PubMed Health⌕ Search

Biomedical subjects

M F Barile

Publications and source records attributed to M F Barile.

At least 55 records · Page 3Linked to original sources
PubMed1987

Animal models of Mycoplasma genitalium urogenital infection.

Male and female animals were inoculated urogenitally with Mycoplasma genitalium, recovered originally from men with nongonococcal urethritis. Mice, hamsters and male rhesus monkeys (Macaca mulatta) were resistant. Male cynomolgus monkeys (Macaca fascicularis) were not as sensitive as male chimpanzees (Pan troglodytes): 9 of 11 developed an obvious genital tract infection, some shedding organisms for more than 18 weeks. M. genitalium was recovered from the blood of two of them when large numbers of organisms were in the urethra. Most of the chimpanzees colonized with the organisms had increased numbers of polymorphonuclear leukocytes in the genital tract and developed a fourfold or greater antibody response. Female squirrel monkeys (Saimiri sciureus) and female tamarins (Saguinus mystar) exhibited low-level genital tract infections following intravaginal inoculation, whereas marmosets (Callithrix jacchus) and chimpanzees developed prolonged infections after similar inoculation; thus, female chimpanzees shed organisms for 12 to 15 weeks. Marmosets and grivet monkeys (Cercopithecus aethiops) developed salpingitis with antibody responses after intraoviduct inoculation, and baboons (Papio anubis) developed parametritis after intracervical inoculation. The results offer substantial evidence for the pathogenicity of M. genitalium for the urogenital tract of subhuman primates, and suggest that the microorganism may have a role in human genital tract infections.

Animals↗
PubMed1986

The beta-subunit of the F1F0-ATPase is conserved in mycoplasmas.

Monospecific polyclonal antibodies that were generated against the beta-subunit of Escherichia coli ATPase (F1Fo) cross-reacted with a protein present in the cells of several Mycoplasma and Acholeplasma species. In Mycoplasma gallisepticum, the reactive protein was found almost exclusively in the cell membrane. This protein had an apparent molecular mass of approximately 52 kDa and could not be released from the membranes by repeated washings with either low or high salt solutions in the presence or absence of EDTA. The reactive protein was found to be catalytically active, exhibiting up to 44% of the total membrane-bound ATPase activity. We suggest that mycoplasmas possess a F1Fo-ATPase which undergoes structural modification(s) allowing its integration into the membrane.

Animals↗
PubMed1986

Urogenital challenge of primate species with Mycoplasma genitalium and characteristics of infection induced in chimpanzees.

Eighteen male and eight female primates, representing five subhuman species, were inoculated urogenitally with Mycoplasma genitalium, a microorganism recovered from men with nongonococcal urethritis. Male rhesus (Macaca mulatta) and cynomolgus (Macaca fascicularis) monkeys apparently were resistant. Female squirrel monkeys (Saimiri sciureus) and female tamarins (Saguinus mystax) exhibited low-level, genital-tract infections. Male chimpanzees (Pan troglodytes) developed an obvious genital-tract infection, with some shedding organisms for 21 weeks. M. genitalium was recovered from the blood of two of the male chimpanzees, usually when large numbers of organisms were in the urethra. Female chimpanzees generally shed organisms for 12-15 weeks. Most chimpanzees colonized with the organism exhibited increased numbers of polymorphonuclear leukocytes in the genital tract and developed a significant antibody response. The results offer substantial evidence for the pathogenicity of M. genitalium for the urogenital tract of higher primates and suggest the microorganism may have a role in human genital-tract infections.

Animals↗
PubMed1986

Mycoplasma pneumoniae attachment to glutaraldehyde-treated human WiDr cell cultures.

