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Some parasites manipulate their host's phenotype to enhance predation rates by the next host in the parasite's life cycle. Our understanding of this parasite-increased trophic transmission is often stymied by study-design challenges. A recurring difficulty has been obtaining uninfected hosts with a coevolutionary history with the parasites, and conducting experimental infections that mimic natural processes. In 1996, Lafferty and Morris provided what has become a classic example of parasite-increased trophic transmission; they reported a positive association between the intensity of a brain-infecting trematode (Euhaplorchis californiensis) in naturally infected California killifish (Fundulus parvipinnis) and the frequency of conspicuous behaviors, which was thought to explain the documented 10-30× increase in predation by the final host birds. Here, we address the primary gap in that study by using experimental infections to assess the causality of E. californiensis infection for increased conspicuous behaviors in F. parvipinnis. We hatched and reared uninfected F. parvipinnis from a population co-occurring with E. californiensis, and infected them 1-2 times/week over half their life span with E. californiensis and a small cyathocotylid trematode (SMCY) that targets the host's muscle tissue. At 3 time points throughout the hosts' lives, we quantified several conspicuous behaviors: contorting, darting, scratching, surfacing, and vertical positioning relative to the water's surface. Euhaplorchis californiensis and SMCY infection caused 1.8- and 2.5-fold overall increases in conspicuous behaviors, respectively. Each parasite was also associated with increases in specific conspicuous behaviors, particularly 1.9- and 1.4-fold more darting. These experimental findings help solidify E. californiensis-F. parvipinnis as a classic example of behavioral manipulation. Yet our findings for E. californiensis infection-induced behavioral change were less consistent and strong than those previously documented. We discuss potential explanations for this discrepancy, particularly the idea that behavioral manipulation may be most apparent when fish are actively attacked by predators. Our findings concerning the other studied trematode species, SMCY, highlight that trophically transmitted parasites infecting various host tissues are known to be associated with conspicuous behaviors, reinforcing calls for research examining how communities of trophically transmitted parasites influence host behavior., (© American Society of Parasitologists 2023.)

ABVD (Adriamycin, bleomycin, vinblastine, dacarbazine) with or without radiation has been the standard treatment for limited-stage Hodgkin lymphoma (HL) but carries risks of bleomycin lung injury and radiation toxicity. Brentuximab vedotin (BV) is approved with AVD for stage III-IV HL, but carries increased risks of peripheral neuropathy (PN) and neutropenic fever, likely due to overlapping toxicity between BV and vinblastine. We therefore evaluated BV in combination with AD for 4 or 6 cycles based on interim positron emission tomography response. Thirty-four patients with nonbulky stage I-II HL were enrolled. Risk was early favorable in 53% and unfavorable in 47%. The overall and complete response rates (CRRs) were 100% and 97%, respectively, with a 5-year progression-free survival (PFS) of 91%. No differences in outcome were observed based on stage (I vs II) or risk status (early favorable vs unfavorable). The most common adverse events were nausea (85%), peripheral sensory neuropathy (59%), and fatigue (56%). There were no cases of grade-4 neutropenia or neutropenic fever, and no patient received granulocyte-colony stimulating factor. Most cases of PN were grade 1, and no patient experienced grade ≥3 PN. BV-AD produced a high CRR and durable PFS with most patients requiring 4 cycles of therapy. Compared with BV-AVD, the toxicity profile appeared improved, with predominantly grade 1 reversible PN and no case of grade 4 neutropenia or neutropenic fever. This regimen warrants further study in HL and may serve as a backbone for the addition of novel agents. This trial is registered on clinicaltrials.gov (NCT02505269)., (© 2023 by The American Society of Hematology. Licensed under Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0), permitting only noncommercial, nonderivative use with attribution. All other rights reserved.)

