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Biomedical subjects

Y Okawa

Publications and source records attributed to Y Okawa.

At least 19 recordsLinked to original sources
PubMed1997

Structure of a cell wall mannan from the pathogenic yeast, Candida catenulata: assignment of 1H nuclear magnetic resonance chemical shifts of the inner alpha-1,6-linked mannose residues substituted by a side chain.

We performed an enzyme-linked immunosorbent assay of the cell wall mannan purified from the pathogenic yeast, Candida catenulata, using antisera to factors of the genus Candida. The results suggest that mannan possesses a linear backbone consisting of alpha-1, 6-linked mannose residues and side chains possessing nonreducing terminal alpha-1,2- and alpha-1,3-linked mannose residues. The chemical structure of the mannan was analyzed by two-dimensional homonuclear Hartmann-Hahn and two-dimensional nuclear Overhauser enhancement and exchange spectroscopy. The sequential assignments of the cross-peaks caused by J-coupling and the nuclear Overhauser effect from these terminal mannose residues demonstrate that the H1 signal of an inner alpha-1,6-linked mannose residue substituted by an alpha-oligomannosyl side chain or a single mannose through the C-2 position in an alpha-anomer configuration undergoes a significant downfield shift (delta delta = 0.16 or 0.19 ppm, respectively) compared with that of unsubstituted residues. We therefore propose the exact overall structure of the antigenic mannan obtained from C. catenulata. The assignment data in the present study are useful for the determination of the exact overall structure of various yeast mannans using the two-dimensional nuclear magnetic resonance analysis without the need for harsh procedures.

Antigens, Fungal↗
PubMed1996

Structure and antigenicity of the mannans of Candida famata and Candida saitoana: comparative study with the mannan of Candida guilliermondii.

The chemical structure of the mannans of antigenic factor 9-expressing yeast, Candida famata and Candida saitoana, was analyzed by acetolysis and NMR. The structural study of the oligosaccharides and mannans using one- and two-dimensional NMR indicated that the mannan of C. saitoana contains a third type of beta-1,2-linked mannose unit. On the other hand, the mannan of C. famata does not contain any beta-1,2-linked mannose units. The mannan of C. saitoana gave two groups of beta-1,2 linkage-containing oligosaccharides by acetolysis. One contains one beta-1,2-linked mannose unit and the other contains two consecutive beta-1,2-linked mannose units at the nonreducing terminal. The inhibition of the reactivity of factor 9 serum on an enzyme-linked immunosorbent assay (ELISA) with these oligosaccharides indicated that the inhibition activity of the former oligosaccharide is 1/20 of that of the latter ones. The ELISA of the mannans of Candida guilliermondii, C. saitoana, and Saccharomyces kluyveri, all of which contain the third type of beta-1,2-linked mannose unit, indicated that Man(beta)1--> 2Man(beta)1-->2Man(alpha)1-->3Man(alpha)1-->works as the antigenic factor 9 but Man(beta)1-->2Man(alpha)1-->3Man(alpha)1--> weakly behaves as both antigenic factors 6 and 9. The epitope structures of the side chain oligosaccharides agreed well with that proposed from the 2D-HOHAHA spectra of the mannans. This result demonstrates the usefulness of the H-1 - H-2-correlated cross-peak pattern, which was reported in a preceding paper (Shibata, N., Akagi, R., Hosoya, T., Kawahara, K., Suzuki, A., Ikuta, K., Kobayashi, H., Hisamichi, K., Okawa, Y., and Suzuki, S. (1996) J. Biol. Chem. 271, 9259-9266) for the determination of the epitope structure of Candida mannans without any chemical fragmentation.

Acetic Acid↗
PubMed1996

Identification of the antigenic determinants of factors 8, 9, and 34 of genus Candida.

We investigated the antigenic determinants of factors 8, 9, and 34 of the genus Candida among pathogenic yeasts by enzyme-linked immunosorbent assay (ELISA) using mannans of Saccharomyces cerevisiae wild type and mutant types, mnn 1-mnn 4 and mnn 2. Results of ELISA including antisera against the antigenic factors of genus Candida (Candida Check, latron; FAbs) indicated that these three types of mannan distinctly react with FAbs 34, 8 and 9, respectively. To identify the recognition sites of these FAbs, we compared the ability of various oligosaccharides to inhibit the binding of the mannans to FAbs. The results indicated that FAb 34 preferentially recognizes linear side chains containing a non-reducing terminal alpha-1,3-linked mannose residue, Man(alpha)1 --> 3Man(alpha)1 --> (2Man(alpha)1 --> )n(2Man) (n > or = 0), and that one of the recognition sites of FAb 9 is linear alpha-1,6-linked oligomannosyl series, Man(alpha)1 --> (6Man(alpha)1 --> )n(6Man) (n > or = 2). On the other hand, the recognition site of FAb 8 apparently consisted of two alpha-1,2-linked oligomannosyl side chains and an alpha-1,6-linked mannose residue that originated from the mannan backbone, Man(alpha)1 --> 2Man(alpha)1 --> 2(Man(alpha)1 -->2Man(alpha)1 --> 6)Man.

