Biomedical subjects
Publications and source records attributed to S Miyazaki.
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Clinical studies were made of 60 patients who had undergone ureterosigmoidostomy at our department. The 45 men and 15 women ranged from 35 to 73 years old, with a mean of 59.2 years. Ureterosigmoidanastomosis was performed using the modified Coffey II technique in this series. Bladder tumor was the reason for the operation in 55 cases, uterine cancer in 2, contracted bladder in 1, vesicovaginal fistula in 1 and urethral stricture in 1. In the excretory pyelogram one month after the operation, normal findings and slight hydronephrosis were observed in 37% and 63% of the patients, respectively. However, the pyelogram 6 months after the operation demonstrated normal findings in 61% of the patients, slight hydronephrosis in 34% and moderate hydronephrosis in 5%. None of them showed severe hydronephrosis. Slightly increased BUN level (less than 30 mg/dl) was seen in 15 out of 45 patients (32%) at one year after ureterosigmoidostomy. However, serum creatinine level was not above normal throughout the postoperative course. Although postoperative hyperchloremia was appreciably detected, it was easily managed by the administration of sodium bicarbonate. Serum sodium and potassium levels remained stationary. Of 35 patients observed for more than one year after operation, 11 patients (31%) had developed fever due probably to pyelonephritis, but sigmoidography failed to demonstrate any ureteral reflux. Either urinary or fecal fistula, a complication in the early postoperative period, occurred in 10 patients (17%). One of these patients died. Five patients were cured by conservative treatment. The remaining 4 patients underwent surgical treatment that was ureterocutaneostomy , nephrectomy, or colostomy.(ABSTRACT TRUNCATED AT 250 WORDS)
Twenty-two patients underwent surveillance colonoscopy for 2 to 54 months (average, 22 months) after ureterosigmoidostomy. The distance between site of ureterocolonic anastomosis and anal verge ranged from 13 to 30 cm (average, 18.3 cm) in right side and from 20 to 37 cm (average, 29.5 cm) in left side. The form of implanted site could be classified into 3 types which were flat, sessile and pedunculated types. Endoscopic biopsies performed on eleven polyp-like regions of ureterocolonic anastomosis revealed inflammation in 10 cases (90%) and adenoma without malignancy in one case (10%). The mucosa more than 5 cm away from implanted site showed findings of inflammation without constitutional abnormality in more than 60% of all patients. The periodical surveillance colonoscopy at intervals of approximately one year seemed to be useful for early detection of the tumors of the colon after ureterosigmoidostomy.
A heated casein-histidine mixture, or the model compound of gizzard erosion-inducing fish meal, was prepared, and a gizzard erosion-inducing substance in this mixture was partially purified. The mixture was refluxed with hydrochloric acid, and the supernatant was obtained. The supernatant was then adjusted to the pH of the isoelectric point of casein and the resulting precipitate collected. The precipitate was further hydrolyzed with papain at a neutral pH. After acidification of the reaction mixture, the supernatant and the precipitate were separated. The supernatant fraction, which was toxic to induce gizzard erosion, was submitted to a gel filtration of Sephadex G-25, and resolved into five fractions. Gizzard erosion-inducing toxicity was found only in the second fraction. The non-toxic second fraction was also prepared by the same treatment from the non-toxic material of heated casein. The characters of these toxic and non-toxic second fractions were compared by using several analytical methods. Thin layer chromatography, as well as gel permeation chromatography, revealed that more than eight components having widely distributed molecular weights existed in both second fractions. By reversed phase chromatography, these fractions were found to consist of various peptides (or peptide-like compounds). Some characterizations, however, were performed. It failed to detect any difference in the components between the toxic and non-toxic second fractions by any analytical method used.
Whole meal produced from fresh sardine had a high content of histidine, while that from rancid fish had a high content of histamine. The toxicity to induce gizzard erosion, which appeared after heating, was stronger in the former whole meal than in the latter. Thus, the content of histidine, not that of histamine, was well correlate to the degree of toxicity of the heated fish meal. Changes in the contents of histidine and histamine were also studied in model compounds during heating.
