Tuning the endothelial response: differential release of exocytic cargos from Weibel-Palade bodies.

Essentials Endothelial activation initiates multiple processes, including hemostasis and inflammation. The molecules that contribute to these processes are co-stored in secretory granules. How can the cells control release of granule content to allow differentiated responses? Selected agonists recruit an exocytosis-linked actin ring to boost release of a subset of cargo. SUMMARY: Background Endothelial cells harbor specialized storage organelles, Weibel-Palade bodies (WPBs). Exocytosis of WPB content into the vascular lumen initiates primary hemostasis, mediated by von Willebrand factor (VWF), and inflammation, mediated by several proteins including P-selectin. During full fusion, secretion of this large hemostatic protein and smaller pro-inflammatory proteins are thought to be inextricably linked. Objective To determine if secretagogue-dependent differential release of WPB cargo occurs, and whether this is mediated by the formation of an actomyosin ring during exocytosis. Methods We used VWF string analysis, leukocyte rolling assays, ELISA, spinning disk confocal microscopy, high-throughput confocal microscopy and inhibitor and siRNA treatments to demonstrate the existence of cellular machinery that allows differential release of WPB cargo proteins. Results Inhibition of the actomyosin ring differentially effects two processes regulated by WPB exocytosis; it perturbs VWF string formation but has no effect on leukocyte rolling. The efficiency of ring recruitment correlates with VWF release; the ratio of release of VWF to small cargoes decreases when ring recruitment is inhibited. The recruitment of the actin ring is time dependent (fusion events occurring directly after stimulation are less likely to initiate hemostasis than later events) and is activated by protein kinase C (PKC) isoforms. Conclusions Secretagogues differentially recruit the actomyosin ring, thus demonstrating one mechanism by which the prothrombotic effect of endothelial activation can be modulated. This potentially limits thrombosis whilst permitting a normal inflammatory response. These results have implications for the assessment of WPB fusion, cargo-content release and the treatment of patients with von Willebrand disease.

Thrombolysis for stroke in Ireland: increasing access and maintaining safety in a challenging environment.

BACKGROUND: In the setting of a national audit of acute stroke services, we examined the delivery of thrombolytic therapy for ischaemic stroke and whether current practice was achieving safe outcomes and consistent delivery for patients. METHOD: Data obtained from the recent national stroke audit was compared against previous Irish audit, the most recent SSNAP UK stroke audit and the Safe Implementation of Thrombolysis in Stroke-Monitoring Study (SITS-MOST) study. RESULTS: Thrombolysis was provided in 27 acute hospitals throughout Ireland during the period assessed with 82% (22/27) providing 24/7 access, the remaining sites using redirect policies. Decision to thrombolyse was made by stroke trained consultants in 63% (17/27) of units, with general physicians and emergency medicine consultants covering the other units. Thrombolysis rate for non-haemorrhagic stroke was 11% (n = 80/742, CI 95% ±2.23) versus a 1% rate in the 2008 audit. Sites receiving patients through a redirect policy had the highest thrombolysis rate, an average of 24%. Nearly 30% of cases were thrombolysed on the weekend. Eighty-three percent of cases were managed in a stroke unit at some time during admission versus 54% of the national total cases. Thirty-seven percent of patients were ≥80 years old. The mortality rate was 11.3% versus the national mortality rate for non-thrombolysed ischaemic strokes of 10% (p > 0.5), and this is comparable to the SITS-MOST 2007 study 3-month mortality rate of 11.3% (p > 0.5). CONCLUSION: Stroke thrombolysis is being effectively and safely provided in acute stroke services in Ireland despite regular involvement of non-specialist staff. There is still potential to improve thrombolysis rate.

The scaffold protein Ajuba suppresses CdGAP activity in epithelia to maintain stable cell-cell contacts.

