S-nitrosylation-triggered unfolded protein response maintains hematopoietic progenitors in Drosophila

The Drosophila lymph gland houses blood progenitors that give rise to myeloid-like blood cells. Initially, blood progenitors proliferate, but later, they become quiescent to maintain multipotency before differentiation. Despite the identification of various factors involved in multipotency maintenance, the cellular mechanism controlling blood progenitor quiescence remains elusive. Here, we identify the expression of nitric oxide synthase in blood progenitors, generating nitric oxide for post-translational S-nitrosylation of protein cysteine residues. S-nitrosylation activates the Ire1-Xbp1-mediated unfolded protein response, leading to G2 cell-cycle arrest. Specifically, we identify the epidermal growth factor receptor as a target of S-nitrosylation, resulting in its retention within the endoplasmic reticulum and blockade of its receptor function. Overall, our findings highlight developmentally programmed S-nitrosylation as a critical mechanism that induces protein quality control in blood progenitors, maintaining their undifferentiated state by inhibiting cell-cycle progression and rendering them unresponsive to paracrine factors.

Molecular traces of Drosophila hemocytes reveal transcriptomic conservation with vertebrate myeloid cells

Drosophila hemocytes serve as the primary defense system against harmful threats, allowing the animals to thrive. Hemocytes are often compared to vertebrate innate immune system cells due to the observed functional similarities between the two. However, the similarities have primarily been established based on a limited number of genes and their functional homologies. Thus, a systematic analysis using transcriptomic data could offer novel insights into Drosophila hemocyte function and provide new perspectives on the evolution of the immune system. Here, we performed cross-species comparative analyses using single-cell RNA sequencing data from Drosophila and vertebrate immune cells. We found several conserved markers for the cluster of differentiation (CD) genes in Drosophila hemocytes and validated the role of CG8501 (CD59) in phagocytosis by plasmatocytes, which function much like macrophages in vertebrates. By comparing whole transcriptome profiles in both supervised and unsupervised analyses, we showed that Drosophila hemocytes are largely homologous to vertebrate myeloid cells, especially plasmatocytes to monocytes/macrophages and prohemocyte 1 (PH1) to hematopoietic stem cells. Furthermore, a small subset of prohemocytes with hematopoietic potential displayed homology with hematopoietic progenitor populations in vertebrates. Overall, our results provide a deeper understanding of molecular conservation in the Drosophila immune system.

Accuracy of heart rate measured by military-grade wearable ECG monitor compared with reference and commercial monitors

INTRODUCTION

Physiological monitoring of soldiers can indicate combat readiness and performance. Despite demonstrated use of wearable devices for HR monitoring, commercial options lack desired military features. A newly developed OMNI monitor includes desired features such as long-range secure data transmission. This study investigated the accuracy of the OMNI to measure HR via accuracy of R-R interval duration relative to research-grade ECG and commercial products.

METHODS

54 healthy individuals (male/female=37/17, age=22.2±3.6 years, height=173.0±9.1 cm, weight=70.1±11.2 kg) completed a submaximal exercise test while wearing a reference ECG (Biopac) and a randomly assigned chest-based monitor (OMNI, Polar H10, Equivital EQ-02, Zephyr Bioharness 3). All participants also wore two wrist-based photoplethysmography (PPG) devices, Garmin fēnix 6 and Empatica E4. Bland-Altman analyses of agreement, concordance correlation coefficient (CCC) and root-mean-squared error (RMSE) were used to determine accuracy of the OMNI and commercial devices relative to Biopac. Additionally, a linear mixed-effects model evaluated the effects of device and exercise intensity on agreement.

RESULTS

Chest-based devices showed superior agreement with Biopac for measuring R-R interval compared with wrist-based ones in terms of mean bias, CCC and RMSE, with OMNI demonstrating the best scores on all metrics. Linear mixed-effects model showed no significant main or interaction effects for the chest-based devices. However, significant effects were found for Garmin and Empatica devices (p<0.001) as well as the interaction effects between both Garmin and Empatica and exercise intensity (p<0.001).

CONCLUSIONS

Chest-based ECG devices are preferred to wrist-based PPG devices due to superior HR accuracy over a range of exercise intensities, with the OMNI device demonstrating equal, if not superior, performance to other commercial ECG monitors. Additionally, wrist-based PPG devices are significantly affected by exercise intensity as they underestimate HR at low intensities and overestimate HR at high intensities.

Patient ratings in exercise therapy for the management of tendinopathy: a systematic review with meta-analysis

OBJECTIVE

To synthesise exercise therapy intervention data investigating patient rating outcomes for the management of tendinopathy.

DESIGN

A systematic review and meta-analysis of randomized controlled trials investigating exercise therapy interventions and reporting patient rating outcomes.

SETTING

Any setting in any country listed as very high on the human development index.

PARTICIPANTS

People with a diagnosis of any tendinopathy of any severity or duration.

INTERVENTIONS

Exercise therapy for the management of tendinopathy comprising five different therapy classes: 1) resistance; 2) plyometric; 3) vibration; 4) flexibility, and 5) movement pattern retraining modalities, were considered for inclusion.

MAIN OUTCOME MEASURES

Outcomes measuring patient rating of condition, including patient satisfaction and Global Rating of Change (GROC).

RESULTS

From a total of 124 exercise therapy studies, 34 (Achilles: 41%, rotator cuff: 32%, patellar: 15%, elbow: 9% and gluteal: 3%) provided sufficient information to be meta-analysed. The data were obtained across 48 treatment arms and 1246 participants. The pooled estimate for proportion of satisfaction was 0.63 [95%CrI: 0.53-0.73], and the pooled estimate for percentage of maximum GROC was 53 [95%CrI: 38-69%]. The proportion of patients reporting positive satisfaction and perception of change increased with longer follow-up periods from treatment onset.

CONCLUSION

Patient satisfaction and GROC appear similar and are ranked moderately high demonstrating that patients generally perceive exercise therapies positively. Further research including greater consistency in measurement tools is required to explore and where possible, identify patient- and exercise-related moderating factors that can be used to improve person-centred care.

SYSTEMATIC REVIEW REGISTRATION NUMBER

PROSPERO ID=CRD42020168187 CONTRIBUTION OF PAPER.

