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Stüve-Wiedemann syndrome (SWS) is a rare, autosomal recessive disorder, causing dysautonomia and multisystem failure. Symptoms include skeletal malformations, restricted joint mobility and desensitisation to pain. Patients with SWS presenting with intraoral lesions are extremely rare and this is probably due to their shortened lifespan. We present a case of a 9-month-old patient who presented to our Oral and Maxillofacial Surgery (OMFS)Unit with a chronic inflamed ulcer affecting the tongue, secondary to trauma from erupting central incisors. We believe that depapillation in conjunction with an increased pain threshold contributed to its development. The patient was successfully treated by extraction of the lower central incisors and intralesional steroid injections under general anaesthetic. This case highlights that patients with SWS can present to the OMFS clinician with oral lesions and that they can be safely managed under general anaesthesia.

Pediatric trauma has been affected by COVID-19, school closures, and stay at home advice. Health seeking behavior has decreased. The aim of this study is to assess trends in the presentation of maxillofacial soft tissue injuries and subsequent management within a regional pediatric hospital. Retrospective study over a 3-year period (from 2019 to 2021 between the months of January and April). Inclusion of all pediatric patients seen by Oral and Maxillofacial Surgery team. Between 2019 and 2021, the total number of patients dropped by over half. The average age dropped from 5.9 in 2019 to 3.8 in 2021. Males were more commonly seen. Falls are the most common cause of injuries across 2019 to 2021. Extraoral injuries increased by 21%. Intraoral injuries reduced by 8%. Lip lacerations accounted for most injuries. In 2020, there was 21% reduction in conservative management of injuries. Wound closure under local anesthetic peaked in 2020, by 12%. Wound closure under general anesthetic has increased by 5%, and accounts for nearly a third of all injuries in 2020 and 2021. Patients are becoming younger and more likely to be male. Conservative management is most common but closure under local anesthetic and general anesthetic has increased. This may indicate an increase in the severity of soft tissue injuries or a trend toward operative management. We also introduce a laceration grading scale for clinician use to assist in assessing and documenting injury severity. Further research is needed to assess whether these trends continue or revert to prepandemic trends.

Introduction The mandible is the most common bone to develop complications following treatment of facial fractures. This is due to a complex interaction of both fracture specific and patient factors. Our aim was to identify those patient factors, with a specific focus on those that may be potentially modifiable to reduce the incidence of complications. Method A systematic review of the literature was undertaken using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses methodology to identify patient factors ascribed to an increased risk of complications following mandible fracture treatment. These were divided non- modifiable and potentially modifiable factors. A meta-analysis was performed to weight those factors for which statistical analysis had been performed. Results 22 pertinent papers were identified, of which 8 described non-modifiable and 7 potentially modifiable factors. The most common potentially modifiable factor identified was smoking. Meta-analysis established that tobacco smoking demonstrated an increased risk of complications in three studies (OR: 4.04 – 8.09). Conclusions Division of patient factors into those that are potentially modifiable and those that are not will enable clinicians to focus on those in which change within the immediate post-operative period can be instigated. This includes smoking cessation assistance, education as to the need for a soft diet and facilitating post- operative clinic attendance. It also enables stratification of risk in terms of consent, and choice of treatment. Further research should use standardised terminology, particularly in stopping the use of generalizable terms such as patient compliance and instead describing its individual components.

Thermochemical heat storage is one of the most attractive technologies to store heat from solar thermal energy or waste heat from industrial processes for its high energy density and long-term storage capability. This research presents a novel expanded graphite/alginate polymer matrix encapsulated with hydrated salts as highly efficient thermochemical heat storage materials. Through the simple synthesis method, the composite material can be sized and shaped to fit multiple applications, and be easily scaled where needed. Through the reversible hydration and dehydration reaction, the incorporated CaCl2 salt can store and release heat. Thermal energy from solar thermal generators or low grade waste heat sources (2. A salt loading value of 84% has been achieved with visible porosity maintained. Static heat is used to study the charge reaction, whereas a flow of humid air through a packed bed is used to study the discharge reaction where temperature uplifts between 10–14 °C were observed. A vermiculite/CaCl2 composite is used as a comparison in both reactions. Additionally, bulk density, surface porosity, surface area, moisture sorption and thermal conductivity are considered. The results show that the novel composite materials developed in this study can achieve better packing density and comparable energy density comparing to the conventional vermiculite/CaCl2 composite, but with higher thermal conductivity leading to enhanced energy efficiency. Graphical Abstract

