Arabidopsis AN3 and OLIGOCELLULA genes link telomere maintenance mechanisms with cell division and expansion control.

Telomeres are conserved chromosomal structures necessary for continued cell division and proliferation. In addition to the classical telomerase pathway, multiple other genes including those involved in ribosome metabolism and chromatin modification contribute to telomere length maintenance. We previously reported that Arabidopsis thaliana ribosome biogenesis genes OLI2/NOP2A, OLI5/RPL5A and OLI7/RPL5B have critical roles in telomere length regulation. These three OLIGOCELLULA genes were also shown to function in cell proliferation and expansion control and to genetically interact with the transcriptional co-activator ANGUSTIFOLIA3 (AN3). Here we show that AN3-deficient plants progressively lose telomeric DNA in early homozygous mutant generations, but ultimately establish a new shorter telomere length setpoint by the fifth mutant generation with a telomere length similar to oli2/nop2a -deficient plants. Analysis of double an3 oli2 mutants indicates that the two genes are epistatic for telomere length control. Telomere shortening in an3 and oli mutants is not caused by telomerase inhibition; wild type levels of telomerase activity are detected in all analyzed mutants in vitro. Late generations of an3 and oli mutants are prone to stem cell damage in the root apical meristem, implying that genes regulating telomere length may have conserved functional roles in stem cell maintenance mechanisms. Multiple instances of anaphase fusions in late generations of oli5 and oli7 mutants were observed, highlighting an unexpected effect of ribosome biogenesis factors on chromosome integrity. Overall, our data implicate AN3 transcription coactivator and OLIGOCELLULA proteins in the establishment of telomere length set point in plants and further suggest that multiple regulators with pleiotropic functions can connect telomere biology with cell proliferation and cell expansion pathways.

Arabidopsis AN3 and OLIGOCELLULA genes link telomere maintenance mechanisms with cell division and expansion control.

Telomeres are conserved chromosomal structures necessary for continued cell division and proliferation. In addition to the classical telomerase pathway, multiple other genes including those involved in ribosome metabolism and chromatin modification contribute to telomere length maintenance. We previously reported that Arabidopsis thaliana ribosome biogenesis genes OLI2/NOP2A, OLI5/RPL5A and OLI7/RPL5B have critical roles in telomere length regulation. These three OLIGOCELLULA genes were also shown to function in cell proliferation and expansion control and to genetically interact with the transcriptional co-activator ANGUSTIFOLIA3 (AN3). Here we show that AN3-deficient plants progressively lose telomeric DNA in early homozygous mutant generations, but ultimately establish a new shorter telomere length setpoint by the fifth mutant generation with a telomere length similar to oli2/nop2a - deficient plants. Analysis of double an3 oli2 mutants indicates that the two genes are epistatic for telomere length control. Telomere shortening in an3 and oli mutants is not caused by telomerase inhibition; wild type levels of telomerase activity are detected in all analyzed mutants in vitro. Late generations of an3 and oli mutants are prone to stem cell damage in the root apical meristem, implying that genes regulating telomere length may have conserved functional roles in stem cell maintenance mechanisms. Multiple instances of anaphase fusions in late generations of oli5 and oli7 mutants were observed, highlighting an unexpected effect of ribosome biogenesis factors on chromosome integrity. Overall, our data implicate AN3 transcription coactivator and OLIGOCELLULA proteins in the establishment of telomere length set point in plants and further suggest that multiple regulators with pleiotropic functions can connect telomere biology with cell proliferation and cell expansion pathways.

Treatment of rheumatoid arthritis-associated interstitial lung disease in a multi-center registry cohort.

