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Query: UMLS:C0026936 (Mycoplasma)
 14,761 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The morphology of Ureaplasm urealyticum in broth cultures was studied by phase-contrast microscopy. Most organisms appeared singly or in pairs. Long filaments and long chains of cocci, common in classical mycoplasma cultures, were not observed. On solid medium, U. urealyticum produced "fried-egg" colonies which developed according to the scheme suggested by Razin and Oliver (J. Gen. Microbiol., 1961) for the morphogenesis of the classical mycoplasma colonies. The formation of the peripheral zone of the colonies followed that of the central zone only when growth conditions were adequate, Hence, the appearance of peripheral zones, and consequently the larger colony size, can be taken as an indicator of improved growth conditions. Incubation in an atmosphere of 100% CO2 resulted in significantly larger colonies than in an atmosphere of N2, O2, or air. CO2 acts as a buffer, keeping the pH at the optimal range for Ureaplasma growth (pH 6.0 to 6.5) in the presence of the ammonia produced from the urea hydrolyzed by the organisms. The addition to the medium of 0.01 M urea together with 0.01 M putrescine enabled better growth than with urea alone. Small amounts of phosphate improved growth in an atmosphere of CO2, apparently fulfilling a nutritional role. Under nitrogen, higher phosphate concentrations were required for good growth, apparently serving as a buffer as well as a nutrient. Sodium chloride and sucrose which had been added to increase the tonicity of the medium inhibited growth above 0.1 M. An increase in the agar concentration above 2% resulted in decreased colony size. Likewise, prolonged drying of the agar plates caused a marked decrease in colony size, mostly affecting the peripheral zone. The addition of both urea and putrescine to the growth medium and incubation in a humidified CO2 atmosphere are recommended for improved growth and formation of fried-egg colonies of U. ureaplyticum on agar. It must be emphasized that these experiments were carried out with a laboratory-adapted strain.
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PMID:Morphology of Ureaplasma urealyticum (T-mycoplasma) organisms and colonies. 1 86

The protective efficacy of a formalin-inactivated Mycoplasma pneumoniae vaccine was evaluated in a double-blind fashion in 7,861 Marine Corps recruits at Parris Island, South Carolina. Vaccine, administered in a 1-ml dose by a jet-injection device, was glass-grown and contained 264 microgram of protein nitrogen/ml. Phosphate-buffered saline with formalin was injected as a control. Systemic reactions to injection were similar in both groups, but the percentage of vaccinees with erythema (51%) and induration (52%) at 24 hr was significantly greater than the percentage of controls (2%) with these reaction (P less than 0.001). Twenty-one (0.5%) of 3,930 vaccinees and 43 (1.1%) of the 3.931 placebo recipients were hospitalized with pneumonia (chi2=7.61; P less than 0.01). Ten of 21 vaccinees and seven of 43 controls with pneumonia had a positive pharyngeal culture for M. pneumoniae (chi2=1.69; P =0.20), and fourfold rises in titer of serum antibody were noted in five of 14 vaccinees and in 15 of 28 placebo recipients with pneumonia (chi2=7.90; P less 0.0005). Therefore, vaccine efficacy for M. pneumoniae-specific pneumonia was 42% as determined by cultures and 67% by serologic tests. The vaccine showed no protective efficacy for M. pneumoniae-specific bronchitis or for M. pneumoniae pharyngeal carriage in recrutis in training.
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PMID:Protective efficacy of an inactivated Mycoplasma pneumoniae vaccine. 89 86

Finely minced explants from 54 TCC2 of the human urinary tract were cultured in vitro in an attempt to establish cell lines. Cells with epithelial morphology grew out from 48 tumor explants, and long-term cell cultures were established from 10. Six of the cell cultures have been maintained for over 18 months with 50 to 70 transfers and, therefore, are considered permanent cell lines. The epithelial cells in the established cultures are small, exhibit rapid doubling time, and show multilayering. The cells were examined both microscopically and by cultivation techniques, and they were found to be free from contaminating microorganisms, including Mycoplasma. The established cultures grow rapidly in roller bottles and, therefore, can be produced in large quantities. These cells also remain viable after being stored for 3 years in liquid nitrogen.
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PMID:In vitro cultivation of epithelial cells derived from tumors of the human urinary tract. 94 89

