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Soichi Maruyama

Publications and source records attributed to Soichi Maruyama.

At least 19 recordsLinked to original sources
PubMed2006

Serological survey of Ehrlichia and Anaplasma infection of feral raccoons (Procyon lotor) in Kanagawa Prefecture, Japan.

Numbers of feral raccoon; the possible reservoir animal of Ehrlichia and Anaplasma, are increasing in Japan. Thus serological methods were utilized to examine Ehrlichia and Anaplasma infection in raccoons from Kanagawa Prefecture, Japan. By using an indirect immunofluorescence assay, among 187 feral raccoons examined, 1 (0.5%) serologically reacted with Ehrlichia canis, 3 (1.6%) with Ehrlichia chaffeensis and 1 (0.5%) with Anaplasma phagocytophilum with the titers of 1:40 or more. Although screening PCR for Ehrlichia and Anaplasma species failed to detect the presence of ehrlichial DNA in serum samples, results of the serological tests suggested that the feral raccoons might be infected with some species of Ehrlichia and Anaplasma.

Anaplasma↗
PubMed2006

Seroprevalence of Toxoplasma gondii antibodies in stray cats and dogs in the Bangkok metropolitan area, Thailand.

Cats and dogs are the most popular pet animals worldwide. Cats are the natural reservoir of Toxoplasma gondii and excrete the resistant oocyst to environments. On the other hands, dogs play a role in the mechanical transmission of the parasite. Stray cats and dogs in the Bangkok metropolitan area are becoming a public concern because there is a considerable increase in their number annually. These facts indicate the risk of mechanically spreading zoonoses including toxoplasmosis to humans since human acquire the infection from infected mammals, either directly or indirectly. In the present study, the presence of T. gondii antibodies was examined in 592 cats and 427 dogs from October 2001 to September 2002 by using a latex agglutination test. T. gondii antibodies were detected in 65 (11.0%) of the 592 cats and 40 (9.4%) of the 427 dogs. The antibody titers in the positive animals ranged from 1:64 to 1:2048. Seroprevalence was significantly higher in female cats than in male cats. The present study suggested that T. gondii was widespread in the stray animals in the Bangkok metropolitan area; therefore, it is essential to control the number of stray cats and dogs in order to reduce the transmission of toxoplasmosis to animals and humans.

Animals↗
PubMed2006

Detection of DNA closely related to 'Candidatus Rickettsia principis' in Haemaphysalis danieli recovered from cattle in Xinjiang Uygur Autonomous Region Area, China.

Tick DNA samples from cattle in Xinjiang Uygur Autonomous Region Area, China, were examined for Rickettsia infection by citrate synthase gene-based PCR and sequencing. Four positive samples were detected from Haemaphysalis danieli and high levels of similarity were found with recently detected 'Candidatus Rickettsia principis.'

Animals↗
PubMed2006

Characterization of Th1 activation by Bartonella henselae stimulation in BALB/c mice: Inhibitory activities of interleukin-10 for the production of interferon-gamma in spleen cells.

This study was conducted to analyze cytokine production mechanisms in mice after Bartonella henselae stimulation. BALB/c mice were inoculated intraperitoneally with 3 x 10(6) colony forming units of B. henselae (Houston-1 strain) twice at 10-day interval. Spleen cells were harvested from the mice and stimulated with the organisms. Following the stimulation, interferon-gamma (IFN-gamma) and interleukin-4 (IL-4), IL-10, IL-12 and tumor necrosis factor-alpha (TNF-alpha) were measured in the culture supernatants of the spleen cells by ELISA. The spleen cells specifically secreted IFN-gamma, but not IL-4, indicating that T helper 1 (Th1) cells were activated following B. henselae stimulation. In addition, IL-10 and TNF-alpha productions were also detected in the culture supernatants of spleen cells. Neutralization of IL-10 in the culture supernatants significantly enhanced the production of IFN-gamma from the spleen cells stimulated with B. henselae. These results indicate that B. henselae predominantly stimulated Th1 cells and resulted in secreting IFN-gamma, however the production was partially inhibited by IL-10, which was produced simultaneously.

Angiomatosis, Bacillary↗
PubMed2006

Cat-scratch disease in veterinary-associated populations and in its cat reservoir in Taiwan.

