Collective motion of quantized vortex lines in rotating superfluid 3He-B.
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Journal Article↗
Biomedical subjects
Y Kondo
Publications and source records attributed to Y Kondo.
Recovery of viability in triploid hybrids between Japanese and European water frogs, and their reproductive capacity.
Diploid and triploid hybrids, consisting of the various combinations of chromosome set and cytoplasm between Rana nigromaculata and Rana lessonae, were generated in order to study their viability and reproductive capacity. Reciprocal diploid hybrids and allotriploids, which had two lessonae genomes and one nigromaculata genome in nigromaculata cytoplasm, all died without closing their neural folds. Allotriploids, which had two nigromaculata genomes and one lessonae genome in nigromaculata cytoplasm, all grew into healthy mature males in 12.4% (21 frogs) of zygotes. Following the elimination of lessonae chromosomes, ten of these males produced many spermatozoa containing a haploid set of nigromaculata chromosomes. Other allotriploids, which had either one nigromaculata genome and two lessonae genomes or two nigromaculata genomes and one lessonae genome in lessonae cytoplasm, exhibited slightly improved viability.
Animals↗
Bilateral projections of single retinal ganglion cells to the lateral geniculate nuclei and superior colliculi in the albino rat.
Employing fluorescent retrograde double/triple labeling, we investigated bilateral projections of single retinal ganglion cells to the lateral geniculate nuclei (LGN) and superior colliculi (SC) in the albino rat. After separate injections of Fast Blue (FB) and Diamidino Yellow (DY), respectively, into the right and left LGN, a large number of retrogradely-labeled cells were distributed all over the retina contralateral to each injection. Ipsilaterally projecting ganglion cells, which were labeled with one tracer injected into the LGN, were found predominantly in the lower-temporal retinal region; approximately 56% (120-140 cells per retina) of them were further labeled with the other tracer injected into the contralateral LGN. The vast majority of these double-labeled cells were of large type (more than 20 microns in diameter). Similar findings were obtained after separate injections of FB and DY, respectively, into the right and left SC, or respectively, into the right SC and left LGN. After separate injections of FB, DY and rhodamine-B-isothiocyanate, respectively, into the bilateral LGN and unilateral SC, or respectively, into the unilateral LGN and bilateral SC, a number of cells triple-labeled with all tracers were localized in the lower-temporal retinal region; most of them were of large type. Thus, the bilateral projections from the lower-temporal retinal region representing binocular vision in the rat are indicated to be achieved not only by separate populations of ganglion cells each exclusively serving one side of the brain, but also by axon collaterals from single ganglion cells; the ganglion cells projecting bilaterally to the LGN or/and SC are primarily of large type corresponding probably to the Y cell in the cat retina.
Amidines↗
The preventive effect of cyclosporin A, an immunosuppressant, on the late onset reduction of muscarinic acetylcholine receptors in gerbil hippocampus after transient forebrain ischemia.
We previously reported that a late onset reduction of muscarinic acetylcholine receptors (LORMAR) occurs in the gerbil hippocampus after 5 min of transient ischemia. This reduction begins as late as 7 days post-ischemia and accompanies the accumulation of glia, but is subsequent to completion of the disappearance of CA1 pyramidal cells. In the present study, we showed that this LORMAR was prevented by daily post-ischemic administration of the immunosuppressant cyclosporin A (CsA). The effectiveness of CsA against the LORMAR indicates that an immune mechanism may be involved in the progressive brain damage occurring after transient ischemia.
Animals↗
Observation of combined spin-mass vortices in rotating 3He-B.
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Journal Article↗
Enkephalin activates the phospholipase C/Ca2+ system through cross-talk between opioid receptors and P2-purinergic or bradykinin receptors in NG 108-15 cells. A permissive role for pertussis toxin-sensitive G-proteins.
