Effects of gastrectomy on insulin secretion in rats

To examine the relative importance of the stomach for the enteroinsular axis, the portal insulin secretion was measured in the rats with gastrectomy, after intraduodenal (I.D.) infusion of 0.5 g/kg glucose and after intravenous (I.V.) infusion of the same deal of glucose, respectively. Portal plasma gastrin was decreased from 100 pg/ml to 5 pg/ml by gastrectomy. Blood sugar level after I.D. and I.V. infusion of glucose in the rats with gastrectomy was similar to controls. Insulin release to I.D. infusion of glucose was slightly lower at 30 minutes in the gastrectomized rats compared with controls, while insulin secretion to I.V. infusion of glucose was similar to controls. These results suggest that endogenous gastrin has no insulinotropic effect and that the stomach has no direct effect on glucose-induced insulin release.

Cholinergic effect of 2-deoxy-D-glucose on plasma glucagon levels in conscious rats

The present study was conducted to investigate how the in vivo glucagon secretory response to 2-deoxy-D-glucose relates to control of nervous system. Plasma glucagon levels in the rat were significantly elevated by 2-deoxy-D-glucose administration (40 mg/100 g body weight). That response was suppressed by hexamethonium, a nicotinic ganglionic blocker. By contrast, treatment with atropine (5 mg/100 g body weight), a muscarinic antagonist, had no effect on glucagon secretion due to the same dose of the deoxysugar, whereas the drug totally inhibited the response to a lower concentration of the deoxysugar. Administration of 2-deoxy-D-glucose significantly elevated plasma epinephrine levels, and it was suppressed by hexamethonium. Plasma insulin levels were not so changed despite hyperglycaemia. In conclusion, the present study suggests that 2-deoxy-D-glucose may act on cholinergic nerve system to stimulate the release of glucagon and epinephrine.

[A case of perirenal encysted hematoma secondary to renal cell adenocarcinoma]

Herein we report a case of perirenal encysted hematoma secondary to renal cell adenocarcinoma. A 57-year-old woman was hospitalized because of a palpable mass in the left flank. She had had an episode of left flank pain. X-ray studies demonstrated a tumor in the left kidney and a large cystic mass beneath the left kidney. The cyst was excised by nephrectomy. Histological examination of the large cyst revealed perirenal encysted hematoma secondary to renal cell adenocarcinoma. Six months postoperatively, she is now free from left lumbar pain, and alive with lung and liver metastasis.

Elevation of plasma triglyceride levels due to 2-deoxy-D-glucose in conscious rats

Hypertriglyceridemia due to 2-deoxy-D-glucose administration was observed in conscious rats. Plasma triglyceride levels were elevated dose-dependently 2 or 3 hrs after administration of 2-deoxy-D-glucose (5-40 mg/100 g body weight). Prior to the rises in triglyceride, plasma epinephrine levels were elevated rapidly, whereas plasma insulin was not increased depspite continuous hyperglycemia. Elevation of plasma triglyceride was suppressed by addition of phentolamine, whereby insulin release was remarkably enhanced. Plasma lipoprotein lipase release by heparin infusion was significantly suppressed 2 hr after 2-deoxy-D-glucose administration. In conclusion, it is suggested that the hypertriglyceridemic effect of 2-deoxy-D-glucose may be mediated by decreased clearance of endogeneous lipoprotein particles (mostly chylomicrons) attributable to a lowered lipoprotein lipase activity.

Clear cell carcinoma of the ovary with colony-stimulating-factor production. Occurrence of marked granulocytosis in a patient and nude mice

A case of clear cell carcinoma of the ovary with colony-stimulating-factor (CSF) production is presented. Granulocytosis (54,200/mm3) of unknown cause was observed in a patient at the terminal stage of the clinical course. This tumor was successfully heterotransplanted into athymic nude mice, and transplantable tumor line was designated as OCL-1. OCL-1 tumor reproduced granulocytosis up to 640,000/mm3 in nude mice, and CSF production was demonstrated by colony-forming assay using tumor extract and mouse bone marrow cells in vitro. This is the first report that describes the case of CSF-producing clear cell carcinoma of the ovary and its heterotransplantation in nude mice.

