bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of early biomarkers of muscle anabolic response to testosterone
Authors: Chen Fabian , Lam Raymond , Shaywitz David , Hendrickson Ronald C. , Opiteck Gregory J. , Wishengrad Dana , Liaw Andy , Song Qinghua , Stewart Adrian J. , Cummings Corinne E. , Beals Chan , Yarasheski Kevin E. , Reicin Alise , Ruddy Marcella , Hu Xuguang , Yates Nathan A. , Menetski Joseph , Herman Gary A.
Published: February 2011

Background

Early biomarkers of skeletal muscle anabolism will facilitate the development of therapies for sarcopenia and frailty.

Methods and results

We examined plasma type III collagen N‐terminal propeptide (P3NP), skeletal muscle protein fractional synthesis rate, and gene and protein expression profiles to identify testosterone‐induced changes in muscle anabolism. Two placebo‐controlled studies enrolled community‐dwelling men (study 1, 60–75 years; study 2, 18–40 years) with low to normal testosterone levels. Men were randomized to lower dose (study 1, 100 mg; study 2, 200 mg) or higher dose (study 1, 300 mg; study 2, 600 mg) single intramuscular testosterone or saline injection. After 1 week, testosterone acutely increased plasma P3NP levels in a dose‐dependent manner and altered the expression of several skeletal muscle transcripts and proteins. Though not statistically significant, mixed muscle protein fractional synthesis rate tended to increase (1.08‐fold with 100 mg testosterone, 1.12‐fold with 300 mg testosterone). Testosterone exposure also increased skeletal muscle expression of the collagen type III gene that encodes P3NP.

Conclusion

P3NP is a potentially useful early biomarker for muscle anabolic therapy. Skeletal muscle protein and RNA profiling are useful tools for the discovery of novel muscle anabolic biomarkers.
Inflammatory Polyps of the Nasal turbinates of cats: An argument for designation as feline mesenchymal nasal hamartoma
Authors: Greci Valentina , Mortellaro Carlo M. , Olivero Daniela , Cocci Andrea , Hawkins Eleanor C.
Published: February 2011

Inflammatory polyps of the nasal turbinates (IPNT) in cats are benign growths that are histologically distinct from feline nasopharyngeal polyps. Most cats with IPNT are presented at less than 1 year of age with sneezing, noisy breathing and epistaxis, but without mucoid or mucopurulent nasal discharge. Histologically, IPNT are characterised by the presence of woven bone as part of the proliferating stroma and erythrocyte-filled spaces. These unique histological features are analogous to nasal hamartomas (NH) of children, specifically chondromesenchymal hamartoma (NCMH) and sinonasal fibro-osseous hamartoma (SFOH), which also result in signs of nasal obstruction, sneezing and epistaxis. In our study, clinical and histopathological features in five cats with IPNT were compared with published descriptions of NH in children. We conclude that the terminology ‘feline mesenchymal nasal hamartoma’ provides a more accurate description of the disease currently termed IPNT, and has the added advantage of being consistent with its human counterpart.
Admissible solutions for Dirac equations with singular and non-monotone nonlinearity
Authors: Dong Yujun , Xie Jing
Published: February 2011

By making use of Merle's general shooting method we investigate Dirac equations of the form

Here it is possible that F(0) = −∞ and that F(s) defined on (0,+∞) is not monotonously nondecreasing. Our results cover some known ones as a special case.
The impact of geochemistry on convective mixing in a gravitationally unstable diffusive boundary layer in porous media: CO2 storage in saline aquifers
Authors: GHESMAT KARIM , HASSANZADEH HASSAN , ABEDI JALAL
Published: February 2011

The storage of carbon dioxide and acid gases in deep geological formations is considered a promising option for mitigation of greenhouse gas emissions. An understanding of the primary mechanisms such as convective mixing and geochemistry that affect the long-term geostorage process in deep saline aquifers is of prime importance. First, a linear stability analysis of an unstable diffusive boundary layer in porous media is presented, where the instability occurs due to a density difference between the carbon dioxide saturated brine and the resident brine. The impact of geochemical reactions on the stability of the boundary layer is examined. The equations are linearised, and the obtained system of eigenvalue problems is solved numerically. The linear stability results have revealed that geochemistry stabilises the boundary layer as reaction consumes the dissolved carbon dioxide and makes the density profile, as the source of instability, more uniform. A detailed physical discussion is also presented with an examination of vorticity and concentration eigenfunctions and streamlines' contours to reveal how the geochemical reaction may affect the hydrodynamics of the process. We also investigate the effects of the Rayleigh number and the diffusion time on the stability of a boundary layer coupled with geochemical reactions. Nonlinear direct numerical simulations are also presented, in which the evolution of density-driven instabilities for different reaction rates is discussed. The development of instability is precisely studied for various scenarios. The results indicate that the boundary layer will be more stable for systems with a higher rate of reaction. However, our quantitative analyses show that more carbon dioxide may be removed from the supercritical free phase as the measured flux at the boundary is always higher for flow systems coupled with stronger geochemical reactions.
Antioxidant effect of pomegranate extract in reducing acute inflammation due to myringotomy
Authors: Kahya V , Meric A , Yazici M , Yuksel M , Midi A , Gedikli O
Published: February 2011

Objective:

To assess the effect of pomegranate extract on acute inflammation due to myringotomy.