Antigens, Fungal↗
PubMed1996

Characterization of alpha-1,6-mannosyltransferase responsible for the synthesis of branched side chains in Candida albicans mannan.

A particulate insoluble fraction from Candida albicans NIH B-792 (serotype B) strain cells was obtained as the residue after extracting a 105000 x g pellet of cell homogenate with 1% Triton X-100. Incubation of this fraction with a mannopentaose, Man alpha 1-->3Man alpha 1-->2Man alpha 1-->Man alpha 1-->2Man, in the presence of GDP-mannose and Mn2+ at pH 6.0 gave a branched mannohexaose, [sequence: see text] 6 the structure of which was identified by means of sequential off assignment. However, the enzyme fraction obtained from Candida parapsilosis gave Man alpha 1-->2Man alpha 1-->3Man alpha 1-->2Man alpha 1-->2 Man alpha 1-->2Man under the same conditions. These results demonstrate the finding that the structural difference in the mannans of these two species is due to the presence of alpha-1.6-linked branching mannose units in the C. albicans mannan [Shibata, N., Ikuta, K., Imai, T., Satoh, Y., Satoh, R., Suzuki, A., Kojima, C., Kobayashi, H., Hisamichi, K. & Suzuki, S. (1995) J. Biol. Chem. 270, 1113-1122]. The substrate-specificity study of the enzyme indicated that the structural requirement of the alpha-1,6-mannosyltransferase is Man alpha 1-->3Man alpha 1-->. The alpha-1,6-mannosyltransferase also transferred the alpha-1,6-linked branching mannose unit to the mannan of Saccharomyces cerevisiae. The transformation of the mannan was detected by the appearance of antigenic factor 4 using an enzyme-linked immunosorbent assay and two-dimensional homonuclear Hartmann-Hahn spectroscopy.

Candida↗
PubMed1996

Existence of novel branched side chains containing beta-1,2 and alpha-1,6 linkages corresponding to antigenic factor 9 in the mannan of Candida guilliermondii.

Isolation of beta-linkage-containing side chain oligosaccharides from the mannan of Candida guilliermondii IFO 10279 strain has been conducted by acetolysis under mild conditions. A structural study of these oligosaccharides by one- and two-dimensional NMR and methylation analyses indicated the presence of extended oligosaccharide side chains with two consecutive beta-1,2-linked mannose units at the nonreducing terminal of alpha-linked oligosaccharides. The linkage sequence present in this mannan, Man beta 1-->2Man alpha 1-->3Man alpha-->, has also been found in the mannan of Saccharomyces kluyveri but not in the mannan of Candida species. Furthermore, these oligosaccharides are branched at position 6 of the 3-O-substituted mannose units as follows. (Carbohydrate sequence in text) Structure 1 and (Carbohydrate sequence in text) Structure 2 The H-1 signals of the mannose units substituted by a 3,6-di-O-substituted unit showed a significant upfield shift (delta delta = 0.04-0.08 ppm) due to a steric effect. The inhibition of an enzyme-linked immunosorbent assay between the mannan of C. guilliermondii and factor 9 serum with oligosaccharides obtained from several mannans indicated that only the oligosaccharides with the above structure were active, suggesting that these correspond to the epitope of antigenic factor 9.

Antigens, Fungal↗
PubMed1996

Preoperative diagnosis of intratemporal facial nerve tumor: high-resolution CT and otoscopic findings in 4 cases.

Four cases of facial nerve tumor were treated in our clinic during the past 16 years, one of which was a recurrence 12 years after the resection. Another case presented with relapsing facial palsy of sudden onset. The others presented with slowly progressive facial palsy. In each of the four cases, the horizontal and vertical portions were included in the tumor extension, and a mass was revealed in the posterior tympanic cavity by use of otoscopy. High-resolution CT, performed in all but the earliest case, proved to be the most valuable diagnostic tool, indicating the anatomical correlation of the tumor with the facial canal. With the diagnosis preoperatively established, facial reanimation procedure could be applied immediately after the tumor resection except in the recurrent case.

