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Y Iinuma

Publications and source records attributed to Y Iinuma.

At least 55 records · Page 3Linked to original sources

[Evaluation of COBAS CORE anti-HIV-1/HIV-2 EIA DAGS for the detection of antibodies to HIV by COBAS CORE].

COBAS CORE Anti-HIV-1/HIV-2 EIA DAGS (CORE HIV-1/2) for the detection of antibodies to HIV-1 and HIV-2 was evaluated by a fully automated immunoassay system, COBAS CORE II (Roche Diagnostics K.K.). The sensitivity of CORE HIV-1/2 was assessed in comparison with PA1/2, Enzygnost, VIDAS and AxSYM by testing serial two-fold dilutions of HIV-1 and HIV-2 sera. CORE HIV-1/2 showed the highest sensitivity than other methods. The agreements of the results of anti-HIV antibodies determinations between the CORE HIV-1/2 and other methods, PA1/2, Enzygnost, VIDAS, and AxSYM, were 99.4%, 100%, 100%, and 99.7%, respectively in the tests for anti-HIV-1 antibody. In the tests for anti-HIV-2, all results were agreed at 100%. Discrepant samples which showed a negative by CORE HIV-1/2 and a positive by PA1/2 and AxSYM were clearly negative of anti-HIV-1 antibody by p24 ACA, PCR, Western blot, and continuous clinical studies. This assay showed excellent coefficients of variation for both within-run and day to day precision. The determination of anti-HIV antibodies was not interfered with hemoglobin, bilirubin, and chylemia. We conclude that the excellent specificity and sensitivity of the CORE HIV-1/2 make the CORE HIV-1/2 a suitable method for diagnosis of HIV-1 and HIV-2 infections in clinical laboratories.

Evaluation Studies as Topic↗

[Multicenter evaluation of broth microdilution test, BrothMIC MTB, to determine minimum inhibitory concentrations (MICs) of antimicrobial agents for Mycobacterium tuberculosis--evaluation of interlaboratory precision and interpretive compatibility with agar proportion method].

A newly developed microdilution antimycobacterial susceptibility test, BrothMIC MTB (Kyokuto Pharmaceutical Industrial Co., Ltd., Tokyo, Japan) to determine minimum inhibitory concentrations (MICs) was evaluated at multisites. The test method utilizes air-dried microplates containing serially diluted antimicrobial agents and the modified Middlebrook 7H9 broth. The eight antimycobacterial agents tested were rifampicin, isoniazid, ethambutol, streptomycin, kanamycin, levofloxacin, sparfloxacin and ciprofloxacin. The test plates were reconstituted by inoculation of 0.2 ml of cell suspensions (6 x 10(5) cells/ml) and were incubated at 36 degrees C in 5% to 10% CO2. The growth endpoints were visually read after 7-day and 10-day incubations. The reproducibility was evaluated with the four reference strains of Mycobacterium tuberculosis, and were compared with the agar proportion method described in the National Committee for Clinical Laboratory Standards (NCCLS) M24-T. Of the 1,022 testings of the reference strains, 1,020 (99.8%) of the MICs read after 7-day incubation fell within 3 log2 dilutions. The growth endpoints read after 7-day and 10-day incubations gave equal MIC ranges for the respective agents. The results obtained by the BrothMIC MTB for 93 clinical isolates of M. tuberculosis compared well with those determined by the NCCLS method with 98% to 99% agreements, except for ethambutol. According to the comparative analysis with the agar proportion method, the interpretive MIC breakpoints to discriminate between the isolates susceptible and resistant against the respective agents were proposed. In conclusion, this newly developed microdilution test for M. tuberculosis is a practical, rapid, quantitative, nonradiometric alternative for the determination of MICs in clinical mycobacteriology laboratories.

Antitubercular Agents↗

Diagnostic value of the Amplicor PCR assay for initial diagnosis and assessment of treatment response for pulmonary tuberculosis.

