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N Kono

Publications and source records attributed to N Kono.

At least 145 records · Page 8Linked to original sources
PubMed1989

Presence of glucagon-(1-21)-Like immunoreactive substance in the dog small intestinal mucosa.

By using an antiserum (K291) specifically directed to the C-terminal of glucagon-(1-21)-peptide, we demonstrated the presence of glucagon-(1-21)-like immunoreactivity (G21-IR) in the dog intestine. G21-IR was found to be widely distributed throughout the small intestine and colon in parallel with the distribution of glucagon-like immunoreactivity (GLI), measured by N-terminal glucagon antiserum (OAL196). The subsequent analyses by gel filtration and three HPLC columns (reverse phase, ion exchange and further reverse phase columns) showed that G21-IR consisted of three main peaks, and the smallest molecular form of G21-IR is identical to glucagon-(1-21)-peptide.

Amino Acid Sequence↗
PubMed1989

Occurrence of bilirubin-IX beta in the gallbladder bile of eel, Anguilla japonica.

Bilirubin-IX beta isomer was detected in the bile of eel, Anguilla japonica, as evidenced by high-performance liquid chromatography (HPLC) analysis of free acid and its ethyl anthranilate diazo derivatives. Bilirubin-IX beta accounted for 16.7 +/- 6.0 (mean +/- S.D.) percent of the total bilirubins in the bile of 40 eels analysed, and the percentage was much higher than that reported in the biles of mammals.

Anguilla↗
PubMed1989

Clinical utility of somatosensory evoked potentials in diabetes mellitus.

The posterior tibial nerve and median nerve somatosensory evoked potentials (PTN-SEPs and MN-SEPs) were investigated in 34 patients with diabetes mellitus (DM). We measured the latency of the first positive cortical potential (the cortical P37) of PTN-SEPs and that of the first negative cortical potential (the cortical N18) and Erb's potential of MN-SEPs. In 18 patients (52.9%), the cortical P37 latency was more than 3 SD longer than normal in the tibial nerve. There were positive correlations between the latency of cortical P37 and the duration of DM and the motor nerve conduction velocity of the posterior tibial nerve. Sensory action potentials of the posterior tibial nerve were not detectable in 21 patients, though cortical P37 potential was unambiguously recorded by stimulating the posterior tibial nerve even in those subjects. Diabetic retinopathy and nephropathy also tended to rise with increasing latency of cortical P37. The latency of cortical P37 is an important parameter in assessing diabetic neuropathy.

Adult↗
PubMed1989

Metabolism of pyrazinamide and allopurinol in hereditary xanthine oxidase deficiency.

The metabolism of pyrazinamide and allopurinol was studied in three xanthinuric patients from two families with hereditary xanthinuria to determine whether both substrates were oxidized only by xanthine oxidase or by other oxidases as well. One xanthinuric patient could neither metabolize pyrazinamide into 5-hydroxypyrazinamide nor allopurinol into oxypurinol. Two xanthinuric patients could metabolize both pyrazinamide into 5-hydroxypyrazinamide and allopurinol into oxypurinol but could not oxidize pyrazinoic acid to 5-hydroxypyrazinoic acid. These findings suggest that xanthinuria comprises at least two subgroups.

Adult↗
PubMed1989

Aspartic acid at position 57 of DQ beta chain does not protect against type 1 (insulin-dependent) diabetes mellitus in Japanese subjects.

HLA DQ beta chain, in particular amino acid at position 57, has been reported to contribute to susceptibility and resistance to Type 1 (insulin-dependent) diabetes mellitus in Caucasians. Resistance has been proposed to be conferred by aspartic acid at this position. To ascertain the association of HLA DQ beta and DR beta genes with Type 1 diabetes in Japanese subjects, ten Japanese Type 1 diabetic patients were investigated at DNA level. Genomic DNA was amplified by polymerase chain reaction, and dot blot analysis was carried out using the amplified DNA with allele specific oligonucleotide probes. All patients had aspartic acid at position 57 of at least one of their two DQ beta chains, and there was no significant difference of amino acids at the same position of DR beta chain in patients compared to control subjects. These data indicate that the protective role of aspartic acid at position 57 of DQ beta chain is less significant in Japanese compared with Caucasian subjects.

Aspartic Acid↗
PubMed1989

Effect of glucagon-(1-21)-peptide on secretin-stimulated pancreatic exocrine secretion in anesthetized dogs.

The effects of glucagon-(1-21)-peptide on pancreatic exocrine secretion and plasma glucose levels were studied and compared with those of native glucagon in anesthetized dogs. Intravenous bolus administration of 1 nmol or 10 nmol/kg of glucagon-(1-21)-peptide evoked a significant inhibition of secretin-stimulated pancreatic juice secretion and protein output in a dose-dependent manner, as equimolar doses of glucagon did. Native glucagon induced an immediate and transient increase in pancreatic juice volume, which was followed by a significant inhibition. However, glucagon-(1-21)-peptide showed only the inhibitory action. Glucagon-(1-21)-peptide had no effect on plasma glucose levels even when a dose of 10 nmol/kg was given. The results suggest that the N-terminal amino-acid residues of glucagon play an important role in the inhibition of pancreatic exocrine secretion.

Animals↗
PubMed1989

Autoantibodies to the insulin receptor impair clearance of plasma endogenous insulin.

