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Acinar cells -- Exocrine pancreatic cells. Epithelial secretory cells arranged as a ball of cells around the lumen of a gland (as in the pancreas). Cells of the pancreas that secrete digestive enzymes.

Active transport -- the carriage of a solute across a biological membrane from low to high concentration that requires the expenditure of (metabolic) energy.

Advanced Glycation End-products (AGEs) -- Glycation is considered a major pathophysiological mechanism causing tissue damage in diabetic subjects. Glycation involves the reaction of glucose and/or other reducing sugars with amino groups in proteins, resulting in the formation of a Schiff base or aldimine. This labile adduct can tautomerize via the Amadori rearrangement to the more stable ketoamine. The function of a glycated protein may be impaired if an amino group affected by glycation is in, or close to, its active site. For example, glycation of the chains of hemoglobin gives rise to the glycated hemoglobins (HbA1), in which responsiveness to 2,3-diphosphoglycerate is decreased and oxygen affinity increased. (See HbA1/c)

Agonist -- an endogenous substance or a drug that can interact with a receptor and initiate a physiological or a pharmacological response characteristic of that receptor (contraction, relaxation, secretion, enzyme activation, etc.).

Allosteric binding sites -- contained in many enzymes and receptors. As a consequence of the binding to Allosteric binding sites, the interaction with the normal ligand may be either enhanced or reduced.

Analog -- a drug whose structure is related to that of another drug but whose chemical and biological properties may be quite different.

Antagonist -- a drug or a compound that opposes the physiological effects of another. At the receptor level, it is a chemical entity that opposes the receptor-associated responses normally induced by another bioactive agent.

Antioxidants -- Chemicals that react with and neutralize the free radicals that would otherwise lead to cellular damage and off flavors, odors, tastes and appearances in food products. Antioxidants can help prevent cancer and heart disease and oxidation and rancidity in food. Common natural antioxidants include vitamins C and E and beta-carotene.

Alpha cell -- a type of cell in the pancreas. Alpha cells make and release a hormone called glucagon. The body sends a signal to the alpha cells to make glucagon when blood glucose falls too low. Then glucagon reaches the liver where it tells it to release glucose into the blood for energy.

Amino acid -- unit molecule from which proteins are constructed by polymerization.

Amylase -- The enzyme found selectively in the exocrine pancreas.

Amylin -- a hormone formed by beta cells in the pancreas. Amylin regulates the timing of glucose release into the bloodstream after eating by slowing the emptying of the stomach. Natural hormone produced by pancreatic beta-cells that moderates the glucose-lowering effects of insulin. One of the calcitonin family peptides.

Anabolism -- Synthesis; opposite of catabolism. The phase of intermediary metabolism concerned with the energy-requiring biosynthesis of cell components from smaller precursor molecules.

Adenosine triphosphate (ATP) -- A relatively stable, high energy molecule used to fuel chemical reactions within cells.

Antisense primers -- Relate to particular mRNA types. Expressed similarto the following: Primer sets ... IPF-1 primers (product size 262 bp)5-CCCATGGATGAAGTCTACC-3 and 5-GTCCTCCTCCTTTTTCCAC-3, ... In general the complementary strand of a coding sequence of DNA or of mRNA. Antisense RNA hybridizes with and inactivates mRNA.(Also see sense primers and base.)

Apoptosis or active (programmed) cell death -- The most common form of physiological (as opposed to pathological) cell death. Apoptosis is an active process requiring metabolic activity by the dying cell; often characterized by shrinkage of the cell, cleavage of the DNA into fragments that give a so-called "laddering pattern" on gels and by condensation and margination of chromatin. Often called programmed cell death, though this is not strictly accurate. Cells that die by apoptosis do not usually elicit the inflammatory responses that are associated with necrosis, though the reasons are not clear.(ACD/PCD) Source:1 Go to "Site Map" or search. Enter "Apoptosis". You will see some of the terms used elsewhere in this glossary such as Bcl-2. See the above site for links or references to the following: Apoptosis MiniCOPE Dictionary Apoptosis I Apoptosis II Apoptosis from Kimball's Biology Pages Apoptosis glossary Apoptosis Online Arrestins as signaling molecules involved in apoptotic pathways List of apoptosis regulators Mitochondrial control of apoptosis in ageing and exercise Molecular events regulating active cell death The Virtual Library - Apoptosis

Arachidonic Acid (AA) -- A long chain omega-6 fatty acid that contains 20 carbon atoms and four unsaturations (C20:4n-6). It is found prominently in animal products. AA is the principal precursor to series 2 eicosanoids which cause constriction of blood vessels and quicken blood clotting.

Arteriosclerosis -- Diseases characterized by thickening and loss of the elasticity of arterial walls.

Atherosclerosis -- A common form of arteriosclerosis in which deposits of yellowish plaque containing cholesterol and other lipids are formed within the walls of the arteries. This condition can cause hardening of the arteries, mainly that of the heart, brain and legs causing heart attacks, angina pains, strokes and poor blood circulation.

Axis -- For medical purposes, an axis is a interaction between one organ an another, one hormone and another. It is considered a relationship of communication. Some of these relationships involve feedback.

Base (nucleotide) -- A segment of the DNA (and RNA) molecules--- one of the four (repeating) chemical units that comprise DNA/RNA that, according to their order and pairing (i.e., on the parallel strands of DNA/RNA molecules), represent the different amino acids (i.e., within the protein molecule that each gene in the DNA codes-for). The four bases that comprise DNA are adenine (A), cytosine (C), guanine (G), and thymine (T). (See nucleotide.)

Bcl-2 Family -- Proto-oncogene, activated by chromosome translocation in human B-cell lymphomas (hence "bcl"). Encodes a plasma membrane protein. The gene product inhibits programmed cell death (apoptosis). Bcl-2 (I), Bcl-Xl (I), Bcl-Xs (P), Bax (P), Bad (P), Bag (I), Bak (P), Bid (I)-- in the panceras some are in the endocrine, some are in the exocrine, and some are in both. In the islets some are limited to alpha cells, some to beta, and some to other islet cell types. (I) indicates inhibits cell death by apoptosis and (P) indicates promotes cell death by apoptosis.

Beta cell -- a cell that makes insulin. Beta cells are located in the islets of the pancreas.

Biochemistry -- the study of those molecules used and manufactured by living things.

Blood glucose -- the main sugar found in the blood and the body's main source of energy. Also called blood sugar.

Blood urea nitrogen (BUN)-- a waste product in the blood from the breakdown of protein. The kidneys filter blood to remove urea. As kidney function decreases, the BUN levels increase.

Carbohydrate -- one of the three main nutrients in food. Foods that provide carbohydrate are starches, vegetables, fruits, dairy products, and sugars.

Cardiovascular system -- Pertaining to heart and blood vessels.

Caspases --An enzyme in a family of cysteine proteases (i.e. Cys in the active site) that cleave +H3N- ... -Asp-Xaa- ...-COO- bond. 2 Go to "Site Map" or search. Enter "caspases."

Catabolism -- consists of reactions involving endogenous organic substrates to provide chemically available energy (e.g., ATP) and/or to generate metabolic intermediates used in subsequent anabolic reactions.

