a warm-water bath and sauna, induces systemic vasodilation. It was found that repeated sauna therapy (60 degrees C for 15 min) improved hemodynamic parameters, clinical symptoms, cardiac function, and vascular endothelial function in patients with congestive heart failure. Vascular endothelial function is impaired in subjects with lifestyle-related diseases, such as hypertension, hyperlipidemia, diabetes mellitus, obesity, and smoking. Sauna therapy also improved endothelial dysfunction in these subjects, suggesting a preventive role for atherosclerosis. In animal experiments, sauna therapy increases mRNA and protein levels of endothelial nitric oxide synthase (eNOS) in aortas. In normal-weight patients with appetite loss, repeated sauna therapy increased plasma ghrelin concentrations and daily caloric intake and improved feeding behavior. In obese patients, the body weight and body fat significantly decreased after 2 weeks of sauna therapy without increase of plasma ghrelin concentrations. On the basis of these data, sauna therapy may be a promising therapy for patients with lifestyle-related diseases.
Published:
2003
Title:
Delayed-Onset Hypothesis of Antipsychotic Action
Authors:
Agid, Ofer; Kapur, Shitij; Arenovich, Tamara; Zipursky, Robert B
Abstract:
Published:
2003
Title:
Dipeptidyl aminopeptidases in health and disease: Preface
Authors:
Klapp, Burghard F.; Hildebrandt, Martin
Abstract:
"Proceedings of the International Conference on Dipeptidyl Aminopeptidases, held September 26-28, 2002, in Berlin, Germany"–Title page verso. Dipeptidyl Aminopeptidases exert a potent modulatory role at an interface between immune mechanisms, metabolic responses and neuroendocrine pathways. This volume presents a state-of-the-art view on these enzymes. Structure and function of dipeptidyl aminopeptidases – DPP IV-like enzymes – Immune mechanisms and immune disorders – Angiogenesis and cancer – Diabetes and metabolism.
Published:
2003
Title:
Effects of protein vs. carbohydrate-rich diets on fuel utilisation in obese women during weight loss
Authors:
Labayen, Idoia; Díez, Nieves; González, Alvaro; Parra, Dolores; Martínez, J. Alfredo
Abstract:
BACKGROUND: Energy restriction is a common therapeutic approach for weight reduction, but the most effective macronutrient distribution of the hypoenergetic diet as well as the role of the metabolic processes involved require further investigations. OBJECTIVE: To study the effect of a high protein (HP) hypoenergetic diet compared with a high carbohydrate (HC) hypoenergetic diet on fuel utilisation changes during the weight loss process in obese women. DESIGN: Eleven obese (BMI>30) women were randomly assigned to a 10w dietary intervention study comparing HP (30% protein) or HC (55% carbohydrate) energy restricted diets providing 30% energy fat content. Substrate utilisation was evaluated by indirect calorimetry. Body weight and composition (Bod Pod) and blood measurements were performed before and after weight loss. RESULTS: On average, the individuals on the HP dietary group lost 4.4 kg more than those in the HC program (p<0.50), which was mainly due to a fat mass loss (3.7 kg, p<0.05) with no statistical differences in lean body mass reduction. These losses were accompanied by a significant decrease in fasting leptin in the HP group (-52%; P
Published:
2003
Title:
Efficacy and safety of thermal vasodilation therapy by sauna in infants with severe congestive heart failure secondary to ventricular septal defect
Authors:
Sugahara, Yoko; Ishii, Masahiro; Muta, Hiromi; Egami, Kimiyasu; Akagi, Teiji; Matsuishi, Toyojiro
Abstract:
In isolated ventricular septal defect (VSD), surgical repair provides exellent results with a low mortality rate. However, the operative risk may be higher in infants, given the neurologic consequences of circulatory arrest. In addition, the risk of hepatitis from blood transfusion for cardioplasia bypass still exists. The hemodynamic improvement produced by vasodilators such as angiotensin-converting enzyme inhibitors provides great therapeutic benefit to adult and pediatric patients with congestive heart failure (CHF). The use of vasodilators in infants with CHF, particularly when caused by a large left-to-right shunt that results from a VSD, is controversial. The symptoms of CHF caused by pulmonary circulatory congestion in these infants sometimes worsens despite use of the vasodilator; the vasodilator may cause an excessive decline in pulmonary vascular resistance and an increase in left-to-right shunt volume. It has recently been reported that thermal vasodilation improved acute hemodynamics in adult patients with CHF. Sauna bathing is believed to be a better method of body warming, because it can be applied without increased external hydrostatic pressure and increases venous return during heat exposure. We assessed the efficacy and safety of thermal vasodilation therapy by far-infrared ray dry sauna in infants with severe CHF caused by VSD.
