<Emphasis Type="Italic">Trichomonas vaginalis</Emphasis> harboring <Emphasis Type="Italic">Mycoplasma hominis</Emphasis> increases cytopathogenicity in vitro

The parasite Trichomonas vaginalis causes one of the most common non-viral sexually transmitted infections in humans. Mycoplasmas are frequently found with trichomonads but the consequences of this association are not yet known. In the present study, the effects of T. vaginalis harboring M. hominis on human vaginal epithelial cells and on MDCK cells are described. The results were analyzed by light, scanning and transmission electron microscopy, as well as using cell viability assays. There was an increase in the cytopathic effects on the epithelial cells infected with T. vaginalis associated with M. hominis compared to T. vaginalis alone. The epithelial cells exhibited an increase in the intercellular spaces, a lesser viability, and increased destruction provoked by the infected T. vaginalis. In addition, the trichomonads presented a higher amoeboid transformation rate and an intense phagocytic activity, characteristics of higher virulence behavior.     

细胞培养中支原体污染的去除

在运用细胞培养手段的生物学研究和生物工程产品中，支原体污染仍是一个颇为棘手的问题。１１株人的细胞ＳＰＣ－Ａ１、Ｋ５６２、ＨＵＴ－１０２、ＢＴ－３２５、６Ｔ－ＣＥＭ、ＮＫＭ－４５、ＣＮＥ、ＨＬ－６０、ＱＧＹ－７７０１、ＱＺＧ、人羊膜细胞；３株小鼠细胞Ｐ３８８－１、ＹＡＣ－１、Ｐ８１５；１株绒猴细胞Ｂ９５－８；和一株杂交瘤ＱＫＴ３等，已污染了支原体的细胞经ＭＣ－２１０ １μｇ／ｍｌ处理７天，支原体污染     

Changes in epithelial secretory cells and potentiation of neurogenic inflammation in the trachea of rats with respiratory tract infections

Summary In rats respiratory tract infections due to Sendai virus and coronavirus usually are transient, but they can have long-lasting consequences when accompanied by Mycoplasma pulmonis infections. Morphological alterations in the tracheal epithelium and a potentiation of the inflammatory response evoked by sensory nerve stimulation (neurogenic inflammation) are evident nine weeks after the infections begin, but the extent to which these changes are present at earlier times is not known. In the present study we characterized these abnormalities in the epithelium and determined the extent to which they are present 3 and 6 weeks after the infections begin. We also determined the magnitude of the potentiation of neurogenic inflammation at these times, whether the potentiation can be reversed by glucocorticoids, and whether a proliferation of blood vessels contributes to the abnormally large amount of plasma extravasation associated with this potentiation. To this end, we studied Long-Evans rats that acquired these viral and mycoplasmal infections from other rats. We found that the tracheal epithelium of the infected rats had ten times as many Alcian blue-PAS positive mucous cells as did that of pathogen-free rats; but it contained none of the serous cells typical of pathogen-free rats, so the total number of secretory cells was not increased. In addition, the epithelium of the infected rats had three times the number of ciliated cells and had only a third of the number of globule leukocytes. In response to an injection of capsaicin (150 g/kg i.v.), the tracheas of the infected rats developed an abnormally large amount of extravasation of two tracers Evans blue dye and Monastral blue pigment, and had an abnormally large number of Monastral blue-labeled venules, particularly in regions of mucosa overlying the cartilaginous rings. This abnormally large amount of extravasation was blocked by dexamethasone (1 mg/day i.p. for 5 days). We conclude that M. pulmonis infections, exacerbated at the outset by viral infections, result within three weeks in the transformation of epithelial serous cells into mucous cells, the proliferation of ciliated cells, and the depletion of globule leukocytes. They also cause a proliferation of mediator-sensitive blood vessels in the airway mucosa, which is likely to contribute to the potentiation of neurogenic inflammation that accompanies these infections.Funded in part by National Institutes of Health Pulmonary Program Project Grant HL-24136 from the US Public Health Service. Dr. Huang is the recepient of an award from the National Science Council of the Republic of China     

Ureaplasma urealyticum infection in newborns: Three case reports

We report three newborns with different manifestations ofUreaplasma urealyticum infection; a term newborn with acute neonatal pneumonia and two very low birth weight infants with bronchopulmonary dysplasia and osteomyelitis of the femur, respectively. The association ofU. urealyticum with acute and chronic respiratory disease in term and preterm newborns has recently been reported. Our two cases are similar to other case reports from the literature, but we were unable to find any previous reports of osteomyelitis due toU. urealyticum in the premature babies. Isolation ofU. urealyticum in pure culture from the blood was considered to be related to local infection in all three patients. All patients were cured by erythromycin.     