A Novel Interaction between MFN2/Marf and MARK4/PAR-1 Is Implicated in Synaptic Defects and Mitochondrial Dysfunction

As cellular energy powerhouses, mitochondria undergo constant fission and fusion to maintain functional homeostasis. The conserved dynamin-like GTPase, Mitofusin2 (MFN2)/mitochondrial assembly regulatory factor (Marf), plays a role in mitochondrial fusion, mutations of which are implicated in age-related human diseases, including several neurodegenerative disorders. However, the regulation of MFN2/Marf-mediated mitochondrial fusion, as well as the pathologic mechanism of neurodegeneration, is not clearly understood. Here, we identified a novel interaction between MFN2/Marf and microtubule affinity-regulating kinase 4 (MARK4)/PAR-1. In the Drosophila larval neuromuscular junction, muscle-specific overexpression of MFN2/Marf decreased the number of synaptic boutons, and the loss of MARK4/PAR-1 alleviated the synaptic defects of MFN2/Marf overexpression. Downregulation of MARK4/PAR-1 rescued the mitochondrial hyperfusion phenotype caused by MFN2/Marf overexpression in the Drosophila muscles as well as in the cultured cells. In addition, knockdown of MARK4/PAR-1 rescued the respiratory dysfunction of mitochondria induced by MFN2/Marf overexpression in mammalian cells. Together, our results indicate that the interaction between MFN2/Marf and MARK4/PAR-1 is fine-tuned to maintain synaptic integrity and mitochondrial homeostasis, and its dysregulation may be implicated in neurologic pathogenesis.

Development of Korea Neuroethics Guidelines

BACKGROUND

Advances in neuroscience and neurotechnology provide great benefits to humans though unknown challenges may arise. We should address these challenges using new standards as well as existing ones. Novel standards should include ethical, legal, and social aspects which would be appropriate for advancing neuroscience and technology. Therefore, the Korea Neuroethics Guidelines were developed by stakeholders related to neuroscience and neurotechnology, including experts, policy makers, and the public in the Republic of Korea.

METHOD

The guidelines were drafted by neuroethics experts, were disclosed at a public hearing, and were subsequently revised by opinions of various stakeholders.

RESULTS

The guidelines are composed of twelve issues; humanity or human dignity, individual personality and identity, social justice, safety, sociocultural prejudice and public communication, misuse of technology, responsibility for the use of neuroscience and technology, specificity according to the purpose of using neurotechnology, autonomy, privacy and personal information, research, and enhancement.

CONCLUSION

Although the guidelines may require a more detailed discussion after future advances in neuroscience and technology or changes in socio-cultural milieu, the development of the Korea Neuroethics Guidelines is a milestone for the scientific community and society in general for the ongoing development in neuroscience and neurotechnology.

Autophagy Plays a Crucial Role in Ameloblast Differentiation

Tooth enamel is generated by ameloblasts. Any failure in amelogenesis results in defects in the enamel, a condition known as amelogenesis imperfecta. Here, we report that mice with deficient autophagy in epithelial-derived tissues (K14-Cre;Atg7^F/F and K14-Cre;Atg3^F/F conditional knockout mice) exhibit amelogenesis imperfecta. Micro-computed tomography imaging confirmed that enamel density and thickness were significantly reduced in the teeth of these mice. At the molecular level, ameloblast differentiation was compromised through ectopic accumulation and activation of NRF2, a specific substrate of autophagy. Through bioinformatic analyses, we identified Bcl11b, Dlx3, Klk4, Ltbp3, Nectin1, and Pax9 as candidate genes related to amelogenesis imperfecta and the NRF2-mediated pathway. To investigate the effects of the ectopic NRF2 pathway activation caused by the autophagy deficiency, we analyzed target gene expression and NRF2 binding to the promoter region of candidate target genes and found suppressed gene expression of Bcl11b, Dlx3, Klk4, and Nectin1 but not of Ltbp3 and Pax9. Taken together, our findings indicate that autophagy plays a crucial role in ameloblast differentiation and that its failure results in amelogenesis imperfecta through ectopic NRF2 activation.

An XYZ-axis Matrix Approach for the Integration of Neuroscience and Neuroethics

The recent, unprecedented advancement in neuroscience has led to new discoveries about the human brain and its function. Yet at the same time, it has spurred novel ethical and regulatory issues, and the field of neuroethics has emerged as an interdisciplinary endeavor to address these issues. Across the globe, extensive efforts have been underway to achieve the integration of neuroscience and Neuroethics, with active engagement not only from academia but also from the government, the public, and industry. However, in some countries, integrating neuroscience and neuroethics has proved to be a particularly challenging task. For example, in South Korea, the government has primarily driven the integration effort, and only a small group of researchers is properly trained for conducting an interdisciplinary evaluation of ethical, legal, social, and cultural implications (ELSCI) of neurotechnology. On the basis of the last few years of experience pursuing a government-funded neuroethics project in South Korea, we developed a new operational framework to provide practical guidance on ELSCI research. This framework consists of the X, Y, and Z axes; the X-axis represents a target neurotechnology, the Y-axis represents different developmental stages of the technology, and the Z-axis represents ELSCI issues that may arise from the development and use of the neurotechnology. Here we also present a step-by-step workflow to apply this matrix framework, from organizing a panel for a target neurotechnology to facilitating stakeholder discussion through public hearings. This framework will enable meaningful integration of neuroscience and neuroethics to promote responsible innovation in neuroscience and neurotechnology.

Oral anticoagulation therapy in atrial fibrillation patients with advanced chronic kidney disease: CODE-AF Registry

Background and objectives

Advanced chronic kidney disease (CKD), including end-stage renal disease (ESRD) on dialysis, increases thromboembolic risk among patients with atrial fibrillation (AF). This study examined the comparative safety and efficacy of direct-acting oral anticoagulant (DOAC) compared to warfarin or no OAC among AF patients with advanced CKD or ESRD on dialysis.

Methods

Using data from the COmparison study of Drugs for symptom control and complication prEvention of AF (CODE-AF) registry, 260 non-valvular AF patients with advanced CKD (defined as estimated glomerular filtration rate [eGFR] &lt;3 0ml/min per 1.73 m2) or ESRD on dialysis were enrolled from June 2016 to July 2020. The study population was categorized into DOAC, warfarin, and no OAC group, and differences in major or clinically relevant non-major (CRNM) bleeding, stroke/systemic embolism (SE), myocardial infarction/critical limb ischemia (CLI), and death were assessed.

Results

During a median 24 months of follow-up, major or CRNM bleeding risk was significantly reduced in the DOAC group compared to the warfarin group (hazard ratio [HR] 0.21, 95% confidence interval [CI] 0.05 to 0.95, p=0.042). In addition, the risk of composite adverse clinical outcome (major or CRNM bleeding, stroke/SE, myocardial infarction/CLI, and death) was significantly reduced in the DOAC group compared to the no OAC group (HR 0.32, 95% CI 0.11 to 0.96, p=0.043).

Conclusion

Among AF patients with advanced CKD or ESRD on dialysis, DOAC was associated with a lower risk of major or CRNM bleeding compared to warfarin and a lower risk of composite adverse clinical outcome compared to no OAC.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Korean Healthcare Technology R&D project funded by the Ministry of Health & Welfare (HI15C1200, HC19C0130)

Measures to Use Electroceuticals and Secure Social Reliability in Korea: A Narrative Review

Background

The purpose of this study was to present a plan for utilizing electroceuticals to secure social reliability in Korea by investigating and analyzing the trends of humanities and social science research in Korea regarding electroceuticals.

Methods

The present situation of academic papers in the fields of humanities and social sciences that had researched electroceuticals in Korea and the topics that were directly related to electroceuticals had been reviewed and analyzed.

