Development and Automation of a Bacterial Biosensor to the Targeting of the Pollutants Toxic Effects by Portable Raman Spectrometer.

Water quality monitoring requires a rapid and sensitive method that can detect multiple hazardous pollutants at trace levels. This study aims to develop a new generation of biosensors using a low-cost fiber-optic Raman device. An automatic measurement system was thus conceived, built and successfully tested with toxic substances of three different types: antibiotics, heavy metals and herbicides. Raman spectroscopy provides a multiparametric view of metabolic responses of biological organisms to these toxic agents through their spectral fingerprints. Spectral analysis identified the most susceptible macromolecules in an E. coli model strain, providing a way to determine specific toxic effects in microorganisms. The automation of Raman analysis reduces the number of spectra required per sample and the measurement time: for four samples, time was cut from 3 h to 35 min by using a multi-well sample holder without intervention from an operator. The correct classifications were, respectively, 99%, 82% and 93% for the different concentrations of norfloxacin, while the results were 85%, 93% and 81% for copper and 92%, 90% and 96% for 3,5-dichlorophenol at the three tested concentrations. The work initiated here advances the technology needed to use Raman spectroscopy coupled with bioassays so that together, they can advance field toxicological testing.

Mid-term clinical results of the cementless R3 cup and Polarstem total hip arthroplasty.

BACKGROUND: There has been a shift from cemented to uncemented hip arthroplasty. One popular uncemented combination is the R3 acetabular cup with Polarstem, having the lowest revision rate in the UK National Joint Registry. However, there are no medium-term clinical outcomes on this combination in the literature. The aim of this study is to review our centre's outcomes with this combination using conventional bearings with a minimum of 7-year follow-up. METHODS: Using our centre's arthroplasty database, we identified all patients that underwent a total hip arthroplasty using these implants from August 2009 to December 2010. One hundred and forty-four procedures were performed. The primary outcome was revision rate, and the secondary outcomes were clinical and radiological evaluation. RESULTS: The mean cohort age at surgery was 68.3 years. There were three revisions, of which only one underwent a cup revision. The mean Oxford Hip Score at 7-year follow-up was 38. Radiological evaluation of both acetabular and stem component did not show any radiolucency at 7-year follow-up. Kaplan-Meier survivorship analysis showed an implant survival rate of 97.69% at 7 years using revision for all causes as endpoint. The risk of revision was 1.47% at 7 years. CONCLUSION: Our revision rates are comparable to the UK's National Joint Registry, with excellent clinical and radiological outcome. Our results correlate with the allocated rating of 7A* by the Orthopaedic Data Evaluation Panel for both R3 acetabular cup and Polarstem.

Screening of metallic pollution in complex environmental samples through a transcriptomic fingerprint method.

Characterizing waste ecotoxicity is laborious because of both the undefined nature of environmental samples and the diversity of contaminants that can be present. With regard to these limitations, traditional approaches do not provide information about the nature of the pollution encountered. To improve such assessments, a fluorescent library of 1870 transcriptomic reporters from Escherichia coli K12 MG1655 was used to report the ecotoxic status of environmental samples. The reliability of the approach was evaluated with 6 metallic pollutants (As, Cu, Cd, Hg, Pb, Zn) used alone and in mixture in pure and complex matrices. A total of 18 synthetic samples were used to characterize the specificity of the resulting metallic contamination fingerprints. Metallic contamination impacted 4.5 to 10.2% of the whole transcriptomic fingerprint of E. coli. The analysis revealed that a subset of 175 transcriptomic reporters is sufficient to characterize metallic contamination, regardless of the nature of the sample. A statistical model distinguished patterns due to metallic contamination and provided information about the level of toxicity with 93 to 98% confidence. The use of the transcriptomic assessment was validated for 17 complex matrices with various toxicities and metal contaminants, such as activated sludge, wastewater effluent, soil, wood and river water. The presence of metals and their associated toxicity, which seems linked to their bioavailabilities, were thereby determined. This method constitutes a possible tool to screen unknown complex samples for their metallic status and identify those for which a deeper characterization must be achieved by the use of traditional biosensors and analytical methods.

Syntheses, crystal structures, transport properties and first-principles electronic structure study of the (tTTF)2X (X=Br, I) low-dimensional antiferromagnets.

An efficient synthetic procedure for the preparation of unsymmetrically substituted tetrathiafulvalene (TTF) donors has been used to obtain the trimethylene-tetrathiafulvalene (tTTF) donor with high purity. Good quality crystals of the two (tTTF)(2)X (X = Br, I) salts have been obtained by electrocrystallization. The two salts are isomorphous and contain tTTF layers which are built from (tTTF)(2) dimeric units. Both systems are low-dimensional antiferromagnets with the highest Néel temperatures for TTF based radical cation salts: ≈ 35 K (Br salt) and ≈43 K (I salt). The resistivity is found to substantially decrease with pressure although both salts still have activated conductivity at 25 kbar. First-principles Density Functional Theory (DFT) calculations have been used to investigate the relative strength of the three different types of magnetic interactions in the tTTF layers as well as the potential magnetic ground states. These calculations successfully predict the nature of the ground state and suggest a possible correlation between structural details and Néel temperatures for the bromine and iodine salts. Remarkably, the calculated antiferromagnetic ground state can be predicted from the nesting properties of the Fermi surface for the hypothetical Pauli paramagnetic metallic state.

