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D Taylor-Robinson

Publications and source records attributed to D Taylor-Robinson.

At least 289 records · Page 16Linked to original sources
PubMed1984

Spontaneous abortion--an infectious aetiology?

The role of Chlamydia trachomatis, genital mycoplasmas, Campylobacter spp. and other aerobic and anaerobic bacteria in the aetiology of spontaneous abortion was investigated prospectively in 241 pregnant women at a community hospital. Sixteen women who had threatened abortions were a little younger, of lower social class and had had more previous spontaneous abortions than the 76 women who aborted or the 149 women whose pregnancies were not complicated in the early stages by haemorrhage. The demographic characteristics of the latter two groups of women were similar. C. trachomatis was isolated from the cervix of only one woman and she had no genital-tract bleeding at any stage in her pregnancy. Mycoplasma hominis was isolated most often from the women who had threatened abortions but otherwise the prevalence of the other various micro-organisms was similar in women who had spontaneous abortions, threatened abortions, and in those who had pregnancies uncomplicated by vaginal bleeding. It was clear, therefore, that C. trachomatis played no role in the aetiology of spontaneous abortion in the population studied and there was no suggestion that any of the other micro-organisms were involved either.

Abortion, Spontaneous↗
PubMed1984

Pelvic inflammatory disease after hysterosalpingography associated with Chlamydia trachomatis and Mycoplasma hominis.

A total of 116 women were referred for hysterosalpingography because of primary or secondary infertility. Chlamydia trachomatis was isolated from the cervix of four (3.4%) of the patients whereas Mycoplasma hominis was isolated from 39 (33.6%) of them. Four patients developed acute pelvic inflammatory disease after hysterosalpingography; two of them were chlamydia culture-positive and developed a significant chlamydial antibody response during the course of the disease. One of the other two patients, who developed upper genital-tract infection, was culture positive for M. hominis and developed a significant antibody response to this micro-organism. The results indicate that C. trachomatis should be sought in patients before hysterosalpingography and, if detected, appropriate antibiotic cover should be instituted before the procedure.

Adult↗
PubMed1984

The occurrence of genital mycoplasmas in babies with and without respiratory distress.

Ureaplasma urealyticum organisms (ureaplasmas) were isolated from throat swabs and/or gastric aspirates taken from 22.5% of babies with respiratory distress in a special care unit. The organisms were isolated most frequently (33%) from a small number of babies with severe distress. However, they were recovered only a little less often (26%) from babies without respiratory distress in the unit, and from 19% of healthy babies, all of the aforementioned babies having been delivered vaginally. The numbers of organisms isolated from babies in the various groups were similar. There was, therefore, no clear evidence that ureaplasmas, nor M. hominis which was isolated from two babies only, were associated with respiratory distress. This finding was supported by the isolation of ureaplasmas from only one of 16 babies born by caesarian section, seven of whom developed respiratory distress but were ureaplasma-negative.

Female↗
PubMed1984

Sensitivity of detecting Chlamydia trachomatis elementary bodies in smears by use of a fluorescein labelled monoclonal antibody: comparison with conventional chlamydial isolation.

Commercially produced fluorescein labelled monoclonal antibodies for the detection of Chlamydia trachomatis have recently become available. One is for detecting inclusions in cell culture (culture confirmation) and the other for detecting elementary bodies in smears from potentially infected sites. We have compared the two monoclonal antibodies with our routine isolation method, which utilises Giemsa staining of cycloheximide treated McCoy cell cultures. The culture confirmation system offered no advantages over Giemsa staining for the detection of inclusions in cell monolayers. By contrast, using monoclonal antibody to detect elementary bodies in smears was much quicker and simpler and slightly more sensitive than isolation of chlamydiae in cell culture. For specimens from seven babies with conjunctivitis and from 35 female contacts of men with non-gonococcal urethritis, there was complete agreement between the results of detecting inclusions in culture and those of seeking elementary bodies in smears. For samples from 100 men with non-gonococcal urethritis and from 100 men with gonorrhoea there was 99% and 94% agreement, respectively, between the results of the two tests. Other aspects and possible uses of the new detection system are discussed.

Antibodies, Monoclonal↗
PubMed1984

Interaction between Trichomonas vaginalis and other pathogenic micro-organisms of the human genital tract.

