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1.
Appl Environ Microbiol ; 84(7)2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29374041

RESUMO

Parasites of the Babesiadivergens Asia lineage, which are closely related to B. divergens in Europe and Babesia sp. strain MO1 in the United States, were recently reported in sika deer (Cervus nippon) in eastern Japan. To identify the tick vector(s) for this parasite, we conducted a field survey in Hokkaido, Japan, where the infection rate in sika deer is the highest in the country. A specific PCR system which detects and discriminates between lineages within B. divergens and between those lineages and Babesia venatorum showed that Ixodes persulcatus (11/822), but not sympatric Ixodes ovatus (0/595) or Haemaphysalis sp. (0/163) ticks, carried B. divergens Asia lineage. Genomic DNA was archived from salivary glands of partially engorged I. persulcatus females and three isolates of B. divergens Asia lineage were newly described. The 18S rRNA gene sequence of the isolates formed the Asia lineage cluster with those previously described in sika deer isolates. One salivary gland also contained parasites of Babesia microti U.S. lineage, which were subsequently isolated in a hamster in vivoB. venatorum (strain Etb5) was also detected in one I. persulcatus tick. The 18S rRNA sequence of Etb5 was 99.7% identical to that of B. venatorum (AY046575) and was phylogenetically positioned in a taxon composed of B. venatorum isolates from Europe, China, and Russia. The geographical distribution of I. persulcatus is consistent with that of B. divergens in sika deer in Japan. These results suggest that I. persulcatus is a principal vector for B. divergens in Japan and Eurasia, where I. persulcatus is predominantly distributed.IMPORTANCE The Babesiadivergens Asia lineage of parasites closely related to B. divergens in Europe and Babesia sp. MO1 in the United States was recently reported in Cervus nippon in eastern Japan. In this study, specific PCR for the Asia lineage identified 11 positives in 822 host-seeking Ixodes persulcatus ticks, a principal vector for many tick-borne disease agents. Gene sequences of three isolates obtained from DNA in salivary glands of female ticks were identical to each other and to those in C. nippon We also demonstrate the coinfection of B. divergens Asia lineage with Babesia microti U.S. lineage in a tick salivary gland and, furthermore, isolated the latter in a hamster. These results suggest that I. persulcatus is the principal vector for B. divergens as well as for B. microti, and both parasites may be occasionally cotransmitted by I. persulcatus This report will be important for public health, since infection may occur through transfusion.


Assuntos
Babesia/fisiologia , Babesiose/transmissão , Cervos , Ixodes/parasitologia , Animais , Babesia/genética , Babesiose/parasitologia , Sequência de Bases , DNA de Protozoário/análise , Interações Hospedeiro-Parasita , Japão , RNA Ribossômico 18S/análise
2.
Transfusion ; 58(5): 1234-1244, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29524239

RESUMO

BACKGROUND: Human babesiosis is caused mainly by Babesia microti and has recently become a public health concern due to an increase in transfusion-transmitted infection. Thus, the development of an antibody detection method with high specificity and sensitivity is a priority. Seroreactivity against B. microti has been reported to be highly specific not only to B. microti lineages but also to sublineages. This study aimed to elucidate the human antibody reactivity against various lineages, including US, Kobe, and Hobetsu, and sublineages (North America and East Asia) in the US lineage. STUDY DESIGN AND METHODS: Twenty samples obtained from individuals infected with B. microti in the United States were tested for the presence of anti-B. microti antibodies using indirect immunofluorescence assay (IFA) and Western blotting (WB) to indicate antigens of each (sub-)lineage. RESULTS: By IFA, 20 samples showed reactivity to the North America sublineage (titer range, 64-4096), 16 to the East Asia sublineage (64-512), 10 to the Kobe (64-128), and five to the Hobetsu (64). Antibody titers to the East Asia sublineage, Kobe, and Hobetsu were significantly lower than those to the North America sublineage (p < 0.01). By WB, in parallel with the IFA results, 18 samples showed strong reactions to the North America sublineage, weak reactions to the East Asia sublineage, and near-zero reactions to the Kobe and Hobetsu. CONCLUSION: Human antibodies induced by B. microti infection are highly specific against B. microti lineages and sublineages with low cross-reactivity. Developing a precise antibody detection method may require specific antigens based on B. microti lineages and sublineages.


