Basal cells doses

Hofmann, W., Dose Calculations for the Respiratory Tract from Inhaled Natural Radionuclides as a Function of Age - II. Basal Cell Dose Distributions and Associated Lung Cancer Risk, Health Phys. 43 31-44 (1982). 

A layer of epithelium covers the interior of the airway tract. This epithehum contains various cell types such as ciliated, goblet, brush, and basal cells [34]. All cells are in contact with the basement membrane however, basal cells do not reach the airway lumen. Moving through the smaller bronchi and bronchioles toward the respiratory portion, the histological organization of both the epithelium and the underlying lamina propria gradually becomes more simple. 

Interferons (lENs) (52,53), a family of species-specific vertebrate proteins, confer nonspecific resistance to a broad range of viral infections, affect cell proliferation, and modulate immune responses. AH three principal interferons, a-interferon (lEN-a) produced by blood leucocytes, P-interferon (lEN-P) by fibroblasts, and y-interferon (lEN-y) by lymphocytes, also have antiviral activity. The abiUty of interferons to inhibit growth of transplantable and carcinogen-induced tumor led to research showing the direct antiproliferative and indirect immune-mediated antitumor activities (see Chemotherapeutics, anticancer). IENs have been found to be efficacious in certain malignancies and viral infections, eg, hairy cell leukemia (85% response) and basal cell carcinoma (86% response). However, the interferons do have adverse side effects (54). 

Basal cells Stem cells for other airway cell types that do not interface with... 

First, basal cells, which are precursor cells of the other cell types, lie on the basement membrane and do not front the nasal cavity. These cells have desmo-somes and hemidesmosomes, which seem to mediate adhesion between adjacent cells and the basement membrane, respectively. 

Basal cells are polygonal or triangular cells localised immediately above the basement membrane. Usually, they do not reach the free surface of the epithelium. Their cytoplasm is electron-dense. Tono-filaments are arranged in perinuclear array. Golgi complex and endoplasmic reticulum are poorly developed. 

It has been mentioned above that bir-nessite-type samples can show a wide variety of different XRD patterns. Mostly, the samples show only XRD peaks around 240 pm (20 37° for CuKa radiation) and 142 pm (2 ss 66°). These peaks correspond to the (1 0 0) and (110) reflections of the simple hexagonal setting of the S - Mn02 unit cell. Additionally, in some natural as well in synthetic materials the basal plane (0 0 l) reflections (001) and (0 0 2) do occur at about 700 pm (26 312°) and 350 pm (26 25°), respectively. 

Most of the permeases which are insensitive to NCR are synthesized in cells grown on minimal medium containing ammonium ions, without addition of any inducer. However, a few of them do appear to be inducible. For instance, addition to the medium of methionine, leucine valine, isoleucine and alanine, which are taken up by several distinct NCR-insensitive permeases, increases the rate of synthesis of the corresponding permeases [54]. This process involves amplification of a basal rate of permease synthesis rather than all-or-none induction. It has not been studied further at the molecular level. 

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