From affinity selection to kinetic selection in Germinal Centre modelling.

Affinity maturation is an evolutionary process by which the affinity of antibodies (Abs) against specific antigens (Ags) increases through rounds of B-cell proliferation, somatic hypermutation, and positive selection in germinal centres (GC). The positive selection of B cells depends on affinity, but the underlying mechanisms of affinity discrimination and affinity-based selection are not well understood. It has been suggested that selection in GC depends on both rapid binding of B-cell receptors (BcRs) to Ags which is kinetically favourable and tight binding of BcRs to Ags, which is thermodynamically favourable; however, it has not been shown whether a selection bias for kinetic properties is present in the GC. To investigate the GC selection bias towards rapid and tight binding, we developed an agent-based model of GC and compared the evolution of founder B cells with initially identical low affinities but with different association/dissociation rates for Ag presented by follicular dendritic cells in three Ag collection mechanisms. We compared an Ag collection mechanism based on association/dissociation rates of B-cell interaction with presented Ag, which includes a probabilistic rupture of bonds between the B-cell and Ag (Scenario-1) with a reference scenario based on an affinity-based Ag collection mechanism (Scenario-0). Simulations showed that the mechanism of Ag collection affects the GC dynamics and the GC outputs concerning fast/slow (un)binding of B cells to FDC-presented Ags. In particular, clones with lower dissociation rates outcompete clones with higher association rates in Scenario-1, while remaining B cells from clones with higher association rates reach higher affinities. Accordingly, plasma cell and memory B cell populations were biased towards B-cell clones with lower dissociation rates. Without such probabilistic ruptures during the Ag extraction process (Scenario-2), the selective advantage for clones with very low dissociation rates diminished, and the affinity maturation level of all clones decreased to the reference level.

A self-portrait: Design opportunities for a tool that supports children's involvement in brain-related health care.

INTRODUCTION: Paediatric patients with disorders that involve brain functioning are particularly vulnerable with respect to including them in shared decision-making. Current tools are mostly paper or digital patient information. We lay the groundwork for improving engagement with a concept that we coined 'the Self-Portrait'. The main goals were to identify (1) obstacles and (2) design parameters that enable patient participation. METHODS: A research-through-design approach was utilized in nine patients with brain-related disorders (4-12 years), 15 parents and 15 medical professionals, involving contextual research (interviews and observations) within the paediatric hospital and patients' homes and codesign. Sensitizing materials and early instances of design solutions were deployed as catalysts for communication. Five rounds of enriched interviews and design reviews were thematically analysed to answer the research questions. RESULTS: Obstacles to child involvement were related to children's level of understanding, the time and energy necessary for information processing and lack of perceived relevance of the information. Patients' engagement is supported by design features that extend the time frame of interaction beyond the consultation, transfer information interactively and give control and influence during the consultation. CONCLUSION: Obstacles were detected that complicate child engagement, which differ between stakeholders. Promising design features were identified that have the potential to play an important role in enabling active child involvement. These findings show that applying principles of human-centred design research and codesign can bring together patients, parents and medical professionals around a tool that provides a shared language and focus, which are prerequisites to increase child engagement. PATIENT OR PUBLIC CONTRIBUTION: Patients, parents and clinicians contributed as design informants during contextual research and design reviews. Clinicians provided feedback on the initial outcomes of thematic analysis. Two researchers assisted in consensus sessions during the thematic analysis.

Atmospheric modeling and source reconstruction of radioactive ruthenium from an undeclared major release in 2017.

