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Biomedical subjects

Y Goda

Publications and source records attributed to Y Goda.

At least 55 records · Page 3Linked to original sources
PubMed1998

Inhibitory effects of apple polyphenol on induced histamine release from RBL-2H3 cells and rat mast cells.

The anti-allergic activities of polyphenol fractions extracted from immature fruits of apple (Rosaceae, Malus sp.) were evaluated by in vitro assays. A crude apple polyphenol (CAP) fraction, which had been obtained from the juice of immature apples by reverse-phase column chromatography, was further purified by LH-20 column chromatography to obtain an apple condensed tannin (ACT) fraction consisting of linear oligomeric epicatechins from the dimer to pentadecamer. ACT strongly inhibited the release of histamine from rat basophilic leukemia (RBL-2H3) cells stimulated by the antigen-stimulation and from rat peritoneal mast cells stimulated by compound 48/80. The IC50 values for histamine release were 30 micrograms/ml and 25 micrograms/ml, respectively. ACT also inhibited hyaluronidase activity and the increase in intracellular free calcium concentration in RBL-2H3 cells stimulated with the antigen. These results suggest that ACT affected early signal transduction including the calcium influx.

Animals↗
PubMed1997

The small GTP-binding protein Rab3A regulates a late step in synaptic vesicle fusion.

The Rab family of low-molecular-mass GTP-binding proteins are thought to guide membrane fusion between a transport vesicle and the target membrane, and to determine the specificity of docking. The docking and fusion of vesicles is, however, a complex multistep reaction, and the precise point at which Rab proteins act in these sequential processes is unknown. In brain, the Rab protein Rab3A is specific to synaptic vesicles, whose exocytosis can be monitored with submillisecond resolution by following synaptic transmission. We have now determined the precise point at which Rab3A acts in the sequence of synaptic vesicle docking and fusion by using electrophysiological analysis of neurotransmitter release in Rab3A-deficient mice. Unexpectedly, the size of the readily releasable pool of vesicles is normal, whereas Ca2+-triggered fusion is altered in the absence of Rab3A in that a more-than-usual number of exocytic events occur within a brief time after arrival of the nerve impulse.

2-Amino-5-phosphonovalerate↗
PubMed1997

Efficacy of a selective histamine H2 receptor agonist, dimaprit, in experimental models of endotoxin shock and hepatitis in mice.

Dimaprit, a selective histamine H2 receptor agonist, was examined in experimental models of endotoxin shock and hepatitis in mice. Injection of lipopolysaccharide (8 mg/kg i.v.) into Balb/c mice resulted in an elevation of plasma tumor necrosis factor-alpha (TNF-alpha), reaching the maximal level at 1 h post-lipopolysaccharide (1147 U/ml). Oral administration of dimaprit 200 mg/kg, 1 h prior to lipopolysaccharide challenge, inhibited the increase in plasma TNF-alpha by 71% and also the survival rate was increased to 62.5% from 8.3% in the disease control. In a mouse hepatitis model, simultaneous injection of galactosamine (700 mg/kg i.v.) and lipopolysaccharide (3 micrograms/kg i.v.) into Balb/c mice caused an increase in plasma TNF-alpha, peaking at 1 h, followed by an elevation of L-alanine aminotransferase (E.C.2.6.1.2) activity at 4 h onward. Oral administration of dimaprit 200 mg/kg, 1 h prior to galactosamine and lipopolysaccharide, reduced the increase in plasma TNF-alpha by 99% and L-alanine aminotransferase by 82%. In vitro, dimaprit dose dependently inhibited the production of TNF-alpha in mouse peritoneal macrophages and human peripheral blood monocytes stimulated with lipopolysaccharide with IC50 values of 1 microM. The decrease in TNF-alpha production by dimaprit was reversed by cimetidine, a histamine H2 receptor antagonist. Dimaprit dose dependently suppressed TNF-alpha mRNA in human peripheral blood monocytes. These results suggest that activation of the histamine H2 receptor downregulates the production of TNF-alpha, and that histamine may be an important regulator in pathological conditions in which TNF-alpha plays an important role.

Alanine Transaminase↗
PubMed1997

Two acylated anthocyanins from purple sweet potato.