Attachment of Mycoplasma pneumoniae to host cells initiates disease, and the attachment components may represent important protective immunogens for preventing disease. We have studied the mechanisms of attachment using in vitro cell culture systems and selected pathogenic and nonpathogenic strains of M. pneumoniae. Attachment of the pathogenic strains M129 and PI-1428 was several fold greater than attachment of the nonpathogenic strain, and attachment of strains M129 and PI-1428 was reduced by 21 to 63% when human WiDr cell monolayers were exposed to neuraminidase, supporting the concept that M. pneumoniae attaches to mammalian cells by a neuraminidase-sensitive glycoconjugate. While attachment of the two pathogenic strains was markedly reduced by treating the WiDr cells with glutaraldehyde, glutaraldehyde treatment produced minimal effects on the attachment of the nonpathogenic strain B176. Glutaraldehyde treatment also altered the temperature dependence of attachment by the pathogenic strains. Because glutaraldehyde-treated WiDr cell monolayers showed little difference in attachment between pathogenic and nonpathogenic strains, glutaraldehyde-treated cells are not appropriate cell substrates for studying M. pneumoniae attachment mechanisms or identifying immunogens for vaccine development.

Aldehydes↗
PubMed1985

Nucleic acid relationships among the anaerobic mycoplasmas.

The genetic relatedness between twelve selected strains among four distinct serovars of anaerobic mycoplasmas was studied using [3H]DNA-DNA hybridization, and the results were compared with data obtained from biochemical and serological tests. Radiolabelled DNA probes were prepared from five strains representing four serovars. Based on the homology results, the anaerobic mycoplasmas can be divided into five distinct groups representing five distinct species and two distinct genera. There are two species in the Anaeroplasma bactoclasticum serovar 1 group represented by strains JR and A-2, one species in serovar 2, one species in A. abactoclasticum serovar 3 and one among the unclassified serovar 4 anaerobic mycoplasmas. The probe to nonsterol-requiring strain 161 of serovar 4 showed no homology with any of the established nonsterol-requiring Acholeplasma species DNAs, or with Mycoplasma hominis DNA, or with avian DNA which served as a negative control. There was good correlation between the phenotypic and genotypic properties of the five distinct anaerobic mycoplasma species but the results indicate that phenotypic properties are not always adequate for speciation of the anaerobic mycoplasmas.

Base Composition↗
PubMed1985

Survey of immunoglobulin A protease activity among selected species of Ureaplasma and Mycoplasma: specificity for host immunoglobulin A.

Because immunoglobulin A (IgA) is the predominant immunoglobulin at mucosal surfaces, IgA proteases produced by pathogenic bacteria are considered potential virulence factors for organisms that cause disease or gain entry at mucous membranes. To determine the role of IgA protease in the pathogenicity of mycoplasmal disease, a variety of human and animal mycoplasma and ureaplasma species were examined for IgA protease activity with human, murine, porcine, and canine IgA. None of the mycoplasma species examined showed detectable IgA protease activity with any of the IgAs tested. Twenty-eight strains of Ureaplasma urealyticum isolated from human urogenital tissues cleaved human IgA1, but no cleavage of human IgA2 or murine, porcine, or canine IgA was observed. Ureaplasmas isolated from nonhuman hosts (feline, canine, avian, and bovine [Ureaplasma diversum]) did not cleave human IgA1. Two strains of canine ureaplasmas were able to cleave canine IgA, but not murine IgA. Thus, ureaplasmas from other species can produce IgA protease, but the specificity of the enzyme was restricted to the IgA of the appropriate host. This finding suggests that IgA proteases could play a role in the selective host specificity of mucosal pathogens.

Animals↗
PubMed1985

Urethral infection in male chimpanzees produced experimentally by Mycoplasma genitalium.

Four young male chimpanzees were inoculated intra-urethrally with a strain (G37) of Mycoplasma genitalium which had been isolated from the urethra of a patient with non-gonococcal urethritis. Two of the chimpanzees became infected as indicated by persistent recovery of the organisms from the urethra for 13 weeks and by an antibody response measured by both metabolism inhibition and micro-immunofluorescence techniques. The numbers of organisms isolated from both animals increased about 4 weeks after inoculation and antibody development was first detected 1 week later. The infected animals developed a minimal and inconsistently detected urethral polymorphonuclear leucocyte response which was not seen in those that were uninfected, nor in a chimpanzee that had been given medium only. The organisms were not isolated and the cellular response was not observed after treatment of the infected chimpanzees with oxytetracycline. One of the animals that had been infected was re-inoculated with strain G37 six months after successful treatment, but although the titre of serum antibody had diminished to its original level urethral recolonization did not occur. The organisms in the inoculum were not attenuated, however, because they infected another chimpanzee that had not had previous experience of M. genitalium. The results are discussed in relation to the potential of this mycoplasma to produce urethritis in man.

