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K Kitamura

Publications and source records attributed to K Kitamura.

At least 955 records · Page 53Linked to original sources
PubMed1988

Activation of the coagulation system in the subarachnoid space after subarachnoid haemorrhage: serial measurement of fibrinopeptide A and bradykinin of cerebrospinal fluid and plasma in patients with subarachnoid haemorrhage.

Fibrinopeptide A (FPA) levels as an indicator of thrombin activity in the cerebrospinal fluid (CSF) and plasma of 25 patients with subarachnoid haemorrhage (SAH) were measured serially by radioimmunoassay (RIA). FPA levels in CSF were extremely high on days 0-1 (1253 +/- 269 ng/ml, mean +/- standard error) but decreased rapidly (11.3 +/- 3.9 ng/ml on days 2-4, 10.7 +/- 5.9 ng/ml on days 5-7, and 6.3 +/- 1.5 ng/ml on days 8-14). In the controls the FPA concentration in CSF was 1.2 +/- 0.9 ng/ml (mean +/- standard deviation). Plasma FPA levels in patients with SAH showed no statistically significant changes with time. The bradykinin (BK) concentration in CSF and plasma in 27 patients with SAH was measured serially by RIA. The concentrations in CSF were 122.7 +/- 22.7 pg/ml (mean +/- standard error) on day 0, 38.6 +/- 6.1 pg/ml on day 1, 22.7 +/- 6.3 pg/ml on day 2, and 17.1 +/- 3.0 pg/ml or less thereafter. Plasma BK levels in patients with SAH were higher than those in the control group, but there was no statistically significant change over time. From the measurement of FPA it was apparent that the coagulation system in the subarachnoid space is strongly activated in the early stage of SAH. The formation of BK in CSF after SAH is thought to be due to the contact activation of Hageman factor (intrinsic factor) in the subarachnoid space. Trabeculae as collagen bundles in the subarachnoid space were considered to have a possible role in activating the Hageman factor of the coagulation system in SAH.

Adult↗
PubMed1988

Effects of inositol phosphates on the membrane activity of smooth muscle cells of the rabbit portal vein.

The effects of intracellular perfusion of inositol 1,4,5-trisphosphate (InsP3) or inositol 1,3,4,5-tetrakisphosphate (InsP4) on electrical responses of smooth muscle cell membranes of the rabbit portal vein were studied using the whole cell voltage clamp technique. Depolarisation to 0 mV from a holding potential of -60 mV, evoked inward Ca (Ica), transient outward (ISO), oscillatory outward (IOO) and sustained outward (ISO) currents. Generation of IOO was dependent on the [Ca]o, but it was also generated in 0 mM Ca solution for over 10 min. From amplitude histograms, IOO was divided into two components. Reduction in [Ca]o inhibited the appearance of but not the amplitudes of both IOO components. However, the larger component of IOO was more resistant to a reduction in [Ca]o than the smaller one. InsP3 (10 microM) increased the frequency of both IOO components to a greater extent than their amplitude, but the larger component was more sensitive to InsP3 than the smaller one. The increase in the occurrence of IOO induced by InsP3 did not occur following pretreatment with 3 mM caffeine or 1 nM A23187. In normal PSS, InsP3 was evoked by a depolarising pulse positive to -40 mV, whereas following perfusion with InsP3 (10 microM), IOO was evoked at -60 mV. In normal PSS, intracellular perfusion with 10 microM InsP4 changed neither the frequency nor the amplitude of IOO, and the amplitudes of ICa, ITO and ISO were also unchanged. However, in 10 mM Ca solution, 10 microM InsP4 generated IOO at a membrane potential of -60 mV.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1988

A rapid immunostaining method for scirrhous gastric cancer during surgery using a monoclonal antibody.

