Olfactory attractiveness of flowering plants to the parasitoid Microplitis mediator: potential implications for biological control

In agricultural landscapes, the lack of floral nectar can be a major difficulty for nectar feeding parasitoids. This problem can be reduced by the addition of suitable wildflowers. To date, flowers have mainly been studied in terms of effects on parasitoid fitness, not taking into account the essential role of flower attractiveness for foraging parasitoids. This study experimentally tested the olfactory attractiveness of five wildflowers (bishop's weed, cornflower, buckwheat, candytuft, and oregano) to the parasitoid Microplitis mediator (Haliday) (Hymenoptera: Braconidae). We conducted choice experiments in a Y-tube olfactometer to test the attractiveness of flowers against air, and relative attractiveness in paired choice tests. Our results showed that all the flowers were highly attractive and that in paired choice tests cornflower and candytuft were equally attractive and more attractive than buckwheat. These results indicate that M. mediator has evolved innate preferences that could be effectively exploited in biological contro

Refreshing medical students' intravenous-cannulation skills: a blinded observer three-arm randomised comparison of mental imagery, part-task trainer simulation and written instructions.

INTRODUCTION Intravenous cannulation is a core competence in medicine, but is considered challenging to learn. This study investigates the effectiveness of three educational strategies used to refresh the intravenous cannulation skills of first-year medical students: mental imagery, part-task trainer simulation and written instructions. MATERIALS AND METHODS In this single-centre randomised controlled trial, first-year medical students were assigned to one of three different refresher tutorials on intravenous cannulation. Six months after their compulsory 4 hour instructor-led intravenous-cannulation course, each student was randomised to a 6 min self-learning tutorial: a mental imagery audioguide session, hands-on intravenous cannulation on a part-task trainer or reading written instructions.Immediately after the refresher tutorials, trained evaluators who were blinded to the randomised group assessed the students' performance. Each evaluator completed a 15-item standardised checklist in an Objective Structured Clinical Examination (OSCE) station for intravenous cannulation. We performed a descriptive analysis of the data and a one-way analysis of variance. Additionally, we investigated the influence of previous intravenous cannulation experience on the total OSCE score. RESULTS AND DISCUSSION On analysing the 309 students' results, we did not find differences in the total rating of the performance (in percentage) between the three groups at the OSCE station (mental imagery group: 72.0%±17.9%; part-task trainer group: 74.4%±15.6%; written instructions group: 69.9%±16.6%, p=0.158). Multiple linear regression showed a small but statistically significant effect of students' previous intravenous cannulation experience on OSCE performance. With the same outcome, written instructions and mental imagery had a better return on effort, compared with resource-intensive hands-on training with part-task trainers. CONCLUSION A single, short refresher seems to have a limited effect on intravenous-cannulation skills in first-year medical students. Less resource-intensive interventions, such as written instructions or mental imagery, are effective compared with hands-on part-task trainer simulation for refreshing this simple but important skill. TRIAL REGISTRATION NUMBER AEARCTR-0008043

Impact of early-onset seizures on grading and outcome in patients with subarachnoid hemorrhage

OBJECT After subarachnoid hemorrhage (SAH), seizure occurs in up to 26% of patients. The impact of seizure on outcome has been studied, yet its impact on grading is unknown. The authors evaluated the impact of early-onset seizures (EOS) on grading of spontaneous SAH and on outcome. METHODS This retrospective analysis included consecutive patients with SAH who were treated at the NeuroCenter, Inselspital, University Hospital Bern, Switzerland, between January 2005 and December 2010. Demographic data, clinical data, and reports of EOS were recorded. The EOS were defined as seizures occurring within 24 hours after ictus. Patients were graded according to the World Federation of Neurosurgical Societies (WFNS) scale pre- and postresuscitation and dichotomized into good (WFNS I-III) and poor (WFNS IV-V) grades. Outcome was assessed at 6 months by using the modified Rankin Scale (mRS); an mRS score of 0-3 was considered a good outcome and an mRS score of 4-6 was considered a poor outcome. RESULTS Forty-one of 425 patients with SAH had EOS. Twenty-seven of those 41 patients (65.9%) had a poor WFNS grade. Twenty-eight (68.3%) achieved a good outcome, 11 (26.8%) had a poor outcome, and 2 (4.9%) were lost to followup. Early-onset seizures were proven in 9 of 16 electroencephalograms. The EOS were associated with poor WFNS grade (OR 2.81, 97.5% CI 1.14-7.46; p = 0.03) and good outcome (OR 4.01, 97.5% CI 1.63-10.53; p = 0.03). Increasing age, hydrocephalus, intracerebral hemorrhage, and intraventricular hemorrhage were associated with poor WFNS grade, whereas only age, intracerebral hemorrhage (p < 0.001), and poor WFNS grade (p < 0.001) were associated with poor outcome. CONCLUSIONS Patients with EOS were classified significantly more often in a poor grade initially, but then they significantly more often achieved a good outcome. The authors conclude that EOS can negatively influence grading. This might influence decision making for the care of patients with SAH, so grading of patients with EOS should be interpreted with caution

Reconsidering the logic of World Federation of Neurosurgical Societies grading in patients with severe subarachnoid hemorrhage

