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Biomedical subjects

A Araki

Publications and source records attributed to A Araki.

At least 73 records · Page 4Linked to original sources
PubMed1991

Na+/H+ exchange modulates rat neutrophil mediated tumor cytotoxicity.

Rat neutrophils stimulated with phorbol 12-myristate 13-acetate, Bacillus Calmette-Guérin, zymosan A, and beta-1,3-D-glucan from Alcaligenes faecalis showed cytotoxicity to various tumor cells. Hydrogen peroxide was shown to be an effector molecule in tumor cytotoxicity by inhibition using various active oxygen scavengers. The following findings suggest that tumor cytotoxicity by rat neutrophils stimulated with the four reagents mentioned above is regulated by Na+/H+ exchange: (a) an increase in extracellular pH (pHo) from 6.5 to 8.0 resulted in enhancement of both tumor cytotoxicity and H2O2 production; (b) amiloride and its derivatives, inhibitors of Na+/H+ exchange, inhibited both functions of neutrophils mentioned above; (c) amiloride reduced intracellular pH (pHi) of neutrophils stimulated with the four reagents; (d) a decrease in the extracellular concentration of Na+ [( Na+]o) inhibited H2O2 production; (e) monensin, a Na+/H+ exchange ionophore, enhanced tumor cytotoxicity by neutrophils.

Amiloride↗
PubMed1991

Differentiation of central lung tumor from postobstructive lobar collapse by rapid sequence computed tomography.

When central lung tumor is associated with lobar collapse, discrimination of tumor from atelectasis is important for determining operability or for field planning should radiation therapy be utilized. Because tumor and collapsed lung have similar attenuation values, they cannot always be distinguished with usual contrast-enhanced CT. The article describes separation of tumor from collapsed lung by means of RSCT with bolus injection of nonionic contrast medium. With this technique collapsed lung is appreciably enhanced, but tumor enhancement is slow and minimal. The difference is most marked from 40 seconds to 2 minutes after scanning begins. This phenomenon is probably related to the marked increase in blood flow per unit area of collapsed lung due to crowding of relatively large pulmonary arteries compared to tumor blood supply through small bronchial arteries. Tumor can also be delineated from atelectasis by differences in internal structure with this technique.

Aged↗
PubMed1991

[Bilateral acute profound deafness after MMR vaccination--report of a case].

In April 1989 the MMR vaccination program had started, and until October, 1989, 630,000 children received vaccination. In is, however, well known that many children developed various complication including aseptic meningitis after vaccination, and the MMR vaccination program has discontinued. This report described a case of bilateral acute profound deafness most likely due to MMR vaccination. The cause of this deafness was presumed to be mumps vaccination. The bases of the presumption are as follows: the meningitis after MMR vaccination was elicited by PCR method to be caused by mumps vaccine, and the complication of CNS after measles vaccination occurs within 14 days after injection, while the onset of vomiting and gait disturbance of the case was 24 days after vaccination.

Acute Disease↗
PubMed1991

[Auditory brainstem response and extratympanic recorded electrocochleography in patients with multiple and severe handicaps].

Nine patients ranged between 5 months and 35 years (means 14 years) of age with multiple and severe disabilities were comparatively studied, on extra-tympanic recorded compound action potential (AP) of electrocochleography and auditory brainstem response (ABR). Both ABR and AP were obvious in 3 patients with clear auditory behavioral responses. The ABR was not recorded to high intensity click stimuli in six patients without visible auditory behavioral responses. Four of the 6 cases showed undetectable AP and the 2 rest of the 6 cases showed abnormal but discernible AP. In two cases with history of the anoxic encephalopathy, AP was recorded but ABR was not detected in one case, and in the other, neither AP nor ABR was recorded. At least two different levels of lesions could be differentiated in cases without detectable ABR by using extra-tympanic recorded electrocochleography in these kinds of severely handicapped patients.

Action Potentials↗
PubMed1991

[Evaluation of pulmonary emphysema with high resolution computed tomography and the effect of smoking].