Trichomonas vaginalis organisms were mixed with suspensions of Neisseria gonorrhoeae, Mycoplasma hominis or Chlamydia trachomatis to allow ingestion of these micro-organisms by the trichomonads. Culture studies indicated that gonococci and mycoplasmas were ingested and that the number of intracellular viable organisms decreased rapidly, most gonococci being killed within six hours and all mycoplasmas within three hours. Electron microscopy revealed phagocytic uptake and destruction of these two micro-organisms within the trichomonads, gonococcal degradation being associated with lysosomal enzyme activity. There was no evidence from cultural or electron microscopy studies that C trachomatis organisms persisted in mixed culture with T vaginalis.

Chlamydia trachomatis↗
PubMed1984

Is one swab enough to detect chlamydial infection of the cervix?

Three swabs were taken from the cervix of each of 104 women for the detection of Chlamydia trachomatis. The processing of three swabs instead of one increased the isolation rate by only 2%, and later swabs did not result in the production of more chlamydial inclusions than first swabs. In most clinics, therefore, a single cervical swab is adequate to detect chlamydial infection.

Chlamydia Infections↗
PubMed1984

The infrequent occurrence of mycoplasmas in amniotic fluid from women with intact fetal membranes.

As human genital mycoplasmas have been associated with various forms of reproductive failure, the present study was undertaken to investigate whether M. hominis and U. urealyticum organisms (ureaplasmas) are capable of crossing intact fetal membranes. Nearly 300 women in Denmark and England were investigated. Most of them were seen at about the fourth month of gestation and the remainder towards or at the time of birth, all with unruptured membranes. A swab was taken from the uterine cervix or vagina and M. hominis was isolated from 9% of the women and ureaplasmas from half of them. The presence of these mycoplasmas was not associated with an abnormal outcome of pregnancy. In contrast to the frequent presence of mycoplasmas in the lower genital tract, amniotic fluids obtained by transabdominal amniocentesis or at cesarean section did not contain M. hominis and ureaplasmas were isolated from only one of them. This was associated with the same ureaplasmas serotype being recovered from the cervix and also from the blood of both infant and mother, whose case differed from the others as labor had already started when the amniotic fluid was obtained. Thus, in our populations, we have no evidence that mycoplasmal invasion of the amniotic fluid occurs before the onset of labor. During labor, despite intact membranes, it seems that genital mycoplasmas may occasionally invade the fetal--placental unit, probably by the hematogenous route after strong uterine contractions, or otherwise directly after membrane rupture. Since both these events are followed usually by immediate delivery, there would seem to be insufficient time for the genital mycoplasmas to cause fetal damage.

Amniotic Fluid↗
PubMed1984

Vaginal colonization of pig-tailed macaques by Gardnerella vaginalis.

Ten pig-tailed macaques inoculated intravaginally with Gardnerella vaginalis organisms were colonized for 11-39 days. In contrast, 4 tamarins and 3 chimpanzees inoculated similarly failed to become colonized. Examination of Gram-stained vaginal smears obtained from infected pig-tailed macaques failed to demonstrate clue cells, a feature which is pathognomonic of non-specific vaginitis in humans. Additionally, the pH value, the levels of non-volatile fatty acids and the anaerobic flora of the macaque vagina differed from these aspects of the human vagina. While these differences indicate that gardnerella-infected macaques are unsuitable as a model of gardnerella-associated vaginitis in humans, such animals may prove useful for studying selected aspects of the biology of G. vaginalis such as the adhesion and interaction of the bacteria with the vaginal mucosa.

Animals↗
PubMed1984

The bacteriology of Gardnerella vaginalis.