Cell -- Fundamental structural unit of all life. The cell consists primarily of an outer plasma membrane, which separates it from the environment; the genetic material (DNA), which encodes heritable information for the maintainance of life; and the cytoplasm, a heterogeneous assemblage of ions, molecules, and fluid.

Cell components -- Plasma (cell) membrane, cytoplasm, nucleus, cytoskeleton, and cellular organelles (mitochondria, ribosomes, endoplasmic reticlulum, and golgi complex.)

Cell cycle -- Complete sequence of steps which must be performed by a cell in order to replicate itself, as seen from mitotic event to mitotic event. Most of the cycle consists of a growth period in which the cell takes on mass and replicates its DNA. Arrest of the cell cycle is an important feature in the reproduction of many organisms, including humans. The sequence of events between mitotic divisions. The cycle is conventionally divided into G0, G1, (G standing for gap), S (synthesis phase during which the DNA is replicated), G2 and M (mitosis). Cells that will not divide again are considered to be in G0, and the transition from G0 to G1 is thought to commit the cell to completing the cycle and dividing.

Cell membrane -- The outer membrane of a cell, which separates it from the environment. Also called a plasma membrane or plasmalemma.

Cell membrane transport -- The facilitated transport of a solute across a membrane, usually by a specific membrane protein (e.g., adhesion molecule, receptor, etc.). Also see Link Go to "Site Map" or search. Enter "cell membrane transport."

Cholesterol -- a type of fat (lipid) produced by the liver and found in the blood; it is also found in some foods. Cholesterol is used by the body to make steroid hormones and build cell membranes. It is a precursor to bile acids. Elevated serum cholesterol levels can lead to heart disease (atherosclerosis) by promoting plaque deposition in the arteries. Serum cholesterol levels are controlled in some by one's genetic makeup and in others by the amount of saturated fat and cholesterol in the diet.

Chronic -- describes something that is long-lasting. Opposite of acute.

Clone -- a population of genetically identical cells produced from a common ancestor. Sometimes, "clone" is also used for a number of recombinant DNA (deoxyribonucleic acid) molecules all carrying the same inserted sequence.

Coenzyme -- a dissociable, low-molecular weight, non-proteinaceous organic compound (often nucleotide) participating in enzymatic reactions as acceptor or donor of chemical groups or electrons.

C-peptide -- "Connecting peptide," a substance the pancreas releases into the bloodstream in equal amounts to insulin. A test of C-peptide levels shows how much insulin the body is making. (See peptide)

Creatinine -- a waste product from protein in the diet and from the muscles of the body. Creatinine is removed from the body by the kidneys; as kidney disease progresses, the level of creatinine in the blood increases.

Cyclic AMP(cAMP) -- 3'5'-cyclic ester of AMP. Generated from ATP by the action of adenyl cyclase that is coupled to hormone receptors by G-proteins (GTP-binding proteins). cAMP activates a specific (cAMP dependent) protein kinase and is inactivated by phosphodiesterase action giving 5'AMP. A molecule of AMP (adenosine monophosphate) in which the phosphate group is joined to both the 3' and the 5'positions of the ribose, forming a cyclic (ring) structure. When cAMP binds to CAP, the complex is a positive regulator of procaryotic transcription.

Cyclic GMP (cGMP) -- 3'5'-cyclic ester of GMP. A second-messenger generated by guanylyl cyclase.

Cytokeratin (19) -- A protein that is considered a marker for ductal pancreatic cells.

Cytoplasm -- All the contents of a cell, including the plasma membrane,but not including the nucleus.

Dedifferentiation -- Changing back to a former phenotype of a cell. Loss of differentiated characteristics. In animals there is still controversy as to whether the undifferentiated cells of the blastema that forms at the end of an amputated amphibian limb (for example) are derived by dedifferentiation, or by proliferation of uncommitted cells. Neither is it clear whether dedifferentiation in animal cells might just be the temporary loss of phenotypic characters, with retention of the determination to a particular cell type.

Diabetes Mellitus -- a condition characterized by hyperglycemia resulting from the body's inability to use blood glucose for energy. In type 1 diabetes, the pancreas no longer makes insulin and therefore blood glucose cannot enter the cells to be used for energy. In type 2 diabetes, either the pancreas does not make enough insulin or the body is unable to use insulin correctly.

Diabetogenic -- causing diabetes. For example, some drugs cause blood glucose levels to rise, resulting in diabetes.

Differentiate, Differentiation -- the process by which a cell is changed from a cell without a specific function to one more specialized, i.e., a cell with multipotential capabilities changed to one that produces insulin. Process in development of a multicellular organism by which cells become specialized for particular functions. Requires that there is selective expression of portions of the genome; the fully differentiated state may be preceded by a stage in which the cell is already programmed for differentiation but is not yet expressing the characteristic phenotype determination.

Diploid -- Having two different sets of chromosomes in the same nucleus of each cell.

DNA -- "deoxyribonucleic acid". The nucleic acid which carries the genetic code of an organism. It is the primary component ofchromosomes. Computer Model of the DNA Helix 4

Docking studies -- molecular modeling studies aiming at finding a proper fit between a ligand and its binding site.

Docosahexaenoic acid (DHA) -- A long chain omega-3 fatty acid containing 22 carbon atoms and six unsaturations (C22:6 n-3); one of the most unsaturated fatty acid found in nature. It is found mainly in fish and marine microorganisms and plants. Considered, along with EPA, to be the major reason for the beneficial effects of fish oils on the cardiovascular system. DHA is a precursor to series 3 eicosanoids that promote dilation of blood vessels and a slower blood clotting reaction and, as such, has been found to be critical to the maintenance of normal cardiovascular health. DHA is also an essential component of the brain, eyes, and other nervous system tissues. It is especially important for the full development of the nervous system in the fetus and newborn.

Double membrane -- In mitochondria and plastids, there is a two-layered membrane which surrounds the organelle. This is believed to be the result of endosymbiosis, with the outer membrane coming from the eukaryotic cell, and the inner membrane belonging to the original prokaryote which was "swallowed".

Ductal epithelium --

Dysfunction -- the pathological condition whereby the cell or portion of a cell (i.e., mitochondria) is not functioning normally.

Dyslipidemia -- The state in which lipids are in dysfunctional condition whereby total cholesterol, LDL's, VLDL's, and triglycerides are at a high level and HDL is at a low level. Often associated with diabetes and the metabolic syndrome.

Efficacy -- the relative intensity with which agonists vary in the response they produce even when they occupy the same number of receptors and with the same affinity. Efficacy is not synonymous to Intrinsic activity. DNA contains 2-deoxy-D-ribose as the sugar component.

Eicosanoids -- A family of hormone-like substances formed from arachidonic acid (AA) and gamma-linolenic acid (GLA), both omega-6 acids, and eicosapentaenoic acid (EPA), an omega-3 acid. Eicosanoids in the human body are mainly formed from arachidonic acid. Two main types of eicosanoids are prostaglandins and leukotrienes. Eicosanoids control or influence blood pressure, blood clotting, immune function, allergic response and other processes. In general, eicosanoids derived from omega-3 and omega-6 fatty acids have opposite effects.

