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Title:
Two common single nucleotide polymorphisms in the gene encoding beta-carotene 15,15'-monoxygenase alter beta-carotene metabolism in female volunteers
Authors:
Leung, W. C.; Hessel, S.; Méplan, C.; Flint, J.; Oberhauser, V.; Tourniaire, F.; Hesketh, J. E.; von Lintig, J.; Lietz, G.
Abstract:
The key enzyme responsible for beta-carotene conversion into retinal is beta-carotene 15,15'-monoxygenase (BCMO1). Since it has been reported that the conversion of beta-carotene into vitamin A is highly variable in up to 45% of healthy individuals, we hypothesized that genetic polymorphisms in the BCMO1 gene could contribute to the occurrence of the poor converter phenotype. Here we describe the screening of the total open reading frame of the BCMO1 coding region that led to the identification of two common nonsynonymous single nucleotide polymorphisms (R267S: rs12934922; A379V: rs7501331) with variant allele frequencies of 42 and 24%, respectively. In vitro biochemical characterization of the recombinant 267S + 379V double mutant revealed a reduced catalytic activity of BCMO1 by 57% (P
Published:
2009-04
Title:
A moderate-protein diet produces sustained weight loss and long-term changes in body composition and blood lipids in obese adults
Authors:
Layman, Donald K.; Evans, Ellen M.; Erickson, Donna; Seyler, Jennifer; Weber, Judy; Bagshaw, Deborah; Griel, Amy; Psota, Tricia; Kris-Etherton, Penny
Abstract:
Diets with increased protein and reduced carbohydrates (PRO) are effective for weight loss, but the long-term effect on maintenance is unknown. This study compared changes in body weight and composition and blood lipids after short-term weight loss (4 mo) followed by weight maintenance (8 mo) using moderate PRO or conventional high-carbohydrate (CHO) diets. Participants (age = 45.4 +/- 1.2 y; BMI = 32.6 +/- 0.8 kg/m(2); n = 130) were randomized to 2 energy-restricted diets (-500 kcal/d or -2093 kJ/d): PRO with 1.6 g x kg(-1) x d(-1) protein and 220 g/d carbohydrates. At 4 mo, the PRO group had lost 22% more fat mass (FM) (-5.6 +/- 0.4 kg) than the CHO group (-4.6 +/- 0.3 kg) but weight loss did not differ between groups (-8.2 +/- 0.5 kg vs. -7.0 +/- 0.5 kg; P = 0.10). At 12 mo, the PRO group had more participants complete the study (64 vs. 45%, P 10% weight loss, the PRO group had more participants (31 vs. 21%) lose more weight (-16.5 +/- 1.5 vs. -12.3 +/- 0.9 kg; P < 0.01) and FM (-11.7 +/- 1.0 vs. -7.9 +/- 0.7 kg; P < 0.01) than the CHO group. The CHO diet reduced serum cholesterol and LDL cholesterol compared with PRO (P < 0.01) at 4 mo, but the effect did not remain at 12 mo. PRO had sustained favorable effects on serum triacylglycerol (TAG), HDL cholesterol (HDL-C), and TAG:HDL-C compared with CHO at 4 and 12 mo (P
Published:
2009-03
Title:
ADHD as a (non) allergic hypersensitivity disorder: a hypothesis
Authors:
Pelsser, Lidy M. J.; Buitelaar, Jan K.; Savelkoul, Huub F. J.
Abstract:
Research data concerning the causal association between attention deficit hyperactivity disorder (ADHD) and allergies are conflicting. Allergic disorders, like asthma and eczema are clinical syndromes in which both genetic predisposition and environmental factors (pets, pollen and foods) contribute to its development. The hypothesis of ADHD, in some children also being an allergic disorder, is postulated based on comparison of the mechanisms underlying the development of ADHD and allergic disorders. According to the accepted terminology, ADHD may comply with the criteria of hypersensitivity, allergy and atopy. This hypothesis has to be thoroughly tested by randomized controlled trials using environmental triggers and immunologic research. As genes related to the immune system may be associated with ADHD, further genetic research is compulsory. Immunotherapeutic approaches, using immunotherapy and probiotics, can subsequently be implicated in the treatment of ADHD. If hypersensitivity to environmental stimuli like foods contributes to the development of ADHD, the assessment and treatment of ADHD will have to be reconsidered, thereby improving the quality of care for these patients.
Published:
2009-03
Title:
Effect of a Klamath algae product ("AFA-B12") on blood levels of vitamin B12 and homocysteine in vegan subjects: a pilot study
Authors:
Baroni, Luciana; Scoglio, Stefano; Benedetti, Serena; Bonetto, Chiara; Pagliarani, Silvia; Benedetti, Yanina; Rocchi, Marco; Canestrari, Franco
Abstract:
Vitamin B12 is a critical nutrient that is often inadequate in a plant-based (vegan) diet, thus the inclusion of a reliable vitamin B12 source in a vegan diet is recommended as essential. Unfortunately, many natural sources of vitamin B12 have been proven to contain biologically inactive vitamin B12 analogues, inadequate for human supplementation. The aim of this non-randomized open trial was to determine whether supplementation with a natural Klamath algae-based product ("AFA-B12", Aphanizomenon flos-aquae algae plus a proprietary mix of enzymes) could favorably affect the vitamin B12 status of a group of 15 vegan subjects. By assessing blood concentration of vitamin B12, folate, and more importantly homocysteine (Hcy, a reliable marker in vegans of their B12 absorption), the vitamin B12 status of the participants at the end of the 3-month intervention period, while receiving the Klamath-algae supplement (T2), was compared with their vitamin B12 status at the end of the 3-month control period (T1), when they were not receiving any supplement, having stopped taking their usual vitamin B12 supplement at the beginning of the study (T0). Compared to the control period, in the intervention period participants improved their vitamin B12 status, significantly reducing Hcy blood concentration (p=0.003). In conclusion, the Klamath algae product AFA-B12 appears to be, in a preliminary study, an adequate and reliable source of vitamin B12 in humans.
Published:
2009-03
Title:
Increasing the resolution of the Broad Spectrum Revolution in the Southern Levantine Epipaleolithic (19–12 ka)
Authors:
Stutz, Aaron Jonas; Munro, Natalie D.; Bar-Oz, Guy
Abstract:
We analyze terminal Pleistocene archaeofaunal diversity trends in the Southern Levant by examining eight Epipaleolithic (ca. 19–12 ka) assemblages from the Western Galilee/Mt. Carmel, Israel subregion. We test predictions from a Broad Spectrum Revolution model of the population dynamics of human foragers and their prey. The study emphasizes control over geographic variability and archaeological recovery and recording methods, as we analyze a time series that samples the Epipaleolithic more fully than have previous studies. This provides a new opportunity to examine human population and economic change in the long-term transition to sedentism and agriculture. We use the Mantel test to evaluate the significance of temporal trends in body-size-based big game diversity, as well as in diversity of small game prey types. Results demonstrate a highly significant decline through time in the relative abundance of medium and large big game, measured relative to small big game. This suggests that the apparent “gazelle specialization” by Late Epipaleolithic (Natufian) hunters reflects longer-term anthropogenic overexploitation of the largest prey types in the spectrum. While large and medium big game abundance declined, our results show small game increased in economic importance over time. Considered with associated climate change data, the results provide substantial support for the hypothesis that local human populations expanded rapidly in size after the Last Glacial Maximum (LGM). We suggest that following the post-LGM population pulse, human foragers adopted a shifting series of intensification strategies mediated by changes in residential mobility.
