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At least 19 recordsLinked to original sources
PubMed1992

Isolation of Borrelia burgdorferi (Spirochaetales: Spirochaetaceae) from Ixodes scapularis and Dermacentor albipictus ticks (Acari: Ixodidae) in Oklahoma.

Borrelia burgdorferi was isolated from Ixodes scapularis Say and Dermacentor albipictus Packard that were removed as partially fed adults from white-tailed deer, Odocoileus virginianus Zimmermann, in Oklahoma. Isolation in media was accomplished only after homogenates of pooled field-collected ticks were inoculated into laboratory-reared Peromyscus leucopus and reisolated from the urinary bladder into BSK II media. Both isolates were confirmed by western blot analysis and reactivity with monoclonal antibody H5332. These are the first reported isolates of B. burgdorferi from Oklahoma from these two tick species and are the first isolates from ticks from the south-central United States that were infective for laboratory-reared P. leucopus.

Animals↗
PubMed1992

Attempted transmission of Borrelia burgdorferi (Spirochaetales: Spirochaetaceae) (JDI strain) by Ixodes scapularis (Acari: Ixodidae), Dermacentor variabilis, and Amblyomma americanum.

Laboratory-reared Ixodes scapularis Say, Amblyomma americanum (L.), and Dermacentor variabilis (Say) were fed on New Zealand white rabbits experimentally infected with Borrelia burgdorferi (JDI strain). At repletion, spirochetes could be detected by dark-field microscopy only in I. scapularis. Acquisition rates were 18 and 21%. When previously exposed nymphs of each species were fed on susceptible rabbits, I. scapularis was the only tick of the three species that transmitted B. burgdorferi. When a single rabbit was experimentally infected with B. burgdorferi and infested at 7-d intervals with I. scapularis, A. americanum, D. variabilis, and a second time with I. scapularis, B. burgdorferi was detected again only in cultures from the two groups of I. scapularis. When molted nymphs from each tick species were allowed to feed on susceptible rabbits, spirochetes again were isolated only at necropsy from the rabbits on which the two groups of I. scapularis fed.

Animals↗
PubMed1992

Cell wall-less, free-living spirochetes in Antarctica.

The phylogeny of an Antarctic, cell wall-less, bacterial strain was determined by sequencing PCR amplified 16S rDNA, and comparison of the sequence with other bacterial 16S rRNA sequences available in databanks. Although the strain was phenotypically very similar to members of the genus Anaeroplasma, phylogenetic analyses showed it was a member of the order Spirochaetales. Until now, the order was one of the few bacterial orders in which phylogeny was reflected in a uniform morphology of its members. The viability of wall-less cells in cultures of spirochetes and spirochetal infective material warrants reinvestigation.

Antarctic Regions↗
PubMed1991

Borrelia burgdorferi: another cause of foodborne illness?

Borrelia burgdorferi was identified as the etiological agent of Lyme disease in 1982. This Gram-negative spirochete is classified in the order Spirochaetales and the family Spirochaetaceae. The pathogen is fastidious, microaerophilic, mesophilic and metabolises glucose through the Embden-Meyerhof pathway. A generation time of 11 to 12 h at 37 degrees C in Barbour-Stoenner-Kelly medium has been reported. Lyme disease, named after Lyme in Connecticut, is distributed globally. It is the most commonly reported vector-borne disease in the United States, where the incidence is highest in the eastern and midwestern states. Since establishment of national surveillance in 1982, there has been a nine-fold increase in the number of cases reported to the U.S. Centers for Disease Control. The deer tick of the genus Ixodes is the primary vector of Lyme borreliosis. The tick may become infected with B. burgdorferi, by feeding on an infected host, at any point in its 2-year life cycle which involves larval, nymphal and adult stages. The infection rate in deer ticks may be as high as 40% in endemic areas. The primary vertebrate reservoirs for Ixodes are the white-footed mouse (Peromyscus leucopus) and the white-tailed deer (Odocopileus virginianus). Dairy cattle and other food animals can be infected with B. burgdorferi and hence some raw foods of animal origin might be contaminated with the pathogen. Recent findings indicate that the pathogen may be transmitted orally to laboratory animals, without an arthropod vector. Thus, the possibility exists that Lyme disease can be a food infection. In humans, the symptoms of Lyme disease, which manifest themselves days to years after the onset of infection, may involve the skin, cardiac, nervous and/or muscular systems, and so misdiagnosis can occur.

