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H Katayama

Publications and source records attributed to H Katayama.

At least 19 recordsLinked to original sources
PubMed1992

[Adverse reactions to low osmolar iodine contrast media (second report)].

From January to December 1990, we performed a prospective survey of adverse reactions to contrast media at two different institutes of Juntendo University. We collected a total of 4555 case sheets during the period. The radiological procedures we investigated were computed tomography, intravenous urography, arteriography, venography and myelography. Low osmolar iodine contrast medium was used almost exclusively (except for five cases). The overall incidence of adverse reactions was 7.0%, and there were no severe or fatal reactions. The incidence of adverse reactions was higher in females (8.5%) than in males (6.1%). The incidence of adverse reactions increased according to the dose of contrast medium, especially when more than 101 ml was injected. Intra-arterial injection caused adverse reactions most often, followed by regular intravenous injections, followed by bolus intravenous injections. Adverse reactions occurred most often during injection. The next occurred in 5 minutes after injection, and then, 5-10 minutes after the injection of contrast medium. The incidence of adverse reactions was higher in patients with a history of allergy or previous reactions. Allergic adverse reactions were observed at a higher frequency. Pretesting was performed in 56.7% of the cases.

Adolescent↗
PubMed1992

Re-appraisal of clinical usefulness of 67Ga-citrate scintigraphy for primary colorectal carcinoma: with evaluation of scintigram obtained from resected specimens.

Clinical usefulness of 67Ga-citrate scintigraphy for the diagnosis of colorectal carcinoma was reappraised at the standpoint of clinicopathological diagnosis. Fifty-eight patients with colonic carcinoma were subjected to this study. They underwent 67Ga scintigraphy before surgery. Colorectal carcinomas were detected in 38 patients, 65.5% by this procedure. Surgical specimens from thirty-seven patients underwent postoperative scanning. The scanning of the surgical specimen revealed accumulation of 67Ga-citrate in all 37 patients, suggesting that 67Ga-citrate accumulated in the carcinoma of the colon. The results suggested that detectability of carcinoma of the colon by 67Ga scintigraphy in this series was better than generally considered. 67Ga scintigraphy was considered to provide useful information in cases of severe stenosis and dolichocolon which were difficult to diagnose with a Barium enema and fiberscope. The problem is that abnormal accumulation is sometimes hard to distinguish from physiological excretion in the stools. However we believe that images should be carefully evaluated, keeping in mind the fact that 67Ga-citrate could accumulate in a colorectal carcinoma, and also believe that we radiologists should actively promote Ba-enema examination in positive cases rather than to devote time to the differentiation between physiological excretion of 67Ga in the stools and accumulation in a colorectal carcinoma.

Adenocarcinoma↗
PubMed1992

Cutaneous T-cell lymphoma associated with granular lymphocytic leukemia in its terminal stage.

A 79-year-old woman had cutaneous T cell lymphoma. After a long clinical course, numerous tumors and an enormous increase in peripheral granular lymphocytes without lymphadenopathy developed suddenly. Surface markers and DNA analysis of the tumor cells from her skin and peripheral blood and electron microscopic examination suggested that granular lymphocytic leukemia had developed in the terminal stage of cutaneous T cell lymphoma. To our knowledge this association has not been reported previously.

Acute Disease↗
PubMed1992

Application of curdlan to controlled drug delivery. I. The preparation and evaluation of theophylline-containing curdlan tablets.

To study the use of curdlan, a natural beta-1,3-glucan, in drug delivery, in vitro release studies were carried out with curdlan tablets containing theophylline. Tablets were readily prepared by compressing three different curdlan and theophylline mixtures, namely, a physical mixture, spray-dried curdlan particles with theophylline powder, and spray-dried particles of curdlan/theophylline solution. Drug release from the tablets prepared from spray-dried particles of curdlan/theophylline was lowest. The release rate was constant from 1 to 8 hr, and 59% cumulative release was obtained at 8 hr. Drug release from curdlan tablets was unaffected by pH or various ions; these curdlan tablets might also control drug release in vivo after oral administration. Application of Higuchi's equation indicated that drug release from curdlan tablets was diffusion-controlled. The release profiles of the curdlan tablets were compared to those of a commercial theophylline sustained-release tablet.

Chemistry, Pharmaceutical↗
PubMed1992

Modification of the clastogenic activity of X-ray and 6-mercaptopurine in mice by prefeeding with vitamins C and E.