Cranial Nerve Neoplasms↗
PubMed1996

Antigenicity of cell wall mannans of Candida albicans NIH B-792 (serotype B) strain cells cultured at high temperature in yeast extract-containing sabouraud liquid medium.

Cultivation of Candida albicans NIH B-792 (serotype B) at high temperature (37 degrees C) for 48 h in yeast extract-containing Sabouraud liquid medium (YSLM) provided the following findings in comparison with the findings obtained after incubation at 27 degrees C. Growth of the blastoconidia of this strain was decreased, with a dry weight of 9%, and the cells were deficient in cytokinesis. The cells did not undergo agglutination with serum factor 5 from a commercially available serum factor kit (Candida Check). Mannan (B-37-M) obtained from the cells cultured at 37 degrees C had partially lost its reactivity against serum factor 4 and lost most of its reactivity against serum factor 5 in an enzyme-linked immunosorbent assay (ELISA) in contrast to that (B-27-M) at 27 degrees C. Both cells and mannan prepared by cultivation first at 37 degrees C and then at 27 degrees C entirely recovered their reactivities with serum factors 4 and 5. 1H-nuclear magnetic resonance analysis also revealed that B-37-M had lost a beta-1,2-linked mannopyranose unit and retained a phosphate group. Similar changes were observed in the three other serotype B strains used in the study. The beta-1,2-linked mannooligosaccharides longer than mannotetraose were not included among the products released from B-37-M by mild acid treatment. The results of the inhibition ELISA with a series of beta-1,2-linked mannooligosaccharides from biose to octaose (M2 to M8, respectively) showed that the reactivity against serum factor 4 was inhibited most strongly by the oligosaccharides M4 to M8 and that the reactivity against serum factor 5 was inhibited completely by relatively longer oligosaccharides, M5 to M8, indicating their participation as the antigenic factor 5 epitopes.

Agglutination Tests↗
PubMed1996

[Influence of total parenteral nutrition in immature rats: effect of glutamine infusion on bowel integrity].

Total parenteral nutrition (TPN) is accepted important therapeutic adjunct in spite of many complications for management of pediatric patients who aren't allowed to eat. Recently, bacterial translocation was added to the complications of TPN. The purpose of this study was to examine the influence of TPN on the gut in immature rats. 65g rats were randomized to one of four groups: Group C (control) received food and water ad libitum. Group P (TPN) received standard TPN solution. Group G (TPN+GLT) received glutamine (7g/400ml of TPN). Group E (TPN with enhanced protein) received TPN solution with enhanced protein (18.5g/400ml), without GLT. CFU of E. coli in mesenteric lymphnodes was significantly higher in group P than in other 3 groups at 5 days. Hepatic glutathione was significantly higher in group G than in group P and group E at 7 days. Weight of wet intestine was the highest in group C in all groups, and significantly higher in group G than in group P and group E at 3 and 7 days. Mucosal protein of group C was the highest of those of 4 groups. That of group G was significantly higher than those of group P and G in 5 and 7 days. Mucosal thickness and villous height were the highest in group C in 4 groups. Mucosal thickness was significantly higher in group G than in group P and group E at 5 and 7 days. Villous height was significantly higher in group G P and group E at all days. These results suggest that TPN promotes intestinal atrophy from early days after TPN in immature rats, that glutamine might play a role in maintenance of structural integrity of intestine, and that glutamine would prevent the bacterial translocation.

Animals↗
PubMed1996

[A case of coronary perforation after directional coronary atherectomy].

Directional coronary atherectomy was performed on a 69-year-old female with angina pectoris. She suffered from coronary perforation as a result of cardiac tamponade and shock. Pericardial drainage and hemostasis were performed immediately using a perfusion catheter. The patient was transferred to the operating room for perforation repair and coronary artery bypass grafting to the distal portion of the left anterior descending artery. The procedure was performed successfully. Although acute coronary perforation associated with directional coronary atherectomy is rare, it can be managed temporarily by a perfusion catheter and we successfully performed coronary artery bypass grafting.

Aged↗
PubMed1996

Therapeutic effect of the quinolone prodrug prulifloxacin against experimental urinary tract infections in mice.

