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H Tsuchida

Publications and source records attributed to H Tsuchida.

At least 37 records · Page 2Linked to original sources
PubMed2000

[Endogenous D-serine in mammalian brains].

It is well established that, like glycine and D-alanine, D-serine potentiates glutamate neurotransmission via the N-methyl-D-aspartate (NMDA) receptor by selective stimulation of its strychnine-insensitive glycine site and acts as a co-agonist of the glutamate receptor. D-Serine has been found to modify behavioral changes associated with higher brain functions such as memory, convulsion, anxiety, psychotomimetic-induced abnormal behavior and cerebellar ataxia. Interestingly, a substantial amount of free D-serine has been demonstrated in mammalian brains, although it has long been presumed that D-amino acids are uncommon in mammals. Free D-serine is predominantly concentrated in the brain with a persistent high content throughout life. The patterns of the regional variations and the postnatal changes in brain D-serine are closely correlated with those of the R2B subunit of the N-methyl-D-aspartate (NMDA) type excitatory amino acid receptor. Moreover, D-serine is released to the extracellular space and taken up into the brain homogenates, C6 glioma cells and primary culture of astrocytes of the rat cerebral cortex. Recently, the conversion of L-serine to its D-form by serine racemase has been suggested by in vivo and in vitro experiments. These data are consistent with the view that D-serine might be an intrinsic positive modulator of the brain NMDA receptor containing the R2B subunit and play a pivotal role in controlling behavioral expression in mammals.

Animals↗
PubMed2000

[A case study of BRON (cough suppressant) tablet dependence--its social psychiatric and biological aspects].

A case of BRON tablet dependence is demonstrated. BRON is an over-the-counter (OTC) cough suppressant, which contains methylephedrine, dihydrocodeine, chlorpheniramine and caffeine. He took BRON tablet for the first time at the age of 16. In progress, he developed psychomotor excitement twice and finally manifested amotivational syndrome 3 years later from his first use. Longitudinal 123I-IMP SPECT (autoradiography method) findings demonstrated diffuse cerebral blood flow (CBF) decrease and relative hyperactivity in the lower frontal lobe. Diffuse decreased regional CBF, which was unchanged through its course for about 4 months, may show irreversible brain damage due to chronic BRON abuse. The findings of relative hyperactivity in the lower frontal lobe (orbitofrontal lobe) may reflect "craving for BRON" based on abnormal dopaminergic neural system activity. Based on the evidence that orbitofrontal hyperactivity is also seen in cases of cocaine abuse, methylephedrine, which is a cocaine-like central nervous system stimulant, may play the main role in BRON dependence formation. In Japan, BRON syrup abuse and dependence were in fashion for youth in 1980s. After the legal regulation of the market in 1988, it has gone out of fashion. While it is still easy to acquire OTC cough suppressant, reports of BRON tablet abuse and dependence are quite rare through 1980s and 1990s. This case suggests that BRON tablet abuse also could lead to dependence and come into new vogue for youth in the future. We should pay attention to the trend of OTC cough suppressant abuse and may need to regulate the market by law more severely.

Adolescent↗
PubMed1999

2'-Pyrene modified oligonucleotide provides a highly sensitive fluorescent probe of RNA.

Oligonucleotide 9mers containing 2'-O-(1-pyrenylmethyl)uridine [U(pyr)] at the center position were synthesized by using a protected U(pyr) phosphoramidite. The UV melting behaviors indicate that the pyrene-modified oligonucleotides can bind to both their complementary DNA and RNA in aqueous solution. When compared with the unmodified oligonucleotides, the pyrene-modified oligonucleotides showed higher affinity for DNA while exhibiting lower affinity for RNA. The pyrene-modified oligonucleotides in diluted solution exhibited fluorescence typical of pyrene monomer emission [lambdamax 378 (band I) and 391 nm (band III)]. When these oligomers bound to DNA, the fluorescence intensity ratio of band III/band I was increased. With this fluorescence change, a new broad emission (lambdamax 450 nm) due to exciplex between the pyrene and an adjacent nucleobase appeared. In contrast, addition of RNA to the pyrene oligonucleotides resulted in enhancement of the pyrene monomer emission with decrease in the fluorescence band ratio. The extent of the emission enhancement was found to be highly dependent on the nucleobase adjacent to the U(pyr) in the pyrene oligomers. The pyrene oligonucleotide containing dC at the 3'-site of the modification showed remarkable increase (approximately 250 times) in fluorescence (375 nm) upon binding to complementary RNA. The present findings would open the way to the design of a highly sensitive fluorescent probe of RNA.

