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Biomedical subjects

H Taniguchi

Publications and source records attributed to H Taniguchi.

At least 415 records · Page 23Linked to original sources
PubMed1992

Inhibition of azoxymethane-induced experimental colon carcinogenesis in Wistar rats by 6-hydroxydopamine.

The effects of 6-hydroxydopamine (6-OHDA) on the incidence, number and histology of colon tumors induced by azoxymethane (AOM), and on norepinephrine (NE) concentration in the colon wall and the labelling index of the colon mucosa were investigated in Wistar rats. Rats received sub-cutaneous (s.c.) injections of AOM once a week for 10 weeks, and throughout 35 weeks were also given intraperitoneal (i.p.) injections of 6-OHDA. Prolonged administration of 6-OHDA was found to cause a significant reduction in the incidence and number of colon tumors. However, it had no influence on the histological features or depths of involvement of colon tumors and/or adenocarcinomas. Its administration also caused significant decreases in the NE concentration in the colon wall and in the labelling index of the colon mucosa. Our findings indicate that 6-OHDA has a protective effect against colon carcinogenesis, and that the activity of the sympathetic nervous system may have an important influence on colon carcinogenesis.

Adenocarcinoma↗
PubMed1992

Attenuating effect of ornithine decarboxylase inhibitor (1,3-diaminopropane) on bombesin enhancement of gastric carcinogenesis induced by N-methyl-N'-nitro-N-nitrosoguanidine.

The effects of combined administration of bombesin and the ornithine decarboxylase (ODC) inhibitor 1,3-diaminopropane (DAP) on the incidence and number of gastric tumors induced by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), the ODC activity of the gastric wall and the labelling index of the gastric mucosa were investigated in inbred Wistar rats. Rats were given drinking water containing MNNG (50 micrograms/ml) for 25 weeks and then drinking water containing DAP (2.5 g/l) and/or injections of 40 micrograms/kg body weight of bombesin in depot form every other day. Administration of bombesin alone resulted in significant increases in the incidence of gastric cancers, the ODC activity of the antral portion of the gastric wall and the labelling index of the antral mucosa. Administration of DAP with bombesin significantly reduced enhancement by the latter of gastric carcinogenesis, ODC activity of the antral portion of the gastric wall and the labelling index of the antral mucosa. Our results suggest that ODC inhibition attenuated the enhancement of gastric carcinogenesis by bombesin, and that this enhancement by bombesin was mediated by polyamine biosynthesis.

Adenocarcinoma↗
PubMed1992

Enhanced induction of colon carcinogenesis by azoxymethane in Wistar rats fed a low-protein diet.

The effects of ad libitum feeding of synthetic, low-protein diets on the incidence, number and histology of colon tumors induced by azoxymethane (AOM), on the norepinephrine concentration in the colon wall tissue and on the labelling index of colon mucosa were investigated in Wistar rats. Rats received 10 weekly injections of 7.4 mg/kg body weight of AOM and were given synthetic diets of equal calorie content containing 25% casein (normal-protein diet), 10% casein (low-protein diet) or 5% casein (very-low-protein diet). Administration of the low- and very-low-protein diets resulted in significant increases in the incidence and number of colon tumors at week 30. However, it did not affect the histology of the colon tumors. The low- and very-low-protein diets also resulted in significant increases in norepinephrine concentration in the proximal and distal portions of the colon wall and in the labelling indices of both parts of the colon mucosa. Our findings indicate that low- and very-low-protein diets enhance colon carcinogenesis and that this may be related to their effects in increasing the norepinephrine level in the colon wall and in stimulating proliferation of colon epithelial cells.

Adenocarcinoma↗
PubMed1992

Vascular inflow exclusion and hepatic resection.

Seventy-nine patients undergoing hepatic resection without manipulation of the vena cava were divided into three groups. Group 1 consisted of 32 patients in whom hepatic hilar vascular exclusion was not performed. Group 2 (20 patients) had vascular inflow exclusion performed at the operative site only (right or left unilateral exclusion). Group 3 (27 patients) had total inflow exclusion during hepatic resection. There were no significant differences between the groups in blood loss or blood transfusion requirement. On the third day after operation, the serum glutamic-pyruvic transaminase level in group 3 was significantly higher than that in group 1 (P less than 0.01). Vascular inflow exclusion may not be essential for successful hepatic resection.

Adult↗
PubMed1992

Clinical significance of serum colloid osmotic pressure in relation to pulmonary edema and coronary instability in patients with unstable angina.