Results

Regarding researches related to electroceuticals in the fields of humanities and social sciences in Korea, they were insufficient quantitatively. Qualitatively, they had leaned too much toward theoretical and abstract discourses regarding neuroethics and neurophilosophy.

Conclusion

If researches in the fields of humanities and social sciences known to play a role in preparing practical guidelines could be carried out sufficiently while preparing a base for solving actual problems raised by electroceuticals, they could actually help plan a specific electroceuticals policy and a law to secure social reliability. Among principles of general life medical ethics (principles of biomedical ethics), when considering the principle of justice, the investment by the Korean government regarding research and development of electroceuticals, the rationalization of electroceuticals regulations, the application of electroceuticals of public health insurance benefit, and voluntary efforts of electroceuticals corporations are important in order to have strong plans for securing the social reliability of electroceuticals.

A new role for Hif-1α

A gene normally involved in responding to hypoxia helps to protect insect muscles during migratory flight in a non-oxygen dependent manner.

A Comparative Study on Intention to Use Digital Therapeutics: MZ Generation and Baby Boomers’ Digital Therapeutics Use Intention in Korea

Purpose: The aim of this study lies in articulating the relationship between digital literacy and private concern as a predictor of intention to use digital therapeutics. Materials and Methods: An online survey was conducted through a research company among 600 panels. The survey questionnaire consists of items of digital literacy, privacy concern, perceptions, and intention to use digital therapeutics, and the participants were asked to fill out the questions online. A structural equation model was established, and the difference in paths between the MZ generation and the baby boomers were examined. Results: Public perception of digital therapeutics was categorized into seven factors and the dimension of digital literacy as categorized into three factors. For the MZ generation, digital literacy and privacy concern both directly and indirectly affect the digital therapeutics use intention, in that higher the level of digital literacy and the lower the privacy concern, digital therapeutics perception and digital therapeutics use intention becomes intensified. For the baby boomers, digital literacy and privacy concern positively affect digital therapeutics perception, and as digital therapeutics perception becomes more positive, digital therapeutics use intention also increases. Direct effects of digital literacy and privacy concern to digital therapeutics use intention were not found for the baby boomers. Conclusion: In order to promote the use of digital therapeutics, it is common for the MZ generation and baby boomers to develop a positive perception toward digital therapeutics by cultivating digital literacy. For the MZ generation, privacy concerns need to be cautiously considered as they negatively affect the intention to use digital therapeutics.

Resting heart rate and cardiovascular outcomes in patients with atrial fibrillation: CODE-AF registry

Funding Acknowledgements

Type of funding sources: None.

Background

The prognostic significance of resting heart rate and its therapeutic target in atrial fibrillation (AF) is uncertain.

Purpose

The aim of this study was to investigate the relationships between resting heart rate and cardiovascular outcomes in patients with AF.

Methods

A total of 8,886 patients with AF was included from the COmparison study of Drugs for symptom control and complication prEvention of AF (CODE-AF) registry. Patients were categorized according to baseline heart rate, and cardiovascular outcomes were accessed during a median follow-up of 30 months. The primary outcome was a composite of cardiovascular death, hospitalization due to heart failure, and myocardial infarction/critical limb ischemia.

Results

Compared to heart rate ≥100 beats per minute (bpm), heart rate 80-99 bpm was associated with the lowest risk of primary outcome (adjusted hazard ratio [HR] 0.56, 95% confidence interval [CI] 0.40-0.79, p=0.001). In subgroup of patients with heart failure with preserved ejection fraction (HFpEF), heart rate between 80-99 bpm was associated with reduced risk of primary outcome compared to heart rate ≥100 bpm (HR 0.40, 95% CI 0.16-0.98, p=0.045). However, in patients with heart failure with reduced ejection fraction (HFrEF), there was no association between resting heart rate and cardiovascular outcomes (P for interaction 0.001).

Conclusion

Resting heart rate was associated with cardiovascular outcomes in patients with AF, and those with a resting heart rate between 80-99 bpm had the lowest risk of adverse events. The impact of resting heart rate on adverse events persisted in patients with concomitant HFpEF but was not apparent in those with concomitant HFrEF.

Impact of mapping technology on procedural characteristics during radiofrequency or cryoballoon pulmonary vein isolation for atrial fibrillation

Funding Acknowledgements

Type of funding sources: None.

Background/Introduction: Cryoballoon ablation (CBA) is often associated with shorter procedure times along with tradeoffs such as increased fluoroscopy use compared to radiofrequency (RF) ablation of atrial fibrillation (AF), however the impact of mapping technology on these characteristics is not fully understood.

Purpose

To assess the effect of mapping technology on trends in fluoroscopy use and procedure times in AF pulmonary vein isolation (PVI) procedures with an RF or CBA catheter.

Methods

Acute procedure data from 210 de novo AF cases using a 3D mapping system was prospectively collected from 48 centers in eight countries. Choice of technology was left to physician discretion; a PVI only ablation strategy was utilized in all cases. Procedure data such as total procedure and fluoroscopy times from cases using either an RF or CBA catheter with either a grid-style mapping catheter (HD Grid) or circular mapping catheter (CMC) were compared.

Results

Of the 210 cases, RF ablation was used in 103 (49%), and CBA used in 107 (51%). In RF cases, a relatively even split between CMC and HD Grid use was observed (n=46, 45% vs. n=57, 55%), while a CMC was used in 100% of CBA cases (Figure 1). Across all cases, fluoroscopy and procedure times were significantly shorter when HD Grid was used (7.4±26.7 minutes; 108.2±46.3 minutes) compared to a CMC (20.4±17.6 minutes; 133.7±62.7) (p&lt;0.001; p=0.003). A similar trend was also observed in RF cases using HD Grid (7.4±26.7 minutes; 108.2±46.3 minutes) compared to a CMC (17.9±12.3 minutes; 175.1±50.5) (p=0.01; p&lt;0.001). Fluoroscopy times in RF cases with HD Grid (7.4±26.7 minutes) were significantly shorter compared to CBA cases with a CMC (21.5±19.4 minutes) (p&lt;0.001), while procedure times were similar (108.2±46.3 minutes; 116.0±59.2 minutes, p=0.20).

Conclusion(s)

Use of HD Grid resulted in significantly shorter procedure and fluoroscopy times compared to a CMC across all cases, including those using RF ablation. Fluoroscopy times were also significantly shorter in RF cases using HD Grid compared to CBA cases using a CMC, with similar procedure times. These observations suggest that use of HD Grid may better enable safer and more efficient PVI, specifically when employing RF ablation, in addition to safer and equally efficient RF PVI compared to CBA with a CMC. Further study in in a larger, randomized cohort may be necessary.

Global preferences in mapping technology and its impact on fluoroscopy and procedure times during catheter ablation of atrial fibrillation

Funding Acknowledgements

Type of funding sources: None.

