bluuebunny/crossref_metadata_2025 huggingface dataset:
The Biology of Emergency Medicine: What Have 30 Years Meant for Rosen’s Original Concepts?
Authors: Zink Brian J.
Published: February 2011

ACADEMIC EMERGENCY MEDICINE 2011; 18:301–304 © 2011 by the Society for Academic Emergency Medicine

In 1979 Peter Rosen, MD, a leading academic figure in the developing field of emergency medicine (EM), wrote an article, “The Biology of Emergency Medicine,” in response to criticism from other specialties and medical leaders that there was no unique biology of EM that would qualify it as a legitimate medical specialty. This essay received much attention at the time and served as rallying cry for emergency physicians (EPs) who were trying to find their places in the house of medicine and especially in medical schools and academic teaching hospitals. Thirty years later, the opposition that prompted many of Rosen’s strongly worded impressions and observations on the biology of EM, clinical emergency department (ED) practice, education, and research has largely faded. Many of Rosen’s predictions on the eventual success of EM have come true. However, core issues that existed then continue to present challenges for academic EM and clinical emergency practice.

ACADEMIC EMERGENCY MEDICINE 2011; 18:1–4 © 2011 by the Society for Academic Emergency Medicine
Functional analysis of microRNAs in human hepatocellular cancer stem cells
Authors: Meng Fanyin , Glaser Shannon S. , Francis Heather , DeMorrow Sharon , Han Yuyan , Passarini Jenna D. , Stokes Allison , Cleary John P. , Liu Xiuping , Venter Julie , Kumar Preetham , Priester Sally , Hubble Levi , Staloch Dustin , Sharma Jay , Liu Chang‐Gong , Alpini Gianfranco
Published: February 2011

MicroRNAs are endogenous small non‐coding RNAs that regulate gene expression and cancer development. A rare population of hepatocellular cancer stem cells (HSCs) holds the extensive proliferative and self‐renewal potential necessary to form a liver tumour. We postulated that specific transcriptional factors might regulate the expression of microRNAs and subsequently modulate the expression of gene products involved in phenotypic characteristics of HSCs. We evaluated the expression of microRNA in human HSCs by microarray profiling, and defined the target genes and functional effects of two groups of microRNA regulated by IL‐6 and transcriptional factor Twist. A subset of highly chemoresistant and invasive HSCs was screened with aberrant expressions of cytokine IL‐6 and Twist. We demonstrated that conserved let‐7 and miR‐181 family members were up‐regulated in HSCs by global microarray‐based microRNA profiling followed by validation with real‐time polymerase chain reaction. Importantly, inhibition of let‐7 increases the chemosensitivity of HSCs to sorafenib and doxorubicin whereas silencing of miR‐181 led to a reduction in HSCs motility and invasion. Knocking down IL‐6 and Twist in HSCs significantly reduced let‐7 and miR‐181 expression and subsequently inhibited chemoresistance and cell invasion. We showed that let‐7 directly targets SOCS‐1 and caspase‐3, whereas miR‐181 directly targets RASSF1A, TIMP3 as well as nemo‐like kinase (NLK). In conclusion, alterations of IL‐6‐ and Twist‐regulated microRNA expression in HSCs play a part in tumour spreading and responsiveness to chemotherapy. Our results define a novel regulatory mechanism of let‐7/miR‐181s suggesting that let‐7 and miR‐181 may be molecular targets for eradication of hepatocellular malignancies.
Prostate cancer‐derived angiogenin stimulates the invasion of prostate fibroblasts
Authors: Jones Michelle L. , Ewing Charles M. , Isaacsa William B. , Getzenberg Robert H.
Published: February 2011

Prostate fibroblasts promote prostate cancer progression by secreting factors that enhance tumour growth and induce the migration and invasion of prostate cancer cells. Considering the role of fibroblasts in cancer progression, we hypothesized that prostate cancer cells recruit these cells to their vicinity, where they are most directly available to influence cancer cell behaviour. To test this hypothesis, we performed modified Boyden chamber assays assessing the migration and collagen I invasion of normal primary prostate fibroblasts (PrSCs) and prostate cancer‐associated fibroblasts (PCAFs) in response to media conditioned by the metastatic prostate cancer cell lines PC‐3, LNCaP and DU145. During 4‐hr incubations, PrSCs and PCAFs migrated and invaded in response to the conditioned media. To identify candidate proteins in the conditioned media that produced these effects, we performed cytokine antibody arrays and detected angiogenin in all three media. Angiogenin‐blocked PC‐3‐conditioned medium, obtained using an anti‐angiogenin polyclonal antibody or angiogenin siRNA, significantly reduced PC‐3‐induced PrSC and PCAF collagen I invasion. Furthermore, angiogenin alone at 1, 2 and 5 ng/ml significantly stimulated PCAF collagen I invasion. These results suggest that PC‐3‐derived angiogenin stimulates the invasion of normal prostate fibroblasts and PCAFs and is sufficient for invasion of the latter. Because prostate fibroblasts play key roles in prostate cancer progression, targeting their invasion using an anti‐angiogenin‐based therapy may be a strategy for preventing or treating advanced prostate cancer.
Multifaceted role of nitric oxide in an in vitro mouse neuronal injury model: transcriptomic profiling defines the temporal recruitment of death signalling cascades
Authors: Peng Zhao Feng , Chen Minghui Jessica , Manikandan Jayapal , Melendez Alirio J. , Shui Guanghou , Russo‐Marie Françoise , Whiteman Matthew , Beart Philip M. , Moore Philip K. , Cheung Nam Sang
Published: February 2011

