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Biomedical subjects

S Kato

Publications and source records attributed to S Kato.

At least 1,099 records · Page 61Linked to original sources
PubMed1992

[A case of pulmonary eosinophilic granuloma with involvement of the ocular fundus].

A 37-year-old man was admitted to our hospital because of abnormal shadows on chest X-ray film at routine medical examination. The chest X-ray showed diffuse granular shadows in the bilateral upper and middle lung fields. Chest CT showed multiple cystic lesions and nodular lesions. Bronchoalveolar lavage (BAL) and transbronchial lung biopsy (TBLB) were performed. Electron microscopic examination of BAL fluid revealed Langerhans' cells, and lung tissue specimen obtained by TBLB showed granuloma with infiltration of histiocytes and eosinophils. During the clinical course, the patient complained of cough and decrease of right visual acuity in association with an increase of abnormal shadows on chest X-ray. The lung disease gradually resolved after the cessation of smoking in spite of no therapy. In the right eye, an exudative lesion with retinal elevation was noted in the ocular fundus. Corticosteroid administration was effective for the treatment of this lesion. There was no pathological evidence of the right ocular lesion. However, the correlation of its clinical course with the lung disease suggests a relationship between the ocular lesion and pulmonary eosinophilic granuloma.

Adult↗
PubMed1992

Topographic dissociation between mitochondrial dysfunction and cell death during low-flow hypoxia in perfused rat liver.

BACKGROUND: Although it has been postulated that mitochondrial dysfunction and oxygen radicals may play a role in the mechanisms of hypoxic liver injury, little is known about the intralobular topographic relationship between a disorder in oxygen metabolism and cell death during hypoxia. EXPERIMENTAL DESIGN: Intralobular heterogeneity of mitochondrial dysfunction and its topographic relationship to cell death during 25% low-flow hypoxia was visually demonstrated in perfused rat hepatic microcirculatory units by dual-color digital microfluorography using rhodamine 123, a fluorochrome sensitive to the mitochondrial membrane potential, and propidium iodide, which labels the nuclei of nonviable cells with a concomitant enhancement of fluorescence. RESULTS: In the normoperfused liver from fasted rats, no significant depletion of the mitochondrial membrane potential values was observed in any portion of lobules during 100 minutes. In the liver treated with the 40-minute hypoxia, the mitochondrial membrane potential values within the entire lobule were significantly decreased. After a longer period of hypoxia, the pericentral fluorescence decreased to background levels, and the intralobular gradient showed a steep decline midway between the periportal and pericentral regions. Cell death was at first prominent in the midzone at 40 minutes, and then extended towards the pericentral regions, forming centrilobular necrosis at 100 minutes. Although allopurinol diminished the early midzonal cell death and retarded the development of centrilobular necrosis, it did not attenuate depression of the mitochondrial membrane potential. CONCLUSIONS: It is conceivable that mitochondrial dysfunction per se may not be related to the intralobular distribution of cell death during hypoxia. On the other hand, mitochondrial dysfunction in the centrilobular regions seems to be an important event leading to early midzonal oxidative tissue damage in that this change may involve ATP breakdown and the subsequent enhancement of xanthine oxidase-mediated oxidative cell injury in the midzonal regions, which are incompletely oxygenated.

Animals↗
PubMed1992

The domestication of Crocidura dsinezumi as a new laboratory animal.

The dsinezumi shrew (Crocidura dsinezumi), a small insectivore, has been bred for the first time as a laboratory animal. The original animals were captured using Sherman's live traps and transferred into wooden cages. After several generations they were housed in plastic cages. Their diet consisted of trout pellets, cat food, and water provided ad libitum. Monogamous pairs were housed together for 2-3 weeks for mating, and the male was separated from the female during delivery and nursing. In captivity, the reproductive activity was observed throughout the year and the gestation period was estimated at 28-30 days with a litter size of between 1 and 4 pups. Pups grew very rapidly, and reached adult body size (mean: male, 9.7 g; female, 8.3 g) and sexual maturation at 6-8 weeks of age. The reproductive life was estimated at one and a half years, while the longevity was approximately 2 years.