Background: Evidence suggests that healthcare professionals feel inadequately equipped to manage ethical issues that arise, resulting in ethics-related stress. Clinical ethics consultation, and preventive ethics strategies, have been described as ways to decrease ethics-related stress, however information is limited regarding specific sources of ethical concern., Methods: The purpose of this study was to conduct a retrospective, longitudinal analysis of a comprehensive database of ethics consultations, at a major academic medical center in the Northeast United States in order to: (1) Discern major sources of ethical concern, (2) Evaluate how these have changed over time in their content and frequency, (2a) Evaluate trends in nurse versus physician-initiated requests., Results: Six major reasons for requesting an ethics consult were identified: Conflict Over Goals of Care, Decisional Capacity, Withholding/Withdrawing Treatment, Proxy Decision Making, Communication, and Behavior. Themes were operationally defined by the study team. An increase in requests related to Conflict Over Goals of Care (β = 0.7, 95% CI = 0.2-1.2, p  = 0.008) and Discharge Planning (β = 2.2, 95% CI = 1.4-3.1, p  < 0.001), and a trend toward increased number of consults for behavior-related consults from nurses (median 6.5% versus 2.3%, p  = 0.07) were noted. Nurses were significantly more likely than physicians to request ethics consultation for Communication (yearly median 10.4% of cases vs 1.3% of cases, p  = 0.01), whereas, physicians were significantly more likely to request ethics consultation for Proxy Decision-Making than nurses (yearly median 26.0% of cases vs 13.0%, p  = 0.005) and for Decision-Making Capacity (yearly median 7.5% of cases vs 4.0%, p  = 0.04)., Conclusions: This study revealed several noteworthy and previously unidentified trends in consultation requests, and several important distinctions between the sources of ethical concern nurses identify versus those physicians identify. These findings can be used to develop future preventive-ethics frameworks.

Some parasite species alter the behavior of intermediate hosts to promote transmission to the next host in the parasite's life cycle. This is the case for Euhaplorchis californiensis , a brain-encysting trematode parasite that causes behavioral changes in the California killifish ( Fundulus parvipinnis ). These manipulations increase predation by the parasite's final host, piscivorous marsh birds. The mechanisms by which E. californiensis achieves this manipulation remain poorly understood. As E. californiensis cysts reside on the surface of the killifish's brain, discerning regional differences in parasite distribution could indicate mechanisms for host control. In this study, we developed a method for repeated experimental infections. In addition, we measured brain-region specific density using a novel methodology to locate and quantify parasite infection. We show that E. californiensis cysts are non-randomly distributed on the fish brain, aggregating on the diencephalon/mesencephalon region (a brain area involved in controlling reproduction and stress coping) and the rhombencephalon (an area involved in controlling locomotion and basal physiology). Determining causal mechanisms behind this pattern of localization will guide future research examining the neurological mechanisms of parasite-induced host manipulation. These findings suggest that parasites are likely targeting the reproductive, monoaminergic, and locomotor systems to achieve host behavioral manipulation.

Background: Nurses in the cardiac intensive care unit often attend professional education opportunities. However, it is difficult to share this information among nursing staff. Varying schedules, different shifts, and patient acuity limit the amount of time available for peer-to-peer sharing of educational information. A review of the literature revealed scant research on blogging for peer-to-peer education in general and particularly in nursing., Objectives: To explore nurses' perception of the effectiveness of using a blog as a forum to provide peer-to-peer sharing of relevant professional education., Methods: Using a simple, free blogging website, the unit's nursing practice council developed a private blog for educational information sharing among the nursing staff. An online survey was administered to the unit's staff 15 months after the blog was implemented., Results: Most respondents indicated that they thought the blog is an effective way to share professional education (86%), keeps them abreast of evidence-based practice (81%), and has led to practice change (59%). Nearly 80% of respondents agreed that they are more likely to attend professional conferences, and 62% would consider contributing blog posts., Conclusion: The survey results suggest that blogging may be an effective method of peer-to-peer sharing of education, although more rigorous research is required in this area., (©2017 American Association of Critical-Care Nurses.)