GC×GC Quantification of Priority and Emerging Nonpolar Halogenated Micropollutants in All Types of Wastewater Matrices: Analysis Methodology, Chemical Occurrence, and Partitioning

We report the development and validation of a method to detect and quantify diverse nonpolar halogenated micropollutants in wastewater treatment plant (WWTP) influent, effluent, primary sludge, and secondary sludge matrices (including both the liquid and particle phases) by comprehensive two-dimensional gas chromatography (GC×GC) coupled to micro- electron capture detector (μECD). The 59 target analytes included toxaphenes, polychlorinated naphthalenes, organochlorine pesticides, polychlorinated biphenyls, polybrominated diphenyl ethers, and emerging persistent and bioaccumulative chemicals. The method is robust for a wide range of nonpolar halogenated micropollutants in all matrices. For most analytes, recoveries fell between 70% and 130% in all matrix types. GC×GC-μECD detections of several target analytes were confirmed qualitatively by further analysis with GC×GC coupled to electron capture negative chemical ionization-time-of-flight mass spectrometry (ENCI-TOFMS). We then quantified the concentrations and apparent organic solid-water partition coefficients (Kp) of target micropollutants in samples from a municipal WWTP in Switzerland. Several analyzed pollutants exhibited a high frequency of occurrence in WWTP stream samples, including octachloronaphthalene, PCB-44, PCB-52, PCB-153, PCB-180, several organochlorine pesticides, PBDE-10, PBDE-28, PBDE-116, musk tibetene, and pentachloronitrobenzene. Our results suggest that sorption to dissolved organic carbon (DOC) can contribute substantially to the apparent solids-liquid distribution of hydrophobic micropollutants in WWTP streams.

A comparative assessment of small-head metal-on-metal and ceramic-on-polyethylene total hip replacement

Large-head metal-on-metal (MoM) total hip replacements (THR) have given rise to concern. Comparative studies of small-head MoM THRs over a longer follow-up period are lacking. Our objective was to compare the incidence of complications such as infection, dislocation, revision, adverse local tissue reactions, mortality and radiological and clinical outcomes in small-head (28 mm) MoM and ceramic-on-polyethylene (CoP) THRs up to 12 years post-operatively. A prospective cohort study included 3341 THRs in 2714 patients. The mean age was 69.1 years (range 24 to 98) and 1848 (55.3%) were performed in women, with a mean follow-up of 115 months (18 to 201). There were 883 MoM and 2458 CoP bearings. Crude incidence rates (cases/1000 person-years) were: infection 1.3 vs 0.8; dislocation 3.3 vs 3.1 and all-cause revision 4.3 vs 2.2, respectively. There was a significantly higher revision rate after ten years (adjusted hazard ratio 9.4; 95% CI 2.6 to 33.6) in the MoM group, and ten of 26 patients presented with an adverse local tissue reaction at revision. No differences in mortality, osteolysis or clinical outcome were seen. In conclusion, we found similar results for small-head MoM and CoP bearings up to ten years post-operatively, but after ten years MoM THRs had a higher risk of all-cause revision. Furthermore, the presence of an adverse response to metal debris seen in the small-head MOM group at revision is a cause for concern.

[Accidental intravenous injection of potassium chloride: analysis of contributing factors and barriers to risk reduction]

Errors linked to injectable potassium chloride (KCl) have been the cause of deaths which have occurred for many years. Following an accidental direct intravenous injection of KCl of no clinical consequence for the patient, we have analyzed the contributive factors, established an action plan to prevent this risk and finally assessed its impact. Among the causes leading to medication errors, we have identified those linked to the handling of the drugs by nurses, the team, the work conditions, the organization, the institutional context and finally to the drug itself. The risk reduction procedure involved a withdrawal of injectable KCI ampoules from wards, possible in 52% of the care units, a reorganization of storage for the others. The subsequent monitoring of floorstocks revealed that these measures were insufficient and that the risks prevailed due to the presence of KCI ampoules in drawers assigned to other ionic solutions. A study carried out among the medical and nursing personnel revealed that 61.2% of the doctors thought that the risk existed in their ward and 68% of the nurses considered themselves to be exposed to the risk of a medication error. The drug supply chain of our institution, as in numerous others, is not safe. Hospitals are not yet organized adequately to prevent the occurrence of such an error. The comparison with foreign organizations of drug dispensation allows us to think that the improvement and professionalization of the drug supply chain will both be assets in the prevention of such medication errors.

Sequence-specific high mobility group box factors recognize 10-12-base pair minor groove motifs

Sequence-specific high mobility group (HMG) box factors bind and bend DNA via interactions in the minor groove. Three-dimensional NMR analyses have provided the structural basis for this interaction. The cognate HMG domain DNA motif is generally believed to span 6-8 bases. However, alignment of promoter elements controlled by the yeast genes ste11 and Rox1 has indicated strict conservation of a larger DNA motif. By site selection, we identify a highly specific 12-base pair motif for Ste11, AGAACAAAGAAA. Similarly, we show that Tcf1, MatMc, and Sox4 bind unique, highly specific DNA motifs of 12, 12, and 10 base pairs, respectively. Footprinting with a deletion mutant of Ste11 reveals a novel interaction between the 3' base pairs of the extended DNA motif and amino acids C-terminal to the HMG domain. The sequence-specific interaction of Ste11 with these 3' base pairs contributes significantly to binding and bending of the DNA motif.