Animal Husbandry↗
PubMed1992

[Estimation of pulmonary vascular permeability by indocyanine green in permeability pulmonary edema].

In this study we attempted to estimate pulmonary vascular permeability by indocyanine green (ICG). Permeability pulmonary edema was produced in 9 adult dogs by injecting 0.08 ml/kg oleic acid. We injected 50 mg ICG intravenously in 18 dogs (9 dogs with pulmonary edema and 9 control dogs). We measured the time course of ICG concentrations in pulmonary arterial blood, ICG concentration of peripheral lung tissue, tissue/serum ICG concentration ratios, and wet/dry lung weight ratios. The following results were obtained. The time course of ICG concentration in pulmonary arterial blood showed peak values at 2 minutes and became constant at 5 or 10 minutes after injection. The ICG concentration in peripheral lung tissue, tissue/serum ICG concentration ratios, and wet/dry lung weight ratios in the pulmonary edema group were significantly higher than those in the normal group. There was a strong linear correlation between wet/dry lung weight ratio and ICG concentration in peripheral lung tissue, with correlation coefficients of r = 0.936 (p < 0.01) in the right lung and r = 0.901 (p < 0.01) in the left lung. From these results, we conclude that estimation of pulmonary vascular permeability by ICG is a useful method.

Animals↗
PubMed1992

[Aqueous protein concentration in diabetics. Report 5. Relationship between aqueous protein concentration and pathological findings of iridial vessels].

The relationship between aqueous protein concentration (APC) and pathological changes in the iridial blood vessels was investigated in 49 eyes of 45 diabetic patients who underwent cataract surgery. APC was measured with a laser flare-cell meter before surgery. The quantification analysis method (type I, multivariate analysis) revealed that the most relevant factor to APC was the existence of nephropathy followed by, in descending order, the degree of retinopathy and changes in iridial vessels as demonstrated by electron microscopy. When data were reanalyzed after exclusion of the iridial vessels were found to be strongly relevant to APC. These results suggest that breakdown of the blood-retinal barrier contributes to the APC increase in eyes with advanced diabetic retinopathy, and that changes in iridial vessels may mainly influence APC in non- and milder-retinopathy groups.

Aged↗
PubMed1992

[Clinical statistics of the Urological Clinic of Sapporo Sanjukai Hospital. Clinical statistics on patients admitted from 1985 to 1989].

A clinical statistic survey was carried out on the patient admitted, diseases and operations experienced at our urological clinic during 1985-1989. The total number of inpatients was 8,750 (The male to female ratio was 2.8:1). The major diseases of the inpatients were urolithiasis (4,134 cases, 47.2%) and benign prostatic hypertrophy (1,529 cases, 17.5%). Among the operations extracorporeal shock-wave lithotripsy 2,589 cases (44.6%) and transurethral resection of prostate 1,295 cases (22.3%) were predominant.

Adolescent↗
PubMed1992

Lateral elbow pain syndrome and entrapment of the radial nerve.

Lateral elbow pain syndrome is probably a fairly common condition and known to be resistant to conservative treatments. It is suggested that this syndrome is caused by entrapment of the radial nerve. Thirty patients with lateral elbow pain syndrome, in which entrapment of the radial nerve was diagnosed, have been operated upon to release the radial nerve at the elbow. There were 9 men and 21 women. Their age ranged from 17 to 64 with an average of 42.5. Twenty one of thirty nerves were entraped by the arcade of Frohse or other soft tissues. Nine nerves were adherent to the tissues overlying the radial head. Follow-up has been from six months to two years and eight months. Postoperative results were excellent in 16 patients, good in 11, fair in two and poor in one. These results would indicate that entrapment of the radial nerve at the elbow is considered as a cause of lateral elbow pain syndrome.

