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Biomedical subjects

J G Tully

Publications and source records attributed to J G Tully.

At least 127 records · Page 7Linked to original sources
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Spiroplasma species share common DNA sequences among their viruses, plasmids and genomes.

Alkaline-Southern-blot analyses showed that a spiroplasma plasmid, pRA1, obtained from Spiroplasma citri (Maroc-R8A2), contained DNA sequences that were homologous to spiroplasma type 3 viruses (SV3) obtained from S. citri (Maroc-R8A2), S. citri (608) and S. mirum (SMCA). In addition, pRA1 and SV3(608) DNA shared common, but not necessarily related, sequences with extrachromosomal DNA derived from 11 Spiroplasma species or strains. Furthermore, SV3(608) had DNA homology with the chromosome from 6 distinct spiroplasmas but not with chromosomal DNA from eight other Spiroplasma species or strains. The biological function of these common sequences is unknown.

Bacteriophages↗
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Genetic and serologic relatedness between Mycoplasma fermentans strains and a mycoplasma recently identified in tissues of AIDS and non-AIDS patients.

A mycoplasma previously identified in the tissues of both AIDS and non-AIDS patients dying of an acute fatal disease was earlier shown to share some biologic and genetic properties with a strain of Mycoplasma fermentans, an organism occurring infrequently in the human lower urogenital tract. More extensive genetic and serologic comparisons using DNA/DNA hybridization, DNA base composition (guanine + cytosine), restriction endonuclease DNA analysis, cellular protein patterns and metabolism inhibition serologic procedures confirm that the organism previously designated as "Mycoplasma incognitus" (Mi) is indeed very closely related to strains of M. fermentans. While the genetic and serologic features observed among the newly isolated mycoplasma and two M. fermentans strains suggest a species relationship, it now seems useful to re-examine the biological activities of other freshly isolated M. fermentans strains from man.

Acquired Immunodeficiency Syndrome↗
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Localization and persistence of spiroplasmas in an experimental brain infection in suckling rats.

The GT-48 strain of Spiroplasma mirum was employed in an experimental brain infection in 1-day old suckling rats in order to define the localization and persistence of organisms in brain and spleen and to evaluate the responses of three distinct genetic lines of rats. Rat pups inoculated intracerebrally with 30-300 organisms exhibited peak infections at 15-20 days post-inoculation, while challenge levels of 3-30 organisms showed some persistent infections for as long as 60 days. The responses of three genetic lines of rats to the experimental spiroplasma infection did not differ significantly over a 60-day follow-up period. The acute-phase infection in suckling rats showed a rapidly developing and widespread dissemination of organisms to all major areas of the brain.

Acute Disease↗
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Guanine-plus-cytosine content, hybridization percentages, and EcoRI restriction enzyme profiles of spiroplasmal DNA.

The guanine-plus-cytosine (G + C) content of spiroplasmal DNA was calculated from the melting temperature determined spectrophotometrically and the buoyant density determined by equilibrium density gradient centrifugation in CsCl. Only two ranges of G + C values were found: 25-27 mol% and 29-32 mol%. The DNA of the following spiroplasmas has 25-27 mol% G + C: Spiroplasma citri (serogroup I-1); the spiroplasmas pathogenic to the honeybee (KC3, BC3, and B63; serogroup I-2); the corn stunt strain (E275; serogroup I-3); the tick strain 277F (serogroup I-4); the drosophila strain (serogroup II); and one group of flower spiroplasmas (serogroup III). The DNA of a second group of flower spiroplasmas (serogroup IV) and the SMCA strain (serogroup V) has a G + C content of 29-31 mol/. The classification of flower spiroplasmas into two groups on the basis of G + C content agrees well with the groupings based on serologic and protein analysis. Spiroplasmas isolated from honeybees in Morocco (B13) or froghoppers in Corsica (L89) have 29-31 mol% G + C, a value that corroborates the relatedness of these strains and the flower spiroplasmas of serogroup IV found by serologic analysis. Reannealing experiments between the vivo-labeled DNA of S. citri and unlabeled DNA of other spiroplasmas gave the following percentages of hybridization: 64% with honeybee spiroplasma DNA, 49% with corn stunt spiroplasma DNA, and 19% with tick spiroplasma 277F DNA; no significant hybridization was observed with DNA of any other spiroplasma. The taxonomic position of the tick spiroplasma 277F within serogroup I was confirmed by hybridization experiments involving [3H]DNA of this strain. The value of polyacrylamide gel analysis of DNA fragments produced by the action of EcoRI restriction enzyme on DNAs from various spiroplasmas is also discussed.