Background: Rheumatoid arthritis-associated interstitial lung disease (RA-ILD) is challenging to manage, with a paucity of robust data to guide treatment. Our aim was to characterize the pharmacologic treatment of RA-ILD utilizing a retrospective design in a national multi-center prospective cohort, and to identify associations between treatment and change in lung function and survival. Methods: Patients with RA-ILD and a radiological pattern of non-specific interstitial pneumonia (NSIP) or usual interstitial pneumonia (UIP) were included. Unadjusted and adjusted linear mixed models and Cox proportional hazards models were used to compare lung function change and risk of death or lung transplant by radiologic patterns and treatment. Results: Of 161 patients with RA-ILD, UIP pattern was more common than NSIP (55.9% vs. 44.1%). Only 44/161 (27%) patients were treated over median follow-up of 4 years with medication choice appearing unrelated to patient-specific variables. Decline in forced vital capacity (FVC) was not associated with treatment. Patients with NSIP had lower risk of death or transplant, compared to UIP (P=0.0042). In patients with NSIP, there was no difference in time to death or transplant comparing treated to untreated in adjusted models [hazard ratio (HR) =0.73; 95% confidence interval (CI): 0.15-3.62; P=0.70]. Similarly, in patients with UIP, there was no difference in time to death or lung transplant between treated and untreated in adjusted models (HR =1.06; 95% CI: 0.49-2.28; P=0.89). Conclusions: Treatment of RA-ILD is heterogeneous, with most patients in this cohort not receiving treatment. Patients with UIP had worse outcomes compared to NSIP, similar to other cohorts. Randomized clinical trials are needed to inform pharmacologic therapy in this patient population.

Quantification of 8-oxoG in Plant Telomeres.

Chemical modifications in DNA impact gene regulation and chromatin structure. DNA oxidation, for example, alters gene expression, DNA synthesis and cell cycle progression. Modification of telomeric DNA by oxidation is emerging as a marker of genotoxic damage and is associated with reduced genome integrity and changes in telomere length and telomerase activity. 8-oxoguanine (8-oxoG) is the most studied and common outcome of oxidative damage in DNA. The G-rich nature of telomeric DNA is proposed to make it a hotspot for oxidation, but because telomeres make up only a tiny fraction of the genome, it has been difficult to directly test this hypothesis by studying dynamic DNA modifications specific to this region in vivo. Here, we present a new, robust method to differentially enrich telomeric DNA in solution, coupled with downstream methods for determination of chemical modification. Specifically, we measure 8-oxoG in Arabidopsis thaliana telomeres under normal and oxidative stress conditions. We show that telomere length is unchanged in response to oxidative stress in three different wild-type accessions. Furthermore, we report that while telomeric DNA comprises only 0.02-0.07% of the total genome, telomeres contribute between 0.2 and 15% of the total 8-oxoG. That is, plant telomeres accumulate 8-oxoG at levels approximately 100-fold higher than the rest of the genome under standard growth conditions. Moreover, they are the primary targets of further damage upon oxidative stress. Interestingly, the accumulation of 8-oxoG in the chromosome body seems to be inversely proportional to telomere length. These findings support the hypothesis that telomeres are hotspots of 8-oxoG and may function as sentinels of oxidative stress in plants.

Prevalence and characteristics of progressive fibrosing interstitial lung disease in a prospective registry.

BACKGROUND: Progressive fibrosing interstitial lung disease (PF-ILD) is characterised by progressive physiological, symptomatic and/or radiographic worsening. The real-world prevalence and characteristics of PF-ILD remain uncertain. METHODS: Patients were enrolled from the Canadian Registry for Pulmonary Fibrosis between 2015 and 2020. PF-ILD was defined as a relative forced vital capacity (FVC) decline ≥10%, death, lung transplantation or any two of: relative FVC decline ≥5% and <10%, worsening respiratory symptoms or worsening fibrosis on computed tomography of the chest, all within 24 months of diagnosis. Time-to-event analysis compared progression between key diagnostic subgroups. Characteristics associated with progression were determined by multivariable regression. RESULTS: Of 2746 patients with fibrotic ILD (mean±sd age 65±12 years; 51% female), 1376 (50%) met PF-ILD criteria in the first 24 months of follow-up. PF-ILD occurred in 427 (59%) patients with idiopathic pulmonary fibrosis (IPF), 125 (58%) with fibrotic hypersensitivity pneumonitis (HP), 281 (51%) with unclassifiable ILD (U-ILD) and 402 (45%) with connective tissue disease-associated ILD (CTD-ILD). Compared with IPF, time to progression was similar in patients with HP (hazard ratio (HR) 0.96, 95% CI 0.79-1.17), but was delayed in patients with U-ILD (HR 0.82, 95% CI 0.71-0.96) and CTD-ILD (HR 0.65, 95% CI 0.56-0.74). Background treatment varied across diagnostic subtypes, with 66% of IPF patients receiving antifibrotic therapy, while immunomodulatory therapy was utilised in 49%, 61% and 37% of patients with CHP, CTD-ILD and U-ILD, respectively. Increasing age, male sex, gastro-oesophageal reflux disease and lower baseline pulmonary function were independently associated with progression. CONCLUSIONS: Progression is common in patients with fibrotic ILD, and is similarly prevalent in HP and IPF. Routinely collected variables help identify patients at risk for progression and may guide therapeutic strategies.

