A pilot study investigating severe community-acquired febrile illness through implementation of an innovative microbiological and nucleic acid amplification testing strategy in Timor-Leste (ISIN-MANAS-TL)

Objectives

Acute febrile illness (AFI) causes significant health-seeking, morbidity, and mortality in Southeast Asia. This pilot study aimed to describe presentation, etiology, treatment, and outcomes of patients with AFI at one hospital in Timor-Leste and assessing the feasibility of conducting larger studies in this setting.

Methods

Patients attending Hospital Nacional Guido Valadares with tympanic or axillary temperature ≥37.5°C in whom a blood culture was taken as part of routine clinical care were eligible. Participants were followed up daily for 10 days and again after 30 days. Whole blood was analyzed using a real-time quantitative polymerase chain reaction assay detecting dengue virus serotypes 1-4 and other arthropod-borne infections.

Results

A total of 82 participants were recruited. Polymerase chain reaction testing was positive for dengue in 14 of 82 (17.1%) participants and blood culture identified a bacterial pathogen in three of 82 (3.7%) participants. Follow-up was completed by 75 of 82 (91.5%) participants. High rates of hospital admission (58 of 82, 70.7%), broad-spectrum antimicrobial treatment (34 of 82, 41.5%), and mortality (9 of 82, 11.0%) were observed.

Conclusions

Patients with AFI experience poor clinical outcomes. Prospective observational and interventional studies assessing interventions, such as enhanced diagnostic testing, clinical decision support tools, or antimicrobial stewardship interventions, are required and would be feasible to conduct in this setting.

Evolutionary immunology to explore original antiviral strategies

Over the past 25 years, the field of evolutionary developmental biology (evo-devo) has used genomics and genetics to gain insight on the developmental mechanisms underlying the evolution of morphological diversity of animals. Evo-devo exploits the key insight that conserved toolkits of development (e.g. Hox genes) are used in animals to produce genetic novelties that provide adaptation to a new environment. Like development, immunity is forged by interactions with the environment, namely the microbial world. Yet, when it comes to the study of immune defence mechanisms in invertebrates, interest primarily focuses on evolutionarily conserved molecules also present in humans. Here, focusing on antiviral immunity, we argue that immune genes not conserved in humans represent an unexplored resource for the discovery of new antiviral strategies. We review recent findings on the cGAS-STING pathway and explain how cyclic dinucleotides produced by cGAS-like receptors may be used to investigate the portfolio of antiviral genes in a broad range of species. This will set the stage for evo-immuno approaches, exploiting the investment in antiviral defences made by metazoans over hundreds of millions of years of evolution. This article is part of the theme issue 'Sculpting the microbiome: how host factors determine and respond to microbial colonization'.

"Nothing without connection"-Participant perspectives and experiences of mentorship in capacity building in Timor-Leste

The literature on mentorship approaches to capacity building in global health is limited. Likewise, there are few qualitative studies that describe mentorship in capacity building in global health from the perspective of the mentors and mentees. This qualitative study examined the perspectives and experiences of participants involved in a program of health capacity building in Timor-Leste that was based on a side-by-side, in-country mentorship approach. Semi-structured interviews were conducted with 23 participants (including Timorese and expatriate mentors, and local Timorese colleagues) from across a range of professional health disciplines, followed by a series of member checking workshops. Findings were reviewed using inductive thematic analysis. Participants were included in review and refinement of themes. Four major themes were identified: the importance of trust and connection within the mentoring relationship; the side-by-side nature of the relationship (akompaña); mentoring in the context of external environmental challenges; and the need for the mentoring relationship to be dynamic and evolving, and aligned to a shared vision and goals. The importance of accompaniment (akompaña) as a key element of the mentoring relationship requires further exploration and study. Many activities in global health capacity building remain focused on provision of training, supervision, and supportive supervision of competent task performance. Viewed through a decolonising lens, there is an imperative for global health actors to align with local priorities and goals, and work alongside individuals supporting them in their vision to become independent leaders of their professions. We propose that placing mentoring relationships at the centre of human resource capacity building programs encourages deep learning, and is more likely to lead to long term, meaningful and sustainable change.

National cross-sectional cluster survey of tuberculosis prevalence in Timor-Leste: a study protocol

INTRODUCTION

Timor-Leste has one of the world's highest estimated tuberculosis (TB) incidences, yet the data which informs this estimate is limited and the true burden of TB disease is not known. TB prevalence surveys offer the best means of determining robust estimates of disease burden. This study aims to provide an estimate of the prevalence of bacteriologically confirmed pulmonary TB in Timor-Leste and provide additional insights into diagnostic coverage and health-seeking behaviour of persons with symptoms suggestive of TB.

METHODS AND ANALYSIS

A national population-based cross-sectional cluster survey will be conducted in which participants aged 15 years and older will be screened for pulmonary TB using an algorithm consisting of symptom screening and digital X-ray of the chest with computer-aided detection software for X-ray interpretation. Xpert Ultra and liquid culture methods will be used to confirm survey TB cases. Additional data will be collected from persons reporting symptoms suggestive of TB to assess health-seeking behaviour and access to TB diagnosis and care. The survey aims to screen a target sample population of 20 068 people, living within 50 clusters, representing every municipality of Timor-Leste. Bacteriologically confirmed pulmonary TB prevalence will be estimated using WHO-recommended methods.