Circular Dichroism↗
PubMed1999

Effect of ACE gene on diabetic nephropathy in NIDDM patients with insulin resistance.

We investigated the influence of the angiotensin-converting enzyme (ACE) gene on the onset and/or progression of diabetic nephropathy in 62 Japanese patients with non-insulin-dependent diabetes mellitus (NIDDM; type II diabetes). Because a number of factors are believed to be involved in the onset and/or progression of diabetic nephropathy, especially in patients with NIDDM, we selected the patients with well-matched risk factors, duration of disease, glycemic control, blood pressure, and others. All patients had normal renal function and none were receiving ACE inhibitors. Patients were divided into three groups according to albumin excretion rate (AER): group A, patients with an AER less than 15 microg/min (n = 29); group B, patients with an AER between 15 and 70 microg/min (n = 19); and group C, patients with an AER greater than 70 microg/min (n = 14). The glucose disposal rate was estimated using a euglycemic hyperinsulinemic clamp. We determined the mean glucose disposal rate in 132 patients with NIDDM (6.49 mg/kg/min). Patients with a glucose disposal rate less than the mean rate were considered to have a high degree of insulin resistance (n = 36). The presence of an insertion/deletion (I/D) polymorphism of the ACE gene was determined by the polymerase chain reaction method. Among patients with a high degree of insulin resistance, diabetic nephropathy was present in 2 of 11 patients with the II genotype of the ACE gene compared with 19 of 25 patients with the ID or DD genotype (P = 0.0024). The prevalence of diabetic nephropathy was greater in patients with both significant insulin resistance and the D allele (19 of 25) than in the remaining patients (14 of 37; odds ratio, 5.20). These results suggest that the ACE gene influences the onset and/or progression of diabetic nephropathy in patients with NIDDM with significant insulin resistance.

Diabetes Mellitus, Type 2↗
PubMed1999

The effect of propofol and thiamylal on hypertensive responses to a rapid increase in isoflurane concentration.

STUDY OBJECTIVE: To compare the effects of propofol and thiamylal on the hyperdynamic circulatory response caused by a rapid increase in isoflurane concentration. DESIGN: Prospective, randomized, double-blind study. SETTING: Operating rooms of a university hospital. PATIENTS: 30 ASA physical status I adult patients scheduled for elective surgery with general anesthesia. INTERVENTIONS: Patients were anesthetized with either propofol 2 mg/kg (propofol group, n = 15) or thiamylal 4 mg/kg (thiamylal group, n = 15). Two minutes after anesthesia induction, the inspired isoflurane concentration was rapidly increased from 0.5% to 5% and maintained for 5 minutes. MEASUREMENTS AND MAIN RESULTS: Mean arterial pressure significantly increased after the increase in isoflurane concentration in the thiamylal group, but it did not change in the propofol group. The isoflurane-induced increase in rate-pressure product was significantly greater in the thiamylal group than in the propofol group. CONCLUSION: Propofol induction of anesthesia more effectively attenuates the circulatory responses to a sudden increase in isoflurane concentration than does thiamylal.

Adult↗
PubMed1999

Autolysis of lentinan, an antitumor polysaccharide, during storage of Lentinus edodes, shiitake mushroom.