Eicosapentaenoic acid (EPA) -- A long chain omega-3 fatty acid containing 20 carbon atoms and five unsaturations (C20:5n-3). Found predominantly in fish and fish oil. Considered, along with DHA, to be the major reason for the beneficial effects of fish oils on the cardiovascular system. EPA is the direct precursor to series 3 eicosanoids (see DHA).

Epithelium --

Endocrine gland -- a group of specialized cells that release hormones into the blood. For example, the islets in the pancreas, which secrete insulin, are endocrine glands. Gland that secretes directly into blood and not through a duct. Examples are pituitary, thyroid, parathyroid, adrenal glands, ovary and testis, placenta and B cells of pancreas.

Endopeptidase -- The enzymes within the secretory granules of the beta cells that convert proinsulin into C peptide and insulin.

Endoplasmic Reticulum -- (ER) network of membranes in eukaryotic cells which helps in control of protein synthesis and cellular organization.

Enterocytes -- Combined expression of pancreatic duodenal homeobox 1 (Pdx-1) and islet factor 1 (Isl-1)induces immature enterocytes (IEC-6)to produce insulin. Results indicated that immature intestinal stem cells can differentiate into insulin-producing cells given the ability to express the transcription factors Pdx-1 and Isl-1. Source: 5

Enzyme -- a complex protein which helps to speed biochemical reactions. Enzymes are important in the construction and degradation of other molecules. A protein made by the body that brings about a chemical reaction, for example, the enzymes produced by the gut to aid digestion. An enzyme is a macromolecule, usually a protein, that functions as a (bio) catalyst by increasing the reaction rate.

Enzyme induction -- the process whereby an (inducible) enzyme is synthesized in response to a specific inducer molecule. The inducer molecule (often a substrate that needs the catalytic activity of the inducible enzyme for its metabolism) combines with a repressor and thereby prevents the blocking of an operator by the repressor leading to the translation of the gene for the enzyme.

Enzyme repression -- the mode by which the synthesis of an enzyme is prevented by repressor molecules.

Essential Fatty Acids -- The fatty acids that the body cannot synthesize efficiently but needs for normal metabolism. These include linoleic acid (LA) and alpha-linolenic acid (ALA). Deficiency of essential fatty acids, a rare occurrence, can lead to certain skin diseases and decreased neurological function. DHA and EPA are considered by some to be conditionally essential fatty acids; they can be manufactured from LA and LNA by the body but only at a low and potentially insufficient rate.

Enterocytes -- Cells of the intestinal epithelium.

Enteroendocrine hormones -- A term that recognizes the gut as an endocrine organ.

Euglycemia -- a normal level of glucose in the blood.

Eukaryotes -- are so diverse that it isn't easy to generalize about their life histories and ecological roles. However, a particular method of cell division is found in most eukaryotes: this is mitosis. Source: 6

Eukaryote DNA -- It is divided into linear pieces called chromosomes (unlike bacterial DNA, which forms loops). In the non-dividing phase of a eukaryotic cell's life cycle, known as interphase, the chromosomes are uncoiled. When a eukaryotic cell prepares to divide, first the DNA in the chromosomes replicates, creating doubled chromosomes, and then the chromosomes begin to coil and supercoil upon themselves, in the stage known as prophase. At this point the chromosomes become thick enough to be seen under the light microscope. Next, in metaphase, the chromosomes line up in the center of the nucleus (in some eukaryotes the nuclear membrane disappears, in others it does not). The chromosomes then are pulled apart to opposite sides of the cell, in anaphase. Lastly, in telophase, the chromosomes uncoil, and the nuclear membrane re-forms if it disappeared. At this time, cytokinesis - the actual splitting of the whole cell - takes place. In eukaryotes with no cell wall, the daughter cells generally pinch off from each other; in eukaryotes with cell walls, a new cell wall forms and partitions the parent cell into two.

Eukaryotic -- Literally "true nucleus", the term applies to all protists, plants, animals, and fungi. Eukaryotic cells have internal membranes which partition them into regions for different functions, such as mitochondria, plastids, the ER, Golgi apparatus, etc. They also possess a cytoskeleton which helps them control their shape.

Extracellular matrix -- (ECM) Region outside of metazoan cells which includes compounds attached to the plasma membrane, as well as dissolved substances attracted to the surface charge of the cells. The ECM functions both to keep animal cells adhered together, and well as buffering them from their environment.

Ex Vitro -- The term seems to be used with plant propigation.

Ex Vivo -- A study was performed on outside the body. Ex vivo and in vitro have some simularities in that they are outside of the body.

Fat -- A class of chemical compounds that contain one or more fatty acid(s); insoluble in water. Fat is one of the three main constituents of food, the others being protein and carbohydrate. Fat is also the principal form in which energy is stored in the body. Vegetable oils, butter, margarine, salad dressing, oil, nuts, meat, poultry, fish, and some dairy products are common examples of fat. Excess calories are stored as body fat (adipose), providing the body with a reserve supply of energy and other functions. (See Triglycerides.)

Fatty acids -- Chemically R-COOH where R is an aliphatic moiety and COOH is the carboxyl terminal . The common fatty acids of biological origin are linear chains with an even number of carbon atoms. Free fatty acids are present in living tissues at low concentrations. The esterified forms are important both as energy storage molecules and structural molecules. They are the building blocks of fats and that which gives fats their physical and biological properties. Fatty acids can be saturated or unsaturated (" trans ", monounsaturated, polyunsaturated, highly unsaturated) and they can be short chain or long chain. Fatty acids are also a major component of cellular membranes where they contribute to the fluidity and proper functioning of the membrane. Long chain, highly unsaturated fatty acids such as DHA, EPA, and AA are precursors to the hormone-like eicosanoids that influence many bodily functions. Very long chain fatty acids often have names that don't readily identify them in this group.

Free radicals -- Highly chemically reactive molecules which can rapidly alter or destroy certain sensitive neighboring molecules. Destructive chain reactions initiated by free radicals within body tissues can cause cancer, diabetes and atherosclerosis. Potential damage to food products include off flavors, odors, tastes, and colors. Antioxidants can control the reactivity of these free radicals.

Fructosamine test -- measures the number of blood glucose molecules linked to protein molecules in the blood. The test provides information on the average blood glucose level for the past 3 weeks.

Gene -- Originally defined as the physical unit of heredity but the meaning has changed with increasing knowledge. It is probably best defined as the unit of inheritance that occupies a specific locus on a chromosome, the existence of which can be confirmed by the occurrence. It consists of chain-like molecules of nucleic acids - deoxyribonucleic acid (DNA) in most organisms and ribonucleic acid (RNA) in certain viruses - and is usually associated in a linear arrangement that(in part) constitutes a chromosome. It is also the segment of DNA that is involved in producing a polypeptide chain. It includes regions preceding and following the coding region (leader and trailer) as well as intervening sequences (introns) between individual coding segments (exons).

Gene coding sequence -- The region of a gene (DNA) that encodes the amino acid sequence of a protein.

