Mesothelioma: A tumor derived from mesothelial tissue (peritoneum, pleura, pericardium). It appears as broad sheets of cells, with some regions containing spindle-shaped, sarcoma-like cells and other regions showing adenomatous patterns. Pleural mesotheliomas have been linked to exposure to asbestos. (Dorland, 27th ed)Pleural Neoplasms: Neoplasms of the thin serous membrane that envelopes the lungs and lines the thoracic cavity. Pleural neoplasms are exceedingly rare and are usually not diagnosed until they are advanced because in the early stages they produce no symptoms.Asbestos: Asbestos. Fibrous incombustible mineral composed of magnesium and calcium silicates with or without other elements. It is relatively inert chemically and used in thermal insulation and fireproofing. Inhalation of dust causes asbestosis and later lung and gastrointestinal neoplasms.Peritoneal Neoplasms: Tumors or cancer of the PERITONEUM.Zeolites: Zeolites. A group of crystalline, hydrated alkali-aluminum silicates. They occur naturally in sedimentary and volcanic rocks, altered basalts, ores, and clay deposits. Some 40 known zeolite minerals and a great number of synthetic zeolites are available commercially. (From Merck Index, 11th ed)Asbestosis: A form of pneumoconiosis caused by inhalation of asbestos fibers which elicit potent inflammatory responses in the parenchyma of the lung. The disease is characterized by interstitial fibrosis of the lung, varying from scattered sites to extensive scarring of the alveolar interstitium.Asbestos, Crocidolite: A lavender, acid-resistant asbestos.Mesothelioma, Cystic: A peritoneal mesothelioma affecting mainly young females and producing cysts of variable size and number lined by a single layer of benign mesothelial cells. The disease follows a benign course and is compatible with a normal life expectancy, requiring occasionally partial excision or decompression for relief of pain or other symptoms. Malignant potential is exceptional. (From Holland et al., Cancer Medicine, 3d ed, p1345)Pleura: The thin serous membrane enveloping the lungs (LUNG) and lining the THORACIC CAVITY. Pleura consist of two layers, the inner visceral pleura lying next to the pulmonary parenchyma and the outer parietal pleura. Between the two layers is the PLEURAL CAVITY which contains a thin film of liquid.Pleural Effusion, Malignant: Presence of fluid in the PLEURAL CAVITY as a complication of malignant disease. Malignant pleural effusions often contain actual malignant cells.Asbestos, Amphibole: A class of asbestos that includes silicates of magnesium, iron, calcium, and sodium. The fibers are generally brittle and cannot be spun, but are more resistant to chemicals and heat than ASBESTOS, SERPENTINE. (From Hawley's Condensed Chemical Dictionary, 11th ed)Calbindin 2: A calbindin protein that is differentially expressed in distinct populations of NEURONS throughout the vertebrate and invertebrate NERVOUS SYSTEM, and modulates intrinsic neuronal excitability and influences LONG-TERM POTENTIATION. It is also found in LUNG, TESTIS, OVARY, KIDNEY, and BREAST, and is expressed in many tumor types found in these tissues. It is often used as an immunohistochemical marker for MESOTHELIOMA.Mineral Fibers: Long, pliable, cohesive natural or manufactured filaments of various lengths. They form the structure of some minerals. The medical significance lies in their potential ability to cause various types of PNEUMOCONIOSIS (e.g., ASBESTOSIS) after occupational or environmental exposure. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed, p708)Asbestos, Serpentine: A type of asbestos that occurs in nature as the dihydrate of magnesium silicate. It exists in two forms: antigorite, a plated variety, and chrysotile, a fibrous variety. The latter makes up 95% of all asbestos products. (From Merck Index, 11th ed, p.893)Neoplasms, Mesothelial: Neoplasms composed of tissue of the mesothelium, the layer of flat cells, derived from the mesoderm, which lines the body cavity of the embryo. In the adult it forms the simple squamous epithelium which covers all true serous membranes (peritoneum, pericardium, pleura). The concept does not refer to neoplasms located in these organs. (From Dorland, 27th ed)Epithelioid Cells: Characteristic cells of granulomatous hypersensitivity. They appear as large, flattened cells with increased endoplasmic reticulum. They are believed to be activated macrophages that have differentiated as a result of prolonged antigenic stimulation. Further differentiation or fusion of epithelioid cells is thought to produce multinucleated giant cells (GIANT CELLS).Asbestos, Amosite: Asbestos, grunerite. A monoclinic amphibole form of asbestos having long fibers and a high iron content. It is used in insulation. