The impact of electronic pathways and digital systems on neck of femur fracture outcomes globally: a systematic review

INTRODUCTION

Electronic pathways (e-pathways) and digital systems are novel interventions with several uses in healthcare, ranging from clinical decision support systems to checklists for care delivery. Their application in the management of neck of femur (NOF) fractures is evolving and they may play a key role in facilitating improvements in care delivery. The primary aim of this review was to outline the impact of e-pathways/digital systems on NOF fracture outcomes.

METHODS

A systematic literature search was performed using the PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) guidelines. A total of 698 citations were evaluated, of which 38 passed the inclusion/exclusion criteria. Six studies were then finalised following full-text review. Heterogenous data meant a narrative synthesis was undertaken. Risk of bias for each paper was assessed using the Downs and Black scale.

RESULTS

A statistically significant improvement was demonstrated for time to theatre (3/6 studies), length of hospital stay (2/6 studies) and secondary fracture prevention (2/6 studies). Although postoperative delirium and mortality improved with the introduction of e-pathways/digital systems, statistical significance was not achieved. No outcome measures were adversely affected.

CONCLUSIONS

This systematic review of the literature demonstrates that e-pathways and digital systems are promising novel interventions, displaying a significant positive impact on several NOF fracture outcomes. Owing to the novel nature of e-pathways and digital systems in orthopaedics, a limited number of studies were identified for review, each with variable study design. More high quality homogenous prospective cohort studies with a standardised primary outcome measure are required for more definitive conclusions of efficacy to be drawn.

Optimization of biogas potential using kinetic models, response surface methodology, and instrumental evidence for biodegradation of tannery fleshings during anaerobic digestion

The optimization of the batch size experiment was run for a hydraulic retention time of 45 days using proteolytic enzyme pretreatment. The highest amounts of biogas were produced in comparison to conventional BDS (25:75), which is not processed with enzymes, and there was an increase in the biogas generation of 13.9 and 18.57%. The kinetic models show the goodness of fit between 0.993 and 0.998 and the correlation coefficient's value domain was [-1, 1] from a statistical perspective. The Box-Behnken design was carried out using the response surface methodology at different levels of independent parameters to optimize the process. Different instruments were evaluated to determine the chemical structure change and the contamination of the different treatments and the raw sample of tannery fleshings was determined. Thermogravimetric analysis was conducted to determine the loss of weight on thermal degradation. The Fourier transform infrared spectrometry was carried out to determine the different functional groups, such as -OH, -CH, -NH, and C-O, present in the samples of tannery fleshings. Scanning electron microscopy and energy dispersive X-ray analysis were carried out to determine the morphological alterations in the substrate, digestate, enzyme-pretreated fleshings, and the chemical composition of samples.

Synthesis of carbon molecular sieves from agricultural residues: Status, challenges and prospects

Adsorption is the most promising technology used in the gas separation and purification process. The key success of this technology relies on the selection of an adsorbent. Activated carbon and zeolites are the most commonly used adsorbents in the separation of particular gas from gaseous mixtures. Activated carbon deriving from fossil and biomass-based resources has wide pore size distribution and thereby results in lower selectivity. Whereas, zeolites synthesized from natural minerals are expensive which increases the cost of the purification process. Taking this into concern, the quest for synthesizing low-cost and effective adsorbents has gained greater attention in recent years. Carbon Molecular Sieves (CMSs), are considered as an attractive alternative to replace the conventional adsorbents. Furthermore, CMSs exhibit higher selectivity and adsorption capacity, due to their narrow micropore size distribution (0.3-0.5 nm). CMSs are synthesized from any organic carbonaceous precursor with low inorganic content. Since most of the agricultural residues fall under this category, they can be used as a feedstock for CMSs production. The synthesis of CMSs involves three stages: carbonization, activation, and pore modification. In this review, physicochemical characteristics of various agricultural residues, the effects of carbonization process parameters, activation methods, and pore modification techniques adopted for producing CMSs are comprehensively discussed. The effect of deposition temperature, time, and flow rate of depositing agent on pore characteristics of CMSs is briefed. The prospects and challenges in CMSs production are also studied. The insights in this review provide guidelines for synthesizing CMSs from agro-residues.