In an NG 108-15 neuroblastoma x glioma hybrid cell suspension, extracellular ATP (via P2-purinergic receptors) and bradykinin stimulated Ins(1,4,5)P3 formation, which was accompanied by an increase in the cytosolic Ca2+ concentration ([Ca2+]i). Leucine enkephalin (EK) also slightly increased [Ca2+]i in the absence, but not in the presence, of apyrase, which hydrolyses extracellular ATP and ADP to AMP. When the cells were stimulated by P2-agonists or bradykinin prior to the application of EK, EK induces a remarkable rise in [Ca2+]i. This P2-agonist- or bradykinin-assisted EK action was also observed in single cells on a coverslip. A decrease in the extracellular Ca2+ concentration only slightly lowered the EK-induced rise in [Ca2+]i, but treatment of the cells with thapsigargin, an agent which depletes Ca2+ in the Ins(1,4,5)P3-sensitive pool, almost completely abolished EK action. The observed permissive stimulation by EK of Ins(1,4,5)P3 formation induced by a P2-agonist or bradykinin may be a primary event for the EK-induced [Ca2+]i rise. These actions of EK were antagonized by naloxone and completely reversed by prior treatment of the cells with pertussis toxin, whereas the toxin hardly affected the actions of P2-agonists and bradykinin themselves. Thus EK can induce phospholipase C activation and subsequent Ca2+ mobilization, provided that the cells have been previously or are simultaneously stimulated by endogenous adenine nucleotides or by externally applied P2-agonists or bradykinin. In this cross-talk mechanism between opioid receptors and these Ca(2+)-mobilizing agonist receptors, pertussis toxin-sensitive G-proteins play a permissive role.
Adenosine Triphosphate↗
Effects of core-level excitation on the F-center formation in KCl and KBr at liquid-helium temperature.
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Journal Article↗
Immortalization of normal human fibroblasts by treatment with 4-nitroquinoline 1-oxide.
Normal human fibroblasts (the OUMS-24 strain), derived from a 6-week-old human embryo, were transformed (into the OUMS-24F line) and immortalized by repeated treatments (59 times) with 4-nitroquinoline 1-oxide (4NQO). Treatment began during primary culture and ended at the 51st population doubling level (PDL). At the 57th PDL (146 days after the last treatment), morphologically altered, epithelial-type cells appeared, began to grow and became immortal (now past the 100th PDL). However, the control fibroblasts, which were not treated with 4NQO, senesced at the 62nd PDL. The finding that extensive, repeated treatments with 4NQO are required for the immortalization of normal human cells, indicates that multiple mutational events are involved in the immortalization of human cells in general. In other words, immortalization itself seems to be a multi-step process. Karyotypic analysis showed that many cells were hypodiploid before immortalization, but that afterwards chromosomes were distributed broadly in the diploid to tetraploid regions. The immortalized cells showed amplification and enhanced expression of c-myc. Two-dimensional electrophoretic analysis showed that the number of disappearing cellular proteins was greater than the number of the newly appearing ones after the cells became immortalized. Since the immortalized cells showed neither anchorage-independent growth nor tumorigenicity, they are useful for studying factors that can contribute to multi-step carcinogenesis in human cells. In addition, genetically matched normal (OUMS-24) and immortalized (OUMS-24F) cells will be useful for analyzing the genes related to cellular mortality and immortalization.
4-Nitroquinoline-1-oxide↗
Ischemia-induced changes in alpha-tubulin and beta-actin mRNA in the gerbil brain and effects of bifemelane hydrochloride.
Using in situ hybridization histochemistry, we examined changes in the cytoskeletal protein alpha-tubulin and beta-actin mRNAs in the gerbil brain 14 days after transient ischemia. In an attempt to identify the changes induced in the synthesis of cytoskeletal protein by ischemia, we also evaluated the effects of post-ischemia administration of bifemelane on these cytoskeletal proteins. alpha-Tubulin and beta-actin mRNAs were decreased in the CA1 region 14 days after transient ischemia. These decreases coincided with the loss of CA1 pyramidal cells, suggesting that they may have been related to delayed neuronal death. The beta-actin mRNA level in ischemic controls was significantly increased in the dentate gyrus, habenular nucleus, and medial and lateral thalamic nuclei, where some afferent nerves project into the hippocampal pyramidal cells. The increased beta-actin mRNA suggests that there may be a compensatory enhancement of actin synthesis in the afferent neurons that restores loosened synaptic connections with the ischemic cells in the CA1-4 fields. Administration of bifemelane just after recirculation prevented most of the ischemia-induced mRNA reductions in the CA1 field. Bifemelane's effect may be related to inhibition of Ca2+ influx and its radical scavenging activity. When bifemelane was administered to the ischemic group, alpha-tubulin mRNA levels significantly increased in the dentate gyrus and amygdaloid nucleus, and beta-actin mRNAs showed a tendency to increase in the CA3 and CA4 fields, dentate gyrus, and medial and lateral thalamic nuclei. These findings suggest that bifemelane may enhance synthesis of cytoskeletal protein, especially in the ischemic brain, inducing axon outgrowth or synapse formation.