In October 2017 unusual 106Ru detections across most of Europe prompted the Institut de Radioprotection et de Sûreté Nucléaire (IRSN) to analyze the event in order to locate the origin and identify the magnitude of the release. This paper presents the inverse modeling techniques used during the event to achieve this goal. The method is based on a variational approach and consists of using air concentration measurements with the ldX long-range dispersion model included in the IRSN's C3X operational platform. The method made it possible to quickly identify the southern Urals as the most likely geographical origin of the release. Despite uncertainties regarding the starting date of the release, calculations show that it potentially began on 23 September, while most of the release was emitted on 26 September. Among the nuclear plants identified in the southern Urals, the Mayak complex is that from which the dispersion of the 106Ru plume is most consistent with observations. The reconstructed 106Ru source term from Mayak is ∼250 TBq. In total, it was found that for 72% of the measurements simulated and observed air concentration agreed within a factor of 5. In addition, the simulated deposition of 106Ru agrees with the observed deposition. Outside the southern Urals, the simulations indicate that areas with highest deposition values are located in southern Scandinavia and southeastern Bulgaria and are explained by rainfall events occurring while the plume was passing over.

Thermal tolerance of two Diptera that pollinate thermogenic plants.

Pollinating insects can be exposed to temperatures far from ambient air when visiting flowers, reducing their warming tolerance. Typically, such scenario occurs when flowers are exposed to solar radiation. The case of thermogenic flowers is particular because they warm up even when they are not exposed to solar energy. The flowers of Arum attract their pollinators with a deceptive method and trap them for a whole day, thereby imposing elevated temperature to visiting insects. Therefore, we predict a relatively high basal thermal tolerance in those insects. The aim of this study was to assess the thermal tolerance and warming tolerance of females of two fly species (genus Psychoda) pollinating Arum sp. (thermogenic plant). We measured their critical temperature (CTmax) and its response to rate of temperature increase as well as acclimation period to moderate temperature of 25 °C. We found relatively low CTmax (33.7 °C on average) for both species, and a weak response to acclimation period and ramping rate. In general, the thermal tolerance increased with a rapid ramping in temperature. To evaluate the warming tolerance, we compared thermal tolerance limits to flower temperatures measured in the field. We highlighted that the temperature of the thermogenic floral organ could reach values close to the thermal tolerance threshold of pollinators. This discovery raises questions about the sustainability of the interaction between these thermogenic plants and their pollinators.

Applying an Oleophobic/Hydrophobic Fluorinated Polymer Monolayer Coating from Aqueous Solutions.

Despite major advancements in the fabrication of low-surface-energy surfaces, the environmental consequences of their fabrication can be a serious issue, particularly in an industrial context. This is especially the case for fluorine-based coatings, which often require fluorinated solvents for their processing and applications. These solvents are not only detrimental to the ozone layer but also represent a potential workplace hazard because they tend to bioaccumulate. We describe the design, synthesis, and characterization of a new fluorinated-polymer coating that can be simply applied to surfaces from an aqueous environment using a dip-coating technique. This was made possible by copolymerizing three different methacrylate monomers, each serving a specific function. Namely, fluorinated methacrylate providing oleo/hydrophobicity, photocleavable polyethylene glycol (PEG) methacrylate promoting water solubility of the copolymer, and thioether-based methacrylate serving as an anchoring unit to a number of different substrates. This copolymer is initially grafted to the surface as a monolayer from an aqueous solvent, after which the system is treated with ultraviolet (UV) light, cleaving away the protecting PEG moieties to yield an oleo/hydrophobic surface.

Sampling and Analysis in Flow: The Keys to Smarter, More Controllable, and Sustainable Fine-Chemical Manufacturing.

Process analytical technology (PAT) is a system designed to help chemists better understand and control manufacturing processes. PAT systems operate through the combination of analytical devices, reactor control elements, and mathematical models to ensure the quality of the final product through a quality by design (QbD) approach. The expansion of continuous manufacturing in the pharmaceutical and fine-chemical industry requires the development of PAT tools suitable for continuous operation in the environment of flow reactors. This requires innovative approaches to sampling and analysis from flowing media to maintain the integrity of the reactor content and the analyte of interest. The following Review discusses examples of PAT tools implemented in flow chemistry for the preparation of small organic molecules, and applications of self-optimization tools.

Peripheral nervous system involvement in systemic lupus erythematosus: a retrospective study on prevalence, associated factors and outcome.

