| genetic classification of "rickettsia heilongjiangii" and "rickettsia hulinii," two chinese spotted fever group rickettsiae. | to determine the phylogenetic position of two new rickettsial strains isolated from ticks in china, 16s ribosomal dna, glta, and ompa (apart from the tandem repeat units) genes were amplified by pcr and sequenced. the phylogenetic relationships between these strains and other rickettsiae were inferred from the comparison of sequences of the three genes by the parsimony, neighbor-joining, and maximum-likelihood methods. the results demonstrated that the 054 strain, a rickettsia pathogenic in huma ... | 2000 | 10970415 |
| gene sequence-based criteria for identification of new rickettsia isolates and description of rickettsia heilongjiangensis sp. nov. | we propose genetic guidelines for the classification of rickettsial isolates at the genus, group, and species levels by using sequences of the 16s rrna (rrs) gene and four protein-coding genes, the glta, ompa, and ompb genes and gene d. to be classified as a member of the genus rickettsia, an isolate should exhibit degrees of rrs and glta homology with any of the 20 rickettsia species studied of >/=98.1 and >/=86.5%, respectively. a member of the typhus group should fulfill at least two of the f ... | 2003 | 14662925 |
| detection of a rickettsia closely related to rickettsia aeschlimannii, "rickettsia heilongjiangensis," rickettsia sp. strain rpa4, and ehrlichia muris in ticks collected in russia and kazakhstan. | using pcr, we screened 411 ticks from four genera collected in russia and kazakhstan for the presence of rickettsiae and ehrlichiae. in russia, we detected "rickettsia heilongjiangensis," rickettsia sp. strain rpa4, and ehrlichia muris. in kazakhstan, we detected rickettsia sp. strain rpa4 and a rickettsia closely related to rickettsia aeschlimannii. these agents should be considered in a differential diagnosis of tick-borne infections in these areas. | 2004 | 15131195 |
| acute tick-borne rickettsiosis caused by rickettsia heilongjiangensis in russian far east. | an acute tick-borne rickettsiosis caused by rickettsia heilongjiangensis was diagnosed in 13 patients from the russian far east in 2002. we amplified and sequenced four portions of three rickettsial genes from the patients' skin biopsy results and blood samples and showed that the amplified rickettsial genes belong to r. heilongjiangensis, which was recently isolated from dermacentor sylvarum ticks in nearby regions of china. this rickettsia, belonging to subgroup of r. japonica, was previously ... | 2004 | 15200813 |
| analysis of immunoprotectivity of the recombinant ompa of rickettsia heilongjiangensis. | a truncated gene ompa was amplified from rickettsia heilongjiangensis isolated in china and a 56-kda truncated ompa protein was expressed in e. coli cells transformed with the ompa-recombined expression plasmid. high levels of serum antibodies to r. heilongjiangensis and proliferation of the splenic cells were found in mice immunized with the truncated ompa. after challenge with r. heilongjiangensis or r. rickettsii, fever and pathological damages of the guinea pigs immunized with the truncated ... | 2005 | 16481525 |
| far eastern tick-borne rickettsiosis: identification of two new cases and tick vector. | we recently reported the first documented cases of a new rickettsial disease caused by rickettsia heilongjiangensis in the russian far east (far eastern tick-borne rickettsiosis). here we report the amplification of dna of r. heilongjiangensis from both the skin biopsy of an acutely ill patient and the tick removed from him prior to the disease development. the tick has been identified as haemaphysalis spp. the clinical picture was that of a spotted fever group rickettsiosis and a seroconversion ... | 2006 | 17114683 |
| [far-eastern spotted fever: description of new infectious disease]. | historical data concerning description and identification of etiology of tick-borne spotted fever in russia are presented in the paper. review of studies shows that by uncovering the etiology of tick-borne spotted fever in the russian far east, an emerging disease may be discovered. another, different from classical rickettsia sibirica, bacteria causes spotted fever there. the application of described methods resulted in first isolation of etiological agent of far-eastern spotted fever, ricketts ... | 2008 | 18756784 |
| 'rickettsia hulinii' belongs to the rickettsia heilongjiangensis species. | | 2009 | 19438613 |
| identification of a new serotype of rickettsia heilongjiangensis in wild rats from guangdong province, china. | | 2009 | 19438614 |
| isolation of rickettsia heilongjiangensis strains from humans and ticks and its multispacer typing. | | 2009 | 19438658 |
| dissemination of spotted fever rickettsia agents in europe by migrating birds. | migratory birds are known to play a role as long-distance vectors for many microorganisms. to investigate whether this is true of rickettsial agents as well, we characterized tick infestation and gathered ticks from 13,260 migratory passerine birds in sweden. a total of 1127 ixodes spp. ticks were removed from these birds and the extracted dna from 957 of them was available for analyses. the dna was assayed for detection of rickettsia spp. using real-time pcr, followed by dna sequencing for spec ... | 2010 | 20052286 |