Patients with unresectable liver cancer (primary and metastatic) were treated with a newly-devised arterial infusion chemotherapy using Cis-DDP and its antidote Sodium thiosulfate (STS). The patients consisted of 4 with primary hepatoma and 1 with metastatic liver cancer originated from intestinal cancer. For the purpose of reducing unfavourable side effects without changing anticancer effect, Cis-DDP was infused into hepatic artery through the catheter while STS being administered systemically. According to Koyama and Saito's criteria, 2 of 5 patients showed partial response (PR) and the others showed no change (NC). The median survival time after onset of therapy was 6.6 months ranging from 2 to 11 months in all the patients. The myelosuppression and renal toxicity, which were considered to be the most serious side effects of Cis-DDP, were not found and liver function was not affected in all the patients. However, all the patients complained of nausea and vomiting. Thus, our experience has indicated that this newly devised infusion chemotherapy is a promising method for treating unresectable liver cancer, although further efforts are necessary for reducing the gastrointestinal toxicity.
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Electroclinical features of convulsive apnea and its relation to the behavioral state were described on the basis of polygraphic recordings from 21 newborns with various underlying disorders, including perinatal anoxia, purulent meningitis, and intracranial bleeding. The most frequent ictal discharges were rhythmic alpha waves, but other types of discharges, such as repeated sharp waves, rhythmic theta waves, delta waves, and repeated paroxysmal wave complexes, were also frequently seen. The area where the ictal discharges initially occurred or were most prominent was the temporal area, suggesting the limbic origin of apneic seizures. In more than half of the cases, the sleep cycle was abolished. In those cases where the sleep cycle was preserved, the seizures occurred most frequently in active sleep, but never in quiet sleep.
Utilizing lymphocyte proliferation assay, effects of operation on cell-mediated immune response to autologous tumor extract were studied in 33 patients with gastric or colon carcinoma. To evaluate the lymphocyte proliferation response to autologous tissue extract preoperatively, the lymphocytes were left in culture for 24-30 hours before addition of the extract while 3 M KCl extract of autologous tissue was being processed. A significant level (P less than 0.001) of correlation was observed between stimulation index values to autologous tumor extract added at the initiation of culture and after a 24-30-hour period of incubation. Using this type of assay system, lymphocyte proliferation response to autologous tumor extract was examined immediately before operation and 1, 2, and 4 weeks after operation serially. Data comparing the responses of 20 patients who had curative resection and 13 patients who underwent noncurative resection appeared to fall into three categories in each group. The clinical courses of these patients in each category might clarify the significance of changes in the response following operation.
Neonatal findings and evolutionary courses of epileptic seizures were described in newborns who had seizures during the neonatal period and later developed epilepsy. Neonates with CNS dysgenesis ran the highest risk (80%) for subsequent epilepsy. About 30% of those who suffered from perinatal hypoxia and/or intracranial birth injury and 30% of those who had meningitis developed subsequent epilepsy. In perinatal brain injury, those who developed epilepsy showed more abnormal neurological and electroencephalographic findings than those who did not. The more abnormal the neonatal background EEG, the more frequently epileptic fits developed later. There was no such relationship in CNS dysgenesis. Myoclonic seizures were associated with the most severe brain damage. Newborns who later displayed West syndrome had also very abnormal neonatal EEG whereas those who manifested other types of fits more often had less abnormal neonatal EEGs. In West syndrome, hypsarrhythmia was preceded by focal or multifocal spikes, and closely temporally related with the onset of spasms, but there was a variety of intervals between the onset of clinical fits and EEG spikes in generalized or focal motor seizures.
Sleep and body movements were studied in 2 hydranencephalic neonates using visual analysis and polygraphic recording. They manifested periodic alternation of active and quiet sleep with peculiar movements of bilateral synchronized patterns. Generalized phasic movements were significantly increased and localized tonic movements were reduced. In view of the complete absence of cerebral hemisphere in this disorder, the movement of bilaterally synchronized pattern or increase of generalized phasic movement are considered to be generated from the basal ganglia and/or brain stem without cerebral hemisphere, whereas, localized tonic movements have more cortical correlation in its organization. The observation of body movements may be useful in detecting hydranencephaly in early infancy.
