Effect of size of man-made and natural mineral fibers on chemiluminescent response in human monocyte-derived macrophages. (Articles).
Fiber size is an important factor in the tumorigenicity of various mineral fibers and asbestos fibers Asbestos fibers are released from asbestos containing materials (ACMs). Friable asbestos containing materials release fibers more readily than encapsulated asbestos containing materials. in animal experiments. We examined the time course of the ability to induce lucigenin-dependent chemiluminescence chemiluminescence /chemi·lu·mi·nes·cence/ (kem?i-loo?mi-nes´ens) luminescence produced by direct transformation of chemical energy into light energy. (CL) from human monocyte-derived macrophages Macrophages
White blood cells whose job is to destroy invading microorganisms. Listeria monocytogenes avoids being killed and can multiply within the macrophage. exposed to Japan Fibrous Material standard reference samples (glass wool glass wool
Fine-spun fibers of glass used especially for insulation and in air filters.
Noun 1. glass wool - glass fibers spun and massed into bundles resembling wool , rock wool rock wool
See mineral wool.
Noun 1. rock wool - a light fibrous material used as an insulator
mineral wool , micro glass fiber, two types of refractory ceramic fiber, refractory mullite fiber, potassium titanium whisker, silicon carbide silicon carbide, chemical compound, SiC, that forms extremely hard, dark, iridescent crystals that are insoluble in water and other common solvents. Widely used as an abrasive, it is marketed under such familiar trade names as Carborundum and Crystolon. whisker, titanium oxide whisker, and wollastonite wol·las·ton·ite
A white to gray mineral, essentially CaSiO3, found in metamorphic rocks and used in ceramics, paints, plastics, and cements.
[After William Hyde Wollaston. ). We determined how fiber length or width might modify the response of cells. We found that the patterns of time-dependent increase of CL (sigmoid sigmoid /sig·moid/ (sig´moid)
1. shaped like the letter C or S.
2. sigmoid colon.
sig·moid or sig·moi·dal
1. Having the shape of the letter S. type) were similar for each sample except wollastonite. We observed a strong correlation between geometric-mean length and ability to induce CL in seven samples > 6 [micro]m in length over the time course (largest [r.sup.2] = 0.9760). Although we also observed a close positive correlation Noun 1. positive correlation - a correlation in which large values of one variable are associated with large values of the other and small with small; the correlation coefficient is between 0 and +1
direct correlation between geometric-mean width and the ability to induce CL in eight samples < 1.8 [micro]m in width at 15 min ([r.sup.2] = 0.8760), a sample of 2.4 [micro]m in width had a low ability to induce CL. Moreover, the relationship between width and the rate of increase in ability to induce CL had a negative correlation Noun 1. negative correlation - a correlation in which large values of one variable are associated with small values of the other; the correlation coefficient is between 0 and -1
indirect correlation at 30-60 min (largest [r.sup.2] = 0.7473). Our findings suggest that the release of superoxide superoxide /su·per·ox·ide/ (-ok´sid) any compound containing the highly reactive and extremely toxic oxygen radical O2-, a common intermediate in numerous biological oxidations.
n. from macrophages occurs nonspecifically for various types of mineral fibers depending on fiber length. Key words: fiber length, glass wool, macrophage macrophage /mac·ro·phage/ (mak´ro-faj) any of the large, mononuclear, highly phagocytic cells derived from monocytes that occur in the walls of blood vessels (adventitial cells) and in loose connective tissue (histiocytes, phagocytic , man-made mineral fibers, micro glass fiber, reactive oxygen species reactive oxygen species,
n molecules and ions of oxygen that have an unpaired electron, thus rendering them extremely reactive. Many cellular structures are susceptible to attack by ROS contributing to cancer, heart disease, and cerebrovascular disease. , refractory ceramic fiber, rock wool, silicon carbide whisker, superoxide. Environ Health Perspect 109:1033-1038 (2001). [Online 27 September 2001]
Exposure to amphibole asbestos is associated with the development of mesotheliomas, lung cancers, and fibrotic lung diseases (1,2). Therefore, man-made and natural mineral fibers often have been substituted for asbestos. Although numerous inhalation studies demonstrated no significant increase in tumor incidence in animals exposed to such substitutes (3-5), several mineral fibers (refractory ceramic fiber and fiber glass) were carcinogenic carcinogenic
having a capacity for carcinogenesis. in rodent chronic inhalation studies (6,7). Morover, in animal intraperitoneal studies, the fiber length of asbestos and other mineral fibers has been found to be one of the major descriptors of tumorigenicity (8-10). Therefore, we considered that the extensive khowledge on asbestos may apply to other mineral fibers' tumorigenicity.
The concept that reactive oxygen species (ROS ROS,
n.pr See reactive oxygen species. ) such as hydrogen peroxide hydrogen peroxide, chemical compound, H2O2, a colorless, syrupy liquid that is a strong oxidizing agent and, in water solution, a weak acid. It is miscible with cold water and is soluble in alcohol and ether. , superoxide, and the hydroxyl radical may underlie the pathogenesis of derangement de·range·ment
1. Disturbance of the regular order or arrangement of parts in a system.
2. Mental disorder; insanity.
de·range has become the focus of extensive research in asbestos fibers (11). Reactive oxygen species, especially the hydroxyl radical, can alter biologic macromolecules Macromolecules
A large molecule composed of thousands of atoms.
Mentioned in: Gene Therapy
macromolecules including proteins, cell membrane Cell membrane
The membrane that surrounds the cytoplasm of a cell; it is also called the plasma membrane or, in a more general sense, a unit membrane. This is a very thin, semifluid, sheetlike structure made of four continuous monolayers of molecules. lipids, DNA DNA: see nucleic acid.
or deoxyribonucleic acid
One of two types of nucleic acid (the other is RNA); a complex organic compound found in all living cells and many viruses. It is the chemical substance of genes. , and RNA RNA: see nucleic acid.
in full ribonucleic acid
One of the two main types of nucleic acid (the other being DNA), which functions in cellular protein synthesis in all living cells and replaces DNA as the carrier of genetic , causing cellular dysfunction, cytotoxicity cytotoxicity /cy·to·tox·ic·i·ty/ (si?to-tok-sis´i-te) the degree to which an agent possesses a specific destructive action on certain cells or the possession of such action. , and possibly malignant transformation malignant transformation Oncology The constellation of changes in the growth properties of cells in culture evoked by various agents–eg, radiation, toxins, and viruses that result in development of tumors from asbestos fibers (11-13).
