Browsing by Subject "Life Sciences & Biomedicine"
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Item Open Access A baseline paleoecological study for the Santa Cruz Formation (late–early Miocene) at the Atlantic coast of Patagonia, Argentina(Palaeogeography, Palaeoclimatology, Palaeoecology, 2010-06) Vizcaíno, SF; Bargo, MS; Kay, RF; Fariña, RA; Di Giacomo, M; Perry, JMG; Prevosti, FJ; Toledo, N; Cassini, GH; Fernicola, JCCoastal exposures of the Santa Cruz Formation (late-early Miocene, southern Patagonia, Argentina) between the Coyle and Gallegos rivers have been a fertile ground for recovery of Miocene vertebrates for more than 100 years. The formation contains an exceptionally rich mammal fauna, which documents a vertebrate assemblage very different from any living community, even at the ordinal level. Intensive fieldwork performed since 2003 (nearly 1200 specimens have been collected, including marsupials, xenarthrans, notoungulates, litopterns astrapotheres, rodents, and primates) document this assertion. The goal of this study is to attempt to reconstruct the trophic structure of the Santacrucian mammalian community with precise stratigraphic control. Particularly, we evaluate the depauperate carnivoran paleoguild and identify new working hypotheses about this community. A database has been built from about 390 specimens from two localities: Campo Barranca (CB) and Puesto Estancia La Costa (PLC). All species have been classified as herbivore or carnivore, their body masses estimated, and the following parameters estimated: population density, on-crop biomass, metabolic rates, and the primary and secondary productivity. According to our results, this model predicts an imbalance in both CB and PLC faunas which can be seen by comparing the secondary productivity of the ecosystem and the energetic requirements of the carnivores in it. While in CB, the difference between carnivores and herbivores is six-fold, in PLC this difference is smaller, the secondary productivity is still around three times that of the carnivore to herbivore ratio seen today. If both localities are combined, the difference rises to around four-fold in favour of secondary productivity. Finally, several working hypotheses about the Santacrucian mammalian community and the main lineages of herbivores and carnivores are offered. © 2010 Elsevier B.V. All rights reserved.Item Open Access A basic systems account of trauma memories in PTSD: is more needed?(2015-01-01) Rubin, DCItem Open Access A classification for extant ferns(Taxon, 2006-01-01) Smith, AR; Pryer, KM; Schuettpelz, E; Korall, P; Schneider, H; Wolf, PGWe present a revised classification for extant ferns, with emphasis on ordinal and familial ranks, and a synopsis of included genera. Our classification reflects recently published phylogenetic hypotheses based on both morphological and molecular data. Within our new classification, we recognize four monophyletic classes, 11 monophyletic orders, and 37 families, 32 of which are strongly supported as monophyletic. One new family, Cibotiaceae Korall, is described. The phylogenetic affinities of a few genera in the order Polypodiales are unclear and their familial placements are therefore tentative. Alphabetical lists of accepted genera (including common synonyms), families, orders, and taxa of higher rank are provided.Item Open Access A diploids-first approach to species delimitation and interpreting polyploid evolution in the fern genus astrolepis (pteridaceae)(Systematic Botany, 2010-04-01) Beck, James B; Windham, Michael D; Yatskievych, George; Pryer, Kathleen MPolyploidy presents a challenge to those wishing to delimit the species within a group and reconstruct the phylogenetic relationships among these taxa. A clear understanding of the tree-like relationships among the diploid species can provide a framework upon which to reconstruct the reticulate events that gave rise to the polyploid lineages. In this study we apply this "diploids-first" strategy to the fern genus Astrolepis (Pteridaceae). Diploids are identified using the number of spores per sporangium and spore size. Analyses of plastid and low-copy nuclear sequence data provide well-supported estimates of phylogenetic relationships, including strong evidence for two morphologically distinctive diploid lineages not recognized in recent treatments. One of these corresponds to the type of Notholaena deltoidea, a species that has not been recognized in any modern treatment of Astrolepis. This species is resurrected here as the new combination Astrolepis deltoidea . The second novel lineage is that of a diploid initially hypothesized to exist by molecular and morphological characteristics of several established Astrolepis allopolyploids. This previously missing diploid species is described here as Astrolepis obscura. © Copyright 2010 by the American Society of Plant Taxonomists.Item Open Access A molecular phylogeny of scaly tree ferns (Cyatheaceae).