Biomedical subjects
Publications and source records attributed to Y Ohashi.
We have examined the mucociliary function present in a mucocele of the maxillary antrum and have found certain abnormalities in the tissues studied. Our findings also indicate that the mucocele's intrinsic pathology is too complex to be improved by any conservative treatment and justifies its surgical removal.
Effects of Clomid, an ovulation-inducing drug containing clomiphene citrate, on Escherichia coli were investigated. Radiation-sensitive mutants, uvrA and recA, were more sensitive to Clomid than the parental wild-type strain. DNA synthesis in these two strains was more depressed by Clomid than that in the wild-type strain. Clomid caused DNA-strand breaks, but few SOS responses such as mutation, induction of prophage and expression of the umuC+ gene were induced.
6 cases in which a reamer or a cast object was swallowed into the stomach or into the bronchus during dental treatment are described, with a review of the Japanese literature. The foreign bodies were removed by duodenotomy in one case, by endoscopic or bronchoscopic procedure in three cases; spontaneous evacuation in the stool occurred in two cases. The management of patients who swallowed a foreign body into the airway or into the alimentary canal is discussed.
The influences of education and activity on memory of Japanese older adults were investigated. The Benton Visual Retention Test was given to 302 individuals (145 men and 157 women) aged 69 to 71 (average age 70) living in a suburb of Tokyo. Participants were retested 5 years later (average age 75). Memory as evaluated by Benton correct scores declined in both men and women during the 5 years. The influence of the first time Benton score, education, activity, and sex on the second-time Benton score was analyzed by multiple regression analysis. The second Benton score was strongly influenced by the initial score. Level of education and activity contributed to memory after 5 years. No difference in the magnitude of memory changes was found between men and women. The first time Benton score by education term showed a weak but negative contribution.
With the use of a reconstituted poly(ADP-ribosyl)ating enzyme system and three purified nucleases, micrococcal nuclease (MN), bull seminal RNase (BS RNase) and Ca2+, Mg2+-dependent endonuclease (BS DNase), as model acceptor proteins for ADP-ribose, the effect of ionic strength on the modification reaction was examined in detail. When these three nucleases were extensively poly(ADP-ribosyl)ated in this system at a low ionic strength (5 mM Tris), they were all inhibited by about 80% and the chain length of the polymer covalently bound to the nucleases was 13 to 23 ADP-ribose units. The observed inhibition was markedly prevented by increasing the ionic strength in the reaction mixture with a concomitant decrease in the polymer size bound to the nucleases. The NaCl concentrations required for decreasing the extent of the inhibition to half of the maximum were calculated to be 20, 50, and 100 mM for MN, BS RNase, and BS DNase, respectively. These values are similar to the NaCl concentrations required for decreasing the average chain lengths of the polymer to half, suggesting that the length of polymer is closely correlated to the extent of inhibition of these nucleases. DNA-binding affinities of these nucleases, expressed in terms of the NaCl concentrations required for eluting the enzymes from DNA-cellulose, were 140, 280, and 340 mM for MN, BS RNase, and BS DNase, respectively. Considering that maintainance of a ternary complex of poly(ADP-ribose) synthetase, acceptor and DNA may be essential for the modification reaction, the relatively strong salt effect observed in the modification of MN may be explained by its low DNA-binding affinity.
The synthesis of pathogenesis-related proteins (PR proteins), induced in tobacco leaves in response to infection with tobacco mosaic virus or treatment with salicylic acid, was studied with in vivo pulse-labeling experiments. PR proteins synthesis began after a lag phase of about 8 hours in leaf discs treated with salicylic acid and after more than 18 hours in those infected with tobacco mosaic virus. In both cases, the synthesis declined rapidly after 50 hours. The results show that the accumulation of PR proteins results from de novo synthesis and not from degradation of preexisting precursors and that the induced synthesis is transient like other stress-inducible proteins. The proteins have a half-life of at least 50 hours. The induction of these PR proteins was not inhibited by either 25 micrograms per milliliter of actinomycin D or 200 micrograms per milliliter of alpha-amanitin, which completely inhibited the increase of peroxidase activity in tobacco mosaic virus-infected leaf and the induction of heat shock proteins in tobacco leaf discs. These findings indicate that the induction of PR proteins is not regulated by a transcriptional step but by a translational step.
