Specific Phylotypes of Saprolegnia parasitica Associated with Atlantic Salmon Freshwater Aquaculture

Saprolegniosis is a major destructive disease in freshwater aquaculture. The destructive economic impact of saprolegniosis on freshwater aquaculture necessitates further study on the range of Saprolegnia species within Atlantic salmon fish farms. This study undertook a thorough analysis of a total of 412 oomycete and fungal isolates that were successfully cultured and sequenced from 14 aquaculture sites in Scotland across a two-year sampling period. An ITS phylogenetic analysis of all isolates was performed according to whether they were isolated from fish or water samples and during enzootic or epizootic periods. Several genera of oomycetes were isolated from sampling sites, including Achlya, Leptolegnia, Phytophthora, and Pythium, but by far the most prevalent was Saprolegnia, accounting for 66% of all oomycetes isolated. An analysis of the ITS region of Saprolegnia parasitica showed five distinct phylotypes (S2-S6); S1 was not isolated from any site. Phylotype S2 was the most common and most widely distributed phylotype, being found at 12 of the 14 sampling sites. S2 was overwhelmingly sampled from fish (93.5%) and made up 91.1% of all S. parasitica phylotypes sampled during epizootics, as well as 67.2% of all Saprolegnia. This study indicates that a single phylotype may be responsible for Saprolegnia outbreaks in Atlantic salmon fish farms, and that water sampling and spore counts alone may be insufficient to predict Saprolegnia outbreaks in freshwater aquaculture.

Maternofetal outcomes in early-onset gestational diabetes: does weight gain matter?

AIM

Women with early-onset gestational diabetes mellitus (GDM) have overall lower gestational weight gain (GWG) compared to those with later-onset GDM, albeit with usually worse maternofetal outcomes. We intent to investigate the association between inadequate GWG and maternofetal outcomes in pregnant women with early-onset GDM.

METHODS

We performed a retrospective study of women with early-onset GDM based on the National Registry of GDM. Three study groups were defined according to the recommendations of the Institute of Medicine for GWG: excessive GWG (eGWG), adequate (aGWG) or insufficient (iGWG).

RESULTS

A total of 8040 pregnant women were included: 27% (n = 2170) eGWG, 31% (n = 2492) aGWG and 42% (n = 3378) iGWG. Preeclampsia (4.3 vs 3 vs 1.6%, p < 0.001), polyhydramnios (3.1 vs 2.3 vs 1.8%, p = 0.008) and cesarean section (37.4 vs 34.1 vs 29.5%, p < 0.001) were significantly more frequent among women with eGWG. Additionally, there was a higher frequency of macrosomia (8.1 vs 3.6 vs 2.4%, p < 0.001), large-for-gestational-age (8.2 vs 3.7 vs 2.6%, p < 0.001) and birth trauma (2.6 vs 1.5 vs 1.1%, p < 0.001) in this group. On the other hand, fetal death (0.2 vs 0.2 vs 0.5%, p = 0.04), small-for-gestational-age (9 vs 10.3 vs 14.9, p < 0.001) and preterm delivery (5.6 vs 7.1 vs 7.5%, p = 0.03) were more frequent in iGWG group.

CONCLUSIONS

Over two-thirds of pregnant women with early-onset GDM had inappropriate GWG, which was significantly associated with adverse maternofetal outcomes. Weight management must be a focus of special attention in women with early-onset GDM, beyond glycemic control, to achieve healthy pregnancy outcomes.

Multimodality imaging for the assessment of left ventricular dynsfunction in cardio-oncology

Funding Acknowledgements

Type of funding sources: None.

Introduction

Left ventricular systolic dysfunction (LVD) is a key concern in the context of cardio-oncology (CO). Usually, referral for suspected Cancer therapy-related cardiac dysfunction (CTRCD) is the main challenge, but heart failure with other more common causes, such as ischemic cardiomyopathy can also decompensate during cancer treatment or be diagnosed incidentally during cardiotoxicity echocardiographic (echo) surveillance. Multimodality imaging is essential in these patients in order to better establish aetiology and assure the most appropriate clinical management.

Purpose

evaluate clinical impact of multimodality imaging in the clinical management of CO patients.

Methods

retrospective study of a population followed in CO consultation. Statistical analysis of demographic, clinical, transthoracic echocardiography (TTE) and cardiac magnetic resonance (CMR) data was made.

