Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “mycoplasma”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources
PubMed1978

[Mycoplasma synoviae control. I. Studies on the thermal sensitivity of pathogenic avian mycoplasmas (Mycoplasma synoviae, Mycoplasma gallisepicum and Mycoplasma meleagridis)].

A number of experiments were carried out to study the thermal sensitivity of Mycoplasma synoviae and Mycoplasma gallisepticum as well as that of young embryos in vitro and in ovo. A full mycoplasmacidal effect was attained after heating in bouillon cultures for six hours at 45 degrees C (including cultures of Mycoplasma meleagridis), for two and a half hours at 50 degrees C, for ninety minutes at 52 degrees C and for thirty minutes at 55 degrees C. Yoder's method of heating to control these mycoplasmas in hatching eggs was found to be inadequate. When inoculated eggs were heated for ten hours at 45 degrees C, mycoplasmas could no longer be isolated; however, this had a highly adverse effect on the proportion of eggs hatched (33 and 50 percent for hen's eggs and turkey eggs respectively). Mycoplasma synoviae was slightly more sensitive to heating than Mycoplasma gallisepticum, whereas Mycoplasma meleagridis showed more resistance than Mycoplasma gallisepticum. After heating, atypical colonies constantly appeared on the primary plates and conversion of glucose was delayed in the cultures. Isolation by SPF embryos was found to be a more sensitive method than isolation using artificial culture media only. When fresh incubated eggs were heated for ten hours at 45 degrees C, for two and a half hours at 46 degrees C or for thirty minutes at 47 degrees C, fifty percent of embryos died, whereas one hundred per cent died after heating for sixty minutes at 47 degrees C. Thermal treatment of hatching eggs to eliminate Mycoplasma synoviae, Mycoplasma gallisepticum and Mycoplasma meleagridis is unsuitable for use in poultry practice.

Animals↗
PubMed1978

Culturing anomalies associated with Mycoplasma recovered from the tissues of chicks and turkey poults experimentally infected with Mycoplasma gallisepticum or Mycoplasma gallinarum.

Tissues of mycoplasma infected chicks and turkey poults were cultured and subcultured on mycoplasma agar. Usually, colonies which grew on the agar initially inoculated could be subcultured, but sometimes they could not. At other times, colonies were not seen on the agar initially inoculated but appeared on the subcultured plate.

Animals↗
PubMed1979

The incidence of Mycoplasma dispar, Ureaplasma and conventional Mycoplasma in the pneumonic calf lung.

This report describes the incidence of Mycoplasma dispar, ureaplasma and conventional (large colony) mycoplasma isolated from the pneumonic lungs of groups of young calves and the identification to species level of mycoplasmas in mixed populations with the aid of the indirect fluorescent antibody test. Pneumonic lung tissue yielded one or more mycoplasma species from 88% of the 153 calves cultured. The mycoplasmas identified and percent of the calves with lungs positive for each species were: M. dispar (56%), ureaplasma (44%), Mycoplasma bovis (37%), Mycoplasma arginini (33%) and Mycoplasma bovirhinis (23%). Conventional mycoplasmas isolated from two calves (1%) could not be identified using the antisera available.

Animals↗
PubMed1979

Haemadsorption inhibition test for the identification of Mycoplasma gallisepticum and Mycoplasma synoviae.

Colonies of the avian mycoplasma strains Mycoplasma gallisepticum S6 and Mycoplasma synoviae WVU 1853 and two Mycoplasma synoviae isolates from this laboratory were shown to be haemadsorption positive for chicken erythrocytes. Three Mycoplasma synoviae isolates from this laboratory proved to be haemadsorption and haemagglutination negative. The haemadsorption of the mycoplasma colonies mentioned above was inhibited with specific antisera of either high or low titre. No cross-inhibition was observed. It is suggested that this test could be used for a quick tentative identification of the two avian mycoplasmas on primary solid-medium cultures.

Animals↗
PubMed1977

Mycoplasma and mycoplasma mastitis.