However, hydroxyl radical activity differs among three tumorigenic tu·mor·i·gen·ic
Capable of causing tumors. fibers: amosite amosite
Variety of the silicate mineral cummingtonite, which is a source of asbestos. Cummingtonite is an amphibole mineral, an iron and magnesium silicate that occurs in metamorphic rocks in the form of long needlelike, fibrous crystals. asbestos, silicon carbide, and refractory ceramic fiber (RCF RCF Remote Call Forwarding
RCF Residential Care Facility
RCF Relative Centrifugal Force
RCF Rolling Contact Fatigue
RCF Refractory Ceramic Fiber
RCF Revolving Credit Facility
RCF Rock Characterisation Facility
RCF Registration Confirm
RCF Retained Cash Flow ). Amosite and RCF release hydroxyl radicals, whereas silicon carbide fibers have no hydroxyl radical activity (13). Therefore, although hydroxyl radical activity may increase the tumorigenicity of mineral fibers it is not necessary for it to occur. Moreover, the results from numerous intrapleural studies led to the conclusion that basically all types of elongated e·lon·gate
tr. & intr.v. e·lon·gat·ed, e·lon·gat·ing, e·lon·gates
To make or grow longer.
adj. or elongated
1. Made longer; extended.
2. Having more length than width; slender. dust particles can induce tumors if they are sufficiently long, thin, and durable in the tissue (5,8,10,15). Our study focuses on the superoxide induced in asbestos or other mineral fibers, and on the relationship between the ability to induce superoxide and the fiber size of various mineral fibers.
Long asbestos fibers, such as chrysotile chrysotile: see serpentine.
Fibrous variety of the magnesium silicate mineral serpentine; it is the most important asbestos mineral. Individual fibres are white and silky, but the aggregate in veins is usually green or yellowish. and amosite, are more effective than short fibers in eliciting the release of superoxide from macrophages (16). Among various mineral particles, fibrous dust causes a significant increase in the release of superoxide from macrophages (11,17), whereas nonfibrous particles were less active in this regard (18). However, only a few studies have examined in detail the relationship between length and release of superoxide with manmade mineral fibers (19,20). Moreover, it was suggested that fiber length is not an important factor in the ability of man-made mineral fibers to induce production of reactive oxygen species in polymorphonuclear leukocytes polymorphonuclear leukocytes (pol´ēmôr´fōnoo´klēr loo´kō-sīts),
We demonstrated previously a method for comparing the ability to induce lucigenin-dependent chemiluminescence (CL) per fiber from human monocyte-derived macrophages exposed to nine types of mineral fibers of different sizes at the acute phase of the response (20). We observed that the ability to induce CL increased with fiber length at the acute phase of the response, when the mineral fibers were longer than approximately 6 [micro]m. Our purpose in this study was to investigate the time course of the relationship between fiber length and the ability to induce CL, and to determine how fiber width might modify this response with various mineral fibers.
Materials and Methods
Mineral fibers. We used the Japan Fibrous Material (JFM JFM Journal of Fluid Mechanics
JFM Just for Me
JFM Japan Finance Corporation for Municipal Enterprises
JFM Joint Forces Memorandum
JFM Joint Frequency Management
JFM Just Fine Magic (slang, polite form; explains unexplainable processes) ) standard reference samples provided by the Japan Fibrous Material Research Association (21), designated by geometric-mean length (micrometers), geometric-mean width (micrometers), and number of fibers per unit weight (micrograms): glass wool (GW1, 20.0 [micro]m; 0.88 [micro]m; 0.7 x [10.sup.3]/[micro]g); rock wool (RW1, 16.5, 1.8, 1.7); micro glass fiber (MG1, 3.0, 0.24, 65); refractory ceramic fiber (RF1, 12.0, 0.77, 8.8; RF2, 11.0, 1.1, 8.7); refractory mullite fiber (RF3, 11.0, 2.4, 3.5); potassium titanium whisker (PT1, 6.0, 0.35, 590); silicon carbide whisker (SC1, 6.4, 0.30, 410); titanium oxide whisker (TO1, 2.1, 1.00, 640); and wollastonite (WO1, 10.5, 1.00, 24). The characterization of these fibers has been documented elsewhere (21,22). For example, chemical composition of these fibers has been demonstrated by X-ray fluorescence analysis. [Fe.sub.2][0.sub.3] is the only iron compound which was detected in all samples (chemical composition of [Fe.sub.2][0.sub.3], by percentage: GW1, 0.28; RW1, 0.41; MG1, 0.07; RF1, 0.15; RF2, 0.04; RF3, 0.05; PT1, 0.02; SC1, 0.07; TO1, 0.04; and WO1, 0.30). Each sample was dried and heat-sterilized at 80 [degrees] C for 48 hr and suspended in fetal bovine serum Fetal bovine serum ( or foetal bovine serum) is serum taken from the fetuses of cows. Fetal Bovine Serum (or FBS) is the most widely used serum in the culturing of cells. In some papers the expression foetal calf serum is used. (FBS FBS
fasting blood sugar
FBS Fasting blood sugar. See Fasting glucose. ) at a concentration of 1 mg/mL. The suspensions were incubated for 15 min at 37 [degrees] C, and spin-washed three times in Hanks' balanced salt solution (HBSS HBSS Hank's Balanced Salt Solution
HBSS Hanks' Buffered Salt Solution
HBSS High Band Sub-System
HBSS Host-Based Security System
HBSS Hill Billy Snap Shooter (Joe Clark photography book) ), at 900g for 20 min. Pellets were resuspended at stepped suspension concentrations from 10/13 mg/mL to 10 mg/mL, except SC1, which was adjusted to one-tenth the concentration of other samples. These suspensions were stored at 4 [degrees] C.
Cell isolation. We obtained heparinized blood from healthy donors by venipuncture venipuncture /veni·punc·ture/ (ven?i-pungk´chur) surgical puncture of a vein.
ve·ni·punc·ture or ve·ne·punc·ture
n. and diluted it 1:1 in HBSS. We isolated monocyte-lymphocyte fractions by Ficoll density centrifugation Centrifugation
A mechanical method of separating immiscible liquids or solids from liquids by the application of centrifugal force. This force can be very great, and separations which proceed slowly by gravity can be speeded up enormously in centrifugal and plated them in 9-cm-diameter plastic tissue culture dishes for monocyte monocyte /mono·cyte/ (mon´o-sit) a mononuclear, phagocytic leukocyte, 13µ to 25µ in diameter, with an ovoid or kidney-shaped nucleus, and azurophilic cytoplasmic granules. adherence (23). We cultured the adhering cells for 9 days in RPM11640 HEPES HEPES N-2-Hydroxyethylpiperazine-N'-2-Ethanesulfonic Acid modification (Sigma Chemical Co., St. Louis, MO, USA) with 10% FBS, 100 U/mL penicillin, and 100 [micro]g/mL streptomycin streptomycin (strĕp'tōmī`sĭn), antibiotic produced by soil bacteria of the genus Streptomyces and active against both gram-positive and gram-negative bacteria (see Gram's stain), including species resistant to other . This culture medium was changed every 2 days. Adherent adherent /ad·her·ent/ (-ent) sticking or holding fast, or having such qualities. cells were separated after 6 days, and suspended in serum-free RPMI RPMI Rapid Prototyping & Manufacturing Institute
RPMI Roswell Park Memorial Institute
RPMI Royal Park Memorial Institute (culture medium) 1640.
