CHD1 loss sensitizes prostate cancer to DNA damaging therapy by promoting error-prone double-strand break repair.

BACKGROUND: Deletion of the chromatin remodeler chromodomain helicase DNA-binding protein 1 (CHD1) is a common genomic alteration found in human prostate cancers (PCas). CHD1 loss represents a distinct PCa subtype characterized by SPOP mutation and higher genomic instability. However, the role of CHD1 in PCa development in vivo and its clinical utility remain unclear. PATIENTS AND METHODS: To study the role of CHD1 in PCa development and its loss in clinical management, we generated a genetically engineered mouse model with prostate-specific deletion of murine Chd1 as well as isogenic CHD1 wild-type and homozygous deleted human benign and PCa lines. We also developed patient-derived organoid cultures and screened patients with metastatic PCa for CHD1 loss. RESULTS: We demonstrate that CHD1 loss sensitizes cells to DNA damage and causes a synthetic lethal response to DNA damaging therapy in vitro, in vivo, ex vivo, in patient-derived organoid cultures and in a patient with metastatic PCa. Mechanistically, CHD1 regulates 53BP1 stability and CHD1 loss leads to decreased error-free homologous recombination (HR) repair, which is compensated by increased error-prone non-homologous end joining (NHEJ) repair for DNA double-strand break (DSB) repair. CONCLUSIONS: Our study provides the first in vivo and in patient evidence supporting the role of CHD1 in DSB repair and in response to DNA damaging therapy. We uncover mechanistic insights that CHD1 modulates the choice between HR and NHEJ DSB repair and suggest that CHD1 loss may contribute to the genomic instability seen in this subset of PCas.

Evidence that small molecule enhancement of ß-hexosaminidase activity corrects the behavioral phenotype in Dutch APP(E693Q) mice through reduction of ganglioside-bound Aß.

Certain mutant Alzheimer's amyloid-ß (Aß) peptides (that is, Dutch mutant APP(E693Q)) form complexes with gangliosides (GAß). These mutant Aß peptides may also undergo accelerated aggregation and accumulation upon exposure to GM2 and GM3. We hypothesized that increasing ß-hexosaminidase (ß-hex) activity would lead to a reduction in GM2 levels, which in turn, would cause a reduction in Aß aggregation and accumulation. The small molecule OT1001 is a ß-hex-targeted pharmacological chaperone with good bioavailability, blood-brain barrier penetration, high selectivity for ß-hex and low cytotoxicity. Dutch APP(E693Q) transgenic mice accumulate oligomeric Aß as they age, as well as Aß oligomer-dose-dependent anxiety and impaired novel object recognition (NOR). Treatment of Dutch APP(E693Q) mice with OT1001 caused a dose-dependent increase in brain ß-hex levels up to threefold over those observed at baseline. OT1001 treatment was associated with reduced anxiety, improved learning behavior in the NOR task and dramatically reduced GAß accumulation in the subiculum and perirhinal cortex, both of which are brain regions required for normal NOR. Pharmacological chaperones that increase ß-hex activity may be useful in reducing accumulation of certain mutant species of Aß and in preventing the associated behavioral pathology.

Immunomodulation and AD--down but not out.

Alzheimer's disease (AD) is a progressive neurodegenerative disorder and is the most common cause of dementia in the elderly. Interventions that remove existing fibrillar and oligomeric amyloid-ß (Aß) are believed to be essential for the success of any attempt at stabilization of brain function and mitigation of cognitive decline. Many of these strategies have focused on Aß vaccination and administration of anti-Aß antibodies. Both active and passive immunotherapies have been successful in mouse models, but both have had limited effect in clinical trials. Intravenous immunoglobulin (IVIG) has been proposed as a potential treatment for AD following evidence for behavioral benefit in AD models and cognitive benefit in early phase 1 and phase 2 clinical trials. A phase 3 trial IVIG trial failed to meet its primary outcomes. While there was a statistically significant benefit in moderate stage AD patients who carried an APOE ε4 allele, this stabilization of cognition was evident only on neuropsychological examination. No benefit on activities of daily living was evident, therefore failing to qualify AD as a new indication for IVIG. Identifying the biologically active component (s) responsible for the neuropsychological benefit in APOE ε4-positive AD patients could enable the development of a compound with greater potency that would qualify for FDA (US Food and Drug Administration) registration.