BACKGROUND: Despite its potentially significant impact on disease outcome, peripheral nervous system involvement in systemic lupus erythematosus has received little attention. OBJECTIVE: The objective of this study was to assess the prevalence and clinical features of peripheral nervous system involvement in a large cohort of systemic lupus erythematosus patients. METHODS: The records of systemic lupus erythematosus patients examined at two tertiary referral centres over a period of 14 years (from 2000 to 2014) were analyzed. Peripheral nervous system events were ascertained according to the 1999 American College of Rheumatology case definitions and by using an attribution algorithm for neuropsychiatric events. Prevalence of peripheral nervous system in systemic lupus erythematosus and demographic, clinical and laboratory features were assessed. Patients with peripheral nervous system events were compared with a control group of systemic lupus erythematosus patients without peripheral nervous system involvement. RESULTS: In a retrospective cohort of 1224 patients, the overall prevalence of peripheral nervous system involvement was 6.9% (85 patients, 95% confidence interval 0.06-0.08), with 68% of peripheral nervous system events attributable to systemic lupus erythematosus. Polyneuropathy was the most common manifestation observed (38 events, 39.2%), followed by cranial neuropathy in 30 cases (30.9%) and 12 cases of single (12.4%) or multiple (eight events, 8.2%) mononeuritis. The average age of systemic lupus erythematosus onset was significantly higher in patients with peripheral nervous system events than in controls (mean ± standard deviation: 45.9 ± 14.8 vs. 37.1 ± 14.0) and they were more likely to have higher SLEDAI-2K and SLICC/ACR Damage Index scores, as well as hypertension and livedo reticularis. A subgroup analysis of events deemed to be systemic lupus erythematosus-related provided similar results. CONCLUSION: Peripheral nervous system manifestations are a potential complication of systemic lupus erythematosus. Careful neurological assessment should therefore be included in the diagnostic workup of patients with systemic lupus erythematosus, especially in those with later onset and greater damage and disease activity.

Gene expression polymorphism underpins evasion of host immunity in an asexual lineage of the Irish potato famine pathogen.

BACKGROUND: Outbreaks caused by asexual lineages of fungal and oomycete pathogens are a continuing threat to crops, wild animals and natural ecosystems (Fisher MC, Henk DA, Briggs CJ, Brownstein JS, Madoff LC, McCraw SL, Gurr SJ, Nature 484:186-194, 2012; Kupferschmidt K, Science 337:636-638, 2012). However, the mechanisms underlying genome evolution and phenotypic plasticity in asexual eukaryotic microbes remain poorly understood (Seidl MF, Thomma BP, BioEssays 36:335-345, 2014). Ever since the 19th century Irish famine, the oomycete Phytophthora infestans has caused recurrent outbreaks on potato and tomato crops that have been primarily caused by the successive rise and migration of pandemic asexual lineages (Goodwin SB, Cohen BA, Fry WE, Proc Natl Acad Sci USA 91:11591-11595, 1994; Yoshida K, Burbano HA, Krause J, Thines M, Weigel D, Kamoun S, PLoS Pathog 10:e1004028, 2014; Yoshida K, Schuenemann VJ, Cano LM, Pais M, Mishra B, Sharma R, Lanz C, Martin FN, Kamoun S, Krause J, et al. eLife 2:e00731, 2013; Cooke DEL, Cano LM, Raffaele S, Bain RA, Cooke LR, Etherington GJ, Deahl KL, Farrer RA, Gilroy EM, Goss EM, et al. PLoS Pathog 8:e1002940, 2012). However, the dynamics of genome evolution within these clonal lineages have not been determined. The objective of this study was to use a comparative genomics and transcriptomics approach to determine the molecular mechanisms that underpin phenotypic variation within a clonal lineage of P. infestans. RESULTS: Here, we reveal patterns of genomic and gene expression variation within a P. infestans asexual lineage by comparing strains belonging to the South American EC-1 clone that has dominated Andean populations since the 1990s (Yoshida K, Burbano HA, Krause J, Thines M, Weigel D, Kamoun S, PLoS Pathog 10e1004028, 2014; Yoshida K, Schuenemann VJ, Cano LM, Pais M, Mishra B, Sharma R, Lanz C, Martin FN, Kamoun S, Krause J, et al. eLife 2:e00731, 2013; Delgado RA, Monteros-Altamirano AR, Li Y, Visser RGF, van der Lee TAJ, Vosman B, Plant Pathol 62:1081-1088, 2013; Forbes GA, Escobar XC, Ayala CC, Revelo J, Ordonez ME, Fry BA, Doucett K, Fry WE, Phytopathology 87:375-380, 1997; Oyarzun PJ, Pozo A, Ordonez ME, Doucett K, Forbes GA, Phytopathology 88:265-271, 1998). We detected numerous examples of structural variation, nucleotide polymorphisms and loss of heterozygosity within the EC-1 clone. Remarkably, 17 genes are not expressed in one of the two EC-1 isolates despite apparent absence of sequence polymorphisms. Among these, silencing of an effector gene was associated with evasion of disease resistance conferred by a potato immune receptor. CONCLUSIONS: Our findings highlight the molecular changes underpinning the exceptional genetic and phenotypic plasticity associated with host adaptation in a pandemic clonal lineage of a eukaryotic plant pathogen. We observed that the asexual P. infestans lineage EC-1 can exhibit phenotypic plasticity in the absence of apparent genetic mutations resulting in virulence on a potato carrying the Rpi-vnt1.1 gene. Such variant alleles may be epialleles that arose through epigenetic changes in the underlying genes.