Chemiluminescence measurements. The method of measurement of lucigenin-dependent CL from 6-day-old human monocyte-derived macrophages exposed to various mineral fibers has been described (24): The lucigenin responses increased with the increasing age of cultures over 6 days, and Nyberg and Klockars (24) obtained a correlation between lucigenin-dependent CL and superoxide production measured with the cytochrome C reduction assay at 6 days of culture.
The isolated cells (1 x [10.sup.5] cells) were transferred into a luminometer tube containing mineral sample suspension (65 [micro]L, 10% FBS, 0.1 mM lucigenin, and in some experiments 1,000 U/mL superoxide dismutase superoxide dismutase
An enzyme that catalyzes the decomposition of a superoxide into hydrogen peroxide and oxygen.
superoxide dismutase (SOD). The final volume of each tube was 1 mL. The light emission of each sample was detected at 15-min intervals with a luminescence luminescence, general term applied to all forms of cool light, i.e., light emitted by sources other than a hot, incandescent body, such as a black body radiator. reader (ALOKA BLR-201; Mitaka, Tokyo, Japan). We measured all samples including the negative control (no fiber) with the same cell suspension at 10-sec intervals. We performed all reactions at 37 [degrees] C in RPMI 1640, each measurement 4 times.
Statistical analysis. We analyzed the ability to induce CL per fiber of each sample as described previously (20). Briefly, we examined the relation between the estimated number of fibers administered and CL response by linear regression Linear regression
A statistical technique for fitting a straight line to a set of data points. . The slope ([[beta].sub.1]) of the regression line was taken as a measure of the ability to induce CL per fiber. We excluded the data of [[beta.sub.1] for [r.sup.2] < 0.9. We also examined the relation between fiber size and ability to induce CL by linear regression, and calculated the increase in the rate of induction with two [[beta].sub.1]. We examined the time course of the increase in the ability to induce CL by power regression. Finally, we examined the relation between fiber size and increased ability to induce CL using linear regression.
The time course of the ability to induce CL per fiber ([[beta].sub.1]). We tested the CL response of all JFM preparations and controls at constant rotation every 15 min by using a stock of cells in suspension. We needed [[beta].sub.1] to compare the CL response of each sample at a value not related to the number of fibers administered. Table 1 shows [[beta].sub.1] and [r.sup.2]. All fiber samples except for WO1 induced a CL response in a dose-dependent manner. Each response was almost completely inhibited by SOD, which is a superoxide scavenger (data not shown). WO1 was excluded in subsequent analyses because its CL response increased rectilinearly and the linearity of its dose response was low (Table 1). Moreover, we also excluded the [[beta].sub.1] data for [r.sup.2] < 0.9 at each measurement time.
As shown in Figure 1, each JFM standard reference sample produced a sigmoid-type increase in [[beta].sub.1]. The pattern of increase in [[beta].sub.1] for each sample was similar, although the values differed.
[FIGURE 1 OMITTED]
The similarity of the increase in [[beta].sub.1] to JFM samples. We calculated the rate of increase in [[beta].sub.1] to demonstrate the similarity of the response pattern to various mineral fibers. Table 2 shows the rate for each time point. Although each rate of increase was different at 15-30, the kinetics of the rate were relatively similar in these cases. As shown in Figure 2, the rate of [[beta].sub.1] decreased for the power regression line. Table 3 shows constants and the [r.sup.2] of the power regression lines. These comparisons showed the similarity of each CL response more clearly. However, the thickest fiber (RF3) and the thinnest fiber (TO1) had slightly lower correlations than other samples. The rate of RF3 was low in the acute phase, and the rate of TO1 was high in the acute phase.
[FIGURE 2 OMITTED]
The relationship between [[beta].sub.1] and fiber length. Figure 3 shows a representative time-dependent relation between geometric-mean length and [[beta].sub.1], used to examine the effect of fiber length on CL response. The results are shown in Table 4 with constants and the [r.sup.2] of the regression lines. A close correlation existed between length and [[beta].sub.1] at each time point, although four samples under approximately 6 [micro]m in length (SC1, PT1, MG1, and TO1) had a low [[beta].sub.1]. Therefore, a further close correlation existed between length and [[beta].sub.1] with samples > 6 [micro]m in length (GW1, RW1, RF1, RF2, RF3, SC1, and PT1) after 30 min. The relation between length and [[beta].sub.1] lasted from the acute phase of the reaction to 120 min.
[FIGURE 3 OMITTED]
The relationship between [[beta].sub.1] and fiber width. The World Health Organization (WHO) classifies mineral fibers based on length, width, and the aspect ratio of the fiber (25). Figure 4 shows the relation between geometric-mean width and [[beta].sub.1] at 15 and 45 min. The results are shown in Table 5 with constants and the [r.sup.2] of the regression. lines. As shown in Figure 4 and Table 5, we observed a close correlation between width and [[beta].sub.1] for eight samples < 1.8 [micro]m in width at 15 min ([r.sup.2] = 0.8766); however, this relationship did not continue ([r.sup.2] at 45 min = 0.5138). [[beta].sub.1] correlated with width more than with length at 15 min, but it correlated with length more than with width after 30 min.
[FIGURE 4 OMITTED]
The relationship between increase rate of [[beta].sub.1] and width. We examined the relationship between rate of [[beta].sub.1] and fiber width to demonstrate the effect of the width from 15 to 60 min. Figure 5 shows a representative relationship between rate of [[beta].sub.1] and fiber width. The results are shown in Table 6 with constants and the [r.sup.2] of the regression lines. Although the tendency of this relationship at 15-30 min resembles that of [[beta].sub.1] and width at 15 min (Figure 4A), we observed a correlation at 30-45 min [[r.sup.2] = 0.5309 (Figure 5B)] and at 45-60 min [[r.sup.2] = 0.7473 (Figure 5C)]. However, a slope of the regression line decreased over the time course. Moreover, as shown in Table 2, the increase of [[beta].sub.1] was similar in each sample after 60 min. Therefore, we saw no correlation at 60-75 min (Table 6).
[FIGURE 5 OMITTED]
The relationship between increase rate of [[beta].sub.1] and length. We also examined the relation between rate of [[beta].sub.1] and fiber length. The correlation between these could not be recognized at any time point (data not shown).