Forced symmetry breaking as a mechanism for rogue bursts in a dissipative nonlinear dynamical lattice

We propose an alternative to the standard mechanisms for the formation of rogue waves in a nonconservative, nonlinear lattice dynamical system. We consider an ordinary differential equation (ODE) system that features regular periodic bursting arising from forced symmetry breaking. We then connect such potentially exploding units via a diffusive lattice coupling and investigate the resulting spatiotemporal dynamics for different types of initial conditions (localized or extended). We find that in both cases, particular oscillators undergo extremely fast and large amplitude excursions, resembling a rogue wave burst. Furthermore, the probability distribution of different amplitudes exhibits bimodality, with peaks at both vanishing and very large amplitude. While this phenomenology arises over a range of coupling strengths, for large values thereof the system eventually synchronizes and the above phenomenology is suppressed. We use both distributed (such as a synchronization order parameter) and individual oscillator diagnostics to monitor the dynamics and identify potential precursors to large amplitude excursions. We also examine similar behavior with amplitude-dependent diffusive coupling.

Solving neurodegeneration: common mechanisms and strategies for new treatments

Across neurodegenerative diseases, common mechanisms may reveal novel therapeutic targets based on neuronal protection, repair, or regeneration, independent of etiology or site of disease pathology. To address these mechanisms and discuss emerging treatments, in April, 2021, Glaucoma Research Foundation, BrightFocus Foundation, and the Melza M. and Frank Theodore Barr Foundation collaborated to bring together key opinion leaders and experts in the field of neurodegenerative disease for a virtual meeting titled "Solving Neurodegeneration". This "think-tank" style meeting focused on uncovering common mechanistic roots of neurodegenerative disease and promising targets for new treatments, catalyzed by the goal of finding new treatments for glaucoma, the world's leading cause of irreversible blindness and the common interest of the three hosting foundations. Glaucoma, which causes vision loss through degeneration of the optic nerve, likely shares early cellular and molecular events with other neurodegenerative diseases of the central nervous system. Here we discuss major areas of mechanistic overlap between neurodegenerative diseases of the central nervous system: neuroinflammation, bioenergetics and metabolism, genetic contributions, and neurovascular interactions. We summarize important discussion points with emphasis on the research areas that are most innovative and promising in the treatment of neurodegeneration yet require further development. The research that is highlighted provides unique opportunities for collaboration that will lead to efforts in preventing neurodegeneration and ultimately vision loss.

Consensus Recommendation for Mouse Models of Ocular Hypertension to Study Aqueous Humor Outflow and Its Mechanisms

Due to their similarities in anatomy, physiology, and pharmacology to humans, mice are a valuable model system to study the generation and mechanisms modulating conventional outflow resistance and thus intraocular pressure. In addition, mouse models are critical for understanding the complex nature of conventional outflow homeostasis and dysfunction that results in ocular hypertension. In this review, we describe a set of minimum acceptable standards for developing, characterizing, and utilizing mouse models of open-angle ocular hypertension. We expect that this set of standard practices will increase scientific rigor when using mouse models and will better enable researchers to replicate and build upon previous findings.

Biogenesis of Zirconium Oxide Nanoparticles by Momordica charantia (Bitter Gourd) Leaf Extract: Characterization and their Antimicrobial Activities

Aims: To determine the antimicrobial activity of zirconium oxide nanoparticles (ZrO2 NPs) synthesized by Justicia Adhatoda leaf extract. Study Design: Synthesis, characterization and antibacterial activity determination of ZrO2 NPs. Place and Duration of Study: PG and Research Department of Chemistry, V.O.Chidambaram College, Tuticorin, Tamilnadu, India, between April 2020 and April 2021. Methodology: Justicia adhatoda leaf extract was used to synthesize ZrO2 NPs. UV-Visible spectroscopy was used to characterize ZrO2 NPs. Using Fourier transform infrared spectroscopy, the function of biomolecules in plant extract in the synthesis of ZrO2 NPs was identified. XRD was used to determine the particle size of nanparticles. ZrO2 NPs were evaluated for antimicrobial activity. Results: The synthesis of ZrO2 NPs was clearly visible in an absorbance band at 321 nm in the UV–visible spectrum. The absorption peak of ZrO2 NPs in the FTIR was 880 cm-1, confirming the Zr–O vibrational mode in ZrO2 NPs. As evidenced by XRD measurements, the average crystallite size of ZrO2 NPs was found to be 40 nm. The biosynthesized ZrO2 NPs were found to have potent antibacterial action against Escherichia coli bacteria and Staphylococcus aureus bacteria. Conclusion: ZrO2 NPs mediated by Justicia adhatoda leaf extract have demonstrated substantial antibacterial activity