Cigarette smoking is thought to play an important part in the development of pulmonary emphysema. The authors previously reported on the correlation of high resolution computed tomography (CT) with the pathology grade of emphysema and the destructive index of lung specimens from 42 patients undergoing thoracotomy for a solitary pulmonary nodule. High resolution CT was effective to identify the presence and grade of mild emphysema. The mean per cent predicted FEV1 was 97 per cent. There were 28 smokers and 14 nonsmokers. In this report, the correlation of smoking history with pathology score and high resolution CT was analyzed. There was significant correlation among these indices. These results further support the relationship between smoking and pulmonary emphysema. High resolution CT scan may help in the understanding of the role of cigarette smoking in the development of early pulmonary emphysema.

Adult↗
PubMed1991

[Congenital neuromuscular disease with uniform type 1 fibers : a case report].

A 3-year-old boy was seen because of delayed developmental milestones, waddling gait, nonprogressive proximal muscle weakness and hyporeflexia. Serum creatine kinase levels were normal and EMG was non-diagnostic. Muscle biopsy revealed complete absence of type 2 A and 2 B fibers in addition to a moderate variation in fiber size. Diagnostic findings for congenital nonprogressive myopathies were not present such as nemaline bodies, cores, targetoid structure, central nuclei or selective type 1 fiber atrophy. This was the first case of a distinct form of non-progressive congenital myopathy, "congenital neuromuscular disease (myopathy) with uniform type 1 fibers", accompanied with mental retardation in Japan.

Child, Preschool↗
PubMed1990

The effect of L-carnitine supplementation in 4 pentenoic acid treated rats.

The effects of prolonged administration (7 days) of 4 pentenoic acid (4PA, 20 mg/kg/day) or 4PA (20 mg/kg/day) with L-carnitine (200 mg/kg/day) on carnitine metabolism and morphological changes of liver mitochondria were assessed in rats. 4PA-treated rats showed hyperammonemia, decreased levels of blood glucose, free fatty acids and beta-OH-butyrate, and of free carnitine in serum, muscle and liver, increased excretion of acylcarnitine in urine, and enlarged mitochondria with microvesicular steatosis, when compared to saline-injected control rats, respectively. 4PA plus L-carnitine rats showed decreased levels of blood ammonia and increased levels of beta-OH-butyrate, compared to the 4PA group. On the other hand, the levels of free carnitine in serum and liver in rats treated with both 4PA and L-carnitine were increased, when compared to controls. The ratio of acylcarnitine to free carnitine excreted in urine in 4PA-treated rats was higher than that in either the control or 4PA plus L-carnitine group. The liver mitochondria in the 4PA plus L-carnitine group were the same as in the controls. The results suggested that the abnormal biochemical and morphological findings due to only 4PA may be relieved with L-carnitine supplementation.

Ammonia↗
PubMed1990

Carnitine metabolism and morphometric change of liver mitochondria in valproate-treated rats.

The effect of the administration for 7 or 28 days of 50 mg/kg/day valproate (VPA) on carnitine metabolism and morphological changes of liver mitochondria in immature rats was evaluated. The dose of VPA was almost the same as that we clinically used. Carnitine concentrations in serum, red blood cells (RBC), muscle, liver and urine were measured. The rats treated with VPA for 7 days showed no significant change in carnitine concentration in each tissue examined or by morphology. In the serum, RBC and muscle of rats treated with VPA for 28 days, free carnitine levels decreased, while acylcarnitine levels and the ratio of acylcarnitine to free carnitine (acyl/free ratio) increased. Mitochondrial enlargement was also induced and urinary acyl/free ratio of VPA treated rats was higher than that of control rats after the 14th day of the treatment. These results suggest that carnitine deficiency and morphometric changes in mitochondria occur time dependent even if the dose of VPA is clinically appropriate.

Animals↗
PubMed1990

Enhancement of polymorphonuclear leukocyte-mediated tumor cytotoxicity by serum factor(s).

It has been reported that beta-1,3-D-glucan isolated from Alcaligenes faecalis (TAK) promoted tumor cytolysis by mouse polymorphonuclear leukocytes (PMN). We investigated the effect of serum on mouse PMN tumor cytolysis induced by TAK and other PMN stimulators. Addition of fetal calf serum (FCS) to the cytolysis assay enhanced tumor cytolysis by PMN in a dose-dependent manner. Sera obtained from horses, mice, and rats were also effective enhancers of PMN tumor cytolysis. When FCS was added after the assay was under way, the enhancing effect decreased proportionally to the time elapsed. The enhancing activity was detected over a broad range of fractions with a peak at 170 kD by fractionation on a Superose 6 column. The responsible factor(s) in serum was stable after treatment at 60 degrees C, 30 min or after lowering the pH to 2. Mouse PMN stimulated with TAK increased production of hydrogen peroxide in the presence of FCS.

