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F Goto

Publications and source records attributed to F Goto.

At least 73 records · Page 4Linked to original sources
PubMed1999

Intrathecal co-administration of NMDA antagonist and NK-1 antagonist reduces MAC of isoflurane in rats.

BACKGROUND: Intravenous administration of N-methyl-D-aspartate (NMDA) receptor antagonists and alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptor antagonists reportedly reduce the minimum alveolar anaesthetic concentration (MAC) for inhalation anaesthetics. If pain perception can be prevented by the intrathecal administration of antinociceptive receptor antagonists, these agents may reduce the requirements for inhalation anaesthetics. We studied the effect of intrathecal administration of an AMPA/kainate receptor antagonist, a metabotropic glutamate (mGlu) receptor antagonist and co-administration of NMDA and a neurokinin-1(NK-1) receptor antagonist drugs at low doses on the MAC. METHODS: After Wistar rats (n=36) were fitted with indwelling intrathecal catheters, the MAC of isoflurane was determined following intrathecal administration of a non-NMDA receptor antagonist (CNQX) at 10 microg, a mGlu receptor antagonist (AP3) at 10 microg, or a combination of NMDA receptor antagonist (APV) at 0.01 microg to 1 microg with NK-1 receptor antagonist (CP96345, CP) at 0.1 microg to 10 microg. Subsequently, a reversal dose of intrathecal NMDA with substance P (SP) was administered, and the MAC of isoflurane was redetermined. Conscious rats (n=15) were also examined for the presence of locomotor dysfunction following the intrathecal co-administration of APV and CP. RESULTS: Neither CNQX nor AP3 reduced the MAC of isoflurane. APV at 0.01 microg plus CP at 1 microg, as well as APV at 0.1 microg plus CP at 10 microg, reduced the MAC of isoflurane, with respective reductions of 7.6% and 14%; (P<0.05). Co-administration of NMDA plus SP reversed the decrease in the MAC of isoflurane. Locomotive activity was not changed. CONCLUSIONS: The NMDA receptor and the NK-1 receptor are important determinants of the MAC of isoflurane, exerting this influence by inhibition of pain transmission in the spinal cord, while mGlu and AMPA receptors have no effect on the MAC of isoflurane.

6-Cyano-7-nitroquinoxaline-2,3-dione↗
PubMed1999

Iron fortification of rice seed by the soybean ferritin gene.

To improve the iron content of rice, we have transferred the entire coding sequence of the soybean ferritin gene into Oryza sativa (L. cv. Kita-ake) by Agrobacterium-mediated transformation. The rice seed-storage protein glutelin promoter, GluB-1, was used to drive expression of the soybean gene specifically in developing, self-pollinated seeds (T1 seeds) of transgenic plants, as confirmed by reverse transcription PCR analysis. Stable accumulation of the ferritin subunit in the rice seed was demonstrated by western blot analysis, and its specific accumulation in the endosperm by immunologic tissue printing. The iron content of T1 seeds was as much as threefold greater than that of their untransformed counterparts.

Blotting, Southern↗
PubMed1999

The effect of intrathecal magnesium sulphate on nociception in rat acute pain models.

We examined the antinociceptive effect of intrathecally administered magnesium sulphate (MgSO4) in rats, using acute pain models including mechanical pressure, heat and subcutaneous formalin injection. According to the locomotion test 10 microliters of 6.2% MgSO4 did not produce motor paralysis. At the same dose, responses to pressure and heat were intact, compared with controls given saline. MgSO4 produced depression of pain responses only after the first 10 min in the formalin test. Our studies indicated that MgSO4 did not show remarkable antinociceptive effects in acute pain models.

Acute Disease↗
PubMed1999

Substrate specificity studies of Flavobacterium chondroitinase C and heparitinases towards the glycosaminoglycan--protein linkage region. Use of a sensitive analytical method developed by chromophore-labeling of linkage glycoserines using dimethylaminoazobenzenesulfonyl chloride.