After almost forty years of its introduction, erythromycin will not be the exclusive member of the macrolide group of antibiotic agents, but a new generation of its derivatives which surpass it in pharmacological properties and clinical efficacy will also be available. Clarithromycin, a 14-membered derivative, has shown acid stability, longer half-life, lower protein binding and higher lung tissue penetration. Its exceedingly high activity against erythromycin-susceptible gram-positive cocci, Mycoplasma pneumoniae, and Legionella pneumophila makes it and important alternative choice in the therapy of respiratory tract infections. Also, it has shown high activity against Chlamydia trachomatis, and high urinary clearance of this unmetabolized molecule, important properties which would render it a special role in the treatment of genitourinary tract infections. Azithromycin, a 15-membered derivative has shown enhanced basicity (due to the nitrogen atom in its lactone ring), longer half-life and lower protein bindings. Its exceptional activity against Hemophilus influenzae, Branhamella catarrhalis, Neisseria gonorrhoeae, Ureaplasma urealyticum and gram-negative bacteria, and its high concentration in tonsillar, pulmonary, prostatic and female reproductive tract tissues, assigns it an honorific place among the macrolides in the therapy against respiratory tract and genitourinary tract infections. Its role against T. gondii deserves further study, but points out this agent as a promise against this parasite.
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PMID:The new macrolides: expanding the ways in antibiotic treatment. 150 85

Previous studies have shown that exposure to nitrogen dioxide at concentrations of 5 and 10 parts per million (ppm) decreases intrapulmonary killing of Mycoplasma pulmonis, and that this decrease is related to increased lung lesions and mortality. The specific objectives of the present study were to titrate the effects of nitrogen dioxide on pulmonary clearance of M. pulmonis, determine the mechanisms by which this organism is killed within the lungs, and determine the target that the nitrogen dioxide affects. Pathogen-free C57BL/6N mice were exposed to 0, 0.5, 1, 2, or 5 ppm of nitrogen dioxide (contamination with other oxides of nitrogen compounds was 5% or less) for four hours and then immediately were exposed to aerosols of viable, radiolabeled M. pulmonis strain UAB CT. One-half of the animals in each group were killed immediately after exposure to the infectious aerosols, and the rest were killed 24 hours later. The amount of radioactivity and the number of viable M. pulmonis were determined for each group. Exposure to less than 5 ppm of nitrogen dioxide had no effect on intrapulmonary killing of M. pulmonis, although exposure to 1 ppm of nitrogen dioxide did increase mechanical removal. We were unable to develop a completely in vitro mycoplasma killing method. However, we were able to demonstrate the in vitro killing of M. pulmonis that had been allowed to associate with alveolar macrophages in vivo. Thus, mouse lungs contain unidentified factors that allow cells to kill M. pulmonis. Furthermore, we obtained evidence that suggests that prior exposure to nitrogen dioxide abrogates killing in these experiments. We also have shown that exposure to nitrogen dioxide does not increase the protein content of bronchoalveolar lavage fluid. Using immunofluorescence, more than 95% of the cells recovered by lavage were macrophages; with double-label immunofluorescence, more than 98% of the cell-associated mycoplasmas were on or in alveolar macrophages. In assessing the cytological parameters of lung lavage cells from mice exposed to nitrogen dioxide, M. pulmonis, or both, we found that both insults affected the viability of recovered macrophages. Viability immediately after exposure as measured by trypan blue exclusion or by fluorescein diacetate uptake, was 89% +/- 4% and 88% +/- 4% in the control group, respectively; 56% +/- 19% and 64% +/- 11% in the group receiving M. pulmonis alone; 23% +/- 7% and 48% +/- 9% in the group receiving nitrogen dioxide alone; and 16% +/- 6% and 25% +/- 6% in the group receiving both M. pulmonis and 10 ppm nitrogen dioxide exposures.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Murine respiratory mycoplasmosis: a model to study effects of oxidants. 183 26