Animals↗
PubMed1984

Genomic analysis of avian and feline ureaplasmas by restriction endonucleases.

Genomic relationship among the strains of avian and feline ureaplasmas was determined by restriction analysis. Chromosomal DNAs extracted from the two avian and four feline ureaplasma strains resolved in 1.0% agarose gel electrophoresis following digestion with the restriction enzymes, PstI, BamHI, HindIII, EcoRI, SalI and HpaII. Relationship among the strains was determined from base substitution frequency obtained by comparing the restriction patterns. The guanine plus cytosine (G + C) contents of the representative strains of avian and feline ureaplasmas were estimated by high-performance liquid chromatography to be 27.6 and 27.1 mole %, respectively. Restriction patterns of the avian and feline ureaplasmas were distinct from those of the human and bovine strains, but they were relatively similar within a serotype.

Animals↗
PubMed1984

Immunization against Mycoplasma pneumoniae disease: a review.

There have been three basic approaches to vaccine development: inactivated, live attenuated, and purified cell component vaccines. With rare exception, inactivated vaccines have proved disappointing. Because men and animals recovering from naturally occurring diseases are resistant to rechallenge, the effectiveness of live vaccines was thought promising. However, the only live mycoplasma vaccine effective under field trial conditions is that prepared from Mycoplasma mycoides subsp. mycoides for prevention of bovine pleuropneumonia. Because of this, investigators have searched for the active, protective antigens (immunogens) responsible for exciting the optimal immune parameters responsible for protection. Generally, the toxic and virulent components of the pathogen are the protective antigens, because the host must defend itself against these noxious, tissue-damaging components. The major virulence factors of M. pneumoniae are probably the attachment, ciliotoxic, mitogenic and possibly protease components. Preventing attachment may prevent disease; preventing tissue damage may reduce severity of disease. Although the metabolism inhibition antibodies inhibit growth, are opsonic and mycoplasmacidal, they are probably not involved in protection, but rather in resolution of disease. A protein extract containing attachment, ciliotoxic, mitogenic and peptidase activity was shown to protect hamsters from challenge with virulent M. pneumoniae when given first i.p. and then intratracheally. Because mycoplasma disease suppresses T-helper cells and causes nonspecific activation of B cells, future vaccines must be free of such activity. They must protect without stimulating untoward reactions or adverse immunologic responses.

Animals↗
PubMed1983

Intraspecies genetic relatedness among strains of Acholeplasma laidlawii and of Acholeplasma axanthum by nucleic acid hybridization.

This study compares the intraspecies genetic relatedness among strains of two established species of Acholeplasma. Radiolabelled DNA probes were prepared from three strains of Acholeplasma laidlawii and two strains of Acholeplasma axanthum, by using the nick translation method. The labelled DNA probes of these two strains were hybridized to an excess of unlabelled DNA from 12 strains of Acholeplasma laidlawii and from six strains of Acholeplasma axanthum, respectively. Nucleic acid hybridization analyses showed a wide variation among strains within each of the two established species, ranging from 48 to 100% homology. The results demonstrate that strains isolated from diverse hosts and habitats within a given species of Acholeplasma exhibit extensive genotypic variations.

Acholeplasma↗
PubMed1983

DNA cleavage patterns as indicators of genotypic heterogeneity among strains of Acholeplasma and Mycoplasma species.

Electrophoretic patterns of digestion products of Acholeplasma and Mycoplasma DNA by restriction endonucleases were compared. The patterns of Acholeplasma axanthum strains isolated from a variety of hosts and habitats differed markedly from each other, indicating considerable genotypic heterogeneity among strains included in this species. Heterogeneity was less marked among the Acholeplasma oculi strains tested, and was minimal among strains of the avian pathogen Mycoplasma gallisepticum. Strains of Mycoplasma genitalium isolated from the urethra of patients with non-gonococcal urethritis and from the urethra of an experimentally infected chimpanzee yielded identical cleavage patterns, indicating a high degree of genetic homogeneity of these strains. The data support the notion that mycoplasma species of strict host and tissue specificity exhibit marked genetic homogeneity. The advantages and deficiencies of the use of DNA cleavage patterns for classification purposes are discussed.

