Measurement of isoniazid in tuberculosis patients using finger sweat with creatinine normalisation: A controlled administration study.

BACKGROUND: Insufficient exposure and poor compliance with anti-tuberculosis (TB) medications are risk factors for treatment failure and the development of drug resistance. Measurement of drugs in biological samples, such as blood and saliva, can be used to assess adherence and make dose adjustments by therapeutic drug monitoring (TDM). Finger sweat testing is a convenient and non-invasive method to monitor patients. OBJECTIVES: To assess the feasibility of finger sweat testing for medication adherence and as a semi-quantitative tool for TDM analysis. METHODS: Ten patients provided finger sweat, blood and saliva samples following a controlled dose of isoniazid. Samples were analysed by liquid chromatography-mass spectrometry. RESULTS: Isoniazid can be detected in finger sweat 1-6 h following administration at typically prescribed dosages. The normalisation of isoniazid to creatinine increases the correlation between finger sweat and serum isoniazid concentration and provides a means to account for inconsistent sample volumes. CONCLUSION: We describe the time-course measurement of isoniazid (or drug-to-creatinine ratio) in finger sweat compared to the pharmacokinetic profile in blood for the first time. This technique, adaptable for other drugs, could reduce the burden on clinics and improve patient experience.

Engagement of a community advisory group to shape and build up participation in TB research.

It is essential that communities at risk from TB are involved in TB research. Community advisory groups (CAGs) are one mechanism for involving communities in research and creating platforms for discussions between researchers and community members. We organised a CAG meeting with community members and people with lived experience in Ho Chi Minh City, Vietnam, to explore the community's knowledge about TB and their perspectives on different diagnostic tests in Vietnam, a low-middle-income country with a high TB burden. Researchers shared basic information and addressed questions about TB. CAG members commented on preference of TB screening tests, and suggested that chest X-rays and blood tests were more acceptable than sputum tests because of the difficulty in sputum expectoration. In addition, clinical studies that required fewer visits to the hospitals would be preferred, even if this meant a greater reliance on blood sampling.

Il est essentiel que les communautés exposées au risque de TB soient impliquées dans la recherche sur la TB. Les groupes consultatifs communautaires (CAG, pour l'anglais « community advisory groups ¼) constituent un mécanisme permettant d'impliquer les communautés dans la recherche et de créer des plateformes de discussion entre les chercheurs et les membres de la communauté. Nous avons organisé une réunion du CAG avec des membres de la communauté et des personnes ayant une expérience vécue à Ho Chi Minh Ville, au Viêt Nam, afin d'explorer les connaissances de la communauté sur la TB et leurs perspectives sur les différents tests de diagnostic au Viêt Nam, un pays à revenu faible et moyen où la charge de la TB est élevée. Les chercheurs ont partagé des informations de base et répondu à des questions sur la TB. Les membres du CAG ont fait part de leur préférence pour les tests de dépistage de la TB et ont suggéré que les radiographies pulmonaires et les analyses de sang étaient plus acceptables que les tests d'expectoration en raison de la difficulté d'expectoration des crachats. En outre, les études cliniques qui nécessitent moins de visites dans les hôpitaux seraient préférées, même si cela implique une plus grande dépendance à l'égard des prélèvements sanguins.

A case of traumatic uterine avulsion in pregnancy.

