624 research outputs found
Focus Stacking Images of Morphological Character States for Differentiating the Adults of \u3ci\u3eIxodes affinis\u3c/i\u3e and \u3ci\u3eIxodes scapularis\u3c/i\u3e (Acari: Ixodidae) in Areas of Sympatry
Adult females and males of Ixodes affinis and Ixodes scapularis are illustrated by focus stacking image photography, and morphological character states are described that reliably differentiate the two species. In conjunction with other environmental cues, such as the questing phenology of adults, these characteristics will enable the rapid identification of adults of either sex along the southern Coastal Plain of the United States, where these species are sympatric
Importation of Exotic Ticks and Tick-Borne Spotted Fever Group Rickettsiae into the United States by Migrating Songbirds
Birds are capable of carrying ticks and, consequently, tick-transmitted microorganisms over long distances and across geographical barriers such as oceans and deserts. Ticks are hosts for several species of spotted fever group rickettsiae (SFGR), which can be transmitted to vertebrates during blood meals. In this study, the prevalence of this group of rickettsiae was examined in ticks infesting migratory songbirds by using polymerase chain reaction (PCR). During the 2009 and 2010 spring migration season, 2064 northward-migrating passerine songbirds were examined for ticks at Johnson Bayou, Louisiana. A total of 91 ticks was removed from 35 individual songbirds for tick species identification and spotted fever group rickettsia detection. Ticks were identified as Haemaphysalis juxtakochi (n = 38, 42%), Amblyomma longirostre (n = 22, 24%), Amblyomma nodosum (n = 17, 19%), Amblyomma calcaratum (n = 11, 12%), Amblyomma maculatum (n = 2, 2%), and Haemaphysalis leporispalustris (n = 1, 1%) by comparing their 12S rDNAgene sequence to homologous sequences in GenBank. Most of the identified ticks were exotic species originating outside of the United States. The phylogenetic analysis of the 71 ompA gene sequences of the rickettsial strains detected in the ticks revealed the occurrence of 6 distinct rickettsial genotypes. Two genotypes (corresponding to a total of 28 samples) were included in the Candidatus Rickettsia amblyommii clade (less than 1% divergence), 2 of them (corresponding to a total of 14 samples) clustered with Rickettsia sp. “Argentina” with less than 0.2% sequence divergence, and 2 of them (corresponding to a total of 27 samples), although closely related to the R. parkeri–R. africae lineage (2.50–3.41% divergence), exhibited sufficient genetic divergence from its members to possibly constitute a new rickettsial genotype. Overall, there does not seem to be a specific relationship between exotic tick species, the rickettsiae they harbor, or the reservoir competence of the corresponding bird species
A pictorial key to differentiate the recently detected exotic Haemaphysalis longicornis Neumann, 1901 (Acari, Ixodidae) from native congeners in North America
Until recently, only two haemaphysaline species, Haemaphysalis chordeilis (Packard, 1869) and Haemaphysalisleporispalustris (Packard, 1869), were known to occur in the United States, and neither was consideredto be of significant medical or veterinary importance. In 2017?2018 established populations ofthe Asian longhorned tick, Haemaphysalis longicornis Neumann, 1901, were detected in the eastern US forthe first time. Haemaphysalis longicornis has the potential to be a significant threat to human and animalhealth, and the urgent need to determine the full extent of its distribution and host range requires availabilityof a straightforward and practical guide to differentiate it from native species. We created a pictorialdichotomous key to all stages of Haemaphysalis spp. known to occur in North America with scanningelectron photomicrographs of all H. longicornis life stages, including rarely seen males, to aid researchers indifferentiating these species. The largely Neotropical species Haemaphysalis juxtakochi Cooley, 1946, withestablished populations in Mexico and sporadic detections in the US on migrating birds is also included.Fil: Egizi, Andrea M.. Monmounth County Mosquito Control Division; Estados UnidosFil: Robbins, Richard G.. Smithsonian Institution; Estados UnidosFil: Beati, Lorenza. Georgia Southern University;Fil: Nava, Santiago. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Santa Fe. Estación Experimental Agropecuaria Rafaela; ArgentinaFil: Evans, Colleen R.. Georgia Southern University;Fil: Occi, James L.. Georgia Southern University;Fil: Fonseca, Dina M.. Georgia Southern University
Explorations, Vol. 2, No. 1
Cover: The painting reproduced on the cover is a 22” by 30” acrylic on paper entitled Passage-10, by James Linehan, Assistant Professor of Art at the University of Maine at Orono, where he teaches painting. ©James Linehan, 1985.
