Nod1, an Apaf-1-like activator of caspase-9 and nuclear factor-kappaB

Ced-4 and Apaf-1 belong to a major class of apoptosis regulators that contain caspase-recruitment (CARD) and nucleotide-binding oligomerization domains. Nod1, a protein with an NH2-terminal CARD-linked to a nucleotide-binding domain and a COOH-terminal segment with multiple leucine-rich repeats, was identified. Nod-1 was found to bind to multiple caspases with long prodomains, but specifically activated caspase-9 and promoted caspase-9-induced apoptosis. As reported for Apaf-1, Nod1 required both the CARD and P-loop for function. Unlike Apaf-1, Nod1 induced activation of nuclear factor-kappa-B (NF-kappaB) and bound RICK, a CARD-containing kinase that also induces NF-kappaB activation. Nod1 mutants inhibited NF-kappaB activity induced by RICK, but not that resulting from tumor necrosis factor-alpha stimulation. Thus, Nod1 is a leucine-rich repeat-containing Apaf-1-like molecule that can regulate both apoptosis and NF-kappaB activation pathways.

Compromises between water-use efficiency and nitrogen-use efficiency in five species of California evergreens

In five California evergreen trees and shrubs cooccurring in this study but most common in habitats of different moisture availability, leaf nitrogen was a major determinant of photosynthetic capacity. Within each species, stomatal conductance was highly correlated with photosynthetic capacity, resulting in little variation in the concentration of CO₂ in the intercellular spaces. Among species, intercellular CO₂ concentrations varied significantly. Under controlled conditions, the leaves that realized the highest photosynthesis per unit of leaf nitrogen tended to realize the lowest photosynthesis per unit of water transpired. The ratio of photosynthesis to transpiration, an instantaneous measure of intrinsic water-use efficiency, was highest in the species commonly found in the direst habitats and lowest in the species most common in the wettes habitats.

Epicardial ablation for ventricular tachycardia: a European multicenter study

BACKGROUND

The purpose of this study was to describe the epicardial percutaneous ablation experience of 6 European high-volume ventricular tachycardia (VT) ablation centers.

METHODS AND RESULTS

Data from 218 patients with coronary artery disease (CAD, n=85 [39.0%]), idiopathic dilated of patients with idiopathic VT cardiomyopathy (IDCM, n=67 [30.7%]), arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARCD/C, n=13 [6%]), hypertrophic cardiomyopathy (HCM, n=5 [2.3%]), and absence of structural heart disease (n=48 [22%]) undergoing epicardial subxyphoid access for VT ablation were collected. The epicardial approach was attempted as first-line treatment in 78 patients (35.8%). Acute prevention of VT inducibility was obtained in 156 patients (71.6%). There were no procedure-related deaths. Cardiac tamponade occurred in 8 patients, and abdominal hemorrhage in 1 patient. Six patients died of electrical storm recurrence within 48 hours from the procedure. After a mean follow-up of 17.3±18.2 months, 60 patients (31.4%) presented with VT recurrence (39.3% of IDCM patients; 34.7% of CAD patients; 30.8% of ARVD/C patients; 25% of HCM patients; 17.1% of patients with idiopathic VT). Twenty patients (10.4%) died during follow-up (12 of heart failure, 2 of cardiac arrest, and 6 of extracardiac causes).

CONCLUSIONS

In experienced centers, epicardial ablation of VT has an acceptable risk and favorable outcome. In selected patients, it is reasonable to consider as a first-line ablation approach.