Gene expression -- The full use of the information in a gene via transcription and translation leading to production of a protein and hence the appearance of the phenotype determined by that gene. Gene expression is assumed to be controlled at various points in the sequence leading to protein synthesis and this control is thought to be the major determinant of cellular differentiation in eukaryotes.The expression of genes due to some other influence. In clinical studies it is measured in terms of the level of a particular (messenger = m) mRNA. Phenotype relates to a specific kind of genotype in a gene expression.

Gene transcription --

Genome -- the complete set of chromosomal and extrachromosomal genes of an organism, a cell, an organelle or a virus; the complete DNA (deoxyribonucleic acid) component of an organism.

Genotype -- The genetic constitution of an organism or cell, as distinct from its expressed features or phenotype.The total genetic, or hereditary, constitution that an individual receives from its parents. An individual organism's genotype is distinguished from its phenotype, which is its appearance or observable character.

Gland -- a group of cells that secrete substances. Endocrine glands secrete hormones. Exocrine glands secrete salt, enzymes, and water.

Glucagon -- a hormone produced by the alpha cells in the pancreas. It raises blood glucose. An injectable form of glucagon, available by prescription, may be used to treat severe hypoglycemia.

Gluconeogenesis -- Synthesis of glucose from non-carbohydrate precursors, such as pyruvate, amino acids and glycerol. Takes place largely in liver, and serves to maintain blood glucose under conditions of starvation or intense exercise.

Glucagon-like Peptide 1 (GLP-1)-- A peptide hormone secreted from the distal part of the small intestine and the colon in response to meal ingestion. It plays an important role as an incretin hormone, stimulating insulin secretion, and also functions as one of the hormones of the "ileal brake," the endocrine inhibition of upper gastrointestinal motility and secretion elicited by the presence of unabsorbed nutrients in the ileum. Clinical trials have been conducted with long-acting GLP-1 derivative (NN2211)as well as with synthetic Exendin-4 (AC2993), a long-acting potent agonist of the glucagon-like peptide 1 (GLP-1) receptor, to ameliorate glycemia and (to increase beta cell mass - NN2211 only). Exendin-4 reduces fasting and postprandial glucose and decreases energy intake in healthy volunteers." Source: Click

Glucose -- simple sugar, and the primary product of photosynthesis. It is polymerized to make cellulose and chitin. one of the simplest forms of sugar. A prime fuel for the generation of energy by organisms. It is broken down (to obtain energy) via a metabolic process called glycolysis. Glucose is a hexose, a sugar possessing six carbon atoms in its molecule. The six carbon atoms are connected to each other to form a closed ring structure known as a hexose (6) ring. Animal cells store glucose in the form of glycogen (sometimes called animal starch), a large branched polymer of glucose units.

Glucotoxicity -- The diabetogenic effect of elevated blood glucose concentrations rather than of concurrent abnormalities in circulating insulin concentrations, insulin secretion, or insulin action. Although difficult to measure, increased plasma glucose may lead to altered levels of intracellular glucose; thus, the term "glucotoxicity" generally refers to blood glucose. Glucotoxicity is manifest in the liver, muscle, and pancreatic islets. toshow=&HITS=10&hits=10&RESULTFORMAT=&fulltext=GLP-1+&searchid=1037056974911_1530&stored_search=&FIRSTINDEX=10&journalcode=ajpendo">7

Glycated hemoglobin -- (See HbA1/c)

Glycogen -- the form of glucose found in the liver and muscles.

Glycoprotein -- a membrane-bound protein which has attached branching carbohydrates. These may function in cell-cell recognition, such as in human blood groups and immune system response, as well as in resisting compression of cells.

Glycosylation -- A process were glucose attaches to protein. Glycated hemoglobin as measured by the HbA1/c test is the measure diabetics are most familiar with. The most frequent type of intracellular glycosylation is O-linked N-acetylglucosamine (GlcNAc).

Growth/differentiation factors -- Members of the TGF-beta family of growth factors.

Haploid -- Having a single set of chromosomes in the nucleus of each cell.

HbA1/c -- A test that measures glycated hemoglobin. Hemoglobin is the part of a red blood cell that carries oxygen to the cells and sometimes joins with the glucose in the bloodstream. Also called hemoglobin A1C or glycosylated hemoglobin, the test shows the amount of glucose that sticks to the red blood cell, which is proportional to the amount of glucose in the blood.

Hepatic -- pertaining to the liver or cell types usually in the liver.

Heteroreceptor -- a receptor regulating the synthesis and/or the release of mediators other than its own ligand (See also Autoreceptor).

HDL cholesterol, stands for high-density-lipoprotein cholesterol -- a fat found in the blood that takes extra cholesterol from the blood to the liver for removal. Sometimes called "good" cholesterol.

Hedgehog signalling proteins --

Helix -- the structure of DNA is described as a helix. It is a spiral shaped structure of nucleoside pairs. In most clinical studies the components of this structure are listed for DNA and RNA. (See nucleoside).

Hemoglobin -- protein complex found in the blood of most chordates and the roots of certain legumes. It binds oxgen molecules, and in chordates serves as the means by which the oxygen is supplied to the cells of the body.

Hepatocyte -- liver cells: Usually implies hepatocytes, even though other cell types are found in the liver (Kupffer cells for example). Hepatocytes are relatively unspecialised epithelial cells and are the biochemist's "typical animal cell".

Hepatocyte nuclear factor (HNF)-1 alpha and HNF-4 alpha -- HNF-1 alpha function is now known to have distinct properties in pancreatic ß-cells. It controls a complex tissue-selective genetic network that is activated when pancreatic cells differentiate, and allows these cells to maintain critical specialized functions. The network contains an indispensable core component formed by a positive cross-regulatory feedback circuit between HNF-1 alpha and HNF-4 alpha . This type of circuit configuration can exhibit a switch-like behavior with two stable states. In the default active state, it can serve to perpetuate network activity in differentiated ß-cells. However, the loss of one HNF-1 alpha or HNF-4 alpha allele can increase the probability that the feedback circuit is permanently switched off, resulting in decreased expression of all four alleles selectively in ß-cells.8

High blood glucose -- see hyperglycemia.

High density lipoproteins (HDL) -- Particles in the blood stream composed of triglycerides ("fat"), cholesterol and other lipids and protein with a relatively low proportion of lipid and a relatively high proportion of protein. They make lipids more soluble and dispersible in blood, and their main function is to carry cholesterol. Generally considered to be beneficial to cardiovascular health.

Histones -- proteins attached to the DNA of eukaryotes which allows it to be packaged into chromosomes.

Hormone -- a chemical produced in one part of the body and released into the blood to trigger or regulate particular functions of the body. For example, insulin is a hormone made in the pancreas that tells other cells when to use glucose for energy. Synthetic hormones, made for use as medicines, can be the same or different from those made in the body. A hormone is a substance produced by endocrine glands, released in very low concentration into the bloodstream, and which exerts regulatory effects on specific organs or tissues distant from the site of secretion.

Hydrogenated fat -- A fat that has been chemically altered by the addition of hydrogen atoms to the unsaturated fatty acids in the fat. Vegetable oil and margarine are examples of hydrogenated fats. Can lead to the production of trans fatty acids.