Animals↗
PubMed1990

Cloning of genes required for amino acid biosynthesis from Leptospira interrogans serovar icterohaemorrhagiae.

Leptospira interrogans belongs to a large family of important pathogens, which is part of the order Spirochaetales, a distinct group of eubacteria. In order to obtain a better understanding of the genetic organization of this species, we have constructed a DNA library of the serovar icterohaemorrhagiae, using the Escherichia coli vector pUC13. We have isolated Leptospira DNA fragments containing the genetic information required to complement strains of E. coli with defects in proline and leucine biosynthesis. While a 3.9 kb fragment which complemented proA also complemented proB, a 15 kb fragment complementing leuB could not complement other leu mutations. The L. interrogans origin of the cloned DNA fragments was confirmed by DNA-DNA hybridization. The hydridization was specific to the pathogenic species and was not seen with the saprophytic species L. biflexa.

Amino Acids↗
PubMed1989

Unusual in vitro formation of cyst-like structures associated with human intestinal spirochaetosis.

Spirochaetes were isolated from rectal biopsies of three patients and successfully cultured. Enzymatic reactions and electron microscopy revealed spirochaetes resembling Brachyspira aalborgi. Examination of ultrathin sections of centrifugates of cultured spirochaetes yielded unusual cyst-like structures with an outer double membrane containing spirochaetes in different developmental stages. The protoplasmic cylinders seemed to originate from a large electron-dense focus in the cyst-like structures. The axial fibrils occurred as loosely distributed solitary structures in the cyst-like structures. Cysts were not found in the biopsy tissue. The encystment of the spirochaetes could be related to their protection, multiplication, spread and transmission.

Colitis↗
PubMed1990

Morphological heterogeneity among spirochetes isolated from cases of swine dysentery.

Pathogenic and non-pathogenic spirochetes isolated from the intestines of pigs were examined by electron microscopy using the negative staining and ultrathin sectioning techniques. Morphological differences were observed among cells of different strains. The cells differed in length as well as in width and in the number of flagella inserted at each end. In addition, the cells from different strains also varied in their resistance to the action of the detergents, Teepol and sodium deoxycholate. Three of the strains studied contained weakly haemolytic spirochetes, two of which differed markedly in their morphology from the cells of the other strains. These spirochetes had fewer flagella inserted at each end than those from other isolates and showed a distinct lattice-like substructure covering the ends of the cells. The spirochetes examined were found to be morphologically more similar to those of the genus Borrelia than to those of the genus Treponema but were clearly different from the cells of both of these genera. The taxonomic implications of the observations are discussed in brief.

Animals↗
PubMed1990

Intestinal spirochaetes in a Gulf Arab population.

Spirochaetal bacteria were isolated from the faeces of 11.4% of 1000 hospital patients and 26.7% of 292 healthy local nationals in the Muscat area of the Sultanate of Oman. A case-control study of patient records showed the isolation of the spirochaete to be associated with Omani nationality, age in excess of 2 years and attendance at self-referral health-care facilities. No association was found with symptomatic intestinal disease or microscopic abnormalities of the stool.

Adolescent↗
PubMed1990

[Intestinal spirochetosis in HIV infection: prevalence, isolation and morphology of spirochetes].

The prevalence of intestinal spirochaetosis was investigated in 39 HIV-positive homosexual males (mean age 39 [24-65] years) in different stages of HIV infection (3 with the lymphadenopathy syndrome, 8 with AIDS-related complex and 28 with AIDS). Biopsies for cultural and histological demonstration of spirochaetes were obtained during routine ileoscopies. At the time of examination 35 of the 39 patients had intestinal symptoms. 27 patients had had no previous antimicrobial treatment. In 12 of the 27 previously untreated patients with intestinal symptoms spirochaetes were demonstrated, to different extent, from the terminal ileum to the rectum, while the treated group of eight and the control group of four were negative. There were no significant inflammatory changes histologically. Treatment with metronidazole in most cases improved symptoms. In their ultrastructure the microorganisms showed several complete convolutions, cone-shaped cell endings, cell length of 4-18 microns, cell diameter of 0.21-0.35 microns and five subterminal flagella. Morphological considerations favour the inclusion of these microorganisms in the genus Treponema rather than Brachyspira.