Development of a liquid-helium free cryogenic sample holder with mK temperature control for autonomous electron microscopy.

The automated and autonomous cryogenic transmission electron microscopy (Cryo-EM) demands a sample holder capable of maintaining temperatures below 10 K with precise control, long holding times, and minimal helium use. Rising to this challenge, we initiated an ambitious project to develop a novel closed-cycle cryocooler-based cryogenic sample holder that operates without the use of liquid helium and the consumption of gaseous helium. This article presents the design, construction, and experimental testing of the initial prototype, which achieves an ultimate temperature of 5.6 K with exceptional stability close to 1mK, while providing a wide temperature control range from 295 K to 5.6 K, marking a clear advancement in cryo-EM holder development. While the prototype was not designed for atomic resolution imaging and thus lacks a sturdy support system to mitigate mechanical vibrations from the cryocooler's pulsed tube, this innovative approach successfully demonstrates proof of concept. It offers unprecedented capabilities for state-of-the-art cryogenic microscopy and microanalysis in materials and biological sciences.

The Implementation of Chimeric Antigen Receptor (CAR) T-cell Therapy in Pediatric Patients: Where Did We Come From, Where Are We Now, and Where are We Going?

CD19-directed Chimeric Antigen Receptor (CAR) T-cell therapy has revolutionized the treatment of patients with B-cell acute lymphoblastic leukemia (B-ALL). Somewhat uniquely among oncologic clinical trials, early clinical development occurred simultaneously in both children and adults. In subsequent years however, the larger number of adult patients with relapsed/refractory (r/r) malignancies has led to accelerated development of multiple CAR T-cell products that target a variety of malignancies, resulting in six currently FDA-approved for adult patients. By comparison, only a single CAR-T cell therapy is approved by the FDA for pediatric patients: tisagenlecleucel, which is approved for patients ≤ 25 years with refractory B-cell precursor ALL, or B-cell ALL in second or later relapse. Tisagenlecleucel is also under evaluation in pediatric patients with relapsed/refractory B-cell non-Hodgkin lymphoma, but is not yet been approved for this indication. All the other FDA-approved CD19-directed CAR-T cell therapies available for adult patients (axicabtagene ciloleucel, brexucabtagene autoleucel, and lisocabtagene maraleucel) are currently under investigations among children, with preliminary results available in some cases. As the volume and complexity of data continue to grow, so too does the necessity of rapid assimilation and implementation of those data. This is particularly true when considering "atypical" situations, e.g. those arising when patients do not precisely conform to the profile of those included in pivotal clinical trials, or when alternative treatment options (e.g. hematopoietic stem cell transplantation (HSCT) or bispecific T-cell engagers (BITEs)) are also available. We have therefore developed a relevant summary of the currently available literature pertaining to the use of CD19-directed CAR-T cell therapies in pediatric patients, and sought to provide guidance for clinicians seeking additional data about specific clinical situations.

External workload and cognitive performance of a tactical military scenario-based field exercise.

INTRODUCTION: Military personnel must manage a multitude of competing physiological and cognitive stressors while maintaining high levels of performance. Quantifying the external workload and cognitive demands of tactical military field exercises closely simulating operational environments, will provide a better understanding of stressors placed on personnel to inform evidence-based interventions. METHODS: Thirty-one soldiers completing a dismounted 48 hours tactical field exercise, participated in the study. External workload was quantified using a wrist-worn triaxial accelerometer, with cognitive function (Go-/No-Go, N-back, psychomotor vigilance task and subjective workload ratings (NASA-TLX) assessed pre-exercise, mid-exercise and postexercise. Physical activity was described using Euclidian Norm Minus One (mg), with moderate vigorous physical activity (MVPA) and sedentary light physical activity (SLPA) as ≥ or <113 mg, respectively. Changes in general cognitive performance (total accuracy-speed trade-off (ASTO) % change) and function outcome variables (overall mean reaction time, ASTO and number of correct and missed responses) were calculated for each assessment from pre-exercise, to mid-exercise and postexercise. RESULTS: For the exercise duration (50:12±02:06 hh:mm) participants spent more time completing SLPA compared with MVPA (1932±234 vs 1074±194 min; p<0.001), equating to 33% of the time spent completing MVPA. Overall cognitive performance decreased over the exercise (pre-to-post: -249). However, the largest decrement was observed pre-to-mid (-168). Perceived mental demand associated with the cognitive assessments significantly increased over the duration of the exercise (pre-: 33; mid-: 38 and post-: 51; χ2 F(2) = 26.7, p = <0.001, W=0.477) which could suggest that participants were able to attenuate a further decline in cognitive performance by investing more effort/mental resources when completing assessments. CONCLUSION: The study successfully quantified the physical activity, and subsequent impact on cognitive function, in soldiers completing a 48 hours tactical field exercise. Further research is needed to better understand how physiological stressors interact with cognitive function during military operations.