Natural variation in plant telomere length is associated with flowering time.

Telomeres are highly repetitive DNA sequences found at the ends of chromosomes that protect the chromosomes from deterioration duringcell division. Here, using whole-genome re-sequencing and terminal restriction fragment assays, we found substantial natural intraspecific variation in telomere length in Arabidopsis thaliana, rice (Oryza sativa), and maize (Zea mays). Genome-wide association study (GWAS) mapping in A. thaliana identified 13 regions with GWAS-significant associations underlying telomere length variation, including a region that harbors the telomerase reverse transcriptase (TERT) gene. Population genomic analysis provided evidence for a selective sweep at the TERT region associated with longer telomeres. We found that telomere length is negatively correlated with flowering time variation not only in A. thaliana, but also in maize and rice, indicating a link between life-history traits and chromosome integrity. Our results point to several possible reasons for this correlation, including the possibility that longer telomeres may be more adaptive in plants that have faster developmental rates (and therefore flower earlier). Our work suggests that chromosomal structure itself might be an adaptive trait associated with plant life-history strategies.

N95 mask reuse in a major urban hospital: COVID-19 response process and procedure.

BACKGROUND: The shortage of single-use N95 respirator masks (NRMs) during the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has prompted consideration of NRM recycling to extend limited stocks by healthcare providers and facilities. AIM: To assess potential reuse via autoclaving of NRMs worn daily in a major urban Canadian hospital. METHODS: NRM reusability was assessed following collection from volunteer staff after 2-8 h use, sterilization by autoclaving and PortaCount fit testing. A workflow was developed for reprocessing hundreds of NRMs daily. FINDINGS: Used NRMs passed fit testing after autoclaving once, with 86% passing a second reuse/autoclave cycle. A separate cohort of used masks pre-warmed before autoclaving passed fit testing. To recycle 200-1000 NRMs daily, procedures for collection, sterilization and re-distribution were developed to minimize particle aerosolization risk during NRM handling, to reject NRM showing obvious wear, and to promote adoption by staff. NRM recovery ranged from 49% to 80% across 12 collection cycles. CONCLUSION: Reuse of NRMs is feasible in major hospitals and other healthcare facilities. In sharp contrast to studies of unused NRMs passing fit testing after 10 autoclave cycles, we show that daily wear substantially reduces NRM fit, limiting reuse to a single cycle, but still increasing NRM stocks by ∼66%. Such reuse requires development of a comprehensive plan that includes communication across staffing levels, from front-line workers to hospital administration, to increase the collection, acceptance of and adherence to sterilization processes for NRM recovery.

A facile forward-genetic screen for Arabidopsis autophagy mutants reveals twenty-one loss-of-function mutations disrupting six ATG genes.

