Stem intestinal

Trichinellosis is caused by the parasitic nematode Trichinella spiralis. This parasite has a complex life cycle that alternates between intestinal and muscle cell compartments of the host. This nematode infection is unusual because 7. spiralis is an intracellular parasite of mammalian cells. In addition, the broad host range of this parasite includes most mammals. The disease in humans has intrigued parasitologists, other biologists and public health workers for over a century (Cambell, 1983). The attraction to trichinellosis pardy stems from the debilitating and sometimes fatal effects that characterize this disease. 

A variety of type 2 cytokines and the non-lymphoid cell-derived growth factor, stem cell factor (SCF) (Hiiltner et al., 1989 Copeland et al., 1990 Huang et al., 1990 Thompson-Snipes et al., 1991 reviewed in Befus, 1995), are known to be important in the development of intestinal mast cell responses associated with nematode infection but the contribution of this population to host protection depends on the nematode species in question. 

A critical role for stem cell factor and c-kit in host protective immunity to an intestinal helminth. International Immunology 8, 559-567. 

Puddington, L., Olson, S. and Lefrancois, L. (1994) Interactions between stem cell factor and c-kit are required for intestinal immune homeostasis. Immunity 1,... 

Donaldson, L.E., Schmitt, E., Huntley, J.F., Newlands, G.F. and Grencis, R.K. (1996) A critical role for stem cell factor and c-kit in host protective immunity to an intestinal helminth. International Immunology 8, 559-567. 

The amonnt of protein synthesised and then released in (iv) and (v) is abont 70 g each day. Even under conditions of starvation or malnutrition, proliferation and differentiation of stem cells located in the crypts of the villi are important to provide the cells necessary for replenishment of those lost from the villi. New cells move up the villus to replace those lost at the top. Under these conditions, amino acids are not available from the intestine and have to be taken up from the blood across the basolateral membrane. A low level of amino acids in the blood, due to chronic malnutrition, will prevent or reduce the rate of proliferation of these cells, so that digestion of even the small amount of food ingested during malnutrition, or refeeding after starvation, is difficult. A vicious circle thus results from protein-deficient diets which increase the risk of development of protein-energy-malnutrition. This is especially severe in children but may also contribute to the clinical problems that occur in the elderly whose diets are of low quality. 

Between them, the bone marrow and the small intestine possess the highest number of proliferating cells in the body. The bone marrow contains stem cells which proliferate and differentiate to produce red and white blood cells (Chapter 17). This requires not only this amino acids to support protein synthesis but also glutamine, both as a fuel and as a precursor for nucleotides, as in the other proliferating cells. The pathway for metabolism of glutamine in cells isolated from the bone marrow is similar to that in lymphocytes (Figure 8.28). 

Continually renewing the tissue contains cells that proliferate continually to replace those that die or are lost (e.g. the skin, intestine, bone marrow). These cells are known as stem cells. 

Cirsium chinense Gardn. et Champ. C. japonicum DC Chinese Ji Da Ji (Thistle) (leaf, stem) Alpha-amyrin, beta-amyrin, beta-sitosterol, stigmasterol, taraxsteryl acetate, inulin, labenzyme, pcctolinarin.50 60 Hemostat, diuretic, treat intestinal bleeding caused by ulcers, externally for abscesses and scabies. 

Melia japonica G. Don M. toosendan L. M. azedarach L. Chuan Lian or Ku Lian Ku Lian Pi or Ku Lian Chi (Chinaberry tree) (stem, root bark) Toosendanin, nimbin, kulinone, methylkulonate, melianol, gedunin, melianodiol, melianotriol, melialactone, azadarachtin, nimbolins, fraxinella, palmitic acid, lauric acid, valerianic acid, butyric aicd, stearic acid, cycloencalenol.33-49 144 This herb is toxic. Treat intestinal parasite, antibacterial, anthelmintic. 

Rubus parvifolius L. Hong Mei Xiao (root, stem) Flavonoids.48 Treat fever, throat pain, blood vomiting, liver and intestinal infections. 

Chen DC, Agopian VG, Avansino JR, I ee JK, Farley SM, Stelzner M. Optical tissue window a novel method for optimizing engraftment of intestinal stem cell organoids. Journal of Surgical Research 2006, 134, 52-60. 

Sandberg, J. W., C. Lau, M. Jacomino, M. Finegold and S. J. Henning (1994). Improving access to intestinal stem-cells as a step toward intestinal gene-transfer. Human Gene Therapy 5(3) 323-329. 

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