K252a, a new inhibitor of protein kinase C, concomitantly inhibits 40K protein phosphorylation and serotonin secretion in a phorbol ester-stimulated platelets

K252a isolated from microbial origin was found to potently inhibit protein kinase C in vitro (1). This agent inhibits phosphorylation of 40,000 dalton protein (40K protein) induced by 12-0-tetradecanoylphorbol-13-acetate(TPA) in intact rabbit platelets. This indicates that K252a exhibits the inhibition of protein kinase C in intact cells. The serotonin secretion induced by TPA was inhibited by K252a at nearly equal concentrations required to inhibit the phosphorylation of 40K protein. This provides the evidence to support the cause-effect relationship between the protein phosphorylation and the secretion in TPA-stimulated platelets.     

Immunohistochemical studies on peptide- and amine-containing endocrine cells and nerves in the gut and the rectal gland of the ratfish Chimaera monstrosa

Summary The occurrence and distribution of endocrine cells and nerves were immunohistochemically demonstrated in the gut and rectal gland of the ratfish Chimaera monstrosa (Holocephala). The epithelium of the gut mucosa revealed open-type endocrine cells exhibiting immunoreactivity for serotonin (5HT), gastrin/cholecystokinin (CCK), pancreatic polypeptide (PP)/FMRFamide, somatostatin, glucagon, substance P or gastrin-releasing peptide (GRP). The rectum contained a large number of closed-type endocrine cells in the basal layer of its stratified epithelium; the majority contained 5HT- and GRP-like immunoreactivity in the same cytoplasm, whereas others were immunoreactive for substance P. The rectal gland revealed closed-type endocrine cells located in the collecting duct epithelium. Most of these contained substance P-like immunoreactivity, although some reacted either to antibody against somatostatin or against 5HT. Four types of nerves were identified in the gut and the rectal gland. The nerve cells and fibers that were immunoreactive for vasoactive intestinal peptide (VIP) and GRP formed dense plexuses in the lamina propria, submucosa and muscular layer of the gut and rectal gland. A sparse network of gastrin- and 5HT-immunoreactive nerve fibers was found in the mucosa and the muscular layer of the gut. The present study demonstrated for the first time the occurrence of the closed-type endocrine cells in the mucosa of the rectum and rectal gland of the ratfish. These abundant cells presumably secrete 5HT and/or peptides in response to mechanical stimuli in the gut and the rectal gland. The peptide-containing nerves may be involved in the regulation of secretion by the rectal gland.     

Functional and phenotypic analyses of interleukin 2-activated tumor-infiltrating lymphocytes

The tumor-infiltrating lymphocytes (TILs) were cultured with interleukin 2 (IL-2) to induce the activated killer cells possessing autologous tumor-killing activity, and analysed their cell surface phenotypes and assessed anti-tumor killing activity. Furthermore, the activated TILs were transferred into 7 patients adoptively resulting in complete remission in a patient with pancreatic cancer and partial remission in another patient with gastric cancer.The cytotoxic activities of activated TILs at 3 weeks-incubation was 72 ± 15, 42 ± 26, 27 ± 21 and 25 ± 15% against K562, Daudi, KATO-III and autologous tumor, respectively. The negative selection method, indicated that the killer cells recognizing autologous tumor cells consisted of CD4- or CD8-positive T lymphocytes and CD16- or CD56-positive natural killer cells. The activated TILs could not only lyse cultured tumor cell lines, but also autologous tumor cells.     

Light and electron microscopic studies on experimental nocardia-toxicosis in mice

An exotoxin (HS-6) produced by Nocardia otitidiscaviarum isolated from certain lesions of cutaneous nocardiosis of a male 82-year-old patient induced severe injuries in the pancreas, liver, stomach, small intestine, heart, thymus and kidney of male ICR mice. Mice given Nocardia-free preparation of HS-6 at a dose of 1 mg/kg of body weight developed several autophagic vacuoles in the pancreas and liver within 20 min after the i.p. injection. Thereafter, the autophagic vacuoles increased in number and size with time. About 24 hr after the administration of HS-6, the liver showed marked accumulation of fat droplets in the cytoplasm of the hepatocytes. Although they contained abundant autophagic vacuoles in the regions of RER, there were no lipomatoses in the acinar cells of the pancreas, those of the chief cells and smooth muscle cells of the stomach, Paneth cells, goblet cells, smooth muscle cells of the small intestine, and plasma cells in the digestive tract. Biochemical examinations revealed that HS-6 had no significant effect on the protein synthesis of reticulocytes. Inoculation of the Nocardia into the mouse peritoneal cavities caused marked granulomatoses in the pancreas, liver and regional lymph nodes, but did not develop autophagic vacuoles in RER regions of these organs.     