The relationship between CL response and fiber sample weight. The relationship between sample weight and GL response at 45 min is shown in Figure 6A. These data were the most rectilinear rec·ti·lin·e·ar
Moving in, consisting of, bounded by, or characterized by a straight line or lines: following a rectilinear path; rectilinear patterns in wallpaper. for the dose-response curve dose-response curve A graphic representation of the effects that varous doses of an agent–eg, ionizing radiation or a chemotherapeutic agent, have on a given parameter–eg, cell viability, mutation frequency, DNA damage, tumor growth or metastasis or in the time-course measurement. Table 7 shows a slope of regression line of the dose-response curves in mass concentration. MG1 had the highest level, and GW1 and RF3 had the lowest level. However, the linearity of dose-response curves did not continue in some samples. The relationship between sample weight and CL response at 120 min is shown in Figure 6B as reference. The dose-response curve of some samples was saturated at various levels. Short fibers tend to saturate sat·u·rate
v. Abbr. sat.
1. To imbue or impregnate thoroughly.
2. To soak, fill, or load to capacity.
3. To cause a substance to unite with the greatest possible amount of another substance. the dose-response curve at low dosage.
[FIGURE 6 OMITTED]
The results of the present study demonstrate the time course and rate of the induction of lucigenin-dependent CL in human monocyte-derived macrophages for various manmade and natural mineral fibers. Moreover, we examined the time-dependent relationships between fiber size and these parameters. Even when the dosed number of fibers differed for each sample, the ability to induce CL per fiber could be approximated using our analysis.
Many intrapleural studies led to the conclusion that the fibrous shape of asbestos dust particles is the cause of their carcinogenicity carcinogenicity /car·ci·no·ge·nic·i·ty/ (kahr?si-no-je-nis´i-te) the ability or tendency to produce cancer.
the ability or tendency to produce cancer. in humans and that basically all types of elongated dust particles such as mineral and vitreous vitreous /vit·re·ous/ (vit´re-us)
1. glasslike or hyaline.
2. vitreous body.
primary persistent hyperplastic vitreous fibers can induce tumors if they are sufficiently long, thin, and durable in the tissue (10,26). If this conclusion is true, common reactivity in the mechanism of tumor induction should exist between asbestos and mineral and vitreous fibers. Numerous studies have suggested that ROS may underlie the pathogenesis of asbestos-related lung diseases (11,27). However, amphibole asbestos, which includes iron in its fibers, plays a special role in ROS-mediated pathology because it catalyzes the generation of the reactive hydroxyl radical from hydrogen peroxide (11,28,29). In asbestos, the hydroxyl radical can alter various biologic effects (11-13). In biologic systems, superoxide usually acts as the reductant reductant /re·duc·tant/ (re-duk´tant) the electron donor in an oxidation-reduction (redox) reaction.
A reducing agent. producing [Fe.sup.2+], which rapidly decomposes hydrogen peroxide to hydroxyl radicals (29,30). The action of superoxide makes a chain of reactions in which the net process converts hydrogen peroxide to the hydroxyl radical (29,31). Paradoxically, superoxide activity may decide hydroxyl radical activity: in vivo in vivo /in vi·vo/ (ve´vo) [L.] within the living body.
Within a living organism.
in vivo adv. , because hydrogen peroxide has always been made in vivo if [Fe.sup.3+] exists in close proximity. Various mineral fibers cause a significant increase in the release of superoxide from macrophages (18,19). Moreover, tumorigenic fibers do not always have hydroxyl radical activity in vitro in vitro /in vi·tro/ (in ve´tro) [L.] within a glass; observable in a test tube; in an artificial environment.
In an artificial environment outside a living organism. (14). Silicon carbide fibers, one type of tumorigenic fiber, have no hydroxyl radical activity (14). Our findings here suggest that macrophages have common superoxide reactivity for various types of fiber and that the activity of superoxide from macrophages has an important role in biologic effects, depending on fiber length.
In early animal intraperitoneal studies, it was suggested that the induction of pleural Pleural
Pleural refers to the pleura or membrane that enfolds the lungs.
Mentioned in: Pneumothorax
emanating from or pertaining to the pleura. sarcoma sarcoma (särkō`mə), highly malignant tumor arising in connective- and muscle-cell tissue. It is the result of oncogenes (the cancer causing genes of some viruses) and proto-oncogenes (cancer causing genes in human cells). increased with the length of fibers with diameters < 1.5 [micro]m (32). However, a relation between ROS and fiber width has not been shown. We also tried to analyze the effect of fiber width on the ability to induce CL. Our results showed that wide fiber (a width of 2.4 [micro]m) has a low ability to induce CL and that thin fibers cause a large acceleration in the induction of CL in the acute phase. However, our findings suggest that the superoxide-mediated biologic effect of width is weak because the effect of width on the ability to induce CL was smaller than that of length. If a biologic effect of width does exist, thin fibers may be stronger than thick fibers of the same length.
WHO has classified fibers > 5 [micro]m long, < 3 [micro]m diameter, with an aspect ratio > 3:1 (25). Our findings suggest that many airborne WHO fibers induce superoxide release from macrophages depending on fiber length.
Long asbestos fibers are more effective than short fibers in eliciting the release of superoxide from macrophages (16). However, the molecular mechanism by which asbestos may augment the release of oxygen metabolites Metabolites
Substances produced by metabolism or by a metabolic process.
Mentioned in: Interactions from phagocytic cells Phagocytic cells
A cell that ingests microorganisms and foreign particles.
Mentioned in: Chronic Granulomatous Disease is unclear. One hypothesis is that oxidant oxidant /ox·i·dant/ (ok´si-dant) the electron acceptor in an oxidation-reduction (redox) reaction.
See oxidizer. release occurs nonspecifically during "frustrated" phagocytosis phagocytosis: see endocytosis.
A mechanism by which single cells of the animal kingdom, such as smaller protozoa, engulf and carry particles into the cytoplasm. by alveolar macrophages and polymorphonuclear leukocytes that are unable to ingest in·gest
tr.v. in·gest·ed, in·gest·ing, in·gests
1. To take into the body by the mouth for digestion or absorption. See Synonyms at eat.
2. long asbestos fibers completely (33). However, our findings do not support this hypothesis, because the time-dependent pattern (sigmoid type) and increase of ability to induce CL were similar for each sample except wollastonite (Figures 1,2). These findings suggest that though the release of superoxide from macrophages occurs nonspecifically for many mineral fibers, the intensity had already been decided when fibers were phagocytosed to some extent. If the release of superoxide occurs during "frustrated" phagocytosis, the intensity of that of short fibers should decrease with the advance of phagocytosis.