Background/Introduction

Choice in mapping technology may play a critical role in reducing fluoroscopy and procedure times during atrial fibrillation (AF) ablation, however this relationship is not well studied.

Purpose

To assess the impact of mapping technology on trends in fluoroscopy use and procedure times in AF ablation procedures.

Methods

Acute procedure data from 525 AF cases was prospectively collected from 68 centers in nine countries. Choice of technology and ablation strategy, including PVI and substrate modification, were left to physician discretion. Procedure data such as total procedure and fluoroscopy times from cases using a grid-style mapping catheter (HD Grid) were compared to those using a circular mapping catheter (CMC).

Results

Of the 525 cases, HD Grid was used in 230 (44%), and CMC was used in 295 (56%). HD Grid was routinely used for both de novo and redo procedures while CMC was used predominantly for de novo procedures (Table 1). Similar procedure times were noted in redo PAF and redo PersAF procedures, while significantly shorter procedure times were observed for the HD Grid group in both de novo PAF and PersAF (113.9±48.8 vs. 125.9±56.3 minutes, p=0.04; and 142.8±53.2 vs. 169.8±52.2 minutes, p=0.001).

Overall fluoroscopy times were significantly shorter using HD Grid compared to a CMC (9.0±19.6 minutes vs. 19.8±16.4 minutes, p&lt;0.001), including significantly shorter fluoroscopy times in de novo PAF, de novo PersAF, and redo PAF (Table 1). There were 155 cases completed without fluoroscopy use; zero fluoroscopy cases accounted for 50% (114/230) and 14% (41/295) of total cases completed with HD Grid and a CMC, respectively (p&lt;0.001).

Conclusion(s)

Use of HD Grid was observed in a significantly higher portion of zero fluoroscopy cases and resulted in significantly shorter procedure and fluoroscopy times in both de novo PAF and de novo PersAF and significantly shorter fluoroscopy times in redo PAF. These observations suggest that use of HD Grid may better enable faster and safer procedures in these specific AF types compared to CMCs, although further analysis in a larger, randomized cohort may be warranted.

Intrinsic and Extrinsic Regulation of Hematopoiesis in Drosophila

Drosophila melanogaster lymph gland, the primary site of hematopoiesis, contains myeloid-like progenitor cells that differentiate into functional hemocytes in the circulation of pupae and adults. Fly hemocytes are dynamic and plastic, and they play diverse roles in the innate immune response and wound healing. Various hematopoietic regulators in the lymph gland ensure the developmental and functional balance between progenitors and mature blood cells. In addition, systemic factors, such as nutrient availability and sensory inputs, integrate environmental variabilities to synchronize the blood development in the lymph gland with larval growth, physiology, and immunity. This review examines the intrinsic and extrinsic factors determining the progenitor states during hemocyte development in the lymph gland and provides new insights for further studies that may extend the frontier of our collective knowledge on hematopoiesis and innate immunity.

Fly Cell Atlas: A single-nucleus transcriptomic atlas of the adult fruit fly

For more than 100 years, the fruit fly Drosophila melanogaster has been one of the most studied model organisms. Here, we present a single-cell atlas of the adult fly, Tabula Drosophilae, that includes 580,000 nuclei from 15 individually dissected sexed tissues as well as the entire head and body, annotated to >250 distinct cell types. We provide an in-depth analysis of cell type-related gene signatures and transcription factor markers, as well as sexual dimorphism, across the whole animal. Analysis of common cell types between tissues, such as blood and muscle cells, reveals rare cell types and tissue-specific subtypes. This atlas provides a valuable resource for the Drosophila community and serves as a reference to study genetic perturbations and disease models at single-cell resolution.

Menstrual Cycle Control - A Controversial Example of Human Enhancement in Relation to Women's Body and Psyche

By discussing the position of bio-conservatism and transhumanism, we question if the women menstrual cycle control would represent a new way toward a more responsive relation with one's own physical and mental health, a choice of freedom from undesired physiological conditions, a medicalization of a natural physiological event or an innovative carrier of social stigma against the women. We argue that the advancement of medical science may allow women a choice if to regulate own menstrual cycle, offering them as well a right to intervene responsibly on their own body and psyche. Accordingly, a post-human society could provide a suitable coexistence between women who claim menstruation as the biological essence and those who claim it as an option.

Chk2-p53 and JNK in irradiation-induced cell death of hematopoietic progenitors and differentiated cells in Drosophila larval lymph gland

Ionizing radiation (IR) induces DNA double-strand breaks that activate the DNA damage response (DDR), which leads to cell cycle arrest, senescence, or apoptotic cell death. Understanding the DDR of stem cells is critical to tissue homeostasis and the survival of the organism. Drosophila hematopoiesis serves as a model system for sensing stress and environmental changes; however, their response to DNA damage remains largely unexplored. The Drosophila lymph gland is the larval hematopoietic organ, where stem-like progenitors proliferate and differentiate into mature blood cells called hemocytes. We found that apoptotic cell death was induced in progenitors and hemocytes after 40 Gy irradiation, with progenitors showing more resistance to IR-induced cell death compared to hemocytes at a lower dose. Furthermore, we found that Drosophila ATM (tefu), Chk2 (lok), p53, and reaper were necessary for IR-induced cell death in the progenitors. Notably, IR-induced cell death in mature hemocytes required tefu, Drosophila JNK (bsk), and reaper, but not lok or p53. In summary, we found that DNA damage induces apoptotic cell death in the late third instar larval lymph gland and identified lok/p53-dependent and -independent cell death pathways in progenitors and mature hemocytes, respectively.

Metabolic control of cellular immune-competency by odors in Drosophila

Studies in different animal model systems have revealed the impact of odors on immune cells; however, any understanding on why and how odors control cellular immunity remained unclear. We find that Drosophila employ an olfactory-immune cross-talk to tune a specific cell type, the lamellocytes, from hematopoietic-progenitor cells. We show that neuronally released GABA derived upon olfactory stimulation is utilized by blood-progenitor cells as a metabolite and through its catabolism, these cells stabilize Sima/HIFα protein. Sima capacitates blood-progenitor cells with the ability to initiate lamellocyte differentiation. This systemic axis becomes relevant for larvae dwelling in wasp-infested environments where chances of infection are high. By co-opting the olfactory route, the preconditioned animals elevate their systemic GABA levels leading to the upregulation of blood-progenitor cell Sima expression. This elevates their immune-potential and primes them to respond rapidly when infected with parasitic wasps. The present work highlights the importance of the olfaction in immunity and shows how odor detection during animal development is utilized to establish a long-range axis in the control of blood-progenitor competency and immune-priming.

Depression and risk of atrial fibrillation: a nationwide population-based study

Background

Although treatments of atrial fibrillation (AF) based on the biological mechanisms for initiation and maintenance of AF improve cardiovascular outcomes, psychosocial factors have been also implicated in the etiology and progression of cardiovascular disease.

Objective

We aimed to evaluate the association between depression and incident AF using nationwide database from the National Health Insurance Service in South Korea.

