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T Hagiwara

Publications and source records attributed to T Hagiwara.

At least 37 records · Page 2Linked to original sources
PubMed2000

Chlamydia pneumoniae serology: interlaboratory variation in microimmunofluorescence assay results.

The lack of standardization in chlamydia serology has made interpretation of published data difficult. This study was initiated to determine the extent of interlaboratory variation of microimmunofluorescence (MIF) test results for the serodiagnosis of Chlamydia pneumoniae infections. Identical panels of 22 sera were sent to 14 laboratories in eight countries for the determination of IgG and IgM antibodies by MIF. Although there was extensive variation in the numeric titer values, the overall percentage agreement with the reference standard titers from the University of Washington was 80%. For results by serodiagnostic category, the best agreement was for four-fold rise in IgG titers, while the lowest agreement was for negative or low IgG titers. Agreement for IgM titers was 50%-95%. Four laboratories failed to discern false-positive IgM titers possibly because of the presence of rheumatoid factor. Further studies are underway to determine the source of interlaboratory variation for the MIF test.

Antibodies, Bacterial↗
PubMed2000

[Comparison of the morphology and the reactivity of Chlamydia pneumoniae isolated in north-Kanto Area, Ibaraki Prefecture, Japan].

To compare the morphology among Chlamydia pneumoniae (C. pneumoniae), strain TW183 and strains which were isolated in the area of Kasumigaura, Ibaraki from 1992 to 1995. C. pneumoniae were infected on HL cell monolayers and cultured in 5% CO2 at 35.5 degrees C for about 60 hrs. The cells were harvested and fixed with 2.5% glutaraldehyde, and then the regular procedure for observation of Chlamydia in inclusion by transmission electron microscope was performed. Immunoblot assay was carried out by using highly and partially purified C. pneumoniae TW183 and 4 isolates with partial purification as antigens. The results were as follows: the shape of TW183 and the isolates included pear and round shapes, respectively. Immunoblotting profiles were the same in terms of band-formation patterns with the serum from a patient infected with C. pneumoniae. These results may indicate that the round shape of C. pneumoniae elementary body (EB) is predominantly pandemic in Japan, although pear-shaped EBs of C. pneumoniae were found in the neighboring prefecture of Chiba.

Child↗
PubMed2000

[Serovar distributions of cervical Chlamydia trachomatis isolated in Nagano Prefecture].

Between 1992 and 1998, serotyping of 82 Chlamydia trachomatis cervical isolates were examined by micro-IF method in Nagano Prefecture. Of these, 17 isolates (20.7%) were serovar E, 15 (18.3%) were serovar F, 14 (17.1%) were serovar D and 10 (12.2%) were serovar G, and the isolates typed these serovars were found to be 68.3% whole. Furthermore, serovars B (7.3%) and K (9.8%) were comparatively frequently found. From 1992 to 1994, the number of isolates of B-complex, intermediate and C-complex were 18, 17 and 6, respectively. On the other hand, from 1995 to 1998, the number of the isolates were 19, 8 and 14, respectively. The distribution of serovars of C. trachomatis tended to fluctuate from serovars D and E to F and G as the patients grew older. Moreover, serovar E isolates were only detected from patients less than 40 years old. Although most of the serovar I isolates were detected from the patients with vaginal discharge, the other isolates did not clearly indicate the relationship of serovars and clinical symptoms.

Adult↗
PubMed2000

Evaluation of a new amplified enzyme immunoassay (EIA) for the detection of Chlamydia trachomatis in male urine, female endocervical swab, and patient obtained vaginal swab specimens.

