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There is a growing effort to develop implantable bionics for restoring eye closure in paralytic lagophthalmos. Knowledge of the natural eyelid attachments is important for active implants that mobilise these attachments or replace them with a sling. Whitnall's tubercle (WT) is traditionally used to identify lateral canthal attachments; however, it is not always present. This study seeks an alternative means of identifying the insertion of the lateral canthus to aid the application of bionic implants.Complete CT head scans of patients in the Sydney Head and Neck Cancer Institute database were retrieved for analysis. The CT scans were segmented using bone and soft-tissue thresholding and then reconstructed. The location of WT and the lateral canthal insertion were recorded and their relation to key anatomical landmarks assessed.Ninety orbits from 45 complete head scans were analysed. WT could be identified bilaterally in 18/45 (40%) samples. The average distance from WT to zygomaticofrontal suture and to lateral orbital margin was 10.8 ± 0.4 mm and 4.4 ± 0.2 mm, respectively. The average height of the lateral canthal insertion from the Jugale point was 13.9 ± 1.8 mm. On regression analysis, the height of lateral canthal insertion was strongly predicted by the height of lateral orbital wall as the determined by the maximum distance of the ZFS from the Jugale point (p = 0.001).In the absence of WT, the height of the lateral orbital wall can be reliability used to localise the insertion site of the lateral canthus.

The fibula free flap (FFF) has been extensively used to repair large segmental bone defects in the maxillofacial region. The reconstruction plate plays a key role in maintaining stability and load-sharing while the fibula unites with adjacent bone in the course of healing and remodeling. However, not all fibula flaps would fully unite, and fatigue of prosthetic devices has been recognized as one major concern for long-term load-bearing applications. This study aims to develop a numerical approach for predicting the fatigue life of the reconstruction plate by taking into account the effect of ongoing bone remodeling.The patient-specific mandible reconstruction with a prosthetic system is studied in this work. The 3D finite element model with heterogeneous material properties obtained from clinical computerized tomography (CT) data is developed for bone, and eXtended Finite Element Method (XFEM) is adopted for the fatigue analysis of the plate. During the remodeling process, the changing apparent density and Young's modulus of bone are simulated in a step-wise fashion on the basis of Wolff's law, which is correlated with the specific clinical follow-up. The maximum biting forces were considered as the driving force on the bone remodeling, which are measured clinically at different time points (4, 16 and 28 months) after reconstruction surgery.Under various occlusal loadings, the interaction between fatigue crack growth and bone remodeling is investigated to gain new insights for the future design of prosthetic devices. The simulation results reveal that appropriate remodeling of grafted bone could extend the fatigue life of fixation plates in a positive way. On the other hand, the rising occlusal load associated with healing and remodeling could lead to fatigue fracture of fixation plate and potentially cause severe bone resorption.This study proposes an effective approach for more realistically predicting fatigue life of prosthetic devices subject to a tissue remodeling condition in-silico. It is anticipated to provide a guideline for deriving an optimal design of patient-specific prosthetic devices to better ensure longevity.

Phosphoinositides in primary mammalian tissue are highly enriched in a stearoyl/arachidonyl (C38:4) diacylgycerol backbone. However, mammalian cells grown in culture typically contain more diverse molecular species of phosphoinositides, characterised by a reduction in arachidonyl content in the sn-2 position. We have analysed the phosphoinositide species in MCF10a cells grown in culture by mass spectrometry. Under either serum or serum starved conditions the most abundant species of PI, PIP, PIP2 and PIP3 had masses which corresponded to C36:2, C38:4, C38:3, C38:2 and C36:1 diacylglycerol backbones and the relative proportions of each molecular species were broadly similar between each phosphoinositide class (approx. 50%, 25%, 10%, 10% and 10% respectively, for the species listed above). Supplementing the culture medium with BSA-loaded arachidonic acid promoted a rapid increase in the proportion of the C38:4 species in all phosphoinositide classes (from approx. 25%–60% of total species within 24 h), but the total amount of all combined species for each class remained remarkably constant. Stimulation of cells, cultured in either normal or arachidonate-enriched conditions, with 2 ng/ml EGF for 90 s caused substantial activation of Class I PI3K and accumulation of PIP3. Despite the increased proportion of C38:4 PIP3 under the arachidonate-supplemented conditions, the total amount of all combined PIP3 species accumulating in response to EGF was the same, with or without arachidonate supplementation; there were however small but significant preferences for the conversion of some PIP2 species to PIP3, with the polyunsaturated C38:4 and C38:3 species being more favoured over other species. These results suggest the enzymes which interconvert phosphoinositides are able to act on several different molecular species and homoeostatic mechanisms are in place to deliver similar phosphoinositide pool sizes under quite different conditions of arachidonate availability. They also suggest enzymes regulating PIP3 levels downstream of growth factor stimulation (i.e. PI3Ks and PIP3-phosphatases) show some acyl selectivity and further work should be directed at assessing whether different acyl species of PIP3 exhibit differing signalling potential.