Methods

A total of 9,075,224 participants with data of national health checkup in 2009 were included, and participants who were diagnosed with AF before the examination were excluded. Exposure to depression is determined by the precedence of depression diagnosed within 2 years.

Results

Depression was diagnosed in 1.37% (124,709) of participants at baseline. Compared to the non-depression group, depression group was likely to be female and had higher comorbidities. After adjusting covariates, depression group had a higher risk of incident AF compared with non-depression group (hazard ratio, 1.30; 95% confidence interval, 1.26–1.34). Repeated exposure to depression increased a risk of incident AF (Figure 1).

Conclusion

Depression was associated with an increased risk of new-onset AF. This association was stronger for patients who had more burden of depression. Future studies should investigate whether early treatment of depression can prevent incident AF.

Figure 1

Funding Acknowledgement

Type of funding source: None

Single-cell transcriptome maps of myeloid blood cell lineages in Drosophila

The Drosophila lymph gland, the larval hematopoietic organ comprised of prohemocytes and mature hemocytes, has been a valuable model for understanding mechanisms underlying hematopoiesis and immunity. Three types of mature hemocytes have been characterized in the lymph gland: plasmatocytes, lamellocytes, and crystal cells, which are analogous to vertebrate myeloid cells, yet molecular underpinnings of the lymph gland hemocytes have been less investigated. Here, we use single-cell RNA sequencing to comprehensively analyze heterogeneity of developing hemocytes in the lymph gland, and discover previously undescribed hemocyte types including adipohemocytes, stem-like prohemocytes, and intermediate prohemocytes. Additionally, we identify the developmental trajectory of hemocytes during normal development as well as the emergence of the lamellocyte lineage following active cellular immunity caused by wasp infestation. Finally, we establish similarities and differences between embryonically derived- and larval lymph gland hemocytes. Altogether, our study provides detailed insights into the hemocyte development and cellular immune responses at single-cell resolution.

How the Drosophila lymph gland hemocytes develop and are regulated at a single-cell level is unclear. Here, the authors use single-cell RNA sequencing to show heterogeneity of developing hemocytes in the lymph gland and how they react to wasp infestation, and compare hemocytes from two independent origins.

Introducing mobile fracture prevention services with DXA in Northern Scotland: a comparative study of three rural communities

Mobile fracture prevention services, with DXA, significantly improved access to care for those at high risk of fracture living in rural areas. Introduction of mobile services facilitated access to fracture liaison services and development of integrated of care pathways across community- and secondary-based care.

INTRODUCTION

The ageing population is growing faster in rural areas, yet most fracture prevention services are located in urban areas. As part of a wider study, evaluating the introduction of mobile fracture prevention services, we focus on whether mobile services improve access to care for those at highest risk of fracture.

METHODS

Services outcomes were assessed against the Royal Osteoporosis Society clinical standards for fracture liaison services. This included standardised, age-specific referral rates, FRAX 10-year probability of major osteoporotic and hip fracture of referrals, pre- and post-introduction of the mobile service across two island and one rural mainland sites. This was compared with referrals from a similar rural mainland region with local access to a comprehensive service.

RESULTS

Greatest impact occurred in areas with most limited service provision at baseline. Mean age of patients referred increased from 59 to 68 years (CI 6.8-10.1, p < 0.001). Referral rates increased from 2.8 to 5.4 per 1000 population between 2011 and 2018, with a 5-fold rise in those ≥ 75 years (0.4 to 2.0 per 1000). Mean FRAX 10-year risk of major osteoporotic fracture increased from 12.7 to 17.7% (CI 3.2-5.7, p < 0.001). Mean hip fracture risk probability increased from 3.0 to 5.7% (CI 2.0-3.4, p < 0.001). However, referral rates from the mobile sites remained lower than the comparator site.

CONCLUSIONS

Mobile fracture prevention services, including DXA, greatly improved uptake amongst high-risk individuals. Mobile services facilitated development of integrated of care pathways, including fracture liaison services, across community- and secondary-based care.

A single-cell survey of Drosophila blood

Drosophila blood cells, called hemocytes, are classified into plasmatocytes, crystal cells, and lamellocytes based on the expression of a few marker genes and cell morphologies, which are inadequate to classify the complete hemocyte repertoire. Here, we used single-cell RNA sequencing (scRNA-seq) to map hemocytes across different inflammatory conditions in larvae. We resolved plasmatocytes into different states based on the expression of genes involved in cell cycle, antimicrobial response, and metabolism together with the identification of intermediate states. Further, we discovered rare subsets within crystal cells and lamellocytes that express fibroblast growth factor (FGF) ligand branchless and receptor breathless, respectively. We demonstrate that these FGF components are required for mediating effective immune responses against parasitoid wasp eggs, highlighting a novel role for FGF signaling in inter-hemocyte crosstalk. Our scRNA-seq analysis reveals the diversity of hemocytes and provides a rich resource of gene expression profiles for a systems-level understanding of their functions.

Copper-doped ZrO2 nanoparticles as high-performance catalysts for efficient removal of toxic organic pollutants and stable solar water oxidation

Doping effect on the photoelectrochemical (PEC) water splitting efficiency and photocatalytic activities of ZrO₂ under visible light are reported. The XRD analysis revealed that pure, 0.1 and 0.3 mol% doped samples showed mixed crystal phases (tetragonal and monoclinic) and 0.5 mol% doped sample showed a pure tetragonal phase. Under visible light, 90% of methyl orange dye degradation was achieved with in 100 min. Moreover, the optimal doped sample showed a significant degradation rate constant over other samples. The doped photoelectrodes display a better PEC water oxidation performance over pure photoelectrode. Furthermore, the optimal doped (0.3 mol %) electrode shows 0.644 mAcm^-2 photocurrent density, corresponding to an approximate 50-fold enhancement over pure electrode (0.013 mAcm^-2). The optimized doped sample achieved 98% degradation of methyl orange within 100 min of light irradiation. The superior PEC water oxidation and photocatalytic activity of optimal doped samples under visible light are credited to suitable doping content, crystalline size, greater surface area, suitable bandgap, a lower charge carrying resistance, surface properties and the ability for decreasing the charge carrier's recombination rate.

The Role of Lozenge in Drosophila Hematopoiesis

Drosophila hematopoiesis is comparable to mammalian differentiation of myeloid lineages, and therefore, has been a useful model organism in illustrating the molecular and genetic basis for hematopoiesis. Multiple novel regulators and signals have been uncovered using the tools of Drosophila genetics. A Runt domain protein, lozenge, is one of the first players recognized and closely studied in the hematopoietic lineage specification. Here, we explore the role of lozenge in determination of prohemocytes into a special class of hemocyte, namely the crystal cell, and discuss molecules and signals controlling the lozenge function and its implication in immunity and stress response. Given the highly conserved nature of Runt domain in both invertebrates and vertebrates, studies in Drosophila will enlighten our perspectives on Runx-mediated development and pathologies.