AIMS: To compare the performance of a new generation dual amplified enzyme immunoassay (EIA) with a molecular method for the diagnosis of Chlamydia trachomatis, using a range of urogenital samples, and to assess the reliability of testing self collected vaginal specimens compared with clinician collected vaginal specimens. METHODS: Two population groups were tested. For the first population group, first void urine samples were collected from 193 male patients with urethritis, and endocervical swabs were collected from 187 high risk commercial sex workers. All urine and endocervical specimens were tested by a conventional assay (IDEIA chlamydia), a new generation amplified immunoassay (IDEIA PCE chlamydia), and the Amplicor polymerase chain reaction (PCR). Discrepant results obtained among the three sample types were confirmed using a nested PCR test with a different plasmid target region. For the second population group, four swab specimens, including one patient obtained vaginal swab, two clinician obtained endocervical swabs, and one clinician obtained vaginal swab, were collected from 91 high risk sex workers. Self collected and clinician collected vaginal swabs were tested by IDEIA PCE chlamydia. Clinician obtained endocervical swabs were assayed by IDEIA PCE chlamydia and Amplicor PCR. RESULTS: The performance of the IDEIA PCE chlamydia test was comparable to that of the Amplicor PCR test when male urine and female endocervical swab specimens were analysed. The relative sensitivities of IDEIA, IDEIA PCE, and Amplicor PCR on male first void urine specimens were 79.3%, 91.4%, and 100%, respectively. The relative sensitivities of the three tests on female endocervical specimens were 85.0%, 95.0%, and 100%, respectively. The positivity rates for patient collected vaginal specimens and clinician collected vaginal specimens by IDEIA PCE were 25.2% and 23.1%, respectively, whereas those for clinician collected endocervical swabs by PCR and IDEIA PCE were both 27.5%. CONCLUSIONS: IDEIA PCE chlamydia is a lower cost but sensitive alternative test to PCR for testing male urine samples and female endocervical swabs. In addition, self collected or clinician collected vaginal specimens tested by IDEIA PCE chlamydia are a reliable alternative to analysing endocervical specimens.

Chlamydia Infections↗
PubMed1999

Molecular characterization of peptidylarginine deiminase in HL-60 cells induced by retinoic acid and 1alpha,25-dihydroxyvitamin D(3).

Three types of peptidylarginine deiminase (PAD), which converts a protein arginine residue to a citrulline residue, are widely distributed in animal tissues. Little is known about PAD of hemopoietic cells. We found that PAD activity in human myeloid leukemia HL-60 cells was induced with the granulocyte-inducing agents retinoic acid and dimethyl sulfoxide and with the monocyte-inducing agent 1alpha,25-dihydroxyvitamin D(3). We cloned and characterized a PAD cDNA from retinoic acid-induced cells. The cDNA was 2,238 base pairs long and encoded a 663-amino acid polypeptide. The HL-60 PAD had 50-55% amino acid sequence identities with the three known enzymes and 73% identity with the recently cloned keratinocyte PAD. The recombinant enzyme differs in kinetic properties from the known enzymes. Immunoblotting and Northern blotting with an antiserum against the enzyme and the cDNA, respectively, showed that a protein of approximately 67 kDa increased concomitantly with increase of mRNA of approximately 2.6 kilobases during granulocyte differentiation. During monocyte differentiation the same mRNA and protein increased as in granulocyte differentiation. Neither the enzyme activity nor the protein was found in macrophage-induced cells. These results suggested that expression of the PAD gene is tightly linked to myeloid differentiation.

Amino Acid Sequence↗
PubMed1999

Rat liver in vivo replicative DNA synthesis test for short-term prediction of nongenotoxic (Ames-negative) hepatocarcinogenicity: a collaborative study of the Nongenotoxic Carcinogen Study Group of Japan.

A collaborative study was conducted to evaluate whether a replicative DNA synthesis (RDS) test using the rat liver can detect nongenotoxic (Ames-negative) hepatocarcinogens with three or seven daily administrations at dose-levels effective in long-term bioassays. The assay methods were well-validated by the 14 participants. Of six compounds tested, carbon tetrachloride (50 and 100 mg/kg), clofibrate (125 and 250 mg/kg), diethylstilbestrol (0.125 and 0.25 mg/kg) and urethane (100 mg/kg) gave positive results, methyl carbamate (200 and 400 mg/kg) exerted equivocal effects, and D,L-ethionine (125 mg/kg) failed to elevate RDS. These findings suggest that the RDS test can detect many nongenotoxic rat hepatocarcinogens with short-term administration at dose-levels used in long-term bioassays.

Animals↗
PubMed1999

Paraquat myopathy: report on two suicide cases.