Results

we included 115 pts, mean age 66.3 ± 10.2 years, 67,8% female, with mean follow-up of 16.1 ± 12.8 months. About half (56.5%) had breast cancer, followed by gastrointestinal tract (16.5%) and haematological (8,7%) malignancies, with a significant proportion (32,2%) with advanced disease. Prevalence of cardiovascular risk factors was high (hypertension in 74.8%, dyslipidaemia in 47%, type 2 diabetes mellitus in 17.4%), but also coronary artery disease (18,3%) and atrial fibrillation (18.3%). All of them were treated with different types of chemotherapy and 53,9% of pts with radiotherapy.  At baseline, 13% of pts had a left ventricular ejection fraction (LVEF) under 50% (LVD) assessed by TTE, which increased to 26,9% (n = 31) after oncological treatment initiation. Of these (n = 31), an ischemic aetiology was found in 32,3% and non-ischemic in 54,8%, which was significantly more frequent in patients with CTRCD (OR 2,7, p = 0,001). CMR was performed in 45,2%, mostly in CTRCD cases (p = 0,012, OR 8,4), which, apart from LVD, did not show any tissue changes in most patients (p = 0,026, OR 35). Only one patient with CTRCD (under treatment with trastuzumab and anthracyclines) had subepicardial late gadolinium enhancement, with wall motion abnormalities, suggesting a myocarditis-like mechanism for cardiotoxicity.

Conclusion

LVD has a major impact in patients" prognosis, particularly in CO context, where effective oncological treatments can be compromised due heart failure decompensation. Therefore, a thorough clinical evaluation should encompass etiological study in order to provide the most appropriate treatment strategies. Moreover, CTRCD can develop through different physiopathological mechanisms. Thus, multimodality imaging, particularly including CMR evaluation, can have a major role ensuring a good clinical outcome for these patients.

Adverse in-hospital prognosis in patients with non-ST-segment elevation myocardial infarction with right bundle branch block – red flag ECG and sicker patients

Introduction

Recent recommendations regarding myocardial infarction (MI) underline the adverse prognosis associated with right bundle branch block (RBBB), suggesting that, in some cases of non-ST-segment elevation MI (NSTEMI) with RBBB a primary percutaneous coronary intervention (PCI) strategy should be considered. However, it is unclear if this is due to a more difficult and late diagnosis or to the clinical severity inherent to these patients (pts).

Purposes

To characterize the NSTEMI with RBBB population and find predictors of worse prognosis.

Methods

Retrospective analysis of pts included in the Portuguese Registry of Acute Coronary Syndromes with NSTEMI, comparing pts with RBBB (group A) vs without RBBB (group B), regarding clinical and demographic variables, diagnostic and therapeutic approaches. Primary endpoint was heart failure, electrical and mechanical complications and death in the in-hospital period.

Results

We included 9375 pts, 686 in group A and 8689 in group B. Pts in group A were more likely to be male (p&lt;0.001) and over 75 years old (p&lt;0.001). Also, they were more prone to have cardiovascular risk factors (hypertension - p&lt;0.001, diabetes – p&lt;0.001) and history of coronary artery disease (stable angina p=0.007, previous MI p=0.002 and revascularization, either PCI – p=0.016 or surgery – p&lt;0.001), stroke (p&lt;0.001), chronic kidney disease (p&lt;0.001) and cancer (p=0.025), comparing to pts in group B. There were no differences between time from onset of symptoms and first medical contact or hospital admission between groups. Upon admission, these pts presented more frequently with hypotension (p=0.026), Killip class&gt;II (p&lt;0.001) and atrial fibrillation (p&lt;0.001) than pts in group B. There were statiscally significant differences between groups, regarding the use of inotropes (p&lt;0.001), non-invasive (p=0.008) and invasive ventilation (p=0.018) and temporary pacing (p=0.001), all of them higher in group A.

Pts with RBBB were less likely to undergo coronary angiography (CA) (p&lt;0.001). However, among those who did, there were no differences in CA timing (p=0.091), but pts from group A had more frequently multivessel disease (p=0.044) and no revascularization was undertaken (p=0.012).

About 16.64% of all pts reached the endpoint, but unfavourable in-hospital outcome was significantly more common in group A (p&lt;0.001). RBBB remained an independent predictor of the endpoint (p=0.032) in a multivariate regression analysis, controlled for other variables (namely gender, age, cardiovascular risk factors, previous evidence of cardiovascular disease, and clinical and coronary anatomy data) – AUC of 0.833.

Conclusion

Although pts with NSTEMI and RBBB have a poorer in-hospital prognosis, partly due to their bigger clinical complexity (older age, multiple comorbidities and complex coronary anatomy), RBBB itself still remains an independent predictor of worse outcome.