Nitric oxide is implicated in the pathogenesis of various neuropathologies characterized by oxidative stress. Although nitric oxide has been reported to be involved in the exacerbation of oxidative stress observed in several neuropathologies, existent data fail to provide a holistic description of how nitrergic pathobiology elicits neuronal injury. Here we provide a comprehensive description of mechanisms contributing to nitric oxide induced neuronal injury by global transcriptomic profiling. Microarray analyses were undertaken on RNA from murine primary cortical neurons treated with the nitric oxide generator DETA‐NONOate (NOC‐18, 0.5 mM) for 8–24 hrs. Biological pathway analysis focused upon 3672 gene probes which demonstrated at least a ±1.5‐fold expression in a minimum of one out of three time‐points and passed statistical analysis (one‐way anova, P < 0.05). Numerous enriched processes potentially determining nitric oxide mediated neuronal injury were identified from the transcriptomic profile: cell death, developmental growth and survival, cell cycle, calcium ion homeostasis, endoplasmic reticulum stress, oxidative stress, mitochondrial homeostasis, ubiquitin‐mediated proteolysis, and GSH and nitric oxide metabolism. Our detailed time‐course study of nitric oxide induced neuronal injury allowed us to provide the first time a holistic description of the temporal sequence of cellular events contributing to nitrergic injury. These data form a foundation for the development of screening platforms and define targets for intervention in nitric oxide neuropathologies where nitric oxide mediated injury is causative.
Accuracy of frozen section diagnosis: a retrospective analysis of 4785 cases
Authors: WINTHER CHARLOTTE , GRÆM NIELS
Published: February 2011

Winther C, Græm N. Accuracy of frozen section diagnosis: a retrospective analysis of 4785 cases. APMIS 2011; 119: 259–62.

During a 1‐year period 4785 intraoperative consultations were performed. The pathology reports were retrospectively reviewed to determine the accuracy of frozen section diagnosis in various tissue types. Skin for evaluation of section margins and axillary sentinel lymph nodes for evaluation of metastatic disease were most frequently sent for frozen section diagnosis. The number of discordant cases were 182, 178 were false negative and four were false positive. When frozen section diagnoses were compared with permanent section diagnoses, the overall diagnostic concordance was 95.1%. The number of deferred specimens was 57. The accuracy of frozen section diagnosis varied between tissue types, and axillary sentinel lymph nodes accounted for the greatest number of discordances. In conclusion, the frozen section diagnosis is a reliable method with varying concordance and deferral rates between tissue types. We suggest regular monitoring of the performance in frozen section diagnosis.
Mucoid Pseudomonas aeruginosa isolates maintain the biofilm formation capacity and the gene expression profiles during the chronic lung infection of CF patients
Authors: LEE BAOLERI , SCHJERLING CHARLOTTE K. , KIRKBY NIKOLAI , HOFFMANN NADINE , BORUP REHANNAH , MOLIN SØREN , HØIBY NIELS , CIOFU OANA
Published: February 2011

Lee B, Schjerling CK, Kirkby N, Hoffmann N, Borup R, Molin S, Høiby N, Ciofu O. Mucoid Pseudomonas aeruginosa isolates maintain the biofilm formation capacity and the gene expression profiles during the chronic lung infection of CF patients. APMIS 2011; 119: 263–74.

Phenotypic and genotypic diversifications of Pseudomonas aeruginosa in the airways of patients with cystic fibrosis (CF) promote long‐term survival of bacteria during chronic lung infection. Twelve clonally related, sequential mucoid and non‐mucoid paired P. aeruginosa isolates obtained from three Danish CF patients were investigated. The in vitro biofilm formation capacity was studied under static and flow through conditions and the global gene expression profiles were investigated by Affymetrix GeneChip. Regulatory genes of alginate production and quorum sensing (QS) system were sequenced and measurements of the alginate production and the detection of the QS signal molecules were performed. Comparisons of mucoid and non‐mucoid isolates from early and late stages of the infection showed that the mucoid phenotype maintained over a decade the capacity to form in vitro biofilm and showed an unaltered transcriptional profile, whereas substantial alterations in the transcriptional profiles and loss of the capacity to form in vitro biofilms were observed in corresponding isolates of the non‐mucoid phenotype. The conserved gene expression pattern in the mucoid isolates vs the diversity of changes in non‐mucoid isolates observed in this particular P. aeruginosa clone reflects different adaptation strategies used by these two phenotypes in the different niches of the CF lung environment.
Sources of variation in the nesting success of understory tropical birds
Authors: Brawn Jeffrey D. , Angehr George , Davros Nicole , Robinson W. Douglas , Styrsky Jennifer N. , Tarwater Corey E.
Published: February 2011

