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J F Anderson

Publications and source records attributed to J F Anderson.

At least 73 records · Page 4Linked to original sources

Comparison of whole-cell antibodies and an antigenic flagellar epitope of Borrelia burgdorferi in serologic tests for diagnosis of Lyme borreliosis.

A recombinant protein (p41-G) of an antigenic region of flagellin was used in a standard and amplified enzyme-linked immunosorbent assay (ELISA) to detect antibodies to Borrelia burgdorferi, the causative agent of Lyme borreliosis. Comparable sensitivities (88 to 94%) were noted when sera from 17 persons who had erythema migrans and antibodies to whole-cell B. burgdorferi were tested against the p41-G antigen. In tests of a second study group of 36 persons who had erythema migrans but no detectable antibodies to whole-cell B. burgdorferi, 3 (8%) were positive when the p41-G antigen was used. Assay specificity likewise increased when the p41-G fragment was included in an ELISA with human sera containing treponemal antibodies. Recombinant flagellar proteins of B. burgdorferi, such as the p41-G antigen, can be used in an ELISA and may help confirm Lyme borreliosis during early stages of infection and improve specificity.

Antibodies, Bacterial↗

Ribosomal DNA probe for differentiation of Babesia microti and B. gibsoni isolates.

The objective of this study was to determine whether different isolates of Babesia microti could be distinguished from morphologically similar isolates of B. gibsoni by using a ribosomal DNA (rDNA) probe. A Babesia-specific rDNA probe was obtained by polymerase chain reaction amplification of sequences from B. microti DNA using universal primers directed against highly conserved portions of the eukaryotic 16S-like rRNA gene. The chemiluminescent rDNA probe hybridized to Southern blots of restriction endonuclease-digested DNA preparations of different isolates of B. gibsoni from infected dogs and B. microti from infected humans and white-footed mice. Restriction fragment length polymorphisms served to differentiate these species. Although the hybridization patterns seen with DNAs from six B. microti isolates did not vary, those of the five B. gibsoni isolates did indicate genotypic variation. We concluded that isolates of B. microti and B. gibsoni can be differentiated on the basis of restriction fragment length polymorphism detected with a chemiluminescent rDNA probe.

Animals↗

Antibodies to Borrelia burgdorferi in rodents in the eastern and southern United States.

Serologic studies were conducted to determine whether white-footed mice (Peromyscus leucopus) and cotton mice (Peromyscus gossypinus) contained serum antibodies to Borrelia burgdorferi, the causative agent of Lyme borreliosis. Enzyme-linked immunosorbent assays detected antibodies to this spirochete in 35.7 and 27.3% of 56 P. leucopus and 535 P. gossypinus serum samples, respectively, collected in Connecticut, North Carolina, South Carolina, Georgia, Florida, Alabama, and Mississippi. Antibody titers ranged from 1:160 to greater than or equal to 1:40,960. On the basis of adsorption tests, the antibodies detected appeared to be specific to Borrelia spirochetes. Seropositive rodents in the eastern and southern United States, areas where human cases of Lyme borreliosis have been reported, indicate a widespread geographic distribution of B. burgdorferi or a closely related spirochete.

Animals↗

Effect of photoperiod on metabolic rate in a subtropical population of Drosophila melanogaster.

1. Descendents of a Florida, U.S.A. population of Drosophila melanogaster were reared under short (8 hr light: 16 hr dark) and long (16 hr light: 8 hr dark) photoperiods. 2. Flies reared under short photoperiods had higher rates of metabolism at 21 degrees C. 3. Because genetic background (iso-female line) affects metabolic rates, statistical control through analysis of covariance was necessary to isolate the effects of photoperiod on metabolic rates. 4. These results on a subtropical population of D. melanogaster are similar to those found on a temperate population of the same species.

Animals↗

Transfusion-transmitted babesiosis: a case report from a new endemic area.

The seventh documented case of babesiosis transmitted by transfusion is reported. Both the donor and the recipient are residents of Connecticut, where the presence of endemic babesiosis has only recently been established. As the range of Babesia microti, and its vector the Ixodes dammini tick, continues to expand, clinicians and blood bank directors should be aware that cases of transfusion-transmitted babesiosis may occur in newly endemic areas.