ETHICS AND DISSEMINATION

Research ethics approval has been granted by the human research ethics committee of the Northern Territory, Australia, and the Instituto Nacional da Saúde, Timor-Leste. The results will be published in a peer-reviewed scientific journal and disseminated with relevant stakeholders.

TRIAL REGISTRATION NUMBER

ACTRN12623000718640.

Investigating the Evolution of Drosophila STING-Dependent Antiviral Innate Immunity by Multispecies Comparison of 2'3'-cGAMP Responses

Viruses represent a major threat to all animals, which defend themselves through induction of a large set of virus-stimulated genes that collectively control the infection. In vertebrates, these genes include interferons that play a critical role in the amplification of the response to infection. Virus- and interferon-stimulated genes include restriction factors targeting the different steps of the viral replication cycle, in addition to molecules associated with inflammation and adaptive immunity. Predictably, antiviral genes evolve dynamically in response to viral pressure. As a result, each animal has a unique arsenal of antiviral genes. Here, we exploit the capacity to experimentally activate the evolutionarily conserved stimulator of IFN genes (STING) signaling pathway by injection of the cyclic dinucleotide 2'3'-cyclic guanosine monophosphate-adenosine monophosphate into flies to define the repertoire of STING-regulated genes in 10 Drosophila species, spanning 40 million years of evolution. Our data reveal a set of conserved STING-regulated factors, including STING itself, a cGAS-like-receptor, the restriction factor pastel, and the antiviral protein Vago, but also 2 key components of the antiviral RNA interference pathway, Dicer-2, and Argonaute2. In addition, we identify unknown species- or lineage-specific genes that have not been previously associated with resistance to viruses. Our data provide insight into the core antiviral response in Drosophila flies and pave the way for the characterization of previously unknown antiviral effectors.

The response to COVID-19 in Timor-Leste: lessons learnt

The response to the COVID-19 pandemic in Timor-Leste offers lessons that may be useful for incorporating into future responses to infectious disease outbreaks in similar resource-limited settings. In this paper, we identify nine key areas for learning from Timor-Leste's experience of the COVID-19 pandemic: (1) the importance of prior preparation for health emergencies, (2) the establishment of effective leadership and governance structures, (3) the protective impact of early border restrictions, (4) the rapid expansion of diagnostic laboratory capacity, (5) the impact of effective health communications in supporting the vaccine roll-out, (6) the opportunity to build capacity for clinical care, (7) the use of public health interventions that were found to have limited public health impact, (8) the broader effects of the pandemic and the public health response and (9) translation of lessons from COVID-19 to other public health priorities.

The virus-induced cyclic dinucleotide 2'3'-c-di-GMP mediates STING-dependent antiviral immunity in Drosophila

In mammals, the enzyme cGAS senses the presence of cytosolic DNA and synthesizes the cyclic dinucleotide (CDN) 2'3'-cGAMP, which triggers STING-dependent immunity. In Drosophila melanogaster, two cGAS-like receptors (cGLRs) produce 3'2'-cGAMP and 2'3'-cGAMP to activate STING. We explored CDN-mediated immunity in 14 Drosophila species covering 50 million years of evolution and found that 2'3'-cGAMP and 3'2'-cGAMP failed to control infection by Drosophila C virus in D. serrata and two other species. We discovered diverse CDNs produced in a cGLR-dependent manner in response to viral infection in D. melanogaster, including 2'3'-c-di-GMP. This CDN was a more potent STING agonist than cGAMP in D. melanogaster and it also activated a strong antiviral transcriptional response in D. serrata. Our results shed light on the evolution of cGLRs in flies and provide a basis for understanding the function and regulation of this emerging family of pattern recognition receptors in animal innate immunity.

Combined loss of CDH1 and downstream regulatory sequences drive early-onset diffuse gastric cancer and increase penetrance of hereditary diffuse gastric cancer

BACKGROUND

Germline CDH1 pathogenic or likely pathogenic variants cause hereditary diffuse gastric cancer (HDGC). Once a genetic cause is identified, stomachs' and breasts' surveillance and/or prophylactic surgery is offered to asymptomatic CDH1 carriers, which is life-saving. Herein, we characterized an inherited mechanism responsible for extremely early-onset gastric cancer and atypical HDGC high penetrance.

METHODS

Whole-exome sequencing (WES) re-analysis was performed in an unsolved HDGC family. Accessible chromatin and CDH1 promoter interactors were evaluated in normal stomach by ATAC-seq and 4C-seq, and functional analysis was performed using CRISPR-Cas9, RNA-seq and pathway analysis.

RESULTS

We identified a germline heterozygous 23 Kb CDH1-TANGO6 deletion in a family with eight diffuse gastric cancers, six before age 30. Atypical HDGC high penetrance and young cancer-onset argued towards a role for the deleted region downstream of CDH1, which we proved to present accessible chromatin, and CDH1 promoter interactors in normal stomach. CRISPR-Cas9 edited cells mimicking the CDH1-TANGO6 deletion display the strongest CDH1 mRNA downregulation, more impacted adhesion-associated, type-I interferon immune-associated and oncogenic signalling pathways, compared to wild-type or CDH1-deleted cells. This finding solved an 18-year family odyssey and engaged carrier family members in a cancer prevention pathway of care.