Hydrophilic -- "water loving". Hydrophilic compounds dissolve easily in water, and are usually polar.

Hydrophilicity is the tendency of a molecule to be solvated by water.

Hydrophobic -- "water fearing". Hydrophobic compounds do not dissolve easily in water, and are usually non-polar. Oils and other long hydrocarbons are hydrophobic.

Hydrophobicity is the association of non-polar groups or molecules in an aqueous environment which arises from the tendency of water to exclude non polar molecules. (See also Lipophilicity).

Hyperamylinemia -- Elevated levels of amylin.

Hyperglycemia -- excessive blood glucose. Fasting hyperglycemia is blood glucose above a desirable level after a person has fasted for at least 8 hours. Postprandial hyperglycemia is blood glucose above a desirable level 1 to 2 hours after a person has eaten.

Hyperinsulinemia -- a condition in which the level of insulin in the blood is higher than normal. Caused by overproduction of insulin by the body. Related to insulin resistance.

Hyperlipidemia -- higher than normal fat and cholesterol levels in the blood. Dyslipidemia is the term usually used in relationship to diabetes.

Hypertension -- a condition present when blood flows through the blood vessels with a force greater than normal. Also called high blood pressure. Hypertension can strain the heart, damage blood vessels, and increase the risk of heart attack, stroke, kidney problems, and death.

Hypoglycemia -- a condition that occurs when one's blood glucose is lower than normal, usually less than 70 mg/dL. Signs include hunger, nervousness, shakiness, perspiration, dizziness or light-headedness, sleepiness, and confusion. If left untreated, hypoglycemia may lead to unconsciousness. Hypoglycemia is treated by consuming a carbohydrate-rich food such as a glucose tablet or juice. It may also be treated with an injection of glucagon if the person is unconscious or unable to swallow. Also called an insulin reaction.

Hypotension -- low blood pressure or a sudden drop in blood pressure. Hypotension may occur when a person rises quickly from a sitting or reclining position, causing dizziness or fainting.

Ilotropin -- A protein extract derived from the INGAP gene. The extract is multiplied by using recombinant molecular biological techniques.

Immature intestinal stem cells (IEC-6) -- "These results indicated that combined expression of Pdx-1 and Isl-1 in IEC-6 cells was required for the production of insulin. ... immature intestinal stem cells can differentiate into insulin-producing cells given the ability to express the transcription factors Pdx-1 and Isl-1." Source: Combined Expression of Pancreatic Duodenal Homeobox 1 and Islet Factor 1 Induces Immature Enterocytes to Produce Insulin

Immortal cell lines -- The results from a number of transfection experiments, show that all of the immortalized cells possess robust recombination activity, while the normal fibroblasts are significantly less recombinogenic. Expression of telomerase is usually required for cell immortalization and long-term tumor growth. (Additional information:Two Novel Immortal Pancreatic b-Cell Lines Expressing and Secreting Human Islet Amyloid Polypeptide Do Not Spontaneously Develop Islet Amyloid) Characterization of homologous DNA recombination activity in normal and immortal mammalian cells -- 10 (Also see telomerase)

INGAP -- An acronym for islet neogenesis associated protein. INGAP is a gene that stimulates the regeneration and growth of insulin secreting islet cells from immature stem cells. This gene recognizes proteins that have the potential to produce islet cells as well as to encourage growth of these insulin-producing cells in the panceras. (See ilotropin)

Insulin -- a hormone that helps the body use glucose for energy. The beta cells of the pancreas make insulin. When the body cannot make enough insulin, insulin is taken by injection or through use of an insulin pump.

Insulin promoter factor 1 (IPF-1) -- a homeodomain protein which in the adult pancreas is selectively expressed in the beta-cells and which binds to and transactivates the insulin promoter. Source: 11

Insulin receptors -- areas on the outer part of a cell that allow the cell to bind with insulin in the blood. When the cell and insulin bind, the cell can take glucose from the blood and use it for energy.

Insulin resistance -- the body's inability to respond to and use the insulin it produces. Insulin resistance may be linked to obesity, hypertension, and high levels of fat in the blood.

In vitro -- Literally, in glass; general term for cells in culture as opposed to in a multicellular organism.

In vivo -- Literally, in life; used of cells in their natural multicellular environment or of experiments done on intact organism rather than on isolated cells in culture.

Ion -- an atom or small molecule which carries a positive or negative charge.

Islet duodenum homeobox-1 (IDX-1) -- A homeodomain transcription factor that is is a critical regulator of pancreatic development and insulin gene transcription. Cells expressing Pdx-1 give rise to all three types of pancreatic tissue: exocrine, endocrine and duct. The role of the transcription factor IPF-1 in islet neogenesis is supported by its enhanced expression in pancreatic ducts (the site of endocrine cell precursors) in various models of pancreatic regeneration. (Also abbreviated PDX-1, IPF-1, and STP-1) 12

Islet factor 1 (Isl-1) --

Islet neogenesis --

Islet progenitors -- In development a "parent" cell that gives rise to a distinct cell lineage by a series of cell divisions.

Islet transplantation -- moving the islets from a donor pancreas into a person whose pancreas has stopped producing insulin. Beta cells in the islets make the insulin that the body needs for using blood glucose.

Islet trophic factor --

Islets of Langerhans -- groups of cells located in the pancreas that make hormones that help the body break down and use food. Islets contain many capillaries The three primary cell types within the pancreatic islets are beta cells which produce and secrete insulin, amylin, C peptide, proinsulin, and preproinsulin; alpha cells which sythesize glucagon; sigma cells which synthesize somatostatin; and other cells - pancreatic polypeptide, D1, and enterochomaffin.

LDL cholesterol -- Stands for low-density lipoprotein cholesterol -- a fat found in the blood that takes cholesterol around the body to where it is needed for cell repair and also deposits it on the inside of artery walls. Sometimes called "bad" cholesterol.

Leptin --

Ligand -- Any molecule that binds to another; in normal usage a soluble molecule such as a hormone or neurotransmitter, that binds to a receptor. The decision as to which is the ligand and which the receptor is often a little arbitrary when the broader sense of receptor is used (where there is no implication of transduction of signal). In these cases it is probably a good rule to consider the ligand to be the smaller of the two - thus in a lectin-sugar interaction, the sugar would be the ligand (even though it is attached to a much larger molecule, recognition is of the saccharide).

Lipids -- a class of biochemical compounds which includes fats, oils, and waxes. A term for fat in the body. Lipids can be broken down by the body and used for energy.They are insoluble in water but soluble in certain organic solvents. These include fatty acids,neutral fats (triglycerides), waxes, cholesterol, steroids and phosphatides.

Lipid profile -- a blood test that measures total cholesterol, triglycerides, and HDL cholesterol. LDL cholesterol is then calculated from the results. A lipid profile is one measure of a person's risk of cardiovascular disease.

Lipophilicity -- The affinity of a molecule or a moiety for a lipophilic environment. It is commonly measured by its distribution behaviour in a biphasic system, either liquid-liquid (e.g., partition coefficient in octan-1-ol/water) or solid/liquid (retention on reversed-phase high performance liquid chromatography (RP-HPLC) or thin-layer chromatography(TLC) system). (See also Hydrophobicity).