The increase of IFN-gamma production through aging correlates with the expanded CD8(+high)CD28(-)CD57(+) subpopulation

The use of flow cytometry to detect intracellular cytokines at the single cell level has the potential to quantify cytokine production together with the possibility of phenotypic identification of the cell population concerned. The unbalanced presence of intracellular cytokines produced by T cells has been recognized in some pathological conditions. To better address this issue, we studied the production of IFN-gamma and IL-4 in CD4(+) and CD8(+high) T cells in healthy donors of a broad range of age (17-62 years). Given that an increase of IFN-gamma and IL-4 with aging had been reported by some authors in healthy controls, we have performed a multivariate analysis to assess the intrinsic role of aging or of other external factors, such as chronic antigenic exposures (i.e., viruses), over the cytokine production of phenotypically characterized T cells. In this respect we show that, mainly in CD8(+high) T cells, the production of IFN-gamma is directly correlated with age. Besides, the cytokine production correlates with the CD8(+high)CD28(-)CD57(+) T-cell population, which we have recently reported elevated in aged individuals. Perhaps this T-cell subpopulation plays a regulatory role as a Tc1 response in aging individuals.

Diva, a Bcl-2 homologue that binds directly to Apaf-1 and induces BH3-independent cell death

We have identified and characterized Diva, which is a novel regulator of apoptosis. Sequence analysis revealed that Diva is a member of the Bcl-2 family of proteins containing Bcl-2 homology domain 1, 2, 3, and 4 (BH1, BH2, BH3, and BH4) regions and a carboxyl-terminal hydrophobic domain. The expression of Diva mRNA was detected in multiple embryonic tissues but was restricted to the ovary and testis in adult mice. The expression of Diva promoted the death of 293T, Ramsey, and T47D cells as well as that of primary sensory neurons, indicating that Diva is a proapoptotic protein. Significantly, Diva lacks critical residues in the conserved BH3 region that mediate the interaction between BH3-containing proapoptotic Bcl-2 homologues and their prosurvival binding partners. Consistent with this, Diva did not bind to cellular Bcl-2 family members including Bcl-2, Bcl-XL, Bcl-w, Mcl-1, and A1/Bfl-1. Furthermore, mutants of Diva lacking the BH3 region fully retained their proapoptotic activity, confirming that Diva promotes apoptosis in a BH3-independent manner. Significantly, Diva interacted with a viral Bcl-2 homologue (vBcl-2) encoded by the Kaposi's sarcoma-associated herpesvirus. Consistent with these associations, apoptosis induced by Diva was inhibited by vBcl-2 but not by Bcl-XL. Importantly, Diva interacted with Apaf-1, an adapter molecule that activates caspase-9, a central death protease of the apoptotic pathway. The expression of Diva inhibited the binding of Bcl-XL to Apaf-1, as determined by immunoprecipitation assays. Thus, Diva represents a novel type of proapoptotic Bcl-2 homologue that promotes apoptosis independently of the BH3 region through direct binding to Apaf-1, thus preventing Bcl-XL from binding to the caspase-9 regulator Apaf-1.

CIPER, a novel NF kappaB-activating protein containing a caspase recruitment domain with homology to Herpesvirus-2 protein E10

We have identified and characterized CIPER, a novel protein containing a caspase recruitment domain (CARD) in its N terminus and a C-terminal region rich in serine and threonine residues. The CARD of CIPER showed striking similarity to E10, a product of the equine herpesvirus-2. CIPER formed homodimers via its CARD and interacted with viral E10 but not with several apoptosis regulators containing CARDs including ARC, RAIDD, RICK, caspase-2, caspase-9, or Apaf-1. Expression of CIPER induced NF-kappaB activation, which was inhibited by dominant-negative NIK and a nonphosphorylable IkappaB-alpha mutant but not by dominant-negative RIP. Mutational analysis revealed that the N-terminal region of CIPER containing the CARD was sufficient and necessary for NF-kappaB-inducing activity. Point mutations in highly conserved residues in the CARD of CIPER disrupted the ability of CIPER to activate NF-kappaB and to form homodimers, indicating that the CARD is essential for NF-kappaB activation and dimerization. We propose that CIPER acts in a NIK-dependent pathway of NF-kappaB activation.