Animals↗

Babesia microti, human babesiosis, and Borrelia burgdorferi in Connecticut.

Babesia microti was isolated from a white-footed mouse (Peromyscus leucopus) that was captured in southeastern Connecticut in 1988, when the first human case of babesiosis acquired in Connecticut was recognized. To date, 13 cases of babesiosis have been reported in Connecticut, the largest number of human cases reported on the mainland United States. Two of nine patients quiried remembered a prior tick bite. Since Babesia parasites are known to be vectored only by ticks, we surmise that 12 of these infections were acquired via tick bites; 1 was obtained by blood transfusion (the patient was 46 years of age) from an endemically infected donor. The ages of the patients with tick-acquired babesiosis ranged from 61 to 95 years. Two patients died with active infections, and one patient died from chronic obstructive pulmonary disease soon after treatment with clindamycin and quinine. Indirect fluorescent-antibody titers of blood samples drawn at the time of hospitalization for 11 patients and at the time of active infection for 1 asymptomatic person ranged from 1:1,024 to 1:4,096. Five of eight patients with babesiosis also had significant immunoglobulin G or immunoglobulin M titers (1:640 to 1:5,120) to Borrelia burgdorferi. B. microti was isolated in Syrian hamsters inoculated with blood from 7 of 12 patients tested and was also isolated from mice captured in six towns. The peridomestic nature of the disease was demonstrated by isolating the parasite from white-footed mice captured in or near the yards of eight different patients. Of 59 mice tested, 27 were positive and 25 were coinfected with B. burgdorferi. The isolation of B. microti from a white-footed mouse captured in north-central Connecticut (West Hartford), away from the focus of human infections in southeastern Connecticut, suggests that this pathogen may spread into other areas where Ixodes dammini, the tick vector, becomes established.

Adult↗

Isolation and characterization of Borrelia burgdorferi from Illinois Ixodes dammini.

Ixodes dammini ticks from two northwestern Illinois sites were found to be infected with Borrelia burgdorferi at rates of 19 and 32%. B. burgdorferi isolates, one from each site, had protein and antigenic patterns similar to those of the B-31 strain. An indirect immunofluorescence method proved to be more sensitive than dark-field microscopy in detection of these spirochetes. A modified BSK medium containing rifampin was found to be more efficient for spirochete isolation than unsupplemented BSK medium.

Animals↗

Adsorption and biotin-streptavidin amplification in serologic tests for diagnosis of Lyme borreliosis.

Serum samples from persons with Lyme borreliosis, periodontitis, or acute necrotizing ulcerative gingivitis were analyzed by an enzyme-linked immunosorbent assay (ELISA) with and without adsorption and amplification procedures. When biotin and streptavidin reagents were used as an amplification procedure in ELISA without the use of commercially prepared sorbent (Treponema phagedenis biotype Reiter), sensitivity increased. Of the 85 serum samples collected from persons with erythema migrans but no detectable antibodies to Borrelia burgdorferi by standard ELISA, 17 (20%) were reactive after amplification. Adsorption of serum samples with a 1:10 dilution of T. phagedenis biotype Reiter sorbent used in conjunction with amplified ELISA also improved the sensitivity of this method. However, cross-reactivity could not be completely eliminated. An adsorbed-amplified ELISA may be helpful in the diagnosis of Lyme borreliosis in the laboratory, particularly during early weeks of infection, when antibodies to B. burgdorferi can be present at a low concentration.

Antibodies, Bacterial↗

Antibodies to Borrelia burgdorferi in deer and raccoons.

An enzyme-linked immunosorbent assay (ELISA) was developed to detect serum antibodies to Borrelia burgdorferi, the causative agent of Lyme borreliosis, in deer (Odocoileus virginianus) and raccoons (Procyon lotor). Blood samples were collected from these mammals in Connecticut, Maryland, North Carolina, Georgia and Florida. Seropositivity for deer was highest in Connecticut (56% of 353 sera) and Maryland (51% of 35 sera). Raccoons in Connecticut, Maryland, North Carolina, and Florida also had antibodies to B. burgdorferi, but prevalence of positive sera was highest in Maryland (79% of 14 samples). Based on adsorption tests, the immunoglobulins detected in these mammals were probably specific to B. burgdorferi. The ELISA was more sensitive than an indirect fluorescent antibody staining method and was more suitable for analyzing large numbers of serum samples.

