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91.

Objective

To compare the inflammatory response preserved ex vivo by decidual cells isolated from women who experienced preterm labor with and without subclinical intrauterine infection.

Methods

Fetal membranes were obtained after cesarean section from 35 women who delivered before 37 weeks of gestation following spontaneous preterm labor, with no clinical evidence of intrauterine infection. Decidua was microbiologically tested and cultured. Concentrations of anti-inflammatory cytokines (IL-2, IL-4, IL-10), pro-inflammatory cytokines (IL-6, IL-8, IL-1β and TNF-α), and matrix metalloproteinases (MMP-1, MMP-2, MMP-3, MMP-7, MMP-8, MMP-9) were measured in the supernatants using Bio-Plex, and prostaglandin E2 (PGE2) was measured by enzyme immunoassay.

Results

Subclinical infection was confirmed in 10 women (28.5%). Microorganisms isolated were Ureaplasma urealyticum (4), group B streptococci (3), Gardnerella vaginalis (1), and Escherichia coli (2). We found a significant increase of pro-inflammatory cytokines and a significant decrease of anti-inflammatory cytokines in supernatants from decidual cells obtained from women with preterm labor and subclinical intrauterine infection compared to women without infection. Secretion of MMP-1, MMP-8, MMP-9 and PGE2 was significantly higher in infected women. Secretion of IL-8 by decidual cells from infected women persisted upon repeated in vitro culture passages.

Conclusions

Almost 30% of idiopathic preterm labor cases were associated with subclinical intrauterine infection, and decidual cells isolated from these cases preserved an ex vivo inflammatory status after in vivo bacterial exposure.  相似文献   
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EagI and NotI linking libraries were prepared in the lambda vector, EMBL5, from the mouse-human somatic cell hybrid 1W1LA4.9, which contains human chromosomes 11 and Xp as the only human component. Individual clones containing human DNA were isolated by their ability to hybridise with total human DNA and digested with SalI and EcoRI to identify the human insert size and single-copy fragments. The mean (± SD) insert sizes of the EagI and NotI clones were 18.3 ± 3.2 kb and 16.6 ± 3.6 kb, respectively. Regional localisation of 66 clones (52 EagI, 14 NotI) was achieved using a panel of 20 somatic cell hybrids that contained different overlapping deletions of chromosomes 11 or Xp. Thirty-nine clones (36 EagI, 3 NotI) were localised to chromosome 11; 17 of these were clustered in 11q13 and another nine were clustered in 11q14–q23.1. Twenty-seven clones (16 EagI, 11 NotI) were localised to Xp and 10 of these were clustered in Xp11. The 66 clones were assessed for seven different microsatellite repetitive sequences; restriction fragment length polymorphisms for five clones from 11q13 were also identified. These EagI and NotI clones, which supplement those previously mapped to chromosome 11 and Xp, should facilitate the generation of more detailed maps and the identification of genes that are associated with CpG-rich islands. Received: 27 December 1995 / Revised: 30 January 1996  相似文献   
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The branched M33 antimicrobial peptide was previously shown to be very active against Gram-negative bacterial pathogens, including multidrug-resistant strains. In an attempt to produce back-up molecules, we synthesized an M33 peptide isomer consisting of D-aminoacids (M33-D). This isomeric version showed 4 to 16-fold higher activity against Gram-positive pathogens, including Staphylococcus aureus and Staphylococcus epidermidis, than the original peptide, while retaining strong activity against Gram-negative bacteria. The antimicrobial activity of both peptides was influenced by their differential sensitivity to bacterial proteases. The better activity shown by M33-D against S. aureus compared to M33-L was confirmed in biofilm eradication experiments where M33-L showed 12% activity with respect to M33-D, and in vivo models where Balb-c mice infected with S. aureus showed 100% and 0% survival when treated with M33-D and M33-L, respectively. M33-D appears to be an interesting candidate for the development of novel broad-spectrum antimicrobials active against bacterial pathogens of clinical importance.  相似文献   
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This study aimed to determine the role of influenza-like illness (ILI) surveillance conducted on Leyte Island, the Philippines, including involvement of other respiratory viruses, from 2010 to 2013. ILI surveillance was conducted from January 2010 to March 2013 with 3 sentinel sites located in Tacloban city, Palo and Tanauan of Leyte Island. ILI was defined as fever ≥38°C or feverish feeling and either cough or running nose in a patient of any age. Influenza virus and other 5 respiratory viruses were searched. A total of 5,550 ILI cases visited the 3 sites and specimens were collected from 2,031 (36.6%) cases. Among the cases sampled, 1,637 (75.6%) were children aged <5 years. 874 (43.0%) cases were positive for at least one of the respiratory viruses tested. Influenza virus and respiratory syncytial virus (RSV) were predominantly detected (both were 25.7%) followed by human rhinovirus (HRV) (17.5%). The age distributions were significantly different between those who were positive for influenza, HRV, and RSV. ILI cases were reported throughout the year and influenza virus was co-detected with those viruses on approximately half of the weeks of study period (RSV in 60.5% and HRV 47.4%). In terms of clinical manifestations, only the rates of headache and sore throat were significantly higher in influenza positive cases than cases positive to other viruses. In conclusion, syndromic ILI surveillance in this area is difficult to detect the start of influenza epidemic without laboratory confirmation which requires huge resources. Age was an important factor that affected positive rates of influenza and other respiratory viruses. Involvement of older age children may be useful to detect influenza more effectively.  相似文献   
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A trypsin and chymotrypsin inhibitor was partially purified from Bauhenia purpurea seeds and separated from a second inhibitor by Ecteola cellulose chromatography. The factor inhibited bovine trypsin and chymotrypsin as well as pronase trypsin and elastase. It formed a complex with trypsin and with chymotrypsin, but a ternary complex could not be detected. Differences were detected in the effect on trypsin and on chymotrypsin, although one enzyme interfered with the inhibition of the other. The results obtained point to two active centers on the inhibitor for the trypsin and chymotrypsin inhibition such that the one cannot complex with the inhibitor after this inhibitor had complexed with the other.  相似文献   
100.
The ability of the carcinogen, N-acetoxy-2-acetylaminofluorene (N-AcO-AAF), to induce mutations to azaguanine resistance in diploid human cells was quantitatively investigated and shown to be dose-dependent. The 8-azaguanine (AG) resistance was shown to be heritable in the absence of mutagen or selective agent and the cells of the mutant clones were shown to retain normal sensitivity to N-AcO-AAF.  相似文献   
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