Rich Carbohydrate Research Articles

Effect of Implementing Dental Services in Israeli Psychiatric Hospitals on the Oral and Dental Health of Inpatients

Effect of Implementing Dental Services in Israeli Psychiatric Hospitals on the Oral and Dental Health of Inpatients

BATS ABSORB NUTRIENTS LIKE A BIRD

If you've ever had to pay excess baggage on an aircraft, you've probably thought about the costs of flight when carrying additional loads. Another flying mammal, the bat, faces the same problem and seems to get round this problem by having less intestinal tissue than comparably sized but non-flying mammals. With this refinement bats manage to reduce the mass of material carried by the gut to improve their take-off and manoeuvrability during flapping flight. However, small bats have very high energy demands when flying and thus need to extract energy efficiently from food at high rates, despite their smaller intestines. So how do flying mammals like bats efficiently absorb energy rich carbohydrates, given their smaller intestinal surface area and high energy demands? Birds meet their high energy demands by absorbing nutrients by passive diffusion across the gut lumen into the blood(paracellular uptake). However, transporter proteins actively transport solutes across the gut lumen, via the transcellular uptake mechanism,in mammals. So is nutrient uptake in the bat's digestive system more bird like or mammal like?To answer this question, Enrique Caviedes-Vidal from Argentina and his international team of colleagues measured intestinal carbohydrate uptake in the great fruit-eating bat (Artibeus literatus). First they fed the bats, and then they injected the animals intraperitoneally with two metabolically inert, water soluble carbohydrates (l-rhamnose and cellobiose) and compared the carbohydrate concentrations in the blood plasma over 3 h after intake. As the molecular weight of cellobiose is twice that of l-rhamnose, l-rhamnose will pass into the bird's bloodstream faster than cellobiose if the uptake mechanism is paracellular,while the two carbohydrates will be absorbed at the same rate if uptake is mediated by transcellular uptake.The researchers found that intestinal uptake of l-rhamnose was much higher than the absorption of the large disaccharide cellobiose. And when the team repeated experiments with another carbohydrate,3-O-methyl-d-glucose, which is both actively and passively transported, they found out that even 3-O-methyl-d-glucose was predominantly absorbed by the paracellular pathway. The bats absorb nutrients via passive paracellular uptake. When comparing the bats'absorption rates with the data previously measured in other mammals, it turned out that passive absorption is significantly higher in great fruit-eating bats than in non-flying mammals and can amount to 70% of total glucose absorption. The observed uptake rates in the bats were more similar to those of birds,rather than mammals, and thus the authors conclude that paracellular absorption by passive diffusion may serve small bats as well as birds to compensate for their relatively small intestinal surface area.The team also propose several mechanisms that might account for high passive carbohydrate absorption including increased microvilli surface areas and more cell junctions, a higher pore radius to facilitate the sieving effect and an increase in water flux to elevated the carriage of solute across the junctions.Together, the study on intestinal absorption in the great fruit-eating bat provides evidence that small flying bats and birds compensate for their relatively small guts and reduce the surface area for absorption with paracellular carbohydrate absorption. However, the team point out that there are risks associated with paracellular absorption. High intestinal permeability might permit toxins to be absorbed in the intestinal lumen,leaving bats vulnerable to toxins that other mammals would not fall prey to.

INFLUÊNCIA DA INGESTÃO DE CARBOIDRATOS SOBRE O DESEMPENHO FÍSICO

Beyond maintaining glycemic homeostasis, rich carbohydrate diets provide a larger muscle and hepatic glycogen storage. Higher muscle glycogen stores propitiate a higher level of energy to the organism and often help to delay the beginning of the muscle fatigue. In moderate efforts made at long intervals of time or in short-term physical exercises of high intensity muscle glycogen stores are strongly depleted, leading to a fall in performance and even to hypoglycemia and dehydration. Thus the aim of this study was to analyze the influence of carbohydrates ingestion before, during and after physical exercise for performance improvement.

Dietas hiperglicídicas: efeitos da substituição isoenergética de gordura por carboidratos sobre o metabolismo de lipídios, adiposidade corporal e sua associação com atividade física e com o risco de doença cardiovascular

For many years the reduction in the dietary fat has been recommended to the population, in order to prevent cardiovascular diseases, obesity, type 2 diabetes mellitus, among other chronic diseases. The consequence has been the replacement of carbohydrates by fat, resulting in the adoption of high carbohydrate diets. However, it has been still discussed if very rich carbohydrate diets should be recommended to the general population. Researches point out controversies about the association between these dietary habits and harmful effects on health and metabolic aspects, such as raise in de novo lipogenesis and triglyceride concentration, reduction in HDL concentration and effects on adiposity. This review evaluates the effects of diet modification, particularly the high-carbohydrate diet, in cardiovascular risk factors such as dyslipidemia and obesity. It also reviews its interaction with physical activity since it is still unknown with which extension it can minimize possible harmful effects of high carbohydrate diets in the long term.