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Lung Neoplasms: Tumors or cancer of the LUNG.Occupational Exposure: The exposure to potentially harmful chemical, physical, or biological agents that occurs as a result of one's occupation.Occupational Diseases: Diseases caused by factors involved in one's employment.GPI-Linked Proteins: A subclass of lipid-linked proteins that contain a GLYCOSYLPHOSPHATIDYLINOSITOL LINKAGE which holds them to the CELL MEMBRANE.S100 Calcium Binding Protein G: A calbindin protein found in many mammalian tissues, including the UTERUS, PLACENTA, BONE, PITUITARY GLAND, and KIDNEYS. In intestinal ENTEROCYTES it mediates intracellular calcium transport from apical to basolateral membranes via calcium binding at two EF-HAND MOTIFS. Expression is regulated in some tissues by VITAMIN D.Pleural Effusion: Presence of fluid in the pleural cavity resulting from excessive transudation or exudation from the pleural surfaces. It is a sign of disease and not a diagnosis in itself.GuanineGlutamates: Derivatives of GLUTAMIC ACID. Included under this heading are a broad variety of acid forms, salts, esters, and amides that contain the 2-aminopentanedioic acid structure.Tumor Markers, Biological: Molecular products metabolized and secreted by neoplastic tissue and characterized biochemically in cells or body fluids. They are indicators of tumor stage and grade as well as useful for monitoring responses to treatment and predicting recurrence. Many chemical groups are represented including hormones, antigens, amino and nucleic acids, enzymes, polyamines, and specific cell membrane proteins and lipids.Pleural DiseasesPleurisy: INFLAMMATION of PLEURA, the lining of the LUNG. When PARIETAL PLEURA is involved, there is pleuritic CHEST PAIN.Testicular Hydrocele: Accumulation of serous fluid between the layers of membrane (tunica vaginalis) covering the TESTIS in the SCROTUM.Foundations: Organizations established by endowments with provision for future maintenance.Psychology, Applied: The science which utilizes psychologic principles to derive more effective means in dealing with practical problems.Nuclear Warfare: Warfare involving the use of NUCLEAR WEAPONS.Charities: Social welfare organizations with programs designed to assist individuals in need.Research: Critical and exhaustive investigation or experimentation, having for its aim the discovery of new facts and their correct interpretation, the revision of accepted conclusions, theories, or laws in the light of newly discovered facts, or the practical application of such new or revised conclusions, theories, or laws. (Webster, 3d ed)Organizations: Administration and functional structures for the purpose of collectively systematizing activities for a particular goal.Egypt: A country in northern Africa, bordering the Mediterranean Sea, between Libya and the Gaza Strip, and the Red Sea north of Sudan, and includes the Asian Sinai Peninsula Its capital is Cairo.Blogging: Using an INTERNET based personal journal which may consist of reflections, comments, and often hyperlinks.Newspapers: Publications printed and distributed daily, weekly, or at some other regular and usually short interval, containing news, articles of opinion (as editorials and letters), features, advertising, and announcements of current interest. (Webster's 3d ed)BooksEducational Technology: Systematic identification, development, organization, or utilization of educational resources and the management of these processes. It is occasionally used also in a more limited sense to describe the use of equipment-oriented techniques or audiovisual aids in educational settings. (Thesaurus of ERIC Descriptors, December 1993, p132)Lawyers: Persons whose profession is to give legal advice and assistance to clients and represent them in legal matters. (American Heritage Dictionary, 3d ed)Jurisprudence: The science or philosophy of law. Also, the application of the principles of law and justice to health and medicine.Judicial Role: The kind of action or activity proper to the judiciary, particularly its responsibility for decision making.South CarolinaWilliams Syndrome: A disorder caused by hemizygous microdeletion of about 28 genes on chromosome 7q11.23, including the ELASTIN gene. Clinical manifestations include SUPRAVALVULAR AORTIC STENOSIS; MENTAL RETARDATION; elfin facies; impaired visuospatial constructive abilities; and transient HYPERCALCEMIA in infancy. The condition affects both sexes, with onset at birth or in early infancy.Liability, Legal: Accountability and responsibility to another, enforceable by civil or criminal sanctions.Malpractice: Failure of a professional person, a physician or lawyer, to render proper services through reprehensible ignorance or negligence or through criminal intent, especially when injury or loss follows. (Random House Unabridged Dictionary, 2d ed)Physician-Patient Relations: The interactions between physician and patient.Physicians: Individuals licensed to practice medicine.Self-Help Groups: Organizations which provide an environment encouraging social interactions through group activities or individual relationships especially for the purpose of rehabilitating or supporting patients, individuals with common health problems, or the elderly. They include therapeutic social clubs.Feminism: The theory of the political, economic, and social equality of the sexes and organized activity on behalf of women's rights and interests. (Webster New Collegiate Dictionary, 1981)Neoplasms: New abnormal growth of tissue. Malignant neoplasms show a greater degree of anaplasia and have the properties of invasion and metastasis, compared to benign neoplasms.

