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H Tsuchida

Publications and source records attributed to H Tsuchida.

At least 19 recordsLinked to original sources
PubMed2001

Cloning of a D-serine-regulated transcript dsr-1 from the rat cerebral cortex.

To obtain insight into the molecular mechanisms underlying the metabolism and functions of endogenous d-serine, we have explored d-serine-regulated transcripts in the neocortex of the infant rat treated with acute d-serine administration by using an RNA fingerprinting technique. Cloning and sequence analysis of the corresponding cDNAs to the identified transcripts have revealed that the dsr-1 (d-serine responsive transcript-1) mRNA is presumed to contain a novel sequence at the 5'-region, while the 631-base nucleotide sequence of its 3'-end is identical with that of rat M9.2 mRNA encoding a subunit of vacuolar type proton-ATPase. The predicted two open reading frames and their deduced amino acid sequences suggest that the dsr-1 product has a membrane spanning domain. The dsr-1 transcript was detected as a single band around 2.1 kb on the Northern blot. RT-PCR analyses have indicated that the dsr-1 transcript is expressed predominantly in the brain, lung, and testis, and that acute intraperitoneal injection of d-serine significantly upregulates dsr-1 expression in the neocortex 3 and 15 h later without affecting the levels of the M9.2 gene transcript. These results suggest that dsr-1 products may be involved in the d-serine-related metabolic or signaling pathways in mammalian brains.

Amino Acid Sequence↗
PubMed2000

Propofol improves recovery from paraquat acute toxicity in vitro and in vivo.

OBJECTIVE: To investigate whether the antioxidative sedatives propofol and thiopental can improve recovery from acute paraquat toxicity in A549 cells and in mice. DESIGN: Prospective, controlled, dose-response, in vitro study and prospective, controlled animal study. SETTING: A university animal research laboratory. SUBJECTS: Established human lung cultured cells and male SPF ICR mice. INTERVENTIONS: Paraquat-treated (0.2 mM) A549 cells were incubated either with the antioxidative sedatives propofol (0-0.56 mM) or thiopental (0-2.0 mM), or the nonantioxidative sedatives diazepam (0-3.0 mM), midazolam (0-3.0 mM) and ketamine (0-9.0 mM), as well as the antioxidative drugs, trolox (0-2.0 mM), alpha-tocopherol (0-4.4 mM), antioxidative-processed food (AOB; 0-1.0 mg/ml), superoxide dismutase (SOD; 0 and 3,000 U/ml) and ulinastatin (0 and 50,000 U/ml), for 48 h. Paraquat-treated mice received i.v. injections of 10 mg/kg propofol, 5 mg/kg thiopental, 4.0 mg/kg trolox, 100 mg/kg alpha-tocopherol, 10 mg/kg AOB or 5,000 U/kg SOD, b.i.d. for 4 days (n = 10 each). MEASUREMENTS AND RESULTS: Post-administered propofol and thiopental, as well as the antioxidative drugs, trolox, alpha-tocopherol and AOB, improved A549 cell survival in vitro. The non-antioxidative sedatives SOD and ulinastatin were not protective. An i.p. injection of 50 mg/kg of paraquat resulted in a survival rate of 40% in mice at day 6. Propofol, trolox, alpha-tocopherol and AOB significantly lowered the mortality rate (80% survival), while thiopental did not. CONCLUSION: Post i.v. injection of propofol is protective against paraquat-induced damage. Propofol can be given during mechanical ventilatory support after paraquat poisoning.

Anesthetics, Intravenous↗
PubMed2000

Fucogalactan isolated from Sarcodon aspratus elicits release of tumor necrosis factor-alpha and nitric oxide from murine macrophages.

Eight species of mushrooms were evaluated for mitogenic activity by the tetrazolium salt 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) method using spleen cells of C3H/HeN female mice. The hot water-soluble (HWS) fraction extracted from Sarcodon aspratus showed the highest activity. The mitogen in Sa. aspratus was isolated by Sepharose 6B and DEAE-Sepharose CL-6B column chromatography. Preliminary structural analyses indicated that the mitogen was a fucogalactan. Fucogalactan elicited the release of tumor necrosis factor-alpha (TNF-alpha) and nitric oxide (NO) in macrophages of mice in vitro. TNF-alpha production induced with 50 microg/ml of fucogalactan was significantly higher than that induced by lentinan (500 microg/ml) by approximately 4.3-fold. Also, fucogalactan showed dose dependence at concentrations from 5 to 500 microg/ml in NO production. Thus, fucogalactan does elicit the release of cytokines such as TNF-alpha and NO.

Adjuvants, Immunologic↗
PubMed2000

Effects of epidural anesthesia on the cardiovascular response to a rapid increase in isoflurane concentration.

STUDY OBJECTIVE: To compare circulatory variables to an abrupt increase in isoflurance concentration via mask in patients who received either upper thoracic or lumbar epidural anesthesia, or neither. DESIGN: Prospective study. SETTING: Operating room at a university hospital. PATIENTS: 45 ASA physical status I female patients scheduled for elective surgeries with general anesthesia. INTERVENTIONS: Patients received thoracic (TEA group) or lumbar (LEA group) epidural anesthesia, or neither (control group) (n = 15 per group). An epidural catheter was inserted through the T1-T2 intervertebral space in the TEA group or L2-L3 in the LEA group, and 10 mL of 2% lidocaine without epinephrine was injected. Two minutes after induction of anesthesia with thiamylal, the inspired isoflurane concentration was rapidly increased from 0.5% to 5% and maintained for 5 minutes. MEASUREMENTS AND MAIN RESULTS: Heart rate and mean arterial pressure (MAP) were measured every minute. Mean analgesic levels obtained by epidural block were C4-T6 and T10-S1 in the TEA and LEA groups, respectively. Heart rate increased after the increase in isoflurane concentration in all groups, but increased significantly less in the TEA group than in the control or LEA groups (p < 0.05). Isoflurane also increased MAP in the control group throughout the 5-minute period, but only at the first minute of inhalation in the TEA and LEA groups. The increases in MAP in the TEA and LEA groups were significantly less than that in the control group (p < 0.05). CONCLUSION: Epidural anesthesia can blunt circulatory responses to a sudden increase in isoflurane concentration.