Levels of active Rac1 at epithelial junctions are partially modulated via interaction with Ajuba, an actin binding and scaffolding protein. Here we demonstrate that Ajuba interacts with the Cdc42 GTPase activating protein CdGAP, a GAP for Rac1 and Cdc42, at cell-cell contacts. CdGAP recruitment to junctions does not require Ajuba; rather Ajuba seems to control CdGAP residence at sites of cell-cell adhesion. CdGAP expression potently perturbs junctions and Ajuba binding inhibits CdGAP activity. Ajuba interacts with Rac1 and CdGAP via distinct domains and can potentially bring them in close proximity at junctions to facilitate activity regulation. Functionally, CdGAP-Ajuba interaction maintains junctional integrity in homeostasis and diseases: (i) gain-of-function CdGAP mutants found in Adams-Oliver Syndrome patients strongly destabilize cell-cell contacts and (ii) CdGAP mRNA levels are inversely correlated with E-cadherin protein expression in different cancers. We present conceptual insights on how Ajuba can integrate CdGAP binding and inactivation with the spatio-temporal regulation of Rac1 activity at junctions. Ajuba provides a novel mechanism due to its ability to bind to CdGAP and Rac1 via distinct domains and influence the activation status of both proteins. This functional interplay may contribute towards conserving the epithelial tissue architecture at steady-state and in different pathologies.

Antenatal Pertussis Vaccination: Why are General Practitioners Reluctant? A Mixed Methods StudySetting.

Pertussis has a disproportionately higher morbidity and mortality in infants less than 3 months of age. International and national guidelines recommend pertussis vaccination during pregnancy, as a safe and effective way to protect these infants. Antenatal pertussis vaccination uptake rates remain suboptimal, with many health care professionals (HCPs) still not recommending it. The reasons underlying this reluctance on behalf of HCPs have not been fully established. This study aims to evaluate the current practice and attitudes of General Practitioners (GPs) with regard to antenatal pertussis vaccination. An embedded mixed method design was used. The response rate was 41% (n=109). 54% of GPs who responded (n=59) routinely recommend antenatal pertussis vaccination. Safety concerns and a sense of isolation emerged as the major qualitative themes. More safety data, adequate funding from the Health Service Executive (HSE) and support from secondary care may help to increase the GP recommendation rate and enhance vaccination uptake in pregnancy.

The Impact of Blunt Thoracic Aortic Injury on Patients Aged 80 Years or Older.

BACKGROUND: Blunt thoracic aortic injury (BTAI) is rare and associated with significant morbidity and mortality in trauma patients. As the population ages and life expectancy increases, the frequency of this injury will increase in the elderly and thus it behoves us to understand treatment and outcome in this patient population. METHODS: We analysed prospectively collected data of 10 patients > 80 years old with BTAI (Group A) treated among 26,000 trauma patients over a 20-year period in a Level 1 trauma center to investigate BTAI morbidity and mortality. Age, gender, and injurity severity score (ISS) matching was performed to create a case-control study of elderly trauma patients with (Group A) and without BTAI (Group B). RESULTS: Ten elderly trauma patients were found to have BTAI. Five (50%) were males and 5 (50%) were female. The cohort mean age was 86 years (range: 80 to 95). All but one patient (fall injury) were involved in motor vehicle accidents. The mean ISS in group A was 29 ± 12. In group A, 2 (20%) patients (ISS = 36 and 33) succumbed in the emergency department. Six (60%) patients were treated non-operatively and the remaining 2 (20%) patients (88 and 84 years) underwent open aortic repair with patch angioplasty and Dacron interposition grafting. No postoperative paraplegia or stroke related to surgery occurred. Two patients in Group A survived hospitalization and were eventually discharged. Patients in Group B had lower overall LOS, ICU LOS and 30-day mortality rates despite similar ISS. CONCLUSION: Patients aged 80 or older who have experienced BTAI tend to have worse outcomes than those without BTAI regardless of similar ISS. Therefore, because of the low incident of this injury in general and particularly in the elderly, only pooled data from multiple institutions will be able to shed light on the complex issues surrounding treatment decisions in a group of patients with an a priori limited life expectancy.

