120 research outputs found
Author correction to: Structure and distribution of an unrecognized interstitium in human tissues
© 2018 The Author(s). The Supplementary Figure file that accompanies this Article contains an error in Supplementary Figure S1, where the Small Intestine CD34 panel was duplicated from the Gallbladder CD34 panel. The correct Figure S1 appears below as Figure 1. (Figure Presented)
Green Fluorescent Protein Labeling of Listeria, Salmonella, and Escherichia coli O157:H7 for Safety-Related Studies
Many food safety-related studies require tracking of introduced foodborne pathogens to monitor their fate in complex environments. The green fluorescent protein (GFP) gene (gfp) provides an easily detectable phenotype so has been used to label many microorganisms for ecological studies. The objectives of this study were to label major foodborne pathogens and related bacteria, including Listeria monocytogenes, Listeria innocua, Salmonella, and Escherichia coli O157:H7 strains, with GFP and characterize the labeled strains for stability of the GFP plasmid and the plasmid's effect on bacterial growth. GFP plasmids were introduced into these strains by a CaCl2 procedure, conjugation or electroporation. Stability of the label was determined through sequential propagation of labeled strains in the absence of selective pressure, and rates of plasmid-loss were calculated. Stability of the GFP plasmid varied among the labeled species and strains, with the most stable GFP label observed in E. coli O157:H7. When grown in nonselective media for two consecutive subcultures (ca. 20 generations), the rates of plasmid loss among labeled E. coli O157:H7, Salmonella and Listeria strains ranged from 0%â30%, 15.8%â99.9% and 8.1%â93.4%, respectively. Complete loss (>99.99%) of the plasmid occurred in some labeled strains after five consecutive subcultures in the absence of selective pressure, whereas it remained stable in others. The GFP plasmid had an insignificant effect on growth of most labeled strains. E. coli O157:H7, Salmonella and Listeria strains can be effectively labeled with the GFP plasmid which can be stable in some isolates for many generations without adversely affecting growth rates
Maternal complications following open and fetoscopic fetal surgery: A systematic review and meta-analysis
OBJECTIVE: To establish maternal complication rates for fetoscopic or open fetal surgery. METHODS: We conducted a systematic literature review for studies of fetoscopic or open fetal surgery performed since 1990, recording maternal complications during fetal surgery, the remainder of pregnancy, delivery and after the index pregnancy. RESULTS: One hundred and sixty-six studies were included, reporting outcomes for open fetal (n=1193 patients) and fetoscopic surgery (n=9403 patients). No maternal deaths were reported. The risk of any maternal complication in the index pregnancy was 20.9% (95%CI 15.22-27.13) for open fetal and 6.2% (95%CI 4.93-7.49) for fetoscopic surgery. For severe maternal complications (Grade III to V Clavien-Dindo classification of surgical complications) the risk was 4.5% (95%CI 3.24-5.98) for open fetal and 1.7% (95%CI 1.19-2.20) for fetoscopic surgery. In subsequent pregnancies, open fetal surgery increased the risk of preterm birth but not uterine dehiscence or rupture. Nearly one quarter of reviewed studies (n=175, 23.3%) were excluded for failing to report the presence or absence of maternal complications. CONCLUSIONS: Maternal complications occur in 6.2% fetoscopic and 20.9% open fetal surgeries, with serious maternal complications in 1.7% fetoscopic and 4.5% open procedures. Reporting of maternal complications is variable. To properly quantify maternal risks, outcomes should be reported consistently across all fetal surgery studies
Evaluation of the use of PetrifilmTM EB count plates for the enumeration of Enterobacteriaceae in poultry samples
The limitations of hibonite as a single-mineral oxybarometer for early solar system processes
The relationships between the composition of hibonite with the general formula CaAl12-2x-yMgxTi4 +xTi3 +yO19, the oxidation state of Ti (Ti3 +/ÎŁTi, where ÎŁTi = Ti3 + + Ti4 +), and oxygen fugacity (fO2) were investigated experimentally. It was found that hibonite can be synthesised with a range of Ti3 +/ÎŁTi values at constant fO2 and with a constant Ti3 +/ÎŁTi value for a range of fO2s. It was also found that if hibonite with the formula CaAl12-yTi3 +yO19 (Ti3 +/ÎŁTi = 1) is equilibrated with a melt of CAI composition at fO2s below the iron-wĂŒstite buffer then the resulting hibonite contained Mg, with Mg per formula unit (pfu) ~ 0.8 Ti pfu, and Ti3 +/ÎŁTi ~ 0.2, irrespective of the fO2. These results suggest that the availability of Mg, rather than fO2, is the key factor that determines Ti3 +/ÎŁTi of hibonite. The structures of synthetic samples of hibonite with the general formula CaAl12-2xMgxTi4 +xO19, where 0 †X < 1, were determined by Rietveld refinement of X-ray powder diffraction data. The predominant site occupied by Ti4 + was found to change from M2 to M4 with increasing Ti content. The range of Ti concentrations over which the site occupancy changed corresponds to that observed in meteoritic hibonite. This change in the Ti4 + site produces changes in the Ti K-edge XANES spectra, particularly in the intensity of the pre-edge feature, for constant Ti3 +/ÎŁTi. The observed dependence of the pre-edge on the Ti4 + site was reproduced by ab initio simulations of the XANES spectra. The XANES spectra of natural hibonite with variable Ti content from the Murchison carbonaceous chondrite closely match the spectra of the synthetic samples with similar Ti contents. These differences in the spectra of meteoritic hibonite could be misinterpreted as being due to changes in Ti3 +/ÎŁTi, but are instead due to differences in ÎŁTi, which relate to the petrogenetic history. Crystal chemistry exerts a first order control on the Ti site occupancy and Ti3 +/ÎŁTi value of hibonite. As a result, no simple relationship between Ti3 +/ÎŁTi and fO2 should be expected. It is unlikely that hibonite will be useful as an oxybarometer for solar processes without Ti3 +/ÎŁTi standards that are compositionally matched to the unknown
Percepção sobre a higiene dos manipuladores de alimentos e perfil microbiológico em restaurante universitårio
CaracterĂsticas fĂsico-quĂmicas e microbiolĂłgicas de morango minimamente processado
Survey of verotoxin-producing Escherichia coli and faecal coliforms in beef carcasses destined for export at slaughterhouses in Brazil
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