Argyrophil cells in the urachal epithelium and urachal adenocarcinoma

Urachal adenocarcinoma, normal urachus, and urinary bladder were studied by histochemical methods and electron microscopy. Many argyrophil cells were found in urachal adenocarcinoma and urachal epithelium. Autofluorescence and immunoperoxidase examinations showed that the argyrophil cells possessed serotonin, glucagon, and secretin. Some of the carcinoma cells and urachal epithelial cells contained fairly large amount of mucosubstances. On the other hand, only a few argyrophil cells and very weakly PAS positive cells were observed in the urinary bladder mucosa. This study showed that there were close similarities in the histochemical and electron microscopical features between the urachal carcinoma and urachal epithelium, and suggested that the undifferentiated stem cells were able to differentiate to both glandular and endocrine cells.

99mTc-DL-Homocysteine, a potential tumor imaging agent

The usefulness of 99mTc-labeled DL-homocysteine as a tumor imaging agent was further supported by high concentration distribution into the tumors of human lung or stomach tumor-bearing nude mice.

Natural killer-interferon system in patients with preleukaemic states

The natural killer (NK)-interferon (IFN) system was investigated in patients with preleukaemic states. Endogenous NK cell activity was markedly reduced in all 12 patients studied. No significant correlation was observed between the activity of NK cells and the percentage of blast cells in the peripheral blood or bone marrow. The frequency of large granular lymphocytes (LGL) in lymphocytes of the peripheral blood was not reduced in most patients. The percentage of target binding cells in patients was essentially the same as that in normal controls, and the activity of NK cells from normal donors was not affected by the coexistence of mononuclear cells obtained from the peripheral blood of patients. Furthermore, the alpha-IFN production in response to HeLa cells persistently infected with measles virus was reduced in all patients studied, except for one case with acquired idiopathic sideroblastic anaemia. The augmented activity of NK cells induced by alpha-IFN was variable, but remained at lower levels than the endogenous activity of NK cells in normal controls. These findings suggest that not only the intrinsic defect and reduced number of NK cells but also the dysfunction of the NK-IFN system may be responsible for the reduced activity of NK cells in patients with preleukaemic states.

Two-dimensional peptide mapping by polyacrylamide-gel electrophoresis with limited proteolysis in SDS

The peptide mapping method described by Cleveland, et al. (1) was improved to a two-dimensional analysis applicable to minute amounts (less than 0.5 microgram) of proteins. Radioiodinated proteins for analysis were purified by electrophoretic elution of the proteins from polyacrylamide gels into buffer containing 0.1% sodium dodecyl sulfate. The proteins were digested enzymatically in the presence of 0.1% sodium dodecyl sulfate and an excess of nonlabeled bovine serum albumin (0.2 mg/ml) relative to labeled substrate in order to attain reproducibility by maintaining a consistent substrate concentration among different samples. The peptides of these limited proteolytic products were resolved by two-dimensional polyacrylamide gel electrophoresis (isoelectric focusing followed by SDS-gels). The resulting 2D-peptide maps of murine and bovine albumin and a murine lymphocyte membrane protein, Tp100, showed excellent resolution and reproducibility.

Tumor detection with some 99mTc-labeled S-containing amino acids

99mTc-labeled L-cysteine, DL-homocysteine, and S-carbamyl-L-cysteine were prepared and tested for effectiveness in gamma camera imaging and for bioradiodistribution in mice bearing Ehrlich solid tumors. Among these labeled compounds, 99mTc-DL-homocysteine seems most promising for the nuclear medical imaging of tumors.

Biological evaluation of radiolabeled D-methionine as a parent compound in potential nuclear imaging

Based on the high radioactivity uptake of some 14C-labeled D-amino acids in tumors and pancreas of mice, this investigation was undertaken to ascertain possible usefulness of radioactive D-methionine as a nuclear imaging agent. Radioactivity derived from D-[3,4-14C]-methionine in Ehrlich solid tumor was approximately three times higher than that from the L-isomer, but was the same as for mouse pancreas. Excretion rate of the radioactivity of D-[14C]-methionine into urine was approximately two times faster than that of the L-isomer. As compared with two potential imaging agents, 1-aminocyclopentane-1-carboxylic acid and alpha-aminoisobutyric acid, D-methionine showed almost the same radioactivity biodistribution in tumor and pancreas. These results suggest potential for D-methionine as a mother compound for use in tumor and pancreas imaging.