Survival of offspring is a key fitness component and, for birds, the threat of predation on nests is especially influential. Data on rates of nest success from tropical regions are comparatively few, conservation‐relevant, and essential for assessing the validity of models comparing the life histories and behavior or birds across latitudinal gradients. We monitored over 2 000 nests in the lowland forests of central Panama and, using the logistic exposure to model the fate of nests, explored the importance of variation in rate of nest success according to type of nest, height of nests, among years, in early versus late nests, and at different stages of the nest cycle. Analyses of over 1 400 nests for 18 species revealed considerable variation among species in the daily survival rate of nests (range among 18 species=0.91 to 0.98), but nest type and stage of the nesting cycle were generally influential on the probability of nest success. Cavity or enclosed nesters experienced greater nest success than open cup nesters and rates of nest loss were generally greatest in the nestling stage. We found limited evidence that height of nests affected probability of success, but no indication that timing of nesting effort was influential. Despite the occurrence of a severe ENSO event during our sampling, annual variation in nest success was not consistent among species. Interspecific variation in the rates and patterns of nest predation in our study, coupled with reports of high rates of nest loss at temperate latitudes, lead us to question long standing assumptions about latitudinal trends in rates of nest loss. We urge further work to understand the implications of nest predation on the evolutionary ecology of tropical birds.
Informative content of melanin‐based plumage colour in adult Eurasian kestrels
Authors: Parejo Deseada , Silva Nadia , Danchin Étienne , Avilés Jesús M.
Published: February 2011

Covariation between melanin‐based colorations and other phenotypic attributes has been rarely measured simultaneously in males and females. Such covariations and mechanisms mediating them have crucial importance determining the signalling function of these coloured ornaments in the two sexes. We examined the role of four melanin‐based coloured plumage patches as indicators of quality in both males and females of the sexually dimorphic and dichromatic Eurasian kestrel Falco tinnunculus. Previous kestrel studies have focused on the size of melanin plumage patches in either males or females as indicators of individual quality. Here, we used spectrophotometric measurements of three plumage patches and the size of another plumage patch to investigate the information content of multiple plumage colour traits in male and female kestrels. We found that females with bright plumage in the head and with high UV chroma in black parts of the rump showed good body condition and innate immunity. In addition, laying date was significantly explained by the intensity of the brown in the head of females. Meanwhile, in males we only found that individuals with greyer rumps showed better innate immunity. Altogether, our results indicate that, irrespective of the mechanism promoting covariation between coloration and individual quality, melanin‐based coloration can inform on individual quality in adult kestrels.
Seasonal changes in moult, body mass and reproductive condition in siskins Carduelis spinus exposed to daylength regimes simulating different latitudes
Authors: Newton Ian , Dawson Alistair
Published: February 2011

Birds use change in daylength during the year to time events during their annual cycles. Individual Eurasian siskins Carduelis spinus can breed and winter in widely separated areas in different years. Birds at different latitudes will experience different changes in photoperiod. So how does latitude affect photoperiodic control? Our aim in this study was to find whether Siskins caught from the wild in Britain and exposed to different photoperiodic regimes, typical of widely separated latitudes, would differ in the subsequent timing and duration of their moults and associated processes. Siskins were caught in late February and early March, and initially kept outside on natural photoperiods. From the spring equinox (21 March), they were divided into three groups kept under photoperiodic regimes that simulated latitudes 40°, 55° and 70°N respectively. All three groups showed highly significant subsequent changes in body mass, fat scores and cloacal protuberance size. Moult of the primary feathers started during June – August (mean 9 July), and lasted 61–99 days (mean 75 days). Birds that started to moult late in the season had shorter moult durations. All individuals showed lower mass and fat levels during moult than before or after moult. Crucially, there were no significant differences in the timing of these events between the three photoperiodic groups. Apparently these birds did not use prevailing absolute photoperiod or the prevailing rate of change in photoperiod to time moult‐related seasonal events, but used instead some other feature of the annual photoperiod cycle or some form of interval timer linked to photoperiod.
Piecing together the global population puzzle of wandering albatrosses: genetic analysis of the Amsterdam albatross Diomedea amsterdamensis
Authors: Rains Derek , Weimerskirch Henri , Burg Theresa M
Published: February 2011

Wandering albatrosses have been subjected to numerous taxonomic revisions due to discoveries of new species, analyses of morphological data and, more recently, the inclusion of genetic data. The small population of albatrosses (170 individuals including 26 pairs breeding annually) on Amsterdam Island in the Indian Ocean, Diomedea amsterdamensis, has been given species status based on plumage and morphometrics, but genetic data published to date provide weak support and its specific status remains controversial for some authors. We used mitochondrial control region sequence data to elucidate the relationship of the Amsterdam albatross within the wandering albatross complex (Diomedea amsterdamensis, D. antipodensis, D. dabbenena and D. exulans). Three novel haplotypes were present in 35 individuals from Amsterdam Island, and were highly divergent (3.6–7.3%) from haplotypes found in the other three members of the wandering albatross complex. Low levels of genetic variation in Amsterdam albatross likely resulted, at least in part, from a population bottleneck. Geographic isolation in the wandering albatross complex is maintained by high natal philopatry. As Amsterdam Island is the only breeding ground for this critically endangered species, we strongly urge conservation efforts in the area, especially in relation to long line fisheries and other threats such as disease and introduced predators, and it be listed as a distinct species.
Dyshidrotic mycosis fungoides
Authors: Diehl Joseph , Sarantopoulos G. Peter , Chiu Melvin W.
Published: February 2011

Mycosis fungoides (MF) represents the most common type of cutaneous T‐cell lymphoma (CTCL). CTCL often progresses through patch, plaque and tumor stages but can also manifest with varied clinical presentations. MF rarely presents in vesiculobullous fashion, in which vesicles or bullae develop in pre‐existing plaques or on the trunk or proximal extremities. We report a patient who presented with a vesiculobullous eruption on the palms and soles, resembling dyshidrotic dermatitis, which we believe represents dyshidrotic MF.