CONCLUSION

In this work, we demonstrated that regulatory elements lying down-stream of CDH1 are part of a chromatin network that control CDH1 expression and influence cell transcriptome and associated signalling pathways, likely explaining high disease penetrance and very young cancer-onset. This study highlights the importance of incorporating scientific-technological updates and clinical guidelines in routine diagnosis, given their impact in timely genetic diagnosis and disease prevention.

Vaccine Preventable Disease Seroprevalence in a Nationwide Assessment of Timor-Leste (VASINA-TL): study protocol for a population-representative cross-sectional serosurvey

INTRODUCTION

Historic disruption in health infrastructure combined with data from a recent vaccine coverage survey suggests there are likely significant immunity gaps to vaccine preventable diseases and high risk of outbreaks in Timor-Leste. Community-based serological surveillance is an important tool to augment understanding of population-level immunity achieved through vaccine coverage and/or derived from prior infection.

METHODS AND ANALYSIS

This national population-representative serosurvey will take a three-stage cluster sample and aims to include 5600 individuals above 1 year of age. Serum samples will be collected by phlebotomy and analysed for measles IgG, rubella IgG, SARS-CoV-2 antispike protein IgG, hepatitis B surface antibody and hepatitis B core antigen using commercially available chemiluminescent immunoassays or ELISA. In addition to crude prevalence estimates and to account for differences in Timor-Leste's age structure, stratified age-standardised prevalence estimates will be calculated, using Asia in 2013 as the standard population. Additionally, this survey will derive a national asset of serum and dried blood spot samples which can be used for further investigation of infectious disease seroepidemiology and/or validation of existing and novel serological assays for infectious diseases.

ETHICS AND DISSEMINATION

Ethical approval has been obtained from the Research Ethics and Technical Committee of the Instituto Nacional da Saúde, Timor-Leste and the Human Research Ethics Committee of the Northern Territory Department of Health and Menzies School of Health Research, Australia. Co-designing this study with Timor-Leste's Ministry-of-Health and other relevant partner organisations will allow immediate translation of findings into public health policy, which may include changes to routine immunisation service delivery and/or plans for supplementary immunisation activities.

A novel virus-induced cyclic dinucleotide, 2'3'-c-di-GMP, mediates STING-dependent antiviral immunity in Drosophila

In mammals, the enzyme cGAS senses the presence of cytosolic DNA and synthesizes the cyclic dinucleotide (CDN) 2'3'-cGAMP. This CDN binds to and activates the protein STING to trigger immunity. We recently discovered in the model organism Drosophila melanogaster two cGAS-like receptors (cGLRs) that activate STING-dependent antiviral immunity and can produce 3'2'-cGAMP, in addition to 2'3'-cGAMP. Here we explore CDN-mediated immunity in 14 different Drosophila species covering 50 million years of evolution and report that 2'3'-cGAMP and 3'2'-cGAMP fail to control infection by Drosophila C virus in D. serrata, D. sechellia and D. mojavensis . Using an accurate and sensitive mass spectrometry method, we discover an unexpected diversity of CDNs produced in a cGLR-dependent manner in response to viral infection in D. melanogaster , including a novel CDN, 2'3'-c-di-GMP. We show that 2'3'-c-di-GMP is the most potent STING agonist identified so far in D. melanogaster and that this molecule also activates a strong antiviral transcriptional response in D. serrata . Our results shed light on the evolution of cGLRs in flies and provide a basis for the understanding of the function and regulation of this emerging family of PRRs in animal innate immunity.

The epidemiology of the COVID-19 pandemic in the small, low-resource country of Timor-Leste, January 2020 - June 2022

Abstract

Timor-Leste, a small, mountainous half-island nation which shares a land border with Indonesia and which is 550 km from Australia, has a population of 1.3 million and achieved independence for the second time in 2002. It is one of the poorest nations in Asia. In response to the global coronavirus disease 2019 (COVID-19) pandemic, the Timor-Leste Ministry of Health undertook surveillance and contact tracing activities on all notified COVID-19 cases. Between 1 January 2020 and 30 June 2022, there were 22,957 cases of COVID-19 notified which occurred in three waves, the first which was delayed until April 2021 (community transmission of B.1.466.2 variant following major flooding), followed by waves in August 2021 (B.1.617.2 Delta variant transmission) and February 2022 (B.1.1.529 Omicron variant transmission). There were 753 people hospitalised due to COVID-19 and 133 deaths. Of the 133 deaths, 122 (92%) were considered not fully vaccinated (< 2 COVID-19 vaccines) and none had received boosters. Timor-Leste implemented measures to control COVID-19, including: rapid closure of international borders; isolation of cases; quarantining of international arrivals and close contacts; restrictions on internal travel; social and physical distancing; and, finally, a country-wide vaccination program. The health system's capacity was never exceeded.