Effects of ganaxolone on non-seizure outcomes in CDKL5 Deficiency Disorder: Double-blind placebo-controlled randomized trial.

CDKL5 deficiency disorder (CDD) is a rare developmental and epileptic encephalopathy. Ganaxolone, a neuroactive steroid, reduces the frequency of major motor seizures in children with CDD. This analysis explored the effect of ganaxolone on non-seizure outcomes. Children (2-19 years) with genetically confirmed CDD and ≥ 16 major motor seizures per month were enrolled in a double-blind randomized placebo-controlled trial. Ganaxolone or placebo was administered three times daily for 17 weeks. Behaviour was measured with the Anxiety, Depression and Mood Scale (ADAMS), daytime sleepiness with the Child Health Sleep Questionnaire, and quality of life with the Quality of Life Inventory-Disability (QI-Disability) scale. Scores were compared using ANOVA, adjusted for age, sex, number of anti-seizure mediations, baseline 28-day major motor seizure frequency, baseline developmental skills, and behaviour, sleep or quality of life scores. 101 children with CDD (39 clinical sites, 8 countries) were randomized. Median (IQR) age was 6 (3-10) years, 79.2 % were female, and 50 received ganaxolone. After 17 weeks of treatment, Manic/Hyperactive scores (mean difference 1.27, 95%CI -2.38,-0.16) and Compulsive Behaviour scores (mean difference 0.58, 95%CI -1.14,-0.01) were lower (improved) in the ganaxolone group compared with the placebo group. Daytime sleepiness scores were similar between groups. The total change in QOL score for children in the ganaxolone group was 2.6 points (95%CI -1.74,7.02) higher (improved) than in the placebo group but without statistical significance. Along with better seizure control, children who received ganaxolone had improved behavioural scores in select domains compared to placebo.

Adapting a measure of gross motor skills for individuals with CDKL5 deficiency disorder: A psychometric study.

PURPOSE: Validated measures capable of demonstrating meaningful interventional change in the CDKL5 deficiency disorder (CDD) are lacking. The study objective was to modify the Rett Syndrome Gross Motor Scale (RSGMS) and evaluate its psychometric properties for individuals with CDD. METHODS: Item and scoring categories of the RSGMS were modified. Caregivers registered with the International CDKL5 Clinical Research Network uploaded motor videos filmed at home to a protected server and completed a feedback questionnaire (n = 70). Rasch (n = 137), known groups (n = 109), and intra- and inter-rater reliability analyses (n = 50) were conducted. RESULTS: The age of individuals with CDD ranged from 1.5 to 34.1 years. The modified scale, Gross Motor-Complex Disability (GM-CD), comprised 17 items. There were no floor or ceiling effects and inter- and intra-rater reliability were good. Rasch analysis demonstrated that the items encompassed a large range of performance difficulty, although there was some item redundancy and some disordered categories. One item, Prone Head Position, was a poor fit. Caregiver-reported acceptability was positive. Scores differed by age and functional abilities. SUMMARY: GM-CD appears to be a suitable remotely administered measure and psychometrically sound for individuals with CDD. This study provides the foundation to propose the use of GM-CD in CDD clinical trials. Longitudinal evaluation is planned.

Prenatal iodine supplementation and early childhood neurodevelopment: the PoppiE trial - study protocol for a multicentre randomised controlled trial.

