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A 90-kD lymphocyte surface glycoprotein, defined by monoclonal antibodies of the Hermes series, is involved in lymphocyte recognition of high endothelial venules (HEV). Lymphocyte gp90Hermes binds in a saturable, reversible fashion to the mucosal vascular addressin (MAd), a tissue-specific endothelial cell adhesion molecule for lymphocytes. We and others have recently shown that the Hermes antigen is identical to or includes CD44 (In[Lu]-related p80), human Pgp-1, and extracellular matrix receptor III-molecules reportedly expressed on diverse cell types. Here, we examine the relationship between lymphoid and nonlymphoid Hermes antigens using serologic, biochemical, and, most importantly, functional assays. Consistent with studies using mAbs to CD44 or Pgp-1, mAbs against five different epitopes on lymphocyte gp90Hermes reacted with a wide variety of nonhematolymphoid cells in diverse normal human tissues, including many types of epithelium, mesenchymal elements such as fibroblasts and smooth muscle, and a subset of glia in the central nervous system. To ask whether these non-lymphoid molecules might also be functionally homologous to lymphocyte homing receptors, we assessed their ability to interact with purified MAd using fluorescence energy transfer techniques. The Hermes antigen isolated from both glial cells and fibroblasts--which express a predominant 90-kD form similar in relative molecular mass, isoelectric point, and protease sensitivity to lymphocyte gp90Hermes--was able to bind purified MAd. In contrast, a 140-160-kD form of the Hermes antigen isolated from squamous epithelial cells lacked this capability. Like lymphocyte binding to mucosal HEV, the interaction between glial gp90Hermes and MAd is inhibited by mAb Hermes-3, but not Hermes-1, suggesting that similar molecular domains are involved in the two binding events. The observation that the Hermes/CD44 molecules derived from several nonlymphoid cell types display binding domains homologous to those of lymphocyte homing receptors suggests that these glycoproteins represent a novel type of cell adhesion/recognition molecule (H-CAM) potentially mediating cell-cell or cell-matrix interactions in multiple tissues.

We reviewed the pathophysiology of our previously reported female patient who had glucocorticoid-responsive hyperaldosteronism and was treated successfully with daily dose of dexamethasone (Dex) for 21 years. In this present study, the possibility that the patient may have 17 alpha-hydroxylase deficiency (17-OH-D) mainly in the adrenal could not be ruled out. We therefore reviewed 31 Japanese patients diagnosed as having 17-OH-D with suppressed plasma renin activity reported in Japan. Among these patients, 9 were found to have a high plasma aldosterone (Ald) concentration (PAC) (group I). Twenty-one patients had either normal or low-normal PAC and the remaining patient had low urine Ald (group II). The slight cross-reactivity of the anti-Ald-antibodies used with 17-deoxy-steroids such as progesterone, 11-deoxycorticosterone and corticosterone which were increased in both groups did not explain the increased PAC in group I. In the patients in group I and group II with high-normal basal PAC, PAC further increased after ACTH and was suppressed by Dex. PAC in 2 group I patients, however, did not respond to angiotensin-II or angiotensin-III infusion. PAC in patients in group II with low or low-normal basal PAC responded equivocally to ACTH and Dex. The basal plasma cortisol in group I was lower than in group II, and plasma cortisol level after ACTH in group I appeared to remain at a lower level than that in group II patients. Among the study subjects, 28 showed a negative correlation between basal PAC and plasma cortisol. A possible discrepancy in the deficiency of 17 alpha-hydroxylase activity in adrenal and gonadal glands was also suggested in three 17-OH-D patients. The pathophysiology of Ald secretion and discrepancy in the deficiency of the enzyme activities in both glands in 17-OH-D patients was discussed.

A 13-year-old girl with preB-ALL was admitted because of headache during maintenance therapy including L-asparaginase. Magnetic resonance imaging revealed cerebral thrombosis. Coagulation studies showed decreased levels of fibrinogen, antithrombin-III and plasminogen. The patient was treated with antithrombin-III concentrates and fresh frozen plasma and recovered quickly. These findings suggest that coagulopathy induced by L-asparaginase is associated with the pathogenesis of cerebral thrombosis.

