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T Kondoh

Publications and source records attributed to T Kondoh.

At least 181 records · Page 10Linked to original sources
PubMed1991

[Significance of umbilical plasma concentrations of catecholamines and their metabolites in patients with term vaginal deliveries].

In an attempt to further clarify the physiological significance of Catecholamine (CA) s in the feto-placental unit, umbilical plasma concentrations of CAs and CA metabolites, 3-methoxy-4-hydroxy-phenylglycol (MHPG), 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) were measured in cases of full-term vaginal deliveries by HPLC-ECD. Results were as follows. 1. Norepinephrine (NE) and epinephrine (E) levels were significantly higher in arterial than in venous plasma, but no significant arterio-venous differences were found with dopamine (DA) concentrations. 2. High concentrations of MHPG, DOPAC and HVA were demonstrated in both arterial and venous plasma. 3. DOPAC and HVA levels were significantly higher in arterial than in venous plasma, but no significant arterio-venous differences were noted with MHPG. 4. A significant positive linear relations hip was demonstrated between arterial levels of NE and MHPG as well as DA and DOPAC, DA and HVA. 5. Arterial plasma MHPG levels were correlated significantly with arterial plasma pH and pO2. These results suggest that, in the feto-placental unit, NE, E and DA turnover is increased at term vaginal deliveries, and NE and E secretion sensitively responds to fetal respiratory and metabolic states. In addition, it is suggested that the mechanism which controls the DA turnover is different from that of NE and E.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1991

Noncontractile acetylcholine receptor-operated Ca++ mobilization: suppression of activation by open channel blockers and acceleration of desensitization by closed channel blockers in mouse diaphragm muscle.

The effects of various blockers of the nicotinic acetylcholine receptor-activated ionic channel on noncontractile slow Ca++ mobilization were investigated at the neuromuscular synapse of aequorin-injected diaphragm muscles of mice. Intracellular Ca++ mobilization (Ca++ transients) was evoked in the presence of neostigmine (0.3 microM) by nerve stimulation. Bupivacaine, an open channel blocker, decreased the peak amplitude, whereas chlorpromazine, a closed channel blocker, shortened the duration. Phencyclidine, an open and closed channel blocker, decreased both peak amplitude and duration. beta-Eudesmol, a compound of Atractylodes lancea, clearly and specifically shortened the duration but had little effect on peak amplitude. All the above channel blockers, when given in the same concentration ranges, also blocked the total amount of contractile Ca++ transients. The effects of bupivacaine, chlorpromazine and phencyclidine on noncontractile Ca++ transients were not affected by 5 mM [Ca++]o, whereas the effect of beta-eudesmol was enhanced. Geographutoxin II (0.3 microM), a skeletal muscle Na+ channel blocker, selectively and partly reversibly blocked contractile Ca++ transients without affecting noncontractile ones. These results suggest that: 1) the activation of noncontractile Ca++ mobilization is suppressed by open channel blockers, whereas its desensitization is accelerated by closed channel blockers and 2) activation of the muscle Na+ channel and subsequent release of Ca++ from sarcoplasmic reticulum is not involved in the mechanism of noncontractile Ca++ mobilization. It may reflect the steps of the desensitization process.

Aequorin↗
PubMed1991

Enhancing effect by nicotinic acetylcholine receptor channel blockers, including beta-eudesmol, on succinylcholine-induced inhibition of twitch tension and intracellular Ca++ in mouse diaphragm muscle.

To elucidate the mechanism of neuromuscular block by succinylcholine, nerve-evoked changes in intracellular Ca(++)-aequorin luminescence and twitch tension were measured simultaneously in the presence of several different types of blockers for the nicotinic acetylcholine receptor channel. Mouse diaphragm muscles were pretreated for 30 to 60 min with 3 to 40 microM bupivacaine, chlorpromazine, phencyclidine and beta-eudesmol. The effects of these noncompetitive blockers on the succinylcholine-induced response were also compared with those for pancuronium. These channel blockers potentiated (2- to 10-fold) both the blocking effects on intracellular Ca++ and twitch tension of succinylcholine (13-100 microM), but not the pancuronium (0.3-1.1 microM)-induced block. These channel blockers also suppressed succinylcholine (1.3-5 microM)-induced enhancement of evoked Ca++ transients. On the other hand, the channel blockers inhibited the succinylcholine (2.5-100 microM)-induced increase in basal Ca++ transients. These results suggest that neuromuscular block induced by succinylcholine is mainly due to desensitization of the nicotinic acetylcholine receptor.