Diehl J, Sarantopoulos GP, Chiu MW. Dyshidrotic mycosis fungoides.
Cystic fibrosis transmembrane conductance regulator is helpful in the distinction of extra‐mammary Paget's disease from squamous cell carcinoma in situ (Bowen's disease)
Authors: Bains Rick , Gleason Briana C. , Thomas Antoinette B. , Victor Thomas A. , Cibull Thomas L.
Published: February 2011

Cystic fibrosis transmembrane conductance regulator (CFTR) represents a cAMP‐dependent channel found in normal apocrine glands. The classification and histogenesis of extra‐mammary Paget's disease (EMPD) remains controversial, but it is generally accepted that primary EMPD exhibits apocrine differentiation. Therefore, we examined the utility of CFTR in the differential diagnosis of EMPD and squamous cell carcinoma in situ (SCCIS). Twenty‐five cases of SCCIS and 14 cases of EMPD were evaluated for immunohistochemical expression of CFTR. Expression was scored as 0 (<5% of cells positive), 1+ (5–75% of cells positive) or 2+ (>75% cells positive). Twenty‐three of 25 cases of SCCIS showed no reactivity for CFTR, and the remaining 2 cases showed 1+ staining. Thirteen of 14 cases of EMPD showed 2+ staining, while 1 case showed 1+ staining. We recognize that the pathological appearance along with clinical history and site of occurrence are sufficient to distinguish EMPD and SCCIS in most instances. However, distinction between the two can become more challenging when the location and histopathology are not characteristic. We conclude that when an immunohistochemical panel is diagnostically necessary, the expression of CFTR favors a diagnosis of EMPD over SCCIS.

Bains R, Gleason BC, Thomas AB, Victor TA, Cibull TL. Cystic fibrosis transmembrane conductance regulator is helpful in the distinction of extra‐mammary Paget's disease from squamous cell carcinoma in situ (Bowen's disease).
Follicular stem cell marker PHLDA1 (TDAG51) is superior to cytokeratin‐20 in differentiating between trichoepithelioma and basal cell carcinoma in small biopsy specimens
Authors: Sellheyer Klaus , Nelson Paula
Published: February 2011

Background: Biopsies submitted to dermatopathologists are becoming increasingly smaller in size and thus the available diagnostic material is reduced. The distinction between trichoepithelioma and basal cell carcinoma remains challenging, particularly if tissue is limited. Merkel cells, which can be highlighted by means of cytokeratin‐20 (CK20) immunostaining, are used as a surrogate marker for the diagnosis of trichoepithelioma, as Merkel cells commonly colonize trichoepithelioma but are generally lacking in basal cell carcinomas. In the current study, we examined the expression of a recently characterized follicular stem cell marker, PHLDA1 (pleckstrin homology‐like domain, family A, member 1), also known as TDAG51 (T‐cell death‐associated gene 51).

Methods: Using standard immunohistochemical techniques, we examined 19 trichoepitheliomas and 11 basal cell carcinomas for the expression of PHLDA1 and compared it with CK20 expression.

Results: All 19 trichoepitheliomas were immunoreactive for PHLDA1 and all 11 basal cell carcinomas lacked PHLDA1 expression. Two of eleven basal cell carcinomas harbored CK20‐positive Merkel cells. Three trichoepitheliomas lacked secondary CK20‐positive cells.

Conclusions: Our results suggest that PHLDA1 represents a practical and easily used tool that can be applied to the differentiation of trichoepithelioma and basal cell carcinoma in small biopsy specimens. Rather than searching for CK20‐positive Merkel cells, assessing PHLDA1 expression allows the differential diagnosis between trichoepithelioma and basal cell carcinoma to be solved at scanning magnification.

Sellheyer K, Nelson P. Follicular stem cell marker PHLDA1 (TDAG51) is superior to cytokeratin‐20 in differentiating between trichoepithelioma and basal cell carcinoma in small biopsy specimens.
Identification of the STAT5B‐RARα fusion transcript in an acute promyelocytic leukemia patient without FLT3, NPM1, c‐Kit and C/EBPα mutation
Authors: Qiao Chun , Zhang Su‐Jiang , Chen Li‐Juan , Miao Kou‐Rong , Zhang Jian‐Fu , Wu Yu‐Jie , Qiu Hai‐Rong , Li Jian‐Yong
Published: February 2011

T(15;17) is the most common chromosomal aberration in patients with acute promyelocytic leukemia (APL), leading to the formation of PML‐RARα fusion gene. In a small subset of patients with APL, the RARα gene is fused with different partners. Here, we report a rare APL case with STAT5B‐RARα fusion transcript. Cytomorphologic and immunophenotypic analyses showed typical features of APL. However, cytogenetic analysis showed normal karyotype, and interphase fluorescence in situ hybridization (FISH) showed PML‐RARα negative. Quantitative RT‐PCR also showed PML‐RARα negative but STAT5B‐RARα positive and sequencing analysis confirmed the result. Molecular markers including FLT3, NPM1, c‐Kit and C/EBPα mutation were all negative. To our knowledge, this is the first APL patient with STAT5B‐RARα in Chinese population and the fifth patient around the world according to published paper.
Capital energy drives production of multiple clutches whereas income energy fuels growth in female collared lizards Crotaphytus collaris
Authors: Telemeco Rorry S. , Baird Troy A.
Published: February 2011