Alcaligenes↗
PubMed1990

The diagnosis of mild emphysema. Correlation of computed tomography and pathology scores.

Early and accurate diagnosis of emphysema is said to be invaluable for identification of clinically silent and mild emphysema. Recently, computed tomography (CT) has been much advocated for its efficacy in detailed diagnosis of emphysema, and the results have been compared with the pathology grade of emphysema in resected lung specimens. To assess the ability of high resolution CT scan in detecting and grading mild emphysema, we correlated the high resolution CT scan with the pathology grade of emphysema and the destructive index (DI) of lung specimens from 42 patients undergoing thoracotomy for a solitary pulmonary nodule. The high resolution CT scan and the cut surface of the lung, corresponding exactly to the same plane of the CT scan image, were assessed using the picture-grading system of Thurlbeck and coworkers on a scale of zero to 100. The CT scores for all patients ranged from 12 to 57, with a mean +/- SD of 22.1 +/- 9.6 using 1-mm collimation (n = 35), and from 7 to 46 with a mean +/- SD of 16.5 +/- 8.3 using 5-mm collimation (n = 33). The pathology scores ranged from 10 to 57, with a mean +/- SD of 23.2 +/- 9.8 (n = 42). The DI ranged from 15.4 to 67.1, with a mean +/- SD of 31.4 +/- 10.8 (n = 42). The CT scores using 1-mm and 5-mm collimation correlated significantly with the pathology scores (r = 0.68 and 0.76, respectively, p less than 0.001), and with the DI (r = 0.62 and 0.74, respectively, p less than 0.001). The pathology scores correlated significantly with the DI (r = 0.72, p less than 0.001). We therefore concluded that high resolution CT can help to identify the presence and grading of mild emphysema.

Adult↗
PubMed1990

[Membranous and respiratory bronchiole disease in patients with normal air-flow and mild air-flow limitation].

In order to evaluate the role of membranous (MB) and respiratory bronchioles (RB) in patients with normal and mild airflow limitation, we quantitatively assessed the pathological change of MB, RB and alveoli in the pathological specimens of 42 patients who required surgery for removal of a solitary pulmonary nodule. We also measured the destructive index (DI), to evaluate the destruction of alveolar walls. High resolution CT scan and pulmonary function tests were performed within 1 month of resection. Results of the pulmonary function tests correlated with pathological changes of RB better than with MB. Significant correlation between the emphysema score of resected lung and the pathological change of MB and RB was observed. There was also significant correlations between the CT score or DI and RB changes. However, there was no significant correlation between the CT score or DI and the change of MB. There were significant differences between smokers and nonsmokers in the results of pulmonary function test, pathological changes of RB and severity of emphysema. We postulate that RB is responsible for subtle functional abnormalities in the early stages of chronic obstructive pulmonary disease.

Adult↗
PubMed1989

[Comparison of intravenous drip infusion excretory urography using ionic and non-ionic contrast media].

Ionic and non-ionic contrast media were compared for use in intravenous drip infusion excretory urography. Sixty consecutive cases were classified alternately into two groups, ionic and non-ionic, excluding cases which were known to have factors affecting contrast ability adversely, such as hydronephrosis, renal failure and so on. Each group consisted of 30 cases. A hundred ml of the ionic contrast medium (Diatrizoate--60% Urografin) or non-ionic contrast medium (Iopamidol--Iopamiron 300) was administered I.V. by drip infusion, each infusion taking less than 10 minutes, using a 18 G needle, and 0-minute, 10-minute and 20-minute films were obtained. Visibility of nephrogram, calyceal system, renal pelvis, ureters and bladder were evaluated, ranging from 0 to 3, by six radiologists who were not informed of the contrast medium used. Some detailed factors such as radiographic contrast and fullness of the collecting system and of the bladder were also analyzed. Visualization rate of the ureters was defined as the length of visualized ureters divided by the distance between the renal pelvis and the ureteral orifice of the bladder. There was no significant difference in visualization of nephrogram between the two groups. However, the non-ionic group was superior to the ionic group in visualization of the calyceal system and ureters with statistical significance, probably due to higher radiographic contrast of non-ionic medium. There was no statistical significance between the two groups, in fullness of the calyceal system and visualization rate of the ureters, whereas the ionic group was superior to the non-ionic group in fullness of the bladder.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1989

Plasma sulfhydryl-containing amino acids in patients with cerebral infarction and in hypertensive subjects.

