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N Shimojo

Publications and source records attributed to N Shimojo.

At least 145 records · Page 8Linked to original sources
PubMed1987

Changes in serum enzyme activity after transcatheter arterial embolization for hepatic neoplasm.

We assayed serum levels of certain enzymes and tumor markers in patients after transcatheter arterial embolization (TAE) to evaluate the effectiveness of this treatment. Twenty patients had hepatocellular carcinoma and two patients had metastases to the liver from colon cancer. Assays were first done immediately after TAE and were continued for the next 12 days. Glutamic oxaloacetic transaminase (GOT; EC 2.6.1.1, L-aspartate:2-oxoglutarate aminotransferase), glutamic pyruvic transaminase (GPT; EC 2.6.1.2, L-alanine:2-oxoglutarate aminotransferase), and lactate dehydrogenase (EC 1.1.1.27; (S)-lactate:NAD+ oxidoreductase) peaked 24 to 48 h after TAE and returned to the base lines in 7 to 10 days. Mitochondrial GOT (mGOT) and glutamate dehydrogenase (GLDH; EC 1.4.1.2, L-glutamate:NAD+ oxidoreductase) also peaked at the same time after TAE. alpha-Fetoprotein peaked 2 h after TAE and decreased to half of the baseline on day 7. Carcinoembryonic antigen peaked at 24 h and fell at 48 h only in the patients with colon cancer. The total amount of cytosolic GOT, GPT, mGOT, and GLDH released was correlated to the volume of the necrotic mass estimated by computed tomography scans. The correlation coefficients for mGOT and GLDH were r = 0.919 and r = 0.939 (both p less than 0.001), respectively. Assays of mGOT and GLDH may be useful to estimate the volume of the necrotic mass of a hepatoma or metastatic carcinoma in the liver.

Carcinoma, Hepatocellular↗
PubMed1987

Comparison of N-acetyl-beta-D-glucosaminidase and alanine aminopeptidase activities for evaluation of microangiopathy in diabetes mellitus.

The activities of urinary N-acetyl-beta-D-glucosaminidase (NAG) and alanine aminopeptidase (AAP) were measured in 207 diabetic patients and 57 healthy controls, and the relationship of these enzymes to different stages of diabetic microangiopathy was studied. Diabetics with clinical proteinuria had higher urinary NAG and AAP (17.7 +/- 1.9 and 42.8 +/- 4.9 U/g creatinine, mean +/- SE, respectively) than healthy controls (1.8 +/- 0.1 and 10.0 +/- 0.4) or diabetics without proteinuria. Among diabetics without proteinuria, NAG excretion in those with retinopathy was slightly higher than in those without (6.4 +/- 0.5 v 5.4 +/- 0.4), and AAP in those with retinopathy was significantly higher than in those without (23.0 +/- 1.5 v 17.4 +/- 0.8, P less than 0.01). Urinary albumin measured by radioimmunoassay and lysozyme in diabetics with retinopathy but without proteinuria was higher than those without retinopathy (P less than 0.001 and P less than 0.01). The increase in albumin was the greatest in diabetics with long duration of the disease (greater than or equal to 8 years); however, NAG and AAP increased more significantly in those with high hemoglobin A1c than in patients with long duration.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetylglucosaminidase↗
PubMed1987

Biochemical effects on combined gases of nitrogen dioxide and ozone. I. Species differences of lipid peroxides and phospholipids in lungs.

In the present study, changes of lipid peroxides, phospholipids and antioxidant levels in lungs of 4 animal species exposed to the combined gases of NO2 and O3 were compared. Male mice, hamsters, rats and guinea pigs were used. Lipid peroxides were increased significantly in the lungs of mice and guinea pigs exposed to the combined gases, but not in hamsters and rats. Changes of alpha-tocopherol (VE) contents were slight. On the other hand, non-protein sulfhydryl (NPSH) contents were increased strikingly, especially in hamsters, but were not increased in guinea pigs. Phosphatidylcholine (PC) contents were increased and phosphatidylethanolamine (PE) contents were decreased by the exposure to the combined gases, with the order guinea pig greater than mouse greater than rat. In hamsters no changes were seen. The changes of fatty acid composition in guinea pigs and mice were marked, the increases of palmitate and palmitolate and the decreases of polyunsaturated fatty acid were especially characteristic. These changes in phospholipid class and fatty acid composition may be a "a kind of adaptation phenomenon" to avoid further lipid peroxidation. On the other hand, the changes in hamsters and rats were small. The results show the existence of species differences in lipid peroxide formation by exposure to the combined gases of NO2 and O3. They were found to be related to the contents of antioxidants and the compositions of phospholipids and their fatty acids.

