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Y Osada

Publications and source records attributed to Y Osada.

At least 19 recordsLinked to original sources
PubMed2004

Glutathione S-transferase (GST) M1, T1 and N-acetyltransferase 2 (NAT2) polymorphisms and urothelial cancer risk with tobacco smoking.

The objective of this study was to examine the association between the genetic polymorphism of glutathione S-transferase (GST) M1, T1 and N-acetyltransferase 2 (NAT2) genes and urothelial cancer risk in relation to smoking status. In this study, 325 Japanese patients with urothelial transitional cell carcinoma and 325 healthy controls were compared for frequencies of GSTM1, T1 and NAT2 genotypes. The frequencies of GSTM1 null genotype and NAT2 slow genotype were significantly higher in the cases than in the controls (adjusted odds ratio (OR) 1.37, 95% confidence interval (CI) 1.01-1.87, adjusted OR 3.09, 95% CI 1.69-5.63, individually). Furthermore, the risk of GSTM1 null genotype and NAT2 slow genotype was higher among smokers (adjusted OR 1.48, 95% CI 1.01-2.15, adjusted OR 4.28, 95% CI 1.96-9.36, individually). The regression analysis of cancer risk as a function of the amount of smoking showed that the susceptibility of people who had GSTM1 null genotype increased from 45 pack-years, while the susceptibility of people with NAT2 intermediate or slow genotype increased rapidly from 25 pack-years, compared with non-smokers. A multiplicative interaction between NAT2 intermediate or slow genotype and pack-years of smoking was found (P<0.001), but GSTM1 null genotype was not (P=0.06). Our results indicate that the GSTM1 null genotype and NAT2 intermediate or slow genotype are associated with an increased risk of urothelial cancer in relation to smoking amounts. Furthermore, the interaction between NAT2 intermediate or slow genotype and pack-years of smoking has a strong impact on urothelial cancer.

Aged↗
PubMed2004

Infant schistosomiasis in Ghana: a survey in an irrigation community.

We used a rapid, visually read, field applicable monoclonal antibody (MoAb)-dipstick assay for specific diagnosis of urinary schistosomiasis together with microscopy to determine the prevalence of infant schistosomiasis in a community in the Awutu-Efutu Senya District in the Central Region of Ghana. The study group consisted of 97 infants (51 males and 46 females) aged 2 months to 5 years. A total of 75 of 97 (77.3%) subjects submitted stool samples; none had Schistosoma mansoni. Three individuals (3.1%) had hookworms but there were no other intestinal helminths. The urinary schistosomiasis prevalence by MoAb-dipstick (30%) was higher (P < 0.05) than that estimated by microscopy (11.2%). However, three of nine (33.3%) microscopically confirmed cases tested MoAb-dipstick positive after pre-treatment of the urine specimen with heat. The youngest infant to be found infected with S. haematobium microscopically was 4 months old. Fifteen of 71 S. haematobium egg negative individuals tested dipstick positive, giving a dipstick specificity of 78.9% as compared with microscopy as gold standard test. The relative sensitivity of the dipstick was 100%.

Antibodies, Monoclonal↗
PubMed2003

The antibody responses to adult-worm antigens of Schistosoma haematobium, among infected and resistant individuals from an endemic community in southern Ghana.

Antibody responses to antigens from adult Schistosoma haematobium were investigated in an endemic community in Ghana, using microplate-ELISA. The results of a survey of egg output in urine and of a questionnaire-based investigation of water-contact activities were used to select 'endemic normal' (EN) and patently infected (PI) individuals as subjects. The plasma levels of antibodies reacting with the adult-worm antigens were determined and compared and the correlations between these levels and the age, water-contact index and egg output of each subject were evaluated. Compared with the EN subjects, the PI generally had higher levels of anti-worm IgG and IgE but lower levels of anti-worm IgA. When the data for the EN and PI groups were combined, the levels of anti-worm IgG and IgE were found to be positively correlated with egg output and with each other. Whichever the antibody class considered, levels of anti-worm antibodies were never negatively correlated with egg output. These results indicate that anti-worm IgE and IgG could be used as markers to reflect current infection intensity, and that anti-worm antibodies may not act as protective antibodies in the natural course of urinary schistosomiasis.

Adult↗
PubMed2001

Correlation between Shine--Dalgarno sequence conservation and codon usage of bacterial genes.