Adolescent↗
PubMed1992

[The mechanism of age-related change in lung elastic recoil pressure].

To investigate the mechanism of age-related change in lung elastic recoil, golden syrian hamsters were divided into three age groups (11-wk group, n = 20; 24-wk group, n = 25; 60-wk group, n = 15). Pressure-volume curves in isolated lungs, length-tension properties of alveolar wall, surface tensions by modified Wilhelmy balance, and collagen and elastin concentrations in the lung tissue were measured. Light and electron micrographs and morphometry were studied. Age-related change was not observed in lung elastic recoil in hamsters. However, old hamsters significantly increased a mean linear intercept and the elasticity constant of alveolar wall. On one hand, a surface tension was increased in old hamsters, associating with the decrease in the number of lamellar body of alveolar type 2 cells. These findings suggested that the reduction in lung elastic recoil which should be caused by both the increase in air space and the decrease in extensibility of alveolar wall would be compensated by the increase in surface tension in old hamsters, which may account for the no age-related change in elastic recoil in hamster lungs.

Aging↗
PubMed1991

Expression of Hanganutziu-Deicher antigen in activated human T lymphocytes.

Hanganutziu-Deicher (HD) antigen is a heterophile antigen that is widely distributed in many animals other than humans and chickens and is highly immunogenic in humans and chickens. In the present study, we demonstrated expression of HD-antigenic glycoproteins in activated T lymphocytes by SDS-PAGE and immunoblotting. Treatment with IL-2 plus PMA induced 29kD glycoprotein antigen detected under reducing condition. It contained sialic acid epitope of HD antigen because of the expression being neuraminidase-sensitive. Treatment with PMA plus A 23187 or PHA treatment and then PHA plus IL-2 treatment also induced two proteins of Mr 50kD and 70kD. These expressions were not detected in all individuals examined. These results indicate that HD antigen is an activated T cell antigen and expressed as an isoantigen as it is expressed in cancerous tissues from some patients.

Antigens, Heterophile↗
PubMed1991

Postnatal changes in sialylation of glycoproteins in rat liver.

Glycoproteins containing N-linked oligosaccharides were prepared from plasma and liver microsomes of rats aged 0-5 weeks, and galactose and sialic acid content were determined. The sialic acid/galactose ratios in plasma membrane N-glycans remained at about 1 throughout the postnatal period, suggesting that most of the galactose residues are sialylated. In the same way, it was suggested that most of the galactose residues of microsomal N-glycans were sialylated at 0, 4 and 5 weeks of age, but that the degree of sialylation was lower at the other ages, with a minimum at 2 weeks. When the activities of sialyltransferase and galactosyltransferase in liver Golgi membranes were determined, age-dependent changes were found, not only in the specific activities of the enzymes, but also in the Golgi membrane content per g of liver. The activity of galactosyltransferase per g of liver increased immediately after birth, whereas that of sialyltransferase remained at a low level for 2 weeks and then increased to a constant level at 4 weeks. It is probable that this delayed increase in the activity of sialyltransferase results in the decreased sialylation of microsomal N-glycans at 1, 2 and 3 weeks. Sialyltransferase was solubilized from the liver microsomes of rats aged 2, 3 and 4 weeks and characterized. Phosphocellulose column chromatography separated the activity into two subfractions, designated transferase I and transferase II in the order of elution. The increase in total sialyltransferase activity during this period was caused mainly by an increase in transferase I. Rechromatography of each transferase from 3-week-old rats after neuraminidase treatment showed that transferase I but not transferase II contained sialic acid residue(s) and that desialylated transferase I was eluted in a similar way as transferase II. Although the apparent Km value for CMP-N-acetylneuraminic acid and the heat stability of transferase I were different from those of transferase II, the difference was abolished by treating transferase I with neuraminidase, suggesting that transferase II may be a desialylated form of transferase I. These changes in the sialylation of membrane glycoproteins, including sialyltransferase, may be related to the control of liver growth during postnatal development.