Animals↗
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Characterization of spiroplasmas by serology.

Five major serologic groups of spiroplasmas have been distinguished on the basis of serology (as determined in a test of deformation and metabolism inhibition), guanine-plus-cytosine content of DNA, and DNA-DNA hybridization. group I includes strains of Spiroplasma citri that form a classical subgroup (serovar) complex of four serologically homogeneous serovars that cross-react with each other at varying levels. The four other serogroups do not cross-react with each other or with members of the group I S. citri complex. Group II consists of the sex ratio spiroplasma from Drosophila species. Group III contains spiroplasmas isolated from flowers of magnolia and tulip trees. Group IV consists of strains of spiroplasmas recovered from insects and flowers. The tick-derived spiroplasmas SMCA and TP-2 compose group V.

Cytosine↗
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Polyacrylamide gel analysis of spiroplasmas proteins and its contribution to the taxonomy of spiroplasmas.

Representative strains of the known groups and serogroups of spiroplasmas have been compared on the basis of the results of one- and two-dimensional protein analysis on polyacrylamide gels. Each of the four subgroups of the Spiroplasma citri complex (S. citri and honeybee, corn stunt, and 277F spiroplasmas) has characteristic protein profiles and maps. Spiroplasma G1 isolated from flowers has a protein profile closely related to that of the honeybee spiroplasmas (KC3, BC3, AS576, B1707, B88, and B63). The flower spiroplasmas fall into two groups on the basis of the mole percentage (mol%) of guanine plus cytosine (G + C) of their deoxyribonucleic acid (DNA) 26 and 30 mol %, respectively) and their serologic properties. The three flower spiroplasmas (OBMG, BNR1, and 23-6) with 26 mol % of G + C have the same basic protein pattern. Although some of the flower spiroplasmas with 30 mol % of G + C have closely related protein patterns, others have more distant profiles. Spiroplasmas B13 and L89, isolated from honeybees and froghoppers, respectively, had DNA with 30 mol % of G + C and could be included with other flower spiroplasmas with similar DNA base composition on the basis of their protein profiles and maps. Individual proteins separated by two-dimensional analysis on polyacrylamide gels have been used for the production of monospecific immunoglobulins, which are useful in taxonomic studies.

Animals↗
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Mycoplasmas: sophisticated, reemerging, and burdened by their notoriety.

Mycoplasmas are most unusual self-replicating bacteria, possessing very small genomes, lacking cell wall components, requiring cholesterol for membrane function and growth, using UGA codon for tryptophan, passing through "bacterial-retaining" filters, and displaying genetic economy that requires a strict dependence on the host for nutrients and refuge. In addition, many of the mycoplasmas pathogenic for humans and animals possess extraordinary specialized tip organelles that mediate their intimate interaction with eucaryotic cells. This host-adapted survival is achieved through surface parasitism of target cells, acquisition of essential biosynthetic precursors, and in some cases, subsequent entry and survival intracellularly. Misconceptions concerning the role of mycoplasmas in disease pathogenesis can be directly attributed to their biological subtleties and to fundamental deficits in understanding their virulence capabilities. In this review, we highlight the biology and pathogenesis of these procaryotes and provide new evidence that may lead to increased appreciation of their role as human pathogens.

AIDS-Related Opportunistic Infections↗
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Paraplegia, syringomyelia tarda and neuropathic arthrosis of the shoulder: a triad.