We describe two suicide cases in which old paraquat was ingested. In conjunction with lung involvement a pronounced degeneration was observed in skeletal muscle of one who died on the 14th day after the ingestion. The following sarcoplasmic or endoplasmic reticulum Ca2+ ATPase (SERCA) monoclonal antibodies were used for skeletal muscle fiber typing by an immunohistochemical method: NCL-SERCA1, reactive with type 2 fiber (fast-twitch), and NCL-SERCA2, reactive with type 1 fiber (slow-twitch). The examination revealed that the remarkably degenerated fibers belonged to type 1 muscle fibers. This case showed an abrupt increase of plasma CK levels (1796 mU/ml) on the fifth day after the ingestion. The authors presume that the damage to the skeletal muscle had occurred in this period. The degeneration of the muscle seemed to be attributable to the long retention of paraquat in the tissue because these findings were not observed in the other case who died on the fifth day. Paraquat-induced myopathy may develop in prolonged paraquat poisoning. The examination of CK levels in plasma will be useful for diagnosis of damage of skeletal muscle.

Aged↗
PubMed1999

Effect of salt addition on the fractal structure of aggregates formed by heating dilute BSA solutions.

The fractal dimension, Df, of aggregates in a dilute BSA system with added salt was evaluated by static light scattering (SLS). A fractal structure was observed for the system with NaCl addition. The values of Df increased with increasing heating time and ionic strength. The values of Df were larger than those (Df = 1.8 or 2.1) predicted by the conventional cluster-cluster aggregation model, probably due to a "restructuring" of aggregates during the aggregation process. On the other hand, a fractal structure was not apparent for the system with added CaCl2.

Animals↗
PubMed1999

Numerous huge iron particles appeared around micro blood vessels under intestinal epithelial cells in infant mice fed excess iron with protein.

In infant mice (2 weeks old) fed a diet with excess iron for one week, numerous huge iron particles around micro blood vessels under the basement membrane of intestinal epithelial cells were observed by electron microscopy. The frequency of occurrence of these particles (0.24 +/- 0.04 micron diameter) was markedly higher in mice fed a casein-based diet than in mice fed an amino acid-based diet. The quantity of these particles in both groups decreased in proportion to the term of 2 or 3 weeks. Changes in morphological features, such as opening of the intercellular junctions between intestinal epithelial cells, were also observed in these experimental groups. On the other hand, in mice fed the casein-based diet with excess iron, fat globules appeared in the intestinal epithelial tissue (intestinal epithelial cells, interstitial tissue, lympha) and the occurrence of these increased gradually in proportion to the term of feeding. These fat globules were not observed in mice fed the amino acid-based diet with excess iron. These phenomena might be elicited temporally in infant mice fed excess iron together with protein. The mechanisms of fat globule formation remain unclear.

Amino Acids↗
PubMed1998

Quantitative analysis of thrombopoietin receptors on human megakaryocytes.

Thrombopoietin (TPO), or c-MPL ligand, is the primary regulator of megakaryocyte and platelet production. TPO receptors expressed on human megakaryocytes derived from peripheral blood (PB) and cord blood (CB) progenitors cultured in the presence of TPO have now been analyzed quantitatively. Like those on human PB platelets, TPO receptors on the cultured megakaryocytes exhibited a molecular mass of approximately 80 kDa. Various characteristics of PB- and CB-derived megakaryocytes indicated that the former were more mature than the latter. Both PB- and CB-derived megakaryocytes expressed a single class of high-affinity TPO receptors, with 1933 +/- 772 (n = 3) and 184 +/- 48 (n = 4) sites per cell, respectively. These data indicate that the number of TPO receptors on human megakaryocytes increases with cell maturation.

Blood Platelets↗
PubMed1998

Determination of lycopene, alpha-carotene and beta-carotene in serum by liquid chromatography-atmospheric pressure chemical ionization mass spectrometry with selected-ion monitoring.