Macroautophagy is a process through which eukaryotic cells degrade large substrates including organelles, protein aggregates, and invading pathogens. Over 40 autophagy-related (ATG) genes have been identified through forward-genetic screens in yeast. Although homology-based analyses have identified conserved ATG genes in plants, only a few atg mutants have emerged from forward-genetic screens in Arabidopsis thaliana. We developed a screen that consistently recovers Arabidopsis atg mutations by exploiting mutants with defective LON2/At5g47040, a protease implicated in peroxisomal quality control. Arabidopsis lon2 mutants exhibit reduced responsiveness to the peroxisomally-metabolized auxin precursor indole-3-butyric acid (IBA), heightened degradation of several peroxisomal matrix proteins, and impaired processing of proteins harboring N-terminal peroxisomal targeting signals; these defects are ameliorated by preventing autophagy. We optimized a lon2 suppressor screen to expedite recovery of additional atg mutants. After screening mutagenized lon2-2 seedlings for restored IBA responsiveness, we evaluated stabilization and processing of peroxisomal proteins, levels of several ATG proteins, and levels of the selective autophagy receptor NBR1/At4g24690, which accumulates when autophagy is impaired. We recovered 21 alleles disrupting 6 ATG genes: ATG2/At3g19190, ATG3/At5g61500, ATG5/At5g17290, ATG7/At5g45900, ATG16/At5g50230, and ATG18a/At3g62770. Twenty alleles were novel, and 3 of the mutated genes lack T-DNA insertional alleles in publicly available repositories. We also demonstrate that an insertional atg11/At4g30790 allele incompletely suppresses lon2 defects. Finally, we show that NBR1 is not necessary for autophagy of lon2 peroxisomes and that NBR1 overexpression is not sufficient to trigger autophagy of seedling peroxisomes, indicating that Arabidopsis can use an NBR1-independent mechanism to target peroxisomes for autophagic degradation. Abbreviations: ATG: autophagy-related; ATI: ATG8-interacting protein; Col-0: Columbia-0; DSK2: dominant suppressor of KAR2; EMS: ethyl methanesulfonate; GFP: green fluorescent protein; IAA: indole-3-acetic acid; IBA: indole-3-butyric acid; ICL: isocitrate lyase; MLS: malate synthase; NBR1: Next to BRCA1 gene 1; PEX: peroxin; PMDH: peroxisomal malate dehydrogenase; PTS: peroxisomal targeting signal; thiolase: 3-ketoacyl-CoA thiolase; UBA: ubiquitin-associated; WT: wild type.

Deliberating performance targets workshop: Potential paths for emerging PM2.5 and O3 air sensor progress.

The United States Environmental Protection Agency held an international two-day workshop in June 2018 to deliberate possible performance targets for non-regulatory fine particulate matter (PM2.5) and ozone (O3) air sensors. The need for a workshop arose from the lack of any market-wide manufacturer requirement for Ozone documented sensor performance evaluations, the lack of any independent third party or government-based sensor performance certification program, and uncertainty among all users as to the general usability of air sensor data. A multi-sector subject matter expert panel was assembled to facilitate an open discussion on these issues with multiple stakeholders. This summary provides an overview of the workshop purpose, key findings from the deliberations, and considerations for future actions specific to sensors. Important findings concerning PM2.5 and O3 sensors included the lack of consistent performance indicators and statistical metrics as well as highly variable data quality requirements depending on the intended use. While the workshop did not attempt to yield consensus on any topic, a key message was that a number of possible future actions would be beneficial to all stakeholders regarding sensor technologies. These included documentation of best practices, sharing quality assurance results along with sensor data, and the development of a common performance target lexicon, performance targets, and test protocols.

Genotypes, phenotypes and whole genome sequence: Approaches from the My Life Our Future haemophilia project.

INTRODUCTION: Information from the genes encoding factor VIII (F8) and IX (F9) is used in reproductive planning and to inform inhibitor formation, bleeding severity and response to therapies. Advances in technology and our understanding of the human genome now allows more comprehensive methods to study genomic variation and its impact on haemophilia. AIMS: The My Life Our Future (MLOF) programme was begun in 2012 to provide genetic analysis and to expand research in haemophilia through a research repository. METHODS: MLOF enrolled haemophilia A and B patients followed at haemophilia treatment centers in the U.S., including, since 2015, known and potential genetic carriers. Initial F8 and F9 DNA analysis was performed utilizing a next generation sequencing approach which allowed simultaneous detection of F8 inversions and other variants. Candidate variants were confirmed using a second method and multiplex ligation-dependent probe amplification was used to detect structural variants. RESULTS: The initial phase of MLOF completed enrollment in December 2017 with 11,356 patients, genetic carriers, and potential carriers enrolled. In the 9453 subjects in whom analysis is complete, 687 unique previously unreported variants were found. Simultaneous sequencing of the F8 and F9 genes resulted in identification of non-deleterious variants previously reported as causative in haemophilia. DNA from 5141 MLOF subjects has undergone whole genome sequencing through the NHLBI TOPMed programme of the U.S. NIH. CONCLUSION: MLOF has provided genetic information for patients and their families to help inform clinical care and has established a repository of data and biospecimens to further advance haemophilia research.

Past, present and future of haemophilia gene therapy: From vectors and transgenes to known and unknown outcomes.