Proximal femur fractures in geriatric patients are associated with substantial mortality. Management of intracapsular proximal femur fractures has been based on age, displacement, cognition, and pre-injury mobility. However, over the last decade, there has been a tendency to offer arthroplasty rather than internal fixation for these patients irrespective of displacement, to allow early mobilisation and negate the higher rate of reoperation due to failed internal fixation. There are no previous investigations analysing whether the severity of fracture displacement is related to different patient characteristics.This study examines whether patients sustaining undisplaced or displaced intracapsular proximal femur fractures represent different patient groups with different pre-injury characteristics and post-operative mortality, irrespective of treatment modality.A retrospective series of 329 consecutive patients over the age of 55 years who sustained intracapsular proximal femur fractures, who underwent surgical management at a district general hospital over a period of 2 years (2012-2013) were identified using the national hip fracture database. Demographics, American Society of Anaesthesiologist (ASA) grade, pre-injury outdoor mobility status, cognitive status, and admission serum investigations, fracture displacement, type of surgery, and mortality rates at short term (2 years)long-term (7-9 years) were reviewed.There were 109 male and 220 female patients with a minimum follow-up of 7 years. The mean age at surgery was 81.6 years (range 55-103 years). There were 63 (19.1%) undisplaced fractures (Garden 12) and, 265 (80.5%) displaced fractures (Garden 34). The median survival in this cohort was 2.95 years (95% CI 2.3-3.6). Mortality rates were 77.4% (n=257) at long-term (7-9 years) follow-up. Admission patient characteristics showed no statistically significant difference between displaced and undisplaced fracture groups. This included ASA, pre-operative cognition, and mobility status. Fracture displacement was not an independent predictor of mortality at short or long term.In patients sustaining intracapsular proximal femur fractures, the degree of displacement is not a caveat for a different patient group. Fracture displacement is not predicted by the pre-injury level of function and does not predict short or long-term mortality.

Osteosclerotic metaphyseal dysplasia (OMD) is an extremely rare form of osteopetrosis, which bears significant clinical similarities to dysosteosclerosis (DSS). We aim to present a rare case of OMD with mandibular swelling and osteomyelitis infection including diagnosis journey as well as management in 7-year-old patient. Literature review completed for OMD cases. Case report investigative methods include genetic testing, CT facial bones and MRI scan, orthopantogram and bone biopsies. An initial suspected diagnosis of DSS with chronic osteomyelitis was made. However, following genetic testing, a diagnosis of OMD was confirmed. Our patient underwent a surgical debulking procedure and antibiotic treatment. Less than 10 patients with this condition have been reported within the international literature. There is a wide range of presentation. OMD, DSS and osteomyelitis are all within a similar spectrum of bone conditions. Our understanding, regarding OMD, remains limited and, hence, further research is required to elucidate a thorough clinical picture.

BACKGROUND: Diabetic ketoacidosis (DKA) is a medical emergency with a high mortality rate and is associated with severe metabolic acidosis and dehydration. DKA patients have an increased risk of arterial and venous thromboembolism, however little is known about this metabolic derangement in the first 24 hours of admission and to assess its effect on coagulation. We therefore utilised a novel functional marker of clot microstructure (fractal dimension - df) to assess these changes within the first 24 hours. METHODS: Prospective single centre observational study to demonstrate whether the tendency of blood clot formation differs in DKA patients. RESULTS: 15 DKA patients and 15 healthy matched controls were recruited. Mean df in the healthy control group was 1.74±0.03. An elevated df of 1.78±0.07 was observed in patients with DKA on admission. The mean pH on admission was 7.14±0.13 and the lactate was 3.6±2.0. df changed significantly in response to standard treatment and was significantly reduced to 1.68±0.09 (2–6& h) and to 1.66±0.08 at 24& h (p

INTRODUCTION Thrombosis is a severe and frequent complication of heparin-induced thrombocytopenia (HIT). However, there is currently no knowledge of the effects of HIT-like antibodies on the resulting microstructure of the formed clot, despite such information being linked to thrombotic events. We evaluate the effect of the addition of pathogenic HIT-like antibodies to blood on the resulting microstructure of the formed clot. MATERIALS AND METHODS Pathogenic HIT-like antibodies (KKO) and control antibodies (RTO) were added to samples of whole blood containing Unfractionated Heparin and Platelet Factor 4. The formed clot microstructure was investigated by rheological measurements (fractal dimension; df) and scanning electron microscopy (SEM), and platelet activation was measured by flow cytometry. RESULTS AND CONCLUSIONS Our results revealed striking effects of KKO on clot microstructure. A significant difference in df was found between samples containing KKO (df = 1.80) versus RTO (df = 1.74; p

