Preference for biological motion is reduced in ASD: implications for clinical trials and the search for biomarkers

BACKGROUND

The neurocognitive mechanisms underlying autism spectrum disorder (ASD) remain unclear. Progress has been largely hampered by small sample sizes, variable age ranges and resulting inconsistent findings. There is a pressing need for large definitive studies to delineate the nature and extent of key case/control differences to direct research towards fruitful areas for future investigation. Here we focus on perception of biological motion, a promising index of social brain function which may be altered in ASD. In a large sample ranging from childhood to adulthood, we assess whether biological motion preference differs in ASD compared to neurotypical participants (NT), how differences are modulated by age and sex and whether they are associated with dimensional variation in concurrent or later symptomatology.

METHODS

Eye-tracking data were collected from 486 6-to-30-year-old autistic (N = 282) and non-autistic control (N = 204) participants whilst they viewed 28 trials pairing biological (BM) and control (non-biological, CTRL) motion. Preference for the biological motion stimulus was calculated as (1) proportion looking time difference (BM-CTRL) and (2) peak look duration difference (BM-CTRL).

RESULTS

The ASD group showed a present but weaker preference for biological motion than the NT group. The nature of the control stimulus modulated preference for biological motion in both groups. Biological motion preference did not vary with age, gender, or concurrent or prospective social communicative skill within the ASD group, although a lack of clear preference for either stimulus was associated with higher social-communicative symptoms at baseline.

LIMITATIONS

The paired visual preference we used may underestimate preference for a stimulus in younger and lower IQ individuals. Our ASD group had a lower average IQ by approximately seven points. 18% of our sample was not analysed for various technical and behavioural reasons.

CONCLUSIONS

Biological motion preference elicits small-to-medium-sized case-control effects, but individual differences do not strongly relate to core social autism associated symptomatology. We interpret this as an autistic difference (as opposed to a deficit) likely manifest in social brain regions. The extent to which this is an innate difference present from birth and central to the autistic phenotype, or the consequence of a life lived with ASD, is unclear.

OP0287 IMMUNOMODULATORY THERAPIES FOR SEVERE FORMS OF COVID-19: A SYSTEMATIC LITERATURE REVIEW TO INFORM EULAR POINTS TO CONSIDER

Background:

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) pandemic is a global health problem. Beside the specific pathogenic effect of SARS-CoV-2, a deleterious aberrant non-effective host immune response plays an important role especially in severe forms of COVID-19. There is intense investigation to explore the utility of immunomodulatory drugs commonly used in the Rheumatology arena as agents that may mitigate against COVID-19 to improve disease prognosis. Rheumatologists are used to the utilization of these immune targeted therapies.

Objectives:

To summarize the available information on the use of immunomodulatory agents in severe COVID-19.

Methods:

As part of a EULAR taskforce, a systematic literature search was conducted from January 2019 up to December 11, 2020. Two reviewers independently identified eligible studies according to the PICO framework P (population): patients with SARS-CoV-2 infection; I (intervention): any immunomodulator agent/strategy; C (comparator): any comparator; O (outcome) any clinical outcome including but not limited to mortality, admission to intensive care unit and clinical improvement. Data on efficacy and safety of immunomodulatory agents utilized therapeutically in SARS-CoV-2 infection at any stage were extracted. The risk of bias was assessed using validated tools.

Results:

Of 60372 records, 401 articles were eligible for inclusion. Studies were at variable risk of bias. Randomised controlled trials (RCTs) were available for the following drugs: hydroxychloroquine (N=12), glucocorticoids (N=6), tocilizumab (N= 4), convalescent plasma (N=4), interferon beta (N=2), IVIg (N=2) and N=1 each for anakinra, baricitinib, colchicine, leflunomide, ruxolitinib, interferon kappa, and vilobelimab. For glucocorticoids, dexamethasone reduced mortality only in patients requiring respiratory support; while methylprednisolone reduced mortality in patients aged 60 years or over. Data from RCTs on tocilizumab are conflicting and definite conclusions cannot be drawn at this point in time, but recent studies suggest possible benefit in patients requiring respiratory support. Hydroxychloroquine was not beneficial at any disease stage, one RCT with anakinra was negative, one RCT with baricitinib+remdesivir was positive, and individual trials testing some other compounds provided interesting, albeit preliminary, results.

Conclusion:

Although there is emerging evidence about immunomodulatory therapies for the management of COVID-19, conclusive data is scarce with some conflicting data. Since glucocorticoids seem to improve survival in some subsets of patients, RCTs comparing glucocorticoids alone versus glucocorticoids plus anti-cytokine/immunomodulatory treatment are warranted. This SLR informed the initiative to formulate EULAR points to consider on pathophysiology and use of immunomodulatory therapies in COVID-19.

Figure 1.

Forest plots showing the risk ratio (RR) and 95% confidence interval for mortality in randomized controlled trials divided by intervention. The latest follow-up available is reported in the timing column.

Disclosure of Interests:

None declared

POS0052 PATHOPHYSIOLOGY OF ACUTE RESPIRATORY SYNDROME CORONAVIRUS 2 INFECTION: A SYSTEMATIC LITERATURE REVIEW TO INFORM EULAR POINTS TO CONSIDER

Background:

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic is a global health problem. Beside the specific pathogenic effect of SARS-CoV-2, incompletely understood deleterious and aberrant host immune responses play critical roles in severe disease. Rheumatologists have the best experience of studying and treating these complicated hyperinflammatory processes.

Objectives:

To summarize the available information on pathophysiology of COVID-19.

Methods:

As part of a EULAR taskforce, two systematic literature reviews were performed one on pathophysiology and one on immunomodulatory therapies. Two reviewers independently identified eligible studies according to the following PICO framework: P (population): patients with SARS-CoV-2 infection; I (intervention): any intervention/no intervention; C (comparator): any comparator; O (outcome) any clinical or serological outcome including but not limited to immune cell phenotype and function and serum cytokine concentration. The results pertaining to pathophysiology of COVID-19 are presented here.

