Biomedical subjects
Publications and source records attributed to A Okada.
A very rare case of hepatoblastoma originating in the caudate lobe in an 18-month-old female infant is reported. Three years after surgical resection of the tumor, she is alive without signs of a recurrence.
Superoxide dismutase (SOD) activities in Parkinson's disease (PD) were significantly lower than those in controls, especially in a treated PD group. However, SOD activities in an untreated PD group did not decrease. There was a significant correlation between SOD activities and the duration of illness in the treated PD group (p < 0.05). There was a significant correlation between SOD activities and the present doses of L-DOPA/carbidopa in the treated PD group.
We present a case of Peutz-Jegher's syndrome in an 18 year old female who was followed for gastrointestinal polyps for 13 years from the age of 5 years. The patient was treated four times with surgical or endoscopic polypectomy for gastrointestinal polyps. At the age of 14 years, a combined surgical and endoscopic approach for the management of Peutz-Jegher's syndrome was carried out. A large polyp of the ileum required enterotomy for its removal, and another smaller polyp of the upper jejunum was identified and removed by intra-operative total enteroscopy via the anus. Intra-operative enteroscopy allows one to identify polyps that would previously have been missed. A more complete polypectomy can be performed using this technique, allowing the patient with Peutz-Jegher's syndrome a longer interval between laparotomies and a reduction in symptoms attributed to polyps.
A synchronous pulsatile venoarterial device for extracorporeal membrane oxygenation (ECMO) was designed to accomplish more effective circulatory support for neonates. The effect of this device was studied using an endotoxin-induced shock model, compared with conventional nonpulsatile ECMO. Twenty puppies weighing 1.6 to 4.0 kg were given endotoxin (5 mg/kg) intravenously. Thirty minutes after the administration of endotoxin, 10 were placed on pulsatile ECMO, and the others were placed on nonpulsatile ECMO, and they were studied for an additional 180 min. Peak blood pressure, arterial pH, base excess, and renal blood flow were significantly higher in the pulsatile group than in the nonpulsatile group. Serum lactate and serum noradrenaline were significantly lower in the pulsatile group than in the nonpulsatile group. These results indicate that pulsatile ECMO may provide more effective cardiopulmonary support in the treatment of neonates with serious circulatory failure that has failed to be supported by nonpulsatile ECMO.
We used the ELISA to measure the concentration of amyloid protein precursor with Kunitz type trypsin inhibitor domains (APPI) in CSF of dementia of the Alzheimer type (DAT) and examined the correlation of APPI with acetylcholinesterase (AChE) and somatostatin (SRIF). We found the APPI concentration in CSF of DAT to be significantly elevated compared with that of multi-infarct dementia and controls. We could significantly correlate APPI with AChE, but not correlate APPI with SRIF. The present results suggest that measurement of CSF APPI levels may be useful for diagnosis of DAT and the change of APPI may closely be associated with abnormality of acetylcholine system in DAT that has been reported.
In order to clarify the involvement of cerebral 3,4-dihydroxyphenylacetic acid (DOPAC) and vasoactive intestinal polypeptide (VIP) in whole-body vibration stress, DOPAC and VIP-like immunoreactivity (VIP-LI) in various discrete brain regions of rats exposed to whole-body vibration (4G, 20 Hz, 90 min) were assayed. The results showed that the whole-body vibration increased the DOPAC level in the frontal cortex and nucleus accumbens, but did not induce a concurrent change of VIP-LI in these regions. VIP-LI was significantly increased in the amygdala, and decreased in the hippocampus, accompanied by no significant change of DOPAC. These results show that whole-body vibration affects cerebral VIP neuron systems in addition to its nonspecific action, i.e. the activation of mesofrontal and mesoaccumbens dopamine neuron systems. It is assumed that the amygdalofugal VIP neuronal system is involved in the regulation of hypothalamic and pituitary hormone secretions, and that VIP in the hippocampus plays a part in modulating the blood circulation in the cortex in whole-body vibration stress.