Several investigators demonstrated that severe reduction of colloid osmotic pressure (COP) predicts a fatal outcome in patients with cardiopulmonary failure. To evaluate the clinical significance of COP in relation to pulmonary edema, we studied 117 patients with unstable angina admitted in the hospital within 24 h after the chest pain. The mean COP of all 117 patients was 24.8 +/- 3.7 mmHg. COP was significantly lower in patients with pulmonary edema, according to the chest x-ray findings, compared with the patients without it. Among 26 patients with emergency coronary arteriography, a fairly good correlation was observed between coronary jeopardy score and COP (r = -0.57, p less than 0.005). Furthermore, COP in patients who survived 26 months after the hospital discharge was significantly higher than that of the nonsurvivors. Thus, measurement of COP is advised for monitoring patients with unstable angina.

Angina, Unstable↗
PubMed1992

Acute myelomonocytic leukemia with marrow eosinophilia showing 5q- and 16q22 mosaicism.

We report an 82-year-old Japanese female with acute myelomonocytic leukemia with dysplastic marrow eosinophilia (FAB M4Eo) exhibiting a partial deletion of the long arm of chromosome 5, del(5)(q13q31) and a derivative chromosome 16 with a breakpoint at band 16q22, in addition to 5q-. The patient had a history of a preleukemic phase for several months with marked dysplasia in trilineage marrow cells, in addition to leukemic features compatible with M4Eo. These findings strongly suggested that the leukemic cells in this case were derived from a preleukemic clone with a del(5q).

Aged↗
PubMed1992

Enhancement of dopaminergic agonist bromocriptine of gastric carcinogenesis induced by N-methyl-N'-nitro-N-nitrosoguanidine in Wistar rats.

The effects of the dopamine agonist 2-bromo-alpha-ergocryptine methanesulfonate (bromocriptine) on the incidence, number and histology of gastric cancer induced by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) were investigated in Wistar rats. Rats were given 1 or 2 mg kg-1 body weight of bromocriptine subcutaneously every other day in depot form after 25 weeks of oral treatment with MNNG. Prolonged administration of bromocriptine at both dosages every other day resulted in a significant increase in the incidence and number of gastric cancers of the glandular stomach by week 52. Bromocriptine treatment did not influence the histological type of gastric cancer, but caused a significant increase in the labelling index of epithelial cells of the antrum. These findings indicate that the dopamine agonist bromocriptine promotes gastric carcinogenesis, and that this effect may be related to its effect in increasing proliferation of epithelial cells in the antral mucosa.

Adenocarcinoma↗
PubMed1992

Synthetic reaction of Cellvibrio gilvus cellobiose phosphorylase.

The synthetic reactions of the cellobiose phosphorylase from Cellvibrio gilvus were investigated in detail. It was found that, besides D-glucose, some sugars having substitution or deletion of the hydroxyl group at C2 or C6 of the D-glucose molecule could serve as a glucosyl acceptor, though less effectively than D-glucose. The enzyme showed higher activity with beta-D-glucose than with the alpha-anomer as an acceptor. This result indicates that it recognizes the anomeric hydroxyl group not involved directly in the reaction. beta-D-Cellobiose was also phosphorolyzed faster than the alpha-anomer. Substrate inhibition was observed with D-glucose, 6-deoxy-D-glucose, or D-glucosamine as an acceptor, with D-glucose being most inhibiting. This inhibition was studied in detail and it was found that D-glucose competes with alpha-D-glucose-1-phosphate for its binding site. A model of competitive substrate inhibition was proposed, and the experimental data fit well to the theoretical values that were calculated in accordance with this model.

Binding, Competitive↗
PubMed1992

Platelet-activating factor in bronchoalveolar lavage fluid of patients with adult respiratory distress syndrome.

1. To clarify the role of platelet-activating factor (PAF) in the development of adult respiratory distress syndrome (ARDS), we performed bronchoalveolar lavage (BAL) in 19 patients with ARDS and examined cell populations, albumin concentrations and PAF levels. PAF levels were measured by a newly developed radioimmunoassay. 2. In the BAL fluid of ARDS patients, neutrophil percentages and albumin concentrations markedly increased compared with control subjects. 3. PAF was detected in 14 of 19 patients with ARDS, whereas it did not exist in the control subjects. 4. Furthermore, we investigated the priming effect of recombinant human tumour necrosis factor-alpha (TNF alpha), which is known to be one of the most important mediators in the development of ARDS, on PAF production induced by the calcium ionophore in neutrophils. 5. Pre-incubation with TNF alpha dose-dependently increased both extracellular and intracellular PAF production in neutrophils. 6. These results suggest that PAF might play an important role in the development of ARDS.