Animals invest energy in reproduction that is obtained at two distinct times relative to the reproductive cycle. Energy obtained during egg production is referred to as income energy whereas stored energy acquired prior to reproduction is capital energy. Similar to most ectotherms, squamate reptiles are generally hypothesized to be capital breeders. Nearly all squamates in which income/capital energy investment has been examined thus far produce only one clutch per reproductive season. Although it is likely that squamates producing multiple seasonal clutches fuel first clutches with capital energy, either capital or income energy may be used to produce later clutches. We first monitored female eastern collared lizards over 14 reproductive seasons to confirm that the number of clutches females produce seasonally is a plastic response to variable environmental parameters, and to examine the effects of female body condition at the beginning of the reproductive season on clutch production. Clutch production varied annually and both the size and number of clutches were positively correlated with body condition. We then tested the competing predictions of the income and capital hypotheses experimentally by supplementing the diets of female collared lizards in situ for one season. Diet‐supplementation had no effect on the number of clutches produced but increased growth rates of gravid females. We further tested the competing predictions of these two hypotheses by examining variation in maternal energy investment per clutch using preserved specimens collected near our primary field site. Clutch size was highly correlated with female body size. Together, our results suggest that variation in reproductive output by female collared lizards is linked to stored capital energy rather than income energy, similar to most ectotherms.
Annual variation of community biomass is lower in more diverse stream fish communities
Authors: Franssen Nathan R. , Tobler Michael , Gido Keith B.
Published: February 2011

Anthropogenic influences have disproportionally affected freshwater ecosystems, and a loss of biodiversity is forecasted to greatly reduce ecosystem function and services. Loss of species may destabilize communities by limiting the stabilizing forces of compensatory dynamics and/or statistical averaging, both of which are effects that can buffer variation in aggregate community properties. Currently, support for positive diversity‐stability relationships stems from experiments with simple communities at small spatial and temporal scales, and application to natural communities is limited. Using a long‐term dataset of 35 stream fish communities matched with hydrologic data, we show that community stability (annual variation of standing biomass of fishes) was less variable in more species‐rich communities and was not associated with stream hydrology. Only the statistical averaging model of community stability was consistent with observed patterns of lower biomass variation in more species‐rich communities. Our findings suggest anthropogenically induced extirpation of vertebrate consumers may lower community biomass stability in complex ecosystems.
Exploring patterns and mechanisms of interspecific and intraspecific variation in body elemental composition of desert consumers
Authors: González Angélica L. , Fariña José Miguel , Kay Adam D. , Pinto Raquel , Marquet Pablo A.
Published: February 2011

Key processes such as trophic interactions and nutrient cycling are often influenced by the element content of organisms. Previous analyses have led to some preliminary understanding of the relative importance of evolutionary and ecological factors determining animal stoichiometry. However, to date, the patterns and underlying mechanisms of consumer stoichiometry at interspecific and intraspecific levels within natural ecosystems remain poorly investigated. Here, we examine the association between phylogeny, trophic level, body size, and ontogeny and the elemental composition of 22 arthropod as well as two lizard species from the coastal zone of the Atacama Desert in Chile. We found that, in general, whole‐body P content was more variable than body N content both among and within species. Body P content showed a significant phylogenetic signal; however, phylogeny explained only 4% of the variation in body P content across arthropod species. We also found a significant association between trophic level and the element content of arthropods, with carnivores having 15% greater N and 70% greater P contents than herbivores. Elemental scaling relationships across species were only significant for body P content, and even the P content scaling relationship was not significant after controlling for phylogeny. P content did decrease significantly with body size within most arthropod species, which may reflect the size dependence of RNA content in invertebrates. In contrast, larger lizards had higher P contents and lower N:P ratios than smaller lizards, which may be explained by size‐associated differences in bone and scale investments. Our results suggests that structural differences in material allocation, trophic level and phylogeny can all contribute to variation in the stoichiometry of desert consumers, and they indicate that the elemental composition of animals can be useful information for identifying broad‐scale linkages between nutrient cycling and trophic interactions in terrestrial food webs.
Crab herbivory regulates re‐colonization of disturbed patches in a southwestern Atlantic salt marsh
Authors: Daleo Pedro , Alberti Juan , Iribarne Oscar
Published: February 2011

Recent work exploring the effects of physical stress and herbivory on secondary succession in estuarine plant communities agrees with basic stress models and reveal that herbivory is an important force in brackish and oligohaline marshes but negligible in physically stressful salt marshes. In these systems, herbivores are terrestrial, and thus negatively affected by the same stressful factors that affect marsh plants (i.e. frequent flooding or high salinities). We evaluated the effects of a marine herbivore (i.e. the crab Neohelice granulata) on plant secondary succession in a southwestern Atlantic salt marsh. Field surveys revealed that disturbance‐generated bare patches have harsh physical conditions and that their edges suffer higher herbivore pressure compared to the marsh matrix. A factorial experiment demonstrated that asexual expansion of the surrounding plants is the only possible mechanism to re‐colonize disturbed patches and that crab exclusion can increase this colonization rate by more than 30 times. Our results show that even in highly stressful environments, herbivores strongly impact marsh structure by regulating patch recovery. The synergism of physical stress and herbivory may make plant succession an extremely slow process and lead to the prevalence of bare areas.
Experimental evidence for host preference in a tick parasitizing songbird nestlings
Authors: Heylen Dieter J. A. , Matthysen Erik
Published: February 2011