A casually related triad of syringomyelia tarda, postparaplegia with secondary neuropathic arthrosis of the shoulder has been presented. The development of neuropathic arthrosis of the shoulder has been presented. The development of neuropathic arthrosis of the shoulder in 2 of our paraplegic patients prompted us to look for a correlation and/or a common etiology. Paraplegia secondary to spinal cord injury could be causative or at least an associated factor in a delayed proximal syringomyelia. It is the syringomyelia which can lead to the neuropathic arthrosis in the upper extremity, mainly, in the shoulder. There is an interesting pathological association of paraplegia and syringomyelia with neuropathic arthrosis. Earlier awareness of any neurological changes in the upper extremity of the paraplegic patient could point to recognition of syringomyelic process and portend a tendency toward neuropathic arthrosis of the shoulder. This would require a high index of suspicion, and subsequently a preventative, protective orthopedic approach to minimize the usual functional deformity that occurs when this neuropathy involves the shoulder.

Adult↗
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Spiroplasmas of Group I: the Spiroplasma citri cluster.

We propose that Group I spiroplasmas be subdivided into seven, rather than four, subgroups. The seven subgroups showed remarkable homogeneity when several representative strains were compared. Hybridization reactions between DNAs of representative strains within subgroups were generally at least 90 percent, and usually at least 80 percent co-migrating cell proteins were found. In addition, when plasmid DNA was excluded, profiles of restricted DNA among strains within subgroups were very similar. In contrast, comparisons between Group I subgroups showed substantial heterogeneity. This heterogeneity was indicated by DNA-DNA hybridization reactions as low as 10-20 percent and only 10-15 percent co-migrating cell proteins. Spiroplasma citri (subgroup I-1), the honeybee spiroplasma (subgroup I-2), and the corn stunt spiroplasma (subgroup I-3) are all pathogenic organisms with more or less limited host ranges. Strains of these three subgroups have been repeatedly isolated from affected hosts. Since strains of subgroups I-2 and I-3 can be clearly differentiated from other Group I subgroups and all other spiroplasmas, the DNA-DNA hybridization reactions of the subgroups do not exceed 70 percent, and because they are important pathogens, we propose (subject to completion of standard requirements for species descriptions) that they be recognized as new species of the genus Spiroplasma.

Animals↗
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Spiroplasma apis, a new species from the honey-bee Apis mellifera.

Two spiroplasma strains (B31 and B39) recovered from diseased honey-bees (Apis mellifera) in southwestern France were similar in biochemical, serological and pathological properties. The organisms grew at 30 degrees C, required cholesterol for growth, fermented glucose, catabolized arginine and produced a film and spot reaction. The two spiroplasmas were serologically indistinguishable but were related to serogroup IV spiroplasmas, which had been previously isolated from flower surfaces and from insects. The isolates were distinct from the three previously established species of Spiroplasma and from other presently known serogroups. The G + C content of the DNA from strain B31 was 30 +/- 1 mol %. Both B31 and B39 strains were associated with a lethal infection ("May disease") of the honey-bee. On the basis of the characterization presented here, it is proposed that these spiroplasmal pathogens of bees and allied strains be classified as a new species, Spiroplasma apis, the type strain of which is B31 (ATCC 33834).

Animals↗
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Mycoplasma hominis- tissue cell interactions: a review with new observations on phenotypic and genotypic properties.

Strains of Mycoplasma hominis isolated from different tissues of patients with a variety of disease processes and from cell culture substrates show marked phenotypic and genotypic heterogeneity, as determined by their antigenic and isozyme properties and by [3H]DNA-DNA hybridization and DNA cleavage pattern analyses. Strains isolated from the same tissues (blood of postpartum patients or human urogenital tract or cell culture substrates) have very high genomic homology and form clusters of similar strains. Clusters of strains that colonize similar specialized urogenital tissues may initiate diseases that reflect damage to the particular tissue colonized. Antigenic markers such as those for attachment components for different strain clusters may help determine the role, if any, played by strain differences in the etiology of a family of urogenital diseases.