Antibacterial Activity of CuO Nanoparticles Synthesized by Justicia adhatoda Leaf Extract

Aims: To determine the antibacterial activity of CuO nanoparticles (CuO NPs) synthesized by Justicia adhatoda leaf extract. Study Design:  Synthesis, characterization and antibacterial activity determination of CuO NPs. Place and Duration of Study: PG and Research Department of Chemistry, V.O.Chidambaram College, Tuticorin, Tamilnadu, India, between April 2019 and April 2020. Methodology: CuO NPs were synthesised using Justicia adhatoda leaf extract. UV-Visible spectroscopy was used to characterize CuO NPs. The role of biomolecules in plant extract in the formation of the CuO NPs was identified using Fourier transform infrared spectroscopy. The particle size and lattice properties of CuO NPs were determined using XRD. The surface morphology of CuO NPs was studied using SEM. The presence of Cu and O in CuO NPs was confirmed using EDAX analysis. Bacterial antimicrobial activity was investigated. Results: An absorbance band at 285 nm in the UV–visible spectrum clearly revealed the formation of CuO NPs. In the FTIR, CuO NPs had a distinct absorption peak at 608 cm-1, confirming metal–oxygen stretching in Cu-O nanostructures. The presence of crystalline CuO NPs was confirmed by XRD patterns, and they were found to be spherical in shape with a size range of 23.21–37.57 nm, as evidenced by FESEM. The biosynthesized CuO NPs exhibited a strong antibacterial activity against Staphylococcus epidermidis and Bacillus cereus bacteria. Conclusion: Justicia adhatoda leaf extract mediated CuO NPs have shown significant antibacterial activity and they are considered potent antibacterial agents.

Kinetic and thermodynamic study of finger millet straw pyrolysis through thermogravimetric analysis

Pyrolysis kinetics of finger millet straw (FMS) was studied using a thermogravimetric analyzer under N₂ environment. Physico-chemical characteristics of FMS were comparable with the established pyrolysis feedstocks. FMS thermally decomposed in three stages: drying, active pyrolysis, and char formation resulting in 70.37% overall weight loss. Average activation energy determined by Friedman and Starink methods was 177.80 and 172.18 kJ mol^-1, respectively. Frequency factor was found to be in the range of 10⁸ to 10²⁹. Reaction pathway followed diffusion, nucleation, and order-based mechanisms. The pyrolysis of FMS was characterized by empirical modeling and predicted well with model adequacy of 97.55%. Thermodynamic parameters (ΔG and ΔH) revealed the non-spontaneous and endothermic nature of FMS pyrolysis. The biochar obtained at multiple heating rates were characterized for its physicochemical, functional, and morphological characteristics. The kinetic and thermodynamic analyses illustrate the feasibility of exploiting finger millet straw as a pyrolysis feedstock to derive biofuels.

Density Distribution in Soft Matter Crystals and Quasicrystals

The density distribution in solids is often represented as a sum of Gaussian peaks (or similar functions) centered on lattice sites or via a Fourier sum. Here, we argue that representing instead the logarithm of the density distribution via a Fourier sum is better. We show that truncating such a representation after only a few terms can be highly accurate for soft matter crystals. For quasicrystals, this sum does not truncate so easily, nonetheless, representing the density profile in this way is still of great use, enabling us to calculate the phase diagram for a three-dimensional quasicrystal-forming system using an accurate nonlocal density functional theory.

Resuming elective hip and knee arthroplasty in the COVID-19 era: a unique insight into patient risk aversion and sentiment

INTRODUCTION

There has been guidance from the government and orthopaedic community on how best to ensure the safety of our patients and colleagues as we recommence elective surgery in the UK. The primary aim was to determine what proportion of patients feel they should proceed with their elective hip and knee arthroplasty surgery during the COVID-19 climate. The secondary aim was to investigate what variables affected this decision.

METHODS

Patient information from a single surgeon's waiting list in a district general hospital were recorded. A standardised telephone discussion was had with all the patients noting the severity of pain and the potential reasons for not wanting to proceed with surgery.