Eight male Japanese Brazilians (20-32 yrs) and 11 male Japanese (22-24 yrs) volunteered for this study. The Brazilians had been staying for about 2-21 weeks in Japan. Their physical characteristics are not significantly different from those of the Japanese. Each one of them sat on a chair for 45 min at 40 degrees C (R.H. 50%) in a climatic chamber. Then, they exercised using a bicycle ergometer in a semi-reclining position for 45 min at 40% of maximal oxygen uptake. Forearm blood flow (FBF), oxygen uptake (VO2), heart rate (HR), skin temperature (Tsk), sweat rate (SR) at chest region and body weight loss (delta Wt) were measured. Thermal sensation and thermal comfort were also measured. Thermal and comfort sensation confirmed that Japanese Brazilians felt cooler and more comfortable in 40 degrees C environment than the Japanese. VO2, SR and delta Wt for both groups were not significantly different. FBF and HR for Brazilians were significantly lower than those for Japanese. Tsk at chest region for Brazilians was found to be significantly higher than that for Japanese. Thus the thermoregulatory responses observed in Japanese Brazilians may be largely attributed to the climate in their native places located on the Tropic of Capricorn.
Redistribution of zinc in tissues was induced during zinc-free TPN in PEM, and a marked decrease in skin zinc level may contribute to skin lesions and to impaired wound healing in skin. And clinical studies suggest that plasma zinc level is one of the sensitive markers for stress following surgery.
Three patients, i.e., two adults and one child, with unusual benign stricture of the extrahepatic biliary duct are reported. Case 1 is a 63-year-old male with obstructive jaundice caused by a sclerotic vascular ring formed by the right hepatic artery and its branch. Case 2 is an 18-year-old male with obstructive jaundice due to stricture of the common bile duct caused by compression of enlarged collateral varicose veins, so-called cavernous transformation following extrahepatic obstruction of the portal vein. Case 3 is a 19-month-old boy complicated with biliary obstruction resulting from ischemic changes of the biliary duct at 10 months after extended right hepatectomy for mesenchymal hamartoma of the liver. The definitive diagnosis was made on the basis of imaging evaluations and the surgical findings. They have been free of jaundice and have shown an uneventful clinical course after the surgical interventions.
A 9-year-old boy with a painless reducible swelling in the right groin was admitted to our hospital. The diagnosis of a right external inguinal hernia was made, but no inguinal hernial sac was found at operation. On further examination, the diagnosis of femoral hernia was confirmed. Radical operation for the femoral hernia was performed using McVay's procedure, and there has been no recurrence since the operation. In the Japanese literature, 25 cases of femoral hernias have been reported in children aged 1 month-9 year (average age, 4 years). The sex ratio of M:F was 2:3. Eleven cases were on the right side, 7 were on the left, and 5 were bilateral. The rate of irreducible femoral hernia was 48% (12/25 cases). Femoral hernias in children are very rare and often misdiagnosed as inguinal hernias. Correct diagnosis was made in only three cases (12%). Careful examination and awareness of the possibility of femoral hernia in children are very important when dealing with groin swelling in children.
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This study was designed to investigate whether a combination of a glutamine antagonist (DON) and a diet deficient in glutamate and aspartate (AG) altered glutamine metabolism in tumor tissue, and inhibited tumor growth. In experiment-1, 21 male Donryu rats were fed with AG and implanted with Yoshida's Sarcoma. Of them, 7 rats were sacrificed on the 5th day (group AG), other 7 were sacrificed next day (group AG-1) and the remaining 7 were injected with DON on the 5th day and sacrificed next day (group AG+D). The tumor weight of group AG+D was significantly lower than of group AG, or of group AG-1. In experiment-2, of 23 rats, 9 were fed with control diet and 14 were fed with AG and implanted. 12 were sacrificed on the 5th day (group C, AG), and 11 were injected with DON on the 5th day and sacrificed next day (group C+D, AG+D). The reduced ratio of tumor weight in group C+D and group AG+D were 25% and 67%, respectively. These results show that the tumor growth could be inhibited by using metabolic antagonist of glutamine, and that it had synergistic effect in conjunction with the imbalanced diet.