Assuntos
Babesia microti/imunologia , Babesiose/diagnóstico , Reações Cruzadas/imunologia , Animais , Anticorpos Antiprotozoários , Antígenos de Protozoários , Humanos , América do Norte , Parasitos/imunologia
3.
Appl Environ Microbiol ; 82(22): 6624-6632, 2016 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-27590815

RESUMO

The U.S. lineage, one of the major clades in the Babesia microti group, is known as a causal agent of human babesiosis mostly in the northeastern and upper midwestern United States. This lineage, however, also is distributed throughout the temperate zone of Eurasia with several reported human cases, although convincing evidence of the identity of the specific vector(s) in this area is lacking. Here, the goal was to demonstrate the presence of infectious parasites directly in salivary glands of Ixodes persulcatus, from which U.S. lineage genetic sequences have been detected in Asia, and to molecularly characterize the isolates. Five PCR-positive specimens were individually inoculated into hamsters, resulting in infections in four; consequently, four strains were newly established. Molecular characterization, including 18S rRNA, ß-tubulin, and CCT7 gene sequences, as well as Western blot analysis and indirect fluorescent antibody assay, revealed that all four strains were identical to each other and to the U.S. lineage strains isolated from rodents captured in Japan. The 18S rRNA gene sequence from the isolates was identical to those from I. persulcatus in Russia and China, but the genetic and antigenic profiles of the Japanese parasites differ from those in the United States and Europe. Together with previous epidemiological and transmission studies, we conclude that I. persulcatus is likely the principal vector for the B. microti U.S. lineage in Japan and presumably in northeastern Eurasia. IMPORTANCE: The major cause of human babesiosis, the tick-borne blood parasite Babesia microti, U.S. lineage, is widely distributed in the temperate Northern Hemisphere. However, the specific tick vector(s) remains unidentified in Eurasia, where there are people with antibodies to the B. microti U.S. lineage and cases of human babesiosis. In this study, the first isolation of B. microti U.S. lineage from Ixodes persulcatus ticks, a principal vector for many tick-borne diseases, is described in Japan. Limited antigenic cross-reaction was found between the Japan and United States isolates. Thus, current serological tests based on U.S. isolates may underestimate B. microti occurrence outside the United States. This study and previous studies indicate that I. persulcatus is part of the B. microti U.S. lineage life cycle in Japan and, presumably, northeastern Eurasia. This report will be important for public health, especially since infection may occur through transfusion, and also to researchers in the field of parasitology.


Assuntos
Vetores Aracnídeos/parasitologia , Babesia microti/isolamento & purificação , Babesiose/parasitologia , Babesiose/transmissão , Ixodes/parasitologia , Animais , Antígenos de Protozoários/genética , Babesia microti/classificação , Babesia microti/genética , Babesiose/epidemiologia , China/epidemiologia , Cricetinae , DNA de Protozoário/genética , Feminino , Humanos , Ixodes/anatomia & histologia , Japão/epidemiologia , Meio-Oeste dos Estados Unidos/epidemiologia , Reação em Cadeia da Polimerase , RNA Ribossômico 18S/genética , Roedores/parasitologia , Federação Russa/epidemiologia , Glândulas Salivares/parasitologia , Tubulina (Proteína)/genética
4.
Asia Pac J Oncol Nurs ; 10(4): 100198, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36949819