Mtd, a novel Bcl-2 family member activates apoptosis in the absence of heterodimerization with Bcl-2 and Bcl-XL

We have identified and characterized Mtd, a novel regulator of apoptosis. Sequence analysis revealed that Mtd is a member of the Bcl-2 family of proteins containing conserved BH1, BH2, BH3, and BH4 regions and a carboxyl-terminal hydrophobic domain. In adult tissues, Mtd mRNA was predominantly detected in the brain, liver, and lymphoid tissues, while in the embryo Mtd mRNA was detected in the liver, thymus, lung, and intestinal epithelium. Expression of Mtd promoted the death of primary sensory neurons, 293T cells and HeLa cells, indicating that Mtd is a proapoptotic protein. Unlike all other known death agonists of the Bcl-2 family, Mtd did not bind significantly to the survival-promoting proteins Bcl-2 or Bcl-XL. Furthermore, apoptosis induced by Mtd was not inhibited by Bcl-2 or Bcl-XL. A Mtd mutant with glutamine substitutions of highly conserved amino acids in the BH3 domain retained its ability to promote apoptosis, further indicating that Mtd does not promote apoptosis by heterodimerizing with Bcl-2 or Bcl-XL. Mtd-induced apoptosis was not blocked by broad range synthetic caspase inhibitors z-VAD-fmk or a viral protein CrmA. Mtd is the first example of a naturally occurring Bcl-2 family member that can activate apoptosis independently of heterodimerization with survival-promoting Bcl-2 and Bcl-XL.

Progressive decrease of CD8high+ CD28+ CD57- cells with ageing

An age-dependent decrease in T cell responsiveness to CD28 costimulation has been described. In order to test the hypothesis that an age-related decrease in CD28 expression by CD8+ T lymphocytes might be involved, we analysed 67 healthy donors ranging in age from 15 to 69 years for their CD8+ T cell expression of CD28 and CD57. We found a statistically significant decrease of CD28 expression through ageing and a significant increase of CD57 expression, both markers being mutually exclusive. Given that cytomegalovirus (CMV) is reported to induce CD57 expression, and since the carrier status for this ubiquitous virus increases with age in the general population, it seemed essential to evaluate whether the phenotypic age-related changes described in CD8high+ cells were not influenced by the CMV carrier status of the individuals. Accordingly, we performed a multivariate analysis to assess the independent association of age and CMV carrier status with CD28 and CD57 expression in CD8high+ cells. Results showed that the progressive decrease in CD8high+ CD28+ CD57- cells was associated only with age, while the expansion of the CD8high+ CD28- CD57+ subset depended both on age and CMV, although mainly on age. We conclude that ageing is accompanied by a progressive loss of CD28 expression in CD8+ T cells and a reciprocal enhancement of CD57 expression, both facts being probably related to the repeated antigenic stimulation occurring throughout life.

Next generation flow for minimally-invasive blood characterization of MGUS and multiple myeloma at diagnosis based on circulating tumor plasma cells (CTPC)

Here, we investigated for the first time the frequency and number of circulating tumor plasma cells (CTPC) in peripheral blood (PB) of newly diagnosed patients with localized and systemic plasma cell neoplasms (PCN) using next-generation flow cytometry (NGF) and correlated our findings with the distinct diagnostic and prognostic categories of the disease. Overall, 508 samples from 264 newly diagnosed PCN patients, were studied. CTPC were detected in PB of all active multiple myeloma (MM; 100%), and smoldering MM (SMM) patients (100%), and in more than half (59%) monoclonal gammopathy of undetermined significance (MGUS) cases (p <0.0001); in contrast, CTPC were present in a small fraction of solitary plasmacytoma patients (18%). Higher numbers of CTPC in PB were associated with higher levels of BM infiltration and more adverse prognostic features, together with shorter time to progression from MGUS to MM (p <0.0001) and a shorter survival in MM patients with active disease requiring treatment (p ≤ 0.03). In summary, the presence of CTPC in PB as assessed by NGF at diagnosis, emerges as a hallmark of disseminated PCN, higher numbers of PB CTPC being strongly associated with a malignant disease behavior and a poorer outcome of both MGUS and MM.