In this study, we analyzed the correlation between codon usage bias and Shine--Dalgarno (SD) sequence conservation, using complete genome sequences of nine prokaryotes. For codon usage bias, we adopted the codon adaptation index (CAI), which is based on the codon usage preference of genes encoding ribosomal proteins, elongation factors, heat shock proteins, outer membrane proteins, and RNA polymerase subunit proteins. To compute SD sequence conservation, we used SD motif sequences predicted by Tompa and systematically aligned them with 5'UTR sequences. We found that there exists a clear correlation between the CAI values and SD sequence conservation in the genomes of Escherichia coli, Bacillus subtilis, Haemophilus influenzae, Archaeoglobus fulgidus, Methanobacterium thermoautotrophicum, and Methanococcus jannaschii, and no relationship is found in M. genitalium, M. pneumoniae, and Synechocystis. That is, genes with higher CAI values tend to have more conserved SD sequences than do genes with lower CAI values in these organisms. Some organisms, such as M. thermoautotrophicum, do not clearly show the correlation. The biological significance of these results is discussed in the context of the translation initiation process and translation efficiency.

Base Sequence↗
PubMed2001

Water-soluble covalent conjugates of bovine serum albumin with anionic poly(N-isopropyl-acrylamide) and their immunogenicity.

We have conjugated bovine serum albumin (BSA) to poly(N-isopropylacrylamide-co-acrylic acid) (poly(NIPAAm-AA)) by using water-soluble carbodiimide, and the effects of the bulk mass ratio of protein to polymer (r) on the formation of polymer-protein conjugates have been studied. HPLC, electrophoresis, viscosimetry and fluorescence spectroscopy suggest that the mode of covalent binding of BSA to poly(NIPAAm-AA) depends upon the weight concentration ratio (r) of BSA to poly(NIPAAm-AA). At r < or = 1, free poly(NIPAAm-AA) molecules coexist with conjugate, and when r reaches 1 the amount of free polymer is too small to be observed. It is shown that depending on the ratio r, two types of conjugate particles were formed: at r < 1, the protein molecules in the structure of conjugate particles are densely covered as a shell by polymer chain and practically "fenced off" from water environment; at r > 1 the conjugate-forming particles possess more friable structures in which protein molecules are practically exposed to the solvent. The complex formation involving electrostatic interactions between BSA and carbodiimide activated polymer are proposed as the driving force for the covalent binding of BSA to polymer macromolecules. The coil-globule transition of macromolecules in low and thermally induced precipitation in more concentrated solutions of bioconjugates was observed. The immunogenic properties of covalent conjugates of CP-BSA were investigated and the temperature-modulated solubility-immunogenicity alterations was analyzed. A single immunization of mice with conjugates at the thermally precipitating concentration without an adjuvant evoked increased specific immune response to BSA, which practically did not depend on the initial conjugation ratio of components. Such a modulated system is attractive for application as a novel immunogenic system in vaccine technology.

Acrylamides↗
PubMed2001

Fluorescence study of Cu(2+)-induced interaction between albumin and anionic polyelectrolytes.

The Cu(2+)-induced complex formation of bovine serum albumin (BSA) with anionic polyelectrolytes (PEs) (polyacrylic acid (PAA), poly(N-isopropylacrylamide) [poly[NIPAAm]], and copolymers of N-isopropylacrylamide (NIPAAm) and acrylic acid) in aqueous solution was studied by a fluorescence technique and high-performance liquid chromatography analysis. The character of the interactions depends on the monomer composition (r = [COOH]/[NIPAAm]), [Cu(2+)]/[PE], and [BSA]/[PE] ratios and solution pH. Two types of ternary polycomplex (polymer + Cu(2+) + BSA) particles are formed depending on the monomer composition r of the copolymer. At r from 1/3 to 1/1, the protein molecules in the structure of ternary polycomplex particles are densely covered by the shell of a polymer coil and practically "fenced off" from the water environment. At r > or = 3/1 ternary polycomplex PAA-Cu(2+)-BSA particles have more friable structures in which protein molecules are practically exposed to the solution. At low polymer concentration, an intrapolymer ternary polycomplex is formed. This complex aggregates to an interpolymer species upon increase in polymer concentration. Fluorescence data indicate that in ternary complex polymer interacts through Cu(2+) ions with BSA preferentially at the site close to the location of "cleft" tryptophan residue. This leads to static quenching of this tryptophan fluorescence. Cu(2+)-induced complex formation is an equilibrium reaction.

