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Biomedical subjects

M Nishijima

Publications and source records attributed to M Nishijima.

At least 199 records · Page 11Linked to original sources
PubMed1990

[Effect of maternal oxygenation on fetal blood gas status in shiba goat fetuses].

The purpose of this study is to investigate the effect of maternal oxygen administration on the fetal blood gas status. Five Shiba goat fetuses were used whose gestational days were 134 +/- 4 days. Maternal and fetal pH, pO2, pCO2, B.E., and hematocrit were measured every 30 minutes during 4 l/min oxygen administration for 60 minutes. Maternal arterial blood pO2 increased from 95.5 +/- 19.6 mmHg to 262.6 +/- 75.8 mmHg at 30 minutes and to 207.8 +/- 110.1 mmHg at 60 minutes. Fetal arterial blood pO2 increased significantly from 18.4 +/- 3.0 mmHg to 24.4 +/- 5.8 mmHg and 23.6 +/- 6.9 mmHg, respectively. There was a significant positive correlation between maternal pO2 and fetal pO2. The increase in fetal pO2 was small when the control pO2 was less than 17 mmHg. Although maternal pH did not change significantly, fetal pH decreased significantly from 7.29 +/- 0.07 to 7.25 +/- 0.07 at 60 minutes. Also fetal hematocrit decreased significantly from 33.9 +/- 5.2% to 32.8 +/- 5.4% at 60 minutes. Neither maternal nor fetal pCO2 and B.E. changed significantly. Therefore, we concluded that the effect of maternal oxygen administration on fetal pO2 was small when the fetus was already hypoxic. Also 60 minutes' oxygen administration may cause the decrease in fetal pH and hemodilution.

Animals↗
PubMed1990

[Acoustic neurinoma in a child].

A case is reported of acoustic neurinoma unrelated to Von Recklinghausens' disease in a child. A 14-year-old boy had suddenly become aware of impaired hearing associated with tinnitus, in August, 1988. He was admitted to our department in October, 1988. On admission, he had no neurological deficits except for right tinnitus. Acoustic tumor was found on air CT and MRI. Total removal of the tumor was achieved through a suboccipital craniotomy. The tumor had originated in the superior vestibular nerve. The size of the tumor was about 1 X 2 cm. The histological diagnosis was neurinoma. The facial and cochlear nerves were anatomically preserved. Twenty-two reported cases of acoustic neurinoma in children less than 15 years of age were reviewed. Based on these reports, it was concluded that acoustic neurinoma may grow rapidly in children, and they should be diagnosed and treated at an early stage.

Adolescent↗
PubMed1990

[Tryptophan metabolism during the perinatal period].

UNLABELLED: Tryptophan is considered to be an important indicator of nutritional changes during the perinatal period, from fetus to neonate. By means of high performance liquid chromatography (HPLC), we determined the concentrations of both free tryptophan (TRP) and its metabolite, kynurenine (KYN), in maternal venous plasma (M.V.) and umbilical arterial and venous plasma (U.A., U.V.) (n = 45) at the time of delivery. TRP and KYN concentrations were also measured in neonatal venous plasma (n = 11) for 3-5 days following delivery. RESULTS: 1) Day and night plasma TRP levels in non-pregnant women (n = 12), in pregnant women at term before labor (n = 12) and in delivering women (M.V.) (n = 45: day, n = 24: night, n = 21) were significantly different. 2) Both TRP and KYN concentrations were significantly higher in U.A. and U.V. than those in M.V., the concentration gradient being approximately 1:2, and a positive maternal-fetal relationship was observed (r = 0.586-0.944, p less than 0.01). 3) A positive relationship was observed between the venous-arterial gradient of umbilical cord tryptophan and the Kaup Index (r = 0.316, p less than 0.05). 4) In order to minimize individual variations, the ratios of TRP and KYN levels in newborn venous plasma to those in the umbilical arteries were calculated (n = 11). These ratios started to increase at 20-50 hours after delivery, which suggested that the first milk feeding may alter the metabolism of tryptophan in neonates.

Adult↗
PubMed1990

[Quenching effect and analysis of cell proliferation in dual-laser flow cytometry with human endometrial adenocarcinoma cells in vitro].