Subpopulation of Macrophage-Like Plasmatocytes Attenuates Systemic Growth via JAK/STAT in the Drosophila Fat Body

Drosophila hemocytes, like those of mammals, are given rise from two distinctive phases during both the embryonic and larval hematopoiesis. Embryonically derived hemocytes, mostly composed of macrophage-like plasmatocytes, are largely identified by genetic markers. However, the cellular diversity and distinct functions of possible subpopulations within plasmatocytes have not been explored in Drosophila larvae. Here, we show that larval plasmatocytes exhibit differential expressions of Hemolectin (Hml) and Peroxidasin (Pxn) during development. Moreover, removal of plasmatocytes by overexpressing pro-apoptotic genes, hid and reaper in Hml-positive plasmatocytes, feeding high sucrose diet, or wasp infestation results in increased circulating hemocytes that are Hml-negative. Interestingly these Hml-negative plasmatocytes retain Pxn expression, and animals expressing Hml-negative and Pxn-positive subtype largely attenuate growth and abrogate metabolism. Furthermore, elevated levels of a cytokine, unpaired 3, are detected when Hml-positive hemocytes are ablated, which in turn activates JAK/STAT activity in several tissues including the fat body. Finally, we observed that insulin signaling is inhibited in this background, which can be recovered by concurrent loss of upd3. Overall, this study highlights heterogeneity in Drosophila plasmatocytes and a functional plasticity of each subtype, which reaffirms extension of their role beyond immunity into metabolic regulation for cooperatively maintaining internal homeostatic balance.

Lilac flower-shaped ZnCo2O4electrocatalyst for efficient methanol oxidation and oxygen reduction reactions in an alkaline medium

A ZnCo₂O₄electrocatalyst for the efficient MOR and ORR.

P2860The effects of single nucleotide polymorphisms in Korean patients with early-onset lone atrial fibrillation after catheter ablation

Background

The status of SNPs among patients with extremely early-onset lone AF and the association with outcome of catheter ablation has not been evaluated before. This study evaluated the status of single nucleotide polymorphisms (SNPs) in Korean patients with early-onset (<40 years old) lone AF and effects on the outcome after catheter ablation.

Methods

A total of 89 consecutive patients (mean age 35.7±3.7 years, 81 males) with drug-refractory AF (paroxysmal 64.0%) who underwent catheter ablation were included. Sixteen SNPs including rs13376333, rs10465885, rs10033464, rs2200733, rs17042171, rs6843082, rs7193343, rs2106261, rs17570669, rs853445, rs11708996, rs6800541, rs251253, rs3807989, rs11047543 and rs3825214 were genotyped. Serial 48-day Holter electrocardiographic recordings were acquired to detect AF recurrences during long-term follow up.

Results

Wild type of rs7193343 [CC; 0/7 (0%) vs. CT; 22/40 (55.0%) vs. TT; 18/41 (43.9%), p=0.025] and rs11047543 [GG; 26/69 (37.7%) vs. GA; 13/18 (72.2%) vs. AA; 0/0, p=0.009] and homozygous variant of rs3825214 [AA; 16/31 (51.6%) vs. AG; 22/43 (51.2%) vs. GG; 2/13 (15.4%), p=0.05] were significantly associated with lower rate of late recurrence. When the patients were assigned to four groups according to the number of risk alleles (n=0–3), Kaplan-Meier survival analysis showed incremental prognostic value according to the number of variant alleles (p=0.002) (Figure 1).

Figure 1

Conclusions

Polymorphisms on rs7193343, rs3825214 and rs11047543 modulate the risk for AF recurrence after catheter ablation during long term follow up in Korean patients with early-onset lone AF.

Acknowledgement/Funding

Korean Society of Cardiology

P1026Risk factors for the occurrence of stroke after atrial fibrillation ablation

Background

Risk factors for the occurrence of embolic stroke (ES) after atrial fibrillation (AF) ablation have not been fully elucidated. Our aim was to assess incidence of ES during long-term follow-up following AF ablation and to identify predicting factors associated with post-ablation ES.

Methods

We enrolled patients who experienced ES after AF ablation and body mass index-matched controls from AF ablation registries. Epicardial adipose tissue (EAT) was assessed using multislice computed tomography prior to ablation.

Results

A total of 3,464 patients who underwent AF ablation were recruited. During a mean follow-up of 47.2 months, ES occurred in 47 patients (1.36%) with a mean CHA2DS2-VAS score of 2.15 and overall incidence of ES was 0.34 per 100 patients/year. Compared with control group (n=190), ES group had more higher prior thromboembolic event and AF recurrence rates, larger LA size, lower creatinine clearance rate (CCr), and greater total and periatrial EAT volumes although no differences in AF type, CHA2DS2-VASc score, ablation extent, and anti-thrombotics use were found. On multivariate regression analysis, a prior history of thromboembolism, CCr, and periatrial EAT volume were independently associated with ES occurrence after AF ablation.

Cox regression analysis Risk factor Univariate Multivariate HR (95% CI) p value HR (95% CI) p value Age 1.017 (0.984–1.051) 0.31 Prior thromboembolism 2.488 (1.134–5.460) 0.023 2.916 (1.178–7.219) 0.021 CHA2DS2-VASc score 1.139 (0.899–1.445) 0.282 CCr 0.984 (0.970–0.999) 0.038 0.982 (0.996–0.998) 0.029 LA diameter (mm) 1.070 (1.012–1.130) 0.017 1.072 (0.999–1.150) 0.054 EAT_total (ml) 1.020 (1.010–1.029) <0.001 1.008 (0.993–1.023) 0.297 EAT_periatrial (ml) 1.085 (1.045–1.126) <0.001 1.065 (1.005–1.128) 0.032 PVI + additional ablation 0.846 (0.460–1.557) 0.592 No anticoagulant use 0.651 (0.346–1.226) 0.184 Recurrence 2.011 (1.007–4.013) 0.048 1.240 (0.551–2.793) 0.603 CCr, creatinine clearance rate; EAT, epicardial adipose tissue; LA, left atrium; PVI, pulmonary vein isolation.

K-M curve for stroke-free survival

Conclusions

Incidence of ES after AF ablation was lower than expected rate based on CHA2DS2-VASc score even though anticoagulants use was limited. Periatrial EAT volume, a prior thromboembolism event, and CCr were independent factors in predicting ES irrespective of AF recurrence and CHA2DS2-VASc score in patients who underwent AF ablation.

P3762The impact of type and burden of atrial fibrillation on stroke occurrence in patients with atrial fibrillation: from a prospective cohort of atrial fibrillation patients (CODE-AF Registry)

Background and purpose

Although several studies reported that stroke risk in patients with paroxysmal atrial fibrillation (AF) is similar to those with persistent or permanent AF, there is still controversy on the relationship of AF type and stroke occurrence. We investigated the effect of AF type on AF burden and stroke risk in patients with non-valvular AF.