Complete uterine avulsion is an extremely rare complication of trauma sustained during pregnancy. We present the case of a 21-year-old nullipara at 16 weeks' gestation who was involved in a high-speed motor vehicle collision with subsequent fetal demise. Initially she was hemodynamically stable and demonstrated small amounts of intraabdominal free fluid, therefore multidisciplinary conservative measures were undertaken. However, as her condition worsened, she was taken for exploratory laparotomy, revealing complete gravid uterine avulsion at the level of the cervicoisthmic junction. Due to hemodynamic instability and concerns for retroperitoneal bleeding, a supracervical hysterectomy was performed. Although a rare occurrence, our case demonstrates the need for a high level of suspicion for uterine avulsion in certain cases of trauma in pregnancy. This highlights the false reassurance provided by stable vitals in a pregnant patient that may mask ongoing bleeding and development of hemorrhagic shock, the importance of interpreting different imaging modalities together when the cause of instability is unclear, and the utility of a multidisciplinary approach. While our patient underwent hysterectomy due to hemodynamic instability, it is unknown whether earlier investigation with laparoscopy to confirm uterine integrity may have circumvented this and allowed for fertility-sparing management. As such, our case encourages the utilization of early diagnostic laparoscopy if there is concern for uterine avulsion for the consideration of alternative surgical interventions for management.

Noninvasive drug adherence monitoring of antipsychotic patients via finger sweat testing.

Collection of finger sweat is explored here as a rapid and convenient way of monitoring patient adherence to antipsychotic drugs. Finger sweat samples (n = 426) collected from patients receiving treatment with clozapine, quetiapine and olanzapine were analysed by liquid chromatography mass spectrometry, including a subgroup of patients with paired plasma samples. Finger sweat samples were also analysed from a negative control group and patients who had handled antipsychotic medication only. The finger sweat test (based on the detection of parent drug in one donated sample) was 100% effective in monitoring adherence within commonly prescribed dosing ranges. In comparison to participants who handled the medication only, the test could distinguish between contact and administration through monitoring of the drug metabolite, or the level of parent drug. Additionally, in a subgroup of patients prescribed clozapine, a statistically significant correlation was observed between the mass of parent drug in finger sweat and plasma concentration. The finger sweat technology shows promise as a dignified, noninvasive method to monitor treatment adherence in patients taking antipsychotics.

Inter-Rater Reliability and Correlation of L1 Hounsfield Unit Measurements with DXA Scores.

INTRODUCTION: While prior studies have generally reported rigorous protocols using prespecified CT scanner settings for HU measurements, the present study sought to report on the correlation between DXA and HUs recorded using several CT scanners with varying sequences, simulating measurements performed in "real-world" hospital and Emergency Department (ED) settings. METHODOLOGY: Six raters performed HU measurements of trabecular bone at the L1 vertebral body for forty consecutive patients on Phillips and General Electric (GE) abdominal CT scans obtained between 2017 and 2021. Inter-rater reliability of the HU measurements and their correlations with recorded DXA-based bone assessments were determined. Correlation coefficients were calculated for the HU measurements between scanner vendors as well as for the CT HUs with each DXA measurement. RESULTS: The ICC for L1 HUs read on the Phillips and GE scanners were 0.85 and 0.82, respectively, indicating excellent agreement. The correlation coefficient for the mean HUs on the Phillips and GE scanners was 0.92, also indicating excellent correlation. For both scanner vendors, the HU values most closely correlated with the total femur and femoral neck T-scores. CONCLUSIONS: HU values recorded on a Phillips and GE scanner both demonstrated excellent inter-rater reliability. Correlations were strongest between L1 HU values and total femur DXA T-scores. Readily available abdominal CT image data across multiple hospital settings can be utilized by providers of varying level of imaging interpretation expertise to determine vertebral body Hounsfield units that may help identify osteoporosis risk without additional radiation exposure or cost.

Clinical advances in oncolytic virotherapy for pediatric brain tumors.

Malignant brain tumors constitute nearly one-third of cancer diagnoses in children and have recently surpassed hematologic malignancies as the most lethal neoplasm in the pediatric population. Outcomes for children with brain tumors are unacceptably poor and current standards of care-surgical resection, chemotherapy, and radiation-are associated with significant long-term morbidity. Oncolytic virotherapy has emerged as a promising immunotherapy for the treatment of brain tumors. While the majority of brain tumor clinical trials utilizing oncolytic virotherapy have been in adults, five viruses are being tested in pediatric brain tumor clinical trials: herpes simplex virus (G207), reovirus (pelareorep/Reolysin), measles virus (MV-NIS), poliovirus (PVSRIPO), and adenovirus (DNX-2401, AloCELYVIR). Herein, we review past and current pediatric immunovirotherapy brain tumor trials including the relevant preclinical and clinical research that contributed to their development. We describe mechanisms by which the viruses may overcome barriers in treating pediatric brain tumors, examine challenges associated with achieving effective, durable responses, highlight unique aspects and successes of the trials, and discuss future directions of immunovirotherapy research for the treatment of pediatric brain tumors.