Published:
2003
Title:
Epidemiologists Explain Pellagra: Gender, Race, and Political Economy in the Work of Edgar Sydenstricker
Authors:
Marks, Harry M.
Abstract:
Published:
2003
Title:
Evolutionary trends and the origin of the mammalian lower jaw
Authors:
Sidor, C. A.
Abstract:
The single bony element forming the lower jaw of living mammals, the dentary, has been interpreted as representing the culmination of a long and gradual evolutionary trend. Numerous fossil nonmammalian synapsids ("mammal-like reptiles") show varying degrees of enlargement of the dentary and concomitant reduction in the postdentary bones. To quantitatively reexamine patterns of morphological change in the evolution of the mammalian lower jaw, measurement and discrete character data were collected from 322 fossil synapsid mandibles spanning Late Carboniferous through Jurassic time. Measurements confirm that the relative contribution of the dentary increased in theriodont (advanced therapsid) evolution with regard to both stratigraphic and phylogenetic position. However, dentary enlargement and postdentary reduction failed to typify all therapsid subclades. Qualitative characters of the mandible were used to quantify morphological similarity with regard to the early mammal Morganucodon. Analyses contrasting stratigraphic and phylogenetic position with mammalian similarity indicate that mandibular evolution was primarily conservative, with only anomodont therapsids evolving substantial morphological novelty. Scaling analyses comparing the area of the dentary and postdentary regions to jaw length uniformly show isometry or slight positive allometry, although cynodont therapsids have a smaller postdentary region than any other therapsid subgroup. These results suggest that body size decreases cannot fully explain the reduction of the postdentary bones. Finally, step size bias was tested as a mechanism for explaining long-term trends. Qualitative data reveal no significant difference in the magnitude of character changes occurring in mammalian and nonmammalian directions.
Published:
2003
Title:
Food in early modern Europe
Authors:
Albala, Ken
Abstract:
This unique book examines food's importance during the massive evolution of Europe following the Middle Ages.
Published:
2003
Title:
Food safety and risk assessment: naturally occurring potential toxicants and anti-nutritive compounds in plant foods
Authors:
Sanders, Thomas A. B.
Abstract:
The centralisation and globalisation of the world food supply presents opportunities for massive epidemics of food borne illness. Food processing generally decreases exposure to naturally occurring toxicants. A significant number of deaths are caused in both developed and developing countries from the consumption of naturally occurring toxicants and this exceeds the numbers attributable to artificial food contaminants and pollutants. The risk posed by naturally occurring toxicants is greater in developing countries where food choice and facilities for food processing are limited. The main risk in developed countries is from food important from areas where food safety controls are inadequate. Toxins derived from marine algae present a specific threat to health especially as seafood is being traded from areas where poisoning by algal toxins is known to occur. A systematic approach to food safety using HACCP methodology and identity preservation of the food are crucial in the prevention of food related illness. There is also a need for international agreed standards for tolerable levels of naturally occurring toxicants in foodstuffs but these should derived not be set unreasonably low as this would threaten food security in developing countries. The occurrence of a number of fatalities in developing countries among people consuming herbal teas and dietary supplements underscores the need to assess the safety of these products before they are placed on the market.