Tissues from products of conception were examined to determine the feasibility of obtaining viable neural tissue after suction abortion at 9-12 weeks of gestation. The ventral mesencephalon, a prototype region whose maturation can be monitored and which is a potential tissue for transplantation, was identified in 32 of 120 cases. The tissue was then screened for the presence of infectious agents, while being held at -196 degrees C in cryopreservative solutions. Three of 32 specimens were found to be contaminated by normal vaginal bacteria; all other viral, fungal, and mycoplasma testing was negative. Thawed brain fragments retained high viability after storage in liquid nitrogen and when grown in vitro exhibited neuronal morphology, tyrosine hydroxylase immunoreactivity, and dopamine production. We have demonstrated that human fetal brain tissue can be cryopreserved in a manner which not only retains viability but allows normal phenotypic differentiation after thawing.
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PMID:Cryopreservation of human brain tissue. 196 97

A marked enhancement was seen in activities of mouse splenic natural killer (NK) cells and macrophages one week after infection with Mycoplasma pulmonis (Mp) or exposure to nitrogen dioxide (NO2). Macrophage activity of the Mp-infected mouse showed further augmentation by exposure to NO2 while NK activity of Mp-infected mice was not affected by NO2-exposure.
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PMID:Effects of Mycoplasma pulmonis infection and exposure to nitrogen dioxide on activities of natural killer cells and macrophages of the mouse. 204 74

The effects of continuous exposure to nitrogen dioxide (NO2) on the pathologic and immunologic responses of ddY mice to the infection with Mycoplasma pulmonis were investigated. The organisms grew well in the trachea as early as 7 days after infection but barely grew in the lung even after 28 days, causing slight pneumonic lesions in only a few of the infected mice exposed to 1 and 5 ppm NO2. When mice were exposed to 10 ppm NO2 at or after the infection, however, mycoplasmal growth in the lung, but not in the trachea, was greatly enhanced, and pneumonic lesions were evident in the lung of almost all the mice examined. The serum antibody titers to M. pulmonis increased with time after infection regardless of the concentration of NO2 exposed or the mycoplasmal number in the respiratory tract in the infected mice. The in vitro immune responses of the spleen cells of the infected mice were significantly depressed by exposure to 10 ppm NO2 in not only mitogenic response to LPS and ConA but also antibody production to SRBC, whereas uninfected healthy mice were apparently not modulated except for a slight decrease in Con A response.
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PMID:Effects of nitrogen dioxide on Mycoplasma pulmonis infection and humoral immune responses in mice. 325 Oct 88

The growth of Mycoplasma equigenitalium and Mycoplasma subdolum from specimens collected from the clitoral fossa of each of four Standardbred mares was not diminished by freezing of the specimens in liquid nitrogen (-196 degrees C) for up to 30 days when compared to samples cultured immediately.
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PMID:Effect of sample freezing on the isolation of Mycoplasma spp. from the clitoral fossa of the mare. 334 94

The growth of Mycoplasma mycoides subspecies mycoides strain T1 on media containing various sugars, tryptose, yeast extract, salts and either pig or calf-serum or a mixture of bovine serum albumin (BSA) plus lipid was followed by ampoule microcalorimetry. Power-time (p-t) curves were reproducible and showed details of growth not observable by conventional microbiological techniques. In media with metabolisable sugars p-t curves typically showed three periods of exponential increase in power separated by transient declines or plateaux. Maximum power (Pmax) was dependent upon the nature and concentration of sugar, whether ampoules were capped in air or nitrogen, and whether the medium contained pig or calf-serum or BSA plus lipid. The highest Pmax was observed in pig-serum medium with glucose, in ampoules capped in air. Decline in power from Pmax was essentially exponential.
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PMID:Growth of Mycoplasma mycoides subspecies mycoides on media containing various sugars and amino sugars: an ampoule microcalorimetric study. 352 Feb 45


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