bluuebunny/crossref_metadata_2025 huggingface dataset:
Cryo‐SEM specimen preparation under controlled temperature and concentration conditions
Authors: ISSMAN L. , TALMON Y.
Published: January 2012

Cryogenic temperature scanning electron microscopy (cryo‐SEM) is an excellent technique for imaging liquid and semi‐liquid materials of high vapour pressure, which are highly viscous or contain large (>0.5 μm) aggregates, in which nanometric details are to be studied. However, so far there have been no adequate tools for controlled cryo‐specimen preparation. The specimen preparation stage is critical, because most of those samples are very sensitive to concentration and temperature changes, leading to nanostructural artefacts in the specimens. We designed and built a system for easy and reliable cryo‐SEM specimen preparation under controlled conditions of fixed temperature and humidity. We describe this new methodology, and demonstrate its applicability, by showing imaging data of three liquid material systems. We have studied carbon nanotubes (CNTs) dispersions in superacid. We also characterized a number of systems made of water/isooctane/nonionic and cationic surfactant that showed different microemulsion phases as function of the system composition and temperature. In all of the examples given, we demonstrate artefact‐ and contamination‐free specimens, which have preserved their native nanostructure. Our new system paves the way for a new methodology for the newly emerging field of cryo‐SEM.
Proteomics in evolutionary ecology: linking the genotype with the phenotype
Authors: DIZ ANGEL P. , MARTÍNEZ‐FERNÁNDEZ MÓNICA , ROLÁN‐ALVAREZ EMILIO
Published: January 2012

The study of the proteome (proteomics), which includes the dynamics of protein expression, regulation, interactions and its function, has played a less prominent role in evolutionary and ecological investigations in comparison with the study of the genome and transcriptome. There are, however, a number of arguments suggesting that this situation should change. First, the proteome is closer to the phenotype than the genome or the transcriptome, and as such may be more directly responsive to natural selection, and thus closely linked to adaptation. Second, there is evidence of a low correlation between protein and transcript expression levels across genes in many different organisms. Finally, there have been some recent important technological improvements in proteomics methods that make them feasible, practical and useful to address a wide range of evolutionary questions even in nonmodel organisms. The different proteomic methods, their limitations and problems when interpreting empirical data are described and discussed. In addition, the proteomic literature pertaining to evolutionary ecology is reviewed with examples, and potential applications of proteomics in a variety of evolutionary contexts are outlined. New proteomic research trends such as the study of posttranslational modifications and protein–protein interactions, as well as the combined use of the different ‐omics approaches, are discussed in relation to the development of a more functional and integrated perspective, needed for achieving a more comprehensive knowledge of evolutionary change.
Monitoring adaptive genetic responses to environmental change
Authors: HANSEN MICHAEL M. , OLIVIERI ISABELLE , WALLER DONALD M. , NIELSEN EINAR E. ,   The GeM Working Group
Published: January 2012

Widespread environmental changes including climate change, selective harvesting and landscape alterations now greatly affect selection regimes for most organisms. How animals and plants can adapt to these altered environments via contemporary evolution is thus of strong interest. We discuss how to use genetic monitoring to study adaptive responses via repeated analysis of the same populations over time, distinguishing between phenotypic and molecular genetics approaches. After describing monitoring designs, we develop explicit criteria for demonstrating adaptive responses, which include testing for selection and establishing clear links between genetic and environmental change. We then review a few exemplary studies that explore adaptive responses to climate change in Drosophila, selective responses to hunting and fishing, and contemporary evolution in Daphnia using resurrected resting eggs. We further review a broader set of 44 studies to assess how well they meet the proposed criteria, and conclude that only 23% fulfill all criteria. Approximately half (43%) of these studies failed to rule out the alternative hypothesis of replacement by a different, better‐adapted population. Likewise, 34% of the studies based on phenotypic variation did not test for selection as opposed to drift. These shortcomings can be addressed via improved experimental designs and statistical testing. We foresee monitoring of adaptive responses as a future valuable tool in conservation biology, for identifying populations unable to evolve at sufficiently high rates and for identifying possible donor populations for genetic rescue. Technological advances will further augment the realization of this potential, especially next‐generation sequencing technologies that allow for monitoring at the level of whole genomes.
FcγRIIa Polymorphism and Anti‐Malaria‐Specific IgG and IgG Subclass Responses in Populations Differing in Susceptibility to Malaria in Burkina Faso
Authors: Cherif M. K. , Sanou G. S. , Maiga B. , Israelsson E. , Ouédraogo A. L. , Bougouma E. C. , Diarra A. , Ouédraogo A. , Ouattara A. S. , Troye‐Blomberg M. , Dolo A. , Cavanagh D. R. , Theisen M. , Modiano D. , Sirima S. B. , Nebié I.
Published: January 2012