Published:
2003
Title:
From plain fare to fusion food: British diet from the 1890s to the 1990s
Authors:
Oddy, Derek J
Abstract:
"Simple meals made from a limited range of industrially processed foodstuffs constituted the 'plain fare' which most people in Britain ate from the 1890s until after the Second World War. Dietary surveys show that when wages were low and social conditions poor, health was affected, and support the view that malnutrition and dietary deficiencies existed during the first half of the twentieth century. Increasing knowledge of essential nutrients such as vitamins brought scientists into conflict with civil servants, particularly during the Great War and the depression of the interwar years." "Wars put great strains on Britain's supplies of food, much of which was imported. In the Great War, civilians suffered unjustifiably before food rationing was finally introduced. The widely held view that the science of nutrition informed government policy in the Second World War is shown to be a myth, since dietary inequalities continued and, by the mid-1940s, children's growth was affected."--Jacket.
Published:
2003
Title:
Gastrointestinal Satiety Signals I. An overview of gastrointestinal signals that influence food intake
Authors:
Woods, S. C.
Abstract:
An overview is presented of those signals generated by the gastrointestinal (GI) tract during meals that interact with the central nervous system to create a sensation of fullness and satiety. Although dozens of enzymes, hormones, and other factors are secreted by the GI tract in response to food in the lumen, only a handful are able to influence food intake directly. Most of these cause meals to terminate and hence are called satiety signals, with CCK being the most investigated. Only one GI signal, ghrelin, that increases meal size has been identified. The administration of exogenous CCK or other satiety signals causes smaller meals to be consumed, whereas blocking the action of endogenous CCK or other satiety signals causes larger meals to be consumed. Satiety signals are relayed to the hindbrain, either indirectly via nerves such as the vagus from the GI tract or else directly via the blood. Most factors that influence how much food is eaten during individual meals act by changing the sensitivity to satiety signals. This includes adiposity signals as well as habits and learning, the social situation, and stressors.
Published:
2003
Title:
Goldberger's war: the life and work of a public health crusader
Authors:
Kraut, Alan M
Abstract:
Chronicles the works of the U.S. Public Health Service champion, including his early twentieth-century campaign against the epidemics of the time and a political struggle to prove that pellagra was caused by a dietary deficiency.
Published:
2003
Title:
How to Eat Like a Gentleman: Dietetics and Ethics in Early Modern England
Authors:
Shapin, Steven
Abstract:
Published:
2003
Title:
Inflammatory Markers and Onset of Cardiovascular Events: Results from the Health ABC Study
Authors:
Cesari, Matteo; Penninx, Brenda W J H; Newman, Anne B.; Kritchevsky, Stephen B.; Nicklas, Barbara J.; Sutton-Tyrrell, Kim; Rubin, Susan M.; Ding, Jingzhong; Simonsick, Eleanor M.; Harris, Tamara B.; Pahor, Marco
Abstract:
BACKGROUND: Inflammation plays an important role in cardiovascular disease. The aim of this study is to investigate the predictive value of several inflammatory markers on the incidence of cardiovascular events in well-functioning older persons. METHODS AND RESULTS: The subjects were 2225 participants 70 to 79 years old, without baseline cardiovascular disease, who were enrolled in the Health, Aging, and Body Composition study. Incident coronary heart disease (CHD), stroke, and congestive heart failure (CHF) events were detected during an average follow-up of 3.6 years. Blood levels of interleukin-6 (IL-6), C-reactive protein (CRP), and tumor necrosis factor-alpha (TNF-alpha) were assessed. After adjustment for potential confounders, IL-6 was significantly associated with all outcomes (CHD events, per IL-6 SD increase: RR, 1.27; 95% CI, 1.10 to 1.48; stroke events, per IL-6 SD increase: RR, 1.45; 95% CI, 1.12 to 1.86; CHF events, per IL-6 SD increase: RR, 1.72; 95% CI, 1.40 to 2.12). TNF-alpha showed significant associations with CHD (per TNF-alpha SD increase: RR, 1.22; 95% CI, 1.04 to 1.43) and CHF (per TNF-alpha SD increase: RR, 1.59; 95% CI, 1.30 to 1.95) events. CRP was significantly associated with CHF events (per CRP SD increase: RR, 1.48; 95% CI, 1.23 to 1.78). A composite summary indicator of inflammation showed a strong association with incident cardiovascular events, with an especially high risk if all 3 inflammatory markers were in the highest tertile. CONCLUSIONS: Findings suggest that inflammatory markers are independent predictors of cardiovascular events in older persons.
