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Biomedical subjects

Y Ohashi

Publications and source records attributed to Y Ohashi.

At least 577 records · Page 32Linked to original sources
PubMed1988

Aldose reductase inhibitor (CT-112) eyedrops for diabetic corneal epitheliopathy.

We treated two diabetic patients with corneal epithelial disorder that resisted conventional medical therapy with topical CT-112 (5-[3-ethoxy-4-pentyloxyphenyl]-2,4-thiazolidinedione), a newly synthesized aldose reductase inhibitor. One patient had developed recurrent corneal erosion after vitrectomy and the other had spontaneously developed superficial punctate keratopathy. The corneal lesion in each patient responded to topical CT-112 in two to four weeks and was almost cleared within two months. A similar corneal lesion recurred in both patients soon after CT-112 was discontinued, but it disappeared again when the drug was resumed.

Aged↗
PubMed1988

Subcellular distribution and isoelectric heterogeneity of the substrate for ADP-ribosyl transferase from Clostridium botulinum.

When the homogenate of bovine adrenal gland was subjected to subcellular fractionation, an Mr 21,000 substrate for botulinum ADP-ribosyl transferase was found not only in the membrane fractions but also in the cytosol; the amounts in the 10,000 x g precipitates and the 100,000 x g supernatant were about 21 and 56% of the total amount, respectively. Each fraction gave a single ADP-ribosylated protein band on SDS-polyacrylamide gel electrophoresis, but yielded on isoelectric focusing at least three bands between pH 5.5 and 6.0, suggesting the presence of multiple forms of the substrate of a similar molecular weight but different isoelectric points. ADP-ribosylated protein bands from the membrane and cytosol overlapped each other on both electrophoreses. After ammonium sulfate fractionation, the substrate from the cytosol showed requirement of divalent cations or guanine nucleotides for the reaction. Among cations tested, calcium, magnesium and manganese stimulated, whereas cadmium and lanthanum inhibited the reaction. Guanine nucleotides such as GTP, GDP and GTP-gamma-S also stimulated the substrate activity in the cytosol as that in the membrane fraction. However, no additive effects were observed when the nucleotides and cations were added together.

ADP Ribose Transferases↗
PubMed1988

An experimental study on the respiratory toxicity of isopropyl alcohol.

Guinea-pigs were exposed to 400 ppm or 5500 ppm of isopropyl alcohol (IPA) for 24 successive hours, and they were killed immediately after the exposure period. The ciliary activities of the nose and trachea were examined. In addition, the epithelium of the nose and trachea was observed by scanning and transmission electron microscopy. The present study showed that exposure to 400 or 5500 ppm of IPA vapor caused deterioration of the ciliary activity and also some pathological changes. Although our study revealed that exposure to 400 ppm of IPA vapor can affect the mucosa of the nose and trachea, the ciliary activity of the 400-ppm exposure group was not too poor and morphological changes were rather mild. Recovery from such degeneration might be rapid. Therefore, our study supports the justification of the allowable IPA level recommended by ACGIH.

1-Propanol↗
PubMed1988

Inhibition (in vitro) of replication and of the cytopathic effect of human immunodeficiency virus by an extract of the culture medium of Lentinus edodes mycelia.

An extract of culture medium of Lentinus edodes mycelia (LEM) was prepared. This was further fractionated by 50% ethanol precipitation and both the resulting product, E-P-LEM, and LEM were studied to evaluate their effect on the activity of human immunodeficiency virus (HIV) in vitro. The experiments were performed using either a cell-free infection system with MT-4 cells, or a cell-to-cell infection system with MOLT-4 cells, which induces multinucleated giant cells very efficiently. E-P-LEM almost completely blocked both the cytopathic effect of giant cell formation and specific antigen expression due to HIV, whereas LEM before ethanol precipitation blocked the expression of HIV antigen in MT-4 cells only at a high concentration. Pretreatment of the virus with E-P-LEM before infection blocked HIV infection in the target cells. Thus, the inhibitory effect of LEM and E-P-LEM on HIV could be due to a blocking of the initial stages of HIV infection. Moreover, reverse transcriptase activity of avian myeloblastosis virus was inhibited.

