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Toshihiko Kato

Publications and source records attributed to Toshihiko Kato.

11 recordsLinked to original sources
PubMed2006

Evaluation of influenza vaccination in health-care workers, using rapid antigen detection test.

A study was conducted to assess the effectiveness of trivalent influenza vaccine in preventing influenza and reducing absenteeism in health-care workers of Gifu Red Cross Hospital during the 2002-2003 influenza season. Questionnaires were distributed to 370 health-care workers, and 366 were returned showing that 237 had received influenza vaccine and 129 were unvaccinated. The criterion for influenza was febrile episodes with a positive reaction on a rapid antigen detection test. Among vaccine recipients, the number of influenza infections was 3.4 per 100 subjects, compared with 8.5 per 100 subjects in nonrecipients (P = 0.034), and the number of days absent from work per 100 subjects was 9.5, compared with 15.1 per 100 subjects in nonrecipients (P = 0.0003). The prevalence of adverse reactions to the vaccine was rather low. No serious adverse reactions were recorded and no one was absent from work because of adverse reactions. It is concluded that influenza vaccine is effective in preventing influenza and reducing absenteeism in health-care workers. The results of this study support recommendations for influenza vaccination in health-care workers.

Absenteeism↗
PubMed2006

Feeling of ear fullness in acute sensorineural hearing loss.

CONCLUSIONS: This study revealed two characteristic findings of the feeling of ear fullness (FEF) in acute sensorineural hearing loss (ASNHL). First, that the appearance of FEF was not associated with the auditory function on audiograms; and second, that the disappearance of FEF is clearly associated with the hearing prognosis. OBJECTIVE: FEF appears frequently in patients with ASNHL. However, there are few reports on this symptom and its mechanism has yet to be clarified. So we tried to investigate the character of FEF in ASNHL. PATIENTS AND METHODS: In this study, observations were made during the period from the first medical examination to 2 months after obtaining a steady audiogram on 227 ears from unilateral ASNHL cases, and the relationship between FEF and the audiograms was analyzed. RESULTS: The FEF prevalence at the first medical examination was about 80% for any audiogram shape or hearing threshold. Moreover, the better the hearing prognosis, the higher the improvement rate of FEF.

Acute Disease↗
PubMed2006

Prostate-specific antigen changes as a result of chlormadinone acetate administration to patients with benign prostatic hyperplasia: a retrospective multi-institutional study.

BACKGROUND: Antiandrogens used to treat benign prostatic hyperplasia (BPH) may affect the diagnosis of prostate cancer by decreasing serum prostate-specific antigen (PSA) values. We conducted a retrospective survey of BPH patients treated with chlormadinone acetate (CMA) and analysed the effect of CMA on their PSA values. METHODS: A chart-based, retrospective, multi-institutional survey of clinically diagnosed patients with BPH who had been treated with CMA (Prostal; 50 mg/day) was conducted. The patients were divided into three groups according to their baseline PSA values: <4 ng/mL, Group I; >or=4 ng/mL and <10 ng/mL, Group II; and >or=10 ng/mL, Group III. The changes in the PSA values from baseline after 16, 26, and 52 weeks of CMA therapy were predicted using a nonlinear regression model analysis. RESULTS: Data from 192 of the 303 enrolled patients were analysed. The predicted percent changes from baseline among all patients after 16, 26, and 52 weeks of treatment were -49.6%, -49.8%, and -49.9%, respectively. The corresponding values were -42.4%, -43.7% and -43.8% in Group I; -57.4%, -58.4% and -58.5% in Group II; and -50.6%, -50.6% and -50.6% in Group III, respectively. CONCLUSION: The PSA values reached a nadir, approximately -50% of the baseline, after 16 weeks of CMA administration and remained at the same level thereafter. When CMA is used to treat BPH patients, the possibility of abnormal increases in PSA associated with prostate cancer must be considered; if prostate cancer is suspected, prompt testing, including a biopsy, should be performed.

Aged↗
PubMed2005

Prognosis for sudden sensorineural hearing loss: a retrospective study using logistical regression analysis.

Sudden sensorineural hearing loss (SSNHL) remains a controversial problem with respect to etiology and the factors that might predict prognosis. We used logistical regression analysis to determine which factors are most strongly related to outcome for patients with SSNHL. In so doing, we employed a retrospective chart-review study. The study group consisted of 296 patients (296 ears). The outcome of SSNHL was cured (full recovery) in 64, recovered (partial recovery) in 175, and no change in 57. We performed separate analyses on those in the no-change and partial-recovery groups and on those in the no-change and full-recovery groups. The following factors were studied as explanatory variables: age; number of days until presentation; vestibular symptom; initial mean hearing level at 0.25 kHz, 0.5 kHz, 1 kHz, 2 kHz, and 4 kHz; and treatments (steroids, satellite ganglion block). In the first analysis, for patients in the no-change and recovered groups, the factors most strongly related to outcome were the number of days until presentation and age. The second analysis, for the nochange and cured groups, revealed that the number of days until presentation, vestibular symptom, age, and initial mean hearing level were most strongly related to outcome. Our results will increase the ability to predict the outcome for SSNHL.