Design:

Prospective, randomised study.

Subjects:

Thirty Sprague–Dawley rats were divided into three groups. Group one constituted controls. Group two underwent myringotomy. Group three underwent myringotomy and also received 100 µl/day pomegranate extract, via gavage, one day before and two days after surgery. Following sacrifice 48 hours after myringotomy, the animals' right ears were used to determine the concentration of reactive oxygen species, using the chemiluminescence method; left ears were used for histological study.

Results:

Reactive oxygen species levels were significantly decreased in group three compared with group two (p < 0.01). The density of inflammatory cells in group three was significantly less than that in group two (p < 0.01). Lamina propria thickness and vessel density were also significantly decreased in group three compared with group two (p < 0.01).

Conclusion:

Our results indicate that oral pomegranate extract decreases reactive oxygen species concentration and acute inflammation in the tympanic membrane after myringotomy.
Failure to thrive in a population context: two contrasting studies of feeding and nutritional status
Authors: Wright Charlotte , Loughridge Jane , Moore Gill
Published: February 2011

Although failure to thrive (FTT) is generally thought to be a nutritional problem, dietary intake in children with FTT has been little researched. We describe two community-based studies of dietary intake and eating behaviour in FTT. The first study of ninety-seven children with FTT identified by population screening found that only a minority of case children were associated with neglect, organic illness or deprivation, even though dietary information suggested an underlying nutritional cause in the majority. Limited case-control data suggested significantly delayed weaning and less liking for food in general among the case children. The second study found diminished appetite, delayed progression onto solid foods and fewer foods eaten by forty-four children referred with FTT compared with forty-five controls, but was unable to detect a significant difference in energy intake, even allowing for varying body composition and other confounding variables. This study also revealed the bias introduced by recruiting case children by referral rather than screening, and that despite rigorous matching procedures the controls were not representative of the general population. These studies suggest a wide range of differences in eating behaviour and feeding patterns between children with FTT and controls, but suggest that measurements of nutrient totals may not be robust. Studies of FTT based on referred children can be misleading, as can comparison with controls, unless allowance can be made for important confounding social variables.
Malnutrition, morbidity and mortality in children and their mothers
Authors: Tomkins Andrew
Published: February 2011

While being underweight or stunted is recognized as an important risk factor for increased prevalence and severity of infection and high mortality rates, there is increasing evidence for an independent role for micronutrient deficiency. Improving vitamin A status reduces mortality among older infants and young children and reduces pregnancy-related mortality; it also reduces the prevalence of severe illness and clinic attendance among children. Improving Zn status reduces morbidity from diarrhoeal and respiratory infection. Treatment of established infection with vitamin A is effective in measles-associated complications, but is not as useful in the majority of diarrhoeal or respiratory syndromes. Zn supplements, however, have significant benefit on the clinical outcome of diarrhoeal and respiratory infections. Concerns that Fe supplements might increase morbidity if given in malarious populations appear to be decreasing, in the light of new studies on Fe supplements showing improved haemoglobin without an increase in morbidity. Breast-feeding, well known to protect against diarrhoea, is also important in protecting against respiratory infection, especially in the young infant. Transmission of human immunodeficiency virus (HIV) in breast milk is recognized, but new data showing reduced transmission in infants who receive exclusive breast-feeding rather than mixed feeding reinforces the importance of promoting this practice in areas where environmental contamination precludes the safe use of other infant feeding regimens. The presence of subclinical mastitis, now recognized to occur in approximately 20 % of mothers in several developing countries, has been shown to increase the concentration of HIV in breast milk. Preliminary findings suggest that the prevalence of subclinical mastitis is reduced by dietary supplements containing antioxidants. Governments and international agencies now have a strong scientific basis to be much more active and innovative in the introduction of focused nutrition interventions especially micronutrients, for the control of infection.
Early nutrition and the development of immune function in the neonate
Authors: Kelly D. , Coutts A. G. P.
Published: February 2011