In the microscopic examination of gastric cancer, it is sometimes difficult to identify scirrhous carcinoma cells, because they grow individually into the fibrous tissue. In this study we used an anti-scirrhous carcinoma monoclonal antibody S202, which was reactive with 100 per cent of the cells belonging to this type of carcinoma, in a rapid immunostaining procedure to identify the limit of tumor invasion at the time of surgery. S202 was applied using this new immunostaining method and the results compared with those obtained by the routine immunohistological method. Five minutes incubation was sufficient to stain the tumor cells with biotin-conjugated S202 and the entire procedure took only 14-15 mins. There was no difference between the new and routine methods in terms of distribution of S202-positive carcinoma cells. This rapid staining method enabled a clearer recognition of infiltrating tumor cells in the frozen sections of tissue specimens, than was previously possible. This technique will thus make it possible to determine the limit of tumor extension in resected tissues accurately and rapidly during surgery.

Adenocarcinoma, Scirrhous↗
PubMed1988

Histological diagnosis of scirrhous carcinoma of the stomach using monoclonal antibody S202.

It is sometimes difficult to identify scirrhous carcinoma cells microscopically, since individually separated malignant cells grow into the fibrous tissue without glandular formation. In this study, we used anti-scirrhous carcinoma monoclonal antibody S202, which reacted strongly with 100% of scirrhous gastric cancer samples, in order to evaluate the precise depth to which cancer cells invaded in the stomach wall. The invasive carcinoma cells could be detected more clearly by immunohistochemical staining with S202 than by histological staining with hematoxylin-eosin. Furthermore, S202 was more useful than anti-CEA (carcinoembryonic antigen) antibody.

Adenocarcinoma, Scirrhous↗
PubMed1988

A case of moyamoya disease with progressive involvement from unilateral to bilateral.

A case of Moyamoya disease in a child starting with unilateral lesion and developing into bilateral involvement is reported. Angiographic findings at onset showed unilateral involvement, hence, it was filed as a "probable" case according to the diagnostic criteria of the Japanese Cooperative Research Committee. The carotid angiograms, on the other side were totally normal. Three years later the occlusive lesion became bilateral, to meet the criteria as a "definite" case. Clinical manifestations, angiograms, electroencephalograms, and positron emission tomograms in this case are presented, and the relation between the probable and definite cases is discussed.

Arterial Occlusive Diseases↗
PubMed1988

Gliomas with dural invasion: computed tomography and angiography.

This report is a review of the findings of computed tomography and angiography of eight supratentorial gliomas with dural invasion. Computed tomography revealed localized increases in the thickness of ring enhancements at the sites of dural invasion in four cases, which was attributed to increased blood supplies by the meningeal vessels. Angiographically, feeders from the meningeal vessels entered the tumors mostly through relatively broad areas of tumor-dura attachment. A sunburst type of neovascularity from a meningeal artery was seen in only one case. In most such cases the differential diagnosis from meningioma was possible by the computed tomographic and angiographic findings. Selective external carotid angiography was the most important examination for diagnosing dural invasion by gliomas.

Astrocytoma↗
PubMed1988

Sensitivity and accuracy in recording His-Purkinje activity by surface-averaged electrocardiography.

A clinical evaluation of the surface-averaged ECG (SAE) to record His-Purkinje activity (HPA) was made on 70 patients who underwent His bundle electrograms (HBE). The recorded signals first judged as HPA in 43 patients by the noninvasive method alone were later verified in 37 patients by HBE; the accuracy of the HPA recordings (predictive value) was 86.0%. The HPA-V interval measured noninvasively had a high correlation with the HV interval by HBE (r = 0.89, p less than 0.01). The verified detection rate in all 70 patients was 52.9%: HPA was detected in 12 of 18 patients (66.7%) with sclerotic and hypertensive heart disease (Group I), five of 19 patients (26.3%) with rheumatic heart disease (Group II), 11 of 17 patients (64.7%) with congenital heart disease (Group III), and nine of 16 patients (56.2%) with miscellaneous conditions (Group IV). The detection rate was markedly lower in Group II than in other groups (Group II vs Group I or III, p less than 0.025). The PR segment was significantly longer in the patients in whom HPA was detected than in those in whom it was not detected (71.5 +/- 22.3 msec vs 43.9 +/- 19.5 msec, p less than 0.001). His-Purkinje activity (HPA) was detected in 32 of 52 recordings (61.5%) with sinus rhythm and seven of 20 recordings (35.0%) with atrial fibrillation, including two recordings in each of two cardioverted patients (p less than 0.05). We conclude that the surface-averaged ECG (SAE) has clinically acceptable sensitivity and accuracy except in patients with rheumatic heart disease, short PR segments or atrial fibrillations.

