A Digenean Metacercaria (Apophallus sp.) and a Myxozoan (Myxobolus sp.) Associated with Vertebral Deformities in Cyprinid Fishes from the Willamette River, Oregon

A high prevalence of vertebral deformities has been observed in various fishes, especially cyprinids, from certain regions of the Willamette River for many years. One proposed source of these deformities is exposure to toxicants. Histological evaluation of affected chiselmouth Acrocheilus alutaceus revealed that all lesions associated with vertebrae were associated with metacercariae of digenean trematodes. Approximately half of the northern pikeminnow Ptychocheilus oregonensis had infections in which metacercariae were associated with these lesions. Metacercariae were also associated with vertebral lesions in three of four affected peamouth Mylocheilus caurinus. Many metacercariae that were present within the vertebral bodies were associated with bony dysplasia and bony proliferation in all three species. We also evaluated the association of the metacercariae with the vertebral deformities, using intact fish that had been cleared with trypsin. Fish from the affected regions had a much higher prevalence of metacercariae and deformities and a greater abundance of metacercariae than those in the reference site. Chiselmouths had more deformities and metacercariae than northern pikeminnow. In all fish species, 77% of deformities were directly associated with metacercariae; in chiselmouths, about 95% of the deformities exhibited this relationship. Two types of metacercariae were identified in affected fish: Apophallus sp. (Heterophyidae) and a neascus type (Strigeidida). The Apophallus sp. appeared to be more closely associated with the skeleton deformities. A Myxobolus sp. morphologically similar to M. cyprini was also associated with the vertebral lesions in about 50% of the northern pikeminnow and 5% of the chiselmouths. Intact plasmodia were found in somatic muscle, and lesions containing free spores were often located at bone surfaces. This survey demonstrates that metacercariae (probably Apophallus sp.) and a Myxobolus sp. are major causes of the vertebral deformities seen in cyprinid fishes from certain regions of the Willamette River.This is the publisher’s final pdf. The published article is copyrighted by the American Fisheries Society and can be found at: http://www.tandfonline.com/toc/uahh20/current#.UgvTRHfAF8F

Mycobacterium abscessus-Induced Granuloma Formation Is Strictly Dependent on TNF Signaling and Neutrophil Trafficking

Mycobacterium abscessus is considered the most common respiratory pathogen among the rapidly growing non-tuberculous mycobacteria. Infections with M. abscessus are increasingly found in patients with chronic lung diseases, especially cystic fibrosis, and are often refractory to antibiotic therapy. M. abscessus has two morphotypes with distinct effects on host cells and biological responses. The smooth (S) variant is recognized as the initial airway colonizer while the rough (R) is known to be a potent inflammatory inducer associated with invasive disease, but the underlying immunopathological mechanisms of the infection remain unsolved. We conducted a comparative stepwise dissection of the inflammatory response in S and R pathogenesis by monitoring infected transparent zebrafish embryos. Loss of TNFR1 function resulted in increased mortality with both variants, and was associated with unrestricted intramacrophage bacterial growth and decreased bactericidal activity. The use of transgenic zebrafish lines harboring fluorescent macrophages and neutrophils revealed that neutrophils, like macrophages, interact with M. abscessus at the initial infection sites. Impaired TNF signaling disrupted the IL8-dependent neutrophil mobilization, and the defect in neutrophil trafficking led to the formation of aberrant granulomas, extensive mycobacterial cording, unrestricted bacterial growth and subsequent larval death. Our findings emphasize the central role of neutrophils for the establishment and maintenance of the protective M. abscessus granulomas. These results also suggest that the TNF/IL8 inflammatory axis is necessary for protective immunity against M. abscessus and may be of clinical relevance to explain why immunosuppressive TNF therapy leads to the exacerbation of M. abscessus infections

Enlivening a Community of Authentic Scholarship

Background: Critical and engaged qualitative scholarship depends on high-quality graduate training. The need to reexamine graduate student mentorship has become particularly pressing, given the high level of mental health distress experienced by students. It is unclear whether mentorship emerging within the student–advisor relationship is sufficient to ensure comprehensive mentorship. Innovative, experiential pedagogical approaches that integrate emotional and intellectual aspects are limited but may play a vital role in mentorship. There is a critical need to develop and study creative mentorship initiatives for emerging qualitative scholars. Methods: This study used interpretive description methodology and a community of practice theoretical framework to describe a faculty-mentored experience for graduate nursing students at the 2016 Qualitative Health Research Conference (FM-QHR) hosted by the International Institute for Qualitative Methodology. Participants completed written journals elucidating their experiences throughout FM-QHR. The textual data were analyzed using a constant comparative group analysis process, leading to the development of salient and interconnected themes. Results: Six graduate students and four faculty mentors submitted journals. Three interrelated themes articulate how this FM-QHR initiative enlivened a community of authentic scholarship: Questioning the Academic Self: Unvoiced Experiences of Angst, Uncertainty, and Fear ; Cocreating Authentic Community through Shared Vulnerability ; and Generative and Emergent Empowerment . Conclusion: These findings provide compelling insights into the importance of assisting students to navigate the emotional experiences that are a part of qualitative graduate training. Relational, mentorship initiatives hold potential to not only alleviate emotional distress but also support student empowerment, socialization, and entrance into a community of international qualitative researchers