(American journal of botany, 2007-05) Korall, P; Conant, DS; Metzgar, JS; Schneider, H; Pryer, KMTree ferns recently were identified as the closest sister group to the hyperdiverse clade of ferns, the polypods. Although most of the 600 species of tree ferns are arborescent, the group encompasses a wide range of morphological variability, from diminutive members to the giant scaly tree ferns, Cyatheaceae. This well-known family comprises most of the tree fern diversity (∼500 species) and is widespread in tropical, subtropical, and south temperate regions of the world. Here we investigate the phylogenetic relationships of scaly tree ferns based on DNA sequence data from five plastid regions (rbcL, rbcL-accD IGS, rbcL-atpB IGS, trnG-trnR, and trnL-trnF). A basal dichotomy resolves Sphaeropteris as sister to all other taxa and scale features support these two clades: Sphaeropteris has conform scales, whereas all other taxa have marginate scales. The marginate-scaled clade consists of a basal trichotomy, with the three groups here termed (1) Cyathea (including Cnemidaria, Hymenophyllopsis, Trichipteris), (2) Alsophila sensu stricto, and (3) Gymnosphaera (previously recognized as a section within Alsophila) + A. capensis. Scaly tree ferns display a wide range of indusial structures, and although indusium shape is homoplastic it does contain useful phylogenetic information that supports some of the larger clades recognised.Item Open Access A new look at an old disease: Is Pompe disease a neuromuscular disorder with CNS involvement?(Molecular Genetics and Metabolism, 2020-02) Korlimarla, Aditi; Chen, Steven; Austin, Stephanie L; Provenzale, James M; Kishnani, Priya SItem Open Access A new non-enzymatic method for isolating human intervertebral disc cells preserves the phenotype of nucleus pulposus cells.(Cytotechnology, 2014-12) Tang, Xinyan; Richardson, William J; Fitch, Robert D; Brown, Christopher R; Isaacs, Robert E; Chen, JunCells isolated from intervertebral disc (IVD) tissues of human surgical samples are one of potential sources for the IVD cellular therapy. The purpose of this study was to develop a new non-enzymatic method, "tissue incubation", for isolating human IVD cells. The IVD tissues of annulus fibrosus (AF) and nucleus pulposus (NP) were incubated separately in tissue culture flasks with culture medium. After 7-10 days incubation, cells were able to migrate out of IVD tissues and proliferate in vitro. After 3-4 weeks culture, expanded cells were harvested by trypsinization, and the remaining tissues were transferred to a new flask for another round of incubation. The molecular phenotype of IVD cells from juvenile and adult human samples was evaluated by both flow cytometry analysis and immunocytochemical staining for the expression of protein markers of NP cells (CD24, CD54, CD239, integrin α6 and laminin α5). Flow cytometry confirmed that both AF and NP cells of all ages positively expressed CD54 and integrin α6, with higher expression levels in NP cells than in AF cells for the juvenile group sample. However, CD24 expression was only found in juvenile NP cells, and not in AF or older disc cells. Similar expression patterns for NP markers were also confirmed by immunocytochemistry. In summary, this new non-enzymatic tissue incubation method for cell isolation preserves molecular phenotypic markers of NP cells and may provide a valuable cell source for the study of NP regeneration strategies.Item Open Access A novel approach to assess livestock management effects on biodiversity of drylands(Ecological Indicators, 2015-01-01) Chillo, V; Ojeda, RA; Anand, M; Reynolds, JFIn drylands livestock grazing is the main production activity, but overgrazing due to