Membranes with fast and selective ion transport are widely used for water purification and devices for energy conversion and storage including fuel cells, redox flow batteries and electrochemical reactors. However, it remains challenging to design cost-effective, easily processed ion-conductive membranes with well-defined pore architectures. Here, we report a new approach to designing membranes with narrow molecular-sized channels and hydrophilic functionality that enable fast transport of salt ions and high size-exclusion selectivity towards small organic molecules. These membranes, based on polymers of intrinsic microporosity containing Troger’s base or amidoxime groups, demonstrate that exquisite control over subnanometre pore structure, the introduction of hydrophilic functional groups and thickness control all play important roles in achieving fast ion transport combined with high molecular selectivity. These membranes enable aqueous organic flow batteries with high energy efficiency and high capacity retention, suggesting their utility for a variety of energy-related devices and water purification processes. Ion-selective membranes are widely used for water purification and electrochemical energy devices but designing their pore architectures is challenging. Membranes with narrow channels and hydrophilic functionality are shown to exhibit salt ions transport and selectivity towards small organic molecules.

The effects of varying percentage loadings of morpholine pre-treated cellulose nanofibrils (MCNF) and carboxymethylated cellulose nanofibrils (CMCNF) on the aqueous swelling, compressive modulus and viscoelastic properties of calcium-ion-crosslinked alginate hydrogels were investigated. In addition, the pore structures of hydrogels with the highest compressive modulus were studied. The incorporation of 5 wt. % MCNF resulted in a slightly reduced aqueous swelling, a 36% increase in compressive modulus and a layered pore structure when compared with the neat alginate hydrogel. On the other hand, the addition of CMCNF at the same loading led to a slightly improved aqueous swelling, an increase in compressive modulus (17%) and high porosity. Further increases in CNF loadings did not result in significant increase in material properties. The alginate/CNF composite materials have potentials to be used in applications where good swelling and mechanical robustness are required.

Measures of patient-reported quality of life (QoL) are increasingly being used to tailor services that are funded by Clinical Commissioning Groups (CCG) in England. Mandibular osteotomies may result in altered sensation of the lower lip, but we know of limited evidence about the resulting effect on QoL. The modified Bristol orthognathic patient outcomes questionnaire was given to patients who had mandibular osteotomies at the Queen Elizabeth Hospital, Birmingham, between March 2006 and April 2016. Questionnaires were collected at the final orthognathic postoperative appointment. The significance of the difference in QoL between those who had altered sensation of the lower lip and those who did not was compared using a two-tailed t test. During this period 170 patients had mandibular orthognathic operations. Completed questionnaires were received from 117 of those patients (69%) during this period, after a follow up of about six months. We found no significant difference between the perceived benefits of treatment between the 41 who had altered sensation and the 74 who did not (p=0.30). Only 5/41 who reported residual numbness six months postoperatively stated that they would not choose to have the same treatment again. In conclusion, orthognathic surgery results in an appreciable improvement in QoL and should continue to be funded by CCG in England. Contrary to the perception of some clinicians, those patients with residual numbness of the lip did not have significantly poorer QoL. Future interpretation of the data will be improved if they are collected both before and after the operation.

Autogenous bone remains the gold standard for augmentation of the alveolar ridge in congenital hypodontia and appreciable post-traumatic deformity. This generally reflects the volume of material required for such defects and the osteogenic potential of the grafts. Morbidity at the donor site and success rates may lead to autogenous grafts being superseded by xenografts or alloplastic materials in the future, but we know of little evidence to confirm this. All patients having augmentation of the alveolar ridge or sinus lift to enable subsequent placement of implants between 01 January 2009 and 31 December 2016 were identified from a prospectively-gathered database held at the Queen Elizabeth Hospital, Birmingham. Morbidity was recorded, with overall success defined as a graft that enabled subsequent placement of an implant. During this period the following grafts: calvarial (n=4), iliac crest (n=4), and ramus (n=149) were recorded, as well as 53 sinus lifts. Sinus lift augmentation with BioOss® had the highest success rate (51/53). Calvarial and iliac crest grafts had higher failure rates (2/4 and 3/4, respectively) than those from the mandibular ramus (6/149, 4%). Fifteen of 149 (10%) ramus grafts resulted in transient anaesthesia of the inferior alveolar nerve but no patients developed any permanent morbidity at the donor or recipient sites. Ramus grafts are a predictable method of bone augmentation with only transient morbidity at the donor site. Higher failure rates for extraoral grafts probably reflect their use in more challenging cases when more bone is required. Bilateral ramus grafts are an alternative to extraoral grafts and may be supplemented by bovine-derived particulate grafts with no appreciable increase in complications.