Animals↗
PubMed2001

Involvement of complement and fibronectin in eosinophil-mediated damage to Nippostrongylus brasiliensis larvae.

By using IL-5 transgenic mice, it has been shown that eosinophils might play a key role in elimination of larval stages of nematode infections. The present study was carried out to clarify molecular mechanisms involved in the eosinophil-mediated killing of Nippostrongylus brasiliensis larvae. The larvicidal activity was observed in the presence of normal serum in vitro. Electron microscopic observations revealed firm attachment of eosinophils to the cuticular surface of larvae, which was damaged by electron-dense materials released from eosinophils. The larvicidal activity was abrogated by heat- or zymosan-treatment of the serum, whereas depletion of IgG or IgM from the serum did not interfere with eosinophil adhesion and killing. Moreover, pretreatment of eosinophils with monoclonal antibodies against CD11b or VLA-4 inhibited the eosinophil-mediated killing of larvae. Immunofluorescent staining demonstrated the deposition of C3c and plasma fibronectin on the cuticle of the larvae. These results indicate that interactions between CD11b and VLA-4 and their respective counter-ligands deposited on the cuticle are essential in eosinophil-mediated adhesion and damage to larvae of N. brasiliensis.

Animals↗
PubMed2001

Protective immunity to Schistosoma japonicum infection depends on the balance of T helper cytokine responses in mice vaccinated with gamma-irradiated cercariae.

Although the strain difference in protection of mice to Schistosoma mansoni infection has been described, limited information is available in the case of Schistosoma japonicum. In the present study, we compared the protective immunity to S. japonicum infection and cytokine production in various strains of mice vaccinated with gamma-irradiated cercariae. A significant reduction in worm recovery was observed in male and female mice of DBA/2 at a 6-week interval between vaccination and a challenge infection, whereas vaccinated mice of C57BL/6, C57BL/10, (C57BL/6 x DBA/2) F1 (B6D2F1) and (C57BL/10 x DBA/2) F1 (B10D2F1) showed no detectable level of protection. No sex-linked difference in development of resistance was observed in any of the strains so far examined. Vaccination with gamma-irradiated cercariae twice with a 3-week interval also induced significant protection against a challenge infection in DBA/2 but not in BALB/c or C57BL/6 strains. Further studies demonstrated that spleen cells of vaccinated C57BL/6 mice produced lower levels of IFN-gamma compared to the cells of vaccinated BALB/c and DBA/2. On the other hand, production of IL-10 by spleen cells was relatively higher in BALB/c mice than in the other two strains. Macrophages that had been stimulated with spleen cell culture supernatants derived from vaccinated DBA/2 damaged schistosomula more effectively than cells stimulated with supernatants derived from the other strains. These results suggest that different levels of protection observed among strains of mice depend on the balance of cytokine responses which consequently activate or suppress macrophage-mediated damage to schistosomula.

Animals↗
PubMed2001

Prophylactic intravesical instillation of mitomycin C and cytosine arabinoside for prevention of recurrent bladder tumors following surgery for upper urinary tract tumors: a prospective randomized study.

BACKGROUND: A recurrence of bladder tumors following surgery for transitional cell carcinoma of the upper urinary tract is not rarely observed. A prospective randomized study was conducted to examine the significance of prophylactic intravesical instillation of mitomycin C (MMC) and cytosine arabinoside (Ara-C) to prevent recurrent bladder tumors after surgery for superficial transitional cell carcinoma of the upper urinary tract. METHODS: The patients were randomized into an instillation group, who received postoperative intravesical instillation of MMC (20 mg) and Ara-C (200 mg) 28 times over a period of 2 years, and a non-instillation group. The non-recurrence rate was then compared between the groups. RESULTS: Of the 27 patients registered, 25 patients (13 with instillation and 12 without instillation) were able to be evaluated, with a median follow-up period of 45 months. The non-recurrence rate of bladder tumors in the instillation group was higher than that in the non-instillation group. Although the difference was not statistically significant, the P-value (P = 0.079) demonstrated a strong trend. When any possible bias was allowed for a multivariate analysis, the difference was almost significant (P = 0.0567). No patients withdrew from this study due to any side-effects. CONCLUSION: The postoperative instillation of MMC and Ara-C may be a useful approach for reducing the recurrence of bladder tumors after surgery for upper urinary tract tumors.