mismanagement is a major cause of biodiversity loss. Continuous grazing around water sources generates a radial gradient of grazing intensity called the piosphere. The ecological sustainability of this system is questionable and alternative management needs to be evaluated. We apply simple indicators of species response to grazing gradients, and we propose a novel methodological approach to compare community response to grazing gradients (double reciprocal analysis). We assessed degradation gradients of biodiversity under different management strategies in semiarid rangelands of the Monte desert (Argentina) by analyzing changes in vegetation, ants and small mammal richness and diversity, and variation due to seasonality. At the species level, we determined the trend in abundance of each species along the gradient, and the potential cross-taxa surrogacy. At the community level, the new methodological consists of assessing the magnitude of biodiversity degradation along different piospheres by comparing the slopes of linear functions obtained by the double reciprocal analysis. We found that most species showed a decreasing trend along the gradient under continuous grazing; while under rotational grazing fewer species showed a decreasing trend, and a neutral trend (no change in the abundance along the gradient of grazing intensity) was the most common. We found that vegetation cannot be used as a surrogacy taxon of animal response. Moreover, weak cross-taxa surrogacy was found only for animal assemblages during the wet season. The double reciprocal analysis allowed for comparison of multi-taxa response under different seasons and management types. By its application, we found that constrains in precipitation interacted with disturbance by increasing the negative effect of grazing on vegetation, but not on animal assemblages. Continuous grazing causes biodiversity loss in all situations. Rotational grazing prevents the occurrence of vegetation degradation and maintains higher levels of animal diversity, acting as an opportunity for biodiversity conservation under current scenarios of land use extensification. Our approach highlights the importance of considering multi-taxa and intrinsic variability in the analysis, and should be of value to managers concerned with biodiversity conservation.Item Open Access A numerical analysis of chromatographic profiles in North American taxa of the fern genus Gymnocarpium(Canadian Journal of Botany, 1983-10-01) Pryer, Kathleen M; Britton, Donald M; McNeill, JohnAs part of a systematic investigation of the genus Gymnocarpium in North America, a survey of chromatographic profiles in species and hybrids of the genus was initiated. It was established through cluster analysis and ordination of the phenolic data that morphologically distinguishable taxa of Gymnocarpium can be recognized by their chromatographic profiles alone. These data provide supportive evidence for the recognition of G. robertianum and G. jessoense ssp. parvulum as distinct taxa and for the hybrid status of G. × intermedium. They also suggest that, as currently circumscribed, G. jessoense ssp. jessoense is a heterogeneous taxon.Item Open Access A plastid phylogeny of the cosmopolitan fern family cystopteridaceae (Polypodiopsida)(Systematic Botany, 2013-06-01) Rothfels, CJ; Windham, MD; Pryer, KMAmong the novel results of recent molecular phylogenetic analyses are the unexpectedly close evolutionary relationships of the genera Acystopteris, Cystopteris, and Gymnocarpium, and the phylogenetic isolation of these genera from Woodsia. As a consequence, these three genera have been removed from Woodsiaceae and placed into their own family, the Cystopteridaceae. Despite the ubiquity of this family in rocky habitats across the northern hemisphere, and its cosmopolitan distribution (occurring on every continent except Antarctica), sampling of the Cystopteridaceae in phylogenetic studies to date has been sparse. Here we assemble a three-locus plastid dataset (matK, rbcL, trnG-R) that includes most recognized species in the family and multiple accessions of widespread taxa from across their geographic ranges. All three sampled genera are robustly supported as monophyletic, Cystopteris is strongly supported as sister to Acystopteris, and those two genera together are sister to Gymnocarpium. The