Eight-month repellency and efficacy of an imidacloprid/flumethrin (Seresto® ) collar against the eastern paralysis tick (Ixodes holocyclus) on cats.

OBJECTIVE: The objective of this study was to determine the repellency and efficacy of a 10% imidacloprid/4.5% flumethrin (Seresto® , Elanco) collar over an 8-month period against the eastern paralysis tick (Ixodes holocyclus) on cats. METHODS: Two non-blinded, open gender, randomised, placebo-controlled pen studies were conducted, with 26 cats enrolled in each study. Prior to inclusion, cats were immunised with I. holocyclus holocyclotoxin. Cats were treated on Day 0 with either an imidacloprid/flumethrin or placebo collar. Tick infestations with 20 unfed adult female eastern paralysis ticks commenced on Day 7, and were repeated monthly for 8 months. Repellency was determined by comparing the mean number of attached ticks on imidacloprid/flumethrin treated cats, to placebo collar treated cats at 6 and 24 h post infestation. Efficacy was determined by comparing the mean number of live ticks on imidacloprid/flumethrin collar treated cats to placebo collar treated cats at 72 h post infestation. RESULTS: Efficacy was 100% (P < 0.001) at 72 h, and repellency was greater than 96% (P < 0.001) at 24 h for every tick challenge in each of the two studies, from Day 7 to the final infestation at 8 months for imidacloprid/flumethrin collar treated cats. CONCLUSIONS: In two pen studies, an imidacloprid/flumethrin collar controlled and repelled the eastern paralysis tick (I. holocyclus) on cats for 8-months. The marked repellency effect in addition to controlling tick paralysis would be beneficial in preventing tick bites and their sequelae.

Measuring therapeutic engagement in acute mental health inpatient environments: the perspectives of service users and mental health nurses.

BACKGROUND: A key component of caring for service users (SUs) in acute mental health inpatient environments is Therapeutic Engagement (TE). To that end, the Therapeutic Engagement Questionnaire (TEQ) was developed and validated. The TEQ measures TE between SUs and registered mental health nurses (RMHNs) from the perspective of both parties and can quantify and recognise how nurses engage with SUs and monitor this activity as well as its enhancement of SU care and recovery. The aim of this study was to explore the views of SUs and RMHNs in relation to the TEQ and how it could be adopted into clinical practice within an acute inpatient environment. METHODS: As part of the validation stage of the development of the TEQ, the views of 628 SUs and 543 RMHNs were collected using a qualitative approach by way of free text at the end of the questionnaire. Two questions required free text response: - 'what do you think of the TEQ?', and 'how can it be utilised?' RESULTS: Following thematic analysis, it was found that both sets of participants stated that such a tool could be utilised to improve the service, could help nurses with reflective practice, be utilised as part of clinical supervision and to aid nurses' professional development. The nurse participants also stated that such a tool would help track SU participation and enablement in their care. Furthermore, the nurses noted that the tool would help to reinforce the core 'caring' value of nursing and the overall goal of recovery. The SUs added that the TEQ would recognise the work of mental health nurses and provide them with a clear opportunity to express their views in relation to nursing staff. CONCLUSIONS: Therapeutic engagement (TE) has been identified as part of the repertoire of mental health nursing and both groups of participants identified how a tool to assess this construct may be utilised in day-to-day clinical practice to the benefit of each group.

