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The changes of myoglobin localization in the skeletal muscle cells in Duchenne muscular dystrophy (DMD), myotonic dystrophy (MyD), and amyotrophic lateral sclerosis (ALS) were studied by immunohistochemistry and immunoelectron microscopy. In normal skeletal muscle cells, myoglobin was found in I band, Z line, mitochondrial outer membrane and inner membrane structures of sarcoplasmic reticulum and T tube. In contrast, the myoglobin staining of the I bands in degenerative muscle-cells of DMD and MyD was found rather diminished, and A bands, intraluminal spaces of the inner membrane system and intermyofibrillar spaces were myoglobin positive. Moreover, the I band of a myofibril which slipped out of other normally arranged myofibrils showed no myoglobin staining, but the distended intermyofibrillar spaces adjacent to the slipped myofibril showed a definite staining. In addition, there were dilated sarcoplasmic reticula showing the staining in their lumina, but the I bands neighboring them revealed a diminished staining. In DMD muscle, no staining was found in opaque fibers and some small sized fibers. In ALS muscle, myoglobin was usually positive in the I bands, but the small angulated fibers showed a variable staining. In the target fibers, central zone was not stained but intermediate zone showed altered myoglobin localization. These data indicate that (1) myoglobin localization in the muscle cells varies depending on the sorts of diseases and the grades of muscle cell degeneration, (2) myoglobin in dystrophic muscles fluxes from the muscle cells to extracellular spaces through the dilated sarcoplasmic reticula, T tubes and intermyofibrillar spaces, and (3) in DMD muscle, myoglobin also fluxes directly through the deteriorated plasma membrane in opaque fibers or through the plasma membrane altered due to dystrophin deficiency.

Reduction of the immunogenicity of the tissue by tissue culture has been a controversial concept in transplantation immunology. In the present study, isolated islets were cultured prior to allotransplantation. The obtained results were compared in comparison with the results of the non-cultured islet allotransplantation group. Two kinds of rats differing from each other in histocompatibility antigen were used. WKA rats ( RT1k ) were donors, and LEJ rats ( RT1j ) recipients. No immunosuppressive agents were given. About 500 isolated islets of the donors were transplanted to the spleen of the recipients with streptozotocin induced diabetes mellitus. Although the mean survival time of non-cultured islet was 12.2 +/- 4.3 days, that of 7-day cultured islet increased significantly to 26.4 +/- 4.8 days. The response of the lymphocytes to the islets was also examined by mixed lymphocyte-islet culture. Response of lymphocytes to non-cultured islet was compared with that of lymphocytes to 7-day cultured islets. The response of lymphocytes to the 7-day cultured islets was significantly decreased. These results suggested that the cultured islet prolongs survival time and islet culture diminish the concentration or availability of stimulatory antigens on the cell surface membranes.

When bovine serum fraction V powder, which contains 98-99% albumin, is incubated with rat liver microsomes, the glutathione S-transferase activity is stimulated 3-fold. The fraction V stimulates the transferase activity even in microsomes pretreated with N-ethylmaleimide. There is no such stimulating activity in protein fractions other than fraction V. The corresponding cytosolic enzyme activity is not changed by fraction V powder or by N-ethylmaleimide. Neither treatment with charcoal nor heating in boiling water for 5 min can remove the stimulating activity from fraction V.

Glutathione disulfide stimulates the activity of rat liver microsomal glutathione S-transferase 2-fold after incubation at 25 degrees C for 10 min. When the microsomes were incubated with the disulfide for over 20 min, the transferase activity increased to the same extent as in the case of N-ethylmaleimide (6-fold). Even in the presence of reduced glutathione, some enhancement of the transferase activity was observed. The data presented here are evidence that increase in glutathione disulfide level, e.g. by lipid peroxidation, on endoplasmic reticulum causes the upregulation of microsomal glutathione S-transferase activity.

Various kinds of calmodulin-interacting agents have been proved to suppress tumor promotion in vivo. In this study, we further demonstrate that flunarizine and dehydroepiandrosterone, which are proved to interact with calmodulin, showed antitumor-promoting activity in two-stage carcinogenesis of mouse skin. These results indicate that Ca2+/-calmodulin system, may play an important role in tumor promotion.