In 75 patients with acute cerebral vascular disease (infarction 43, TIA 4, cerebral hemorrhage 25, subarachnoid hemorrhage 3), the plasma levels of Antithrombin-III (AT-III) and plasminogen (Plg) were measured within one week stroke patient and with 27 non-stroke patient as controls. The results showed: the plasma AT-III level was of no significant difference between the patients with hemorrhagic or ischemic cerebral vascular disease group and control group; the plasma plg level was a significant decrease in ischemic cerebral vascular disease groups (cerebral infarction. TIA), and it was of significant difference between the cerebral infarction group, or the TIA group and those of the control group (P less than 0.001 and P less than 0.01) respectively. In view of these results suggest that measuring of Plasma Plg level is a valuable unspecific assays indicator for ischemic cerebral vascular diseases. Finally, the relationship between high coagulation and acute cerebral vascular disease was discussed.

Iron overload is found clinically in such conditions as hemochromatosis and sideroblastic anemia, and after long term repeated transfusion in aplastic anemia. An animal model of iron overload was successfully developed in rats and rabbits by repeated intraperitoneal injections of ferric nitrilotriacetate (Fe3+-NTA). This procedure induced a diabetic state with hyperglycemia, ketonemia, glycosuria and ketonuria. Blood venesection on these rats reduced the iron load in the liver and pancreas, and ameliorated the general diabetic symptoms. A single injection of Fe3+-NTA in rats induced a temporary elevation in plasma iron concentration, lipid peroxidation in the perfused liver homogenate expressed by malondialdehyde (MDA) formation, blood GOT, GPT, ALP and gamma-GTP sequentially. Fe3+-NTA uptake in the liver caused membrane lipid peroxidation, and subsequently produced a transit liberation of liver cell enzymes, although the incorporated liver Fe3+-NTA was only 1% of the injected dosage (7.5 mg iron/kg BW) at 3 hr after injection. The direct toxic effect of Fe3+-NTA to living cells was examined using cultured normal rat liver parenchymal cells (RL-34). Marked cytolysis was found in cells exposed to more than 25 micrograms of iron through Fe3+-NTA/ml. At 50 micrograms iron of Fe3+-NTA/ml, most cells were lethally injured and the remaining cells were piled up and aggregated at 15 days. They grew on soft agar culture, and when inoculated subcutaneously to five newly born rats a subcutaneous tumor developed in all animals within three weeks. Lung metastases were found in three of five inoculated rats. A spin trapping technique with electron spin resonance (ESR) on Fe3+-NTA employing 5, 5-dimethyl-l-pyrroline-N-oxide (DMPO) yielded a spin adduct with three doublets (DMPO-Z) which corresponded to singlet oxygen. By ESR in the presence of H2O2, the Fe3+-NTA solution strongly generated hydroxyl radical. The production of active oxygen species by Fe3+-NTA solution may explain the toxicity and carcinogenicity of Fe3+-NTA. The majority of stainable iron in the iron overloaded tissue was hemosiderin (Hs). We tried to purify the Hs from multi-transfused human spleen by the method of Weir et al. The purified Hs did not show a DMPO-OH adducts in the presence of H2O2 and DMPO on ESR measurement. The Hs iron was solubilized with several biological ligands in an acidic state in the presence of a reducing reagent like glutathione. Solubilized Hs iron produced iron chelate complexes which resulted in OH radicals production in the presence of H2O2 in acidic conditions below pH 5.5.(ABSTRACT TRUNCATED AT 400 WORDS)