RESULTS

A total of 70.6% (96/136) of patients wished to proceed with surgery; 29.4% (40/136) did not wish to proceed. The decision to proceed with surgery was not correlated with sex, American Society of Anesthesiologists grade or COVID-19 risk. Those who wished to proceed with surgery had a mean age of 68.5 years while those who did not had a mean age of 72.4 years (P = 0.03). Within the matched subgroups, patients under the age of 70 years were more willing to proceed with primary hip arthroplasty surgery (87.9%) compared with primary knee arthroplasty surgery (57.1%; P = 0.007); 75% of the patients who did not wish to proceed with surgery expressed concerns about perioperative COVID-19 infection.

CONCLUSION

There is a significant proportion of arthroplasty patients on waiting lists who would be willing to accept the increased risks associated with COVID-19 to undergo surgery on an urgent basis. The subgroup of younger patients awaiting hip arthroplasty is more willing than those awaiting knee arthroplasty to proceed with surgery.

Which Wave Numbers Determine the Thermodynamic Stability of Soft Matter Quasicrystals?

For soft matter to form quasicrystals an important ingredient is to have two characteristic length scales in the interparticle interactions. To be more precise, for stable quasicrystals, periodic modulations of the local density distribution with two particular wave numbers should be favored, and the ratio of these wave numbers should be close to certain special values. So, for simple models, the answer to the title question is that only these two ingredients are needed. However, for more realistic models, where in principle all wave numbers can be involved, other wave numbers are also important, specifically those of the second and higher reciprocal lattice vectors. We identify features in the particle pair interaction potentials that can suppress or encourage density modes with wave numbers associated with one of the regular crystalline orderings that compete with quasicrystals, enabling either the enhancement or suppression of quasicrystals in a generic class of systems.

Role of the PNPLA2 Gene in the Regulation of Oxidative Stress Damage of RPE

Oxidative stress-mediated injury of the retinal pigment epithelium (RPE) can precede progressive retinal degeneration and ultimately lead to blindness (e.g., age-related macular degeneration (AMD)). The RPE expresses the PNPLA2 gene and produces its protein product PEDF-R that exhibits lipase activity. We have shown that transient PNPLA2 overexpression decreases dead-cell proteolytic activity and that synthetic peptides derived from a central region of PEDF-R efficiently protect ARPE-19 and pig primary RPE cells from oxidative stress. This study aims to evaluate the effect of loss of PNPLA2 in RPE cells undergoing oxidative stress. Loss of PNPLA2 conferred increased resistance to cells when subjected to oxidative stress.

Structural crossover in a model fluid exhibiting two length scales: Repercussions for quasicrystal formation

We investigate the liquid state structure of the two-dimensional model introduced by Barkan et al. [Phys. Rev. Lett. 113, 098304 (2014)10.1103/PhysRevLett.113.098304], which exhibits quasicrystalline and other unusual solid phases, focusing on the radial distribution function g(r) and its asymptotic decay r→∞. For this particular model system, we find that as the density is increased there is a structural crossover from damped oscillatory asymptotic decay with one wavelength to damped oscillatory asymptotic decay with another distinct wavelength. The ratio of these wavelengths is ≈1.932. Following the locus in the phase diagram of this structural crossover leads directly to the region where quasicrystals are found. We argue that identifying and following such a crossover line in the phase diagram towards higher densities where the solid phase(s) occur is a good strategy for finding quasicrystals in a wide variety of systems. We also show how the pole analysis of the asymptotic decay of equilibrium fluid correlations is intimately connected with the nonequilibrium growth or decay of small-amplitude density fluctuations in a bulk fluid.

Pigment epithelium-derived factor hinders photoreceptor cell death by reducing intracellular calcium in the degenerating retina

Calcium ions play a critical role in neuronal cell death. Pigment epithelium-derived factor (PEDF) is a promising neuroprotective protein for photoreceptor cells but the mechanisms mediating its effects against retinal degeneration are still not well characterized. We addressed this question in the rd1 degenerating mouse retina that bears a mutation in the Pde6b gene encoding one subunit of the phosphodiesterase enzyme. Loss of phosphodiesterase activity in rod photoreceptor cells increases cyclic guanosine monophosphate (cGMP) levels leading to a rise in intracellular calcium. Short-term treatments with recombinant human PEDF protein decreased intracellular calcium in photoreceptors in vivo. Taking advantage of calcium pump blockers, we defined that PEDF signaling acts on PMCA calcium pumps to lower intracellular calcium. PEDF restrained cell death pathways activated by high calcium levels and engaging calpains, BAX and AIF. The neurotrophic effects were mediated by the PEDF receptor (PEDF-R), encoded by the PNPLA2 gene. Finally, peptides containing the neurotrophic domain of PEDF targeted these same cell death pathways in vivo. The findings reveal rescue from death of degenerating photoreceptor cells by a PEDF-mediated preservation of intracellular calcium homeostasis.

