Evaluation of sound levels in elective orthopaedic theatres during primary hip and knee arthroplasty.

BACKGROUND: Orthopaedic surgery involves tools which could cause noise-induced hearing loss in theatre staff. Threshold levels for occupational noise exposure have been developed in the U.K., above which action is required to reduce exposure. The aims of our study were to determine whether equivalent continuous sound pressure levels during elective arthroplasty can be measured using readily available materials, and to assess whether noise exposure levels stand within acceptable occupational noise exposure levels. MATERIALS AND METHODS: Sound pressure levels of orthopaedic saws were recorded using the MicW i436 connected to an iPhone 4S and the iOS SoundMeter application, and using a professional sound meter. Equivalent sound pressure levels were recorded for total hip replacement (THR) and total knee replacement (TKR) using the MicW i436 SoundMeter application. Data obtained was then used to calculate a "worst case" daily exposure value to assess if sound levels were compliant with U.K. RESULTS: Sound pressure levels recorded using the MicW i436 and Soundmeter application were accurate compared to professional soundmeter readings. THR showed equivalent sound pressure levels (LAeq) of 77 dBA and TKR showed a LAeq of 80 db. Calculated "worst case" scenarios for daily noise exposure using these values did not meet the lower exposure action values set out by U.K. CONCLUSIONS: It is possible to accurately measure continuous sound pressure levels during elective orthopaedic surgery using readily available materials. Noise exposure values during TKR meet lower exposure action values, and when "worst case" daily exposure levels are calculated this level is still lower than the threshold.

Anatomical study of the human sacral hiatus and implications for successful caudal epidural injection.

BACKGROUND: Caudal epidural injection (CEI) is a commonly used procedure to treat back and leg pain secondary to nerve root irritation, predominantly in the context of spinal canal stenosis. Key to a successful outcome is correct needle placement. Although fluoroscopic guidance confirms accurate needle placement, it does not help in determining the starting point, which can lead to multiple needle insertions. OBJECTIVE: This study aimed to determine the variability in size and position of the sacral hiatus and to identify reproducible surface landmarks to locate its position. METHODS AND STUDY DESIGN: 250 human sacral bones were examined, measuring morphology and structure. Vernier callipers accurate to 0.1 mm were used for measurements. Results were analysed using SPSS statistical software. RESULTS: Two specimens were excluded due to agenesis of the hiatus (0.8%). Of the remaining 248 specimens, it was found that the mean internal diameter of the sacral hiatus was 5.12 mm (SD 1.61). The position of the hiatus was variable but was most commonly found at the level of the fourth sacral vertebrae (62.9%, n = 156). Mean distance between the two superolateral sacral prominences was 64.15 mm (SD 6.5) and between superolateral sacral prominences (left and right) and apex of the hiatus were 63.21 mm (SD 10.9) and 63.34 mm (SD 10.87) respectively. CONCLUSION: Although there is a clear anatomical variance in the position and size of the sacral hiatus, this study suggests that surface anatomy landmarks can be used to form an equilateral triangle of which the inferior apex should correspond to the sacral hiatus. Knowledge of this surface anatomy may assist the correct location of the sacral hiatus and hence subsequently improve the efficacy of CEI.

Antibody-Binding, Antifouling Surface Coatings Based on Recombinant Expression of Zwitterionic EK Peptides.

Development of antifouling films which selectively capture or target proteins of interest is essential for controlling interactions at the "bio/nano" interface. However, in order to synthesize biofunctional films from synthetic polymers that incorporate chemical "motifs" for surface immobilization, antifouling, and oriented biomolecule attachment, multiple reaction steps need to be carried out at the solid/liquid interface. EKx is a zwitterionic peptide that has previously been shown to have excellent antifouling properties. In this study, we recombinantly expressed EKx peptides and genetically encoded both surface attachment and antibody-binding motifs, before characterizing the resultant biopolymers by traditional methods. These peptides were then immobilized to organosilica nanoparticles for binding IgG, and subsequently capturing dengue NS1 as a model antigen from serum-containing solution. We found that a mixed layer of a short peptide (4.9 kDa) "backfilled" with a longer peptide terminated with an IgG-binding Z-domain (18 kDa) demonstrated selective capture of dengue NS1 protein down to ∼10 ng mL-1 in either PBS or 20% serum.