Strengthening Health Research and Ethics Systems in Timor-Leste

Introduction

Meaningful health research should lead to evidence-based decision-making that can be translated into policy and practice. Every country needs to have a well-functioning and resourced ethics review and clearance system to ensure health and medical research is conducted in line with ethical standards, preventing harm to research participants, and contributing to better health outcomes and national priorities. The purpose of this study is to describe the origins of the system for managing health research and ethics in Timor-Leste and how it has evolved over time; to identify the strengths and limitations of the current system; and to recommend areas for improvement.

Materials and Methods

A narrative review of the literature (published papers, gray literature, and unpublished data) was conducted alongside key informant interviews with 15 Ministry of Health (MOH) policymakers and National Institute of Health staff between October 2020 and March 2021.

Results

The system for managing health research and ethics in Timor-Leste has remained largely the same since it was first established in 2009, with some adaptations to cope with a progressively increasing workload. Main findings include: the Department of Research and Studies (DRS) oversees complex ethics approval process in addition to other responsibilities; the DRS lacks the legal authority, policies, and procedures to help implement its full range of functions and responsibilities; national research priorities should be identified; MOH experiences difficulties in securing funding to support health research; training in health research, ethics and governance is an important priority for DRS.

Conclusion

It is timely and important to invest in strengthening key components of health research and ethics systems in Timor-Leste. Despite limited resources, improvements can be achieved in key areas with focused assistance and collaboration with local, national, and international partners.

Decarbonizing the energy supply one pandemic at a time

This study explores different energy consumption vectors during the first year of the COVID-19 pandemic in Portugal. Most of the workforce started working from home and resource consumption significantly shifted towards the domestic sector. The ensuing confinement protocols caused a shift in everyday life, which in turn significantly altered the energy supply and demand landscape. This event, although catastrophic in terms of loss of human life and economic development, can provide us with valuable data to study the potential of new strategies to achieve EU 2050 Energy goals. It was investigated whether the pandemic has opened a path and provided us with a partial answer to decarbonization in the form of home office practices as a possible energy efficiency measure. The present study shows that, in Portugal, there was a 15.7% reduction of primary energy consumption (accounting for electricity, natural gas and transport fuels) compared to 2019. The data suggest that actions targeting reduced mobility, such as home office practices and the decentralization of the workforce, could be a relevant energy efficiency measure.

Wolbachia-Conferred Antiviral Protection Is Determined by Developmental Temperature

Wolbachia is a maternally transmitted bacterium that is widespread in arthropods and filarial nematodes and confers strong antiviral protection in Drosophila melanogaster and other arthropods. Wolbachia-transinfected Aedes aegypti mosquitoes are currently being deployed to fight transmission of dengue and Zika viruses. However, the mechanism of antiviral protection and the factors influencing are still not fully understood. Here, we show that temperature modulates Wolbachia-conferred protection in Drosophila melanogaster. Temperature after infection directly impacts Drosophila C virus (DCV) replication and modulates Wolbachia protection. At higher temperatures, viruses proliferate more and are more lethal, while Wolbachia confers lower protection. Strikingly, host developmental temperature is a determinant of Wolbachia-conferred antiviral protection. While there is strong protection when flies develop from egg to adult at 25°C, the protection is highly reduced or abolished when flies develop at 18°C. However, Wolbachia-induced changes during development are not sufficient to limit virus-induced mortality, as Wolbachia is still required to be present in adults at the time of infection. This developmental effect is general, since it was present in different host genotypes, Wolbachia variants, and upon infection with different viruses. Overall, we show that Wolbachia-conferred antiviral protection is temperature dependent, being present or absent depending on the environmental conditions. This interaction likely impacts Wolbachia-host interactions in nature and, as a result, frequencies of host and symbionts in different climates. Dependence of Wolbachia-mediated pathogen blocking on developmental temperature could be used to dissect the mechanistic bases of protection and influence the deployment of Wolbachia to prevent transmission of arboviruses. IMPORTANCE Insects are often infected with beneficial intracellular bacteria. The bacterium Wolbachia is extremely common in insects and can protect them from pathogenic viruses. This effect is being used to prevent transmission of dengue and Zika viruses by Wolbachia-infected mosquitoes. To understand the biology of insects in the wild, we need to discover which factors affect Wolbachia-conferred antiviral protection. Here, we show that the temperature at which insects develop from eggs to adults can determine the presence or absence of antiviral protection. The environment, therefore, strongly influences this insect-bacterium interaction. Our work may help to provide insights into the mechanism of viral blocking by Wolbachia, deepen our understanding of the geographical distribution of host and symbiont, and incentivize further research on the temperature dependence of Wolbachia-conferred protection for control of mosquito-borne disease.

Blood ketone measurement as a test for dietary compliance in cardiac sarcoid patients undergoing 18f-fluorodeoxyglucose positron emission tomography

Funding Acknowledgements

Type of funding sources: None.

Background

Imaging with 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) is used as part of diagnosis and monitoring response to therapy in patients with cardiac sarcoidosis. In order to supress myocardial uptake of 18F-FDG patients prepare with a low carbohydrate diet followed by an 18-hour overnight fast. Failure to comply with the protocol results in diffuse myocardial 18F-FDG uptake which confounds diagnostic interpretation.