Systematic Review With Meta-Analysis: Are Muscle Transfers a Satisfactory Treatment Option to Restore Shoulder Abduction in Delayed Adult Brachial Plexus Injuries?

Brachial plexus injuries usually result in significant upper limb disabilities and shoulder joint instability. Primary nerve reconstruction procedures are more effective if performed within six months from the injury. Secondary procedures, including muscle transfers, are usually indicated for delayed presentation (>6 months) or when the outcomes of primary procedures are unsatisfactory. A comprehensive systematic search of the MEDLINE, EMBASE, AMED, PubMed, and Cochrane databases was conducted in line with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Data, including demographic information, time to surgery, the extent of brachial plexus injury, surgical techniques, follow-up duration, and functional outcomes were collected and tabulated. Meta-analysis was conducted using Review Manager (RevMan) 5.4 software ([Computer program]. Version 5.3. Copenhagen: The Nordic Cochrane Centre, The Cochrane Collaboration, 2014). Seven studies were eligible to be included in this review, with a total of 218 patients. The average patient age was 28.39 ± 3 years, with a mean time to surgery of 29.87 ± 18 months. Forty-six (46) patients (21.10%) were treated as delayed presentation and 172 patients (78.89%) had muscle transfer performed as a secondary procedure. The mean time at follow-up was 18.86 ± 13.5 months. Upper trapezius muscle transfer was the most common transferred muscle (100%) either in isolation (n=159, 72.93%) or in combination with lower trapezius transfer (n=59, 27.06%). The mean preoperative and postoperative shoulder abduction were 12.22 ± 10.09 degrees and 58.36 ± 32.33 degrees, respectively (p < 0.05). Meta-analysis shows a statistically significant difference (CI at 95%, p<0.05) favoring postoperative shoulder abduction. Muscle transfers especially upper trapezius transfer could be a satisfactory secondary procedure to restore shoulder abduction and enhance shoulder joint stability.

Study of structural changes of gluten proteins during bread dough mixing by Raman spectroscopy.

The aim of the present study was to evaluate Raman spectroscopy in determining changes that occur in the structure of gluten proteins induced during bread dough mixing. Raman spectra were measured directly within the dough. Three particular phases of mixing were studied: under-mixing, optimum mixing and over-mixing. A thiol blocking reagent, Tris(2-carboxyethyl)phosphine (TCEP) was then used to reduce disulphide bonds within proteins to confirm the important role of disulphide bridges in gluten network formation. For the control dough, the most important changes occurred during the optimum mixing phase when an increase in intermolecular disulphide bonds, anti-parallel ß-sheet and α-helix structures was observed, combined with the hydrophobic burial of tryptophan and tyrosine residues. The addition of TCEP appeared to effectively reduce the formation of intermolecular disulphide bonds, anti-parallel ß-sheet and α-helix structures and lead to a more disordered secondary protein structure.

Improving the surgical consenting process for patients with acute hip fractures: a pilot quality improvement project.

BACKGROUND: Consenting patients for trauma procedures following hip fracture is a key stage in the treatment pathway from admission to the operating theatre. Errors in this process can result in delayed procedures which may negatively impact patient recovery. The aim of this project was to identify and reduce errors in our consenting process for patients with capacity. METHODS: Consent forms for all adult patients with capacity admitted for surgical repair of traumatic hip fracture were reviewed over a 4-week period. The baseline measurement (n = 24), identified errors in three key process measures: clarity of documentation, failure to record procedure-specific risks and not offering a copy of the consent form to the patient. Pre-printed stickers and targeted teaching were then introduced as quality improvement measures. Their impact was evaluated over subsequent 4-week review of the same patient demographic, with further refinement of these interventions being carried out and re-evaluated for a final cycle. RESULTS: Cycle 1 (n = 26) following targeted teaching demonstrated a reduction in abbreviations from 38 to 20%, while doubling the documentation of discussion of procedure-specific risks from 31 to 72%. More patients were offered a copy of their consent form, rising from 12 to 48%. Cycle 2 (n = 24) saw the introduction of pre-printed "risk of procedure" stickers. Although clarity measures continued to improve, quality of pre-procedure risk documentation remained static while the number of forms being offered to patients fell to 8%. CONCLUSIONS: Our project would suggest that while pre-printed stickers can be useful memory aids, specific teaching on consenting produces the greatest benefit. The usage of such tools should therefore be limited, as adjuncts only to specific training.

Applying Raman spectroscopy to the assessment of the biodegradation of industrial polyurethanes wastes.

Polyether-based polyurethanes (PBP) are extremely problematic polymers due to their long persistence in the environment. Moreover, the assessment of PBP biodegradation remains biased due to the inability of conventional methods to determine how their diverse subunits are degraded. To improve our knowledge of PBP biodegradation, we used Raman spectroscopy to identify patterns of PBP biodegradation. Specifically, PBP biodegradation was assessed using a microbial inoculum isolated from an industrial soil in which polyurethanes have been buried for 40 years. During a 28-day biodegradation assay, the PBP biodegradation level reached 27.5% (w/w), in addition to undergoing profound alteration of the PBP composition as identified by chemical analyses. After microbial degradation, Raman analyses revealed the disappearance of the polymer's amorphous region, which contains a high polyol content, whereas the isocyanate-rich crystalline regions were preserved. The use of Raman spectroscopy appears to be a particularly useful tool to enhance our assessment of polymer biodegradation.