Actins↗
High carrier rate after hepatitis B virus infection in the elderly.
An outbreak of hepatitis B virus infection occurred in a nursing facility; it involved 31 patients with sequelae of cerebral vascular accidents (15 men and 16 women; mean age, 77.4 +/- 9.3 yr). HBsAg disappeared within 6 mo in 9 patients and persisted during an observation period of more than 6 mo in 13; the remaining 9 patients were lost to follow-up while they carried HBsAg. Thus 13 of 22 patients followed (59%) became HBsAg carriers. We amplified a part of the S gene (436 nucleotides) with polymerase chain reaction on hepatitis B virus DNA from 12 randomly selected patients. The sequences of nine patients were the same as that of a nursing assistant who was an HBsAg carrier and suspected as the source of infection; it differed by only 1 or 2 (< 0.5%) nucleotides from those of the remaining three patients. Between the group of nine patients with transient HBV infection and the 13 patients with persistent HBV infection, we found no differences in age or sex or in parameters of nutrition or immunocompetence. These results indicate a high incidence of HBV carrier state in the elderly.
Adolescent↗
Hepatocellular carcinoma of the early stage: morphology and developmental process.
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Carcinoma, Hepatocellular↗
A comparison of current expressions of nasal patency.
Rhinomanometry is well established as a useful clinical method for objective assessment of nasal patency, although several expressions of nasal patency have been reported and universal standardization has not been achieved. In this communication, nasal resistances were calculated from the equation R = delta P/V (R; resistance; delta P; transnasal differential pressure; V; nasal airflow) at delta P 100 Pa and at peak flow. Time-averaged nasal resistances and integrated nasal patencies were measured in 350 adult patients by Rhinorheograph MPR-1100 and processed by a NI-101 computer program. The values from the equation R = delta P/V at delta P 100 Pa were slightly lower than those from the same equation at peak flow or those from the time-averaging method. Correlations between the values of nasal resistance at peak flow and the time averaging method were very close to the line of identity. No significant correlations were demonstrated between integrated nasal patency and the values from the other three expressions. The differences of the results from these expression are discussed.
Adolescent↗
Laminar organization of the substantia nigra pars reticulata in the macaque monkey, with special reference to the caudato-nigro-tectal link.
A laminar organization of the substantia nigra pars reticulata (SNr) was revealed in the macaque monkey by using an semihorizontal section plane parallel to the long axis of the SNr in the frontal plane. After injecting horseradish peroxidase conjugated to wheat germ agglutinin into the caudate nucleus (Cd) or putamen, anterogradely labelled fibres and axon terminals in the SNr were observed to form parallel bands in the anteromedial-posterolateral direction. After injecting Fast Blue into the superior colliculus, a cluster of retrogradely labelled neuronal cell bodies also formed a single band arranged in the similar anteromedial-posterolateral direction. The cluster was observed along the anterolateral margin of the SNr. This SNr region containing nigrotectal neurons appeared to overlap with one of the bands containing terminals of striatonigral fibres arising from the body of the Cd. The caudato-nigro-tectal link via the anterolateral marginal area might be involved in the control of saccadic eye movements.
Animals↗
DNA segments mapped by reciprocal use of microsatellite primers between mouse and rat.
Rat microsatellite primers were used for detection of homologous DNA segments in the mouse species (Mus laboratorius, Mus musculus musculus, and Mus spretus). Twenty five (16.3%) of 153 rat primer pairs amplified specific DNA segments, when genomic DNA of mice was used as a template in the polymerase chain reaction (PCR). Size variation among inbred strains of mice was found for 13 DNA segments (8.5%). Eight out of the 13 polymorphic DNA segments were mapped to a particular chromosome with two sets of recombinant inbred strains, AKXL or BXD. Similarly, mouse microsatellite primers were used for detection of homologous DNA segments in rats (Rattus norvegicus). Twenty (12.0%) of 166 primer pairs amplified specific DNA segments from rat genome. Size variation among inbred strains of rats was found for seven DNA segments (4.2%). Eleven of these 20 DNA segments were mapped with a rat x mouse somatic cell hybrid clone panel and/or linkage analysis by use of backcross progeny. Our results suggest that the mapped DNA segments are really homologs between mouse and rat. These polymorphic DNA segments are useful genetic markers.
