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A Kamei

Publications and source records attributed to A Kamei.

72 records · Page 4Linked to original sources
PubMed1987

Characterization of water-insoluble proteins in human lens nuclei.

Water-insoluble proteins from the nuclei of human normal and cataractous lenses were analyzed by solubilizing the lens material in various organic solvent/water mixtures. Gel permeation chromatography with TSK-3000 and TSK-4000 columns and a high performance liquid chromatography system were utilized to fractionate the water-insoluble proteins. The effective solvent systems were a) acetonitrile:tetrahydrofuran: water = 20:60:20, v/v%; b) tetrahydrofuran:water = 50:50, v/v%; and c) methanol:water = 25:75, v/v%. Different protein fractions could be selectively extracted with different solvent mixtures. The fractions obtained were partially identified using antibodies made against the soluble alpha-, beta-, and gamma-crystallins. Protein profiles obtained from cataractous nuclei differed markedly from those obtained from normal nuclei of the same age. In particular, an approximately 350K protein aggregate was found to increase with age in cataractous nuclei. This 350K aggregate is only a minor component in the nuclei of normal lenses.

Aged↗
PubMed1982

Effect of bongkrekic acid, a product of Pseudomonas cocovenenans, on thiol proteases.

The in vitro effect of bongkrekic acid on stem bromelain, papain and ficin was studied. The hydrolysis of casein by these enzymes was inhibited by bongkrekic acid, but the inhibition was always incomplete even with a large excess of the effector. Using a fully activated specimen of stem bromelain, purified on an organomercurial agarose affinity column, the inhibition by bongkrekic acid was not stoichiometric. The SH group of cysteine remained intact after incubation with an excess of bongkrekic acid at 24 degrees C for 20 min. However, partial inhibition of stem bromelain by bongkrekic acid was reversed by incubation at 37 degrees C for 5 min with 5mM cysteine or 2-mercaptoethanol. Ethylene glycol and glycerol had no such restorative effect. These results indicate that molecules of bongkrekic acid are non-covalently bound to a thiol protease, only partially and reversibly shielding its essential SH group.

Anti-Bacterial Agents↗
PubMed1979

Vitamin B2 activity of 7,8-dimethyl-10-(2,3,4-trihydroxy-4-formylbutyl)isoalloxazine in Lactobacillus casei.

The microbial activities of vitamin B2-aldehyde and vitamin B2-acid, produced by Schizophyllum commune, a Basidiomycete, were studied. Lactobacillus casei ATCC No. 7469 was used as a test microorganism. B2-aldehyde exhibited a good response curve in the growth of L. casei. B2-acid had neither a stimulatory nor an inhibitory effect on the growth. When B2-aldehyde was incubated with the homogenate of L. casei, it was converted to riboflavin. The flavin formed from B2-aldehyde by the homogenate not only exhibited an equivalent response curve to authentic riboflavin in the growth of L. casei, but also showed the same Rf value as authentic riboflavin in any paper chromatogram, as far as tested. Hence, the microbial activity of B2-aldehyde for L. casei seems to be ascribable to riboflavin which is a reduction product of B2-aldehyde.

Dose-Response Relationship, Drug↗
PubMed1978

Structure of extracellular polysaccharides of Escherichia coli strains 36M, 72M, and 29M isolated from coligranuloma of chick intestine. I. Polysaccharide from E. coli 36M.

An extracellular polysaccharide was isolated from culture broth of Escherichia coli 36M, and fractionated on a column of Sephadex G-150 into two fractions; the high molecular weight portion (85% of the total polysaccharide) contained pyruvic acid, and showed a positive immune reaction with anti-Ps-I-serum obtained from a rabbit. The low molecular weight portion (15% of the total polysaccharide) showed a negative immune reaction. The methylation, Smith's degradation, partial acid hydrolysis and methanolysis of the higher molecular weight polysaccharide revealed a repeating structure as follows: (see article).

Animals↗
PubMedDate not supplied

Olivocerebellar retrograde trans-synaptic degeneration from the lateral cerebellar hemisphere to the medial inferior olivary nucleus in an infant.

The neuropathological study of an infant with severe perinatal asphyxia showed specific neuronal loss in the medial part of the inferior olivary nucleus and the lateral part of the cerebellar hemisphere. This distribution suggests that the partial loss of olivary neurons is due to trans-synaptic degeneration from contralateral cerebellar hemispheric lesions, immunohistochemistrically demonstrated by axonal loss and swelling of neurofilaments.

Asphyxia↗
PubMedDate not supplied

A case of infantile spasms: epileptic apnea as partial seizures at onset.

We report a 2-month-old boy who presented with apneic attacks as a manifestation of epileptic seizures at onset and eventually progressed to infantile spasms. At onset, at 2 months of age, apneic attacks were the sole symptom of epileptic fits. Although these seizures were accompanied by cyanosis, bradycardia was not noted. An ictal electroencephalogram showed focal paroxysmal discharges in the temporal area. Treatment with sodium valproate was not effective to control his seizures. By 6 months of age, he progressed to infantile spasms. Although his seizures could be completely controlled with the use of zonisamide, vitamin B6 or high-dose immunoglobulin, his mental and behavioral development was retarded severely. There have been no previously published cases with infantile spasms that evolved from epileptic apnea as partial seizures.

Apnea↗
PubMedDate not supplied

Clinicopathologic studies on leptomeningeal glioneuronal heterotopia in congenital anomalies.

Leptomeningeal glioneuronal heterotopia was observed in 40 of 129 autopsied infants (31%). It was present in 49% of patients who had congenital anomalies in general and in 65% of patients who had central nervous system malformations. Most of the leptomeningeal glioneuronal heterotopias appeared in the base of the brain (62.5%), midbrain (40%), frontal lobe (37%), and pons (35%). Leptomeningeal glioneuronal heterotopia is closely related to migration disorders on the basis of frequent association with polymicrogyria or neuronal heterotopias.

Brain↗
PubMedDate not supplied

Abnormal dendritic development in maple syrup urine disease.

The neuropathology of a 6-year-old boy with maple syrup urine disease revealed spongy appearance of the white matter and marked edema of the brainstem. Golgi studies demonstrated aberrant orientation of neurons together with abnormalities of dendrites and dendritic spines. Similar changes were observed in a patient with dihydropteridine reductase deficiency. Disorders of amino acid metabolism may be associated with alterations in the terminal stages of neuronal migration and maturation.

Brain↗
PubMedDate not supplied

Developmental change in type VI collagen in human cerebral vessels.

Vascular development in the human brain was studied by immunohistochemistry using an anti-type VI collagen antibody. Positive vessels were evident from an early gestational age in the meninges, from 21 weeks gestation in the basal ganglia and deep white matter, and from 38 weeks gestation in the cerebral cortex and superficial white matter; however, type VI collagen never appeared in the subependymal germinal layer. The absent or scarce type VI collagen in the subependymal germinal layer may be one of the important factors of subependymal/intraventricular/periventricular hemorrhage in premature neonates. The earlier appearance of positive vessels in the deep white matter than in the cortex and superficial white matter suggests that the medullary vein develops earlier than the cortical and subcortical veins and arteries. These characteristics of the developing vascular structure may be one cause of perinatal brain damage.

Abortion, Spontaneous↗