INTRODUCTION: Observational studies suggest both low and high iodine intakes in pregnancy are associated with poorer neurodevelopmental outcomes in children. This raises concern that current universal iodine supplement recommendations for pregnant women in populations considered to be iodine sufficient may negatively impact child neurodevelopment. We aim to determine the effect of reducing iodine intake from supplements for women who have adequate iodine intake from food on the cognitive development of children at 24 months of age. METHODS AND ANALYSIS: A multicentre, randomised, controlled, clinician, researcher and participant blinded trial with two parallel groups. Using a hybrid decentralised clinical trial model, 754 women (377 per group) less than 13 weeks' gestation with an iodine intake of ≥165 µg/day from food will be randomised to receive either a low iodine (20 µg/day) multivitamin and mineral supplement or an identical supplement containing 200) µg/day (amount commonly used in prenatal supplements in Australia), from enrolment until delivery. The primary outcome is the developmental quotient of infants at 24 months of age assessed with the Cognitive Scale of the Bayley Scales of Infant Development, fourth edition. Secondary outcomes include infant language and motor development; behavioural and emotional development; maternal and infant clinical outcomes and health service utilisation of children. Cognitive scores will be compared between groups using linear regression, with adjustment for location of enrolment and the treatment effect described as a mean difference with 95% CI. ETHICS AND DISSEMINATION: Ethical approval has been granted from the Women's and Children's Health Network Research Ethics Committee (HREC/17/WCHN/187). The results of this trial will be presented at scientific conferences and published in peer-reviewed journals. TRIAL REGISTRATION NUMBER: NCT04586348.

Rapid assessment of hand reaching using virtual reality and application in cerebellar stroke.

The acquisition of sensory information about the world is a dynamic and interactive experience, yet the majority of sensory research focuses on perception without action and is conducted with participants who are passive observers with very limited control over their environment. This approach allows for highly controlled, repeatable experiments and has led to major advances in our understanding of basic sensory processing. Typical human perceptual experiences, however, are far more complex than conventional action-perception experiments and often involve bi-directional interactions between perception and action. Innovations in virtual reality (VR) technology offer an approach to close this notable disconnect between perceptual experiences and experiments. VR experiments can be conducted with a high level of empirical control while also allowing for movement and agency as well as controlled naturalistic environments. New VR technology also permits tracking of fine hand movements, allowing for seamless empirical integration of perception and action. Here, we used VR to assess how multisensory information and cognitive demands affect hand movements while reaching for virtual targets. First, we manipulated the visibility of the reaching hand to uncouple vision and proprioception in a task measuring accuracy while reaching toward a virtual target (n = 20, healthy young adults). The results, which as expected revealed multisensory facilitation, provided a rapid and a highly sensitive measure of isolated proprioceptive accuracy. In the second experiment, we presented the virtual target only briefly and showed that VR can be used as an efficient and robust measurement of spatial memory (n = 18, healthy young adults). Finally, to assess the feasibility of using VR to study perception and action in populations with physical disabilities, we showed that the results from the visual-proprioceptive task generalize to two patients with recent cerebellar stroke. Overall, we show that VR coupled with hand-tracking offers an efficient and adaptable way to study human perception and action.

Impact of gavage dosing procedure and gastric content on adverse respiratory effects and mortality in rat toxicity studies.

Unscheduled mortality preceded by adverse respiratory clinical signs in rats dosed by oral gavage may not only be caused by technical gavage error or systemic toxicity but may also be caused by gastro-esophageal reflux and subsequent aspiration of high concentrations of drug formulation. In a 3 week oral gavage rat toxicity study for an early drug development compound, preterminal deaths (approximately 20% of animals) at high doses (≥1000 mg kg(-1) ) and concentrations (≥60 mg ml(-1) ) were preceded by recurrent dyspnea, rales or excessive salivation, without evidence of accidental intrapulmonary gavage error. Histological evaluation revealed extensive necrosis and inflammatory changes in the upper respiratory tract, especially in the nasal turbinates and/or nasopharynx. The presence of food particles in inflammatory exudates suggested a retrograde aspiration of stomach content with test formulation via the nasopharyngeal duct into the posterior region of the nose. In contrast, no mortality or adverse respiratory effects were observed in rats following 2 week intravenous administration at comparable exposures or oral gavage administration at lower concentrations (≤20 mg ml(-1) ). In a pharmacology study, the compound caused a dose-dependent increase in gastric content (partly due to inhibition of gastric emptying), providing a pharmacological basis for the suspected gavage-mediated gastroesophageal reflux. Reducing the dose volume and dosing fasted animals substantially reduced or eliminated the respiratory effects and mortality at the high test article concentrations, demonstrating that the adverse effects are related to the gavage method.