Lipotoxicity -- The diabetogenic effect of increased circulating free fatty acids or increased cellular fat content. This condition is manifest in several tissues, most notably the liver, muscle, and pancreatic islets.

Liver -- an organ in the body that changes food into energy, removes alcohol and poisons from the blood, and makes bile, a substance that breaks down fats and helps rid the body of wastes. Hepatic, pertaining to the liver.

Low density lipoproteins (LDL) -- Particles in the blood stream composed of triglycerides ("fat"), cholesterol and other lipids and protein with a relatively high proportion of lipid and a relatively low proportion of protein. They make lipids more soluble and dispersible in blood, and their main function is to carry cholesterol. Generally high levels are considered to be detrimental to cardiovascular health.

Lysosome -- Eukaryotic organelle which carries digestive enzymes. The lyzosome fuses with a vacuolar membrane containing ingested particles, which are then acted upon by the enzymes.

The Myc/Max/Mad network -- A group of transcription factors whose distinct interactions result in gene-specific transcriptional activation or repression.THE MYC/MAX/MAD NETWORK AND THE TRANSCRIPTIONAL CONTROL OF CELL BEHAVIOR

Mechanism(s) -- The physiological organism or activity that regulates, manages, changes, impacts, etc. from one state to another state.

Membrane -- 14

Metabolic phenotypes -- induced -- cellular mechanisms

Metabolic syndrome -- the tendency of several conditions to occur together, including obesity, insulin resistance, diabetes or pre-diabetes, hypertension, and high lipids.

Metabolism -- the term for the way cells chemically change food so that it can be used to store or use energy and make the proteins, fats, and sugars needed by the body. The term metabolism comprises the entire physical and chemical processes involved in the maintenance and reproduction of life in which nutrients are broken down to generate energy and to give simpler molecules (catabolism) which by themselves may be used to form more complex molecules (anabolism).

Meiosis -- A specialized form of nuclear division in which there are two successive nuclear divisions (meiosis I and II) without any chromosome replication between them. Each division can be divided into 4 phases similar to those of mitosis (pro-, meta-, ana- and telophase). Meiosis reduces the starting number of 4n chromosomes in the parent cell to n in each of the 4 daughter cells. Each cell receives only one of each homologous chromosome pair, with the maternal and paternal chromosomes being distributed randomly between the cells. This is vital for the segregation of genes. During the prophase of meiosis I (classically divided into stages: Leptotene, Zygotene, Pachytene, Diplotene and Diakinesis), homologous chromosomes pair to form bivalents, thus allowing crossing-over, the physical exchange of chromatid segments. This results in the recombination of genes. Meiosis occurs during the formation of gametes in animals, which are thus haploid and fertilization gives a diploid egg. In plants meiosis leads to the formation of the spore by the sporophyte generation.

Mitochondrial control of apoptosis -- 15 (nice slide presentation)

Mitochondrion -- Complex organelle found in most eukaryotes; believed to be descended from free- living bacteria that established a symbiotic relationship with a primitive eukaryote. Mitochondria are the site of most of the energy production in most eukaryotes; they require oxygen to function. See: double membrane.

Mitosis -- The process of nuclear division in eukaryotes. It is one step in cytokinesis, or cellular division. The usual process of nuclear division in the somatic cells of eukaryotes. Mitosis is classically divided into four stages. The chromosomes are actually replicated prior to mitosis during the S phase of the cell cycle. During the first stage prophase, the chromosomes condense and become visible as double strands(each strand being termed a chromatid) and the nuclear envelope breaks down. At the same time the mitotic spindle forms by the polymerization of microtubules and the chromosomesare attached to spindle fibres at their kinetochores. In metaphase the chromosomes align in a central plane perpendicular to the long axis of the spindle. This is termed the metaphase plate. During anaphase the paired chromatids are apparently pulled to opposite poles of the spindle by means of the spindle fibre microtubules attached to the kinetochore, though the actual mechanism for this movement is still controversial. This separation of chromatids is completed during telophase, when they can be regarded as chromosomes proper. The chromosomes now lengthen and become diffuse and new nuclear envelopes form round the two sets of chromosomes. This is usually followed by cell division or cytokinesis in which the cytoplasm is also divided to give two daughter cells. Mitosis ensures that each daughter cell has a diploid set of chromosomes that is identical to that of the parent cell. 16

Molecular interaction map -- 17

Multipotential -- In cells the potential to change into a variety of specific cell types. Synonymous with pluripotential.

Mutagen -- an agent that causes a permanent heritable change (i.e., amutation) into the DNA (deoxyribonucleic acid) of an organism.

Necrosis -- Death of some or all cells in a tissue as a result of injury, infection or loss of blood supply.

Nestin (neural stem cell protein) -- Large (200 kD) intermediate filament protein found in the developing brain. Functionally similar to other intermediate filament proteins but the sequence is very different. This protein has also been found in the panceras. "... human pancreatic islets contain a heretofore unrecognized distinct population of cells that express the neural stem cell–specific marker nestin." (See nestin-positive stem cells)

Nestin-positive stem cells -- "Nestin-positive cells within pancreatic islets express neither the hormones insulin, glucagon, somatostatin, or pancreatic polypeptide nor the markers of vascular endothelium or neurons, such as collagen IV and galanin. Focal regions of nestin-positive cells are also identified in large, small, and centrolobular ducts of the (rat) pancreas. Nestin-positive cells in the islets and in pancreatic ducts are distinct from ductal epithelium because they do not express the ductal marker cytokeratin 19 (CK19)." Source: Multipotential Nestin-Positive Stem Cells Isolated From Adult Pancreatic Islets Differentiate Ex Vivo Into Pancreatic Endocrine, Exocrine, and Hepatic Phenotypes

Neogenesis -- New development or origin. Particularly for this glossary, the development or proliferation of new pancreatic cells.

NIP cells --

Nuclear membrane -- The double membrane which surrounds the eukaryotic nucleus. It has many pores in its surface which regulate the flow of large compounds into and out of the nucleus.

Nucleic acid -- class of biochemical compounds which includes DNA and RNA. They are among the largest molecules known. See DNA. A nucleic acid is a macromolecule composed of linear sequences of nucleotides that perform several functions in living cells, e.g., the storage of genetic information and its transfer from one generation to the next DNA (deoxyribonucleic acid), the expression of this information in protein synthesis (mRNA, tRNA) and may act as functional components of subcellular units such as ribosomes (rRNA).

Nucleoid -- Region in prokaryotes where the DNA is concentrated. Unlike a nucleus, it is not bound by a membrane.

Nucleotide -- unit from which nucleic acids are constructed by polymerization. It contains a sugar, a phosphate group, and an organic base. ATP is a nucleotide. (See base.)

Nucleus -- Membrane-bound organelle which contains the DNA in the form of chromosomes. It is the site of DNA replication, and the site of RNA synthesis.

Nucleoside -- a compound in which a purine or pyrimidine base is bound via a N-atom to C-1 replacing the hydroxy group of either 2-deoxy-D-ribose or of D-ribose, but without any phosphate groups. (See also nucleotide). The common nucleosides in biological systems are adenosine, guanosine, cytidine, and uridine (which contain ribose) and deoxyadenosine, deoxyguanosine, deoxycytidine and thymidine (which contain deoxyribose). (See helix and base).