Purpose

To assess if point of care blood ketones could be used as a marker of dietary compliance and association with suppression of myocardial 18F-FDG uptake on PET scan.

Method

Patients (n = 26, 57 ± 4 years, 65% Male) from a single centre were instructed to follow standard preparation protocol prior to 18F-FDG PET/CT. After confirmation of dietary compliance, blood glucose and blood ketones were recorded using point of care devices. Images were graded based on the pattern of myocardial 18F-FDG uptake.

Results

There was no clear correlation between blood ketones in relation to dietary compliance or myocardial 18F-fluorodeoxyglucose uptake. In those with myocardial 18F-FDG uptake maximum standardized uptake value (SUV max) within the myocardium ranged from 2.3 to 9.8 (Mean 5.3) and ketone from 0.1 – 0.7 (normal &lt;0.6).

Non-diabetic patients and those on steroids achieved adequate fasting glucose without significant rise in blood ketones. 60% of diabetic patients demonstrated mildly elevated ketones between 0.6-1.5mmol/L.

Conclusion

Current protocol with low carbohydrate diet and 18-hour fast achieves adequate quality of images in majority of patients, without significant change in blood ketones. Therefore, blood ketones cannot be used to confirm dietary compliance.  Diabetic patients on insulin may benefit from ketone measurement due to risk of diabetic ketoacidosis.

The role of interventional bronchoscopy in the management of post-intubation tracheal stenosis: A 20-year experience

PURPOSE

Benign tracheal stenosis management is still controversial, and there is no international consensus on the best treatment option. Thus, we aimed to look into the history of PITS and the different strategies used in its treatment. The importance of bronchoscopic treatment was also defined, and its effectiveness and safety were assessed.

METHODS

Retrospective study of patients diagnosed with PITS, who were referred to the Bronchology Department between January 1996 and December 2016.

RESULTS

Of 115 patients enrolled (mean age 48.5±17.6 years, 53% males), 66.1% had complex stenosis. The most common causes of intubation were respiratory (29.9%), neurological (26.8%) and surgical (19.6%). Complex stenosis was caused by longer intubation, and was more frequent among previously tracheostomized patients. The most common location was the upper third of trachea (60.9%). Most cases were initially treated by interventional bronchoscopy, and although serial dilations were effective in some complex PITS, a higher proportion of simple stenosis was successfully managed with this treatment option. Long-term recurrence after serial dilation was observed in 25.0% of cases. Stent placement was required (19.1%) only for complex PITS. Stent-related complications were frequent (61.9%) and linked to the stenting time (p<0.001). Overall, there were no procedure-related complications. Surgical intervention was also performed (30.0%), always with complex PITS. Post-surgical recurrences were observed in 24.2% of cases.

CONCLUSIONS

Interventional bronchoscopy is an efficient and safe modality in PITS management. Further studies are needed for better classification and improved knowledge of PITS pathogenesis, and to achieve international consensus of definition to guide clinicians in their practice.

The effect of a novel Bayesian penalised likelihood PET reconstruction algorithm on the assessment of malignancy risk in solitary pulmonary nodules according to the British Thoracic Society guidelines

PURPOSE

British Thoracic Society (BTS) guidelines advocate using FDG PET-CT with the Herder model to estimate malignancy risk in solitary pulmonary nodules (SPNs). Qualitative and semi-quantitative assessment of SPN uptake is based upon analysis of Ordered Subset Expected Maximisation (OSEM) PET images. Our aim was to assess the effect of a Bayesian Penalised Likelihood (BPL) PET reconstruction on the assessment of SPN FDG uptake and estimation of malignancy risk (Herder score).

METHODS

Subjects with SPNs who underwent FDG PET-CT between 2014-2017, with histological confirmation of malignancy or histological/imaging follow-up confirmation of benignity were included. Two blinded readers independently classified SPN uptake on both OSEM and BPL (BTS score; 1 = none; 2 = ≤ mediastinal blood pool (MBP); 3 = >MBP but ≤ 2x liver; 4 = >2x liver), with resultant calculation of the Herder score (%) for both reconstructions.

RESULTS

97 subjects with 75 (77%) malignant SPNs were included. BPL increased the BTS score in 25 (26%) SPNs; 9 SPNs (7 malignant) increased from BTS score 2 to 3, 16 (13 malignant) from BTS score 3 to 4, with a mean Herder score increase of 18 ± 22%. The mean Herder score for all SPNs with BPL was higher than OSEM (73 ± 29 vs 68 ± 32%, p = 0.001). There was no difference in Herder model diagnostic performance between BPL and OSEM, with similar areas under the curve (0.84 vs 0.83, p = 0.39).

CONCLUSION

BPL increases the Herder score in 26% of SPNs compared to OSEM but does not alter the diagnostic performance of the Herder model.