We assessed the habitat use patterns of the Amargosa vole Microtus californicus scirpensis , an endangered rodent endemic to wetland vegetation along a 3.5 km stretch of the Amargosa River in the Mojave Desert, USA. Our goals were to: (1) quantify the vole’s abundance, occupancy rates and habitat selection patterns along gradients of vegetation cover and spatial scale; (2) identify the processes that likely had the greatest influence on its habitat selection patterns. We trapped voles monthly in six 1 ha grids from January to May 2012 and measured habitat structure at subgrid ( 225 m 2 ) and trap ( 1 m 2 ) scales in winter and spring seasons. Regardless of scale, analyses of density, occupancy and vegetation structure consistently indicated that voles occurred in patches of bulrush ( Schoenoplectus americanus ; Cyperaceae) where cover > 50 % . The majority of evidence indicates the vole’s habitat selectivity is likely driven by bulrush providing protection from intense predation. However, a combination of selective habitat use and limited movement resulted in a high proportion of apparently suitable bulrush patches being unoccupied. This suggests the Amargosa vole’s habitat selection behavior confers individual benefits but may not allow the overall population to persist in a changing environment.

Purpose: The purpose of this study was to evaluate the biomechanical properties of a method of repair using bone tunnels with multiple high-strength nonabsorbable sutures and one knotless suture anchor compared with the standard transosseous technique for repair of the distal triceps. Methods: The triceps tendon footprint was measured in 18 cadaveric elbows (9 matched pairs), and a distal tendon rupture was created. Eighteen elbows (9 matched pairs) were randomly assigned to one of 2 repair groups: transosseous cruciate repair group or knotless anatomic footprint repair group. Cyclic loading was performed for a total of 1,500 cycles and displacement was measured. Data for load at yield and peak load were obtained. Results: The average bony footprint of the triceps tendon was 466 mm 2 . Cyclic loading of tendons from the 2 repair types showed that the knotless anatomic footprint repair produced less displacement when compared with the transosseous cruciate repair (P < .05). Load at yield and peak load were also greater in the knotless anatomic footprint repair group (P < .05). Conclusions: Distal triceps knotless anatomic footprint repair in a cadaveric model had a significantly higher load and cycle to failure when compared with the traditional transosseous cruciate repair and produced less repair site motion. Clinical Relevance: The increased biomechanical strength and resistance to displacement at the tendon-bone interface may lead to improved clinical outcomes with the knotless anatomic footprint repair technique and warrants further clinical study.

The phosphoinositide family of phospholipids, defined here as PtdIns, PtdIns3P, PtdIns4P, PtdIns5P, PtdIns(3,4)P2, PtdIns(3,5)P2, PtdIns(4,5)P2 and PtdIns(3,4,5)P3, play pivotal roles in organising the location and activity of many different proteins acting on biological membranes, including those involved in vesicle and protein trafficking through the endolysosomal system and receptor signal transduction at the plasma membrane. Accurate measurement of the cellular levels of these lipids, particularly the more highly phosphorylated species, is hampered by their high polarity and low cellular concentrations. Recently, much progress has been made in using mass spectrometry to measure many different lipid classes in parallel, an approach generally referred to as ‘lipidomics’. Unfortunately, the acidic nature of highly phosphorylated phosphoinositides makes them difficult to measure using these methods, because they yield low levels of useful ions; this is particularly the case with PtdIns(3,4,5)P3. We have solved some of these problems by methylating the phosphate groups of these lipids with TMS-diazomethane and describe a simple, integrated approach to measuring PtdIns, PtdInsP, PtdInsP2 and PtdInsP3 classes of lipids, in parallel with other phospholipid species, in cell and tissue extracts. This methodology is sensitive, accurate and robust, and also yields fatty-acyl compositions, suggesting it can be used to further our understanding of both the normal and pathophysiological roles of these important lipids.

