To obtain the best experience, we recommend you use a more up to date browser or turn off compatibility mode in Internet Explorer. In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript. Despite scepticism arising from exaggerated claims about the reprogramming of bone-marrow stem cells, these phenomena do occur on occasion. Long standing examples are the phenomena of transdetermination in Drosophila melanogaster and the types of epithelial metaplasia in which patches of one epithelium are found in the midst of another.
The cause of such events is the alteration of expression of the transcription factors that encode the specification of the tissue types during embryonic development. The alteration can arise from somatic mutation, epigenetic change or change of regulation by an extracellular signal. Metaplasias are associated with tissue damage because the process of regeneration gives small foci of ectopic tissue the opportunity to grow into large patches.
Many metaplasias are understood in molecular detail, and the following are described: transdetermination of leg to wing in D. The nature of the differentiated state, and that of the commitment of undifferentiated stem and progenitor cell populations remains poorly understood, although it is likely that chromatin structure is involved. Therapeutic applications can be imagined in which the expression of relevant transcription factors is modified.
These could potentially be used to inhibit the formation of harmful metaplasias, such as those that predispose individuals to cancer. Transformations from one tissue type to another make up a well established set of phenomena that can be explained by the principles of developmental biology. Although these phenomena might be rare in nature, we can now imagine the possibility of deliberately reprogramming cells from one tissue type to another by manipulating the expression of transcription factors.
This approach could generate new therapies for many human diseases. Raff, M. Adult stem cell plasticity: fact or artifact? Cell and Dev. Wagers, A. Plasticity of adult stem cells. Cell , — Okada, T. Flexibility in Cell Differentiation. Clarendon Press, Oxford, Google Scholar. Rawlins, E.
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An investigation recording all salamanders which can and cannot regenerate a lens from the dorsal iris. Yamada, T. Dysplasia and Metaplasia are essentially two different conditions and not synonymous. Dysplasia is carcinogenic by nature. Unlike in Dysplasia, in case of Metaplasia if the stimulus responsible for the transformation is either done away with or removed, the tissues instantly get back to the normal course of growth and prototype of differentiation.
Dysplasia, or Cervical Dysplasia which is the most common form is often the result of cervical infection caused by the human papillomavirus HPV. This is the particular virus that also causes other conditions like condyloma or genital warts.
The virus is transmitted through sexual acts, during intercourse. Sexual activity with several partners heighten the chances that a woman will get infected with HPV. The virus infects the coating cells of the reproductive tract and the genitals in females. Whereas Metaplasia occurs when healthy cells face severe stress of a physiological and pathological kind. In such a condition the stressed cells start adapting to the changed situations with non-cancerous cellular growths.
Dysplasia is a pathological term used to refer to an irregularity that hinders cell maturation within a particular tissue whereas Metaplasia is the process of the reversible substitution of a distinct kind of cell with another mature cell of the similar distinct kind. Dysplasia is cancerous whereas Metaplasia is non-cancerous. Metaplasia can be stopped by removing the abnormal stimulus, but Dysplasia is a non-reversible process. Cite APA 7 ,.
Difference Between Dysplasia and Metaplasia. Difference Between Similar Terms and Objects. MLA 8 ,. There is an important typo in the second sentence of the fourth paragraph. There is an error above:- Dysplasia LGD is pre-cancerous and is reversible Metaplasia is Non-Cancerous and is more easily reversible than LGD if the irritant cause is removed permanently. Name required. Email required.
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