The lentinan contents in the Lentinus edodes fruit body during storage were examined by ELISA method using anti-lentinan antibodies. The lentinan content (12.8 mg.g(-)(1) dw) before storage decreased to 3.7 mg.g(-)(1) dw over 7 days at 20 degrees C. However, it only slightly decreased at 1 degrees C and only decreased to 9.3 mg. g(-)(1) dw at 5 degrees C. Glucanase activity, which seems to be associated with lentinan degradation, increased more during storage of L. edodes at 20 degrees C than it did at lower temperatures. In addition, only glucose was detected as a degraded product from lentinan by the glucanase. This suggested that this enzyme would fit the profile of an exo-type glucanase. Also, polyphenol oxidase activity, known as an index of freshness reduction in the mushroom, increased approximately 2.7-fold (to 61.5 units.mg(-)(1)) over 7 days during storage at 20 degrees C. However, its activity changed little during storage at lower temperatures. These results indicate that the reduction during storage of the quality of L. edodes as a functional food is accompanied by the decrease of lentinan, and by browning, and that exo-glucanase plays an important role in the decrease of lentinan content.

Enzyme-Linked Immunosorbent Assay↗
PubMed1999

The direct effect of halothane on myocardial contraction in rat myocytes with poorly developed gap junctional intercellular communication.

BACKGROUND: The gap junction channel plays an important role in synchronous beating in the heart, and the reduction in the amount of gap junctional intercellular communication (GJIC) is thought to be the main arrhythmogenic factor in diseased heart. However, the effect of halothane on myocardial contraction in heart tissue with less GJIC is not well known. The purpose of the present study is to examine the direct effect of halothane on myocardium with poorly expressed GJIC. METHODS: Ventricular myocytes were obtained from neonatal rats by enzymatic digestion with collagenase and then cultured for 3 or 7 d. We have previously reported that the number of gap junctions at 3 d is approximately 10% of that at 7 d (1). The myocytes were stabilized in serum-free medium, and the spontaneous beating rate and amplitude were measured by a fiberoptic sensor. RESULTS: Heptanol (2 mM), an inhibitor of GJIC, abolished synchronized beating in myocytes cultured for 7 d. Halothane decreased the beating rate and amplitude in both groups of myocytes in a concentration-dependent manner (P < 0.05). Halothane at 1 and 2 MAC (adult rat MAC) decreased the beating rate more in myocytes cultured for 3 d than in myocytes cultured for 7 d (P < 0.05). Halothane reduced beating amplitude equally in both groups. Asynchronous contraction developed more frequently among myocytes cultured for 3 d than for those at 7 d. CONCLUSION: Halothane may block the GJIC channels, and when the number of these channels is reduced, exposure to halothane may cause asynchronous beating and decrease the beating rate. However, the halothane-induced decrease in amplitude is probably not due to blockade of GJIC because reducing the number of GJIC channels did not alter halothane's depressant effect.

Anesthetics, Inhalation↗
PubMed1999

High-level expression of maize phosphoenolpyruvate carboxylase in transgenic rice plants.

Using an Agrobacterium-mediated transformation system, we have introduced the intact gene of maize phosphoenolpyruvate carboxylase (PEPC), which catalyzes the initial fixation of atmospheric CO2 in C4 plants into the C3 crop rice. Most transgenic rice plants showed high-level expression of the maize gene; the activities of PEPC in leaves of some transgenic plants were two- to threefold higher than those in maize, and the enzyme accounted for up to 12% of the total leaf soluble protein. RNA gel blot and Southern blot analyses showed that the level of expression of the maize PEPC in transgenic rice plants correlated with the amount of transcript and the copy number of the inserted maize gene. Physiologically, the transgenic plants exhibited reduced O2 inhibition of photosynthesis and photosynthetic rates comparable to those of untransformed plants. The results demonstrate a successful strategy for installing the key biochemical component of the C4 pathway of photosynthesis in C3 plants.

Gene Dosage↗
PubMed1999

Anti-tumor polysaccharide from the mycelium of liquid-cultured Agaricus blazei mill.

Anti-tumor active polysaccharide against Sarcoma 180 was isolated by DEAE-Sepharose CL-6B and Sepharose 4B column chromatography from the hot-water soluble fraction of the mycelium of liquid-cultured Agaricus blazei mill. This polysaccharide did not react with antibodies of anti-tumor polysaccharides such as lentinan, gliforan, and FIII-2-b which is one of anti-tumor polysaccharides from Agaricus blazei. Moreover, the analyses of 13C-NMR and GC-MS suggested that this polysaccharide was preliminarily glucomannan with a main chain of beta-1,2-linked D-mannopyranosyl residues and beta-D-glucopyranosyl-3-O-beta-D-glucopyranosyl residues as a side chain. This polysaccharide was completely different from the anti-tumor polysaccharide from fruiting body of Agaricus blazei, beta-1,6-glucan.

