Spatial distribution of the wave functions of a graphite surface studied by use of metastable-atom electron spectroscopy.
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Biomedical subjects
Publications and source records attributed to Y Harada.
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Exogenous [3H]leukotriene B4 (LTB4) was converted into several polar and non-polar metabolites in the chopped human lung. One of the major metabolites was identified as 5(S),12-dihydroxy-6,8,14-eicosatrienoic acid (10,11-dihydro-LTB4) by means of co-chromatography with authentic standards, ultraviolet spectrometry and gas chromatography-mass spectrometry. Analysis of chiral straight phase HPLC revealed the presence of both the 12(S) and 12(R) epimers of dihydro-LTB4. Dihydro-LTB4 was also formed from endogenously generated LTB4 in ionophore A23187 stimulated incubations. The dihydro metabolites were approximately 100 times less potent than LTB4 in causing guinea pig lung strip contraction and leukocyte-dependent inflammation in the hamster cheek pouch in vivo.
Three allotypes of murine factor H have been identified serologically in the previous study (denoted H.1, H.2, and H.3). A cDNA clone coding for the entire length of murine factor H was isolated from a library constructed from the livers of STR/N mice which have H.2 allotype and was fully sequenced. The insert of this clone (STR309) contained 4184 nucleotides and consisted of a 47-bp 5' noncoding region, a 54-bp coding for leader peptide, a 3648 bp for the mature factor H protein, and a 435-bp 3' noncoding region. Compared with the previously reported sequence of the cDNA clone (MH8) isolated from B10.WR mice that have H.1 allotype, the size of the protein coding region was exactly the same, but 21 nucleotide substitutions resulting in 15 amino acid replacements were observed. The amino acid replacement/nucleotide substitution ratio (0.71) is far higher than those observed in the allotypic variations of other proteins. Four 15-base oligonucleotide probes specific for either STR309 or MH8 were synthesized and used in Northern blot analysis. The probes specific for STR309 hybridized with mRNA isolated from the livers of STR/N mice but not with mRNA from the livers of BALB/c mice that have H.1 allotype, whereas the reverse pattern was observed with the oligonucleotide probes specific for MH8. These results strongly suggest that the nucleotide sequence of STR309 represents H.2 allotype of factor H protein, providing an example of an unusual allotype with high ratio of amino acid replacements to nucleotide substitutions.
The morphological and cytochemical changes of the Golgi apparatus and GERL of rat tracheal serous cells were studied after in vivo secretory stimulation with pilocarpine. Discharge of PAS-positive secretory granules had started within 30 min and complete discharge was finished within 2 h after stimulation. Reaccumulation of secretory granules became evident at 6 h and the volume of granules was similar to that of unstimulated control cells at 8 h. At 6 h after pilocarpine administration, acid phosphatase (AcPase) activity was markedly increased in GERL and immature secretory granules as compared to uninjected controls and this phenomenon continued 12 h after stimulation. GERL appeared to increase in extent and numerous continuities with immature granules were observed. Thiamine pyrophosphatase (TPPase) activity, normally present in trans Golgi saccules was not altered during the secretory cycle. At 2 h after stimulation, tubular structures of GERL, which also react to AcPase, were seldom observed. At 6 h, these structures were more numerous than those of control cells. These results demonstrate that, in rat tracheal serous cells, pilocarpine induces alteration of only GERL, and reconstitution followed by resynthesis of secretory granules is performed without participation of the Golgi stack.
The purpose of the present work is three-dimensional clarification of the overall configuration of the Golgi apparatus in rat tracheal serous cells including the sequence of structural modification during the secretory cycle induced by pilocarpine. From the results of both transmission electron microscopy from the serial sections, and scanning electron microscopy using the osmium-DMSO-osmium method based on maceration in dilute osmium tetroxide, the overall configuration of the Golgi apparatus shows that the Golgi stacks are joined together to make an interconnected, single Golgi complex in a cell. Connections, not only between the TGN (trans Golgi network) and rough ER (endoplasmic reticulum), but also between rough ER and cis cisternae are observed. This finding offers alternative routes for movement of substances through the cellular endomembrane system. During the secretory cycle induced by pilocarpine injection, it is evidenced that the disappearance of the TGN is accompanied by rapid discharge of secretory granules and the reconstitution of the TGN is followed by reformation of secretory materials. The beginning of the reconstitution of the TGN is indicated by vesicular buds from the sacculotubular element. These results indicate that the TGN participates directly in membrane recycling and in formation of secretory granules.
