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Hideto Fukushi

Publications and source records attributed to Hideto Fukushi.

33 records · Page 2Linked to original sources
PubMed2004

In vitro susceptibility to tetracycline and fluoroquinolones of Japanese isolates of Coxiella burnetii.

Coxiella burnetii is the agent of the worldwide zoonosis, Q fever. The in vitro susceptibility to tetracycline and fluoroquinolones of Japanese isolates of C. burnetii was evaluated for the first time. The MICs against Japanese isolates were almost the same as the MICs against the foreign reference isolates. The results suggest that the common antibiotics therapy for Q fever used in other countries is also effective for Japanese Q fever patients.

Anti-Bacterial Agents↗
PubMed2004

Growth and virulence alterations of equine herpesvirus 1 by insertion of a green fluorescent protein gene in the intergenic region between ORFs 62 and 63.

Nucleotide sequences of the intergenic region between ORF 62 and ORF 63 of equine herpesvirus 1 (EHV-1) isolates were analyzed. The sequences of this region consisted of variable and conserved domains among EHV-1 isolates. An EHV-1 mutant, Ab4-GFP, was constructed by inserting a green fluorescent protein (GFP) expression cassette flanked by lox P at both ends into the intergenic region between ORF 62 and ORF 63. Another mutant, Ab4-loxP, which contains one lox P site, was constructed by excision of the GFP cassette from the Ab4-GFP virus genome by cre enzyme. The recombinant Ab4-GFP formed smaller plaques than the wild type in MDBK cells. Virus production also decreased for Ab4-GFP in multistep growth analyses. Virulence of Ab4-GFP in both mice and hamsters was weaker than that of the wild type. Ab4-loxP exhibited properties similar to those of the wild type. These results suggest that the intergenic region between ORF 62 and ORF 63 plays various roles in the virus growth.

Animals↗
PubMed2004

Comparison of Japanese isolates of Coxiella burnetii by PCR-RFLP and sequence analysis.

The genetic variation of Japanese isolates of Coxiella burnetii, the agent of Q fever, was found for the first time. Forty-nine out of 72 isolates had the chronic pattern of the isocitrate hydrogenase gene. Sequence analysis revealed that the isolates have a specific nucleotide sequence. The putative amino acid sequence was the same as that of chronic reference strains. These results suggest the variation of C. burnetii isolates in Japan.

Amino Acid Sequence↗
PubMed2004

Use of monoclonal antibodies for analyses of Coxiella burnetii major antigens.

Monoclonal antibodies (MAbs) to major antigens of Coxiella burnetii were produced. Some of the MAbs to a 62-kDa protein antigen, peptidoglycan protein complex and lipopolysaccharide (LPS) O-chains reacted with other bacteria whereas none of the MAbs to outer membrane proteins and LPS outer-core did. The LPS outer-core and OMPs may be useful antigens for specifically detecting antibodies to C. burnetii.

Antibodies, Bacterial↗
PubMed2004

[Method of estimating 10 MV X-ray irregular field dose using the collimator scatter factor (Sc) and phantom scatter factor (Sp)].

It has been found that in general 10 MV X-ray dose calculation can be made accurately for multi-leaf collimator irregular fields by using the total scatter factor (S(cp)), collimator scatter factor (S(c)), and phantom scatter factor (S(p)) proposed by Khan et al. With respect to the collimator scatter factor (S(c)), we used the field-mapping method of Kim et al. to obtain equivalent square fields of irregular fields (the collimator reverse effect can be accurately dissolved using the field-mapping method). Even for extremely small multi-leaf fields compared with the main collimator opening, X-ray output calculations could be made accurately by introducing the small segment correction (SSC) factor. With respect to the phantom scatter factor (S(p)), highly accurate calculations could be made for irregular field irradiation by applying an F(MLC) (MLC radiation leakage) factor to the equivalent square field (in cases in which the ratio of the multi-leaf equivalent square field side to the main collimator equivalent square field side is less than 0.6). However, it has been found that highly accurate dose calculations can, in general, be performed when the main collimator is limited just at the opening determined by the multi-leaf collimator field.

Phantoms, Imaging↗
PubMed2004

[Method for estimating 4 MV X-ray irregular field dose using the collimator scatter factor (Sc) and phantom scatter factor (Sp)].

