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M Nishijima

Publications and source records attributed to M Nishijima.

At least 217 records · Page 12Linked to original sources
PubMed1988

[A case of isolated cerebral angiitis with sequential angiographic changes].

The pathogenesis of migraine has not been completely understood. However, it is generally accepted that the prodromal symptoms encountered in classic migraine usually result from vasoconstriction of intracranial vessels, while the headache itself results from dilation of other cranial vessels, often branches of the external carotid artery. Despite of increasing refinement in angiographic technique, many authors demonstrate the difficulty of interpreting abnormal radiographic findings in patients of migraine. We experienced recently a rare case who complained of migraine with neurological disorder manifesting for dynamic changes of cerebral arteries on sequential angiography. This 39-year-old man was admitted to our hospital with complaint of classic migraine accompanied with transient hemiparesis of the left side. Curious dynamic changes were noted sequentially on the repeated angiograms sequentially during his hospitalization. The carotid angiogram on admission showed narrowing at the right M1 portion. The second angiogram obtained at the fourth hospital day showed reduction of the narrowing, and occlusion of the right angular artery. The patient was treated with Ergotamine. The third angiogram taken after admission for the period of 1 month showed increased stenosis at the right M1 portion. Isolated angiitis of central nervous system was suspected because of such sequential dynamic angiographic changes, and steroid therapy was started. However he began to suffer from hemiparesis of left side one week after the treatment. Therefore, EC-IC bypass was performed, and his symptoms were improved gradually. Migraine is one of the common neurologic disorders countered in clinical practice. This report suggests that careful observation is needed in patients of migraine.

Adult↗
PubMed1987

[A case of the duplicate origin of right vertebral artery].

A 70-year-old woman was admitted to our hospital with complaints of head heaviness and dizziness. Right vertebral angiogram demonstrated a duplicate origin of right vertebral artery with kinking at the both origins. Medical treatment was started immediately, but any improvement could not be obtained. So, surgical correction was attempted for the kinkings and the head heaviness and dizziness disappeared postoperatively. Duplicate origin of right vertebral artery could be confirmed at operation. Six cases of duplicate origin of vertebral artery were analyzed from the literature with special considerations to the genesis.

Aged↗
PubMed1986

A monosaccharide precursor of Escherichia coli lipid A has the ability to induce tumor-cytotoxic factor production by a murine macrophage-like cell line, J774.1.

A monosaccharide precursor of Escherichia coli lipid A, designated lipid X, which is a diacylglucosamine 1-phosphate with beta-hydroxymyristoyl groups at positions 2 and 3, was shown to have the ability to induce the production of tumor necrosis factor (TNF)-like tumor-cytotoxic factor by a murine macrophage-like cell line, J774.1. This cytotoxic factor was released from J774.1 cells grown in the presence of lipid X and related compounds, and it was assayed as to its lytic activity against [3H]thymidine-labeled L929 cells. Dose-response studies revealed that lipid X induced the production of smaller amounts of the tumor-cytotoxic factor than LPS at low concentrations, but it induced that of considerable amounts at and over 1 microgram/ml. Elimination of 1-phosphate or 3-O-beta-hydroxymyristoyl group from lipid X completely prevented the induction of producing this factor by the macrophages. Therefore, it is suggested that both 1-phosphate and 3-O-beta-hydroxymyristoyl groups are essential for the biologic activity of lipid X, as to the induction of the tumor-cytotoxic factor production in the macrophages.

Animals↗
PubMed1986

Phosphatidylserine biosynthesis in cultured Chinese hamster ovary cells. II. Isolation and characterization of phosphatidylserine auxotrophs.

Chinese hamster ovary (CHO) cell mutants that required exogenously added phosphatidylserine for cell growth were isolated by using the replica technique with polyester cloth, and three such mutants were characterized. Labeling experiments on intact cells with 32Pi and L-[U-14C]serine revealed that a phosphatidylserine auxotroph, designated as PSA-3, was strikingly defective in phosphatidylserine biosynthesis. When cells were grown for 2 days without phosphatidylserine, the phosphatidylserine content of PSA-3 was about one-third of that of the parent. In extracts of the mutant, the enzymatic activity of the base-exchange reaction of phospholipids with serine producing phosphatidylserine was reduced to 33% of that in the parent; in addition, the activities of base-exchange reactions of phospholipids with choline and ethanolamine in the mutant were also reduced to 1 and 45% of those in the parent, respectively. Furthermore, it was demonstrated that the serine-exchange activity in the parent was inhibited approximately 60% when choline was added to the reaction mixture whereas that in the mutant was not significantly affected. From the results presented here, we conclude the following. There are at least two kinds of serine-exchange enzymes in CHO cells; one (serine-exchange enzyme I) can catalyze the base-exchange reactions of phospholipids with serine, choline, and ethanolamine while the other (serine-exchange enzyme II) does not use the choline as a substrate. Serine-exchange enzyme I, in which mutant PSA-3 is defective, plays a major role in phosphatidylserine biosynthesis in CHO cells. Serine-exchange enzyme I is essential for the growth of CHO cells.