Upper Airway Video Endoscopy: Assessment of the response to positive pressure ventilation and mechanical in-exsufflation

Upper airways (UA) include the nasal cavities, pharynx, and larynx, and its main function is to warm and filter the inspired air. UA dysfunction is in the pathogenesis of various disorders, such as obstructive sleep apnea syndrome (OSAS) and vocal cord dysfunction. In addition, in some neurodegenerative diseases (e.g. Amyotrophic Lateral Sclerosis - ALS), UA dysfunction may also compromise the effective use of ventilatory support (VS). In this context, the endoscopic evaluation of UA may be useful in understanding the OSAS mechanisms, in determining the causes for treatment-induced airway obstruction and even in helping to titrate noninvasive ventilation (NIV) in ALS patients with bulbar or pseudo-bulbar (spastic) dysfunction. Specifically, in OSAS patients, when residual obstructive events persist, although an optimal ventilatory mode has been apparently achieved, along with interface and equipment, the endoscopic evaluation of UA seems to be a valuable tool in understanding its mechanisms, even assisting adjustments to NIV parameters. In addition, it has also been described as being useful in laryngeal response to mechanical in-exsufflation (MI-E) and Exercise-Induced Laryngeal Obstruction (EILO). However, no protocol has yet been published or validated for this. For this reason, a literature review was conducted on UA function and its response to positive pressure and MI-E. Special emphasis has also been given to the current indication for video endoscopy in chronically ventilated patients.

Fully Automatic Finger Extensor Tendon Segmentation in Ultrasound Images of the Metacarpophalangeal Joint

In this work a fully automatic system to identify the extensor tendon on ultrasound images of the metacarpophalangeal joint is proposed. These images are used to diagnose rheumatic diseases which are one of the main causes of impairment and pain in developed countries. The early diagnosis of these conditions is crucial to a proper treatment and follow-up and so, a system such as the one proposed here, could be useful to automatically extract relevant information from the resulting images. This work is an extension of a previous published work which uses manual annotations of the skin line, metacarpus and phalange to guide the extensor tendon segmentation. By introducing automatic segmentations of all structures, we expect to create a fully automatic system, which is more interesting to the possible end-users. Results show that, despite an expected loss in the performance, it is still possible to correctly identify the extensor tendon with a Confidence of 88% considering a maximum allowed Modified Hausdorff Distance of 0.5mm.

Extracting Thickness Profiles of Anterior Mitral Leaflets in Echocardiography Videos

Rheumatic heart disease is the serious consequence of repeated episodes of acute rheumatic fever. It is the major cause of heart valve damage resulting in morbidity and mortality. Its early detection is considered vital to control the disease's progression. The key manifestations that are visible in the early stages of this disease are changes in the thickness, shape and mobility of the mitral valve leaflets. Echocardiography based screening is sensitive enough to identify these changes in early stages of the disease. In this work, an automatic approach is proposed to measure, quantify and analyze the thickness of the anterior mitral leaflet, in an echocardiographic video. The shape of the anterior mitral leaflet is simplified via morphological skeletonization and spline modelling to get the central line of the leaflet. To analyze the overall thickness from the tip to its base, the anterior mitral leaflet is divided into four quartiles. In ach quartile the thickness is measured as the length of the line segment resulting from the intersection of the contour with the normal direction of the central point of each quartile. Finally, the thickness is analyzed by measuring the variance per quartile, divided by leaflet position (open, straight and closed). The comparison between the normal and pathological leaflets are also presented, exhibiting statistical significant differences in all quartiles, especially near the tip of the leaflet.

A New Method for the Anterior Mitral Leaflet Segmentation in Echocardiography Videos using the Virtual M-mode Space

Rheumatic heart disease is responsible for the heart valve damage, caused by repeated episodes of rheumatic fever. The disease commonly inflames and scars the mitral valve of the heart, resulting in thicker, less mobile leaflets, with associated decrease in cardiac efficiency. It is important to measure and quantity the early manifestations of this disease, including variations of the thickness, shape and mobility of the leaflets. These manifestations are visible in an echocardiographic screening process. The first step towards the defined objective is to segment the anterior mitral leaflet throughout the cardiac cycle, enabling the future automatic quantification of mentioned clinical parameters. In this work, a new algorithm for the segmentation of the whole region of the anterior mitral leaflet in the virtual M-mode space is proposed. The algorithm requires a single initialization point on the posterior wall of the aorta, in the first frame of the video. A junction point is then computed, showing the location where the two leaflets connect. This junction point helps to automatically redefine the range of virtual M-mode images required to completely segment the region of the anterior mitral leaflet. The segmented anterior mitral leaflet region in the virtual M-mode space is transferred back to regular image space and its shape refined using localized active contours. Results suggest the suitability of the proposed algorithm for the segmentation of anterior mitral leaflet with a median Dice Similarity Coefficient of 0.63, and with median precision and recall of 58% and 73% respectively.

The Kinase IKKβ Regulates a STING- and NF-κB-Dependent Antiviral Response Pathway in Drosophila

Antiviral immunity in Drosophila involves RNA interference and poorly characterized inducible responses. Here, we showed that two components of the IMD pathway, the kinase dIKKβ and the transcription factor Relish, were required to control infection by two picorna-like viruses. We identified a set of genes induced by viral infection and regulated by dIKKβ and Relish, which included an ortholog of STING. We showed that dSTING participated in the control of infection by picorna-like viruses, acting upstream of dIKKβ to regulate expression of Nazo, an antiviral factor. Our data reveal an antiviral function for STING in an animal model devoid of interferons and suggest an evolutionarily ancient role for this molecule in antiviral immunity.