Bacterial chondroitinases and heparitinases are potentially useful tools for structural studies of chondroitin sulfate and heparin/heparan sulfate. Substrate specificities of Flavobacterium chondroitinase C, as well as heparitinases I and II, towards the glycosaminoglycan-protein linkage region -HexA-HexNAc-GlcA-Gal-Gal-Xyl-Ser (where HexA represents glucuronic acid or iduronic acid and HexNAc represents N-acetylgalactosamine or N-acetylglucosamine) were investigated using various structurally defined oligosaccharides or oligosaccharide-serines derived from the linkage region. In the case of oligosaccharide-serines, they were labeled with a chromophore dimethylaminoazobenzenesulfonyl chloride (DABS-Cl), which stably reacted with the amino group of the serine residue and rendered high absorbance for microanalysis. Chondroitinase C cleaved the GalNAc bond of the pentasaccharides or hexasaccharides derived from the linkage region of chondroitin sulfate chains and tolerated sulfation of the C-4 or C-6 of the GalNAc residue and C-6 of the Gal residues, as well as 2-O-phosphorylation of the Xyl residue. In contrast, it did not act on the GalNAc-GlcA linkage when attached to a 4-O-sulfated Gal residue. Heparitinase I cleaved the innermost glucosaminidic bond of the linkage region oligosaccharide-serines of heparin/heparan sulfate irrespective of substitution by uronic acid, whereas heparitinase II acted only on the glucosaminidic linkages of the repeating disaccharide region, but not on the innermost glucosaminidic linkage. These defined specificities of chondroitinase C, as well as heparitinases I and II, will be useful for preparation and structural analysis of the linkage oligosaccharides.

Bacterial Proteins↗
PubMed1999

Identification and characterization of a novel UDP-GalNAc:GlcAbeta-R alpha1,4-N-acetylgalactosaminyltransferase from a human sarcoma cell line.

We recently discovered a novel alpha-N-acetylgalactosaminyltransferase in fetal bovine serum (Kitagawa et al., J. Biol. Chem., 270, 22190-22195, 1995) and also in mouse mast cytoma cells (Lidholt et al., Glycoconjugate J., 14, 737-742, 1997), which catalyzed the transfer of an alpha-GalNAc residue to the linkage tetrasaccharide-serine, GlcAbeta1-3Galbeta1-3Galbeta1-4Xylbeta1-O-Ser, derived from proteoglycans. In this study, we characterized this enzyme using a preparation obtained from the serum-free culture medium of a human sarcoma (malignant fibrous histiocytoma) cell line by phenyl-Sepharose chromatography. Structural characterization by1H NMR spectroscopy of the reaction product using the linkage tetrasaccharide-serine, GlcAbeta1-3Galbeta1-3Galbeta1-4Xylbeta1-O-Ser, as a substrate demonstrated that the enzyme was a UDP-GalNAc:GlcAbeta1-R alpha1,4-N -acetylgalactosaminyltransferase. This is the first identification of an alpha1,4-N-acetylgalactosaminyltransferase. Using N -acetylchondrosine GlcAbeta1-3GalNAc as an alternative substrate, the enzyme required divalent cations for the transferase reaction, with maximal activity at 20 mM Mn2+and exhibited a dual optimum at pH 6.5 and pH 7.4 depending upon the buffers used, with the highest activity in a 50 mM 2-( N -morpholino)ethanesulfonic acid buffer at pH 6.5. The apparent Km values obtained for N -acetylchondrosine, the linkage tetrasaccharide-serine, and UDP-GalNAc were 1060 microM, 188 microM, and 27 microM, respectively. This suggested that the linkage tetrasaccharide-serine was a good acceptor substrate for the enzyme. In addition, the enzyme utilized glucuronylneolactotetraosylceramide GlcAbeta1-3Galbeta1-4GlcNAcbeta1-3Galbeta1-4G lcbeta1-1Cer but not sulfoglucuronylneolactotetraosylceramide GlcA(3-O -sulfate)beta1-3Galbeta1-4GlcNAcbeta1-3Galbeta1-4Gl cbeta1-1Cer as acceptor substrates. The possibility of involvement of this enzyme in the biosynthesis of glycosaminoglycan as well as other GlcA-containing glycoconjugates is discussed.

Animals↗
PubMed1999

Cecal ligation and puncture peritonitis model shows decreased nicotinic acetylcholine receptor numbers in rat muscle: immunopathologic mechanisms?

