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T Mizunuma

Publications and source records attributed to T Mizunuma.

At least 19 recordsLinked to original sources
PubMed1999

The effect of intravenous or subarachnoid lidocaine on glutamate accumulation during transient forebrain ischemia in rats.

UNLABELLED: We studied whether IV or subarachnoid (SA) lidocaine would influence the increase in extracellular glutamate concentration in the hippocampal CA1 and the cerebral cortex during transient forebrain ischemia in rats by using the dialysis electrode method. Fifty-four Sprague-Dawley rats were assigned to one of six treatment groups: IV lidocaine 5 mg/kg, IV lidocaine 10 mg/kg, IV 0.9% saline 0.5 mL/kg, SA lidocaine 5 mg/kg, SA lidocaine 10 mg/kg, and SA 0.9% saline 0.5 mL/kg (n = 9 in each group). Transient forebrain ischemia was induced by hemorrhagic hypotension and carotid artery occlusion, 15 min after administration of lidocaine or saline. The maximal values of glutamate concentration and the areas under glutamate concentration curves in the CA1 were significantly less in the IV lidocaine 10 mg/kg group than the IV saline group, whereas those in the CA1 and the cortex were significantly less in the SA lidocaine 5 and 10 mg/kg groups than the SA saline group. The accumulation of glutamate in the CA1 or the cortex during transient forebrain ischemia was attenuated by IV or SA lidocaine. We conclude that the neuroprotective effect of lidocaine against transient cerebral ischemia involves the suppression of the increase in extracellular glutamate concentration. IMPLICATIONS: IV or subarachnoid lidocaine was demonstrated to suppress glutamate accumulation in the hippocampus and the cortex during transient forebrain ischemia in rats by using the dialysis electrode method. Lidocaine can have a neuroprotective effect through the suppression of the increase in extracellular glutamate concentration.

Anesthetics, Local↗
PubMed1998

[Changes in the threshold values of lingua throughout aging].

The filter-paper-disk method was employed for measuring the threshold values of four basic taste on lingua-tip with 308 healthy females aged 20-79. Taste substance were sequentially diluted with distilluted water (30 stages from 80.0 g/dl for sucrose, 30 stages from 30.0 g/dl for NaCl, 30 stages from 8.0 g/dl for sodium tartrate, 30 stages from 4.0 g/dl for HCl quinine). The result was as follows. A sensibility of gustation decreased rapidly in accordance with aging. A decrease of bitterness sensibility was most remarkably with aging, succeeded sourness, sweetness, saltyness. Also, a decrease of a gustation sensibility is beginning in early twenties, especially the sensitivity to a sweetness and sour taste decreased conspicuously from twenties to thirties.

Adult↗
PubMed1998

[Studies on the influence of riboflavin intake to osteogenesis in rats].

Influence of an intake of the riboflavin that exerts upon osteogenesis in this research, was examined by a nutritional methods. It search the condition of femur in rats they reared and given three type riboflavin dosage, namely, sufficient riboflavin, few deficient riboflavin and administered sufficient after few deficient riboflavin. As a result, an influence of riboflavin dosage was not recognized about each of the body weight, food intake, and weight and length of femur. In other words, a deficiency symptom was not observed seemingly in the rat that given riboflavin deficiency diet. Also, the calcium contents in the femur decreased significantly by the deficiency of riboflavin. And, the low value was shown the even in the rat that administered sufficient fibroflavin later. Furthermore, even breaking force of the femur decreased by the deficiency of riboflavin.

Animals↗
PubMed1997

[Studies on the taste perceptive threshold for 4 basic taste qualities at various sites of lingual surface].

Using filter-paper-disk method for 20 approximately 23 year-old 60 healthy females, taste perceptive thresholds for 4 basic taste qualities (sweetness, saltiness, sourness and bitterness) were measured detailedly at various sites of the lingual surface (lingual apex, lingual center, lingual margin, lingual radix). Sucrose, sodium chloride, sodium tartarate and quinine hydrochloride as taste-producing substances were used for the sweetness, saltiness, sourness and bitterness, respectively. The results revealed the apical site to be most sensitive to all of the sweetness, saltiness and sourness (and especially to the saltiness) and to be followed by marginal and radical sites in sensitiveness. The radical site was revealed to be most sensitive only to the bitterness, and the central site was remarkably hyposensitive to all of these taste qualities. These experimental results differ, in many respects, from those results of study which have been published by Kiesow in 1894 and are already established today (lingual sensitivity to taste qualities is found separately by site: sweetness, sourness and bitterness and highly perceptible at apical, marginal and radical sites, respectively, and saltiness is not very differently perceptible by site), indicating that further detailed reexamination will be needed to know how taste perceptive thresholds for 4 basic taste qualities are distributed in the lingual surface.

Adult↗
PubMed1996

Levels of pulmonary surfactant protein A in fetal lung and amniotic fluid from protein-malnourished pregnant rats.