Calculation of in-air or in-water dose for 4 MV X-ray irregular fields could be accurately performed using the collimator scatter factor (S(c)) and phantom scatter factor (S(p)) concepts. It has been revealed that the equivalent square field for a multi-leaf collimator (MLC) irregular field can be evaluated accurately by using the S(p)-Clarkson or S(c)-Clarkson integration method; however, the S(c)-Clarkson integration method is more straightforward because the S(c) factor expresses the in-air X-ray output factor. It has been found that when the MLC field is relatively much smaller than the main collimator field, the Sc factor can be accurately evaluated by introducing the small segment correction (SSC) factor (except for the case in which the MLC field is less than 1 x 1 cm(2)). It has also been found that both the S(p) factor and the tissue-phantom ratio (TPR) can be precisely evaluated by introducing the F(MLC) factor in cases in which the ratio of the MLC equivalent square field side to the main collimator equivalent square field side is less than about 0.7.

Phantoms, Imaging↗
PubMed2003

Epidemiological survey on the route of Coxiella burnetii infection in an animal hospital.

The source of Q fever infection, was investigated by serological and polymerase chain reaction (PCR) analysis of specimens from humans and pets in an animal hospital. Two animal health technicians showed a positive serological reaction against Coxiella burnetiiat the start. One of the two positive subjects remained PCR-positive for about 1 year and the other converted to PCR-negative, but the IgG antibody titer remained at 1 : 128 after minocycline treatment. Among animals housed in the hospital, two dogs were PCR-positive at the start, and the infection was transmitted to three cats about 5 months later. All these animals became negative for C. burnetii DNA after minocycline treatment. Furthermore, C. burnetii was isolated from the sera of the two humans and two dogs. C. burnetiiisolates from the humans and dogs were analyzed, and it was found that the sequence homology of the com1 region was high, 99.9%, and the QpH1 plasmid was detected. These results suggest that these isolates were the same type, and it was considered that the infection was derived from the dogs, though the time of infection could not be confirmed.

Animals↗
PubMed2003

Diagnostic evaluation of 2', 5'-oligoadenylate synthetase activities and antibodies against Epstein-Barr virus and Coxiella burnetii in patients with chronic fatigue syndrome in Japan.

To investigate the association of viral infections with chronic fatigue syndrome (CFS), we assayed 2', 5'-oligoadenylate synthetase (2-5AS) activities in peripheral blood mononuclear cells from CFS patients in Japan. These patients were diagnosed in two hospitals, H1 and H2, located in different areas of the country. The activities were detected in 19 (86%) and 7 (32%) of each of the 22 patients in H1 and H2, respectively, while they were detected in only four (11%) out of the 38 healthy controls. IFN-alpha was similarly detected in a few CFS patients and healthy controls. We also assayed the antibody titers against Epstein-Barr virus (EBV) and Coxiella burnetii in these patients. The EBV anti-EA-IgG antibodies were detected in two (9%) and seven (32%) of each of the 22 patients in H1 and H2, respectively. Anti-C. burnetii IgG antibodies were detected in six (27%) out of 22 patients in H1 but not in 22 patients in H2, while they were detected in one (11%) of the nine healthy controls. Some CFS patients may be associated with EBV or C. burnetii infection. There were some statistical correlations between the 2-5AS activities and antibody titers of EA-IgG (P < 0.05, Student's t-test) but not to the antibody titers of C. burnetii. The up-regulation of 2-5AS activities suggests immunological dysfunctions with some virus infections in the CFS patients. Our results indicate that 2-5AS activities are useful for a diagnostic marker of CFS and for exploring the complicated pathogenesis of CFS.

2',5'-Oligoadenylate Synthetase↗
PubMed2003

SCID mouse model for lethal Q fever.