We analyzed the characterization of DNA synthesized cells (S phase cells) in the proliferation. It is important that the fixation and cell cycle time of S phase cells and DNA qualitative changes, etc., be examined. We used the dual-laser FCM system of the Los Alamos National Laboratory in New Mexico and analyzed the cell cycle, especially changes in S phase cells both quantitatively and qualitatively. By the bromodeoxyuridine (BrdU)/Hoechst Quenching effect, we could detect differences in electric signals by adopting the differential fluorescence correction method. (1) The effects of sodium butyrate in gene expression were dose-dependent at human endometrial adenocarcinoma cells. (2) After double staining with Mithramycin and Hoechst33342, S phase cells incorporating BrdU under quenching gave from linear relative to arched bivariate contour histograms. (3) At 24 hours G1 phase synchronization of SB 1,3 and 5mM appeared in slow cycling cells after BrdU was added. These results suggest that the effect of sodium butyrate in human endometrial adenocarcinoma cells might be understood not only from the quantitative change, but also by the qualitative change in S phase cells.

Adenocarcinoma↗
PubMed1989

Isolation and characterization of a Chinese hamster ovary cell mutant with altered regulation of phosphatidylserine biosynthesis.

We have screened approximately 10,000 colonies of Chinese hamster ovary (CHO) cells immobilized on polyester cloth for mutants defective in [14C]ethanolamine incorporation into trichloroacetic acid-precipitable phospholipids. In mutant 29, discovered in this way, the activities of enzymes involved in the CDP-ethanolamine pathway were normal; however, the intracellular pool of phosphorylethanolamine was elevated, being more than 10-fold that in the parental CHO-K1 cells. These results suggested that the reduced incorporation of [14C]ethanolamine into phosphatidylethanolamine in mutant 29 was due to dilution of phosphoryl-[14C]ethanolamine with the increased amount of cellular phosphorylethanolamine. Interestingly, the rate of incorporation of serine into phosphatidylserine and the content of phosphatidylserine in mutant 29 cells were increased 3-fold and 1.5-fold, respectively, compared with the parent cells. The overproduction of phosphorylethanolamine in mutant 29 cells was ascribed to the elevated level of phosphatidylserine biosynthesis, because ethanolamine is produced as a reaction product on the conversion of phosphatidylethanolamine to phosphatidylserine, which is catalyzed by phospholipid-serine base-exchange enzymes. Using both intact cells and the particulate fraction of a cell extract, phosphatidylserine biosynthesis in CHO-K1 cells was shown to be inhibited by phosphatidylserine itself, whereas that in mutant 29 cells was greatly resistant to the inhibition, compared with the parental cells. As a conclusion, it may be assumed that mutant 29 cells have a lesion in the regulation of phosphatidylserine biosynthesis by serine-exchange enzyme activity, which results in the overproduction of phosphatidylserine and phosphorylethanolamine as well.

Animals↗
PubMed1989

Abortive infection with Sindbis virus of a Chinese hamster ovary cell mutant defective in phosphatidylserine and phosphatidylethanolamine biosynthesis.

The effects of phosphatidylserine starvation on the infection with Sindbis virus (an enveloped RNA virus) have been investigated in a Chinese hamster ovary (CHO) cell mutant (strain PSA-3) which requires exogenously added phosphatidylserine for cell growth because it lacks the ability to synthesize this phospholipid. When PSA-3 cells were grown in the absence of phosphatidylserine, the cellular contents of phosphatidylserine and also phosphatidylethanolamine produced through decarboxylation of phosphatidylserine decreased. Sindbis virus production in the mutant cells decreased immediately upon phosphatidylserine deprivation as did the contents of phosphatidylserine and phosphatidylethanolamine, whereas the cell growth, viability, and syntheses of protein, DNA and RNA remained normal for approx. 40 h phosphatidylserine starvation. Although PSA-3 cells grown without phosphatidylserine for 24 h were able to bind and internalize Sindbis virus almost normally, viral RNA synthesis was greatly reduced in the cells, suggesting that nucleocapsids of internalized Sindbis virus are not normally released into the cytoplasm. Unlike mammalian cell mutants defective in endosomal acidification, PSA-3 cells grown without phosphatidylserine were not resistant to diphtheria toxin. Furthermore, the yield of virions and viral RNA synthesis in PSA-3 cells were not completely restored on brief exposure of the cells to low pH medium following virus adsorption, which is known to induce artificial fusion of the viral envelope with the plasma membrane of normal host cells and then injection of viral nucleocapsids into the cytoplasm. Our data demonstrate the requirement of membrane phospholipids, such as phosphatidylserine and/or phosphatidylethanolamine, in CHO cells for Sindbis virus infection, and we discuss their possible roles.