Results:

Of the 55496 records yielded, 85 articles were eligible for inclusion. Included studies were at variable risk of bias and exploring various aspects of disease pathogenesis from immune to non-immune cells (Table 1). Pro-inflammatory cytokines’ expression including IL-6, was increased, especially in severe COVID-19, although not as high as other states with severe systemic inflammation. Innate and adaptative immune cell compartments were differentially affected by SARS-CoV-2 infection: neutrophils displayed an immature differentiation state and also increased neutrophil extracellular traps (NETs) formation. Dendritic cell number was reduced and classical monocytes was increased although displaying a reduced expression of HLA-DR. The lymphoid compartment was also affected: lymphopenia was present with a reduced number of CD4+ and CD8+ T lymphocytes and more frequent PD1+CD8+ T cells corresponding to an exhausted phenotype. Antibody response to SARS-CoV-2 infection showed a high variability across individuals and disease spectrum. Multiparametric algorithms showed variable diagnostic performances in predicting survival, hospitalization, disease progression or severity, and mortality. Differences in SARS-CoV-2 manifestations in adults and children were highlighted.

Conclusion:

Overall, SARS-CoV-2 infection affects both innate and adaptative immune responses in a variable way, according to both disease severity and individual parameters. This SLR informs the EULAR points to consider on pathophysiology and use of immunomodulatory therapies in COVID-19.

Table 1.

Studies on SARS-CoV-2 infection pathogenesis

Research questionNCytokines profile7Immune profile18Algorithm17Children3Comorbidities1Endothelial dysfunction and platelets8Gut and microbiota3Genetics and variants8Histology7Antibodies profiles8Viral load and immune response4Interferon3Immunosenecsnce3Total90*

*Some manuscripts were including in several research questions. Total number of studies included n=85.

Disclosure of Interests:

Aurelie Najm Speakers bureau: BMS, Consultant of: BMS, Alessia Alunno: None declared, Xavier Mariette Speakers bureau: BMS, Eli Lilly, Galapagos, Gilead, GSK, Janssen, Novartis, Pfizer, Servier and UCB, Consultant of: BMS, Eli Lilly, Galapagos, Gilead, GSK, Janssen, Novartis, Pfizer, Servier and UCB, Benjamin Terrier Speakers bureau: Roche, Chugai, Vifor Pharma, GSK, AstraZeneca, Terumo BCT, LFB and Grifols, Consultant of: Roche, Chugai, Vifor Pharma, GSK, AstraZeneca, Terumo BCT, LFB and Grifols, Gabriele De Marco: None declared, Laura Mason: None declared, Jenny Emmel: None declared, Dennis McGonagle Speakers bureau: Abbvie, BMS, Celgene, Eli Lilly, Janssen, MSD, Novartis, Pfizer, Roche and UCB, Consultant of: Abbvie, BMS, Celgene, Eli Lilly, Janssen, MSD, Novartis, Pfizer, Roche and UCB, Pedro M Machado Speakers bureau: Abbvie, BMS, Celgene, Eli Lilly, Janssen, MSD, Novartis, Orphazyme, Pfizer, Roche and UCB, Consultant of: Abbvie, BMS, Celgene, Eli Lilly, Janssen, MSD, Novartis, Orphazyme, Pfizer, Roche and UCB.

Perioperative intravenous contrast administration and the incidence of acute kidney injury after major gastrointestinal surgery: prospective, multicentre cohort study

BACKGROUND

This study aimed to determine the impact of preoperative exposure to intravenous contrast for CT and the risk of developing postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery.

METHODS

This prospective, multicentre cohort study included adults undergoing gastrointestinal resection, stoma reversal or liver resection. Both elective and emergency procedures were included. Preoperative exposure to intravenous contrast was defined as exposure to contrast administered for the purposes of CT up to 7 days before surgery. The primary endpoint was the rate of AKI within 7 days. Propensity score-matched models were adjusted for patient, disease and operative variables. In a sensitivity analysis, a propensity score-matched model explored the association between preoperative exposure to contrast and AKI in the first 48 h after surgery.

RESULTS

A total of 5378 patients were included across 173 centres. Overall, 1249 patients (23·2 per cent) received intravenous contrast. The overall rate of AKI within 7 days of surgery was 13·4 per cent (718 of 5378). In the propensity score-matched model, preoperative exposure to contrast was not associated with AKI within 7 days (odds ratio (OR) 0·95, 95 per cent c.i. 0·73 to 1·21; P = 0·669). The sensitivity analysis showed no association between preoperative contrast administration and AKI within 48 h after operation (OR 1·09, 0·84 to 1·41; P = 0·498).

CONCLUSION

There was no association between preoperative intravenous contrast administered for CT up to 7 days before surgery and postoperative AKI. Risk of contrast-induced nephropathy should not be used as a reason to avoid contrast-enhanced CT.

Eurosibs: Towards robust measurement of infant neurocognitive predictors of autism across Europe

•

The Eurosibs consortium is a nine-site European neurocognitive study of infants with an older sibling with ASD.

•

Data quality assessments show that that neurocognitive measures hold promise for cross-site consistency in diverse populations.

•

We present robust data analysis pipelines and highlight challenges and opportunities for future multisite research efforts.

Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder that affects social communication skills and flexible behaviour. Developing new treatment approaches for ASD requires early identification of the factors that influence later behavioural outcomes. One fruitful research paradigm has been the prospective study of infants with a first degree relative with ASD, who have around a 20% likelihood of developing ASD themselves. Early findings have identified a range of candidate neurocognitive markers for later ASD such as delayed attention shifting or neural responses to faces, but given the early stage of the field most sample sizes are small and replication attempts remain rare. The Eurosibs consortium is a European multisite neurocognitive study of infants with an older sibling with ASD conducted across nine sites in five European countries. In this manuscript, we describe the selection and standardization of our common neurocognitive testing protocol. We report data quality assessments across sites, showing that neurocognitive measures hold great promise for cross-site consistency in diverse populations. We discuss our approach to ensuring robust data analysis pipelines and boosting future reproducibility. Finally, we summarise challenges and opportunities for future multi-site research efforts.