We speculated as to the reason why the ability to induce CL increased with fiber length when samples were longer than approximately 6 [micro]m. The regular transition in the rate to induce CL in each sample suggests that the intensity of the CL response is decided at the initial stage of phagocytosis. However, it cannot be considered that macrophages recognized fiber length at the initial stage of phagocytosis. In observations by optical microscope, short fibers were perpendicularly phagocytosed, and long fibers were often tangentially tan·gen·tial also tan·gen·tal
1. Of, relating to, or moving along or in the direction of a tangent.
2. Merely touching or slightly connected.
3. phagocytosed (data not shown). Therefore, we speculated that tangential tan·gen·tial also tan·gen·tal
1. Of, relating to, or moving along or in the direction of a tangent.
2. Merely touching or slightly connected.
3. phagocytosis has a stronger effect on the ability to induce CL than perpendicular phagocytosis. If this speculation is true, a cause of the enhanced ability to induce CL may be the increase in the tangential phagocytic phag·o·cyt·ic
1. Of or relating to phagocytes.
2. Of, relating to, or characterized by phagocytosis.
emanating from or pertaining to phagocytes. rate with lengthening of fiber. Moreover, we speculated that tangential phagocytosis shifts to perpendicular phagocytosis with fibers under approximately 6 [micro]m in length.
In general, many experimental protocols have been conducted based on the mass concentration of fiber samples. Therefore, we also show the CL response per sample weight (Figure 6A) to allow comparison with other experimental results. In comparison by mass concentration, our data showed that the CL response is weak in both the short samples and samples such as glass wool and rock wool, which have low fiber numbers per unit weight. Mass concentration study of glass wool and rock wool showed no significant increase in tumor incidence in rats (4,5). The data in Figure 6A are consistent with these in vivo results. Moreover, a durable special application fiber glass (MMVF (MultiMedia Video File) See MVDisc. 33, 106 fibers/cc > 20 [micro]m) induced lung fibrosis and a single mesothelioma Mesothelioma Definition
Mesothelioma is an uncommon disease that causes malignant cancer cells to form within the lining of the chest, abdomen, or around the heart. Its primary cause is believed to be exposure to asbestos. in hamsters; however, insulation fiber glass (MMVF10a, 151 fibers/cc > 20 [micro]m) did not induce lung fibrosis or tumors (34). The data in Figure 1 are consistent with the finding that the glass fiber is not inert.
Previous studies with various mineral particles have suggested that the fibrous geometry of particulates is of critical importance in the generation of superoxide from macrophages (16,18,35). For example, for amosite asbestos, dramatic enhancement of release of superoxide has been found with long fibers but not short ones (35). The distribution of length of the long fibers (50% > approximately 14 [micro]m long) is similar to that of RF1 (mean length 12.0 [micro]m), and the distribution of length of the short fibers (10% > approximately 10 [micro]m long) is similar to that of MG1 (mean length 3.0 [micro]m). Therefore, our data on the relationship between fiber length and ability to induce CL are consistent with the asbestos data. Moreover, our findings suggest that this relationship continues over the time course without effect of fiber clearance. In contrast, murine murine /mu·rine/ (mur´en) pertaining to, derived from, or characteristic of mice or rats.
adj. peritoneal peritoneal /peri·to·ne·al/ (per?i-to-ne´al) pertaining to the peritoneum.
pertaining to the peritoneum. macrophages exposed to equal numbers of short and long crocidolite crocidolite
or blue asbestos
Gray-blue to green, highly fibrous (asbestiform) form of the amphibole mineral riebeckite. It has higher tensile strength than chrysotile asbestos. asbestos fibers exhibited comparable hydrogen peroxide release (36). However, the mean length of the long crocidolite fiber was 5.4 [micro]m, and the mean length of short fiber was 1.2 [micro]m. Our finding that the ability to induce CL was similar among fibers under approximately 6 [micro]m in length was also consistent with the hydrogen peroxide data.
These assays were performed with suspended cells over a time course of 2 hr. Many previous published studies of effects of asbestos and mineral fibers on oxidant production from alveolar macrophages have used cells in suspension. However, many studies of the effect of fiber length on oxidant production and using monocyte-derived macrophages have used adherent cells. For some applications, suspended cells work better than adherent cells for comparing the response of cells. First, the number of cells in each vial will be identical with that of cell suspension. Second, the cells will have diffuse contact with the fibers. We believe that this advantage contributes to linearity of the dose-response curve of CL response. Finally, the cells may smoothly phagocytose phag·o·cy·tose
to envelop and destroy bacteria and other foreign material; phagocytize. the fiber. We consider that these advantages help reduce experimental error.
One problem is whether wollastonite is an exception. Although WO 1 was excluded in our analyses, [r.sup.2] and [[beta].sub.1] of WO1 increased over the time course (Table 1). The response for WO1 may be retarded; however, our data are not sufficient to define WO1 as an exception.
In conclusion, it is suggested that macrophages nonspecifically induce superoxide for various fiber types depending on fiber length. Although the generation of hydroxyl radical may be the most important difference between amphibole asbestos and other mineral fibers, superoxide is a tumor promoter tumor promoter Cocarcinogen A substance, often lipid-soluble, that has no intrinsic carcinogenic potential, but which, when applied repeatedly, amplifies cancer-inducing effects of other (initiator) substances. See Antipromoter. Cf Tumor initiator. and is involved in the generation of hydroxyl radical. Our findings suggested that even inert mineral fibers were not safe if the conditions of durability, clearance, and respirability res·pi·ra·ble
1. Fit for breathing: respirable air.
2. Capable of undergoing respiration: respirable organisms. are satisfied. Our findings have also revealed important differences from the hypothesis that oxidant release occurs during "frustrated" phagocytosis. A remaining problem is to elucidate the reasons why macrophages have high superoxide activity for long fibers.