BACKGROUND: Although systemic inflammation is believed to cause upregulation of nicotinic acetylcholine receptors (nAchRs) in muscle, chronic infections such as Chagas' disease occasionally are complicated by myasthenia gravis. The authors investigated how a nonlethal cecal ligation and puncture (CLP) peritonitis model in rats could affect muscle nAchR. METHODS: On day 1, 4, 7, 14, or 21 after CLP or sham operation, nAchR binding was assayed in the anterior tibial muscle and diaphragm using [125I]alpha-bungarotoxin. The presence or absence of weakness, in vivo dose-response relationships for d-tubocurarine, and serum anti-nAchR antibody titers were assayed in separate experiments. RESULTS: Systemic inflammation was most severe during the first 4 to 5 days. Numbers of nAchRs were decreased in anterior tibial muscle on days 7, 14, and 21 after CLP, and in the diaphragm on days 7 and 14 (P < 0.01). Both 50% and 90% blocking doses of d-tubocurarine) were lower in CLP rats than in sham-operated rats on days 7, 14, and 21 (P < .05). Weakness was overt in approximately half of CLP rats at these times. Serum anti-nAchR antibody (0.7-1.4 nM) was detectable beginning on day 4 and continuing throughout the 21-day observation period in 58-67% of CLP rats. CONCLUSIONS: During the recovery phase of injury, nonlethal CLP peritonitis resulted in downregulation of nAchR. However, further study is needed to determine the role of anti-nAchR antibodies in the development of decreased receptor numbers and impaired neuromuscular function.

Animals↗
PubMed1999

Comparison of the hemodynamic effects of amrinone in patients who required low-to-moderate-dose and high-dose catecholamines after cardiac valve replacement.

OBJECTIVES: To determine hemodynamic response to amrinone in patients after cardiac surgery, in relation to the postoperative cardiac function, which was indicated by the required doses of catecholamines. DESIGN: Prospective clinical study. SETTING: Surgical intensive care unit in a university hospital. PATIENTS: Fourteen patients who required a low-to-moderate dose of dopamine and dobutamine (group L) and 14 patients who required a high dose of dopamine and dobutamine (group H) after cardiac valve replacement. INTERVENTIONS: A loading dose of amrinone (0.75 mg/kg) was administered during a 15-min period and the continuous infusion was followed incrementally by doses of 5, 10, and 20 microg/kg/min every 60 mins on the first postoperative day. MEASUREMENTS AND MAIN RESULTS: Hemodynamic variables were determined by the radial and pulmonary artery catheters at a dose of 0, 5, 10, and 20 microg/kg/min. Two-way repeated-measures analysis of variance showed significant interaction in the two groups in cardiac index and mean systemic arterial pressure. Cardiac index increased in a dose-dependent manner in group L but was unchanged in group H. Systemic vascular resistance index decreased in a dose-dependent manner in both groups. The mean systemic arterial pressure decreased in group L at a dose of 5 microg/kg/min and returned to the baseline level at doses of 10 and 20 microg/kg/min. On the other hand, the mean systemic arterial pressure significantly decreased in group H at a dose of 20 microg/kg/min. CONCLUSIONS: The inotropic effects of amrinone after cardiac valve replacement may be associated with the postoperative myocardial reserve, which was indicated by the required doses of catecholamines, although a similar vasodilative effect was observed in both groups.

Adult↗
PubMed1999

[The effect of propofol as an anticonvulsant].

We observed that propofol was very effective for the refractory general convulsion after surgical operation of cerebral aneurysmal clipping in two patients. The first patient had suffered from asthma. Standard regimens except for thiopental were ineffective for the refractory general convulsion after the operation. So, we administered propofol to the patient, at the dosage of 1 mg.kg-1 intravenously and then, 1 mg.kg-1.hr-1 continuously i.v. Propofol suppressed the general convulsions completely. On the EEG, there were no convulsive spikes. Furthermore, patient's consciousness became clearer during the administration of propofol. The convulsion in the second patient not suffering from asthma, was intractable, too and diazepam, phenytoin, and phenobalbital were not effective. Then, we tried propofol in the same way, and good effect was obtained. Propofol may be an effective medicine for the refractory general convulsion.

Anticonvulsants↗
PubMed1998

Platelet-activating factor receptor antagonist attenuates endotoxin-induced vascular hyporeactivity in the pithed rat.