Adult↗
PubMed2000

Comparison of antioxidant enzyme activities between Solanum tuberosum L. Cultivars Danshaku and Kitaakari during low-temperature storage.

We compared the antioxidant enzyme activities between Solanum tuberosum L. cultivars Kitaakari and "Danshaku" during storage at 1 degrees C and 20 degrees C. The Kitaakari and Danshaku plants contained approximately 330 microM and 120 microM ascorbic acid (AsA) immediately after the harvest, respectively. At 1 degrees C, the activity of ascorbate peroxidase (APx) in the Kitaakari plants showed the tendency to increase, while in the Danshaku its activity increased temporally by 9 weeks and thereafter returned to basal levels. Superoxide dismutase (SOD) activity increased after 12 weeks in the case of the Kitaakari at 1 degrees C. Catalase did not show any difference in both cultivars at each temperature. The contents of AsA, which was one of the substrates of APx, decreased more rapidly at 1 degrees C than at 20 degrees C in both cultivars. Particularly in the case of the Danshaku, AsA contents were already less than 30 microM at 9 weeks, which confirmed that APx was inactivated.

Ascorbate Peroxidases↗
PubMed2000

Halothane attenuates the endothelial Ca2+ increase and vasorelaxation of vascular smooth muscle in the rat aorta.

Isolated spiral strips of rat thoracic aorta with endothelium were suspended for isometric tension recordings in a physiological salt solution. Endothelium-dependent vasorelaxation was elicited by carbachol 10(-6) and 10(-5) mol litre-1 during norepinephrine-induced contractions, and the effects of 1.5% and 3% halothane were evaluated with concomitant measurement of [Ca2+]i using fura-2-Ca2+ fluorescence. The effects of halothane on endothelium-dependent relaxation were compared with those of nitro G-L-arginine methyl ester 10(-4) mol litre-1 (L-NAME: an inhibitor of nitric oxide synthase). Carbachol reduced norepinephrine-induced contractions in a concentration-dependent manner, but augmented the norepinephrine-induced increase in [Ca2+]i in endothelium intact strips. In contrast, carbachol did not influence muscle tension or [Ca2+]i when the endothelium was completely denuded. Although 3% halothane and L-NAME 10(-4) mol litre-1 inhibited carbachol-induced vasorelaxation in a similar manner, halothane inhibited carbachol-induced increases in [Ca2+]i. These results indicate that halothane inhibited a carbachol-induced increase in [Ca2+]i in the endothelium, which subsequently attenuated the decrease in muscle tension.

Anesthetics, Inhalation↗
PubMed2000

Natural progression of osteochondritis dissecans of the humeral capitellum: initial observations.

PURPOSE: To determine the earliest findings, subsequent changes, and natural course of osteochondritis dissecans of the humeral capitellum. MATERIALS AND METHODS: Among 95 patients with osteochondritis dissecans of the humeral capitellum, 16 (mean age, 12.5 years) were selected for this retrospective study because they seemed to have early osteochondritis dissecans and had been followed up without any surgical treatment for 6 months or more (mean, 3.5 years). RESULTS: The initial imaging appearances of the 16 patients' lesions were divided into two types: localized subchondral bone flattening without fragments in seven, and nondisplaced fragments in nine. Patients with lesion flattening had younger ages and significantly shorter durations of symptoms, and most had open growth plates. In five of the seven with flattening, new bone formed over the flattened bone, and the fragments united after arm motion reduction. In contrast, patients with nondisplaced fragments at clinical presentation had longer durations of symptoms with continued arm motion, and their nondisplaced fragments failed to unite. CONCLUSION: The earliest feature of osteochondritis dissecans is subchondral bone flattening, over which new bone subsequently forms. The new bone then can unite with the underlying bone. However, if subjected to repetitive forces over a given time, unstable fragments develop. These fragments, even if not yet displaced, are unable to unite.

Adolescent↗
PubMed2000

Sonographic assessment of osteochondritis dissecans of the humeral capitellum.

OBJECTIVE: The purpose of this study was to determine the efficacy of sonography for revealing osteochondritis dissecans of the humeral capitellum. SUBJECTS AND METHODS: Twenty-seven patients with capitellar osteochondritis dissecans (27 males; range, 11-20 years; mean age, 14 years) underwent radiography and sonography performed with a 7.5-MHz mechanical sector probe. Lesions were assessed as stable or unstable. The sonographic assessment was compared with radiographic assessment in 27 patients, MR assessment obtained in 10, and surgical findings in 15. RESULTS: Sonographic assessment agreed with radiographic assessment in 23 of the 27 patients, MR assessment in nine of the 10, and surgical findings in 14 of the 15. Sonography revealed that two lesions, which had been underestimated on radiography, were unstable. CONCLUSION: Sonography facilitates the assessment of capitellar lesions so that treatment can be optimized.

Adolescent↗
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↗