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Biomedical subjects

K Iijima

Publications and source records attributed to K Iijima.

At least 307 records · Page 17Linked to original sources
PubMed1982

An anthropometric study of cases with Turner syndrome and XYY.

Turner syndrome (45,X karyotype) is one of the few sex chromosome aberrations that can be recognized clinically during infancy or childhood. The features are short stature, broad shield chest, lymphedema of feet and legs, and webbed neck. On the other hand, boys with 47,XYY karyotype cannot be diagnosed from the clinical manifestations. Although the clinical features in Turner syndrome have been the subject of many reports, there have been few anthropometric studies on patients with Turner syndrome during childhood, and there have been no such studies on 47,XYY boys. This study was designed to determine the anthropometric characteristics of 11 patients with Turner syndrome diagnosed at the University Hospital, University of Tokyo, and 7 patients with 47,XYY found in a newborn survey in one maternity hospital in Tokyo.

Adolescent↗
PubMed1981

Developmental changes in the collagens and some collagenolytic activities in bovine dental pulps.

Collagen concentration was fairly low in young bovine 3rd premolar pulps, about 9 per cent by dry weight of pulp in stage I, but it increased consistently up to more than 25 per cent at stage V as the pulp matured. The ratio of type III to type I collagen similarly increased from 13 per cent at stage I to 32 per cent at stage V. Both collagenase and possibly collagenolytic neutral peptidases showed significantly high activity in the early stage of pulp development where the rate of collagen synthesis was also elevated. Higher rates of both collagen synthesis and its degradation might explain the low concentration and content in the early stage of pulp development.

Aging↗
PubMed1981

An HRP study on the distribution of all nuclei innervating the supraoptic nucleus in the rat brain.

Detailed histochemical studies have been performed on the distribution of the nuclei innervating the supraoptic nucleus (SO) in the whole brain after horseradish peroxidase (HRP) injections through fine glass micropipettes (2 to 8 micrograms ) into the SO of 39 Wistar strain rats. The chromatogenic reaction was carried out according to the Mesulam's (1976) No. 8 procedure. Successful HRP injections resulted in labeling in various regions of the brain. The following conclusions were drawn from the analysis of these successful cases. All the nuclei of the subthalamus and posthypothalamus innervate the SO whereas only a few neurons of the hypothalamic arcuate and ventromedial nuclei probably send axons to it. The afferent monoaminergic fibers arise largely from the B7 and B8, and to a certain extent from the A6 and A10 cell groups. The septum, diagonal band nucleus and amygdala project directly to the SO while the olfactory tubercle and pyriform cortex may not. The mesencephalic central gray has a high possibility to project directly to it. The possibility that the hippocampus sends axons to the SO remains to be fully proven. A few small multipolar cells clearly revealed by the test in the SO should be non-secretory intercalated neurons.

Animals↗
PubMed1981

The increase of glycosaminoglycan synthesis and accumulation on the cell surface of cultured skin fibroblasts in Werner's syndrome.

Glycosaminoglycans (GAGS) synthesis and accumulation on the cell surface of skin fibroblasts in two patients with Werner's syndrome were measured by the incorporation of 3H-glucosamine and 35S-sulfate. The strains of fibroblasts from Werner's syndrome (WF) had a much higher production of GAGS and accumulation on the cell surface than did the controls. Uronic acid was measured by means of the carbazole sulfuric acid method and orcinol method and it was revealed that WF fibroblasts had a large amount of total uronic acid in the cell layer, the largest portion being the iduronic acid fraction. Electrophoretic analysis of the GAGS of WF showed an increase of production. Increased release into the medium and accumulation of pericellular glycosaminoglycans was observed in hyaluronic acid (HA), heparan sulfate + dermatan sulfate (HS + DS), and chondroitin sulfate (CHS) fractions. No specific accumulation of GAGS in the intracellular pools was observed.

Adult↗
PubMed1981

The influence of calcium ions on the synthesis of collagen and glycosaminoglycans in human diploid cells in culture.