The European mesothelioma epidemic. (1/1637)

Projections for the period 1995-2029 suggest that the number of men dying from mesothelioma in Western Europe each year will almost double over the next 20 years, from 5000 in 1998 to about 9000 around 2018, and then decline, with a total of about a quarter of a million deaths over the next 35 years. The highest risk will be suffered by men born around 1945-50, of whom about 1 in 150 will die of mesothelioma. Asbestos use in Western Europe remained high until 1980, and substantial quantities are still used in several European countries. These projections are based on the fit of a simple age and birth cohort model to male pleural cancer mortality from 1970 to 1989 for six countries (Britain, France, Germany, Italy, The Netherlands and Switzerland) which together account for three-quarters of the population of Western Europe. The model was tested by comparing observed and predicted numbers of deaths for the period 1990-94. The ratio of mesothelioma to recorded pleural cancer mortality has been 1.6:1 in Britain but was assumed to be 1:1 in other countries.  (+info)

An expert system for the evaluation of historical asbestos exposure as diagnostic criterion in asbestos-related diseases. (2/1637)

Compensation schemes for asbestos-related diseases have developed different strategies for attributing a specific disease to occupational exposure to asbestos in the past. In the absence of quantitative exposure information that allows a valid estimate of an individual's historical exposure, general guidelines are required to retrospectively evaluate asbestos exposure. A risk matrix has been developed that contains qualitative information on the proportion of workers exposed and the level of exposure in particular industries over time. Based on this risk matrix, stepwise decision trees were formulated for decisions regarding the decisive role of historical asbestos exposure in case ascertainment of asbestosis and mesothelioma. Application of decision schemes will serve to speed up the process of verifying compensation claims and also contribute to a uniform decision-making process in legal procedures.  (+info)

A historical cohort mortality study of workers exposed to asbestos in a refitting shipyard. (3/1637)

To investigate the risks of developing asbestos-related diseases we conducted a historical cohort mortality study on 249 ship repair workers (90 laggers and 159 boiler repairers) in a single U.S. Navy shipyard in Japan. We successfully identified the vital status of 87 (96.7%) laggers and 150 (94.3%) boiler repairers, and, of these, 49 (56.3%) and 65 (43.3%) died, respectively, during the follow-up period from 1947 till the end of 1996. Our in-person interviews with some of the subjects clarified that asbestos exposure was considered to be substantially high in the 1950-60s, decreased thereafter gradually but remained till 1979 in the shipyard. The laggers, who had handled asbestos materials directly, showed a significantly elevated SMR of 2.75 (95% C.I.: 1.08-6.48) for lung cancer. The risk developing the disease was greater in the laggers after a 20-year latency (SMR = 3.42). Pancreatic cancer yielded a greater SMR than unity (7.78, 90% C.I.: 2.07-25.19) in a longer working years group. Four laggers died from asbestosis. The boiler repairers, who had many chances for secondary exposure to asbestos and a few for direct exposure, showed no elevation of the SMR of lung cancer overall, but there was a borderline statistically significant SMR of 2.41 (90% C.I.: 1.05-5.45) in a longer working years group. One boiler repairer died from mesothelioma and four from asbestosis.  (+info)

Morphological variations in transplanted tumors developed by inoculation of spontaneous mesothelioma cell lines derived from F344 rats. (4/1637)

Morphological and immunohistochemical features of the abdominal mesotheliomas that were developed by inoculation of 3 cell lines (MeET-4, -5 and -6) established from spontaneous abdominal mesotheliomas in male F344 rats. Although the original tumors of three cell lines showed signs of epithelioid growth with a predominantly simple papillary pattern, transplanted tumors revealed a variety of morphologic features including epithelioid with glandular structures, sarcomatous, and a mixture of these components. All tumor cells of transplanted tumors were positive for alpha-smooth muscle actin (ASMA) but almost negative for desmin as were epithelioid cells of the original tumors, and the cell lines were positive for desmin but not for ASMA. These results suggested that mesothelioma in the F344 rat had the potential for wide spectrum differentiation under in vitro conditions. The microenvironmental factors obtained in vivo can modify their potential ability and their morphological aspects. These factors may be related to tumor cell reexpression of ASMA of tumor cells that were masked under in vitro culture conditions.  (+info)