Open release versus radiofrequency microtenotomy in the treatment of lateral epicondylitis: a prospective randomized controlled trial.

BACKGROUND: Optimal surgical treatment of lateral epicondylitis remains uncertain. Recently, radiofrequency microtenotomy (RFMT) has been proposed as a suitable treatment. We compared RFMT with standard open release (OR) in this prospective randomized controlled trial. METHODS: In total, 41 patients with symptoms for at least 6 months were randomized into two groups: 23 patients had RFMT and 18 had OR. Two patients from RFMT withdrew. Each patient underwent Numerical Rating Scale (NRS) pain score, grip strength and Disabilities of the Arm, Shoulder and Hand (DASH) scores pre-operatively and at 6 weeks. Pain and DASH scores were repeated at 6 months and 12 months. RESULTS: NRS pain scores improved by 4.8 points for RFMT and by 3.9 points for OR. There was a significant improvement in both groups from pre-operative scores, although there was no statistically significant difference between the groups at 1 year. Grip strength improved by 31% in the RFMT group compared to 38% in OR. There was no significant difference between the initial and 6 weeks scores or between treatments. At 1 year, DASH was 39.8 points for RFMT and 24.4 points for OR. There was a significant improvement in both groups from pre-operative scores, although there was no statistically significant difference between the groups at 1 year. CONCLUSIONS: Both groups showed significant improvements and similar benefit to the patient. The results of the present study do not show any benefit of RFMT over the standard OR. As a result of the extra expense of RFMT, we therefore recommend that OR is offered as the standard surgical management.

Evaluation of three adjuvants with respect to both adverse effects and the efficacy of antibody production to the Bm86 protein.

Cattle tick infestations remain an important burden for farmers in tropical area like in New Caledonia. With the development of acaricide resistance, tick vaccines should be an attractive alternative to control ticks but their efficacy needs to be improved. In this study three adjuvants were studied in an experimental tick vaccine with a Bm86 protein to assess their performance in terms of antibody productions and adverse reactions following vaccinations. The water-in-oil adjuvant ISA 61 VG led to higher antibody titers compared to a water-in-oil-in-water adjuvant ISA 201 VG and an aqueous polymeric adjuvant Montanide Gel 01. Vaccinations with these three adjuvants did not produce severe general reaction but an increase in skin thickness was observed especially with both oil-based emulsions. These results indicated that the water-in-oil adjuvant is the most interesting to use for this vaccine but local adverse reactions remain an issue.

Towards an Open Infrastructure for Relating Scholarly Assets.

Discovery of useful relationships between scholarly assets on the web is challenging, both in terms generating the right metadata around the assets, and in connecting all relevant digital entities in chain of provenance accessible to the whole community. This paper reports the development of a framework and tools enabling scholarly asset relationships to be expressed in a standard and open way, illustrated with use-cases of discovering new knowledge across cohort studies. The framework uses Research Objects for aggregation, distributed databases for storage, and distributed ledgers for provenance. Our proposal avoids management by a single central platform or organization, instead leveraging the use of existing resources and platforms across natural partnerships. Our proposed infrastructure will support a wide range of users from system administrators to researchers.

Selective Substrates and Inhibitors for Kallikrein-Related Peptidase 7 (KLK7) Shed Light on KLK Proteolytic Activity in the Stratum Corneum.

Proteases have pivotal roles in the skin's outermost layer, the epidermis. In the stratum corneum, serine proteases from the kallikrein-related peptidase (KLK) family have been implicated in several key homeostatic processes, including desquamation. However, the precise contribution of specific KLKs to each process remains unclear. To address this, we used a chemical biology approach and designed selective substrates and inhibitors for KLK7, the most abundant KLK protease in the stratum corneum. The resulting KLK7 inhibitor is the most potent inhibitor of this protease reported to date (Ki = 140 pM), and displays at least 1,000-fold selectivity over several proteases that are related by function (KLK5 and KLK14) or specificity (chymotrypsin). We then used substrates and inhibitors for KLK5, KLK7, and KLK14 to explore the activity of each protease in the stratum corneum using casein zymography and an ex vivo desquamation assay. These experiments provide the most detailed assessment of each KLK's contribution to corneocyte shedding in the plantar stratum corneum, revealing that inhibition of KLK7 alone is sufficient to block shedding, whereas KLK5 is also a major contributor. Collectively, these findings unveil chemical tools for studying KLK activity and demonstrate their potential for characterizing KLK biological functions in epidermal homeostasis.