Abstract FcγRIIa is known to be polymorphic; and certain variants are associated with different susceptibilities to malaria. Studies involving the Fulani ethnic group reported an ethnic difference in FcγRIIa‐R131H genotype frequencies between the Fulani and other sympatric groups. No previous studies have addressed these questions in Burkina Faso. This study aimed to assess the influence of FcγRIIa‐R131H polymorphism on anti‐falciparum malaria IgG and IgG subclass responses in the Fulani and the Mossi ethnic groups living in Burkina Faso. Healthy adults more than 20 years old belonging to the Mossi or the Fulani ethnic groups were enrolled for the assessment of selected parasitological, immunological and genetic variables in relation to their susceptibility to malaria. The prevalence of the Plasmodium falciparum infection frequency was relatively low in the Fulani ethnic group compared to the Mossi ethnic group. For all tested antigens, the Fulani had higher antibody levels than the Mossi group. In both ethnic groups, a similar distribution of FcγRIIa R131H polymorphism was found. Individuals with the R allele of FcγRIIa had higher antibody levels than those with the H allele. This study confirmed that malaria infection affected less the Fulani group than the Mossi group. FcγRIIa‐R131H allele distribution is similar in both ethnic groups, and higher antibody levels are associated with the FcγRIIa R allele compared to the H allele.
Calcretes, fluviolacustrine sediments and subsidence patterns in Permo‐Triassic salt‐walled minibasins of the south Urals, Russia
Authors: NEWELL ANDREW J. , BENTON MICHAEL J. , KEARSEY TIMOTHY , TAYLOR GRAEME , TWITCHETT RICHARD J. , TVERDOKHLEBOV VALENTIN P.
Published: January 2012

The south Uralian foreland basin forms part of the giant, yet sparsely documented, PreCaspian salt tectonic province. The basin can potentially add much to the understanding of fluviolacustrine sedimentation within salt‐walled minibasins, where the literature has been highly reliant on only a few examples (such as the Paradox Basin of Utah). This paper describes the Late Permian terrestrial fill of the Kul’chumovo salt minibasin near Orenburg in the south Urals in which sediments were deposited in a range of channel, overbank and lacustrine environments. Palaeomagnetic stratigraphy shows that, during the Late Permian, the basin had a relatively slow and uniform subsidence pattern with widespread pedogenesis and calcrete development. Angular unconformities or halokinetic sequence boundaries cannot be recognized within the relatively fine‐grained fill, and stratigraphic and spatial variations in facies are therefore critical to understanding the subsidence history of the salt minibasin. Coarse‐grained channel belts show evidence for lateral relocation within the minibasin while the development of a thick stack of calcrete hardpans indicates that opposing parts of the minibasin became largely inactive for prolonged periods (possibly in the order of one million years). The regular vertical stacking of calcrete hardpans within floodplain mudstones provides further evidence that halokinetic minibasin growth is inherently episodic and cyclical.
Sea‐level rise, depth‐dependent carbonate sedimentation and the paradox of drowned platforms
Authors: KIM WONSUCK , FOUKE BRUCE W. , PETTER ANDREW L. , QUINN TERRENCE M. , KERANS CHARLES , TAYLOR FRED
Published: January 2012