Administration, Intravesical↗
PubMed2001

[An epidemiological study regarding the hearing acuity of residents in the area with high level of aircraft noise: results of hearing tests conducted in the vicinity of Kadena Air Base].

Hearing tests, primary and secondary, were conducted in two communities vicinal to Kadena US Air Base in Okinawa from May 1996 to July 1998. The noise exposure expressed in WECPNL as designated by the Defense Facilities Administration Agency ranged from 85 to 95 and above. A total of 2035 subjects aged between 25 and 69 years inclusive were considered eligible for inclusion in this study and among them 137 males and 206 females underwent the primary test. Before the test, subjects were asked about hearing difficulty, tinnitus, otological anamnesis and past experience of noise exposure at work and/or hobbies. The primary test was a pure tone audiometry using the ascending method of limits with 5 dB step at 7 test frequencies of 0.5 to 8 kHz. Forty individuals who were judged to have possible noise induced hearing loss were sent to Okinawa Chubu Hospital as subjects for the secondary test. The secondary test consisted of pure tone audiometry with 1 dB step at 9 test frequencies with the addition of 3 kHz and 6 kHz to the primary test frequencies, a Short Increment Sensitivity Index (SISI), test, tympanometry and audioscan audiometry. Based on test findings 12 subjects were considered to have noise induced hearing loss. The examiners interviewed the 12 subjects again to confirm that they had not experienced habitual or repeated intense noise exposure other than aircraft noise exposure around their homes. The geographical distribution of the subject's residences showed their proximity to the airfield, which strongly suggests that the cause of hearing loss may be exposure to aircraft noise from Kadena Air Base.

Adult↗
PubMed2001

[Small cell carcinoma of the prostate: a case report].

A 81-year-old man was admitted to our department with the chief complaints of pollakisuria and difficulty in voiding. He presented with increased serum PSA level (over 100 ng/ml). We performed biopsy of the prostate and found a moderately differentiated adenocarcinoma. Various urological examinations showed metastases to paraaortic lymph nodes and systemic bones. He was started-on hormonal therapy. Nine months from the start of hormonal therapy, this therapy was effective and the serum PSA level was decreased to 14 ng/ml. Thereafter, the serum PSA level and the tumor volume were increased and he died 29 months from the start of treatment. The autopsy revealed small cell carcinoma with adenocarcinoma of the prostate.

Aged↗
PubMed2001

[Diagnosis of prostate capsular invasion by pelvic magnetic resonance imaging and serum level of prostate specific antigen].

Transrectal ultrasonography (TRUS), computed tomography (CT), and magnetic resonance imaging (MRI) are employed to diagnose the clinical stage of prostate cancer. However, several cases are diagnosed as pathological stage pT3 after total prostatectomy. We investigated the accuracy of the evaluation of pathologic capsular penetration by preoperative pelvic MRI and preoperative serum PSA level and capsular penetration. The diagnostic accuracy of capsular penetration by MRI was 63.3%. On the other hand, the diagnostic accuracy of capsular penetration by preoperative PSA was 89.7% when its cut off value was 17 ng/ml. We conclude that preoperative serum PSA level could be more useful to diagnose accurately stage of prostate cancer than pelvic MRI.

Aged↗
PubMed2001

[Recurrence of vesicoureteral reflux detected 19 years after ureterocystoneostomy: a case report].

A 21-year-old male, who had been operated on for bilateral vesicoureteral refluxes (VURs) with bilateral ureterocystoneostomy (Politano-Leadbetter's method) 19 years before, was admitted to our hospital due to recurrent VUR. Since the former operation, he had undergone voiding cystography (VCUG) twice for two years, and no refluxes were found. Moreover, no evidence of upper urinary tract deterioration was found by either intravenous pyelography (IVP) or renal ultrasound scanning taken the year before this admission. Nineteen years after the operation, the dilation of the left lower ureter was found on IVP and, consequently, he suffered from pyelonephritis. The VCUG revealed the recurrence of left VUR. Because of his allergic reaction to collagen, we again performed left ureterocystoneostomy (Politano-Leadbetter's method). At three months postoperatively, there was no VUR found on VCUG.

Adult↗