RESUMO

Objective: The aim of this study was to quantitatively evaluate the efficacy of a self-monitoring intervention for the management of persistent chemotherapy-induced peripheral neuropathy (CIPN). Methods: A randomized controlled clinical trial was conducted on 65 outpatients receiving taxane or platinum-based anticancer drugs. Participants were assigned to the control group (CG; n â€‹= â€‹32) or the self-monitoring group (SMG; n â€‹= â€‹33) and followed for 6 weeks. Non-interveners were blinded. Participants in the intervention group self-monitored and recorded. The researchers provided feedback on the recorded symptoms and coping strategies once every 3 weeks. The efficacy of the 6-week self-monitoring intervention was assessed, using various measures, at baseline (T0), 3 weeks (T1), and 6 weeks (T2). Scores of CIPN, Functional Assessment of Cancer Therapy/Gynecologic Oncology Group-Neurotoxicity, Distress and Impact Thermometer, Self-Efficacy Scale for Advanced Cancer, and Functional Assessment of Cancer Therapy-General of both groups were compared. Safety behavior in daily life was also compared. The study was conducted from August 9, 2017 to March 30, 2020 in outpatient clinics at three hospitals. Analysis was conducted using the t-test, Mann-Whitney U test, χ2 test, and two-way repeated-measures analysis of variance (two-way RMANOVA). Results: No significant differences were noted between the two groups in the CIPN score, the Distress and Impact Thermometer score, and in safety behavior in daily life. The mean Self-Efficacy Scale for Advanced Cancer score at T1 differed between the two groups (CG mean â€‹± â€‹SD: 358.44 â€‹± â€‹109.90; SMG mean â€‹± â€‹SD: 421.21 â€‹± â€‹85.54), which was significantly higher in the SMG (P â€‹= â€‹0.012). Two-way RMANOVA revealed an interaction between the CG and SMG (F â€‹= â€‹5.689, P â€‹= â€‹0.004). Quality of life scores were higher in the SMG than in the CG at T0, T1, and T2. Two-way RMANOVA analysis showed an effect of the intervention (F â€‹= â€‹7.914, P â€‹= â€‹0.007). Conclusions: The self-monitoring intervention maintained the participants' quality of life. This finding suggests its effectiveness in patients with peripheral neuropathy.

5.
Appl Environ Microbiol ; 78(9): 3424-30, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22389378

RESUMO

The species Babesia microti, commonly found in rodents, demonstrates a high degree of genetic diversity. Three lineages, U.S., Kobe, and Hobetsu, are known to have zoonotic potential, but their tick vector(s) in Japan remains to be elucidated. We conducted a field investigation at Nemuro on Hokkaido Island and at Sumoto on Awaji Island, where up to two of the three lineages occur with similar frequencies in reservoirs. By flagging vegetation at these spots and surrounding areas, 4,010 ticks, comprising six species, were collected. A nested PCR that detects the 18S rRNA gene of Babesia species revealed that Ixodes ovatus and I. persulcatus alone were positive. Lineage-specific PCR for rRNA-positive samples demonstrated that I. ovatus and I. persulcatus carried, respectively, the Hobetsu and U.S. parasites. No Kobe-specific DNA was detected. Infected I. ovatus ticks were found at multiple sites, including Nemuro and Sumoto, with minimum infection rates (MIR) of ∼12.3%. However, all I. persulcatus ticks collected within the same regions, a total of 535, were negative for the Hobetsu lineage, indicating that I. ovatus, but not I. persulcatus, was the vector for the lineage. At Nemuro, U.S. lineage was detected in 2 of 139 adult I. persulcatus ticks (MIR, 1.4%), for the first time, while 48 of I. ovatus ticks were negative for that lineage. Laboratory experiments confirmed the transmission of Hobetsu and U.S. parasites to hamsters via I. ovatus and I. persulcatus, respectively. Differences in vector capacity shown by MIRs at Nemuro, where the two species were equally likely to acquire either lineage of parasite, may explain the difference in distribution of Hobetsu throughout Japan and U.S. taxa in Nemuro. These findings are of importance in the assessment of the regional risk for babesiosis in humans.


Assuntos
Babesia microti/classificação , Babesia microti/isolamento & purificação , Ixodes/parasitologia , Animais , Babesia microti/genética , Babesiose/transmissão , Cricetinae , DNA de Protozoário/genética , DNA Ribossômico/genética , Modelos Animais de Doenças , Japão , Reação em Cadeia da Polimerase , RNA Ribossômico 18S/genética
6.
Arch Virol ; 157(11): 2179-87, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22828778

