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PubMed2000

Imaging of rickettsial, spirochetal, and parasitic infections.

This article reviews the clinical signs, symptoms, and neuroimaging findings of the commonly known rickettsial, spirochetal, and parasitic infections (cysticercosis is covered elsewhere in this issue). Differential diagnoses and significant imaging characteristics are reviewed to help narrow the diagnostic possibilities. Several of the infections in this disparate group are not seen as commonly as they once were because of advances in early diagnosis, treatment, improvements in sanitation, and prevention of epidemics. Many of the infections, however, are endemic to certain parts of the world and are seen with increasing frequency in immunocompromised individuals.

Brain↗
PubMedDate not supplied

[Serotyping of strains of Serpulina hyosenteriae isolated form swine with porcine dysentery symptoms in the province of Buenos Aires].

Seventeen Serpulina hyodysenteriae strains isolated from faeces, rectal swabs and intestinal contents of pigs with Swine Dysentery, from farms located in Buenos Aires province were serotyped. Samples on selective media (trypticase soy agar added by 5% ovine blood, 400 mg/l spectinomicin, 30 mg/l colistin, 30 mg/l vancomycin) were streaked and incubated under anaerobic atmosphere for 72 h at 42 degrees C. Suspected S. hyodysenteriae growth were identified by strong beta-hemolytic zone, without colonies, and the spirillar morphology, using the Victoria Blue 4-R stain were criteria following by S. hyodysenteriae preliminar identification. The following antigens were made by phenolic extraction from a concentrated inocula washed twice in PBS pH 7: whole-cell (WC), boiled cell (BC) and lipopolysaccharide (LPS). Two serological test were: coagglutination and immunodiffusion, using polyclonal rabbit antisera against the 9 serotypes of S. hyodysenteriae and S. innocens, using WC and BC like antigens for the first test and BC and LPS for the second. The Dot-ELISA Test was performed using BC and LPS antigens and monoclonal antibodies (AbM) against serotypes 1, 2, 3, 8, 9 of S. hyodysenteriae, AbM species-specific and AbM against S. innocens. All isolated S. hyodysenteriae strains belonged to serotype 8. Like in other countries occurred, it would exit a high regional prevalence of S. hyodysenteriae serotype, being the serotype 8 in Argentine.

Agglutination Tests↗
PubMed1998

Cosmopolitan distribution of the large composite microbial mat spirochete, Spirosymplokos deltaeiberi.

Inocula from organic-rich black muds immediately underlying intertidal laminated microbial mats dominated by Microcoleus chthonoplastes yielded large, variable diameter spirochetes. These unusual spirochetes, previously reported only from the Alfacs Peninsula at the delta of the Ebro river in northeast Spain, contain striking arrays of cytoplasmic granules packed into their protoplasmic cylinders. On several occasions, both in summer and winter, the huge spirochetes were recognized in samples from mats growing in the Sippewissett salt marsh at Woods Hole Massachusetts. They were also seen in similar samples from microbial mats at North Pond, Laguna Figueroa, Baja California Norte, Mexico. The identity of these spirochetes was confirmed by electron microscopy: number and disposition of flagella, composite structure, measurements of their distinctive cytoplasmic granules. The granules, larger, more conspicuous and present in addition to ribosomes, are hypothesized to contain ATPases. As culture conditions worsen, these spirochetes retract into membrane-bounded round bodies in which they form refractile inclusions. From morphology and behavior we conclude the North American spirochetes from both Atlantic and Pacific intertidal microbial mats are indistinguishable from those at the delta of the Ebro river. We conclude a cosmopolitan distribution for Spirosymplokos deltaeiberi.

Massachusetts↗
PubMed2000

Detection of same sized 4.3 Kb extrachromosomal DNA elements in weakly beta-haemolytic human intestinal spirochaetes and Serpulina pilosicoli of swine origin.

Agarose gel electrophoresis of total DNA from Italian strains of weakly beta-haemolytic human intestinal spirochaetes (w beta HIS) and porcine Serpulina pilosicoli reference strain P43/6/78 showed an extrachromosomal band having the same size and migrating at 4.3 Kb. The same results were observed after agarose gel electrophoresis of DNA obtained from the supernatant fluids of the spirochaetal cultures analysed. Swine Serpulina hyodysenteriae reference strain P18A was comparatively analysed and a 6.5 Kb extrachromosomal DNA element was found, as expected. Furthermore, S. hyodysenteriae reference strain P18A differed from all the other spirochaetes tested and had a higher number of flagella (8-12) at each cell end and was strongly beta-haemolytic. To the best of our knowledge, this is the first report on the detection of a band of extrachromosomal DNA having the same size in w beta HIS and S. pilosicoli from swine origin.