Since the 1960s, the pace of innovation in haemophilia treatment has been fast and furious and occasionally with unintended consequences. As newer technologies are harnessed to better treat, and potentially cure, haemophilias A and B, an understanding of their underlying scientific principles and their benefits and risks are essential for all stakeholders. This review summarizes the starts and stops of introducing FVIII and FIX transgenes clinically, beginning 20 years ago. Lessons from earlier nonclinical and clinical experiments have been utilized to improve vector selection, vector design, promoter/enhancer cis control regions and codon-optimized transgenes to trigger in vivo clinical FVIII and FIX levels in the near-normal to normal ranges. Many known and unknown questions remain, and some, based upon benefit and risk, should be answered during larger phase 3 clinical trials. Prior clinical outcomes in haemophilia trials have not been standardized, making between-trial comparisons difficult. Going forward, haemophilia gene therapy clinical trials should utilize a standard set of core outcomes, to facilitate comparisons to other gene- and protein-based therapies. These outcomes will be more important as the field moves beyond the first-generation gene therapies into more complex vectors that may address the shortcomings of first-generation vectors and offer greater benefits to the patient.

Core outcome set for gene therapy in haemophilia: Results of the coreHEM multistakeholder project.

BACKGROUND: Gene therapy trial results show potential to cure haemophilia A and haemophilia B. Securing broad access to a cure for a lifelong chronic disease is anticipated to face barriers at the individual and healthcare system levels, which can be partly mitigated by harmonized planning of clinical research studies. The aim of the coreHEM project was to determine the set of outcome measures required to evaluate efficacy, safety, comparative effectiveness and value of gene therapy for haemophilia. METHODS: Modified Delphi consensus process, based on methods adapted from the COMET Initiative. RESULTS: Forty-nine participants (five patients, five clinicians, five researchers, four regulators, three research agencies, six health technology assessors, nine payers and 12 drug developers) took part in the study, with over 90% participation. The frequency of bleeds, factor activity level, duration of expression, chronic pain, healthcare resource use and mental health were identified as the core outcomes to be measured in addition to regulatory-mandated adverse effects. CONCLUSIONS: For the first time in haemophilia, a core outcome set has been developed, with the involvement of representatives of all relevant stakeholder groups. The core set has been expanded to include outcomes supporting assessment of comparative effectiveness and value, with the goal of streamlining regulatory approval, health technology assessment and market access decisions. Patient involvement ensures that outcomes are meaningful and relevant to those living with haemophilia. Active dialogue among drug developers, regulators and payers throughout the process is expected to facilitate broad uptake of the core outcomes in forthcoming clinical trials.

First-year results of an expanded humanitarian aid programme for haemophilia in resource-constrained countries.

INTRODUCTION: The gaps in haemophilia treatment around the world are enormous; approximately 60% of an estimated 475 000 individuals are not identified. Of the 187 000 diagnosed, 30% (57 000) access clotting factor replacement therapy. Since 1996, humanitarian aid distributed by the World Federation of Hemophilia (WFH) has played a minor, yet vital role providing life-saving clotting factor to countries in emergency situations. Donated amounts have been small and sporadic, often salvaging short-dated products, providing little opportunity to leverage donations with governments. In 2015, a prospective donation programme of 100 million I.U. per year of extended half-life factor VIII and IX over 10 years was established, necessitating the development of new logistics and training programmes by WFH. AIM: To measure the impact of a greatly expanded haemophilia humanitarian aid program. MATERIALS AND METHODS: In 2016, the first full year of the expanded programme, WFH, distributed products to 58 countries with factor VIII usage <1 I.U. per capita, a level incompatible with long-term survival and far below the 4 I.U. FVIII per capita minimum established in Europe. RESULTS: The scope of the programme and utilization data for 2016 indicate primarily use for acute bleeding, orthopaedic and emergency surgeries. Compared to 2014, 2016 data showed substantial increases in patients served (5.9-fold, from 2119 to 14 579), surgeries performed (37-fold) and bleeds treated (6.9-fold). Patients on prophylaxis rose from 0 to 852, including 458 children under 10 years old. DISCUSSION: The expanded humanitarian aid programme impacts an estimated 10% of individuals with haemophilia previously unable to access treatment. CONCLUSION: This programme represents an unprecedented public-private partnership to deliver medicines to individuals with no access. Further, the programme offers the prospective opportunity to engage governments to take more responsiblity for increasing training, medical management, and product supply in 58 resource constrained countries.