Funding Acknowledgement

Type of funding sources: None.

Mild periconceptional hyperglycemia: predictor of adverse fetomaternal outcomes in gestational diabetes?

AIM

To clarify whether mild first trimester hyperglycaemia (characteristic of early-onset GDM) is associated with higher incidence of congenital malformations and other adverse fetomaternal outcomes compared to women with second trimester hyperglycaemia (later-onset GDM).

DESIGN AND METHODS

We analyzed the Portuguese National GDM database, containing data collected between 2011 and 2017. Two study groups were defined: Group 1-Women with GDM diagnosed during the first trimester (with fasting glycemia ≥ 92 and < 126 mg/dL); Group 2-Women with GDM diagnosed after the first 12 weeks of gestation, with either fasting glycemia or oral glucose tolerance test, according to the International Association of Pregnancy and Diabetes Study Group criteria. The fetomaternal characteristics of each group were compared.

RESULTS

A total of 18.518 pregnant women diagnosed with GDM were included which 34.4% of them belonged to Group 1. Pregnant women from this group were significantly younger and had a higher median BMI than the women from the other group. Overall, there was no significant differences in maternal morbidity parameters between groups. Non-evolutive pregnancies were significantly more frequent along the present gestation in the group 1 (1.1% vs. 0.1%, p < 0.001), as was fetal death (0.6% vs. 0.2%, p < 0.001). Congenital malformations did not differ significantly between groups (3.2% vs. 2.8%, p = 0.155).

CONCLUSIONS

The mild near conceptional hyperglycaemic state characteristic of an early-onset GDM seems to be associated with an increased prevalence of non-evolutive pregnancies and foetal deaths when compared to later-onset GDM.

Evaluation of Potential Transfer of the Pathogen Saprolegnia parasitica between Farmed Salmonids and Wild Fish

Saprolegnia infections are among the main parasitic diseases affecting farmed salmonids. The distribution and potential transfer of Saprolegnia spp. between farms and the natural environment has been scarcely investigated. Therefore, this work aimed to study the diversity and abundance of oomycete species in salmonid farms, tributary water, and effluent water systems. Four trout farms in Italy and two Atlantic salmon farms in Scotland were considered. In Italian farms, 532 isolates of oomycetes were obtained from fish and water, at upstream, inside, and downstream the farms. In Scottish farms, 201 oomycetes isolates were obtained from water outside the farm and from fish and water inside the farming units. Isolates were identified to the species level through amplification and sequencing of the ITS rDNA region. In Italy, S. parasitica was significantly more present in farmed than in wild fish, while in water it was more frequently isolated from the wild, particularly in effluent systems, not associated with more frequent isolation of S. parasitica in wild fish downstream the farm. In Scotland, S. parasitica was the most prevalent species isolated from fish, while isolates from water were mostly Pythium spp. with few S. parasitica isolates from upstream and downstream the farms.

Development of a 3D spheroid cell culture system from fish cell lines for in vitro infection studies: Evaluation with Saprolegnia parasitica

Understanding the ways in which pathogens infect host cells is essential to improve and develop new treatment strategies. This study aimed to generate a novel in vitro infection model by establishing a reproducible 3D spheroid cell culture system that may lead to a reduced need for animals in fish disease research. 2D models (commonly cell lines) cannot replicate many key conditions of in vivo infections, but 3D spheroids have the potential to provide bridging technology between in vivo and in vitro systems. 3D spheroids were generated using cells from rainbow trout (Oncorhynchus mykiss) cell lines, RTG-2 and RTS-11. The RTG-2 spheroids were tested for their potential to be infected upon exposure to Saprolegnia parasitica spores. Positive infiltration of mycelia into the spheroids was verified by confocal microscopy. As a closer analogue of in vivo conditions encountered during infection, the straightforward model developed in this study shows promise as an additional tool that can be used to further our understanding of host-pathogen interactions for Saprolegnia and possibly a variety of other fish pathogens.

Impact of pre-treatment with acetylsalicylic acid on the severity of a first myocardial infarction in diabetic patients

Introduction

Diabetes Mellitus (DM) is one of the main risk factors for cardiovascular disease (CVD). Guidelines on the use of acetylsalicylic acid (ASA) for primary prevention of CVD in this population are conflicting. A potential reduction in the severity of a first episode of Acute Myocardial Infarction (AMI) could be seen has an additional argument for the use of ASA in primary prevention. Aim: To evaluate the impact of prior intake of ASA on the presentation, severity and short-term prognosis of AMI in diabetic patients without history of CVD.