Table 1. Constants and [r.sup.2] of the regression lines for CL and estimated number of fibers. 0 15 Time (a) (min) [[beta].sub.1] (b) [r.sup.2] (c) [[beta].sub.1] [r.sup.2] GW1 15.34 0.110 280.0 0.960 RW1 9.869 0.406 345.4 0.966 MG1 0.436 0.339 21.97 0.972 RF1 0.664 0.020 168.3 0.920 RF2 -0.75 0.028 214.3 0.985 RF3 7.742 0.422 177.0 0.978 PT1 -0.03 0.162 2.130 0.971 SC1 0.307 0.228 7.600 0.917 TO1 -0.03 0.203 1.520 0.977 WO1 -0.29 0.072 -5.69 0.450 30 45 Time (a) (min) [[beta].sub.1] [r.sup.2] [[beta].sub.1] [r.sup.2] GW1 1,052 0.958 2,492 0.942 RW1 1,072 0.979 1,920 0.961 MG1 66.20 0.902 112.1 0.818 RF1 517.9 0.992 1,021 0.985 RF2 562.2 0.988 893.9 0.967 RF3 371.0 0.992 539.1 0.979 PT1 6.100 0.940 9.600 0.896 SC1 24.40 0.992 49.20 1.000 TO1 3.200 0.974 7.000 0.988 WO1 -2.90 0.041 8.900 0.124 60 75 Time (a) (min) [[beta].sub.1] [r.sup.2] [[beta].sub.1] [r.sup.2] GW1 3,489 0.927 4,333 0.941 RW1 2,735 0.959 3,581 0.952 MG1 153.8 0.815 182.0 0.819 RF1 1,601 0.975 1,955 0.952 RF2 1,219 0.944 1,447 0.921 RF3 669.1 0.937 910.5 0.982 PT1 11.40 0.818 10.40 0.685 SC1 77.80 0.996 110.6 0.996 TO1 11.00 0.913 12.00 0.822 WO1 28.20 0.338 61.80 0.580 90 105 Time (a) (min) [[beta].sub.1] [r.sup.2] [[beta].sub.1] [r.sup.2] GW1 4,643 0.920 4,642 0.947 RW1 3,946 0.924 4,209 0.937 MG1 179.8 0.798 162.7 0.761 RF1 2,035 0.928 1,877 0.865 RF2 1,538 0.916 1,439 0.897 RF3 914.7 0.970 997.0 0.970 PT1 8.900 0.608 6.700 0.484 SC1 123.1 0.994 128.9 0.992 TO1 11.10 0.738 9.400 0.662 WO1 95.30 0.688 118.8 0.765 120 Time (a) (min) [[beta].sub.1] [r.sup.2] GW1 4,735 0.940 RW1 4,352 0.938 MG1 142.2 0.735 RF1 1,580 0.780 RF2 1,327 0.848 RF3 1,021 0.967 PT1 4.800 0.373 SC1 132.4 0.990 TO1 7.300 0.607 WO1 137.1 0.786 (a) Time after administration; CL responses of 54 samples were measured in constant rotation at 15-min intervals with the same stock suspension of cells. (b) [[beta].sub.1] (x [10.sup.-9]) is the slope of the regression line for the estimated number of fibers administered and CL response with 5 concentrations and a duplicate negative control. The CL response is the mean value of the four measurements. (c) Square of the correlation coefficient of the regression line. Table 2. Time course of the rate of increase in [[beta].sub.1], in 15-min intervals. 1 2 3 4 No. (a) (15-30) (30-45) (45-60) (60-75) GW1 3.757 2.369 1.400 1.242 RW1 3.104 1.791 1.424 1.309 MG1 3.012 -- (b) -- -- RF1 3.078 1.971 1.569 1.221 RF2 2.623 1.590 1.364 1.186 RF3 2.096 1.453 1.241 1.361 PT1 2.845 -- -- -- SC1 3.216 2.013 1.582 1.421 TO1 2.131 2.165 1.572 -- Average 2.874 1.907 1.450 1.290 SD 0.498 0.296 0.120 0.082 5 6 7 No. (a) (75-90) (90-105) (105-120) GW1 1.072 1.000 1.020 RW1 1.102 1.067 1.034 MG1 -- -- -- RF1 1.041 -- -- RF2 1.063 -- -- RF3 1.005 1.090 1.024 PT1 -- -- -- SC1 1.113 1.047 1.027 TO1 -- -- -- Average 1.066 1.051 1.026 SD 0.036 0.033 0.005 (a) Time-course order of the rate of increase in [[beta].sub.1]. The rates were calculated between continuing two data points, in minutes. For example, the values at 1 are [[beta].sub.1] at 30 min divided by the [[beta].sub.1] at 15 min. (b) The defects were the cases where [r.sup.2] < 0.9. Table 3. Constants and the [r.sup.2] of the power regression lines for time course of the rate of increase in [[beta].sub.1] Fibers A (a) B (a) [r.sup.2] (b) n (c) GW1 3.601 -0.720 0.961 7 RW1 2.849 -0.563 0.970 7 MG1 -- -- -- 1 RF1 3.123 -0.669 0.9959 5 RF2 2.512 -0.550 0.9829 5 RF3 1.983 -0.356 0.8972 7 PT1 -- -- -- 1 SC1 3.136 -0.693 0.9889 7 TO1 2.240 -0.245 0.5681 3 (a) Constants of the power regression line for the time course of the rate in Figure 2. For convenience, numbering was used to estimate the regression line. Equation, Y = A[X.sup.B]; Y = rate of increase in Table 2, X = numbering of the rate in Table 2. (b) Square of the correlation coefficient of the power regression line. Though constant, A changes with the numbering; constant B and [r.sup.2] are fixed. (c) Effective number. Table 4. Constants and the [r.sup.2] of the regression lines for [[beta].sub.1] of Table 1 and fiber length. Time (a) 0 15 30 45 60 A (b) 0.080 2.027 68.27 149.7 211.2 B (b) -4.062 -6.286 -259.1 -700.4 -983.5 [r.sup.2] (c) 0.677 0.852 0.906 0.916 0.907 n (d) 9 9 9 7 7 A (e) 1.068 23.04 82.77 186.8 263.2 B (e) -7.910 -102.2 -465.1 -1,241 -1,741 [r.sup.2] (f) 0.738 0.819 0.937 0.976 0.962 n 7 7 7 6 6 Time (a) 75 90 105 120 A (b) 332.1 360.7 367.3 376.2 B (b) -2,200 -2,423 -2,456 -2,509 [r.sup.2] (c) 0.965 0.957 0.946 0.943 n (d) 6 6 4 4 A (e) 332.1 360.7 367.3 376.2 B (e) -2,200 -2,423 -2,456 -2,509 [r.sup.2] (f) 0.965 0.957 0.946 0.943 n 6 6 4 4 (a) Time after administration (min). (b) Analysis for nine samples. A and B are constants of the regression line for [[beta].sub.1] and fiber length. Equation: Y = AX + B; Y = [[beta].sub.1] of Table 1, X = geometric-mean length of fibers, A, B = constants (x [10.sup.-9]). (c) Square of the correlation coefficient of the regression line with whole samples. (d) Effective number. The data < 0.9 in [r.sup.2] of Table 1 were excluded, except for time 0. The data of time 0 are reference data. All effective data after 75 min were samples > 6 [micro]m in length. (e) Analysis for seven samples > 6 [micro]m in length. A,B and equation were the same as b. (f) Square of the correlation coefficient of the regression line with samples > 6 [micro]m in length. Table 5. Constants and the [r.sup.2] of the regression lines for [[beta].sub.1] of Table 1 and fiber width, except RF3. Time (a) 0 15 30 45 60 A (b) 5.930 232.8 719.7 1,196 1,686 B (b) -0.911 -32.26 -88.98 68.85 119.7 [r.sup.2] (c) 0.311 0.877 0.775 0.514 0.515 n (d) 8 8 8 6 6 Time (a) 75 90 105 120 A (b) 1,917 2,134 2,429 2,519 B (b) 426.2 386.6 580.1 571.3 [r.sup.2] (c) 0.387 0.407 0.545 0.556 n (d) 5 5 3 3 (a) Time after administration (min). (b) Analysis for eight samples < 1.8 [micro]m in width. A and B are constants of the regression line for [[beta].sub.1] and fiber width. Equation: Y = AX + B; Y = [[beta].sub.1] of Table 1, X = geometric-mean width of fibers, A,B = constants (x [10.sup.