Published:
2009-03
Title:
On stone-boiling technology in the Upper Paleolithic: behavioral implications from an Early Magdalenian hearth in El Mirón Cave, Cantabria, Spain
Authors:
Nakazawa, Yuichi; Straus, Lawrence G.; González-Morales, Manuel R.; Solana, David Cuenca; Saiz, Jorge Caro
Abstract:
Stone boiling is one of the principal cooking methods used by hunter-gatherer societies. The present paper proposes behavioral and organizational inferences as to how stone boiling was incorporated into hunter-gatherer subsistence practices through an examination of a shallow-basin hearth in an Early Magdalenian level (c. 15,500 14C B.P.) of El Mirón Cave, Cantabria (northern Spain). Exploratory analysis of spatial patterns of archaeological remains (bones, lithic artifacts, and fire-cracked rocks) and use-life analysis of fire-cracked rocks demonstrate that the hearth was used and maintained during visits of humans who preyed mainly on ibex and red deer near the site. The relative accessibility of these ungulates and cost-induced technology of stone boiling suggest the implication that stone boiling was employed to maximize the energy and nutrition obtained from carcasses of these game taxa under the circumstance of resource intensification.
Published:
2009-03
Title:
THE NEUROPROTECTIVE PROPERTIES OF CALORIE RESTRICTION, THE KETOGENIC DIET, AND KETONE BODIES
Authors:
Maalouf, Marwan A.; Rho, Jong M.; Mattson, Mark P.
Abstract:
The therapeutic potential of calorie restriction and the ketogenic diet have been repeatedly demonstrated in clinical settings and in various animal models of neurological disease. The underlying mechanisms involve an improvement in mitochondrial function, a decrease in the expression of apoptotic factors and an increase in the activity of neurotrophic factors. Clinical applications of ketogenic diets have been significantly hampered however by poor tolerability and potentially serious side-effects. Recent research aimed at identifying a mediator that can reproduce the neuroprotective effects of calorie restriction with less demanding changes to dietary intake suggests that ketone bodies might represent an appropriate candidate. Ketone bodies protect neurons against multiple types of neuronal injury and the underlying mechanisms are similar to those of calorie restriction and of the ketogenic diet. The present review describes the neuroprotective effects of calorie restriction, the ketogenic diet and ketone bodies and compare the molecular mechanisms of action of these interventions.
Published:
2009-03
Title:
The triglyceride/high-density lipoprotein cholesterol ratio predicts all-cause mortality in women with suspected myocardial ischemia: a report from the Women's Ischemia Syndrome Evaluation (WISE)
Authors:
Bittner, Vera; Johnson, B. Delia; Zineh, Issam; Rogers, William J.; Vido, Diane; Marroquin, Oscar C.; Bairey-Merz, C. Noel; Sopko, George
Abstract:
High triglycerides (TG) and low high-density lipoprotein cholesterol (HDL-C) are important cardiovascular risk factors in women. The prognostic utility of the TG/HDL-C ratio, a marker for insulin resistance and small dense low-density lipoprotein particles, is unknown among high-risk women. METHODS: We studied 544 women without prior myocardial infarction or coronary revascularization, referred for clinically indicated coronary angiography and enrolled in the Women's Ischemia Syndrome Evaluation (WISE). Fasting lipid profiles and detailed demographic and clinical data were obtained at baseline. Multivariate Cox-proportional hazards models for all-cause mortality and cardiovascular events (death, myocardial infarction, heart failure, stroke) over a median follow-up of 6 years were constructed using log TG/HDL-C ratio as a predictor variable and accounting for traditional cardiovascular risk factors. RESULTS: Mean age was 57 +/- 11 years; 84% were white, 55% hypertensive, 20% diabetic, 50% current or prior smokers. Triglyceride/HDL-C ranged from 0.3 to 18.4 (median 2.2, first quartile 0.35 to <1.4, fourth quartile 3.66-18.4). Deaths (n = 33) and cardiovascular events (n = 83) increased across TG/HDL-C quartiles (both P
Published:
2009-03
Title:
Total red blood cell concentrations of omega-3 fatty acids are associated with emotion-elicited neural activity in adolescent boys with attention-deficit hyperactivity disorder
Authors:
Gow, Rachel V.; Matsudaira, Toshiko; Taylor, Eric; Rubia, Katya; Crawford, Michael; Ghebremeskel, Kebreab; Ibrahimovic, Almira; Vallée-Tourangeau, Frédéric; Williams, Leanne M.; Sumich, Alexander
Abstract:
Affective impairment is observed in children and adolescents with attention-deficit hyperactivity disorder (ADHD). Low levels of long-chain polyunsaturated fatty acids (LC-PUFA), specifically omega-3 (omega-3) fatty acids in blood measures have been linked to a range of behavioural and mood disorders including ADHD. However, nothing is known about the relationship between omega-3 and brain function in children with ADHD. In the current study, 20 adolescent boys with ADHD were assessed for total lipid fractions in red blood cells and their event-related potential (ERP) response to the presentation of facial expressions of happiness, sadness and fearfulness. The results supported the hypothesis of a positive association between eicosapentaenoic acid (EPA) and a cognitive bias in orientation to overt expressions of happiness over both sad and fearful faces as indexed by midline frontal P300 amplitude. Additional exploratory analyses revealed a positive association between levels of docosahexaenoic acid (DHA) and the right temporal N170 amplitude in response to covert expressions of fear. The arachidonic (AA)/DHA ratio was negatively associated with the right temporal N170 amplitude also to covert expressions of fear. These findings indicate that EPA and DHA may be involved in distinct aspects of affect processing in ADHD and have implications for understanding currently inconsistent findings in the literature on EFA supplementation in ADHD and depression.
Published:
2009-03
Title:
[Effect of vitamin D supplementation on serum 25-hydroxyvitamin D and bone turnover markers concentrations in vegetarian children]
Authors:
Ambroszkiewicz, Jadwiga; Klemarczyk, Witold; Gajewska, Joanna; Chełchowska, Magdalena; Strucińska, Małgorzata; Ołtarzewski, Mariusz; Laskowska-Klita, Teresa
Abstract:
PURPOSE: Vitamin D plays a key role in bone mineralization by regulating calcium and phosphate metabolism. Deficiency of this vitamin may lead to disturbances in bone metabolism as well as to osteopenia and osteoporosis. AIM: 1. Assessment of daily intake of calcium and vitamin D in children on vegetarian diet. 2. Measurement of serum 25-hydroxyvitamin D and biochemical bone turnover markers levels in vegetarian children supplemented with calcium and vitamin D, before and after the intervention. MATERIAL AND METHODS: We examined 35 prepubertal children on vegetarian diet who were divided into two groups: group A (without supplementation) and group B in which the children received daily 400 IU vitamin D3 and 500 mg calcium. Total serum calcium, phosphate, 25-hydroxyvitamin D and bone turnover markers were measured at start and end of the intervention. RESULTS: Concentration of calcium and phosphate in serum of all tested children were within physiological range. The mean value of 25-hydroxyvitamin D at start of supplementation was low in both the vitamin D-treated group and in the controls (about 19 ng/ml). After 4-months supplementation, the vitamin D level was significantly higher in the vitamin D-treated group (38.3+/-8.5 ng/ml) than in the control group (13.7+/-5.3 ng/ml) (p
Published:
2009-03
Title:
A low-fat vegan diet elicits greater macronutrient changes, but is comparable in adherence and acceptability, compared with a more conventional diabetes diet among individuals with type 2 diabetes
Authors:
Barnard, Neal D.; Gloede, Lise; Cohen, Joshua; Jenkins, David J. A.; Turner-McGrievy, Gabrielle; Green, Amber A.; Ferdowsian, Hope
Abstract:
BACKGROUND: Although therapeutic diets are critical to diabetes management, their acceptability to patients is largely unstudied. OBJECTIVE: To quantify adherence and acceptability for two types of diets for diabetes. DESIGN: Controlled trial conducted between 2004 and 2006. SUBJECTS/SETTING: Individuals with type 2 diabetes (n=99) at a community-based research facility. Participants were randomly assigned to a diet following 2003 American Diabetes Association guidelines or a low-fat, vegan diet for 74 weeks. MAIN OUTCOME MEASURES: Attrition, adherence, dietary behavior, diet acceptability, and cravings. STATISTICAL ANALYSES: For nutrient intake and questionnaire scores, t tests determined between-group differences. For diet-acceptability measures, the related samples Wilcoxon sum rank test assessed within-group changes; the independent samples Mann-Whitney U test compared the diet groups. Changes in reported symptoms among the groups was compared using chi(2) for independent samples. RESULTS: All participants completed the initial 22 weeks; 90% (45/50) of American Diabetes Association guidelines diet group and 86% (42/49) of the vegan diet group participants completed 74 weeks. Fat and cholesterol intake fell more and carbohydrate and fiber intake increased more in the vegan group. At 22 weeks, group-specific diet adherence criteria were met by 44% (22/50) of members of the American Diabetes Association diet group and 67% (33/49) of vegan-group participants (P=0.019); the American Diabetes Association guidelines diet group reported a greater increase in dietary restraint; this difference was not significant at 74 weeks. Both groups reported reduced hunger and reduced disinhibition. Questionnaire responses rated both diets as satisfactory, with no significant differences between groups, except for ease of preparation, for which the 22-week ratings marginally favored the American Diabetes Association guideline group. Cravings for fatty foods diminished more in the vegan group at 22 weeks, with no significant difference at 74 weeks. CONCLUSIONS: Despite its greater influence on macronutrient intake, a low-fat, vegan diet has an acceptability similar to that of a more conventional diabetes diet. Acceptability appears to be no barrier to its use in medical nutrition therapy.