Delays in the stroke thrombolysis pathway--identifying areas for improvement.

Despite international consensus on the benefits of thrombolysis for ischaemic stroke (IS), it remains underused. Guidelines now recommend a door-to-needle time of 60 minutes. We reviewed the rate and timeliness of thrombolysis for IS at our hospital. 323 stroke patients presented between January 2011 and April 2012.Thirty patients (10.6% of IS) were thrombolysed, mean age was 68.5 years (42 to 88) and 19 patients (63%) were male. Thirty-six patients (12.7% of IS) were not thrombolysed despite arriving within the time-window and symptom resolution was the commonest reason (15 patients; 42%). Despite most thrombolysed patients (42%) presenting to the Emergency Department during daytime working hours, there were delays at each step of the acute care pathway. The mean time for stroke team review was 23 minutes (5-50). The mean door-to-CT and the door-to-needle times were 60 minutes (25-95) and 92 minutes (46-130) respectively. In parallel with national stroke incentives, local audit can highlight barriers to uptake and efficiency within thrombolysis services.

Evaluating symptom outcomes in gastroparesis clinical trials: validity and responsiveness of the Gastroparesis Cardinal Symptom Index-Daily Diary (GCSI-DD).

BACKGROUND: Patient-reported symptom scales are needed to evaluate treatments for gastroparesis. The Gastroparesis Cardinal Symptom Index-Daily Diary (GCSI-DD) was developed to assess daily symptoms of gastroparesis. This study evaluated the validity and responsiveness of the GCSI-DD in patients with gastroparesis. METHODS: Symptomatic patients were started with a new treatment for gastroparesis. Patients completed the GCSI-DD each evening during a baseline week and for 8 weeks of treatment. Responders were defined based on patient and clinician global rating of change. Minimal important differences (MID) were estimated based on baseline to 4 week changes in symptoms scores for small improvements. KEY RESULTS: Of 69 patients participating, 46 had idiopathic, 19 diabetic, and four postfundoplication gastroparesis. Excellent test-retest reliability was seen for GCSI-DD scores, and there were significant correlations between GCSI-DD scores and clinician ratings of symptom severity. Responders to treatment reported improvements in nausea [effect size (ES) = 0.42, P < 0.001], postprandial fullness, ES = 0.83, P < 0.001), bloating (ES = 0.34, P < 0.001), early satiety (ES = 0.53, P < 0.001), but lower responses for upper abdominal pain (ES = 0.29), and vomiting (ES = 0.22; P = 0.119). MIDs were 0.55 for nausea, 0.97 for excessive fullness, 0.63 for bloating, 0.77 for postprandial fullness, and 0.30 for abdominal pain. A composite score of four symptoms (Composite-1; nausea, bloating, excessive fullness, postprandial fullness) had ES of 0.61 and MID of 0.73. Composite-2 score (nausea, early satiety, bloating, abdominal pain) had a lower ES of 0.47. CONCLUSIONS & INFERENCES: Symptoms of early satiety, nausea, postprandial fullness, and bloating were responsive to treatment for gastroparesis. A composite of these symptoms also demonstrates validity and responsiveness to treatment for gastroparesis, and may represent an acceptable endpoint for evaluating the effectiveness of medical treatments in clinical trials for gastroparesis.

Regional anaesthesia and pain management.

Despite recent advances in analgesia delivery techniques and the availability of new analgesic agents with favourable pharmacokinetic profiles, current evidence suggests that postoperative pain continues to be inadequately managed, with the proportion of patients reporting severe or extreme postoperative pain having changed little over the past decade. Regional techniques are superior to systemic opioid agents with regards to analgesia profile and adverse effects in the context of general, thoracic, gynaecological, orthopaedic and laparoscopic surgery. Outcome studies demonstrate that regional analgesic techniques also reduce multisystem co-morbidity and mortality following major surgery in high risk patients. This review will discuss the efficacy of regional anaesthetic techniques for acute postoperative analgesia, the impact of regional block techniques on physiological outcomes, and the implications of acute peri-operative regional anaesthesia on chronic (persistent) postoperative pain.