Using Advanced Cell Culture Techniques to Differentiate Pluripotent Stem Cells and Recreate Tissue Structures Representative of Teratoma Xenografts.

Various methods are currently used to investigate human tissue differentiation, including human embryo culture and studies utilising pluripotent stem cells (PSCs) such as in vitro embryoid body formation and in vivo teratoma assays. Each method has its own distinct advantages, yet many are limited due to being unable to achieve the complexity and maturity of tissue structures observed in the developed human. The teratoma xenograft assay allows maturation of more complex tissue derivatives, but this method has ethical issues surrounding animal usage and significant protocol variation. In this study, we have combined three-dimensional (3D) in vitro cell technologies including the common technique of embryoid body (EB) formation with a novel porous scaffold membrane, in order to prolong cell viability and extend the differentiation of PSC derived EBs. This approach enables the formation of more complex morphologically identifiable 3D tissue structures representative of all three primary germ layers. Preliminary in vitro work with the human embryonal carcinoma line TERA2.SP12 demonstrated improved EB viability and enhanced tissue structure formation, comparable to teratocarcinoma xenografts derived in vivo from the same cell line. This is thought to be due to reduced diffusion distances as the shape of the spherical EB transforms and flattens, allowing for improved nutritional/oxygen support to the developing structures over extended periods. Further work with EBs derived from murine embryonic stem cells demonstrated that the formation of a wide range of complex, recognisable tissue structures could be achieved within 2-3 weeks of culture. Rudimentary tissue structures from all three germ layers were present, including epidermal, cartilage and epithelial tissues, again, strongly resembling tissue structure of teratoma xenografts of the same cell line. Proof of concept work with EBs derived from the human embryonic stem cell line H9 also showed the ability to form complex tissue structures within this system. This novel yet simple model offers a controllable, reproducible method to achieve complex tissue formation in vitro. It has the potential to be used to study human developmental processes, as well as offering an animal free alternative method to the teratoma assay to assess the developmental potential of novel stem cell lines.

Turnover of HeLa ribosomal RNA. The characterization of a class of RNA in HeLa cytoplasm derived from 28S RNA.

A class of RNA in HeLa cytoplasm with a sedimentation value of 22S is described. This RNA is a true cytoplasmic component and is not an artifact of cell rupture or of the method of RNA preparation. The 22S RNA sediments in a sucrose gradient with those ribosomal structures containing 28S ribosomal RNA (60S and 74S particles and polyribosomes). It has a base composition and methyl content similar to those of 28S RNA. The kinetics of formation of 22S suggest that it is not a direct product of transcription but is derived in vivo from "old" molecules of 28S RNA.

Human fibroblast interferon: amino acid analysis and amino terminal amino acid sequence.

The purification of human fibroblast interferon has been simplified to a two-step procedure consisting of affinity chromatography on Blue Sepharose and sodium dodecyl sulfate polyacrlamide gel electrophoresis. A preliminary amino acid composition and the sequence of the 13 amino-terminal residues of homogeneous interferon prepared by this method is reported.

Fitbit Activity Trackers Interrupt Workplace Sedentary Behavior: A New Application.

This study investigated whether Fitbit devices can reduce sedentary behavior among employees in the workplace. Participants were asked to wear Fitbits during 8-hour work shifts, 5 days per week, for 8 weeks. They were instructed to stand at least once every 30 minutes throughout the workday. The goal of the study was to determine whether standing once every 30 minutes was a feasible strategy for reducing sedentary workplace behavior. On average, participants completed 36 of 40 workdays using Fitbits. The number of times participants stood during an 8-hour workday averaged 12 stands per day (maximum 16 stands per day). These results indicate that Fitbit technology is effective for recording and tracking interruptions in sitting time; however, to reduce sitting behavior, alternate approaches are required to motivate larger numbers of workers to participate.