A mathematical model of carbonate platform evolution is presented in which depth‐dependent carbonate growth rates determine platform‐top accumulation patterns in response to rising relative sea‐level. This model predicts that carbonate platform evolution is controlled primarily by the water depth and sediment accumulation rate conditions at the onset of relative sea‐level rise. The long‐standing ‘paradox of a drowned platform’ arose from the observation that maximum growth rate potentials of healthy platforms are faster than those of relative sea‐level rise. The model presented here demonstrates that a carbonate platform could be drowned during a constant relative sea‐level rise whose rate remains less than the maximum carbonate production potential. This scenario does not require environmental changes, such as increases in nutrient supply or siliciclastic sedimentation, to have taken place. A rate of relative sea‐level rise that is higher than the carbonate accumulation rate at the initial water depth is the only necessary condition to cause continuous negative feedbacks to the sediment accumulation rates. Under these conditions, the top of the carbonate platform gradually deepens until it is below the active photic zone and drowns despite the strong maximum growth potential of the carbonate production factory. This result effectively resolves the paradox of a drowned carbonate platform. Test modelling runs conducted with 2·5 m and 15 m initial sea water depths at bracketed rates of relative sea‐level rise have determined how fast the system catches up and maintains the ‘keep‐up’ phase. This is the measure of time necessary for the basin to respond fully to external forcing mechanisms. The duration of the ‘catch‐up’ phase of platform response (termed ‘carbonate response time’) scales with the initial sea water depth and the platform‐top aggradation rate. The catch‐up duration can be significantly elongated with an increase in the rate of relative sea‐level rise. The transition from the catch‐up to the keep‐up phases can also be delayed by a time interval associated with ecological re‐establishment after platform flooding. The carbonate model here employs a logistical equation to model the colonization of carbonate‐producing marine organisms and captures the initial time interval for full ecological re‐establishment. This mechanism prevents the full extent of carbonate production to be achieved at the incipient stage of relative sea‐level rise. The increase in delay time due to the carbonate response time and self‐organized processes associated with biological colonization increase the chances for platform drowning due to deepening of water depth (> ca 10 m). Furthermore this implies a greater likelihood for an autogenic origin for high‐frequency cyclic strata than has been estimated previously.
Reconstruction of a human mitochondrial complex I mutation in the unicellular green alga Chlamydomonas
Authors: Larosa Véronique , Coosemans Nadine , Motte Patrick , Bonnefoy Nathalie , Remacle Claire
Published: January 2012

Defects in complex I (NADH:ubiquinone oxidoreductase (EC 1.6.5.3)) are the most frequent cause of human respiratory disorders. The pathogenicity of a given human mitochondrial mutation can be difficult to demonstrate because the mitochondrial genome harbors large numbers of polymorphic base changes that have no pathogenic significance. In addition, mitochondrial mutations are usually found in the heteroplasmic state, which may hide the biochemical effect of the mutation. We propose that the unicellular green alga Chlamydomonas could be used to study such mutations because (i) respiratory complex‐deficient mutants are viable and mitochondrial mutations are found in the homoplasmic state, (ii) transformation of the mitochondrial genome is feasible, and (iii) Chlamydomonas complex I is similar to that of humans. To illustrate this proposal, we introduced a Leu157Pro substitution into the Chlamydomonas ND4 subunit of complex I in two recipient strains by biolistic transformation, demonstrating that site‐directed mutagenesis of the Chlamydomonas mitochondrial genome is possible. This substitution did not lead to any respiratory enzyme defects when present in the heteroplasmic state in a patient with chronic progressive external ophthalmoplegia. When present in the homoplasmic state in the alga, the mutation does not prevent assembly of whole complex I (950 kDa) and the NADH dehydrogenase activity of the peripheral arm of the complex is mildly affected. However, the NADH:duroquinone oxidoreductase activity is strongly reduced, suggesting that the substitution could affect binding of ubiquinone to the membrane domain. The in vitro defects correlate with a decrease in dark respiration and growth rate in vivo.
Non‐random distribution of extensive chromosome rearrangements in Brassica napus depends on genome organization
Authors: Nicolas Stéphane D. , Monod Hervé , Eber Frédérique , Chèvre Anne‐Marie , Jenczewski Eric
Published: January 2012

Chromosome rearrangements are common, but their dynamics over time, mechanisms of occurrence and the genomic features that shape their distribution and rate are still poorly understood. We used allohaploid Brassica napus (AC, n = 19) as a model to analyze the effect of genomic features on the formation and diversity of meiotically driven chromosome rearrangements. We showed that allohaploid B. napus meiosis leads to extensive new structural diversity. Almost every allohaploid offspring carried a unique combination of multiple rearrangements throughout the genome, and was thus structurally differentiated from both its haploid parent and its sister plants. This large amount of genome reshuffling was remarkably well‐tolerated in the heterozygous state, as neither male nor female fertility were strongly reduced, and meiosis behavior was normal in most cases. We also used a quantitative statistical model, which accounted for 75% of the observed variation in rearrangement rates, to show that the distribution of meiotically driven chromosome rearrangements was not random but was shaped by three principal genomic features. In descending order of importance, the rate of marker loss increased strongly with genetic distance from the centromere, the degree of collinearity between chromosomes, and the genome of origin (A < C). Overall, our results demonstrate that B. napus accumulates a large number of genetic changes, but these rearrangements are not randomly distributed in the genome. The structural genetic diversity produced by the allohaploid pathway and its role in the evolution of polyploid species compared to diploid meiosis are discussed.
Visual marker and Agrobacterium‐delivered recombinase enable the manipulation of the plastid genome in greenhouse‐grown tobacco plants
Authors: Tungsuchat‐Huang Tarinee , Maliga Pal
Published: January 2012