Hepatitis B and C among healthcare workers and patient groups at increased risk of iatrogenic transmission in the European Union/European Economic Area

In the European Union/European Economic Area (EU/EEA) approximately 9 million people are chronically infected with hepatitis B virus (HBV) or hepatitis C virus (HCV), and many are undiagnosed. Targeted active case finding initiatives are needed. Iatrogenic transmission of HBV/HCV is relevant in Europe but people at risk of infection are often overlooked. This study aimed to identify groups at increased risk of HBV/HCV infection due to iatrogenic transmission, including healthcare workers, and to estimate incidence and prevalence. PubMed and Embase were systematically searched in February 2017 using strings combining terms for HBV/HCV, occurrence and population subgroups. All retrieved publications were screened and included articles were quality assessed. A predefined set of variables were extracted, and detailed summary tables were developed per population group of interest, virus and outcome. Thirty-eight articles were included, two reported on HBV, 22 on HCV and 16 on both, contributing 70 estimates of prevalence or incidence among: haemodialysis recipients, diabetes patients, recipients of substances of human origin, recipients of medical/dental procedures and healthcare workers. Estimates varied widely from 0.4% to 11.7% for HBV and from 0.7% to over 90% for HCV with most being higher than in the general population. Despite the limited number of studies retrieved, mostly old and focused on populations with multiple risk factors, our findings highlight the importance of considering population groups at higher risk for HBV/HCV iatrogenic transmission as target groups for active case finding in the EU/EEA. Test offers should be guided by individual risk assessment alongside local epidemiological data and local context.

Brain connectivity changes occurring following cognitive behavioural therapy for psychosis predict long-term recovery

This corrects the article DOI: 10.1038/tp.2016.263.

Brain connectivity changes occurring following cognitive behavioural therapy for psychosis predict long-term recovery

Little is known about the psychobiological mechanisms of cognitive behavioural therapy for psychosis (CBTp) and which specific processes are key in predicting favourable long-term outcomes. Following theoretical models of psychosis, this proof-of-concept study investigated whether the long-term recovery path of CBTp completers can be predicted by the neural changes in threat-based social affective processing that occur during CBTp. We followed up 22 participants who had undergone a social affective processing task during functional magnetic resonance imaging along with self-report and clinician-administered symptom measures, before and after receiving CBTp. Monthly ratings of psychotic and affective symptoms were obtained retrospectively across 8 years since receiving CBTp, plus self-reported recovery at final follow-up. We investigated whether these long-term outcomes were predicted by CBTp-led changes in functional connections with dorsal prefrontal cortical and amygdala during the processing of threatening and prosocial facial affect. Although long-term psychotic symptoms were predicted by changes in prefrontal connections during prosocial facial affective processing, long-term affective symptoms were predicted by threat-related amygdalo-inferior parietal lobule connectivity. Greater increases in dorsolateral prefrontal cortex connectivity with amygdala following CBTp also predicted higher subjective ratings of recovery at long-term follow-up. These findings show that reorganisation occurring at the neural level following psychological therapy can predict the subsequent recovery path of people with psychosis across 8 years. This novel methodology shows promise for further studies with larger sample size, which are needed to better examine the sensitivity of psychobiological processes, in comparison to existing clinical measures, in predicting long-term outcomes.

Syphilis sero-positivity among pregnant women attending public antenatal clinics: A five-year analysis from 15 public clinics in Gaborone, Botswana

Background: The prevalence of syphilis in pregnancy varies across the globe and among different age groups within the same country. In sub-Saharan Africa, syphilis prevalence among pregnant women has been found to range from 2.5 to 18% among antenatal clinic attendees, with the highest prevalence in the age group 35–49 years. Also, it is higher in the rural than urban clinics.Objectives: To determine trends in syphilis prevalence using the Venereal Disease Research Laboratory (VDRL) and the Rapid Plasma Reagin (RPR) test among pregnant women attending the public antenatal clinics in Gaborone, Botswana (2004–2008).Study design: Cross-sectional study using routinely collected antenatal data.Results: The overall syphilis prevalence amongst pregnant women in Gaborone, Botswana decreased from 2.96% (95% CI, 2.55– 3.37) in 2004 to 1.15% (95% CI, 0.89–1.41) in 2008 (p 0.001). The age specific prevalence per total number of reactive VDRL/RPR was highest amongst pregnant women aged 26 to 30 years (p 0.001) and lowest for those aged 16 to 20 years (p 0.025) during the period 2004–2008. However, there were variations in syphilis prevalence rates within and between the clinics.Conclusion: Syphilis sero-positivity in pregnancy in Gaborone, Botswana has been declining for the last five years, but was more prevalent amongst pregnant women aged 26 to 30 years with the lowest prevalence among those aged 16 to 20 years during the period 2004 to 2008. This decline may be attributed to a number of factors and, in particular, the adoption of the syndromic approach for management of sexually transmitted infections in the country.

Exploring the molecular mechanisms of parasite-host interactions with a view towards new therapeutics and vaccines

Despite the massive disease burden worldwide caused by parasitic nematodes and other infectious pathogens, the molecular basis of many infectious diseases caused by these pathogens has been unduly neglected for a long time. Therefore, accelerated progress towards novel therapeutics, and ultimately control of such infectious diseases, is of crucial importance. Capitalising on the wealth of data becoming available from proteomic and genomic studies, new protein targets at the pathogen-host interface can be identified and subjected to protein-based explorations of the molecular basis of pathogen-host interactions. By combining the use of systems and structural biology methodologies, insights into the structural and molecular mechanisms of these interactions can assist in the development of therapeutics and/or vaccines. This brief review examines two different proteins from the body wall of blood flukes - annexins and the stress-induced phosphoprotein 1 - both of which are presently interesting targets for the development of therapeutics.

A practical Java tool for small-molecule compound appraisal

BACKGROUND

The increased use of small-molecule compound screening by new users from a variety of different academic backgrounds calls for adequate software to administer, appraise, analyse and exchange information obtained from screening experiments. While software and spreadsheet solutions exist, there is a need for software that can be easily deployed and is convenient to use.