Adolescent↗
PubMed2003

Human papillomavirus infection in actinic keratosis and bowen's disease: comparative study with expression of cell-cycle regulatory proteins p21(Waf1/Cip1), p53, PCNA, Ki-67, and Bcl-2 in positive and negative lesions.

We examined the presence of human papillomavirus (HPV) DNA in tissues of premalignant skin lesions, i.e., actinic keratosis (n = 13) and Bowen's disease (n = 62), taken from 69 Japanese immunocompetent and renal transplant recipient patients. Detection and typing of HPV DNA were performed using polymerase chain reaction (PCR) and sequence analysis or restriction fragment length polymorphism (RFLP) analysis, respectively. The positivity rates of HPV DNA in tissues of actinic keratosis and Bowen's disease were 77% and 65%, respectively. Twenty-seven HPV types were detected in 50 (67%) premalignant skin lesions, in which Z95963 (accession no. in the EMBL Databank), Z95968, AJ010823, and AJ000151 have been described as partial sequences of unknown HPV types. Furthermore, 2 unknown types, HPVX1 and HPVX2, were found in specimens of actinic keratosis. Sequence analysis showed that HPVX1 is related to HPV-37 (86.1% sequence homology) and that HPVX2 is related to HPV-38 (79.7%). These results indicate that various mucosal and epidermodysplasia verruciformis-related HPV types are associated with the pathogenesis of actinic keratosis and Bowen's disease. In addition, 24 specimens of HPV-positive or HPV-negative premalignant skin lesions were examined immunohistochemically for proliferating cells to determine biological differences between HPV-positive and HPV-negative lesions. Immunohistochemistry for p21(Waf1/Cip1), p53, proliferating cell nuclear antigen (PCNA), Ki-67, and Bcl-2 revealed that there was no significant difference in the cell proliferation activity between HPV-positive and HPV-negative lesions, suggesting that HPV infection alone does not induce cell proliferation in those lesions.

Adult↗
PubMed2003

Interlaboratory comparison in HercepTest assessment of HER2 protein status in invasive breast carcinoma fixed with various formalin-based fixatives.

Although formalin-based fixatives are used in pathologic laboratories, there is no strictly standardized fixation protocol in Japan. To examine interlaboratory variation caused by different conditions of fixation in the assessment of human epidermal growth factor receptor (HER) 2 status on pathologic tissues, 274 archival invasive breast carcinomas from 5 different laboratories were evaluated using the HercepTest. In 1 laboratory in which 10% neutral buffered formalin was used, as recommended by the manufacturer, the overexpression rate was 22.4% and fell within the statistical expected range (20%-30%) for HER2 overexpression in breast carcinomas. The overexpression rates in the other 4 laboratories, in which either 20% nonbuffered formalin or 15% neutral buffered formalin was used, were near the expected range for HER2 overexpression. To clarify the influence of prolonged formalin fixation on the HercepTest, we compared 1-day with 7-day fixations using 36 cases fixed with 20% nonbuffered formalin. Of the 36 cases, 7 showed 3+ staining with 1-day fixation and sustained the same scoring results with 7-day fixation, although the staining intensities in these cases were reduced with the prolonged fixation. These results indicated that the immunohistochemical assessment of HER2 status with the HercepTest was comparatively resistant to prolonged fixation conditions and provided stable staining results in positive cases, particularly 3+ patients.

Antibodies, Monoclonal↗
PubMed2003

Olfactory event-related potentials in normal subjects and patients with smell disorders.

We developed a device to record olfactory event-related potentials (OERP) from the human scalp. Methyl-cyclopentenolone was used as the odorant element. A total of 50 stimuli were delivered. Each stimulus lasted 0.5 sec and was delivered once every three inspirations. Normal OERPs were obtained with this device. The positive peak latencies were approximately 350 msec (P1) and 700 msec (P2), respectively. OERPs were also recorded in 40 patients with smell disorders. A positive response at about 300-400 msec was recorded in 7 patients (all females, 15-59 years old). The other 33 patients showed no response. The high potential area of this positive peak was located in the centro-occipital region of the scalp. The latency and the high potential area of this peak were similar to P1 recorded in normal subjects. The source of this peak was considered identical to that of P1. This may be a response to the trigeminal nerve during odor administration. P2 was not recorded in the patients with smell disorders. P2 may therefore be a response to the olfactory nerve.