INTRODUCTION This aim of this study is to investigate the individual effects of varying concentrations of thrombin and fibrinogen on clot microstructure (characterised through the fractal dimension of the incipient clot network, df) and clot formation time (TGP) using a fibrin-thrombin clot model. df and TGP markers are measured using a haemorheological method that has already been investigated for whole blood. METHODS This is an in vitro study using three thrombin concentrations (0.1, 0.05 and 0.02 NIH/ml) and two fibrinogen concentrations (8 mg/ml and 12 mg/ml) to investigate a fibrin-thrombin clot model. The haemorheological changes were measured at the gel point using df and TGP. RESULTS Fractal dimension (df) increased with increasing concentrations of thrombin both at 8 mg/ml (1.60±0.024, 1.67±0.022, 1.74±0.079) and 12 mg/ml fibrinogen concentrations (1.63±0.02, 1.87±0.019, 1.95±0.014). On the other hand, TGP decreased for both 8 mg/ml (1089±265, 637±80, 223±22 seconds) and 12 mg/ml fibrinogen concentrations (2008±247, 776±20, 410±20 seconds). In contrast to previous studies investigating whole blood, TGP increased with higher fibrinogen levels. CONCLUSIONS The findings from this fibrin-thrombin clot model confirmed that df and TGP can detect changes in the incipient clot following manipulation of fibrinogen and thrombin concentration. df increases (indicating stronger clot) with higher concentrations of thrombin and fibrinogen. On the other hand, TGP decreased as expected with higher thrombin level but not with higher fibrinogen concentrations.

Mandibular condyle fractures are a common type of facial fracture in children. The authors aimed to examine the demographics, etiology, treatment, and outcomes of these fractures managed in a single pediatric trauma unit.A retrospective review was performed of patients presenting to a pediatric hospital between 2003 and 2016 with mandibular condyle fractures. Initial data was extracted from a dedicated trauma database. Included patient's medical records and imaging were then reviewed. Data on demographics, etiology, fracture type, and treatment were recorded. Univariate statistical analysis was performed.Forty-four patients with 49 condyle fractures were included. The average age of patients was 11.4 years (range 3-15 years). A fall from a bicycle/scooter was the most common mechanism. Twenty-six fractures were isolated and 23 involved a further fracture of the mandibular arch. The condylar neck was the most common site of fracture (55%). There was no statistical significance between age (0-10 years, 10-16 years) and site of fracture or the presence of an associated arch fracture. The majority of isolated fractures (73%) were treated conservatively without inter-maxillary fixation. Thirty-nine patients attended the follow-up and the median follow-up period was 196 days (interquartile range 21-165 days). Two patients had a malocclusion at follow-up that required intervention.There was a broad range of presentations in our cohort. Conservative management in isolated fractures resulted in stable outcomes and this large case series supports the consensus that management of pediatric condyle fractures should be as conservative as possible.

Burns are known to have an effect on coagulation in the early period after burn. Current coagulation tests have been criticised in acute burns due to their inherent limitations. This study aims to investigate the potential for a new quantitative functional biomarker of clot quality, fractal dimension, to identify changes in clot microstructure as a result of the burn inflammatory response and its treatment.A total of fifty-eight burn patients were included in this prospective case-controlled study. The control group (29 patients mean TBSA 1%), and case group (29 patients mean TBSA 30%) were compared at baseline and the case group investigated further over four time points (baseline, 12h, 24h and 5-7 days). Fractal analysis was performed, as well as current markers of coagulation, inflammatory markers and point-of-care tests, Thromboelastography and Multiplate analysis.Fractal dimension did not differ between groups at admission (1.73±0.06 and 1.72±0.1), and fell within the healthy index normal range (1.74±0.7), suggesting a normal clot microstructure in the early period after burn. Fractal dimension significantly reduced from baseline over the first 24h following injury (1.59±0.03 p0.005), indicating a significant reduction in mechanical clot strength and functionality consistent with a hypocoagulable state, not identified with other markers.This is the first study to quantify the changes in clot microstructure following burn injury. This study confirms clot microstructure is significantly altered during the first 24h after burn, with the production of a weaker, more porous fibrin clot, consistent with a hypocoagulable state.

Malignant infantile osteopetrosis (MIOP), an autosomal-recessive disorder, is extremely rare, presenting early in life with extreme sclerosis of the skeleton and reduced activity of osteoclasts. It was first described by Albers Schonberg in 1904. Disease manifestations include compensatory extramedullary haematopoiesis at sites such as the liver and spleen, hepatosplenomegaly, anaemia and thrombocytopaenia. Neurological manifestations can also occur due to narrowing of osseous foramina resulting in visual impairment, hearing loss, facial palsy and hydrocephalus. In addition, growth retardation and recurrent infections requiring long-term antibiotic use are common. The incidence of MIOP is 1/2 000 000 and if untreated, then it has a fatal outcome, with the majority of cases occurring within the first 5 years of life. At present, the only potentially curative option is a haematopoietic stem cell transplant. We present a 21-year-old woman, diagnosed with malignant infantile osteopetrosis, due to a mutation in the T-cell immune regulator 1 gene when aged 6 weeks, presenting with chronic osteomyelitis of her left mandible. As malignant infantile osteopetrosis has a high mortality in infancy, we felt it prudent to report this rare case in a patient surviving to adulthood.