Methods

Retrospective analysis of diabetic patients without previous evidence of CVD diagnosed with type 1 AMI between January 2002 and December 2018, inserted in a multicentric registry of acute coronary syndromes. Patients were dichotomized according to whether or not they were taking ASA prior to the index event. Groups were compared according to clinical, analytical and imaging endpoints.

Results

A total of 2596 patients were included, predominantly men (66.4%), with a mean age of 68±12 years old. Patients on ASA (19.7%) were significantly older (71±10 vs. 67±12, p&lt;0.001) and had a higher prevalence of hypertension (89.2% vs 77.9%, p&lt;0.001), dyslipidaemia (69.8% vs. 61.1%, p&lt;0.001) and chronic kidney disease (10.6% vs. 4.9%, p&lt;0.001). Overall, there was a lower prevalence of AMI with ST-segment elevation (36.5% vs. 50.8%, p&lt;0.001) in patients on ASA. However, the same group of patients had a significantly higher probability of evolution in Killip class &gt; I (25.4% vs. 17.0%, p&lt;0.001), a higher median BNP elevation (315 [126–623] vs. 166 [64–431], p&lt;0.001); and a lower average ejection fraction upon discharge (49.0±12 vs. 51±12, p=0.011). Patients on prior regular intake of ASA also had a higher prevalence of multivessel disease (38.4% vs. 28.9%, p&lt;0.001) and multiple significant stenosis (70.2% vs. 61.7%, p&lt;0.001). There was no significant difference regarding the percentage of electrical complications (2.3% vs. 1.2%, p=0.06), use of intra-aortic balloon pump (1.0 vs. 0.9%, p=0.74) and in-hospital death (3.0% vs. 2.4%, p=0.46). In a logistic regression model adjusted for age, sex, comorbidities and previous medication as variates, prior ASA intake was an independent predictor of a lower rate of AMI with ST-segment elevation (ExpB −0.34; 95% CI: 0.57–0.89; p=0.003). On the contrary, when adjusted to these variables, prior ASA intake was not an independent predictor of higher BNP (p=0.13) or higher probability of multivessel disease (p=0.22) or presence of ≥1 significant stenosis (p=0.31).

Conclusions

In this population of diabetic patients with a first episode of ACS, prior use of ASA in the context of primary prevention was associated with a significant lower rate of ST-segment elevation myocardial infarction.

Funding Acknowledgement

Type of funding source: None

Saprolegnia infection after vaccination in Atlantic salmon is associated with differential expression of stress and immune genes in the host

This study assessed the impact of routine vaccination of Atlantic salmon pre-smolts on gene expression and the possible link to saprolegniosis on Scottish fish farms. Fish were in 4 different groups 1) 'control' - fish without handling or vaccination 2) 'vaccinated' - fish undergoing full vaccination procedure 3) 'non vaccinated' - fish undergoing full vaccination procedure but not vaccinated and 4) 'vaccinated-MH' - fish undergoing vaccination, but procedure involved minimal handling. A strong increase in cortisol and glucose levels was observed after 1 h in all groups relative to the control group. Only in the non-vaccinated group did the level decrease to near control levels by 4 h. Expression levels of six stress marker genes in general for all groups showed down regulation over a 9-day sampling period. In contrast, expression levels for immune response genes in the head kidney showed significant up-regulation for all eight genes tested for both vaccinated groups whereas the non-vaccinated group showed up-regulation for only MHC-II and IL-6b in comparison to the control. Both the vaccination procedure and the administration of the vaccine itself were factors mediating changes in gene expression consistent with fish being susceptible to natural occurring saprolegniosis following vaccination.

P887 Two sides of the same mass

Echocardiography (echo) remains the first-line imaging modality for the evaluation of cardiac masses. Three-dimensional (3D) echo, either transthoracic or transesophageal (TTE and TEE respectively), has allowed for better definition imaging, providing more information about the size, mobility, attachment and relation of these lesions with cardiac structures. Nevertheless, due to its superior tissue characterization capability, other imaging techniques, such as cardiac magnetic resonance (CMR), are very helpful in the differential diagnosis, making multimodality imaging the most attractive option for the study of intracardiac masses.