Synthesis of collagen and glycosaminoglycans of skin fibroblasts derived from an adult normal male in culture under different Ca2+ concentrations were investigated. Collagen synthesis was increased in hypocalcemic culture and decreased in hypercalcemic culture. Ca ionophore A23187 added to the medium caused reduction of collagen synthesis. From these results, it was suggested that intracellular Ca2+ controlled the collagen synthesis of fibroblasts. Uronic acid measurements of cell surface glycosaminoglycans (csGAGS) showed the reduction of uronic acid contents along with an increase of Ca2+ concentration in the medium. 3H-glucosamine and 35S-SO42-incorporation into csGAGS showed that glycosaminoglycans synthesis was reduced along with the increase of Ca2+ concentration in the medium. The results from the uronic acid measurement and the radio-isotope incorporation suggested that sulfated glycosaminoglycans, which contained isuronic acid in high proportions such as dermatan sulfate and heparan sulfate were increased in csGAGS in hypocalcemic culture.

Calcium↗
PubMed1981

Purification and characterization of bovine dental sac collagenase.

1. Active type collagenase was purified as much as 140-fold from the explant medium of bovine dental sacs and showed a single band on disc gel electrophoresis. Purified collagenase cleaved native collagen at only one locus under physiological conditions, but hydrolyzed neither gelatin nor alpha-casein. The optimal pH was about 7.8. 2. The molecular weight of active type enzyme was 35,000 by gel filtration and 34,000 by gel electrophoresis. The activation of latent type of collagenase resulted in the reduction of molecular weight from 45,000 to 38,000 by gel filtration. 3. A small but detectable amount of collagenase was directly extracted from frozen and thawed bovine dental sacs. In explant media of frozen and thawed tissue and fresh tissue with actinomycin D, some activity was detected for the first 2 days, but essentially no collagenase activity was detected in the explant medium after day 3. 4. The latent type collagenase was activated by trypsin, 4-aminophenylmercuric acetate (4-APMA), thiocyanate and deoxycholate (DOC). DOC showed irreversible dissociation of latent type enzyme in similar fashion to that exerted by 4-APMA. 5. The purified collagenase was inhibited by bovine serum, EDTA, o-phenanthroline, cysteine and dithiothreitol.

Animals↗
PubMed1981

Mortality and survival for Down syndrome in Japan.

Mortality and survival data for 1,052 Japanese patients with Down syndrome who were born between 1966 and 1975 were analyzed. The survival rate at age 10 was estimated to be about 86%. Mortality in each age group for Down syndrome was elevated over that of the general population. In the survival rate at age 10, there was no significant difference between males and females, but the difference between cases with and without congenital heart disease was highly significant. Using data from this study-for mortality up to age 10-and from the study of institutionalized cases for mortality over age 10, a hypothetical life table was constructed; it shows that the life expectancy at birth for cases with Down syndrome is nearly 50 years.

Adolescent↗
PubMed1981

[Cast structures and mechanical properties of Ir added to Ag-based alloys. (Part 1) (author's transl)].

The effect of very small quantity of Ir added to pure Agb or Ab-based casting alloys on the mechanical properties were investigated by microstructure observation, tensile test, XMA (electron probe micro analysis) and electrical resistivity measurement. 1) An addition of 0.005% Ir to pure Ag caused grain refinement, increased elongation, yield point, tensile strength. However, the refinement effect did not proportionally increase to the amount of additional Ir. 2) An addition of Ir to Ag alloy containing 7% Cu caused to finely dispersed beta phase in the as cast alloy and degraded the dendrite structure. As a result, homogenization and aging were accelerated. Mechanical properties i. e. elongation, yield point and tensile strength increased in castings and homogeneous state and yield point increased in aging state. The addition of about 0.05% Ir appeared optimum. 3) An addition of Ir to an Ag alloy containing 15% Cu caused grain refinement of the alloy as cast but its effect on the mechanical properties of the alloy was not clarified owing to casting defects. 4) 0.05% Ir added to an Ag alloy containing 20% Pd and 7% Cu did not show an apparent refinement effect. The optimum quantity of Ir is assumed to differ depending on the amount of Pd content.

Chemical Phenomena↗
PubMed1980

The birth prevalence of malformation syndromes in Tokyo infants: a survey of 14,430 newborn infants.

