Syntaxin 11 is required for NK and CD8+ T‐cell cytotoxicity and neutrophil degranulation

Syntaxin 11 (STX11) controls vesicular trafficking and is a key player in exocytosis. Since Stx11 mutations are causally associated with a familial hemophagocytic lymphohistio‐cytosis, we wanted to clarify whether STX11 is functionally important for key immune cell populations. This was studied in primary cells obtained from newly generated Stx11^?/? mice. Our data revealed that STX11 is not only widely expressed in different immune cells, but also induced upon LPS or IFN‐γ treatment. However, Stx11 deficiency does not affect macrophage phagocytic function and cytokine secretion, mast cell activation, or antigen presentation by DCs. Instead, STX11 selectively controls lymphocyte cytotoxicity in NK and activated CD8⁺ T cells and degranulation in neutrophils. Stx11^?/? NK cells and CTLs show impaired degranulation, despite a comparable activation, maturation and expression of the complex‐forming partners MUNC18–2 and VTI1B. In addition, Stx11^?/? CTLs and NK cells produce abnormal levels of IFN‐γ. Since functional reconstitution rescues the defective phenotype of Stx11^?/? CTLs, we suggest a direct, specific and key role of STX11 in controlling lymphocyte cytotoxicity, cytokine production and secretion. Finally, we show that these mice are a very useful tool for dissecting the role of STX11 in vesicular trafficking and secretion.     

Long-Term Carriage of Vancomycin-Resistant Enterococci in Patients Discharged from Hospitals: a 12-Year Retrospective Cohort Study

Contact precautions are recommended in hospitals to prevent the transmission of vancomycin-resistant enterococci (VRE); however, there is no clear policy for how long patients should be under contact precautions due to a lack of information on the duration of carriage of these organisms. We conducted a retrospective cohort study to understand the duration of carriage of VRE (by screening of a single stool culture) and associated factors among patients who had been identified with VRE infection and/or colonization since the year 2000 at our health facilities. Of the 345 eligible participants, 136 did not respond, 90 declined to participate, and 16 did not send in the required specimens. Of the 103 remaining participants, 13 were found to have current VRE fecal carriage. The proportion of colonized patients fell from 40% (2/5) in the first year to 23.3% (7/30) in year 4. None of the 40 patients who had VRE detected >4 years prior were found to be colonized at the time of the study. The longest duration of detected VRE positivity was 46.5 months. Univariate analysis revealed that recent exposure to any antibiotics (P = 0.016), multiple antibiotics (P = 0.001), amoxicillin-clavulanic acid (P = 0.021), piperacillin-tazobactam (P = 0.007), glycopeptides (P < 0.001), meropenem (P = 0.007), aminoglycosides (P = 0.021), or fluoroquinolones (P = 0.021), being the index case in a clinical specimen (P = 0.016), and recent hospitalization (P < 0.001) were significantly associated with continued carriage on follow-up. In the surviving outpatients, a significant proportion appeared to clear VRE carriage. Our results suggest that in the absence of recent risk factors, such as hospitalization or antibiotic use, patients with a remote history of colonization (>4 years) may no longer require contact isolation precautions.     

A systematic review of randomised controlled trials of interventions reporting outcomes for relatives of people with psychosis

Relatives play a key role in supporting people with psychosis at all stages of recovery, but this can be associated with high levels of distress. Family interventions, with an international evidence base, improve outcomes for service users but little is known about their impact on relatives' outcomes. This review of published evaluations aimed to assess whether family interventions are effective in improving outcomes for relatives of people with psychosis, to identify the key components of effective intervention packages, and to identify methodological limitations to be addressed in future research. Fifty studies were identified which evaluated an intervention to support relatives against a control group, and in which outcomes for the relatives were reported. Thirty (60%) studies showed a statistically significant positive impact of the intervention on at least one relatives' outcome category. Eleven key intervention components were identified across all 50 studies, but there was no evidence that the presence or absence of any of these key components reliably distinguished effective from ineffective interventions. Methodological quality of studies was generally poor with only 11 studies rated as adequate using the Clinical Trial Assessment Measure (CTAM). Recommendations to improve future research include larger samples; better defined interventions and controls; true randomisation and blind assessors; clearly specified primary outcomes; pre-published analysis plans that account appropriately for missing data and clustering of data; a consensus on the most relevant outcomes to assess and valid and reliable measures to do so. Alternative research designs need to be considered to evaluate more recent approaches which focus on family support, personalised to meet individual need, and offered as an integral part of complex clinical services.     