Dark Leaf Respiration in Light and Darkness of an Evergreen and a Deciduous Plant Species

Dark respiration in light as well as in dark was estimated for attached leaves of an evergreen (Heteromeles arbutifolia Ait.) and a deciduous (Lepechinia fragans Greene) shrub species using an open gas-exchange system. Dark respiration in light was estimated by the Laisk method. Respiration rates in the dark were always higher than in the light, indicating that light inhibited respiration in both species. The rates of respiration in the dark were higher in the leaves of the deciduous species than in the evergreen species. However, there were no significant differences in respiration rates in light between the species. Thus, the degree of inhibition of respiration by light was greater in the deciduous species (62%) than in the evergreen species (51%). Respiration in both the light and darkness decreased with increasing leaf age. However, because respiration in the light decreased faster with leaf age than respiration in darkness, the degree of inhibition of respiration by light increased with leaf age (from 36% in the youngest leaves to 81% in the mature leaves). This suggests that the rate of dark respiration in the light is related to the rate of biosynthetic processes. Dark respiration in the light decreased with increasing light intensity. Respiration both in the light and in the dark was dependent on leaf temperature. We concluded that respiration in light and respiration in darkness are tightly coupled, with variation in respiration in darkness accounting for more than 60% of the variation in respiration in light. Care must be taken when the relation between respiration in light and respiration in darkness is studied, because the relation varies with species, leaf age, and light intensity.

Fusion of the human gene for the polyubiquitination coeffector UEV1 with Kua, a newly identified gene

UEV proteins are enzymatically inactive variants of the E2 ubiquitin-conjugating enzymes that regulate noncanonical elongation of ubiquitin chains. In Saccharomyces cerevisiae, UEV is part of the RAD6-mediated error-free DNA repair pathway. In mammalian cells, UEV proteins can modulate c-FOS transcription and the G2-M transition of the cell cycle. Here we show that the UEV genes from phylogenetically distant organisms present a remarkable conservation in their exon-intron structure. We also show that the human UEV1 gene is fused with the previously unknown gene Kua. In Caenorhabditis elegans and Drosophila melanogaster, Kua and UEV are in separated loci, and are expressed as independent transcripts and proteins. In humans, Kua and UEV1 are adjacent genes, expressed either as separate transcripts encoding independent Kua and UEV1 proteins, or as a hybrid Kua-UEV transcript, encoding a two-domain protein. Kua proteins represent a novel class of conserved proteins with juxtamembrane histidine-rich motifs. Experiments with epitope-tagged proteins show that UEV1A is a nuclear protein, whereas both Kua and Kua-UEV localize to cytoplasmic structures, indicating that the Kua domain determines the cytoplasmic localization of Kua-UEV. Therefore, the addition of a Kua domain to UEV in the fused Kua-UEV protein confers new biological properties to this regulator of variant polyubiquitination.

Control of diabetes and cardiovascular risk factors in patients with type 2 diabetes in primary care. The gap between guidelines and reality in Spain