In Taiwan, the first human case of cat-scratch disease (CSD) was diagnosed by a serologic test in 1998. Since then, no studies have been conducted to understand the epidemiology of the infection in Taiwan. Therefore, this study is the first epidemiologic survey of CSD in cats and humans in this country. Using veterinary-associated individuals as the study population, it was identified that 1.7% of them were seropositive for B. henselae, and residence was the only factor associated with seropositivity. Bartonella species were successfully isolated from 25 (19.1%) of the 131 cats tested. Only B. henselae and B. clarridgeiae were obtained from bacteremic cats. Furthermore, 9.2% of 131 cats were dually-infected with genotypes I and II of B. henselae. It is the highest prevalence of co-infection that has ever been reported worldwide. In cats, the seroprevalence was 23.7% by indirect immunofluorescence antibody assay with B. henselae Houston-1 (type I) as the antigen. When 12 bacteremic but seronegative cats were re-tested by IFA slides coated with B. henselae U-4 antigen (type II), 9 cats were identified to be seropositive. Our study further suggested that using only direct PCR of 16S-23S rRNA intergenic region or the combination of the PCR method and indirect immuno-fluorescence test will be useful to diagnose Bartonella-free cats.

Adult↗
PubMed2006

Seroprevalence of Toxoplasma gondii in captive felids in Thailand.

The prevalence of antibodies against Toxoplasma gondii was investigated by commercial latex agglutination test kit (Toxocheck-MT 'Eiken') in captive felids maintained at zoos and a wildlife breeding center in different geographic regions of Thailand. Sera from a total of 136 captive felids of 12 species was obtained between 2002 and 2004. The overall seroprevalence of T. gondii was found in 21 of 136 (15.4%) felids. The titers varied from 1:64 (eight samples) to 1:8192 (one sample). The seroprevalence in different geographic regions were from 0% in the northern area to 23% in the southern area. This study suggested a widespread exposure of captive felids to T. gondii in Thailand and this is the first report of serologic analysis for T. gondii in captive felids in Southeast Asia.

Animals↗
PubMed2006

Predominant T helper 2 immune responses against Bartonella henselae in naturally infected cats.

This study was conducted to explicate the mechanism of long-term bacteremia in Bartonella henselae-infected cats by the examining host immune responses. Blood samples were collected from three naturally infected cats and the IgG antibody titers and the cytokine responses in peripheral blood mononuclear cells (PBMC) were examined by quantitative reverse transcriptase-polymerase chain reactions (RT-PCR). Relapsing bacteremia was found in two of the three cats during the examination period. The quantitative RT-PCR analyses demonstrated that increases of the mRNA expressions in interleukin-4 (IL-4) but not in gamma-interferon (IFN-gamma) were observed in PBMC from these infected cats after the bacteremia had peaked, showing that the T helper 2 (Th2) responses were specifically induced in the cats. Furthermore, the specific antibody titer increased, resulting in a decrease in the number of B. henselae to undetectable levels in these cats. However, the number of bacteria increased again in two of these cats at 90 and 45 days after the previous bacteremia, respectively. These results suggest that B. henselae predominantly induced IL-4 production from PBMC and resulted in stimulation of the humoral immune responses, including the secretion of specific antibodies in the cats. Furthermore, the specific antibody may play a role in eliminating the bacteria from cats partially but not completely, because relapsing bacteremia was found in these two cats.

Animals↗
PubMed2006

Multispacer typing to study the genotypic distribution of Bartonella henselae populations.

Bartonella henselae, a worldwide fastidious bacterium, has a feline reservoir and is pathogenic for humans. However, the relationship between human and cat isolates of B. henselae, as well as its population dynamics and geographic heterogeneity, is not fully understood, in part because of the absence of appropriate typing methods. Multilocus sequence typing (MLST), the most discriminatory genotyping method for B. henselae, identified seven genotypes and suggested that human isolates arose from a limited number of cat isolates. Herein, we estimated the discriminatory power of multispacer typing (MST) by studying 126 B. henselae cat isolates from various areas of Europe, Asia, and the United States. We identified the nine most variable intergenic spacers conserved by both B. henselae and Bartonella quintana genomes. By comparing the sequences obtained from these nine spacers for each studied isolate, we identified 39 MST genotypes. The distribution of isolates into MST genotypes matched their phylogenetic organization into four clusters. MST showed that European and Asian isolates were different, in contrast with American isolates, but failed to identify pandemic strains. Our study demonstrated that MST is a powerful method for genotyping B. henselae at the strain level and may serve in studying the population dynamics of this bacterium and understanding the relationships between cat and human isolates. Finally, we provide a free-access MST-Rick online software program (http://ifr48.timone.univ-mrs.fr/MST_BHenselae/mst) that investigators may use to compare their own MST sequences to our database.

Animals↗
PubMed2006

Detection of Hepatozoon canis in stray dogs and cats in Bangkok, Thailand.