Evaluation of immunologic parameters in canine glioma patients treated with an oncolytic herpes virus.

Aim: To molecularly characterize the tumor microenvironment and evaluate immunologic parameters in canine glioma patients before and after treatment with oncolytic human IL-12-expressing herpes simplex virus (M032) and in treatment naïve canine gliomas. Methods: We assessed pet dogs with sporadically occurring gliomas enrolled in Stage 1 of a veterinary clinical trial that was designed to establish the safety of intratumoral oncoviral therapy with M032, a genetically modified oncolytic herpes simplex virus. Specimens from dogs in the trial and dogs not enrolled in the trial were evaluated with immunohistochemistry, NanoString, Luminex cytokine profiling, and multi-parameter flow cytometry. Results: Treatment-naive canine glioma microenvironment had enrichment of Iba1 positive macrophages and minimal numbers of T and B cells, consistent with previous studies identifying these tumors as immunologically "cold". NanoString mRNA profiling revealed enrichment for tumor intrinsic pathways consistent with suppression of tumor-specific immunity and support of tumor progression. Oncolytic viral treatment induced an intratumoral mRNA transcription signature of tumor-specific immune responses in 83% (5/6) of canine glioma patients. Changes included mRNA signatures corresponding with interferon signaling, lymphoid and myeloid cell activation, recruitment, and T and B cell immunity. Multiplexed protein analysis identified a subset of oligodendroglioma subjects with increased concentrations of IL-2, IL-7, IL-6, IL-10, IL-15, TNFα, GM-CSF between 14 and 28 days after treatment, with evidence of CD4+ T cell activation and modulation of IL-4 and IFNγ production in CD4+ and CD8+ T cells isolated from peripheral blood. Conclusion: These findings indicate that M032 modulates the tumor-immune microenvironment in the canine glioma model.

The One Health Consortium: Design of a Phase I Clinical Trial to Evaluate M032, a Genetically Engineered HSV-1 Expressing IL-12, in Combination With a Checkpoint Inhibitor in Canine Patients With Sporadic High Grade Gliomas.

As the most common and deadly of primary brain tumors, malignant gliomas have earned their place within one of the most multifaceted and heavily-funded realms of medical research. Numerous avenues of pre-clinical investigation continue to provide valuable insight, but modeling the complex evolution and behavior of these tumors within a host under simulated circumstances may pose challenges to extrapolation of data. Remarkably, certain breeds of pet dogs spontaneously and sporadically develop high grade gliomas that follow similar incidence, treatment, and outcome patterns as their human glioma counterparts. The most malignant of these tumors have been refractory to limited treatment options despite aggressive treatment; outcomes are dismal with median survivals of just over 1 year in humans and 2 months in dogs. Novel treatments are greatly needed and combination therapies appear to hold promise. This clinical protocol, a dose-escalating phase I study in dogs with sporadic malignant glioma, represents a first in comparative oncology and combination immunotherapy. The trial will evaluate M032, an Interleukin-12 expressing Herpes Simplex virus, alone and combined with a checkpoint inhibitor, Indoximod. Extensive pre-clinical work has demonstrated safety of intracranial M032 administration in mice and non-human primates. M032 is currently being tested in humans with high-grade malignant gliomas. Thus, in a novel fashion, both canine and human trials will proceed concurrently allowing a direct "head-to-head" comparison of safety and efficacy. We expect this viral oncolytic therapy to be as safe as it is in human patients and M032 to (a) infect and kill glioma cells, producing a virus and tumor cell antigen-rich debris field; (b) provide an adjuvant effect due to liberation of viral DNA, which is rich in unmethylated CpG sequences that "toggle" TLR-9 receptors; and (c) express IL-12 locally, stimulating induction of TH1 lymphocytes. The resultant immune-mediated anti-viral responses should, through cross-epitope spreading, translate into a strong response to tumor antigens. The ability to compare human and dog responses in real time affords the most stringent test of suitability of the dog as an informative model of human brain tumors. Subsequent studies will allow canine trials to properly inform the design of human trials.