Thermoreversible hyaluronan-hydrogel and autologous nucleus pulposus cell delivery regenerates human intervertebral discs in an ex vivo, physiological organ culture model.

Numerous studies show promise for cell-based tissue engineering strategies aiming to repair painful intervertebral disc (IVD) degeneration. However, clinical translation to human IVD repair is slow. In the present study, the regenerative potential of an autologous nucleus pulposus (NP)-cell-seeded thermoresponsive hyaluronic acid hydrogel in human lumbar IVDs was assessed under physiological conditions. First, agarose-encased in vitro constructs were developed, showing greater than 90 % NP cell viability and high proteoglycan deposition within HA-pNIPAM hydrogels following 3 weeks of dynamic loading. Second, a bovine-induced IVD degeneration model was used to optimise and validate T1ρ magnetic resonance imaging (MRI) for detection of changes in proteoglycan content in isolated intact IVDs. Finally, isolated intact human lumbar IVDs were pre-scanned using the established MRI sequence. Then, IVDs were injected with HA-pNIPAM hydrogel alone or autologous NP-cell-seeded. Next, the treated IVDs were cultured under cyclic dynamic loading for 5 weeks. Post-treatment T1ρ values were significantly higher as compared to pre-treatment scans within the same IVD and region of interest. Histological evaluation of treated human IVDs showed that the implanted hydrogel alone accumulated proteoglycans, while those that contained NP cells also displayed neo-matrix-surrounded cells within the gel. The study indicated a clinical potential for repairing early degenerative human IVDs using autologous cells/hydrogel suspensions. This unique IVD culture set-up, combined with the long-term physiological culture of intact human IVDs, allowed for a more clinically relevant evaluation of human tissue repair and regeneration, which otherwise could not be replicated using the available in vitro and in vivo models.

CNTN6 mutations are risk factors for abnormal auditory sensory perception in autism spectrum disorders.

Contactin genes CNTN5 and CNTN6 code for neuronal cell adhesion molecules that promote neurite outgrowth in sensory-motor neuronal pathways. Mutations of CNTN5 and CNTN6 have previously been reported in individuals with autism spectrum disorders (ASDs), but very little is known on their prevalence and clinical impact. In this study, we identified CNTN5 and CNTN6 deleterious variants in individuals with ASD. Among the carriers, a girl with ASD and attention-deficit/hyperactivity disorder was carrying five copies of CNTN5. For CNTN6, both deletions (6/1534 ASD vs 1/8936 controls; P=0.00006) and private coding sequence variants (18/501 ASD vs 535/33480 controls; P=0.0005) were enriched in individuals with ASD. Among the rare CNTN6 variants, two deletions were transmitted by fathers diagnosed with ASD, one stop mutation CNTN6W923X was transmitted by a mother to her two sons with ASD and one variant CNTN6P770L was found de novo in a boy with ASD. Clinical investigations of the patients carrying CNTN5 or CNTN6 variants showed that they were hypersensitive to sounds (a condition called hyperacusis) and displayed changes in wave latency within the auditory pathway. These results reinforce the hypothesis of abnormal neuronal connectivity in the pathophysiology of ASD and shed new light on the genes that increase risk for abnormal sensory perception in ASD.