Immunologic conditions were studied in 8 patients with nasal allergies and nasal polyps and in 20 patients with nasal polyps. The present study showed the following: Nasal polyp mucosa contains a low level of mucosal IgE antibodies; nasal polyp mucosa is devoid of or deficient in the capacity of producing IgE antibodies; the presence of mucosal IgE antibodies in nasal polyp mucosa does not always imply the clinical manifestation of nasal allergies, and the antigen and antibody interaction does not always result in nasal symptoms.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Near-isocaloric diets with qualitative and quantitative differences in fat content have a profound influence on the manifestation and progression of the autoimmune syndrome that occurs in female MRL/lpr mice. In these animals, a high (9%) lipid intake resulted in a significantly higher mortality rate: 60% (saturated fat) and 75% (unsaturated fat) compared to 35% at 1 year for a group fed a diet low in fat. Furthermore, beginning at 7 months of age mice from both of the high fat diet groups exhibited a significantly higher incidence of proteinuria than mice in the low fat group. Immunologically, the group fed the high unsaturated fat diet had the highest incidence of anti-dsDNA autoantibodies, and the high saturated fat group had the poorest macrophage phagocytic function. The low fat diet preserved near 'normal' immune function in general, particularly IL-2 production. No significant differences were noted in either the production of rheumatoid factor or natural killer cell activity, irrespective of age or diet.
The role of virus-infected mononuclear leukocytes (MNLs) in the pathogenesis of neonatal herpetic chorioretinitis in newborn rabbits was investigated. As early as 2 days after inoculating the animals' skins with type 2 herpes simplex virus (HSV-2), infectious MNLs in the infected animals' peripheral blood were found. The virus was associated, for the most part, with MNLs that belonged to phagocytic and adherent cell fractions. Observations by electron microscopy indicated that HSV-2 was actively replicating in the MNLs. It was also found that as few as 80 virus-infected MNLs injected via the right common carotoid artery were capable of inducing the chorioretinal lesions in 50% of the eyes, but that as many as 10(3) Pfu of free virus were required to produce the same lesions in the same percentage of eyes. This result clearly indicated that virus-infected MNLs were far more efficient in producing chorioretinitis than free virus, and may thus play a crucial role in the pathogenesis of herpetic chorioretinitis in newborn rabbits. When 111In-labeled virus-infected or uninfected MNLs were injected into normal rabbits via the right common carotid artery, the virus-infected MNLs localized more readily in the eye than the uninfected MNLs. The virus-infected MNLs also attached to the cultured vascular endothelial cells significantly more often than the uninfected MNLs. These results suggested that virus-infected MNLs might be easily trapped in the circulation of the eye and, in this way, produce the ocular lesions.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Incubation of DNA polymerase alpha, DNA polymerase beta, terminal deoxynucleotidyl transferase, or DNA ligase II in a reconstituted poly(ADP-ribosyl)ating enzyme system markedly suppressed the activity of these enzymes. Components required for poly(ADP-ribose) synthesis including poly(ADP-ribose) polymerase, NAD+, DNA, and Mg2+ were all essential for the observed suppression. Purified poly(ADP-ribose) itself, however, was slightly inhibitory to all of these enzymes. Furthermore, the suppressed activities of DNA polymerase alpha, DNA polymerase beta, and terminal deoxynucleotidyl transferase were largely restored (3 to 4-fold stimulation was observed) by a mild alkaline treatment, a procedure known to hydrolyze alkaline-labile ester linkage between poly(ADP-ribose) and an acceptor protein. All of these results strongly suggest that the four nuclear enzymes were inhibited as a result of poly(ADP-ribosyl)ation of either the enzyme molecule itself or some regulatory proteins of these enzymes.
A new method to determine oligo- and poly(ADP-ribosyl)ated enzymes and proteins in vitro has been developed. This method is based on the facts that in Mg2+-depleted condition automodification of poly(ADP-ribose)polymerase is minimized and exogenously added acceptor protein is oligo(ADP-ribosyl)ated predominantly, and in Mg2+-fortified conditions the exogenous acceptor can be poly(ADP-ribosyl)ated. When 13 proteins, including several enzymes, were subjected to this system, dimeric bovine seminal RNase and micrococcal nuclease were found to be oligo(ADP-ribosyl)ated under Mg2+-depleted conditions but their activity was unchanged. Under Mg2+-fortified conditions however, the RNase was deactivated concomitantly with its extensive poly(ADP-ribosyl)ation. When dimeric bovine seminal RNase was monomerized in advance by treatment with dithiothreitol and urea, the enzyme lost ADP-ribose-accepting ability in spite of a significant residual enzyme activity. As used here successfully, the Mg2+-depleted and Mg2+-fortified ADP-ribosylation and subsequent chromatographic analysis of various proteins and enzymes might be an useful method for proving their oligo- and poly(ADP-ribosyl)ation.
Two male patients had corneal endotheliopathy of unknown origin. In both patients it was characterized by continuously progressing bullous keratopathy preceded by a line of keratic precipitates resembling a rejection line. The disease was progressive and did not respond to intensive corticosteroid therapy. No virus could be isolated from the aqueous humor, and the aqueous-antibody titers to herpes simplex, varicella zoster, and measles viruses were below detection level.