Nucleotide -- a nucleoside in which the primary hydroxy group of either 2-deoxy-D-ribose or of D-ribose is esterified by orthophosphoric acid.

Oligonucleotide -- an oligomer resulting from a linear sequences of nucleotides.

Omega-3 -- Refers to the third carbon-carbon bond from the carbon-terminal end of a fatty acid molecule which is unsaturated. omega-3 fatty acids are found in fish, marine plants, and some terrestrial plants.

Omega-6 -- Refers to the sixth carbon-carbon bond from the carbon-terminal end of a fatty acid molecule which is unsaturated. omega-6 fatty acids are found mainly in vegetable oils and animal fat.

Organelle -- Membrane-bound structure in a eukaryotic cell. Organelles partition the cell into regions which carry out different cellular functions. Mitochondria, the ER, and lysosomes are examples of organelles.

Oxidation -- Addition of oxygen to a chemical structure. Oxidation occurs in the use of lipids and glucose as energy sources in the cells. In oils, oxidation causes rancidity and may be a possible source of the carcinogenic property of some oils, particularly used in cooking at excessive temperatures.

Pancreas -- an organ that makes insulin and enzymes for digestion. The pancreas is located behind the lower part of the stomach and is about the size of a hand. It's exocrine duct is onthe duodenum (the top part of the small intestine), near the duct for the gall bladder.

Pancreatic cell/tissue phenotypes -- Ducts, endocrine, and exocrine

Pancreas duodenal homeobox 1 (PDX-1)-- a transcription factor critical for pancreatic development and endocrine cell neogenesis, in human pancreatic ductal cells derived from cultured exocrine tissue. In vitro, exocrine cells rapidly adhered and were de-/transdifferentiated to ductal cells with a dramatic loss of amylase protein and a simultaneous increase of ductal cytokeratin 19 protein. IPF-1 protein and mRNA levels were low to undetectable in exocrine preparations before culture. After culture, an increase in IPF-1 protein was observed. Increase in IPF-1 mRNA levels after culture was observed. 18

Partial agonist -- an agonist which is unable to induce maximal activation of a receptor population, regardless of the amount of drug applied.

Pathological -- usually refers to a diseased state of an organism. Physiological is often considered the normal state and pathological the abnormal state.

Pax gene family -- Some members of this family are Pax6 which is expressed in all endocrine cells and Pax4 which is restricted to developing beta cells.19 (Other factors in endocrine cell development are discussed in this article.)

Peptidomimetic -- a compound containing non-peptidic structural elements that is capable of mimicking or antagonizing the biological action(s) of a natural parent peptide. A peptidomimetic does no longer have classical peptide characteristics such as enzymatically scissille peptidic bonds. (See also peptoids).

Peptoid -- a peptidomimetic that results from the oligomeric assembly of N-substituted glycines.

Peroxisomes -- Small membrane bound vessels containing oxidative enzymes. Catalase protects the cell from oxidative damage.Enzymes involved lipid metabolism are found in the peroxisomes. Peroxismal enzymes are synthesized in free cytosolic ribosomes and then directed to the peroxisomes.

Peroxisome proliferator-activated receptor (PPAR)-- There are at least three isoforms of the PPAR. The PPARgamma transcription factor has a key role in adipocyte (fat cell) differentiation. The ligands, such as the glitazone, for PPARgamma are known to reduce insulin resistance and result in the redistribution of fat. Miscellaneous sources: Peroxisome Proliferator search Diabetes journal #cc0099

Phenotype -- The characteristics displayed by an organism under a particular set of environmental factors, regardless of the actual genotype of the organism.

Phenotypic switch -- Rapid de-/transdifferentiation of exocrine cells cultured in vitro is associated with an increase in ductal markers and in the transcription factor IPF-1 on a protein and mRNA level. The authors of the study cited here say the results may endorse the old hypothesis of the transdifferentiation of acinar cells into endocrine islets. Pancreatic exocrine cells transiently coexpress amylase and IPF-1 during development. In adult differentiated acinar cells, IPF-1 expression remains controversial. Exocrine cells are easily obtained from human pancreases and may prove to be a particularly abundant source of beta-cell precursors for allogenic cell therapy in type 1 diabetes. Source: 21

Phosphate -- an ion consisting of a phosphorus atom and four oxygen atoms. Among other things, it is used in the constuction of nucleic acids.

Phosphorylation -- The introduction of a phosphate group into a molecule. Formation of a phosphate derivative of a biomolecule, usually by enzymatic transfer of a phosphate group from ATP. A process involving the transfer of a phosphate group (catalyzed by enzymes) from a donor to a suitable acceptor; in general an ester linkage is formed, for example: ATP + alcohol ADP + phosphate ester. Particularly in type 2 diabetic patients, the major site of impairment of insulin action resides in skeletal muscle, where glucose metatabolism is abnormal because of an impairment of insulin-stimulated glycogen synthesis associated with a defect in glucose transport and/or glucose phosphorylation.

Placebo -- an inert substance or dosage form which is identical in appearance, flavor and odour to the active substance or dosage form. It is used as a negative control in a bioassay or in a clinical study.

Plasma membrane -- Outer membrane of a cell, sometimes called the cell membrane. The term plasma membrane is used more frequently when discussing prokaryotes.

Plasmid -- Circular loop of DNA in prokaryotes. Eukaryotic DNA is organized into chromosomes.

Pluripotent pancreatic stem cells --

Pluripotent stem cell -- Cells in a stem cell line capable of differentiating into several different final differentiated types, eg. there may be a pluripotent stem cell line for erythrocytes, granulocytes and megakaryocytes.

Polyunsaturated Fatty Acids (PUFA) -- Fatty acids with more than one unsaturated carbon-carbon bond. Oils with polyunsaturated fatty acids solidify at lower temperatures than oils with monounsaturated and saturated fatty acids. Such fatty acids are preferred to saturated fatty acids because they promote lower serum cholesterol levels and reduced risk of heart disease.

Preproinsulin -- The processing of the preprohormone, preproinsulin that begins insulin synthesis. Preproinsulin is converted to proinsulin by the removal of a 23 amino acid leader sequence.

Proinsulin -- the substance made first in the pancreas and then broken into several pieces to become insulin.

Proliferation -- In regard to cells, a process that increases their number.

Protein -- class of biochemical compounds constructed from amino acids. Proteins may be structural, such as those that make up hair and cartilage, or they may be reactive, such as the enzymes.

Regeneration -- Processes of repair or replacement of missing structures.

Receptor -- a molecule or a polymeric structure in or on a cell that specifically recognizes and binds a compound acting as a molecular messenger (neurotransmitter, hormone, lymphokine, lectin, drug, etc.).

Remodeling -- This refers to the change that takes place in an organ usually when a pathological state develops. In the pancereas the development of amyloid plaque deposit are considered remodeling. When plaque deposits occur in the arteries and atherosclerosis begins the, endothelium, cells that line the arteries become damaged. This remodeling causes endothelial dysfunction.