Animals↗

Taxonomy of Borrelia spp.

An increasing number of phenotypically heterogeneous borrelia isolates have been obtained by culture. Genetic analysis of some of them suggest that a reorganisation in delineation of the different species within the genus Borrelia may be necessary. Specifically increasing numbers of variants phenotypically different from the American type strain of B. burgdorferi have been described. In this workshop experts have discussed phenotypic and genotypic characters for (a) differentiation of B. burgdorferi strains from other borrelia and from treponemes, (b) characterization of B. burgdorferi isolates at the subspecies level. Ultrastructure was discussed by K. Hovind-Hougen, antigen structure by B. Wilske and genotypic characters by G. Baranton, A. G. Barbour, R. C. Johnson and V. Preac-Mursic. J. F. Anderson discussed differences between strains isolated from a wide range of vectors and hosts in North America. The outcome of the workshop was that B. burgdorferi may comprise different genomic species which however share common epitopes recognized by certain monoclonal antibodies. At the subspecies level a broad heterogeneity was demonstrated using methods as restriction endonuclease analysis, hybridization with whole B. burgdorferi-DNA or specific probes as well as plasmid analysis. A serotyping system based on monoclonal antibody reactivity against the outer surface protein OspA was proposed. A comparison of the different typing methods is impaired by use of different strains for analysis. In the future a broad variety of phenotypically different and defined strains need to be analysed for genotypic clusters and later on reexamined for phenotypic characters. To accomplish this close cooperation of different research groups is necessary.

Animals↗

Epizootiology of Lyme borreliosis.

Borrelia burgdorferi is transmitted from animals to humans by ticks belonging primarily to the Ixodes ricinus complex. Transmission occurs during feeding, either by salivation, regurgitation, or by both processes. Two Eurasian (Ixodes ricinus and I. persulcatus) and three North American (I. dammini, I. scapularis and I. pacificus) species vector B. burgdorferi to humans. All ticks feed on three different host animals during their lives, and each species parasitizes a relatively large number of different host animals. For example, Ixodes ricinus is known to feed on more than 300 different kinds of mammals, birds, and reptiles. Borrelia burgdorferi has been isolated or detected in 24 different species of mammals or birds. Rodents belonging to the genera Peromyscus and Apodemus are important reservoirs in North America and Europe, respectively. Birds are a natural means of distributing infected ticks long distances during their migratory flights. Reptiles may not support the growth of borreliae. The B31 strain of B. burgdorferi is predominant in north-eastern United States. It is the only strain known to cause disease in humans, and the only one thus far isolated from rodents. In Europe, variants with distinctly different proteins from those found in the B31 strain also are infectious to humans, through they have not been identified with any specific clinical syndrome of Lyme borreliosis. Variants of the B31 strain have been isolated from lagomorphs in the United States.

Animals↗

Relationship of Borrelia burgdorferi to its arthropod vectors.

At the IV International Conference on Lyme Borreliosis, a workshop was held to identify the unique development of the Lyme disease spirochete, Borrelia burgdorferi, in its established and suspected arthropod vectors. The following is a summary of the panel's discussions of research aspects concerning relationship(s) of this borrelia to its vectors, and the mode(s) of its transmission to animal hosts.

Animals↗

Tick parasitism and antibodies to Borrelia burgdorferi in cats.

Ticks were removed from naturally infested cats, and serum samples from these cats were tested for antibodies to Borrelia burgdorferi. Twenty-two of 93 cats (23.7%) had one or more motile stages of Ixodes dammini attached. Of 2 larvae and 20 nymphs removed from cats, 1 larva and 2 nymphs were infected with B burgdorferi. Spirochetes were not found in tissues of 13 female and 4 male ticks. Ten of 71 serum samples analyzed by indirect fluorescent antibody staining or ELISA contained antibodies to this spirochete. Maximal antibody titers were 1:256 and 1:2,560, respectively. At titers greater than or equal to 1:160 in ELISA, seropositivity ranged from 8.8% (n = 34 sera tested from 34 cats) in May through July to 33.3% (n = 12 cats tested) during February through April. In clinical studies of 30 cats, there were nearly equal percentages of seropositive cats with limb or joint disorders not accompanied by fever, anorexia, or fatigue (5 of 21 cats) and cats with these signs of illness but lacking lameness (2 of 9 cats.)