Animals↗
PubMed1987

Tissue kallikrein and bradykinin do not have direct insulin-like actions on skeletal muscle glucose utilization.

Studies suggest that the actions of insulin on glucose metabolism may be mediated through activation of a membrane-bound serine protease with properties similar to a kallikrein-like enzyme. Also, bradykinin, a vasoactive product of kallikrein's action upon kininogen substrates, increases glucose uptake when infused into the human forearm. To determine whether a kallikrein or a kinin directly affects cellular glucose metabolism or participates in mediating insulin's actions, we studied their effects on isolated rat soleus muscle. Although trypsin (1.34 microM) increased incorporation of glucose into muscle glycogen to the same extent as insulin (200 mu units/ml), a purified rat tissue (urinary) kallikrein (0.4-1.34 microM) produced no such effect. Furthermore, the tissue kallikrein inhibitor, aprotinin, or a polyclonal kallikrein antiserum did not inhibit the action of insulin on incorporation of glucose into muscle glycogen. Treatment of the muscle preparation with bradykinin (1nM - 10 microM) did not result in any change in basal or insulin-stimulated (20 - 2000 mu units/ml) entry of glucose into glycogen or the glycolytic pathway. Bradykinin (1nM - 10 microM) also did not influence basal or insulin-stimulated (1000 mu units/ml) initial rates of glucose transport. These studies suggest that the previously observed in vivo effects of bradykinin on peripheral glucose uptake are probably mediated by changes in tissue perfusion rather than direct kinin effects on skeletal muscle, and that the putative membrane serine protease involved in the insulin-effector system is not tissue kallikrein.

Animals↗
PubMed1986

Mercaptalbumin as a selective cadmium-binding protein in rat serum.

Cadmium-binding proteins in blood serum were determined on a gel permeation column by high-performance liquid chromatography-inductively coupled argon plasma-atomic emission spectrometry. Cadmium chloride was administered iv to female rats of the Wistar strain in a single dose of 0.4 mg Cd/kg body wt and the rats were killed 1, 2, 3, 5, 10, 20, and 30 min after the injection. The blood serum was separated on an Asahipak GS-520 column and cadmium concentration in the eluate was monitored continuously along with sulfur, zinc, copper, iron, and phosphorus concentrations. Cadmium was selectively bound to mercaptalbumin and the metal was eliminated from blood serum within 30 min in a biphasic mode. Addition in vitro of cadmium chloride into fresh blood serum revealed that cadmium is bound selectively to mercaptalbumin up to approximately 14 micrograms Cd/ml serum. Excess cadmium in blood serum was found in the lower molecular weight fraction. Nonmercaptalbumin produced by oxidative disulfide bond formation between albumin and glutathione or cysteine was not able to bind cadmium. Sulfur and other element profiles were helpful in characterizing metal-binding proteins.

Animals↗
PubMed1986

Antigenic determinants on thyroglobulin recognized by T cells in patients with chronic thyroiditis.

It was found that the proliferating cells to thyroglobulin (Tg) in patients with chronic thyroiditis are confined to a T cell subpopulation. Then, we attempted to characterize the antigenic determinants of Tg recognized by T cells from patients with chronic thyroiditis by Tg-induced DNA-synthetic response. T cells from patients could respond to Tgs from whales, pigs and chickens as well as to human Tg. These findings indicated that epitopes on Tg recognized by T cells were shared by Tgs from various species. In addition, the T cells from different individuals varied in specificity.

Adolescent↗
PubMed1986

Autoantibodies to thyroid peroxidase in patients with chronic thyroiditis: effect of antibody binding on enzyme activities.