It has been postulated that an accumulation of a sulfhydryl-containing amino acid, homocysteine in plasma may induce arteriosclerosis. In order to explore a possible contribution of homocysteine to the development of cerebral infarction in middle-aged and elderly patients, plasma sulfhydryl-containing amino acid profiles of 45 patients with cerebral infarction (CI) were compared with those of 45 normotensive and 45 hypertensive controls, and 20 patients with cerebral bleeding (CB), of similar ages and sex. The concentrations of both free and total homocysteine in plasma were highest in patients with CI among the 4 groups, while plasma free and total cysteinylglycine levels were similar. Although both free and total cysteine levels were also higher in patients with CI than in normotensive controls, the total homocysteine/total cysteine ratio was highest in patients with CI among the four groups. The hypertensive controls had higher plasma free and total concentrations than normotensive controls, but the levels did not differ between the 21 normotensive and 24 hypertensive CI patients. Our results suggest that high levels of plasma homocysteine in conjunction with hypertension could be one of the risk factors for arteriosclerotic CI.

Adult↗
PubMed1989

Decreased blood flow and oxygen metabolism in the cerebellum, brain stem and thalamus in a case with Menkes kinky hair disease.

Cerebral blood flow and oxygen metabolism were measured in a five-year-old boy with atypical Menkes kinky hair disease (MKHD) by using positron emission tomography (PET). The patient was diagnosed as having atypical MKHD because of low serum and urinary copper levels, and clinical symptoms. The CT revealed mild to moderate degrees of brain atrophy predominantly in the cerebellum. The PET demonstrated marked decreases of cerebral blood flow and oxygen metabolism in the cerebellum, brain stem and thalamus. These findings seem to reflect the neuropathological abnormalities observed in MKHD. PET seems to be more sensitive than CT in detecting abnormalities in the affected structures. However, because this case is atypical the question of whether typical cases show similar features on the PET remains.

Brain Diseases, Metabolic↗
PubMed1989

[Comparison of high resolution computed tomography and pulmonary function tests in diagnosis of mild emphysema].

To assess the ability of high resolution CT scan and pulmonary function tests in detecting and grading mild emphysema, we correlated the high resolution CT scan and pulmonary function tests with the pathologic grade of emphysema and the destructive index of lung specimens from 42 patients undergoing thoracotomy for solitary pulmonary nodules. Using the high resolution CT scan, we could identify the pathologic grade of mild and moderate emphysema. By measuring diffusing capacity per unit alveolar gas volume (DLco/VA), it seemed to be possible to detect the mildest degree of alveolar destruction assessed by the destructive index, which was not detected by high resolution CT scan. The reason for these results seemed to be that we assessed the severity of emphysema by detecting the air space enlargement on high resolution CT scan images caused by the destruction of alveolar walls, which were detectable by measuring DLco/VA. We conclude that it is possible to detect mild emphysema using the combination of high resolution CT scan and pulmonary function tests.

Adult↗
PubMed1989

[Strengthening for dental porcelain surface].

UNLABELLED: Although the metal crown is aesthetically improved when porcelain is fused to it, a large number of different factors often cause the porcelain to break. Here we report a method to prevent this from happening. As a hardening treatment for the porcelain surface, the Na-ions in the porcelain, which have a short radius, were replaced by K-ions having a long radius to strength the surface against compressive forces. RESULTS: 1. The bending test showed that the strength of the porcelain had increased from 20 to 38%. 2. The hardness test indicated that the strength had increased from 23 to 24%. 3. The breaking test showed that although the strength of the porcelain had not increased to any great extent, the strength of the veneer shell had increase by more than 30%. 4. The EPMA measurement showed that ion replacement had penetrated to as much as 50 to 80 microns. 5. Clinical tests indicate that even after 19 months, the surface of the porcelain remains the same and that the condition is quite stable.

Dental Porcelain↗