Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “BARTONELLA”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 523 records · Page 29Linked to original sources

Serology to Bartonella (Rochalimaea) henselae may replace traditional diagnostic criteria for cat-scratch disease.

Bartonella (Rochalimaea) henselae has been identified as causative agent of cat-scratch disease (CSD). Employing an indirect fluorescence antibody test we found that 20 (100%) out of 20 children with suspected CSD had serum titres to B. henselae of > or = 512. By contrast, in all but one of the controls (n = 332) including subjects exposed to the same cats, patients with diseases other than CSD, and blood donors the antibody titres were < or = 256 (P < 0.001). However, significant regional differences in seroprevalence were noted. CONCLUSION. Serology to B. henselae may supplant traditional criteria for the diagnosis of CSD and prevent patients from unnecessary surgery.

Adolescent↗

IgM to Bartonella henselae in cat-scratch disease and during acute Epstein-Barr virus infection.

The diagnostic value of IgM to Bartonella henselae was evaluated in 20 children with cat-scratch disease (CSD) and controls consisting of 20 blood donors and 20 children with enlarged lymph nodes without CSD by two indirect immunofluorescence assays (IFA). One was based on B. henselae cocultivated with Vero cells (host cell-associated IFA), and the other on B. henselae grown on agar (host cell-free IFA). With the host cell-associated IFA, 18 of 20 children with CSD revealed IgM, whereas only 14 did so with the host cell-free IFA. Sera of two blood donors as well as sera from three children with enlarged lymph nodes without CSD showed also positive IgM to cell-associated B. henselae. This study reveals that the IFA applied had sensitivities of 70-90% and specificities of 87.5-100% for detecting IgM to B. henselae. Additionally, 20 patients with IgM to Epstein-Barr virus (EBV) capsid antigen were tested for IgM to B. henselae. Sera of 16 and 9 of these patients revealed IgM to B. henselae with the host cell-associated and the host cell-free IFA, respectively. Using Western blot these sera were demonstrated to react against linearized proteins of Vero cells and of B. henselae. Thus, since acute EBV infection may substantially reduce the specificity of B. henselae-specific IgM tests, we conclude that diagnosis of CSD should be confirmed by a significant IgG titer to B. henselae or by detection of this pathogen.

Animals↗

[Solitary nontuberculous mycobacterial infection of a cervical lymph node caused by Bartonella henselae (cat scratch disease)].

Cat scratch disease (CSD) is a common cause of subacute regional lymphadenopathy. Cats are the principal reservoir of Bartonella henselae, the etiologic agent in most cases of CSD. Because the histopathological findings are typical but not specific, a wide range of other agents must be considered in differential diagnosis. We report on a patient with a solitary swelling of the neck which remained over months with initial features suggestive of unspecific lymphadenitis, but who, after careful history taking and further serological testing, had cat scratch disease.

Abscess↗

Purification of deformin, an extracellular protein synthesized by Bartonella bacilliformis which causes deformation of erythrocyte membranes.

A factor capable of deforming erythrocyte membranes, found in the culture supernatants of Bartonella bacilliformis, was purified 1840-fold using hydrophobic, ion exchange and gel exclusion chromatography. The final fractions contained a single detectable polypeptide species, referred to as deformin, having a molecular weight of 67000 by SDS-PAGE and a native molecular weight of 130,000 by gel exclusion chromatography or velocity sedimentation in a glycerol gradient. Erythrocytes treated with deformin acquire trenches, indentations, and invaginations which could be reversed by vanadate, dilauroylphosphatidylcholine (DLPC), or by raising the internal Ca2+ concentrations with the inophore A23187. Internal vacuoles also form. Erythrocytes treated with trypsin or neuraminidase are much more sensitive to deformin than untreated erythrocytes; erythrocytes treated with phospholipase D are less sensitive to deformin. This protein may play a role in causing the severe anemia which can result as a consequence of infection by B. bacilliformis.

Bacterial Proteins↗

Bartonella bacilliformis or a similar organism and cardiovascular disease.

Bartonella bacilliformis invades the endothelial lining of the cardiovascular system. Damage to the red blood cells and white blood cells, the effects of the toxins, invasion of the brain and electrical charges induced by the organism so interfering with normal electrical stimulation of the heart may explain many of the features of cardiovascular disease (1-5).

Bartonella Infections↗

Taxonomic considerations of Bartonella bacilliformis based on phylogenetic and phenotypic characteristics.

The 16S-rRNA gene of Bartonella bacilliformis was amplified using the polymerase-chain reaction (PCR). The amplification product was sequenced using a linear-PCR procedure and compared with other published 16S-rRNA sequences. The results of this analysis placed B. bacilliformis in the alpha subgroup of the proteobacteria, and more specifically demonstrated its close phylogenetic relationship to Rochalimaea quintana. This relationship is supported by similarities in the size and mean base composition of the genomes of the two species, and by shared phenotypic characteristics.