The role of platelet activating factor (PAF) and nitric oxide (NO) in the endotoxin-induced hyporeactivity to noradrenaline was studied in the pithed rat. Pressor dose-response curves to noradrenaline (0.01-10 microg/kg, i.v.) were made starting 1 h after the administration of endotoxin (0.5 mg/kg, i.v.) to the rats. Saline was administered to the control rats. The PAF receptor antagonist, TCV-309 (3-bromo-5-[N-phenyl-N-[2-[[2-(1,2,3,4-tetrahydro-2-isoquinolylcarbon yloxy)ethyl]carbamoyl]ethy]carbamoyl]-1-propylpyridinium nitrate, 100 microg/kg, i.v.), or the NO synthase inhibitor, N(G)-monomethyl-L-arginine (L-NMMA, 30 mg/kg, i.v.), was administered to the endotoxin-treated rats 20 or 10 min before the noradrenaline challenge. L-NMMA reversed endotoxin-induced hyporeactivity completely. TCV-309 produced a significant, but partial attenuation of the hyporeactivity to noradrenaline (P < 0.01). There was still significant hyporeactivity when compared with the control rats (P < 0.01) and the L-NMMA-treated endotoxin-administered rats (P < 0.05). These data suggest that endogenous PAF contributes to the vascular hyporeactivity to noradrenaline induced by endotoxin and that NO plays a major role in the endotoxin-induced hyporeactivity.

Animals↗
PubMed1998

Viscosity of diluent and sensory level of subarachnoid anaesthesia achieved with tetracaine.

PURPOSE: Our objective was to evaluate the effect of viscosity in determining the cephalad spread of tetracaine administered by the subarachnoid route. METHODS: We studied 42 patients that were randomly assigned to receive subarachnoid anaesthesia for arthroscope of the knee. They received 8 mg tetracaine dissolved in either glucose 10%, sodium chloride (NaCl) 5%, glucose 5%, or NaCl 2.5%. The specific gravity and viscosity of each solvent was also measured. Cephalad spread was defined as the level of sensory block achieved. RESULTS: The specific gravity of the glucose 5% and the NaCl 2.5% solutions were similar (1.0197 +/- 0.0001 vs 1.0177 +/- 0.0001 (mean +/- SD)). That was also true for the more concentrated pair of solutions (1.0385 +/- 0.0001 for glucose 10% vs 1.0353 +/- 0.0003 in NaCl 5%). However, the viscosities of the 10% and 5% solutions of glucose (0.01178 +/- 0.0002 and 0.01020 +/- 0.0002 (g.cm-1.sec-1)) were higher (P < 0.05) than that of the other two solutions, being 0.00955 +/- 0.0001 for NaCl 5% and 0.00934 +/- 0.0002 for NaCl 2.5%. The median maximal extent of sensory block achieved was significantly higher (P < 0.05) with a solution of tetracaine in glucose 10% injected into the subarachnoid space at the L3-4 interspace than that observed in the two groups administered tetracaine in NaCl. The level of sensory block 30 min after the injection of anaesthetic was; T3 [T1-6] (median [range]) with glucose 10%, T6 [T4-10] with NaCl 5%, T5 [T2-11] with glucose 5%, and T5.5 [T2-11] with NaCl 2.5%. CONCLUSION: Viscosity was shown to be one of determinants of the clinical extent of spread of a subarachnoid anaesthetic such as tetracaine.

Adolescent↗
PubMed1998

Anaesthesia affects outcome of sepsis in mice.

PURPOSE: To determine whether the survival curves and rates differ between a mutant strain of mice (C3H/HeJ: endotoxin-resistant) and an endotoxin-susceptible strain (C3H/HeN) when severe sepsis (caecal ligation and puncture: CLP) is performed with different anaesthetics (ketamine or varied exposure to halothane). METHODS: The CLP was performed under a randomly chosen anaesthetic method out of inhalation of halothane in oxygen (15 min, 2 hr, or 6 hr) (100, 120, and 103 mice respectively) or a single injection of ketamine im (127 mice) in paired fashion in eight-week-old male mice of each strain. The daily survival rates were compared between the two strains until the 10th day after CLP for each anaesthetic and among the four anaesthetic methods for each strain using multiple comparisons. RESULTS: The C3H/HeJ had delayed death relative to the C3H/HeN with every anaesthetic method except a two hours halothane (P < 0.01 at day 1 and day 2-5 in halothane 15 min and 6 hr, P < 0.05 at day 4-6 in ketamine), however, the final survival rates for each method of anaesthesia were the same in the two strains. Regardless of the genetic susceptibility to endotoxin, short exposure to halothane resulted in the most rapid death compared with the other anaesthetic methods (P < 0.05), and two hours halothane showed the best survival. CONCLUSION: Endotoxin susceptibility affected the septic course for each anaesthetic method, and the anaesthetic methods influenced the survival from sepsis in both strains.