Gymnocarpium phylogeny is deeply divided into three major clades, which we label the disjunctum clade, the robertianum clade, and core Gymnocarpium. The Cystopteris phylogeny, similarly, features four deeply diverged clades: C. montana, the sudetica clade, the bulbifera clade, and the fragilis complex. Acystopteris includes only three species, each of which is supported as monophyletic, with A. taiwaniana sister to the japonica/tenuisecta clade. Our results yield the first species-level phylogeny of the Cystopteridaceae and the first molecular phylogenetic evidence for species boundaries. These data provide an essential foundation for further investigations of complex patterns of geographic diversification, speciation, and reticulation in this family. © Copyright 2013 by the American Society of Plant Taxonomists.Item Open Access A Review of Current Practice in Transfusion Therapy(AMERICAN JOURNAL OF NURSING, 2018-05-01) Carman, Margaret; Uhlenbrock, Jennifer Schieferle; McClintock, Sara MarieItem Open Access A revised family-level classification for eupolypod II ferns (Polypodiidae: Polypodiales)(Taxon, 2012-01-01) Rothfels, CJ; Sundue, MA; Kuo, L; Larsson, A; Kato, M; Schuettpelz, E; Pryer, KMWe present a family-level classification for the eupolypod II clade of leptosporangiate ferns, one of the two major lineages within the Eupolypods, and one of the few parts of the fern tree of life where family-level relationships were not well understood at the time of publication of the 2006 fern classification by Smith & al. Comprising over 2500 species, the composition and particularly the relationships among the major clades of this group have historically been contentious and defied phylogenetic resolution until very recently. Our classification reflects the most current available data, largely derived from published molecular phylogenetic studies. In comparison with the five-family (Aspleniaceae, Blechnaceae, Onocleaceae, Thelypteridaceae, Woodsiaceae) treatment of Smith & al., we recognize 10 families within the eupolypod II clade. Of these, Aspleniaceae, Thelypteridaceae, Blechnaceae, and Onocleaceae have the same composition as treated by Smith & al. Woodsiaceae, which Smith & al. acknowledged as possibly non-monophyletic in their treatment, is circumscribed here to include only Woodsia and its segregates; the other "woodsioid" taxa are divided among Athyriaceae, Cystopteridaceae, Diplaziopsidaceae, Rhachidosoraceae, and Hemidictyaceae. We provide circumscriptions for each family, which summarize their morphological, geographical, and ecological characters, as well as a dichotomous key to the eupolypod II families. Three of these families- Diplaziopsidaceae, Hemidictyaceae, and Rhachidosoraceae-were described in the past year based on molecular phylogenetic analyses; we provide here their first morphological treatment.Item Open Access A revised generic classification of vittarioid ferns (Pteridaceae) based on molecular, micromorphological, and geographic data(Taxon, 2016-08-01) Schuettpelz, E; Chen, C; Kessler, M; Pinson, JB; Johnson, G; Davila, A; Cochran, AT; Huiet, L; Pryer, KM© International Association for Plant Taxonomy (IAPT) 2016. Vittarioid ferns compose a well-supported clade of 100-130 species of highly simplified epiphytes in the family Pteridaceae. Generic circumscriptions within the vittarioid clade were among the first in ferns to be evaluated and revised based on molecular phylogenetic data. Initial analyses of rbcL sequences revealed strong geographic structure and demonstrated that the two largest vittarioid genera, as then defined, each had phylogenetically distinct American and Old World components. The results of subsequent studies that included as many as 36 individuals of 33 species, but still relied on a single gene, were generally consistent with the early findings. Here, we build upon the previous datasets, incorporating many more samples (138 individuals representing 72 species) and additional plastid markers (atpA, chlN, rbcL, rpoA). Analysis of our larger dataset serves to better characterize known lineages, reveals new lineages, and ultimately uncovers an underlying geographic signal that is even stronger than was previously appreciated. In our revised generic classification, we recognize a total of eleven vittarioid genera. Each genus, including the