Regulation of Cardiac Energy Metabolism in Newborn

Energy in the form of ATP is supplied from the oxidation of fatty acids and glucose in the adult heart in most species. In the fetal heart, carbohydrates, primarily glucose and lactate, are the preferred sources for ATP production. As the newborn matures the contribution of fatty acid oxidation to overall energy production increases and becomes the dominant substrate for the adult heart. The mechanisms responsible for this switch in energy substrate preference in the heart are complicated to identify due to slight differences between species and differences in techniques that are utilized. Nevertheless, our current knowledge suggests that the switch in energy substrate preference occurs due to a combination of events. During pregnancy, the fetus receives a constant supply of nutrients that is rich carbohydrates and poor in fatty acids in many species. Immediately after birth, the newborn is fed with milk that is high in fat and low in carbohydrates. The hormonal environment is also different between the fetal and the newborn. Moreover, direct subcellular changes occur in the newborn period that play a major role in the adaptation of the newborn heart to extrauterin life. The newborn period is unique and provides a very useful model to examine not only the metabolic changes, but also the effects of hormonal changes on the heart. A better understanding of developmental physiology and metabolism is also very important to approach certain disorders in energy substrate metabolism.

Influence de la nutrition sur le sommeil et la vigilance

Numerous data suggest that food intake is able to influence sleep and wakefulness. The knowledge on the sleep physiology allows to formulate several hypothesis on the mechanisms involved in the relationship between diet and sleep. It has been observed that enhanced food intake increases sleep duration whereas a reduced food supply decreases sleep duration. Moreover, the nature of nutriment is able to influence wakefulness. A rich carbohydrate meal can decrease vigilance in a subject submitted to sleep deprivation whereas a protein diet can improve psychocognitive performances in such a situation. The physiological mechanisms suggested to explain the role of volume and nature of a meal are related with the role of nutriment on neuromediators metabolism or the hormonal changes induced by the feeding pattern. From a practical point of view the knowledge of the diet impact on sleep and wakefulness may be useful in the management of healthy subject and also of consequencies of metabolic diseases.

Combined Effects of Rich Carbohydrate Diets and Endurance Exercise on Glycogen Metabolism in Rat Liver and Skeletal Muscle

Combined Effects of Rich Carbohydrate Diets and Endurance Exercise on Glycogen Metabolism in Rat Liver and Skeletal Muscle

Biochemical definition of human tracheobronchial mucus.

Tracheobronchial mucus is a heterogeneous milieu produced by several cell types. It has viscoelastic properties related to the organization of macromolecular components such as glycoproteins, proteins, lipids and nucleic acids. Proteins comprise components antigenically related to plasma proteins and secretory proteins such as kallicrein, lysozyme, amylase, bronchotransferrin, immunoglobulins A and proline-rich polypeptides. Tracheobronchial mucus also contains protease inhibitors and, in pathological conditions, important amounts of protease. Mucins, which are glycoproteins with a very rich carbohydrate content, represent another complex and major group of tracheobronchial molecules.

Purification of kallikrein from cat submaxillary gland.

Cat submaxillary kallikrein was purified from the water extract of the gland by 50-75% acetone fractionation, DEAE-Sephadex A-50 chromatography, Sephadex G-75 gel filtration and Ampholine isoelectric focusing. The final preparation gave the activities of 1260 KU/mg in vasodilator assay, 24.5 and 11.6 units/mg on BAEE and TAME esterolytic assay, respectively. Trasylol gave only weak inhibitory effect on this kallikrein. The isoelectric points of the kallikrein were in the range pH 4.2-5.0, and this kallikrein seemed to consist of several multiple forms with different pI values, like some other glandular kallikreins. It gave a single protein band in disc electrophoresis, while it migrated in retard and formed a broad one. This may be ascribable to the rich carbohydrate content in the kallikrein.

AN UNUSUAL EFFECT OF A CARBOHYDRATE-RICH, FAT-POOR DIABETIC DIET. REPORT OF A CASE.

Ever since the days of von Noorden’s famous oatmeal cure, the tendency in diabetic diets has been toward greater liberty with carbohydrate-containing food. The beneficial effect of the oatmeal cure and that of its many modifications was variously ascribed to the low protein, the mineral, and the carbohydrate content. After its initial success, interest lagged in rich carbohydrate days until after the discovery of insulin. Sansum (2) in California and Adlersberg and Porges (1) in Vienna independently revived interest in the possibility of allowing diabetic patients increased amounts of carbohydrate-containing foods. When the carbohydrates were increased, the total calories were maintained constant by a corresponding reduction in the fats. Whether the beneficial clinical results which have been obtained by using these diets are due to the increase in the carbohydrates or to the decrease in the fats is still debatable.