"Limiting access to iron decreases infection of Atlantic salmon SHK-1 cells with bacterium Piscirickettsia salmonis".

BACKGROUND: Vertebrate hosts limit the availability of iron to microbial pathogens in order to nutritionally starve the invaders. The impact of iron deficiency induced by the iron chelator deferoxamine mesylate (DFO) was investigated in Atlantic salmon SHK-1 cells infected with the facultative intracellular bacterium Piscirickettsia salmonis. RESULTS: Effects of the DFO treatment and P. salmonis on SHK-1 cells were gaged by assessing cytopathic effects, bacterial load and activity, and gene expression profiles of eight immune biomarkers at 4- and 7-days post infection (dpi) in the control group, groups receiving single treatments (DFO or P. salmonis) and their combination. The chelator appears to be well-tolerated by host cells, while it had a negative impact on the number of bacterial cells and associated cytotoxicity. DFO alone had minor effects on gene expression of SHK-1 cells, including an early activation of IL-1ß at 4 dpi. In contrast to few moderate changes induced by single treatments (either infection or chelator), most genes had highest upregulation in the infected groups receiving DFO. The mildest induction of hepcidin-1 (antimicrobial peptide precursor and regulator of iron homeostasis) was observed in cells exposed to DFO alone, followed by P. salmonis infected cells while the addition of DFO to infected cells further increased the mRNA abundance of this gene. Transcripts encoding TNF-α (immune signaling) and iNOS (immune effector) showed sustained increase at both time points in this group while cathelicidin-1 (immune effector) and IL-8 (immune signaling) were upregulated at 7 dpi. The stimulation of protective gene responses seen in infected cultures supplemented with DFO coincided with the reduction of bacterial load and activity (judged by the expression of P. salmonis 16S rRNA), and damage to cultured host cells. CONCLUSION: The absence of immune gene activation under normal iron conditions suggests modulation of host responses by P. salmonis. The negative effect of iron deficiency on bacteria likely allowed host cells to respond in a more protective manner to the infection, further decreasing its progression. Presented findings encourage in vivo exploration of iron chelators as a promising strategy against piscirickettsiosis.

Transcriptome Profiling of Atlantic Salmon (Salmo salar) Parr With Higher and Lower Pathogen Loads Following Piscirickettsia salmonis Infection.

Salmonid rickettsial septicemia (SRS), caused by Piscirickettsia salmonis, is one of the most devastating diseases of salmonids. However, the transcriptomic responses of Atlantic salmon (Salmon salar) in freshwater to an EM-90-like isolate have not been explored. Here, we infected Atlantic salmon parr with an EM-90-like isolate and conducted time-course qPCR analyses of pathogen load and four biomarkers (campb, hampa, il8a, tlr5a) of innate immunity on the head kidney samples. Transcript expression of three of these genes (except hampa), as well as pathogen level, peaked at 21 days post-injection (DPI). Multivariate analyses of infected individuals at 21 DPI revealed two infection phenotypes [lower (L-SRS) and higher (H-SRS) infection level]. Five fish from each group (Control, L-SRS, and H-SRS) were selected for transcriptome profiling using a 44K salmonid microarray platform. We identified 1,636 and 3,076 differentially expressed probes (DEPs) in the L-SRS and H-SRS groups compared with the control group, respectively (FDR = 1%). Gene ontology term enrichment analyses of SRS-responsive genes revealed the activation of a large number of innate (e.g. "phagocytosis", "defense response to bacterium", "inflammatory response") and adaptive (e.g. "regulation of T cell activation", "antigen processing and presentation of exogenous antigen") immune processes, while a small number of general physiological processes (e.g. "apoptotic process", development and metabolism relevant) was enriched. Transcriptome results were confirmed by qPCR analyses of 42 microarray-identified transcripts. Furthermore, the comparison of individuals with differing levels of infection (H-SRS vs. L-SRS) generated insights into the biological processes possibly involved in disease resistance or susceptibility. This study demonstrated a low mortality (~30%) EM-90-like infection model and broadened the current understanding of molecular pathways underlying P. salmonis-triggered responses of Atlantic salmon, identifying biomarkers that may assist to diagnose and combat this pathogen.

Transcriptomic Profiling of the Adaptive and Innate Immune Responses of Atlantic Salmon to Renibacterium salmoninarum Infection.