Surfactant protein A (SP-A) is a major apo-protein of pulmonary surfactant, which lines the alveolar walls, lowering the surface tension to prevent lung collapse. Pregnant rats were divided into two groups which received a diet with either 5% or 20% protein from gestational day 9. By a sensitive immunoassay, SP-A levels in the fetal lungs and the amniotic fluid showed a dramatic increase with advancing gestation after the initial appearance on gestational day 18 in both diet groups. Significantly lower levels of SP-A in pregnant rats fed 5% protein diet than those in pregnant rats fed 20% protein diet were observed in the fetal lungs on gestational day 21 and in the amniotic fluid on gestational days 20 and 21. The profiles of increased SP-A levels in the amniotic fluid reflected those in the fetal lungs during gestation. Immunohistochemical examination with anti-rat SP-A antibody at 21 days of gestation showed that the immunoreactive staining of bronchiolar epithelial Clara cells and alveolar type II cells were weaker in the fetal lung sections from pregnant rats fed 5% protein diet than in those from pregnant rats fed 20% protein diet. It is concluded that protein malnutrition in pregnant rats affects the biosynthesis of SP-A in the fetal lungs, which may have important consequences for prematurity and decreased respiratory functions in the neonatal lungs at birth.

Amniotic Fluid↗
PubMed1996

[Subarachnoid administration of lidocaine reduces delayed neuronal damage due to forebrain ischemia in rats].

We examined the effect of subarachnoid administration of lidocaine on delayed neuronal damage due to forebrain ischemia in rats. Sixteen rats were divided at random into two groups: lidocaine group rats (n = 8) and control group rats (n = 8) were subarachnoidally administrated lidocaine 5mg.kg-1 and normal saline, respectively, prior to ischemia. Forebrain ischemia was induced by bilateral carotid artery occlusion combined with systemic hypotension for 10 min. Cerebral perfusion-fixation was performed 7 days after ischemia, subsequent to which the brains were sectioned coronally and stained with celestine blue/acid fuchsin. In the neocortex and the hippocampal CA4 region, the lidocaine group showed less ischemic neuronal injuries than the control group. However, in the hippocampal CA1/CA3 regions and the caudoputamen, neuronal injuries in the lidocaine group were not significantly different from those in the control group. We conclude that the pre-ischemic subarachnoid administration of lidocaine reduces the delayed neuronal damage in neocortex and hippocampal CA4 region in the rat with forebrain ischemia.

Anesthetics, Local↗
PubMed1996

Immunohistochemical localization of surfactant protein A in N-bis (2-hydroxypropyl) nitrosamine-induced lung tumors in rats.

Surfactant protein A (SP-A) is most abundant protein associated with pulmonary surfactant which is synthesized by alveolar type II cells in the alveoli. In this study, we localized SP-A in experimentally induced pulmonary hyperplasias and tumors in rats, by immunohistochemistry. When rats were given a single intraperitoneal injection of N-bis (2-hydroxypropyl) nitrosamine (BHPN) followed by exposed to mixture gases of O3 and NO2, hyperplastic alveolar type II cells stained with the antibody against SP-A were located in the alveolar walls near the alveolar ducts. Adenomas and adenocarcinomas were stained with the anti-SP-A antibody in the lung parenchyma. These immunohistochemical findings suggested that the lung tumors induced in rats treated with BHPN and additionally exposed to mixture gases of O3 and NO2 are derived from mainly alveolar type II cells.

Animals↗
PubMed1992

[Is a portable disposable pump useful in managing postoperative pain?].

In order to find out the effectiveness of continuous epidural infusion with a portable disposable pump (Baxter Infusor) in management of post-operative pain, a comparative study was made on a continuous epidural infusion method with a syringe pump versus a twice-a-day intermittent epidural infusion method. Study 1: With 41 patients who underwent thoracic/abdominal surgery between June, 1991 and September, 1991, researches were conducted on the effects of pain relief, methods for postoperative pain relief and weaning course from confinement to bed. The degree of pain examined at five points--at 4 hours, 12 hours, 16 hours, 24 hours and 28 hours postoperatively--indicated a significantly lower level in the Infusor group, compared with the intermittent infusion group (P less than 0.05). In terms of time required for anodyne administration, the Infusor group required significantly less time compared with the intermittent infusion group (P less than 0.05). As for weaning from bedriddenness, a tendency of earlier weaning was observed in the Infusor group, compared with the other two groups. Study 2: With a total of 37 people who were involved in postoperative management described in Study 1, including 8 surgeons and 29 surgery-ward nurses, an investigation was made through a questionnaire concerning their assessment on the 3 methods of anodyne infusion employed in Study 1. Among doctors, the evaluation of the Infusor method was remarkably high, compared with the intermittent infusion method (P = 0.001). When the syringe pump method and the intermittent method were compared, the evaluation of the syringe pump method was significantly higher (P less than 0.05). The evaluation by nurses, on the other hand, was remarkably higher on the infusion method than on the other two methods (P = 0.0001). Based on the results of the two studies summarized above, the Infusor method is considered to be most effective for pain control among the three methods.