The effect of a 30-d pretreatment with vitamin C (L-ascorbic acid) in the drinking water and vitamin E (all-rac-alpha-tocopherol) in the diet on the clastogenic activity induced by X-rays and 6-mercaptopurine was investigated in female ICR/Jcl mice by the bone-marrow micronucleus test. Prefeeding with vitamin E-deficient diets led to a significant decrease in serum vitamin E concentration and to an enhancement of micronucleus formation by X-rays in bone marrow cells. Although dietary supplementation with vitamin E significantly increased the vitamin E concentration in serum, it did not affect the frequency of X-ray-induced micronuclei. Treatment with a high level of vitamin C in drinking water was effective in protecting against micronucleus formation by X-rays. The increase in micronucleus frequency in the vitamin E-deficient mice compared with the mice fed vitamin E-normal diets was no longer observed when a high level of vitamin C in drinking water was given simultaneously. The most efficient protective action against X-rays was observed when vitamin E-supplemented diets and a high level of vitamin C in drinking water were used together as a pretreatment. Any combination of the vitamins did not affect the micronucleus induction by 6-mercaptopurine.

Animals↗
PubMed1992

A novel method to analyse response patterns of taste neurons by artificial neural networks.

Despite several notions on the gustatory code proposed over three decades, investigators have not yet reached a consensus. This paper describes a new approach to analyse gustatory neural activities. Three-layer neural networks were trained by the back-propagation learning algorithm, to classify the neural response patterns to four basic taste qualities. The discrimination by the trained networks on taste qualities in the response patterns of rat chorda tympani fibres (CT) and cortical taste neurons (CN) was consistent both with the correlation analysis and with behavioural experiments. By examining the connection weights of each neuron, some input neurons representing CN were 'pruned' without deteriorating the ability of the network to discriminate taste. This characteristic of the network is contrary to a previous hypothesis, that taste neurons are of equal importance in the neural coding.

Animals↗
PubMed1992

Stroke volume and cardiac output decrease at termination of obstructive apneas.

Patients with obstructive sleep apnea (OSA) experience repetitive nocturnal oscillations of systemic arterial pressure that occur in association with changes in respiration and changes in sleep state. To investigate cardiac function during the cycle of obstruction (apnea) and resumption of ventilation (recovery), we continuously measured left ventricular stroke volume (LVSV) and mean arterial blood pressure (MAP) during non-rapid-eye-movement sleep in six males with severe OSA (apnea/hypopnea index > or = 30 events/h associated with oxygen saturation < 82%). LVSV was assessed continuously using an ambulatory ventricular function monitor (VEST; Capintec). The apnea-recovery cycle was divided into three phases: 1) early apnea (EA), 2) late apnea (LA), and 3) recovery (Rec). In all subjects recovery was associated with an abrupt decrease in LVSV [54.0 +/- 14.5 (SD) ml] compared with either EA (91.4 +/- 14.7 ml; P < 0.001) or LA (77.1 +/- 15.2 ml; P < 0.005). Although heart rate increased with recovery, the increase was not sufficient to compensate for the decrease in LVSV so that cardiac output (CO) fell (EA: 6,247 +/- 739 ml/min; LA: 5,741 +/- 1,094 ml/min; Rec: 4,601 +/- 1,249 ml/min; EA vs. Rec, P < 0.01; LA vs. Rec, P < 0.025). Recovery was also associated with a significant increase in MAP. We speculate that such abrupt decreases in LVSV and CO at apnea termination, occurring coincident with the nadir of oxygen saturation, may further compromise tissue oxygen delivery.

Adult↗
PubMed1992

Three-dimensional visualization of pulmonary blood flow velocity profiles in lambs.

For a better understanding of the characteristics of blood flow in the pulmonary artery, we constructed three-dimensional images of velocity profiles of blood flow in the pulmonary artery from pulsed Doppler ultrasound recordings in 14 lambs aged 28-40 days. In 8 lambs, pulmonary hypertension was created by the central venous injection of monocrotaline pyrrole. Six lambs served as unaltered controls. The velocity data were sampled in 2 mm increments along both an anterior-posterior axis and a right-left orthogonal axis in the main pulmonary artery. Using a computer-generated cross-sectional velocity matrix consisting of 0.25 mm square grids, the velocity of blood flow was estimated at each intersection. The cross-sectional velocity matrices were generated at 5 msec intervals during the entire cardiac cycle. In all animals, significant velocity reversal was detected near the posterior wall. In 7 of 14 animals, the peak forward velocity was located near the posterior wall. Three of 8 hypertensive models showed reacceleration during the mid-systolic phase at the center of the velocity waveform, but one reacceleration disappeared at a point only 2 mm away from the center of the vessel toward the posterior wall. Acceleration time correlated well with the mean pulmonary arterial pressure (PAP) (r = -0.85) and the log10 PAP (r = -0.86). Corrected acceleration time (acceleration time divided by the square root of the cardiac cycle length) also correlated with PAP (r = -0.78) and the log10 PAP (r = -0.81).

Animals↗
PubMed1992

[Influence of nicardipine on the renin-angiotensin system ina hypertensive crisis during operation in elderly patients].