Atrial Fibrillation↗
PubMed1988

Microexplosion cystolithotripsy in 105 cases.

We treated 105 consecutive patients with bladder calculi by microexplosion lithotripsy, with a success rate of 100 per cent. The weight of the removed calculi averaged 18 gm., with a range of 2 to 305 gm. For the procedure spinal anesthesia was used in 78 patients, while general anesthesia was used in 24. Minor extraperitoneal bladder perforation occurred only once and it resolved spontaneously several days later. Presently, we consider microexplosion lithotripsy to be the treatment of first choice for bladder calculi.

Adolescent↗
PubMed1988

Characteristics of cromakalim-induced relaxations in the smooth muscle cells of guinea-pig mesenteric artery and vein.

1. The effects of cromakalim (BRL 34915) on the smooth muscle cells of guinea-pig mesenteric artery and vein were investigated with microelectrode and tension recording methods. 2. Cromakalim (greater than 10 microM) produced membrane hyperpolarization with an increase in ionic conductance. The hyperpolarization occurred to a greater extent and lasted longer in the vein than in the artery. 3. The hyperpolarization induced by cromakalim in mesenteric vein comprised two components, one of which was Mn sensitive. In mesenteric artery, the hyperpolarization was relatively insensitive to Mn. 4. From the current-voltage relationship measured from arterial smooth muscle membranes, the reversal potential of cromakalim was estimated to be -80 mV. The cromakalim-induced hyperpolarization was not modified in Na- or Cl-deficient solution. 5. In both mesenteric artery and vein, cromakalim relaxed tissues precontracted with high K with (below 40 mM) or without (above 40 mM) hyperpolarization of the membrane. 6. In the mesenteric artery, action potentials evoked by electrical stimulation ceased before the generation of hyperpolarization. 7. Cromakalim produced a cross-desensitization with nicorandil on the evoked membrane hyperpolarization in mesenteric artery. 8. It is concluded that the relaxing actions of cromakalim result from the hyperpolarization which follows the opening of Ca-dependent K channels. The inhibition of a voltage-dependent Ca current may also be involved in this inhibitory effect.

Action Potentials↗
PubMed1988

Ryanodine inhibits the Ca-dependent K current after depletion of Ca stored in smooth muscle cells of the rabbit ileal longitudinal muscle.

1. Effects of ryanodine on the membrane currents were investigated on dispersed smooth muscle cells of rabbit ileal longitudinal layer using voltage and patch clamp procedures. 2. With voltage clamp, membrane depolarization to 0 mV from the holding potential of -60 mV produced an inward Ca current (ICa) which was followed by transient and sustained outward currents (ITO and ISO, respectively). Prolonged depolarization of the membrane produced spontaneous oscillations of the outward current (oscillatory outward current; IOO) on ISO. 3. Ryanodine (30 microM) modified neither the basal membrane current recorded at the holding potential (-60 mV) nor ISO. Ryanodine inhibited both ITO and IOO in a concentration-dependent manner (IC50 = 5.5 and 4.5 microM, respectively, measured 12 min after application of ryanodine). These values were much higher than that observed in skeletal muscle for Ca release. 4. The time course of the ryanodine-induced inhibition of IOO was slow and the inhibition was irreversible. Caffeine (3 mM) enhanced the amplitudes of ITO and IOO in the presence of Ca, and only transiently enhanced IOO in the absence of Ca. However, following application of 10 microM ryanodine, 3 mM caffeine did not increase IOO. 5. Ryanodine (3-30 microM) slightly enhanced the amplitude of ICa evoked by depolarization pulses at potentials more negative than O mV but not that induced by larger depolarizations (positive potentials). 6. With patch clamp procedure, single Ca-dependent K channel currents were recorded in cell free and cell attached configurations. Application of 30 microM ryanodine transiently enhanced the Ca-dependent K current without any detectable changes in the amplitude of the single channel current recorded in the cell attached condition. In the inside-out membrane patch, when the intracellular membrane side was superfused with 1 microM Ca buffered with 10 mM EGTA, bath application of 10 microM ryanodine had no effect on the Ca-dependent K current. 7. It was concluded that both ITO and IOO are generated by Ca released from intracellular stores, mainly sarcoplasmic reticulum. Ryanodine appears to open irreversibly the Ca channel in the store and to inhibit the Ca-dependent K channel due to depletion of the stored Ca.