Bacterial Kidney Disease (BKD), which is caused by a Gram-positive, intracellular bacterial pathogen (Renibacterium salmoninarum), affects salmonids including Atlantic salmon (Salmo salar). However, the transcriptome response of Atlantic salmon to BKD remained unknown before the current study. We used a 44K salmonid microarray platform to characterise the global gene expression response of Atlantic salmon to BKD. Fish (~54 g) were injected with a dose of R. salmoninarum (H-2 strain, 2 × 108 CFU per fish) or sterile medium (control), and then head kidney samples were collected at 13 days post-infection/injection (dpi). Firstly, infection levels of individuals were determined through quantifying the R. salmoninarum level by RNA-based TaqMan qPCR assays. Thereafter, based on the qPCR results for infection level, fish (n = 5) that showed no (control), higher (H-BKD), or lower (L-BKD) infection level at 13 dpi were subjected to microarray analyses. We identified 6,766 and 7,729 differentially expressed probes in the H-BKD and L-BKD groups, respectively. There were 357 probes responsive to the infection level (H-BKD vs. L-BKD). Several adaptive and innate immune processes were dysregulated in R. salmoninarum-infected Atlantic salmon. Adaptive immune pathways associated with lymphocyte differentiation and activation (e.g., lymphocyte chemotaxis, T-cell activation, and immunoglobulin secretion), as well as antigen-presenting cell functions, were shown to be differentially regulated in response to BKD. The infection level-responsive transcripts were related to several mechanisms such as the JAK-STAT signalling pathway, B-cell differentiation and interleukin-1 responses. Sixty-five microarray-identified transcripts were subjected to qPCR validation, and they showed the same fold-change direction as microarray results. The qPCR-validated transcripts studied herein play putative roles in various immune processes including pathogen recognition (e.g., tlr5), antibacterial activity (e.g., hamp and camp), regulation of immune responses (e.g., tnfrsf11b and socs1), T-/B-cell differentiation (e.g., ccl4, irf1 and ccr5), T-cell functions (e.g., rnf144a, il13ra1b and tnfrsf6b), and antigen-presenting cell functions (e.g., fcgr1). The present study revealed diverse immune mechanisms dysregulated by R. salmoninarum in Atlantic salmon, and enhanced the current understanding of Atlantic salmon response to BKD. The identified biomarker genes can be used for future studies on improving the resistance of Atlantic salmon to BKD.

How European primary care practitioners think the timeliness of cancer diagnosis can be improved: a thematic analysis.

BACKGROUND: National European cancer survival rates vary widely. Prolonged diagnostic intervals are thought to be a key factor in explaining these variations. Primary care practitioners (PCPs) frequently play a crucial role during initial cancer diagnosis; their knowledge could be used to improve the planning of more effective approaches to earlier cancer diagnosis. OBJECTIVES: This study sought the views of PCPs from across Europe on how they thought the timeliness of cancer diagnosis could be improved. DESIGN: In an online survey, a final open-ended question asked PCPs how they thought the speed of diagnosis of cancer in primary care could be improved. Thematic analysis was used to analyse the data. SETTING: A primary care study, with participating centres in 20 European countries. PARTICIPANTS: A total of 1352 PCPs answered the final survey question, with a median of 48 per country. RESULTS: The main themes identified were: patient-related factors, including health education; care provider-related factors, including continuing medical education; improving communication and interprofessional partnership, particularly between primary and secondary care; factors relating to health system organisation and policies, including improving access to healthcare; easier primary care access to diagnostic tests; and use of information technology. Re-allocation of funding to support timely diagnosis was seen as an issue affecting all of these. CONCLUSIONS: To achieve more timely cancer diagnosis, health systems need to facilitate earlier patient presentation through education and better access to care, have well-educated clinicians with good access to investigations and better information technology, and adequate primary care cancer diagnostic pathway funding.

Identifying important health system factors that influence primary care practitioners' referrals for cancer suspicion: a European cross-sectional survey.