Published:
2009-02
Title:
Comparative efficacy and acceptability of 12 new-generation antidepressants: a multiple-treatments meta-analysis
Authors:
Cipriani, Andrea; Furukawa, Toshiaki A; Salanti, Georgia; Geddes, John R; Higgins, Julian PT; Churchill, Rachel; Watanabe, Norio; Nakagawa, Atsuo; Omori, Ichiro M; McGuire, Hugh; Tansella, Michele; Barbui, Corrado
Abstract:
Background Conventional meta-analyses have shown inconsistent results for efficacy of second-generation antidepressants. We therefore did a multiple-treatments meta-analysis, which accounts for both direct and indirect comparisons, to assess the effects of 12 new-generation antidepressants on major depression.
Published:
2009-02
Title:
Conference on "Multidisciplinary approaches to nutritional problems". Symposium on "Nutrition and health". Cruciferous vegetable intake and the risk of human cancer: epidemiological evidence
Authors:
Kim, Mi Kyung; Park, Jung Han Yoon
Abstract:
Over several decades a number of epidemiological studies have identified the inverse associations between cruciferous vegetables and the risk of several cancers, including gastric, breast, colo-rectal, lung, prostate, bladder and endometrial cancers, via plausible physiological mechanisms. Although retrospective case-control studies have consistently reported inverse associations between the risk of these cancers and the intake of cruciferous vegetables and isothiocyanate-containing plants, current prospective cohort studies have found these associations to be weaker and less consistent. Genetic variations affecting the metabolism of glucosinolate hydrolysis products may modulate the effects of cruciferous vegetable consumption on cancer risk, which may be one of the reasons for the discrepancies between retrospective and prospective studies. In addition, methodological issues such as measurement errors of dietary exposure, misclassification, recall bias, publication bias, confounding and study design should be carefully considered in interpreting the results of case-control and cohort studies and in drawing conclusions in relation to the potential effects of cruciferous vegetables on cancers. Although recent comprehensive reviews of numerous studies have purported to show the specific protective role of cruciferous vegetables, and particularly Brassicas, against cancer risk, the current epidemiological evidence suggests that cruciferous vegetable consumption may reduce the risk only of gastric and lung cancers. However, there is at present no conclusive evidence that the consumption of cruciferous vegetables attenuates the risk of all other cancers.
Published:
2009-02
Title:
Early hyperandrogenism affects the development of hippocampal function: preliminary evidence from a functional magnetic resonance imaging study of boys with familial male precocious puberty
Authors:
Mueller, Sven C; Mandell, Darcy; Leschek, Ellen W; Pine, Daniel S; Merke, Deborah P; Ernst, Monique
Abstract:
The way in which sex hormones influence cognitive and affective brain development is poorly understood. Despite increasing knowledge in the area of pediatric mood disorders, little is known about the influence of sex hormones on the regulation of emotion. Animal studies and preliminary human studies suggest a strong impact of testosterone on limbic structures such as the hippocampus and amygdala. We used functional magnetic resonance imaging (fMRI) to examine emotional processing in familial male-precocious puberty (FMPP), an extremely rare gonadotropin-independent form of precocious puberty characterized by early excess testosterone secretion. We compared this group (n = 7, mean age = 13 +/- 3.3 years) to healthy age and sex-matched controls (n = 14, mean age = 13 +/- 2.3 years). Participants were presented with emotional and neutral face stimuli and were required either to judge the hostility of the presented face, their subjective level of anxiety, or the width of the nose of the presented faces (nonemotional condition). In a fourth, passive viewing condition, no responses were required. Boys with FMPP responded faster to fearful faces during perception of threat compared to unaffected controls. Concurrently, fMRI data revealed significant differences in hippocampus activation in response to fearful faces relative to baseline whereas controls showed no differences. In contrast, no significant activation of the amygdala was found. These data are consistent with previous studies of the effects of sex hormones on brain function and support the role of testosterone on emotional development.
Published:
2009-02
Title:
Legume-, fish-, or high-protein-based hypocaloric diets: effects on weight loss and mitochondrial oxidation in obese men
Authors:
Abete, Itziar; Parra, Dolores; Martinez, J. Alfredo
Abstract:
The nutritional composition of dietary intake could produce specific effects on metabolic variables such as mitochondrial oxidation, whose understanding could contribute to apply more individualized weight-lowering strategies. This study assessed the effects of four hypocaloric diets with high protein content or different food distribution on metabolic changes and mitochondrial oxidation accompanying weight loss. Thirty-five obese men (body mass index of 31.8 +/- 3.0 kg/m(2) and 38 +/- 7 years old) were randomly assigned to one of the four treatments (8 weeks): control diet (C-diet); legume diet (L-diet); fatty fish diet (FF-diet); or high-protein diet (HP-diet). Body composition, blood pressure, resting energy expenditure, mitochondrial oxidation, blood biomarkers, and dietary intake were assessed. The HP-diet and L-diet achieved the greater body weight reduction (-8.4 +/- 1.2% and -8.3 +/- 2.9%, respectively), as compared to the C-diet (-5.5 +/- 2.5%; P = .042). The high-density lipoprotein cholesterol concentrations were reduced in all dietary groups except for the FF-diet. Total and low-density lipoprotein cholesterol levels were significantly improved by the L-diet (P
Published:
2009-02
Title:
Optimal clinical management of children receiving the ketogenic diet: recommendations of the International Ketogenic Diet Study Group
Authors:
Kossoff, Eric H.; Zupec-Kania, Beth A.; Amark, Per E.; Ballaban-Gil, Karen R.; Christina Bergqvist, A. G.; Blackford, Robyn; Buchhalter, Jeffrey R.; Caraballo, Roberto H.; Helen Cross, J.; Dahlin, Maria G.; Donner, Elizabeth J.; Klepper, Joerg; Jehle, Rana S.; Kim, Heung Dong; Christiana Liu, Y. M.; Nation, Judy; Nordli, Douglas R.; Pfeifer, Heidi H.; Rho, Jong M.; Stafstrom, Carl E.; Thiele, Elizabeth A.; Turner, Zahava; Wirrell, Elaine C.; Wheless, James W.; Veggiotti, Pierangelo; Vining, Eileen P. G.; Charlie Foundation, Practice Committee of the Child Neurology Society; Practice Committee of the Child Neurology Society; International Ketogenic Diet Study Group
Abstract:
The ketogenic diet (KD) is an established, effective nonpharmacologic treatment for intractable childhood epilepsy. The KD is provided differently throughout the world, with occasionally significant variations in its administration. There exists a need for more standardized protocols and management recommendations for clinical and research use. In December 2006, The Charlie Foundation commissioned a panel comprised of 26 pediatric epileptologists and dietitians from nine countries with particular expertise using the KD. This group was created in order to create a consensus statement regarding the clinical management of the KD. Subsequently endorsed by the Practice Committee of the Child Neurology Society, this resultant manuscript addresses issues such as patient selection, pre-KD counseling and evaluation, specific dietary therapy selection, implementation, supplementation, follow-up management, adverse event monitoring, and eventual KD discontinuation. This paper highlights recommendations based on best evidence, including areas of agreement and controversy, unanswered questions, and future research.