We evaluated the Amplicor PCR assay as an initial diagnostic tool on the basis of clinical diagnosis, and assessed this assay as a follow-up test for patients with pulmonary tuberculosis during chemotherapy. Of the 208 specimens from 155 patients who were bacteriologically and/or clinically diagnosed with active tuberculosis before chemotherapy, 144 were Amplicor PCR-positive (sensitivity, 69.2%), which was equal to the results of culturing. Among 89 specimens which showed positive results by smear and culturing, the Amplicor PCR assay detected 87 (97.8%), whereas among 55 specimens which showed smear-negative but culture-positive results, the Amplicor PCR assay detected 46 (83.6 %)(P= 0.003). No false positive results were found in the two systems (specificity, 100%, 120/120). The Amplicor PCR assay was also evaluated as a follow-up test using 926 specimens from 207 patients receiving active tuberculosis chemotherapy. Among 433 specimens which showed Amplicor-PCR positive, 222 (51.3%) were culture-negative. On the other hand, among 233 culture-positive specimens, only 12 (5.2%) were Amplicor PCR-negative. Therefore, this assay is useful for the rapid diagnosis of tuberculosis. The duration of Amplicor PCR-positive after culture-negative conversion was significantly associated with the presence of cavitary lesion, smear-positive specimens before treatment, and smear-positive specimens with negative cultures during chemotherapy.

Antitubercular Agents↗

A clinical and bacteriologic investigation of invasive streptococcal infections in Japan on the basis of serotypes, toxin production, and genomic DNA fingerprints.

In a survey of invasive streptococcal infections in Japan, we analyzed isolates of Streptococcus pyogenes collected between 1992 and 1994. Genomic DNA fingerprints produced by pulsed-field gel electrophoresis (PFGE) were compared by computer-assisted analysis. Conventional serologic M types were subdivided into PFGE types showing close genetic similarity. Among the 42 isolates from patients with invasive diseases, 16 PFGE types were identified and genetic diversity was clearly demonstrated. Identical fingerprints were observed in both invasive and noninvasive isolates. Only 43% of invasive isolates produced streptococcal pyrogenic exotoxin A (SPE A), and 31% did not contain the speA gene. These findings suggest that the dissemination of a specific clone is not sufficient to explain all cases of these diseases in Japan and pose a question as to the role of SPE A as a major virulent factor. Bacterial factors other than SPE A and host factors should be considered in evaluation of the pathogenesis of the diseases.

Antibodies, Bacterial↗

Diagnostic value of the strand displacement amplification method compared to those of Roche Amplicor PCR and culture for detecting mycobacteria in sputum samples.

We compared the ability of the semiautomated BDProbeTec-SDA system, which uses the strand displacement amplification (SDA) method, with that of the Roche Amplicor-PCR system and the Septi-Chek AFB culture system to directly detect Mycobacterium tuberculosis complex (MTB) and other mycobacteria in sputum samples. A total of 530 sputum samples from 299 patients were examined in this study. Of the 530 samples, 129 were culture positive for acid-fast bacilli with the Septi-Chek AFB system; 95 for MTB, 29 for M. avium-M. intracellulare complex (MAC), and 5 for other mycobacteria. The BDProbeTec-SDA system detected 90 of the 95 samples culture positive for MTB (sensitivity, 94.7%), and the Amplicor-PCR system detected 85 of the 95 samples culture positive for MTB (sensitivity, 89.5%). The specificity of each system, based on the clinical diagnosis, was 99.8% for SDA and 100% for PCR, respectively. Among the 29 samples culture positive for MAC, the BDProbeTec-SDA system detected MAC in 24 samples (sensitivity, 82.8%), whereas the Amplicor-PCR system detected MAC in 23 samples (sensitivity, 79.3%). The specificities of the systems were 98.3 and 100%, respectively. The high degrees of sensitivity and specificity of the BDProbeTec-SDA system suggest that it should be very useful in clinical laboratories for the rapid detection of mycobacteria in sputum samples.