Body movements during sleep were observed in 14 full-term sick newborn infants such as perinatal asphyxia, purulent meningitis, meconium aspiration syndrome, melena, porencephaly, and hydranencephaly. Five newborn infants who had recovered from transient vomiting were examined as control. Infants with minimally depressed background EEG showed an increase of generalized movement (GM) and localized tonic movement (LTM) in quiet sleep. Hydranencephalic infants revealed an increase of generalized phasic movement (GPM) in active and quiet sleep. On the other hand, a decrease or an absence of body movements was observed in infants with severe EEG abnormalities such as moderate, marked and maximal depression. Hydranencephalic and porencephalic neonates showed a decrease of LTM in active sleep. One infant with purulent meningitis, showing markedly depressed EEG, revealed GPM-like movements of much longer duration. The follow-up study revealed that the absence of body movements or the increase of GPM might indicate a very poor outcome, whereas the presence of LTM, even in a small amount, suggested the preservation of cortical functions. The increase of body movements was also considered to correlate with sleep disturbance and served to indicate a brain dysfunction.
The EEG, sleep cycle, visual and auditory evoked potentials (VEP and AEP) were studied in 38 newborns who presented with seizures and had serum calcium levels below 7 mg/dl. Nineteen infants displayed increased theta and alpha, and decreased delta waves with variable but mild degrees of background EEG depression during sleep, which may reflect neuronal hyperexcitability induced by hypocalcemia. Hypocalcemic infants spent less time in quite sleep than control infants, but the time spent in active sleep did not change significantly. Seventy-seven percent of seizures occurred in active sleep. 17% in indeterminate sleep and 1% during wakefulness. Most infants demonstrated normal VEP and AEP, although a few displayed prolonged latency. No correlation was found between peak latency and serum calcium levels. Two infants with complicated hypocalcemia who showed moderately depressed background EEG and other two with loss of sleep cycles developed abnormally, while the other infants showed normal development.
Golden hamster eggs respond to fertilization with recurring hyperpolarizations [Miyazaki, S. & Igusa, Y. (1981) Nature (London) 290, 703-705]. We analyzed the ionic mechanism of the fertilization potential and examined whether the fertilization potential plays a role in polyspermy block. Each hyperpolarizing response (HR) during fertilization is found to be caused by an increase in the K conductance activated by an increase in the intracellular Ca2+ concentration. This conclusion is based on the following: (i) The reversal potential of the HR shifted with the Nernstian slope for K ions when the external K concentration was changed, whereas it was unaltered by the removal of Cl ions. (ii) The HR was blocked by the intracellular injection of EGTA. (iii) Injection of Ca2+ into an egg induced a hyperpolarization of the membrane similar to the HR. The Ca-activated K conductance shows an apparent outward rectification, which could be explained by an asymmetric distribution of K ions across the membrane. The HR associated with sperm entry into the egg occurred at any membrane potential between -160 and +50 mV. Therefore, a potential-dependent block of sperm entry does not occur in the hamster egg.
1. The effect of acetylcholine (ACh) on the rat adrenal chromaffin cell membrane was examined in culture by using an intracellular recording technique. ACh was applied with gas pressure through a pipette which had an internal tip diameter of about 3 mum.2. Upon application of ACh the chromaffin cell membrane depolarized with superimposed potential fluctuations. Occasionally repetitive spikes were observed during the entire period of ACh application up to 30 sec. In some cells a hyperpolarization with a slow time course followed the initial depolarization.3. The depolarization was detectable with 0.1 mum-ACh; the amplitude increased with higher concentrations of ACh and saturated at 100 mum. The half-maximal concentration was approximately 10 mum.4. The amplitude of the ACh depolarization increased when the membrane was hyperpolarized by passing current through the recording electrode, and decreased upon depolarization. This technique gave an apparent reversal potential of -24+/-4 mV (mean+/-S.D., n = 6).5. When the mean amplitude of the ACh depolarizations and the variance of the potential fluctuations in a given cell were plotted, a linear relation was found. The slope was 0.23+/-0.06 mV (n = 9) at the average membrane potential level of -60 mV. With a few assumptions this value approximates the amplitude of an elementary potential change.6. Temporal characteristics of the potential fluctuations were obtained by calculating an auto-correlation function. The averaged auto-correlation function in a given cell declined exponentially with time. The mean time constant at 31 degrees C was found to be 40+/-19 msec (n = 9) at the average membrane potential level of -60 mV. With a few assumptions this value provides an estimate of the mean duration of an elementary potential change.7. The ionic mechanism of the ACh depolarization was examined by changing the ion composition of the external solution. Na, K and Ca ions appear to be the current carriers during the ACh depolarization; Cl ions do not contribute.8. Various ACh receptor agonists and antagonists were applied to determine the pharmacological properties of these ACh receptors. The receptors were found to be nicotinic.9. The nature of the ACh-induced membrane potential fluctuations is discussed.