The in vitro antibacterial activity of prulifloxacin (CAS 123447-62-1, NM441), a new quinoline prodrug, against clinical isolates from urinary tract infections was investigated. In addition, it was compared with ofloxacin (CAS 82419-36-1), levofloxacin (CAS 100986-85-4), ciprofloxacin urinary tract infections in mice, as well as its pharmacokinetics. 1. The antibacterial activity of NM394 (6-fluoro-1-methyl-4-oxo-7-(1-piperazinyl)-4H-[1,3]thiazeto[3,2- a]quinoline-3-carboxylic acid), an active metabolite of prulifloxacin, against gram-positive clinical isolates was inferior to that of levofloxacin and tosufloxacin, and equal to that of ofloxacin and ciprofloxacin. Against gram-negative clinical isolates, the activity of NM394 was superior to that of the reference drugs. 2. The therapeutic effect of prulifloxacin on experimental urinary tract infection with Escherichia coli in mice was equal to that of tosufloxacin and ciprofloxacin and superior to that of ofloxacin and levofloxacin. Its therapeutic effect on Pseudomonas aeruginosa infection was equal to that of tosufloxacin and ciprofloxacin, and superior to that of ofloxacin. Against urinary tract infection with olfloxacin-resistant Enterobacter cloacae, prulifloxacin was the most effective of all the drugs tested. 3. The maximal serum concentration of prulifloxacin was slightly higher than that of ciprofloxacin, and the area under the curve (AUC) for prulifloxacin was 1/4 that of ofloxacin, levofloxacin and tosufloxacin. The maximal concentration and AUC of prulifloxacin in lung and kidney were slightly higher than the corresponding values for ciprofloxacin but only 1/2 to 1/4 of the values for ofloxacin, levofloxacin and tosufloxacin. In conclusion, prulifloxacin (NM394) showed potent antibacterial activity against clinical isolates and potent therapeutic efficacy against experimental infection in spite of its lower AUCs compared with the reference drugs. These findings suggest that prulifloxacin may be a useful drug in the treatment of urinary tract infections.

Animals↗
PubMed1995

Detection of beta-1,2-mannosyltransferase in Candida albicans cells.

A particulate insoluble fraction from Candida albicans J-1012 (serotype A) strain cells was obtained as the residue after extracting a 105,000 x g pellet of cell homogenate with 1% Triton X-100. Incubation of this fraction with a mannopentaose, Man beta 1-->2Man alpha 1-->(2Man alpha 1-->)(2)2Man (alpha beta Man5), in the presence of GDP-mannose followed by high performance liquid chromatography showed the formation of a mannohexaose. Analysis of the product by 1H NMR indicates that alpha beta Man5 was changed to Man beta 1-->2Man beta 1-->2Man alpha 1-->(2Man alpha 1-->)2 2Man (alpha beta Man6). This beta-1,2-mannosyltransferase (ManTase) II activity was completely inhibited by Zn2+ and was not restored by the addition of EDTA. The corresponding enzyme fraction from C. albicans NIH B-792 (serotype B) strain cells, the mannan of which does not possess both the alpha beta Man5 and alpha beta Man6 side chains, also exhibited the same beta-1,2-ManTase II activity.

Candida albicans↗
PubMed1995

Dental health indicator based on a questionnaire.

Dentistry has lacked an effective indicator of the impact of dental problems on a person's daily life. Subjective factors in dental health need to be included in order to improve current indicators. The purpose of this research was to develop a new type of indicator recorded from a questionnaire which takes account of subjective factors in dental health. The indicator we constructed has the following advantages. 1. Calculation process is simple in practice. 2. The indicator values range from 0 to 100, with values closer to 100 indicating a more favorable condition for the individual. 3. The distribution of indicator values is similar to the normal distribution. 4. The score of each item is reflected on the indicator, suggesting the individual's characteristics in terms of dental health. 5. Although it is principally an indicator for individuals, it can also be applied to groups. This study will also provide a model for the preparation of a dental health indicator.

Adult↗
PubMed1994

Temperature-dependent change of serological specificity of Candida albicans NIH A-207 cells cultured in yeast extract-added Sabouraud liquid medium: disappearance of surface antigenic factors 4, 5, and 6 at high temperature.

The cells of Candida albicans NIH A-207 strain (A-strain) cultivated in YSLM at high temperatures (37 and 40 degrees C) did not undergo agglutination with the factor sera 4, 5, and 6 in a commercially available factor serum kit, 'Candida Check', and formed a grape-like shape. The mannans isolated from the cells had lost their reactivity against the factor sera in ELISA. It was also revealed by 1H NMR analysis that the mannans contained neither a phosphate group nor a beta-1,2-linked mannopyranose unit, although these mannans increased the non-reducing terminal alpha-1,3-linked mannopyranose unit. The cells and the mannans prepared by cultivation at such high temperatures followed by 27 degrees C in the same medium entirely recovered the reactivity with the factor sera.