Treatment of bleeding episodes with recombinant factor VIII Fc fusion protein in A-LONG study subjects with severe haemophilia A.

INTRODUCTION: The Phase 3 A-LONG study demonstrated the safety and efficacy of rFVIIIFc for the control and prevention of bleeding episodes in severe haemophilia A. AIM: To describe the treatment of bleeding episodes with rFVIIIFc in the A-LONG study. METHODS: A-LONG subjects (<1 IU dL-1 endogenous FVIII) were treated with individualized prophylaxis (Arm 1), weekly prophylaxis (Arm 2) or episodic treatment (Arm 3). Information recorded for each bleeding episode included type, location and dose to treat the episode. RESULTS: During A-LONG, 757 bleeding episodes occurred during the efficacy period; the majority [456 (60%)] occurred in Arm 3 (episodic treatment). Of 93 subjects in the prophylaxis arms who entered the study with target joints, 43 (60%) in Arm 1 and 11 (52%) in Arm 2 did not experience a target joint bleed. Overall, 98% of bleeding episodes (and 98% of bleeds involving a target joint) resolved with one or two infusions; the median dose per infusion to treat a bleed was 27 IU kg-1 (27 IU kg-1 for target joints). Using population pharmacokinetic simulations, FVIII activity levels were predicted to be below the upper limit of normal (150 IU dL-1 ) in most patients in the event that rFVIIIFc is used to treat a bleeding episode in close proximity to a prophylactic dose. CONCLUSIONS: These findings demonstrate the efficacy of rFVIIIFc for the treatment of acute bleeding episodes in subjects with severe haemophilia A, regardless of treatment regimen.

Changes in health-related quality of life with treatment of longer-acting clotting factors: results in the A-LONG and B-LONG clinical studies.

INTRODUCTION: In haemophilia, prophylactic infusion of replacement factor can result in improvements in health-related quality of life (HRQoL) when compared with episodic treatment. The Haemophilia-specific Quality of Life (Haem-A-QoL) questionnaire assessed HRQoL in adults with severe haemophilia A or B who received prophylactic or episodic treatment with recombinant factor VIII or IX Fc fusion protein (rFVIIIFc or rFIXFc) in the A-LONG or B-LONG clinical studies. AIMS: Understand changes in HRQoL during the A-LONG and B-LONG trials. METHODS: Group-level and individual-level changes over time for the Haem-A-QoL key domains of 'Physical Health' and 'Sports & Leisure,' and 'Total Score' were evaluated in adults through baseline and 6-month HRQoL assessments. Previously determined responder definitions (RDs) were used for evaluating meaningful subject-level HRQoL improvements. RESULTS: The analysis included 67 A-LONG and 51 B-LONG subjects who completed the Haem-A-QoL (baseline and 6 months). While HRQoL improvements were observed among all treatment groups, greater improvements in HRQoL were observed among subjects who received episodic treatment pre-study (and prophylaxis on-study) compared to those who received hyphenate prophylaxis. Applying the RDs for interpreting 6-month changes, 47.4%/33.3% ('Physical Health'), 35.9%/50.0% ('Sports & Leisure') and 23.9%/33.3% ('Total Score') of A-LONG subjects who received individualized or weekly prophylaxis were classified as HRQoL responders. In B-LONG, 69.2%/57.9% ('Physical Health'), 44.4%/56.7% ('Sports & Leisure') and 41.7%/44.1% ('Total Score') of subjects who received individualized or weekly prophylaxis were classified as HRQoL responders. CONCLUSION: Changes in Haem-A-QoL key domains and 'Total Score' suggest that prophylaxis with long-acting rFVIIIFc or rFIXFc resulted in meaningful HRQoL improvements.

Estimated aortic stiffness is independently associated with cardiac baroreflex sensitivity in humans: role of ageing and habitual endurance exercise.