RESUMO

We developed serological tools for the detection of hantavirus-specific antibodies and hantavirus antigens in shrews. The work was focussed to generate Thottapalayam virus (TPMV)-specific monoclonal antibodies (mAbs) and anti-shrew immunoglobulin G (IgG) antibodies. The mAbs against TPMV nucleocapsid (N) protein were produced after immunization of BALB/c mice with recombinant TPMV N proteins expressed in Escherichia coli, baculovirus and Saccharomyces cerevisiae-mediated expression systems. In total, six TPMV N-protein-specific mAbs were generated that showed a characteristic fluorescent pattern in indirect immunofluorescence assay (IFA) using TPMV-infected Vero cells. Out of the six mAbs tested, five showed no cross-reaction to rodent-associated hantaviruses (Hantaan, Seoul, Puumala, Tula, Dobrava-Belgrade and Sin Nombre viruses) in IFA and enzyme-linked immunosorbent assay (ELISA), although one mAb reacted to Sin Nombre virus in IFA. None of the mAbs cross-reacted with an amino-terminal segment of the shrew-borne Asama virus N protein. Anti-shrew-IgG sera were prepared after immunization of rabbits and BALB/c-mice with protein-G-purified shrew IgG. TPMV-N-protein-specific sera were raised by immunisation of Asian house shrews (Suncus murinus) with purified yeast-expressed TPMV N protein. Using these tools, an indirect ELISA was developed to detect TPMV-N-protein-specific antibodies in the sera of shrews. Using an established serological assay, high TPMV N protein specific antibody titres were measured in the sera of TPMV-N-protein-immunized and experimentally TPMV-infected shrews, whereas no cross-reactivity to other hantavirus N proteins was found. Therefore, the generated mAbs and the established ELISA system represent useful serological tools to detect TPMV, TPMV-related virus antigens or hantavirus-specific antibodies in hantavirus-infected shrews.


Assuntos
Anticorpos Monoclonais , Anticorpos Antivirais , Infecções por Hantavirus/veterinária , Orthohantavírus/isolamento & purificação , Musaranhos/virologia , Animais , Anticorpos Monoclonais/isolamento & purificação , Anticorpos Antivirais/isolamento & purificação , Antígenos Virais/imunologia , Reações Cruzadas , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Orthohantavírus/classificação , Infecções por Hantavirus/diagnóstico , Camundongos , Camundongos Endogâmicos BALB C , Proteínas do Nucleocapsídeo/imunologia , Proteínas Recombinantes/imunologia , Sensibilidade e Especificidade , Testes Sorológicos/métodos , Medicina Veterinária/métodos , Virologia/métodos
7.
J Vet Med Sci ; 84(3): 338-341, 2022 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-35110460

RESUMO

The present study examined the presence of Babesia parasites in 104 domestic dogs in Nigeria. Sequentially, Babesia parasites infecting domestic dogs underwent genetic and phylogenetic analyses. The results of nested PCR based on the Piroplasmida 18S rRNA gene illustrated that 13.5% (14/104) of the samples were positive. The obtained positive samples determined the nucleotide sequences of the 18S rRNA genes. In the genetic and phylogenetic analyses, four of five nucleotide sequences were similar to Babesia canis rossi, and one sample exhibited a close similarity to a Babesia sp. isolated from a raccoon in Hokkaido, Japan. The present study revealed the widespread presence of B. canis rossi among domestic dogs in Nigeria.


Assuntos
Babesia , Babesiose , Doenças do Cão , Parasitos , Animais , Babesiose/epidemiologia , Babesiose/parasitologia , Doenças do Cão/epidemiologia , Doenças do Cão/parasitologia , Cães , Nigéria/epidemiologia , Parasitos/genética , Filogenia , RNA Ribossômico 18S/genética
8.
Jpn J Infect Dis ; 73(1): 68-71, 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31564691

RESUMO

Babesia divergens is the major causal agent of zoonotic human babesiosis across Europe. Previously, we reported the detection of a B. divergens Asia lineage in wild sika deer (Cervus nippon) in Japan which was genetically closely related to the European B. divergens. To further elucidate its etiology, we conducted a large epidemiological survey by combining lineage-specific PCR system and blood direct PCR. The infection rate of the Asia lineage was 6.6% (116/1,747) throughout Japan, where Hokkaido (45%), Nagano (17%), Iwate (12%), Gunma (11%), and Yamanashi (11%) were highly enzootic (> 10%) among the 30 prefectures examined. European B. divergens was not detected. A geographical information system (GIS) map revealed dense populations of PCR-positive deer in the mountains including the Japanese Alps in eastern Honshu, and Hokkaido. These areas markedly overlapped with the major habitats of Ixodes persulcatus, a principal tick vector responsible for the transmission of the Asia lineage. Other areas in southern Japan including Miyazaki, Kagoshima, and Shimane Prefectures, where positive sika deer were sporadically detected, may be habitats for other tick species involved in the enzootic cycle as I. persulcatus were scarce. The rise in human babesiosis cases is occasionally attributed to healthy blood donors who were unaware of tick bites and Babesia infection. Therefore, there is an urgent need to investigate whether infections in humans have occurred in Japan.