Factors associated with nurses' perceptions about quality of end-of-life care

AIM

To examine the factors associated with nurses' perceptions of the quality of end-of-life care.

BACKGROUND

With increasing demand for hospitals to provide end-of-life care, the low quality of palliative care provided in hospital settings is an issue of growing concern in developing countries. Most dying patients receive their care from general nurses, irrespective of the nurses' specialty or level of training.

METHOD

A structured cross-sectional questionnaire survey was conducted of 553 nurses working at a teaching hospital in Malaysia.

RESULTS

The mean scores for nurses' knowledge about end-of-life care, their attitudes towards end-of-life care and the perceived quality of end-of-life care were low. The factors identified as significantly associated with the quality of end-of-life care were nurses' levels of knowledge and their attitudes towards end-of-life care.

DISCUSSION

Factors that contributed to the low quality of end-of-life care were inadequate knowledge and negative attitudes. These findings may reflect that end-of-life care education is not well integrated into nursing education.

CONCLUSION

The findings of this study suggest that there is a need to increase the nurses' level of knowledge and improve their attitude towards end-of-life care in order to enhance the quality of care provided to dying patients.

IMPLICATIONS FOR NURSING AND HEALTH POLICY

Nurse managers and hospital policymakers should develop strategies to enhance nurses' level of knowledge, as well as providing adequate emotional support for nurses who care for dying patients and their families. Nurses should be proactive in increasing their knowledge and adopting more positive attitudes towards end-of-life care.

Combining Medical Informatics and Bioinformatics toward Tools for Personalized Medicine

Objectives: Key bioinformatics and medical informatics research areas need to be identified to advance knowledge and understanding of disease risk factors and molecular disease pathology in the 21st century toward new diagnoses, prognoses, and treatments. Methods: Three high-impact informatics areas are identified: predictive medicine (to identify significant correlations within clinical data using statistical and artificial intelligence methods), along with pathway informatics and cellular simulations (that combine biological knowledge with advanced informatics to elucidate molecular disease pathology).

Results: Initial predictive models have been developed for a pilot study in Huntington’s disease. An initial bioinformatics platform has been developed for the reconstruction and analysis of pathways, and work has begun on pathway simulation.

Conclusions: A bioinformatics research program has been established at GE Global Research Center as an important technology toward next generation medical diagnostics. We anticipate that 21st century medical research will be a combination of informatics tools with traditional biology wet lab research, and that this will translate to increased use of informatics techniques in the clinic.

Imaging spectroscopy of solar radio burst fine structures

Solar radio observations provide a unique diagnostic of the outer solar atmosphere. However, the inhomogeneous turbulent corona strongly affects the propagation of the emitted radio waves, so decoupling the intrinsic properties of the emitting source from the effects of radio wave propagation has long been a major challenge in solar physics. Here we report quantitative spatial and frequency characterization of solar radio burst fine structures observed with the Low Frequency Array, an instrument with high-time resolution that also permits imaging at scales much shorter than those corresponding to radio wave propagation in the corona. The observations demonstrate that radio wave propagation effects, and not the properties of the intrinsic emission source, dominate the observed spatial characteristics of radio burst images. These results permit more accurate estimates of source brightness temperatures, and open opportunities for quantitative study of the mechanisms that create the turbulent coronal medium through which the emitted radiation propagates.

Radio observations of the solar atmosphere provide a unique view on the non-thermal processes in the outer atmosphere. Here the authors use LOFAR observations to demonstrate that the observed radio burst characteristics are dominated by propagation effects rather than underlying emission variations.

Comparison of two neurotrophic serpins reveals a small fragment with cell survival activity

PURPOSE

Protease nexin-1 (PN-1), a serpin encoded by the SERPINE2 gene, has serine protease inhibitory activity and neurotrophic properties in the brain. PN-1 inhibits retinal angiogenesis; however, PN-1's neurotrophic capacities in the retina have not yet been evaluated. Pigment epithelium-derived factor (PEDF) is a serpin that exhibits neurotrophic and antiangiogenic activities but lacks protease inhibitory properties. The aim of this study is to compare PN-1 and PEDF.