We present the case of a 85 year-old male, with paroxysmal atrial fibrillation (under effective anticoagulation), type 2 diabetes mellitus, hypertension, referred for the study of an asymptomatic cardiac mass found in a routine TTE. There were no relevant findings on physical examination. The TTE showed a bilobar spheroid mass, in the right atrium, attached to the interatrial septum, with 33x23mm and regular edges. A 3D TEE was performed confirming the previous findings, but also showing extension of this mass through the fossa ovalis membrane, reaching the left atrium; this aspect raised the doubt about either protrusion or invasion of the left atrium and, respectively, a benign (like a myxoma) versus malignant behaviour (such as a sarcoma). To better characterize this lesion, a CMR was ordered, which revealed a bilobar heterogeneous mass, attached to the right side of the interatrial septum, at the fossa ovalis membrane, without signs of adjacent tissue invasion, namely unequivocal invasion of the left atrium; it presented with intermediate T1 signal, hyperintense T2 signal and heterogeneous pattern of gadolinium enhancement, features mostly in favour of a right atrial myxoma. The complimentary study found no other relevant changes, namely no findings suggestive of endocarditis (negative blood cultures), autoimmune disease or malignancy. The patient refused undergoing heart surgery and, therefore, kept follow-up with clinical and echocardiographic stability.

Although histological examination remains the only tool for definitive diagnosis, multimodality imaging allows a quite comprehensive evaluation of intracardiac masses, enlightening the differential diagnosis. Here the imaging findings helped to establish a benign origin as the most likely, very important in this case of a probable right atrial myxoma, due to its peculiar protrusion to the left atrium through the fossa ovalis membrane.

Abstract P887 Figure. atrial myxoma

1098 Atrial thickening: a surprisingly "gouty" heart

Case Presentation

A 49 year-old male presented to the emergency department with fever and lower limb myalgia for 5 days. His past history was notable for acute episodes of microcrystalline pyrophosphate oligoarthritis for which he was receiving allopurinol 100mg, colchicine 1mg and prednisolone 5mg. Physical examination was unrevealing. Laboratory workup showed normocytic normochromic anemia (Hb 12.8g/dL), leukocytosis (22 490 /mm3), neutrophilia (86.8%), increased C-reactive protein (CRP

26mg/dL), low procalcitonin (0.82ng/mL) and mildly elevated creatinine-kinase (83 UI/L). The patient was admitted with fever of unknown origin and started on ceftriaxone after blood and urine cultures.

He remained febrile with persistently heightened inflammation. Cultures, infectious and auto-immune tests, bone marrow biopsy, myelogram and abdominopelvic CT scan were negative. Three weeks later, syncope due to complete atrioventricular (AV) block led to temporary pacemaker implantation. Transoesophageal echocardiography (TOE) revealed a left atrial (LA) wall thickening,

evident on MRI as an 8-10mm T2-hyperintensity sign, with right atrial (RA) and ventricular sparing. PET/CT scan showed an 18F FDG uptake exclusively in the LA. As a neoplasia was highly suspected, a transspeptal biopsy was attempted, yet the sample was scarce for analysis. Thus, a biopsy via sternotomy was performed, now sampling both the LA and RA. Indeed, repeated TOE showed de novo RA involvement with a prominent nodular finding (19x24mm) in the lateral wall.

Myocyte inflammation and necrosis accompanied with granulocyte infiltration (mostly neutrophils but also eosinophils) was observed in all samples. There were no findings suggestive of neoplasia. The patient was still on allopurinol, which has been reported to involve the myocardium in a late (type IV) hypersensitivity reaction (the so-called DRESS syndrome), even in the absence of systemic inflammation. Thus, allopurinol was stopped and 1mg/Kg prednisolone was started. The patient

significantly improved and was discharged home with negative CRP the following two weeks. After 1 month, MRI was repeated and no atrial inflammation was found. After 4 months follow-up, he is doing well on 2.5mg of prednisolone and febuxostat 80mg.

P5242Gender equality in acute coronary syndrome: modern times, old habits?

Introduction

Historically, women with acute coronary syndrome (ACS) have worse outcomes compared with men. Differences in clinical, demographic characteristics and treatment may explain this result. In recent times with new diagnostic capabilities and revascularization therapies this panorama may be changing.

Methods

Single-center retrospective study comparing gender differences in ACS patients from 2012 to 2017. Two groups were formed comparing women and men: Group A: years 2012 to 2014 and group B: years 2015 to 2017.