Tumor hypoglycemia induced in nude mice by a heterotransplantable human ovarian carcinoma line (OCL-1)

Tumor hypoglycemia induced by a heterotransplantable human ovarian carcinoma line (OCL-1) was described. Plasma glucose decreased to 36 +/- 9 mg/dl (S.D.) at 8 to 12 weeks after the transplantation. Significant amounts of immunoreactive insulin and insulin-like active substance could not be detected in tumor tissues. Plasma immunoreactive insulin levels were low, and glucagon levels were high in OCL-1-bearing nude mice, compared with the control. Light- and electron-microscopically, tumor cells possessed large amounts of glycogen, and this finding was also biochemically confirmed. OCL-1 tumor showed high glycogen synthetase activity compared with other control tumors, while glycogen phosphorylase activity was the same level as other tumors. The high glycogen synthetase activity was considered to be the cause of glycogen accumulation in tumor cells. Hypoglycemia in OCL-1-bearing nude mice was considered to be caused by abnormal redistribution of glycogen, i.e., marked accumulation of glycogen in tumor tissues and depletion of glycogen in the host liver. This OCL-1 tumor-nude mice system was thought to be a good model for research on the mechanisms of tumor hypoglycemia occurring in cancer patients with nonpancreatic islet cell tumors.

Stimulating effects of inosine, uridine and glutamine on the tissue distribution of radioactive D-leucine in tumor bearing mice

This experiment was carried out in search for stimulators of the in vivo uptake of D- and L-leucine by tumor and pancreas for the possible application to gamma-emitter labeled amino acids in nuclear medical diagnosis. Inosine, uridine, and glutamine which are stimulators of the in vitro incorporation of radioactive L-amino acids into some tumor cells significantly enhanced the uptake of D-leucine into the pancreas, while in Ehrlich solid tumor only a little if any increase was observed. Of the compounds tested inosine showed the highest stimulation of pancreas uptake in the range of doses used, resulting in the best pancreas-to-liver concentration ratio, a factor of significant consideration for pancreas imaging. The uptake of L-leucine by the tumor and pancreas was little affected by these compounds.

Mixed mesodermal tumor of the ovary with carcinoembryonic antigen and alkaline phosphatase production. Histochemical, autoradiographic, and electron microscopic studies of heterotransplanted tumors in athymic nude mice

A mixed mesodermal tumor of the ovary with carcinoembryonic antigen (CEA) and alkaline phosphatase (ALP) production was serially heterotransplanted into nude mice. The original tumor was diagnosed as homologous tumor, with sarcomatous component consisting of nonspecific spindle-shaped cells. These features were basically retained in the transplanted tumors, including CEA and ALP production. But, heterologous, chondrocytic-differentiated foci were found in the tumors at the third and sixth passages. Transitional-type cells from sarcomatous to carcinomatous cells were sometimes found in the transplanted tumors by light and electron microscopy. Ciliated sarcomatous cells, which may also represent the epithelial differentiation of sarcomatous cells, were found in the tumors at first passage. The current results support the combination tumor theory, which means that both the carcinomatous and sarcomatous components are of common stem cell origin.

Analysis of normal and neoplastic lymphocyte surface-labeled proteins by two-dimensional polyacrylamide gel electrophoresis

Normal and neoplastic murine and human lymphocytes were surface-labeled by lactoperoxidase-catalyzed radioiodination, and the cell lysates were subjected to two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) analyses, combining isoelectric focusing in the first dimension and sodium dodecyl sulfate-PAGE (SDS-PAGE) in the second dimension. 2D-PAGE autoradiogram patterns were reproducible and reflected differences in cell types. A string of spots with a Mr of 100K was tentatively identified as a new T-cell marker (Tp100) which was present in all murine and human T cells examined including human T lymphomas. Murine and human B cells displayed markers characteristic to B cells of each species with some similarities between them. Human lymphomas and murine cell lines showed markers which were absent or only weakly visible in normal cells. Thus, 2D-PAGE analysis of lymphocyte surface proteins proved to be a method useful for searching for various markers.

Isolation and characterization of two thiol proteinase inhibitors of low molecular weight from newborn rat epidermis

