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M Segawa

Publications and source records attributed to M Segawa.

At least 19 recordsLinked to original sources
PubMed1992

[Measurement IGF-I in human blood by immunoenzymometric assay].

Insulin-like growth factor-I (IGF-I) is the growth factor which binds to its specific binding proteins in plasma and mediates most of the actions of growth hormone (GH). In terms of this, measurement of IGF-I concentrations is considered to be important in the diagnosis and treatment of growth abnormalities. In the present report we describe a modified immunoenzymometric assay (IEMA) for IGF-I using monoclonal antibody and peroxidase conjugated polyclonal antibody, which was originally developed by Tamura et al. The minimum detection level was 3ng/ml and good linearity was obtained at a range of 3-50ng/ml. The recovery of added IGF-I was nearly quantitative, and cross reaction with human IGF-II was less than 1%. There was a significant positive correlation between the IGF-I values determined by IEMA and by RIA. We measured the levels of IGF-I by this IEMA in normal subjects and children with short stature. Serum or plasma samples were extracted by acid-ethanol method. In normal children IGF-I level was observed age-dependently. IGF-I values gradually increased and reached peak levels (101.2-473.2ng/ml) in pubertal period and thereafter decreased to adult levels (67.3-329.6ng/ml). In subjects with short stature older than 5 yrs, the percentages falling below the normal mean for chronological age by at least 2SD were 100% for complete GH deficiency (n = 5), 80.0% for partial GH deficiency (n = 15), 25.0% for GH neurosecretory dysfunction (n = 4), 40.0% for non-endocrine short stature (n = 60) and 25.0% for Turner syndrome (n = 4). In children younger than 4 yrs, it may be difficult to use IGF-I for diagnosis of GH deficiency because there was an overlap in IGF-I values with normal children. IEMA for IGF-I is shown to be a reliable method for measurement of IGF-I in blood and is appropriate for diagnosis of growth disorders with short stature in subjects older than 5 yrs.

Adolescent↗
PubMed1992

Initial hepatic metabolic function in canine liver and pancreas cluster transplantation.

In this study, initial hepatic metabolic function was evaluated by determining the arterial ketone body ratio (AKBR) and plasma amino acid concentrations in an experimental orthotopic combined hepatopancreatic transplantation (OHPT), and comparing the same values in orthotopic liver transplantation (OLT). In OHPT, AKBR decreased in the anhepatic phase and recovered to the preoperative value just 1 h after reperfusion. On the other hand, in OLT, the recovery of AKBR took 3 h after reperfusion with a significant difference compared to OHPT (P less than 0.05). Plasma amino acid levels, especially alanine and total free plasma amino acids increased in the anhepatic phase and recovered within 1 h of reperfusion in OHPT. However, they did not recover until 3 h after reperfusion in OLT. This rapid recovery of hepatic metabolic function in OHPT should be attributed to the order of reperfusion in which the reconstruction of arterial blood flow precedes that of portal blood flow. This model is useful for assessing the best way by which the grafted liver can for assessing the best way by which the grafted liver can control the timing, order, rate, and volume of blood that should be released.

Amino Acids↗
PubMed1992

Focal nodular hyperplasia of the liver.

We present herein two successfully treated cases of focal nodular hyperplasia (FNH) of the liver, a relatively rare disease. Case 1 was a 3 year old child in whom typical FNH developed in the left lateral segment of the liver, whereas Case 2 was a 22 year old man in whom characteristic findings were lacking on preoperative diagnostic imaging. Scintigraphy was not performed in either case, however, postoperative histological examination confirmed FNH. Thus, in patients with a hypervascular tumor and normal liver function, FNH should be strongly suspected and a series of scintigraphy proposed. Both cases showed a negative association with oral contraceptive intake but no other obvious etiology was suggested.

Adult↗
PubMed1992

Interaction between heat acclimation and exogenous insulin in brown adipose tissue of rats.

Seventy-one male Wistar strain rats (7 weeks old) were kept at 5, 25, or 34 degrees C, respectively, for 2 weeks with or without insulin administration. Insulin (Novo Lente MC) was given subcutaneously in a dose of 3.62 nmol/125 microliters saline per 100 g body weight. An apparent effect of insulin treatment was noted only in heat-exposed rats, resulting in a remarkable gain in interscapular brown adipose tissue (BAT) mass of heat-acclimated, insulin-treated rats in terms of weight or weight per unit body weight. The BAT from heat-acclimated, insulin-treated rats had significantly higher levels of protein, DNA, RNA, and triglyceride than BAT from heat-acclimated, saline-treated rats. Therefore, it seems likely that the growth of BAT in heat-acclimated, insulin-treated rats was mostly due to the anabolic effects of insulin. The uncoupling protein mRNA was, however, present in BAT of heat-acclimated, insulin-treated rats at rather a depressed level, explaining a corresponding decrease in cold tolerance. On the other hand, the expression of insulin receptor mRNA was attenuated in BAT of rats from all the insulin-treated groups, possibly due to the down-regulation of insulin. Thus, there appeared to be some linkage among BAT, heat acclimation, and insulin.