Mastitis due to mycoplasma has been reported sporadically from several countries in Europe, Australia, Israel, New Zealand, and many states in the United States. Most reported occurrences are due to Mycoplasma bovis, but 5 other mycoplasmas are reported to cause mastitis. A total of 5 species of mycoplasma have been isolated from cows with mastitis in California. Therapy trials with M bovis infections have not been encouraging. Recovery is slow, and shedding of mycoplasma into milk of apparently recovered cows for an indefinite period is common.

Animals↗
PubMed1978

Serologic studies of human genital mycoplasmas: distribution of titers of mycoplasmacidal antibody to Ureaplasma urealyticum and Mycoplasma hominis in pregnant women.

Titers of mycoplasmacidal antibody to the human genital mycoplasmas Ureaplasma urealyticum and Mycoplasma hominis were determined using genital isolates from pregnant patients as antigens and comparing these isolates with the 11 prototypic reference strains for U. urealyticum and the seven reference strains for M. hominis. Virtually all titers that were detected with use of the patient's own isolates were detected by the 11 reference strains of U. urealyticum and by the seven reference strains of M. hominis. Serologic surveys of pregnant women who harbored either or both mycoplasmas in vaginal cultures indicated that antibody to M. hominis was found more commonly than antibody to U. urealyticum. It was demonstrated that significant postpartum rises in titers of antibody to M. hominis were correlated with the presence of these mycoplasmas in genital cultures. Postpartum rises in titer of antibody were particularly likely to occur in women with low titers of mycoplasmacidal antibody in serum at the time of delivery. Approximately 88% of the women who were colonized with M. hominis showed significant changes in titer of antibody to M. hominis throughout an apparently normal pregnancy; only 40% of the women who were colonized with U. urealyticum showed such changes in titers to U. urealyticum. Statistical analysis showed that mean log titers of antibody to both mycoplasmas at the first prenatal visit were significantly associated with the number of pregnancies experienced by these women.

Antibodies, Bacterial↗
PubMed1978

The effect of pneumonia induced in mice with Mycoplasma pulmonis on resistance to subsequent bacterial infection and the effect of a respiratory infection with Sendai virus on the resistance of mice to Mycoplasma pulmonis.

The effect of pneumonia induced by Mycoplasma pulmonis in mice on the resistance of the lung to additional bacterial infection was examined. The effect of pneumonia induced by Sendai virus on the resistance of mice to M. pulmonis was also investigated and compared with the effect of Sendai virus on resistance to Staphylococcus aureus. Sendai virus infection decreased subsequent resistance to M. pulmonis in proportion to the virus dose. Decreased resistance to subsequent S. aureus and M. pulmonis infection was greatest at about the same time after inoculation of virus and was related to virus-induced lesions. Besides affecting the resistance of mice to subsequent mycoplasma infection, Sendai virus could enhance an existing mycoplasma infection. Pneumonia induced by M. pulmonis did not decrease resistance to subsequent bacterial infection. The mechanism whereby Sendai virus decreases host resistance is therefore similar for bacteria and mycoplasmas, but pneumonia induced by mycoplasmas does not have the same effect.

Animals↗
PubMed1975

Canine mycoplasmas: serological studies of type and reference strains, with a proposal for the new species, Mycoplasma opalescens.

The type and reference strains of all Mycoplasma species or "serogroups" presently known to occur in dogs were compared serologically. Tests of growth inhibition and metabolism inhibition as well as indirect immunofluorescence tests did not disclose any cross reactions. Examination by double immunodiffusion revealed at least one antigen specific for each strain tested. In addition, the common antigens were found within the glucose fermenting group and within the arginine metabolizing group of Mycoplasma strains, respectively. No antigens were shared by these groups. The arginine positive strain MH5408, serogroup D was found to differ serologically from all other arginine positive Mycoplasma species. Serogroup D is therefore a new species for which the name Mycoplasma opalescens is proposed. The type strain is MH5408 (ATCC 27921 and NTCC 10149). Finally, serological data are presented which relate strain HRC689 to M. mycoides.

Animals↗
PubMed1978

Detection of Mycoplasma hominis and Mycoplasma orale in cell cultures by immunofluorescence.