Using thyroid peroxidase (TPO), which was purified from the thyroid of patients with Graves' disease, we attempted to determine whether sera from patients with chronic thyroiditis contained antibodies to the enzyme. When the binding was tested by ELISA, sera from patients with chronic thyroiditis revealed high binding activities to TPO. When TPO was incubated with IgG from sera followed by treatment with protein A-Sepharose and centrifugation, the remaining TPO activities in the supernatant fraction were lower in most of the patients, as compared to normal controls. Moreover, IgG purified by DEAE-cellulose chromatography from sera in patients interfered with the TPO activities. Titres of anti-TPO antibodies correlated well with those of anti-microsome antibodies. These results indicate the presence of autoantibodies to TPO in sera of most patients with chronic thyroiditis and that TPO may be one component of microsome antigen complexes recognized by the autoantibodies. Studies on the inhibition of TPO by IgG isolated from sera of patients using guaiacol and iodide assays revealed that at least three epitopes of TPO molecule were recognized by autoantibodies and that the antigenic determinants on TPO molecule recognized by autoantibodies could be heterogeneous in patients.

Adolescent↗
PubMed1985

Depression of serum cholinesterase activity by cadmium.

Two serum enzymes which originate from the liver under different circumstances were examined as potential biological indicators in serum for cadmium toxicity. The first of those is an enzyme that leaks from damaged liver cells. The second is an enzyme that is secreted by the normal functioning liver. Cadmium chloride was injected s.c. into male and female rats of the Wistar strain (8, 15 and 22 weeks old), at doses of 1.0, 1.5 and 2.0 mg Cd/kg body weight (in total 18 groups). Cholinesterase (CHE; EC 3.1.1.8) activity in serum was found to decrease with time after the administration of a single injection of cadmium chloride and, in all experimental groups, was significantly lower than the control values on day 2 after the injection. Glutamic pyruvic transaminase (GPT; EC 2.6.1.2) activity in serum, however, increased only in the oldest group of males receiving the high dose levels of cadmium. A time-course experiment in which male and female rats 15 weeks of age were administered 1.5 mg Cd/kg body weight showed that the serum CHE activity started to decrease on day 1 after the injection, attained the lowest level on days 2 and 3, and then recovered almost to control levels on day 5. On the other hand, the GPT activity remained at or less than control values throughout the experimental period. The results indicate that CHE activity in serum is a sensitive biological indicator for cadmium toxicity.

Alanine Transaminase↗
PubMed1985

Induction and detection of a third isometallothionein (metallothionein-II') in rat liver.

A third isometallothionein was shown to be present during metallothionein synthesis, particularly following induction by zinc (Zn). It appeared to be closely related to metallothionein-II and the relative amount decreased with time, with only a minor peak after repeated cadmium (Cd) loading. On-line column switching by high-performance liquid chromatography (HPLC)-atomic absorption spectrophotometry (AAS) is effective in analysing and characterizing isometallothioneins.

Animals↗
PubMed1985

In vivo effects of nitrogen dioxide on the blood nitrate level and the Na+,K+-ATPase activity of red blood cells of rats.

Male Wistar rats were exposed to 0.4, 1.2 and 4.0 ppm NO2 for 13 weeks to examine the effects of NO2 on the blood nitrate concentration and the Na+,K+-ATPase activity of red blood cells. Exposures to 1.2 and 4.0 ppm NO2 caused an elevation of the blood nitrate level at the first, third and eighth week. The maximum concentration attained was 148% (P less than 0.001, at the third week) and 201% (P less than 0.001, at the eighth week) of the controls at 1.2 and 4.0 ppm NO2, respectively. On the other hand, the nitrate concentration was decreased to the control level at the second, fourth and thirteenth weeks. 0.4 ppm NO2 caused a progressive but slight increase in the blood nitrate concentration from the third week and reached the maximum (122% of the control, P less than 0.001) at the eighth week. The Na+,K+-ATPase activity decreased slightly from the first week upon exposure to 4.0 ppm NO2 and reached the minimum (72% of the control, P less than 0.05) at the third week. Subsequently, the activity was increased to 159% (P less than 0.001) of the control at the eighth week. Exposure to 0.4 and 1.2 ppm NO2 caused fundamentally similar but less significant alterations of the Na+,K+-ATPase activity.