Bacteriological Techniques↗

Large-restriction-fragment analysis of Mycobacterium kansasii genomic DNA and its application in molecular typing.

Large-restriction-fragment (LRF) polymorphisms in Mycobacterium kansasii isolates from 84 patients with bronchopulmonary infections in Japan between the 1960s and 1995 were studied by pulsed-field gel electrophoresis (PFGE). Chromosomal fragments digested with VspI were most suitable for PFGE separation of 16 to 21 fragments of between 40 and 550 kbp. All 84 isolates and the type strain M. kansasii ATCC 12478 were successfully typed by LRF analysis with VspI digestion. Twenty-one distinctive LRF types were identified, and the LRF patterns tested over time were reproducible and stable. A computer-assisted dendrogram of the percent similarity demonstrated that isolates of 18 LRF types had relatively close genetic relatedness, while isolates of the remaining 3 types showed divergence. Sequence analysis of the 16S rRNA gene in the isolates showing divergent genetic relatedness revealed a sequence identical to that of a previously reported subspecies of M. kansasii. In the Chugoku district of Japan, 11 cases of M. kansasii infection which occurred in workers in a coastal industrial zone between 1982 and 1993 were caused by one particular strain tentatively named LRF type M. When both detailed demographic data for the patients and ecologic data for the M. kansasii isolates are obtained, LRF typing may be of potential use for investigating the source and transmission of M. kansasii infection.

Bacterial Typing Techniques↗

Exfoliative toxin detection using reversed passive latex agglutination: clinical and epidemiologic applications.

A rapid and simple method for detecting exfoliative toxin serotypes A and B from clinical isolates has been developed as a test kit (EXT-RPLA; Denka Seiken Co. Ltd., Niigata, Japan). This method is based on reversed passive latex agglutination. The detection limit of the EXT-RPLA observed for purified exfoliative toxin serotypes A and B was 1 ng/ml. We evaluated the clinical and epidemiologic uses of the EXT-RPLA. A total of 381 isolates of Staphylococcus aureus, 292 from various clinical specimens and 89 from the skin of dermatologic patients, were studied. The EXT-RPLA detected 19 exfoliative toxin producers, including 16 serotype A producers and 3 serotype B producers, but no double producers. The sensitivity and specificity of the EXT-RPLA were confirmed by the newborn mouse bioassay and a PCR assay for the structural genes for exfoliative toxin serotypes A and B (eta and etb, respectively). The overall positivity rate of exfoliative toxin producers was 5.0% (19 of 381), including 16 serotype A isolates and 3 serotype B isolates. Of the 89 isolates from the skin of dermatologic patients, 12 (13.5%) were positive for exfoliative toxin production. Only 2 (1.3%) of the 153 methicillin-resistant S. aureus isolates produced exfoliative toxin, while 17 (7.5%) of the 228 methicillin-sensitive isolates produced exfoliative toxin. The EXT-RPLA assay is a simple and reliable method for detecting exfoliative toxin, and we recommend its use for the rapid diagnosis of staphylococcal scalded skin syndrome. We also recommend its use for detection of this syndrome so that effective control measures can be taken against the spread of this syndrome.

Agglutination Tests↗

Mycobacterium growth indicator tube testing in conjunction with the AccuProbe or the AMPLICOR-PCR assay for detecting and identifying mycobacteria from sputum samples.