Mechanisms of host preference in ectoparasites are important to the understanding of host‐parasite interactions. Since ectoparasites negatively affect the condition of their hosts, while the hosts’ condition itself may affect the parasites’ choice, separating the factors that drive host preference from parasite impact asks for experiments. We combined the data of two choice experiments to investigate the preference of the nidicolous tickIxodes arboricolawhen exposed to the nestlings of a passerine bird (Parus major). In the first experiment, in which complete broods at hatching were exposed to an ecologically relevant number of ticks, the relationship between tick loads and nestlings’ developmental status was characterized by a distribution with the highest tick loads on the more developed nestlings. Host preference became more apparent at a smaller brood size, suggesting a role for host density. In a second experiment we evaluated host choice in a pairwise choice experiment, exposing pairs of siblings with contrasting developmental status to eight ticks. In the first and the second pair, a median developed nestling was linked with the most developed and the least developed nestling, respectively. Seventy‐two h after tick exposure we measured the innate constitutive humoral immunity and haematocrit. No differences were found in innate immunity, but the least developed nestlings had on average a lower haematocrit than the median and most developed nestlings. Significantly fewer ticks attached on the least developed nestling compared to the median nestling, and this difference was more pronounced when the innate immunity of the median developed nestling was higher. No difference in tick load was found among the median and best developed nestlings. The linkage between host preference and host physiological condition provide further insight in the mechanisms driving ectoparasite aggregation, which is important for the population dynamics of host, ticks and tick‐transmitted pathogens.
Life history strategy in herbaceous perennials: inferring demographic patterns from the aboveground dynamics of a primarily subterranean, myco‐heterotrophic orchid
Authors: Shefferson Richard P. , McCormick Melissa K. , Whigham Dennis F. , O'Neill John P.
Published: February 2011

Myco‐heterotrophs are non‐photosynthetic plants that parasitize mycorrhizal fungi for their nutritional requirements, especially carbon. Because green plants sprout both to photosynthesize and to reproduce, the lack of photosynthesis in myco‐heterotrophs suggests that these plants need only to sprout to reproduce. Further, they may be long‐lived, with fitness favoring high, stable survival over frequent reproduction and leading to size‐biased reproduction. We hypothesized that sprouting would be rare and would always lead to flowering in a ten‐year monitoring study of a myco‐heterotrophic plant, the autumn coral root Corallorhiza odontorhiza. We also postulated that these plants would exhibit strong size‐based flowering patterns. We tested these hypotheses by parameterizing a variety of mark–recapture models of survival, fecundity, and demographic transitions among two life history stages: flowering and non‐sprouting (vegetatively dormant). We further developed and tested novel models estimating the influence of reproduction on demographic transitions one, two, and three years after flowering. Our results suggested that this population is typically subterranean, with only a small proportion of living plants actually sprouting in any given year. Plants typically flowered and fruited when they sprouted (flowering frequency > 0.99), supporting our first hypothesis that sprouting occurs only in concert with reproduction. We also found that reproduction was associated with long‐term reproductive demographic impacts – plants that flowered more in the past three years were more likely to continue doing so than those that flowered only once. Our use of ‘memory’ mark–recapture models, in which transitions across years are allowed to vary with demographic events occurring across several previous years, proved a powerful means of testing for their long‐term impacts of reproductive events.
Competition–colonization dynamics of spore‐feeding beetles on the long‐lived bracket fungi Ganoderma in New Zealand native forest
Authors: Kadowaki Kohmei , Leschen Richard A. B. , Beggs Jacqueline R.
Published: February 2011

We investigated the competition–colonization dynamics of three species of spore‐feeding beetles on wood‐decaying bracket fungi, Ganoderma spp., in New Zealand. One beetle species (Holopsis sp. 1) was a pore‐tube specialist hypothesized to be superior in exploitative competition; the other two (Zearagytodes maculifer and Holopsis sp. 2) were surface grazers. We surveyed beetle abundance, daily spore release per square centimetre, pore surface area, and environmental variables over 30 patches (sporocarps) monthly for one year. We constructed a competitive‐interaction web by fitting models to the cross‐sectional resource–multiconsumer data. We compared flight behaviour and the associated physiological traits of beetles in wind tunnel experiments, and morphological characters. An examination of the competition–colonization dynamics found (1) the competitive equivalence of Holopsis sp. 1 to Z. maculifer and superiority to Holopsis sp. 2; (2) a reduced population persistence time of Z. maculifer that results from the dominance of Holopsis sp. 1; (3) the dominance of Z. maculifer and Holopsis sp. 1 in larger patches and that of Holopsis sp. 2 in smaller patches; (4) a greater spatial extent of population synchrony in Z. maculifer than in the Holopsis spp.; and (5) more frequent departures (takeoffs) of Z. maculifer than of Holopsis spp., concordant with its greater development of flight muscles and longer hindwing. These beetles may coexist through two types of spatial niche partitioning, each of which explains the pairwise coexistence of competitors but not the coexistence of the three species: Z. maculifer can evade competition with Holopsis sp. 1 by flying frequently or strongly to colonize distant patches, whereas Holopsis sp. 2 can dominate only in smaller and newly emergent patches until the arrival of Holopsis sp. 1.
A new method for the visualization and quantification of internal skin elasticity by ultrasound imaging
Authors: Osanai Osamu , Ohtsuka Mayumi , Hotta Mitsuyuki , Kitaharai Takashi , Takema Yoshinori
Published: February 2011

Background/purpose: Skin elasticity has been assessed previously only in the surface layer. We developed a new method that uses tissue strain imaging (TSI) technology, and the aim of this study was to test this new method to assess internal skin elasticity.