Methods

Within the CODE-AF prospective, outpatient registry (COmparison study of Drugs for symptom control and complication prEvention of Atrial Fibrillation), we identified 8,883 patients ≥18 years of age with non-valvular AF and eligible follow-up visits. We compared AF burden and stroke risk among patients with 3 types of AF: paroxysmal (n=5,808) or persistent (n=2,806) or permanent (n=269).

Results

The median age of the overall population was 68.0 (interquartile range, 60.0–75.0); 36.0% were female. Patients with persistent and permanent AF were older and had higher CHA2DS2-VASc scores and anticoagulation rate than those with paroxysmal AF. Compared with permanent AF (5.2±16.4%), the arrhythmic burden of AF on 24hrs Holter monitoring was significantly lower in paroxysmal AF (2.1±7.2%, p<0.001) and persistent AF (2.0±7.5%, p<0.001). During median follow-up period of 1.38 years (interquartile range: 0.96–1.67), total 82 (0.92%) patients experienced ischemic stroke with incidence rates of 0.51, 1.04 and 1.69 events per 100 person-years for paroxysmal, persistent and permanent AF, respectively. Compared with paroxysmal AF, the risk of ischemic stroke was increased in persistent AF with clinical variable adjusted hazard ratio (aHR) of 1.94 (95% confidence intervals [CI], 1.23–3.07; P=0.005) and permanent AF with aHR of 2.64 (95% CI, 1.09–6.41; P=0.03).

AF type and HR of stroke occurrence Paroxysmal (n=5,808) Persistent (n=2,806) Permanent (n=269) Stoke events 39 37 6 Person years (PYs) 7673 3544 356 /100 PYs 0.51 1.04 1.69 HR (95% CI), p-value HR (95% CI), p-value HR (95% CI), p-value Unadjusted HR 1 (Reference) 2.05 (1.27–3.31), 0.003 3.32 (1.15–7.90), 0.02 Clinical variables adjusted HR 1 (Reference) 1.94 (1.23–3.07), 0.005 2.64 (1.09–6.41), 0.03 PYs: Person years; HR: Hazard ratio.

Conclusion

Persistent and permanent AF was associated with the increased risk of stroke than paroxysmal AF, after adjustment of clinical variables including age, sex, comorbidities and anticoagulation rate. These results suggest that AF type and burden might be related with the risk of ischemic stroke and should be considered in the stroke prevention of AF.

P11.32 Combined effects of niclosamide and temozolomide against human glioblastoma tumorspheres

BACKGROUND

Glioblastoma (GBM) is the most aggressive type of brain tumor and has poor survival outcomes, even after a combination of surgery, radiotherapy, and chemotherapy. Temozolomide is the only agent that has been shown to be effective against GBM, suggesting that combination of temozolomide with other agents may be more effective. Niclosamide, an FDA approved anthelmintic agent, has shown anti-cancer effects against human colon, breast, prostate cancers as well as GBM. However, the efficacy of the combination of niclosamide with temozolomide against GBM tumorspheres (TSs) has not been determined. We hypothesized that the combined treatment could effectively suppress GBM TSs.

MATERIAL AND METHODS

Effects of niclosamide and/or temozolomide on GBM TSs were evaluated. Viability, stemness, and invasive properties of GBM TSs were examined. In vivo anticancer efficacy was tested in a mouse orthotopic xenograft model.

RESULTS

The combination of niclsoamide and temozolomide significantly inhibited the viability, sphere formation, expression of stemness-related proteins, and invasive properties of GBM TSs. This combination significantly down-regulated the expression of epithelial mesenchymal transition-related proteins. Bioluminescence imaging further showed that compared with either agent alone, combination of niclosamide and temozolomide significantly reduced the tumor burden in orthotopic xenograft models.

CONCLUSION

The combination of niclosamide and temozolomide effectively decreased the stemness and invasive properties of GBM TSs, suggesting that this regimen may be therapeutically effective in treating patients with GBM.

Comparative responsiveness of the PROMIS-10 Global Health and EQ-5D questionnaires in patients undergoing total knee arthroplasty

AIMS

Responsiveness to clinically important change is a key feature of any outcome measure. Throughout Europe, health-related quality of life following total knee arthroplasty (TKA) is routinely measured with EuroQol five-dimension (EQ-5D) questionnaires. The Patient-Reported Outcomes Measurement Information System 10-Question Short-Form (PROMIS-10 Global Health) score is a new general heath outcome tool which is thought to offer greater responsiveness. Our aim was to compare these two tools.

PATIENTS AND METHODS

We accessed data from a prospective multicentre cohort study in the United Kingdom, which evaluated outcomes following TKA. The median age of the 721 patients was 69.0 years (interquartile range, 63.3 to 74.6). There was an even division of sex, and approximately half were educated to secondary school level. The preoperative EQ-5D, PROMIS-10, and Oxford Knee Scores (OKS) were available and at three, six, and 12 months postoperatively. Internal responsiveness was assessed by standardized response mean (SRM) and effect size (Cohen's d). External responsiveness was assessed by correlating change scores of the EQ-5D and PROMIS-10, with the minimal clinically important difference (MCID) of the OKS. Receiver operating characteristic (ROC) curves were used to assess the ability of change scores to discriminate between improved and non-improved patients.

RESULTS

All measures showed significant changes between the preoperative score and the various postoperative times (p < 0.001). Most improvement occurred during the first three months, with small but significant changes between three and six months, and no further change between six and 12 months postoperatively. SRM scores for EQ-5D, PROMIS-10, and OKS were large (> 0.8). ROC curves showed that both EQ-5D and PROMIS-10 were able to discriminate between patients who achieved the OKS MCID and those who did not (area under the curve (AUC) of 0.7 to 0.82).

CONCLUSION

The PROMIS-10 physical health tool showed greater responsiveness to change than the EQ-5D, most probably due to the additional questions on physical health parameters that are more susceptible to modification following TKA. The EQ-5D was, however, shown to be sensitive to clinically meaningful change following TKA, and provides the additional ability to calculate health economic utility scores. It is likely, therefore, that EQ-5D will continue to be the global health metric of choice in the United Kingdom. Cite this article: Bone Joint J 2019;101-B:832-837.

Systematic review and meta-analysis on outcomes of salvage therapy in patients with tumour recurrence during 'watch and wait' in rectal cancer

INTRODUCTION

The 'watch and wait' approach has recently emerged as an alternative approach for managing patients with complete clinical response in rectal cancer. However, less is understood whether the intervention is associated with a favourable outcome among patients who require salvage therapy following local recurrence.

MATERIALS AND METHODS

A comprehensive systematic search was performed using EMBASE, PubMed, MEDLINE, Journals@Ovid as well as hand searches; published between 2004 and 2018, to identify studies where outcomes of patients undergoing watch and wait were compared with conventional surgery. Study quality was assessed using the Newcastle-Ottawa assessment scale. The main outcome was relative risks for overall and disease specific mortality in salvage therapy.