Animals↗
Cranial MRI and MR angiography in Menkes' syndrome.
We report two boys with Menkes' syndrome who underwent cranial MRI and MR angiography (MRA). In both, CT and MRI revealed progressive cerebral atrophy with a subdural haematoma or effusion. Delayed myelination or dysmyelination of the white matter was suggested. Tortuosity of the cervical and intracranial vessels was well demonstrated by MRA, obviating more invasive conventional angiography should it be thought necessary to demonstrate the characteristic systemic vascular changes of this syndrome.
Atrophy↗
Regional changes in neuropeptide levels after 5,7-dihydroxytryptamine-induced serotonin depletion in the rat brain.
The levels of five neuropeptides (substance-P, somatostatin, cholecystokinin octapeptide, methionine-enkephalin and dynorphin) were examined in the brain and the spinal cord of rats 2 weeks after intracerebroventricular injection of 5,7-dihydroxytryptamine (5,7-DHT). 5,7-DHT injection caused a significant reduction of the serotonin level in all regions of the brain. The level of each neuropeptide except dynorphin significantly increased in specific regions of the brain after 5,7-DHT treatment without any decrease in their levels in any region. Since, coexistence and interaction between classical neurotransmitters and neuropeptides in the same neurons have been reported, both are indispensable for evaluating pathophysiological state of the brain function associated with abnormal neural transmission. The present findings together with previous reports suggest that neuropeptides act as neurotransmitters and compensate for the impaired function of the serotonergic systems.
5,7-Dihydroxytryptamine↗
Human T-cell leukemia virus type 1 protease protein expressed in Escherichia coli possesses aspartic proteinase activity.
We amplified the human T-cell leukemia virus type 1 (HTLV-1) protease gene fragment by polymerase chain reaction (PCR) and cloned it into a pUC plasmid vector. DNA sequencing data of the protease gene fragment indicated that it contained an open reading frame capable of encoding the active HTLV-1 protease. To express a fusion protein of beta-galactosidase linked with the HTLV-1 protease in Escherichia coli, a plasmid DNA was constructed by inserting the HTLV-1 protease gene DNA into a procaryotic expression vector, pUEX2, consisting of a lacZ gene directed by a lambda phage Pr promoter and designated pUEX-pro. By Western blot analysis using anti-beta-galactosidase antibody, a bigger molecular size band than that of the control beta-galactosidase molecule was observed in E. coli cells transformed with pUEX-pro but not with control pUEX2, suggesting that the particular fusion protein was successfully expressed. This recombinant protease protein in the E. coli cell lysate was demonstrated to be able to cleave the decapeptide substrates composed of amino acid sequences containing proteolytic cleavage sites in the HTLV-1 gag precursor polyprotein. The gag precursor polyprotein expressed in the mammalian cells by the recombinant vaccinia virus system was also expectedly cleaved by this enzyme. Significant inhibition of this protease activity by pepstatin A, an aspartic proteinase-specific inhibitor, confirms that HTLV-1 protease is a member of the aspartic proteinase group as suggested previously. Since the crude lysate without purification is utilized sufficiently as a native HTLV-1 protease reagent, this protease preparation is easily applicable to the large scale screening of HTLV-1 protease inhibitors for the treatment of diseases caused by HTLV-1.
Amino Acid Sequence↗
An autopsy case of ulcerative colitis associated with Takayasu's disease with a review of 13 Japanese cases.
An autopsy was performed on a 42-year-old Japanese female who had been suffering from both ulcerative colitis (UC) and Takayasu's disease. Her UC started at age 27 with bloody stool, and Takayasu's disease was diagnosed at age 30 on the basis of absence of pulse in her left arm. After more than ten years she died of multiple cerebral infarction. An autopsy study revealed the scarring stage of UC in the entire colon and aortitis in the aortic arch and its major branches and pulmonary arteries. Her HLA type was positive for HLA-A2, 24, Bw52 and 61. Clinical features of a total of 13 Japanese cases that had both UC and Takayasu's disease have been reviewed in the Japanese and Western literature.
Adult↗