Methods: Using a pressure device with a 12 MHz ultrasound transducer, constant and linear compressions were applied to the cheek skin of 35 volunteers (aged: 20–60 years). The elasticity of each layer (dermis, subcutaneous and muscle) was measured and analyzed using the TSI application software incorporated into the Toshiba Aplio™ XV ultrasound system. A skin tissue‐equivalent phantom, which is a block of material with the acoustic velocity (1530 m/s) of human skin, was collaboratively developed by OST Inc. This phantom was placed between the skin and the transducer as a reference material.

Results: Skin elasticity was clearly visualized and quantified in each layer of the skin. Age‐dependent decreases in elasticity were determined in all layers of the skin. Among the three internal skin layers, the highest elasticity was determined in the subcutaneous layer followed by the muscle layer.

Conclusion: These findings support the validity and sensitivity of the TSI method to assess the elasticity of various layers of skin.
Reversible Photoswitchable DRONPA‐s Monitors Nucleocytoplasmic Transport of an RNA‐Binding Protein in Transgenic Plants
Authors: Lummer Martina , Humpert Fabian , Steuwe Christian , Caesar Katharina , Schüttpelz Mark , Sauer Markus , Staiger Dorothee
Published: February 2011

Fluorescent reporter proteins that allow repeated switching between a fluorescent and a non‐fluorescent state are novel tools for monitoring intracellular protein trafficking. A codon‐optimized variant of the reversibly photoswitchable fluorescent protein DRONPA was designed for the use in transgenic Arabidopsis plants. Its codon usage is also well adapted to the mammalian codon usage. The synthetic protein, DRONPA‐s, shows photochemical properties and switching behavior comparable to that of the original DRONPA from Pectiniidae both in vitro and in vivo. DRONPA‐s fused to the RNA‐binding protein AtGRP7 (Arabidopsis thaliana glycine‐rich RNA‐binding protein 7) under control of the endogenous AtGRP7 promoter localizes to cytoplasm, nucleoplasm and nucleolus of transgenic Arabidopsis plants. To monitor the intracellular transport dynamics of AtGRP7‐DRONPA‐s, we set up a single‐molecule sensitive confocal fluorescence microscope. Fluorescence recovery after selective photoswitching experiments revealed that AtGRP7‐DRONPA‐s reaches the nucleus by carrier‐mediated transport. Furthermore, photoactivation experiments showed that AtGRP7‐DRONPA‐s is exported from the nucleus. Thus, AtGRP7 is a nucleocytoplasmic shuttling protein. Our results show that the fluorescent marker DRONPA‐s is a versatile tool to track protein transport dynamics in stably transformed plants.
Organization and Assembly of the TRAPPII Complex
Authors: Choi Catherine , Davey Michael , Schluter Cayetana , Pandher Preet , Fang Yuan , Foster Leonard J. , Conibear Elizabeth
Published: February 2011

Current models suggest that TRAPP tethering complexes exist in two forms. Whereas the seven‐subunit TRAPPI complex mediates ER‐to‐Golgi transport, TRAPPII contains three additional subunits (Trs65, Trs120 and Trs130) and is required for distinct tethering events at Golgi membranes. It is not clear how TRAPPII assembly is regulated. Here, we show that Tca17 is a fourth TRAPPII‐specific component, and that Trs65 and Tca17 interact with distinct domains of Trs130 and make different contributions to complex assembly. Whereas Tca17 promotes the stable association of TRAPPII‐specific subunits with the core complex, Trs65 stabilizes TRAPPII in an oligomeric form. We show that Trs85, which was previously reported to be a subunit of both TRAPPI and TRAPPII, is not associated with the TRAPPII complex in yeast. However, we find that proteins related to Trs85, Trs65 and Tca17 are part of the same TRAPP complex in mammalian cells. These findings have implications for models of TRAPP complex formation and suggest that TRAPP complexes may be organized differently in yeast and mammals.
Need for quality control for aEEG monitoring of the preterm infant: a 2‐year experience
Authors: Griesmaier Elke , Neubauer Vera , Ralser Elisabeth , Trawöger Rudolf , Kiechl‐Kohlendorfer Ursula , Keller Matthias
Published: February 2011

Aim:  To establish and apply a questionnaire for the evaluation of amplitude‐integrated electroencephalogram (aEEG) with respect to practicability and feasibility in the NICU, to reveal strategies for improvements in daily use and to investigate the level of staff know‐how with regard to performance and evaluation of bedside aEEG for the purpose of quality control.

Methods:  Amplitude‐integrated electroencephalogram was routinely applied in preterm infants below 32 weeks of gestational age for a period of 2 years. Practicability, feasibility and the level of know‐how with regard to aEEG were assessed using a multiple‐choice questionnaire.

Results:  Major problems in the use of aEEG in preterm infants were identified as time needed for placement and frequent readjustment of electrodes. Quality control showed the following problems: seizure activity was correctly diagnosed in 60.0%, discontinuous (DC) background in 45.5% and burst suppression (BS) in 41.8% of patients. Overall, BS and DC were the patterns most frequently interpreted incorrectly.