Q fever, a worldwide zoonosis caused by Coxiella burnetii, has many manifestations in humans. Endocarditis is the most serious complication of Q fever. Animal models are limited to acute pulmonary or hepatic disease and reproductive disorders. An appropriate experimental animal model for Q fever endocarditis does not yet exist. In this study, severe combined immunodeficient (SCID) mice infected with C. burnetii showed persistent clinical symptoms and died, whereas immunocompetent mice similarly infected became asymptomatic and survived. The SCID mice examined in this study had severe chronic lesions in their primary organs: the heart, lung, spleen, liver, and kidney. The heart lesions of the SCID mice were similar to those in humans with chronic Q fever endocarditis: they had focal calcification and expanded macrophages containing C. burnetii. The 50% lethal dose of C. burnetii in SCID mice was at least 10(8) times less than that in immunocompetent mice. The SCID mouse is highly susceptible to C. burnetii, and the immunodeficiency of the host enhances the severity of Q fever. This animal model could provide a new tool for the study of chronic Q fever and Q fever in immunodeficient hosts.

Animals↗
PubMed2003

Seroprevalence of Coxiella burnetii infections among cats in different living environments.

The seroprevalence of Coxiella burnetii infection among pet cats in Japan and Korea and stray cats in Japan was investigated by an indirect fluorescent antibody technique and PCR test. Forty-four (14.2%) of 310 pet cats in Japan were seropositive, as were 15 (41.7%) of 36 stray cats in Japan and 10 (8.6%) of 116 pet cats in Korea. The antibody positive rate in stray cats was significantly higher than that in pet cats, but there was no correlation between the rates in Japanese and Korean pet cats. In this study, the prevalence of C. burnetii infection among cats in different living environments was found and it is difficult to deny that stray cats would be one of the important sources of infection for human Q fever.

Animals↗
PubMed2003

[Ehrlichiosis].

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Animals↗
PubMed2002

Phase variation analysis of Coxiella burnetii during serial passage in cell culture by use of monoclonal antibodies.

Antigenic changes in Coxiella burnetii Nine Mile strain phase I during serial passages in cell culture were analyzed with three groups of monoclonal antibodies (MAbs) against lipopolysaccharide. The MAbs of group 1 did not react with organisms that were passaged over five times, and the MAbs of group 2 did not react with organisms that were passaged over eight times. The MAbs of group 3 reacted with organisms passaged up to 15 times but did not react with phase II cells. These results suggest that C. burnetii could be differentiated into four phase states during phase variation.

Animals↗
PubMed2002

An etiological investigation of domestic cats with conjunctivitis and upper respiratory tract disease in Japan.

Chlamydophila felis (C. felis), feline herpesvirus-1 (FHV-1) and feline calicivirus (FCV) were detected in 39 (59.1%), 11 (16.7%) and 14 (21.2%) cats respectively, from 66 domestic cats presented with conjunctivitis and upper respiratory tract disease (URTD) in 9 prefectures of Japan. Dual and multiple infections were found in 7 (10.6%) cats with both C. felis and FHV-1, 10 (15.2%) cats with both C. felis and FCV, and 1 (1.5%) cat with all three agents. C. felis was isolated from 11 (28.2%) of 39 PCR positive cats. Antigenic difference was found in a 96 kDa protein of our isolates and Fe/145 strain isolated in USA. In conclusion, C. felis is the most common agent of feline conjunctivitis and URTD, and the coinfection with C. felis, FHV-1 and FCV are also common in cats in Japan.

Animals↗
PubMed2002

[Comments on evaluation method for equivalent square fields to the collimator scatter factors of rectangular fields].

In the measurement of 4 MV and 10 MV X-ray collimator scatter factors (S(c)), the method of using an acrylic mini-phantom showed no significant differences between cases in which the chamber axis was either parallel or perpendicular to the beam axis. Chamber readings with an aluminum or acrylic build-up cap were not reflected by contaminant electrons when the chamber axis was parallel to the beam axis. On the basis of the data on 4 MV and 10 MV X-ray collimator Sc measured using an acrylic mini-phantom, we examined three methods of obtaining square fields equivalent to rectangular fields, and reached the following conclusions: (1) The A/P method was not accurate because it did not take into account the structure of the radiation head. (2) Regarding the geometrical weight factor (k) used in the field-mapping method, more accurate k values were obtained when using the geometrical places of the flattening filter (or the second source, taken from the concept of extra-focal radiation), the upper and lower collimators, and the chamber, rather than when using the geometrical places of the source, the upper and lower collimators, and the chamber. (3) The most accurate k values could, in general, be obtained when determined on the basis of measured S(c) data.

Phantoms, Imaging↗