Aequorin↗
PubMed1990

Quantitative analysis of glutathione in rat central nervous system: comparison of GSH in infant brain with that in adult brain.

Reduced glutathione (GSH) plays an important role in cellular protection against damage from free radicals and other electrophiles. GSH in the rat central nervous system was quantitatively analyzed. In adult brain, tissue from the cerebellum and cerebrum had higher GSH levels than that from the brainstem and spinal cord. Infant cerebrum and cerebellum contained lower levels of GSH than adult cerebrum and cerebellum. These data seem to suggest that the brainstem and spinal cord in adults, and the cerebrum and cerebellum in infants, are more vulnerable to injury by free radical-like radiation than the cerebrum and cerebellum in adults.

Aging↗
PubMed1990

Postsynaptic nicotinic ACh receptor-operated Ca2+ transients with neostigmine in phrenic nerve-diaphragm muscles of mice.

The second phase of Ca2+ transients (aequorin luminescence) which was not accompanied by twitch tensions were generated by 0.3 microM neostigmine in indirectly-stimulated diaphragm muscles of mice. This phase was dependent on external [Ca2+]o, was inhibited by a low concentration of (+)-tubocurarine (+)-TC; 0.013-0.13 microM) or pancuronium (Panc; 0.034-0.14 microM), and was not inhibited by atropine (3 microM) or nitrendipine (10 microM). These results suggest that nicotinic acetylcholine receptor highly sensitive to (+)-TC may stimulate Ca2+ influx through receptor-operated Ca2+ channels.

Animals↗
PubMed1990

Changes in intracellular Ca2+ produced in the mouse diaphragm by neuromuscular blocking drugs.

Differences between the effects of depolarizing and competitive neuromuscular blocking drugs on Ca2(+)-aequorin luminescences (Ca2+ transients) emitted during twitches were compared in indirectly-stimulated diaphragm muscles of mice. Succinylcholine enhanced intracellular Ca2+ transients at concentrations of 1.3-2.5 microM and inhibited them at concentrations of 5.0-50 microM, demonstrating a biphasic response as in the case of twitch tensions. However, the response to Ca2+ transients was two to three times more sensitive than the response to twitch tension. Decamethonium 2.4-96 microM and carbachol 5.5-109 microM produced similar results. In contrast, pancuronium and (+)-tubocurarine inhibited them in the same concentration ranges. The relation between Ca2+ transients and twitch tensions was hyperbolic and was computer-simulated by the Hill equation in the case of succinylcholine, decamethonium and carbachol, whereas it was represented by a single exponential equation in the case of pancuronium, (+)-tubocurarine, and submaximal nerve-stimulation voltage. Spontaneous Ca2+ transients, on the other hand, were generated only in response to depolarizing drugs at concentrations having a neuromuscular blocking effect. These results suggest that depolarizing and competitive neuromuscular blocking drugs affect intracellular Ca2+ mobilization by different routes mediated by acetylcholine receptors.

Aequorin↗
PubMed1990

Surgical approaches to foramen magnum meningioma--report of three cases.

Although foramen magnum meningiomas are usually removable, their location poses considerable surgical risk. The authors present three cases of foramen magnum meningioma. The first involved a ventral type tumor extending to the second cervical body. Following bilateral mandibulotomy, surgery was performed via the anterior transoral approach and the tumor was totally removed. Nine days postoperatively, she developed meningitis, which was successfully treated with antibiotics. The second patient's tumor was dorsal type and was deeply embedded in the lateral part of the vermis. The tumor was totally removed via the midline suboccipital approach and she recovered uneventfully, with only slight upper-extremity paresthesia. In the third case, the tumor was ventral type and situated mainly in the clivus. Craniotomy was performed by the bilateral suboccipital approach and extended nearly to the jugular tubercle. The tumor, which severely displaced the lower cranial and upper cervical nerves, was totally removed. The postoperative course was lengthy and complicated. Artificial ventilation was required for 2 months, and difficulty in swallowing persisted during long-term follow-up. As illustrated by the second case, dorsal and lateral type foramen magnum meningiomas can usually be removed via the lateral suboccipital approach. In the case of ventral type tumors, the anterior transoral approach entails the risk of infection, as occurred in the first case. The authors conclude that the lateral suboccipital approach is preferable; craniotomy extending to the jugular tubercle lowers the risk of brainstem damage.