Animals↗
PubMed1985

Renal kallikrein in human and experimental diabetes mellitus.

Urinary kallikrein excretion was studied in a group of insulin-dependent diabetic patients in relation to glycemic control, and both urinary and renal tissue levels of kallikrein were measured in untreated and insulin-treated streptozotocin-diabetic rats. While on a fixed normal sodium diet, diabetic patients in poor glycemic control (HbA1c greater than 11%) showed elevated urinary kallikrein, compared to patients with HbA1c less than 11% or normal subjects. Strict glycemic control lowered kallikrein excretion in diabetic patients. In contrast, severely hyperglycemic diabetic rats had reduced urinary and renal kallikrein levels, compared to nondiabetic control rats, and the reduction in urinary kallikrein preceded the development of systolic hypertension. Insulin treatment normalized urinary kallikrein in diabetic rats, but resulted in increased renal kallikrein levels compared to nondiabetic rats. The differences in kallikrein abnormalities observed in diabetic patients and a diabetic animal model may possibly be related to renal hemodynamic changes in clinical and experimental diabetic states.

Adult↗
PubMed1984

Effects of nitrate and nitrite, chemical intermediates of inhaled nitrogen dioxide, on membrane components of red blood cells of rats.

Rat blood was incubated at 37 degrees C for 60 min with either NaNO3 or NaNO2 to examine the relationship between the decrease in the hexose content and Ca2+,Mg2+-ATPase activity of red cell membranes, and NO3- and NO2-. The hexose content decreased depending on the NaNO2 concentration up to 100 microM reaching 76% (p less than 0.05) of the control value. NaNO3 had little effect on the hexose content. On the other hand, the Ca2+,Mg2+-ATPase activity decreased depending on the NaNO3 concentration up to 200 microM, where the activity reached 75% (p less than 0.01) of the control value. The effect of NaNO2 on this activity was smaller than that of NaNO3. The sialic acid content and the Na+,K+-ATPase activity did not show significant alterations by incubation with NaNO2 and NaNO3 at below 100 microM. To examine the in vivo effects of NO2- and NO3-, 50 mM NaNO3 was intravenously injected into rats five times at hourly intervals (dose: 1.0 ml/kg body weight), and blood was collected 1 hr after the last injection. The activities of Ca2+,Mg2+- and Na+,K+-ATPases of red cell membranes were decreased to 68% (p less than 0.05) and 80% of the control value, respectively. Reduction by injection of 50 mM NaNO2 was smaller than that by 50 mM NaNO3. The results show that the hexose content and the Ca2+,Mg2+-ATPase activity of red cell membranes were decreased by NO-x that increased in the blood during short-term exposure of rats to NO2.

Animals↗
PubMed1983

Plasma inactive renin in patients with diabetes mellitus: effects of standing and the relation to serum protease inhibitor.

In order to investigate the mechanisms of increased plasma inactive renin in diabetics with microvascular complications, changes in active and inactive renin with the progress of diabetes mellitus were studied, and effects of standing on inactive renin release and the relationship between plasma inactive renin and serum trypsin or protease inhibitors wee also studied. Inactive renin increased with the aggravation of diabetes mellitus, but active renin didn't show significant changes with the aggravation of diabetes mellitus. Active renin was significantly increased both in the healthy subjects and in the diabetic patients when they were in an upright position, but no significant change was observed in inactive renin. Serum trypsin in diabetics with retinopathy and nephropathy was lower than that in those with no clinical sign of microangiopathy, but the correlation between plasma inactive renin and serum trypsin was not significant. There was a significant correlation between plasma inactive renin and serum alpha 2-globulin (r = 0.52, p less than 0.01). Although plasma inactive renin was not significantly correlated with serum alpha 1-antitrypsin, there was a significant correlation between plasma inactive renin and serum alpha 2-macroglobulin (r = 0.61, p less than 0.01). These results show that the increased levels of plasma inactive renin observed with the development of diabetic microangiopathy are probably related to the altered plasma protein metabolism observed in patients with diabetes mellitus. However, it is not clear whether this altered protein metabolism is related to the conversion from inactive to active renin.

Adult↗