Musculoskeletal manifestations as determinants of quality of life impairment in patients with systemic lupus erythematosus.

Objective The objective of this study was to identify determinants of health-related quality of life (HRQoL) impairment in patients with systemic lupus erythematosus (SLE). Methods Overall, 101 SLE patients were recruited; 37 healthy subjects and 35 rheumatoid arthritis (RA) patients served as controls. HRQoL was evaluated using three patient reported outcomes (PROs): the Short Form-36 version 2 (SF-36v2) health survey, the fatigue scale version 4 (FACITv4) and the Heath Assessment Questionnaire (HAQ). A large set of demographic and clinical variables, including SLE arthritis subtypes, was evaluated searching for factors independently associated with worse QoL. Multivariate models were applied to identify factors independently associated with outcomes. Bonferroni's corrected p values < 0.05 were considered significant. Results SLE patients showed worse results than healthy controls ( p < 0.01) in all SF-36v2 domains and, with reference to the mental QoL, also than RA patients ( p < 0.01). Jaccoud's deformities, active arthritis, and fibromyalgia were the only factors independently associated with worse results in both physical and mental components summary of the SF-36v2 ( p < 0.01) and FACITv4 fatigue scale ( p < 0.01). Fragility fractures, deformities, and active arthritis negatively affected disability perception measured by the HAQ ( p < 0.01). No statistically significant differences in perceived HRQoL were highlighted between patients with deforming and erosive arthritis. However, they had significantly worse results than patients with non-deforming non-erosive arthritis across all investigated PROs ( p < 0.01). Conclusion In order to limit musculoskeletal manifestations as a source of impaired QoL in SLE patients, therapeutic strategies targeted to successfully manage active arthritis and fibromyalgia and to prevent deforming damage are needed.

Early Lupus Project: one-year follow-up of an Italian cohort of patients with systemic lupus erythematosus of recent onset.

Objective To describe the clinical and serological features of a prospectively followed cohort of early diagnosed systemic lupus erythematosus (SLE) patients during a one-year follow-up period. Methods SLE patients with disease duration less than 12 months were consecutively enrolled in a multicentre, prospective study. At study entry and then every 6 months, a large panel of data was recorded. Results Of 260 patients enrolled, 185 had at least 12 months of follow-up; of these, 84.3% were female, 92.4% were Caucasians. Mean diagnostic delay was about 20 months; higher values of European Consensus Lupus Activity Measurement (ECLAM) and of organs/systems involved were both associated with shorter diagnostic delay. Clinical and serological parameters improved after study entry. However, patients' quality of life deteriorated and cardiovascular risk factors significantly increased. About one-third of patients with active disease at study entry went into remission (ECLAM = 0). Negative predictors for remission were: oral ulcers, arthritis, low C4, anti-SSB (Ro) antibodies and therapy with mycophenolate. There was a widespread use of glucocorticoids both at baseline and during follow-up. Conclusion Clinical symptoms and serological parameters improve during the first period after diagnosis. However, patients' quality of life deteriorates. The widespread use of glucocorticoids is probably the reason for the early significant increase of some cardiovascular risk factors.

Triggered Metal Ion Release and Oxidation: Ferrocene as a Mechanophore in Polymers.