OBJECTIVES: Cancer survival and stage of disease at diagnosis and treatment vary widely across Europe. These differences may be partly due to variations in access to investigations and specialists. However, evidence to explain how different national health systems influence primary care practitioners' (PCPs') referral decisions is lacking.This study analyses health system factors potentially influencing PCPs' referral decision-making when consulting with patients who may have cancer, and how these vary between European countries. DESIGN: Based on a content-validity consensus, a list of 45 items relating to a PCP's decisions to refer patients with potential cancer symptoms for further investigation was reduced to 20 items. An online questionnaire with the 20 items was answered by PCPs on a five-point Likert scale, indicating how much each item affected their own decision-making in patients that could have cancer. An exploratory factor analysis identified the factors underlying PCPs' referral decision-making. SETTING: A primary care study; 25 participating centres in 20 European countries. PARTICIPANTS: 1830 PCPs completed the survey. The median response rate for participating centres was 20.7%. OUTCOME MEASURES: The factors derived from items related to PCPs' referral decision-making. Mean factor scores were produced for each country, allowing comparisons. RESULTS: Factor analysis identified five underlying factors: PCPs' ability to refer; degree of direct patient access to secondary care; PCPs' perceptions of being under pressure; expectations of PCPs' role; and extent to which PCPs believe that quality comes before cost in their health systems. These accounted for 47.4% of the observed variance between individual responses. CONCLUSIONS: Five healthcare system factors influencing PCPs' referral decision-making in 20 European countries were identified. The factors varied considerably between European countries. Knowledge of these factors could assist development of health service policies to produce better cancer outcomes, and inform future research to compare national cancer diagnostic pathways and outcomes.

Randomized Controlled Study to Evaluate the Efficacy of Adalimumab in Patients with Different Forms of Refractory Uveitis.

PURPOSE: TNF alpha inhibitors have revolutionized the care of vision-threatening uveitis. This study evaluated the efficacy of adalimumab (ADA) for the treatment of refractory noninfectious uveitis. DESIGN: Randomized, prospective, controlled, two-center clinical trial Methods: Patients with active uveitis despite combined oral low-dose prednisolone and immunosuppression were randomized for additional ADA with corticosteroids in a fixed tapering regime, or corticosteroids only. Primary outcome measure at three months was improved best-corrected visual acuity (BCVA; >2 lines). In case of treatment failure, switch to the other arm was possible. RESULTS: Twenty-five patients (10 ADA, 15 controls) were included. BCVA increased with ADA by > 2 lines in 6/10 patients (60%; mean increase of 0.23 logMAR), but in only 2/15 from controls (13%, mean increase of 0.04 logMAR, Fisher´s exact test p = 0.00221). CONCLUSIONS: The results show superiority of ADA over controls in severe ocular inflammation including anterior uveitis.

Experiences with rituximab for the treatment of autoimmune diseases with ocular involvement.

OBJECTIVE: To report the efficacy of rituximab (RTX) in the treatment of ocular or orbital inflammation accompanying autoimmune diseases refractory to previous standard immunosuppressive therapy. METHODS: We reviewed medical records of 9 consecutive patients with noninfectious ocular or orbital inflammation treated with RTX. RESULTS: Over a mean followup of 42 months, 7 patients were in clinical remission, 1 had partial response to treatment, and 1 did not respond. Best corrected visual acuity improved ≥ 1 line in 4 patients, was stable in another 4 patients, and worsened in 1. Concomitant immunosuppressive therapy was tapered in 6 cases. Systemic corticosteroids were tapered or kept below 7.5 mg a day in 5 patients 1 year after the first RTX cycle. CONCLUSION: RTX therapy, in patients who are refractory to standard immunosuppressive therapy, was effective and showed a beneficial response to treatment including induction of clinical remission of inflammation in most patients.

Interferon versus methotrexate in intermediate uveitis with macular edema: results of a randomized controlled clinical trial.

PURPOSE: To compare interferon (IFN) beta with methotrexate (MTX) in the treatment of intermediate uveitis with macular edema. DESIGN: Monocentric, prospective, randomized, controlled clinical trial. SETTING: Specialized uveitis center at the University of Heidelberg. PATIENT OR STUDY POPULATION: Patients with either primary intermediate uveitis or uveitis associated with multiple sclerosis. MAIN INCLUSION CRITERIA: Visual acuity of 20/30 or worse (0.2 logarithm of the minimal angle of resolution) and macular edema of more than 250 µm (central 1-mm in optical coherence tomography; Stratus). Randomization into either IFN beta 44 µg subcutaneously 3 times weekly or 20 mg MTX subcutaneously once weekly. MAIN OUTCOME MEASURES: At 3 months, the primary outcome parameter of mean change in visual acuity was evaluated and efficacy was determined. Secondary parameters were macular edema by optical coherence tomography, inflammatory activity, and retinal sensitivity by microperimetry (MP-1; Nidek). In case of treatment failure, switching to the other treatment arm was possible. RESULTS: Nineteen patients were included. Ten were randomized to MTX, and 9 were randomized to IFN beta. At 3 months, visual acuity improved a mean 0.31 logarithm of the minimal angle of resolution (range, -0.02 to -0.96, 15.6 letters on the Early Treatment Diabetic Retinopathy Study chart) in the IFN beta group versus a mean 0.09 logarithm of the minimal angle of resolution (range, 0.12 to -0.38, 4.7 letters) in the MTX arm (P = .0435, Mann-Whitney U test). Macular thickness decreased by a mean of 206 µm (range, -41 to -416 µm) in the IFN arm, but increased by 47 µm (range, 108 to -28 µm) in the MTX group (P < .0001). CONCLUSIONS: Although the sample size is small, results of the trial support superiority of IFN beta over MTX in the treatment of macular edema in the setting of intermediate uveitis.