Agaricus↗
PubMed1999

Thumb polydactyly.

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Journal Article↗
PubMed1999

[Induction of anesthesia with propofol injected through a central venous catheter].

We compared propofol injected through a central venous catheter with that through a peripheral cannula from the standpoint of injection pain, induction time and hemodynamic changes. Thirty-nine patients about to receive abdominal surgery, who had central venous catheters inserted via the subclavian vein, were included in this study. General anesthesia was induced with a loading dose of propofol 1 mg.kg-1 followed by an infusion of 10 mg.kg-1.hr-1 into the central vein without carrier intravenous fluid (group A, n = 13), the peripheral vein without carrier intravenous fluid (group B, n = 13) or the peripheral vein with rapid infusion of acetated Ringer's solution (group C, n = 13). After endotracheal intubation, anesthesia was maintained with propofol 4 mg.kg-1.hr-1. The incidence of injection pain was 53% in group B and 76% in group C, whereas none of the patients in group A felt discomfort or pain during propofol injection. The mean induction time was significantly shorter in group A (43 +/- 12 sec) than group B (66 +/- 16 sec) or group C (57 +/- 11 sec). There were no differences between each group in hemodynamic changes during induction of anesthesia. Propofol injection via central venous catheter can avoid the injection pain and shorten the induction time.

Abdomen↗
PubMed1999

Halothane attenuates nitroglycerin-induced vasodilation and a decrease in intracellular Ca2+ in the rat thoracic aorta.

UNLABELLED: Although halothane inhibits endothelium-mediated vasorelaxation, the sites of inhibition remain controversial. Because the cytosolic concentration of Ca2+ ([Ca2+]i) has crucial roles for tension development, we examined the effects of halothane on nitroglycerin-induced vasorelaxation from the standpoint of [Ca2+]i. Isolated spiral strips of rat thoracic aorta without endothelium were suspended for isometric tension recordings in a physiologic salt solution. Muscle contraction was evoked with 10(-8) M norepinephrine, followed by endothelium-independent vasorelaxation with nitroglycerin 10(-7) and 10(-6) M. The effects of halothane 1.5% and 3% on nitroglycerin-induced vasorelaxation were evaluated along with the concomitant measurement of [Ca2+]i using fura-2-Ca2+ fluorescence. In other muscle strips, incremental doses of norepinephrine were administered during halothane exposure to induce contractions comparable to those without halothane. Nitroglycerin dose-dependently reduced norepinephrine-induced muscle contractions, but the decrease in [Ca2+]i reached a plateau at 10(-7) M, which indicates that nitroglycerin induced [Ca2+]i-dependent and [Ca2+]i-independent vasorelaxation. Both concentrations of halothane inhibited nitroglycerin-induced decreases in muscle tension and [Ca2+]i, not only when the same dose of norepinephrine was used for contraction during halothane exposure, but also at incremental doses of norepinephrine. In conclusion, halothane inhibits nitroglycerin-induced vasorelaxation partly by suppressing Ca2+ changes in the smooth muscle. IMPLICATIONS: We examined nitroglycerin-induced vasorelaxation in the rat thoracic aorta, along with the concomitant measurement of the cytosolic concentrations of Ca2+, and found that halothane attenuated endothelium-independent vasorelaxation by suppressing Ca2+ dynamics in the smooth muscle.

Anesthetics, Inhalation↗
PubMed1999

Surgical management of arteriosclerotic coronary artery aneurysm.