Acclimatization↗
PubMed1992

[PMUE therapy (CDDP, MMC, UFT, etoposide) for advanced gastric cancer--a case report].

CDDP, MMC, UFT and Etoposide (PMUE)-combined therapy was given to a 62-year-old man with advanced gastric carcinoma. PMUE therapy consists of i.v. injection of CDDP 75 mg/m2 and MMC 10 mg/body on day 1, i.v. injection of Etoposide 50 mg/body on days 3, 4 and 5 and consecutive daily administration of UFT 400 mg/body, with 3 weeks as one course. He was admitted for Borrmann type 3 gastric carcinoma with multiple liver metastasis, lymph node metastases and peritoneal dissemination, the underwent total gastrectomy with R2 lymph node dissection. He was treated four times with this therapy after sensitivity test for carcinostatic agents (SDI test), which resulted in complete remission, as confirmed by CT scan and second-look operation. The patient has currently been free of disease, and we conclude that this PMUE therapy is extremely effective for advanced gastric carcinoma.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1992

[An electron microscopic study on osteoblastoma--ultrastructure and fine localization of alkaline phosphatase].

Three cases of osteoblastoma were studied by electron microscopy. They included two cases of conventional osteoblastoma and one case of aggressive osteoblastoma. In conventional osteoblastoma, ultrastructural features and location of alkaline phosphatase activity of the osteoblast-like cell were similar to those of normal osteoblast. On the other hand, aggressive osteoblastoma cell (case 3) showed different structure from those of a normal osteoblast; the nucleus of the tumor cell showed irregular surface with a small degree of heterochromatin, and poorly developed cytoplasmic organellae. Cytochemically, alkaline phosphatase activity was noted not only on the cytoplasmic membrane, but on the abundant vesicles in the cytoplasm. From these findings we conclude that the aggressive osteoblastoma cells are more immature in morphology and show increased synthesis of alkaline phosphatase.

Adolescent↗
PubMed1992

Motor symptoms of the Rett syndrome: abnormal muscle tone, posture, locomotion and stereotyped movement.

Amongst the motor, mental, cognitive and emotional symptoms of the Rett syndrome (RS) the motor symptoms stand out as the hallmark in analyzing the essential pathophysiology. Summarizing the motor symptoms and searching into the knowledge of relevant basic sciences, this report aims at stressing the pathophysiological basis of RS which we have reported in previous studies. The core motor symptoms of RS consist of two aspects; firstly the unique developmental abnormalities of the discrepancy of crawling and walking and secondly the pathognomonic symptoms which include the abnormal muscle tone, posture, locomotion and stereotyped movement. The deranged crawling reflects the abnormal locomotive function. The primary responsible neuronal structures of the abnormal muscle tone, posture and locomotion are probably in the brainstem. Aberrantly formed neuronal structures responsible for voluntary movements and modulatory factors from the basal ganglia are the pathophysiological basis of the stereotyped movement of RS. Thus the neuronal structures that underlie the clinical characteristics of RS extend broadly from the motor neurons to the higher cortex, but involve the specific neuronal systems. The most important and primary of these specific neuronal systems are thought to be the monoaminergic systems, originating from the brainstem and midbrain. Abnormally deficient noradrenergic, serotonergic and dopaminergic systems result in the abnormal modulation of ontogeny and function of the higher and lower nervous systems. As we have already stressed, this unique putative pathophysiological basis could explain the very striking set of clinical symptoms of RS and their age dependent appearance despite the lack of major specific findings in neuropathology.

Female↗
PubMed1992

Middle and short latency somatosensory evoked potentials (SEPm, SEPs) in the Rett syndrome: chronological changes of cortical and subcortical involvements.

Middle and short latency somatosensory evoked potentials (SEPm, SEPs) were studied in 11 cases of the Rett syndrome (RS) to detect the chronological changes of cortical and subcortical involvements. The cortical N1 (18) latency was significantly delayed in cases above the age of 5 years. Subcortical components up to N16 which are considered to be derived from the thalamus or the upper brainstem were mostly normal in cases under 9 years of age. However, in those over 9 years, the brainstem component P14 and the cervical cord component N13 revealed a delay in latency. The clavicular component N9 and component N11, which is considered to be from the spinal cord entry, were still normal in our cases. These findings suggested that before the age of 9 years, the revealed lesion in SEP is mainly rostral to the thalamus or upper brainstem. With increasing age and disease process, the involvement of the lower brainstem and the spinal cord becomes apparent. Thus, a degenerative process might be suspected. However, the chronological changes of N1 (18) and N13 parallel to normal development seen in RS indicated that the maturational changes were found up to around the age of 5-6 years in the former and 9 years in the latter, though the mean values of these two peak latencies were slightly higher than those in controls as early as the age of 3-4 years. These observations also indicated developmental, probably metabolic, abnormality underlies the pathogenesis of RS and the degenerative process might overlay in the later period of the disease.