Aging↗
PubMed1991

Electrostatic interaction of poly(L-lysine) with dipalmitoylphosphatidic acid studied by X-ray diffraction.

Structure of dipalmitoylphosphatidic acid (DPPA) bilayers in the presence of poly(L-lysine) is proposed from the results of X-ray diffraction obtained by a storage phosphor detector with a high resolution called an imaging plate. The small-angle X-ray diffraction pattern exhibits that DPPA/poly(L-lysine) complex forms a highly ordered multilamellar structure. The electron density profile of the DPPA/poly(L-lysine) complex draws that only one poly(L-lysine) layer is intercalated between the neighboring DPPA bilayers. The wide-angle X-ray diffraction pattern suggests that the presence of poly(L-lysine) hardly affects the nature of hydrocarbon chain packing in the DPPA bilayers. The X-ray reflection from the DPPA/poly(L-lysine) complex indicates that the poly(L-lysine) molecules adopt a beta-sheet conformation on the surface of the DPPA bilayers. The both surface areas occupied by a headgroup of the DPPA and by a lysine residue in poly(L-lysine) are estimated from the observed spacings. The number ratio of lysine residues to DPPA headgroups per unit area is greater than unity. Therefore, one DPPA headgroup interacts with more than one lysine residue electrostatically, i.e., the electric charge distributions in both the surface of a DPPA bilayer and the poly(L-lysine) beta-sheet are incommensurate.

Electrons↗
PubMed1991

Two distinct forms of peptidylprolyl-cis-trans-isomerase are expressed separately in periplasmic and cytoplasmic compartments of Escherichia coli cells.

Peptidylprolyl-cis-trans-isomerase (PPIase) is thought to be essential for protein folding in the cell. Two forms, a and b, of PPIase and their corresponding genes were isolated from Escherichia coli cells. Despite their insensitivity to cyclosporin A (CsA), both amino acid sequences were homologous and related to that of pig cyclophilin, a protein that has PPIase activity sensitive to CsA (Takahashi et al., 1989). PPIase a is found to be identical with the E. coli ORF 190 gene product that was sequenced by Kawamukai et al. (1989) and overexpressed by Liu and Walsh (1990). It is translocated into E. coli periplasmic space with the signal sequence. PPIase b lacks a hydrophobic amino acid stretch which could serve as a signal sequence or a transmembrane domain, and it is detected mainly in the bacterial cytoplasm. These findings indicate that proteins with the ability to assist folding of various polypeptides are located on both sides of the inner membrane. Thus, we propose that the folding of some exported proteins may be catalyzed by the periplasmic proline isomerase and, in turn, that some proteins which have isomerized may not be translocated efficiently.

Amino Acid Isomerases↗
PubMed1991

Quantitative determination of N-glycolylneuraminic acid expression in human cancerous tissues and avian lymphoma cell lines as a tumor-associated sialic acid by gas chromatography-mass spectrometry.

N-Glycolylneuraminic acid (NeuGc) is distributed in most animals except humans and chickens. However, human and chicken cancerous tissues often synthesize this heterophilic sialic acid as a tumor-associated Hanganutziu-Deicher antigen [M. Naiki and H. Higashi, Adv. Exp. Med. Biol., 152: 445-456, 1982; H. Higashi et al., Cancer Res., 45: 3796-3802, 1985]. In this paper, NeuGc in human cancerous tissues and chicken Marek's disease lymphoma cell lines was determined quantitatively with gas chromatography-mass spectrometry analysis using mass fragmentography. The detectable limit of NeuGc was 40 pg (0.12 pmol) in each injection using 5 ng of trideuteriomethyl ester trideuteriomethyl glycoside of the sialic acid as an internal standard sample when a pair of ions at m/e 386 and 389 was chosen for ion monitoring. NeuGc was detected in ganglioside-rich fractions of various human cancerous tissues from 5 of 8 patients examined but was not detected in glycosphingolipids of normal human tissues. The contents of NeuGc in these cancerous tissues ranged from 0.02 to 0.5% of the total sialic acid content. NeuGc was also detected in freeze-dried samples of 5 different cell lines from chicken Marek's disease lymphomas but was not detected in a cell line from chicken lymphoid leukosis lymphoma and normal chicken skeletal muscle tissue. The contents of NeuGc in the positive cell lines ranged from 0.03 to 0.11% of the total sialic acid content. These results indicate that NeuGc can be synthesized in both humans and chickens in some cancers.