| detection of spotted fever group rickettsia spp. from bird ticks in the u.k. | migratory birds are known to play a role in the long-distance transportation of microorganisms. to investigate whether this is true for rickettsial agents, we undertook a study to characterize tick infestation in populations of the migratory passerine bird riparia riparia (passeriformes: hirundinidae), the sand martin. a total of 194 birds were sampled and ticks removed from infested birds. the ticks were identified as female ixodes lividus (acari: ixodidae) using standard morphological and mole ... | 2010 | 20546129 |
| human rickettsia heilongjiangensis infection, japan. | a case of rickettsia heilongjiangensis infection in japan was identified in a 35-year-old man who had rash, fever, and eschars. serum contained r. heilongjiangensis antibodies, and eschars contained r. heilongjiangensis dna. r. heilongjiangensis was also isolated from ticks in the suspected geographic area of infection. | 2010 | 20678332 |
| molecular survey of rickettsial agents in feral raccoons (procyon lotor) in hokkaido, japan. | rickettsial infection in feral raccoons (procyon lotor) in hokkaido, japan was analyzed by molecular methods. genus-specific nested polymerase chain reaction (pcr) analysis based on the rickettsia citrate synthase (glta) gene showed that 13 of 699 raccoons (1.9%) examined were positive for rickettsia. twelve of the 13 partial glta sequence amplicons were successfully analyzed. the nucleotide sequence of one amplicon was identical to both rickettsia heilongjiangensis and r. japonica, one was iden ... | 2010 | 20859004 |
| detection of spotted fever group rickettsia in haemaphysalis longicornis in hebei province, china. | abstract dna samples from 737 ticks pools, representing 6850 haemaphysalis longicornis and 51 dermacentor nuttalli ticks collected from hebei province, china, were analyzed by pcr for the presence of spotted fever group rickettsia. there were 50 (6.9%) of 724 h. longicornis ticks pools found positive, but no positive samples found in 13 d. nuttalli. sequence analysis of the partial outer membrane protein a (ompa) genes from the ten positive samples showed 98% identity, but different from the hom ... | 2011 | 21506802 |
| Complete genome sequence of Rickettsia heilongjiangensis, an emerging tick-transmitted human pathogen. | Rickettsia heilongjiangensis is an emerging tick-transmitted human pathogen causing far-Eastern spotted fever. Here we report the complete sequence and the main features of the genome of R. heilongjiangensis (strain 054). | 2011 | 21914880 |
| exploratory study on pathogenesis of far-eastern spotted fever. | far-eastern spotted fever is an emerging disease caused by rickettsia heilongjiangensis, a tick-borne obligate intracellular bacterium. in this study, r. heilongjiangensis was used to infect balb/c mice by inoculation of retro-orbital venous plexus to imitate a blood infection caused by tick biting. we found that r. heilongjiangensis rapidly entered the circulation for systemic dissemination and the pathogen existed in liver, spleen, lungs, and brain of the mice at least 9 days post-infection (p ... | 2011 | 21896812 |
| characterization of rickettsiae in ticks in northeastern china. | tick-borne rickettsioses are considered important emerging zoonoses worldwide, but their etiological agents, rickettsiae, remain poorly characterized in northeastern china, where many human cases have been reported during the past several years. here, we determined the characteristics of rickettsia spp. infections in ticks in this area. | 2016 | 27623998 |
| detection of spotted fever group rickettsiae in ticks from zhejiang province, china. | tick species distribution and prevalence of spotted fever group rickettsiae (sfgr) in ticks were investigated in zhejiang province, china in 2010 and 2011. pcr was used to detect sfgr and positive amplicons were sequenced, compared to published sequences and phylogenic analysis was performed using mega 4.0. a total of 292 adult ticks of ten species were captured and 7.5 % (22/292) of the ticks were pcr-positive for sfg rickettsia. the pcr-positive rates were 5.5 % (6/110) for haemaphysalis longi ... | 2015 | 25633265 |
| rickettsia vini n. sp. (rickettsiaceae) infecting the tick ixodes arboricola (acari: ixodidae). | recently, a new rickettsia named 'candidatus rickettsia vini' belonging to the spotted fever group has been molecularly detected in ixodes arboricola ticks in spain, the czech republic, slovakia and turkey, with prevalence reaching up to 100 %. the aim of this study was to isolate this rickettsia in pure culture, and to describe it as a new rickettsia species. | 2016 | 27565956 |
| proteome analysis and serological characterization of surface-exposed proteins of rickettsia heilongjiangensis. | rickettsia heilongjiangensis, the agent of far-eastern spotted fever (fesf), is an obligate intracellular bacterium. the surface-exposed proteins (seps) of rickettsiae are involved in rickettsial adherence to and invasion of host cells, intracellular bacterial growth, and/or interaction with immune cells. they are also potential molecular candidates for the development of diagnostic reagents and vaccines against rickettsiosis. | 2013 | 23894656 |