The promotive effect of interleukin 4 with interleukin 2 in the proliferation of tumor-infiltrating lymphocytes from patients with malignant tumor

In adoptive immunotherapy, the number of effector cells is one of the major factors relating to the therapeutic efficacy. We demonstrated that tumor-infiltrating lymphocytes (TILs) were stimulated to proliferate by incubation with interleukin 2 (IL-2) plus interleukin 4 (IL-4). TILs cultured with IL-2 plus IL-4 increased 3.1-fold more than TILs cultured with IL-2 alone. However, IL-4 did not alter the cytotoxic activity of TILs against autologous tumor cells and established tumor cell lines. It is suggested that IL-2 receptor is related to the mechanism of the proliferation of activated TILs cultured by combination with IL-2 and IL-4. Thus, the combination of IL-2 and IL-4 may increase the efficacy of adoptive immunotherapy using activated TILs.     

Effects of sulfur dioxide and ozone on intact leaves and isolated mesophyll cells of groundnut plants (Arachis hypogaea L.)

Difference between effects of sulfur dioxide (SO₂) and ozone (O₃) on groundnut plants (Arachis hypogaea L.) was studied by use of an exposure system of enzymatically-isolated mesophyll cells. SO₂ inhibited photosynthesis of intact groundnut leaves but induced no visible injury on leaves. SO₂ also inhibited photosynthesis of isolated mesophyll cells but did not kill the cells, suggesting that SO₂ inhibits photosynthesis by attacking rather specifically the photosynthetic apparatus in chloroplasts. O₃ inhibited photosynthesis of intact leaves and at the same time induced visible injury corresponding to the extent of photosynthesis inhibition. O₃ also inhibited photosynthesis of isolated mesophyll cells and killed the cells to the extent corresponding to photosynthesis inhibition, suggesting that O₃ inhibits photosynthesis not directly by attacking the photosynthetic apparatus but indirectly by killing cells. Since the response of intact leaves to each pollutant resembled that of isolated mesophyll cells, the difference between responses of intact leaves to both pollutants may considerably reflect that of mesophyll cells.     

Mouse Offspring Derived from Fetal Ovaries or Reaggregates Which were Cultured and Transplanted into Adult Females

Primordial germ cells (PGCs) and gonia could be promising novel targets and vehicles for manipulation of the mammalian germ line. To make such manipulation a practical possibility, PGCs or gonia must be allowed to produce gametes and offspring after they were isolated from embryos and manipulated in culture. As the first step to develop such research strategy, we obtained offspring from mouse oogonia which were isolated from embryonic ovaries and cultured as dispersed cells before transplantation into female mice as reaggregates.     

Superoxide dismutases enhance the rate of autoxidation of 3-hydroxyanthranilic acid

The autoxidation of 3-hydroxyanthranilate to cinnabarinate at 37 degrees C and at pH 7.4 is hastened by superoxide dismutase (SOD). The Cu,Zn-containing enzyme from bovine erythrocytes and the Mn-containing enzyme from Escherichia coli were equally effective in this regard; whereas the H2O2-inactivated Cu,Zn enzyme was ineffective. Catalase appears to augment the effect of superoxide dismutase, because it prevents the bleaching of cinnabarinate by H2O2. It follows that O2-, which is a product of the autoxidation, slows the net autoxidation by engaging in back reactions and that SOD increases the rate of autoxidation by removal of O2- and thus by prevention of these back reactions.     

Late Quaternary Environmental and Human Impacts on the Mitochondrial DNA Diversity of Four Commensal Rodents in Myanmar

Journal of Mammalian Evolution - We addressed the spatiotemporal characteristics of four commensal rodent species occurring in Myanmar in comparison with other areas of the Indo-Malayan region. We...     

Aldehyde reductase gene expression by lipid peroxidation end products,MDA and HNE

Membrane lipid peroxidation results in the production of a variety of aldehydic compounds that play a significant role in aging, drug toxicity and the pathogenesis of a number of human diseases, such as atherosclerosis and cancer. Increased lipid peroxidation and reduced antioxidant status may also contribute to the development of diabetic complications. This study reports that lipid peroxidation end products such as malondialdehyde (MDA) and 4-hydroxynonenal (HNE) induce aldehyde reductase (ALR) gene expression. MDA and HNE induce an increase in intracellular peroxide levels; N-Acetyl-L-cysteine (NAC) suppressed MDA- and HNE-induced ALR gene expression. These results indicate that increased levels of intracellular peroxides by MDA and HNE might be involved in the upregulation of ALR.