Ventilator-dependent survivors of catastrophic illness transferred to 23 long-term care hospitals for weaning from prolonged mechanical ventilation.

STUDY OBJECTIVES: This multicenter study was undertaken to characterize the population of ventilator-dependent patients admitted to long-term care hospitals (LTCHs) for weaning from mechanical ventilation. DESIGN: Observational study with concurrent data collection. Characteristics of the LTCHs were also surveyed. SETTING: Twenty-three LTCHs in the United States. PATIENTS: Consecutive ventilator-dependent patients admitted over a 1-year period: March 1, 2002, to February 28, 2003. RESULTS: A total of 1,419 patients were enrolled in the Ventilation Outcomes Study. Median age of the patients was 71.8 years old (range, 18 to 97.7 years), with an equal gender distribution. The premorbid domicile was home or assisted living in 86.5%; "good" premorbid functional status (Zubrod score 0-2) was assessed in 77%. There was a history of smoking in 59% (mean, 57 +/- 42 pack-years [+/- SD]); premorbid diagnoses averaged 2.6 per patient. Patients came to the LTCH after mean of 33.8 +/- 29 days at the transferring hospital; mean time to tracheotomy was 15.0 +/- 10 days. A medical illness led to ventilator dependency in 60.8% of patients; a surgical procedure led to ventilatory dependency in 39.2%. On admission to the LTCH, the median acute physiology score of APACHE (acute physiology and chronic health evaluation) III was 35 (range, 4 to 115); > 90% of patients had at least three penetrating indwelling tubes/catheters; 42% of patients had stage 2 or higher pressure ulceration. CONCLUSIONS: This is the first multicenter study to characterize ventilator-dependent survivors of catastrophic illness admitted to the post-ICU venue of LTCHs for weaning from prolonged mechanical ventilation (PMV). Overall, our findings suggest that ventilator-dependent patients admitted to LTCHs for weaning will continue to require considerable medical interventions and treatments, owing to the burden of acute-on-chronic diseases resulting in PMV.

Post-ICU mechanical ventilation at 23 long-term care hospitals: a multicenter outcomes study.

STUDY OBJECTIVES: This multicenter study was undertaken to characterize the population of ventilator-dependent patients admitted to long-term care hospitals (LTCHs) with weaning programs, and to report treatments, complications, weaning outcome, discharge disposition, and survival in these patients. DESIGN: Observational study with concurrent data collection. SETTING: Twenty-three LTCHs in the United States. PATIENTS: Consecutive ventilator-dependent patients admitted over a 1-year period: March 1, 2002, to February 28, 2003. RESULTS: A total of 1,419 patients were enrolled in the Ventilation Outcomes Study. Median age of patients was 71.8 years (range, 18 to 97.7 years). Patients averaged 6.9 procedures and treatments during the LTCH hospitalization; median length of stay was 40 days (range, 1 to 365 days). Seven of the 10 most frequent complications treated at the LTCH were infections; congestive heart failure and diabetes mellitus were the most common comorbidities requiring treatment. Outcomes of weaning attempts, scored at LTCH discharge, were 54.1% weaned, 20.9% ventilator dependent, and 25.0% deceased. Median time to wean (n = 766) was 15 days (range, 7 to 30 days). Discharge disposition included 28.8% to home, 49.2% to rehabilitation and extended-care facilities, and 19.5% to short-stay acute hospitals. Nearly one third of patients were known to be alive 12 months after admission to the LTCH. CONCLUSIONS: Patients admitted to LTCHs for weaning attempts were elderly, with acute-on-chronic diseases, and continued to require considerable medical interventions and treatments. The frequency and type of complications were not surprising following prolonged and aggressive ICU interventions. In the continuum of critical care medicine, more than half of ventilator-dependent survivors of catastrophic illness transferred from the ICU were successfully weaned from prolonged mechanical ventilation in the setting of an LTCH.

Oral anticoagulation in atrial fibrillation: A pan-European patient survey.

