Increased Cellular Density in the Presence of Asbestos Fibers

1985 ◽  
pp. 533-538
Author(s):  
M. Pagé ◽  
L. Dumas
Author(s):  
Charles L. Sanders ◽  
Roy R. Adee

Asbestos is a generic name for a group of hydrated mineral silicates that occur naturally in a fibrous form. The early interactions of asbestos fibers with alveolar cells in large part determines their long-term toxicity. Young adult, SPF, Fischer rats were given a single intratracheal instillation of 2 mg crocidolite asbestos suspended in 0.5 ml of 0.9% NaCl solution. About 80% of the fibers had lengths of less than 10 ym as measured on light micrographs of the fiber suspension. Two rats were killed at 3 hr, 1 d and 1, 4, 8, 12 and 16 wk after instillation and the lungs instilled with 8 ml McDowell - Trumps at 20 cm H2O. Lung tissue was dehydrated and sputtered coated with palladium-gold for SEM or post-fixed in osmium tetroxide, embedded in epoxy resin and sections stained with uranyl acetate and lead citrate for TEM.


Author(s):  
R. E. Heffelfinger ◽  
C. W. Melton ◽  
D. L. Kiefer ◽  
W. M. Henry ◽  
R. J. Thompson

A methodology has been developed and demonstrated which is capable of determining total amounts of asbestos fibers and fibrils in air ranging from as low as fractional nanograms per cubic meter (ng/m3) of air to several micrograms/m3. The method involves the collection of samples on an absolute filter and provides an unequivocal identification and quantification of the total asbestos contents including fibrils in the collected samples.The developed method depends on the trituration under controlled conditions to reduce the fibers to fibrils, separation of the asbestos fibrils from other collected air particulates (beneficiation), and the use of transmission microscopy for identification and quantification. Its validity has been tested by comparative analyses by neutron activation techniques. It can supply the data needed to set emissions criteria and to serve as a basis for assessing the potential hazard for asbestos pollution to the populace.


Author(s):  
J. D. Shelburne ◽  
Peter Ingram ◽  
Victor L. Roggli ◽  
Ann LeFurgey

At present most medical microprobe analysis is conducted on insoluble particulates such as asbestos fibers in lung tissue. Cryotechniques are not necessary for this type of specimen. Insoluble particulates can be processed conventionally. Nevertheless, it is important to emphasize that conventional processing is unacceptable for specimens in which electrolyte distributions in tissues are sought. It is necessary to flash-freeze in order to preserve the integrity of electrolyte distributions at the subcellular and cellular level. Ideally, biopsies should be flash-frozen in the operating room rather than being frozen several minutes later in a histology laboratory. Electrolytes will move during such a long delay. While flammable cryogens such as propane obviously cannot be used in an operating room, liquid nitrogen-cooled slam-freezing devices or guns may be permitted, and are the best way to achieve an artifact-free, accurate tissue sample which truly reflects the in vivo state. Unfortunately, the importance of cryofixation is often not understood. Investigators bring tissue samples fixed in glutaraldehyde to a microprobe laboratory with a request for microprobe analysis for electrolytes.


Author(s):  
J. R. Millette ◽  
R. S. Brown

The United States Environmental Protection Agency (EPA) has labeled as “friable” those building materials that are likely to readily release fibers. Friable materials when dry, can easily be crumbled, pulverized, or reduced to powder using hand pressure. Other asbestos containing building materials (ACBM) where the asbestos fibers are in a matrix of cement or bituminous or resinous binders are considered non-friable. However, when subjected to sanding, grinding, cutting or other forms of abrasion, these non-friable materials are to be treated as friable asbestos material. There has been a hypothesis that all raw asbestos fibers are encapsulated in solvents and binders and are not released as individual fibers if the material is cut or abraded. Examination of a number of different types of non-friable materials under the SEM show that after cutting or abrasion, tuffs or bundles of fibers are evident on the surfaces of the materials. When these tuffs or bundles are examined, they are shown to contain asbestos fibers which are free from binder material. These free fibers may be released into the air upon further cutting or abrasion.


Author(s):  
E. V. Kovalevskiy ◽  
S. V. Kashanskiy ◽  
I. M. Tskhomariia

One of the malignant neoplasms, which is associated with exposure to only one factor - asbestos fibers, is malignant mesothelioma. At the same time, today there is already convincing evidence of its polyetiology. This indicates the urgent need to expand research in this direction in order to develop targeted preventive measures.


Author(s):  
Caterina Ledda ◽  
Claudia Lombardo ◽  
Elisabetta A. Tendi ◽  
Maria Hagnas ◽  
Gianluca Paravizzini ◽  
...  

: Fluoro-edenite (FE) is an asbestos-like amphibole present in the bentonitic lavas extracted from a stone quarry in Biancavilla, a village sited in the Etnean Volcanic Area (Italy). : Thoracic pathologies are the results of excessive inflammatory processes that are the early response of the immune system to inhaled fibers. As demonstrated for asbestos, fibers may trigger immune system cells in an acute and/or chronic manner. This review aims to clarify the pathways of inflammation in workers exposed to FE fibers. : Based on the articles reviewed, it seems that a permanent stimulus created by repeatedly inhaling the FE fibers and their persistence in the body can act as trigger both in promoting inflammatory processes and in immunological induction of autoimmune disease.


1994 ◽  
Vol 102 ◽  
pp. 253 ◽  
Author(s):  
A. Tossavainen ◽  
A. Karjalainen ◽  
P. J. Karhunen
Keyword(s):  

2010 ◽  
Vol 2010 ◽  
pp. 1-6 ◽  
Author(s):  
Roka Namoto Matsubayashi ◽  
Teruhiko Fujii ◽  
Kotaro Yasumori ◽  
Toru Muranaka ◽  
Seiya Momosaki

Purpose. To investigate the correlation of Apperent Diffusion Coefficient (ADC) values in invasive ductal breast carcinomas with detailed histologic features and enhancement ratios on dynamic contrast-enhanced MRI.Methods and Materials. Dynamic MR images and diffusion-weighted images (DWIs) of invasive ductal breast carcinomas were reviewed in 25 (26 lesions) women. In each patient, DWI, T2WI, T1WI, and dynamic images were obtained. The ADC values of the 26 carcinomas were calculated with b-factors of 0 and 1000 s/ using echoplanar DWI. Correlations of the ADC values were examined on dynamic MRI with enhancement ratios (early to delayed phase: E/D ratio) and detailed histologic findings for each lesion, including cellular density, the size of cancer nests, and architectural features of the stroma (broad, narrow, and delicate) between cancer nests.Results. The mean ADC was  /sec. Cellular density was significantly correlated with ADC values () and E/D ratios (). The ADC values were also significantly correlated to features of the stroma (broad to narrow, ).Conclusion. The findings suggest that DWIs reflect the growth patterns of carcinomas, including cellular density and architectural features of the stroma, and E/D ratios may also be closely correlated to cellular density.


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