To evaluate the level and factors affecting control of diabetes and cardiovascular risk factors in type 2 diabetes (TYPE 2 DM) patients. Multicentre cross-sectional study: a sample of 430 primary care practices across Spain selected 1907 type 2 diabetic patients. The first five consecutive ambulatory patients with TYPE 2 DM were eligible for the inclusion into the survey. Patients were free of known cardiovascular disease (CVD). Control criteria were defined based on 2002 American Diabetes Association (ADA) clinical practice recommendations. A total of 1907 patients (51% women) aged 63 +/- 9 years. Smoking prevalence was 22.6%, 50.6% had levels of A1c < 7%. Mean blood pressure (BP) was 148 +/- 17/86 +/- 10 mmHg. Only 7.8% have achieved the target of BP < 130/80 mmHg. Among the 1180 patients (65%) treated for hypertension, this target was attained in only 4.4% of patients. A measurement for low-density lipoprotein (LDL) cholesterol was available in 1669 patients (88%). Only 5.9% of patients achieved the target of LDL < 100 mg/dl. Among the 638 patients (41.6%) on drug treatment for dyslipidaemia, this target was attained in only 5.6% of patients. Among type 2 diabetic patients in Spain the prevalence of cardiovascular risk factors is high. Control of glycaemia, smoking, BP and LDL are far from optimal despite the widespread use of guidelines for the management of diabetes and CVD. The application of published recommendations needs to be reinforced.

Comparison of Methods to Estimate Dark Respiration in the Light in Leaves of Two Woody Species

Dark respiration in the light was estimated in leaves of two woody species (Heteromeles arbutifolia Ait. and Lepechinia fragans Greene) using two different approaches based on gas-exchange techniques: the Kok method and the Laisk method. In all cases, dark respiration in the light was lower (P < 0.05) than respiration in darkness, indicating that dark respiration was inhibited in the light. Rates of dark respiration in the light estimated by the Laisk method were 52% higher (P < 0.05) than those estimated by the Kok method. Differences between the methods could be explained by the low ambient CO2 concentrations required by the Laisk approach. The mean value of the inhibition of respiration by light for the two species, corrected for the ambient CO2 concentration effect, was 55%. Despite the differences in leaf characteristics between the species, values of the CO2 photocompensation point, at which the rate of photosynthetic CO2 uptake equaled that of photorespiratory CO2 evolution, were very constant, suggesting an excellent consistency in the results obtained with the Laisk approach.

Clinical study of an outbreak of Legionnaire's disease in Alcoy, Southeastern Spain

The aim of this study was to identify the clinical features of Legionnaires' disease, sudden outbreaks of which demand a quick and flexible clinical approach, particularly with regard to diagnosis and therapy. A prospective and comparative study based on a clinical protocol was performed during an outbreak of Legionnaires' disease in Alcoy, Spain. The outbreak was environmental in origin, linked to cooling towers. Data about epidemiological and clinical features, blood chemistry values, radiological and microbiological findings, and characteristics related to the clinical course of Legionnaires' disease were obtained for 357 patients admitted to hospital with community-acquired pneumonia (177 with Legionella pneumonia). Patients with Legionnaires' disease were younger (mean age, 65.3+/-16.5 years) and more likely to be smokers compared with patients with other types of pneumonia (28.8% vs. 11.1%; P<0.01). Moreover, they had not been admitted to any hospital because of pneumonia in the previous year. Patients with Legionnaires' disease had higher fever, more severe headache, and less expectoration as well as lower sodium blood levels (mean, 132.6+/-4.8 mmol/l vs. 135.7 mmol/l; P<0.01). Radiological studies also showed that fewer patients with Legionnaires' disease had pleural effusion (9% vs. 19.4% of those with non- Legionella pneumonia). The presence of headache, high fever, hyponatremia, scanty or null expectoration, and current cigarette smoking provides physicians with important clues for a high suspicion of Legionella pneumonia before the results of confirmatory laboratory tests are available.

Quantification and characterization of carotid calcium with multi-detector CT-angiography

OBJECTIVE

The aim of this study was to assess the accuracy of CT-angiography for identification and measurement of calcification of carotid atherosclerotic plaques and to characterise the content and distribution pattern of mineral calcium (hydroxyapatite, Ca) in carotid bifurcations and investigate its relationship with neurological symptoms.