Published:
2009-02
Title:
Oral detection of short-, medium-, and long-chain free fatty acids in humans
Authors:
Mattes, Richard D.
Abstract:
There is increasing evidence supporting an oral chemosensory detection system for free fatty acids (FFA). The presumptive transduction mechanisms have different ligand specificities. Psychophysical studies with FFA varying in chain length and saturation may aid in identifying the presence and functionality of these mechanisms in humans. Oral detection thresholds were measured for linoleic, stearic, lauric, and caproic acids in 32 healthy adults by an ascending, 3-alternative, forced-choice, sip and spit procedure. Thresholds were obtained for all fatty acids from all participants, but the distributions were wide and nonnormal. Thresholds were not correlated between fatty acids nor with thresholds for sucrose (taste), butanol (olfactory), mineral oil, or gum acacia (both somatosensory). These data demonstrate human oral sensitivity to short-, medium-, and long-chain FFA and suggest the presence of multiple transduction mechanisms. The findings are consistent with, but do not definitively demonstrate, a role for taste that may have a genetic basis.
Published:
2009-02
Title:
Regular consumption of n-3 fatty acid-enriched pork modifies cardiovascular risk factors
Authors:
Coates, Alison M.; Sioutis, Stelios; Buckley, Jonathan D.; Howe, Peter R. C.
Abstract:
The long-chain (LC) n-3 PUFA content of pork, particularly DHA, can be increased by including 15% PorcOmega (a fortified tuna fishmeal product) in pig finisher diets. The aim of the present study was to see whether this enriched pork could deliver cardiovascular health benefits to consumers. In a double-blind intervention trial, thirty-three healthy adult volunteers (sixteen female and seventeen male) were randomised to consume either n-3-enriched or regular (control) pork (a selection of five fresh cuts totalling 1000 g/week) for 12 weeks. Fasting blood samples were collected every 4 weeks and analysed for serum lipids, maximally stimulated thromboxane production and erythrocyte fatty acid composition. The n-3-enriched pork provided subjects with 1.3 g LC n-3 PUFA per week. Erythrocyte DHA levels rose 15% in the n-3 group and fell 5% in the control group over 12 weeks (P=0.001). Compared with the control group, serum TAG decreased to a greater extent in the n-3 group (P=0.02) and serum thromboxane production increased to a lesser extent (P=0.004). Changes in the latter were inversely associated with changes in incorporation of DHA into erythrocytes (r -0.54; P
Published:
2009-02
Title:
Systematic review of randomized controlled trials of low-carbohydrate vs. low-fat/low-calorie diets in the management of obesity and its comorbidities
Authors:
Hession, M.; Rolland, C.; Kulkarni, U.; Wise, A.; Broom, J.
Abstract:
There are few studies comparing the effects of low-carbohydrate/high-protein diets with low-fat/high-carbohydrate diets for obesity and cardiovascular disease risk. This systematic review focuses on randomized controlled trials of low-carbohydrate diets compared with low-fat/low-calorie diets. Studies conducted in adult populations with mean or median body mass index of > or =28 kg m(-2) were included. Thirteen electronic databases were searched and randomized controlled trials from January 2000 to March 2007 were evaluated. Trials were included if they lasted at least 6 months and assessed the weight-loss effects of low-carbohydrate diets against low-fat/low-calorie diets. For each study, data were abstracted and checked by two researchers prior to electronic data entry. The computer program Review Manager 4.2.2 was used for the data analysis. Thirteen articles met the inclusion criteria. There were significant differences between the groups for weight, high-density lipoprotein cholesterol, triacylglycerols and systolic blood pressure, favouring the low-carbohydrate diet. There was a higher attrition rate in the low-fat compared with the low-carbohydrate groups suggesting a patient preference for a low-carbohydrate/high-protein approach as opposed to the Public Health preference of a low-fat/high-carbohydrate diet. Evidence from this systematic review demonstrates that low-carbohydrate/high-protein diets are more effective at 6 months and are as effective, if not more, as low-fat diets in reducing weight and cardiovascular disease risk up to 1 year. More evidence and longer-term studies are needed to assess the long-term cardiovascular benefits from the weight loss achieved using these diets.
Published:
2009-01
Title:
11-year follow-up of mortality in patients with schizophrenia: a population-based cohort study (FIN11 study)
Authors:
Tiihonen, Jari; Lã, Jouko
Abstract:
Background The introduction of second-generation antipsychotic drugs during the 1990s is widely believed to have adversely affected mortality of patients with schizophrenia. Our aim was to establish the long-term contribution of antipsychotic drugs to mortality in such patients.
Published:
2009
Title:
A Modified Nonequilibrium pH Gradient Electrophoresis (NEPHGE) Technique for Protein Separation
Authors:
Carroll, James A.
Abstract:
Membrane proteins, hydrophobic proteins, and proteins with alkaline isoelec-tric points (pIs) traditionally have been difficult to visualize by two-dimensional (2-D) gel electrophoresis. There are a multitude of reason as to why proteins with basic pIs (many of them membrane proteins) are difficult to resolve by standard IEF methods: (i) the lack of pH gradient formation above pH 7.6 due to the buffering effect of urea, (ii) precipitation of proteins when entering the gel and during focusing, (iii) cathodic drift during focusing resulting in the migration of basic proteins off the ends of the tube gels, or (iv) lack of solubility in particular nonionic detergents. O’Farrell et al. first reported in 1977 a novel protein separation technique termed Nonequilibrium pH Gradient Electrophoresis (NEPHGE) as a method to enhance the separation of proteins with significantly basic pIs (1), but this alternative technique had its limitations due to issues with reproducibility with the reagents of that era. With the advent of new compounds for the solubili-zation of recalcitrant proteins, my laboratory has made minor modifications to the original NEPHGE protocol reported by O’Farrell offering enhanced reproducibility with increased solubilization of alkaline and membrane proteins (2–4).
Published:
2009
Title:
A model for determining total ketogenic ratio (TKR) for evaluating the ketogenic property of a weight-reduction diet
Authors:
Cohen, I. A.
Abstract:
Ketogenic weight-reduction dieting methods have existed since antiquity. Recent research has demonstrated their value in controlling type 2 diabetes. Although research done in the 1920s provided a mathematical model of non-weight-reduction ketogenic clinical diets using the concept of a ketogenic ratio (KR), little has been done to evaluate the ketogenic nature of purported ketogenic weight-reduction diets. The mathematical model of Woodyatt is valid only under isocaloric conditions where dietary energy intake is balanced by energy use. It is hypothesised that under certain conditions of weight loss, energy deficit can predict utilization of stored lipid so that a modified formula for total ketogenic ratio (TKR) may be derived. Such a predictive mathematical model may be a useful tool in predicting the efficacy of weight-reduction diets and adapting such diets to individual patient needs. © 2009 Elsevier Ltd. All rights reserved.
Published:
2009
Title:
APC and its modifiers in colon cancer
Authors:
Kwong, Lawrence N.; Dove, William F.
