Nuclear small-subunit ribosomal RNA gene-based characterization, molecular phylogeny and PCR detection of the Neoparamoeba from western Long Island Sound lobster

Author Posting. © National Shellfisheries Association, 2005. This article is posted here by permission of National Shellfisheries Association for personal use, not for redistribution. The definitive version was published in Journal of Shellfish Research 24 (2005): 719-731, doi:10.2983/0730-8000(2005)24[719:NSRRGC]2.0.CO;2.Western Long Island Sound (LIS) lobsters collected by trawl surveys, lobstermen and coastal residents during 2000 to 2002 were identified histologically as infected with a parasome-containing amoeba. Primers to conserved SSU rRNA sequences of parasome-containing amoebae and their nonparasome-containing relatives were used to amplify overlapping SSU rRNA fragments of the presumptive parasite from gill, antenna, antennal gland and ventral nerve cord of infected lobsters. The consensus sequence constructed from these fragments had 98% or greater nucleotide sequence identity with SSU rRNA gene sequences of strains of Neoparamoeba pemaquidensis and associated with high confidence in distance- and parsimony-based phylogenetic analyses with strains of Neoparamoeba pemaquidensis and not members of the family Paramoebidae, e.g., Paramoeba eilhardi. Primers designed to SSU rRNA sequences of the lobster amoeba and other paramoebid/vexilliferid amoebae were used in a nested polymerase chain reaction (PCR) protocol to test DNA extracted from formalin-fixed paraffin-embedded tissues of lobsters collected during the 1999 die-off, when this amoeba initially was identified by light and electron microscopy and reported to be a paramoeba of the genera Paramoeba or Neoparamoeba (Mullen et al. 2004). All sequences amplified from 1999 lobsters, with the exception of one, had 98% to 99% identity to each other, and the 1999 PCR product consensus had 98% identity to Neoparamoeba pemaquidensis strains CCAP 1560/4 (AF371969.1) and 1560/5 (AF371970.1). Molecular characterization of the amoeba from western LIS lobsters by direct amplification circumvents a collective inability to culture the organism in vitro, provides insight into the molecular epidemiology of neoparamoebiasis in American lobster, and allows for PCR-based detection of infected lobsters for future research and diagnostics.Funding for this work was provided by the Connecticut Department of Environmental Protection under Long Island Sound Research Fund Grant No. CWF 333-R to S. Frasca; and by the Connecticut Sea Grant College Program, Grants No. LR/LR-4 to R. Gast and No. LR/LR-5 to P. Gillevet and C. O’Kelly, through the US Department of Commerce, National Oceanic and Atmospheric Administration (NOAA), Award NA16RG1364

The Joint Influence of Intra- and Inter-Team Learning Processes on Team Performance: A Constructive or Destructive Combination?

In order for teams to build a shared conception of their task, team learning is crucial. Benefits of intra-team learning have been demonstrated in numerous studies. However, teams do not operate in a vacuum, and interact with their environment to execute their tasks. Our knowledge of the added value of inter-team learning (team learning with external parties) is limited. Do both types of team learning compete over limited resources, or do they form a synergistic combination? We aim to shed light on the interplay between intra- and inter-team learning in relation to team performance, by including adaptive and transformative sub-processes of intra-team learning. A quantitative field study was conducted among 108 university teacher teams. The joint influence of intra- and inter-team learning as well as structural (task interdependence) and cultural (team efficacy) team characteristics on self-perceived and externally rated team performance were explored in a path model. The results showed that adaptive intra-team learning positively influenced self-perceived team performance, while transformative intra-team learning positively influenced externally rated team performance. Moreover, intra-team and inter-team learning were found to be both a constructive and a destructive combination. Adaptive intra-team learning combined with inter-team learning led to increased team performance, while transformative intra-team learning combined with inter-team learning hurt team performance. The findings demonstrate the importance of distinguishing between both the scope (intra- vs. inter-team) and the level (adaptive vs. transformative) of team learning in understanding team performance

Fusion between hematopoietic and epithelial cells in adult human intestine.