Two new acylated anthocyanins were isolated from the storage root of Ipomoea batatas. On the basis of spectroscopic analyses, these compounds were identified as the 3-O-(6-O-trans-caffeyl-2-O-beta-glucopyranosyl-beta-glucopyranoside)-5-O - beta-glucoside of cyanidin and peonidin.

Anthocyanins↗
PubMed1997

Calcium regulation of neurotransmitter release: reliably unreliable?

Recent studies of central synaptic transmission reveal that neurotransmitter release is more unreliable than was previously thought. Nerve stimulation does not always elicit transmitter release, and when release events occur vesicle fusion with the presynaptic membrane is limited to at most a single quantum.

Animals↗
PubMed1997

[Intubation of a patient with rheumatoid arthritis with a 7.5-mm-ID armored endotracheal tube using a laryngeal mask airway].

A 71-year-old male patient with rheumatoid arthritis was scheduled for posterior fusion of the cervical spine. He showed limited cervical movement and atrophic mandible. Tracheal intubation was difficult in his last anesthetic management for the same surgery. This time, we planned a special procedure for predicted difficult tracheal intubation. After induction of general anesthesia, a size-4 laryngeal mask airway was inserted. Next, a flexible fiberscope sheathed with a 6.0-mm-ID cuffed endotracheal tube was inserted through a laryngeal mask airway into the trachea, and the fiberscope was withdrawn. Then, an endotracheal tube changer was inserted through the endotracheal tube. The laryngeal mask airway and the endotracheal tube were withdrawn simultaneously leaving the tube changer. Finally, a 7.5-mm-ID armored endotracheal tube was inserted through the tube changer. The procedure applied in this case is a safe and reliable intubating method in patients with difficult tracheal intubation.

Aged↗
PubMed1996

Long-term depression properties in a simple system.

Long-term depression (LTD) in pairs of cultured rodent hippocampal neurons was examined to study the molecular basis of this form of synaptic plasticity. We have previously characterized two components of transmitter release: a synchronous, fast phase that requires synaptotagmin I, and an asynchronous, slow component that persists in the absence of synaptotagmin I. Are these two release components differentially affected by the presynaptic changes of LTD, or is the mechanism of plasticity common to both? We find that LTD is expressed as parallel changes in the fast and slow components of release, and that this form of synaptic plasticity is still seen in the absence of functional synaptotagmin I. Any alterations in the presynaptic release machinery observed during LTD thus involve mechanisms shared by both modes of release.

Animals↗
PubMed1996

Quantitative evaluation of passive cutaneous anaphylaxis (PCA) using a hand-held spectrophotometer.

A hand-held spectrophotometer was used for the quantitative evaluation of PCA caused by anti-TNP-IgE and TNP-BSA. A good relationship existed between the dilution of sera and the value of delta E*ab (a numerical expression of color) obtained by a hand-held spectrophotometer. In addition, the value of delta E*ab and the amount of Evans blue measured by the conventional colorimetric method correlated well. Because the method using a hand-held spectrophotometer provides a simple and objective analysis, it appears that the method is suitable as a substitute for the conventional method, which is time-consuming and requires killing animals cruelly.

Animals↗
PubMed1996

Structural determination of unknown subsidiary colors in food yellow no. 5 (Sunset yellow FCF).

Major unknown subsidiary colors A (Sub A) and B (Sub B) in commercial Sunset Yellow FCF (Food Yellow No. 5 in Japan) have been isolated by preparative HPLC. Spectroscopic analyses of Sub A and Sub B revealed that their structures are trisodium salt of 6-hydroxy-7-(4-sulfophenyl)-5-(4-sulfophenylazo)-2-naphthale nesulfonic acid, and disodium salt of 3-hydroxy-4-(4-sulfophenylazo)-2-naphthalenesulfonic acid, respectively.

Azo Compounds↗
PubMed1995

FD&C Red No. 105 (Rose Bengal B) neutralizes the thyroid tumor promoting effect of iodine-deficient diet in rats.