-9]). (c) Square of the correlation coefficient of the regression line. (d) Effective number. The data < 0.9 in [r.sup.2] of Table 1 were excluded, except for time 0. The data of time 0 are reference data. Table 6. Constants and the [r.sup.2] of the regression lines for the rate of increase in Table 2 and fiber width. No. (a) 1 2 3 4 5 6 7 A (b) -0.161 -0.290 -0.139 0.012 -0.029 0.029 0.001 B (b) 3.016 2.213 1.597 1.276 1.101 1.012 1.025 [r.sup.2] (c) 0.055 0.531 0.747 0.010 0.316 0.505 0.044 n (d) 9 7 7 6 6 4 4 (a) Time-course order of the rate of increase in Table 2. (b) Constants of the regression line for the rate in Table 2 and fiber width. Equation: Y = AX+B; Y = the rate in Table 2, X = geometric-mean width of fibers. (c) Square of the correlation coefficient of the regression line. (d) Effective number. The data < 0.9 in [r.sup.2] of Table 1 were excluded. Table 7. A slope of regression line of each dose-response curve at 45 min in mass concentration. Sample GW1 RW1 MG1 RF1 RF2 Slope (CL/mg) 1.744 3.264 7.285 8.980 7.777 Sample RF3 PT1 SC1 TO1 Slope (CL/mg) 1.887 5.658 20.18 4.495 Each [r.sup.2] was the same as that of Table 1.
REFERENCES AND NOTES
(1.) Craighead JE, Mossman BT. The pathogenesis of asbestos-associated diseases. N Engl J Med 306:1446-1455 (1982).
(2.) Mossman BT, Bignon J, Corn M, Seaton A, Gee JB. Asbestos: scientific developments and implications for public policy. Science 24:294-301 (1990).
(3.) Ellouk SA, Jaurand MC. Review of animal/in vitro data on biological effects of man-made fibers. Environ Health Perspect 102(suppl 2):47-61 (1994).
(4.) McConnell EE, Wagner JC, Skidmore JW, Moore JA. A comparative study of the fibrogenic and carcinogenic effects of UICC UICC Union International Contre le Cancer International Union against Cancer Canadian chrysotile B asbestos and glass microfibre (JM 100). In: Biological Effects of Man-Made Mineral Fibres. Proceedings of a WHO/IARC Coference, Vol 2. Copenhagen:World Health Organization, 1984;234-252.
(5.) Wagner JC, Berry DB, Hill RJ, Munday DE, Skidmore JW. Animal experiments with MMM MMM Myeloid metaplasia with myelofibrosis, see there (V)F: effects of inhalation and intrapleural inoculation inoculation, in medicine, introduction of a preparation into the tissues or fluids of the body for the purpose of preventing or curing certain diseases. The preparation is usually a weakened culture of the agent causing the disease, as in vaccination against in rats. In: Biological Effects of Man-Made Mineral Fibres. Proceedings of a WH0/IARC Coference, Vol 2. Copenhagen:World Health Organization, 1984;209-233.
(6.) Bunn WB, Bender JR, Hesterberg TW, Chase GR, Konzen JL. Recent studies of man-made vitreous fibers. J 0ccup Med 35:101-113 (1993).
(7.) Hesterberg TW, Chase G, Axten C, Miller WC, Musselman RP, Kamstrup O, Hadley J, Morscheidt C, Bernstein DM, Thevenaz P. Biopersistence of synthetic vitreous fibers and amosite asbestos in the rat lung following inhalation. Toxicol Appl Pharmacol 151:262-275 (1998).
(8.) Stanton MF, Layard M, Tegeris A, Miller E, May M, Morgan E, Smith A. Relation of particle dimension to carcinogenicity in amphibole asbestoses and other fibrous minerals. J Natl Cancer Inst 67:965-975 (1981).
(9.) Davis JM, Addison J, Bolton RE, Donaldson K, Jones AD, Smith T. The pathogenicity of long versus short fibre samples of amosite asbestos administered to rats by inhalation and intraperitoneal injection. Br J Exp Pathol 67:415-430 (1986).
(10.) Roller M, Pott F, Kamino K, Althoff GH, Bellmann B. Results of current intraperitoneal carcinogenicity studies with mineral and vitreous fibres. Exp Toxicol Pathol 48:3-12 (1996).
(11.) Kamp DW, Graceffa P, Pryor WA, Weitzman SA. The role of free radicals in asbestos-induced diseases. Free Radic Biol Med 12:293-315 (1992).
(12.) Hardy JA, Aust AE. Iron in asbestos chemistry and carcinogenicity. Chem Rev 95:415-430 (1986).
(13.) Shull S, Manohar M, Marsh KP, Janssen YM, Mossman BT. Role of iron and reactive oxygen species in asbestos-induced lung injury. In: Free Radical Mechanisms of Tissue Injury (Moslen T, Smith CV, eds). Boca Raton, FL:CRC (Cyclical Redundancy Checking) An error checking technique used to ensure the accuracy of transmitting digital data. The transmitted messages are divided into predetermined lengths which, used as dividends, are divided by a fixed divisor. Press, 1992;153-162.
(14.) Brown DM, Fisher C, Donaldson K. Free radical activity of synthetic vitreous fibers: iron chelation Chelation
The process by which a molecule encircles and binds to a metal and removes it from tissue.
Mentioned in: Heavy Metal Poisoning
chelation inhibits hydroxyl radical generation by refractory ceramic fiber. J Toxicol Environ Health 53:545-561 (1998).
(15.) Pott F, Schlipkoter HW, Ziem U, Spumy spume
Foam or froth on a liquid, as on the sea.
intr.v. spumed, spum·ing, spumes
To froth or foam.
[Middle English, from Old French espume, from Latin K, Huth F. New results from implantation experiments with mineral fibers. In: Biological Effects of Man-Made Mineral Fibres. Proceedings of a WHO/IARC Conference, Vol 2. Copenhagen: World Health Organization, 1984;285-302.