Discovery of ONO-8590580: A novel, potent and selective GABAA α5 negative allosteric modulator for the treatment of cognitive disorders.

The identification and SAR development of a series of negative allosteric modulators of the GABAA α5 receptor is described. This novel series of compounds was optimised to provide analogues with high GABAA α5 binding affinity, high α5 negative allosteric modulatory activity, good functional subtype selectivity and low microsomal turnover, culminating in identification of ONO-8590580.

Impact of exercise on bone mineral density, fall prevention, and vertebral fragility fractures in postmenopausal osteoporotic women.

Osteoporosis is the most prevalent bone disease worldwide and predisposes affected individuals to fragility fractures. Exercise has been shown to have multiple health benefits in post-menopausal osteoporotic women, but often recommendations regarding the benefits of specific exercise types are vague. Improving bone mineral density (BMD) is an essential component in any program to prevent osteoporotic vertebral fractures. The objective of this report is to briefly review the current understanding on the impact of exercise on BMD in postmenopausal women as it pertains to fragility fractures. Broad categories of exercises include aerobic, resistance, stretching, and balance. Tai Chi, Yoga, and Pilates are a heterogeneous group of specific exercise modalities that can span multiple categories. Current literature suggests that only resistance type exercises have a convincing impact on BMD. Core-strengthening exercises and attention to posture/balance can help mitigate falls. A number of barriers affect patient compliance and accessibility to exercise. In summary, exercise should be included in any multi-modality osteoporosis treatment plan with the goal of sustained exercise throughout life. If possible, osteoporotic women should be on a resistance-based regimen incorporating weight-bearing exercises, and also target posture and balance. Healthcare providers and educators should have resources readily available for patients.

Topical wound anaesthesia: efficacy to mitigate piglet castration pain.

OBJECTIVE: There is a critical need for safe and effective analgesic treatments to address pain resulting from surgical husbandry procedures in livestock. Piglet castration results in acute pain and stress to the animal; however, it is performed globally on millions of piglets annually, often without any analgesia what-so-ever. Tri-Solfen® (Animal Ethics Pty Ltd, Yarra Glen, Victoria, Australia) is a combination local anaesthetic and antiseptic formulation which, applied topically to wounds, has proven effective, and is registered for use to alleviate pain associated with castration (and other wounds) in lambs and calves in Australia and New Zealand. It is also reported to be effective to reduce pain in piglets following castration. DESIGN: This randomised, blinded, placebo-controlled study examined the safety and efficacy of the formulation, administered via an adapted wound instillation method, to control pain both during and following piglet castration. METHOD: Piglets received Tri-Solfen or placebo, instilled to the wound immediately following skin incision. A 30 s wait period was then observed prior to completing castration. Pain mitigation was assessed by grading nociceptive resistance movements and piglet vocal response during castration, as well as by grading response to mechanical sensory stimulation of the wound (von Frey and needlestick) following castration. RESULTS: There was a significant reduction in nociceptive motor and vocal response during castration and in response to mechanical sensory wound stimulation up to and including 2 h following castration. There were no adverse events. CONCLUSION: Administered via this method, Tri-Solfen is effective to mitigate acute peri-operative castration pain in piglets.

Repeat gamma knife stereotactic radiosurgery in the treatment of trigeminal neuralgia: A single-center experience and focused review of the literature.