Articles include: Polyunsaturated Fats: are they killing us? by Linda J. Kling
Where are the Dreamers: aspirations of Maine\u27s rural high school students, by Robert A. Cobb, Walter G. McIntire, and Philip A. Pratt
Elsewhere in Education: a research sampler \u22Physical Education and Handicapped Children, Stephen A. Butterfield School Climate and Teacher Efficacy, Theodore Coadarci The Principal Principle, Gordon A. Donaldson, Jr. Assessing Leadership, Ronald L. Sparkes
Malnutrition in Maine, by Richard A. Cook
Hypertension: aging and intellect, by Merrill F. Elias and Michael Robbins
From Campus to Public Schools
A Ceiling on Shelter, by Peggy K. Schomaker
From the Dispatch Case: Control of Cell Growth at the Level of the Genetic Code, by R.D. Blake
In the Spring issue of EXPLORATIONS: The sure but silent force in American foreign policy in post World War II Japan—Harry F. Ker
Sitio web “Nombres de Especies de Garrapatas Duras”
Resumen
Con el fin de ofrecer a la comunidad científica las descripciones originales de especies de garrapatas duras (Acari: Ixodida: Ixodidae) se realizó un sitio web sin fin comercial y acceso irrestricto con descripciones originales de las especies (válidas e inválidas), nombres dudosos, inciertos y una selección de nomina nuda
T Cell Activation Markers and African Mitochondrial DNA Haplogroups among Non-Hispanic Black Participants in AIDS Clinical Trials Group Study 384
Introduction: Mitochondrial function influences T cell dynamics and is affected by mitochondrial DNA (mtDNA) variation. We previously reported an association between African mtDNA haplogroup L2 and less robust CD4 cell recovery on antiretroviral therapy (ART) in non-Hispanic black ACTG 384 subjects. We explored whether additional T cell parameters in this cohort differed by mtDNA haplogroup. Methods: ACTG 384 randomized ART-naïve subjects to two different nucleoside regimens with efavirenz, nelfinavir, or both. CD4 and CD8 memory and activation markers were available at baseline and week 48 on most subjects. mtDNA sequencing was performed on whole blood DNA, and haplogroups were determined. We studied non-Hispanic black subjects with HIV RNA <400 copies/mL at week 48. Analyses included Wilcoxon ranksum test and linear regression. Results: Data from 104 subjects were included. Major African mtDNA haplogroups included L1 (N = 25), L2 (N = 31), and L3 (N = 32). Baseline age, HIV RNA, and CD4 cells did not differ between L2 and non-L2 haplogroups. Compared to non-L2 haplogroups, L2 subjects had lower baseline activated CD4 cells (median 12% vs. 17%; p = 0.03) and tended toward lower activated CD8 cells (41% vs. 47%; p = 0.06). At 48 weeks of ART, L2 subjects had smaller decreases in activated CD4 cells (−4% vs. −11%; p = 0.01), and smaller CD4 cell increases (+95 vs. +178; p = 0.002). In models adjusting for baseline age, CD4 cells, HIV RNA, and naïve-to-memory CD4 cell ratio, haplogroup L2 was associated with lower baseline (p = 0.04) and 48-week change in (p = 0.01) activated CD4 cells. Conclusions: Among ART-naïve non-Hispanic blacks, mtDNA haplogroup L2 was associated with baseline and 48-week change in T cell activation, and poorer CD4 cell recovery. These data suggest mtDNA variation may influence CD4 T cell dynamics by modulating T cell activation. Further study is needed to replicate these associations and identify mechanisms
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