T-cell receptor transgenic analysis of tumor-specific CD8 and CD4 responses in the eradication of solid tumors. (5/1637)

The role of tumor-specific CD8 and CD4 lymphocytes in rejecting solid tumors has been difficult to determine because of the lack of models in which tumor antigen, specific CD8 cells, and specific CD4 cells can be monitored and controlled. To investigate the minimal components required for the induction and maintenance of CTL activity sufficient to reject a solid tumor in vivo, we transfected the influenza hemagglutinin (HA) gene into a nonimmunogenic class I+/class II- murine malignant mesothelioma (MM) tumor line to generate an endogenous tumor antigen and used TCR transgenic mice with class I- or class II-restricted specificities for HA as sources of naive, tumor-specific T cells. The data show that the presence of a strong tumor antigen is not in itself sufficient to induce an effective CTL response, nor does the presence of a high frequency of precursor cells guarantee tumor rejection. We also show that tumor-specific CD4 cells, when CTL numbers are suboptimal, greatly enhance the eradication of tumor, confirming the importance of antigen-presenting cell presentation of tumor antigens to class II-restricted cells. These data confirm that T-cell receptor transgenic cells, combined with nominal tumor antigen transfection, represent powerful tools to analyze tumor-specific T-cell responses.  (+info)

Photodynamic therapy with mTHPC and polyethylene glycol-derived mTHPC: a comparative study on human tumour xenografts. (6/1637)

The photosensitizing properties of m-tetrahydroxyphenylchlorin (mTHPC) and polyethylene glycol-derivatized mTHPC (pegylated mTHPC) were compared in nude mice bearing human malignant mesothelioma, squamous cell carcinoma and adenocarcinoma xenografts. Laser light (20 J/cm2) at 652 nm was delivered to the tumour (surface irradiance) and to an equal-sized area of the hind leg of the animals after i.p. administration of 0.1 mg/kg body weight mTHPC and an equimolar dose of pegylated mTHPC, respectively. The extent of tumour necrosis and normal tissue injury was assessed by histology. Both mTHPC and pegylated mTHPC catalyse photosensitized necrosis in mesothelioma xenografts at drug-light intervals of 1-4 days. The onset of action of pegylated mTHPC seemed slower but significantly exceeds that of mTHPC by days 3 and 4 with the greatest difference being noted at day 4. Pegylated mTHPC also induced significantly larger photonecrosis than mTHPC in squamous cell xenografts but not in adenocarcinoma at day 4, where mTHPC showed greatest activity. The degree of necrosis induced by pegylated mTHPC was the same for all three xenografts. mTHPC led to necrosis of skin and underlying muscle at a drug-light interval of 1 day but minor histological changes only at drug-light intervals from 2-4 days. In contrast, pegylated mTHPC did not result in histologically detectable changes in normal tissues under the same treatment conditions at any drug-light interval assessed. In this study, pegylated mTHPC had advantages as a photosensitizer compared to mTHPC. Tissue concentrations of mTHPC and pegylated mTHPC were measured by high-performance liquid chromatography in non-irradiated animals 4 days after administration. There was no significant difference in tumour uptake between the two sensitizers in mesothelioma, adenocarcinoma and squamous cell carcinoma xenografts. Tissue concentration measurements were of limited use for predicting photosensitization in this model.  (+info)

Multicentre randomised controlled trial of nursing intervention for breathlessness in patients with lung cancer. (7/1637)