new genus Antrophyopsis (Benedict) Schuettp., stat. nov., is readily diagnosable based on morphology, with micromorphological characters related to soral paraphyses and spores complementing more obvious features such as venation and the distribution of sporangia. A key to the currently recognized vittarioid genera, brief generic descriptions, and five new species combinations are provided.Item Open Access A Structural Event Approach to the Analysis of Group Composition(Social Networks, 2002) Ruef, MSince Simmel's early work on forms of association, the processes guiding group composition have commanded considerable attention in structural sociology, but have not led to a general methodology for examining compositional properties. By introducing a structural event approach, this study offers a new technique that is not restricted to analysis of dyads or triads nor post hoc analysis of those structural arrangements that are observed in a given sample. The approach is illustrated using data on 745 organizational founding teams. Structural event analysis separates choice behavior guiding team composition (with respect to ascribed and achieved characteristics of members) from structurally-induced behavior based on contact opportunities. Results suggest that the strong impact of ascriptive homophily may be tempered when functional considerations of group composition are addressed. However, many of the other arrangements that ostensibly pass as 'functional' are in fact induced by opportunity structures. © 2002 Elsevier Science B.V. All rights reserved.Item Open Access A synopsis of the genus Sanicula (Apiaceae) in eastern Canada(Canadian Journal of Botany, 1989-01-01) Pryer, KM; Phillippe, LRFour species and 2 varieties of these native woodland umbellifers are recognized. A key to the taxa, comparative descriptions of diagnostic characters, and notes on the taxonomy, distribution, habitat, and rare status are provided. Eastern Canadian dot maps and North American range maps are included for each taxon. -from AuthorsItem Open Access A worldwide phylogeny of Adiantum (Pteridaceae) reveals remarkable convergent evolution in leaf blade architecture(Taxon, 2018-06-01) Huiet, L; Li, F; Kao, T; Prado, J; Smith, AR; Schuettpelz, E; Pryeri, KM© International Association for Plant Taxonomy (IAPT) 2018, All rights reserved. Adiantum is among the most distinctive and easily recognized leptosporangiate fern genera. Despite encompassing an astonishing range of leaf complexity, all species of Adiantum share a unique character state not observed in other ferns: sporangia borne directly on the reflexed leaf margin or “false indusium” (pseudoindusium). The over 200 species of Adiantum span six continents and are nearly all terrestrial. Here, we present one of the most comprehensive phylogenies for any large (200+ spp.) monophyletic, subcosmopolitan genus of ferns to date. We build upon previous datasets, providing new data from four plastid markers (rbcL, atpA, rpoA, chlN) for 146 taxa. All sampled taxa can be unequivocally assigned to one of nine robustly supported clades. Although some of these unite to form larger, well-supported lineages, the backbone of our phylogeny has several short branches and generally weak support, making it difficult to accurately assess deep relationships. Our maximum likelihood-based ancestral character state reconstructions of leaf blade architecture reveal remarkable convergent evolution across multiple clades for nearly all leaf forms. A single unique synapomorphy—leaves once-pinnate, usually with prolonged rooting tips—defines the philippense clade. Although a rare occurrence in Adiantum, simple leaves occur in three distinct clades (davidii, philippense, peruvianum). Most taxa have leaves that are more than once-pinnate, and only a few of these (in the formosum and pedatum clades) exhibit the distinct pseudopedate form. Distributional ranges for each of the terminal taxa show that most species (75%) are restricted to only one of six major biogeographical regions. Forty-eight of our sampled species (nearly one-third) are endemic to South America.Item Open Access Adapting culturally appropriate mental health screening tools for use among conflict-affected and other vulnerable adolescents in Nigeria(Global Mental Health, 2019) Kaiser, BN; Ticao, C; Anoje, C; Minto, J; Boglosa, J; Kohrt, BABackgroundThe