Tissues mitotic activity

Smooth muscles do more than contract and the regulation of the mitotic activity of vascular smooth muscle is important in the maintenance of the oxygen supply to tissues and the genesis of hypertension of non-renal origin. Secretion activities of smooth muscle are just beginning to be appreciated. 

Fetner has also demonstrated chromatid breaks in a human tissue-culture cell line exposed to ozone at 8 ppm for 5 min. Other tissue-culture studies include that of Sachsenmaier et who noted tetraploidy and other chromosomal abnormalities in embryonic chick fibroblasts exposed to ozone and a decrease in transplantability of mouse ascites tumor cells. In addition, Pace et demonstrated an interference by ozone with mitotic activity in two tissue-culture cell lines. More recently, Booher et al. reported that lung cells exposed in culture to ozone concentrations as low as 0.3 ppm demonstrated an inhibition in growth that was proportional to the ozone concentration. 

Mechanism of Action A topical corticosteroid that inhibits accumulation of inflammatory cells at inflammation sites, suppresses mitotic activity, and causes vasoconstriction. Therapeutic Effect Decreases or prevents tissue response to inflammatory process. 

Clinical pharmacology Erythropoietin is instrumental in the production of red cells from the erythroid tissues in the bone marrow. The majority of this hormone is produced in the kidney in response to hypoxia, with an additional 10% to 15% of synthesis occurring in the hver. Erythropoietin functions as a growth factor, stimulating the mitotic activity of the erythroid progenitor cells and early precursor cells. Chronic renal failure patients often manifest the sequelae of renal dysfunction, including anemia. Anemia in cancer patients may be related to the disease itself or the effect of concomitantly administered chemotherapeutic agents. 

E. 5-cm. shoot collected and 1000 micron wide column of pith tissue examined. Since pith tissue was frequently ruptured, mitotic figures recorded represent only a fraction of those present. Moreover pith tissue is considerably less active than the more peripheral tissues, indicating that total subapical mitotic activity in growing bamboo shoots may attain extraordinar) proportions. 

A solitary fibrous tumour was first described in pleural tissue by P. Klemperer et al. in 1931. Meanwhile, this rare entity has been reported in various organs, with the liver being affected in 26 cases. The tumour shows cellular areas (consisting of bundles of spindle cells arrayed haphazardly or in a storiform pattern) and relatively acellular areas (containing abundant collagen bundles). There is evidence of cellular atypia, mitotic activity and ectatic vessels. This tumour possesses malignant potential with the ability to metastazise. (134)... 

B44. Bullough, W. S., The control of mitotic activity in adult mammalian tissues. Biol. Rev. Cambridge Phil. Soc. 37, 307 (1962). 

Epithelioid features are known to occur in smooth muscle tumors, usually as a focal finding but occasionally as the predominant pattern. Such tumors have previously been designated as leiomyoblastomas, but current information indicates that even relatively bland tumors in the soft tissue may have metastatic potential. Thus, the term epithelioid LMS is preferred for those lesions with any degree of mitotic activity and cellular atypia. 

An inflammatory myofibroblastic tumor (IMT) of the bladder may arise either spontaneously or as a result of a prior instrumentation of the bladder. IMTs are benign mesenchymal neoplasms composed of a proliferation of relatively monotonous myofibroblastic cells (typical tissue culture appearance) in a richly vascularized background with red blood cell extravasation and lym-phoplasmacytic inflammatory infiltrate. Mitotic activity ranges from absent to brisk. Abnormal mitotic figures... 

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