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Biomedical subjects

S Shoji

Publications and source records attributed to S Shoji.

At least 271 records · Page 15Linked to original sources
PubMed1990

Bronchial epithelial cells produce chemotactic activity for bronchial epithelial cells. Possible role for fibronectin in airway repair.

Bronchial mucosal injury initiates a complex series of repair mechanisms, one of which is reepithelialization of a denuded lumenal surface. This suggests the hypothesis that bronchial epithelial cells, the cells initially affected by bronchial injury, might be able to initiate repair of an injured area by producing a chemotactic activity for intact bronchial epithelial cells. To evaluate this, bronchial epithelial cells were prepared from bovine lung by protease digestion and cultured in medium 199 (M199) with 10% fetal calf serum (FCS) until confluence, after which the cells were rinsed with Hanks' balanced salt solution, and serum-free fresh M199 was added. This conditioned medium was then collected and used to test the chemotactic response of bronchial epithelial cells using a blindwell chamber technique. Target cells for this assay were isolated from airways by protease digestion, grown to confluence in M199 with 10% FCS, and then harvested with trypsin. Bronchial epithelial cell-conditioned medium harvested after 3 days attracted more cells (197.0 +/- 5.7 cells/10 high power fields) than did M199 without FCS alone (4.3 +/- 0.9) (p less than 0.01). Checkerboard analysis showed that the migration was chemotactic. The chemotactic activity was nondialyzable, pepsin-labile, acid-stable, heat-labile, and lipid-inextractable. The chemotactic activity accumulated in the culture medium with time. The addition of 25 micrograms/ml of cycloheximide inhibited this accumulation. Column chromatography with Sephadex G-150 revealed a single peak of chemotactic activity in the high molecular weight range. The chemotactic activity was bound to gelatin-Sepharose 4B and was eluted with 6 M urea.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

Lung fibroblasts produce growth stimulatory activity for bronchial epithelial cells.

Interaction between lung fibroblasts and airway epithelial cells may play an important role in lung morphogenesis and airway repair after injury. Even though many reports have suggested that mesenchymal fibroblasts have a growth stimulatory effect on surrounding epithelial cells, very few have attempted to confirm and characterize the growth stimulatory activity in isolated cell systems. We cultured human fetal lung (HFL-1) fibroblasts, harvested supernatant-conditioned media under serum-free conditions, and examined their growth stimulatory effect on bovine bronchial epithelial cells by a variety of techniques, including direct enumeration, thymidine uptake, and metaphase arrest. We also partially characterized the growth stimulatory activity and examined the effect of an inhibitor of DNA synthesis on its release. The results demonstrate that HLF-1 fibroblasts release growth stimulatory activity for bovine bronchial epithelial cells. This activity is nondialyzable, protease-sensitive, acid-stable, and lipid-inextractable and thus appears to have the property of protein; it may be produced by de novo synthesis. Molecular sieve chromatography on Sephadex G-75 indicates an approximate molecular mass of 6,000 D. This growth stimulatory activity is likely to play roles in lung morphogenesis and airway repair after injury.

Animals↗
PubMed1990

Pulmonary macrophages can stimulate cell growth of bovine bronchial epithelial cells.

Macrophages are thought to participate in tissue repair following injury by releasing growth factors into the local environment. To evaluate whether pulmonary macrophages can mediate airway epithelial repair, we attempted to determine if pulmonary macrophages can stimulate growth of bovine bronchial epithelial cells in vitro. Bronchial epithelial cells isolated by protease digestion of the bovine bronchi were plated into tissue culture dishes with and without macrophage-conditioned medium. Bronchial epithelial cells cultured with macrophage-conditioned medium showed a significantly greater cell growth than those without macrophage-conditioned medium when assessed by direct enumeration of the cell numbers and by clonal growth assay. Stimulation of proliferation was confirmed by autoradiography using [3H]thymidine uptake into cell nuclei. Co-culture of pulmonary macrophages with bronchial epithelial cells also led to an increase in cell number. Immunohistochemical staining of the proliferating cells showed that these cells were positively stained by anti-keratin antibodies confirming that they were bronchial epithelial cells. Partial characterization of the activity in macrophage-conditioned medium showed that it was nondialyzable, pepsin- and acid-labile, and lipid-inextractable. Sephadex G-75 column fractionation indicated this activity existed in a high molecular fraction, thus suggesting a peptide. DEAE ion exchange chromatography revealed 3 peaks of stimulating activity. One peak resulted in a decrease in cell number, suggesting a possible inhibitory activity. The DEAE results thus suggest that macrophages may release several factors that can affect bronchial epithelial cell proliferation. In conclusion, pulmonary macrophages stimulate cell proliferation of bronchial epithelial cells in vitro. The stimulatory activity that may be heterogeneous appears to have the properties of a peptide.