NAMPT may represent a novel target for drug discovery in various therapeutic areas, including oncology and inflammation. Additionally, recent work has suggested that targeting NAMPT has potential in treating axon degeneration. In this work, publicly available X-ray co-crystal structures of NAMPT and the structures of two known NAMPT inhibitors were used as the basis for a structure- and ligand-based virtual screening campaign. From this, two novel series of NAMPT inhibitors were identified, one of which showed a statistically significant protective effect when tested in a cellular model of axon degeneration.

The pro-apoptotic BH3 only protein BIM(EL) is phosphorylated by ERK1/2 and this targets it for proteasome-dependent degradation. A recent study has shown that ERK5, an ERK1/2-related MAPK, is activated during mitosis and phosphorylates BIM(EL) to promote cell survival. Here we show that treatment of cells with nocodazole or paclitaxel does cause phosphorylation of BIM(EL), which is independent of ERK1/2. However, this was not due to ERK5-catalysed phosphorylation, since it was not reversed by the MEK5 inhibitor BIX02189 and proceeded normally in ERK5-/- fibroblasts. Indeed, although ERK5 is phosphorylated at multiple sites in the C-terminal transactivation region during mitosis, these do not include the activation-loop and ERK5 kinase activity does not increase. Mitotic phosphorylation of BIM(EL) occurred at proline-directed phospho-acceptor sites and was abolished by selective inhibition of CDK1. Furthermore, cyclin B1 was able to interact with BIM and cyclin B1/CDK1 complexes could phosphorylate BIM in vitro. Finally, we show that CDK1-dependent phosphorylation of BIM(EL) drives its polyubiquitylation and proteasome-dependent degradation to protect cells during mitotic arrest. These results provide new insights into the regulation of BIM(EL) and may be relevant to the therapeutic use of agents such as paclitaxel.

Summary Phosphoinositide 3-kinases (PI3Ks) are essential for cell growth, migration, and survival. The structure of a p110β/p85β complex identifies an inhibitory function for the C-terminal SH2 domain (cSH2) of the p85 regulatory subunit. Mutagenesis of a cSH2 contact residue activates downstream signaling in cells. This inhibitory contact ties up the C-terminal region of the p110β catalytic subunit, which is essential for lipid kinase activity. In vitro, p110β basal activity is tightly restrained by contacts with three p85 domains: the cSH2, nSH2, and iSH2. RTK phosphopeptides relieve inhibition by nSH2 and cSH2 using completely different mechanisms. The binding site for the RTK's pYXXM motif is exposed on the cSH2, requiring an extended RTK motif to reach and disrupt the inhibitory contact with p110β. This contrasts with the nSH2 where the pY-binding site itself forms the inhibitory contact. This establishes an unusual mechanism by which p85 SH2 domains contribute to RTK signaling specificities., Graphical Abstract Highlights ► Both nSH2 and cSH2 domains of p85 inhibit basal activity of p110β ► p110β/p85β structure shows cSH2 contacts the C terminus of p110β ► Relief of cSH2 inhibition, unlike nSH2, requires extending beyond the pYXXM motif ► p110β C terminus is critical for phosphorylation of lipids and activation by RTKs