Abstract:
Colon cancer closely follows the paradigm of a single “gatekeeper gene.” Mutations inactivating the APC (adenomatous polyposis coli) gene are found in ~80% of all human colon tumors, and heterozygosity for such mutations produces an autosomal dominant colon cancer predisposition in humans and in murine models. However, this tight association between a single genotype and phenotype belies a complex association of genetic and epigenetic factors that together generate the broad phenotypic spectrum of both familial and sporadic colon cancers. In this Chapter, we give a general overview of the structure, function, and outstanding issues concerning the role of Apc in human and experimental colon cancer. The availability of increasingly close models for human colon cancer in genetically tractable animal species enables the discovery and eventual molecular identification of genetic modifiers of the Apc-mutant phenotypes, connecting the central role of Apc in colon carcinogenesis to the myriad factors that ultimately determine the course of the disease.
Published:
2009
Title:
Acetic Acid—Urea Polyacrylamide Gel Electrophoresis of Basic Proteins
Authors:
Waterborg, Jakob H.
Abstract:
Panyim and Chalkley described in 1969 a continuous acetic acid—urea (AU) gel system that could separate very similar basic proteins based on differences in size and effective charge (1). For instance, unmodified histone H4 can be separated from its monoacetylated or monophosphorylated forms (2). At the acidic pH 3 of this gel system, basic proteins with a high isoelectric point will clearly have a net positive charge that will be the major determinant of electro-phoretic mobility. If a single of these positive charges is removed, for example, by in vivo acetylation of one of the positively charged ε-amino lysine side chain residues in the small histone H4 protein (102 residues), a significant decrease in effective gel mobility is observed. Similarly, addition of a phosphate moiety decreases the net positive charge of the protein during gel electrophoresis by one. Separation between similarly sized and charged proteins, for example, the partially acetylated H2A, H2B, and H3 histones of most organisms, can typically be achieved only by inclusion of a nonionic detergent such as Triton X-100 (see Chapter 28).
Published:
2009
Title:
Acid—Urea—Triton Polyacrylamide Gel Electrophoresis of Histones
Authors:
Waterborg, Jakob H.
Abstract:
Acid-urea polyacrylamide gels are capable of separating basic histone proteins provided they differ sufficiently in size and/or effective charge (see Chapter 27). Separation between similarly sized and charged molecules, such as the histones H2A, H2B, and the H3 forms of most organisms, can typically not be achieved. Zweidler discovered that core histones but not linker histones (see Note 1) bind the nonionic detergent Triton (1). Generally, Triton is added to an acetic acid-urea (AU) gel system to separate core histone sequence variants and histone species with overlapping AU gel patterns. This type of gel is known as an AUT or a TAU gel. To date, a single example is known where addition of Triton X-100 has allowed separation of a nonhistone primary sequence variation, the hydrophobic replacement variant of phenylalanine by leucine in fetal hemoglobin (2).
Published:
2009
Title:
Adipose tissue remodeling in lipedema: adipocyte death and concurrent regeneration
Authors:
Suga, Hirotaka; Araki, Jun; Aoi, Noriyuki; Kato, Harunosuke; Higashino, Takuya; Yoshimura, Kotaro
Abstract:
Lipedema is a disease with unknown etiology presenting as bilateral and symmetric enlargement of the lower extremities due to subcutaneous deposition of the adipose tissue. Here we describe the histopathological features of the lipedema tissue and nonaffected adipose tissue obtained from a typical patient with severe lipedema. Immunohistochemical analyses indicated degenerative and regenerative changes of the lipedema tissue, characterized by crown-like structures (necrotizing adipocytes surrounded by infiltrating CD68+ macrophages; a feature commonly seen in obese adipose tissue) and proliferation of adipose-derived stem/progenitor/stromal cells (Ki67+CD34+ cells), respectively. These findings suggested increased adipogenesis in the lipedema tissue, which may further lead to hypoxia similar to that seen in obesity, resulting in adipocyte necrosis and macrophage recruitment. The confinement to the lower extremities and the difference from systemic obesity warrants further elucidation in future studies.
Published:
2009
Title:
Advanced glycation end products increase transglutaminase activity in primary porcine tenocytes
Authors:
Rosenthal, A.K.; Gohr, C.M.; Mitton, E.; Monnier, V.; Burner, T.
Abstract:
Objectives: Tendon abnormalities, such as increased stiffness, thickness, and excess calcification, occur commonly in patients with diabetes mellitus and cause considerable disability. These changes are frequently attributed to increased cross-linking of extracellular matrix components by advanced glycation end-products (AGEs). However, cellular effects of AGEs, such as increased activity of the cross-linking transglutaminase (Tgase) enzymes, could also contribute to altered tissue biomechanics and calcification in diabetic tendons. We determined the effect of AGE-modified protein on tenocyte Tgase activity. Research Design and Methods: Primary porcine tenocytes were exposed to N- carboxymethyl-lysine (CML)-modified type I collagen in high or normal glucose media. Protein and mRNA levels of the Tgase enzymes and Tgase activity levels were measured, as were markers of apoptosis. We also determined the effect of antioxidants on CML-collagen mediated Tgase activity. Results: Carboxymethyl-lysine-collagen increased Tgase activity in tenocytes 2.3- to 5.6-fold over unmodified collagen controls in both normal and high glucose media, without altering enzyme protein levels. Anti-oxidant treatment reduced the effect of CML-collagen on Tgase activity. Deoxyribonucleic acid laddering and annexin V protein levels were not altered by CML-collagen exposure. Conclusions: Carboxymethyl-lysine-collagen increased Tgase activity in tenocytes, likely posttranslationally. Increased levels of Tgase-mediated cross-links may contribute to the excess calcification and biomechanical pathology seen in diabetic tendons. Copyright © 2009 by The American Federation for Medical Research.
Published:
2009
Title:
Alcohol-use disorders
Authors:
Schuckit, Marc A
Abstract:
Published:
2009
Title:
Americans’ Attitudes Toward Psychiatric Medications: 1998–2006
Authors:
Mojtabai, Ramin
Abstract:
Published:
2009
Title:
Association of sleep duration with mortality from cardiovascular disease and other causes for japanese men and women: The JACC study
Authors:
Ikehara, Satovo; Iso, Hirovasu; Date, Ciqusa; Kikuchi, Shoao; Watanabe, Yoshiyuki; Wada, Yasuhiko; Inaba, Yutaka; Tamakoshi, Akiko
Abstract:
To examine sex-specific associations between sleep duration and mortality from cardiovascular disease and other causes.
Published:
2009
Title:
Associations between dietary patterns and semen quality in men undergoing IVF/ICSI treatment
Authors:
Vujkovic, M.; De Vries, J.H.; Dohle, G.R.; Bonsel, G.J.; Lindemans, J.; MacKlon, N.S.; Van Der Spek, P.J.; Steegers, E.A.P.; Steegers-Theunissen, R.P.M.
Abstract:
Background: This study investigates whether dietary patterns, substantiated by biomarkers, are associated with semen quality. Methods: In 161 men of subfertile couples undergoing in vitro fertilization treatment in a tertiary referral clinic in Rotterdam, the Netherlands, we assessed nutrient intakes and performed principal component factor analysis to identify dietary patterns. Total homocysteine (tHcy), folate, vitamin B12 and B6 were measured in blood and seminal plasma. Semen quality was assessed by sperm volume, concentration, motility, morphology and DNA fragmentation index (DFI). Linear regression models analyzed associations between dietary patterns, biomarkers and sperm parameters, adjusted for age, body mass index (BMI), smoking, vitamins and varicocele. Results: The 'Health Conscious' dietary pattern shows high intakes of fruits, vegetables, fish and whole grains. The 'Traditional Dutch' dietary pattern is characterized by high intakes of meat, potatoes and whole grains and low intakes of beverages and sweets. The 'Health Conscious' diet was inversely correlated with tHcy in blood (β = -0.07, P = 0.02) and seminal plasma (β = -1.34, P = 0.02) and positively with vitamin B6 in blood (β = 0.217, P = 0.01). An inverse association was demonstrated between the 'Health Conscious' diet and DFI (β = -2.81, P = 0.05). The 'Traditional Dutch' diet was positively correlated with red blood cell folate (β = 0.06, P = 0.04) and sperm concentration (β = 13.25, P = 0.01). Conclusions: The 'Health Conscious' and 'Traditional Dutch' dietary pattern seem to be associated with semen quality in men of subfertile couples.