OBJECTIVE: To evaluate the effectiveness of nursing intervention for breathlessness in patients with lung cancer. DESIGN: Patients diagnosed with lung cancer participated in a multicentre randomised controlled trial where they either attended a nursing clinic offering intervention for their breathlessness or received best supportive care. The intervention consisted of a range of strategies combining breathing control, activity pacing, relaxation techniques, and psychosocial support. Best supportive care involved receiving standard management and treatment available for breathlessness, and breathing assessments. Participants completed a range of self assessment questionnaires at baseline, 4 weeks, and 8 weeks. SETTING: Nursing clinics within 6 hospital settings in the United Kingdom. PARTICIPANTS: 119 patients diagnosed with small cell or non-small cell lung cancer or with mesothelioma who had completed first line treatment for their disease and reported breathlessness. OUTCOME MEASURES: Visual analogue scales measuring distress due to breathlessness, breathlessness at best and worst, WHO performance status scale, hospital anxiety and depression scale, and Rotterdam symptom checklist. RESULTS: The intervention group improved significantly at 8 weeks in 5 of the 11 items assessed: breathlessness at best, WHO performance status, levels of depression, and two Rotterdam symptom checklist measures (physical symptom distress and breathlessness) and showed slight improvement in 3 of the remaining 6 items. CONCLUSION: Most patients who completed the study had a poor prognosis, and breathlessness was typically a symptom of their deteriorating condition. Patients who attended nursing clinics and received the breathlessness intervention experienced improvements in breathlessness, performance status, and physical and emotional states relative to control patients.  (+info)

Telomerase activity in human pleural mesothelioma. (8/1637)

BACKGROUND: Gradual telomere erosion eventually limits the replicative life span of somatic cells and is regarded as an ultimate tumour suppressor mechanism, eliminating cells that have accumulated genetic alterations. Telomerase, which has been found in over 85% of human cancers, elongates telomeres and may be required for tumorigenesis by the process of immortalisation. Malignant mesothelioma is an incurable malignancy with a poor prognosis. The disease becomes symptomatic decades after exposure to carcinogenic asbestos fibres, suggesting the long term survival of pre-malignant cell clones. This study investigated the presence of telomerase in pleural malignant mesothelioma, which may be the target for future anti-telomerase drugs. METHODS: Telomerase activity was semiquantitatively measured in extracts from 22 primary pleural mesotheliomas, two benign solitary fibrous tumours of the pleura, four mesothelioma cell lines, and six short term mesothelial cell cultures from normal pleura using a non-isotopic dilution assay of the telomeric repeat amplification protocol. RESULTS: Twenty of the 22 primary mesotheliomas (91%) and all tumour derived mesothelioma cell lines were telomerase positive. Different levels of enzyme activity were observed in the tumours of different histological subtypes. Telomerase activity could not be detected in the six normal mesothelial cell cultures or in the two mesotheliomas. Both benign solitary fibrous tumours showed strong telomerase activity. CONCLUSIONS: Telomerase activity is found in a high proportion of mesotheliomas and anti-telomerase drugs might therefore be useful clinically. The results are consistent with the hypothesis that telomerase activity may be a feature of carcinogenesis in mesotheliomas and possibly in many other cancers.  (+info)

  • A large cohort of people in the western world was accidentally parenterally inoculated with live SV40 through contaminated polio vaccines given between 1959 and 1961, and this might be a factor in the current continuing rise in the incidence of mesothelioma in the United States, Britain and Europe. (
  • The present study investigated the presence of SV40LTAg DNA in recently diagnosed cases of mesothelioma in Britain and the feasibility of detecting the SV40 DNA in archival tissue for retrospective analysis of cases in the peri-vaccination period. (
  • Peritoneal mesothelioma is a relatively rare tumor but highly aggressive malignancy originated in the serosal linings of the peritoneal cavity [ 1 ]. (
  • Cell-matrix interactions are recognized important determinants of tumor growth and invasiveness but the role of the extracellular matrix in mesothelioma is unknown. (
  • This study examined the effect of inhibiting collagen production on mesothelioma cell proliferation in vitro and tumor growth in vivo. (
  • Collagen production by mesothelioma cells was inhibited by incubating cells in vitro with the proline analogue thiaproline (thiazolidine-4-carboxylic acid) or by oral administration of thiaproline in a murine tumor model. (
  • Epigenetic inactivation of tumor suppressor genes is involved in the development of malignant pleural mesothelioma (MPM). (
  • Understanding Mesothelioma Pathology Pathologists study body tissue, fluids, and cells that are surgically removed. (
  • Background - DNA sequences and immunoreactivity associated with Simian virus 40 transforming factors, large T and small T antigens (SV40LTAg), suggestive of an aetiopathogenetic link have been identified in fresh frozen tissue of a high proportion of recent cases of pleural mesotheliomas from the United States, Italy and Germany. (
  • Although the research is still in its early stages, investigators have seen interesting responses to potential new therapies and are optimistic that treatment for mesothelioma can be improved. (