RESULTS

Nine eligible studies were included in the meta-analysis. Of 248 patients who followed the watch and wait strategy, 10.5% had salvage therapy for recurrent disease. No statistical heterogeneity was found in the results. The relative risk of overall mortality in the salvage therapy group was 2.42 (95% confidence interval 0.96-6.13) compared with the group who had conventional surgery, but this was not statistically significant (P > 0.05). The relative risk of disease specific mortality in salvage therapy was 2.63 (95% confidence interval 0.81-8.53).

CONCLUSION

Our findings demonstrated that there was no significant difference in overall and disease specific mortality in patients who had salvage treatment following recurrence of disease in the watch and wait group compared with the standard treatment group. However, future research into the oncological safety of salvage treatment is needed.

Systemic control of immune cell development by integrated carbon dioxide and hypoxia chemosensation in Drosophila

Drosophila hemocytes are akin to mammalian myeloid blood cells that function in stress and innate immune-related responses. A multi-potent progenitor population responds to local signals and to systemic stress by expanding the number of functional blood cells. Here we show mechanisms that demonstrate an integration of environmental carbon dioxide (CO2) and oxygen (O2) inputs that initiate a cascade of signaling events, involving multiple organs, as a stress response when the levels of these two important respiratory gases fall below a threshold. The CO2 and hypoxia-sensing neurons interact at the synaptic level in the brain sending a systemic signal via the fat body to modulate differentiation of a specific class of immune cells. Our findings establish a link between environmental gas sensation and myeloid cell development in Drosophila. A similar relationship exists in humans, but the underlying mechanisms remain to be established.

Support Vector Machine Quantile Regression for Detecting Differentially Expressed Genes in Microarray Analysis

Objectives: One of the main objectives of microarray analysis is to identify genes differentially expressed under two distinct experimental conditions. This task is complicated by the noisiness of data and the large number of genes that are examined. Fold change (FC) based gene selection often misleads because error variability for each gene is heterogeneous in different intensity ranges. Several statistical methods have been suggested, but some of them result in high false positive rates because they make very strong parametric assumptions.

Methods: We present support vector quantile regression (SVMQR) using iterative reweighted least squares (IRWLS) procedure based on the Newton method instead of usual quadratic programming algorithms. This procedure makes it possible to derive the generalized approximate cross validation (GACV) method for choosing the parameters which affect the performance of SVMAR. We propose SVMQR based on a novel method for identifying differentially expressed genes with a small number of replicated microarrays.

Results: We applied SVMQR to both three biological dataset and simulated dataset and showed that it performed more reliably and consistently than FC-based gene selection, Newton’s method based on the posterior odds of change, or the nonparametric t-test variant implemented in significance analysis of microarrays (SAM).

Conclusions: The SVMQR method was an exploratory method for cDNA microarray experiments to identify genes with different expression levels between two types of samples (e.g., tumor versus normal tissue). The SVMQR method performed well in the situation where error variability for each gene was heterogeneous in intensity ranges.

Measuring Sarcopenia Severity in Older Adults and the Value of Effective Interventions

OBJECTIVES

Little is known about the severity and long-term health and economic consequences of sarcopenia. We developed a sarcopenia index to measure severity in older Americans and estimated the long-term societal benefits generated by effective interventions to mitigate severity.

DESIGN

Using a micro-simulation model, we quantified the potential societal value generated in the US in 2010-2040 by reductions in sarcopenia severity in older adults. All analyses were performed in Stata and SAS.

SETTING AND PARTICIPANTS

Secondary data from the National Health and Nutrition Examination Survey (NHANES) (N = 1634) and Health and Retirement Study (HRS) (N = 952) were used to develop a sarcopenia severity index in older adults.

MEASUREMENTS

Multi-trait multi-method and factor analyses were used to validate and calibrate the sarcopenia severity index, which was modeled as a function of gait speed, walking without an assistive device, and moderate physical activity.

RESULTS

In representative elderly populations, reducing sarcopenia severity by improving gait speed by 0.1 m/s in those with gait speed under 0.8 m/s generated a cumulative benefit of $65B by 2040 (2015 dollars). Improving walking ability in those with walking difficulty generated cumulative social benefit of $787B by 2040.

CONCLUSIONS

Reducing sarcopenia severity would generate significant health and economic benefits to society-almost $800B in the most optimistic scenarios.

Iron Homeostasis Controls Myeloid Blood Cell Differentiation in Drosophila

Iron is an essential divalent ion for aerobic life. Life has evolved to maintain iron homeostasis for normal cellular and physiological functions and therefore imbalances in iron levels exert a wide range of consequences. Responses to iron dysregulation in blood development, however, remain elusive. Here, we found that iron homeostasis is critical for differentiation of Drosophila blood cells in the larval hematopoietic organ, called the lymph gland. Supplementation of an iron chelator, bathophenanthroline disulfate (BPS) results in an excessive differentiation of the crystal cell in the lymph gland. This phenotype is recapitulated by loss of Fer1HCH in the intestine, indicating that reduced levels of systemic iron enhances crystal cell differentiation. Detailed analysis of Fer1HCH-tagged-GFP revealed that Fer1HCH is also expressed in the hematopoietic systems. Lastly, blocking Fer1HCH expression in the mature blood cells showed marked increase in the blood differentiation of both crystal cells and plasmatocytes. Thus, our work suggests a relevance of systemic and local iron homeostasis in blood differentiation, prompting further investigation of molecular mechanisms underlying iron regulation and cell fate determination in the hematopoietic system.

Graf regulates hematopoiesis through GEEC endocytosis of EGFR

GTPase regulator associated with focal adhesion kinase 1 (GRAF1) is an essential component of the GPI-enriched endocytic compartment (GEEC) endocytosis pathway. Mutations in the human GRAF1 gene are associated with acute myeloid leukemia, but its normal role in myeloid cell development remains unclear. We show that Graf, the Drosophila ortholog of GRAF1, is expressed and specifically localizes to GEEC endocytic membranes in macrophage-like plasmatocytes. We also find that loss of Graf impairs GEEC endocytosis, enhances EGFR signaling and induces a plasmatocyte overproliferation phenotype that requires the EGFR signaling cascade. Mechanistically, Graf-dependent GEEC endocytosis serves as a major route for EGFR internalization at high, but not low, doses of the predominant Drosophila EGFR ligand Spitz (Spi), and is indispensable for efficient EGFR degradation and signal attenuation. Finally, Graf interacts directly with EGFR in a receptor ubiquitylation-dependent manner, suggesting a mechanism by which Graf promotes GEEC endocytosis of EGFR at high Spi. Based on our findings, we propose a model in which Graf functions to downregulate EGFR signaling by facilitating Spi-induced receptor internalization through GEEC endocytosis, thereby restraining plasmatocyte proliferation.

Interleukin33 deficiency causes tau abnormality and neurodegeneration with Alzheimer-like symptoms in aged mice

This corrects the article DOI: 10.1038/tp.2017.142.