PubMed Health⌕ Search

Biomedical subjects

Y Fukuta

Publications and source records attributed to Y Fukuta.

At least 55 records · Page 3Linked to original sources
PubMed1997

Correlation between intravenously supplied energy level and zinc metabolism in laparotomized rats.

We investigated the relationship between intravenous energy loading and zinc status in laparotomized rats. One of three test solutions consisting of 3% amino acid, the same amount of electrolytes (excluding zinc) and different concentrations of glucose were infused through the jugular vein for 5 d. The total energy was 109, 191 and 273 kcal/kg/d, respectively. Significantly positive correlations were observed between infusion energy and rat body weight changes (% of initial value) and between infusion energy and cumulative nitrogen balance. Regarding the zinc status, a negative correlation was found between infusion energy and plasma zinc concentration, and a positive correlation was observed between infusion energy and urinary zinc excretion. There was no significant relationship between infusion energy and hepatic zinc content. These results indicate that the zinc requirement might be increased when infusion energy is elevated and the nutritional status is improved. Zinc supplementation in the post-operative period should be considered in light of not only catabolism but also anabolism. Anabolism may be more important than catabolism in regard to zinc metabolism under relatively mild stress.

Animals↗
PubMed1996

Angiotensin II as a stimulator of Na(+)-dependent Ca2+ efflux from freshly isolated adult rat cardiomyocytes.

In cardiac tissues, angiotensin II causes inotropic and chronotropic effects on the heart. It is indicated that the mechanism of the inotropic effect of angiotensin II is attributed to an increase in cytosolic free calcium ([Ca2+]i) in cardiomyocytes. However, increased [Ca2+]i should be restored to a physiological level because cumulative elevation in [Ca2+]i leads to irreversible injury in cardiomyocytes. Whereas it is known that angiotensin II causes the increase in [Ca2+]i in cardiac cells, little is known about the mechanisms of decrease in [Ca2+]i in cardiomyocytes upon angiotensin II stimulation. In the present study, we examined the effect of angiotensin II on Ca2+ efflux from freshly isolated adult rat cardiomyocytes. Angiotensin II stimulated the efflux of 45Ca2+ from the cells in a concentration-dependent manner (10(-7)-10(-5) M). The 45Ca2+ efflux from the cells was inhibited by type 1 angiotensin II receptor inhibitor. The angiotensin II-stimulated 45Ca2+ efflux was not affected by deprivation of the extracellular Ca2+, but was dependent on the presence of extracellular Na+. These results indicate that angiotensin II stimulates extracellular Na(+)-dependent 45Ca2+ efflux from freshly isolated adult rat cardiomyocytes, probably through its stimulatory effect on the plasma membrane type 1 angiotensin II receptors which may couple to Na+/Ca2+ exchange.

Angiotensin II↗
PubMed1996

The effect of alpha-linolenic acid-rich emulsion on fatty acid metabolism and leukotriene generation of the colon in a rat model with inflammatory bowel disease.

The purpose of this study was to investigate the efficacy of alpha-linolenic acid-rich perilla oil emulsion (POE) in a rat model with trinitrobenzenesulfonic acid (TNB)-induced inflammatory bowel disease. Three different isocaloric solutions, which are glucose solution (FF), soybean oil emulsion (SOE) and POE, were infused for 14 days after instillation of TNB. After infusion, total cholesterol and phospholipid concentration in the plasma in the POE group were significantly decreased compared with the FF and SOE groups. Arachidonic acid level in the colonic phospholipids was significantly decreased and eicosapentaenoic acid level was significantly increased in the POE group compared with the FF and SOE groups. Thickness, damage score and leukotriene B4 content in the colon in the POE group were the lowest among the infusion groups. These results suggest that alpha-linolenic acid suppresses the synthesis of leukotriene B4 in the colon by changing the fatty acid composition in the colonic phospholipids and that POE may be effective in the improvement of inflammation in the colon.

Animals↗
PubMed1996

The nutritional effect of a-linolenic acid-rich emulsion with total parenteral nutrition in a rat model with inflammatory bowel disease.