RESULTS

The Java application cApp addresses this need and aids in the handling and storage of information on small-molecule compounds. The software is intended for the appraisal of compounds with respect to their physico-chemical properties, analysis in relation to adherence to likeness rules as well as recognition of pan-assay interference components and cross-linking with identical entries in the PubChem Compound Database. Results are displayed in a tabular form in a graphical interface, but can also be written in an HTML or PDF format. The output of data in ASCII format allows for further processing of data using other suitable programs. Other features include similarity searches against user-provided compound libraries and the PubChem Compound Database, as well as compound clustering based on a MaxMin algorithm.

CONCLUSIONS

cApp is a personal database solution for small-molecule compounds which can handle all major chemical formats. Being a standalone software, it has no other dependency than the Java virtual machine and is thus conveniently deployed. It streamlines the analysis of molecules with respect to physico-chemical properties and drug discovery criteria; cApp is distributed under the GNU Affero General Public License version 3 and available from http://www.structuralchemistry.org/pcsb/. To download cApp, users will be asked for their name, institution and email address. A detailed manual can also be downloaded from this site, and online tutorials are available at http://www.structuralchemistry.org/pcsb/capp.php.

Chemical probing suggests redox-regulation of the carbonic anhydrase activity of mycobacterial Rv1284

The mycobacterial enzyme Rv1284 is a member of the β-carbonic anhydrase family that is considered essential for survival of the pathogen. The active site cavity of this dimeric protein is characterized by an exceptionally small volume and harbours a catalytic zinc ion coordinated by two cysteine and one histidine residue side chains. Using the natural products polycarpine and emodin as chemical probes in crystallographic experiments and stopped-flow enzyme assays, we report that the catalytic activity can be reversibly inhibited by oxidation. Oxidative conditions lead to the removal of one of the active site cysteine residues from the coordination sphere of the catalytic metal ion by engagement in a disulfide bond with another cysteine residue close by. The subsequent loss of the metal ion, which is supported by crystallographic analysis, may thus render the protein catalytically inactive. The oxidative inhibition of Rv1284 can be reversed by exposing the protein to reducing conditions. Because the physical size of the chemical probes used in the present study substantially exceeds the active site volume, we hypothesized that these compounds exert their effects from a surface-bound location and identified Tyr120 as a critical residue for oxidative inactivation. These findings link conditions of oxidative stress to pH homeostasis of the pathogen. Because oxidative stress and acidification are defence mechanisms employed by the innate immune system of the host, we suggest that Rv1284 may be a component of the mycobacterial survival strategy.

DATABASE

Atomic coordinates and structure factors have been deposited in the Protein Data Bank under accession numbers 4yf4, 4yf5 and 4yf6.

Lateral ankle and hindfoot instability: a new clinical based classification

Ankle sprains are one of the most common soft tissue injuries accounting for nearly 40% of sports injuries. There are large number of procedures for its treatment reported in the literature with largely good results. The ankle forms a functional unit with the subtalar joint. We present a new classification for peritalar lateral instability. There are two intents of this classification. Firstly, the classification demonstrates an assessment and treatment guideline for the many causes of peritalar lateral instability. The second use of the classification is for research purposes so that cohorts of patients can be accurately described and the efficacy of different operations in different groups can be properly assessed.

Comparison of VILIP-1 and VILIP-3 binding to phospholipid monolayers

The neuronal calcium sensor proteins Visinin-like Proteins 1 (VILIP-1) and 3 (VILIP-3) are effectors of guanylyl cyclase and acetyl choline receptors, and transduce calcium signals in the brain. The “calcium-myristoyl” switch, which involves a post-translationally added myristoyl moiety and calcium binding, is thought to regulate their membrane binding capacity and therefore, play a critical role in their mechanism of action. In the present study, we investigated the effect of membrane composition and solvent conditions on the membrane binding mechanisms of both VILIPs using lipid monolayers at the air/buffer interface. Results based on comparison of the adsorption kinetics of the myristoylated and non-myristoylated proteins confirm the pivotal role of calcium and the exposed myristol moiety for sustaining the membrane-bound state of both VILIPs. However, we also observed binding of both VILIP proteins in the absence of calcium and/or myristoyl conjugation. We propose a two-stage membrane binding mechanism for VILIP-1 and VILIP-3 whereby the proteins are initially attracted to the membrane surface by electrostatic interactions and possibly by specific interactions with highly negatively charged lipids head groups. The extrusion of the conjugated myristoyl group, and the subsequent anchoring in the membrane constitutes the second stage of the binding mechanism, and ensures the sustained membrane-bound form of these proteins.

Probing the equatorial groove of the hookworm protein and vaccine candidate antigen, Na-ASP-2

Hookworm activation-associated secreted proteins can be structurally classified into at least three different groups. The hallmark feature of Group 1 activation-associated secreted proteins is a prominent equatorial groove, which is inferred to form a ligand binding site. Furthermore, a conserved tandem histidine motif is located in the centre of the groove and believed to provide or support a yet to be determined catalytic activity. Here, we report three-dimensional crystal structures of Na-ASP-2, an L3-secreted activation-associated secreted protein from the human hookworm Necator americanus, which demonstrate transition metal binding ability of the conserved tandem histidine motif. We further identified moderate phosphohydrolase activity of recombinant Na-ASP-2, which relates to the tandem histidine motif. By panning a random 12-mer peptide phage library, we identified a peptide with high similarity to the human calcium-activated potassium channel SK3, and confirm binding of the synthetic peptide to recombinant Na-ASP-2 by differential scanning fluorimetry. Potential binding modes of the peptide to Na-ASP-2 were studied by molecular dynamics simulations which clearly identify a preferred topology of the Na-ASP-2:SK3 peptide complex.