Successful manipulation of the plastid genome (ptDNA) has been carried out so far only in tissue‐culture cells, a limitation that prevents plastid transformation being applied in major agronomic crops. Our objective is to develop a tissue‐culture independent protocol that enables manipulation of plastid genomes directly in plants to yield genetically stable seed progeny. We report that in planta excision of a plastid aurea bar gene (bar au) is detectable in greenhouse‐grown plants by restoration of the green pigmentation in tobacco leaves. The P1 phage Cre or PhiC31 phage Int site‐specific recombinase was delivered on the Agrobacterium T‐DNA injected at the axillary bud site, resulting in the excision of the target‐site flanked marker gene. Differentiation of new apical meristems was forced by decapitating the plants above the injection site. The new shoot apex that differentiated at the injection site contained bar au‐free plastids in 30–40% of the injected plants, of which 7% transmitted the bar au‐free plastids to the seed progeny. The success of obtaining seed with bar au‐free plastids depended on repeatedly forcing shoot development from axillary buds, a process that was guided by the size and position of green sectors in the leaves. The success of in planta plastid marker excision proved that manipulation of the plastid genomes is feasible within an intact plant. Extension of the protocol to in planta plastid transformation depends on the development of new protocols for the delivery of transforming DNA encoding visual markers.
Inducible NAD overproduction in Arabidopsis alters metabolic pools and gene expression correlated with increased salicylate content and resistance to Pst‐AvrRpm1
Authors: Pétriacq Pierre , de Bont Linda , Hager Jutta , Didierlaurent Laure , Mauve Caroline , Guérard Florence , Noctor Graham , Pelletier Sandra , Renou Jean‐Pierre , Tcherkez Guillaume , Gakière Bertrand
Published: January 2012

Plant development and function are underpinned by redox reactions that depend on co‐factors such as nicotinamide adenine dinucleotide (NAD). NAD has recently been shown to be involved in several signalling pathways that are associated with stress tolerance or defence responses. However, the mechanisms by which NAD influences plant gene regulation, metabolism and physiology still remain unclear. Here, we took advantage of Arabidopsis thaliana lines that overexpressed the nadC gene from E. coli, which encodes the NAD biosynthesis enzyme quinolinate phosphoribosyltransferase (QPT). Upon incubation with quinolinate, these lines accumulated NAD and were thus used as inducible systems to determine the consequences of an increased NAD content in leaves. Metabolic profiling showed clear changes in several metabolites such as aspartate‐derived amino acids and NAD‐derived nicotinic acid. Large‐scale transcriptomic analyses indicated that NAD promoted the induction of various pathogen‐related genes such as the salicylic acid (SA)‐responsive defence marker PR1. Extensive comparison with transcriptomic databases further showed that gene expression under high NAD content was similar to that obtained under biotic stress, eliciting conditions or SA treatment. Upon inoculation with the avirulent strain of Pseudomonas syringae pv. tomato Pst‐AvrRpm1, the nadC lines showed enhanced resistance to bacteria infection and exhibited an ICS1‐dependent build‐up of both conjugated and free SA pools. We therefore concluded that higher NAD contents are beneficial for plant immunity by stimulating SA‐dependent signalling and pathogen resistance.
In vivo visualization of RNA in plants cells using the λN22 system and a GATEWAY‐compatible vector series for candidate RNAs
Authors: Schönberger Johannes , Hammes Ulrich Z. , Dresselhaus Thomas
Published: January 2012