The purpose of this study was to investigate the nutritional effect of perilla oil emulsion (POE) in a rat model with inflammatory bowel disease (IBD) induced by 2,4,6-trinitrobenzenesulfonic acid. POE and soybean oil emulsion (SOE) were infused at 20% of nonprotein energy during 7 days' total parenteral nutrition (TPN). After infusion of test solutions, body weight gain and cumulative nitrogen balance in the POE group were significantly higher than those in the fat-free TPN (FF) group after infusion of test solutions. Moreover, those in the POE group were higher than those in the SOE group, but no significant difference was observed between the POE and SOE groups. In the POE group, total cholesterol and phospholipid concentration in the plasma was significantly decreased compared with the FF and SOE groups. Triglyceride concentration in the plasma did not significantly differ between the POE, SOE and FF groups. Plasma lipid peroxide concentration in the POE group was significantly lower than that in the SOE group, but it was not different from the FF group. In fatty acid composition in the plasma total lipids, linoleic acid in the POE and SOE groups and alpha-linolenic acid in the POE group were significantly increased compared with those in the FF group. Arachidonic acid (AA) in the POE and FF groups were significantly decreased compared with that in the SOE group. Otherwise, eicosapentaenoic acid (EPA) in the POE group was significantly increased compared with that in the SOE and FF groups. EPA/AA ratio in the POE group was significantly increased compared with the SOE group. The thickness and damage score of the colon were significantly depressed in the POE group compared with the SOE group. These results suggest that POE has a superior nutritional effect and improves inflammation in the IBD.

Animal Nutritional Physiological Phenomena↗
PubMed1996

[Effect of amiloride on the early and late stage of postischemic recovery in isolated perfused rat hearts--possible involvement of Na+/H+ and Na+/Ca2+ exchange].

To investigate whether Na+/H+ exchange or Na+/Ca2+ exchange involves in the ischemic-reperfusion injury, we examined the effect of amiloride, a potent inhibitor of Na+/H+ exchange, on the ischemic reperfused rat heart. When, the hearts were loaded with 0.1 mM amiloride preischemically, the recovery of left ventricular developed pressure was significantly improved than that of the control group, whereas the recovery of heart rate was not influenced by amiloride pretreatment at 30 min of reperfusion. Measurement of intracellular cations revealed that intracellular Na+ accumulation in the early stage (within 5 min) of reperfusion was inhibited by amiloride pretreatment. On the other hand, in the late stage (from 5 min to 30 min) of reperfusion, Ca2+ overload was inhibited by amiloride. These results suggest that Na+/H+ exchange mainly participates in the early stage of reperfusion injury and Na+/Ca2+ exchange system, secondary to the Na+/H+ exchange, participates in the late stage of the reperfusion injury. Moreover, pretreatment with amiloride also decreased creatine phosphokinase activity in the coronary effluent and completely abolished the incidence of ventricular arrhythmia during reperfusion. It is assumed that the improvement of postischemic cardiac dysfunction induced by amiloride pretreatment may be attributable to its inhibition on the resultant Ca2+ accumulation during ischemia.

Amiloride↗
PubMed1996

Stereo-selective calcium antagonistic and binding properties of the enantiomers of lemildipine in vascular tissue of pigs and dogs.

Stereo-selective calcium antagonistic properties of the enantiomers of lemildipine (CAS 94739-29-4, NB-818) were assessed in vascular tissues, including pig coronary artery and dog cerebral artery. Ca2+ antagonistic action of (-)-lemildipine was about 5 times and 100 times more potent than nifedipine and (+)-lemildipine, respectively. (-), (+), and (+/-)-lemildipine showed a slow onset and long duration of Ca2+ antagonistic action. Pretreatment with (-)-lemildipine and (+/-)-lemildipine for 30 min inhibited the contractions produced by 5-hydroxytryptamine and endothelin-1 with pD2 values between 6.0-8.5, whereas (+)-lemildipine and nifedipine were less potent. Of the lemildipine enantiomers, (+)-lemildipine at a low concentration (1 nmol/l) had a slight but significant Ca2+ agonistic action. However, (+)-lemildipine had no apparent effect on the pCa-tension relationship in the dog basilar artery permeabilized with Staphylococcus aureus alpha-toxin. Enantiomers of lemildipine as well as nifedipine competitively antagonized the specific binding of (+)-[3H]PN 200-110 (isradipine) to the membranes of pig coronary artery in the following order: (-)-lemildipine > nifedipine > (+/-)-lemildipine > (+)-lemildipine. These results suggest that the stereo-selective Ca2+ antagonistic actions of lemildipine enantiomers and nifedipine assessed in the functional experiments were well correlated with their potencies for the competition with the (+)-[3H]PN 200-110 binding to the pig coronary artery.