We compared two types of biliary reconstruction for congenital dilatation of the bile duct--Roux-en-Y hepaticojejunostomy and jejunal interposition hepaticoduodenostomy after removal of the dilated bile duct. There were no significant differences in the occurrence of early and late complications except for the repeated attacks of abdominal pain that occurred only in the group that underwent jejunal interposition hepaticoduodenostomy. The results of further examinations for the presence of bile reflux with 99mTc-pyridoxyl methyl tryptophan scintigraphy and gastroscopy in this group revealed a high incidence of chronic gastritis associated with bile reflux. This report is the first to demonstrate the occurrence of bile reflux gastritis in patients who underwent jejunal interposition hepaticoduodenostomy, which is theoretically a more logical approach than the other method of bile reconstruction. Further studies, with respect to possible mechanisms, as well as careful and longer follow-up evaluation, are required.
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Multi-unit sympathetic activity was recorded at elbow level from median nerve fascicles supplying glabrous skin of the left hand in five healthy subjects. The resultant vasomotor responses accompanying the neural activity were monitored by simultaneous recordings of skin blood flow using the laser doppler method and skin temperature in the innervation zones. No significant change in sympathetic activity was observed during handgrip exercise of the right hand under a constant gripping force of 2 kg. Subjects maintained the same gripping force of the right hand during exposure in random order to local vibration and/or noise, each type of exposure lasting 5 min with intervals of 20 min. A two-peaked significant increase in outflow from sympathetic nerves was observed during local exposure of the right hand to vibration with a frequency of 60 Hz and an acceleration of 50 m.s-2, followed by a postexposure period which revealed a relative suppression of sympathetic nerve activity and a significant increase in blood flow. Noise at 100 dB(A) showed only an initial effect on skin sympathetic nerve activity (SSA), whereas when combined with local vibration at 60 Hz, a pronounced increase in neural activity was noticed, indicating a combined effect of vibration and noise. These results from direct recordings of SSA suggest a sympathetic vasomotor reflex mechanism triggered by local vibration stimuli to the hand.
A 21-year-old man with childhood-onset mental retardation, non-obstructive hypertrophic cardiomyopathy, and vacuolar myopathy is presented. A histopathological study of biopsied skeletal muscle showed lysosomal glycogen storage mimicking acid maltase deficiency, but biochemical analysis showed normal acid alpha-glucosidase activity. Glycogenosomes were also recognized in endothelial cells on electronmicroscopic examination of biopsied skeletal muscle. Magnetic resonance imaging (MRI) findings in the head revealed the involvement of the central nervous system. This is a new type of lysosomal glycogen storage disease with multisystemic involvement. The specific biochemical defect in this disorder remains to be elucidated.
To investigate the effects of whole-body microwave exposure on plasma adrenocorticotropic hormone (ACTH), thyroid-stimulating hormone (TSH), thyroxine (T4) and free triiodothyronine (T3) levels, rats weighing 267-306 g (light group) and 352-387 g (heavy group) were exposed to microwaves with a frequency of 2,450 MHz at the power densities of 5 and 10 mW/cm2 under an ambient temperature of 21 degrees C to 23 degrees C for an hour. Rectal temperatures were increased by 1.0 degrees C at 5 mW/cm2 and 2.1 degrees C at 10 mW/cm2 in the light group, and by 0.7 degrees C at 5 mW/cm2 and 1.5 degrees C at 10 mW/cm2 in the heavy group after microwave exposure. Plasma levels of ACTH increased significantly at 10 mW/cm2 in the light group and 5 and 10 mW/cm2 in the heavy group after microwave exposure. Plasma levels of TSH increased significantly at 10 mW/cm2 only in the light group. As for plasma levels of free T3, a significant decrease at 10 mW/cm2 was observed only in the heavy group. However, plasma levels of T4 did not change in either group after microwave exposure.
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