Published:
2003
Title:
Intracellular and extracellular roles of S100 proteins
Authors:
Donato, Rosario
Abstract:
S100, a multigenic family of non-ubiquitous Ca2+-modulated proteins of the EF-hand type expressed in vertebrates exclusively, has been implicated in intracellular and extracellular regulatory activities. Members of this protein family have been shown to interact with several effector proteins within cells thereby regulating enzyme activities, the dynamics of cytoskeleton constituents, cell growth and differentiation, and Ca2+ homeostasis. Structural information indicates that most of S100 proteins exist in the form of antiparallelly packed homodimers (in some cases heterodimers), capable of functionally crossbridging two homologous or heterologous target proteins in a Ca2+-dependent (and, in some instances, Ca2+-independent) manner. In addition, extracellular roles have been described for several S100 members, although secretion (via an unknown mechanism) has been documented for a few of them. Extracellular S100 proteins have been shown to exert regulatory effects on inflammatory cells, neurons, astrocytes, microglia, and endothelial and epithelial cells, and a cell surface receptor, RAGE, has been identified as a potential S100A12 and S100B receptor transducing the effects of these two proteins on inflammatory cells and neurons. Other cell surface molecules with ability to interact with S100 members have been identified, suggesting that RAGE might not be a universal S100 protein receptor and/or that a single S100 protein might interact with more than one receptor. Collectively, these data indicate that members of the S100 protein family are multifunctional proteins implicated in the regulation of a variety of cellular activities. Microsc. Res. Tech. 60:540–551, 2003. © 2003 Wiley-Liss, Inc.
Published:
2003
Title:
Iodine deficiency in vegetarians and vegans
Authors:
Krajcovicová-Kudlácková, M.; Bucková, K.; Klimes, I.; Seboková, E.
Abstract:
Iodine content in food of plant origin is lower in comparison with that of animal origin due to a low iodine concentration in soil. Urinary iodine excretion was assessed in 15 vegans, 31 lacto- and lacto-ovovegetarians and 35 adults on a mixed diet. Iodine excretion was significantly lower in alternative nutrition groups - 172 microg/l in vegetarians and 78 microg/l in vegans compared to 216 microg/l in subjects on a mixed diet. One fourth of the vegetarians and 80% of the vegans suffer from iodine deficiency (iodine excretion value below 100 microg/l) compared to 9% in the persons on a mixed nutrition. The results show that under conditions of alternative nutrition, there is a higher prevalence of iodine deficiency, which might be a consequence of exclusive or prevailing consumption of food of plant origin, no intake of fish and other sea products, as well as reduced iodine intake in the form of sea salt.
Published:
2003
Title:
Ketoacids? Good medicine?
Authors:
Cahill, George F.; Veech, Richard L.