Acquired Immunodeficiency Syndrome↗
PubMed1988

Pharyngeal ciliary activity in guinea pigs with otitis media.

The function of cilia present in the tubotympanum plays an important role in the pathogenesis and chronicity of otitis media with effusion (OME). We used a photoelectric method to examine the ciliary activity in the eustachian tube, in the central pharynx, as well as the nasal cavity of normal animals and animals with otitis media. In normal animals, the ciliary activity in the nasal cavity was not different from that in the eustachian tube. In some animals with otitis media, however, there was a significant difference between the ciliary activity in the nasal cavity and that in the eustachian tube. On the other hand, no significant differences were recognized in any given group of animals examined between the level of the ciliary activity in the central pharynx and that in the eustachian tube. Our findings show that the function of the cilia present in the pharynx is a valid index of that in the eustachian tube. Our study further indicates that it may be possible to clinically assess the ciliary activity in the pharyngeal mucosa biopsied from patients with OME to determine objectively the effects of medical treatments of the disease.

Animals↗
PubMed1988

Characterization of adenovirus type 40 E1 region.

The left-most 3.9 kb of adenovirus type 40 (Ad40) DNA has been sequenced using cloned viral DNA fragments. The Ad40 E1 region is deduced to code for at least four polypeptides, 221 and 249 amino acids as E1A products in addition to 166 and 475 amino acids as E1B products. E1B polypeptides share about 50% homology with well-defined adenovirus types, 2/5, 7, and 12, throughout the E1B sequences. E1A homology of Ad40 to these types is relatively lower than that of E1B, while highly conserved regions of E1A are retained to a certain level in Ad40 as well. Activity for morphological transformation of Ad40 E1A on 3Y1 cells is considerably lower when compared to that of Ad5 and Ad12 E1A genes. Transient chloramphenicol acetyltransferase (CAT) expression assay shows that Ad40 E1A has a trans-acting function, though lower than that of other E1A genes, on adenovirus early promoter. The Ad40 E1A promoter also holds only a little cis-acting activity in 3Y1 cells. Lower activities of both Ad40 E1A promoter and certain E1A functions may explain in part the difficulty in propagation of Ad40.

Adenoviridae↗
PubMed1988

Toxicity of isopropyl alcohol exposure on the nasal mucociliary system in the guinea pig.

The toxicity of isopropyl alcohol (IPA) on the nasal mucosa in the guinea pig was experimentally studied, with special reference to the recovery process of the organ. The results showed that 400 ppm of IPA has an acute effect on the nasal mucosa and the recovery from such degeneration can occur in 2 weeks. When functional and morphological damages were induced by a higher level (5500 ppm) of IPA, it took over 2 weeks for complete recovery from such damage. The conclusion is that the present allowable level of IPA is reasonable from a viewpoint of the effect of short-term exposure to IPA on the nasal mucosa. In addition, a higher level of IPA exposure has a longer-term effect on the nasal mucociliary system in the guinea pig, and workers exposed to such a higher level of IPA should be given careful otolaryngological observation.

1-Propanol↗
PubMed1988

Functional and morphological pathology of the nasal mucosa after x-ray irradiation.

In our present study we examined the pathology of the nasal mucociliary system after x-ray irradiation in an animal model namely the rabbit. A reduced ciliary activity was observed immediately after the irradiation and did not show any recovery during our observation. No ciliary activity was seen in the nasal mucosa 8 weeks after the irradiation. Morphologically, hypersecretion of goblet cells was observed immediately after irradiation. Cytoplasmic vacuolation and nuclear pyknosis of ciliated cells started after irradiation, and sloughing of ciliated cells was observed for up to 3 weeks. Epithelial metaplasia started from 4 weeks, and no cilia were seen in the nasal mucosa and the surface of the epithelium was covered with flat squamous cells. Our present study shows that x-ray irradiation has serious influence on the function and structure of the nasal mucociliary system and that recovery from degeneration due to x-ray irradiation cannot be expected within several weeks.

Animals↗
PubMed1988

Reversibility of reduced ciliary activity on adenoids of patients with otitis media with effusion following culture.