Published:
2009
Title:
Autophagy Suppresses Tumorigenesis through Elimination of p62
Authors:
Mathew, Robin; Karp, Cristina M.; Beaudoin, Brian; Vuong, Nhan; Chen, Guanghua; Chen, Hsin Yi; Bray, Kevin; Reddy, Anupama; Bhanot, Gyan; Gelinas, Celine; DiPaola, Robert S.; Karantza-Wadsworth, Vassiliki; White, Eileen
Abstract:
Allelic loss of the essential autophagy gene beclin1 occurs in human cancers and renders mice tumor-prone suggesting that autophagy is a tumor-suppression mechanism. While tumor cells utilize autophagy to survive metabolic stress, autophagy also mitigates the resulting cellular damage that may limit tumorigenesis. In response to stress, autophagy-defective tumor cells preferentially accumulated p62/SQSTM1 (p62), endoplasmic reticulum (ER) chaperones, damaged mitochondria, reactive oxygen species (ROS), and genome damage. Moreover, suppressing ROS or p62 accumulation prevented damage resulting from autophagy defects indicating that failure to regulate p62 caused oxidative stress. Importantly, sustained p62 expression resulting from autophagy defects was sufficient to alter NF-κB regulation and gene expression and to promote tumorigenesis. Thus, defective autophagy is a mechanism for p62 upregulation commonly observed in human tumors that contributes directly to tumorigenesis likely by perturbing the signal transduction adaptor function of p62-controlling pathways critical for oncogenesis. © 2009 Elsevier Inc. All rights reserved.
Published:
2009
Title:
Background-Free Protein Detection in Polyacrylamide Gels and on Electroblots Using Transition Metal Chelate Stains
Authors:
Patton, Wayne F.
Abstract:
Electrophoretically separated proteins may be visualized using organic dyes such as Ponceau Red, Amido Black, Fast Green, or most commonly Coomassie Brilliant Blue (1,2). Alternatively, sensitive detection methods have been devi sed using metal ions and colloids of gold, silver, copper, carbon, or iron (3–12). Metal chelates form a third class of stains, consisting of transition metal complexes that bind avidly to proteins resolved in polyacrylamide gels or immobilized on solid-phase membrane supports (13–27). In recent years, metal chelate stains have been designed and optimized specifically for compatibility with commonly used microchemical characterization procedures employed in proteomics. The metal chelate stains are simple to implement, and do not contain extraneous chemicals such as glutaraldehyde, formaldehyde, or Tween-20 that are well known to interfere with many downstream protein characterization procedures.Metal chelates can be used to detect proteins on nitrocellulose, poly(vinylidene difluoride) (PVDF), and nylon membranes as well as in polyacrylamide and agarose gels. The metal complexes do not modify proteins, and are compatible with immunoblotting, lectin blotting, mass spec-trometry, and Edman-based protein sequencing (13–17,22–27). Metal chelate stains are suitable for routine protein measurement in solid-phase assays owing to the quantitative stoichiometry of complex formation with proteins and peptides (15,16). Such solid phase protein assays are more sensitive and resistant to chemical interference than their solution-based counterparts (15).
Published:
2009
Title:
Biogeochemical Evidence for the Environments of Early Homo in South Africa
Authors:
Sponheimer, Matt; Lee-Thorp, Julia A.
Abstract:
It has long been observed that early members of the genus Homo are associated with more open and arid-adapted fauna than antecedent australopith species (e.g., Vrba, 1980; Wesselman, 1985; Reed, 1997; Bobe and Behrensmeyer, 2004). Moreover, the fi rst appearances of earliest Homo (̃2.5 Ma; Hill et al., 1992; Schrenk et al., 1993; Kimbel et al., 1996) and Homo ergaster (̃1.8 Ma; Feibel et al., 1989) are broadly coincident with a series of global climate changes that included the onset of northern hemisphere glaciation and the Walker circulation respectively (Trauth et al., 2005). Together, these observations suggest the possibility of some linkage between the origin and subsequent speciation of Homo and climatic/environmental change; yet, there are several reasons to be cautious about accepting this linkage at face value. For one, large-scale climate processes are not discrete “events,” and thus are very diffi cult to tie to specifi c speciation and/or extinction events in the fragmentary, and often chronologically ambiguous, terrestrial fossil record. For another, the paleoclimatic data that are often used to posit such linkages are usually global in nature (e.g., Prentice and Denton, 1988; deMenocal, 1995), and thus their relevance for animals in particular basins and around specifi c sites is unclear. This is particularly problematic with respect to southern Africa, where climate change may be anti-phased or at least partially decoupled with respect to the better-known East African record (e.g., Partridge et al., 2004). In addition, paleoanthropologists working in southern Africa have fewer proxies with which to explore paleoclimate and environmental trends. For instance, the absence of pedogenic carbonates (from relevant ages and places), which have been used to investigate long-term environmental change (e.g., Cerling, 1992; Quade and Cerling, 1995; Wynn, 2004) and document vegetational diversity across paleolandscapes (Sikes, 1994), has made it diffi cult to cross-check both regional and local paleoenvironmental reconstructions in southern Africa. Thus, researchers in southern Africa have relied perforce upon global or regional datasets that may or may not be relevant, or have relied on the taxonomic or morphological character of hominin-associated fauna.
Published:
2009
Title:
Biomarkers in nutritional epidemiology: Applications, needs and new horizons
Authors:
Jenab, M.; Slimani, N.; Bictash, M.; Ferrari, P.; Bingham, S.A.
Abstract:
Modern epidemiology suggests a potential interactive association between diet, lifestyle, genetics and the risk of many chronic diseases. As such, many epidemiologic studies attempt to consider assessment of dietary intake alongside genetic measures and other variables of interest. However, given the multi-factorial complexities of dietary exposures, all dietary intake assessment methods are associated with measurement errors which affect dietary estimates and may obscure disease risk associations. For this reason, dietary biomarkers measured in biological specimens are being increasingly used as additional or substitute estimates of dietary intake and nutrient status. Genetic variation may influence dietary intake and nutrient metabolism and may affect the utility of a dietary biomarker to properly reflect dietary exposures. Although there are many functional dietary biomarkers that, if utilized appropriately, can be very informative, a better understanding of the interactions between diet and genes as potentially determining factors in the validity, application and interpretation of dietary biomarkers is necessary. It is the aim of this review to highlight how some important biomarkers are being applied in nutrition epidemiology and to address some associated questions and limitations. This review also emphasizes the need to identify new dietary biomarkers and highlights the emerging field of nutritional metabonomics as an analytical method to assess metabolic profiles as measures of dietary exposures and indicators of dietary patterns, dietary changes or effectiveness of dietary interventions. The review will also touch upon new statistical methodologies for the combination of dietary questionnaire and biomarker data for disease risk assessment. It is clear that dietary biomarkers require much further research in order to be better applied and interpreted. Future priorities should be to integrate high quality dietary intake information, measurements of dietary biomarkers, metabolic profiles of specific dietary patterns, genetics and novel statistical methodology in order to provide important new insights into gene-diet-lifestyle-disease risk associations. © Springer-Verlag 2009.
Published:
2009
Title:
Brains, Brawn, and the Evolution of Human Endurance Running Capabilities
Authors:
Lieberman, Daniel E.; Bramble, Dennis M.; Raichlen, David A.; Shea, John J.