Animals↗
PubMed1990

Bronchial epithelial cells respond to insulin and insulin-like growth factor-I as a chemoattractant.

Migration of epithelial cells to cover areas of injury is thought to be important in the repair process following airway insult. Insulin is reported to be a growth factor for bronchial epithelial cells, and growth factors have been known to be chemotactic for many types of cells. Thus, we hypothesized that insulin may be a chemoattractant for bronchial epithelial cells. To evaluate this, we prepared bronchial epithelial cells and measured their chemotactic activity toward insulin. Bronchial epithelial cells were isolated by overnight digestion with bacterial protease, filtered through 100-microns nitex mesh, and then cultured at 1 x 10(6) cells/ml in tissue culture dishes in medium 199 supplemented with transferrin, insulin, epidermal growth factor, hydrocortisone, antibiotics, and 10% FCS for 3 d. The cultured cells were rinsed twice to remove supplements, trypsinized and resuspended at 1 x 10(6) cells/ml in medium 199 without supplements, and used as the cell source for chemotaxis. Chemotactic activity of bronchial epithelial cells was measured by the blindwell chamber technique using 8-microns Nuclepore filter membranes coated with 0.1% gelatin. The cells were added to the top wells in a 48-multiwell chamber with insulin in the bottom wells and incubated for 6 h at 37 degrees C, 5% CO2. Bronchial epithelial cells migrated in response to insulin in a dose-dependent manner up to an optimal dose of insulin, 100 micrograms/ml, and decreased at higher concentrations. The number of migrated cells per 10 high power fields was 33.7 +/- 1.9 at the optimum and 3.7 +/- 0.7 without insulin (P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

Separation of bovine bronchial epithelial cell subpopulations by density centrifugation: a method to isolate ciliated and nonciliated cell fractions.

Bronchial epithelial cells isolated by protease digestion can be cultured in vitro for the study of proliferation and differentiation. However, these cells represent a heterogenous population, the components of which likely interact with one another. We attempted to utilize density gradient centrifugation as a method to prepare subpopulations of these bronchial epithelial cells. The suspension of the cells obtained by protease digestion of the bovine bronchi was mixed with an equal volume of colloidal silica reagent, Sepracell-MN, and centrifuged to form a continuous density gradient. Two distinct cell layers were identified in addition to a cell pellet at the bottom. Cells from fraction A (top layer) were more than 95% ciliated cells by morphologic examination. These ciliated cells were recovered intact as assessed by trypan blue dye exclusion and by watching beating of their cilia. The cells from fraction C (bottom layer) were 89.9 +/- 3.88% nonciliated, small round cells with a densely staining nucleus and scant cytoplasm. Comparison of cell morphology of these cells with basal cells in vivo and electron microscopic examinations suggested that these cells were basal cells. These basal cells showed an exponential cell proliferation until confluence in Ham's F12 with supplements, LHC9, and a 1:1 mixture of Medium-199 and modified Eagle's medium with 2% fetal calf serum. In contrast, the cells from fraction A grew minimally in all conditions tested. This difference was also shown in the study of DNA synthesis by [3H]thymidine uptake. Enzyme-linked immunosorbent assay for release of bovine fibronectin into cultured media indicated that fraction C cells secreted much more fibronectin (532 +/- 5.28 ng/10(6) cells/h) than fraction A cells (73.4 +/- 1.00). We also used Percoll as a density-gradient reagent and showed potential usefulness in the preparation of cell fractions of bronchial epithelial cells. In conclusion, it was possible to separate ciliated and nonciliated, presumably basal, cells of bovine bronchial epithelial cells. These differed in growth and fibronectin secretion. Studies of airway cell biology may be aided by the availability of more homogenous cell populations.

Animals↗
PubMed1990

Cardiac sarcoidosis.