We studied the influence of nicardipine on renin-angiotensin (RA) system in twelve elderly patients, because the suppression of RA system, the decrease in reactivity of its feedback mechanism, and a high probability of arteriosclerosis and hypertension are well recognized in elderly patients. In hypertensive crisis during operation, intravenous bolus injection of nicardipine was done promptly by anesthesiologists in charge. Plasma renin activity (PRA), angiotensin I (A I), and angiotensin II (A II) were measured with RIA methods before administration of nicardipine and after hemodynamics were stabilized. Changes of systemic arterial pressure and heart rate were simultaneously recorded. Concentrations of PRA, A I, and A II were not significantly elevated, whereas systemic and diastolic blood pressures decreased significantly at 5 min, 15 min, 30 min and 60 min after administration of nicardipine. Heart rate was unchanged. But in a few cases there was an increase in PRA and A I. Average total dose of nicardipine was 26.8 micrograms.kg-1 and average fall of blood pressure was 23.9%. In conclusion, we can use intravenous nicardipine safely and stabilize hemodynamics easily without activation of RA system and rebounding of its feedback mechanism.

Aged↗
PubMed1992

[81mKr scintigraphic evaluation of hemodynamics in gynecologic malignancies under condition of angiotensin II-induced hypertension].

Transcatheter arterial infusion chemotherapy is one of the most useful therapeutic procedures for gynecologic malignancies. Recently, several reports have been published about Angiotensin II-induced hypertension chemotherapy and the efficacy of the method, but there have been no reports to evaluate an application for gynecologic malignancies. We evaluate the usefulness of the method for gynecologic malignancies demonstrating the changes of hemodynamics of the tumor using 81mKr scintigraphy. Thirteen patients with pathologically confirmed gynecologic malignancies were evaluated by angiography and continuous infusion of 81mKr via the catheter with and without Angiotensin II. At first, continuous infusion of 81mKr was performed under the superselective catheterization of the uterine artery. The radioactivities in the ROI were counted. Then, withdrew the catheter from the uterine artery to the internal iliac artery, and again continuously infused 81mKr and counted the radioactivities in the same ROI. Finally, keeping the catheter in the internal iliac artery, Angiotensin II and 81mKr were infused simultaneously. And counted the radioactivities. The radioactivities were highest when the catheter tip was placed in uterine arteries and lowest when the catheter tip was placed in internal iliac arteries. But radioactivities in the ROIs were definitely increased when Angiotensin II was used, even if the catheter tip was keeping in the internal iliac arteries. The optimal catheter position of transcatheter arterial chemotherapy for gynecologic malignancies is at proximal uterine artery. Since Angiotensin II-induced hypertension may increase blood flow of tumors, it seems to have indication for post-operative cases, highly advanced cases and cases with difficulties to perform superselective catheterization.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

[A case of bronchospasm during induction of isoflurane anesthesia].

Isoflurane is generally considered to prevent increase in bronchomotor tone. We report a case of bronchospasm associated with exposure to isoflurane. A 11-year-old girl was scheduled for tonsillectomy because of repeated fever. Anesthesia was induced with nitrous oxide, oxygen and sevoflurane. Sevoflurane was switched to isoflurane and increased gradually to 3%. Shortly after inhalation of isoflurane, eruption at chest appeared and auscultation of the chest revealed dry rale. Aminophylline and hydrocortisone were injected and isoflurane was discontinued. Ventilation with sevoflurane was started, but there was no improvement. Intramuscular epinephrine was given and sevoflurane was discontinued. After this, the wheezing improved. Four days later she underwent tonsillectomy under sevoflurane anesthesia uneventfully.

Anesthesia, Inhalation↗
PubMed1992

[Appropriate puncture site for CT monitored celiac plexus block determined from CT films].

We investigated appropriate puncture site, angle of needle entry, and the distance of the insertion for CT monitored celiac plexus block using CT photograms on prone position in sixteen patients with gastrointestinal diseases. In retrocrural approach during CT monitored celiac plexus block, the average distances of puncture sites to midline were 3.84 cm on the right and 4.06 cm on the left, and the average needle angles were 74.1 degrees on the right and 76.9 degrees on the left. The average depths from the puncture site to marked position in retrocrural space were 7.88 cm on the right and 7.85 cm on the left. The rates of predicted organ puncture when needle is inserted 7 cm lateral to the midline of the spinal process were 43.8 percent in the right lung, 12.5 percent in the left lung, 56.2 percent in the right kidney and 68.8 percent in the left kidney. From these results, we found high possibilities of organ injuries using the conventional technique for celiac plexus block. We conclude that we could perform celiac plexus block more safely and surely using the retrocrural approach by CT monitoring, as serious complications are avoidable by viewing ideal puncture course on CT photographs.

Aged↗
PubMed1992

[Levofloxacin in the field of dermatology].