Plasma insulin clearance was studied in a patient with autoantibodies to the insulin receptor, manifesting persistent hyperinsulinemia associated with alternating hyper- and hypoglycemia. In the postabsorptive period, the plasma glucose level gradually decreased. To prevent the development of hypoglycemia, glucose was infused and the glycemic level was clamped at 50 mg/dl without insulin infusion. The plasma C-peptide level was below the detectable range during the clamp, indicating no appreciable secretion of insulin. The plasma insulin level declined exponentially with a markedly prolonged disappearance rate (half-time: 3.0 h) during the study. These results indicate that hyperinsulinemia in the postabsorptive period in this patient is attributable to the impairment of plasma insulin clearance through receptor-mediated mechanisms, and also confirm that the receptor plays the principal role in plasma insulin removal.

Acanthosis Nigricans↗
PubMed1989

Duct-islet cell tumor of the pancreas. A case report with immunohistochemical and electron microscopic findings.

A case of pancreatic tumor with features of both duct and islet cell components was found incidentally at autopsy in a 76-year-old male who had died of intrahepatic cholangiocarcinoma. The tumor, measuring about 1.0 cm in diameter, was located in the pancreatic tail. The tumor was composed of two distinct cell populations, islet cells and duct cells. Immunocytochemically, nearly all of the former cells were positive for insulin but negative for cytokeratin, carcinoembryonic antigen (CEA) and mucin, while the latter were positive for cytokeratin, CEA and mucin but negative for insulin. Additionally, a majority of the tumor cells that had formed islet-like structures were positive for neuron-specific enolase (NSE), whereas NSE-positive cells were found only rarely in duct components. Electron microscopy confirmed the presence of two cell populations. Simultaneous occurrence of duct and islet cell components in a single pancreatic tumor indicates an intimate histogenetic relationship between pancreatic endocrine and duct cells.

Adenoma, Islet Cell↗
PubMed1989

Epithelioid hemangioendothelioma of the liver in primary biliary cirrhosis. A case report.

We report a case of primary epithelioid hemangioendothelioma of the liver occurring in a patient with primary biliary cirrhosis, stage III. The hepatic tumor was found incidentally by imaging techniques and was surgically resected under a tentative diagnosis of metastatic carcinoma. The resected tumor (1.8 x 1.6 cm) showed typical histologic features of epithelioid hemangioendothelioma. The tumor cells were positive for factor VIII-related antigen and were stained with Ulex europaeus lectin I. Ultrastructurally, the tumor cells showed cytoplasmic vacuoles, tight junctions, basal lamina, pinocytotic vesicles, bundles of thin filaments (approximately 10 nm in diameter) and Weibel-Palade bodies. The non-tumorous part of the liver showed features of primary biliary cirrhosis, stage III. This is the first reported case of epithelioid hemangioendothelioma occurring in a liver with primary biliary cirrhosis.

Aged↗
PubMed1989

Histological changes of the liver in experimental graft-versus-host disease across minor histocompatibility barriers. IV. A study of lymphocyte-endothelial interaction.

It has been reported in human hepatic graft-versus-host disease (GVHD) that an attachment of lymphocytes to vascular wall, the feature called "endothelialitis", is the most important predictive histologic sign of GVHD. However, its precise nature and significance in GVHD are still unknown. We developed experimental mouse GVHD across minor histocompatibility barriers and examined the lesion during a 14-month period after transplantation. The lesion was transiently found, appearing first at 4 days after transplantation, reaching a maximal level at 2 weeks and disappearing 5 weeks after transplantation. Electron microscopically, an intimate interaction between lymphocyte and endothelial cell was demonstrated. Lymphocytes showed irregular cytoplasmic processes and pseudopods and were in close contact with endothelial cells. Lymphocytes frequently penetrated in between and under the endothelial cells, and migrated into the perivascular spaces. Immunohistochemical analysis revealed that the vast majority of lymphocytes attached to the endothelial cells are helper/inducer T cells, indicating the cardinal role of helper/inducer T cell in lymphocyte-endothelial cell interactions. These results, together with previous evidence of the presence of Ia antigens and an antigen-presenting ability of vascular endothelial cells, suggest that the attachment of lymphocytes to the vascular endothelial cells in the early course of GVHD may represent an in situ morphologic representation of antigen presentation by endothelial cells to helper T cells.

Animals↗
PubMed1989

Hyperinsulinemia due to impaired insulin clearance associated with fasting hypoglycemia and postprandial hyperglycemia: an analysis of a patient with antiinsulin receptor antibodies.

Antiinsulin receptor antibodies were detected in the serum of a patient with insulin-resistant diabetes. Fasting hypoglycemia and postprandial hyperglycemia recurred every day. The plasma insulin level was 553 +/- 359 pmol/L [77 +/- 50 microU/mL (mean +/- SD)] in the fasting state and rose above 7500 pmol/L postprandially. The glycemic clamp at 2.8 mmol/L (50 mg/dL) without insulin infusion revealed that the half-life of plasma endogenous insulin was 173 min, indicating severely impaired plasma insulin clearance. During the clamp the glucose infusion rate was almost constant (0.9-1.2 mg/kg.min) despite an exponential decline in the plasma insulin level from 460 pmol/L (65 microU/mL) to 129 pmol/L (18 microU/mL). Intravenous insulin administration did not appreciably accelerate the basal constant decrease in the plasma glucose level during the postabsorptive period. These results indicate the coexistence of marked insulin resistance and constant ability to decrease plasma glucose level. In in vitro experiments, antireceptor immunoglobulin G from this patient increased the fructose 2,6-bisphosphate concentration in the presence of glucagon (less than 0.1 nmol/L) in primary cultured rat hepatocytes. The antireceptor immunoglobulin G stimulated autophosphorylation of rat liver insulin receptor. We conclude that antiinsulin receptor antibodies could impair plasma insulin clearance, resulting in persistent hyperinsulinemia, and that continuous receptor stimulation by the antibodies was responsible for the development of hypoglycemia.

Animals↗