Following transplantation of hematopoietic lineage cells, genetic markers unique to the transplanted cells have been detected in non-hematopoietic recipient cells of human liver, vascular endothelium, intestinal epithelium and brain. The underlying mechanisms by which this occurs are unclear. Evidence from mice suggests it is due in part to fusion between cells of hematopoietic and non-hematopoietic origins; however, direct evidence for this in humans is scant. Here, by quantitative and statistical analysis of X- and Y-chromosome numbers in epithelial and non-epithelial intestinal cells from gender-mismatched hematopoietic cell transplant patients, we provide evidence that transplanted cells of the hematopoietic lineage incorporate into human intestinal epithelium through cell fusion. This is the first definitive identification of cell fusion between hematopoietic cells and any epithelial cell type in humans, and provides the basis for further understanding the physiological and potential pathological consequences of cell fusion in humans

Midterm clinical and magnetic resonance imaging follow-up of large and giant carotid artery aneurysms after therapeutic carotid artery occlusion

OBJECTIVE: The purpose of this study was to evaluate aneurysm size and clinical symptoms midterm after therapeutic carotid artery occlusion in 39 patients with large or giant carotid artery aneurysms. METHODS: Between January 1996 and August 2004, 39 patients with large or giant carotid artery aneurysms were treated with therapeutic carotid artery occlusion and had clinical and magnetic resonance imaging follow-up of at least 3 months (mean, 35.9 mo; median, 29 mo; range, 3-107 mo; 117 patient-yr). Initial clinical presentation was mass effect caused by the aneurysm in 32 (82%) of the 39 patients. Three patients presented with subarachnoid hemorrhage and one presented with epistaxis; two aneurysms were an incidental finding and one was additional to another ruptured aneurysm. RESULTS: There were no early or late complications of therapeutic carotid artery occlusion. All aneurysms seemed to have thrombosed completely after carotid artery occlusion as observed on early and late magnetic resonance imaging and magnetic resonance angiographic follow-up studies. At the time of the most recent magnetic resonance imaging follow-up study, 29 (74%) of the 39 aneurysms involuted totally, two aneurysms decreased to 25% of the original diameter, two aneurysms decreased to 50%, and five aneurysms decreased to 75%. Two aneurysms remained unchanged in size after 49 and 58 months, respectively. At the most recent clinical follow-up evaluation, symptoms of mass effect were cured in 19 (60%), improved in 10 (31%), and remained unchanged in three (9%) of the 32 patients. CONCLUSION: Therapeutic carotid artery occlusion was a simple, safe, and effective treatment for large and giant carotid artery aneurysms. Almost all aneurysms involute completely or substantially decrease in size. Alleviation of symptoms of mass effect was achieved in most patient

Differentiation status of cells with abnormal sex-karyotypes.

<p><b>(</b>A) FABP2/IFABP expression in a control and (B) transplant patient sample with an example of an XXY cell. Brackets indicate differentiated (high Fabp2/Ifabp expression, black brackets) and undifferentiated (low Fabp2/Ifabp expression, gray brackets) regions of epithelium within each sample. (C) Enlarged view of boxed region from <i>B</i>, in an adjacent tissue section stained for Lamin B1.(D) Enlarged view of boxed region from panel C, showing X- (green) and Y- (red) chromosomes and Lamin B1 (white). Arrowhead indicates the same nucleus in panels C and D. Dashed lines indicate boundaries of epithelial and non-epithelial compartments.</p

Frequency of nuclei with 2 or 3 X-chromosomes.

<p>Percent of Y-chromosome-positive nuclei with two or three X-chromosomes, observed in epithelial (epi) and non-epithelial (non-epi) compartments of normal male and male-into-female gender mismatched bone marrow transplant patients (transplant). *, p = 0.0016, Fisher's exact test.</p

Epithelial compartmentalization and sex-karyotyping of intestinal cells.

<p>(A) Hematoxylin and Eosin stained intestinal biopsy; epithelial compartment is labeled. (B) Adjacent tissue section to that from panel A stained for X- (green) and Y- (red) chromosomes and Lamin B1 (white). Arrows indicate Y-chromosome-positive epithelial cells and the arrowhead points to a Y-chromosome-positive non-epithelial cell. Inset shows a sub-region stained for cytokeratin (blue); arrows and arrowhead serve as positional references. (C) Enlarged views of cells indicated in panel B by arrows and arrowhead; sex-karyotype is indicated for each. (D) Independent patient sample also stained for X- (green) and Y- (red) chromosomes and Lamin B1 (white). Arrows indicate Y-chromosome-positive epithelial cells. Dashed lines in all panels indicate boundaries of epithelial and non-epithelial compartments.</p