The present review will concentrate on the development of the gut-associated lymphoid tissue and the role of early nutrition in promoting immune function. The intestine is the largest immune organ in the body, and as such is the location for the majority of lymphocytes and other immune effector cells. The intestine is exposed to vast quantities of dietary and microbial antigens, and is the most common portal of entry for pathogens, some of which are potentially lethal. The development of normal immune function of the intestine is therefore vital for survival, and is dependent on appropriate antigen exposure and processing, and also an intact intestinal barrier. In early life innate mechanisms of defence are probably more important than active or adaptive mechanisms in responding to an infectious challenge, since the healthy neonate is immunologically naïve (has not seen antigen) and has not acquired immunological memory. During this period maternal colostrum and milk can significantly augment resistance to enteric infections. The mechanisms of enhancing disease resistance are thought to be passive, involving a direct supply of anti-microbial factors, and active, by promoting the development of specific immune function. A tolerance response to dietary and non-invasive antigens is generally induced in the gut. However, it must also be able to mount an adequate immune response to ensure clearance of foreign antigens. It is now recognized that regulation of tolerance and active immune responses is critical to health, and failure to regulate these responses can lead to recurrent infections, inflammatory diseases and allergies. The education of the immune system in early life is thought to be critical in minimizing the occurrence of these immune-based disorders. During this phase of development maternal milk provides signals to the immune system that generate appropriate response and memory. One factor that has been proposed to contribute to the increase in the incidence of immune-based disorders, e.g. atopic diseases in Western countries, is thought to be the increased prevalence of formula-feeding.
New perspectives on the use of tropical plants to improve ruminant nutrition
Authors: Teferedegne B.
Published: February 2011

Inadequate nutrition is the main cause of low productivity by ruminants in sub-Saharan Africa. The primary feed resources in the region include natural pasture and crop residues that have tough texture, poor digestibility and are deficient in nutrients. These deficiencies can be corrected by supplementation with high-density feeds such as oilseed cakes and proteins of animal origin. However, protein sources such as oilseed cakes are beyond the economic reach of most farmers, while the incidence of bovine spongiform encephalopathy in Western intensive animal production may be thought to argue against the use of animal proteins. Local tree legumes have been investigated as potential supplements for ruminants because of their beneficial effect of increasing metabolizable energy intake, N intake and feed efficiency, and improving animal performance. However, our work has suggested that some plant materials may have a nutritional value beyond simply their nutrient content, i.e. as rumen-manipulating agents. The foliage of some tree legumes has been shown to be selectively toxic to rumen protozoa. Rumen protozoa ingest and digest bacteria and fungi, degrading their cellular protein to NH3. Microbial protein turnover due to protozoal predation in the rumen may result in the net microbial protein outflow being less than half the total protein synthesized. Results fromin vivoexperiments have clearly shown that duodenal flow of both undegraded dietary and bacterial protein is generally increased by defaunation. However, no practical method has been developed to date to eliminate protozoa. Anti-protozoal plants may be promising, safe, natural defaunating agents.
Nutritional aspects and possible pathological mechanisms of hyperhomocysteinaemia: an independent risk factor for vascular disease
Authors: McKinley Michelle C.
Published: February 2011

Numerous case–control and prospective studies have identified elevated plasma homocysteine as a strong independent risk factor for cerebovascular, cardiovascular and peripheral vascular disease. Homocysteine is formed as a result of the breakdown of the dietary amino acid methionine. Once formed, homocysteine is either remethylated to methionine, or undergoes a trans-sulfuration reaction to form cysteine. The re-methylation of homocysteine to methionine is dependent on three B-vitamins, i.e. riboflavin, vitamin B12and folate. The second pathway of homocysteine metabolism is the trans-sulfuration pathway which requires both vitamin B6and riboflavin for its activity. Thus, up to four B-vitamins are required for intracellular homocysteine metabolism. Many studies have noted strong inverse relationships between homocysteine levels and the status of both vitamin B12and folate. However, the relationship between vitamin B6status and homocysteine is still uncertain. Similarly, numerous intervention studies have demonstrated effective lowering of homocysteine levels as a result of folate and vitamin B12supplementation, while the homocysteine-lowering ability of vitamin B6is unclear. Even though riboflavin plays a crucial role in both the trans-sulfuration and remethylation pathways of homocysteine metabolism, the relationship between riboflavin status and homocysteine levels has not been investigated. The exact mechanism that explains the vascular toxicity of elevated homocysteine levels is unknown at present, studies indicate that it is both atherogenic and thrombogenic. To date, no randomized clinical trial has demonstrated that lowering of homocysteine levels is beneficial in terms of reducing the prevalence of vascular disease. It is probable, however, that optimal B-vitamin status is important in the prevention of vascular disease.
Plenary Lecture
Authors: Drewnowski Adam
Published: February 2011

Taste preferences, food choices and eating habits all change with age. The transition from childhood to adolescence and adult life is associated with reduced sweet taste preferences, lower sugars consumption and reduced energy density of the diet. Ageing is associated with elevated acceptance of bitter tastes, elevated preferences for vegetables and salad greens, and increased consumption of whole grains, vegetables and fruit. The age-associated drop in energy intakes is achieved through a reduction in the weight and volume of food consumed, as well as a reduction in the overall energy density of the diet. Energy density drops from a peak of 5 kJ (1.2 kcal)/g in adolescence and early adult life to a low of 3.1 kJ (0.75 kcal)/g for adult women aged 45–54 years. Older adults, particularly women, consume less fat and saturated fat and more fibre and vitamin C, suggesting a shift in consumption from snacks, sweets and desserts towards grains, vegetables and fruit. These changes in food preferences and eating habits are associated, on a population level, with a decline in preferences for sweet taste and with increased acceptance of bitter tastes. At present there are no data to show a causal relationship between age-related changes in sensory function and the selection of a more bulky energy-dilute diet. However, it is a plausible hypothesis that sensory factors mediate adjustments in energy density of foods at different life stages.
The growing years and prevention of osteoporosis in later life
Authors: Weaver Connie M.
Published: February 2011