Quorum-sensing regulator RhlR but not its autoinducer RhlI enables Pseudomonas to evade opsonization

When Drosophila melanogaster feeds on Pseudomonas aeruginosa, some bacteria cross the intestinal barrier and eventually proliferate in the hemocoel. This process is limited by hemocytes through phagocytosis. P. aeruginosa requires the quorum-sensing regulator RhlR to elude the cellular immune response of the fly. RhlI synthesizes the autoinducer signal that activates RhlR. Here, we show that rhlI mutants are unexpectedly more virulent than rhlR mutants, both in fly and in nematode intestinal infection models, suggesting that RhlR has RhlI-independent functions. We also report that RhlR protects P. aeruginosa from opsonization mediated by the Drosophila thioester-containing protein 4 (Tep4). RhlR mutant bacteria show higher levels of Tep4-mediated opsonization, as compared to rhlI mutants, which prevents lethal bacteremia in the Drosophila hemocoel. In contrast, in a septic model of infection, in which bacteria are introduced directly into the hemocoel, Tep4 mutant flies are more resistant to wild-type P. aeruginosa, but not to the rhlR mutant. Thus, depending on the infection route, the Tep4 opsonin can either be protective or detrimental to host defense.

Tracking large Anterior Mitral Leaflet displacements by incorporating optical flow in an active contours framework

Echocardiography is an important tool to detect early evidence of mitral valve degradation associated with rheumatic heart disease. The segmentation and tracking of the Anterior Mitral Leaflet helps to quantify the morphologic valve anomalies, such as the leaflet thickening, shape and the mobility changes. The tracking of this leaflet throughout the cardiac cycle is still an open challenge in the research community. The widely used active contours segmentation framework fails when faced with large leaflet displacement. In this work, we propose the integration of optical flow in an open-ended active contour framework to address this difficulty. This additional information promotes solutions with contours next to high leaflet displacements, resulting in superior performance. The algorithm was tested on 9 fully annotated real clinical videos, acquired from the parasternal long axis view. The algorithm is compared with our previous work. Results show a clear improvement in situations where the leaflet exhibits large displacement or irregular shapes, with an average error of 4.5 pixels and a standard deviation of 2 pixels.

A New Active Contours Approach for Finger Extensor Tendon Segmentation in Ultrasound Images Using Prior Knowledge and Phase Symmetry

This work proposes a new approach for the segmentation of the extensor tendon in ultrasound images of the second metacarpophalangeal joint (MCPJ). The MCPJ is known to be frequently involved in early stages of rheumatic diseases like rheumatoid arthritis. The early detection and follow up of these diseases is important to start and adapt the treatments properly and, in that way, preventing irreversible damage of the joints. This work relies on an active contours framework, preceded by a phase symmetry preprocessing and with prior knowledge energies, to automatically identify the extensor tendon. Active contours methods are widely used in ultrasound images because of their robustness to speckle noise and ability to join unconnected smaller regions into a coherent shape. The tendon is formulated as a line so open ended active contours were used. Phase symmetry highlights the tendon, by setting a proper scale range and angle span. The distance between structures and the tendon slope were also included to enforce the model based on anatomical characteristics. And finally, the concavity measures were used because, given the anatomy of the finger, we know that the tendon line should have less than two concavities. To solve the active contours energy minimization a genetic algorithm approach was used. Several energy metric configurations were compared using the modified Hausdorff distance and results showed that this segmentation is not only possible, but exhibits errors smaller than 0.5 mm with a confidence of 95% with the phase symmetry preprocessing and energies based on the line neighborhood, area ratio, slope, and concavity measurements.

Treatment of long anterior urethral stricture associated to lichen sclerosus

INTRODUCTION

Panurethral stricture associated with lichen sclerosus is a therapeutic challenge. We present the analysis of our results using two urethroplasty techniques based on oral mucosa graft.

MATERIAL AND METHOD

Retrospective study in patients with long anterior urethral stricture (>8cm) associated with lichen sclerosus. Patients received urethroplasty with oral mucosa graft technique according Kulkarni (n=25) or two-step Johanson-Bracka urethroplasty (n=15). Demographics, operative time, complications (Clavien-Dindo), hospital stay, days with catheter, EAV postoperative pain, failure rate, need for retreatment and functional data including IPSS, QoL, Qmax, post void residual (PVR) are evaluated.

RESULTS

In all cases there was involvement of glandular and penile urethra, and in 75% of bulbar urethra. A single graft was used in 22.5%, two in 72.5% and three in 5%. Patients treated at a single step were younger (P=.007). Although the length of the stenosis was equivalent in both techniques (P=.96), relapse and complication rates were higher in two-step surgery (P=.05 and P=.03; respectively) and so was operative time (P<.0001) and overall stay (P=.0002). There were no differences in preoperative IPSS, QoL, Qmax or PVR, neither in postoperative values of IPSS or Qmax; but there was a difference in QoL (P=.006) and PVR (P=.03) favouring single-step urethroplasty. VAS pain on postoperative day 1 was also lower in Kulkarni urethroplasty than in the first step of Johanson-Bracka technique (P<.0001).