Animals↗
PubMed1986

Phosphatidylserine biosynthesis in cultured Chinese hamster ovary cells. III. Genetic evidence for utilization of phosphatidylcholine and phosphatidylethanolamine as precursors.

In the preceding paper, we reported that Chinese hamster ovary (CHO) cells contain two different serine-exchange enzymes (I and II) which catalyze the base-exchange reaction of phospholipid(s) with serine and that a phosphatidylserine-requiring mutant (strain PSA-3) of CHO cells is defective in serine-exchange enzyme I and lacks the ability to synthesize phosphatidylserine (Kuge, O., Nishijima, M., and Akamatsu, Y. (1986) J. Biol. Chem. 261, 5790-5794). In this study, we examined precursor phospholipids for phosphatidylserine biosynthesis in CHO cells. When mutant PSA-3 and parent (CHO-K1) cells were cultured with [32P]phosphatidylcholine, phosphatidylserine in the parent accumulated radioactivity while that in the mutant was not labeled significantly. On the contrary, when cultured with [32P]phosphatidylethanolamine, the mutant incorporated the label into phosphatidylserine more efficiently than the parent. Furthermore, we found that mutant PSA-3 grew normally in growth medium supplemented with 30 microM phosphatidylethanolamine as well as phosphatidylserine and that the biosynthesis of phosphatidylserine in the mutant was biosynthesis of phosphatidylserine in the mutant was normal when cells were cultured in the presence of exogenous phosphatidylethanolamine. The simplest interpretation of these findings is that phosphatidylserine in CHO cells is biosynthesized through the following sequential reactions: phosphatidylcholine----phosphatidylserine----phosphatidylethanolamine--- - phosphatidylserine. The three reactions are catalyzed by serine-exchange enzyme I, phosphatidylserine decarboxylase, and serine-exchange enzyme II, respectively.

Animals↗
PubMed1986

Phosphatidylserine biosynthesis in cultured Chinese hamster ovary cells. I. Inhibition of de novo phosphatidylserine biosynthesis by exogenous phosphatidylserine and its efficient incorporation.

The effect of phosphatidylserine exogenously added to the medium on de novo biosynthesis of phosphatidylserine was investigated in cultured Chinese hamster ovary cells. When cells were cultured for several generations in medium supplemented with phosphatidylserine and 32Pi, the incorporation of 32Pi into cellular phosphatidylserine was remarkably inhibited, the degree of inhibition being dependent upon the concentration of added phosphatidylserine. 32Pi uptake into cellular phosphatidylethanolamine was also partly reduced by the addition of exogenous phosphatidylserine, consistent with the idea that phosphatidylethanolamine is biosynthesized via decarboxylation of phosphatidylserine. However, incorporation of 32Pi into phosphatidylcholine, sphingomyelin, and phosphatidylinositol was not significantly affected. In contrast, the addition of either phosphatidylcholine, sphingomyelin, phosphatidylethanolamine, or phosphatidylinositol to the medium did not inhibit endogenous biosynthesis of the corresponding phospholipid. Radiochemical and chemical analyses of the cellular phospholipid composition revealed that phosphatidylserine in cells grown with 80 microM phosphatidylserine was almost entirely derived from the added phospholipid. Phosphatidylserine uptake was also directly determined by using [3H]serine-labeled phospholipid. Pulse and pulse-chase experiments with L-[U-14C] serine showed that when cells were cultured with 80 microM phosphatidylserine, the rate of synthesis of phosphatidylserine was reduced 3-5-fold whereas the turnover of newly synthesized phosphatidylserine was normal. Enzyme assaying of extracts prepared from cells grown with and without phosphatidylserine indicated that the inhibition of de novo phosphatidylserine biosynthesis by the added phosphatidylserine appeared not to be caused by a reduction in the level of the enzyme involved in the base-exchange reaction between phospholipids and serine. These results demonstrate that exogenous phosphatidylserine can be efficiently incorporated into Chinese hamster ovary cells and utilized for membrane biogenesis, endogenous phosphatidylserine biosynthesis thereby being suppressed.