Agglutination Tests↗
PubMed1994

Anti-oral microbial activity of isoflavonoids in root bark of Ormosia monosperma.

From the root bark of Ormosia monosperma, 10 isoflavonoids including two new compounds 7,4'-dihydroxy-6",6"-dimethylpyrano-(2",3":5,6)-8-(3-methyl-1,3- butadienyl)isoflavone, named ormosidin, and dalbergion 4'-O-beta-D-glucopyranoside, were isolated. These structures were confirmed by spectroscopic analysis. 2,3-Dihydroauriculatin, one of the compounds isolated, showed moderate activities against oral-microbial organisms (Streptococcus mutans, Prophyromonas gingivalis and Actinomyces actinomycetemcomitans).

Anti-Infective Agents↗
PubMed1993

High frequency of etoposide (VP-16)-related secondary leukemia in children with non-Hodgkin's lymphoma.

PATIENTS AND METHODS: We report patients who were treated for non-Hodgkin's lymphoma (NHL) or Ki-1 antigen-positive (Ki-1) lymphoma with a T-8801 protocol that included etoposide (VP-16) and behenoylcytosine arabinoside. RESULTS: Secondary acute myeloid leukemia (AML) developed in 5 of 38 NHL and Ki-1 lymphoma patients, and the cumulative risk at 4 years was 18.4%. The median time from the initiation of the chemotherapy to the development of AML was 21 months (range, 13-30). Four patients had a FAB M5 morphology, and one had FAB M2. In four of five examined cases, chromosomal alterations involving the long arm of chromosome 11 were demonstrated at the time of development of AML. None of the 46 NHL patients who we treated with another protocol (B-8801), using significantly higher cumulative doses of VP-16 than in the case of the patients with T-8801 and a different schedule of VP-16 administration, developed secondary AML. CONCLUSIONS: The risk of secondary AML possibly related to the use of VP-16 given twice weekly.

Adolescent↗
PubMed1993

Prevalence of root caries in a Japanese adult population aged 20-59 years.

The purpose of the present study was to investigate the prevalence of root caries in an adult population in Japan. A total of 770 company employees aged 20-59 were examined in 1990. The subjects were all dentate and had 27.2 present teeth on the average. The proportion of gingival recession in this population ranged from 20.1% for the 20-29 year old group to 75.2% for the 50-59 year old group, with an average of 44.0%. In the present study, 3.2% of the subjects showed one or more active root caries. The prevalence of active root caries ranged from 0.4% at age 20-29 to 7.1% at age 50-59. The proportion of persons with active root caries and/or root fillings ranged from 1.3% at age 20-29 to 36.3% at age 50-59. The percentage of subjects with active and/or inactive caries and/or root fillings varied from 3.1% at age 20-29 to 43.4% at age 50-59. The prevalence of active root caries in the subjects at risk (with gingival recession) was 7.4% on the average and ranged from 2.2% at age 20-29 to 9.4% at age 50-59. The percentage of persons with active root caries and/or root fillings in the subjects at risk ranged from 6.7% at age 20-29 to 48.2% at age 50-59. The mean number of teeth with active root lesions was 0.09 per person, and the mean number of teeth with root fillings was 1.25 at age 50-59.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Site-specific CPITN score and periodontal disease activity assessed by the paper BANA assay.

The purpose of this study was to examine the association between site-specific periodontal conditions assessed by CPITN and BANA test results. A total of 161 Japanese company employees aged 18-59 were examined for their periodontal conditions at mesio-buccal and mid-lingual sites of the maxillary right and mandibular left first molars using CPITN. Code 2 (calculus) was divided into Code 2+ and Code 2- by the presence or absence of bleeding. Plaque samples were collected from the examined sites with a scaler and placed on BANA reagent cards. The results indicated a close relationship between site-specific CPITN Codes and the BANA test results except at sites designated Code 2-. The proportion of sites with strong-positive reactions were 19.0% for Code 0, 21.4% for Code 2-, 29.9% for Code 1, 37.0% for Code 2+ and 50.0% for Code 3. These data indicated that the teeth given higher CPITN Codes tend to have higher risks for periodontal disease. From these results, it was concluded that the site-specific CPITN score is a good indicator of periodontal disease activity and that a higher priority for treatment should be given to the sites with pocket formation (Code 3 and Code 4) and/or gingival bleeding (Code 1 and Code 2+).

Adolescent↗