The past decade has seen a tremendous increase in RNA research, which has demonstrated that RNAs are involved in many more processes than were previously thought. The dynamics of RNA synthesis towards their regulated activity requires the interplay of RNAs with numerous RNA binding proteins (RBPs). The localization of RNA, a mechanism for controlling translation in a spatial and temporal fashion, requires processing and assembly of RNA into transport granules in the nucleus, transport towards cytoplasmic destinations and regulation of its activity. Compared with animal model systems little is known about RNA dynamics and motility in plants. Commonly used methods to study RNA transport and localization are time‐consuming, and require expensive equipment and a high level of experimental skill. Here, we introduce the λN22 RNA stem‐loop binding system for the in vivo visualization of RNA in plant cells. The λN22 system consists of two components: the λN22 RNA binding peptide and the corresponding box‐B stem loops. We generated fusions of λN22 to different fluorophores and a GATEWAY vector series for the simple fusion of any target RNA 5′ or 3′ to box‐B stem loops. We show that the λN22 system can be used to detect RNAs in transient expression assays, and that it offers advantages compared with the previously described MS2 system. Furthermore, the λN22 system can be used in combination with the MS2 system to visualize different RNAs simultaneously in the same cell. The toolbox of vectors generated for both systems is easy to use and promises significant progress in our understanding of RNA transport and localization in plant cells.
Programmed cell death in Ricinus and Arabidopsis: the function of KDEL cysteine peptidases in development
Authors: Hierl Georg , Vothknecht Ute , Gietl Christine
Published: January 2012

Programmed cell death (PCD) in plants is a prerequisite for development as well as seed and fruit production. It also plays a significant role in pathogen defense. A unique group of papain‐type cysteine endopeptidases, characterized by a C‐terminal endoplasmic reticulum (ER) retention signal (KDEL CysEP), is involved in plant PCD. Genes for these endopeptidases have been sequenced and analyzed from 25 angiosperms and gymnosperms. They have no structural relationship to caspases involved in mammalian PCD and homologs to this group of plant cysteine endopeptidases have not been found in mammals or yeast. In castor beans (Ricinus communis), the CysEP is synthesized as pre‐pro‐enzyme. The pro‐enzyme is transported to the cytosol of cells undergoing PCD in ER‐derived vesicles called ricinosomes. These vesicles release the mature CysEP in the final stages of organelle disintegration triggered by acidification of the cytoplasm resulting from the disruption of the vacuole. Mature CysEP digests the hydroxyproline (Hyp)‐rich proteins (extensins) that form the basic scaffold of the plant cell wall. The KDEL CysEPs accept a wide variety of amino acids at the active site, including the glycosylated Hyp residues of the extensins. In Arabidopsis, three KDEL CysEPs (AtCEP1, AtCEP2 and AtCEP3) are expressed in tissues undergoing PCD. In transgenic Arabidopsis plants expressing β‐glucuronidase under the control of the promoters for these three genes, cell‐ and tissue‐specific activities were mapped during seedling, flower and seed development. KDEL CysEPs participate in the collapse of tissues in the final stage of PCD and in tissue re‐modeling such as lateral root formation.
Characterization of the early response of the orchid, Phalaenopsis amabilis, to Erwinia chrysanthemi infection using expression profiling
Authors: Fu Shih‐Feng , Tsai Tsung‐Mu , Chen Ying‐Ru , Liu Ching‐Pei , Haiso Lin‐June , Syue Li‐Hsin , Yeh Hsin‐Hung , Huang Hao‐Jen
Published: January 2012

Erwinia chrysanthemi is a devastating bacterial pathogen in Phalaenopsis amabilis and causes soft‐rotting disease by secretion of cell wall‐degrading enzymes. However, the molecular mechanisms underlying the interaction of P. amabilis with E. chrysanthemi remain elusive. In this study, early molecular events of the plant in response to the pathogen attack were investigated. The alteration in reactive oxygen species accumulation and peroxidase activity occurred at the site of infection. Subsequently, a systematic sequencing of expressed sequence tags (ESTs) using suppression subtractive hybridization (SSH) was performed to obtain the first global picture of the assembly of genes involved in the pathogenesis. The majority of the SSH clones showed a high identity with genes coding for proteins that have known roles in redox homeostasis, responses to pathogens and metabolism. A notable number of the SSH clones were those encoding WRKY, MYB and basic leucine zipper transcription factors, indicating the stimulation of intracellular signal transduction. An orchid gene encoding trans‐2‐enoyl‐CoA reductase (ECR) was the most abundant transcripts in the EST library. ECR is an enzyme catalyzing the very long chain fatty acids (VLCFAs) biosynthesis, and the full‐length cDNA of the ECR gene (PaECR1) was obtained. Functional analysis of PaECR1 was conducted by virus‐induced gene silencing to knock down the gene expression in P. amabilis. The PaECR1‐silenced plants were more susceptible to E. chrysanthemi infection, implying potential roles for VLCFAs in the pathogenesis. In summary, the pathogen‐responsive gene expression profiles facilitated a more comprehensive view of the molecular events that underlie this economically important plant–pathogen interaction.
Host conservatism, host shifts and diversification across three trophic levels in two Neotropical forests
Authors: WILSON J. S. , FORISTER M. L. , DYER L. A. , O’CONNOR J. M. , BURLS K. , FELDMAN C. R. , JARAMILLO M. A. , MILLER J. S. , RODRÍGUEZ‐CASTAÑEDA G. , TEPE E. J. , WHITFIELD J. B. , YOUNG B.
Published: January 2012