A 60-year-old man suffered antero-septal myocardial infarction at the age of 56. Coronary angiography demonstrated total occlusion of the left anterior descending artery and a large saccular aneurysm of the right coronary artery. Diffuse coronary ectasia was also shown in the right coronary artery adjacent to the aneurysm. Despite anticoagulant therapy, the aneurysm formed a thrombus and developed coronary artery stenosis distal to the aneurysm. Ligation of the aneurysm and in situ gastroepiploic artery grafting were performed. Sudden heart failure was developed during skin closure. As this condition was considered to be graft hypoperfusion, supplemental saphenous vein grafting was placed. Ligation is a simple, reliable technique to prevent future complications for a large saccular right coronary artery aneurysm, however, gastroepiploic artery might be an inappropriate bypass conduit for the ligated coronary artery with diffuse ectasia.

Arteries↗
PubMed1999

[Intra-aortic balloon occlusion of the descending thoracic aorta for intra-abdominal hemorrhage].

Intra-aortic balloon occlusion (IABO) of the descending aorta is beneficial to rescue patients in shock following traumatic intra-abdominal hemorrhage. The authors experienced four such patients who had received IABO of the descending thoracic aorta to maintain hemodynamics prior to operation. After hemostasis, the balloon was deflated gradually. Releasing the balloon in the operating room was, however, abandoned in two patients because of severe deoxygenation and life threatening arrhythmia. In the other two patients, the balloon was successfully deflated during the operations; one of them died a week later from multiple organ failure. We conclude that shortening the aortic occlusion time as well as the treatments for adverse effects of balloon release are important in the anesthetic management of patients receiving IABO.

Abdomen↗
PubMed1999

[Mental and physical symptoms in alcoholics after alcohol withdrawal--comparing with involutional melancholia patients].

As a factor of recurrence of drinking in patients with alcoholic dependence, emotional disorders accompanied by alcohol dependence has been noted in many reports. Particularly, it is noted to be very likely that depression after abstinence is an incentive to re-start drinking. In this study, we investigated depressive feeling in aspects of psychiatric and physical subjective symptoms after abstinence in patients with alcohol dependence, and compared the symptoms with those in patients with involutional depression. On analysis of the major component of psychiatric subjective symptoms, a sense of alienation, emotional instability, anxiety, and aggressiveness were observed. In involutional depression, depressive feeling, somnipathy, anxiety, self accusation/sense of guilt, delusion of culpability were observed. On analysis of the major component of physical subjective symptoms, autonomic nervous symptoms accompanied by feebleness, hysterical neurosis-like autonomic nervous symptoms, reduced sexual libido, anorexia, hydrodipsia/sweating were observed. Similarly, in patients with involutional depression, hysterical neurosis-like autonomic nervous symptoms, anorexia, elevation of tonus, general malaise, and hydrodipsia were noted. Differences in status were emphasized in comparison between the two groups in both analyses. Unlike involutional depression that exhibits the current features of depression, patients with alcohol dependence showed a sense of alienation, emotional instability, anxiety, and aggressiveness, reflecting self-uncertainty and loss of self-respect. Drinking may be re-started to relieve or reduce tension and frustration in such conditions.

Alcoholism↗
PubMed1998

The usefulness of celite-activated thromboelastography for evaluation of fibrinolysis.

PURPOSE: Although thromboelastography is useful for measuring both coagulability and fibrinolysis, it takes about two hours to measure all parameters including fibrinolytic rate. The present study aimed to investigate the usefulness of celite-activated thromboelastography (TEGc) to evaluate fibrinolytic status in non-cardiac surgery. METHODS: Whole blood samples were obtained from 30 patients for non-cardiac surgery, and used for measurements of both native TEG (TEGn) and TEGc. The final concentration of 1% (w/v) celite was used for TEGc. RESULTS: Time for measurement of the fibrinolytic rate (FR) of TEGc in patients (56.7 +/- 4.0 min) was less than half that of FR of TEGn (123.3 +/- 15.6 min) (P < 0.05), suggesting a more rapid assessment of fibrinolytic status. A linear relationship was observed between FR values of TEGc and those of TEGn (r = 0.93, P < 0.0001), suggesting the usefulness of the fibrinolytic parameter of TEGc. CONCLUSION: TEGc is a useful technique for a more rapid assessment of fibrinolytic status.

Adult↗