OBJECTIVES: Repeat Gamma Knife stereotactic radiosurgery (GKSR) for refractory trigeminal neuralgia (TGN) is an increasingly common practice. Prior studies have reported varying success rates and incidence of trigeminal nerve dysfunction following repeated GKSR. We report treatment outcomes and toxicity in patients following repeat GKSR for TGN at the University of Alabama at Birmingham (UAB) with a focused review of the literature. METHODS: We retrospectively reviewed medical records of 55 TGN patients re-treated with radiosurgery using the Leksell Gamma Knife® at the University of Alabama at Birmingham between 1996 and 2012. Outcomes were defined using the Modified Marseille Scale. Demographics, prior treatments and symptom duration were correlated with outcomes. RESULTS: Eighteen patients (33%) achieved Marseille Class I or II, 14 (25%) Class III or IV, and 23 (42%) Class V at a mean follow-up of 14.4 months. Twenty-five patients (45%) developed new trigeminal nerve dysfunction after re-treatment. Of these, four (16%) did not develop dysfunction until subsequent microvascular decompression (MVD) for inadequate symptom relief. CONCLUSIONS: Although more than half of the patients undergoing repeat GKSR for refractory TGN maintained excellent or good outcomes (Marseille classes I-IV) at an average follow-up of 14.4 months, neither age, gender, nor pre-treatment duration of symptoms or interval between treatments had a statistically significant effect on outcomes. Following repeat GKSR, patients have increased risk for new-onset trigeminal nerve dysfunction and those undergoing MVD after repeat GKSR may have an increased risk for new-onset trigeminal nerve dysfunction.

Prospective and Multicenter Evaluation of Outcomes for Quality of Life and Activities of Daily Living for Balloon Kyphoplasty in the Treatment of Vertebral Compression Fractures: The EVOLVE Trial.

BACKGROUND: Osteoporotic and neoplastic vertebral compression fractures (VCF) are common and painful, threatening quality of life and increasing risk of morbidity and mortality. Balloon kyphoplasty is a percutaneous option for treating painful cancer- and osteoporosis-related VCFs, supported by 2 randomized trials demonstrating efficacy benefits of BKP over nonsurgical care. OBJECTIVE: To investigate 12-mo disability, quality of life, and safety outcomes specifically in a Medicare-eligible population, representing characteristic patients seen in routine clinical practice. METHODS: A total of 354 patients with painful VCFs were enrolled at 24 US sites with 350 undergoing kyphoplasty. Four coprimary endpoints-Numerical Rating Scale (NRS) back pain, Oswestry Disability Index (ODI), Short Form-36 Questionnaire Physical Component Summary (SF-36v2 PCS), EuroQol-5-Domain (EQ-5D)-were evaluated for statistically significant improvement 3 mo after kyphoplasty. Data were collected at baseline, 7 d, and 1, 3, 6, and 12 mo (www.clinicaltrials.gov registration NCT01871519). RESULTS: At the 3-mo primary endpoint, NRS improved from 8.7 to 2.7 and ODI improved from 63.4 to 27.1; SF-36 PCS was 24.2 at baseline improving to 36.6, and EQ-5D improved from 0.383 to 0.746 (P < .001 for each). These outcomes were statistically significant at every follow-up time point. Five device-/procedure-related adverse events, intraoperative asymptomatic balloon rupture, rib pain, and aspiration pneumonia, and a new VCF 25 d postprocedure, and myocardial infarction 105 d postprocedure were reported and each resolved with proper treatment. CONCLUSION: This large, prospective, clinical study demonstrates that kyphoplasty is a safe, effective, and durable procedure for treating patients with painful VCF due to osteoporosis or cancer.

Management of vertebral fragility fractures: a clinical care pathway developed by a multispecialty panel using the RAND/UCLA Appropriateness Method.