Crystal structure and immunological properties of the first annexin from Schistosoma mansoni: insights into the structural integrity of the schistosomal tegument

Schistosomiasis is a major parasitic disease of humans, second only to malaria in its global impact. The disease is caused by digenean trematodes that infest the vasculature of their human hosts. These flukes are limited externally by a body wall composed of a syncytial epithelium, the apical surface membrane of which is a parasitism-adapted dual membrane complex. Annexins are thought to be of integral importance for the stability of this apical membrane system. Here, we present the first structural and immunobiochemical characterization of an annexin from Schistosoma mansoni. The crystal structure of annexin B22 confirms the presence of the previously predicted α-helical segment in the II/III linker and reveals a covalently linked head-to-head dimer. From the calcium-bound crystal structure of this protein, canonical type II, type III and B site positions are occupied, and a novel binding site has been identified. The dimer arrangement observed in the crystal structure suggests the presence of two prominent features, a potential non-canonical membrane binding site and a potential binding groove opposite to the former. Results from transcriptional profiling during development show that annexin B22 expression is correlated with life stages of the parasite that possess the syncytial tegument layer, and ultrastructural localization by immuno-electron microscopy confirms the occurrence of annexins in the tegument of S. mansoni. Data from membrane binding and aggregation assays indicate the presence of differential molecular mechanisms and support the hypothesis of annexin B22 providing structural integrity in the tegument.

Non-classical β-carbonic anhydrase inhibitors-towards novel anti-mycobacterials

Mycobacterial carbonic anhydrases, such as the essential protein Rv3588c, are attractive drug targets since they constitute a different class of carbonic anhydrases than those found in humans.

The Relevance of Structural Biology in Studying Molecules Involved in Parasite–Host Interactions: Potential for Designing New Interventions

New interventions against infectious diseases require a detailed knowledge and understanding of pathogen–host interactions and pathogeneses at the molecular level. The combination of the considerable advances in systems biology research with methods to explore the structural biology of molecules is poised to provide new insights into these areas. Importantly, exploring three-dimensional structures of proteins is central to understanding disease processes, and establishing structure–function relationships assists in identification and assessment of new drug and vaccine targets. Frequently, the molecular arsenal deployed by invading pathogens, and in particular parasites, reveals a common theme whereby families of proteins with conserved three-dimensional folds play crucial roles in infectious processes, but individual members of such families show high levels of specialisation, which is often achieved through grafting particular structural features onto the shared overall fold. Accordingly, the applicability of predictive methodologies based on the primary structure of proteins or genome annotations is limited, particularly when thorough knowledge of molecular-level mechanisms is required. Such instances exemplify the need for experimental three-dimensional structures provided by protein crystallography, which remain an essential component of this area of research. In the present article, we review two examples of key protein families recently investigated in our laboratories, which could represent intervention targets in the metabolome or secretome of parasites.

A genome-wide analysis of annexins from parasitic organisms and their vectors

In this study, we conduct an in-depth analysis of annexin proteins from a diverse range of invertebrate taxa, including the major groups that contain the parasites and vector organisms that are harmful to humans and domestic animals. Using structure-based amino acid sequence alignments and phylogenetic analyses, we present a classification for this protein group and assign names to sequences with ambiguous annotations in public databases. Our analyses reveal six distinct annexin clades, and the mapping of genes encoding annexins to the genome of the human blood fluke Schistosoma mansoni supports the hypothesis of gene duplication as a major evolutionary event in annexin genesis. This study illuminates annexin diversity from a novel perspective using contemporary phylogenetic hypotheses of eukaryote evolution, and will aid the consolidation of annexin protein identities in public databases and provide a foundation for future functional analysis and characterisation of these proteins in parasites of socioeconomic importance.

Anaesthetic management of the child with co-existing pulmonary disease

Children with co-existing pulmonary disease have a wide range of clinical manifestations with significant implications for anaesthetists. Although there are a number of pulmonary diseases in children, this review focuses on two of the most common pulmonary disorders, asthma and bronchopulmonary dysplasia (BPD). These diseases share the physiology of bronchoconstriction and variably decreased flow in the airways, but also have unique physiological consequences. The anaesthetist can make a difference in outcomes with proper preoperative evaluation and appropriate preparation for surgery in the context of a team approach to perioperative care with implementation of a stepwise approach to disease management. An understanding of the importance of minimizing the risk for bronchoconstriction and having the tools at hand to treat it when necessary is paramount in the care of these patients. Unique challenges exist in the management of pulmonary hypertension in BPD patients. This review covers medical treatment, intraoperative management, and postoperative care for both patient populations.

Alpha-1 giardin is an annexin with highly unusual calcium-regulated mechanisms

Alpha-giardins constitute the annexin proteome (group E annexins) in the intestinal protozoan parasite Giardia and, as such, represent the evolutionary oldest eukaryotic annexins. The dominance of alpha-giardins in the cytoskeleton of Giardia with its greatly reduced actin content emphasises the importance of the alpha-giardins for the structural integrity of the parasite, which is particularly critical in the transformation stage between cyst and trophozoite. In this study, we report the crystal structures of the apo- and calcium-bound forms of α1-giardin, a protein localised to the plasma membrane of Giardia trophozoites that has recently been identified as a vaccine target. The calcium-bound crystal structure of α1-giardin revealed the presence of a type III site in the first repeat as known from other annexin structures, as well as a novel calcium binding site situated between repeats I and IV. By means of comparison, the crystal structures of three different alpha-giardins known to date indicate that these proteins engage different calcium coordination schemes, among each other, as well as compared to annexins of groups A-D. Evaluation of the calcium-dependent binding to acidic phosphoplipid membranes revealed that this process is not only mediated but also regulated by the environmental calcium concentration. Uniquely within the large family of annexins, α1-giardin disengages from the phospholipid membrane at high calcium concentrations possibly due to formation of a dimeric species. The observed behaviour is in line with changing calcium levels experienced by the parasite during excystation and may thus provide first insights into the molecular mechanisms underpinning the transformation and survival of the parasite in the host.

PP087. Deep trial secondary analysis: Digoxin immune fab fragment treatment has additional benefits in endogenous digitalis-like factor positive preeclamptic women

INTRODUCTION

A double blinded placebo controlled clinical trial of a commercial digoxin immune Fab fragment (DIF) in preeclamptic (PE) women provided some benefit to treated subjects (1). In that study DIF, relative to placebo, prevented a decline in CrCl and lowered levels of endogenous digitalis-like factor (EDLF) activity as measured by sodium pump inhibition (SPI). However, some PE subjects had undetectable EDLF.