Results

From 2012 to 2017 we identified 1091 patients with ACS. Of them 356 (32,6%) were women and NSTEMI (60%) was the most frequent type of ACS in this group. Women with ACS were older than men (73 vs 66 years) had more arterial hypertension (83,4% vs 68,3% p<0,001), diabetes mellitus (46,3% vs 30,9% p<0,001) and were less frequently smokers (6,5% vs 25,3% p<0,01). Dyspnea as the predominant symptom was more frequent in women (10,4% vs 5,2% p=0,002) who were less submitted to invasive strategy (63,2% vs 74,7% p<0,001) where non obstructive disease was more prevalent compared to men (9,8% vs 3,3% p<0,001). In-hospital mortality was greater in the women group (7,9% vs 3,7% p=0.005). There were no differences between groups in hospitalization or cardiovascular mortality over 1-year follow-up. When comparing Group A with Group B there were differences in hospitalization at 1 year (Group A 15,4% vs 9,3% p=0,029, Group B 11% vs 12,4% p=0,766), in-hospital women mortality (Group A 9,5% vs 3,6 p=0,005, Group B 5,8 vs 3,8% p=0,346) and coronary invasive angiography (Group A 61,2% vs 80,2% p<0,001 vs Group B 65,8 vs 68,5%, p=0,606).

Conclusion

Different demographic and clinical presentation as well as in-hospital and 1-year outcomes were present in our study population: while in Group A threre were significant gender differences regarding hospitalization and in-hospital mortality, those differences faded away in Group B. Efforts should be made to lessen gender differences in treatment and assistance knowing the different demographical and clinical patient profile.

Exophiala angulospora infection in hatchery-reared lumpfish (Cyclopterus lumpus) broodstock

Samples from moribund lumpfish were collected in a marine hatchery in Scotland in 2015. Black nodules were noted on the skin, and gills and fungal hyphae were extensively distributed in musculature and internal organs. Multifocal chronic inflammatory lesions displaced structures in all affected organs. Mortalities commenced on completion of spawning in May and were evenly distributed over the second year in the temperature range 11-15°C. The main systemic infection causing agent was initially identified based on morphological characteristics as an Exophiala species. Ribosomal DNA (rDNA) ITS regions of the isolates were subsequently sequenced confirming the isolates belonged to Exophiala genus. All isolates fell in a single phylogenetic cluster, which is represented by Exophiala angulospora. Fish were treated with either formalin or Bronopol or a combination of both, but there was no effect on the pattern or numbers of mortalities. Isolates were also tested against three different concentrations of Latrunculin A, Amphotericin B and Itraconazole with no success. It is of utmost importance to increase the knowledge on pathogen-host interactions to successfully develop sustainable control methods.

Predictors and outcomes of disseminated tuberculosis in an intermediate burden setting

SETTING

University-affiliated hospital located in Porto, North Portugal, an area with a low to intermediate incidence of tuberculosis (TB).

OBJECTIVE

To identify predictors and outcomes of disseminated TB (dTB).

DESIGN

A cohort of patients diagnosed with TB between 2007 and 2013 was retrospectively analysed. Patients with dTB criteria were characterized and compared to single organ TB cases. Factors independently associated with dTB were determined by multivariate logistic regression analysis.

RESULTS

A total of 744 patients were analysed, including 145 with dTB. Independent risk factors for dTB were pharmacological immunosuppression (OR 5.6, 95% CI 2.8-11.3), HIV infection (OR 5.1, 95% CI 3.1-8.3), chronic liver failure or cirrhosis (OR 2.3, 95% CI 1.4-4.1) and duration of symptoms (OR 2.3, 95% CI 1.4-3.8). Compared to single organ TB, the clinical presentation of dTB patients differed by the absence of haemoptysis (OR 3.2, 95% CI 1.3-8.4) and of dyspnoea (OR 1.9, 95% CI 1.2-3.1), presence of weight loss (OR 1.8, 95% CI 1.1-2.9), night sweats (OR 1.7, 95% CI 1.1-2.7) and bilateral lung involvement (OR 4.4, 95% CI 2.8-7.1). Mortality and time until culture conversion were higher for dTB patients, although not reaching statistical significance.

CONCLUSION

Immunosuppressive conditions and chronic liver failure or cirrhosis were associated with increased risk of dTB. The haematogenous spread may be dependent on longer symptomatic disease and usually progresses with bilateral lung involvement.

ENVIRONMENTAL MONITORING WITH PASSIVE DETECTORS AT CTN IN PORTUGAL

The aim of this work is to present the methods in use for environmental dose assessment with passive detectors at Campus Tecnológico e Nuclear (CTN) of Instituto Superior Técnico, in Portugal. The methods are based on LiF:Mg,Ti (TLD-100) detectors inserted in Harshaw holders placed at four locations and exchanged on a quarterly basis. An initial group of measurements allowed the estimation of the time interval necessary to attain a stable value, the determination of a fading factor, as well as the calculation method for the assessment of the ambient dose equivalent rate.