巢式PCR与免疫组化在检测肾癌组织支原体中的应用

目的:评价巢式PCR和免疫组化技术在检测肾癌组织支原体中的应用和价值。方法:采用支原体通用引物巢式PCR技术和单克隆抗体PD4免疫组化技术,检测95例肾癌组织中支原体DNA和支原体p40蛋白表达。结果:免疫组化检测和巢式PCR检测的阳性检出率分别为64.2%和81.1%,巢式PCR技术检测肾癌组织支原体在灵敏度、特异度、约登指数、阳性预测值和阴性预测值方面均优于免疫组化技术。结论:巢式PCR和免疫组化技术均可作为肾癌组织支原体的检测方法,巢式PCR较免疫组化检测敏感。     

Host-pathogen interactions in mycoplasma pathogenesis: virulence and survival strategies of minimalist prokaryotes

Despite their very small genomes mycoplasmas are successful pathogens of man and a wide range of animal hosts. Because of the lack of effective therapeutics and vaccines, mycoplasma diseases continue to be a significant problem for public health as well as livestock production with major socio-economic consequences worldwide. Recent outbreaks and epidemiological studies predict that the incidence of human and animal mycoplasma diseases might increase which indicates the urgent need to develop new approaches for prevention and therapy. Development of such reagents, however, requires a solid understanding of the molecular biology of mycoplasma infections. Knowledge in this field has considerably increased during the past decade since new techniques have been developed and adapted to mycoplasmas that allow these organisms to be studied at the molecular level. Research on the two human pathogens Mycoplasma pneumoniae and Mycoplasma genitalium of which the genome sequences have recently been completed as well as the substantial number of studies carried out on the AIDS-associated mycoplasmas, Mycoplasma penetrans and Mycoplasma fermentans, has led the way, but a number of animal mycoplasmas are becoming increasingly appreciated as models for the study of the molecular basis of mycoplasma diseases. This review summarizes and highlights some of the recent findings concerning the molecular interactions that occur between pathogenic mycoplasmas and their hosts, both the common strategies as well as some unique approaches evolved by particular mycoplasma pathogens, including adherence to and uptake into non-phagocytic host cells, as well as mechanisms of escaping the host immune system.     

Detection of Chlamydia trachomatis,Ureaplasma urealyticum and Mycoplasma hominis in infertile Bulgarian men with multiplex real‐time polymerase chain reaction

The effect of Chlamydia trachomatis, Ureaplasma urealyticum and Mycoplasma hominis over the sperm quality is still unclear. The aim of this study was to determine their prevalence in infertile Bulgarian men. A total of 281 men were examined by applying mRT‐PCR. The registered prevalence was as follows: C. trachomatis – 13.9%, U. urealyticum – 19.2%, M. hominis – 9.9%. Co‐infection was established in eight swabs. This first in Bulgaria to study for detection of chlamydia and mycoplasmas in infertile men by mRT‐PCR demonstrates higher prevalence of the tested microorganisms in the infertile group toward the control one.     

支原体培养液中抑制HIV—1 RT活性物质的分子性状

对支原体培养液进行的高效液相层析分析的结果显示：具有ＤＮａｓｅ和／或ＲＮａｓｅ活性的两个主要蛋白峰（峰１分子量为６７×１０３～１００×１０３，峰２分子量为１０×１０３～２５×１０３）显示出明显的ＲＴ抑制活性。这一结果说明支原体培养液的ＲＴ活性抑制作用来自于培养液中有ＤＮａｓｅ活性和ＲＮａｓｅ活性的部分，对抑制ＨＩＶ－１活性可能有一定相关。     

支原体对宿主细胞的免疫逃逸机制研究进展

支原体是能在无生命培养基中生长繁殖的最小原核细胞型微生物,其种属较多,可广泛寄生于人体、哺乳动物、鸟类及植物中,有很强的致病性。支原体具有独特的生物学结构和功能,其具体的致病机制尚不清楚。近年来研究表明,支原体能在宿主体内的持续性感染是其致病的主要原因。在与宿主的长期共同进化过程中,支原体形成了多种逃逸宿主免疫反应的生存方式,以逃避宿主的免疫应答。     

Towards a genome based taxonomy of Mycoplasmas

Mycoplasmas are Gram-positive wall-less bacteria with a wide environmental and host distribution, causing disease in man and in (wild and farmed) animals. The aim of this study was to analyze the usefulness of a genomic taxonomic approach in Mycoplasma systematics. Multilocus Sequence Analysis (MLSA), average amino acid identity (AAI), and Karlin genomic signature allowed a clear identification of species. For instance, Mycoplasma pneumoniae and Mycoplasma genitalium had only 71% MLSA similarity, 67% AAI, and 88 for Karlin genomic signature. Codon usage (Nc) of the phylogenetically distantly related species Mycoplasma conjunctivae and Mycoplasma gallisepticum was identical, in spite of clear differences in MLSA, AAI, and Karlin, suggesting that these two species were subjected to convergent adaptation due to similar environmental conditions. We suggest that a Mycoplasma species may be better defined based on genomic features. In our hands, a Mycoplasma species is defined as a group of strains that share ?97% DNA identity in MLSA, ?93.9% AAI and ?8 in Karlin genomic signature. This new definition may be useful to advance the taxonomy of Mycoplasmas.