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K Kamiyama

Publications and source records attributed to K Kamiyama.

At least 73 records · Page 4Linked 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↗
PubMed1986

Interactions of alpha-chymotrypsin and Carlsberg subtilisin with methyl N alpha-acetyl-2-(alkylthio)-L-tryptophanoates.

Methyl N alpha-acetyl-2-(alkylthio)-L-tryptophanoates bearing different alkylthio groups were synthesized and employed as substrates for alpha-chymotrypsin and Carlsberg subtilisin in an attempt to investigate the properties of the hydrophobic pocket or cleft (S1 subsite) of the enzymes which accommodates the side-chain of the P1 amino acid residue of the substrates. The derivatives with ethylthio, 2-hydroxyethylthio, 2,3-dihydroxypropylthio, 2-aminoethylthio, carboxymethylthio, 2-carboxyethylthio, 1,2-dicarboxyethylthio, and 2-amino-2-carboxyethylthio (cysteinyl-S) groups were hydrolyzed by alpha-chymotrypsin but with kcat/Km values 4.6 to 15 times smaller than that of methyl N alpha-acetyl-L-tryptophanoate, due mainly to larger Km values. The glutathionyl derivative was only weakly bound to the enzyme. Analyses of the kinetic parameters suggested that the S1 pocket of alpha-chymotrypsin is rather more spacious than has been supposed and is able to interact flexibly with substrates so as to orient the scissile bond to the catalytic residues. On the other hand, none of the derivatives were hydrolyzed by Carlsberg subtilisin but they all inhibited the enzyme with Ki values which are generally smaller than the Km values for N alpha-acetyl-L-aromatic (modified aromatic) amino acid methyl esters. The S1 cleft of Carlsberg subtilisin interacts rather strongly with the derivatives but lacks the flexibility necessary for catalysis.

Amino Acids, Sulfur↗
PubMed1986

Characterization of human dental plaque formed on hydrogen-ion-sensitive field-effect transistor electrodes.

The purpose of this study was to evaluate (with scanning electron microscopy and microbiological characterization) the bacterial deposits which accumulate on hydrogen-ion-sensitive field-effect transistor electrodes (pH-ISFET) under conditions normally employed for telemetric monitoring of changes in human dental plaque pH. Electrodes were mounted in a carrier appliance which was worn for two, four, and six days. The plaque pH response to a sucrose solution increased with the age of the plaque, as expected from previous studies. After two days, the electrode was shown to be almost completely covered with cocci. At days 4 and 6 there was a dramatic increase in the number of rods present in the plaque. Adjacent enamel surfaces showed similar accumulations of bacteria. The total number of bacteria which had accumulated per unit area by day 4 was very similar for the electrode and enamel surfaces. On both surfaces the plaque contained approximately 25% streptococci, and the dominant species was Streptococcus sanguis (approximately 75%). The plaque which accumulated on pH-ISFET electrodes could not be distinguished visually or microbiologically from that which formed on control enamel surfaces.

Bacteria↗
PubMed1985

Inhibitory effect of interferon on the production of insulin.

Viral and bacterial infections may produce abnormalities in carbohydrate metabolism in normal subjects and profound changes in glucose homeostasis in insulin-dependent diabetics. Using an RIA with [125]porcine insulin, the effect of rat interferon (IFN) on the production/secretion of immunoreactive insulin (IRI) in cultured cells was investigated. We found that, after incubation of rat insulinoma cells with rat IFN, a decrease in the production of IRI was observed. The decrease correlated with the concentration of IFN and the length of the incubation. IFN also caused a decrease in the production/secretion of IRI from rat pancreatic beta-cells in primary culture. This IFN has all of the properties of IFN including species specificity, and the insulin inhibitory effect cannot be dissociated from the antiviral activity of IFN. These data suggest that one possible explanation for abnormalities in glucose metabolism associated with viral or bacterial infections is that virus-or bacteria-induced production of IFN may alter the concentration of insulin.

Animals↗
PubMed1985

[Neurofibromatosis associated with intra- and extracranial aneurysms and extracranial vertebral arteriovenous fistula].

Neurofibromatosis associated with vascular disorders is generally known as a vascular neurofibromatosis. In the neurosurgical aspect, it has been pointed out that "moyamoya disease" -like stenosis and/or occlusion of the internal carotid artery are seen in some of the patients with neurofibromatosis. This 58-year-old female with multiple café-au-lait spots and neurofibromas all over the body was admitted to our hospital with complaints of left orbital tumor and tinnitus. She had been suffering from the left intraorbital neurofibroma since ten years of age. Radiological examinations revealed left intraorbital neurofibroma extending into the intracranial cavity, multiple aneurysms and arteriovenous fistula. The aneurysms were located at the left vertebral-posterior interior cerebellar artery junction and at the extracranial internal carotid artery. The arterio-venous fistula was demonstrated at the left extracranial vertebral artery. Pathological changes of the blood vessels in the vascular neurofibromatosis are essentially obstructive lesions due to intimal thickening. Only few cases of neurofibromatosis associated with aneurysms and arteriovenous fistula have been reported, and eleven cases of them could be reviewed in the literature. Six are with intracranial aneurysms, two with extracranial aneurysms and three with extracranial vertebral arteriovenous fistula,. It is interesting that in all cases the extracranial vertebral arteriovenous fistula are located on the left side. This is corresponding to the fact that the bone defect around the asterion is predominantly seen on the left side in cases of neurofibromatosis.

Arteriovenous Malformations↗
PubMed1984

Electrothrombosis of spontaneous carotid-cavernous fistula by copper needle insertion.

Electrothrombosis by copper needle insertion was used to treat three cases of spontaneous carotid-cavernous fistula. These patients had been treated conservatively for 6 months or more, but their symptoms had not improved. Angiography showed that the feeding arteries were branches of both the ipsilateral internal and the ipsilateral external carotid artery. Frontotemporal craniotomy was performed, and copper needles were inserted transdurally into the cavernous sinus. Closure of the fistula was verified by intraoperative angiography in all cases, and the symptoms improved after the operation. However, one patient had postoperative transient 3rd nerve palsy. Another had Gerstmann's syndrome due to narrowing of the internal carotid artery by a needle and worsening of the preoperative 6th nerve palsy. In one case, the operation was uneventful. Based on our experience, we discuss several problems with this technique.

Arteriovenous Fistula↗