Ca is the major mineral in bone, and 99 % of the Ca in the body resides in the skeleton. Skeletal mass is a determinant of risk of fracture in childhood as well as adulthood. Over 40 % of adult peak bone mass is acquired during adolescence. This period is when lifestyle choices, including ensuring adequate dietary Ca, regular weight-bearing exercise and avoiding hormonal insufficiency, are especially important. Current Ca intakes for adolescent females are woefully inadequate.
Part 2 Micronutrients in the severely-injured patient
Authors: Shenkin Alan
Published: February 2011

The trace element and vitamin requirements of severely-ill injured patients depend on a complex interaction of the status of the patient at the time of admission, ongoing losses and the potential benefit of supplying large amounts of individual micronutrients. Characteristic clinical deficiency states are now uncommon, but subclinical deficiency is of growing concern. The main effects of subclinical deficiency are: (1) an altered balance of reactive oxygen species and antioxidants, leading to oxidative damage of polyunsaturated fatty acids and nucleic acids, and possibly to increased activation of the transcription factor nuclear factor-κB, with increased production of pro-inflammatory cytokines; (2) impaired immune function with increased likelihood of infectious complications. Laboratory tests to optimize intake in such critically-ill patients lack sensitivity and specificity, this situation being made worse as a result of the acute-phase response. Recent studies have indicated the clinical benefit of providing large amounts of certain micronutrients in burned and head-injured patients. Further clinical studies are now required to define optimal levels of provision in different disease states, with a particular emphasis on markers of tissue function and clinical outcome.
Role of substrate utilization and thermogenesis on body-weight control with particular reference to alcohol
Authors: Schutz Yves
Published: February 2011

Alcohol (ethanol; EtOH) provides fuel energy to the body (29·7 kJ (7·1 kcal)/g, 23·4 kJ (5·6 kcal)/ml), as do other macronutrients, but no associated essential nutrients. The thermogenic effect of EtOH (on average 15 % of its metabolizable value) is much greater than that of the main substrates utilized by the body, i.e. fat and carbohydrates (CHO), suggesting a lower net efficiency of energy utilization for EtOH than for fat and CHO. EtOH cannot be stored in the body and is toxic, so that there is an obligatory continuous oxidation of EtOH and it becomes the priority fuel to be metabolized. In contrast to CHO, its rate of oxidation does not depend on the dose ingested. As with CHO intake, it engenders a shift in postprandial substrate utilization (decrease in fat oxidation), but by a non-insulin-mediated mechanism. A limited amount of EtOH can be converted to fatty acids by hepatic de novo lipogenesis (as occurs with high levels of CHO feeding) from acetate production, which inhibits lipolysis in peripheral tissues. There is no evidence that EtOH consumed under normoenergetic conditions (i.e. isoenergetically replacing CHO or fat) leads to greater body fat storage than fat or CHO. However, there is still a lack of experimental studies on the influence of EtOH on the level of spontaneous physical activity in man. This effect may well depend on the dose of EtOH consumed as well as other intrinsic factors.
Vitamin D: a natural inhibitor of multiple sclerosis
Authors: Hayes Colleen E.
Published: February 2011

Inheriting genetic risk factors for multiple sclerosis (MS) is not sufficient to cause this demyelinating disease of the central nervous system; exposure to environmental risk factors is also required. MS may be preventable if these unidentified environmental factors can be avoided. MS prevalence increases with decreasing solar radiation, suggesting that sunlight may be protective in MS. Since the vitamin D endocrine system is exquisitely responsive to sunlight, and MS prevalence is highest where environmental supplies of vitamin D are lowest, we have proposed that the hormone, 1,25-dihydroxycholecalciferol (1,25-(OH)2D3), may protect genetically-susceptible individuals from developing MS. Evidence consistent with this hypothesis comes not only from geographic studies, but also genetic and biological studies. Over-representation of the vitamin D receptor geneballele was found in Japanese MS patients, suggesting it may confer MS susceptibility. Fish oil is an excellent vitamin D source, and diets rich in fish may lower MS prevalence or severity. Vitamin D deficiency afflicts most MS patients, as demonstrated by their low bone mass and high fracture rates. However, the clearest evidence that vitamin D may be a natural inhibitor of MS comes from experiments with experimental autoimmune encephalomyelitis (EAE), a model of MS. Treatment of mice with 1,25-(OH)2D3completely inhibited EAE induction and progression. The hormone stimulated the synthesis of two anti-encephalitogenic cytokines, interleukin 4 and transforming growth factor β-1, and influenced inflammatory cell trafficking or apoptosis. If vitamin D is a natural inhibitor of MS, providing supplemental vitamin D to individuals who are at risk for MS would be advisable.
Micronutrients and host resistance to viral infection
Authors: Beck Melinda A. , Matthews Colette C.
Published: February 2011