A rapidly increasing stray animal population in Bangkok has caused concern regarding transmission of vector-borne and zoonotic diseases. The purpose of this study was to determine if stray animals in Bangkok are a potential reservoir of Hepatozoon, a genus of tick-borne parasites that has received little attention in Thailand. Blood samples were collected from stray companion animals near monasteries in 42 Bangkok metropolitan districts. Both dogs and cats were sampled from 26 districts, dogs alone from 4 districts and cats alone from 12 districts. Samples were collected from a total of 308 dogs and 300 cats. Light microscopy and an 18 S rRNA gene-based PCR assay were used to test these samples for evidence of Hepatozoon infection. Gamonts were observed in blood smears for 2.6% of dogs and 0.7% of cats by microscopy. The PCR assay detected Hepatozoon in buffy coats from 11.4% of dogs and 32.3% of cats tested. The prevalence of infection was the same between male and female dogs or cats, and PCR-positive dogs and cats were found in 36.6% and 36.8% of the districts surveyed, respectively. There was an association between the percentages of PCR-positive dogs and cats in districts where both host species were sampled. Sequences of representative amplicons were closest to those reported for H. canis. These results represent the first molecular confirmation that H. canis is indigenous to Thailand. The unexpectedly high prevalence of Hepatozoon among stray cats indicates that their role in the epizootiology of hepatozoonosis should be investigated.

Animals↗
PubMed2006

Seroepidemiological evidence for the possible presence of Babesia (Theileria) equi and Babesia caballi infections in donkeys in western Xinjiang, China.

The prevalence of Babesia (Theileria) equi and B. caballi infections in donkeys in western Xinjiang China was investigated. In total, 93 serum samples were randomly taken from donkeys in the Kashi and Ili areas, and examined for B. equi and B. caballi infections by enzyme-linked immunosorbent assays using recombinant antigens. Of the 93 samples, 9 (9.6%) and 36 (38.7%) samples were positive for B. equi infection and B. caballi infection, respectively. In addition, 2 (2.2%) samples were positive for both B. equi and B. caballi infections. These results indicate that equine babesiosis might be extensively prevalent in donkeys in western Xinjiang.

Animals↗
PubMed2006

Bartonella spp. in pets and effect on human health.

Among the many mammals infected with Bartonella spp., pets represent a large reservoir for human infection because most Bartonella spp. infecting them are zoonotic. Cats are the main reservoir for Bartonella henselae, B. clarridgeiae, and B. koehlerae. Dogs can be infected with B. vinsonii subsp. berkhoffii, B. henselae, B. clarridgeiae, B. washoensis, B. elizabethae, and B. quintana. The role of dogs as an important reservoir of Bartonella spp. is less clear than for cats because domestic dogs are more likely to be accidental hosts, at least in nontropical regions. Nevertheless, dogs are excellent sentinels for human infections because a similar disease spectrum develops in dogs. Transmission of B. henselae by cat fleas is better understood, although new potential vectors (ticks and biting flies) have been identified. We review current knowledge on the etiologic agents, clinical features, and epidemiologic characteristics of these emerging zoonoses.

Animals↗
PubMed2005

Serological evidence of infection of Anaplasma and Ehrlichia in domestic animals in Xinjiang Uygur Autonomous Region area, China.

Serological methods were utilized to detect Anaplasma and Ehrlichia infection in domestic animals in Xinjiang Uygur Autonomous Region, China. By using an indirect immunofluorescence assay (IFA), antibodies that reacted with Anaplasmaphagocytophilum and Ehrlichiachaffeensis were detected mainly in ruminants kept on pastureland in Altai, Ili and Kashgar area. Antibody titers up to 1:320 were recorded. These results indicate that ruminants kept in these areas may be infected with some species of Anaplasma and Ehrlichia.

Anaplasma phagocytophilum↗
PubMed2005

The marked increase of Listeria monocytogenes isolation from contents of swine cecum.

The actual prevalence of Listeria monocytogenes from contents of swine cecum was investigated. The efficiency of Listeria enrichment broth (LEB) for isolation was examined by the recovery of artificially inoculated L. monocytogenes in contents of swine cecum. The numbers of organisms did not increase after 48 h incubation, but increased when the rapid decrease in pH of the LEB was adjusted. Between 1991 and 1993, 250 contents of swine cecum were examined for the prevalence of L. monocytogenes using LEB enrichment, either with or without pH adjustment. L. monocytogenes was isolated from 74 samples in 1993 with pH adjustment, however, no organisms were isolated in 1991 and 1992. It was suggested that the marked rise of the L. monocytogenes isolation was due to the spread of the organism among swine. Furthermore, 67 out of the 74 isolates were identified as 1/2c by serotyping. The serovar 1/2c strains showed genetic diversity by random amplified polymorphic DNA.