Bartonella↗

Characterization of the fMet initiator tRNA gene of Bartonella bacilliformis.

A ribosomal RNA operon was cloned from the agent of human Oroya fever, Bartonella bacilliformis. The 3' end of the operon contains a 77-nucleotide (nt) N-formylmethionine (fMet) initiator tRNA-encoding gene with 100% sequence identity to the fMet tRNA-encoding gene of Rhodobacter sphaeroides. The 3' region downstream from the gene has an 8-nt inverted repeat and 28 contiguous direct repeats of the heptamer 5'-TTCTCTA. To date, B. bacilliformis and R. sphaeroides are the only known eubacteria which have an fMet tRNA-encoding gene within the 3' end of their rRNA operons.

Bartonella↗

Characterization of the 16S-23S rRNA intergenic spacer of Bartonella bacilliformis.

The 16S-23S intergenic spacer region from the ribosomal RNA (rRNA) operon of Bartonella bacilliformis was cloned and characterized. The spacer is 906 nucleotides (nt) in length and contains the genes encoding isoleucine-tRNA (tRNA(Ile)) and alanine-tRNA (tRNA(Ala)). The tRNA-encoding genes are separated by 122 nt and are centrally located in the 16S-23S spacer region, with approx. 300 flanking nt. Genes encoding tRNA(Ile) and tRNA(Ala) have 88.3 and 93.4% sequence identity, respectively, to the homologous genes of Rhodobacter sphaeroides.

Bartonella↗

Nucleotide sequence analysis of the 23S ribosomal RNA-encoding gene of Bartonella bacilliformis.

We report the cloning and characterization of the 23S ribosomal RNA (rRNA)-encoding gene (rDNA) of Bartonella bacilliformis (Bb). The 2821-bp gene is preceded by an 11-nucleotide (nt) inverted repeat (IR) located 81 nt upstream in the tRNA(Ala)-23S rDNA intergenic spacer. The gene is followed by an 8-nt IR, five nt downstream in the 23S-5S rDNA intergenic spacer. The nt sequence of the Bb 23S rDNA is most similar to the 23S rDNA of Rhodopseudomonas palustris (Rp), with 85.4% sequence identity. The Bb 23S rDNA has 77.8% identity to the same gene from Escherichia coli (Ec). Secondary structure predictions indicate that the large subunit (LSU) Bb rRNA contains two smaller stem-loops at nt 1459-1544 and 1658-1685, as compared to the corresponding loops from Ec (nt 1405-1597 and 1707-1751, respectively). In addition, the Bb 23S rRNA has a large 72-nt stem-loop at nt 130-201, as compared to the Ec 18-nt stem-loop (nt 131-148). There is no Bb homologue of the 15-nt stem-loop at the 3' end of the Ec molecule (nt 2791-2805). The Bb 23S rRNA lacks the large stem-loop present in the LSU rRNA of closely related Rhodobacter sphaeroides (Rs) (nt position 1225-1331) which is thought to be involved in cleavage of 23S RNA precursor molecules into 16S and 14S rRNA species. This is the first LSU rDNA nt sequence for any member of the Bartonellaceae family.

Bartonella↗

Cloning, expression and sequence analysis of the Bartonella henselae gene encoding the HtrA stress-response protein.

A cloned fragment of Bartonella (Rochalimaea) henselae (Bh) DNA was found to direct synthesis of an immunoreactive protein in Escherichia coli (Ec). Sequence analysis revealed an open reading frame of 1509 nucleotides encoding a protein of 503 amino acids that exhibited extensive identity (over the entire protein) with the HtrA stress-response proteins of Brucella abortus (59%), Ec (37%) and Salmonella typhimurium (36%). When the putative htrA gene was amplified by polymerase chain reaction and used as template for in vitro transcription and translation, a protein with an apparent molecular mass of 62 kDa was synthesized from the plasmid template. These results suggest that the immunoreactive Bh protein is homologous to the HtrA class of stress-response proteins.

Bartonella henselae↗

Role of Bartonella henselae endocarditis in the nucleation of aortic valvular calcification.

A 6-year-old boy presented with fatigability, shortness of breath, and bulging neck veins. Echocardiography revealed large vegetations, aortic insufficiency, a dilated left ventricle, and bicuspid aortic valve. There was no history of immunocompromise, fevers, or feline exposures. Blood cultures were negative; antibodies against Bartonella henselae were positive. Gentamicin was administered intravenously. Ross procedure was performed and patient was discharged on antibiotics in 5 days. Native valve was thickened by scar and fibrinous vegetations. Warthin-Starry stain demonstrated coccobacilli. Light and ultrastructural morphology, and monoclonal staining implicated B. henselae. Bacterial membranes contain calcium apatite crystals. Antigenic material was present in bacteria and calcified nodules. This case illustrates calcified protobacteria becoming incorporated into scar tissue during endocarditis.