Adolescent↗
PubMed1992

Effect of gamma-butyrolactone on baclofen inhibition of gastric carcinogenesis induced by N-methyl-N'-nitro-N-nitrosoguanidine in Wistar rats.

The effect of gamma-butyrolactone (GBL) on inhibition by baclofen of gastric carcinogenesis was investigated in Wistar rats. In week 52, baclofen significantly decreased the incidence of gastric cancers. Concomitant treatment with GBL significantly increased gastric acid secretion but had no influence on the inhibition by baclofen of gastric carcinogenesis. This finding suggest that GBL significantly increased the sensitivity of gamma-aminobutyric acid (GABA) receptor to GABA mimetics in gastric acid secretion but not in the inhibitory effect of gastric carcinogenesis.

4-Butyrolactone↗
PubMed1992

Attenuation by the GABA receptor agonist baclofen of experimental carcinogenesis in rat colon by azoxymethane.

The effects of the gamma-amino-n-butyric acid (GABA)A receptor agonist muscimol, and the GABAB receptor agonist baclofen, on colon carcinogenesis induced by azoxymethane in Wistar rats were tested. Administration of either muscimol or baclofen had no influence on the incidence of colon tumors at week 30. However, almost all the colon tumors that developed in rats treated with baclofen were adenomas, whereas in the control group the tumors were mainly adenocarcinomas. In contrast, administration of muscimol did not affect the histological types of the colon tumors. These findings indicate that baclofen inhibits the growth of colon tumors via the GABAB receptor.

Adenocarcinoma↗
PubMed1992

Enhancement by methionine- and leucine-enkephalin of gastric carcinogenesis induced by N-methyl-N'-nitro-N-nitrosoguanidine in Wistar rats.

The effects of the opioid receptor agonists methionine-enkephalin (Met-ENK) and leucine-enkephalin (Leu-ENK) on gastric carcinogenesis induced by N-methyl-N'-nitro-N-nitrosoguanidine were investigated in Wistar rats. After 25 weeks of oral treatment with the carcinogen, the rats received subcutaneous injections of Met-ENK (20 micrograms/kg) or Leu-ENK (20 micrograms/kg) once every 2 days. The prolonged administrations of Met-ENK and Leu-ENK significantly increased the incidence of gastric cancers in week 52. Treatments with these opioid receptor agonists significantly increased the labeling index of the antral mucosa. These findings indicate that opioids enhance gastric carcinogenesis and suggest that their effects may be related to their influence on increasing proliferation of the antral epithelial cells.

Animals↗
PubMed1992

7S collagen in bronchoalveolar lavage fluid of patients with adult respiratory distress syndrome.

To evaluate the disruption of the basement membrane in the pathogenesis of adult respiratory distress syndrome (ARDS), we measured the level of 7S collagen in the bronchoalveolar lavage (BAL) fluid of patients with ARDS and normal control subjects by using a radioimmunoassay method. Twelve of 14 patients with ARDS had evidence of 7S collagen in the BAL fluid, but no 7S collagen was detected in the BAL fluid of the controls. The mean 7S collagen concentration of the BAL fluid in patients with ARDS was 19.6 +/- 9.4 ng/ml. In patients with ARDS, the BAL levels of 7S collagen correlated strongly with neutrophil counts (r = 0.813; p less than 0.01) and with elastase-complex (r = 0.914; p less than 0.01). We conclude that 7S collagen may be an index of leukocyte-mediated lung injury in patients with ARDS, and detection of 7S collagen in BAL fluid is useful for evaluating the disruption of basement membrane.

Adult↗
PubMed1992

Role of platelet-activating factor in pulmonary edema after coronary ligation in dogs.

To evaluate whether PAF is related to the precipitation of pulmonary edema after myocardial ischemia, we studied the effect of a specific PAF antagonist, CV-6209, on the extravascular lung water level measured by the thermal-dye double indicator dilution method, ETV, after coronary ligation in dogs. Eight dogs served as sham control animals (group 1). The proximal left anterior descending coronary artery was ligated for 45 min in eight dogs (group 2), and the coronary artery was ligated after pretreatment with CV-6209 (1 mg/kg) in eight dogs (group 3). The ETV increased significantly after coronary ligation in groups 2 and 3. The amount of increase in ETV in group 2 was significantly larger than in group 3. Thus, CV-6209 can prevent the accumulation of extravascular lung water after coronary ligation without producing changes in pulmonary vascular dynamics, indicating that PAF may play an important role in pulmonary edema after myocardial ischemia.