Adhesiveness↗
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Characterization and taxonomic status of tick spiroplasmas: a review.

Three serologically distinct groups of spiroplasmas have been recovered from ticks. Spiroplasma mirum strains (from rabbit ticks, Haemaphysalis leporispalustris) and Y32 group (VI) spiroplasmas (from Ixodes pacificus) are the only spiroplasmas to have a clear association with these arthropods. Group (VI) spiroplasmas are distinguished by an unusual nonhelical morphology and their capacity to hemadsorb guinea pig erythrocytes. S. mirum strains are unique in their ability to induce cataracts or lethal brain infections in a number of young vertebrates and in their virulence for the chick embryo. The 277F spiroplasma, while initially recovered from a pool of rabbit ticks (H. leporispalustris), is related by certain serological and genetic properties to spiroplasmas in the S. citri complex (serogroup I). These relationships suggest that the 277F spiroplasma may not be a natural inhabitant of the rabbit tick.

Animals↗
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The Emmy Klieneberger-Nobel Award lecture. Reflections on recovery of some fastidious mollicutes with implications of the changing host patterns of these organisms.

Major advances have occurred the past few years in the cultivation of a number of new, fastidious mollicutes--events which can be traced directly to successful efforts to develop culture media for the expanding group of helical mollicutes (spiroplasmas) inhabiting plants and arthropods. A description of cultivation techniques successful in primary isolation of three unusual mollicutes, representing new mycoplasmas from man and animals and a new spiroplasma from ticks, emphasizes some important factors in recovery of wall-less prokaryotes with special cultural requirements. Vigorous efforts to understand the distribution of spiroplasmas in plant and insect hosts also led to the cultivation of new, non-helical mollicutes. Preliminary characterization of a number of these new agents offers strong evidence for a unique and distinct Acholeplasma and Mycoplasma flora of both plants and insects.

Acholeplasma↗
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New laboratory techniques for isolation of Mycoplasma pneumoniae.

The SP-4 culture medium, developed originally for newly isolated plant and insect mycoplasmas (spiroplasmas), has markedly improved the recovery of Mycoplasma pneumoniae from human clinical materials. This medium, in combination with a direct fluorescent antibody test, can enhance the recovery and identification of the organism by 30-40 percent over conventional culture procedures. Although these modifications are a clear improvement in diagnostic techniques for M. pneumoniae, the time required for growth and identification of the agent is still a major disadvantage for rapid clinical diagnosis. Thus, there remains a critical need for techniques that can specifically identify the major antigens (or other components) of the organism within the first week of the infection.

Agar↗
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Interspecies and intraspecies DNA homology among established species of Acholeplasma: a review.

Radiolabeled DNA probes prepared in vitro by the nick translation method were used to determine the nucleotide sequence homology among the eight established and one unclassified species of Acholeplasma. Very little DNA homology (2 to 21 percent) was found among these nine distinct species and the heteroduplexes showed at least 15 percent mismatching as determined by thermal elution endpoints. The data obtained by hybridization analyses paralleled the results obtained by the growth inhibition and epi-immunofluorescence serologic procedures. The small amount of nucleotide sequence homology among the nine distinct species indicate that the Acholeplasma species are quite distinct and unrelated to each other genomically, findings which should provide useful insight on the molecular biology and evolutionary pathways of these organisms. Labeled 3H-DNA probes to five strains of either A. laidlawii or A. axanthum hybridized to a varying degree to excess amounts of unlabeled DNAs from 12 strains of A. laidlawii and six strains of A. axanthum, respectively. Nucleic acid hybridization analyses showed a wide variation (48 to 100 percent) in DNA homologies among different strains of the two species. The results demonstrate that strains of A. laidlawii and/or A. axanthum isolated from diverse hosts and habitats (birds, rodents, cats, swine, sheep, cattle, horses, goats, primates, and plants) exhibit extensive genotypic variations. 3H-DNA-DNA hybridization procedures were found to be extremely useful in establishing or confirming the existence of distinct species within the genus Acholeplasma.

Acholeplasma↗