Previous work in our laboratory demonstrated that a virus could undergo rapid mutation in a host deficient in Se, leading to a normally avirulent virus acquiring virulence due to genome changes. Once these mutations occur, even a host with adequate Se-nutriture is susceptible to the newly virulent virus. What influence does the deficiency in Se have on the immune response of the host? Infection with myocarditic strains of coxsackievirus induces an inflammatory response in the cardiac tissue. It is this immune response that induces the heart damage, rather than direct viral effects on the heart tissue. Chemokines are chemo-attractant molecules that are secreted during an infection in order to attract immune cells to the site of the injury, and have been found to be important for the development of coxsackievirus-induced myocarditis. We found that a deficiency in Se influences the expression of mRNA for the chemokine monocyte chemo-attractant protein-1, which may have implications for the development of myocarditis in the Se-deficient host. Expression of mRNA for interferon-γ was also greatly decreased in the Se-deficient animal. Thus, a deficiency in Se can have profound effects on the host as well as on the virus itself. How the alteration of the immune response of the Se-deficient animal affects the development of the virulent genotype remains to be answered.
The nutritional value of plant-based diets in relation to human amino acid and protein requirements
Authors: Millward D. Joe
Published: February 2011

The adequacy of plant-based diets in developed and developing countries as sources of protein and amino acids for human subjects of all ages is examined. Protein quantity is shown not to be an issue. Digestibility is identified as a problem for some cereals (millet (Panicum miliaceum) and sorghum (Sorghumsp.)) and generally is poorly understood. Direct measurements of biological value in children are reviewed and scoring is consid-ered. Various existing requirement values for amino acids and especially lysine are reviewed, and it is concluded that stable-isotope studies do not yet provide adequate alternative values to N balance data, which for lysine are robust after recalculation and adjustment. A new maintenance requirement pattern is developed, with higher values than those of Food and Agriculture Organization/World Health Organization/United Nations University (1985) but lower values than the Massachusetts Institute of Technol-ogy pattern (Younget al.1989). Calculations of age-related amino acid requirements are based on most recent estimates of human growth and maintenance protein requirements, a tissue amino acid pattern and the new maintenance amino acid pattern. These values appear valid when used to score plant proteins, since they indicate values similar to or less than the biological value measured directly in young children. When used to score plant-based diets in India, no marked deficiencies are identified. All regions score > 1 for adults, whilst for children scores range from > 1, (Tamil Nadhu) from 6 months of age to 0.78 (West Bengal), rising to 0.9 in the 2–5 year old, consistent with reports that high-lysine maize supports similar weight and height growth to that of casein. Inadequate amino acid supply is not an issue with most cereal-based diets.
Health benefits of a vegetarian diet
Authors: Key Timothy J. , Davey Gwyneth K. , Appleby Paul N.
Published: February 2011

Compared with non-vegetarians, Western vegetarians have a lower mean BMI (by about 1 kg/m2), a lower mean plasma total cholesterol concentration (by about 0.5 mmol/l), and a lower mortality from IHD (by about 25 %). They may also have a lower risk for some other diseases such as constipation, diverticular disease, gallstones and appendicitis. No differences in mortality from common cancers have been established. There is no evidence of adverse effects on mortality. Much more information is needed, particularly on other causes of death, other morbidity including osteoporosis, and long-term health in vegans. The evidence available suggests that widespread adoption of a vegetarian diet could prevent approximately 40 000 deaths from IHD in Britain each year.
Childhood leukaemia: a model of pre-obesity
Authors: Ventham J. C. , Reilly J. J.
Published: February 2011

The prevalence of obesity in children, as in adults, is increasing dramatically. The extent to which this is due to reduced energy expenditure, increased energy intake, or both, is unclear at present. This in part reflects the limitations of existing models of the pre-obese state. In childhood acute lymphoblastic leukaemia (ALL), patients typically gain weight excessively during and after 2 years of therapy, and are at high risk of becoming obese. Previous studies have failed to identify the cause of obesity in these patients. We have tested the hypothesis that excess weight gain in ALL is due to reduced total energy expenditure (TEE), measured using the doubly-labelled water method, and have identified risk factors for excess weight gain in ALL. Pre-obese children with ALL in the dynamic phase of weight gain are less physically active than their peers, with a reduced TEE of approximately 1.2 (95 % CI 0.2, 2.2) MJ/d. While other factors might contribute to excess weight gain, lifestyle (i.e. reduced habitual physical activity) plays a central role in ALL. Several considerations suggest that ALL might be a useful model of the pre-obese state: lifestyle is critical to development of obesity in ALL; ALL is relatively common; approximately 70 % of patients survive; patients are readily accessible during the 2 years of therapy and beyond.
Optimal macronutrient balance
Authors: Gibney Michael J.
Published: February 2011