The effects of different analgesic regimens on transcutaneous CO2 after major surgery.

Ventilatory impairment may be detected by a rise in transcutaneous carbon dioxide levels (PtcCO(2)). This observational study assessed the clinical utility of PtcCO(2) monitoring in the postoperative period, and quantified the effect of different peri-operative analgesic regimens on postoperative respiratory function. Following pre-operative baseline PtcCO(2) recording, continuous PtcCO(2) monitoring was performed in 30 patients after major colorectal surgery for up to 24 h. Mean postoperative values of PtcCO(2) were 1.3 kPa (95% CI 1.0-1.5) higher than pre-operative values (p < 0.001). Patients receiving intravenous opioid patient controlled analgesia had a significantly higher elevation in postoperative PtcCO(2) compared to patients receiving epidural infusion analgesia, 1.8 kPa (CI 1.5-2.1) vs 0.7 kPa (CI 0.5-0.9) respectively (p < 0.001). The mean rise in PtcCO(2) following a single intravenous bolus of morphine delivered via PCA was 0.05 kPa (SEm 0.01), peaking at 12 min post-dose. The transcutaneous capnometer successfully recorded data for 98% of the total time it was applied to patients.

Validation of the revised Patient Perception of Migraine Questionnaire (PPMQ-R): measuring satisfaction with acute migraine treatment in clinical trials.

This study was aimed to evaluate in clinical trial settings the psychometric properties of the revised Patient Perception of Migraine Questionnaire (PPMQ-R), a satisfaction measure for acute migraine treatment. The PPMQ-R was administered 24 h post dosing in 1304 migraineurs randomized to two identical Phase 3, single-attack trials. Reliability, concurrent and construct validity and known-groups validity were evaluated using Cronbach's alpha, Pearson correlations and analysis of variance, respectively. PPMQ-R scale and Total scores (Efficacy, Functionality and Ease of use) showed very good internal consistency reliability (alpha 0.84-0.99). Efficacy, Functionality and Total PPMQ-R scores showed large, inverse relationships with migraine pain severity, number of migraine symptoms and work ability (r = -0.62 to -0.75; all P < 0.0001). All scales discriminated among migraine pain severity levels (all P < 0.001). The PPMQ-R has sufficient evidence of validity and reliability for measuring patient satisfaction, an important benchmark of quality and effective care.

Speciation in the highlands of Mexico: genetic and phenotypic divergence in the Mexican jay (Aphelocoma ultramarina).

The pine-oak woodlands of the Mexican highlands harbour significant biological diversity, yet little is known about the evolutionary history of organisms inhabiting this region. We assessed genetic and phenotypic differentiation in 482 individuals representing 27 populations of the Mexican jay (Aphelocoma ultramarina) - a widespread bird species of the Mexican highlands - to test whether populations in the central and northern Mexican sierras display discrete breaks between groups, which would be consistent with a role for the different mountain chains in divergence and speciation. We found abrupt breaks in mitochondrial DNA (mtDNA; ND2 and control region) delineating four major genetic groups found in the Sierra Madre Occidental, Sierra Madre Oriental, southern Central Plateau (Bajio), and Transvolcanic Belt. These mtDNA groups were largely corroborated by data from nuclear microsatellites and phenotypic data, except that clades from the Central Plateau and Sierra Madre Oriental showed clinal change in these data sets. Uncertainty about the mutation rate for our mitochondrial markers warrants considerable caution with regard to estimating divergence times, but the major genetic groups appear to have split before the most extreme period of glacial cycling that marked the last 0.7 million years and after Mexico's period of major mountain formation. The fact that some genetic breaks do not coincide with well-known geographic barriers suggests a role for ecology in divergence and speciation, and we discuss implications for taxonomy and conservation.