Mesothelioma is a rare form of cancer that is caused by exposure to asbestos. Cancer cells develop in the mesothelium, a thin layer of tissue that covers the majority of the body’s internal organs. There are four types. Pleural Malignant Mesothelioma (lung), Peritoneal Mesothelioma (abdomen), Percardial Mesothelioma (heart), and Tunica Vaginilas (testicles). One interesting study that examines this disease is called, “An early, nonrandom karyotypic change in immortal Syrian hamster cell lines transformed by asbestos: Trisomy of chromosome 11” - Cancer Genetics and Cytogenetics Volume 22, Issue 3, July 1986, Pages 225-237, by Mitsuo Oshimura, a, Thomas W. Hesterberga and J.Carl Barretta. Here is an excerpt: “Abstract - Cytogenetic studies were performed on eight early passage Syrian hamster embryo cell lines independently derived following asbestos exposure. The modal chromosome number of all the immortal cell lines was near-diploid. At the earliest passage examined, six of eight cell lines had only numerical chromosome changes. Cells in each of these six cell lines had an extra chromosome #11, either as a sole karyotypic change or with other numerical changes. The remaining two cell lines displayed both numerical and structural chromosome changes, but without involvement of chromosome #11. Common abnormalities were -X or -Y, +3, and 8p- in one cell line, and -13 and t(13;21) in the other cell line. A nonrandom gain of chromosome #8 was also found in four cell lines. In three of the four cell lines, trisomy of chromosome #8 seems to have occurred during karyotypic progression. The observation that nonrandom changes in chromosome number are an early karyotypic change after carcinogen treatment supports our hypothesis that induction of aneuploidy by asbestos is mechanistically important in the transformation of Syrian hamster embryo cells in culture and, further, suggests that trisomy 11 plays a major role in the early steps of immortalization and neoplastic progression.”
A second study is called, “The HL-A system in asbestos workers” by J A Merchant, P T Klouda, C A Soutar, W R Parkes, S D Lawler, M Turner-Warwick - Br Med J 1975;1:189-191 (25 January). Here is an excerpt: “In a study of the HL-A system in 56 selected asbestos workers referred to the Pneumoconiosis Medical Panel with definite or suspected asbestosis, the W 27 antigen was found more often than among a control population. Six of the 10 asbestos workers with the W 27 antigen had definite radiographic evidence of asbestosis compared to 13 out of 46 without the W 27 antigen. These observations, if confirmed, suggest that the W 27 antigen may provide a useful marker of an enhanced susceptibility to the tissue-damaging effects of asbestos dust.”
A third study is called, “Mortality among long-term employees of an Ontario asbestos-cement factory.” by M M Finkelstein Br J Ind Med 1983;40:138-144. Here is an excerpt: “Abstract - Mortality was studied among a group of 328 employees of an Ontario asbestos-cement factory who had been hired before 1960 and who had been employed for a minimum of nine years. The group of 87 men who had worked in the rock wool/fibre glass operations, or who had been otherwise minimally exposed to asbestos, had mortality rates similar to those of the general Ontario population, while the group of asbestos-exposed employees had all-cause mortality rates double those of the Ontario population, mortality rates due to malignancies five times higher than expected, and deaths attributed to lung cancer eight times more frequent than expected. According to the best evidence available, 10 of 58 deaths among the production workers were due to malignant mesothelioma and 20 to lung cancer. The men dying of mesothelioma were younger than the men dying of lung cancer with mean ages at death of 51 and 64 years respectively. An exposure model was constructed on the basis of the available air sampling data, and individual exposure histories were calculated. These exposure histories were used to investigate the exposure-response relationships for asbestos-associated malignancies.”
If you found any of these studies interesting, please read them in their entirety. We all owe a great deal of thanks to the people who are researching these important issues.
Source: By.Monty Wrobleski http://www.nephrogenicsystemicfibrosislawsuit.com/
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