OBJECTIVES

The hypothesis tested was that only PE women with measureable EDLF would respond to DIF treatment and analysis of EDLF positive women might reveal treatment effects masked by inclusion of EDLF negative, and hence non-responding, PE women. Accordingly, analyses of DIF effects in EDLF positive PE women were conducted.

METHODS

Patient characteristics and study design have been published (1). In these subanalyses, subjects were considered to be EDLF positive if their plasma inhibited red cell sodium pump mediated Rb uptake. All analyses were redone for the EDLF positive subgroup by Covance Inc as in the original trial. Continuous data were analyzed by ANCOVA. Categorical data were analyzed by Barnard Exact Test.

RESULTS

45 subjects (23 DIF, 22 placebo) had baseline SPI evaluated. Of these 22% had undetectable SPI. EDLF positive PE women showed greater and more significant reductions of SPI in response to DIF at each time point (12, 24, 48 hr treatment) than in the original analysis. Subjects with undetectable EDLF showed no significant change in response to DIF or placebo. For CrCl, EDLF positive PE women showed greater and more significant preservation of CrCl compared with original analyses. Subjects absent EDLF showed deterioration of CrCl with or without DIF. Among EDLF positive PE women DIF treated women had significantly less maternal pulmonary edema (p=0.035) and significantly less intraventricular hemorrhage in their infants (p=0.015). There was the suggestion of reductions in the incidence of other maternal and neonatal abnormalities.

CONCLUSION

These data indicate that EDLF positive PE women are those that responded to DIF and also raise the possibility of extended benefits of DIF treatment in this group. Results support further research in this area.

Intraoperative cell salvage versus postoperative autologous blood transfusion in hip arthroplasty: a retrospective service evaluation

INTRODUCTION

A number of ways of reducing blood loss in arthroplasty have been explored, including preoperative autologous transfusion, intraoperative cell salvage and postoperative autologous transfusions. Both intraoperative blood salvage and postoperative retransfusion drains have been shown to be effective in reducing blood loss in total hip arthroplasty. In our department there was a change in practice from using postoperative retransfusion drains to intraoperative cell salvage. To our knowledge no study has directly compared using intraoperative blood salvage and postoperative retransfusion drains alone in total hip arthroplasty.

METHODS

This was a retrospective service evaluation including all primary hip arthroplasty performed under our care between January 2006 and December 2008. Patients were divided into two groups: Group A used a postoperative autologous blood transfusion (ABT) drain and Group B used intraoperative cell salvage.

RESULTS

A total of 144 patients were included in this study: 84 in Group A and 60 in Group B. The mean haemoglobin difference for Group A was 3.96g/dl (standard deviation [SD]: 1.52) and for Group B it was 3.46g/dl (SD: 1.42). The mean haematocrit difference for Group A was 0.12% (SD: 0.05) and for Group B it was 0.10% (SD: 0.04). Using an independent t-test for the comparison of means, a significant difference was found between Group A and B both in regards to haemoglobin difference (p=0.009) and haematocrit difference (p=0.046).

CONCLUSIONS

We feel that intraoperative cell salvage provides a more efficient method of reducing blood loss than postoperative retransfusion in primary total hip replacement. A prospective randomised study would be useful to ascertain any clinical difference between the two methods.

FIZZ1 potentiates the carbachol-induced tracheal smooth muscle contraction

FIZZ1 is an adipokine highly expressed under inflammatory conditions, and yet, little is known of its function. In this study we examine the expression and function of FIZZ1 in an ovalbumin mouse model of asthma. Trachea from naïve or ovalbumin-sensitised and -challenged mice were compared for transcriptional, functional and proteomic differences using gene microarrays, ex vivo tracheal contraction, immunohistochemistry and Western blot analysis. FIZZ1 was expressed in ovalbumin-treated, but not naïve, trachea. Naïve trachea incubated with recombinant FIZZ1 exhibited denuded epithelium and contractile hyperresponsiveness. The FIZZ1-incubated trachea also exhibited an associated increased expression of phospho-c-Raf, phospho-extracellular signal-regulated kinase 1/2, phospho-p38, MLCK and MLC-20. These data demonstrate that FIZZ1 regulates tracheal smooth muscle contraction through impairment of the epithelium and activation of the mitogen-activated protein kinase pathway in muscle.

PCA3: A urine-based genetic assay for detection of prostate cancer in men with elevated PSA

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Background: Currently, early detection of prostate cancer relies primarily on an abnormal digital rectal examination (DRE) and an elevated prostate-specific antigen (PSA) level leading to a prostate biopsy. However, because of low positive predictive values, up to 75% of men with elevated PSA and/or suspicious DRE have a negative biopsy. We investigated the value of a new molecular marker–PCA3 in predicting the likelihood of prostate cancer. Methods: We undertook a prospective, multi-practice, community-urologist-based, and IRB approved clinical trial to evaluate PCA3. Urine samples were obtained from 974 men with elevated serum PSA (> 2.5ng/ml) and/or abnormal digital rectal examination prior to routine minimum 10-core prostate biopsy following standard study protocol in 30 medical practices. Urine samples were processed within 48 hours of collection. PCA3 and PSA mRNA were isolated, amplified and quantified by magnetic target capture, transcription-mediated amplification, and chemiluminescent hybridization protection assay technologies. The PCA3 value was determined using the ratio of PCA3 mRNA copy number to the PSA mRNA copy number multiplied by 1,000. Results: In total, 380 of 974 patients (39%) were diagnosed with prostate cancer, with a mean Gleason score of 7 (range, 6–9) and 26% (range 1–100%) of the biopsy specimens involved by cancer. An additional 106 cases (11%) had only high-grade PIN and/or atypical small acinar proliferation suspicious for cancer (ASAP), and 488 cases (50%) were benign. The mean PCA3 value in men with prostate cancer was significantly higher than in those without cancer (48 vs. 26, p < 0.0001). PCA3 score was associated with the presence of cancer (p < 0.0001) and Gleason score (p = 0.0001), but was not associated cancer volume (p = 0.56). Using a cutoff value of 35, PCA3 had an odds ratio of 2.6 for predicting prostate cancer. PCA3 had a specificity of 77% and a sensitivity of 44% for the diagnosis of prostate cancer, while the specificity and sensitivity for serum PSA were 22% and 87%, respectively. Conclusions: We found that the PCA3 urine test significantly improved the specificity for the detection of prostate cancer compared to serum PSA. Further evaluation of this urinary marker in screening for prostate cancer appears indicated.