Renal -- having to do with the kidneys. A renal disease is a disease of the kidneys. Renal failure means the kidneys have stopped working.

Reverse transcriptase polymerase chain reaction; reverse transcription PCR (RT-PCR) -- PCR in which the starting template is RNA, implying the need for an initial reverse transcriptase step to make a DNA template. Some thermostable polymerases have appreciable reverse transcriptase activity; however, it is more common to perform an explicit reverse transcription, inactivate the reverse transcriptase or purify the product, and proceed to a separate conventional PCR.

Ribosome -- A heterodimeric multi-subunit enzyme composed of ribonucleoprotein and protein subunits. Interacts with aminoacylated tRNAs, and mRNAs and translates protein coding sequences from messenger RNA. During protein elongation, the nascent protein is held at the P-site(peptidyl-tRNA complex), while aminoacyl-tRNAs bearing new aminoacids are bound at the A-site. Similar ribosomes are found in all living organisms, all composed of large and small subunits, as well as chloroplasts and mitochondria. Differences are apparent between prokaryotic and eukaryotic ribosomes.

Ribozyme -- RNA with catalytic capacity - an enzyme made of nucleic acid not protein. Of particular interest because of the implications for self-replicating systems in the earliest stages of the evolution of (terrestrial) life.

RNA -- "ribonucleic acid". The nucleic acid which carries the DNA message into parts of the cell where it is interpreted and used. The 18S ribosomal RNA sequence has been used in many groups of organisms to reconstruct phylogeny. RNA contains D-ribose. A chemical similar to a single strand of DNA. In RNA, the letter U, which stands for uracil, is substituted for T in the genetic code. RNA delivers DNA's genetic message to the cytoplasm of a cell where proteins are made.

Saturated Fatty Acids -- Fatty acids with saturated structure (no unsaturated carbon-carbon bonds). Found in all fats, particularly animal fats. In excess, they are highly dangerous to body health, contributing to higher serum cholesterol levels and atherosclerosis.

Second messenger-- an intracellular metabolite or ion increasing or decreasing as a response to the stimulation of receptors by agonists, considered as the "first messenger". This generic term usually does not prejudge the rank order of intracellular biochemical events. Cyclic (cAMP) and Cyclic (cGMP) are common second messengers.

Sense primers -- Relate to particular mRNA. (See antisense primers)

Signal transducers and activators of transcription (STATs) -- Contain SH2 domains that allow them to interact with phosphotyrosine residues in receptors, particularly cytokine-type receptors; they are then phosphorylated by JAKs, dimerize and translocate to the nucleus where they act as transcription factors. Many STATs are known; some are relatively receptor-specific, others more promiscuous, so that a wide range of responses is possible with some STATs being activated by several different receptors, sometimes acting synergistically with other STATs.

Signal transduction pathways (STP) 22 Receptors Membrane receptors Nuclear receptors Non-receptor solute carriers (SLC) Intracellular STP enzymes Cross-talking among STPs Scaffolds in STPs Transcription factors in STPs

SIGNALLING WAYS 23

Somatostatin-transactivating factor-1 (STF-1) -- This homeobox-type somatostatin transactivating factor termed STF-1, which is uniformly expressed in cells of the endocrine pancreas and small intestine. (See Islet duodenum homeobox-1) Source: Characterization of somatostatin transactivating factor-1, a novel homeobox factor that stimulates somatostatin expression in pancreatic islet cells

Sorbitol (SORE-bih-tall) -- 1. A sugar alcohol (sweetener) with 4 calories per gram. 2. A substance produced by the body in people with diabetes that can cause damage to the eyes and nerves.

Starch -- another name for carbohydrate, one of the three main nutrients in food. A complex polymer of glucose, used by plants and green algae to store surplus sugar for later use.

Stem cells -- (1) Cell that gives rise to a lineage of cells. (2) More commonly used of a cell that, upon division, produces dissimilar daughters, one replacing the original stem cell, the other differentiating further (eg. stem cells in basal layers of skin, in haematopoietic tissue, and in meristems).

Sugar -- any of several small carbohydrates, such as glucose, which are "sweet" to the taste. 1. A class of carbohydrates with a sweet taste; includes glucose, fructose, and sucrose. 2. A term used to refer to blood glucose.

Sugar alcohols -- sweeteners that produce a smaller rise in blood glucose than other carbohydrates. Their calorie content is about 2 calories per gram. Includes erythritol, hydrogenated starch hydrolysates, isomalt, lactitol, maltitol, mannitol, sorbitol, and xylitol. Also known as polyols.

Telomerase -- The enzyme associated with telemeres. The synthesis of telomeres is mainly achieved by the cellular reverse transcriptase telomerase, an RNA-dependent DNA polymerase that adds telomeric DNA to telomeres. Expression of telomerase is usually required for cell immortalization and long-term tumor growth. In humans, telomerase activity is tightly regulated during development and oncogenesis. The modulation of telomerase activity may therefore have important implications in antiaging and anticancer therapy.

Telomere -- A special functional complex at the end of linear eukaryotic chromosomes, consisting of tandem repeat DNA sequences and associated proteins. It is essential for maintaining the integrity and stability of linear eukaryotic genomes. Telomere length regulation and maintenance contribute to normal human cellular aging and human diseases.

Transdifferentiation -- In the panceras this represents the change from one phenotype to another, i.e., whether it is from exocrine to ductal or to endocrine cells. Change of a cell or tissue from one differentiated state to another.

Transplant, transplanted -- the transfer of an organism from one person to another or from an individual to themselves via laboratory processing and in turn back to themselves.

Trans Fatty Acid -- An unsaturated fatty acid in which the atoms around the unsaturated bond are such that the molecule acts similarly to a saturated fatty acid. Frequently formed during hydrogenation of vegetable fats. Considered to be dangerous to body health.

Transcription -- Synthesis of RNA by RNA polymerases using a DNA template.

Transcription factors -- Protein required for recognition by RNA polymerases of specific stimulatory sequences in eukaryotic genes.

Transcription unit -- A region of DNA that is transcribed to produce a single primary RNA transcript, ie. a newly synthesized RNA molecule that has not been processed.

Triglycerides -- Common fat. Technically known as triacylglycerols. Made up of three molecules of fatty acid and one molecule of glycerol. Part of all blood lipids, especially the low density types, which are particularly harmful to the body. (See Fat.)

Undifferentiated cells -- usually progenerative cells or stem cells that need some other factor to change them into specific cell types.

Vascular -- relating to the body's blood vessels.

Vein -- a blood vessel that carries blood to the heart.

Very-low-density lipoprotein (VLDL) cholesterol -- a form of cholesterol in the blood; high levels may be related to cardiovascular disease. Particles in the blood stream composed of triglycerides ("fat"), cholesterol and other lipids and protein with an extremely high proportion of lipid and a low proportion of protein. They make lipids more soluble and dispersible in blood, and their main function is to carry cholesterol. Generally considered to be detrimental to cardiovascular health.

Xenobiotic -- a compound foreign to an organism (xenos [greek] = foreign). Health is Wholeness: Spirit, Soul. and Body
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