Animals↗
PubMed1995

Y-shaped lower bilateral incisors. A previously undescribed oral malformation.

A case of Y-shaped lower bilateral central incisors found in an 18-year-old Japanese man is reported. Each of the central incisors had an abnormally high cusp located at the labial surface. The cause of this malformation of the lower central incisors is obscure, but we suspect that it was due to hyperplasia of the labial surface of the central lobe of the incisor during tooth development.

Adolescent↗
PubMed1994

Allosteric interaction of semotiadil fumarate, a novel benzothiazine, with 1,4-dihydropyridines, phenylalkylamines, and 1,5-benzothiazepines at the Ca(2+)-channel antagonist binding sites in canine skeletal muscle membranes.

We assessed the binding characteristics of a benzothiazine Ca(2+)-channel antagonist, semotiadil, in canine skeletal muscle membranes. Semotiadil inhibited binding of (+)-[3H]PN 200-110 (maximum inhibition 80%), and almost completely inhibited binding of both (-)-[3H]desmethoxyverapamil and D-cis-[3H]diltiazem to their specific binding sites with an IC50 value of 0.2-2 microM and a Hill slope of 0.6-0.9. Saturation isotherm and dissociation kinetic studies suggest that semotiadil acts as a noncompetitive inhibitor at the 1,4-dihydropyridine, phenylalkylamine, and benzothiazepine (BTZ) recognition sites in the L-type Ca2+ channel: (a) Scatchard analysis showed that semotiadil decreased maximum binding (Bmax) of the three classes of Ca2+ channel antagonists, while causing a slight increase in the equilibrium dissociation constant (Kd) in the case of (+)-[3H]PN 200-110 binding or no significant change in Kd values for binding of (-)-[3H]desmethoxyverapamil and D-cis-[3H]diltiazem to their specific binding sites; and (b) dissociation kinetics of the (+)-[3H]PN 200-110 and D-cis-[3H]diltiazem bindings were accelerated by semotiadil. These results suggest that semotiadil has a strong negative allosteric interaction with three classes of Ca2+ channel antagonists, including 1,4-dihydropyridines, phenylalkylamines, and BTZ at their specific binding sites.

Allosteric Regulation↗
PubMed1992

Retrospective evaluation of surgical intervention following chemo- and radiotherapy of maxillary sinus cancers.

During the past 15 years, 30 patients with squamous cell carcinomas of the maxillary sinus were treated by modified partial maxillectomy following chemo- and radiotherapy, taking care to preserve facial contour and function as far as possible. Follow-up evaluation showed that local recurrences, and regional lymph node and distant metastases were more frequent in T4 patients than in T3 patients. Evaluation of the histopathological effects of preoperative chemo- and radiotherapy at the time of surgery showed that T4 patients tended to have a poorer response to the treatment than T3 patients. Analysis according to the direction of primary tumor extension showed that the incidence of local recurrence was higher in the superolateral type, whereas that of regional lymph node metastasis was higher in the medial type. The cumulative 5-year survival was high (72.2%) in Stage III patients and low (22.5%) in Stage IV patients. The overall rate was 55.4%. The treatment produced relatively good outcomes in T3 patients but poor outcomes in T4 patients. These findings indicate that T4 carcinoma of the maxillary sinus must be managed initially by a combination of irradiation and multi-chemotherapeutic drugs, and then treated by more extensive surgical resection.

Adult↗
PubMed1991

Pathological study of the hyperplastic dental follicle.

Eleven specimens of hyperplastic dental follicles were studied clinicopathologically, with reference to the patient's sex and age at the time of diagnosis, site of the lesions, and histopathology. The patients comprised 6 males and 5 females with an average age of 15.7 years (range 10 to 23 years). Two cases involved multiple lesions, and 9 a single lesion. The lesions were related to impaction of the canine, second premolar, second molar or third molar. Radiographically, the lesions showed various degrees of radiolucency around the crown of the impacted tooth. Most of the cases were diagnosed clinically as dentigerous cyst. The histopathological features of the lesions were similar to those of normal dental follicular tissue around the developing tooth. No tumorous features such as odontogenic fibroma, odontogenic myxoma or myxofibroma were evident in the lesions.