No significant financial relationships to disclose.

Digibind attenuates cytokine TNFalpha-induced endothelial inflammatory response: potential benefit role of digibind in preeclampsia

OBJECTIVE

Exaggerated inflammatory response occurs in preeclampsia. Preeclampsia is also associated with elevated endogenous digoxin-like factors (EDLFs). Clinical data suggest that Digibind (a polyclonal sheep digoxin binding Fab fragment) binds to EDLF and may have the potential to attenuate vasoconstriction and other clinical symptoms of preeclampsia. This study was undertaken to determine if Digibind could attenuate increased endothelial inflammatory response induced by tumor necrosis factor-alpha (TNFalpha).

STUDY DESIGN

Confluent endothelial cells were treated with TNFalpha at different concentrations with or without Digibind in culture. Endothelial adhesion molecule ICAM, VCAM and E-selectin expressions were determined by an immunoassay directly detected on the endothelial surface. Effects of Digibind on TNFalpha-induced extracellular signal-regulated kinase and Na(+)/K(+)-ATPase expressions were also examined.

RESULT

(1) TNFalpha induced dose-dependent increases in ICAM, VCAM and E-selectin expressions in endothelial cells; (2) Digibind could attenuate and reduce TNFalpha-induced upregulation of endothelial E-selectin, ICAM and VCAM expressions. The blocking effect was in a concentration dependent manner; (3) Digibind had no effects on TNFalpha-induced upregulation of extracellular signal-regulated kinase phosphorylation, but could block TNFalpha-induced downregulation of Na(+)/K(+)-ATPase beta1 expression.

CONCLUSION

Digibind may exert beneficial effects by preserving cell membrane Na(+)/K(+)-ATPase function and consequently to offset increased inflammatory response in endothelial cells.

Single dose oral naproxen and naproxen sodium for acute postoperative pain

BACKGROUND

Postoperative pain is often poorly managed. Treatment options include a range of drug therapies such as non-steroidal anti-inflammatory drugs (NSAIDs) of which naproxen is one. Naproxen is used to treat a variety of painful conditions including acute postoperative pain, and is often combined with sodium to improve its solubility for oral administration. Naproxen sodium 550 mg (equivalent to 500 mg of naproxen) is considered to be an effective dose for treating postoperative pain but to date no systematic review of the effectiveness of naproxen/naproxen sodium at different doses has been published.

OBJECTIVES

To assess the efficacy, safety and duration of action of a single oral dose of naproxen or naproxen sodium for acute postoperative pain in adults.

SEARCH STRATEGY

We searched The Cochrane Library, MEDLINE, EMBASE and the Oxford Pain Relief Database for relevant studies. Additional studies were identified from the reference list of retrieved reports. The most recent search was undertaken in July 2004.

SELECTION CRITERIA

Included studies were randomised, double blind, placebo-controlled trials of a single dose of orally administered naproxen or naproxen sodium in adults with moderate to severe acute postoperative pain.

DATA COLLECTION AND ANALYSIS

Pain relief or pain intensity data were extracted and converted into dichotomous information to give the number of patients with at least 50% pain relief over four to six hours. Relative risk estimates (RR) and the number-needed-to-treat (NNT) for at least 50% pain relief were then calculated. Information was sought on the percentage of patients experiencing any adverse event, and the number-needed-to-harm was derived. Time to remedication was also estimated.

MAIN RESULTS

Ten trials (996 patients) met the inclusion criteria: nine assessed naproxen sodium; one combined the results from two small trials of naproxen alone. Included studies scored well for methodological quality. Meta-analysis of six trials (500 patients) that compared naproxen sodium 550 mg with placebo gave a RR for at least 50% pain relief over 4 to 6 hours of 4.2 (95% confidence interval (CI) 2.9 to 6.0) and an NNT of 2.6 (95% CI 2.2 to 3.2). Three trials (334 patients) assessed naproxen 400 mg and naproxen sodium 440 mg, giving a RR of 4.8 (95% CI 2.75 to 8.38). Two small studies indicated that naproxen 200 mg and naproxen sodium 220 mg may provide effective postoperative pain relief. There was no significant difference between the number of patients experiencing any adverse event on treatment compared with placebo. Weighted mean time to remedication for naproxen sodium 550 mg was 7.6 hours compared with 2.6 hours for placebo.

REVIEWERS' CONCLUSIONS

Naproxen sodium 550 mg, naproxen 400 mg and naproxen sodium 440 mg administered orally are effective analgesics for the treatment of acute postoperative pain in adults. A low incidence of adverse events was found but reporting was not consistent.

Women's reluctance to seek help for stress incontinence during pregnancy and following childbirth

OBJECTIVE

to identify whether women were made aware of stress incontinence around the time of childbirth, whether symptomatic women sought help from professionals caring for them at this time, to look at what help they receive in the first instance and to understand why some of those experiencing it chose not to seek help.

DESIGN

a qualitative survey was conducted using semi-structured interviews.

SETTING

interviews were conducted in participants' own homes.

PARTICIPANTS

42 women who reported symptoms of stress incontinence at eight weeks postpartum, and 15 women who were symptomatic one year following the birth of their baby.

FINDINGS

women were reluctant to seek help, although they were often inconvenienced and troubled by the condition. This was predominantly due to the nature of the condition itself, although the relationship with their health care professionals was also a consideration in some cases. The majority of women were not provided with information on the condition but wanted health professionals to provide a warning that the condition could occur. They also wanted health professionals to seek out information about symptoms, rather than the women themselves having to broach the subject. The first line of treatment at this time was usually a recommendation to perform pelvic floor exercises.