The introduction of mechanophores into polymers makes it possible to transduce mechanical forces into chemical reactions that can be used to impart functions such as self-healing, catalytic activity, and mechanochromic response. Here, an example of mechanically induced metal ion release from a polymer is reported. Ferrocene (Fc) was incorporated as an iron ion releasing mechanophore into poly(methyl acrylate)s (PMAs) and polyurethanes (PUs). Sonication triggered the preferential cleavage of the polymers at the Fc units over other bonds, as shown by a kinetic study of the molar mass distribution of the cleaved Fc-containing and Fc-free reference polymers. The released and oxidized iron ions can be detected with KSCN to generate the red-colored [Fe(SCN)n (H2 O)6-n )](3-n)+ complex or reacted with K4 [Fe(CN)6 ] to afford Prussian blue.

Quantitative Nano-characterization of Polymers Using Atomic Force Microscopy.

The present article offers an overview on the use of atomic force microscopy (AFM) to characterize the nanomechanical properties of polymers. AFM imaging reveals the conformations of polymer molecules at solid- liquid interfaces. In particular, for polyelectrolytes, the effect of ionic strength on the conformations of molecules can be studied. Examination of force versus extension profiles obtained using AFM-based single molecule force spectroscopy gives information on the entropic and enthalpic elasticities in pN to nN force range. In addition, single molecule force spectroscopy can be used to trigger chemical reactions and transitions at the molecular level when force-sensitive chemical units are embedded in a polymer backbone.

Demyelinating syndrome in SLE: review of different disease subtypes and report of a case series.

Demyelinating syndrome (DS) is a rare manifestation of systemic lupus erythematosus (SLE) (1%) with high clinical heterogeneity and potentially severe prognosis. It can represent a diagnostic and therapeutic challenge for clinicians. A recent study described 5 different patterns of demyelinating disease presentation, characterised by specific clinical, laboratory and brain and spine magnetic resonance imaging abnormalities: 1) neuromyelitis optica; 2) neuromyelitis optica spectrum disorders; 3) DS prevalently involving the brain; 4) DS prevalently involving the brainstem; 5) clinically isolated syndrome. In this review we briefly discuss typical characteristics of each DS presentation in SLE and we describe 5 illustrative clinical cases, one for each subset of DS, considering both diagnostic and therapeutic options.

Prevalence and incidence of osteoporotic fractures in patients on long-term glucocorticoid treatment for rheumatic diseases: the Glucocorticoid Induced OsTeoporosis TOol (GIOTTO) study.

Osteoporosis and fractures are common and invalidating consequences of chronic glucorticoid (GC) treatment. Reliable information regarding the epidemiology of GC induced osteoporosis (GIOP) comes exclusively from the placebo group of randomized clinical trials while observational studies are generally lacking data on the real prevalence of vertebral fractures, GC dosage and primary diagnosis. The objective of this study was to evaluate the prevalence and incidence of osteoporotic fractures and to identify their major determinants (primary disease, GC dosage, bone mineral density, risk factors, specific treatment for GIOP) in a large cohort of consecutive patients aged >21 years, on chronic treatment with GC (≥5 mg prednisone - PN - equivalent) and attending rheumatology centers located all over Italy. Glucocorticoid Induced OsTeoporosis TOol (GIOTTO) is a national multicenter cross-sectional and longitudinal observational study. 553 patients suffering from Rheumatoid Arthritis (RA), Polymyalgia Rheumatica (PMR) and Connective Tissue Diseases (CTDs) and in chronic treatment with GCs were enrolled. Osteoporotic BMD values (T score <-2.5) were observed in 28%, 38% and 35% of patients with CTDs, PMR or RA at the lumbar spine, and in 18%, 29% and 26% at the femoral neck, respectively. Before GC treatment, prevalent clinical fractures were reported by 12%, 37% and 17% of patients with CTDs, PMR, or RA, respectively. New clinical fragility fractures during GC treatment were reported by 12%, 10% and 23% of CTDs, PMR and RA patients, respectively. Vertebral fractures were the prevailing type of fragility fracture. More than 30% of patients had recurrence of fracture. An average of 80% of patients were in supplementation with calcium and/or vitamin D during treatment with GCs. Respectively, 64%, 80%, and 72% of the CTDs, PMR and RA patients were on pharmacological treatment for GIOP, almost exclusively with bisphosphonates. The GIOTTO study might provide relevant contributions to clinical practice, in particular by highlighting and quantifying in real life the prevalence of GIOP and relative fractures, the frequency of the main risk factors, and the currently sub-optimal prevention. Moreover, these results emphasize the importance of the underlying rheumatic disease on the risk of GIOP associated fractures.