Animals↗
PubMed1986

Somatomedin-C as a fetal growth promoting factor and amino acid composition of cord blood in Japanese neonates.

A study was undertaken to determine the relationship of somatomedin-C as a growth promoting factor to amino acid composition of umbilical venous blood in relationship to fetal growth. In full term pregnancy somatomedin-C from cases with appropriate fetal growth was greater than those with fetal growth retardation. Within the physical parameters of the neonate only birth weight of appropriate for date babies had significant positive relationship to somatomedin-C in cord blood. Of the 40 amino acids and their analogues, significant positive correlations were found for glutamine, prolin, asparagin, methionin, isoleucin and ethanolamine in relation to the level of somatomedin-C, while a significant negative correlation was found between tryptophane and somatomedin-C of appropriate for date babies. In cases with fetal growth retardation, the evaluation of amino acid-somatomedin-C relationship revealed that glutamine demonstrated a significant positive correlation and tryptophane demonstrated a significant negative correlation. While many details of these relationships are not clear, the results of this report lead us to speculate that somatomedin-C as a growth promoting factor in the fetus has some relationship to metabolites of tryptophane, for example serotonine and or melatonine, in regulating fetal growth in utero.

Amino Acids↗
PubMed1986

[Neurinoma of the oculomotor nerve: case report].

A case of solitary neurinoma of oculomotor nerve is reported. A 40-year-old female had a sudden headache with nausea and vomiting in January, 1978. She complained of diplopia and right ptosis two months later and visited a neurosurgical clinic, but radiological examination was told to be normal. Headache and right ptosis diminished, but diplopia continued. She was admitted to our clinic on Aug. 30, 1984, complaining of diplopia and right ptosis which were noticed only when she was tired. On admission, she had no neurological deficits except for right oculomotor nerve palsy. There was no cutaneous manifestation of von Recklinghausen's disease. Plain skull radiogram and angiogram showed normal study. CT scan showed a solitaly enhancing mass in the right prepontine region. On Sept. 22, 1984, a right frontotemporal craniotomy was performed, and the tumor was totally removed by pterional approach. The tumor was located beside the right internal carotid artery and the oculomotor nerve was incorporated in the tumor. The histological diagnosis was Antoni B type neurinoma. The clinical features of fourteen reported cases of neurinoma of the oculomotor nerve in the literature were reviewed.

Adult↗
PubMed1985

Enhancement of O2- generation and tumoricidal activity of murine macrophages by a monosaccharide precursor of Escherichia coli lipid A.

The effects of a monosaccharide precursor of Escherichia coli lipid A (lipid X) on murine macrophages were studied. Lipid X is a diacylglucosamine 1-phosphate bearing beta-hydroxymyristoyl groups at positions 2 and 3. Lipid X, as well as lipopolysaccharide and lipid A, enhanced O2- generation in mouse peritoneal macrophages and a macrophage-like cell line, J774.1, and further induced the tumor-cytotoxic activity of peritoneal macrophages. Elimination of a 1-phosphate or 3-O-beta-hydroxymyristoyl groups are essential for the elevated O2- generation and induction of tumoricidal activity due to lipid X.

Animals↗
PubMed1985

A temperature-sensitive Chinese hamster ovary cell mutant pleiotropically defective in protein export.

We have developed a new selection procedure for mammalian cell mutants defective in protein export by the use of diphtheria toxin, and devised a new screening method for defective protein secretion using nitrocellulose membranes. By the combination of these procedures, we have isolated a temperature-sensitive mutant clone of Chinese hamster ovary cells which shows a pleiotropic defect in protein export. This mutant, designated DS28-6, is temperature-sensitive for growth. Secretion of a series of proteins is markedly inhibited at the non-permissive temperature. These proteins seem to be normally synthesized and accumulated within the cell at the non-permissive temperature and secreted upon shift down to the permissive temperature. When this mutant is infected with vesicular stomatitis virus, oligosaccharide processing of G-protein is arrested at an endoglycosidase-H-sensitive stage at the non-permissive temperature. The lesion of this mutant appears to be in the endoplasmic reticulum or the cis Golgi or both.

Animals↗
PubMed1985

Alteration in the characters of CDP-choline synthetase and phospholipid-choline exchange enzyme upon choline starvation in Chinese hamster ovary cells.