Abstract:
D-beta-hydroxybutyrate, the principal "ketone" body in starving man, displaces glucose as the predominating fuel for brain, decreasing the need for glucose synthesis in liver (and kidney) and accordingly spares its precursor, muscle-derived amino acids. Thus normal 70 kg. man survives 2-3 months of starvation instead of several weeks, and obese man many months to over a year. Without this metabolic adaptation, H. sapiens could not have evolved such a large brain. Recent studies have shown that D-beta-hydroxybutyrate, the principal "ketone", is not just a fuel, but a "superfuel" more efficiently producing ATP energy than glucose or fatty acid. In a perfused rat heart preparation, it increased contractility and decreased oxygen consumption. It has also protected neuronal cells in tissue culture against exposure to toxins associated with Alzheimer's or Parkinson's. In a rodent model it decreased the death of lung cells induced by hemorrhagic shock. Also, mice exposed to hypoxia survived longer. These and other data suggest a potential use of beta-hydroxybutyrate in a number of medical and non-medical conditions where oxygen supply or substrate utilization may be limited. Efforts are underway to prepare esters of beta-hydroxybutyrate which can be taken orally or parenterally to study its potential therapeutic applications.
Published:
2003
Title:
Metabolic changes induced by regular submaximal aerobic exercise in meat-type rabbits
Authors:
Szabo, A.; Romvari, R.; Bogner, P.; Febel, Hedvig; Szendro, Zs
Abstract:
Pannon White growing rabbits (a group of 8) were exposed to treadmill exercise (3-9 m/s, 1.2-1.6 km/day) twice a day for 4 weeks, while additional 8 animals, kept inactive, were assigned as the control group. Weekly, 12 hours after exercise, venous blood was taken for serum metabolite and enzyme activity measurements. Total serum protein, albumin and creatinine levels significantly increased during the second half of the training, as compared to the control group. Triacylglycerol levels in the exercised group as compared to controls, however, were higher only after the first and the fourth weeks of the experiment. Resting non-esterified fatty acid (NEFA) concentration of the trained rabbits was lower at the end of the trial. On the other hand, there were no significant differences, as compared to the respective controls, in serum urea, total and HDL cholesterol levels. At the end of the exercise alkaline phosphatase activity was higher and total lactate dehydrogenase activity was lower in the trained rabbits. Serum alanine aminotransferase, aspartate aminotransferase and gamma-glutamyl transpeptidase activities were not changed, while creatine kinase activity was slightly lower in the trained group. The serum cortisol concentration was not different in the trained and control rabbits.
Published:
2003
Title:
Mitochondrial complex I inhibitor rotenone induces apoptosis through enhancing mitochondrial reactive oxygen species production
Authors:
Li, Nianyu; Ragheb, Kathy; Lawler, Gretchen; Sturgis, Jennie; Rajwa, Bartek; Melendez, J. Andres; Robinson, J. Paul
Abstract:
Inhibition of mitochondrial respiratory chain complex I by rotenone had been found to induce cell death in a variety of cells. However, the mechanism is still elusive. Because reactive oxygen species (ROS) play an important role in apoptosis and inhibition of mitochondrial respiratory chain complex I by rotenone was thought to be able to elevate mitochondrial ROS production, we investigated the relationship between rotenone-induced apoptosis and mitochondrial reactive oxygen species. Rotenone was able to induce mitochondrial complex I substrate-supported mitochondrial ROS production both in isolated mitochondria from HL-60 cells as well as in cultured cells. Rotenone-induced apoptosis was confirmed by DNA fragmentation, cytochrome c release, and caspase 3 activity. A quantitative correlation between rotenone-induced apoptosis and rotenone-induced mitochondrial ROS production was identified. Rotenone-induced apoptosis was inhibited by treatment with antioxidants (glutathione, N-acetylcysteine, and vitamin C). The role of rotenone-induced mitochondrial ROS in apoptosis was also confirmed by the finding that HT1080 cells overexpressing magnesium superoxide dismutase were more resistant to rotenone-induced apoptosis than control cells. These results suggest that rotenone is able to induce apoptosis via enhancing the amount of mitochondrial reactive oxygen species production.
Published:
2003
Title:
Molecular epidemiology of sporadic breast cancer: The role of polymorphic genes involved in oestrogen biosynthesis and metabolism
Authors:
Mitrunen, K.; Hirvonen, A.