Adult↗
PubMed1989

Micro extraction of DNA from whole blood and amniocytes.

We describe methods for extracting genomic DNA from a small amount of whole blood or cultured amniocytes. Nuclear DNA was extracted from whole blood spotted on blotting paper. Relatively large molecules of DNA with the average amount of 7-9 micrograms was extracted from 1 ml of blood spotted and stored for at most two years, being roughly 1/3 of that extracted directly from fresh whole blood. The estimated minimum amount of whole blood that gives a suitable autoradiogram of Southern hybridization was 0.3 ml. Another series of amounts of whole blood or an amniocyte suspension were molded in low-melting agarose into an 100 microliter gel block. The DNA extracted from a block that was made from at least 0.25 ml of whole blood, or from 1.25 x 10(5) amniocytes (equivalent to 1/8 of the number of confluent cells in a 25 cm2 culture flask) resulted in one suitable Southern analysis. Both methods described here are applicable to the diagnosis of newborns and/or fetuses at risk of a genetic disease and to the diagnosis of a patient from whom a large amount of blood material is difficult to obtain. These methods also make a long-way transportation of the materials possible.

Adult↗
PubMed1989

Satellited chromosome 9 in a boy with multiple anomalies.

A 5-year-old boy with multiple congenital anomalies showed a satellited long-arm chromosome 9, a previously undescribed abnormality. Various banding analyses of his chromosomes and those of his parents indicated that a reciprocal translocation, t(9;22)(q34.3;q11.21), occurred in the father's gonad, and one of the translocation chromosomes was then transmitted to the patient. Thus, the patient's karyotype was interpreted as 46,XY,-9,+psudic(9),t(9;22)(q34.3;q11.21). He showed several features similar to those of the Williams syndrome. The gene(s) responsible for the syndrome thus could be at either 9q34.3-qter or 22pter-q11.2. Southern blot analysis of the patient's DNA indicated the presence of two copies of the argininosuccinate synthetase gene which had been assigned to 9q34.1-qter. In view of the fact that the 9q34.3-qter segment is monosomic in the patient, the gene locus was deduced to be at 9q34.1-q34.2 segment.

Abnormalities, Multiple↗
PubMed1989

Contralateral trigeminal neuralgia as a false localizing sign in calcified chronic subdural hematoma: a case report.

A case of trigeminal neuralgia caused by a contralateral calcified chronic subdural hematoma is reported. Preoperative magnetic resonance imaging revealed rotational displacement of the pons caused by huge chronic subdural hematoma. The neuralgia was completely alleviated after removal of the hematoma. The clinical and radiological features are described, and the possible mechanism of the neuralgia is briefly discussed.

Calcinosis↗
PubMed1989

Effects of tetrodotoxin on relaxation of pig duodenal circular muscle induced by C-terminal fragments of cholecystokinin.

1. The mechanisms by which cholecystokinin (CCK)-C-terminal peptides relax the isolated duodenal circular muscles of pigs were compared with mechanisms involving high potassium and electrical stimulation. 2. The relaxation (30%) induced by CCK-8 0.263 nM was completely and non-competitively blocked by tetrodotoxin (TTX) 0.313 microM, and was enhanced 2-2.5 times by mesaconitine 0.158 microM, tetraethylammonium (TEA) 0.597 mM and ouabain 0.136 microM. 3. The TTX sensitivity was greater for CCK-8 and CCK-6, than for CCK-5 and CCK-4. 4. High potassium (11.8-23.6 mM)-induced, or electrically stimulated (0.3-30 Hz) relaxation showed similar characteristics except that they were not antagonized by the CCK antagonist P3-I (168 microM). 5. Apamin (0.385-3.85 microM) enhanced relaxation induced by 10.6 mM K+, but did not affect relaxation induced by CCK-8. 6. These results indicate that: (1) CCK-8, K+, and transmural electrical stimulation relax duodenal circular muscles by releasing an endogenous inhibitory substance; (2) the latter two do not mediate the release of CCK; and (3) the mechanisms for relaxation by CCK-4 are different from those of CCK-8.