Assuntos
Babesia/classificação , Babesiose/epidemiologia , Babesiose/parasitologia , Cervos/parasitologia , Animais , Ásia , DNA de Protozoário/genética , Ixodes/parasitologia , Japão/epidemiologia , Reação em Cadeia da Polimerase/métodos , Análise de Sequência de DNA
10.
Vet Parasitol ; 162(3-4): 241-7, 2009 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-19349121

RESUMO

We recently reported that feral raccoons (Procyon lotor) with splenomegaly native to Japan were carriers of a Babesia microti-like parasite identical to that found in the United States, which was likely introduced to Japan from North America via raccoons imported as pets. Thus, we attempted extensive molecular survey for piroplasma infections of feral raccoon with normal spleen in Hokkaido, Japan using nested PCR that target broadly to 18S ribosomal RNA gene (SSU-rDNA) of all the parasites in the genus Babesia, Theileria, Cytauxzoon and B. microti group. Of the 348 raccoon samples analyzed, 9 gave positive signals. Cloning and phylogenetic analysis on SSU-rDNA sequences revealed that six of nine positives were found to be infected with Babesia and the remaining three with previously unreported Sarcocystis. Babesia sequences were further separated into two distantly related groups, those that reside in a novel phylogenetic group were consisted solely of four parasites found in this study, while those which included one identical sequence found in the three of our specimens were assembled together with both Babesia parasites of tick's in Japan and of raccoon's in U.S. These results may indicate that not only a B. microti-like parasite but also at least two yet undescribed Babesia species are being established in their new life cycles in the feral raccoon populations in Japan.


Assuntos
Babesia/classificação , Babesiose/veterinária , Guaxinins/parasitologia , Animais , Babesia/genética , Babesiose/parasitologia , Japão/epidemiologia , Filogenia
11.
J Vet Med Sci ; 71(1): 55-68, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19194077

RESUMO

Babesia microti, the erythroparasitic cause of human babesiosis, has long been taken to be a single species because classification by parasite morphology and host spectrum blurred distinctions between the parasites. Phylogenetic analyses of the 18S ribosomal RNA gene (18S rDNA) and, more recently, the beta-tubulin gene have suggested inter-group heterogeneity. Intra-group relationships, however, remain unknown. This study was conducted to clarify the intra- and inter-group phylogenetic features of the B. microti-group parasites with the eta subunit of the chaperonin-containing t-complex polypeptide l (CCTeta) gene as a candidate genetic marker for defining the B. microti group. We prepared complete sequences of the CCTeta gene from 36 piroplasms and compared the phylogenetic trees. The B. microti-group parasites clustered in a monophyletic assemblage separate from the Babesia sensu stricto and Theileria genera and subdivided predominantly into 4 clades (U.S., Kobe, Hobetsu, Munich) with highly significant evolutionary distances between the clades. B. rodhaini branched at the base of the B. microti-group parasites. In addition, a unique intron presence/absence matrix not observable in 18S rDNA or beta-tubulin set the B. microti group entirely apart from either Babesia sensu stricto or Theileria. These results have strong implications for public health, suggesting that the B. microti-group parasites are a full-fledged genus comprising, for now, four core species, i.e., U.S., Kobe, Hobetsu, and Munich species nova. Furthermore, the CCTeta gene is an instructive and definitive genetic marker for analyzing B. microti and related parasites.