Angiomatosis, Bacillary↗

Prevalence of Bartonella henselae antibodies in serum of cats with and without clinical signs of central nervous system disease.

Bartonella henselae is occasionally associated with neurological dysfunction in people and some experimentally infected cats. The purpose of this study was to determine whether B henselae seroprevalence or titer magnitude varies among cats with neurological disease, cats with non-neurological diseases, and healthy cats while controlling for age and flea exposure. There was no difference in B henselae seroprevalence rates between cats with seizures and cats with other neurological diseases. Cats with non-neurological disease and healthy cats were more likely than cats with neurological disease to be seropositive. While the median B henselae antibody titer was greater in cats with seizures than in cats with other neurological disease, the median B henselae antibody titer was also greater in healthy cats than cats with seizures. The results suggest that titer magnitude cannot be used alone to document clinical disease associated with B henselae infection and that presence of B henselae antibodies in serum of cats with neurological disease does not prove the clinical signs are related to B henselae.

Animals↗

Rapid detection and differentiation of Bartonella spp. by a single-run real-time PCR.

A Real-time PCR for the identification and differentiation of Bartonella spp. based on the detection of mutations in an internal region of the gltA gene by thermal analysis was developed. The assay included a simultaneous detection of the amplicons by direct hybridization of LCRed and fluorescein-labelled probes coupled with melting curve analysis by the use of fluorescence resonance energy transfer technology. The protocol allowed establishing genospecie identity in less than 1 h without a need for restriction enzyme digestion or gel electrophoresis. The method is simple, reproducible, rapid, specific and potentially transferable to clinical samples.

Bartonella↗

Emergence of distinct genetic variants in the population of primary Bartonella henselae isolates.

Bartonella henselae isolates from different hosts display a marked genetic heterogeneity, as determined by pulsed-field gel electrophoresis (PFGE). The aim of the present study was to determine whether different genetic variants may coexist within the population of distinct B. henselae isolates and could be detected by PFGE. Three primary B. henselae isolates and the B. henselae reference strains ATCC 49793 and 49882 were subjected as single colony derived cultures in quadruplicate to PFGE analysis upon restriction with SmaI or NotI. Up to 4 fragment differences were found among the cultures obtained from each primary isolate, indicating the coexistence of genetic variants in the population of primary B. henselae isolates. The clonal relatedness of the genetic variants was confirmed by arbitrarily primed PCR and multi-locus sequence typing. In contrast to the primary isolates, no variants were detected among the single colony derived cultures of the high-passage ATCC strains. We hypothesized that the coexistence of different genetic variants may represent a feature that is restricted to primary or low-passage B. henselae isolates. The primary isolates were serially passed in vitro and then subjected as single colony derived cultures to PFGE analysis, which now revealed identical patterns among the quadruplicate cultures of each high-passage isolate. These results suggest that the population of a primary B. henselae isolate is composed of distinct genetic variants, which may disappear upon repeated passages on artificial culture media. Generation of genetic variants by B. henselae may represent an escape mechanism to circumvent the host specific immune responses.

Angiomatosis, Bacillary↗

Binding of Bartonella henselae to extracellular molecules: identification of potential adhesins.

Bartonella henselae, the etiologic agent of cat scratch disease, bacillary angiomatosis and other clinical syndromes initiates infection through a trauma or wound to the skin suggesting involvement of extracellular matrix molecules. We have demonstrated in this study that B. henselae bound strongly fibronectin, collagen IX and X, but comparatively less laminin and collagen IV. B. henselae bound primarily the N- and C-terminal heparin (Hep-1 and Hep-2, respectively) and the gelatin-binding domains of fibronectin (Fn) but not the cell-binding domain. Binding to the Hep-binding domain was significantly inhibited by Hep suggesting common binding sites on the Fn molecule. Furthermore, glycosaminoglycans-mediated binding of B. henselae to soluble Fn showed that Hep but not dextran sulfate inhibited the bacterium binding to Fn. Unlike Fn, B. henselae bound strongly vitronectin only in the presence of Hep or dextran sulfate. Also, the binding of B. henselae to host cells could be inhibited by anti-B. henselae surface-reactive antibodies, the exogenous Fn or the anti-Fn polyclonal antibodies. Ligand blots, batch affinity purification and MALDI-TOF peptide fingerprinting identified B. henselae Pap31, Omp43 and Omp89 as the three major putative Fn-binding proteins (FnBPs) in B. henselae outer membrane proteins. We hypothesized that B. henselae wound associated infections involved interactions with extracellular matrix molecules. Taken together, the above data suggest that interactions between B. henselae and ECM molecules such as Fn may play an important role in the bacterium adherence to and invasion of host cells.

Adhesins, Bacterial↗

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↗