Abstract:
The major known risk factors for female breast cancer are associated with prolonged exposure to increased levels of oestrogen. The predominant theory relates to effects of oestrogen on cell growth. Enhanced cell proliferation, induced either by endogenous or exogenous oestrogens, increases the number of cell divisions and thereby the possibility for mutation. However, current evidence also supports a role for oxidative metabolites, in particular catechol oestrogens, in the initiation of breast cancer. As observed in drug and chemical metabolism, there is considerable interindividual variability (polymorphism) in the conjugation pathways of both oestrogen and catechol oestrogens. These person-to-person differences, which are attributed to polymorphisms in the genes encoding for the respective enzymes, might define subpopulations of women with higher lifetime exposure to hormone-dependent growth promotion, or to cellular damage from particular oestrogens and/or oestrogen metabolites. Such variation could explain a portion of the cancer susceptibility associated with reproductive effects and hormone exposure. In this paper the potential role of polymorphic genes encoding for enzymes involved in oestrogen biosynthesis (CYP17, CYP19, and 17β-HSD) and conversion of the oestrogen metabolites and their by-products (COMT, CYP1A1, CYP1B1, GSTM1, GSTM3, GSTP1, GSTT1 and MnSOD) in modulating individual susceptibility to breast cancer are reviewed. Although some of these low-penetrance genes appeared as good candidates for risk factors in the etiology of sporadic breast cancer, better designed and considerably larger studies than the majority of the studies conducted so far are evidently needed before any firm conclusions can be drawn. © 2003 Elsevier Science B.V. All rights reserved.
Published:
2003
Title:
Natural history of Homo erectus
Authors:
Antón, S. C
Abstract:
Published:
2003
Title:
Nutrition ecology: the contribution of vegetarian diets
Authors:
Leitzmann, Claus
Abstract:
Nutrition ecology is an interdisciplinary scientific discipline that encompasses the entire nutrition system, with special consideration of the effects of nutrition on health, the environment, society, and the economy. Nutrition ecology involves all components of the food chain, including production, harvesting, preservation, storage, transport, processing, packaging, trade, distribution, preparation, composition, and consumption of food, as well as disposal of waste materials. Nutrition ecology has numerous origins, some of which go back to antiquity. The introduction of industrialized agriculture and mass animal production gave rise to various negative influences on the environment and health. Food quality is determined in part by the quality of the environment. The environment, in turn, is influenced by food consumption habits. Research shows that vegetarian diets are well suited to protect the environment, to reduce pollution, and to minimize global climate changes. To maximize the ecologic and health benefits of vegetarian diets, food should be regionally produced, seasonally consumed, and organically grown. Vegetarian diets built on these conditions are scientifically based, socially acceptable, economically feasible, culturally desired, sufficiently practicable, and quite sustainable.
Published:
2003
Title:
Obesity, diabetes, hypertension, and vegetarian status among Seventh-Day Adventists in Barbados: preliminary results
Authors:
Brathwaite, Noel; Fraser, Henry S.; Modeste, Naomi; Broome, Hedy; King, Rosaline
Abstract:
A population-based sample of Seventh-Day Adventists was studied to determine the relationship between vegetarian status, body mass index (BMI), obesity, diabetes mellitus (DM), and hypertension, in order to gain a better understanding of factors influencing chronic diseases in Barbados. A systematic sampling from a random start technique was used to select participants for the study. A standard questionnaire was used to collect data on demographic and lifestyle characteristics, to record anthropometrics and blood pressure measurements, and to ascertain the hypertension and diabetes status of participants. The sample population consisted of 407 Barbadian Seventh-Day Adventists (SDAs), who ranged in age from 25 to 74 years. One hundred fifty-three (37.6%) participants were male, and 254 (62.4%) were female, and 43.5% were vegetarians. The prevalence rates of diabetes and hypertension were lower among long-term vegetarians, compared to non-vegetarians, and long-term vegetarians were, on average, leaner than non-vegetarians within the same cohort. A significant association was observed between a vegetarian diet and obesity (vegetarian by definition P=.04, self-reported vegetarian P=.009) in this population. Other components of the study population lifestyle should be further analyzed to determine the roles they may plan in lessening the prevalence rates of obesity, diabetes, and hypertension.