Acholeplasma↗
PubMed1983

Nucleic acid relationships among Acholeplasma species.

3H-labeled Acholeplasma DNA probes were generated in vitro by the nick-translation method and used to determine the nucleotide sequence homology among the type strains of the eight currently recognized species of Acholeplasma. Very little nucleotide sequence homology (less than or equal to 18%) was found among the eight species, with heteroduplexes showing at least 12% or more mismatching as determined by thermal elution midpoints. The small amount of nucleotide sequence homology among the eight species indicates that these species are quite distinct and are not closely related to each other genomically.

Acholeplasma↗
PubMed1982

Attachment of Mycoplasma pneumoniae to hamster tracheal organ cultures, tracheal outgrowth monolayers, human erythrocytes, and WiDr human tissue culture cells.

Virulent strains of Mycoplasma pneumoniae, PI-1428 and M129, were radiolabeled wtih [3H]palmitic acid or [3H]thymidine and examined for attachment to hamster tracheal organ cultures, tracheal outgrowth monolayers, human O-positive erythrocytes, and human WiDr carcinoma cell cultures. Although attachment to each cell substrate was readily detected, the WiDr cell culture monolayers provided the most satisfactory substrate for quantitating mycoplasma attachment. Serious technical limitations were encountered with each of the other substrates that we examined; these limitations interfered with reproducibility or sensitivity and rendered tracheal organ cultures and erythrocyte suspensions unsuitable for routine attachment and attachment inhibition assays. Moreover, the WiDr cell monolayer was the most sensitive substrate for determining attachment inhibition activity in protein-containing extracts prepared from M. pneumoniae. The significance of these findings is discussed.

Adhesiveness↗
PubMed1982

Mycoplasma pneumoniae attachment: competitive inhibition by mycoplasmal binding component and by sialic acid-containing glycoconjugates.

Attachment of Mycoplasma pneumoniae to human WiDr cell culture monolayers was examined by using radiolabeled M. pneumoniae. The amount of attachment was proportional to the density of the WiDr cells and to the concentration of M. pneumoniae in the assay. Saturation of the monolayers was achieved with 40 micrograms of virulent strain M129 per assay, whereas binding of avirulent strain B176 was 70% less than that of strain M129. A competitive attachment inhibition assay was used to measure specific binding component activity. Attachment was inhibited when WiDr cells were pretreated with unlabeled virulent strain M129, whereas avirulent noncytadsorbing strain B176 did not inhibit attachment as well as the virulent strain. A protein-rich extract prepared from virulent, cytadsorbing strains of M. pneumoniae also inhibited attachment. The amount of inhibition was dependent on the amount of extract used, and units for binding component activity in the extract were calculated from the competitive attachment inhibition assays. The competitive attachment inhibition assay was also used to investigate the nature of the receptor site on the WiDr cells. Attachment was inhibited when the radiolabeled M. pneumoniae suspensions were pretreated with human sialoglycoproteins, such as orosomucoid and ceruloplasmin, and bovine gangliosides. These findings support the present concept that the mammalian receptor site for M. pneumoniae is a sialic acid-containing glycoprotein.

Bacterial Proteins↗
PubMed1982

Genomic and phenotypic analyses of Mycoplasma pneumoniae strains.

Mycoplasma pneumoniae strains PI-1428, M129, B176, FH, and MAC were analyzed for homology by DNA-DNA hybridization, thermal elution midpoints of the DNA-DNA heteroduplexes, DNA cleavage patterns with restriction endonucleases, and protein gel electrophoretic profiles. These properties were compared with biological assays, such as antigenic reactivity with reference antisera in the growth inhibition and metabolic inhibition tests, as well as the ability to attach to human WiDr cell cultures. The avirulent, nonhemadsorbing strain B176 could be differentiated from the others by diminished attachment capacity to WiDr cells and by slightly reduced DNA homology. The other strains appeared to be identical when examined by these procedures. No significant differences were detected among any of the strains by the metabolic inhibition or growth inhibition tests. The DNA cleavage patterns of the five strains were also similar, although strains FH and MAC differed from the other three strains in a few bands. These results demonstrate that these five strains are similar and that the species M. pneumoniae is remarkably homogeneous.

Adhesiveness↗