Evidence supporting an intratrial interpretation of delayed response performance of monkeys.
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Biomedical subjects
Publications and source records attributed to J K Davis.
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Ureaplasma urealyticum is commonly isolated from the amniotic fluid of unselected individuals with intact membranes at the time of cesarean section even prior to onset of labor. The risk of placental infection increases with onset of labor, rupture of membranes and number of vaginal examinations. Qualitative cultures of women with clinical signs of intraamniotic infection and matched controls indicate that U. urealyticum can be found in 50% of amniotic fluid samples of both groups thus suggesting that it may not be a cause of clinical amnionitis. To gain further understanding of the potential role of this organism, we performed amniotic fluid and blood cultures and measured serologic responses by enzyme-linked immunosorbent assay in women with clinical intraamniotic infection and matched controls. U. urealyticum was the single most common bacterial species isolated from maternal blood and amniotic fluid but the isolation rate did not differ between symptomatic and asymptomatic women. Also other known pathogenic bacteria were often isolated from amniotic fluids containing ureaplasmas. However, the marked difference in serologic response between symptomatic and asymptomatic women and the occurrence of ureaplasmemia in some suggest that in certain individuals U. urealyticum may be a cause of clinical amnionitis. Serologic responsiveness, ureaplasmemia and isolation of ureaplasmas in pure culture from amniotic fluid of some asymptomatic women suggest that U. urealyticum may also be a cause of clinically silent amnionitis. Previous studies have shown a significant association between chorioamnionitis documented by histopathology and isolation of U. urealyticum from the placenta or infant but not the maternal cervix.(ABSTRACT TRUNCATED AT 250 WORDS)
Ureaplasma urealyticum has been subspeciated by a number of serologic methods. Eight serotypes have been identified by modified metabolic inhibition, growth inhibition and indirect hemagglutination. Fourteen serovars have been identified by immunofluorescence and 16 by the mycoplasmacidal assay. The present studies were performed to determine if group-specific antigens could be detected by immunofluorescence and if group- or serovar-specific antigens could be detected by enzyme-linked immunosorbent assay and immunoblotting. Reaction of rabbit antisera to U. urealyticum with homologous and heterologous serotypes based upon end point immunofluorescent titration did not differentiate the serovars into the two biotypes. In attempts to quantitate the number of a given serovar present in clinical specimens, the total number of colonies that were stained often exceeded 100%, suggesting either that the serovars represented in stock cultures are not truly representative of those present in humans or that certain strains express multiple serovar specificities. End point titration in an enzyme-linked immunoadsorbent assay using either whole cells or cell lysates and rabbit antisera failed to distinguish between group and serovars (i.e. in many cases end point titers were only 2-fold lower with heterologous antigens). Furthermore convalescent sera from patients infected with a single serovar failed to induce a serovar-specific response detectable in an enzyme-linked immunosorbent assay. Likewise immunoblotting of one dimensional electrophoretograms with sera from humans known to be infected with a single serovar showed that antibodies against that serovar recognized peptides present in all serovars and reacted with those bands with various degrees of intensity.(ABSTRACT TRUNCATED AT 250 WORDS)
Chronic respiratory disease in rats, resulting from Mycoplasma pulmonis infection, provides a unique opportunity to study the interactions between systemic and mucosal immune systems in a naturally occurring infection of the respiratory tract. In the present studies, an ELISPOT assay specific for the determination of numbers of anti-M, pulmonis antibody forming cells (AFC) was developed. Using this assay, the numbers of IgG, IgM, and IgA AFC in respiratory and nonrespiratory associated lymphoid tissues were determined. The lymphoid tissues associated with the upper respiratory tract, which includes nasal passages and lymph nodes which drain various portions of the upper respiratory tract, were the major site of antibody production. Antibody responses within the lung were minimal. IgM and IgA were the major antibody isotypes produced in each of the tissues examined.
The cervicovaginal and endometrial isolation rates of Ureaplasma urealyticum and Mycoplasma hominis and relevant demographic data were obtained at the time of laparoscopy in 193 women from infertile marriage. For comparative purposes, fertile women undergoing laparoscopy for tubal ligation (n = 56) or other purposes (n = 64) were also cultured. Blacks were more likely than caucasians to be infected with either organism in all population types (p less than or equal to .05); however, no differences were noted in cervicovaginal carriage rates for blacks in different patient populations. M. hominis was isolated more frequently from tubal reanastomosis patients and less often from infertile patients, p less than or equal to .001. No differences were noted among the infertile subpopulations. Although the isolation rate of U. urealyticum from the different patient populations was similar, one subpopulation within the infertile population (male factor) was identified in which the prevalence of ureaplasmal infection of the female's lower genital tract was over twice as high (p less than or equal to .005) as in other infertile women. Yet there were no statistically significant differences in the demographic data of this subpopulation as compared to the population of infertile women as a whole. No other clinical subpopulation with single or multiple diagnoses not including male factor had an increased prevalence of infection. Eighty percent of infected, infertile couples had no clinical evidence of male factor infertility, indicating that only certain individuals are affected. This possibly explains why previous studies involving small numbers of patients without regard to clinical subpopulations have failed to show significant differences between infected and uninfected couples.(ABSTRACT TRUNCATED AT 250 WORDS)
The antigens of Mycoplasma hominis have previously been defined by means of functional assays with rabbit antisera and have been found to be predominantly protein. In this study, sera from humans as well as those from rabbits were shown to recognize protein antigens of M. hominis in an enzyme-linked immunosorbent assay (ELISA) that depended on antigen-binding capacity rather than biologic function. Although the ELISA was more independent of the strain of M. hominis used as antigen than was the mycoplasmacidal test, the use of no single strain allowed detection of more than 87% of positive sera; this observation suggests strain heterogeneity. In contrast to the results of other studies, common surface antigens among the strains of M. hominis used were demonstrated by immunoblot analysis of intact colonies.
Samples from 61 amniotic fluids (33 discolored and 28 clear) collected by amniocentesis between 16 and 20 weeks gestation were cultured for microorganisms. Two of the discolored fluids were positive for Mycoplasma hominis, and two were positive for Ureaplasma urealyticum. Neither organism was isolated from samples of clear amniotic fluids. No other bacteria, viruses, or chlamydiae were isolated from fluids of any patient. The results prove that both M. hominis and U. urealyticum can infect the amnionic sac early in gestation without rupture of the fetal membranes. U. urealyticum was shown to cause a clinically silent, chronic (up to two months) intrauterine infection characterized by an intense inflammatory response. Complications in three of the four patients from whom mycoplasmas were isolated suggest, but do not prove, that mycoplasmal infection of amniotic fluid may have an adverse effect on outcome of pregnancy. Further studies are necessary to substantiate this implication and to determine the relationship between infection and discoloration of amniotic fluid.