Mycoplasma contaminants of animal and human cell cultures were rapidly detected and identified by an indirect immunofluorescent technique. Cells suspected of being contaminated by mycoplasmas were grown as monolayers on chamber slides in a culture medium selected to promote mycoplasmal growth. Before fixation by acetone, the monolayers were subjected to a hypotonic treatment to cause swelling of the mycoplasmas. Detection and identification were then performed by indirect immunofluorescence using rabbit antisera to various mycoplasma species. The correlation between results obtained by the standard isolation procedure and those obtained by this method was very close.

Animals↗
PubMed1979

Differentiation of Mycoplasma mycoides subsp. mycoides from certain closely related caprine mycoplasmas by mycoplasmaemia and cross-protection tests in mice.

In recent years, mycoplasma taxonomists have found that numerous mycoplasma strains from goats are serologically indistinguishable from Mycoplasma mycoides subsp. mycoides, the causative agent of contagious bovine pleuropneumonia (CBPP), by routinely used tests, e.g. the metabolism- and growth-inhibition tests. As a result, such organisms are now openly referred to as M. mycoides subsp. mycoides. Seven of these so-called M. mycoides subsp. mycoides strains from goats were compared with two strains of M. mycoides subsp. mycoides from CBPP, and with one strain of M. mycoides subsp. capri, by means of two in-vivo tests, namely, (1) a test of the ability of each strain, injected intraperitoneally into mice, to produce mycoplasmaemia, and (2) a cross-protection test in mice. Of the seven strains, only one ('O goat') was indistinguishable from genuine M. mycoides subsp. mycoides; it also had small colonies resembling those of genuine M. mycoides subsp. mycoides. The other six were easily distinguished from genuine M. mycoides subsp. mycoides, and they produced large colonies. These six strains and others like them should no longer be given a name that fails to distinguish them from the causative agent of CBPP. Cross-protection tests showed that the seven goat strains referred to above differed from M. mycoides subsp. capri.

Animals↗
PubMed1979

[Effect of Mycoplasma arthritidis on mouse and rat lymphoid cells in experimental Mycoplasma infection].

Early stages of mycoplasma infection of mice and rats were accompanied by suppression of the populations of rosette- and plaque-forming cells. Later the character and dynamics of the immune response to M. arthritidis differed in mice and rats. In mice mycoplasma infection was accompanied by stimulation of rosette-forming cells with some suppression of the plaque-forming cells from the 7th to the 36th day of infection. In rats by the 7th day the number of plaque- and rosette-forming cells decreased in comparison with control, and the immune response was restored by the 15h day; at later periods the immune response of the infected rats exceeded the normal level considerably. The cellular and humoral immune reactions proved to depend on the mycoplasma dose.

Animals↗
PubMed1979

[Studies of Mycoplasma mastitis in cattle. 7. Mycoplasma mastitis in 3 dairy cattle herds].

Reported in this paper is the occurrence of enzootic mastitis in three dairy cattle stocks. The outbreaks had been caused by Mycoplasma bovis, Acholeplasma laidlawii, Acholeplasma axanthum as well as by one unidentified strain of the family of mycoplasmataceae. All animals with positive response to mycoplasma tests were identified an selected by repetitive testing of cultures in milk samples which had been taken from all lactating and dry cows and heifers as well as by evaluation of organ samples obtained from slaughtered cows. Regular cleaning and disinfection of stands in cowsheds, cattle tracks, and milk parlours as well as disinfection of udders and milking cups worked extremely well throughout the action in control of those cases of enzootic mycoplasma mastitis.

Acholeplasma↗
PubMed1979

Preparation of competent single-cell suspensions of Mycoplasma hominis tets and Mycoplasma salivarium tets for genetic transformation to tetracycline resistance by DNA extracted from Mycoplamsa hominis tetr.