1. Minimum inhibitory concentrations (MICs) of levofloxacin (LVFX, DR-3355), ofloxacin (OFLX), tosufloxacin (TFLX), norfloxacin (NFLX) were determined, with an inoculum size of 10(6) cfu/ml, against 122 strains of Staphylococcus aureus isolated from lesions of skin infections. LVFX showed most frequent MIC values of 0.20 micrograms/ml. OFLX, TFLX, and NFLX showed most frequent MIC values of 0.39 micrograms/ml, less than or equal to 0.05 micrograms/ml and 0.78 micrograms/ml, respectively. 2. Serum and skin levels of LVFX after oral administration (10 mg/kg, fasting) were determined in rats. Serum levels were 1.79, 1.29, 0.60, 0.43 and 0.18 micrograms/ml, and corresponding skin levels were 1.63, 1.77, 1.04, 0.87 and 0.64 micrograms/g (wet weight) at 0.5, 1, 2, 4 and 8 hours after administration (n = 5), respectively. 3. LVFX was used clinically in 43 cases at doses of 200-300 mg divided into 2 or 3 doses, and evaluated for final overall clinical efficacy in 41 cases. Cure was observed in 21 cases, remarkable improvement in 13 cases, improvement in 4 cases, unchanged in 1 case, aggravation in 1 case, and remarkable aggravation in 1 case. Diarrhea was observed in 2 cases, diffuse erythema with feverishness in 1 case and slight dyspnea in 1 case. Transient slight eosinophilia, elevation of Al-P, anemia and leukopenia were observed.

Adolescent↗
PubMed1991

[Adverse reactions to low osmolar iodine contrast media].

From January 1989 to December 1989, we performed a prospective survey of adverse reactions to contrast media at three institutes of Juntendo University. We collected a total of 4365 case cards during the period. Low osmolar iodine contrast media were given in all but one case. Procedures using contrast media included computed tomography, intravenous urography, arteriography, venography and myelography. The overall incidence of adverse reactions was 6.6%, and there were no severe or fatal reactions. The incidence of adverse reactions was about the same in both sexes. However, in males, the incidence was higher in the fifth decade, and in females, it was higher in the third and seventh decades. There was no relation between the dose of contrast medium and adverse reactions. Intravenous bolus injections caused adverse reactions more often, followed by intra-arterial injections and then usual intravenous injections. The incidence of adverse reactions in patients with a history of allergy or previous reactions was higher. Pretesting was performed in 48.9% of the cases.

Angiography↗
PubMed1991

Linear lupus erythematosus profundus in a child.

A 9-year-old Japanese boy had a 6-year history of a linear eruption of the left leg. It was characterized histopathologically by an intense lymphocytic panniculitis, perivascular and periappendageal infiltrates of lymphocytes, and vacuolization of the basal cell layer. This case represents a clinical presentation of linear lupus erythematosus profundus not previously reported.

Basement Membrane↗
PubMed1991

Hemodynamic effects of endothelin-1 in the newborn piglet: influence on pulmonary and systemic vascular resistance.

The aim of this study was to investigate the influence of endothelin-1 (ET-1) on the pulmonary and systemic circulations in newborn piglets. Twelve piglets (mean age of 6.8 days, range of 1-12 days) were anesthetized with chloralose-urethane and ventilated at FiO2 = 1.0. Animals were instrumented to measure cardiac output (CO), pulmonary artery pressure (PAP), aortic pressure (AoP), left atrial pressure (LAP), and right atrial pressure (RAP). Six piglets received a control saline injection into the pulmonary artery (PA), and six piglets received one injection of ET-1 (500 ng/kg) into the PA while PAP, AoP, LAP, RAP, CO, and heart rate (HR) were measured simultaneously at 20-s intervals with pulmonary vascular resistance (PVR) and systemic vascular resistance (SVR) calculated by computer. Administration of ET-1 into the PA led to (a) a transient decrease in mean PAP (delta max of -4 +/- 2 mm Hg, p less than 0.001); (b) a biphasic response (an initial decline followed by a substantial increase) in PVR (delta max of -760 +/- 460 dyn cm/s5, p less than 0.01, and delta max of +1,490 +/- 1,360 dyn cm/s5, p less than 0.05) and in AoP (delta max of -12 +/- 7 mm Hg, p less than 0.005, and delta max of +11 +/- 6 mm Hg, p less than 0.005); (c) an increase in SVR (delta max of +5,930 +/- 2,330 dyn cm/s5, p less than 0.05); and (d) an initial increase in CO (delta max of +0.06 +/- 0.03 L/min, p less than 0.05) followed by a decrease (delta max of -0.09 +/- 0.05 L/min, p less than 0.05). These responses have not been observed in adult species and may indicate a developmental difference in the response of the pulmonary circulation to ET-1 administration.

Animals↗