There is at present a justifiable debate as to the optimum level of total dietary fat which will reduce the risk of obesity without an elevation of plasma triacylglycerol or a depression of plasma HDL-cholesterol. Total plasma cholesterol and LDL-cholesterol levels are lowered and risk of fatal myocardial infarction is lowered when either saturated or trans-unsaturated fatty acids are replaced isoenergetically by either monounsaturated or polyunsaturated fatty acids. The triacylglycerol-raising and HDL-lowering effects of low-fat high-carbohydrate diets can be over-come with low intakes of n−3 polyunsaturated fatty acids and moderate exercise. Whilst a reduction in dietary fat is being attained in many countries, the reduction is uniform across all fatty acids, leaving dietary fat composition unchanged. The ability of low-fat diets to reduce cholesterol and cause a fall in body weight is not influenced by the carbohydrate ratio starch: sugars in the diet. However, weight-gain susceptibility to high intakes of dietary fat and the plasma cholesterol responsiveness to diet are considerably influenced by common genetic polymorphisms.
Optimal nutrition: vitamin A and the carotenoids
Authors: Thurnham David I. , Northrop-Clewes Christine A.
Published: February 2011

There are two major dietary sources of vitamin A: easily absorbed retinyl palmitate in foods of animal origin, and poorly bioavailable carotenoids from plant foods. Plasma retinol is tightly controlled, probably by regulation of retinol-binding protein (RBP) formation in the liver, and only hormonal factors (e.g. oral contraceptives) and infection will alter the homeostasis. Delivery of retinol to the tissues is facilitated by the RBP-retinol complex; however, there is evidence that this mechanism can be bypassed when very high doses of vitamin A are given. Some retinyl ester may be released to tissues from chylomicrons when the latter bind to tissue lipoprotein receptors during their passage from the gut to the liver following a meal. High-dose vitamin A therapy is a means of rapidly improving vitamin A status in persons with sub-optimal vitamin A nutrition but there are dangers of toxic symptoms (e.g. teratogenicity) from excess vitamin A usage. Evidence is presented to suggest that the plasma retinol : RBP may be a guide to optimal vitamin A status, since values less than one frequently occur in less-developed countries and during infection. In contrast to plasma retinol, plasma carotenoids reflect the dietary intake of plant foods. However, absorption is limited by poor bioavailability and a saturable uptake mechanism in competition with other phytochemicals. Recent work on bioavailability suggests that the calculation of plant food vitamin A activity should be re-examined. Illness has little influence on plasma levels except by suppressing appetite. Carotenoids are generally regarded as non-toxic yet intervention studies with β-carotene in smokers have been associated with increased lung cancer and heart disease. Some carotenoids are important as vitamin A precursors, but the physiological importance of their antioxidant properties is not known and consequently the amount needed for optimal nutrition is uncertain.
Optimal nutrition: vitamin E
Authors: Morrissey P. A. , Sheehy P. J. A.
Published: February 2011

Interest in the role of vitamin E in disease prevention has encouraged the search for reliable indices of vitamin E status. Most studies in human subjects make use of static markers, usually a-tocopherol concentrations in plasma or serum. Plasma or serum α-tocopherol concentrations of < 11.6, 11.6–16.2, and > 16.2 mmol/l are normally regarded as indicating deficient, low and acceptable vitamin E status respectively, although more recently it has been suggested that the optimal plasma α-tocopherol concentration for protection against cardiovascular disease and cancer is > 30 μmol/l at common plasma lipid concentrations in combination with plasma vitamin C concentrations of > 50 μmol/l and > 0.4 mmol β-carotene/l. Assessment of vitamin E status has also been based on α-tocopherol concentrations in erythrocytes, lymphocytes, platelets, lipoproteins, adipose tissue, buccal mucosal cells and LDL, and on α- tocopherol: γ-tocopherol in serum or plasma. Erythrocyte susceptibility to haemolysis or lipid oxidation, breath hydrocarbon exhalation, oxidative resistance of LDL, and α-tocopheryl quinone concentrations in cerebrospinal fluid have been used as functional markers of vitamin E status. However, many of these tests tend to be non-specific and poorly standardized. The recognition that vitamin E has important roles in platelet, vascular and immune function in addition to its antioxidant properties may lead to the identification of more specific biomarkers of vitamin E status.
Vitamin C: prospective functional markers for defining optimal nutritional status
Authors: Benzie Iris F. F.
Published: February 2011

Most species of plants and animals synthesize ascorbic acid, but human subjects cannot, making vitamin C an essential component of our diet. Relationships between vitamin C intake and status, and between status and health are not yet clear. There is evidence, however, that higher intake of vitamin C is associated with lower risk of disease, supporting the concept that optimal intake is needed for optimal vitamin C status, and that both factors are required for optimal health. Vitamin C has low toxicity in healthy subjects, but a clear definition of optimal status and the dietary intake required to meet and maintain this status is needed before a change in the current recommended intake can be considered. Available evidence suggests that intake of 200 mg vitamin C/d saturates tissues and maintains fasting plasma levels above the proposed threshold (50 μmol/l) for minimum risk of CHD. However, the issue of whether or not these levels produce ‘optimal vitamin C status’ awaits the clear and accepted definition of the term. This definition in turn awaits the development of reliable functional markers capable of assessing the effects of varying levels of vitamin C nutriture. In the present paper the relationship between intake and body stores of vitamin C and the role of vitamin C in human health are reviewed briefly. The requirements of a reliable functional marker of human vitamin C status are defined, three classes of functional markers (molecular, biochemical and physiological) are described, and possible candidate markers are examined.
Considerations for determining ‘optimal nutrition’ for copper, zinc, manganese and molybdenum
Authors: Failla Mark L.
Published: February 2011

