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anaphase The stage of mitosis or meiosis beginning with the separation of sister chromatids (or homologous chromosomes) followed by their movement towards the poles of the spindle.

anaphase-promoting complex Cyclosome An unusually complicated ubiquitin ligase, composed of 13 core subunits (total 1.5 MDa) and either of two loosely associated co-activators, Cdc20 and Cdhl, that is responsible for initiation of sister chromatid separation and the inactiva-tion of cyclin-dependent kinases. The largest subunit, Apcl, serves as a scaffold that associates independently with two separable subcomplexes, one that contains Apc2 (cullin), Apcll (RING) and Docl/ApclO, and another that contains the three tetratricopeptide repeat (TPR motif)-containing subunits (Cdc27, Cdcl6 and Cdc23). In S-phase, the APC is inactivated by binding of cyclin A.

anaphylatoxin Originally used as an antigen that reacted with an IgE antibody, thus precipitating reactions of ana-phylaxis. Now restricted to defining a property of complement fragments C3a and C5a, both of which bind to the surfaces of mast cells and basophils and cause the release of inflammatory mediators.

anaphylaxis As opposed to prophylaxis. A system or treatment that leads to damaging effects on the organism. Now reserved for those inflammatory reactions resulting from combination of a soluble antigen with IgE bound to a mast cell that leads to degranulation of the mast cell and release of histamine and histamine-like substances, causing localized or global immune responses. See hypersensitivity.

anaplasia Lack of differentiation, characteristic of some tumour cells.

anaplasmosis Bovine disease caused by protozoa of the genus Anaplasma that are found in red blood cells. Transmitted by ticks, biting flies and mosquitoes.

anaplerotic Anaplerotic reactions replenish TCA cycle intermediates and allow respiration to continue; for example, carboxylation of phosphoenolpyruvate in plants.

Anas platyrhynchos Mallard - from which domestic duck is derived by breeding (traditional genetic engineering).

anastomosis Joining of two or more cell processes or multicellular tubules to form a branching system. Anastomosis of blood vessels allows alternative routes for blood flow.

anastrozole A non-steroidal aromatase inhibitor that inhibits the production of estrogen, used in the treatment of advanced breast cancer. It significantly lowers serum oestradiol concentrations, and has no detectable effect on the formation of adrenal corticosteroids or aldosterone.

anatoxins A group of low-molecular weight neurotoxic alkaloids first described in the freshwater cyanobac-teria Anabaena flos-aquae, but subsequently found in other species. Anatoxin-a and homoanatoxin-a are secondary amines that bind and irreversibly activate nicotinic acetylcholine receptors; anatoxin-a(s) is the only natural organophosphate known and inactivates acetylcholine esterase in a similar fashion to synthetic organophosphate pesticides such as parathion and malathion. All cause muscle exhaustion by overstimulation and death through respiratory failure.

ANCA Antineutrophil cytoplasmic antibodies ANCA pos-itivity is seen in patients with a variety of inflammatory disorders, including IBD (inflammatory bowel disease), Wegener's granulomatosis and hepatobiliary disorders. Two forms are recognized: peripheral ANCA (p-ANCA), where the antigen seems to reside at the periphery of the nucleus; and cytoplasmic ANCA (c-ANCA), where the antigen is distributed throughout the cytoplasm of the neutrophil.

anchorage Attachment, not necessarily adhesive in character; because the mechanism is not assumed the term ought to be more widely used.

anchorage dependence The necessity for attachment (and spreading) in order that a cell will grow and divide in culture. Loss of anchorage dependence seems to be associated with greater independence from external growth control and is probably one of the best correlates of tumori-genic events in vivo. Anchorage independence is usually detected by cloning cells in soft agarose; only anchorage-independent cells will grow and divide (as they will in suspension).

anchored PCR Anchored polymerase chain reaction Variety of polymerase chain reaction in which only enough information is known to make a single primer. A known sequence is thus added to the end of the DNA, perhaps by enzymic addition of a polynucleotide stretch or by ligation of a known piece of DNA. The PCR can then be performed with the gene-specific primer and the anchor primer.

ancovenin An inhibitor of angiotensin I converting enzyme isolated from the culture broth of a Strepto-myces species; a l6-residue lantibiotic containing unusual amino acids such as threo-beta-methyllanthionine, meso-lanthionine and dehydroalanine. Streptoverticillium cinna-moneum produces a lantibiotic with similar properties, lanthiopeptin.

AND-34 A member of a novel family of proteins (NSPl, NSP2, and NSP3) that have an amino-terminal SH2 domain but bind by a carboxy-terminal GEF (Cdc25)-like domain to the carboxy-terminus of the focal adhesion adapter protein p130cas. Overexpression of AND-34 in epithelial breast cancer cells leads to activation of Rac and Cdc42 by a PI3K-dependent mechanism.

Andersen's syndrome An inherited human ion channel disorder (channelopathy) that has been linked to muscle abnormalities and developmental defects. The mutations affect a potassium channel called Kir2.l. Mutation is in gene KCNJ2 on Chrl7.

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Your Metabolism - What You Need To Know

Your Metabolism - What You Need To Know

If you have heard about metabolism, chances are it is in relation to weight loss. Metabolism is bigger than weight loss, though, as you will learn later on. It is about a healthier, better you. If you want to fire up your metabolism and do not have any idea how to do it, you have come to the right place. If you have tried to speed up your metabolism before but do not see visible results, you have also come to the right place.

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