Effects of SAMe on disturbances in trained hand movement tasks or a trained delayed response task after lesion in unilateral motor cortex (hand area) or bilateral dorsolateral prefrontal cortices were studied in the monkey. Following lesion, hand movement tasks or delayed response tasks were disturbed moderately or severely for one week to several months depending on the extent of lesion or nature of task. Although treatment with small doses of SAMe (10 mg/kg/day, i.m.) had no effect, treatment with moderate doses (SAMe, 20 or 30 mg/kg, i.m.) reduced impairment and promoted recovery from both disturbances. Even in the chronic stage (76-140 days after operation), SAMe (30 mg/kg/day, i.m.) facilitated recovery from delayed response deficits. Histological findings in the acute stage after cortical lesion in rats showed that SAMe (50 mg/kg/day, s.c.) augmented infiltration of activated phagocytic macrophages in lesioned sites. Data suggest that SAMe improves recovery from behavioral and histological disturbances due to brain damages.

Quercetin markedly suppressed the promoting effect of teleocidin on skin tumor formation in mice initiated with 7,12-dimethylbenz[a]anthracene. This activity of quercetin may have some bearing on the fact that quercetin is not carcinogenic despite showing mutagenicity.

3,7,11,15-Tetramethyl-2,4,6,10,14-hexadecapentaenoic acid (E5166), a synthetic analog of retinoic acid, increased 2-deoxy-D-glucose (2DG) uptake in a dose and time-dependent manner in mouse fibroblasts, Swiss 3T3 cells. Kinetic analysis of 2DG uptake showed that the Vmax for 2DG uptake by E5166-treated cells was greater than that of the control, while the Km values were essentially the same. Most of the E5166-stimulated 2DG uptake was suppressed by cycloheximide, although part of the stimulation always remained despite of the cycloheximide treatment. These results suggest that E5166-induced stimulation of 2DG uptake is due to the increase in the synthesis and recycle of hexose transporters (carriers) in Swiss 3T3 cells.

Oligodeoxyribonuclotides containing N6-methoxyadenine (mo6A), a promutagenic base, were synthesized. The Tm values and thermodynamic parameters for double strand formation of d(CCTGGTAmo6ACAGGTCC) have been measured. The order of the base-pair stability was A-T greater than mo6A-C approximately equal to mo6A-T greater than A-C.

Staurosporine, an antitumor-promoting agent, suppressed phorbol ester-enhanced phospholipid synthesis. The inhibitory effect of staurosporine was found to be dominant in the synthesis of phosphatidylcholine and phosphatidylethanolamine. The manner of this inhibitory action by staurosporine was similar to that of various kinds of antitumor-promoting agents, which have the ability to interact with Ca2(+)-calmodulin complex, although the effective dose of staurosporine was 1,000 times lower than these calmodulin-interacting agents. Furthermore, staurosporine was proved to interact directly with Ca2(+)-calmodulin complex. Thus, it is possible that staurosporine showed inhibitory effect on phospholipid metabolism via the modulation of Ca2(+)-calmodulin system.

A possible mechanism of antitumor-promoting activity of alpha-2,7,11-cembratriene-4,6-diol (alpha-CBT) was studied. alpha-CBT inhibited the 32Pi incorporation into phospholipids of HeLa cells stimulated by 12-O-tetradecanoylphorbol-13-acetate (TPA). In contrast to the property to interact with calmodulin of many other antitumor-promoting agents, which were proved to inhibit TPA-stimulated 32Pi incorporation into phospholipids, alpha-CBT did not show any interaction with calmodulin; i.e., the fluorescence of N-phenyl-1-naphthylamine enhanced by binding with Ca2+-calmodulin was not influenced by treatment with alpha-CBT. TPA-stimulated phosphorylation of 47-kilodalton protein, which is phosphorylated by protein kinase C in human platelets, was found to be inhibited by alpha-CBT. However, the specific binding of 3H-TPA to mouse epidermal particulate fraction was not inhibited by treatment with alpha-CBT. These results suggest that alpha-CBT inhibits the activity of protein kinase C by another mode of action rather than the effect on its receptor site, and that this action and calmodulin-independent inhibitory effect on phospholipid metabolism of alpha-CBT may play a certain role in its antitumor-promoting activity in vivo.

The Lugol dye spraying method in endoscopy is compared with the usual endoscopy. Its diagnostic values are discussed from the endoscopical and histological point of views. Normal esophageal epithelium is stained brown or dark brown with 5% of Lugol's solution, and shows a "silk-crape" like surface appearance when observed close up. The cancerous or inflammatory epithelium of the stomach and esophagus do not stain. With the sue of directed biopsy this reveals the usefulness of this method, specially for finding small esophagel cancer and for accurately delineating the extent of a cancer. Furthermore, esophagitis is easier to diagnose. As healing occurs, the staining characteristic return. Esophageal epithelium capacity for staining with Lugol's solution seems to be related to the glycogen content of the squamous epithelium.