Anesthesia↗
PubMed1998

Cerebral oxygenation during prostaglandin E1 induced hypotension.

PURPOSE: To evaluate the cerebral oxygenation effects of hypotension induced by prostaglandin E1 (PGE1) during fentanyl-oxygen anaesthesia. METHODS: Ten patients who underwent elective cardiac surgery received infusion of PGE1. After measuring the baseline arterial, mixed venous and internal jugular vein blood gases, systemic haemodynamics, and regional cerebral oxygen saturation (rSO2) estimated by INVOS 3100R, PGE1 was continuously infused at 0.25-0.65 microgram.kg-1.min-1 (mean dosage: 410 +/- 41.4 mg.kg-1.min-1) intravenously. Ten, 20 and 30 minutes after the start of drug infusions, blood gases described above were obtained simultaneously with the measurement of systemic haemodynamics and rSO2. Thirty minutes from the start of drug infusions, administration of PGE1 was stopped. The same parameters were measured again 10, 30 minutes after the stop of drug infusion. RESULTS: PGE1 decreased mean arterial pressure (MAP) to approximately 70% of the baseline value (P < 0.05). PGE1 increased mixed venous saturation, but in contrast did not affect internal jugular pressure, internal jugular oxygen saturation and rSO2. CONCLUSIONS: These results suggest that PGE1 is a suitable drug for induced hypotension because flow/metabolism coupling of brain and regional cerebral oxygenation were well maintained during hypotension.

Alprostadil↗
PubMed1998

Vecuronium dose requirement and pupillary response in a patient with olivopontocerebellar atrophy (OPCA).

PURPOSE: Olivopontocerebellar atrophy (OPCA), a variant of spinocerebellar degeneration (Shy-Drager syndrome), is a systemic degenerative disorder affecting the neurons of multiple nuclei. We investigated the sensitivity to vecuronium and the pupillary responses to various stresses in a patient with OPCA. CLINICAL FEATURES: A 65-yr-old woman with a six-month history of OPCA underwent a left upper lobectomy for lung cancer under propofol-N2O anaesthesia. She had symptoms of dysarthria, bulbar palsy, cerebellar ataxia, Parkinsonism, myosis, pyramidal signs and muscular atrophy of the distal extremities. A cumulative dose-response curve for vecuronium was constructed, and pupillary changes in response to various noxious stimuli were evaluated with concomitant recording of the Spectral-Edge-Frequency 90% (SEF90; the frequency below which 90 percent of the EEG power is located). The dose-response curve for vecuronium and the estimated ED50 value (the 50% blocking dose of vecuronium) in this patient with OPCA were almost identical with those of five ASA I-II patients (27 micrograms.kg-1 vs 31 micrograms.kg-1). The pupil size and the SEF90 did not change after tracheal intubation or surgical stimulation in this patient, while in the control subjects (n = 3), these measures increased in response to both stresses. CONCLUSIONS: The absence of pupillary and SEF90 responses to noxious stimuli suggests a sensitivity to propofol and/or central autonomic dysfunction in patients with OPCA. Although the dose requirement of vecuronium in this patient was similar to that of the control patients, the effects of neuromuscular blockers may vary depending on the severity of muscle atrophy.

Aged↗
PubMed1998

Measurement of blood concentration of indocyanine green by pulse dye densitometry--comparison with the conventional spectrophotometric method.