The present report describes a patient with cardiac sarcoidosis who developed complete right bundle branch block, complete atrioventricular block and subsequent congestive heart failure. The patient demonstrated no clinical evidence of systemic sarcoidosis. Upon postmortem examination, the myocardium showed extensive noncaseating granuloma with numerous multinucleated giant cells. An initial routine microscopic examination of the lung revealed no evidence of granulomatous lesions. However, an extensive microscopic examination of the lung using serial sections demonstrated inconspicuous granulomatous lesions with giant cells. Thereby, a diagnosis of sarcoidosis was made. All other organs were free of granulomatous inflammation in spite of an extensive microscopic examination through serial sections. The present case suggests that a careful and extensive microscopic examination of the other organs may be necessary to establish a diagnosis of cardiac sarcoidosis.

Cardiomyopathies↗
PubMed1990

Induction of recurrent glomerulitis with accentuated glomerular lobulation by intermittent repetition of unilateral Masugi nephritis.

In order to induce a glomerulitis with lobular features, antirabbit renal glomerular basement membrane hen serum was intravenously injected into rabbits repeatedly at intervals of 3 weeks, during the course of clamping of contralateral renal arteries for 20 min. The first injection induced disorganization of the glomerular architecture accompanied by proliferation of local fixed cells and following crowding of the proliferated cells towards the axis of the loops and peripheral recanalization which brought about a lobular appearance of glomerulus. And the repeated injections induced repetition of such processes, resulting in accentuation or exaggeration of the lobular features of the glomeruli. The glomerular lesions presented here resembled closely to those of human lobular glomerulonephritis. Accordingly, the results of this study will offer some clue to understanding of the genesis of the human glomerular disease.

Animals↗
PubMed1990

Adenosine inhibits a GABAB receptor-mediated hyperpolarizing postsynaptic potential in neurons of rat septal nuclei.

Intracellular recordings were made from neurons of rat dorsolateral septal nucleus (DLSN), in vitro. Adenosine and 2-chloroadenosine (1-500 microM) hyperpolarized DLSN neurons and blocked the excitatory postsynaptic potential (EPSP) and the late hyperpolarizing potential (LHP) in the presence of bicuculline. Adenosine did not depress the glutamate-induced potential. Bath-application of adenosine depressed the baclofen-induced potential in 60% of the neurons. Adenosine also inhibited the LHP in the remaining 40% of neurons, while it did not depress the baclofen-induced potential in these neurons. These results indicate that adenosine inhibits the EPSP pre-synaptically whereas it inhibits the LHP both pre- and postsynaptically in rat septal nuclei.

Adenosine↗
PubMed1990

Features of regenerated clones with or without fusion treatment between auxotrophic mutants of Streptomyces antibioticus and their antibiotic productivity.

During experiments on protoplast fusion of complementary auxotrophic mutants (194 and 11M-21) of Streptomyces antibioticus for strain improvement, the clones (typified by F-40) regenerated on minimal regeneration medium (MRM) were found to be prototrophs, and to produce an antibiotic different from those produced by the parent strain. The protoplast regeneration of each parent was examined as a negative control experiment. In the regenerated clones of 194, half of them produced actinomycins similar to those produced by the original mutant 194, but others (typified by R-20) seemed to produce antibiotics similar to those produced by F-40. In the taxonomic characterization of morphological, cultural, and physiological properties of each strain, F-40, R-20, and the parent mutant 194 had no significant differences with a few exceptions. The problem here is whether the antibiotic of R-20 is the same as that of F-40, which was first isolated and found to be a peptide antibiotic different from actinomycins, with activity against Gram-negative and Gram-positive bacteria.

Anti-Bacterial Agents↗
PubMed1990

Widespread thrombosis and necrotizing arteritis of the liver in a 69-year-old woman with symptoms simulating those of temporal arteritis.