We have studied the ciliary activity of the pharyngeal epithelium on adenoids obtained from patients with recurrent otitis media with effusion to assess indirectly the ciliary activity in the Eustachian tube. In conclusion, the following has been speculated from the present study: (1) middle ear effusions depress the ciliary activity; and (2) recovery of the reduced ciliary activity can be achieved in an effusion-free environment inasmuch as the ciliated cells have not undergone organic changes. Prompt elimination of the effusion, if present, is of critical importance for the recuperation of tubotympanic drainage, because a positive therapeutic effect resulting from elimination of the effusion can only be possible in early phase of the disease, before irreversible morphological lesions have occurred.

Adenoids↗
PubMed1988

Changes in bronchial response after Sendai virus infection in guinea pigs.

Enhanced bronchial reactivity to inhaled histamine was observed in guinea pigs infected with Sendai virus with concomitant decrease of beta-adrenergic receptor density in the pulmonary parenchyma 2 to 3 weeks after the inoculation. Histologic examination of the bronchi showed shedding of epithelial cells with a marked infiltration of mononuclear cells. These observations suggest that damage of the bronchial epithelium and decreased density of beta-adrenergic receptor may be the causes of observed bronchial reactivity.

Administration, Inhalation↗
PubMed1988

Stimulatory effect of vanadate on hyaluronic acid synthesis in mesothelial cells from rabbit pericardium.

Vanadate dose-dependently stimulated the incorporation of [3H]glucosamine into glycosaminoglycan, especially hyaluronic acid, in mesothelial cells from rabbit pericardium. The activity of hyaluronic acid synthase in the mesothelial cells treated with 50 microM vanadate for 0.5-1 h was stimulated to a level about 2 times over that of the control. Neither DNA synthesis nor protein synthesis in the mesothelial cells under the same experimental conditions was affected. The enhancement of the activity of hyaluronic acid synthase in the mesothelial cells treated with vanadate (50 microM) was not inhibited by the addition of cycloheximide (1 microgram/ml). These results suggest that vanadate stimulates the hyaluronic acid synthesis by activation of hyaluronic acid synthase in mesothelial cells from rabbit pericardium.

Animals↗
PubMed1988

Response of nasal ciliated cells of the guinea-pig during allergic reactions in human blood.

Nasal mucosal samples from thirty-five guinea-pigs were placed in a chamber, containing the medium RPMI 1640. Ciliary activity (beats.s-1) of the most active cell in each mucosal culture was measured using a photoelectric method. The RPMI 1640 was then replaced by 2 ml of RPMI 1640 and 1 ml of heparinized human blood from a non-allergic patient, with a ragweed-sensitive nasal allergy, or patients with D. farinae-sensitive nasal allergy: the ciliary activity of the same ciliated cell in each culture did not change significantly. We then added 1 micrograms of D. farinae extracts to evoke an in vitro allergic reaction. Ciliary excitation was induced when D. farinae extracts were added to the blood from D. farinae-sensitive subjects but not when added to blood from subjects without sensitivity to D. farinae. The peak and plateau of such an event occurred after 20-30 min. Ciliary stimulations were correlated with D. farinae-induced histamine release from whole blood. Thus, in vitro allergic reactions stimulate activity in cilia from normal nasal mucosa.

Allergens↗
PubMed1988

[The minimization method in a medium size clinical trial. Study of immunochemotherapy with PSK in gastric cancer].

One of the objectives of randomization is to balance the number of patients in each level and combination of levels of prognostic factors. However, as the number of possible prognostic factors increases, some imbalance may occur and make the results of the analysis less interpretable. In order to balance the marginal distribution of each factor and to facilitate more interpretable trial results, the "minimization method" reported by Pocock was applied in our multi-center immunochemotherapy clinical trial. Balancing in every institution was achieved by using Zelen's prespecified value d = 3 for replacing provisional assignment in the individual institution. Nonmetric principal component analysis in S, N factors which were used in minimization process showed good equilibration between groups. Also, in uncontrolled background factors, such as cancer pathology or Borrmann types, acceptable balance was obtained spontaneously at the end of the trial.

Clinical Trials as Topic↗