OBJECTIVE: Pulse dye densitometry (PDD) uses two wavelengths (805 and 890 nm) in association with pulse oximetry to compute the arterial blood concentration ratio of indocyanine green (ICG) to hemoglobin (Hb). When Hb is measured in the usual way, this permits the PDD to compute cardiac output, plasma or blood volume, and liver blood flow following an intravenous injection of ICG. In this study, we evaluate the accuracy of the PDD calculation of dye concentration by comparing it with measurement of the dye concentration in blood (Cb) measured by the spectrophotometric cuvette method during dye clearance in patients. METHODS: In 25 patients receiving major abdominal surgery, ICG (10, 20, or 40 mg) was injected into a central vein and arterial ICG concentration was continuously and simultaneously monitored at nose and finger by PDD; concurrently, ICG concentrations were measured by a spectrophotometer at 805 nm in 4 radial arterial blood samples. Repeated measures or one-way ANOVA were used for comparison of ICG concentrations and percent errors by PDD at the nose, finger, and Cb. RESULTS: The percent error (bias) of calculated dye concentration and its standard deviation (precision) was -3.9 +/- 16.8% (p < 0.01) with the probe on a nostril and 3.4 +/- 12.6% using the finger probe. These errors were found to be greatest when the mean transit time of the dye was rapid (-20.7 +/- 6.8% at nose p < 0.01 and -8.5 +/- 2.5% at finger p < 0.05) due to factors other than the time delay of blood sampling. CONCLUSION: These errors are of similar size to those associated with thermal cardiac output measurement, suggesting that PDD should be valuable clinically as a noninvasive tool especially since it provides values for blood volume and liver blood flow.

Aged↗
PubMed1998

The effect of intrathecal administration of magnesium sulphate in rats.

Somatosensory evoked potential, locomotion and vocalisation upon tail pinch in rats was studied in order to determine whether intrathecal magnesium sulphate administration causes spinal anaesthesia. In Wistar rats with indwelling intrathecal catheters, cortical somatosensory evoked potential was recorded following stimulation via electrodes inserted into the hind paw under chloral hydrate anaesthesia before and after intrathecal administration of 10 microliters of either magnesium sulphate (12.3% or 24.6%) or lignocaine (4% or 8%). Locomotion and vocalisation after tail pinch were tested following intrathecal administration of the same two drugs in conscious rats. Somatosensory evoked potential amplitude was diminished after administration of lignocaine (p < 0.05) but did not change after magnesium sulphate. Latency of P1 was increased by lignocaine and by magnesium sulphate 12.3% (p < 0.05). Although lower extremity paralysis was observed in both groups, its duration with magnesium sulphate was much longer than with lignocaine. Vocalisation was recognised after magnesium sulphate 12.3%, but was not observed after lignocaine 8% during paralysis (p < 0.05). We believe that magnesium sulphate caused motor paralysis, but not complete analgesia.

Anesthesia, Spinal↗
PubMed1998

Intraoperative QRS-interval changes caused by hyperkalaemia in an infant with Arima syndrome.

A one-year-and-ten-months-old male infant with Arima syndrome, a very rare genetic disorder, underwent urgent insertion of a catheter for continuous ambulatory peritoneal dialysis (CAPD) under general anaesthesia. During the procedure he showed QRS-interval changes caused by hyperkalaemia which was successfully treated with calcium gluconate. The management and intraoperative complications of this syndrome are reported and available literature reviewed.

Abnormalities, Multiple↗
PubMed1998

High predictive value of red cell volume measurement using carboxy-haemoglobin in a rabbit model of haemorrhage.

We have studied the accuracy of blood volume measurements using carbon monoxide (CO)-labelled haemoglobin (COHb) injection and dilution (CO method) by comparing changes in red cell volume (RCV) measured using the CO method and 51Cr-labelled erythrocyte dilution (51Cr method) in a haemorrhage and infusion model in rabbits. RCV was measured repeatedly using the CO method at four different blood volume stages (stages I-IV). At stages I and IV, RCV was measured simultaneously using the 51Cr method. In comparing the sum of the circulating RCV and extracted RCV (SUM RCV) using the CO method, the values were almost equal and there were no significant differences between the values at the four stages. In comparing circulating RCV measured using the CO method and the 51Cr method, mean difference between the two methods was 0.80 (SD 0.76) ml kg-1 or 4.7 (4.6)%, and a positive correlation was observed (r = 0.91). We conclude that the CO method can be used to measure blood volume during perioperative periods in infants because it avoids use of a radioactive tracer, is simple and repeated measurements are possible.

Animals↗