Abstract:
Theories about hominin evolution are often connected intimately with notions of what it is to be human. Such ideas have had a particularly strong infl uence on thinking about the defi nition and origin of the human genus (see Landau, 1993; Wood and Collard, 1999; Wood, 2009). Many, if not most scenarios for the evolution of the genus Homo emphasize the importance of quintessentially human traits such as large brains, tool-making, and complex cognition. Usually these derived features have been interpreted, explicitly or implicitly, as a suite of novel strategies that emphasize cognitive over athletic means of competing with the rest of nature (“red in tooth and claw”). Most animals compete with each other to a signifi cant extent using athletic capabilities such as strength, power, agility and speed. Obviously, humans compare poorly with other mammals, including African apes, in these characteristics: we are weak, slow, and awkward creatures. Even though male chimpanzees weigh less than a typical adult modern human, they can produce much more force, can sprint more rapidly, and are obviously more agile during locomotion (Stedman et al., 2004). Yet, although no human alive could match a chimpanzee in hand-to-hand combat, our cognitive capacities are extraordinarily better developed. Accordingly, it seems reasonable to focus on evolutionary scenarios for the genus Homo that explain the triumph of brains over brawn.Interestingly, the idea that humans are poor athletes is demonstrably wrong in one crucial respect. While humans have comparatively poor performance capabilities in terms of power and strength, we are unusually specialized endurance athletes, with surprisingly impressive aerobic performance capabilities. These capabilities are particularly remarkable for endurance running (ER), defi ned as running long-distances (>5 km) using aerobic metabolism. These capabilities, which have been reviewed in depth by Carrier (1984) and Bramble and Lieberman (2004), compare extremely well to other mammals, especially primates, in terms of several performance criteria such as speed and distance, especially in hot conditions.
Published:
2009
Title:
Carolus Linnaeus (1707-1778): His Life, Philosophy and Science and Its Relationship to Modern Biology and Medicine
Authors:
Reid, Gordon McGregor
Abstract:
The system of binomial nomenclature and wider taxonomic paradigm forged by Carolus Linnaeus in the 18th century came from his original approach to understanding the natural world. It was also a product of environmental, economic, social, cultural, political and theological influences of the time. For Linnaeus the identification, naming and classification of different kinds of animals, plants, diseases, fossils and rocks had practical as well as theoretical importance. In his life and work he clearly demonstrates the 'scientific approach' including careful information gathering, exploration, empiricism, dissection, accurate observations and published descriptions. There is an inspirational use of morphological characters in comparative diagnoses, a requirement for material evidence to support hypotheses and the systematic and hierarchical organisation of knowledge. However, techniques for specimen preservation and analysis were limited and sample sizes too small to properly characterise wild populations. Thus he bequeathed artificial and 'typological' more than biological concepts determined by form and pattern rather than process. Species and genera were regarded as fixed, objective entities. This is sometimes associated with the supposedly stultifying effects of Aristotelian essentialism on Linnaean and later taxonomy. 'Natural' classification, as far as developed, was not phyletic but, instead, reflected Wolffianism, a modified creationist doctrine. Nonetheless, Linnaeus was the first to formally recognise the close affinity between humans and primates, a controversial idea later fully developed by Charles Darwin. Even so, Linnaeus did not always distinguish between mythological versus real creatures and incredible versus credible hypotheses. His understanding of 'cause and effect' was circumscribed by prevailing Lutheran theology and Cartesian mechanistic philosophy. Linnaeus was as much a working physician, agriculturalist and land surveyor as he was a taxonomist. Contemporary economic biology and biotechnology are anticipated in his animal and plant breeding and pearl culturing experiments. In the great body of Linnaeus' letters, manuscripts and books are discernable foundations for many other later disciplines. These include: anthropology, biogeography, bioinformatics, biomechanics, biological control, conservation, ecology, epidemiology, Darwinian evolution, ethnography, medical diagnostics, microbiology, palaeontology, pharmacology and phylogenetic systematics.
Published:
2009
Title:
Casting Immobilized pH Gradients
Authors:
Gianazza, Elisabetta
Abstract:
One of the main requirements for a 2-D protocol is reproducibility of spot position, and, indeed, the technique of isoelectric focusing on immobilized pH gradients (IPGs) is ideally suited to provide highly reproducible 1-d separations. IPGs are obtained through the copolymerization of acidic and basic acrylamido derivatives of different pKs within a polyacrylamide matrix (1, 2) (Fig. 1). The pH gradient may be devised by computer modeling either with a linear or with an exponential course. IPGs are cast from two limiting solutions containing the buffering chemicals at concentrations adjusted to give the required pH course upon linear mixing. For consistent results, gradient pouring and polymerization are carried out under controlled conditions. The covalent nature of the chemical bonds formed during the polymerization step results in a permanent stability of the pH gradient within the matrix. Conflicting requirements during the focusing procedure prevent any effective use of IPGs into capillary tubes (3): The need to buffer with carrier ampholytes (CAs) the pH extremes caused by the migration of the polymerization catalysts is contrasted by the adverse effects of the electroendosmotic flow brought about by the addition of CAs to the gel phase. The demand for the IPG gels to be backed by a binding support—they are usually cast on GelBond™ foils—results in dimensional stability between 1-D and 2-D as a further assistance to reproducibility.
Published:
2009
Title:
Cetyltrimethylammonium Bromide Discontinuous Gel Electrophoresis of Proteins
Authors:
Akins, Robert E.; Tuan, Rocky S.
Abstract:
This chapter describes a novel method of electrophoresis that allows the fine separation of proteins to be carried out with the retention of native activity. The system combines discontinuous gel electrophoresis in an arginine/N-Tris (hydroxymethyl methylglycine) (Tricine) buffer with sample solubilization in cetyltrimethylammonium bromide (CTAB). Because the components that distinguish this system are CTAB, arginine, and Tricine and because CTAB is a cationic detergent, we refer to this method as CAT gel electrophoresis (1, 2). Proteins separated on CAT gels appear as discrete bands, and their mobility is a logarithmic function of M r across a broad range of molecular weights. After CAT electrophoresis, many proteins retain high enough levels of native activity to be detected, and gel bands may be detected by both M r and protein-specific activities. In this chapter, we provide a description of the procedures for preparing and running CAT gels. We also provide some technical background information on the basic principles of CAT gel operation and some points to keep in mind when considering the CAT system.
Published:
2009
Title:
Chemical pathology of homocysteine. IV. Excitotoxicity, oxidative stress, endothelial dysfunction, and inflammation
Authors:
McCully, Kilmer S.
Abstract:
This review considers recent advances in the chemical pathology of homocysteine in atherogenesis, oxidative metabolism, and carcinogenesis. Homocysteine is a potent excitatory neurotransmitter that binds to the N-methyl-D-aspartate (NMDA) receptor and leads to oxidative stress, cytoplasmic calcium influx, cellular apoptosis, and endothelial dysfunction. According to the adsorption-induction theory, cytoplasmic calcium influx leads to depletion of cellular adenosine triphosphate (ATP) by reaction with cytoplasmic phosphate, leading to calcium apatite deposition. Oxidative stress is caused by failure of ATP synthesis and accumulation of reactive oxygen radicals, theoretically because of inhibition of thioretinaco ozonide function within mitochondria and endoplasmic reticulum. The toxicity of oxygen difluoride is theoretically explained by the displacement of ozone from thioretinaco ozonide, leading to inhibition of cellular respiration. Depletion of thioretinaco ozonide from cellular membranes is suggested to underlie the carcinogenic and atherogenic effects of fluoride and other electrophilic carcinogens. In atherogenesis the acute inflammatory response is related to cellular apoptosis and necrosis, autoantibodies to proteins containing peptide-bound homocysteine and oxidized low-density lipoprotein (Ox-LDL), and microbial products and antigens originating from homocysteinylated LDL aggregates trapped within vasa vasorum of developing atherosclerotic plaques. The trapping of lipoprotein aggregates and obstruction of the lumen of vasa vasorum are enhanced by high tissue pressure and by endothelial dysfunction because of narrowing of the lumen by swollen and hyperplastic endothelial cells, leading to the creation of vulnerable plaques.