The functional significance of the vestibular dark cells in the guinea pig was investigated using ruthenium red staining technique. The apical cell surface of the dark cell was covered by the fuzzy layer of the glycocalyx, which could be responsible for water and ion transport across the apical plasma membrane. It has been suggested that the otoconia have been at first demineralized by an unknown mechanism when they are attached to the dark cell surface, and the mucopolysaccharide and mucoproteins in the otoconial matrix are then absorbed by active pinocytosis in the dark cells. These functions may be closely related to the possible regulation of the calcium ion in the vestibular endolymph.
Somatosensory evoked potentials were recorded from the frontal and parietal areas in patients with various lesions in the central nervous system on stimulation of the median nerve. Five representative cases who showed a selective loss of the positive potential from the frontal area are reported. In each case, the parietal N20 potential was relatively well preserved, and the midposition between the frontal and central areas (FC area) showed a negative potential following P14. The peak of this negative potential was synchronous with that of the parietal N20 potential. This negativity on the FC area is considered to be a volume conducted potential from the parietal N20 to the prerolandic frontal area. Such an anterior volume conduction of the parietal N20 would not be explained by the concept of a tangentially oriented dipole generated in the posterior bank of the central sulcus. Instead, for the generator of the parietal N20 potential, a radically oriented dipole generated mainly in the parietal area is postulated.
We investigated the ability of GM3-lactone liposomes to induce anti-melanoma T cell responses in mice. GM3-lactone liposomes, like murine B16 melanoma cells, induced anti-melanoma cytotoxic T cells (CTL) and also suppressor T cells (Ts). A small dose of GM3-lactone (0.0003 micrograms/ml) was enough to generate CTL in the in vitro primary response, whereas relatively large amounts of the antigen (0.03-0.3 microgram/ml) were required for anti-melanoma Ts induction. As the epitope for anti-melanoma Ts is NeuAc but not NeuGc residue on GM3, and anti-melanoma CTL are effectively induced by either GM3(NeuAc) or GM3(NeuGc)-lactone liposomes, GM3(NeuGc)-lactone or GM3(NeuGc) liposomes have potent activity as an artificial melanoma antigen to induce anti-melanoma CTL in vitro.
The purpose of this study was to determine whether left ventricular (LV) diastolic function in children with high blood pressure (BP) is abnormal. We measured the corrected LV isovolumic relaxation time (IRT), peak velocity of increase in LV dimension (dD/dt) and the LV muscle volume in a high systolic BP tracking group (10 boys and 22 girls) and a low BP tracking group (22 boys and 11 girls) at 3-year intervals from the ages of 6 to 15. The corrected IRT of the high BP tracking group was significantly longer than the low BP tracking group. Left ventricular dD/dt/D of the high BP tracking group was significantly lower than the low BP tracking group from the ages of 12 in boys and 9 in girls. The left ventricular muscle volume index of both groups, however, was not significantly different. Both corrected IRT and dD/dt/D were well correlated with diastolic BP. These data suggest that children in the high BP tracking group might have LV diastolic abnormalities from age 12 or 15, in contrast to children of the low BP tracking group, without increased LV muscle volume. Therefore, it might be useful to examine BP and LV function of children from ages 12 or 15 for prevention of hypertension.
Carbon fibers with fibrin glue were used as electrodes for diaphragm pacing. The electrodes were applied to three mongrel dogs and the effectiveness was tested. The carbon leads were glued to phrenic nerves by means of the fibrinogen and thrombin bilaterally. The tidal volumes and threshold current level for stimulation were measured at various time up to 9 weeks after implantation. Effective contraction of diaphragm were observed for 9 weeks. By using this electrode, the exfoliation of the nerve is not necessary, the nerve can be maintained in an intact state, and the risk of the implanting operation can be minimized.
The posterior semicircular canal of the frog was sinusoidally stimulated by mechanical endolympathic flow. Interaction of the excitatory and the inhibitory responses was analyzed on the spike density histogram. When the oscillation started in ampullofugal direction, the evoked action potentials were readily suppressed by the following ampullopetal stimulus. When the oscillation started in ampullopetal direction, the action potential appeared slowly, indicating that the inhibitory response has a longer time course than the excitatory response.