Animals↗
PubMed2005

Seroprevalence of Toxoplasma gondii infection in domestic goats in Satun Province, Thailand.

Goats are important domestic animals in the south of Thailand due to the minimal cost of rearing and maintaining them, and their production of both meat and milk. Toxoplasmosis is one of the most threatening parasitic zoonoses and the causative agent Toxoplasma gondii uses a wide range of warm-blooded intermediate hosts including the goat. The objective of this study was to assess the seroprevalence of antibodies to T. gondii in goats of Satun Province in Thailand. A total of 631 goat sera were examined for antibodies against toxoplasmosis with commercial latex agglutination test kits (Toxocheck-MT 'Eiken'). Of these, 176 (27.9%) were found to be positive to T. gondii; antibody titers ranged from 1:64 to 1:4096 (1:64 cut-off). Female goats were 1.73 times more likely than male to be seropositive (odds ratio [OR]=1.73; 95% confidential interval [CI]=1.11, 2.73). Dairy goats were more likely to be seropositive than meat goats (OR=1.36; 95% CI=0.84, 2.20). Goats were infected with T. gondii with acquisition of age because older goats were more likely to be seropositive than young goats under 1-year-old (for 1-2 years, OR=19.6; 95% CI=0.92, 4.15, for >2 years, OR=2.70; 95% CI=1.26, 5.80). The high seroprevalence of T. gondii antibodies found in the present study suggested widespread exposure of goats in Satun Province to T. gondii.

Age Factors↗
PubMed2005

Influence of bacteriocin-like substance, generation times, and genetic profiles of Listeria innocua on the isolation of Listeria monocytogenes.

Inhibition of isolation of Listeria monocytogenes by bacteriocin-like substance (BLS)-producing Listeria innocua after enrichment culture was investigated. When 26 L. monocytogenes strains were examined in combination with eight L. innocua strains using the spot on lawn method, 52/208 (25.0%) combinations showed the growth inhibition of L. monocytogenes. When two Listeria species were cultured simultaneously in selective enrichment broth, inhibition of isolation of L. monocytogenes was observed in 12/52 of the combinations at 24h (23.1%), in 24/52 at 48h (46.2%) and in 30/52 (57.7%) after 7 days of incubation. The randomly amplified polymorphic DNA profiles showed no interstrain similarities between either strains of the BLS-producing L. innocua or the BLS-sensitive L. monocytogenes strains. Therefore inhibition by BLS-producing L. innocua of isolation of L. monocytogenes after enrichment culture is unlikely to be dependent upon a particular genetic profile.

Bacteriocins↗
PubMed2004

Prevalence of Arcobacter species in retail meats and antimicrobial susceptibility of the isolates in Japan.

A survey was conducted to examine the prevalence of Arcobacter species among meat samples and to investigate the antimicrobial susceptibility of the isolates in Japan. In 1998 and 1999, samples of beef (n=90), pork (n=100) and chicken meat (n=100) were purchased from seven retail shops. Arcobacter species were isolated from 2.2%, 7.0% and 23.0% of beef, pork and chicken meat samples, respectively. The rate of isolations in chicken meats was shown to be significantly higher than those of beef and pork. Species-specific polymerase chain reaction (PCR) demonstrated that the most dominant Arcobacter species was Arcobacter butzleri among the isolates examined. Multiple contaminations with different Arcobacter species were observed in 5% of the chicken samples. Almost all the strains tested showed resistance to vancomycin (100%) and methicillin (97.5%). Strains resistant to cephalothin, sulfamethoxazole-trimethoprim, nalidixic acid and chloramphenicol were detected at the rate of 81.1%, 67.2%, 53.5% and 24.6%, respectively. All Arcobacter strains examined were susceptible to ampicillin, tetracycline, streptomycin and kanamycin.

Animals↗
PubMed2004

Genetic diversity of the dnaJ gene in the Mycobacterium avium complex.

The Mycobacterium avium complex (MAC) is associated with various diseases in humans as a zoonosis. The dnaJ gene was partially sequenced in Schaefer's 28 reference strains of MAC, 14 human MAC isolates and 22 veterinary isolates. From substitutions affecting 21-32 nucleotides, all strains could be classified into 14 groups. Most nucleotide substitutions did not alter amino acid sequences. Approximately 8 % genetic diversity was seen in these strains, which divided into two clusters: cluster I (0.8 % genetic diversity), comprising the reference strain serotypes 1-6, 8-11 and 21 and all isolates; and cluster II (7 % genetic diversity), comprising the remaining reference strains. Analysis of the dnaJ gene in MAC may be useful in epidemiological studies.

Animals↗