(16.) Mossman BT, Marsh JP, Shatos MA, Doherty J, Gilbert R, Hill S. Implication of oxygen species as second messengers Second messengers
Molecules used to transmit signals within cells. These molecules trigger a cascade of events by activating other cellular components. of asbestos toxicity. Drug Chem Toxicol 10:157-180 (1987).
(17.) Mossman BT, Sesko AM. In vitro assays to predict the pathogenicity of mineral fibers. Toxicology 60:53-61 (1990).
(18.) Hansen K, Mossman BT. Generation of superoxide from alveolar macrophages exposed to asbestiform and nonfibrous particles. Cancer Res 47:1681-1686 (1987).
(19.) Ruotsalainen M, Hirvonen MR, Luoto K, Savolainen KM. Production of reactive oxygen species by man-made vitreous fibres in human polymorphonuclear leukocytes. Hum Exp Toxicol 18:354-362 (1999).
(20.) Ohyama M, Otake T, Morinaga K. The chemiluminescent chem·i·lu·mi·nes·cence
Emission of light as a result of a chemical reaction at environmental temperatures.
chem response from human monocyte-derived macrophages exposed to various mineral fibers of different sizes. Ind Health 38:289-293 (2000).
(21.) Kohyama N, Tanaka I, Tomita M, Kudo ku·do
n. pl. ku·dos
Usage Problem A praising remark; an accolade or compliment: "Children's book author Virginia Hamilton added another kudo to her prize-laden career" M, Shinohara Y. Preparation and characteristics of standard reference samples of fibrous minerals for biological experiments. Ind Health 35:415-432 (1997).
(22.) Yamato H, Morimoto Y, Tsuda T, 0hgami A, Kohyama N, Tanaka I. Fiber numbers per unit weight of JFM standard reference samples determined with a scanning electron microscope scan·ning electron microscope
n. Abbr. SEM
An electron microscope that forms a three-dimensional image on a cathode-ray tube by moving a beam of focused electrons across an object and reading both the electrons scattered by the object and . Ind Health 36:384-387 (1998).
(23.) Boyum A. Isolation of mononuclear mononuclear /mono·nu·cle·ar/ (-noo´kle-er)
1. having but one nucleus.
2. a cell having a single nucleus, especially a monocyte of the blood or tissues.
adj. cells and granulocytes Granulocytes
White blood cells.
Mentioned in: Blood Donation and Registry
granulocytes (granˑ·y from human blood. Scand J Clin Lab Invest 21:77-89 (1968).
(24.) Nyberg P, Klockars M. Measurement of reactive oxygen metabolites produced by human monocyte-derived macrophages exposed to mineral dusts. Int J Exp Path 71:537-544 (1990).
(25.) WHO. Reference Methods for Measuring Man-Made Mineral fibers (MMMF MMMF Money Market Mutual Fund
MMMF Man Made Mineral Fibre
MMMF Maximum Margin Matrix Factorization ). Copenhagen:World Health Organization, 1985.
(26.) Asbestiform Fibers. Nonoccupational Health Risks. Washington, DC:National Academy Press, 1984.
(27.) Vallyathan V, Mega JF, Shi X, Dalai NS. Enhanced generation of free radicals from phagocytes induced by mineral dusts. Am J Respir Cell Mol Biol 6:404-413 (1992).
(28.) Weitzman SA, Graceffa P. Asbestos catalyzes hydroxyl hydroxyl /hy·drox·yl/ (hi-drok´sil) the univalent radical OH.
The univalent radical or group OH, a characteristic component of bases, certain acids, phenols, alcohols, carboxylic and superoxide radical generation from hydrogen peroxide. Arch Biochem Biophys 228:373-376 (1984)
(29.) Fenton HJH HJH Henry John Heinz
(30.) Halliwell B, Gutteridge JMC JMC Joint Military Commission
JMC Jefferson Medical College
JMC Jax Money Crew (computer gaming)
JMC Joint Munitions Command (US Army; Rock Island Arsenal, Rock Island IL)
JMC James Madison College . Oxygen free radicals and iron in relation to biology and medicine: some problems and concepts. Arch Biochem Biophys 246:501-514 (1986)
(31.) Halliwell B, Gutteridge JMC. Oxygen toxicity Oxygen toxicity
A toxic effect in a living organism caused by a species of oxygen. Oxygen has two aspects, one benign and the other malignant. Those organisms that avail themselves of the enormous metabolic advantages provided by dioxygen (O2 , oxygen radicals, transiton metals and disease. Biochem J 219:1-14 (1984)
(32.) Stanton MF, Laynard M, Tegeris A, Miller E, May M, Kent E. Carcinogenicity of fibrous glass: pleural response in the rat in relation to fiber dimension. J Natl Cancer Inst 58:587-603 (1977).
(33.) Archer VE. Carcinogenicity of fibers and films: a theory. Med Hypotheses 5:1257-1260 (1979).
(34.) Hesterberg TW, Axten C, McConnell EE, Oberdorster G, Everitt J, Miiller WC, Chevalier J, Chase GR, Thevenaz P. Chronic inhalation study of fiber glass and amosite asbestos in hamsters: twelve-month preliminary results. Environ Health Perspect 105(suppl 5):1223-1229 (1997).
(35.) Hill IM, Beswick PH, Donaldson K. Differential release of superoxide anions by macrophages treated with long and short fibre amosite asbestos is a consequence of differential affinity for opsonin opsonin /op·so·nin/ (op´son-in) an antibody that renders bacteria and other cells susceptible to phagocytosis.opson´ic
immune opsonin . Occup Environ Med 52:92-98 (1995).
(36.) Goodglick LA, Kane AB. Cytotoxicity of long and short crocidolite asbestos fibers in vitro and in vivo. Cancer Res 50:5153-5163 (1990).
Masayuki Ohyama, (1) Toru Otake, (1) and Kenji Morinaga (2)
(1) Osaka Prefectural pre·fec·ture
1. The district administered or governed by a prefect.
2. The office or authority of a prefect.
3. The residence or housing of a prefect. Institute of Public Health, Nakamichi, Higashinari-ku, Osaka, Japan; (2) Osaka Medical Center for Cancer and Cardiovascular Diseases, Nakamichi, Higashinari-ku, Osaka, Japan
Address correspondence to M. Ohyama, Osaka Prefectural Institute of Public Health, 1-3-69, Nakamichi, Higashinari-ku, Osaka 537-0025, Japan. Telephone: +81-6-6972-1321 Fax: +81-6-6972-2393. E-mail: email@example.com
We thank the Japan Fibrous Material Research Association for supplying the Japan Fibrous Material standard reference samples.
Received 25 December 2000; accepted 4 April 2001.