Animals↗
PubMed1989

[Extracranial-intracranial arterial bypass in the management of symptomatic vasospasm].

Delayed neurologic deterioration from vasospasm remains the greatest cause of morbidity and mortality following subarachnoid hemorrhage. The authors performed superficial temporal artery-middle cerebral artery bypass in three patients with symptomatic vasospasm and studied its effects on cerebral hemodynamics. All three patients responded neurologically to the bypass procedure within 24 hours. The average cerebral blood flow in the region supplied by the spastic middle cerebral artery increased from 40 ml/100 g/min to 49 ml/100 g/min after bypass. Angiography disclosed dilatation of donor vessels during the peak of spasm, followed by their decrease in caliber coincident with alleviation of vasospasm. The authors conclude that superficial temporal artery-middle cerebral artery anastomosis for the management of symptomatic vasospasm can increase blood flow in the ischemic region supplied by the spastic artery. This management strategy may lower the incidence of death and disability from vasospasm after subarachnoid hemorrhage.

Adult↗
PubMed1989

[Pharmacokinetic and clinical studies on cefodizime in the field of obstetrics and gynecology].

We have conducted pharmacokinetic and clinical trials of a new cephem derivative, cefodizime (THR-221, CDZM), and obtained the following results. 1. We administered CDZM to 4 cases with abdominal simple hysterectomy due to myoma uteri at a dose level of 1 g by drip intravenous injection and studied average levels of transfer measured at various locations in the uterine tissues and adnexa at an average of 2 hours after administration. CDZM level was highest in the oviduct, 13.7 micrograms/g (ratio with respect to the uterine arterial blood: 91.3%), followed by the ovary, portio vaginalis, cervix uteri and endometrium, and was lowest in the myometrium, 8.3 micrograms/g (55.3%). CDZM concentrations were higher than 6.04 micrograms/g in any tissues. 2. To study CDZM transfer to pelvic cavity fluid, we administered CDZM to 5 cases with total hysterectomy due to cervical cancer of uteri at a dose level of 2 g using drip intravenous injection. The drug was transferred at high levels to the pelvic cavity fluid. A level of 11.7 micrograms/ml was observed at 3 hours after injection. The drug levels in the pelvic cavity fluid were maintained continuously higher levels than those of venous blood. These concentrations in the uterine tissues and pelvic cavity fluid were higher than the MIC against many strains of Gram-positive and Gram-negative bacteria, hence we considered them to be therapeutically effective concentrations. 3. Eleven cases of gynecological infections receiving in totals of 8 to 48 g of CDZM demonstrated "excellent" results in 3 cases, "good" in 8 cases. Eight strains of organisms were isolated from 10 cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

[Diagnosis and treatment of fibrous adhesion into upper joint compartment of the TMJ. Part 1. Double contrast arthrotomographic findings].

A fibrous adhesion into upper joint compartment of the TMJ is indicated by a secondary pathological condition of disk displacement. The fibrous adhesion increases resistance to motion in the joint because the condyle translation has been disrupted. Fibrous adhesion cases resist splint therapy, manipulation technique and manipulation-while-pumping the upper joint compartment. Diagnosis of fibrous adhesion into upper joint compartment is important for internal derangement of the TMJ. The diagnosis depends on information from double contrast arthrotomography of the TMJ. But double contrast arthrotomography findings of fibrous adhesion into upper joint compartment of the TMJ have been recognized in few reports. We have described the varied conditions of the fibrous adhesion into the upper joint compartment of the TMJ by double contrast arthrotomographic findings. These cases confirmed the fibrous adhesion into the upper joint compartment of the TMJ by arthroscopy. Double contrast arthrotomographic findings were as follows: 1. Narrow fibrous band-like structure is observed into upper joint compartment of the TMJ. 2. A partial expansion of the upper joint compartment can be seen with a contrast medium injection. Also positional change of this stenosis decreases in both open and closed jaw positions.

Arthrography↗