A selected-ion monitoring (SIM) determination of serum lycopene, alpha-carotene and beta-carotene by an atmospheric pressure chemical ionization mass spectrometry (APCI-MS) was developed. A large amount of serum cholesterols disturbed the SIM determination of carotenoids by contaminating the segment of interface with the LC-MS. Therefore, separation of carotenoids from the cholesterols was performed using a mixed solution of methanol and acetonitrile (70:30) as the mobile phase on a C18 column of mightsil ODS-5 (75 mm x 4.6 mm I.D.). The SIM determination was carried out by introducing only the peak portions of carotenoids and I.S. (squalene) by means of an auto switching valve. In the positive mode of APCI-MS, lycopene, alpha-carotene and beta-carotene were monitored at m/z 537 and I.S. was monitored at m/z 411. This method was linear for all analytes in the range of 15-150 ng for lycopene, 7-70 ng for alpha-carotene and 25-50 ng for beta-carotene. The detection limit of LC-APCI-MS-SIM for carotenoids was about 3 ng per 1 ml of serum (S/N = 3). The repeatabilities, expressed as C.V.s, were 10%, 8.4% and 5.3% for lycopene, alpha-carotene and beta-carotene, respectively. The intermediate precisions, expressed as C.V.s, were 11.2%, 8.8% and 6.5% for lycopene, alpha-carotene and beta-carotene, respectively.

Atmospheric Pressure↗
PubMed1998

Gel Formation from Industrial Milk Whey Proteins under Hydrostatic Pressure: Effect of Hydrostatic Pressure and Protein Concentration.

The effects of high hydrostatic pressure and protein concentration on the denaturation and gelation of whey protein were investigated. Industrial whey protein isolate (WPI) and whey protein concentrate (WPC) solutions (pH 6.8) at various concentrations were pressurized for 10 min at 30 degrees C under 200-1000 MPa. With the WPI solution, the concentration for affecting the turbidity was 1% and was 6% for the viscosity at 400 MPa, while for inducing gelation, it was 10% at 600 MPa. With the WPC solution, the viscosity changed at a concentration >12%, and gel formation began at >18% at 400 MPa. The hardness and breaking stress of pressure-induced WPI gels increased with increasing concentration of WPI (12-18%) and hydrostatic pressure, the ratings for the 20% WPC gels being one-third those of the 20% WPI gels. The solubility of proteins from the pressure-induced WPI gels decreased with increasing pressure, while that of WPC gel induced at >600 MPa remained constant at approximately 50%. The microstructure of the WPI gels had a porous network form, whereas the WPC gels were irregular particulates. beta-Lactoglobulin, alpha-lactalbumin, and serum albumin preferentially participated in pressure-induced aggregation and gelation through S-S bonding.

Journal Article↗
PubMed1998

Inhibition of intestinal microflora beta-glucuronidase modifies the distribution of the active metabolite of the antitumor agent, irinotecan hydrochloride (CPT-11) in rats.

PURPOSE: SN-38, a metabolite of irinotecan hydrochloride (CPT-11), is considered to play a key role in the development of diarrhea as well as in the antitumor activity of CPT-11. We have previously found that the inhibition of beta-glucuronidase, which hydrolyzes detoxified SN-38 (SN-38 glucuronide) to reform SN-38, in the lumen by eliminating the intestinal microflora with antibiotics, markedly ameliorates the intestinal toxicity of CPT-11 in rats. In this study we compared the disposition of CPT-11 and its metabolites in rats treated with and without antibiotics. METHODS: Rats were given drinking water containing 1 mg/ml penicillin and 2 mg/ml streptomycin from 5 days before the administration of CPT-11 (60 mg/kg i.v.) and throughout the experiment. CPT-11, SN-38 glucuronide and SN-38 concentrations in the blood, intestinal tissues and intestinal luminal contents were determined by HPLC. RESULTS: Antibiotics had little or no effect on the pharmacokinetics of CPT-11, SN-38 glucuronide or SN-38 in the blood, or in the tissues or contents of the small intestine, which has less beta-glucuronidase activity in its luminal contents. In contrast, antibiotics markedly reduced the AUC1-24 h of SN-38 (by about 85%) in the large intestine tissue without changing that of CPT-11, and this was accompanied by a complete inhibition of the deconjugation of SN-38 glucuronide in the luminal contents. CONCLUSIONS: These results suggest that SN-38, which results from the hydrolysis of SN-38 glucuronide by beta-glucuronidase in the intestinal microflora, contributes considerably to the distribution of SN-38 in the large intestine tissue, and that inhibition of the beta-glucuronidase activity by antibiotics results in decreased accumulation of SN-38 in the large intestine.

Administration, Oral↗