| Alzheimer's Disease is one kind of the diseases which frequently happened to the old people.lt is usually divided into the family AD (FAD)and sporadic AD(SAD).About more than 90% of AD belongs to the sporadic kind. It is a degenerative disorder of the central nervous system characterized clinically by the loss of memory, intellectual,cognitive and behavior functions . AD has become one of the fourth lethal diseaseswhich could make the old people dead. There are more than twenty million people who are sufferred from it all over the world.Along with the increasing aged population,the charge of the nursing and cure for the AD sufferers will increase greatly.lt has become a problem which arosed abroad attention and make the scientists to find the method to cure it complately.The etiology and pathophysiology of AD are still unknown very clearly.According to its clinical characters,pathologic changes and molecular changes,the occurrence of AD is a result that many kinds of the factors beside the age interact with each other.To sum up ,there are mainly two kinds of theories: Firstly:The trauma theory of the cholinergic nerve.Ach has a consanguineous relation with the people's attention, cognitive functions and the behavior ability.The main pathological charters are the formation of the P -amyloid peptides outside the nerve cells and the formation of the neurous-fibrillary-tangles inside the nerve cells. Accordingly,they induce the loss of the neurons and the reduction of the synapses and so the action for the choline nerve to transfer the signals would be weakened.This theory considers that the formation of the 3-amyloid peptides is regulated and controled by the Ach.The reduction for the level of the Ach in nerve of the brain results in the loss of cognitive function and behavior function in AD's sufferers.These new developments are very powerful evidence for developing the drugs imitating the acetylcholine.The second one is the genetic theory.The studies have found that there are four kinds of genes (atleast)that are correlative with the occurrence of the familial AD including APP,PS1,PS2 and APOE.The mutation of these genes influences the formation of th 3 -amyloid peptides and the neurous-fibrillary-tangles.But how they induce these pathological changes is still not very clear. There are still not any so effective kinds of drugs to act on these targets in clinic.At the present, the inhibitors of the AchE are still the frequently used and the most effective drugs.Because there is no report about the AchE-inhibitors screened out from the actinomyces,it is probably to find out the new kinds of AchE-inhibitors from the fermentation of them.In the field of the agriculture,the organic phosphor and the amido formylesters were the insecticides which were broadly used for a long time.They have the same mechanism with the inhibition of the AchE.But those chemosynthesises with the same or the resembling active keyregiment used for a long time, it would be easy to bring up the nature of anti-drug to many kinds of the insects.Moreover,along with the development of the high-tech-agriculture and the requirement of the high potency and low poison's biochemical pesticides is needed increasely.lt cries for the new kinds of pesticides .The products from the microbes have such charcters with high-potency and low poison.In the soil there are some microbes to decompose them.So they will not result in the residul poison to the envirement.This shows that to develop the AchE-inhibitors from the microbes as medicine with great applying foreground inclinical medicine not only but also probablity to replace the old insecticides stage by stage.Moreover,it is very important for the protection of the people's health and the livestocks' together.Cholinesterases may be classified as AchE and BuchE on the basis of differential specificity of Ach and Buch hydrolysis.The research found 35 positive strains from more than 2000 strains of the actinomyces which could inhibit acetylcholinesterase by more than 50% using...
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