It is important at the outset to distinguish the two main groups of vascular anomalies: vascular malformations and vascular tumours (e.g. haemangiomas). Vascular malformations are localized errors of angiogenic development, which should be distinguished from haemangiomas. They may involve any portion of the vascular system—arteries, veins, capillaries and lymphatics. Vascular malformations are therefore structural anomalies present at birth, which may or may not be clinically evident. Haemangiomas by contrast are tumorous growths, with increased endothelial cell proliferation as a distinguishing hallmark [1].

A methodology for fast determination of surface coverage of molecules or nanostructures assembled in monolayers at the surface of gold electrodes has been developed. The approach is based on anodic oxidative desorption of the molecules which is controlled by synchronized electrochemical gravimetric and voltammetric measurements. Successive anodic scans induce degradation and oxidative desorption of the assembled molecules resulting in a decrease in electrode mass. The completion of desorption is accurately controlled by the charge associated with adsorption of hydroxyl and oxygen species at the bare gold surface. The proposed method can be used to (i) complement the classical approaches or (ii) to estimate the surface coverage for nanostructures whose adsorption requirements, such as long-time assembling, ex-situ chemical treatment and other ex-situ or in-situ multistage procedures, complicate utilization of common approaches. Adsorbed nanostructures composed of poly(amido) amine dendrimers terminated with thiol functionalized viologen head groups were used as the model objects to evaluate the proposed methodology.

Anesthesia, critical illness, and trauma are known to alter thermoregulation, which can potentially affect coagulation and clinical outcome. This in vitro preclinical study explores the relationship between temperature change and hemostasis using a recently validated viscoelastic technique. We hypothesize that temperature change will cause significant alterations in the microstructural properties of clot.We used a novel viscoelastic technique to identify the gel point of the blood. The gel point identifies the transition of the blood from a viscoelastic liquid to a viscoelastic solid state. Furthermore, identification of the gel point provides 3 related biomarkers: the elastic modulus at the gel point, which is a measure of clot elasticity; the time to the gel point (TGP), which is a measure of the time required to form the clot; and the fractal dimension of the clot at the gel point, df, which quantifies the microstructure of the clot. The gel point measurements were performed in vitro on whole blood samples from 136 healthy volunteers over a temperature range of 27°C to 43°C.There was a significant negative correlation between increases in temperature, from 27°C to 43°C, and TGP (r = -0.641, P0.0005). Conversely, significant positive correlations were observed for both the elastic modulus at the gel point (r = 0.513, P = 0.0008) and df (r = 0.777, P0.0005) across the range of 27°C to 43°C. When temperature was reduced below 37°C, significant reductions in df and TGP occurred at ≤32°C (Bonferroni-corrected P = 0.0093) and ≤29°C (Bonferroni-corrected P = 0.0317), respectively. No significant changes were observed when temperature was increased to37°C.This study demonstrates that the gel point technique can identify alterations in clot microstructure because of changes in temperature. This was demonstrated in slower-forming clots with less structural complexity as temperature is decreased. We also found that significant changes in clot microstructure occurred when the temperature was ≤32°C.

Hyaluronic acid (HA) solutions represent an important class of biomedical products, mostly used in viscosupplementation of joints and as fillers. In the present work the hydrodynamic and rheological properties of hyaluronic acid, of differing MW(90-4000 kDa), in physiological saline were investigated. Firstly, the effective conformation taken by the polymer chains was studied using dynamic light scattering. It was observed that they behaved like random coils which dimension is higher increasing the molecular weight of the material. Secondly, combining a novel microrheological technique, based on the dynamic light scattering of tracer particles, with conventional rheometry, it was possible to study in which way the molecular weight and the concentration of the polymer influence the storage modulus (G’), loss modulus (G”) and complex viscosity (η*) of its solutions, over an extended frequency range (typically 0.01-10000 Hz). This extended characterization allowed determination of the mesh size ξ of the physical network, created by the entangled polymer chains. Calculated mesh sizes in the range 200-700 nm were observed, demonstrating the possibility to use these systems as injectable carriers of biomolecules with an appropriate dimension.