Population-based analysis of hospitalizations in a West-European region revealed major changes in hospital utilization for patients with systemic lupus erythematosus over the period 2001-2012.

OBJECTIVE: The objective of this paper is to evaluate hospital admissions in systemic lupus erythematosus (SLE) patients through a retrospective population-based study analyzing hospitalization data during 2001-2012 in Sardinia, an Italian region with universal health system coverage. METHODS: Data on the hospital discharge records with the ICD-9-CM code for SLE (710.0) were obtained from the Department of Health and Hygiene and analyzed, mostly focusing on primary and non-primary diagnosis and Diagnosis-Related Group (DRG) code. In order to establish the significance of the annual trend for number and type of primary and non-primary discharge diagnosis, the two-tailed Cochran-Armitage test for trend was applied. In order to estimate SLE prevalence, data from administrative database and medical records were assembled. RESULTS: This study included 6222 hospitalizations in 1675 patients (87% women). Hospitalizations with SLE as primary diagnosis were 3782 (58.0%) and significantly decreased during the study period. The annual number of renal, hematologic and neuropsychiatric disorders as non-primary diagnosis associated with SLE remained constant; however, their percentage increased (p < 0.0001) because of a declining number of admissions for SLE without associated diagnosis and without complications. Hospitalizations with SLE as non-primary diagnosis showed a significant upward trend in number and percentage of cerebrovascular accident (p = 0.0004), acute coronary syndrome (p = 0.0004) and chronic renal failure (p = 0.0003) as underlying primary diagnosis, while complications of pregnancy, labor and childbirth (p = 0.3375), malignancies (p = 0.6608) and adverse drug reactions (p = 0.2456) did not show statistically significant changes. Infections showed an increasing trend between 2001 and 2012 but did not reach statistical significance (p = 0.0304). After correction for hospitalization (93.8%) and survival (91.1%) rates calculated over the study period, the 2012 SLE prevalence in Sardinia was estimated to be 99.3 per 100,000 inhabitants. CONCLUSIONS: While overall hospitalizations for SLE patients declined, those for cerebrovascular accident, acute coronary syndrome and chronic renal failure as underlying primary diagnosis increased during the study period.

Direct involvement of DprA, the transformation-dedicated RecA loader, in the shut-off of pneumococcal competence.

Natural bacterial transformation is a genetically programmed process allowing genotype alterations that involves the internalization of DNA and its chromosomal integration catalyzed by the universal recombinase RecA, assisted by its transformation-dedicated loader, DNA processing protein A (DprA). In Streptococcus pneumoniae, the ability to internalize DNA, known as competence, is transient, developing suddenly and stopping as quickly. Competence is induced by the comC-encoded peptide, competence stimulating peptide (CSP), via a classic two-component regulatory system ComDE. Upon CSP binding, ComD phosphorylates the ComE response-regulator, which then activates transcription of comCDE and the competence-specific σ(X), leading to a sudden rise in CSP levels and rendering all cells in a culture competent. However, how competence stops has remained unknown. We report that DprA, under σ(X) control, interacts with ComE∼P to block ComE-driven transcription, chiefly impacting σ(X) production. Mutations of dprA specifically disrupting interaction with ComE were isolated and shown to map mainly to the N-terminal domain of DprA. Wild-type DprA but not ComE interaction mutants affected in vitro binding of ComE to its promoter targets. Once introduced at the dprA chromosomal locus, mutations disrupting DprA interaction with ComE altered competence shut-off. The absence of DprA was found to negatively impact growth following competence induction, highlighting the importance of DprA for pneumococcal physiology. DprA has thus two key roles: ensuring production of transformants via interaction with RecA and competence shut-off via interaction with ComE, avoiding physiologically detrimental consequences of prolonged competence. Finally, phylogenetic analyses revealed that the acquisition of a new function by DprA impacted its evolution in streptococci relying on ComE to regulate comX expression.