METHODS

Twenty-six patients with ICA stenosis > 60% (13 symptomatic, 13 asymptomatic) were selected for study. Ca was estimated from the weight of the ashed remnants of carotid endarterectomy (CEA) specimens in 11 patients. Calcium content (calcification volume (mm3),CV), and average calcium density (Hounsfield units (HU),CD), were determined by CT-angiography. The distribution pattern of calcium within the lesion (base (posterior), shoulder or luminal surface) was assessed in all cases.

RESULTS

CT-derived estimation of CV and Ca mass (modified Agatston Score, (mAS) = CV x CD) showed a good correlation with its direct measurement in CEA specimens (r = 0.911 and 0.993 respectively, p < 0,005). Asymptomatic patients with ICA stenosis > 60% showed statistically significant higher content of Ca than those who were symptomatic (mAS: 122.6 +/- 138.0 HU mm3 vs 42.8 +/- 59.1 HU mm3, p = 0.04). Calcification on the surface of the plaque was observed more commonly in asymptomatic patients (9/12 vs 3/15, p = 0.006). Non-calcified or plaques with posterior calcification were 12 times more likely to be symptomatic (OR: 12, 95%CI 1.5-91.1, p = 0.021).

CONCLUSIONS

CT-angiography permits the reliable quantification of calcification of carotid plaques. A lower content of calcium in carotid plaques, as well as its distribution in the base of the lesion, was associated with a greater prevalence of neurological symptoms. These parameters may be useful to identify those patients at higher risk of stroke.

A prospective study of stroke in young adults in Cantabria, Spain

BACKGROUND AND PURPOSE

The aim of this study was to determine the incidence, type, and prognosis of stroke in young adults in Cantabria, Spain.

METHODS

We investigated prospectively all patients aged 50 years or below who were admitted with the diagnosis of a stroke to the University Hospital "Marqués de Valdecilla" from April 1, 1986, to March 31, 1988. This is the main hospital of the region to which all patients with neurological problems are referred. These patients underwent a complete clinical and laboratory assessment for stroke and had 1-year mean follow-up.

RESULTS

The total series included 81 patients. The annual age-specific crude incidence rates of stroke were 17.3 and 10.4 per 100,000 for males and females, respectively. Twenty-four patients (30%) were diagnosed as having nonembolic cerebral infarction, 14 (17%) embolic cerebral infarction, 20 (25%) subarachnoid hemorrhage, 22 (27%) spontaneous cerebral hemorrhage, and one case (1%) cerebral venous thrombosis. Eighteen patients (22%) died within 30 days of the cerebrovascular event, and two others died during the follow-up period. Seventy-nine percent of the survivors recovered and were completely self-sufficient.

CONCLUSIONS

The incidence of stroke in the young found in Cantabria is comparable with that in previous studies. The initial hospital mortality was not negligible, but the prognosis among the survivors was favorable.

Multifactorial approach and adherence to prescribed oral medications in patients with type 2 diabetes

The aims of this study were to assess adherence to oral hypoglycaemic/cardiovascular drugs and determine non-adherence predictors in type 2 diabetes patients. It was designed as a population-based cross-sectional study in which 90 patients from a primary care setting were studied. Pill count and self-report methods were used to measure adherence. Logistic regression analysis was performed to predict factors related to non-adherence. Adequate adherence to all drugs was found in 29 patients (35.4%; 95% confidence interval (CI) 25.0-45.7). Variables associated with non-adherence were HbA1c odds ratio (OR) 2.32 (95% CI: 1.09-4.95), systolic blood pressure OR 1.68 (95% CI: 1.08-2.62), total cholesterol OR 1.34 (95% CI: 1.08-1.66), number of pills OR 1.80 (95% CI: 1.26-2.55) and duration of disease OR 0.44 (CI 95%: 0.24-0.83). In conclusion, one in three patients had adequate adherence. Factors associated with non-adherence were duration of disease, complexity of drug regimen and inadequate control of cardiovascular risk factors.