Animals↗
PubMed1991

Genetic recombination in a chromosomal translocation t(2;8)(p11;q24) of a Burkitt's lymphoma cell line, KOBK101.

We analyzed a chromosomal translocation, t(2;8)(p11;q24), in a Burkitt's lymphoma cell line, KOBK101. The translocation reciprocally occurred between a site about 150 bp upstream from the J5 segment in the Ig kappa-encoding gene on chromosome 2 and the A-rich end of an Alu repetitive element located far downstream from the c-myc gene on chromosome 8. Short segments of both parental chromosomes were deleted at the rearrangement site. A sequence related to the heptamer recognition signal for the V-J recombination of Ig genes and a topoisomerase I-recognition sequence were detected at the breakpoints. The V-J recombination occurred on both chromosome 2 and the translocated chromosome 2p- at the J3 and J4 segments, respectively. The J region on the translocated chromosomes was mutated, as compared with that on the untranslocated chromosome, while the Alu element and its upstream sequence were conserved. These results suggest the following aspects to the chromosomal translocation of this cell line. A V-J recombination seems to have occurred at the proximal end of the J4 segment first, and then the translocation took place in the region between the J4 and J5 segments. The translocation may have been mediated by the functions of topoisomerase I and the Alu repetitive sequence located at the breakpoint, although the possibility cannot be ruled out that the recombination machinery for Ig gene rearrangements functioned irregularly.

Alleles↗
PubMed1991

Argyrophilic ubiquitinated cytoplasmic inclusions of Leu-7-positive glial cells in olivopontocerebellar atrophy (multiple system atrophy).

We described cytoplasmic inclusions in glial cells in 18 patients with olivopontocerebellar atrophy (OPCA) (multiple system atrophy, MSA). These glial inclusions showed intense argyrophilia with modified Bielschowsky's and Bodian's silver impregnation techniques, and were observed in the pons, cerebellar white matter, midbrain, medulla oblongata and basal ganglia, as well as cerebral white matter and spinal cord. None of the 54 control cases had glial argyrophilic inclusions. Immunohistochemically, these inclusions were intensely labeled by anti-ubiquitin antibody. Some of them reacted with an antibody to Rosenthal fiber (RF) protein. The cytoplasm of ubiquitinated inclusion-bearing glial cells was immunostained by anti-Leu-7 antibody, but not by anti-GFAP antibody. Ultrastructurally, the glial inclusions were composed primarily of approximately 24- to 40-nm fibrils, which were coated with osmiophilic granular material along their length in longitudinal section. These fibrils appeared as annuli in cross section. Often, a central granule approximately 5 nm in diameter was seen in the lucent lumen of a cross-sectioned fibril. The granule-coated fibrils were not seen in the glial filament-containing astrocytes. Electron microscopic examination of silver-impregnated specimens revealed that the granule-coated fibrils had strong affinity for silver. Immunoelectron microscopy using the indirect immunoperoxidase techniques with antibodies to ubiquitin and RF protein revealed that the electron-dense reaction products respective to both were located on constituents of glial inclusions. Our observation that Leu-7-positive glial cells, mainly oligodendroglial cells, had argyrophilic ubiquitinated inclusions may be of significance for the evaluation of the pathology of OPCA(MSA).

Adult↗