The ultrastructure of glycocalyx and ciliary interconnections of the human vestibular end organs was investigated in a three-dimensional way by using scanning electron microscopy. The plasma membrane showed a rather rough appearance, which was most prominent in the ciliary membrane of sensory cells. Ciliary interconnections emerged from the plasma membrane and tightly connected neighbouring cilia. The tip links stretched from the tips of the stereocilia to their taller neighbours. These tip links were arranged in the direction of the kinocilium. These findings indicate that the ciliary interconnections may keep the cilia arranged in a bundle and the tip links may be involved in the sensory cell transduction system.
The effect of the dosing schedule on aminoglycoside ototoxicity was investigated in the guinea pig. The animals were given amikacin or isepamicin either by once-daily intramuscular injection of 200 mg/kg or by twice-daily injections of 100 mg/kg for 28 days. The once-daily treatment induced a lesser degree of ototoxicity than the twice-daily injections, which may indicate that the once-daily treatment therapy has a potential value in the clinical use of aminoglycoside antibiotics. Isepamicin sulfate is a new aminoglycoside antibiotic currently undergoing clinical investigation. This study revealed that isepamicin also has ototoxic properties as has been observed in all other aminoglycosides. The degree of ototoxicity, however, was markedly less than that of amikacin.
We describe herein various sonographic features of uterine leiomyosarcoma. Transabdominal scanning (TAS) revealed an image indistinguishable from benign leiomyoma, with evidence of degeneration. Transvaginal scanning (TVS) clearly showed the thinness of the myometrium, and the possibility of deep myometrial invasion was suspected at intraoperative open direct ultrasonography (ODU). A very high peak systolic velocity and a slightly increased diastolic component at the periphery of the tumor were evident with pulsed Doppler ultrasound. Thus, TAS, TVS, ODU and Doppler ultrasound will yield useful information for the physician attempting to evaluate the extent and vascularity of uterine leiomyosarcoma.
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A 17-month-old boy was admitted to our hospital in a semicomatose state after a minor head injury. Computed tomography (CT) scans revealed a posterior interhemispheric and a thin convexity subdural hematoma. Two and a half hours later, repeated CT scans disclosed a development of the right hemispheric diffuse low density and an enlargement of the interhemispheric subdural hematoma. Decompressive craniectomy and removal of the hematoma was performed immediately. On the second postoperative day, the diffuse low density areas developed in the contralateral frontal and temporal lobes. On the 14th postoperative day, the gyri which had been low in density were markedly enhanced with contrast enhancement. On the 16th postoperative day, CT scans showed a diffuse hemispheric gyral high density with bleeding in the right parieto-occipital lobe. A right occipital lobectomy and removal of the hematoma was performed. Histological examination suggested cerebral infarction probably due to venous congestion. It is also suggested that the diffuse hemispheric gyral high density observed on the 16th postoperative day was the hemorrhagic cerebral infarction.
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We studied the pulmonary diseases which had developed as consequent deformities after healing of tuberculosis, which we called tuberculosis sequelae. Results are described as follows. 1. The frequency of tuberculosis sequelae was about 6% in the patients with pulmonary diseases admitted to our hospital. 2. 93 cases of them consisted of 4 groups, which were 39 of repeated bacterial infection of lower respiratory tract, 23 of pulmonary aspergilloma, 13 of atypical mycobacteriosis and 28 of chronic respiratory failure. 3. Patients with tuberculosis sequelae were distributed more in the younger age group than others with resembled pulmonary diseases. The men to women ratio was about 2:1. Patients with pulmonary aspergilloma were younger than those with atypical mycobacteriosis. 4. Death rate in tuberculosis sequelae was about 5% per year. 46% of patients with atypical mycobacteriosis and 44% with chronic respiratory failure died within 4 years. 5. In chest X-ray findings, fibrosis and shrinkage of the lung, compensatory pulmonary emphysema, deformity or dilatation of bronchi, bulla formation and residual tuberculous cavities were recognized in 40 to 65% of the cases. Severe pleural thickness or past thoracoplasty were frequently recognized in the patients with chronic respiratory failure. All the patients with pulmonary aspergilloma had one or more residual cavities. 6. The frequency of systemic complications was not more than in the control population matched by age. Comparatively, serum IgG and IgA were elevated and PHA-induced lymphocyte activation was not lowered in the patients with pulmonary aspergilloma and atypical mycobacteriosis. From these results, the main factor in the development of tuberculosis sequelae seemed to be local defects of the chest.