IMPLICATIONS FOR PRACTICE

health professionals caring for women during pregnancy or following the birth of their baby need to raise awareness of the condition, the treatment available, and to be pro-active in seeking out those experiencing incontinence rather than expecting women to approach them for help.

Factors associated with intended staff turnover and job search behaviour in services for people with intellectual disability

Staff turnover is a major problem in services for people with intellectual disability (ID). Therefore, understanding the reasons for staff turnover is vital for organizations seeking to improve their performance. The present study investigates the factors directly and indirectly associated with an intention to leave an organization and actual job search behaviour amongst staff in services for people with ID. As part of a large-scale survey of staff in services for people with ID, information was collected from 450 staff concerning intended turnover, job search behaviour and a wide range of factors potentially associated with these outcomes. Path analyses revealed that work satisfaction, job strain, younger staff age and easier subjective labour conditions were directly associated with intended turnover. The same factors, with the exception of younger staff age, were also directly associated with job search behaviour. Factors indirectly associated with these outcomes included wishful thinking, alienative commitment to the organization, lack of staff support, role ambiguity, working longer contracted hours, having a low-status job, a lack of influence over decisions at work and less orientation to working in community settings with people with ID. The models of staff turnover empirically derived in the present study confirm and extend previous research in this area. The implications for organizations are discussed.

The instruction in pelvic floor exercises provided to women during pregnancy or following delivery

OBJECTIVES

to examine the instruction in pelvic floor exercises given to women during pregnancy or following delivery, to assess the quality of any instruction provided, and to consider these in light of the women's views about the service.

DESIGN

a postal questionnaire was sent to a sample of women when they reached 34 weeks of pregnancy and a second at 8 weeks postpartum. A sub-sample of women who reported symptoms of stress incontinence at 8 weeks postpartum were interviewed about the instruction in pelvic floor exercises that they received during their pregnancy, or in the puerperium.

PARTICIPANTS

of the 918 women who were sent the first questionnaire, 717 returned it completed (78%). Five-hundred-and-seventy-two of 894 women (64%) completed the second questionnaire. Forty-two of 179 symptomatic women (23%) took part in an interview.

FINDINGS

55% of women received some form of instruction in pelvic floor exercises by 34 weeks of pregnancy. Eighty-six percent received instruction following birth. The way the information was given varied, ranging from a brief reminder, to exercising in a class with an instructor. The information was provided by a range of health professionals, and no single profession appeared to undertake responsibility for the service. As a result, the views of the service varied. A few women reported that they had received good quality instruction, others were critical of it, and a small number reported that they had received no instruction at all. The widespread practice of leaving a leaflet by the women's beds during their stay in hospital, was criticised by a large proportion of the women.

KEY CONCLUSION

the instruction in pelvic floor exercises by health service professionals was provided on an ad hoc basis. In many instances, the programme of instruction did not meet recommendations made in the literature. It is likely that the success of randomised controlled trials reported in the literature would not be repeated in the 'real world' Implications for practice: there is a need for the service to be reorganised so that all women receive high-quality instruction during pregnancy, with a reminder to exercise following birth. This could help to prevent, or relieve, the symptoms of stress incontinence that frequently occur at these times.

Predicting the persistence of severe self-injurious behavior

Information was collected on 95 people with mental retardation who had been identified seven years previously as showing severe self-injurious behavior. At follow up 71% of participants were still showing self-injurious behavior of a severity which presented a management problem for care staff. The occurrence of specific topographies of self-injury was extremely stable among the group showing persistent self-injury. Finally, self-injury status at follow-up was predicted with 76% accuracy by a logistic regression model containing three variables: site of injury (higher persistence being shown by people exhibiting head directed self-injury); reported (greater) stability of self-injury when first identified; and (younger) age.

The prevalence of challenging behaviors: a total population study

A total population study was undertaken in two areas of England to identify the situation and characteristics of people reported to exhibit challenging behaviors. We found that: (1) challenging behaviors are shown by 10-15% of people with mental retardation who are in contact with educational, health or social care services for people with mental retardation; (2) the most common forms of challenging behaviors reported were 'other' behavior (shown by 9%-12% of all people screened), aggression (7%), destructive behavior (4%-5%) and self-injury (4%); (3) the majority of people identified showed two or more of these four general forms of challenging behavior; (4) approximately two-thirds of the people identified were boys/men; (5) close to two-thirds of the people identified were adolescents or young adults; (6) approximately 50% of the people identified as showing more demanding challenging behavior were living with their families; (7) people who showed more demanding challenging behavior were more likely to need greater levels of assistance in eating, dressing and washing, be incontinent and have more restricted expressive and receptive communication.

Body language--non-verbal cues

Interviews for employment are significant events in peoples lives. Preparing for one and getting through it can be a memorable experience, good or bad. We all know that what we don't say can be as important as what we do say. In this fascinating piece of research Lesley Mason describes how she was able to relate the non-verbal communication of interview candidates to the outcome of the interview. Read on and find out what you were really saying as you sat, squirmed or twiddled your way through that last interview....

Defining mechanisms of action of interleukin-11 on the progression of radiation-induced oral mucositis in hamsters

Oral ulcerative mucositis is a common toxicity associated with drug and radiation therapy for cancer. It impacts on quality of life and economic outcomes, as well as morbidity and mortality. Mucositis is often associated with dose limitations for chemotherapy or is a cause for dose interruption for radiation. The complexity of mucositis as a biological process has only been recently appreciated. It has been suggested that the condition represents a sequential interaction of oral mucosal cells and tissues, pro-inflammatory cytokines and local factors such as saliva and the oral microbiota. The recognition that the pathophysiology of mucositis is a multifactorial process was partially suggested by the observation that interleukin-11 (IL-11), a pleotropic cytokine, favorably altered the course of chemotherapy-induced mucositis in an animal model. In the current study, we evaluated a series of biologic and morphologic outcomes to determine their roles and sequence in the development of experimental radiation-induced mucositis and to evaluate the effects of IL-11 in attenuating them. Our results suggest that IL-11 favorably modulates acute radiation-induced mucositis by attenuating pro-inflammatory cytokine expression. Data are also presented which help define the pathobiological sequence of mucositis.