FACTOID # 24: Looking for table makers? Head to Mississippi, with an overwhlemingly large number of employees in furniture manufacturing.
 Home   Encyclopedia   Statistics   States A-Z   Flags   Maps   FAQ   About 


FACTS & STATISTICS    Advanced view

Search encyclopedia, statistics and forums:



(* = Graphable)



Encyclopedia > Metaplasia

Metaplasia is the replacement of one differentiated cell type with another differentiated cell type. An example is the condition synovial chondromatosis where cells of the synovial membrane undergo metaplasia to become cartilage-producing chondrocytes. Metaplasia is not synonymous with dysplasia and is not considered carcinogenesis. A cell type is a distinct morphological or functional form of cell. ... Please wikify (format) this article or section as suggested in the Guide to layout and the Manual of Style. ... The synovium or synovial membrane is a thin, weak layer of tissue which lines the non-cartilaginous surfaces within the joint space, sealing it from the surrounding tissue. ... Cartilage is a type of dense connective tissue. ... Chondrocytes are the cells of cartilage. ... Dysplasia (latin for bad form) is an abnormality in the appearance of cells indicative of an early step towards transformation into a neoplasia. ... In pathology, a carcinogen is any substance or agent that promotes cancer. ...

Metaplasia causes precursor cells to change their cell fate, and does not change existing differentiated cells.

Metaplasia is reversible and usually occurs in response to chronic irritation and inflammation and allows for substitution of cells that are better able to survive under circumstances in which a more fragile cell type might succumb. Usually harmless in itself, metaplasia can affect the lining of various organs, such as the bronchi (airways) and bladder. Metaplasia of the cerrvix, which occurs in cervical erosion, can be detected by a cervical smear test. Cervical erosion is a partial or complete absence of the squamous epithelium of the cervix. ... In gynecology, the Papanikolaou test (also called Pap smear, Pap test, cervical smear, or smear test) is a medical screening method for detecting infectious, premalignant, and malignant processes in the ectocervix, endocervix and endometrium. ...

The medical significance of metaplasia, is that cells may progress from metaplasia, to develop dysplasia, and then cancer. This occurs in many sites in the body, including the bladder, cervix, and in Barrett's oesophagus. Thus where metaplasia is detected at these sites, efforts are made to reverse the causative irritant, to decrease the risk of progression to malignancy. In addition, the metaplastic area must be carefully monitored to ensure that dysplasia is minimal. A progression to significant dysplasia indicates that the area could need removal to prevent the development of cancer.



  • The AMA Home Medical Encyclopedia, Random House, p.683

  Results from FactBites:
Holistic Health Encyclopedia - L (6915 words)
Its histogenesis may be related to chronic inflammation and injury of the bronchial epithelium, which leads to replacement of the normal ciliated columnar epithelium by a squamous epithelium.
This transformation from a glandular epithelium to squamous epithelium is known as squamous metaplasia.
These changes are followed by a squamous metaplasia.
  More results at FactBites »



Share your thoughts, questions and commentary here
Your name
Your comments

Want to know more?
Search encyclopedia, statistics and forums:


Press Releases |  Feeds | Contact
The Wikipedia article included on this page is licensed under the GFDL.
Images may be subject to relevant owners' copyright.
All other elements are (c) copyright NationMaster.com 2003-5. All Rights Reserved.
Usage implies agreement with terms, 1022, m