Defining optimal dietary intakes of Cu and Zn throughout the life cycle continues to present a considerable challenge for nutrition scientists. Although the daily intake of these micronutrients is below that currently recommended for many groups, traditional biochemical indicators of nutritional status for these trace metals largely remain within the normal range. Thus, it is unclear whether the recommended daily intakes may be unnecessarily high, or if the commonly-used markers simply lack the necessary sensitivity and specificity that are required for accurately assessing Cu and Zn status. The increasing number of reports that daily supplements with these trace metals enhance the activities of selective metalloenzymes and specific cellular and organ processes further points out the need to differentiate between meeting the requirement and providing optimal nutriture. Results from recent studies suggesting that alternative molecular and functional markers possess sufficient sensitivity to better assess Cu and Zn status are discussed. Likewise, recent studies evaluating the impact of very low and excessive levels of dietary Mn and Mo on selective biochemical and metabolic indicators are reviewed.
The effects of specific nutrients on the regulation of feeding behaviour in human subjects
Authors: French Stephen J.
Published: February 2011

Regulation of short-term energy intake involves the balance of positive drives to eat arising from the sight, smell and palatability of food with negative feedback signals from learned associations, gastrointestinal and metabolic signals. The stomach and small intestine are major sites in the feedback inhibition of food intake and subsequent period of appetite suppression. The present paper reviews the evidence that not only does the nature of the regulatory signal suppressing food intake depend on the type and energy content of nutrient consumed, but also the specific chemical composition of the nutrients and the site at which they are delivered. It is evident that feedback inhibition of feeding can be modulated by the particular chemical structure of nutrients (e.g. specific sugar or triacylglycerol structures). These differences in response are likely to be a consequence of differences in physical properties of particular nutrients depending on their chemical structure, and may also result from different receptor affinities for specific dietary structures. Moreover, the site of administration of nutrients can also profoundly affect the size and nature of the subsequent feeding response, suggesting that feed-forward interactions occur between the taste of foods and gastrointestinal stimulation.
Nutrition and immunity in the elderly
Authors: Lesourd Bruno , Mazari Lynda
Published: February 2011

Immune function declines with age, leading to increased infection and cancer rates in aged individuals. In fact, recent progress in the study of immune ageing has introduced the idea that rather than a general decline in the functions of the immune system with age, immune ageing is mainly characterized by a progressive appearance of immune dysregulation throughout life. Changes appear earlier in life for cell-mediated immunity than for humoral immunity. Thus, agerelated modifications in cell-mediated immunity, i.e. changes in naive: memory T-cells, mature: immature T-cells, T-helper 1: T-helper 2 cells are more important in the elderly than changes in humoral immunity, i.e. CD5: CD5+ cells or length of antibody responses. Such evolution of the immune system has been linked to declining thymus function and to accumulative antigenic influence over the lifespan. In contrast, innate immunity (macrophage functions) is preserved or even increased during the ageing process. This finding shows that the ‘primitive’ immune system is less affected by the ageing process than the sophisticated specific immune system. The present review focuses on innate and cell-mediated immune changes with ageing. It provides evidence that primary changes (intrinsic modifications in the immune system) and secondary changes (resulting from environmental influences during the lifespan) exert different influences on the immune system. Primary changes, occurring in healthy individuals, seem less important nowadays than they were considered to be previously. For example, interleukin 2 secretion in some very healthy aged individuals is comparable with that in younger adults. Primary immune changes may not explain the increased incidence and severity of infections observed in the elderly population. Secondary immunological changes are far more frequent and are certainly responsible for most of the immune modifications observed in the elderly population. Environmental factors leading to secondary immune dysfunctions include not only antigenic influence, which is a reflection of diseases experienced over the lifespan, but also many other factors such as drug intake, physical activity and diet; factors for which important changes occur in the elderly population. Nutritional factors play a major role in the immune responses of aged individuals and the present review shows that nutritional influences on immune responses are of great consequence in aged individuals, even in the very healthy elderly.
Nutrition and immune function in human immunodeficiency virus infection
Authors: Macallan Derek C.
Published: February 2011