When CHO-K1 cells are cultivated under choline-deficient conditions, the specific activity of CDP-choline synthetase increases and conversely phospholipid-choline exchange enzyme activity decreases, whereas the other three known enzyme activities related to synthesis of phosphatidylcholine remain unchanged. The changes of the former two enzyme activities take place immediately after removal of choline from the medium. The altered activities readily revert to the control levels upon resupplementation of choline to the starved cell culture. The changes upon choline starvation are sensitive to cycloheximide, while the restoration processes are insensitive to the drug. The activity of CDP-choline synthetase in unstarved control cells is found in both the soluble and membrane fractions. The Km value of the enzyme in the soluble fraction for choline phosphate differs from that in the membrane fraction. Asolectin alters the Km value of the former to a value close to that of the latter and raises its Vmax value, whereas it hardly affects the Km and Vmax values of the latter. In choline-starved cells, the activity is exclusively found in the membrane fraction. The change in the subcellular distribution of the activity upon choline starvation is sensitive to cycloheximide. The altered subcellular distribution reverts to the initial status upon resupplementation of choline even in the presence of cycloheximide. The activity of the phospholipid-choline exchange enzyme is exclusively found in the membrane fraction for both starved and control cells. The properties of the enzyme are altered upon choline starvation with respect to the Vmax value for choline and the Km and Vmax values for Ca2+. These altered kinetic parameters are changed by egg yolk phosphatidylcholine so as to be indistinguishable from those in unstarved control cells. We discuss the mechanism of the alterations in the characters of both enzymes in response to choline starvation.

Animals↗
PubMed1985

Spontaneous occlusion of traumatic carotid cavernous fistula after orbital venography.

A 50-year-old man was admitted to our hospital with a diagnosis of traumatic carotid cavernous fistula. The fistula was observed to disappear spontaneously just after orbital venography. This was confirmed by clinical examinations and subsequent carotid angiogram. The possible mechanisms responsible for the spontaneous occlusion of carotid cavernous fistula are discussed.

Adolescent↗
PubMed1985

Macrophage activation by monosaccharide precursors of Escherichia coli lipid A.

Certain Escherichia coli mutants defective in phosphatidylglycerol biosynthesis accumulate two novel glycolipids, designated X and Y. Lipid X is a diacylglucosamine 1-phosphate bearing beta-hydroxymyristoyl groups at positions 2 and 3, and lipid Y has the same structure as X, except for the additional presence of a palmitoyl moiety on the N-linked beta-hydroxymyristate. We have examined the activities of X, Y, and several related compounds as activators of macrophages. Both X and Y induce morphological changes (spreading), prostaglandin E2 synthesis, and killing of tumor cells by mouse peritoneal macrophages in vitro, properties with which lipopolysaccharide and lipid A are also endowed. Both glycolipids have similar effects on the macrophage-like mouse cell line J774.1. Selective removal from lipid X of either the ester-linked beta-hydroxymyristate at position 3 or the phosphate at position 1 abolishes activity. Our results show that the monosaccharides X and Y retain some of the properties of intact lipopolysaccharide and lipid A with respect to macrophage activation. Because the structures of X and Y are defined, our findings should facilitate the elucidation of the molecular mechanism of macrophage activation by lipid A.

Animals↗
PubMed1985

Isolation of a somatic-cell mutant defective in phosphatidylserine biosynthesis.

Mutant clones of Chinese hamster ovary (CHO) cells defective in the base-exchange reaction of phospholipids with choline were isolated by using an in situ enzymatic assay for the reaction in cell colonies immobilized on polyester cloth. The specific activities of the choline-exchange reaction in extracts of one of the mutants (designated 64) grown at 33 degrees C and 40 degrees C were 13% and 6% of those in parental (CHO-K1) cells, respectively. The choline-exchange activity in the mutant was more thermolabile in cell extracts than that in the parent, suggesting that a mutation in the structural gene for the choline-exchange enzyme might have been induced in this mutant. In culture medium supplemented with lipoprotein-deficient serum, mutant 64 grew almost normally at 33 degrees C but divided only twice at 40 degrees C and then stopped growing. Labeling of intact cells with [32P]Pi showed that mutant 64 was also strikingly defective in the biosynthesis of phosphatidylserine at 40 degrees C but was normal at 33 degrees C. Most temperature-resistant revertants of mutant 64 exhibited nearly normal ability to synthesize phosphatidylserine at 40 degrees C and also showed choline-exchange activity similar to that in parental cells. The addition of phosphatidylserine to medium supplemented with newborn calf serum, in which mutant 64 grew more slowly than parental cells at 40 degrees C, restored the growth rate of the mutant to the parental level. Our findings suggest that the choline-exchange enzyme functions as the major route for the formation of phosphatidylserine and that the temperature-sensitive growth of mutant 64 is due to a defect in phosphatidylserine biosynthesis at 40 degrees C.

Animals↗