Effect of “Speak Up” educational tools to engage patients in advance care planning in outpatient healthcare settings: A prospective before-after study

BackgroundTools for advance care planning (ACP) are advocated to help ensure patient values guide healthcare decisions. Evaluation of the effect of tools introduced to patients in clinical settings is needed.ObjectiveTo evaluate the effect of the Canadian Speak Up Campaign tools on engagement in advance care planning (ACP), with patients attending outpatient clinics.Patient involvement: Patients were not involved in the problem definition or solution selection in this study but members of the public were involved in development of tools. The measurement of impacts involved patients.MethodsThis was a prospective pre-post study in 15 primary care and two outpatient cancer clinics. The outcome was scores on an Advance Care Planning Engagement Survey measuring Behavior Change Process on 5-point scales and Actions (0?21-point scale) administered before and six weeks after using a tool, with reminders at two or four weeks.Results177 of 220 patients (81%) completed the study (mean 68 years of age, 16% had cancer). Mean Behavior Change Process scores were 2.9 at baseline and 3.5 at follow-up (mean change 0.6, 95% confidence interval 0.5 to 0.7; large effect size of 0.8). Mean Action Measure score was 3.7 at baseline and 4.8 at follow-up (mean change 1.1, 95% confidence interval 0.6–1.5; small effect size of 0.2).Practical valuePublicly available ACP tools may have utility in clinical settings to initiate ACP among patients. More time and motivation may be required to stimulate changes in patient behaviors related to ACP.     

Synonymous Mutations in RNASEH2A Create Cryptic Splice Sites Impairing RNase H2 Enzyme Function in Aicardi–Goutières Syndrome

Aicardi–Goutières syndrome is an inflammatory disorder resulting from mutations in TREX1, RNASEH2A/2B/2C, SAMHD1, or ADAR1. Here, we provide molecular, biochemical, and cellular evidence for the pathogenicity of two synonymous variants in RNASEH2A. Firstly, the c.69G>A (p.Val23Val) mutation causes the formation of a splice donor site within exon 1, resulting in an out of frame deletion at the end of exon 1, leading to reduced RNase H2 protein levels. The second mutation, c.75C>T (p.Arg25Arg), also introduces a splice donor site within exon 1, and the internal deletion of 18 amino acids. The truncated protein still forms a heterotrimeric RNase H2 complex, but lacks catalytic activity. However, as a likely result of leaky splicing, a small amount of full‐length active protein is apparently produced in an individual homozygous for this mutation. Recognition of the disease causing status of these variants allows for diagnostic testing in relevant families.     

Evidence for a role for Galphai1 in mediating weak agonist-induced platelet aggregation in human platelets: reduced Galphai1 expression and defective Gi signaling in the platelets of a patient with a chronic bleeding disorder

We have examined platelet functional responses and characterized a novel signaling defect in the platelets of a patient suffering from a chronic bleeding disorder. Platelet aggregation responses stimulated by weak agonists such as adenosine diphosphate (ADP) and adrenaline were severely impaired. In comparison, both aggregation and dense granule secretion were normal following activation with high doses of collagen, thrombin, or phorbol-12 myristate-13 acetate (PMA). ADP, thrombin, or thromboxane A2 (TxA2) signaling through their respective Gq-coupled receptors was normal as assessed by measuring either mobilization of intracellular calcium, diacylglycerol (DAG) generation, or pleckstrin phosphorylation. In comparison, Gi-mediated signaling induced by either thrombin, ADP, or adrenaline, examined by suppression of forskolin-stimulated rise in cyclic AMP (cAMP) was impaired, indicating dysfunctional Galphai signaling. Immunoblot analysis of platelet membranes with specific antiserum against different Galpha subunits indicated normal levels of Galphai2,Galphai3,Galphaz, and Galphaq in patient platelets. However, the Galphai1level was reduced to 25% of that found in normal platelets. Analysis of platelet cDNA and gDNA revealed no abnormality in either the Galphai1 or Galphai2 gene sequences. Our studies implicate the minor expressed Galphai subtype Galphai1 as having an important role in regulating signaling pathways associated with the activation of alphaIIbbeta3 and subsequent platelet aggregation by weak agonists.