DNA sequencing demonstrates the importance of jellyfish in life cycles of lepocreadiid trematodes.

Sequence data were combined with morphological analyses to identify two lepocreadiid trematode species from jellyfishes and fishes. Three species of jellyfish were captured within Port Phillip Bay, Australia, and three species of fish that feed on jellyfish were obtained from Moreton Bay (Queensland) and Port Phillip Bay and Portland (Victoria). The digeneans were distributed throughout most parts of the jellyfish. Opechona cf. kahawai Bray & Cribb, 2003 parasitized the scyphozoan jellyfish Aequorea eurodina and the scombrid fish Scomber australasicus. Cephalolepidapedon warehou Bray & Cribb, 2003 parasitized the scyphozoans Pseudorhiza haeckeli and Cyanea annaskala, and the centrolophid fishes Seriolella brama and Seriolella punctata. Intensities ranged from four to 96 in the jellyfish, and one to 30 in the fish. For both trematode species, internal transcribed spacer 2 of ribosomal DNA sequences from mature adults in the fishes matched those from metacercariae from the jellyfish. This is the first record of larval stages of C. warehou and O. cf. kahawai, and the first use of DNA sequencing to identify digenean trematode metacercariae from jellyfish. Three new host records are reported for C. warehou and two for O. cf. kahawai.

Consistency and effect of body position change on measurement of upper and lower esophageal sphincter geometry using impedance planimetry in a canine model.

The EndoFLIP (Endolumenal Functional Lumen Imaging Probe, Crospon Inc, Galway, Ireland) device uses the technique of impedance planimetry to evaluate dimensions and distensibility of the upper and lower esophageal sphincter. The null hypotheses for this study were that EndoFLIP variables would be stable between anesthestic episodes and would not be affected by body position when evaluating the upper and lower esophageal sphincters in healthy dogs. During each of three consecutive general anesthesia episodes administered to eight healthy adult research colony dogs with a standardized protocol, the EndoFLIP catheter was positioned to measure cross-sectional area, intrabag pressure, upper and lower esophageal sphincter length at two different balloon fill volumes (30 and 40 mL) and two body positions (lateral and dorsal recumbency). From these measured variables, a distensibility index was also calculated. Mixed effect analysis of variance was used to evaluate the fixed marginal and interaction effects of anesthesia episode, body position, and balloon volume on measured and calculated variables. For the upper esophageal sphincter significant interactions were present between anesthetic episode and body position for all variables except intrabag pressure; adjusting for body position significant differences were present between anesthetic episodes for all variables except distensibility index; adjusting for anesthetic episode cross-sectional area, intrabag pressure, upper esophageal sphincter length and distensibility index were all affected by body position. For the lower esophageal sphincter distensibility index was the only variable where a significant interaction between anesthesia episode and body position occurred; cross-sectional area, intrabag pressure, and lower esophageal length were not significantly affected by anesthesia episode when adjusting for body position; distensibility index was the only variable significantly affected by body position. Measurements of the geometry of the lower esophageal sphincter as measured by the EndoFLIP device were consistent under conditions of general anesthesia. Similar measurements taken at the upper esophageal sphincter displayed greater variability between anesthetic episodes and were affected to a greater extent by body position. Body position should be standardized in studies using the EndoFLIP to assess geometric and functional characteristics of the upper and lower esophageal sphincters.

Peripheral and central immune cell reservoirs in tissues from asymptomatic cats chronically infected with feline immunodeficiency virus.

Feline immunodeficiency virus (FIV) infection in cats results in life-long viral persistence and progressive immunopathology. We have previously described a cohort of experimentally infected cats demonstrating a progressive decline of peripheral blood CD4+ T-cell over six years in the face of apparent peripheral viral latency. More recently we reported findings from this same cohort that revealed popliteal lymph node tissue as sites for ongoing viral replication suggesting that tissue reservoirs are important in FIV immunopathogenesis during the late asymptomatic phase of infection. Results reported herein characterize important tissue reservoirs of active viral replication during the late asymptomatic phase by examining biopsied specimens of spleen, mesenteric lymph node (MLN), and intestine from FIV-infected and uninfected control cats. Peripheral blood collected coincident with harvest of tissues demonstrated severe CD4+ T-cell depletion, undetectable plasma viral gag RNA and rarely detectable peripheral blood mononuclear cell (PBMC)-associated viral RNA (vRNA) by real-time PCR. However, vRNA was detectable in all three tissue sites from three of four FIV-infected cats despite the absence of detectable vRNA in plasma. A novel in situ hybridization assay identified B cell lymphoid follicular domains as microanatomical foci of ongoing FIV replication. Additionally, we demonstrated that CD4+ leukocyte depletion in tissues, and CD4+ and CD21+ leukocytes as important cellular reservoirs of ongoing replication. These findings revealed that tissue reservoirs support foci of ongoing viral replication, in spite of highly restricted viral replication in blood. Lentiviral eradication strategies will need address tissue viral reservoirs.