OBJECT Current data show a favorable outcome in up to 50% of patients with World Federation of Neurosurgical Societies (WFNS) Grade V subarachnoid hemorrhage (SAH) and a rather poor prediction of worst cases. Thus, the usefulness of the current WFNS grading system for identifying the worst scenarios for clinical studies and for making treatment decisions is limited. One reason for this lack of differentiation is the use of "negative" or "silent" diagnostic signs as part of the WFNS Grade V definition. The authors therefore reevaluated the WFNS scale by using "positive" clinical signs and the logic of the Glasgow Coma Scale as a progressive herniation score. METHODS The authors performed a retrospective analysis of 182 patients with SAH who had poor grades on the WFNS scale. Patients were graded according to the original WFNS scale and additionally according to a modified classification, the WFNS herniation (hWFNS) scale (Grade IV, no clinical signs of herniation; Grade V, clinical signs of herniation). The prediction of poor outcome was compared between these two grading systems. RESULTS The positive predictive values of Grade V for poor outcome were 74.3% (OR 3.79, 95% CI 1.94-7.54) for WFNS Grade V and 85.7% (OR 8.27, 95% CI 3.78-19.47) for hWFNS Grade V. With respect to mortality, the positive predictive values were 68.3% (OR 3.9, 95% CI 2.01-7.69) for WFNS Grade V and 77.9% (OR 6.22, 95% CI 3.07-13.14) for hWFNS Grade V. CONCLUSIONS Limiting WFNS Grade V to the positive clinical signs of the Glasgow Coma Scale such as flexion, extension, and pupillary abnormalities instead of including "no motor response" increases the prediction of mortality and poor outcome in patients with severe SAH

Reconsidering the logic of World Federation of Neurosurgical Societies grading in patients with severe subarachnoid hemorrhage.

OBJECT Current data show a favorable outcome in up to 50% of patients with World Federation of Neurosurgical Societies (WFNS) Grade V subarachnoid hemorrhage (SAH) and a rather poor prediction of worst cases. Thus, the usefulness of the current WFNS grading system for identifying the worst scenarios for clinical studies and for making treatment decisions is limited. One reason for this lack of differentiation is the use of "negative" or "silent" diagnostic signs as part of the WFNS Grade V definition. The authors therefore reevaluated the WFNS scale by using "positive" clinical signs and the logic of the Glasgow Coma Scale as a progressive herniation score. METHODS The authors performed a retrospective analysis of 182 patients with SAH who had poor grades on the WFNS scale. Patients were graded according to the original WFNS scale and additionally according to a modified classification, the WFNS herniation (hWFNS) scale (Grade IV, no clinical signs of herniation; Grade V, clinical signs of herniation). The prediction of poor outcome was compared between these two grading systems. RESULTS The positive predictive values of Grade V for poor outcome were 74.3% (OR 3.79, 95% CI 1.94-7.54) for WFNS Grade V and 85.7% (OR 8.27, 95% CI 3.78-19.47) for hWFNS Grade V. With respect to mortality, the positive predictive values were 68.3% (OR 3.9, 95% CI 2.01-7.69) for WFNS Grade V and 77.9% (OR 6.22, 95% CI 3.07-13.14) for hWFNS Grade V. CONCLUSIONS Limiting WFNS Grade V to the positive clinical signs of the Glasgow Coma Scale such as flexion, extension, and pupillary abnormalities instead of including "no motor response" increases the prediction of mortality and poor outcome in patients with severe SAH

Lymphotoxin β receptor signaling promotes development of autoimmune pancreatitis

BACKGROUND & AIMS:: Little is known about the pathogenic mechanisms of autoimmune pancreatitis (AIP), an increasingly recognized, immune-mediated form of chronic pancreatitis. Current treatment options are limited and disease relapse is frequent. We investigated factors that contribute to development of AIP and new therapeutic strategies. METHODS:: We used quantitative PCR, immunohistochemical and ELISA analyses to measure expression of cytokines and chemokines in tissue and serum samples from patients with and without AIP. We created a mouse model of human AIP by overexpressing LTα and β specifically in acinar cells ( Ela1-LTab mice). RESULTS:: mRNA levels of lymphotoxin (LT) αandβ were increased in pancreatic tissues from patients with AIP, compared with controls, and expression of chemokines ( CXCL13, CCL19, CCL21, CCL1 and BAFF) was increased in pancreatic and serum samples from patients. Upregulation of these factors was not affected by corticosteroid treatment. Acinar-specific overexpression of LTαβ (Ela1-LTαβ) in mice led to an autoimmune disorder with various features of AIP. Chronic inflammation developed only in the pancreas but was sufficient to cause systemic autoimmunity. Acinar-specific overexpression of LTαβ did not cause autoimmunity in mice without lymphocytes(Ela1-LTab/Rag1(-/-)); moreover lack of pro-inflammatory monocytes (Ela1-LTab/Ccr2-/-) failed to prevent AIP but prevented early pancreatic tissue damage. Administration of corticosteroids reduced pancreatitis but did not affect production of autoantibodies, such as anti-pancreatic secretory trypsin inhibitor in Ela1-LTab mice. In contrast, inhibition of LTβR signaling reduced chemokine expression, renal immune-complex deposition, and features of AIP in Ela1-LTab mice. CONCLUSIONS:: Overexpression of LT α βspecifically in acinar cells of mice causes features of AIP. Reagents that neutralize LT β R ligands might be used to treat patients with AIP