Boko Haram insurgency has brought turmoil and instability to Nigeria, generating a large number of internally displaced people and adding to the country's 17.5 million orphans and vulnerable children. Recently, steps have been taken to improve the mental healthcare infrastructure in Nigeria, including revamping national policies and initiating training of primary care providers in mental healthcare. In order for these efforts to succeed, they require means for community-based detection and linkage to care. A major gap preventing such efforts is the shortage of culturally appropriate, valid screening tools for identifying emotional and behavioral disorders among adolescents. In particular, studies have not conducted simultaneous validation of screening tools in multiple languages, to support screening and detection efforts in linguistically diverse populations. We aim to culturally adapt screening tools for emotional and behavioral disorders for use among adolescents in Nigeria, in order to facilitate future validation studies.MethodsWe used a rigorous mixed-method process to culturally adapt the Depression Self Rating Scale, Child PTSD Symptom Scale, and Disruptive Behavior Disorders Rating Scale. We employed expert translations, focus group discussions (N = 24), and piloting with cognitive interviewing (N = 24) to achieve semantic, content, technical, and criterion equivalence of screening tool items.ResultsWe identified and adapted items that were conceptually difficult for adolescents to understand, conceptually non-equivalent across languages, considered unacceptable to discuss, or stigmatizing. Findings regarding problematic items largely align with existing literature regarding cross-cultural adaptation.ConclusionsCulturally adapting screening tools represents a vital first step toward improving community case detection.Item Open Access Adaptive wear-based changes in dental topography associated with atelid (Mammalia: Primates) diets(Biological Journal of the Linnean Society, 2018-06-28) Pampush, JD; Spradley, JP; Morse, PE; Griffith, D; Gladman, JT; Gonzales, LA; Kay, RFItem Open Access Advances in Color Science: From Retina to Behavior (vol 30, pg 14955, 2010)(JOURNAL OF NEUROSCIENCE, 2010-12-08) Conway, Bevil R; Chatterjee, Soumya; Field, Greg D; Horwitz, Gregory D; Johnson, Elizabeth N; Koida, Kowa; Mancuso, KatherineItem Open Access Age-Related Adverse Inflammatory and Metabolic Changes Begin Early in Adulthood.(The journals of gerontology. Series A, Biological sciences and medical sciences, 2018-05-22) Parker, Daniel; Sloane, Richard; Pieper, Carl F; Hall, Katherine S; Kraus, Virginia B; Kraus, William E; Huebner, Janet L; Ilkayeva, Olga R; Bain, James R; Newby, L Kristin; Cohen, Harvey Jay; Morey, Miriam CAging is characterized by deleterious immune and metabolic changes, but the onset of these changes is unknown. We measured immune and metabolic biomarkers in adults beginning at age 30. To our knowledge, this is the first study to evaluate these biomarkers in adults aged 30 to over 80. Biomarkers were quantified in 961 adults. Tumor necrosis factor alpha (TNF-α), tumor necrosis factor receptor I (TNFR-I), tumor necrosis factor receptor II (TNFR-II), interleukin (IL)-2, IL-6, VCAM-I, D-Dimer, G-CSF, regulated on activation, normal T cell expressed and secreted (RANTES), matrix metalloproteinase-3 (MMP-3), adiponectin, and paraoxonase activity were measured by ELISA. Acylcarnitines and amino acids (AAs) were measured by mass spectrometry and reduced to a single factor using principal components analysis (PCA). Glycine was analyzed separately. The relationship between age and biomarkers was analyzed by linear regression with sex, race, and body mass index (BMI) as covariates. Age was positively correlated with TNF-α, TNFR-I, TNFR-II, IL-6, IL-2, VCAM-1, D-Dimer, MMP-3, adiponectin, acylcarnitines, and AAs. Age was negative correlated with G-CSF, RANTES, and paraoxonase activity. BMI was significant for all biomarkers except IL-2, VCAM-1, RANTES, paraoxonase activity, and the AA factor. Excluding MMP-3, greater BMI was associated with potentially adverse changes in biomarker concentrations. Age-related changes in immune and metabolic biomarkers, known to be associated with poor outcomes in older adults, begin as early as the thirties.