We have compared the ability of the Mycobacterium Growth Indicator Tube (MGIT) system, a new culture method with an oxygen-sensitive fluorescent sensor, to recover mycobacteria from sputum samples with the abilities of egg-based medium and the Septi-Chek AFB system. We have also assessed the clinical utility of the AccuProbe or the AMPLICOR-PCR assay to directly identify Mycobacterium tuberculosis complex and M. avium-M. intracellulare complex (MAC) from positive MGITs. From 382 sputum samples, 99 isolates of M. tuberculosis complex and 20 isolates of MAC were recovered. The MGIT system had the highest recovery rates for M. tuberculosis complex (97.0%) and MAC (100%), compared to recovery rates of 51.5 and 65.0%, respectively, with the egg-based medium and 81.8 and 85.0%, respectively, with the Septi-Chek AFB system. The shortest recovery times were also achieved with the MGIT system: 16.6 days for M. tuberculosis complex and 12.0 days for MAC, compared to 27.1 and 20.1 days, respectively, with the egg-based medium and 21.4 and 13.2 days, respectively, with the Septi-Chek AFB system. The AccuProbe identified 74 (77.1%) of the 96 M. tuberculosis complex-positive MGITs and 17 (85.0%) of the 20 MAC-positive vials. The AMPLICOR system correctly identified 94 (97.9%) of the 96 M. tuberculosis complex-positive MGITs and all 20 MAC-positive vials. Therefore, the MGIT system used in conjunction with the AMPLICOR system is a rapid and sensitive method for detecting and identifying M. tuberculosis complex and MAC isolates from sputum samples.

DNA, Bacterial↗

Campylobacter fetus subsp. fetus cholecystitis in a patient with advanced hepatocellular carcinoma.

Acute cholecystitis due to Campylobacter fetus subsp. fetus is very uncommon. We report a case of cholecystitis and obstructive jaundice in which cultured bile grew this organism. The patient had a 4-year history of hepatocellular carcinoma, resulting in common bile duct obstruction due to abdominal lymph node metastasis. Microscopic examination of her bile showed multiple Gram-negative curved organisms and C. fetus subsp. fetus was isolated under microaerophilic conditions. Therefore, we should be aware of this organism and use microaerophilic culture in association with the result of microscopic examination of bile specimens.

Campylobacter Infections↗

Types of methicillin-resistant Staphylococcus aureus associated with high mortality in patients with bacteremia.

Forty-seven strains of methicillin-resistant Staphylococcus aureus (MRSA) isolated from 47 patients with bacteremia were analyzed by chromosomal DNA digestion pattern using pulsed-field gel electrophoresis and evaluated for serological coagulase type, enterotoxin type, and toxic shock syndrome toxin-1 production. The mortality rate was significantly higher in the older patients (> or = 51 years of age) than in the younger patients (< or = 50 years of age) (50% vs. 4%, p = 0.0007). Methicillin-resistant Staphylococcus aureus strains of serological coagulase type II were more likely to be associated with mortality in older patients than were strains of the other types (p = 0.037).

Adolescent↗

Evaluation of Gen-Probe Amplified Mycobacterium Tuberculosis Direct Test and Roche PCR-microwell plate hybridization method (AMPLICOR MYCOBACTERIUM) for direct detection of mycobacteria.

We evaluated the clinical utility of an rRNA amplification-based Gen-Probe Amplified Mycobacterium Tuberculosis Direct Test (AMTD) system and a PCR-based Roche AMPLICOR MYCOBACTERIUM system for direct detection of Mycobacterium tuberculosis, M. avium, and M. intracellulare. Of the 422 sputum samples from 170 patients, 137 (121 of M. tuberculosis, 14 of M. avium-M. intracellulare complex [MAC], 2 of mycobacterium other than M. tuberculosis or MAC) were culture positive with the Septi-Chek AFB system. One sample of a contaminated culture results was excluded for further analyses. The AMTD system detected all of the 121 samples which grew M. tuberculosis (sensitivity, 100%). Of the 284 culture negative samples, 28 were positive by this system (specificity, 90.1%). After resolution of the discrepant samples, based on a positive history for culture of the patient, the specificity of this system increased to 99.3%. On the other hand, the AMPLICOR system gave a positive result for 132 out of the 135 culture positive samples for M. tuberculosis or MAC (sensitivity, 97.8%). Of the 284 culture-negative samples, 37 were positive by this system (specificity, 87.0%). The specificity for this system after resolution of the discrepant samples increased to 98.9%. The agreement between the results from the AMTD system and the AMPLICOR system was 98.7%. Both of the systems are highly sensitive and specific for detecting M. tuberculosis and/or MAC directly from sputum samples within hours, and they should be recommended for routine use in the clinical microbiology laboratory.