Animals↗
PubMed1992

[Reproductive and developmental toxicity study of prednisolone farnesylate (PNF)--study by subcutaneous administration of PNF prior to and in the early stages of pregnancy in rats].

A fertility study of Prednisolone farnesylate (PNF), a newly synthesized corticosteroid, was conducted in Sprague-Dawley rats. This compound was administered subcutaneously at dose levels of 0(control), 0.04, 0.2 and 1 mg/kg/day to males for 63 days before mating and during the mating period, and to females for 14 days before mating, through the mating period and until day 7 of pregnancy. Each 24 male and female rats were mated, and females were killed on day 20 of pregnancy to examine their fetuses. 1. In the parental animals, loss of fur or thin fur and incrustation of treated site occurred in male rats treated at doses of 0.2 mg/kg or more and female rats treated at dose of 1 mg/kg, and at the same dose groups, the thinning of skin, atrophy of the thymus and intention of the substance at the injected site were noted. Moreover, body weight gains and food consumption were suppressed in both sexes treated at the dose of 1 mg/kg. 2. Fertility and reproductive ability in both sexes, and estrus cycles in female rats were not affected by administration of PNF. 3. In the fetuses, no embryonic or fetal lethal effect and teratogenic effect were noted. From these results, the no-effect dose levels of PNF on the parental general states, the parental reproductive ability and those of the fetuses are thought to be 0.04 mg/kg/day, 1 mg/kg/day or more and 1 mg/kg/day or more, respectively, under the experimental conditions of this study.

Animals↗
PubMed1992

[Reproductive and developmental toxicity study of prednisolone farnesylate (PNF)--study by subcutaneous administration of PNF during the period of fetal organogenesis in rats].

A teratogenicity study of Prednisolone farnesylate (PNF), a newly synthesized corticosteroid, was conducted in Sprague-Dawley rats. This compound was administrated subcutaneously to female rats at dose levels of 0(control), 1, 5 and 25 mg/kg/day, once a day, for 11 days from day 7 to day 17 of pregnancy. In each dose group, 26 or 27 dams were killed on day 20 of pregnancy to examine their fetuses. The remaining 14 or 15 dams of each group were allowed to litter naturally, and observations were made on the postnatal growth and development of their offspring. 1. In the dams treated at doses of 1 mg/kg or more, decreased body weight gains and food consumption and retention of the substance at the injected site were noted. However, general signs, parturition, lactation and nursing behaviors were not affected by the administration of PNF. 2. In the F1 fetuses, no embryonic or fetal lethal effect, fetal retardation and teratogenic effect were noted. 3. In the F1 newborns, the postnatal growth, development, responses, behaviors, learning ability and reproductive ability were not influenced. Additionally, no embryonic or fetal abnormalities of their fetuses (F2) were detected. From these results, the no-effect dose levels of PNF on the parental general states, the parental reproductive ability and those of the F1 offspring are thought to be less than 1 mg/kg/day, 25 mg/kg/day and 25 mg/kg/day, respectively, under the experimental conditions of this study. Moreover, the F2 fetuses are not affected by doses up to 25 mg/kg/day of PNF.

Animals↗
PubMed1992

[Reproductive and developmental toxicity study of prednisolone farnesylate (PNF)--study of subcutaneous administration of PNF during the perinatal and lactation periods in rats].

The effects of Prednisolone farnesylate (PNF), a newly synthesized corticosteroid, administrated during the perinatal and postnatal periods were studied in Sprague-Dawley rats. This compound was injected subcutaneously to female rats at dose levels of 0(control), 0.05, 0.5 and 5 mg/kg/day, once a day, for the period from day 17 of pregnancy to day 21 after parturition. Twenty-two to 25 dams in each dose group were allowed to litter naturally, and observations were made on the postnatal growth and development of their offspring. 1. In the dams treated at doses of 0.5 and 5 mg/kg, decreased body weight gains, atrophy of the thymus and retention of the substance at the injected site were noted. However, general signs, food consumption, parturition, lactation and nursing behaviors were not affected by the administration of PNF. 2. In the F1 newborns, the postnatal growth, development, responses, behaviors, learning ability and reproductive ability were not influenced. Additionally, no embryonic or fetal abnormalities of their fetuses (F2) were detected. From these results, the no-effect dose levels of PNF on the parental general states, the parental reproductive ability and those of the F1 offspring are thought to be 0.05 mg/kg/day, 5 mg/kg/day or more and 5 mg/kg/day or more, respectively, under the experimental conditions of this study. Moreover, the F2 fetuses are not affected by doses up to 5 mg/kg/day of PNF.

Animals↗