Even 70 years ago Gram-negative coccobacilli had been recognized in vaginal discharge and were cultured 30 years ago. The need to have blood in agar medium for cultivation suggested that the organisms might be a Haemophilus species. Later, however, growth characteristics and other features resulted in their being placed in the genus Corynebacterium, before it was realized that this was inappropriate and they were transferred to a new genus and species Gardnerella vaginalis. The organisms are Gram-variable, non-sporing, non-flagellate, non-motile coccobacilli of average size 0.4 X 1-1.5 microns. The cell wall is laminated and some strains possess pili. G. vaginalis is fermentative and dextrose, fructose, galactose, glucose, maltose, mannose, ribose and starch are most likely to be metabolized. However, published patterns of the sugars fermented vary widely and most workers do not rely on such tests as a means of identification. Of many other features exhibited by G. vaginalis, the following are outstanding: it does not produce catalase, cytochrome oxidase, hydrogen sulphide, indole, or urease. Nor does it degrade aesculin, liquefy gelatin, reduce nitrate, or decarboxylate arginine, lysine or ornithine. On the other hand, it is sensitive to hydrogen peroxide, often causes beta-haemolysis and usually hydrolyses hippurate and starch. G. vaginalis is serologically heterogeneous and causes haemagglutination which is mannose resistant. It is resistant to several antibiotics, including amphotericin, colistin, nalidixic acid and gentamicin, which may be incorporated in selective media.(ABSTRACT TRUNCATED AT 250 WORDS)

Anti-Bacterial Agents↗
PubMed1984

A colposcopic and histological study of experimental chlamydial cervicitis in marmosets.

A total of 14 marmosets were inoculated intra-vaginally with Chlamydia trachomatis and the development of genital tract disease was assessed microbiologically, by colposcopic examination of the cervical and vaginal mucosa and by cytological and histological examination of biopsy and autopsy specimens. Eight animals had infections which persisted microbiologically for 2-5 weeks, and six animals, three of which had been inoculated on multiple occasions in a previous study, apparently eliminated their infection within 1 week of inoculation. Colposcopic examination showed that four of the eight infected animals developed acute cervicitis characterized by erythema, occasional slight oedema, and the presence of cloudy or purulent cervical mucus. The other four infected animals showed minimal signs of cervical inflammation. Three of the six animals which rapidly cleared their infections developed slight cervical inflammation characterized by erythema and cloudy cervical mucus during the fortnight after inoculation. Six control animals inoculated with medium displayed minimal cervical changes. The diagnosis of acute cervicitis in the infected animals was confirmed by examination of histological sections and cervical smears, which revealed the presence of polymorphonuclear leucocytes, with lymphocytes occasionally being seen. Although inflammatory changes were occasionally noted in specimens from control animals, the changes were relatively mild and occurred at a later time than those seen in infected animals. Intracytoplasmic chlamydial inclusions in epithelial cells were not detected in any of the specimens studied. Examination of genital tract tissue obtained at autopsy from five inoculated animals generally showed inflammation of the cervix and vagina, but in only one of these animals was there evidence of endometriosis and salpingitis.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1984

Ureaplasmas as a cause of disease in man and animals: fact or fancy?

There is reluctance by some to regard ureaplasmas as a cause of nongonococcal urethritis in men largely because the organisms may also be found in healthy persons. Could they be no more than passengers in disease? A review of past work suggests that this is not likely, a notion supported by the results of more recent studies. In certain other human diseases, such as urethritis and arthritis in hypogammaglobulinemic patients, the pathogenicity of ureaplasmas appears beyond question. In a variety of other conditions, such as the urethral syndrome in women, infertility, various pregnancy-related problems, and respiratory distress in infants, the situation is confused. It is possible that ureaplasmas have some part to play in all these conditions. However, both old and new information indicates that they do not have a major role in most of them, and that assertions to the contrary are fanciful. In the veterinary field, it is easier to come to conclusions about the role of these organisms, although their involvement in genital tract disease is least well validated. Finally, the occurrence of ureaplasmas in a colony of male and female chimpanzees, some with infertility problems, is presented, and the possible value of this situation in attempting to define the role of ureaplasmas in the human condition is mentioned.

Abortion, Spontaneous↗
PubMed1984

Differential characteristics of a small gram-negative anaerobe associated with non-gonococcal urethritis which morphologically resembles Bacteroides ureolyticus.