FADING EFFECT OF LiF:Mg,Ti AND LiF:Mg,Cu,P Ext-Rad AND WHOLE-BODY DETECTORS

Thermoluminescence dosemeters are widely used in individual and environmental monitoring. The aim of this work was to compare the thermal stability of dosemeters of the Ext-Rad and whole-body card types with LiF:Mg,Ti and LiF:Mg,Cu,P detectors stored at different temperatures and periods. The dosemeters were stored at 0°C, room temperature and 40°C for periods that lasted 8, 30, 45, 90 and 120 d. In general, TLD-100H detectors present higher TL signal stability than TLD-100 detectors. The intensity of the signal remained constant for both materials for storage periods at 0°C. At RT the same results was observed for TLD-100H. For TLD-100 detectors, a maximum variation of 22 % was registered for the longest period. At 40°C the TL signal decreased with storage time for both detectors. The TL signal of TLD-100H detectors presented maximum variations of 12 % whereas for TLD-100 detectors, larger variations of 25 % were observed.

Functional characterization of a tyrosinase gene from the oomycete Saprolegnia parasitica by RNAi silencing

Here we describe the first application of transient gene silencing in Saprolegnia parasitica, a pathogenic oomycete that infects a wide range of fish, amphibians, and crustaceans. A gene encoding a putative tyrosinase from S. parasitica, SpTyr, was selected to investigate the suitability of RNA-interference (RNAi) to functionally characterize genes of this economically important pathogen. Tyrosinase is a mono-oxygenase enzyme that catalyses the O-hydroxylation of monophenols and subsequent oxidation of O-diphenols to quinines. These enzymes are widely distributed in nature, and are involved in the melanin biosynthesis. Gene silencing was obtained by delivering in vitro synthesized SpTyr dsRNA into protoplasts. Expression analysis, tyrosinase activity measurements, and melanin content analysis confirmed silencing in individual lines. Silencing of SpTyr resulted in a decrease of tyrosinase activity between 38 % and 60 %, dependent on the level of SpTyr-expression achieved. The SpTyr-silenced lines displayed less pigmentation in developing sporangia and occasionally an altered morphology. Moreover, developing sporangia from individual silenced lines possessed a less electron dense cell wall when compared to control lines, treated with GFP-dsRNA. In conclusion, the tyrosinase gene of S. parasitica is required for melanin formation and transient gene silencing can be used to functionally characterize genes in S. parasitica.

•

Successful transient gene silencing in Saprolegnia parasitica through RNAi.

•

Silencing a tyrosinase in S. parasitica results in reduced melanin formation.

•

Silencing a tyrosinase in S. parasitica results in aberrant sporangia formation.

Cushing's syndrome due to ectopic ACTH production by a nasal paraganglioma

Ectopic secretion of ACTH is an infrequent cause of Cushing's syndrome. We report a case of ectopic ACTH syndrome caused by a nasal paraganglioma, a 68-year-old female with clinical features of Cushing's syndrome, serious hypokalaemia and a right paranasal sinus' lesion. Cranial magnetic resonance image showed a 46-mm mass on the right paranasal sinuses. Endocrinological investigation confirmed the diagnosis of ectopic ACTH production. Resection of the tumour normalised ACTH and cortisol secretion. The tumour was found to be a paraganglioma through microscopic analysis. On follow-up 3 months later, the patient showed nearly complete clinical recovery. Ectopic ACTH syndrome due to nasal paraganglioma is extremely uncommon, as only two other cases have been discussed in the literature.

Distinctive expansion of potential virulence genes in the genome of the oomycete fish pathogen Saprolegnia parasitica

Oomycetes in the class Saprolegniomycetidae of the Eukaryotic kingdom Stramenopila have evolved as severe pathogens of amphibians, crustaceans, fish and insects, resulting in major losses in aquaculture and damage to aquatic ecosystems. We have sequenced the 63 Mb genome of the fresh water fish pathogen, Saprolegnia parasitica. Approximately 1/3 of the assembled genome exhibits loss of heterozygosity, indicating an efficient mechanism for revealing new variation. Comparison of S. parasitica with plant pathogenic oomycetes suggests that during evolution the host cellular environment has driven distinct patterns of gene expansion and loss in the genomes of plant and animal pathogens. S. parasitica possesses one of the largest repertoires of proteases (270) among eukaryotes that are deployed in waves at different points during infection as determined from RNA-Seq data. In contrast, despite being capable of living saprotrophically, parasitism has led to loss of inorganic nitrogen and sulfur assimilation pathways, strikingly similar to losses in obligate plant pathogenic oomycetes and fungi. The large gene families that are hallmarks of plant pathogenic oomycetes such as Phytophthora appear to be lacking in S. parasitica, including those encoding RXLR effectors, Crinkler's, and Necrosis Inducing-Like Proteins (NLP). S. parasitica also has a very large kinome of 543 kinases, 10% of which is induced upon infection. Moreover, S. parasitica encodes several genes typical of animals or animal-pathogens and lacking from other oomycetes, including disintegrins and galactose-binding lectins, whose expression and evolutionary origins implicate horizontal gene transfer in the evolution of animal pathogenesis in S. parasitica.