Summary Objectives The primary aim of this study was to investigate the immediate effect on restricted active ankle joint dorsiflexion range of motion (ROM), after a single intervention of trigger point (TrP) pressure release on latent soleus myofascial trigger points (MTrPs). The secondary aim was to assess aspects of the methodological design quality, identify limitations and propose areas for improvement in future research. Design A pilot randomised control trial. Participants Twenty healthy volunteers (5 men and 15 women; mean age 21.7±2.1 years) with a restricted active ankle joint dorsiflexion. Intervention Participants underwent a screening process to establish both a restriction in active ankle dorsiflexion and the presence of active and latent MTrPs in the soleus muscle. Participants were then randomly allocated to an intervention group (TrP pressure release) or control group (no therapy). Results The results showed a statistically significant ( p =0.03) increase of ankle ROM in the intervention compared to the control group. Conclusion This study identified an immediate significant improvement in ankle ROM after a single intervention of TrP pressure release on latent soleus MTrPS. These findings are clinically relevant, although the treatment effect on ankle ROM is smaller than a clinical significant ROM (5°). Suggestions for methodological improvements may inform future MTrP research and ultimately benefit clinical practice in this under investigated area.

Summary The PI3K signaling pathway regulates cell growth and movement and is heavily mutated in cancer. Class I PI3Ks synthesize the lipid messenger PI(3,4,5)P3. PI(3,4,5)P3 can be dephosphorylated by 3- or 5-phosphatases, the latter producing PI(3,4)P2. The PTEN tumor suppressor is thought to function primarily as a PI(3,4,5)P3 3-phosphatase, limiting activation of this pathway. Here we show that PTEN also functions as a PI(3,4)P2 3-phosphatase, both in vitro and in vivo. PTEN is a major PI(3,4)P2 phosphatase in Mcf10a cytosol, and loss of PTEN and INPP4B, a known PI(3,4)P2 4-phosphatase, leads to synergistic accumulation of PI(3,4)P2, which correlated with increased invadopodia in epidermal growth factor (EGF)-stimulated cells. PTEN deletion increased PI(3,4)P2 levels in a mouse model of prostate cancer, and it inversely correlated with PI(3,4)P2 levels across several EGF-stimulated prostate and breast cancer lines. These results point to a role for PI(3,4)P2 in the phenotype caused by loss-of-function mutations or deletions in PTEN., Graphical Abstract, Highlights • PTEN is a PI(3,4)P2 3-phosphatase • PTEN and INPP4B regulate PI(3,4)P2 accumulation downstream of class I PI3K • PTEN regulates PI(3,4)P2-dependent activation of Akt and formation of invadopodia • PI(3,4)P2 signaling may play a role in the tumor suppressor function of PTEN, Malek et al. show that the tumor suppressor PTEN acts as a PI(3,4)P2 3-phosphatase within the growth factor-stimulated PI3K signaling network, in addition to its accepted role as a PI(3,4,5)P3 3-phosphatase. This suggests that specific PI(3,4)P2 effector functions, such as invadopodia formation, play a role in the PTEN-loss-of-function phenotype.

Prototype irreversible inhibitors of the cysteinyl protease Der p I were designed, synthesised and evaluated in vitro. Candidates were designed using a modular approach, whereby a peptide sequence was appended with known thiophilic moieties. This hinged on utilizing peptide sequences from substrate specificity data compiled using proprietary RAPiD technology.

Aims To provide a differential diagnosis/histogenesis of squa-mous epithelial-lined cysts of the ovary (SECO). Methods A case of a 42-year-old with a history of ovarian cystec-tomy for strumal carcinoid, presenting with a squamous epithelial-lined cyst in an ipsilateral oophorectomy and confirmed as residual teratoma, was reviewed. A literature search was also conducted. Results Oophorectomy showed a keratin-filled cyst lined by mature stratified squamous epithelium with no skin adnexae or other overt tissue elements and resembling epidermoid cyst (EC). The entire lesion was processed and a single, small focus of smooth muscle identified in the cyst wall. Discussion EC is included in the WHO classification under monodermal teratomas, although its histogenesis is still controver-sial. 1 Some authors have shown that many EC reflect inadequately sampled teratomas or metaplasia in Brenner tumours and endome-triosis, and suggest pure EC probably comprise 2 Other possibilities include metaplasia in surface epithelial tumours, epithelial inclusion cysts, rete ovarii or hilar mesonephric tubules, while skin implantation during previous surgery has also been suggested. 1 As teratoma and EC may have different clinical follow-up, accurate diagnosis is important. 1 Our case highlights the importance of correlation with previous pathology and complete submission of the lesion to identify less prominent teratomatous components.