The effect of 3,4,5,6-tetrachloro-2',4',5',7'-tetraiodo-fluorescein sodium salt (Rose Bengal B or FD&C Red No. 105, molecular weight 1017.6) on the thyroid of rats treated with N-bis(2-hydroxypropyl)-nitrosamine (DHPN) and iodine-deficient (I-def) diet is studied. Six-week-old male F344 rats were divided into seven groups (20 each) and given a single subcutaneous injection of DHPN (2800 mg/kg body wt.). From week 2 to 20, I-def diet was given in combination with either FR105 (1.25, 5.0, or 20 mg/l) or potassium iodide (KI, 12.5, 50.0 or 200 micrograms/l) in drinking water. As a result, an amount of 1.25 mg/l of FR105 was slightly more effective than 200 micrograms/l of KI in terms of inhibition of the effect of I-def diet on thyroid weight, morphology, thyroid-related hormones and thyroid tumor development. It was calculated that 1 mumol/l of FR105 was slightly more potent than 1 mumol/l of iodide ion. As each FR105 molecule has four iodide residues, at least 25% of total iodide residues were calculated to be utilized by the rats given I-def diet.

Animals↗
PubMed1995

Secondary hyperparathyroidism shortens the action of vecuronium in patients with chronic renal failure.

The authors studied the duration of action of vecuronium in 15 patients with normal renal function and 40 patients with chronic renal failure to evaluate the effect of secondary hyperparathyroidism on the action of vecuronium. The patients were divided into four groups: 15 patients with normal renal function (Group A); nine patients with chronic renal failure who did not need haemodialysis (Group B); 15 anephric patients who did not require parathyroidectomy (Group C); and 16 anephric patients who underwent parathyroidectomy because of severe secondary hyperparathyroidism (Group D). The ratio of the height of the first twitch (T1) to the baseline value before vecuronium administration was measured by an electromyogram. Baseline T1 was obtained after anaesthesia induction with thiamylal iv. The time to 10% recovery of the first twitch (REC 10) after administration of vecuronium 0.12 mg.kg-1 iv was measured in each group. Anaesthesia was maintained with isoflurane and nitrous oxide in oxygen, and supplemented with fentanyl iv. Patients in Group D showed shorter REC 10 (51 +/- 4 min) than those in Groups B (71 +/- 6 min) and C (80 +/- 10 min) (P < 0.05), but similar REC 10 to patients in Group A (37 +/- 4 min). These results suggest that the duration of action of vecuronium in anephric patients with secondary hyperparathyroidism is shorter than in those without secondary hyperparathyroidism.

Anesthesia, Inhalation↗
PubMed1995

[The duration of action of vecuronium in five patients after kidney transplantation--comparison with that during kidney transplantation].

We compared the duration of vecuronium action in five patients after the kidney transplantation with that during kidney transplantation. After the transplantation, three patients required no hemodialysis therapy but two patients underwent hemodialysis therapy again. In all these five patients, including patients who were back to hemodialysis therapy, the durations of vecuronium action after receiving transplanted kidney were shorter than those during kidney transplantation. These shortened durations are speculated to be mainly due to excretion of vecuronium by the transplanted kidney and the effect of long term steroid therapy. However in this study the durations of vecuronium action in patients who required further hemodialysis therapy were also shorter than those during kidney transplantation. To determine whether this is a common or exceptional phenomenon, further evaluation should be needed.

Adult↗
PubMed1994

Two components of transmitter release at a central synapse.

After the arrival of a presynaptic nerve impulse at an excitatory synapse in hippocampal neurons, the rate of neurotransmitter release increases rapidly and then returns to low levels with a biphasic decay. The two kinetically distinct components are differentially affected when Sr2+ is substituted for Ca2+ ions. Our findings are comparable to those of the classical studies for the frog neuromuscular junction, and thus the basic aspects of Ca(2+)-activated transmitter release machinery appear to be conserved in central synapses. The method we have used, in addition, permits us to estimate the average neurotransmitter release rate for a single bouton. The observation of differential Ca2+/Sr2+ sensitivity is consistent with a release mechanism mediated by two Ca2+ sensors with distinct Ca2+ affinities: the low-affinity Ca2+ sensor facilitates the fast synchronous phase of release, whereas the high-affinity sensor sustains the slow asynchronous phase of release.

Animals↗