Strains of a small, Gram-negative anaerobe described as 'NGU-associated' because of its apparent association with non-gonococcal urethritis (NGU), grew synergistically with anaerobic cocci on primary isolation. Subsequently, it was found that the addition of formate-fumarate to the media enhanced their growth. The organisms were asaccharolytic and, unlike most anaerobes, produced oxidase (cytochrome c) and tolerated 5% oxygen when grown in an atmosphere of 2% hydrogen, 7.5% carbon dioxide and 85.5% nitrogen. The strains examined appeared homogeneous culturally, morphologically and biochemically, and had some characteristics in common with Bacteroides ureolyticus (NCTC 10948) and Wolinella succinogenes (ATCC 29543). However, the latter was flagellated and had a DNA G + C content (46-49 mol%) that was different from B. ureolyticus (28 mol%) and the NGU-associated strains (28-30 mol%). These strains and B. ureolyticus shared many properties but electron microscopy of the NGU-associated strains revealed polar pili which were not seen on the strain of B. ureolyticus examined. Other tests which differentiated B. ureolyticus from the NGU-associated strains, being positive only for the latter, were lysine and ornithine decarboxylation, beta-haemolysis and growth in 5% oxygen: those that were negative for the NGU-associated strains were pitting of agar on primary culture and the production of acetate and lactate as metabolic end-products. Despite these differences, the NGU-associated strains may be biotypes or variants of B. ureolyticus, a species which we now consider needs further study and classification.

Bacteroides↗
PubMed1984

Development and evaluation of a selective medium for an anaerobe associated with non-gonococcal urethritis.

The purpose of the study was to develop a selective medium for the isolation of an anaerobe that is associated with non-gonococcal urethritis. This was achieved by determining the sensitivity of 64 strains of the NGU-associated anaerobe to 20 antibiotics and three dyes by the disc-diffusion method. Then the MIC of eight of these antimicrobial agents for ten of the strains was determined by a tube dilution method. The results led to the formulation of a selective agar medium based on the incorporation of polymyxin (0.15 IU/ml), trimethoprim (10 micrograms/ml), vancomycin (10 micrograms/ml) and methyl green (32 micrograms/ml). This medium supported growth of the NGU-associated anaerobe but did not support growth of the other anaerobes tested. The selective nature of the medium made possible the recovery of the NGU-associated anaerobe from 13 of the 25 specimens from men with NGU, compared with isolation from only 8 of these men when using a non-selective medium.

Anti-Bacterial Agents↗
PubMed1984

A study of the susceptibility of three species of primate to vaginal colonization with Gardnerella vaginalis.

In an attempt to develop an animal model of Gardnerella-associated vaginitis, several strains of Gardnerella vaginalis were inoculated into the lower genital tract of female pig-tailed macaques, tamarins and chimpanzees. G. vaginalis was not recovered from either tamarins or chimpanzees, but was recovered from each of 1O pig-tailed macaques inoculated with either of two freshly isolated Gardnerella strains, colonization persisting for 11-39 days. Examination of Gram-stained vaginal smears obtained from infected pig-tailed macaques failed to demonstrate clue cells, a feature which is pathognomonic of Gardnerella-associated vaginitis in humans. Other features characteristic of non-specific vaginitis, namely an increase in vaginal pH, and an increase in the ratio of succinate to lactate (S/L ratio) in vaginal fluid were not found. However, the physiology of the macaque vagina was found to be different from that of the human, the vaginal pH and S/L ratio of uninfected macaques both being higher than that seen in humans. The physiological differences between the macaque and human vagina may be due, in part, to a difference in their anaerobic vaginal flora. While these inter-species differences in vaginal physiology and microbiology limit the relevance of the pig-tailed macaque as a model of Gardnerella-associated vaginitis, the ease with which macaques are colonized with G. vaginalis may prove useful in studying bacterial adhesion and local immunity.

Animals↗
PubMed1984

Reinfection of the mouse genital tract with Chlamydia trachomatis: the relationship of antibody to immunity.

Progesterone-treated CBA mice which had had genital infections with a fast, human strain of Chlamydia trachomatis either 8, 16, 58, or 69 weeks previously were rechallenged through the uterine wall, along with groups of untreated controls. Serum IgG antibody and/or local IgA antibody was measured using a micro-immunofluorescence technique. Although the infection was self-limiting, chlamydiae were cleared significantly more quickly from the previously infected groups than from their controls in all experiments. However, mice which had had a previous infection recently and which had high titres (geometric mean 1: greater than or equal to 2048) of serum IgG antibody and local IgA antibody immediately before rechallenge, were as susceptible as mice which had had a distant past infection and which had much lower titres (geometric mean 1:48) of serum IgG antibody. Thus, some immunity was induced in the mouse model, but pre-existing antibody seemed to be of little importance in this, and did not influence the initial susceptibility to reinfection.

Animals↗