Effect of long-term anti-CD4 or anti-CD8 treatment on the development of lpr CD4- CD8- double negative T cells and of the autoimmune syndrome in MRL-lpr/lpr mice

We have determined the effect of anti-CD4 or anti-CD8 monoclonal antibody (mAb) treatment from birth on the generation of the lpr CD4- CD8- double-negative (DN) T cell subset and on the development of lupus-like autoimmune syndrome in MRL-lpr/lpr mice. Both anti-CD4 and anti-CD8 mAb treatments resulted in a marked inhibition of lymph-adenopathy, whereas the development of the lpr DN T cells and of the lupus-like autoimmune syndrome strikingly differed in these two groups of mice. The treatment with anti-CD8 mAb almost completely blocked the appearance of the lpr DN T cells without any significant effect on the development of lupus-like autoimmune syndrome in MRL-lpr/lpr mice. In contrast, mice treated with anti-CD4 mAb failed to develop a lupus-like syndrome, while they still developed the lpr DN T cell subset, the predominant population in their lymph nodes, although absolute numbers were markedly diminished. Our results support the idea that CD8+ T cells are a major source of the lpr DN T cells, and that the lpr DN T cells play a minor, if any, role in the pathogenesis of lupus-like autoimmune syndrome in MRL-lpr/lpr mice.

Screening for sight threatening diabetic retinopathy using non-mydriatic retinal camera in a primary care setting: to dilate or not to dilate?

OBJECTIVES

To evaluate three different strategies (without or with mydriasis) for community based screening for sight threatening diabetic retinopathy (STDR).

DESIGN

A masked cross-sectional comparative study.

SETTING

Primary care centre.

PARTICIPANTS

216 type-1 and type-2 diabetic patients (432 eyes).

INTERVENTIONS

Screening for STDR was performed with the Topcon CRW6S non-mydriatic camera (NMC), compared with the grading of the seven-field standard stereoscopic photographs, 30 degrees field photographs with mydriasis as the gold standard method. Three fields were studied: Field 1 centred on the macula; field 2 centred on the disc and the macula and field 3 centred on the disc, on the macula and temporal upper to the macula all without and with mydriasis.

MAIN OUTCOME MEASURES

Sensitivity and specificity of screening method and prevalence of STDR. Strategies: field 1 (macular), addition of field 2 (nasal), addition of field 3 (superior temporal) all without and with mydriasis.

RESULTS

The prevalence of STDR was 14.3%. When screening without mydriasis is performed, the percentage of referred patients increases from 14% (STDR) to almost 33% because of ungradable photographs. Sensitivity of detection of STDR by NMC using single field with mydriasis was 82% (95% confidence interval 72-92%) and without mydriasis 67% (54-80%). Specificity was 99% (97-100%) for single field with mydriasis and 99% (98-100%) without mydriasis. Sensitivity of detection using two fields with mydriasis was 95% (89-100%); without mydriasis (54-80%), slightly better than single field with mydriasis (72-92%). Specificity was similar.

CONCLUSIONS

Screening for STDR with NMC can be performed effectively with one non-stereoscopic retinal photograph per eye with mydriasis using tropicamide 0.5%. Screening without mydriasis increases the number of patients to be referred.