An eHealth Approach to Reporting Allergic Reactions to Food and Closing the Knowledge Gap.

There is an important knowledge gap in food allergy management in understanding the factors that determine allergic reactions to food, in gathering objective reports of reactions in real time, and in accessing patients' reaction-histories during consultations. We investigate how eHealth methods can close this knowledge gap. We report experiences with an online tool for reporting allergic reactions that we have developed as a web application. This application has been successfully validated by participants from Ireland and the UK, and is currently being used in a pilot where participants report allergic reactions in near-real time.

Mechanism-based selection of a potent kallikrein-related peptidase 7 inhibitor from a versatile library based on the sunflower trypsin inhibitor SFTI-1.

Potent and specific enzyme inhibition is a key goal in the development of therapeutic inhibitors targeting proteolytic activity. The backbone-cyclized peptide, Sunflower Trypsin Inhibitor (SFTI-1) affords a scaffold that can be engineered to achieve both these aims. SFTI-1's mechanism of inhibition is unusual in that it shows fast-on/slow-off kinetics driven by cleavage and religation of a scissile bond. This phenomenon was used to select a nanomolar inhibitor of kallikrein-related peptidase 7 (KLK7) from a versatile library of SFTI variants with diversity tailored to exploit distinctive surfaces present in the active site of serine proteases. Inhibitor selection was achieved through the use of size exclusion chromatography to separate protease/inhibitor complexes from unbound inhibitors followed by inhibitor identification according to molecular mass ascertained by mass spectrometry. This approach identified a single dominant inhibitor species with molecular weight of 1562.4 Da, which is consistent with the SFTI variant SFTI-WCTF. Once synthesized individually this inhibitor showed an IC50 of 173.9 ± 7.6 nM against chromogenic substrates and could block protein proteolysis. Molecular modeling analysis suggested that selection of SFTI-WCTF was driven by specific aromatic interactions and stabilized by an enhanced internal hydrogen bonding network. This approach provides a robust and rapid route to inhibitor selection and design.

Mechanism-based selection of a potent kallikrein-related peptidase 7 inhibitor from a versatile library based on the sunflower trypsin inhibitor SFTI-1.

Potent and specific enzyme inhibition is a key goal in development of therapeutic inhibitors targeting proteolytic activity. The backbone-cyclised peptide, Sunflower Trypsin Inhibitor (SFTI-1) affords a scaffold that can be engineered to achieve both these aims. SFTI-1's mechanism of inhibition is unusual in that it shows fast-on/slow-off kinetics driven by cleavage and religation of a scissile bond. This phenomenon was used to select a nanomolar inhibitor of kallikrein related peptidase 7 (KLK7) from a versatile library of SFTI variants with diversity tailored to exploit distinctive surfaces present in the active site of serine proteases. Inhibitor selection was achieved through use of size exclusion chromatography to separate protease/inhibitor complexes from unbound inhibitors followed by inhibitor identification according to molecular mass ascertained by mass spectrometry. This approach identified a single dominant inhibitor species with molecular weight of 1562.4 Da, which is consistent with the SFTI variant SFTI-WCTF. Once synthesised individually this inhibitor showed an IC50 of 173.9±7.6 nM against chromogenic substrates and could block protein proteolysis. Molecular modelling analysis suggested that selection of SFTI-WCTF was driven by specific aromatic interactions and stabilised by an enhanced internal hydrogen bonding network. This approach provides a robust and rapid route to inhibitor selection and design. © 2013 Wiley Periodicals, Inc. Biopolymers, 2013.