Alkaloids↗
PubMed1988

Regulation of calcium current by intracellular calcium in smooth muscle cells of rabbit portal vein.

Effects of concentrations of intracellular calcium, [Ca2+]i, on the voltage-dependent Ca2+ current (ICa) recorded from dispersed single smooth muscle cells of the rabbit portal vein were studied, using a whole cell voltage clamp method combined with an intracellular perfusion technique. Outward currents were minimized by replacement of Cs+ -rich solution in the pipette and 20 mM tetraethylammonium in the bath. The ICa was evoked by command pulses of above -30 mV, and the maximum amplitude was obtained at about 0 mV. This ICa was dose dependently inhibited by increases in the [Ca2+]i above 30 nM. The Kd value of the [Ca2+]i required to inhibit the ICa was about 100 nM. The Ba2+ current was also inhibited by increases in the [Ca2+]i. Conversely, perfusion of Ba2+ into the cell up to 100 microM did not suppress the ICa. Changes in the [Ca2+]i did not modify the steady-state inactivation curve. The inhibition of the ICa evoked by the test pulse is most prominent when the preceding influx of Ca2+ during the conditioning pulse was large, as estimated using a double pulse protocol. This inhibition was proportionally reduced by increases in the concentration of the Ca2+ chelator, ethylene glycol bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid (EGTA). Therefore, the Ca2+ -dependent inactivation of the Ca2+ channel may contribute toward regulating [Ca2+]i in smooth muscle cells of the rabbit portal vein.

Animals↗
PubMed1988

Capillary permeability and boron distribution in ethylnitrosourea-induced rat glioma.

The vasculature and capillary permeability of gliomas induced by ethylnitrosourea in Sprague-Dawley rats were studied with horseradish peroxidase and Evans blue dye. The distribution of the boron-10 compound, Na2(10)B12H11SH, which is now in clinical use for boron neutron capture therapy (BNCT) for brain tumors, was investigated quantitatively using neutron-induced alpha-autoradiography. The vasculature and the degree of capillary permeability varied widely, depending mainly on the size of the glioma, and were often heterogeneous even in the same tumor. The distribution of boron-10 also varied, correlating to capillary permeability. The boron-10 concentration and the tumor:blood concentration ratio in large and medium-sized gliomas were adequate for successful BNCT. This study suggests that the vasculature and capillary permeability of the target brain tumor exert an important influence on the therapeutic efficacy of BNCT.

Animals↗
PubMed1988

Diagnosis and surgical treatment of spasmodic torticollis of 11th nerve origin.

Of 22 patients with spasmodic torticollis, 7 were treated by microsurgical decompression of the 11th nerve. In these patients, there was an intermittent horizontal torticollis characterized by aggravation of the symptoms when in a resting posture, presenting with a striking contrast to the torticollis of extrapyramidal origin that was alleviated while in the resting posture and aggravated by postural stress. A tight neurovascular contact was observed at the C1 level, occurring between the principal 11th nerve and the vertebral or posterior inferior cerebellar artery. Nerve decompression was achieved in 2 by transposing the compressing artery and in 5 by sectioning at C1 or C2 the branching root of the 11th nerve that had caused the tight cross contact by locking the nerve trunk to the dura mater. The symptoms had improved after an interval of 1 to 4 weeks. After an average follow-up of 3 years, full or satisfactory relief had been obtained in 5 and some improvement had occurred in 2 patients. Possible neural mechanisms related to torticollis of 11th nerve origin are discussed.

Accessory Nerve↗