Adolescent↗
PubMed1991

Clinical course of multiple primary oral cancer: three of 13 cases with second primary tumor.

Of 124 patients with oral squamous cell carcinomas treated during the past 14 years, 13 developed second primary cancers with clinical symptoms in the same tissues or in organs different from those of the initial lesions during follow-up. The second primary tumors also appeared in the oral cavity in 3 of the patients, the hypopharynx in 1, the esophagus in 2, the stomach in 2, the colon in 1, the thyroid gland in 2 and the lung in 2. Of the 3 patients with second tumors in the oral cavity, 1 underwent surgery after chemo- and radiotherapy and 2 underwent laser surgery or chemo- and radiotherapy only. The second primary cancers appeared on the contralateral or ipsilateral side, completely separate from the sites of the primary lesions during a period of 1 to 3 years. One patient with triple cancers involving the oral cavity, esophagus and hypopharynx is still alive after 15 years. The other two patients died of cervical or lung metastases after 3 years.

Adult↗
PubMed1990

Mutagenicity of cadmium, platinum and rhodium compounds in cultured mammalian cells.

The induction of mutation by cadmium chloride (CdCl2), platinum tetrachloride (PtCl4), and rhodium trichloride (RhCl3.3H2O) was measured utilizing the hypoxanthine-guanine phosphoribosyl transferase (HGPRT) locus in V-79 cells. Cadmium chloride at a concentration of 0.05 microM induced ford mutation in V-79 cells 4 times that of their control mutation frequency. Platinum tetrachloride at a concentration of 15 microM and 300 microM rhodium trichloride also induced ford mutation in V-79 cells at rates of around 7 and 4 times control rates, respectively. Platinum is often, and rhodium sometimes added to dental metallic alloys to improve their metallurgic characteristics and cadmium has been mingled in such alloys as well. Moreover, metallic dental drugs such as K2PtCl4 are used a dentine desensitizers. Thus, the genetic hazards of metal ions including cadmium, platinum, and rhodium that dissolve from dental materials and drugs must be investigated and caution exercised for their safe use in dental clinics.

Animals↗
PubMed1984

[Undifferentiated carcinoma of the thyroid gland with osteoclast-like giant cells--a case report].

A case of undifferentiated carcinoma of the thyroid gland with osteoclast-like giant cells resembling those of a giant cell tumor of the bone is presented. A 79-year-old female had noticed swelling on the left frontal neck. Histological examination of frontal-neck tumor revealed undifferentiated carcinoma of the thyroid gland. The patient was treated with a Cobalt 60 unit and received a total tumor dose of 2800 rad. However, because of a rapid increase in size of the tumor and its metastasis, the patient died about 2 months after admission. An autopsy was performed. Histologically, the tumor differed from the usual undifferentiated carcinoma of the giant cell type in having osteoclast-like giant cells with many small, uniform, benign appearing nuclei. It is proposed that the osteoclast-like giant cell is reactive rather than neoplastic in nature because of the benign appearance, phagocytotic activity and some ultrastructural features.

Aged↗
PubMedDate not supplied

Utilization of cell response under heat, chemical, and combined stresses for selective recovery of cytoplasmic beta-galactosidase from Escherichia coli cells.

The effective bioseparation process was developed by exploiting the cell response under heat, chemical, and combined stresses for selective recovery of cytoplasmic beta-galactosidase from Escherichia coli cells. At the observed optimal condition for heat stress (45 degrees C, 30 min) and that for chemical stress (20 mM Triton X-100, 5 mM EDTA, 30 min), E. coli cells were exposed to these stresses either simultaneously or sequentially. The operational sequence highly affected the yield and selectivity of the target recovery. Exposing the cells to the sequential stress (heating at 45 degrees C for more than 30 min after Triton X-100/EDTA treatment for 30 min) was found to be most effective for selective recovery of target beta-galactosidase among possible sequences.

Biotechnology↗
PubMedDate not supplied

Intraosseous neurilemmoma of the mandible.

We report a rare case of intraosseous neurilemmoma of the mandible, with an emphasis on radiographic findings. The tumor, located mainly in the premolar region, presented as an expansive, unilocular, well-defined, radiolucent lesion on plain radiography. No dilatation of the mandibular canal was identified. MR imaging helped to identify the solid nature of the tumor. A biopsy was necessary to make the final diagnosis because of the relatively nonspecific nature of the lesion.

Adult↗