AIDS-Related Complex↗
PubMedDate not supplied

Spirochete-like organisms in the human gastrointestinal tract.

Spirochete-like organisms were first detected in human feces in 1884. In the century since that observation an appreciable amount of epidemiologic and morphologic information has been published; nevertheless, it is not known how many species of cultivable human intestinal spirochetes exist, nor is the role of these organisms in health and disease known. Recent advances in microbiologic techniques, coupled with the recognition that the rate of carriage of such spirochetes in certain populations is approximately 30%-40%, should provide the impetus for careful scientific study of these organisms and of their importance-if any-to human health.

Diarrhea↗
PubMedDate not supplied

Isolation techniques for spirochetes and their sensitivity to antibiotics in vitro and in vivo.

Leptospira interrogans can be cultured from blood and cerebrospinal fluid during the first week of leptospirosis and from urine thereafter. Studies of in vitro sensitivity indicate that these organisms are sensitive to most antibiotics. Tetracycline and penicillin G are most often used clinically, although laboratory studies suggest that the bactericidal activity of penicillin G may be inadequate. Treponema pallidum cannot be satisfactorily cultured. It is identified by dark-field microscopy. Studies of in vivo sensitivity show that penicillin G is highly active against the syphilis pathogen. Since syphilis and gonorrhea may occur simultaneously, ceftriaxone, which is as active as penicillin G against T. pallidum but is also active against penicillinase-producing gonococci, is a logical choice for therapy. Borrelia burgdorferi has been cultured from the blood, cerebrospinal fluid, and skin of patients with Lyme disease. In vitro studies have shown tetracycline and erythromycin to be effective against B. burgdorferi and penicillin G to be less so, although all are commonly used clinically. Ceftriaxone has also proven to be highly effective in laboratory studies and for clinical treatment.

Animals↗
PubMed1977

Intestinal Tyzzer's disease and spirochetosis in a guinea pig.

Tyzzer's disease (bacillus pilirformis infection) was diagnosed in young guinea pig killed because of diarrhea and poor condition. There was necrosis and inflammation of the colon, cecum and ileum. Typical B. piliformis were in intestinal epithelial cells. Spirochetes were in large numbers in intestinal crypts and were often adjacent to the intracellular B. piliformis. Extracellular B. piliformis occasionally were surrounded by spirochetes.

Animals↗
PubMed1989

Etiologic studies on late-term swine abortions.

One hundred thirty-eight swine abortions were studied in detail in an effort to identify an etiologic agent. A viral agent was implicated in 7 cases. Bacteria were isolated in less than half of the examined cases: however, in 61% of the cases, motile, filamentous organisms were observed in tissues and fluids. Although swine sera from farms experiencing reproductive problems had a high reactor rate to Leptospira bratislava antigen, electron microscopy of the observed organism revealed a wall-free prokaryote morphologically typical of the class Mollicutes.

Abortion, Veterinary↗
PubMed1976

Influence of medication on development of serum antibody to swine dysentery as detected with indirect fluorescent antibody method.

Serums from 119 swine exposed to swine dysentery inoculum, and medicated with various drugs, were tested for antibodies to the large spirochete, using the indirect fluorescent antibody test, and were compared in tests with known positive serums from 18 nonmedicated swine which had recovered naturally. An inverse relationship existed between the efficacy of the drug and the serum antibody titer (highest dilution of the serum producing immunofluorescence of large spirochetes). The more efficacious drugs or doses resulted in lesser development of serum antibody. Diarrhea usually seemed necessary for the development of serum antibody. With the less efficacious drugs, there were more days of diarrhea. Some swine had diarrhea but did not develop an antibody titer, and a few swine had a titer but did not develop diarrhea. Swine which developed a titer were more immune against reexposure with infective inoculum. The medicaments, especially those given at higher concentrations, seemed to resolve the diarrhea or prevent the development of diarrhea, occurrences which were necessary for the development of immunity.

Animals↗