We hypothesised that differences in cardiac baroreflex sensitivity (BRS) would be independently associated with aortic stiffness and augmentation index (AI), clinical biomarkers of cardiovascular disease risk, among young sedentary and middle-aged/older sedentary and endurance-trained adults. A total of 36 healthy middle-aged/older (age 55-76 years, n=22 sedentary and n=14 endurance-trained) and 5 young sedentary (age 18-31 years) adults were included in a cross-sectional study. A subset of the middle-aged/older sedentary adults (n=12) completed an 8-week-aerobic exercise intervention. Invasive brachial artery blood pressure waveforms were used to compute spontaneous cardiac BRS (via sequence technique), estimated aortic pulse wave velocity (PWV) and AI (AI, via brachial-aortic transfer function and wave separation analysis). In the cross-sectional study, cardiac BRS was 71% lower in older compared with young sedentary adults (P<0.05), but only 40% lower in older adults who performed habitual endurance exercise (P=0.03). In a regression model that included age, sex, resting heart rate, mean arterial pressure (MAP), body mass index and maximal exercise oxygen uptake, estimated aortic PWV (ß±s.e.=-5.76±2.01, P=0.01) was the strongest predictor of BRS (model R(2)=0.59, P<0.001). The 8-week-exercise intervention improved BRS by 38% (P=0.04) and this change in BRS was associated with improved aortic PWV (r=-0.65, P=0.044, adjusted for changes in MAP). Age- and endurance-exercise-related differences in cardiac BRS are independently associated with corresponding alterations in aortic PWV among healthy adults, consistent with a mechanistic link between variations in the sensitivity of the baroreflex and aortic stiffness with age and exercise.

Long-term safety and efficacy of recombinant factor VIII Fc fusion protein (rFVIIIFc) in subjects with haemophilia A.

INTRODUCTION: The safety, efficacy and prolonged half-life of recombinant factor VIII Fc fusion protein (rFVIIIFc) in previously treated patients with severe haemophilia A was demonstrated in the phase 3 A-LONG and Kids A-LONG studies. Here, we report interim safety and efficacy data from the rFVIIIFc extension study, ASPIRE (ClinicalTrials.gov #NCT01454739). METHODS: Eligible subjects could enrol in ASPIRE upon completing A-LONG or Kids A-LONG. There were four treatment groups: individualized prophylaxis; weekly prophylaxis; modified prophylaxis (for subjects in whom optimal treatment could not be achieved with individualized or weekly prophylaxis); and episodic treatment. The primary endpoint was development of inhibitors. RESULTS: A total of 150 A-LONG subjects and 61 Kids A-LONG subjects enrolled in ASPIRE. As of the interim data cut (6 January 2014), the median time on study was 80.9 (A-LONG) and 23.9 (Kids A-LONG) weeks. The majority of subjects (A-LONG, 92.0%; Kids A-LONG, 57.4%) had ≥100 cumulative rFVIIIFc exposure days. No inhibitors were observed. Adverse events were generally consistent with those expected in the general haemophilia A population. Median annualized bleeding rates (ABRs) were low with individualized [A-LONG: 0.66; Kids A-LONG: 0.00 (<6 years old), 1.54 (6 to <12 years old)], weekly (A-LONG: 2.03) and modified (A-LONG: 1.97) prophylaxis. There was no change in prophylactic infusion frequency or total weekly prophylactic dose in the majority of subjects from A-LONG and Kids A-LONG. CONCLUSION: Interim data from ASPIRE confirm the long-term safety of rFVIIIFc and the maintenance of a low ABR with extended-interval prophylactic dosing in patients with severe haemophilia A.

Pexophagy and peroxisomal protein turnover in plants.

Peroxisomes are dynamic, vital organelles that sequester a variety of oxidative reactions and their toxic byproducts from the remainder of the cell. The oxidative nature of peroxisomal metabolism predisposes the organelle to self-inflicted damage, highlighting the need for a mechanism to dispose of damaged peroxisomes. In addition, the metabolic requirements of plant peroxisomes change during development, and obsolete peroxisomal proteins are degraded. Although pexophagy, the selective autophagy of peroxisomes, is an obvious mechanism for executing such degradation, pexophagy has only recently been described in plants. Several recent studies in the reference plant Arabidopsis thaliana implicate pexophagy in the turnover of peroxisomal proteins, both for quality control and during functional transitions of peroxisomal content. In this review, we describe our current understanding of the occurrence, roles, and mechanisms of pexophagy in plants.