Bacteriological Techniques↗

Evaluation of immunochromatographic assay systems for rapid detection of hepatitis B surface antigen and antibody, Dainascreen HBsAg and Dainascreen Ausab.

We evaluated two immunochromatographic assays (ICAs), Dainascreen HBsAg for detecting human hepatitis hepatitis B surface antigen (HBsAg) and Dainascreen Ausab for detecting human hepatitis B surface antibody (anti-HBs) in human serum. The ICA systems are composed of a comb-shaped device that contains nitrocellulose strips on which complexes of HBsAg and anti-HBs can be visualized. The results can be read within 15 min of incubation. The limit of detection for HBsAg was 3.1 ng/ml and that for anti-HBs was 42 mIU/ml. Results of HBsAg detection agreed completely with those of conventional enzyme immunoassays (EIAs) and showed a 100% sensitivity (158 of 158 samples) and a 100% specificity (304 of 304 samples). The Dainascreen Ausab detected 184 of the 199 EIA-positive samples (sensitivity, 92.5%) and yielded 6 positive results among the 281 EIA-negative samples (specificity, 97.9%). The ICA systems are rapid and sensitive methods for detecting HBsAg and anti-HBs. They are low-cost systems that need no complex instrumentation for analysis and can be recommended for routine use in clinical microbiology laboratories.

Chromatography↗

Resulting long-term intestinal motility in dogs following construction of a reversed jejunal segment after extensive small bowel resection.

To evaluate the long-term function and effective motility of a reversed jejunal segment after extensive small bowel resection, the authors continuously measured postoperative bowel motility during interdigestive and postprandial periods in conscious dogs 6 to 10 months after surgery. The long-term findings were compared with previously reported short-term results measured 2 to 4 weeks after the operation. In the long-term follow-up dogs with a 20-cm reversed jejunal segment constructed after extensive (75% to 80%) small bowel resection, the fasting duodenal migrating myoelectric (or motor) complex (MMC) was often interrupted in the jejunum above the reversed segment, and did not migrate smoothly to the reversed segment or terminal ileum. The MMCs arising from the duodenum predominantly propagated to the ileum through the inherent anatomic continuity of the bowel. In addition, brief small discordant contractions were frequent in the reversed segment and the jejunum, above the proximal anastomosis. These findings are similar to those of the MMC propagation pattern noted 2 to 4 weeks after surgery. However, the postprandial duration without duodenal MMC activity was significantly shorter in the dogs with long-term follow-up than in those with short-term follow-up (both were longer than in control dogs). Marked dilatation of the jejunum and reversed jejunal segment was noted across the proximal anastomosis. These results suggest that the transit time and passage of intestinal contents can be delayed and stagnated for at least 10 months after extensive small bowel resection with a 20-cm reversed jejunal segment.(ABSTRACT TRUNCATED AT 250 WORDS)

Anastomosis, Surgical↗

An experience of cell sorting using samples isolated from paraffin-embedded tissue of neuroblastoma.

Flow cytometric DNA content analyses were performed on samples from 72 patients with neuroblastoma. Nuclear suspensions obtained from paraffin-embedded samples were prepared using the method described by Schutte et al. Determination of DNA ploidy was possible in 62 out of 72 patients. DNA diploidy was detected in 23 (37.1%) and DNA aneuploidy was found in 39 (62.9%) of these 62 patients. Cell sorting was performed on two peak areas of the DNA histogram of samples with aneuploidy. The sorted cells of the first peak area were composed of small round cells and were considered to be normal lymphocytes. The sorted cells of the second peak area were composed of relatively large cells with obvious nucleoli and were considered to be neuroblastoma cells. Thus, two cell components could be distinguished by cell sorting. It is concluded that cell sorting may be of benefit in giving detailed information about DNA histograms, even in samples obtained from paraffin-embedded tissue.

Cell Separation↗