The triad of human immunodeficiency virus (HIV) infection, nutritional status and immune function are intimately related, each factor having effects on the others. The dominant effect in this three-way relationship is the effect of HIV infection on nutritional status, an effect which, until the advent of potent anti-retroviral drugs, has been manifest primarily as wasting. Recently, more complex metabolic abnormalities have become apparent, particularly fat redistribution syndromes, hyperlipidaemia and hypercholesterolaemia. For the converse effect, the effect of nutritional state on HIV disease progression, there is good evidence that clinical outcome is poorer in individuals with compromised nutrition. However, the beneficial effects of nutritional support have been more difficult to demonstrate. For macronutrients, effective macronutrient supply improves survival in severely-malnourished individuals and may have beneficial effects in less-severely-affected individuals. Micronutrient deficiencies appear to be involved in modifying clinical HIV disease and may also be associated with enhanced mother-to-child transmission of virus, particularly in developing countries. Intervention trials in this setting are currently under way. In conclusion, the interaction of HIV infection and nutrition is of great importance not just because of the major impact that HIV infection has on nutritional state, but also because strategies to improve nutritional status, both quantitatively and qualitatively, may have a beneficial effect on the clinical and immunological course of the disease.
Enhancing computer self-efficacy and attitudes in multi-ethnic older adults: a randomised controlled study
Authors: LAGANÁ LUCIANA , OLIVER TAYLOR , AINSWORTH ANDREW , EDWARDS MARC
Published: February 2011

Several studies have documented the health-related benefits of older adults' use of computer technology, but before they can be realised, older individuals must be positively inclined and confident in their ability to engage in computer-based environments. To facilitate the assessment of computer technology attitudes, one aim of the longitudinal study reported in this article was to test and refine a new 22-item measure of computer technology attitudes designed specifically for older adults, as none such were available. Another aim was to replicate, on a much larger scale, the successful findings of a preliminary study that tested a computer technology training programme for older adults. Ninety-six older men and women, mainly from non-European-American backgrounds, were randomly assigned to the waitlist/control or the experimental group. The same six-week, one-on-one training was administered to the control subjects at the completion of their post-test. The revised (17-item) version of the Older Adults' Computer Technology Attitudes Scale (OACTAS) showed strong reliability: the results of a factor analysis were robust, and two analyses of covariance demonstrated that the training programme induced significant changes in attitudes and self-efficacy. Such results encourage the recruitment of older persons into training programmes aimed at increasing computer technology attitudes and self-efficacy.
Type synthesis of parallel mechanisms having the first class GF sets and one-dimensional rotation
Authors: Yang Jialun , Gao Feng , Ge Qiaode Jeffrey , Zhao Xianchao , Guo Weizhong , Jin Zhenlin
Published: February 2011

A method is presented for the type synthesis of a class of parallel mechanisms having one-dimensional (1D) rotation based on the theory of Generalized Function sets (GF sets for short), which contain two classes. The type synthesis of parallel mechanisms having the first class GF sets and 1D rotation is investigated. The Law of one-dimensional rotation is given, which lays the theoretical foundation for the intersection operations of GF sets. Then the kinematic limbs with specific characteristics are designed according to the 2D and 3D axis movement theorems. Finally, several synthesized parallel mechanisms have been sketched to show the effectiveness of the proposed methodology.
Catastrophic haemoptysis in the Fontan circulation – a novel surgical approach to denude the culprit bleeding vessels
Authors: Black David E. , Veldtman Gruschen R. , Bryant Timothy , Miller John , Haw Marcus
Published: February 2011

We describe the case of a young man aged 19 years with a double inlet left ventricle associated with transposition of the great arteries, and a mechanical aortic valve requiring anticoagulation, who presented with massive haemoptysis. At cardiac catheterisation, there were multiple feeder vessels to a bleeding leash surrounding and communicating with his left main bronchus. Despite occlusion of the larger feeder vessels, he continued to have massive haemoptysis. We describe a novel surgical strategy of denuding the peribronchial vessels through a left lateral thoracotomy. This successfully stopped his bleeding.
Transgressive Sound Surrogacy
Authors: Pedersen Michael
Published: February 2011

This four-part exposition revisits Denis Smalley's concept of sound surrogacy from a critical constructive approach. In the first part, Smalley's article from 1997 serves as a point of origin for a close investigation of his concept. We examine the precise definitions and demarcations in his concepts and we attempt to systematise the model. In the second part of the investigation we attempt to solve some of the problems in Smalley's model by suggesting a new surrogacy model originating in Smalley's idea, but with a more formal structure and obvious demarcations. Having presented this new surrogacy model, with references to Georges Bataille's theories on base materialism as well as anthropological studies, we attempt to create a new order of surrogacy that in its object relation is positioned beneath Smalley's first-order surrogacy (as the remote surrogacy order is placed above the third-order surrogacy) – an impossible/paradoxical category that will be termed transgressive sound surrogacy. In the fourth part we demonstrate this new surrogacy order in a series of examples found in art and culture.
Extra-Musical Meanings and Spectromorphology
Authors: Tanzi Dante
Published: February 2011

Denis Smalley devoted himself to the elaboration of a method based on the analysis of spectral transformations by connoting sonorous motions and adopting metaphors borrowed from non-musical contexts. While considering Smalley's earlier theorising within the context of past and contemporary research, this paper focuses on the use of non-musical models in spectromorphological design in order to show how sonorous qualities, imaginative factors and extra-musical meanings concurred in defining new cognitive itineraries and in extending the terminology adopted, thereby establishing the basis of a new compositional approach.