METHODS

Sequence comparisons were performed using computer bioinformatics programs. Mouse and bovine eyes, human retina tissue, and ARPE-19 cells were used to prepare RNA and protein samples. Interphotoreceptor matrix lavage was obtained from bovine eyes. Gene expression and protein levels were evaluated with reverse-transcription PCR (RT-PCR) and western blotting, respectively. Recombinant human PN-1, a version of PN-1 referred to as PN-1[R346A] lacking serine protease inhibitory activity, and PEDF proteins were used, as well as synthetic peptides designed from PEDF and PN-1 sequences. Survival activity in serum-starved, rat-derived retinal precursor (R28) cells was assessed with terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labeling (TUNEL) cell death assays. Bcl2 levels were measured with RT-PCR.

RESULTS

PN-1 is analogous in primary and tertiary structure to PEDF. A region in PN-1 shares homology with the neurotrophic active region of PEDF, a 17-residue region within alpha helix C. The native human retina, ARPE-19 cells, and murine RPE and retina expressed the gene for PN-1 (SERPINE2 and Serpine2 mRNA). The retina, ARPE-19 cell lysates, and bovine interphotoreceptor matrix contained PN-1 protein. The addition of PN-1, PN-1[R346A], or the 17mer peptide of PN-1 to serum-starved retina cells decreased the number of TUNEL-positive nuclei relative to the untreated cells, such as PEDF. PN-1, PN-1[R346A], and PN-1-17mer treatments increased the Bcl2 transcript levels in serum-starved cells, as seen with PEDF.

CONCLUSIONS

PN-1 and PEDF share structural and functional features, and expression patterns in the retina. These serpins' mechanisms of action as cell survival factors are independent of serine protease inhibition. We have identified PN-1 as a novel factor for the retina that may play a neuroprotective role in vivo, and small peptides as relevant candidates for preventing retinal degeneration.

A Novel Inhibitor of 5-Lipoxygenase (5-LOX) Prevents Oxidative Stress-Induced Cell Death of Retinal Pigment Epithelium (RPE) Cells

PURPOSE

5-Lipoxygenase (5-LOX) oxygenates arachidonic acid to form 5-hydroperoxyeicosatetraenoic acid, which is further converted into biologically detrimental leukotrienes, such as leukotriene B4 (LTB4). The RPE and retina express the PNPLA2 gene for pigment epithelium-derived factor receptor (PEDF-R), a lipase involved in cell survival. The purpose here was to investigate the role of PEDF-R on the 5-LOX pathway in oxidative stress of RPE.

METHODS

Lipoxygenase activity assays were performed with soybean and potato lipoxygenase. Binding was evaluated by peptide-affinity chromatography and pull-down assays with PEDF-R-derived synthetic peptides or recombinant protein. Oxidative stress was induced in human ARPE-19 and primary pig RPE cells with indicated concentrations of H2O2/TNF-α. Reverse transcription-PCR of ALOX5 and PNPLA2 genes was performed. Cell viability and death rates were determined using respective biomarkers. Leukotriene B4 levels were measured by ELISA.

RESULTS

Among five peptides spanning between positions Leu159 and Met325 of human PEDF-R polypeptide, only two overlapping peptides, E5b and P1, bound and inhibited lipoxygenase activity. Human recombinant 5-LOX bound specifically to peptide P1 and to His6/Xpress-tagged PEDF-R via ionic interactions. The two inhibitor peptides E5b and P1 promoted cell viability and decreased cell death of RPE cells undergoing oxidative stress. Oxidative stress decreased the levels of PNPLA2 transcripts with no effect on ALOX5 expression. Exogenous additions of P1 peptide or overexpression of the PNPLA2 gene decreased both LTB4 levels and death of RPE cells undergoing oxidative stress.

CONCLUSIONS

A novel peptide region of PEDF-R inhibits 5-LOX, which intersects with RPE cell death pathways induced by oxidative stress.

SYN-004 (ribaxamase), an oral beta-lactamase, mitigates antibiotic-mediated dysbiosis in a porcine gut microbiome model

AIM

To evaluate an antibiotic inactivation strategy to protect the gut microbiome from antibiotic-mediated damage.