Published:
2003
Title:
Old boundaries and new horizons: the Weipa shell mounds reconsidered
Authors:
Morrison, M. J.
Abstract:
Published:
2003
Title:
Overweight, Obesity, and Mortality from Cancer in a Prospectively Studied Cohort of U.S. Adults
Authors:
Calle, Eugenia E
Abstract:
Published:
2003
Title:
Paradox of Plenty: A Social History of Eating in Modern America
Authors:
Levenstein, Harvey
Abstract:
Published:
2003
Title:
Patterns of performance degradation and restoration during sleep restriction and subsequent recovery: A sleep dose-response study
Authors:
Belenky, Gregory; Wesensten, Nancy J.; Thorne, David R.; Thomas, Maria L.; Sing, Helen C.; Redmond, Daniel P.; Russo, Michael B.; Balkin, Thomas J.
Abstract:
Daytime performance changes were examined during chronic sleep restriction or augmentation and following subsequent recovery sleep. Sixty-six normal volunteers spent either 3 (n = 18), 5 (n= 16), 7 (n = 16), or 9 h (n = 16) daily time in bed (TIB) for 7 days (restriction/augmentation) followed by 3 days with 8 h daily TIB (recovery). In the 3-h group, speed (mean and fastest 10% of responses) on the psychomotor vigilance task (PVT) declined, and PVT lapses (reaction times greater than 500 ms) increased steadily across the 7 days of sleep restriction. In the 7- and 5-h groups speed initially declined, then appeared to stabilize at a reduced level; lapses were increased only in the 5-h group. In the 9-h group, speed and lapses remained at baseline levels. During recovery, PVT speed in the 7- and 5-h groups (and lapses in the 5-h group) remained at the stable, but reduced levels seen during the last days of the experimental phase, with no evidence of recovery. Speed and lapses in the 3-h group recovered rapidly following the first night of recovery sleep; however, recovery was incomplete with speed and lapses stabilizing at a level comparable with the 7- and 5-h groups. Performance in the 9-h group remained at baseline levels during the recovery phase. These results suggest that the brain adapts to chronic sleep restriction. In mild to moderate sleep restriction this adaptation is sufficient to stabilize performance, although at a reduced level. These adaptive changes are hypothesized to restrict brain operational capacity and to persist for several days after normal sleep duration is restored, delaying recovery.
Published:
2003
Title:
Perspectives on the metabolic management of epilepsy through dietary reduction of glucose and elevation of ketone bodies
Authors:
Greene, Amanda E.; Todorova, Mariana T.; Seyfried, Thomas N.
Abstract:
Brain cells are metabolically flexible because they can derive energy from both glucose and ketone bodies (acetoacetate and β-hydroxybutyrate). Metabolic control theory applies principles of bioenergetics and genome flexibility to the management of complex phenotypic traits. Epilepsy is a complex brain disorder involving excessive, synchronous, abnormal electrical firing patterns of neurons. We propose that many epilepsies with varied etiologies may ultimately involve disruptions of brain energy homeostasis and are potentially manageable through principles of metabolic control theory. This control involves moderate shifts in the availability of brain energy metabolites (glucose and ketone bodies) that alter energy metabolism through glycolysis and the tricarboxylic acid cycle, respectively. These shifts produce adjustments in gene-linked metabolic networks that manage or control the seizure disorder despite the continued presence of the inherited or acquired factors responsible for the epilepsy. This hypothesis is supported by information on the management of seizures with diets including fasting, the ketogenic diet and caloric restriction. A better understanding of the compensatory genetic and neurochemical networks of brain energy metabolism may produce novel antiepileptic therapies that are more effective and biologically friendly than those currently available.
Published:
2003
Title:
Polymorphisms past and present
Authors:
Eckhardt, R. B
Abstract:
Published:
2003
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