CONCLUSIONS

In patients with lichen sclerosus and long anterior urethral stricture Kulkarni urethroplasty provides more efficient and better patient reported outcomes than Johanson-Bracka urethroplasty. It also prevents cosmetic, sexual and voiding temporary deterioration inherent to 2-step surgery.

Surgical capacity building in Timor-Leste: a review of the first 15 years of the Royal Australasian College of Surgeons-led Australian Aid programme

BACKGROUND

Timor-Leste suffered a destructive withdrawal by the Indonesian military in 1999, leaving only 20 Timorese-based doctors and no practising specialists for a population of 700 000 that has now grown to 1.2 million.

METHODS

This article assesses the outcomes and impact of Royal Australasian College of Surgeons (RACS) specialist medical support from 2001 to 2015. Three programmes were designed collaboratively with the Timor-Leste Ministry of Health and Australian Aid. The RACS team began to provide 24/7 resident surgical and anaesthesia services in the capital, Dili, from July 2001. The arrival of the Chinese and Cuban Medical Teams provided a medical workforce, and the Cubans initiated undergraduate medical training for about 1000 nationals both in Cuba and in Timor-Leste, whilst RACS focused on specialist medical training.

RESULTS

Australian Aid provided AUD$20 million through three continuous programmes over 15 years. In the first 10 years over 10 000 operations were performed. Initially only 10% of operations were done by trainees but this reached 77% by 2010. Twenty-one nurse anaesthetists were trained in-country, sufficient to cover the needs of each hospital. Seven Timorese doctors gained specialist qualifications (five surgery, one ophthalmology and one anaesthesia) from regional medical schools in Papua New Guinea, Fiji, Indonesia and Malaysia. They introduced local specialist and family medicine diploma programmes for the Cuban graduates.

CONCLUSIONS

Timor-Leste has developed increasing levels of surgical and anaesthetic self-sufficiency through multi-level collaboration between the Ministry of Health, Universidade Nacional de Timor Lorosa'e, and sustained, consistent support from external donors including Australian Aid, Cuba and RACS.

Discovery of novel targets for antivirals: learning from flies

Developing antiviral drugs is challenging due to the small number of targets in viruses, and the rapid evolution of viral genes. Animals have evolved a number of efficient antiviral defence mechanisms, which can serve as a source of inspiration for novel therapies. The genetically tractable insect Drosophila belongs to the most diverse group of animals. Genetic and transcriptomic analyses have recently identified Drosophila genes encoding viral restriction factors. Some of them represent evolutionary novelties and their characterization may provide hints for the design of directly acting antivirals. In addition, functional screens revealed conserved host factors required for efficient viral translation, such as the ribosomal protein RACK1 and the release factor Pelo. These proteins are promising candidates for host-targeted antivirals.

Segmentation of the metacarpus and phalange in musculoskeletal ultrasound images using local active contours

This work presents a method for the automatic segmentation of metacarpus and phalange bones in ultrasound images of the second metacarpophalangeal joint (MCPJ) using Active Contours. The MCPJ is known to be the one of the first structures to be affected by rheumatic diseases like rheumatoid arthritis. The early detection and follow-up of this disease is important to prevent irreversible damage of the joints, which occurs continuously and faster if no treatment is used. To our knowledge, there is no automatic system to quantify the extension of the lesions resulting from rheumatic activity. The objective of this work is to identify the metacarpus and the phalange bones using local active contours. To our knowledge, there is no well established method for this problem and this technique has not been used yet in these structures. Results proved that the automatic segmentation is possible with an error of 3 pixels for a confidence of 80%.

Tracking of the anterior mitral leaflet in echocardiographic sequences using active contours

Echocardiography assessment of cardiac valves plays a vital role in the diagnosis of rheumatic heart disease. In the vast majority of cases, the mitral valve gets affected, leading to the thickening of its leaflets that may result in the fusion of their tips. This changes the appearance and reduces the mobility of the leaflets, which also reduce the heart efficiency. Quantifying such parameters provides diagnostic insight. To achieve that, the first step is to identify and then track fast moving leaflets. This work is focused on Anterior Mitral Leaflet (AML) tracking. Open ended active contours are employed in this work by removing its boundary conditions. The external and internal energy of the contour is modified that extend the capture range, improve snake energy and encourages the leftmost end point of the contour to converge on the moving tip of the AML. Results show that contour points are tracked accurately with an average error of 4.9 pixels and a standard deviation of 2.1 pixels in 9 fully annotated normal sequences of real children clinical assessments.

The use of the color Doppler ultrasonography in the diagnosis and monitoring of an atypical case of giant-cell arteritis

Giant Cell Arteritis (GCA) is a large vessels vasculitis that is typically characterised by headache, scalp tenderness, jaw claudication and visual disturbances. Temporal arteries color Doppler ultrasonography (CDUS) is a sensitive and non-invasive image technique used in the diagnosis of this disease. This work highlights the importance of CDUS in the diagnostic workup of GCA and also demonstrates it´s usefullness in the evaluation and documentation of the response to corticosteroids therapy in an atypical case of ACG.