METHODS AND RESULTS

SYN-004 (ribaxamase) is an orally delivered beta-lactamase intended to degrade penicillins and cephalosporins within the gastrointestinal tract to protect the microbiome. Pigs (20 kg, n = 10) were treated with ceftriaxone (CRO) (IV, 50 mg kg^-1 , SID) for 7 days and a cohort (n = 5) received ribaxamase (PO, 75 mg, QID) for 9 days beginning the day before antibiotic administration. Ceftriaxone serum levels were not statistically different in the antibiotic-alone and antibiotic + ribaxamase groups, indicating ribaxamase did not alter systemic antibiotic levels. Whole-genome metagenomic analyses of pig faecal DNA revealed that CRO caused significant changes to the gut microbiome and an increased frequency of antibiotic resistance genes. With ribaxamase, the gut microbiomes were not significantly different from pretreatment and antibiotic resistance gene frequency was not increased.

CONCLUSION

Ribaxamase mitigated CRO-mediated gut microbiome dysbiosis and attenuated propagation of the antibiotic resistance genes in pigs.

SIGNIFICANCE AND IMPACT OF THE STUDY

Damage of the microbiome can lead to overgrowth of pathogenic organisms and antibiotic exposure can promote selection for antibiotic-resistant micro-organisms. Ribaxamase has the potential to become the first therapy designed to protect the gut microbiome from antibiotic-mediated dysbiosis and reduce emergence of antibiotic resistance.

Minimally invasive periacetabular osteotomy using a modified Smith-Petersen approach: technique and early outcomes

AIMS

Periacetabular osteotomy is an effective way of treating symptomatic hip dysplasia. We describe a new minimally invasive technique using a modification of the Smith-Peterson approach. We performed a prospective, longitudinal cohort study to assess for any compromise in acetabular correction when using this approach, and to see if the procedure would have a higher complication rate than that quoted in the literature for other approaches. We also assessed for any improvement in functional outcome.

PATIENTS AND METHODS

From 168 consecutive patients (189 hips) who underwent acetabular correction between March 2010 and March 2013 we excluded those who had undergone previous pelvic surgery for DDH and those being treated for acetabular retroversion. The remaining 151 patients (15 men, 136 women) (166 hips) had a mean age of 32 years (15 to 56) and the mean duration of follow-up was 2.8 years (1.2 to 4.5). In all 90% of cases were Tönnis grade 0 or 1. Functional outcomes were assessed using the Non Arthritic Hip Score (NAHS), University of California, Los Angeles (UCLA) and Tegner activity scores.

RESULTS

The mean pre-operative lateral centre-edge angle was 14.2° (-5° to 30°) and the mean acetabular index was 18.4° (4° to 40°). Post-operatively these were 31° (18° to 46°) and 3° (-7° to 29°), respectively, a significant improvement in both (p < 0.001). Allogenic blood transfusion was required in two patients (1.2%). There were no major nerve or vascular complications, and no wound infections. At the time of last follow-up, we noted a significant improvement in functional outcome scores: UCLA improved by 2.31 points, Tegner improved by 1.08 points, and the NAHS improved by 25.4 points (p < 0.001 for each). Hypermobility and longer duration of surgery were significant negative predictors for a good post-operative UCLA score, while residual retroversion was a positive predictor of post-operative UCLA score.

CONCLUSION

We have found this approach to be safe and effective, facilitating early recovery from surgery. Cite this article: Bone Joint J 2017;99-B:22-8.

Perceptions of Healthcare Professionals on the Usage of Percutaneous Endoscopic Gastrostomy in a Teaching Hospital from a Middle-Income South East Asian Country

OBJECTIVE

To explore the perceptions of healthcare professionals' (HCPs) in a South East Asian nation towards percutaneous endoscopic gastrostomy (PEG) feeding.

DESIGN

Semi-structured, qualitative interviews.

SETTINGS

A teaching hospital in Kuala Lumpur, Malaysia.

PARTICIPANTS

A total of 17 healthcare professionals aged 23-43 years, 82% women.

RESULTS

Thematic analysis revealed five themes that represent HCPs' perceptions in relation to the usage of PEG feeding: 1) knowledge of HCPs, 2) communication, 3) understanding among patients, and 4) financial and affordability.

CONCLUSION

The rationale for reluctance towards PEG feeding observed in this regions was explained by lack of education, knowledge, communication, team work, and financial support. Future studies should assess the effects of educational programmes among HCPs and changes in policies to promote affordability on the utilization of PEG feeding in this region.