Managing reversal of direct oral anticoagulants in emergency situations

Anticoagulation is the cornerstone of prevention and treatment of venous thromboembolism (VTE) and stroke prevention in patients with atrial fibrillation (AF). However, the mechanisms by which anticoagulants confer therapeutic benefit also increase the risk of bleeding. As such, reversal strategies are critical. Until recently, the direct oral anticoagulants (DOACs) dabigatran, rivaroxaban, apixaban, and edoxaban lacked a specific reversal agent. This report is based on findings from the Anticoagulation Education Task Force, which brought together patient groups and professionals representing different medical specialties with an interest in patient safety and expertise in AF, VTE, stroke, anticoagulation, and reversal agents, to discuss the current status of anticoagulation reversal and fundamental changes in management of bleeding associated with DOACs occasioned by the approval of idarucizumab, a specific reversal agent for dabigatran, as well as recent clinical data on specific reversal agents for factor Xa inhibitors. Recommendations are given for when there is a definite need for a reversal agent (e.g. in cases of life-threatening bleeding, bleeding into a closed space or organ, persistent bleeding despite local haemostatic measures, and need for urgent interventions and/or interventions that carry a high risk for bleeding), when reversal agents may be helpful, and when a reversal agent is generally not needed. Key stakeholders who require 24–7/around-the-clock access to these agents vary among hospitals; however, from a practical perspective the emergency department is recommended as an appropriate location for these agents. Clearly, the advent of new agents requires standardised protocols for treating bleeding on an institutional level.

Increased IgA-producing cells in the blood of patients with active Henoch-Schönlein purpura

Peripheral blood lymphocytes (PBL) producing IgA, IgM, and IgG, both spontaneously and after pokeweed mitogen stimulation in cell culture, were determined by a protein A hemolytic plaque assay in 20 children with active Henoch-Schönlein purpura (HSP), 42 with inactive disease, 22 normal controls of the same ages, and 18 children with upper respiratory tract infections (URTI). The geometric mean of circulating IgA-producing cells in active HSP (1,016 X divided by 1.55 cells/10(6) PBL) was increased when compared with the group with inactive disease (P less than 0.001), normal controls (P less than 0.001), and children with URTI (542 X divided by 2.03 cells/10(6) PBL, P less than 0.05). The number of circulating IgM-producing cells was slightly increased in active HSP (260 X divided by 2.65 cells/10(6) PBL) and URTI (256 X divided by 3.16 cells/10(6) PBL). Both values were higher than those found in the group with inactive disease (113 X divided by 2.26 cells/10(6) PBL, P less than 0.01). There were no significant differences among the 4 groups in the number of circulating IgG-producing cells. The number of cells producing each type of immunoglobulin after in vitro stimulation with pokeweed mitogen was similar in patients with active HSP, normal controls, and the group with inactive disease. These data demonstrate a selective increase in the number of circulating IgA-producing cells only during disease activity, and add further support to a possible pathogenic role of this immunoglobulin in HSP.

Constitutive expression of bcl-2 in B cells causes a lethal form of lupuslike autoimmune disease after induction of neonatal tolerance to H-2b alloantigens

The bcl-2 protooncogene has been shown to provide a survival signal to self-reactive B cells, but it fails to override their developmental arrest after encounter with antigen. Furthermore, constitutive expression of bcl-2 in B cells does not promote the development of autoimmune disease in most strains of mice, indicating that signals other than those conferred by bcl-2 are required for long-term survival and differentiation of self-reactive B cells in vivo. To further examine the factors that are required for the pathogenesis of autoimmune disease, we have assessed the effect of bcl-2 overexpression on the development of host-versus-graft disease, a self-limited model of systemic autoimmune disease. In this model, injection of spleen cells from (C57BL/6 x BALB/c)F1 hybrid mice into BALB/c newborn parental mice induces immunological tolerance to donor tissues and activation of autoreactive F1 donor B cells through interactions provided by allogeneic host CD4+ T cells. BALB/c newborns injected with spleen cells from (C57BL/6 x BALB/c)F1 mice expressing a bcl-2 transgene in B cells developed high levels of anti-single-stranded DNA and a wide range of pathogenic autoantibodies that were not or barely detectable in mice injected with nontransgenic spleen cells. In mice injected with transgenic B cells, the levels of pathogenic autoantibodies remained high during the course of the study and were associated with long-term persistence of donor B cells, development of a severe autoimmune disease, and accelerated mortality. These results demonstrate that bcl-2 can provide survival signals for the maintenance and differentiation of autoreactive B cells, and suggest that both increased B cell survival and T cell help play critical roles in the development of certain forms of systemic autoimmune disease.