Two low-molecular-weight thiol proteinase inhibitors, TPI(1) and TPI(2), were purified from newborn rat epidermis by homogenization and extraction at 37 degrees C, followed by lyophilization, Sephadex G-75 gel filtration and DEAE-cellulose column chromatography. Both purified inhibitors were shown to be homogeneous by polyacrylamide gel electrophoresis in the presence and absence of SDS. TPI(1) was more anionic than TPI(2), and the molecular weights of TPI(1) and TPI(2) were determined to be ca. 12,000 and 13,000, respectively. They were highly specific for thiol proteinase; TPI(1) was especially more effective than TPI(2) on the proteolytic activity of casein and hydrolytic activity of papain on authentic substrates, and a similar but lesser effect was detected for ficin. They inhibited the enzyme in a noncompetitive manner with inhibition constants of 6.01 X 10(-8) M and 4.57 X 10(-7) M for TPI(1) and TPI(2), respectively, calculated from the BAPA hydrolytic activity of papain. Both inhibitors were quite stable proteins as to heat and extreme pHs. The amino acid composition of TPI(1) and TPI(2) were slightly different from each other, and both inhibitors contained no cysteinyl or cytinyl residue and trptophanyl residue. From these results, TPI(1) and TPI(2) seem to be iso-inhibitors. The absorption and CD spectra of TPI(1) and TPI(2) in the near ultraviolet region indicated that the conformation in the vicinity of aromatic amino acid residues in TPI(1) was slightly different from that of TPI(2). The CD spectra of both inhibitors in the far ultraviolet region showed the presence of the beta turn structure in the protein moiety, suggesting some important roles of the beta turn of both inhibitors in the interaction with the thiol enzymes.

Suppressive effect of intragastric nutrients infusion on insulin release from perfused rat pancreas

Using the isolated and perfused rat pancreas preparations, we examined whether or not the direct transmission of signals from the gastro-duodenum to the pancreatic islets is existent. Pancreases were isolated en bloc with stomach and the proximal portion of duodenum and were perfused without recirculation. After perfusion with 5.5mM glucose in the perfusate for 40 minutes, 1 ml solution of the following nutrients (0.9% and 9% NaCl, 5% and 50% glucose, 5% and 50% fructose) was respectively infused into the stomach. And ten minutes after the infusion, the pancreas was perfused with 16.7 mM glucose for 20 minutes. Although the glucose-induced insulin release was similar to controls in the pancreas with intragastric infusion of 0.9% NaCl, 5% glucose, and 5% fructose, it was significantly lowered in the pancreas with intragastric infusion of 9% NaCl, 50% glucose, and 50% fructose. These results indicate that there is a direct transmission of some signals from the gastro-duodenum to the pancreatic islets through intragastric high osmolarity.

Secretory component and IgA in endometrial adenocarcinomas. An immunohistochemical study

The localization of secretory component (SC) and IgA was immunohistochemically studied in 6 normal endometrium and 55 endometrial adenocarcinomas including 34 well, 11 moderately and 10 poorly differentiated ones. In normal endometrium, SC localization was found in the cytoplasm of epithelial cells and luminal contents of the gland. IgA showed similar localization of SC. Secretory phase endometrium contained proportionally larger numbers of positive cells for SC and IgA than proliferative phase endometrium. SC localization was found in all cases of well and moderately differentiated carcinomas, while it was found only in 4 cases out of 10 poorly differentiated carcinomas. IgA localization was similar to that of SC and this condition was thought to reveal the binding of IgA to SC existing in the tumor cells. The present immunohistochemical study revealed that the staining intensity of SC well correlated with the histological grade of differentiation of the tumors.

On the denaturation of porcine erythrocyte catalase with alkali, urea, and guanidine hydrochloride in relation to its subunit structure

The dissociation of porcine erythrocyte catalase [EC 1.11.1.6] into subunits on denaturation with alkali, GuHCl and urea was investigated by following the changes in hydrodynamic properties, absorption and CD spectra in the Soret region and inactivation of the enzyme. It was found that dissociation proceeded in an "all or none" manner from the native tetramer (molecular weight, ca. 250,000) into identical 1/4-sized monomers (molecular weight, ca. 54,000 with alkali, 65,000 with urea and 71,000 with GuHCl) as estimated by ultracentrifugal analyses. On this dissociation, the sedimentation coefficient decreased from about 11S to 5.1 - 3.7S, and absorption spectra in the Soret region decreased to about 40% of the native level and showed a broad band around 365-375 nm and a shoulder around 415-420 nm; these changes were accompanied by complete loss of enzyme activity. The change in enzyme activity correlated well with that of absorption and CD spectra in the Soret region, depending on denaturation time, alkaline pH used and concentration of both denaturants. The reassociated catalase obtained by removing urea by dialysis was characterized by recovery of distinct CD bands in the Soret and near ultraviolet regions, although the partial refolding of alpha-helical conformation occurred without recovery of enzyme activity. These results indicate that the conformational changes and dissociation process of catalase into subunits can be monitored spectrophotometrically in relation to enzyme activity, and that subtle conformations near the heme groups and polypeptide backbone play an important role in maintaining full enzyme activity of the catalase molecule.