Published:
2009
Title:
Comparing 2D Electrophoretic Gels Across Internet Databases: An Open Source Application
Authors:
Lemkin, Peter F.; Thornwall, Gregory C.; Evans, Jai A.
Abstract:
Published:
2009
Title:
Comparisons of Early Pleistocene Skulls from East Africa and the Georgian Caucasus: Evidence Bearing on the Origin and Systematics of Genus Homo
Authors:
Rightmire, G. Philip; Lordkipanidze, David
Abstract:
A half century ago, when there were fewer fossils (and not so many paleoanthropologists), characterizing the genus Homo was relatively straightforward. In addition to modern humans, Neanderthals could be included, along with other archaics such as Broken Hill (now Kabwe) from Zambia and the Ngandong assemblage from Java. Also, it was becoming clear that Atlanthropus from northern Africa, and Pithecanthropus and Sinanthropus from eastern Asia, should be lumped into this same taxon. Phillip Tobias (2009) has noted that the situation changed rather dramatically in 1964, with the naming of Homo habilis. Accommodating the newly discovered Olduvai remains in Homo required expanding the existing defi nition of the genus. This trend has continued.Along with the traditional emphasis on morphology of skulls, teeth, and postcranial bones, investigators have added criteria relating to energetics and diet, tool-making, and the ability to communicate using spoken language. Recently, issues of life history and the timing of development have been raised as well. Bernard Wood (2009) has reminded us that some of these characters help in exploring phylogeny (Homo as a clade) and others assist in assessing the grade status of individual species.
Published:
2009
Title:
Consequences of a plant-based diet with low dairy consumption on intake of bone-relevant nutrients
Authors:
Merrill, R.M.; Aldana, S.G.
Abstract:
Objective: This study examines the extent to which a plant-based dietary intervention that discourages consumption of dairy products and meat influences bone-relevant nutrients. Methods: A randomized controlled study design was used to evaluate the Coronary Health Improvement Project. The Project is a heart disease prevention intervention administered in an intensive 40-hour educational course delivered over a 4-week period. Participants were evaluated at baseline, 6 weeks, and 6 months. Results: After 6 weeks, participants in the intervention group compared with the control group experienced significant increases in magnesium and daily intake of fruit, vegetables, and grains but significant decreases in dairy servings per day and calcium and vitamin D from food. After 6 months, those in the intervention group showed significant increases in daily intake of fruit, vegetables, and grains and significant decreases in dairy servings per day, daily meat consumption, and protein, phosphorous, calcium, total calcium, and vitamin D from food. Serum calcium levels are the primary determinant of parathyroid hormone (PTH) release, and within 6 weeks, the intervention group's PTH levels were elevated from baseline and significantly different from the control group's PTH levels. At 6 months, urinary type I collagen N-telopeptide (NTx) levels were significantly greater in the intervention group compared with the control group. Conclusions: The Coronary Health Improvement Project increases the intake of important food items but decreases calcium and vitamin D consumption. There is also some evidence of an increase in NTx biomarkers, consistent with increased bone resorption. ©2009, Mary Ann Liebert, Inc.
Published:
2009
Title:
Continuous relationships between non-diabetic hyperglycaemia and both cardiovascular disease and all-cause mortality: The Australian Diabetes, Obesity, and Lifestyle (AusDiab) study
Authors:
Barr, E. L M; Boyko, E. J.; Zimmet, P. Z.; Wolfe, R.; Tonkin, A. M.; Shaw, J. E.
Abstract:
AIMS/HYPOTHESIS: Hyperglycaemia is a risk factor for cardiovascular disease (CVD) and all-cause mortality in individuals without diabetes. We investigated: (1) whether the risk of all-cause and CVD mortality extended continuously throughout the range of fasting plasma glucose (FPG), 2 h plasma glucose (2hPG) and HbA(1c) values; and (2) the ability of these measures to improve risk prediction for mortality.$\backslash$n$\backslash$nMETHODS: Data on 10,026 people aged \textgreateror=25 years without diagnosed diabetes were obtained from the population-based Australian Diabetes, Obesity and Lifestyle study. Between 1999 and 2000, FPG, 2hPG and HbA(1c) were assessed and all-cause (332 deaths) and CVD (88 deaths) mortality were obtained after 7 years.$\backslash$n$\backslash$nRESULTS: Both 2hPG and HbA(1c) exhibited linear relationships with all-cause and CVD mortality, whereas FPG showed J-shaped relationships. The adjusted HR (95% CI) for all-cause mortality per SD increase was 1.2 (1.1-1.3) for 2hPG and 1.1 (1.0-1.2) for HbA(1c). The HR for FPG \textless5.1 mmol/l (per SD decrease) was 2.0 (1.3-3.0); for FPG \textgreateror=5.1 mmol/l (per SD increase) the HR was 1.1 (1.0-1.2). Corresponding HRs for CVD mortality were 1.2 (1.0-1.4), 1.2 (1.0-1.3), 4.0 (2.1-7.6) and 1.3 (1.1-1.4). The discriminative ability of each measure was similar; no measure substantially improved individual risk identification over traditional risk factors.$\backslash$n$\backslash$nCONCLUSIONS/INTERPRETATION: In individuals without diagnosed diabetes, 2hPG and FPG, but not HbA(1c) were significant predictors of all-cause mortality, whereas all measures were significant predictors of CVD mortality. However, these glucose measures did not substantially improve individual risk identification.
Published:
2009
Title:
Cooking and the human commitment to a high-quality diet
Authors:
Carmody, R. N.; Wrangham, R. W.
Abstract:
For our body size, humans exhibit higher energy use yet reduced structures for mastication and digestion of food compared to chimpanzees, our closest living relatives. This suite of features suggests that humans are adapted to a high-quality diet. Although increased consumption of meat during human evolution certainly contributed to dietary quality, meat-eating alone appears to be insufficient to support the evolution of these traits, because modern humans fare poorly on raw diets that include meat. Here, we suggest that cooking confers physical and chemical benefits to food that are consistent with observed human dietary adaptations. We review evidence showing that cooking facilitates mastication, increases digestibility, and otherwise improves the net energy value of plant and animal foods regularly consumed by humans. We also address the likelihood that cooking was adopted more than 250,000 years ago (kya), a period that we believe is sufficient in length for the proposed adaptations to have occurred. Additional experimental work is needed to help discriminate the relative contributions of cooking, meat eating, and other innovations such as nonthermal food processing in supporting the human transition toward dietary quality.
Published:
2009
Title:
Dental Evidence for Diets of Early Homo
Authors:
Ungar, Peter S.; Scott, Robert S.
Abstract:
The evolution of diet in the earliest members of our genus, Homo rudolfensis, H. habilis and H. erectus has received increased attention over the past few years (see Ungar et al., 2006a for review). Many models have been constructed, based largely on nutritional studies combined with direct analogy (with living peoples or non-human primates) or on contextual evidence, such as archeological and paleoenvi-ronmental indicators. These models suggest hypotheses, some of which can be tested with the fossil evidence for the hominins themselves.In this paper we review and evaluate some recent models for the dietary adaptations of early Homo. While there are real intractable limits to what we can learn, the dental remains of these hominins offer some clues to the diets of these species. Results of a recent study on molar occlusal functional morphology (Ungar, 2004) will be reviewed, along with results from a recent study of dental microwear of early Homo (Ungar et al., 2006b). In addition, new data on dental microwear textures for early Homo cheek teeth will be presented for comparison with results for extant primates and other fossil hominins.
Published:
2009
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