A survey of the birth prevalence of congenital anomalies among newborn infants in Japan is under way at a large maternity hospital in Tokyo. Of 14,430 consecutive newborn babies (7,455 M; 6,975 F), 33 had a multiple congenital anomalies (MCA) syndrome. These included 2 with trisomy 13 (including a mosaic), 3 with trisomy 18 (including 1 mosaic), 16 with trisomy 21 (including 1 mosaic), 1 with cri-du-chat syndrome, 1 with 5p partial trisomy, 1 with Hallermann-Streiff syndrome, 1 with Treacher-Collins syndrome, 1 with achodroplasia, 2 with arthrogryposis multiplex congenita, 1 with hemihypertrophy, 1 with Wiedemann-Beckwith syndrome, 1 with asplenia syndrome, 1 with Klippel-Trenaunay-Weber syndrome, and 1 with probable Marfan's syndrome. Except for one infant with Ullrich-Turner syndrome, cases with sex-chromosome aberrations could not be diagnosed neonatally on a clinical basis.

Abnormalities, Multiple↗
PubMed1980

An HRP study on cell types and their regional topography within the locus coeruleus innervating the supraoptic nucleus of the rat.

Detailed histochemical studies have been performed on the distribution of various types of horseradish peroxidase (HRP) labeled neurons in the rat dorsal pons with special reference to regional topography within the locus coeruleus (LC) after HRP injections into the nucleus supraopticus (SO). Successful HRP injections into the SO resulted in labeling only in the ipsilateral LC but not in the other structures of the pons. In these cases a few densely labeled multipolar neurons were scattered in both dorsal and ventral divisions throughout the LC. HRP deposition in the hippocampus proper increased significantly the number of labeled neurons in the dorsal division of the ipsilateral LC where a few fusiform neurons in addition to more numerous multipolar ones were labeled. These results strongly suggest that the LC must be the only site of the dorsal pons that innervates the SO, that mainly a part of multipolar neurons may project to the ipsilateral SO, and that regional topography within the LC innervating the SO must be very different from that innervating the hypothalamus. At the present time there remains a possibility that the LC may project to the contralateral SO.

Animals↗
PubMed1980

Purification and thermal stability of several amino acid-specific tRNAs from an extreme thermophile, Thermus thermophilus HB8.

Three species of methionine tRNAs and phenylalanine, tyrosine, and isoleucine tRNAs were purified from an extreme thermophile, Thermus thermophilus HB8. Formylation studies of the three methionine tRNAs and their codon-specific binding activities to ribosomes showed that two of them (named tRNAf1Met and tRNAf2Met) were initiator tRNAs and the other (named tRNAmMet) was a non-initiator. The tRNAs from T. thermophilus all had melting temperatures of up to ten degrees higher than the corresponding species from E. coli. Most of the species also had slightly higher G+C contents than the corresponding species of E. coli, and each of them contained one mol each of the modified nucleosides, O2'-methylguanosine (Gm), 2-thioribothymidine (s2T), and 1-methyladenosine (m1A). Their high melting temperatures could be explained by their high G+C contents and the presence of the modified nucleosides, espically s2T. Comparison of the melting temperatures of T. thermophilus tRNAf2Met with those of E. coli tRNAfMet and tRNAmMet at different magnesium concentrations showed that magnesium was also a factor in the thermostability of the thermophile tRNA.

Codon↗
PubMed1980

Demonstration of projections from locus coeruleus to supraoptic nucleus by the HRP method with special reference to cell types in the rat.

Histochemical studies have been conducted on the distribution of labeled neurons in the rat pons at the level of the locus coeruleus after HRP injections into the supraoptic nucleus. In all the fifteen cases in which the supraoptic nucleus was found to be included in the injection site, labeled neurons were detected in the locus coeruleus whereas in the other nine cases in which the injection site was outside the supraoptic nucleus, labeled neurons were not detected in the locus coeruleus. Six cases having the injection site successfully localized within the supraoptic nucleus showed definitely a few labeled multipolar neurons only in the ipsilateral locus coeruleus. These findings demonstrate the presence of an efferent projection arising from the locus coeruleus to the ipsilateral supraoptic nucleus. It is suggested that mainly multipolar neurons in both divisions of this nucleus may contribute to this projection. There remains a possibility that the locus coeruleus may project to the supraoptic nucleus on the contralateral side.

Animals↗