Assuntos
Babesia microti/classificação , Babesia microti/genética , Chaperoninas/genética , Filogenia , Sequência de Aminoácidos , Animais , Sequência de Bases , Chaperonina com TCP-1 , Análise por Conglomerados , Primers do DNA/genética , Mutação INDEL/genética , Dados de Sequência Molecular , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência , Especificidade da Espécie
12.
Exp Parasitol ; 120(3): 290-4, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18789933

RESUMO

Despite the evidence suggesting that mouse pyruvate kinase (PK) deficiency provides protection against malaria in rodents, there has been no investigation of a parallel protective effect against babesiosis caused by Babesia rodhaini. Here, we examined whether a PK-deficient co-isogenic mouse strain (CBA-Pk-1(slc)) was protected against B. rodhaini infection. We demonstrated that deficiency in pyruvate kinase correlated with a significant protective effect, with survival rates of 50%, 58% and 56% in groups inoculated with 10, 10(3) and 10(5) parasitized erythrocytes, respectively. In contrast, control CBA (CBA-Pk-1(+)) mice exhibited 100% lethality, regardless of the infectious dose. In addition, CBA-Pk-1(slc) mice showed decreased levels of parasitemia when compared to CBA-Pk-1(+) mice, in groups given 10, 10(3) or 10(5) parasitized erythrocytes. These results indicate that similar to PK deficiency in rodents, PK deficiency in mice affects the in vivo growth of B. rodhaini and protects the mice from lethal babesiosis.


Assuntos
Babesia/imunologia , Babesiose/imunologia , Piruvato Quinase/deficiência , Animais , Babesiose/enzimologia , Babesiose/parasitologia , Feminino , Camundongos , Camundongos Endogâmicos CBA , Parasitemia/enzimologia , Parasitemia/imunologia , Parasitemia/parasitologia
13.
Primates ; 49(1): 57-64, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17929110

RESUMO

We have examined the seroprevalence of BDV in wild Japanese macaques (Macaca fuscata) in the peninsula (Chiba prefecture), Japan. Serum samples from macaques were examined by the ELISA, Western blot and immunofluorescence assays to detect the presence of serum antibodies that react specifically to BDV antigens. Among 49 investigated individuals, 6 (12.2%) showed positive reaction to BDV antigens. RT-PCR studies detected BDV sequences in brain tissue of one case among four seropositive cases examined. Sequence analysis revealed a high degree of genetic conservation between BDV sequences derived from Japanese macaques and those documented for other animal species. Nevertheless, phylogenetic analysis revealed unique differences between macaque and other species derived BDV sequences.


Assuntos
Vírus da Doença de Borna/genética , Macaca/virologia , Filogenia , RNA Viral/isolamento & purificação , Animais , Sequência de Bases , Western Blotting , Análise por Conglomerados , Primers do DNA , Ensaio de Imunoadsorção Enzimática , Imunofluorescência , Japão , Dados de Sequência Molecular , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Alinhamento de Sequência , Análise de Sequência de DNA , Estudos Soroepidemiológicos
14.
J Vet Med Sci ; 68(7): 643-6, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16891774

RESUMO

Six Eurasian red squirrels (Sciurus vulgaris orientis), victims of road traffic found during 2002 and 2004 near the Noppro Forest Park in Ebetsu, Hokkaido, Japan, were examined for the presence of Babesia parasites. Three of the six squirrels exhibited positive signals by nested PCRs targeting both the 18S rRNA and beta-tubulin genes. Three squirrels proved to be infected with a B. microti-like parasite as evidenced by sequencing the amplified DNAs and by the morphology of the intraerythrocytic parasites. Genotypically, however, the parasite appeared to be of a new type, as it was clearly distinguishable from any of the known types that have previously been reported in various wild animals. This is the first report showing molecular evidence for the presence of B. microti-like parasites in Sciuridae.


Assuntos
Babesia microti/classificação , Babesia microti/isolamento & purificação , Sciuridae/parasitologia , Animais , Babesia microti/genética , DNA de Protozoário/genética , Japão , Filogenia , RNA Ribossômico 18S/genética
15.
AIDS ; 19(10): 1015-24, 2005 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-15958832

RESUMO

OBJECTIVE: Despite multiple and repeated exposures to HIV-1, some individuals possess no detectable HIV genome and show T-cell memory responses to the viral antigens. HIV-1-reactive mucosal IgA detected in such uninfected individuals suggests their possible immune resistance against HIV. We tested if the above HIV-1-exposed but uninfected status was associated with genetic markers other than a homozygous deletion of the CCR5 gene. METHODS: Based on our mapping in chromosome 15 of a gene controlling the production of neutralizing antibodies in a mouse retrovirus infection, we genotyped 42 HIV-1-exposed but uninfected Italians at polymorphic loci in the syntenic segment of human chromosome 22, and compared them with 49 HIV-1-infected and 47 uninfected healthy control individuals by a closed testing procedure. RESULTS: A significant association was found between chromosome 22q12-13 genotypes and a putative dominant locus conferring anti-HIV-1 immune responses in the exposed but uninfected individuals. Distributions of linkage disequilibrium across chromosome 22 also differed between the exposed but uninfected and two other phenotypic groups. CONCLUSIONS: The data indicated the presence of a new genetic factor associated with the HIV-1-exposed but uninfected status.