Animals↗
PubMed1989

Degradation of arachidonyl phospholipids catalyzed by two phospholipases A2 and phospholipase C in a lipopolysaccharide-treated macrophage cell line RAW264.7.

The release of arachidonate was stimulated by lipopolysaccharides (LPS) from phosphatidylinositol (PI), phosphatidylcholine (PC), and phosphatidylethanolamine (PE) in a murine macrophage-like cell line, RAW264.7. We measured phospholipase activities in cell-free homogenates of macrophages with 2-arachidonyl PC, PE, and PI as substrates. The activities of two phospholipases A2, catalyzing cleavage of arachidonate preferentially either from PC or PE, were detected. These two phospholipase A2 activities showed different pH optima and Ca2+ requirements; the cleavage of arachidonate from PC showed an optimal pH of 7.0 and was Ca2+-dependent, while that from PE showed an optimal pH of 7.5 but was Ca2+-independent. The cleavage of arachidonate from PI showed a different pH profile and was Ca2+-dependent, and diglyceride (DG) was detected as well as arachidonate, suggesting that both phospholipase C and DG lipase participate in this reaction. We next examined these phospholipase activities in homogenates of macrophages pretreated with LPS. All of the phospholipase activities increased at 0.5 h after LPS treatment, and this level was retained for more than 2 h in 2-arachidonyl PC degradation, continued up to 1 h and then dropped to the control level in 2-arachidonyl PE degradation, and suddenly dropped to the control level after 0.5 h in 2-arachidonyl PI degradation. These results suggest that the cleavage of 2-arachidonate from PC, PE, and PI is essentially catalyzed through different pathways, two phospholipase A2 activities being involved in PC and PE breakdown, and phospholipase C and DG lipase activities in PI breakdown, and that the activities of these substrate-specific phospholipases change in response to LPS treatment in macrophages.

Animals↗
PubMed1989

Operative correction of a kinked duplicate origin of the vertebral artery in a patient with dizziness. Case report.

A 70-year-old woman was admitted to our hospital with complaints of severe dizziness and occipital headache. A right vertebral angiogram demonstrated a kinked, duplicated origin of the vertebral artery. Medical treatment was not effective, and an operative correction was attempted to improve the vertebral artery circulatory flow. The duplicate origin of the vertebral artery was confirmed at the time of surgery. Eight cases of duplicate origin of the vertebral artery in the literature are reviewed.

Aged↗
PubMed1989

Analgesia and anesthesia during labor in Japan and developed countries.

Analgesia and anesthesia during labor were surveyed by the use of a questionnaire sent to university hospitals in USA, UK, France, FRG, GDR, Japan, and also other types of institutions in Japan. A rather negative attitude toward analgesia and anesthesia during labor was encountered less often in Japan than in USA, UK, and FRG, but the actual frequency of use was much less in Japan. Narcotics and/or tranquilizers were most frequently used in the first stage of labor. The only exception was France where lumbar epidural anesthesia was actually used as a method of choice at 70% of the institutions. Lumbar epidural anesthesia or some other regional block was the method of choice in the second stage except in UK where inhalation of nitrous oxide was the method of choice at 48% of the institutions. Augmentation of labor was much more frequent and the number of annual deliveries were much less in Japan. Higher C-section rate was seen in USA.

Analgesia↗
PubMed1989

Synthesis of thyrotropin-releasing hormone-related peptides using N alpha-tert-butyloxycarbonyl-omega-(N-tert-butyloxycarbonylcarbamoyl)- alpha-amino acids.