Clinical spectrum of tuberculous optic neuropathy.

PURPOSE: Tuberculous optic neuropathy may follow infection with Mycobacterium tuberculosis or administration of the bacille Calmette-Guerin. However, this condition is not well described in the ophthalmic literature. METHODS: Ophthalmologists, identified through professional electronic networks or previous publications, collected standardized clinical data relating to 62 eyes of 49 patients who they had managed with tuberculous optic neuropathy. RESULTS: Tuberculous optic neuropathy was most commonly manifested as papillitis (51.6 %), neuroretinitis (14.5 %), and optic nerve tubercle (11.3 %). Uveitis was an additional ocular morbidity in 88.7 % of eyes. In 36.7 % of patients, extraocular tuberculosis was present. The majority of patients (69.4 %) had resided in and/or traveled to an endemic area. Although initial visual acuity was 20/50 or worse in 62.9 % of 62 eyes, 76.7 % of 60 eyes followed for a median of 12 months achieved visual acuities of 20/40 or better. Visual field defects were reported for 46.8 % of eyes, but these defects recovered in 63.2 % of 19 eyes with follow-up. CONCLUSION: Visual recovery from tuberculous optic neuropathy is common, if the diagnosis is recognized and appropriate treatment is instituted. A tuberculous etiology should be considered when evaluating optic neuropathy in persons from endemic areas.

Difficulties of interpreting Borrelia serology in patients with uveitis.

PURPOSE: We aimed to review all uveitis patients with a positive Borrelia serology to evaluate positive results in uveitis subtypes. Further we wanted to test a self-assembled Interferon gamma release assay (IGRA) as a possible supplement method in these patients. METHODS: Patients where serology for Borrelia was ordered from September 2005 to May 2008, were identified by database search. Patients with positive results in ELISA and Western Blot were retested by a self-assembled IGRA. Bayes Theorem was applied. RESULTS: Testing for Borrelia was ordered for 184 patients. 18 patients (9,8%) showed positive results. 11 were positive for IgG (5,9 %), 3 were positive for IgG and IgM (1,6 %) and 4 for IgM (2,1%). Applying Bayes Theorem, we calculated a posttest-probability of 9% in case of a positive test result. 16 of the 18 patients were retested by IGRA. None of them showed a positive result. CONCLUSIONS: A positive serology with uveitis as the only clinical symptom is not sufficient to confirm Borreliosis as 5,9 % of patients with uveitis and a positive IgG serology correspond to the normal spread of Borrelia in the population. Looking at posttest-probability shows a lot of false-positive test results when testing all uveitis patients for Borrelia routinely.

Concentration of infectious aquatic rhabdoviruses from freshwater and seawater using ultrafiltration.

Infectious hematopoietic necrosis virus (IHNV), viral hemorrhagic septicemia virus, and spring viremia of carp virus were concentrated and detected from freshwater and seawater samples by using hollow-fiber ultrafiltration. Within 60 min, virus in a 50-L freshwater or saltwater sample was concentrated more than 70-fold, and virus retention efficiencies were consistently greater than 88%. Retention efficiency was highly dependent upon concentrations of column blocking and sample stabilization solutions. A large column with a surface area of 1.15 m2 and a filtration capacity of 5-200 L exhibited optimal viral retention when blocked with 2% fetal bovine serum (FBS) and when the samples were supplemented with 0.1% FBS. Conversely, a small column with 100-fold less surface area and a filtering capacity of 0.5-2.0 L was optimized when blocked with 1% FBS and when the samples were supplemented with 0.1% FBS. The optimized ultrafiltration procedure was further validated with water from a tank that contained IHNV-exposed juvenile sockeye salmon Oncorhynchus nerka, resulting in an average virus retention efficiency of 91.6 +/- 4.1% (mean +/- SE). Virus quantification of concentrated samples demonstrated that IHNV shedding in sockeye salmon preceded mortality; shedding of the virus was observed to increase significantly as early as 7 d postchallenge and peaked at day 14, when virus levels reached 4.87 x 10(3) plaque-forming units/mL. We conclude that ultrafiltration is a reliable and effective method for concentrating viable aquatic rhabdoviruses from large volumes of water and has application for the analysis of environmental water samples.