Animals↗
PubMed2000

Phylogenetic foundation of spirochetes.

The spirochetes are free-living or host-associated, helical bacteria, some of which are pathogenic to man and animal. Comparisons of 16S rRNA sequences demonstrate that the spirochetes represent a monophyletic phylum within the bacteria. The spirochetes are presently classified in the Class Spirochaetes in the order Spirochetales and are divided into three major phylogenetic groupings, or families. The first family Spirochaetaceae contains species of the genera Borrelia, Brevinema, Cristispira, Spirochaeta, Spironema, and Treponema. The second family Brachyspiraceae contains the genus Brachyspira (Serpulina). The third family Leptospiraceae contains species of the genera Leptonema and Leptospira. Novel spirochetal species, or phylotypes, that can not be presently cultivated in vitro, have been identified from the human oral cavity, the termite gut, and other host-associated or free-living sources. There are now over 200 spirochetal species or phylotypes, of which more than half is presently not cultivable. It is likely that there is still a significant unrecognized spirochetal diversity that should be evaluated.

Borrelia↗
PubMed2000

Chemotaxis in pathogenic spirochetes: directed movement toward targeting tissues?

Chemotaxis is an important feature of motile organisms that allows navigation through various environments. It enables them to detect nutrients and to avoid unfavorable or dangerous conditions. Motility and chemotaxis are widely acknowledged as important virulence factors for pathogenic bacteria. In this review, we try to explore the role of chemotaxis in the pathogenesis of spirochetes. Chemotaxis might be involved in tissue identification and penetration, and represents a possible mechanism for evasion of the host's immune defense. The recent development of genetic tools for pathogenic spirochetes and "tracking" techniques, employing fluorescent in situ hybridization (FISH), could revolutionize our understanding of the importance of chemotaxis for infection and persistence of these bacteria in their host.

Animals↗
PubMed2000

Bacteriophages of spirochetes.

Historically, a number of bacteriophage-like particles have been observed in association with members of the bacterial order Spirochetales, the spirochetes. In the last decade, several spirochete bacteriophages have been isolated and characterized at the molecular level. We have recently characterized a bacteriophage of the Lyme disease agent, Borrelia burgdorferi, which we have designated phiBB-1. Here we review the history of the association between the spirochetes and their bacteriophages, with a particular emphasis on phiBB-1 and its prophage, the 32-kb circular plasmid family of B. burgdorferi.

Bacteriophages↗
PubMed2000

Genome analyses of spirochetes: a study of the protein structures, functions and metabolic pathways in Treponema pallidum and Borrelia burgdorferi.

We perform a comprehensive genome analysis on two spirochetes, T. pallidum and B. burgdorferi. First, we focus on the occurrence of protein structures in these organisms. We find that there are only a few spirochete-specific folds, relative to those in other types of bacteria. The most common fold, by far, in the spirochetes is the P-loop NTP hydrolase, followed by the TIM barrel. These folds also happen to be amongst the most multifunctional of the known folds. We also survey the membrane-protein structures in T. pallidum and find a notable large family with twelve transmembrane (TM) helices, reflecting the prevalence of 12-TM transporters in bacteria. Then we move to analysis of the metabolic pathways and overall metabolism in the spirochetes, using the metabolic-flux-balancing method. We find that the lipid biosynthesis pathway is absent from the spirochetes. This strongly limits the degree to which these organisms can metabolize NADPH. In turn, we find that the spirochetes distribute flux disproportionately through the glycolytic pathway instead of the NADPH-providing pentose phosphate pathway. Further information is available at http://bioinfo.mbb.yale.edu

Bacterial Proteins↗
PubMed2000

Whole genome analyses of transporters in spirochetes: Borrelia burgdorferi and Treponema pallidum.

The completely sequenced genomes of two spirochetes, Borrelia burgdorferi(Bbu) and Treponema pallidum (Tpa) were analyzed for the distribution of transporter types. Both organisms exhibited fewer proteins with >7 alpha-helical transmembrane spanners (TMSs), and fewer identified transport systems per megabase pair of DNA than most other prokaryotes analyzed. Each organism exhibits one recognizable ion channel protein of the MscS family. Tpa has twice as many primary carriers as Bbu but lacks PTS permeases that are plentiful in Bbu. Tpa is the only prokaryote so far sequenced which has two F-type ATPases. Large families of secondary nutrient uptake carriers (MFS and APC) that are prevalent in other organisms are essentially lacking in Spirochetes. The largest Spirochete secondary carrier families consist of efflux systems. While both Bbu and Tpa exhibit an unusual degree of transporter diversity, major differences in specificity exist between these two organisms.