Assuntos
Cromossomos Humanos Par 22/genética , Infecções por HIV/genética , HIV-1/genética , Animais , Formação de Anticorpos , Linfócitos T CD4-Positivos/imunologia , Mapeamento Cromossômico , Cromossomos Humanos Par 15/genética , Feminino , Frequência do Gene , Genoma Viral , Genótipo , Anticorpos Anti-HIV/imunologia , Infecções por HIV/imunologia , Humanos , Memória Imunológica/genética , Itália/etnologia , Masculino , Camundongos , Repetições de Microssatélites , Carga Viral
16.
Vet Parasitol ; 127(2): 105-10, 2005 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-15631902

RESUMO

The spleen plays an important role in cellular immunity leading to parasite elimination, especially in hemo-protozoan parasite infection. In the present study, we quantified the serum IFN-gamma in splenectomized (SP) and non-splenectomized (NSP) cows infected with Theirelia sergenti (TS) to investigate whether the spleen plays a role in the Th1-type cytokine responses in cows following parasite infection. A transient increase in IFN-gamma was observed in the early stages of infection in the NSP cows, and the cows did not develop parasitemia. In contrast, the SP cows showed no IFN-gamma response at the early stage of infection, and the cows developed parasitemia following anemia. The NSP cows produced IgG1 and IgG2 antibodies to TS-specific, whereas the SP cows showed increases only in IgG1. Increased PBMC proliferation by cocanavalin A stimulation was observed concomitant with the IFN-gamma response. Pretreatment with IFN-gamma suppressed the propagation of TS in the SP cattle. These results suggest that the spleen plays an important role in the resistance to TS infection, leading to a Th1-type immune response. IFN-gamma might contribute to the activation of immunocytes and play an important role in the immune response to resist TS proliferation.


Assuntos
Doenças dos Bovinos/imunologia , Interferon gama/fisiologia , Baço/imunologia , Theileria/imunologia , Theileriose/imunologia , Animais , Anticorpos Antiprotozoários/sangue , Bovinos , Doenças dos Bovinos/sangue , Convalescença , Imunidade Celular , Interferon gama/imunologia , Interferon gama/metabolismo , Masculino , Parasitemia/imunologia , Parasitemia/veterinária , Baço/metabolismo , Células Th1/metabolismo , Theileria/patogenicidade , Theileriose/sangue
17.
J Vet Med Sci ; 67(9): 901-7, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16210802

RESUMO

Babesia rodhaini is a rodent hemoparasite closely related to B. microti, the major causative agent of human babesiosis. We tested the infectivity of B. rodhaini for human erythrocytes by using the SCID mouse model in which the circulating erythrocytes were replaced with those of humans. Initially, parasites grew very poorly in the mouse model, but a variant capable of propagating in human erythrocytes emerged after an adaptation period of three weeks. In an attempt to identify parasite proteins involved in the alteration of host cell preference, an expression cDNA library of B. rodhaini was constructed and screened with immune mouse sera. Although we were able to obtain three merozoite surface protein (MSP) genes, sequences of these genes from both the parental strain and human erythrocyte-adapted substrain were identical. Our results suggest that B. rodhaini has potential ability to infect human erythrocytes, but development of this ability may not be brought about by an amino acid change in MSPs.