BACKGROUND CONTEXT: Vertebral fragility fractures (VFFs), mostly due to osteoporosis, are very common and are associated with significant morbidity and mortality. There is a lack of consensus on the appropriate management of patients with or suspected of having a VFF. PURPOSE: This work aimed at developing a comprehensive clinical care pathway (CCP) for VFF. STUDY DESIGN/SETTING: The RAND/UCLA Appropriateness Method was used to develop patient-specific recommendations for the various components of the CCP. The study included two individual rating rounds and two plenary discussion sessions. METHODS: A multispecialty expert panel (orthopedic and neurosurgeons, interventional [neuro]radiologists and pain specialists) assessed the importance of 20 signs and symptoms for the suspicion of VFF, the relevance of 5 diagnostic procedures, the appropriateness of vertebral augmentation versus nonsurgical management for 576 clinical scenarios, and the adequacy of 6 aspects of follow-up care. RESULTS: The panel identified 10 signs and symptoms believed to be relatively specific for VFF. In patients suspected of VFF, advanced imaging was considered highly desirable, with MRI being the preferred diagnostic modality. Vertebral augmentation was considered appropriate in patients with positive findings on advanced imaging and in whom symptoms had worsened and in patients with 2 to 4 unfavorable conditions (eg, progression of height loss and severe impact on functioning), dependent on their relative weight. Time since fracture was considered less relevant for treatment choice. Follow-up should include evaluation of bone mineral density and treatment of osteoporosis. CONCLUSIONS: Using the RAND/UCLA Appropriateness Method, a multispecialty expert panel established a comprehensive CCP for the management of VFF. The CCP may be helpful to support decision-making in daily clinical practice and to improve quality of care.

Quantitative interferon-gamma responses predict future disease progression in badgers naturally infected with Mycobacterium bovis.

The diagnosis and control of Mycobacterium bovis infection (bovine tuberculosis: TB) continues to present huge challenges to the British cattle industry. A clearer understanding of the magnitude and duration of immune response to M. bovis infection in the European badger (Meles meles) - a wildlife maintenance host - may assist with the future development of diagnostic tests, and vaccination and disease management strategies. Here, we analyse 5280 diagnostic test results from 550 live wild badgers from a naturally-infected population to investigate whether one diagnostic test (a gamma interferon release [IFNγ] assay, n = 550 tests) could be used to predict future positive results on two other tests for the same disease (a serological test [n = 2342 tests] and mycobacterial culture [n = 2388 tests]) and hence act as an indicator of likely bacterial excretion or disease progression. Badgers with the highest IFNγ optical density (OD) values were most likely to subsequently test positive on both serological and culture tests, and this effect was detectable for up to 24 months after the IFNγ test. Furthermore, the higher the original IFNγ OD value, the greater the chance that a badger would subsequently test positive using serology. Relationships between IFNγ titres and mycobacterial culture results from different types of clinical sample suggest that the route of infection may affect the magnitude of immune response in badgers. These findings identify further value in the IFNγ test as a useful research tool, as it may help us to target studies at animals and groups that are most likely to succumb to more progressive disease.

The structural basis for the functional comparability of factor VIII and the long-acting variant recombinant factor VIII Fc fusion protein.

Essentials Recombinant factor VIII (rFVIII) Fc fusion protein has a 1.5-fold longer half-life than rFVIII. Five orthogonal methods were used to characterize the structure of rFVIIIFc compared to rFVIII. The C-terminal Fc fusion does not perturb the structure of FVIII in rFVIIIFc. The FVIII and Fc components of rFVIIIFc are flexibly tethered and functionally independent. SUMMARY: Background Fusion of the human IgG1 Fc domain to the C-terminal C2 domain of B-domain-deleted (BDD) factor VIII (FVIII) results in the recombinant FVIII Fc (rFVIIIFc) fusion protein, which has a 1.5-fold longer half-life in humans. Objective To assess the structural properties of rFVIIIFc by comparing its constituent FVIII and Fc elements with their respective isolated components, and evaluating their structural independence within rFVIIIFc. Methods rFVIIIFc and its isolated FVIII and Fc components were compared by the use of hydrogen-deuterium exchange mass spectrometry (HDX-MS). The structure of rFVIIIFc was also evaluated by the use of X-ray crystallography, small-angle X-ray scattering (SAXS), and electron microscopy (EM). The degree of steric interference by the appended Fc domain was assessed by EM and surface plasmon resonance (SPR). Results HDX-MS analysis of rFVIIIFc revealed that fusion caused no structural perturbations in FVIII or Fc. The rFVIIIFc crystal structure showed that the FVIII component is indistinguishable from published BDD FVIII structures. The Fc domain was not observed, indicating high mobility. SAXS analysis was consistent with an ensemble of rigid-body models in which the Fc domain exists in a largely extended orientation relative to FVIII. Binding of Fab fragments of anti-C2 domain antibodies to BDD FVIII was visualized by EM, and the affinities of the corresponding intact antibodies for BDD FVIII and rFVIIIFc were comparable by SPR analysis. Conclusions The FVIII and Fc components of rFVIIIFc are structurally indistinguishable from their isolated constituents, and show a high degree of structural independence, consistent with the functional comparability of rFVIIIFc and unmodified FVIII.