Glycyrrhetic acid suppressed tumor promoter-induced effects in vitro, such as stimulation of 32Pi-incorporation into phospholipids of cultured cells and down-regulation of the epidermal growth factor receptor. Glycyrrhetic acid inhibited the promoting activity of both 12-O-tetradecanoylphorbol-13-acetate (TPA) and teleocidin on skin tumor formation in mice initiated with 7,12-dimethylbenz[a]anthracene (DMBA). The percentage of tumor-bearing mice in the group treated with DMBA plus teleocidin was 88% at week 18, whereas that in the group treated with DMBA plus teleocidin and glycyrrhetic acid (10 mumol/painting) was 6%. Similarly, the percentage of tumor-bearing mice of the group treated with DMBA plus TPA was 97% at week 20, whereas that of the group treated with DMBA plus TPA and glycyrrhetic acid was 40%. Therefore, glycyrrhetic acid was proved to inhibit the activity of two different tumor promoters, teleocidin and TPA, in mouse skin.

Human tumor degenerating factor (TDF) activity was inhibited by the addition of more than 8 micrograms/ml of fibronectin. The crude TDF preparation also inhibited the activity of TDF. The inhibitor of TDF activity was isolated from the crude TDF preparation by gelatin-Sepharose chromatography. Furthermore, this inhibitor was isolated from the fetal bovine serum (FBS), which is used for the production of TDF, by the same chromatography. Since the inhibitors from TDF preparation and the FBS showed the cross reaction with fibronectin by micro-Ouchterlony using anti-fibronectin serum, it was suggested that a part of the inhibitors was identical to fibronectin.

In 14 patients with left atrial thrombi, coronary arteriography and real time, two-dimensional echocardiography were performed and compared with the surgical findings. Age of the patients with left atrial thrombi was relatively high, and their hemodynamic findings were severe. By the combined use of coronary arteriography and real time two-dimensional echocardiography, the prediction of left atrial thrombi was possible in 93%. Coronary arteriography provided a useful information as to the location of thrombi, especially in the left atrial appendage, while the size and shape of thrombi were not predictable by this method. On the contrary, two-dimensional echocardiography was useful to determine the size and shape of the thrombi.

In order to achieve simultaneous removal of gaseous and particulate room airpollutants, the following two approaches were taken; 1) use of activated carbon fiber (ACF) filter, focusing on the improvement of its particle collection efficiency by using electrostatic charge caused by surface modification with chemicals and enhancement of adsorption capacity by chemical impregnation, 2) conversion of gaseous components to particles so as to collect them by air filters. It was shown that 1) the immersion of ACF filter in hydrogenperoxide solution brings electrostatic charge on the fibers, which markedly increases the collection efficiency for charged particles, 2) the impregnation of aniline is very effective for the adsorption of acetaldehyde, and 3) by the use of corona discharge, acetaldehyde is decomposed to other gaseous matters, but some olefin compounds in cigarette smoke are converted to particles via a reaction with ozone.

This article represents the proceedings of a workshop at the 2000 ISBRA Meeting in Yokohama, Japan. The presentations were (1) Phenotypic alteration of myofibroblast during ethanol-induced pancreatic injury: its relation to bFGF, by Masahiko Nakamura, Kanji Tsuchimoto, and Hiromasa Ishii; (2) Activation of pancreatic stellate cells in pancreatic fibrosis, by Paul S. Haber, Gregory W. Keogh, Minoti V. Apte, Corey S. Moran, Nancy L. Stewart, Darrell H.G. Crawford, Romano C. Pirola, Geoffrey W. McCaughan, Grant A. Ramm, and Jeremy S. Wilson; (3) Pancreatic blood flow and pancreatic enzyme secretion on acute ethanol infusion in anesthetized RAT, by H. Nishino, M. Kohno, R. Aizawa, and N. Tajima; (4) Genotype difference of alcohol-metabolizing enzymes in relation to chronic alcoholic pancreatitis between the alcoholic in the National Institute on Alcoholism and patients in other general hospitals in Japan, by K. Maruyama, H. Takahashi, S. Matsushita, K. Okuyama, A. Yokoyama, Y. Nakamura, K. Shirakura, and H. Ishii; and (5) Alcohol consumption and incidence of type 2 diabetes, by Katherine M. Conigrave, B. Frank Hu, Carlos A. Camargo Jr, Meir J. Stampfer, Walter C. Willett, and Eric B. Rimm.