Application of N alpha,Nca-di-tert-butyloxycarbonylhomoglutamine to synthesis of thyrotropin-releasing hormone (TRH) analogs was examined. The delta-lactam formation from homoglutaminylpeptides took place more easily than gamma-lactam formation from glutaminylpeptides in water or dioxane containing acetic acid. [pHgu1,Nva2]-TRH had dose-dependent antagonistic activity against pentobarbital anesthesia in mice, but almost no binding activity to TRH receptor in rat brain.

Amino Acids↗
PubMed1989

Multiple dural arteriovenous malformations. Report of two cases.

Two cases of multiple dural arteriovenous malformations (AVM's) in different locations are reported. One patient was diagnosed as having a dural AVM involving the right cavernous sinus that disappeared spontaneously 4 months after onset of symptoms. After an interval of 4 months, another dural AVM appeared involving the right lateral sinuses (transverse and sigmoid sinuses) with occlusion of the right sigmoid sinus. In the other patient, multiple dural AVM's were demonstrated on angiography, one involving the cavernous sinus and the other the left lateral sinus. The frequency of multiple occurrence and possible mechanisms of sinus occlusion are discussed.

Cavernous Sinus↗
PubMed1989

[Operative correction of kinking and coiling at the origin of vertebral artery and stellate ganglionectomy in patients with severe vertigo and dizziness].

Bilateral vertebral angiograms were taken in 125 cases with severe vertigo and dizziness during the period between April 1983 and March 1986. Various kinds of morphological abnormalities were found. Most impressive findings were kinking and coiling at the first portion of the vertebral artery, which was corrected by operation in 54 cases out of 100 cases. This method is accompanied with stellate ganglionectomy and completed by rolling the subclavian artery forwards and downwards with ligation. The follow-up results were evaluated one to four years after operation. Symptoms were cured in 50 cases out of 54. The postoperative course was satisfactory. It was emphasized in this paper that our operation was very useful for patients with severe and recurrent vertigo.

Adult↗
PubMed1988

Clinical effectiveness of a new cervical indwelling catheter in the management of premature rupture of the membranes: a Japanese collaborative study.

The aim of this multiinstitutional study was to evaluate a new cervical indwelling catheter in 84 patients with premature rupture of the membranes at less than 33 weeks' gestation. The average time of insertion of the catheter was 29.1 weeks' gestation, at an average of 2.0 days after rupture, and was left in place for an average of 6.5 days. The mean birth weight was 1417 gm. The mortality rate and the incidence of respiratory distress syndrome were 5.7% and 11.9%, respectively. Amniotic fluid culture was positive in 39.1% of patients before catheter insertion and only 4.3% at the time of delivery. Infection was noted in only four of 84 infants. The incidence of infection was very low in those treated for 3 days or more after catheter insertion.

Adult↗
PubMed1988

[Clinical study of the delivery of very low birth weight infants in Iwate Prefecture].

Over the past 4 years, 119 very low birth weight infants (VLBWI, less than 1,500g) were delivered at Iwate Medical University. We analysed clinical background of mothers and prognosis of neonates. The objective of this study was to upgrade our perinatal care tailored to regional demand. The following results were obtained. 1. Maternal transport was necessary in 90.7% of the mothers. Preterm Premature Rupture of the Membranes (PPROM) was present in 38.8% of them. 2. The percentage of mothers with a cervical dilatation of more than 4cm was significantly higher in mothers without PPROM than in those with PPROM. 3. Delivery occurred within 24 hours in 86.8% of mothers without PPROM who had a cervical dilatation of more than 4cm. 4. The percentage of cesarean sections was 16.5%. 5. Death in the neonatal period occurred in 10.8% of VLBWI, 20% of extremely low birth weight infants (ELBWI, less than 1,000g), and 42.8% of infants weighing less than 750g. 6. There was no significant difference in the incidence of intraventricular hemorrhage (IVH) between infants with cephalic presentation and infants with breech presentation, or between infants delivered vaginally and infants delivered by cesarean section. The incidence of IVH was significantly higher in infants weighing less than 1,000g than in those weighing 1,000g or more. 7. The neonatal death nate and the incidence of IVH were significantly higher in infants weighing less than 750g than in those weighing 1,000g or more. 8. The incidences of pneumonia and sepsis were significantly higher in infants with PPROM than those without PPROM.(ABSTRACT TRUNCATED AT 250 WORDS)

Cause of Death↗