Lysophosphatidic acid provides a missing link between osteoarthritis and joint neuropathic pain.

OBJECTIVE: Emerging evidence suggests that osteoarthritis (OA) has a neuropathic component; however, the identity of the molecules responsible for this peripheral neuropathy is unknown. The aim of this study was to determine the contribution of the bioactive lipid lysophosphatidic acid (LPA) to joint neuropathy and pain. DESIGN: Male Lewis rats received an intra-articular injection of 50 µg of LPA into the knee and allowed to recover for up to 21 days. Saphenous nerve myelination was assessed by g-ratio calculation from electron micrographs and afferent nerve damage visualised by activation transcription factor-3 (ATF-3) expression. Nerve conduction velocity was measured electrophysiologically and joint pain was determined by hindlimb incapacitance. The effect of the LPA antagonist Ki-16425 was also evaluated. Experiments were repeated in the sodium monoiodoacetate (MIA) model of OA. RESULTS: LPA caused joint nerve demyelination which resulted in a drop in nerve conduction velocity. Sensory neurones were ATF-3 positive and animals exhibited joint pain and knee joint damage. MIA-treated rats also showed signs of demyelination and joint neuropathy with concomitant pain. Nerve damage and pain could be ameliorated by Ki-16425 pre-treatment. CONCLUSION: Intra-articular injection of LPA caused knee joint neuropathy, joint damage and pain. Pharmacological blockade of LPA receptors inhibited joint nerve damage and hindlimb incapacitance. Thus, LPA is a candidate molecule for the development of OA nerve damage and the origin of joint neuropathic pain.

Identification and pharmacological characterization of a novel inhibitor of autotaxin in rodent models of joint pain.

OBJECTIVE: Autotaxin is a secreted lysophospholipase that mediates the conversion of lysophosphatidyl choline (LPC) to lysophosphatidic acid (LPA), a bioactive lipid mediator. Autotaxin levels in plasma and synovial fluid correlate with disease severity in patients with knee osteoarthritis (OA). The goal of this study was to develop and characterize a novel small molecule inhibitor of autotaxin to inhibit LPA production in vivo and determine its efficacy in animal models of musculoskeletal pain. DESIGN: Compound libraries were screened using an LPC coupled enzyme assay that measures the amount of choline released from LPC by the action of autotaxin. Hits from this assay were tested in a plasma assay to assess inhibition of endogenous plasma autotaxin and subsequently tested for their ability to lower plasma LPA levels upon oral dosing of rats. The best compounds were then tested in animal models of musculoskeletal pain. RESULTS: Compound screening led to the identification of compounds with nanomolar potency for inhibition of autotaxin activity. Studies in rats demonstrated a good correlation between compound exposure levels and a decrease in LPA levels in plasma. The leading molecule (compound-1) resulted in a dose dependent decrease in joint pain in the mono-sodium iodoacetate (MIA) and meniscal tear models and a decrease in bone fracture pain in the osteotomy model in rats. CONCLUSION: We have identified and characterized a novel small molecule inhibitor of autotaxin and demonstrated its efficacy in animal models of musculoskeletal pain. The inhibitor has the potential to serve as an analgesic for human OA and bone fracture.