Early Lupus Project - A multicentre Italian study on systemic lupus erythematosus of recent onset.

BACKGROUND: Systemic lupus erythematosus (SLE) is an autoimmune disease with a high degree of variability at onset that is problematic for a correct and prompt diagnosis. We undertook this project with the purpose of collecting an inception cohort of Italian patients with recent-onset SLE, in order to obtain information on the main clinical and serological characteristics at the beginning of the disease. In this first report we describe the characteristics of this cohort at study entry. METHODS: All patients with a diagnosis of SLE (1997 ACR criteria) and a disease duration less than 12 months were consecutively enrolled between 1 January 2012 and 31 December 2013 in a multicentre prospective study. Information on clinical and serological characteristics at study entry and then every six months was collected into a specific electronic database. Statistical analysis was performed by means of the Openstat program. RESULTS: Among 122 patients enrolled (103 F) 94.3% were Caucasians. Mean age (SD) of patients at study entry was 37.3 (14.3) years, mean age at disease onset was 34.8 (14.3) years, mean age at diagnosis was 36.9 (14.3) years, and mean disease duration was 2.9 (3.9) months. The frequency of the manifestations included in the 1997 ACR criteria was as follows: ANA 97.5%, immunologic disorders (anti-dsDNA, anti-Sm, antiphospholipid antibodies) 85.2%, arthritis 61.8%, haematologic disorders 55.7%, malar rash 31.1%, photosensitivity 29.5%, serositis 27%, renal disorders 27%, oral/nasal ulcers 11.5%, neurologic disorders 8.2%, and discoid rash 5.7%. The cumulative frequency of mucocutaneous symptoms was 77.8%. At enrolment, autoantibody frequency was: ANA 100%, anti-dsDNA 83.6%, anti-SSA 28%, anticardiolipin 24.5%, anti-nRNP 20.4%, anti-beta2GPI 17.2%, lupus anticoagulant 16.3%, anti-Sm 16%, and anti-SSB 13.1%. CONCLUSIONS: In this paper we describe the main clinical and serological characteristics of an Italian inception cohort of patients with recent-onset SLE. At disease onset, mucocutaneous manifestations, arthritis and haematologic manifestations were the most frequent symptoms; ANA, anti-dsDNA and complement reduction were the most frequent laboratory findings. Our data confirm that the diagnosis of SLE is a challenging one, and that SLE is a severe disease even at onset, since the majority of patients require at least a hospitalization before the diagnosis.

Resistance to Downy Mildew in Lettuce 'La Brillante' is Conferred by Dm50 Gene and Multiple QTL.

Many cultivars of lettuce (Lactuca sativa L.) are susceptible to downy mildew, a nearly globally ubiquitous disease caused by Bremia lactucae. We previously determined that Batavia type cultivar 'La Brillante' has a high level of field resistance to the disease in California. Testing of a mapping population developed from a cross between 'Salinas 88' and La Brillante in multiple field and laboratory experiments revealed that at least five loci conferred resistance in La Brillante. The presence of a new dominant resistance gene (designated Dm50) that confers complete resistance to specific isolates was detected in laboratory tests of seedlings inoculated with multiple diverse isolates. Dm50 is located in the major resistance cluster on linkage group 2 that contains at least eight major, dominant Dm genes conferring resistance to downy mildew. However, this Dm gene is ineffective against the isolates of B. lactucae prevalent in the field in California and the Netherlands. A quantitative trait locus (QTL) located at the Dm50 chromosomal region (qDM2.2) was detected, though, when the amount of disease was evaluated a month before plants reached harvest maturity. Four additional QTL for resistance to B. lactucae were identified on linkage groups 4 (qDM4.1 and qDM4.2), 7 (qDM7.1), and 9 (qDM9.2). The largest effect was associated with qDM7.1 (up to 32.9% of the total phenotypic variance) that determined resistance in multiple field experiments. Markers identified in the present study will facilitate introduction of these resistance loci into commercial cultivars of lettuce.