Animals↗

Persistence of antibodies to Borrelia burgdorferi in dogs of New York and Connecticut.

Multiple blood samples were obtained from privately owned dogs living in tick-infested areas of New York (Westchester County) and Connecticut, where Lyme disease in human beings has been reported. Of the 175 dogs examined, 127 (72.6%) had limb/joint disorder, whereas the remaining 48 dogs were considered healthy. Results of analysis of 419 serum samples revealed IgM antibody to Borrelia burgdorferi in healthy and lame dogs during all seasons. Prevalence of seropositivity was significantly (P less than 0.01) greater, using a polyvalent ELISA (89.5%) than using a class-specific ELISA for IGM antibody (57.8%). Mean antibody titers obtained by use of polyvalent ELISA were likewise higher than IgM titers. Analysis of paired serum samples from dogs with limb/joint disorder indicated that 118 (92.9%) remained positive for IgM or IgG antibodies when retested weeks or months after initial testing. In 48 dogs without history of joint involvement or other signs of disease, 43 (89.6%) had antibody to B burgdorferi 2 or more times. Serotest results also revealed little or no change in antibody titer for lame dogs given antibiotics or for healthy dogs 2 or more months after initial sample collection.

Animals↗

Seasonal change in metabolic rate of Drosophila simulans.

1. Second-generation descendents of wild-caught female Drosophila simulans Sturtevant collected at different seasons from Gainesville, Florida, USA, were reared under a constant temperature and food level but with seasonally variable photoperiods. 2. Body weight and metabolic rate, after adjustment to a common body weight, were higher in descendents of flies collected in fall and winter. 3. Temperature sensitivity (Q10) of metabolic rate was also related to season: higher Q10 values were associated with seasons of increasing temperatures and lower Q10 values were associated with seasons of decreasing temperatures. 4. These metabolic characteristics may be adaptive in enhancing activity at lower temperatures and conserving energy at higher temperatures.

Animals↗

Infectious but nonpathogenic isolate of Borrelia burgdorferi.

We document for the first time an infectious but nonarthritogenic variant of Borrelia burgdorferi. Strain 25015, previously isolated from an Ixodes dammini larva collected in upstate New York, was infectious but failed to produce arthritis or carditis in laboratory rats and mice. By contrast, pathogenic strain N40 invariably caused arthritis. This nonarthritogenic variant, with proteins with molecular weights different from those of the standard B31 strain, was frequently isolated from normal joint tissues of experimentally infected rats. Outer surface proteins A and B of strain 25015 have molecular weights of about 32,500 and 35,500, respectively, in contrast to molecular weights of approximately 31,000 and 34,000, respectively, for outer surface proteins A and B of strains B31 and N40. A prominent low-molecular-weight protein of about 23,500 also characterizes strain 25015. Test animals infected for 30 to 60 days had relatively high antibody titers (greater than or equal to 1:1,280). The nonarthritogenic variant will be useful, along with pathogenic strains, in providing comparative insight into the pathogenesis of Lyme borreliosis. Homologous immunoblotting of sera from rats and mice inoculated with both the arthritogenic and nonarthritogenic strains revealed antibody reactivities to proteins of B. burgdorferi different from those revealed in the heterologous tests.

Animals↗

Canine ehrlichiosis in Connecticut.

The first case of canine ehrlichiosis in Connecticut is reported. A female Brittany spaniel from Milford presented with lethargy, anorexia, fever, petechiae, splenomegaly, thrombocytopenia, anemia, elevated serum alkaline phosphatase, lymphopenia, and hypoalbuminemia. Serologic analysis revealed antibodies to Ehrlichia canis (titer, 1:2,560). This documents a more northern geographic distribution in the United States for this infectious agent than had previously been suspected.

Animals↗