Fish are an increasingly important source of animal protein globally, with aquaculture production rising dramatically over the past decade. Saprolegnia is a fungal-like oomycete and one of the most destructive fish pathogens, causing millions of dollars in losses to the aquaculture industry annually. Saprolegnia has also been linked to a worldwide decline in wild fish and amphibian populations. Here we describe the genome sequence of the first animal pathogenic oomycete and compare the genome content with the available plant pathogenic oomycetes. We found that Saprolegnia lacks the large effector families that are hallmarks of plant pathogenic oomycetes, showing evolutionary adaptation to the host. Moreover, Saprolegnia harbors pathogenesis-related genes that were derived by lateral gene transfer from the host and other animal pathogens. The retrotransposon LINE family also appears to be acquired from animal lineages. By transcriptome analysis we show a high rate of allelic variation, which reveals rapidly evolving genes and potentially adaptive evolutionary mechanisms coupled to selective pressures exerted by the animal host. The genome and transcriptome data, as well as subsequent biochemical analyses, provided us with insight in the disease process of Saprolegnia at a molecular and cellular level, providing us with targets for sustainable control of Saprolegnia.

Immune gene expression in trout cell lines infected with the fish pathogenic oomycete Saprolegnia parasitica

The oomycete Saprolegnia parasitica causes significant losses in the aquaculture industry, mainly affecting salmon, trout and catfish. Since the ban of malachite green, effective control measures are currently not available prompting a re-evaluation of the potential for immunological intervention. In this study, the immune response of salmonid cells is investigated at the transcript level, by analysis of a large set of immune response genes in four different rainbow trout cell lines (RTG-2, RTGill, RTL and RTS11) upon infection with S. parasitica. Proinflammatory cytokine transcripts were induced in all four cell lines, including IL-1β1, IL-8, IL-11, TNF-α2, as well as other components of the innate defences, including COX-2, the acute phase protein serum amyloid A and C-type lectin CD209a and CD209b. However, differences between the four cell lines were found. For example, the fold change of induction was much higher in the epithelial RTL and macrophage-like RTS11 cell lines compared to the fibroblast cell lines RTG-2 and RTGill. Several antimicrobial peptides (AMPs) were also up-regulated in response to Saprolegnia infection, including hepcidin and cathelicidin 1 (rtCATH1) and 2 (rtCATH2). An rtCATH2 peptide was synthesised and tested for activity and whilst it showed no killing activity for zoospores, it was able to delay sporulation of S. parasitica. These results demonstrate that particular immune genes are up-regulated in response to S. parasitica infection and that AMPs may play a crucial role in the first line of defence against oomycetes in fish.

CrmE, a novel soluble tumor necrosis factor receptor encoded by poxviruses

Cytokines and chemokines play a critical role in both the innate and acquired immune responses and constitute prime targets for pathogen sabotage. Molecular mimicry of cytokines and cytokine receptors is a mechanism encoded by large DNA viruses to modulate the host immune response. Three tumor necrosis factor receptors (TNFRs) have been identified in the poxvirus cowpox virus. Here we report the identification and characterization of a fourth distinct soluble TNFR, named cytokine response modifier E (CrmE), encoded by cowpox virus. The crmE gene has been sequenced in strains of the orthopoxviruses cowpox virus, ectromelia virus, and camelpox virus, and was found to be active in cowpox virus. crmE is expressed as a secreted 18-kDa protein with TNF binding activity. CrmE was produced in the baculovirus and vaccinia virus expression systems and was shown to bind human, mouse, and rat TNF, but not human lymphotoxin alpha, conjugates of lymphotoxins alpha and beta, or seven other ligands of the TNF superfamily. However, CrmE protects cells only from the cytolytic activity of human TNF. CrmE is a new member of the TNFR superfamily which is expressed as a soluble molecule that blocks the binding of TNF to high-affinity TNFRs on the cell surface. The remarkable finding of a fourth poxvirus-encoded TNFR suggests that modulation of TNF activity is complex and represents a novel viral immune evasion mechanism.