Analgesia, Epidural↗
PubMed1992

[The effects of induced hypotension with sevoflurane and PGE1 on liver functions during neurosurgery].

The effects of induced hypotension with sevoflurane and PGE1 (Group S) on liver functions during neurosurgery that can avoid direct invasion of the liver were retrospectively studied in 35 cases, in comparison with 8 cases of isoflurane and PGE1 induced hypotension (Group I). GOT, GPT and gamma-GTP increased slightly in both groups 1 day and 1 week after operation, but they returned to preoperative levels 1 month later. ChE decreased in both groups, and the decrease was greater in group S. Three cases in Group S (8.6%) and one case in Group I (12.5%) showed GOT or GPT over 100 and there was no significant difference in the two groups. Hypotensive anaesthesia induced with sevoflurane and PGE1 in neurosurgery, as that induced with isoflurane and PGE1, has little effect on postoperative liver functions.

Aged↗
PubMed1985

[Bonded bridges].

Explore the source record for details and available documents.

Adhesives↗
PubMed1984

Effects of injecting excess arginine on rat pancreas.

When male rats were given single i.p. injection of 500 mg of L-arginine/100 g body weight, the pancreatic acinar cells were destroyed selectively, without any morphological change of Langerhans' islets. As early as 24 hours after the injection, loss of basophilia, zymogen degranulation, and vacuolar and necrotic changes of the acinar cells were noted. After 3 days, fibroblastic activity and atrophy of pancreatic lobuli were evident. Early electron microscopic findings were changes of the endoplasmic reticulum, such as partial dilatation or vacuolation of the cisternae, usually with loss of ribosomes attached to the membrane. The effect of arginine excess may be ascribed to imbalance of amino acids and subsequent to decrease of protein synthesis in the acinar cells. In the course of this study, fat necrosis with marked infiltration of leucocytes was observed in adipose tissues in peripancreatic, epididymal, omental and retroperitoneal areas. This change correlated closely with the marked necrosis of the pancreas. An increase in the level of lipase in the blood was also demonstrated.

Amylases↗
PubMed1982

Effects of choline deficiency and phosphatidylcholine on fat absorption in rats.

Transfer of lipid to the lymph by the intestine was studied in rats fed on choline-deficient or choline-supplemented diet for 2 weeks. In choline-deficient rats, lymph output was reduced. Choline deficiency impaired the incorporation of glycerol tri[1-14C]oleate into triglyceride in the lymph. The triglyceride level in lymph lipoproteins was lower in choline-deficient rats than in controls. Ultrastructural studies suggested that impaired release of lipoproteins was responsible for accumulation of fat in intestinal absorptive cells. These defects are probably related to changes in the membrane system of the intestine and to a failure in lipid droplet movement within absorptive cells, resulting from alterations in the microfilaments. Oral administration of phosphatidylcholine to rats on choline-deficient diet rapidly improved the decreased lymph output and the impaired incorporation of glycerol tri[1-14C]oleate into triglyceride and reduced fat deposition in intestinal epithelial cells. In conclusion, phospholipids such as choline are confirmed as being extremely important in the absorption of fat by the possible mechanism of fat transport across the membrane.

Animals↗
PubMed1981

Effect of amino acids on insulin-stimulated glucose metabolism in fat cells.

The effect of amino acids on insulin responsiveness in epididymal adipose tissue was examined. It was found that insulin-stimulated glucose oxidation in fat cells was significantly inhibited by glycine, alanine, valine, leucine, isoleucine, cysteine, methionine, lysine, phenylalanine, and proline. The effect of insulin on glucose incorporation into triglyceride is also severely diminished by these amino acids. In addition, alanine reduced the incorporation of precursors ([U-14C]glucose or [1-14C]palmitate) into triglyceride both in vitro and in vivo. The Ki values of alanine were 0.4 and 0.5 mM toward the precursors of glucose and palmitate, respectively. The mechanism of reduction of insulin responsiveness in rat adipose tissue is discussed on the basis of these results.

Adipose Tissue↗
PubMed1980

Antagonism between osmophilic lactic Acid bacteria and yeasts in brine fermentation of soy sauce.

Brine fermentation by osmophilic lactic acid bacteria and yeasts for long periods of time is essential to produce a good quality of shoyu (Japanese fermented soy sauce). It is well known that lactic acid fermentation by osmophilic lactic acid bacteria results in the depression of alcoholic fermentation by osmophilic yeasts, but the nature of the interaction between osmophilic lactic acid bacteria and yeasts in brine fermentation of shoyu has not been revealed. The inhibitory effect of osmophilic lactic acid bacteria on the growth of osmophilic yeasts was investigated. It was recognized that osmophilic shoyu yeasts such as Saccharomyces rouxii and Torulopsis versatilis were inhibited by a metabolite produced by osmophilic lactic acid bacteria (belonging to Pediococcus halophilus) in brine fermentation of shoyu. The primary inhibitor was considered to be acetic acid, although lactic acid was slightly inhibitory.

Journal Article↗