Adolescent↗
PubMed2002

Identification of an endo-beta-N-acetylglucosaminidase gene in Caenorhabditis elegans and its expression in Escherichia coli.

We report the identification, molecular cloning, and characterization of an endo-beta-N-acetylglucosaminidase from the nematode Caenorhabditis elegans. A search of the C. elegans genome database revealed the existence of a gene exhibiting 34% identity to Mucor hiemalis (a fungus) endo-beta-N-acetylglucosaminidase (Endo-M). Actually, the C. elegans extract contained endo-beta-N-acetylglucosaminidase activity. The putative cDNA for the C. elegans endo-beta-N-acetylglucosaminidase (Endo-CE) was amplified by polymerase chain reaction from the Uni-ZAP XR library, cloned, and sequenced. The recombinant Endo-CE expressed in Escherichia coli exhibited substrate specificity mainly for high-mannose type oligosaccharides. Man(8)GlcNAc(2) was the best substrate for Endo-CE, and Man(3)GlcNAc(2) was also hydrolyzed. Biantennary complex type oligosaccharides were poor substrates, and triantennary complex substrates were not hydrolyzed. Its substrate specificity was similar to those of Endo-M and endo-beta-N-acetylglucosaminidase from hen oviduct. Endo-CE was confirmed to exhibit transglycosylation activity, as seen for some microbial endo-beta-N-acetylglucosaminidases. This is the first report of the molecular cloning of an endo-beta-N-acetylglucosaminidase gene from a multicellular organism, which shows the possibility of using this well-characterized nematode as a model system for elucidating the role of this enzyme.

Acetylglucosaminidase↗
PubMed2002

Electroencephalographic changes during intravenous olfactory stimulation in humans.

The intravenous olfaction test with thiamin propyl disulfide (TPD) is a simple procedure widely used in Japan. An olfactory stimulus is provided by intravenous injection of TPD (2 ml) over the course of 20 sec. The subject smells n-propyl mercaptan (a decomposition product of TPD discharged from the blood into alveoli) in expired air after treatment. In this preliminary study we recorded electroencephalograms (EEGs) in normal subjects during three stages: 1) eyes-closed rest (prestimulus), 2) olfactory sensation after TPD injection, and 3) disappearance of sensation. In each of these stages, we calculated and compared EEG powers according to the band components of each electrode position. This study was designed a) to evaluate by frequency analysis EEG changes during olfactory sensation after TPD injection, and b) to identify the most significant changes in EEG power according to frequency band and electrode location. During the intravenous olfactory stimulation, alpha 2 and beta 2 waves were activated over the frontal and temporal regions. After disappearance of olfactory sensation, these waves decreased in the same regions. EEG powers returned to prestimulus levels.

Adult↗
PubMed2002

[Magnetoencephalographic responses to odor and non-odor by fast Fourier transformation analysis in humans].

Magnetoencephalographic (MEG) responses to odor (amyl-acetate) and non-odor stimuli for 1 second were recorded in 9 healthy volunteers (right handed) with a dual 37-channel SQUID (Magnes, Bti Co.) and evaluated by fast Fourier transformation analysis, with the following results: 1. On MEG analysis, the spectral density increase in the left mid-central region at a frequency of 7 Hz was significantly greater in response to odor than in response to non-odor stimuli. This greater increase is apparently related to the presence of the odor perception mechanism in the orbital frontal area, a major center of the olfactory system. 2. Both increased and decreased spectral density areas at a frequency of 8 Hz were observed over the right hemisphere when no stimuli was compared with non-odor and no stimulus compared with odor. These changes may reflect a high level of vigilance caused by stimulation. 3. When no stimulus was compared with non-odor stimulation, a significant spectral density increase at a frequency of 11 Hz was noted. Similar trends were observed at frequencies of 11 and 12 Hz when no stimulus was compared with odor. These findings indicated increased attention in response to random presentation of odor and non-odor. 4. Significant differences at frequencies from 14 to 24 Hz were noted in the contralateral hemisphere when no stimulus was compared with odor stimuli. MEG spectral densities at 21 and 22 Hz were also noted in the contralateral hemisphere when no stimulus was compared with non-odor stimulus. These differences apparently arise from the response of the somato-sensory cortex to non-odor stimuli and amyl-acetate. Alternation of MEG spectral densities at frequencies from 14 to 17 Hz and 23 to 24 Hz in the left hemisphere was noted when no stimulus was compared with non-odor and no stimulus was compared with odor. These results appear to be related to "emotions" of pleasantness and unpleasantness evoked by non-odor and odor.

Adult↗