Adolescent↗
PubMed1992

Polysomnography in the Rett syndrome.

The features of sleep parameters in the Rett syndrome were compared with those in early infantile autism (EIA) and hereditary progressive dystonia with marked diurnal fluctuation (HPD). The sleep-wakefulness cycle and the tonic and phasic components of sleep were evaluated in each disorder, the former was estimated by the day-by-day plot method and the latter two by polysomnography (PSG) following our method. Abnormalities of the sleep-wakefulness cycle were observed in the Rett syndrome and EIA, but in the latter these abnormalities became inapparent with age and improved markedly by correcting the environmental condition and completely by 5-hydroxytriptophan. The latter, if treated early, was followed by improvement of behavior. In the Rett syndrome, however, the abnormalities continued into late childhood to adolescence. In HPD, PSG abnormalities were restricted to the phasic component, which improved completely after levodopa in accordance with the clinical improvement. On the other hand, in the Rett syndrome as well as in EIA both the phasic and tonic components were involved and also the leakage of the components of REM stage into NREM stage was observed. In the Rett syndrome, these abnormalities aggravated with age, with disturbances in % sleep stage, nocturnal variation of tonic and phasic components of sleep and REM-NREM cycles, while in EIA the results of PSGs revealed no such progressions but showed an increase in twitch movement and a lack of normal increase in the number of REMs occurring in short intervals.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1991

Evaluation of initial hepatic allograft function with changes of free plasma amino acids in canine orthotopic liver transplantation.

We investigated the correlation between amino acid level and hepatic graft function. Plasma amino acid levels were measured at three time periods during canine orthotopic liver transplantation. During the anhepatic phase, plasma amino acid levels rose except for tryptophan. Cystine and alanine (Ala) increased significantly to 210 +/- 28% (n = 20, mean +/- SEM) and 203 +/- 11% from preoperative values (100%), respectively. In animals successfully surviving without hepatic insufficiency after transplantation of fresh livers (n = 7), plasma amino acid levels were restored to preoperative values within 3 hr following reperfusion. On the other hand, in animals that died from hepatic insufficiency within 5 days after grafting of warm ischemically damaged livers (n = 8), plasma amino acids, especially Ala, phenylalanine, total free plasma amino acids, and aromatic amino acids progressively increased to 216 +/- 25, 274 +/- 36, 152 +/- 15, and 152 +/- 15% at 3 hr after reperfusion. These were significantly higher compared to those of the group of animals transplanted with fresh livers (P less than 0.01-0.05). Furthermore, higher values were found in those dogs transplanted with warm ischemically damaged livers surviving for shorter periods. Also in dogs that died from hepatic insufficiency within 8 hr after grafting of livers preserved for 24 hr (n = 5), amino acid levels were at high values at 3 hr. These results suggest that in animals having good graft function, plasma amino acid levels are restored to preoperative values by 3 hr after reperfusion. In other cases, primary nonfunction should be strongly suspected after liver transplantation.

Amino Acids↗
PubMed1991

Roles of a subependymal nodule of tuberous sclerosis on pathophysiology of epilepsy.

Polysomnographies (PSG) were performed on two cases with tuberous sclerosis (TS), both having subependymal nodules on the medial wall of the caudate nucleus adjacent to the thalamostriatal sulci. Clinically one had suffered from infantile spasm and which later turned out to be complex partial seizure with a rotation toward the right. The other had developed tonic seizure on the right with a rotation toward the left in early childhood. Clinico-pharmacological studies revealed the existence of synaptic supersensitivity of the dopamine (DA) receptor in the left caudate and PSG confirmed the synaptic supersensitivity of the former, while in the latter case, it suggested a decrease in DA activity on the left. Subependymal nodules in the caudate nucleus could cause a reduction in the DA transmission and develops synaptic supersensitivity after suffering from TS.

Adolescent↗
PubMed1991

The development of sleep and wakefulness cycle in early infancy and its relationship to feeding habit.

The purpose of this study was to evaluate the relationship between sleep and wakefulness patterns to feeding habits in early infancy. The population consisted of 33 neurologically normal infants studied during their first 4 months of life. The number of 30-min epochs with sleep (sleep epoch) were counted in each 4-hr period in a day and evaluated over time. The effects of feeding on sleep and wakefulness were examined by analyzing the rates of sleep epoch after feeding in each time period. The rates of sleep epochs in each time period showed specific patterns each week. From 2 weeks of age, sleep epochs appeared most frequently in time periods 0:00-4:00 and 4:00-8:00 (p less than 0.01). These periods also had significantly high rates of sleep epochs after feeding by week 2. From week 6 both the number of sleep epochs and the rate of sleep epochs after feeding in time periods from 8:00 to 20:00 tended to decrease. These results suggest that the development of the circadian oscillation is set as a sleep epoch first during the time period of 0:00 to 8:00. In addition, feeding alone seemed to have no role as a time cue in the first 4 months of life.

Circadian Rhythm↗