Transient Weakening of Earth's Magnetic Shield Probed by a Cosmic Ray Burst

The GRAPES-3 tracking muon telescope in Ooty, India measures muon intensity at high cutoff rigidities (15-24 GV) along nine independent directions covering 2.3 sr. The arrival of a coronal mass ejection on 22 June 2015 18:40 UT had triggered a severe G4-class geomagnetic storm (storm). Starting 19:00 UT, the GRAPES-3 muon telescope recorded a 2 h high-energy (∼20  GeV) burst of galactic cosmic rays (GCRs) that was strongly correlated with a 40 nT surge in the interplanetary magnetic field (IMF). Simulations have shown that a large (17×) compression of the IMF to 680 nT, followed by reconnection with the geomagnetic field (GMF) leading to lower cutoff rigidities could generate this burst. Here, 680 nT represents a short-term change in GMF around Earth, averaged over 7 times its volume. The GCRs, due to lowering of cutoff rigidities, were deflected from Earth's day side by ∼210° in longitude, offering a natural explanation of its night-time detection by the GRAPES-3. The simultaneous occurrence of the burst in all nine directions suggests its origin close to Earth. It also indicates a transient weakening of Earth's magnetic shield, and may hold clues for a better understanding of future superstorms that could cripple modern technological infrastructure on Earth, and endanger the lives of the astronauts in space.

Ventilator Associated Pneumonia in an Infant Caused by Stenotrophomonas maltophila - A Case Report

Stenotrophomonas maltophila (S.maltophila) is an aerobic Gram-negative bacillus that is a frequent colonizer of fluids used in the hospital setting. The organism is known to cause life threatening infections in immuno-compromised patients especially in those who are neutropenic, on chemotherapy or on broad spectrum antibiotics. We report a case of ventilator associated pneumonia caused by Stenotrophomonas maltophila in a two-month old infant who later developed multi organ dysfunction syndrome. In seriously ill paediatric patients, S.maltophila should also be considered as a possible pathogen for Ventilator-Associated Pneumonia (VAP), hence empiric antibiotic choice should include antimicrobials that are active against S. maltophila. An early identification and treatment of VAP with Multi-Drug Resistant (MDR) strains with appropriate antibiotics has a significant impact on morbidity and mortality.

Three-Dimensional Icosahedral Phase Field Quasicrystal

We investigate the formation and stability of icosahedral quasicrystalline structures using a dynamic phase field crystal model. Nonlinear interactions between density waves at two length scales stabilize three-dimensional quasicrystals. We determine the phase diagram and parameter values required for the quasicrystal to be the global minimum free energy state. We demonstrate that traits that promote the formation of two-dimensional quasicrystals are extant in three dimensions, and highlight the characteristics required for three-dimensional soft matter quasicrystal formation.

Small Retinoprotective Peptides Reveal a Receptor-binding Region on Pigment Epithelium-derived Factor

The cytoprotective effects of pigment epithelium-derived factor (PEDF) require interactions between an as of a yet undefined region with a distinct ectodomain on the PEDF receptor (PEDF-R). Here we characterized the area in PEDF that interacts with PEDF-R to promote photoreceptor survival. Molecular docking studies suggested that the ligand binding site of PEDF-R interacts with the neurotrophic region of PEDF (44-mer, positions 78-121). Binding assays demonstrated that PEDF-R bound the 44-mer peptide. Moreover, peptide P1 from the PEDF-R ectodomain had affinity for the 44-mer and a shorter fragment within it, 17-mer (positions 98-114). Single residue substitutions to alanine along the 17-mer sequence were designed and tested for binding and biological activity. Altered 17-mer[R99A] did not bind to the P1 peptide, whereas 17-mer[H105A] had higher affinity than the unmodified 17-mer. Peptides 17-mer, 17-mer[H105A], and 44-mer exhibited cytoprotective effects in cultured retina R28 cells. Intravitreal injections of these peptides and PEDF in the rd1 mouse model of retinal degeneration decreased the numbers of dying photoreceptors, 17-mer[H105A] being most effective. The blocking peptide P1 hindered their protective effects both in retina cells and in vivo. Thus, in addition to demonstrating that the region composed of positions 98-114 of PEDF contains critical residues for PEDF-R interaction that mediates survival effects, the findings reveal distinct small PEDF fragments with neurotrophic effects on photoreceptors.