Polymers of intrinsic microporosity (PIMs) have been identified as potential next generation membrane materials for the separation of gas mixtures of industrial and environmental relevance. Based on the exceptionally rigid methanopentacene (MP) structural unit, a Polymer of Intrinsic Microporosity (PIM-MP-TB) was designed to demonstrate high selectivity for gasseparations. PIM-MP-TB was prepared using a polymerisation reaction involving the formation of Tröger’s base linking groups and demonstrated an apparent BET surface area of 743 m2 g-1 as a powder. The microporosity of PIM-MP-TB was also characterized by chain packing simulations. PIM-MP-TB proved soluble in chlorinated solvents and was cast as a robust, free-standing film suitable for gas permeation measurements. Despite lower gas permeability as compared to previously reported PIMs, high selectivities for industrially relevant gas pairs were obtained, surpassing the 2008 Robeson upper bound for H2/CH4 and O2/N2, (e.g., PO2=999 Barrer; αO2/N2= 5.0) and demonstrating a clear link between polymer rigidity and selectivity. Upon aging, the permeability data move parallel to the Robeson upper bounds with a decrease of permeability,compensated by a related increase in selectivity. Mixed gas permeation measurement for CO2/CH4 and CO2/N2 mixtures confirmed the excellent selectivity of PIM-MP-TB for potentially relevant separations such as biogas upgrading and CO2 capture from flue gas. Importantly, unlike other high perfoming PIMs, PIM-MP-TB is prepared in four simple steps from acheap starting material.

Drop-casting and inkjet printing are virtually the most versatile and cost-effective methods for depositing active materials on surfaces. However, drawbacks associated with the coffee-ring effect, as well as uncontrolled aggregation of the coating materials, have impeded the use of these methods for applications requiring high control of film properties. We now report on a simple method based on covalent cross-linking of monodisperse materials that enables the formation of thin films with homogeneous thicknesses and macroscale cohesion. The coffee-ring effect is impeded by triggering gelation of the coating materials via a thioacetate–disulfide transition which counterbalances the capillary forces induced by evaporation. Aggregates are prevented by monodisperse building blocks that ensure that the resulting gel resists sedimentation until complete droplet drying. This combined strategy yields an unprecedented level of homogeneity in the resulting film thickness in the 100 nm to 10 μm range. Moreover, macroscale cohesion is preserved as evidenced by the long-range charge transfer within the matrix. We highlight the impact of this method with bioelectrocatalysts for H2 and NADPH oxidation. Peak catalytic performances are reached at about 10-fold lower catalyst loading compared to conventional approaches owing to the high control on film cohesion and thickness homogeneity, thus setting new benchmarks in catalyst utilization.

Background Antithrombotics are the mainstay of management in coronary artery disease (CAD). However, no biomarker is available to assess their global effect on clot formation and structure. We validated a novel biomarker that measures clot microstructure, fractal dimension of incipient blood clot (df), in healthy volunteers, stroke, lung cancer and sepsis. Aims To validate df in both acute and stable CAD, and assess the effect of therapeutic intervention. Methods We prospectively recruited 2 groups: serial venous blood samples were collected on admission, after primary percutaneous coronary intervention (pPCI) and 24 hours in patients with STEMI, and a blood sample prior to angiography was obtained from 251 consecutive patients undergoing diagnostic coronary angiography. Patients were categorised based on angiographic findings as presence or absence of obstructive CAD (stenosis ≥50%). Results In 38 STEMI patients, df after pPCI was lower than df on admission (mean 1.631±0.063 vs 1.751±0.052, p Conclusions We characterise clot microstructure, as measured by df, in patients with STEMI and stable CAD. df can potentially be used to risk-stratify patients with stable CAD and assess the efficacy of therapeutic interventions by measuring changes in clot microstructure.

The main focus of this computational modelling study is to determine the extensional rheological response of sputum biofluids to provide a diagnostic tool (biomarker) for experimentally-based pathological analyses and clinical practice. This may be accomplished through advanced rheological parameterisation and characterisation of sputum samples, when considering extensional deformation flow situations that mimic sputum escalator deformation in the lung-airways. Sputum samples have been collected from patients (male and female, over fifty years of age) suffering from Chronic Obstructive Pulmonary Disease (COPD) at two stages of development: uninfected (stable or non-infective) state and infected (suffering exacerbations) state. Samples have been tested without any pre-treatment such as mechanical homogenisation. Experimental and numerical studies of Capillary Break-up Extensional Rheometer (CaBER) have been performed, from which comparison significant correlations are presented. Typically, the dynamic development of the mid-filament diameter is monitored during the process of necking and filament-failure (break-up). The aim is to link this type of data with that emerging from experimental/clinical trials to provide a biomarker revealing insight on state of disorder and resultant treatment. The rheology of sputum samples is represented through two rheological fluid modelling approaches: (i) a kinetic Single Extended pom–pom (SXPP) model and (ii) a time-dependent thixotropic Modified Bautista-Manero (MBM) model. These models are sufficiently rich to enable description of both network-structure and rheological properties, exhibiting viscoelastic response (memory), with strain-hardening/softening and shear-thinning properties.