Uveitis subtypes in a german interdisciplinary uveitis center--analysis of 1916 patients.

OBJECTIVE: Studies on the epidemiology of uveitis are rare and cohorts are small. We analyzed the frequencies of classified forms of uveitis in all patients at our center. METHODS: We studied 1916 consecutive patients with inflammatory eye disease. Data were analyzed regarding associated systemic disease, infection, ocular syndromes, anatomic localization, age, and sex. RESULTS: In 59.1% of patients, a classified form of uveitis was observed: associated systemic diseases in 43.7%, the most frequent ones sarcoidosis (17.4%) and ankylosing spondylitis (16.8%); ocular syndromes in 34.3%, the most frequent HLA-B27-positive anterior uveitis (AU; 35.1%) and Fuchs uveitis syndrome (FUS; 34.3%); and infections in 22.4%, the most frequent herpetic infections (46.1%) and toxoplasmosis (31.5%). We found AU in 45.4% of patients (15.4% HLA-B27-positive AU and 11.3% FUS), intermediate uveitis in 22.9% (unclassified 53.7% and multiple sclerosis 10.3%), and posterior uveitis in 13.5% (24.7% toxoplasmosis). Panuveitis was diagnosed in 6.2% of cases (Behçet's disease 12.6%; sarcoidosis 10.9%). The remaining 12.0% of cases showed extrauveal manifestations (scleritis, episcleritis, keratitis, optic neuritis, myositis, and orbital inflammation). CONCLUSION: We describe the largest cohort to date of consecutive patients from a specialized uveitis center. The high frequency of classified disease, nearly 60% in our clinic, shows the usefulness of an interdisciplinary approach, oriented on anatomic presentation.

Frequency of microsatellite instability in unselected sebaceous gland neoplasias and hyperplasias.

Sebaceous gland neoplasias are the cutaneous manifestation of the Muir-Torre syndrome, which is known to be a phenotypical variant of hereditary nonpolyposis colorectal cancer. Both hereditary nonpolyposis colorectal cancer and Muir-Torre syndrome are caused by inherited DNA mismatch repair defects. As a prominent molecular genetic feature, all tumors associated with a DNA mismatch repair defect exhibit high microsatellite instability. So far, the frequency of DNA mismatch repair defects in patients selected solely on the basis of a sebaceous gland tumor has never been determined. In order to estimate this frequency, we assessed microsatellite instability with up to 10 microsatellite markers in a newly collected unselected series of 25 sebaceous gland neoplasias (six sebaceous adenomas, 16 sebaceous epitheliomas, three sebaceous carcinomas) in comparison to 32 sebaceous gland hyperplasias from unrelated patients. As many as 15 of the 25 sebaceous gland neoplasias (60%), but only one of the 32 sebaceous gland hyperplasias (3%), exhibited high microsatellite instability. Thus, in our study, the majority of patients with a sebaceous gland neoplasia in contrast to patients with a sebaceous gland hyperplasia are highly suspicious for an inherited DNA mismatch repair defect. On the basis of the subsequently collected tumor histories, nine of the 15 patients with a high microsatellite unstable sebaceous gland neoplasia were identified to have Muir-Torre syndrome. In none of these cases, however, were the clinical Amsterdam criteria for diagnosing hereditary nonpolyposis colorectal cancer fulfilled. In the sebaceous tumors of the remaining six patients, high microsatellite instability was an incidental finding. In two of these six patients, single relatives were known to be affected with internal cancer; however, their family histories were not suggestive of Muir-Torre syndrome or hereditary nonpolyposis colorectal cancer. In comparison with microsatellite instability screening studies in a variety of other randomly selected tumors, our study identifies sebaceous gland neoplasias as tumors with the highest frequency of high microsatellite instability reported so far, whereas sebaceous gland hyperplasia rarely exhibits high microsatellite instability. Therefore, screening for microsatellite instability in sebaceous gland neoplasias will be of great value in the detection of an inherited DNA mismatch repair defect, which predisposes to various types of internal cancers.