Assuntos
Adaptação Biológica/genética , Babesia/genética , Eritrócitos/parasitologia , Proteínas de Protozoários/genética , Animais , Babesia/patogenicidade , Sequência de Bases , Primers do DNA , Biblioteca Gênica , Humanos , Soros Imunes , Camundongos , Camundongos SCID , Dados de Sequência Molecular , Proteínas de Protozoários/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência , Análise de Sequência de DNA
18.
J Vet Med Sci ; 67(8): 825-7, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16141672

RESUMO

Raccoons (Procyon lotor), which have recently become feral in Japan, were examined for the presence of Babesia microti-like parasites. Out of 372 raccoons captured in the west-central part of Hokkaido, 24 animals with splenomegaly were selected and tested by nested PCR targeting the babesial 18S rRNA gene. B. microti-like parasites were detected in two of the 24 individuals, and their DNA sequences were identical to that of the B. microti-like parasite reported from raccoons in the United States, suggesting that the parasites were probably imported into Japan and that the life cycle of the parasite has already been established in the country. The potential risk of this B. microti-like parasite spreading among dogs and foxes in Japan will need to be carefully monitored, as parasitization by phylogenetically very close parasites has been reported from such animals.


Assuntos
Babesia microti/genética , Babesiose/epidemiologia , Babesiose/veterinária , Carnívoros/parasitologia , Animais , Babesiose/parasitologia , Carnívoros/sangue , Primers do DNA , Japão/epidemiologia , Reação em Cadeia da Polimerase/veterinária , RNA Ribossômico 18S/genética , Esplenomegalia/parasitologia
19.
Vet Parasitol ; 120(4): 339-45, 2004 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-15063944

RESUMO

The 18S rRNA genes of Theileria species detected in sika deer, Cervus nippon centralis in Yamaguchi and Cervus nippon yesoensis in Hokkaido, were analyzed. The percent identities of the nucleotide sequences of Theileria from Cervus nippon centralis and Cervus nippon yesoensis were more than 99%. The percent identities of the Theileria sp. from sika deer and Theileria sergenti, Theileria buffeli and Theileria cervi were 97, 96 and 95%, respectively. Phylogenetic analysis of the gene sequences also revealed that Theileria sp. detected from sika deer comprise a clade that is clearly distinct from the clade comprised of Theileria from cattle.


Assuntos
Cervos/parasitologia , Theileria/genética , Theileriose/parasitologia , Animais , Sequência de Bases , DNA de Protozoário/química , DNA de Protozoário/genética , Japão , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase/veterinária , RNA Ribossômico 18S/química , RNA Ribossômico 18S/genética , Alinhamento de Sequência , Theileria/isolamento & purificação
20.
J Nutr Sci Vitaminol (Tokyo) ; 49(5): 346-9, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14703310

RESUMO

It has been known that Hyssopus officinalis (hyssop) is a herb that grows in the wild and is a source of natural antioxidants. We previously reported that a-glucosidase inhibitors, (2S, 3S)1-O-beta-D-6'-O-cinnamoylglucopyranosyl-3-(3", 5"-dimethoxy-4"-hydroxyphenyl)-1,2,3-propanetriol and (2S, 3S)1-O-beta-D-glucopranosyl-3-(3", 5"-dimethoxy-4"-hydroxyphenyl)-1,2,3-propanetriol, from the dry leaves of hyssop, were isolated. This study examined the alpha-glucosidase inhibitory effects of hyssop extracts on intestinal carbohydrate absorption in rat everted gut sac and carbohydrate-loaded hyperglycemia in mice. In the everted gut sac experiment, 10 mM sucrose- and 5 mM maltose-treated increases in glucose concentration in the serosal compartment were inhibited in the presence of 0.5 and 1.0 mg/ mL hyssop extracts, although a 10 mM glucose-induced increase in serosal glucose was not inhibited by the extracts. Additionally, hyperglycemia in sucrose- and maltose-loaded mice was significantly suppressed at an early stage, within 30 to 60 min by oral pre-administration of 300 and 100 mg/kg hyssop extracts, respectively. These findings suggest that hyssop extracts inhibited the digestion of complex carbohydrates, but not that of absorbable monosaccharide, and might be a useful supplemental food for hyperglycemia.


Assuntos
Inibidores Enzimáticos/farmacologia , Alimentos , Inibidores de Glicosídeo Hidrolases , Hiperglicemia/prevenção & controle , Intestinos/enzimologia , Lamiaceae/química , Extratos Vegetais/farmacologia , Animais , Metabolismo dos Carboidratos , Glucose/análise , Glucose/farmacologia , Absorção Intestinal/efeitos dos fármacos , Masculino , Maltose/administração & dosagem , Ratos , Ratos Wistar , Sacarose/administração & dosagem , alfa-Glucosidases/metabolismo
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