Human platelet lysates contained potent mitogenic activities for MCF-7 human breast-cancer cells in serum-free-defined media. Because these activities were not replaced by known platelet mitogens, such as platelet-derived growth factor or transforming growth factor beta, we sought to identify the breast cancer cell mitogens by purification and N alpha amino-acid sequencing. Acetic acid extracts of outdated human platelets were concentrated by ammonium sulfate precipitation and fractionated on Sephadex G-50 and Bio-Gel P-10 columns in 0.5 mol/L acetic acid. Two major activities were resolved by molecular sieve methods and fractionated further by reverse-phase high-performance liquid chromatography (HPLC). Purifications (70,000 to 870,000-fold) were accomplished yielding mol wt 7,400 products that were homogeneous as determined by iodination, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and autoradiography. The factors were identified as insulinlike growth factor I (IGF-I) and II (IGF-II) and truncated IGF-I by N alpha amino acid microsequencing. In dose-response experiments, platelet-derived IGF-I and IGF-II promoted multiple divisions of the MCF-7 cells with ED50 values of 12 and 100 pg/mL, respectively. The specific activities and other bioassay characteristics of platelet-derived IGF-I and IGF-II were similar to those of recombinant-produced human growth factors. This is the first report of the purification of insulinlike growth factors from human platelet lysates.

A complementary DNA library from MCF-7 cells was screened using 32P-cDNA derived from a breast carcinoma and from normal breast tissue. From 10(5) plaques (20% of library) we obtained a clone (Md2) which was differentially expressed in the carcinoma. The distribution of its corresponding transcript of 6-700 nucleotides was examined in normal and neoplastic cells, by filter and in situ hybridisation. We observed localisation of 35S-Md2 to the tumour cells of breast cancers with no significant reaction over stromal or vascular elements or on normal ductal epithelia. M13 sequencing showed Md2 to be 250 nucleotides in length, of which 197 were homologous to the 3'-untranslated region and a short open reading frame of the pS2 gene (Masiakowski et al., 1982). Md2 mRNA was found principally in breast carcinoma cell lines and tumours, with low levels in benign breast disease and no expression in non-breast squamous cell lines. Approximately 43% (23/54) of carcinomas contained this mRNA (varying from + to + + + + level); it was present in 20/38 (53%) of ER positive carcinomas compared to 3/16 (19%) of ER negative carcinomas. In 21 patients who had undergone primary endocrine therapy for recurrent disease expression of Md2 in the primary tumour correlated with the subsequent response to treatment (P = 0.041) and was of similar predictive value as ER status. Both tests correctly predicted outcome in about 76% of cases.

We examined the anticoagulant effects of phosphotungstate (PTA). PTA inhibited factors IIa and Xa activity only in the presence of antithrombin III (ATIII). The inhibitory effect of PTA on IIa was much smaller than that on Xa. When PTA was added to heparin (Hep), the inhibitory effect of Hep on IIa was reduced. As a result of charge interaction, PTA showed an inhibitory effect on anion transport activity of the erythrocyte, a potent salting-in effect and a metachromatic reaction on toluidine blue (TolB). Silicotungstate (STA) showed almost the same results as PTA. These effects of PTA and STA were not replaced by their constituents, tungstate, silicate and phosphate, but may arise from their high anionic valency.

Studies of radioiodinated antithrombin III kinetic behavior in vivo have shown that a pool of this protein partitions into a vascular compartment that could be the result of antithrombin III interaction with heparin-related glycosaminoglycans present on the vessel wall (J. Clin. Invest. 74, 191-191, 1984). As this partitioning was demonstrated by the rapid initial clearance of the labeled antithrombin III, new studies were performed to determine the effect on this clearance of large doses of intravenously administered heparin. In addition, as previous studies had shown unequal clearance rates for tracer-labeled antithrombin III isoforms differing in affinity for heparin, the effect of heparin treatment was assessed for each isoform. Comparison of data from heparin-treated and control animals demonstrated that heparin markedly decreased the clearance rates for each of the *I-labeled antithrombin III isoforms. Heparin also abolished the difference in *I-antithrombin III isoform plasma-clearance rates, and this effect rapidly disappeared after treatment was discontinued. Inhibition by heparin of the initial clearance of *I-labeled ATIII isoforms is the first direct evidence from in vivo studies for the notion that the pool of antithrombin III which is in rapid equilibrium with the plasma pool is, at least in part, the result of the interaction of antithrombin III with vessel wall heparin-related glycosaminoglycans.