Autopsy findings of widespread thrombosis and necrotizing arteritis of the liver in a 69-year-old woman who had clinical symptoms suggesting those of temporal (giant cell) arteritis were presented. The lesion of the temporal artery was not of temporal arteritis but of thrombosis, part of widespread thrombosis, which occurred in the small arteries having hypertensive arteriolopathy. This case also had an arteritis of the liver resembling polyarteritis nodosa (PN). The pathologic processes demonstrated in this case suggested that the temporal arteritis-like symptoms may be brought about by occlusion of the temporal artery. Temporal arteritis is a nonfatal and self-limited disease and little information has been obtained from autopsy material. Accordingly, it is necessary to collect autopsy cases of temporal arteritis to investigate this disease through observations of whole bodies. Recently we examined a case which appeared clinically having symptoms of temporal arteritis, but the autopsy revealed that the symptoms were not brought about by temporal arteritis but by thrombosis of the temporal artery. It is the purpose of this paper to present this case and to discuss some problems concerning genesis of symptoms of temporal arteritis.

Aged↗
PubMed1989

Antimyristoylation of the gag proteins in the human immunodeficiency virus-infected cells with N-myristoyl glycinal diethylacetal resulted in inhibition of virus production.

The gag proteins of human retroviruses such as human immunodeficiency virus (HIV-1) are specifically myristoylated in their amino termini (1, 2, 3). N-myristoyl glycinal diethylacetal (N-Myr-GOA) and other N-Myr-compounds (N-Myr-Gly-GOA, N-Myr-Gly-Gly-GOA and N-Myr-Gly-Gly-Gly-GOA) were newly synthesized and investigated for activity of antimyristoylation of these gag proteins and for influence on viral replication. Of the N-Myr-compounds tested, N-Myr-GOA most severely inhibited the protein myristoylation; N-Myr-Gly-GOA also inhibited it, but moderately. Furthermore, it was observed that N-Myr-GOA at 20 microM caused noticeable inhibition (about 80%) of the production of mature HIV in the HIV-1-infected MT-4 cells. In this system, N-Myr-GOA substantially inhibited more than 90% of the N-myristoylation of p17 gag protein produced in the HIV-1-infected MT-4 cells. These results suggest that the N-myristoylation of p17 gag protein of HIV-1 may be essential in its structural assembly or maturation.

Acetaldehyde↗
PubMed1989

Antibodies to an NH2-terminal myristoyl glycine moiety can detect NH2-terminal myristoylated proteins in the retrovirus-infected cells.

Novel antibodies were raised against a synthetic NH2-terminal myristoyl glycine moiety which is characteristic of N-myristoyl-proteins. Antisera raised against N-myristoyl-Gly-hemocyanin reacted with N-myristoyl-Gly-[125I]albumin. The immunoreaction was competed for by albumin conjugated with N-myristoyl-glycine, while underivatized albumin had no effect. Of the [3H]myristate-labeled proteins detected, pp60v-src, which is a transforming protein of Rous sarcoma virus, and p19gag and p17gag, which are core proteins in the human T-cell leukemia virus and the human immunodeficiency virus, were identified as N-myristoylated proteins by the radioimmunoprecipitation analyses with the antibody.

Amino Acid Sequence↗
PubMed1989

Studies of protease inhibitors in the sera of patients with amyotrophic lateral sclerosis.

Serum levels of 4 protease inhibitors, alpha-1-antitrypsin, C1-inactivator, alpha-2-macroglobulin and antithrombin-III were measured in 11 patients with amyotrophic lateral sclerosis (6 males and 5 females) and a control group without neurologic disease. Our results indicated no significant differences in the level of serum alpha-2-macroglobulin between the 2 groups. We found slight but significantly lower levels of serum antithrombin-III in ALS. The possibility of the participation of proteases or protease inhibitors in the pathogenesis of ALS is discussed.

Amyotrophic Lateral Sclerosis↗
PubMed1989

Myofibrillar protein catabolism in rat steroid myopathy measured by 3-methylhistidine excretion in the urine.

The fractional rate of breakdown of myofibrillar protein in rat skeletal muscle was measured during subcutaneous cortisone acetate treatment (10 mg/100 g body weight per day). The daily urinary excretion of 3-methylhistidine divided by the 3-methylhistidine pool of the skeletal muscle was used to determine the fractional breakdown rate of myofibrillar protein. The mean fractional breakdown rate remained within the normal range throughout the first 5 days, but decreased significantly from the 16th day of treatment. When the daily 3-methylhistidine excretion was divided by the creatinine excretion, the rate showed the same trend of change. These results strongly suggest that the loss of myofibrillar protein induced by cortisone administration is not caused by increased breakdown but by decreased synthesis.

Animals↗