| genetic variability of rickettsia spp. in ixodes persulcatus ticks from continental and island areas of the russian far east. | rickettsia spp. are intracellular gram-negative bacteria transmitted by arthropods. two potentially pathogenic rickettsiae, candidatus rickettsia tarasevichiae and rickettsia helvetica, have been found in unfed adult ixodes persulcatus ticks. the aim of this study was to assess the prevalence and genetic variability of rickettsia spp. in i. persulcatus ticks collected from different locations in the russian far east. in total, 604 adult i. persulcatus ticks collected from four sites in the khaba ... | 2016 | 27424272 |
| diversity of spotted fever group rickettsia infection in hard ticks from suifenhe, chinese-russian border. | in order to investigate the diversity of spotted fever group (sfg) rickettsia infection in hard ticks, ticks were harvested from the forest areas in suifenhe city, along the chinese-russian border and conventional pcr was carried out using universal sfg rickettsia primers targeting glta and ompa genes to screen for their infection with sfg rickettsia organisms. results showed that of the 215 ticks belonging to ixodes persulcatus, haemaphysalis concinna and haemaphysalis japonica warburton, 1908 ... | 2016 | 26976703 |
| enhanced expression of t-cell immunoglobulin and mucin domain protein 3 in endothelial cells facilitates intracellular killing of rickettsia heilongjiangensis. | rickettsia heilongjiangensis is the pathogen of far eastern spotted fever, and t-cell immunoglobulin and mucin domain protein 3 (tim-3) is expressed in human vascular endothelial cells, the major target cells of rickettsiae. in the present study, we investigated the effects of altered tim-3 expression in vivo in mice and in vitro in human endothelial cells, on day 3 after r. heilongjiangensis infection. compared with corresponding controls, rickettsial burdens both in vivo and in vitro were sign ... | 2016 | 26401029 |
| new evidence on tick-borne rickettsioses in the altai region of russia using primary lesions, serum and blood clots of molecular and serological study. | tick-borne rickettsioses (tbrs) have similar clinical symptoms and can give serological cross-reaction. we firstly found that in the natural foci of north asian tick typhus (natt) in the altai region of russia, tbrs can be caused by two rickettsia species: rickettsia sibirica subsp. sibirica (causative agent of natt) and rickettsia heilongjiangensis. rickettsial dna was detected in primary lesions, serum samples and blood clots using real-time pcr. therefore, each case of tbrs should be verified ... | 2016 | 26344602 |
| molecular characterization of 'candidatus rickettsia vini' in ixodes arboricola from the czech republic and slovakia. | the aim of this study was to analyze the prevalence of rickettsiae in the tree-hole tick ixodes arboricola in the czech republic and slovakia. during may to september of 2009 and 2013, bird boxes belonging to three different areas were screened for ticks. in total, 454 nestlings and 109 nests of 10 hole-breeding bird species were examined. ticks were found on ficedula albicollis, parus major, cyanistes caeruleus and sitta europaea and/or in their nests. in total, 166 ticks (17 nymphs, 10 males a ... | 2015 | 25769386 |
| protective immunity against rickettsia heilongjiangensis in a c3h/hen mouse model mediated by outer membrane protein b-pulsed dendritic cells. | rickettsia heilongjiangensis is an obligate intracellular bacterium that causes far-eastern tick-borne spotted fever. outer membrane protein b (ompb) is an important surface protein antigen of rickettsiae. in the present study, the ompb gene of r. heilongjiangensis was divided into four fragments, resulting in four recombinant proteins (ompb-p1, ompb-p2, ompb-p3, and ompb-p4). each ompb was used in vitro to stimulate murine bone marrow-derived dendritic cells (bmdcs) of c3h/hen mice, and the omp ... | 2015 | 25270001 |
| microarray of surface-exposed proteins of rickettsia heilongjiangensis for serodiagnosis of far-eastern spotted fever. | far-eastern spotted fever (fesf) is an important emerging infectious disease in northeast asia. the laboratory diagnosis of fesf in hospitals is mainly based on serological methods. however, these methods need to cultivate rickettsial cells as diagnostic antigens, which is both burdensome and dangerous. | 2014 | 24938647 |
| genomic and comparative genomic analyses of rickettsia heilongjiangensis provide insight into its evolution and pathogenesis. | rickettsia heilongjiangensis, the causative agent of far eastern spotted fever, is an obligate intracellular gram-negative bacterium that belongs to the spotted fever group rickettsiae. to understand the evolution and pathogenesis of r. heilongjiangensis, we analyzed its genome and compared it with other rickettsial genomes available in genbank. the r. heilongjiangensis chromosome contains 1333 genes, including 1297 protein coding genes and 36 rna coding genes. the genome also contains 121 pseud ... | 2014 | 24924907 |
| recombinant protein ybgf induces protective immunity against rickettsia heilongjiangensis infection in c3h/hen mice. | surface proteins ybgf and prsa are major seroreactive antigens of rickettsia heilongjiangensis, the etiological agent of far-eastern spotted fever. this study investigated their potential immunogenicity for protective immunity. | 2013 | 24113261 |