DNA extracted from Mycomplasma hominis (Sprott strain), resistant to 100 micrograms of tetracycline/ml transformed M. hominis strain H29 and Mycoplasma salivarium strain S9, which are sensitive to 2.5 and 5.0 micrograms of tetracycline/ml, respectively, to resistance. The transformants were selected on agar medium containing 10 micrograms of tetracycline/ml. Some transformants were resistant also to 20 micrograms of tetracycline/ml, a finding confirming that transformation occurred between homologous and heterologous species and that resistance is stepwise and controlled by several genetic loci. Medium containing 10 micrograms of tetracycline/ml was bacteriostatic. Prototype experiments employing mixtures of strains that were tetr and tets (tetracycline-resistant and tetracycline-sensitive, respectively) demonstrated that tetr mutants and transformants formed typical fried-egg colonies when mixtures containing not more than 10(9) mycoplasmas were spread on tetracycline agar plates. No mutants to tetracycline resistance were detected. Both M. hominis and M. salivarium were competent after treatment with MgCl2 and CaCl2, while Mycoplasma orale type 2 was inactivated. During DNA extraction different quantities of DNA formed insoluble precipitates with protein, thus preventing quantitative experiments.

Calcium Chloride↗
PubMed1979

Interaction of Mycoplasma pneumoniae with alveolar macrophages: viability of adherent and ingested mycoplasmas.

Guinea pig peritoneal or alveolar macrophages were inoculated with Mycoplasma pneumoniae cells. Extracellular mycoplasms were killed by complement treatment, and the effect of macrophage action on the number of the remaining viable mycoplasmas was observed. The complement killing was to some extent inhibited by the presence of the macrophages, but the mechanism of this protection remains unknown. Opsonized mycoplasmas were ingested, and approximately 98% were killed within 4 h. The killing rate was somewhat lower than comparable data for bacteria, but lack of cell wall and high lipid content of the membrane apparently do not cause a significant delay in intracellular destruction.

Animals↗
PubMed1979

[Studies of bovine Mycoplasma mastitis. 2. Testing of various culture media and culture methods for the isolation of Mycoplasma from milk samples].

The recipes Medium-I broth, Medium-B broth, and Weissenseemycoplasma broth as well as Medium-I agar, Medium-B agar, and MRL agar were tested for their applicability to culturing mycoplasma from milk samples, using the direct and indirect techniques. No dependable information on the occurrence of mycoplasma was obtainable from tested material unless several nutritive media and techniques were combined. Medium I, for which almost no imported substances were needed, was in no way inferior to common international nutritive substrates. Its use in conjunction with the indirect culturing technique is recommended for routine diagnosis.

Animals↗
PubMed1979

[Studies of Mycoplasma mastitis in cattle. 6. Testing of Mycoplasma isolated from milk for udder pathogenicity].

Strains of M. bovis, A. laidlawii, A. axanthum, and one unidentified strain of the family of mycoplasmataceae as well as altered secretion obtained from cows with mastitis were intracisternally applied in experiments and proved to be pathogenic to cattle udder. The results are likely to suggest the importance of mycoplasma isolated from the milk of mastitis cows to the aetiology of enzootic mastitis in three large dairy cattle stocks. Intravenous application of M. bovis and A. laidlawii caused neither mastitis nor mycoplasma secretion in the milk.

Acholeplasma laidlawii↗
PubMed1979

UV survival of human mycoplasmas: evidence of dark reactivation in Mycoplasma buccale.

The inactivation by ultraviolet (UV) light irradiation of mycoplasma cells of five human strains was monitored by investigating the colony-forming ability. The survival curves of five strains tested indicated that the cells of Mycoplasma buccale only are single and homogenously susceptible to UV light. The effect of the repair inhibitor, caffeine, on the colony-forming ability of UV-irradiated cells was investigated with M. buccale because of its homogenous susceptibility to UV light. The colony formation of irradiated cells was markedly depressed by post-irradiation treatment with caffeine at concentrations that had little or no effect on the colony formation of unirradiated cells. The colony-forming units (CFU) of UV-irradiated cells which were kept in broth without caffeine in the dark increased without a lag as the time in the dark increased. The colony-forming ability of the irradiated cells completely recovered after 3 hr in the dark. However, when irradiated cells were kept in the presence of caffeine, no increase in their CFU was observed. The mode of action of caffeine on UV-irradiated cells closely resembles that described for other organisms which possess dark reactivation systems for UV-induced damage in deoxyribonucleic acid (DNA). Thus, the results obtained provide evidence for the existence of a dark repair function in M. buccale.

Caffeine↗