Pituitary adenomas producing almost exclusively growth hormones (GH) have been ultrastructurally classified into two distinct types: densely granulated somatotroph (DG) adenomas and sparsely granulated (SG) adenomas. Fibrous body (FB), an intracytoplasmic globular aggregation of cytokeratin (CK) filaments, is a hallmark of SG adenomas. Under light microscope, FB could be identified by CK immunohistochemistry as a dot-pattern immunoreaction versus a perinuclear pattern for cells without FB. However, it has been noted that numerous adenomas contain mixed populations of the two patterns. To clarify clinicopathological characteristics of the adenomas with mixed populations ("intermediate type" adenomas) and to confirm clinicopathological differences between strictly defined DG-type and SG-type adenomas, we performed this study on 104 GH cell adenomas. Having segregated "intermediate-type" adenomas (26 cases), we found significant differences between typical DG-type (47 cases) and SG-type adenomas (31 cases); SG-type adenomas had younger ages (44 vs. 50), higher frequency of macroadenomas (86% vs. 58%), invasiveness (65% vs. 38%), advanced grades (3 or 4) in Knosp's classification (50% vs. 24%), and weaker immunoreaction for GH, beta-TSH, alpha-subunit, E-cadherin, and beta-catenin. Clinicopathological characteristics of "intermediate-type" adenomas were identical to those of DG-type adenomas. These findings confirm that SG-type adenoma is a distinct section of GH cell adenomas with special properties and biological behavior, and suggest that intermediate-phenotype adenomas are enrolled in DG-type adenomas. Special properties and biological behavior of SG-type adenomas may appear after the majority of tumor cells possess a fully developed fibrous body.

From a clinical standpoint, it is quite important to differentiate morphological type in CNFPAs to aid the clinician in assessing the clinical behavior and prognosis of the tumor. Therefore, we suggest that all CNFPAs be examined not only by conventional light microscopy but also by immunohistochemistry, preferably by electron microscopy, to achieve a correct morphological diagnosis.

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Polystyrene used for food containers, such as takeout food containers, coffee cups, meat trays, soup bowls, and salad boxes (1), contains high levels of styrene dimers (90-1,030 µg/g) and styrene trimers (650-20,770 µg/g) as impurities (2,3). These styrene oligomers migrate from the polystyrene containers into the containers' contents (4-6). When polystyrene containers containing vegetable oil were treated by heating in a microwave oven or were incubated for 24 hr at 20°C, a styrene dimer, 2,4-diphenyl-1-butene (SD-2; 0-1.6 ng/cm 2 ) and styrene trimers 2,4,6-triphenyl-1-hexene (ST-1; 1.3-69.7 ng/cm 2 ), 1a-phenyl-4a-(1´-phenylethyl)tetralin (ST-2; 9.2-156 ng/cm 2 ), 1a-phenyl-4e-(1´-phenylethyl)tetralin (ST-3; 18.1-501 ng/cm 2 ), 1e-phenyl-4a-(1´-phenylethyl)tetralin (ST-4; 13.9-294 ng/cm 2 ), and 1e-phenyl-4e-(1´-phenylethyl)tetralin (ST-5; 18.7-306 ng/cm 2 ) migrated into the vegetable oil (4). When instant foods such as Chinese noodles, Japanese noodles, buckwheat noodles, chow mein, spaghetti, and rice were packed in polystyrene containers, styrene trimers ST-1 (0-8.1 µg/cup), ST-2 + ST-3 (0-13.8 µg/cup), ST-4 (0-5.2 µg/cup), and ST-5 (0-8.4 µg/cup) migrated (0-33.8 µg total styrene oligomers detected in a cup) from the containers into the foods after cooking in the cups, but the dimers did not (5). The maximum quantity of styrene trimers that migrated from containers to foods was higher than that of bisphenol A leached from the lacquer coating of vegetable cans (4-23 µg/can) (7).Colborn et al. (8) designated styrene dimers and trimers as endocrine disrupters in the Wingspread statement, and the Environmental Agency, Government of Japan, cited styrene dimers and trimers as compounds suspected of having endocrinedisruptive effects in its Strategic Programs on Environmental Endocrine Disrupters (9). However, styrene oligomers were reported to have no endocrine disruptive effect both in a MCF-7 cell proliferation assay (10) and in a radioisotope (RI) receptor competitive-binding assay using rat estrogen receptor (10,11). Therefore, we tested 11 styrene oligomers including those found in food (4,5) in a proliferation assay at an optimal initial cell concentration using human breast tumor, highly estrogen-sensitive MCF-7 cells. We also examined the binding potency of these styrene oligomers to human estrogen receptor α (hERα) in a non-RI receptor competitivebinding assay. Materials and MethodsChemicals. The styrene dimers 1,3-diphenyl propane (SD-1), SD-2, cis-1,2-diphenyl cyclobutane (SD-3), and trans-1,2-diphenyl cyclobutane (SD-4) and styrene trimers ST-1, ST-2, ST-3, ST-4, ST-5, 1e,3e,5a-triphenylcyclohexane (ST-6), and 1e,3e,5e-triphenylcyclohexane (ST-7) were purchased from Hayashi Pure Chemical Industry. (Osaka, Japan). The positive control, 17β-estradiol (E 2 ), was obtained from Calbiochem (Richmond, CA, USA). The chemical structures of these compounds are shown in Figure 1, and the purity of the compounds is summarized in Table 1.Solvent for styrene oligomers. Styrene oligomers and E 2 were dissolved ...

-A possible teratogenicity of multi-wall carbon nanotube (MWCNT) was assessed using ICR mice. MWCNTs were suspended in 2% carboxymethyl cellulose and given intraperitoneally or intratracheally to pregnant ICR mice on day 9 of the gestation. All fetuses were removed from the uterus on day 18 of the gestation, and were examined for external and skeletal anomalies. In the intraperitoneal study, various types of malformation were observed in all MWCNT-treated groups (2, 3, 4 and 5 mg/kg body weight, intraperitoneal). In contrast, such malformations were observed in groups given 4 or 5 mg/kg body weight, but not in that treated with 3 mg/kg in the intratracheal study. In either study, the number of litters having fetuses with external malformation and that of litters having fetuses with skeletal malformations were both increased in proportion to the doses of MWCNT. The present results are the first to report that MWCNT possesses the teratogenicity at least under the present experimental conditions. Mechanism(s) to result such malformations is yet unclear and further experiment is necessary.