BACKGROUND: Anticoagulation with vitamin K antagonists (VKAs) provides effective stroke prophylaxis in patients with atrial fibrillation (AF). Optimisation of such therapy requires frequent monitoring, dose adjustments and stringent lifestyle restrictions. We conducted a large multinational survey in patients with chronic AF to gain insights into their perceptions and understanding of VKA use. METHODS: Eligible patients were adults with AF who had been prescribed VKAs for at least 1 year. A total of 711 patient interviews were conducted in seven European countries during June and July 2004. RESULTS: The majority of patients (58% male; mean age 68 years) claimed to understand their treatment programme; despite this, only 7% knew that VKA use is aimed at preventing strokes and 24% stated that they would have liked more information. Patients attended an average of 14 monitoring sessions in the previous year; however, 21% missed appointments, especially younger patients (<65 years). The International Normalized Ratio (INR) was within the target range in most or all of the last five to ten visits in 64% of patients; nonetheless, 38% were not aware that an INR outside the target range is associated with health risks. On average, patients required dose adjustments every four sessions. VKA treatment impacted 67% of patients in terms of diet, socialising, career and independence, especially younger patients (74%). CONCLUSIONS: Monitoring, dose adjustments and lifestyle restrictions to optimise the intensity of anticoagulation with VKAs are problematic for patients with AF, and their knowledge of the consequences of such therapy is often poor.

Prospective controlled cohort study of Troponin I levels in patients undergoing elective spine surgery for degenerative conditions: Prone versus supine position.

Prior studies have suggested that elevated serum Troponin-I (TnI) levels immediately after non-cardiac surgical procedures (8-40%) represent subclinical cardiac stress which independently predicts increased 30-day mortality. Routine post-operative TnI monitoring has therefore been suggested as a standard of care. However, no prior studies have focussed on elective degenerative spine surgery, whilst few have measured pre-op TnI. Further, prolonged prone positioning could represent an additional, independent, cardiac stress. We planned a prospective controlled cohort study of consecutive TnI levels in routine elective spine surgery for degenerative spine conditions, incorporating 3 groups: 'prone<2h', 'prone>2h' and 'supine' positioning. TnI levels (>0.04µg/L) were recorded immediately pre-/post-surgery, and by 24h of surgery. N=120 patients were recruited. Complete results were obtained in 92 (39 supine, 53 prone). No significant between-groups differences were observed in demographic or cardiovascular risk factors. Validated TnI-elevation by 24h was not observed in any group. Spurious elevations were recorded in one 'prone<2h' and one 'prone>2h'. One non-ST segment myocardial infarction (STEMI) occurred on day 7 without TnI elevation by 24h (prone>2h). There was no 30-day mortality. CONCLUSIONS: Despite a lower cut-off, no validated TnI elevation was observed in any group by 24h after surgery. One non-STEMI had not been associated with TnI-elevation by 24h. Immediately peri-operative cardiac stress therefore appeared comparatively rare in patients undergoing routine elective spine surgery. Further, prone positioning did not represent an additional, independent, risk. Routine immediately post-operative TnI monitoring in elective spine surgery therefore appears unjustified. Our study highlighted several caveats regarding consecutive TnI testing.

Marker-based quantitative genetics in the wild?: the heritability and genetic correlation of chemical defenses in eucalyptus.

Marker-based methods for estimating heritability and genetic correlation in the wild have attracted interest because traditional methods may be impractical or introduce bias via G x E effects, mating system variation, and sampling effects. However, they have not been widely used, especially in plants. A regression-based approach, which uses a continuous measure of genetic relatedness, promises to be particularly appropriate for use in plants with mixed-mating systems and overlapping generations. Using this method, we found significant narrow-sense heritability of foliar defense chemicals in a natural population of Eucalyptus melliodora. We also demonstrated a genetic basis for the phenotypic correlation underlying an ecological example of conditioned flavor aversion involving different biosynthetic pathways. Our results revealed that heritability estimates depend on the spatial scale of the analysis in a way that offers insight into the distribution of genetic and environmental variance. This study is the first to successfully use a marker-based method to measure quantitative genetic parameters in a tree. We suggest that this method will prove to be a useful tool in other studies and offer some recommendations for future applications of the method.