Background Stroke is the second largest cause of death worldwide. Abnormalities in hemostasis play an important role in the pathophysiology of ischemic stroke (IS). These hemostatic defects can be detected using rotational thromboelastometry (ROTEM) as a global method of measuring coagulation.This study assessed the effects of IS on blood hypercoagulability using ROTEM method, before and subsequent to therapeutic interventions. Methods In a prospective observational cohort study, whole blood coagulation using ROTEM, along with full blood count and standard coagulation tests, were compared between patients with IS and an age-matched control group of healthy volunteers. Further assessment took place at 2-4 hours and at 24 hours in the stroke group after therapy to assess the effects of therapeutic intervention. Results Seventy-two patients with IS were age-matched to 71 healthy subjects. Clotting time (CT) INTEM (P = .01) and maximum clot firmness (MCF) INTEM (P = .02) were significantly different between stroke patients at baseline and healthy subjects, but this difference disappeared when controlled for by smoking status. There was no association between ROTEM parameters and time from stroke symptom onset or stroke severity as reflected in The National Institute of Health Stroke Scale score. Significant but small changes in the values of MCF-EXTEM, clot formation time (CFT) EXTEM, and alpha-EXTEM CT were observed after therapeutic intervention (thrombolysis or aspirin treatment). Conclusions ROTEM testing does not seem to detect a hypercoagulable state in patients with IS. Nonetheless, some ROTEM parameters had a small change after antiplatelet therapy or thrombolysis.

Background The rheological properties of sputum may influence lung function and become modified in disease. Objective This study aimed to correlate the viscoelastic properties of sputum with clinical data on the severity of disease in patients with chronic obstructive pulmonary disease (COPD). Methods Sputum samples from COPD patients were investigated using rheology, simple mathematical modelling and Scanning Electron Microscopy (SEM). The samples were all collected from patients within two days of their admission to Prince Philip Hospital due to an exacerbation of their COPD. Oscillatory and creep rheological techniques were used to measure changes in viscoelastic properties at different frequencies over time. Results COPD sputum was observed to behave as a viscoelastic solid at all frequencies studied. Comparing the rheology of exacerbated COPD sputum with healthy sputum (not diagnosed with a respiratory disease) revealed significant differences in response to oscillatory shear and creep-recovery experiments, which highlights the potential clinical benefits of better understanding sputum viscoelasticity. A common power law model G(t)=G0(tτ0)-m was successfully fitted to experimental rheology data over the range of frequencies studied. Conclusions A comparison between clinical data and the power law index m obtained from rheology, suggested that an important possible future application of this parameter is as a potential biomarker for COPD severity.

In this study, pulped cellulose fibres were pre-treated with aqueous morpholine prior to mechanical disruption in the production of cellulose nanofibrils (CNF). The properties of the morpholine pre-treated CNF (MCNF) were closely compared with CNF obtained from carboxymethylation (CMCNF) and TEMPO-oxidation (TCNF) pre-treatment methods. An investigation of the swelling behaviours of cellulose in varying concentrations of morpholine revealed that there is a synergistic behaviour between morpholine and water in its ability to swell cellulose. As a result, cellulose pulp dispersed in 1:1 mole ratio of morpholine to water was well swollen and readily fibrillated by mechanical shear. Surface chemistry analyses indicated that the surface of the MCNF remained unmodified, compared to the CMCNF and TCNF which were modified with anionic groups. This resulted in only a slight decrease in crystallinity index and a minimal effect on the thermal stability of MCNF, compared to CMCNF and TCNF which showed marked decreases in crystallinity indices and thermal stabilities. The average widths of MCNF, CMCNF and TCNF, as measured from electron microscopic images, were broadly similar. The higher polydispersity of MCNF widths however led to a differential sedimentation and subsequent lower aspect ratio in comparison with CMCNF and TCNF as estimated using the sedimentation approach. Also, the presence of electrostatic repulsive forces, physical interactions/entanglements and lower rigidity threshold of the CMCNF and TCNF resulted in higher storage moduli compared to the MCNF, whose elasticity is controlled by physical interactions and entanglements. Aqueous morpholine pre-treatment can potentially be regarded as an ecologically sustainable process for unmodified CNF production, since the chemical reagent is not consumed and can be recovered and reused.

