Critical colonization

Critical colonization multiplication of bacteria causing a delay in wound healing, usually associated with an exacerbation of pain but with no overt host reaction. 

Ribeiro, A. J., Neufeld, R. Arnaud, P. Chaumeil, J. C. (1999). Microencapsulation of lipophilic drugs in chitosan-coated alginate microspheres. International Journal of Pharmaceutics, Vol. 187,1, (September 1999), pp. (115-123), ISSN 0378-5173 Rubinstein, A. (1995). Approaches and opportunities in colon-specific drug-delivery. Critical Reviews in Therapeutic Drug Carrier Systems, Vol 12, 2-3,1995), pp. (101-149), ISSN 0743-4863... 

The critical first step in the acquisition of acute bacterial meningitis is nasopharyngeal colonization of the host by the bacterial pathogen. The bacteria first attach themselves to nasopharyngeal epithelial cells and are then phagocytized into the host s bloodstream. 

From this description it is clear that this new cell is a highly specialized feature and this rises an interesting question of what was the primary reason for development of such a cell in the fish, where bones are not resorbed and colonized by the hematopoiesis. There is no experimental answer to this question yet, but speculation on that subject should concentrate on other requirements for bone resorption that would be of an immediate necessity for the fish. Such other requirement is tooth eruption. Without teeth fish would be unable to eat most of the food available, and to defend itself, so their eruption is of critical importance for survival. With emergence of calcification of bones during their development teeth had it increasingly more difficult to erupt and this required development of mechanism to assist in this process. So the hypothesis based on this speculation is, that the osteoclasts emerged primarily to assist tooth eruption. 

The role of transferring water by lignin makes the ability to produce lignin critical to any plants survival and permits even primitive plants to colonize dry land. 

Gravitt KR, Ward NE, Fan D, Skibber JM, Levin B, O Brian CA (1994) Evidence that protein kinase C-alpha activation is a critical event in phorbol ester-induced multiple drug resistance in human colon cancer cells. Biochem Pharmacol 48 375-381... 

Proteus mirabilis bacteria was dispersed in agar before solidifying into a Petri dish, and colonization occurred which seems contradictory for an aerobic microorganism, but is understandable considering the gel structure is permeable to air, water vapor, and nutrients. The previous observation is further reason not to constmct a barrier dressing from an aqueous gel, hydrogel or other similar material containing more than about 20% water where protection from bacteria is a critical requirement. 

Recently L. Hovgaard and H. Brpndsted published a critical review in which they stated that polysaccharides appear as promising compounds for use in developing colon-specific drug delivery systems [66],... 

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