Borrelia burgdorferi Group↗
PubMed2000

Borrelia genomes in the year 2000.

All analyzed members of the spirochete genus Borrelia contain a linear chromosome about 910 kbp long. The complete sequence of the B. burgdorferi B31 genome predicts that its chromosome carries essentially all of this organism's housekeeping genes. In accordance with these bacterial species' obligatory parasitic lifestyle, its genes encode enzymes that are capable of only a minimal metabolism, in which all nucleotides, amino acids, fatty acids and enzyme cofactors must be scavenged from the host. In addition to the chromosome, all Borrelia isolates examined carry multiple linear and circular plasmids with lengths between 5 and 200 kbp. The plasmids, which account for over 600 kbp in isolate B31, carry very few genes with homology to genes outside of the Borrelia genus. But they do carry numerous predicted lipoprotein genes, many of which are have been shown to be or are expected to be outer surface proteins. Ten of the linear plasmids have strikingly low protein coding potential for bacterial DNA. These plasmids have enjoyed numerous past duplicative rearrangements, which have resulted in the presence of a substantial fraction of the DNA that appears to be currently undergoing mutational decay, presumably because it is no longer under selection for function.

Borrelia↗
PubMed2000

DNA exchange and insertional inactivation in spirochetes.

Spirochetes have complex life cycles and are associated with a number of diseases in humans and animals. Despite their significance as pathogens, spirochete genetics are in their early stages. However, gene inactivation has been achieved in Borrelia burgdorferi, Brachyspira hyodysenteriae, and Treponema denticola. Here, we review methods that have been used in spirochetes for gene inactivation and DNA exchange, with a primary focus on B. burgdorferi. We also describe factors influencing electrotransformation in B. burgdorferi. In summary, optimal transformation frequencies are obtained with log phase bacteria, large amounts of DNA (up to 50 microg per transformation), and high field strength (12.5-37.5 kV/cm). Infectious B. burgdorferi isolates transform with frequencies 100-fold lower than those found for high passage, non-infectious strains. Surface characteristics of the bacteria, which often correlate with infectivity, are among the obstacles to effective transformation by electroporation.

Animals↗
PubMed2000

[Investigations on Brachyspira--diagnostic and therapeutic strategies in swine dysentery].

The infectious agent of swine dysentery, Brachyspira (Br.) hyodysenteriae, seems to be widespread in German pig herds. Due to different reasons the eradication is increasingly difficult. Not only the success of therapeutic procedures but also the possibilities of diagnostics are unsatisfactory. Although only the bacteriological investigation of faeces or intestinal probes by culture techniques allows the typing of Brachyspira strains and the testing of drug resistance, however, the rate of false negative results is relatively high. In comparison with the cultural method an easy, prompt and cheap immunofluorescent test (IFT) resulted in a good sensitivity (90%). The higher rate of negative results by culture techniques can not be attributed to a lower specificity of the IFT, but to an insufficient transport of samples to the laboratory. The IFT therefore has to be considered as a valuable supplement to the cultural diagnostic of Br. hyodysenteriae. It is absolutely necessary to establish strategies in eradication of swine dysentery which result in pig breeding herds free of Br. hyodysenteriae. Only weaner pigs which are reliable free of this germ guarantee a fattening period sufficiently free of swine dysentery. The principles of different measures in effective eradication are described.

Animals↗
PubMed1997

[An investigation on peri-implant status in different types of dental implant].

Clinical, biochemical and microbiological methods were used to study the peri-implant status in different types of dental implant. Sixteen normal healthy adults with 12 one-stage implants and 22 two-stage implants were included in this study. Clinical parameters, proportion of subgingival spirochetes, detection rate of spirochetes were found to be significantly higher around one-stage implants than those around two-stage implants. No significant difference in gingival crevicular fluid flow, levels of aspartate aminotransferase and alkaline phosphatase was found between these two types. The bleeding index score in sites which harbored spirochetes was significantly higher than that in sites without spirochetes. The present data suggested that accumulation of plaque and existance of periodontal pathogens maybe related to peri-implant inflammation. This study suggests that plaque control and regular recall should be emphasized in implant maintenance.

Adult↗