In this study, the aspect ratios of carboxymethylated and TEMPO-oxidised cellulose nanofibrils (CNF) were estimated by gel point analysis using a sedimentation approach. The flocculation and subsequent sedimentation of the CNF aqueous suspensions, which were stabilised by negative repulsive forces, were made possible after screening in concentrated salt media. The aspect ratios of the CNFs were then calculated from the linear fit (gel point) of the plot of concentration of the CNFs against the relative sediment height, using the crowding number theory.

Despite the interwoven nature of platelet activation and the coagulation system in thrombosis, few studies relate both analysis of protein and cellular parts of coagulation in the same population. In the present study, we use matched ex vivo samples to determine the influences of standard antiplatelet therapies on platelet function and use advanced rheological analyses to assess clot formation. Healthy volunteers were recruited following fully informed consent then treated for 7 days with single antiplatelet therapy of aspirin (75 mg) or prasugrel (10 mg) or with dual antiplatelet therapy (DAPT) using aspirin (75 mg) plus prasugrel (10 mg) or aspirin (75 mg) plus ticagrelor (90 mg). Blood samples were taken at day 0 before treatment and at day 7 following treatment. We found that aspirin plus prasugrel or aspirin plus ticagrelor inhibited platelet responses to multiple agonists and reduced P-selectin expression. Significant platelet inhibition was coupled with a reduction in fractal dimension corresponding to reductions in mean relative mass both for aspirin plus prasugrel (-35 ± 16% change, p = 0.04) and for aspirin plus ticagrelor (-45 ± 14% change, p = 0.04). Aspirin alone had no effect upon measures of clot structure, whereas prasugrel reduced fractal dimension and mean relative mass. These data demonstrate that platelets are important determinants of clot structure as assessed by fractal dimension (df) and that effective platelet inhibition is associated with a weaker, more permeable fibrin network. This indicates a strong association between the therapeutic benefits of antiplatelet therapies and their abilities to reduce thrombus density that may be useful in individual patients to determine the functional relationship between platelet reactivity, eventual clot quality, and clinical outcome. df could represent a novel risk stratification biomarker useful in individualizing antiplatelet therapies.

Background Coronary artery disease (CAD) is associated with an increased prothrombotic tendency and is also linked to unfavourably altered clot microstructure. We have previously described a biomarker of clot microstructure (d f ) that is unfavourably altered in acute myocardial infarction. The d f biomarker assesses whether the blood will form denser or looser microstructures when it clots. In this study we assessed in patients with stable chest pain whether d f can differentiate between obstructed and unobstructed CAD. Methods A blood sample prior to angiography was obtained from 251 consecutive patients undergoing diagnostic coronary angiography. Patients were categorised based on angiographic findings as presence or absence of obstructive CAD (stenosis ≥50%). The blood sample was assessed using the d f biomarker, standard laboratory markers and platelet aggregometry (Multiplate). Results A significant difference (p=0.028) in d f was observed between obstructive CAD (1.748±0.057, n=83) and unobstructive CAD (1.732±0.052, n=168), where patients with significant CAD produce denser, more tightly packed clots. d f was also raised in men with obstructive CAD compared with women (1.745±0.055 vs 1.723±0.052, p=0.007). Additionally d f significantly correlated with the platelets response to arachidonic acid as measured by the ASPItest area under the curve readings from platelet aggregometry (correlation coefficient=0.166, p=0.008), a low value of the ASPItest indicating effective aspirin use was associated with looser, less dense clots. Conclusions For the first time, we characterise clot microstructure, as measured by d f , in patients with stable CAD. d f can potentially be used to risk-stratify patients with stable CAD and assess the efficacy of therapeutic interventions by measuring changes in clot microstructure.

Hydrogenases are nature's efficient catalysts for both the generation of energy via oxidation of molecular hydrogen and the production of hydrogen via the reduction of protons. However, their O2 sensitivity and deactivation at high potential limit their applications in practical devices, such as fuel cells. Here, we show that the integration of an O2-sensitive hydrogenase into a specifically designed viologen-based redox polymer protects the enzyme from O2 damage and high-potential deactivation. Electron transfer between the polymer-bound viologen moieties controls the potential applied to the active site of the hydrogenase and thus insulates the enzyme from excessive oxidative stress. Under catalytic turnover, electrons provided from the hydrogen oxidation reaction induce viologen-catalysed O2 reduction at the polymer surface, thus providing self-activated protection from O2. The advantages of this tandem protection are demonstrated using a single-compartment biofuel cell based on an O2-sensitive hydrogenase and H2/O2 mixed feed under anode-limiting conditions.