Conclusion:  Amplitude‐integrated electroencephalogram is frequently used in neonatology. In preterm infants with several challenges, repeated theoretical and practical trainings as well as quality control are needed in order for aEEG to become a routinely used monitoring instrument in daily preterm care.
Blood tests and histological correlates in children with eosinophilic oesophagitis
Authors: Marlais M , Francis ND , Fell JME , Rawat DJ
Published: February 2011

Aim:  To determine the relationship between blood tests and oesophageal histology in Eosinophilic oesophagitis (EoE).

Methods:  All children diagnosed with EoE at one hospital from 2000 to 2009 were considered for inclusion in this study. Three blood test results were analysed, blood eosinophil count, serum total immunoglobulin E (IgE) and radioallergosorbent tests (RAST) to common food allergens. Oesophageal histology was prospectively re‐reviewed, and mean eosinophil counts were enumerated. Blood test results were correlated with oesophageal eosinophil counts using Spearman’s rank test.

Results:  Forty children (70% boys) were included in this study, median age at diagnosis 6.5 years (range 0–15). At the time of diagnosis, 78% of children had a raised blood eosinophil count, 90% had a raised serum total IgE and 83% had one or more positive RAST tests. The mean oesophageal eosinophil count was significantly correlated with both blood eosinophil count (p = 0.008) and serum total IgE level (p = 0.008).

Conclusion:  This study shows that blood tests are often abnormal in children with EoE at the time of diagnosis. Our data demonstrate an association between histological abnormalities and blood test results in children with EoE.
Normal visual evoked potentials in preschool children born small for gestational age
Authors: Nilsson Josefin , Dahlgren Jovanna , Karlsson Ann‐Katrine , Grönlund Marita Andersson
Published: February 2011

Aim:  Previous studies have shown visual evoked potential (VEP) abnormalities in infants and animals born small for gestational age (SGA) compared with controls. The current exploratory study aims to investigate whether VEP abnormalities persist in older ages.

Methods:  Pattern VEP latencies were obtained in 21 children (11 girls, 10 boys), born SGA and moderately preterm, at an average age of 5 years and 8 months. Fifty‐one children (24 girls, 27 boys, mean age of 5 years and 7 months), also born moderately preterm but with normal height and weight at birth, served as controls

Results:  Visual evoked potential results showed no significant differences in latency between children born SGA and controls born appropriate for gestational age (AGA) for either binocular stimulation, right eye or left eye stimulation.

Conclusions:  Our findings do not indicate any differences in VEP latency at preschool age for children born SGA compared with children born AGA. The results may support previous studies, suggesting that children born SGA show accelerated neurophysiologic maturation during their first year of life and that previously delayed VEP latencies after catch‐up stay unchanged compared with controls.
Parental smoking, nasal resistance and rhinitis in children
Authors: Virkkula P , Liukkonen K , Suomalainen AK , Aronen ET , Kirjavainen T , Pitkäranta A
Published: February 2011

Aim:  To determine whether parent‐reported perennial rhinitis or objectively measured nasal resistance is more common in children from smoking families. To assess tonsillar size, nasopharyngeal airway and upper airway surgery frequency in children with smoking and non‐smoking parents.

Methods:  Ninety‐five children (age 3–6 years, median 68 months) participated in this prospective cross‐sectional clinical study. History of nasal symptoms was obtained, and all underwent an ear–nose–throat examination, anterior rhinomanometry and a lateral cephalogram. Regular smoking by either parent and their child’s snoring was inquired about with a parental questionnaire. We compared children with a parental smoker and children without a parental smoker in the family.

Results:  Smoking in the family led to increased risk for perennial rhinitis in the children up to 2.76‐fold (aOR, 95%CI 1.00–7.67), but with no difference in nasal resistance between children from smoking and non‐smoking households. Neither tonsillar size, nasopharyngeal airway nor upper airway surgery was associated with parental smoking.

Conclusions:  Parental smoking is associated with symptoms of perennial rhinitis in children. The possible role of environmental tobacco smoke should be taken into account in parent counselling and in evaluation of children being treated for symptoms of rhinitis and nasal obstruction.
CD4+CD25high Treg cells in peripheral blood during remission and exacerbation of allergic asthma in children
Authors: Pumputiene Ingrida , Emuzyte Regina , Siaurys Almantas , Tamosiunas Vytas , Valiulis Arunas
Published: February 2011

Aim:  To determine the percentage of CD4+CD25high Treg cells in peripheral blood CD4+ T cells of allergic asthmatic children during disease remission and exacerbation.

Methods:  Peripheral blood mononuclear cells (PBMC) and serum samples were collected from 6‐ to 11‐year‐old children with mild‐to‐moderate allergic asthma (n = 34) and from healthy controls (n = 15). CD4+CD25high T cells in PBMC were detected by flow cytometry. Total and specific IgE in serum were analysed by enzyme‐amplified chemiluminescence, and IL‐2 was measured by ELISA.

Results:  There was no significant difference in CD4+CD25high T‐cell proportions between asthmatic children in exacerbation and remission as compared with controls. CD4+CD25high T‐cell percentages were not correlated with total and specific IgE. IL‐2 was elevated in both disease remission and exacerbation but did not correlate significantly with CD4+CD25high T‐cell percentages.

Conclusion:  CD4+CD25high T‐cell proportion in the peripheral blood of total CD4+ T cells is not reduced in children with allergic IgE‐mediated asthma and does not differ between disease remission and exacerbation.