Host–parasite systems have been models for understanding the connection between shifts in resource use and diversification. Despite theoretical expectations, ambiguity remains regarding the frequency and importance of host switches as drivers of speciation in herbivorous insects and their parasitoids. We examine phylogenetic patterns with multiple genetic markers across three trophic levels using a diverse lineage of geometrid moths (Eois), specialist braconid parasitoids (Parapanteles) and plants in the genusPiper. Host–parasite associations are mapped onto phylogenies, and levels of cospeciation are assessed. We find nonrandom patterns of host use within both the moth and wasp phylogenies. The moth–plant associations in particular are characterized by small radiations of moths associated with unique host plants in the same geographic area (i.e. closely related moths using the same host plant species). We suggest a model of diversification that emphasizes an interplay of factors including host shifts, vicariance and adaptation to intraspecific variation within hosts.
Divergence of ovipositor length and egg shape in a brood parasitic bitterling fish through the use of different mussel hosts
Authors: KITAMURA J. , NAGATA N. , NAKAJIMA J. , SOTA T.
Published: January 2012

Bitterling fishes deposit their eggs on the gills of living mussels using a long ovipositor. We examined whether ovipositor length (OL) and egg shape correlated with differences in host mussel species in the family Unionidae among populations of the tabira bitterling (Acheilognathus tabira) in Japan. Bitterling populations that use mussels in the sub‐family Anodontinae possessed longer ovipositors and more elongated eggs than those using mussels of Unioninae, as expected from the difference in host size between the sub‐families (anodontine mussels are larger than unionine mussels). Based on a robust phylogeny of A. tabira populations, we demonstrated that the evolution of both OL and egg shape were correlated with host differences, but not with each other, suggesting that these traits have been selected for independently. Our study demonstrates how adaptive traits for brood parasitism may diverge with host shift due to different host availability and/or interspecific competition for hosts.
Changes in reciprocal herkogamy during the tristyly–distyly transition inOxalis alpinaincrease efficiency in pollen transfer
Authors: BAENA‐DíAZ F. , FORNONI J. , SOSENSKI P. , MOLINA‐FREANER F. E. , WELLER S. G. , PÉREZ‐ISHIWARA R. , DOMÍNGUEZ C. A.
Published: January 2012

Although the spatial separation of sexual organs within a flower (herkogamy) has been interpreted as a mechanism that promotes efficient pollen transfer, there have been few attempts to relate variation in herkogamy to probabilities of pollen flow. Here, we used a heterostylous species with variation in reciprocal herkogamy to test this hypothesis. We measured legitimate and illegitimate pollen flow with fluorescent dyes in four selected populations ofOxalis alpinacorresponding to the extremes of a previously reported evolutionary gradient from tristyly to distyly. After the breakdown of tristyly, the observed increment in reciprocal herkogamy between the long and short morphs was associated with a 30% increase in the proportion of dye received from compatible illegitimate pollinations. In all populations, the most likely effective pollen vectors were twoHeterosarusbee species. Our results support the adaptive value of reciprocal herkogamy in promoting efficient pollen transfer in heterostylous species.
The adaptive significance of mandibular symphyseal fusion in mammals
Authors: SCOTT J. E. , HOGUE A. S. , RAVOSA M. J.
Published: January 2012

The mandibular symphyseal joint is remarkably variable across major mammalian clades, ranging in adults from unfused (amphiarthrosis) to partially fused (synarthrosis) to completely ossified (synostosis). Experimental work conducted on primates suggests that greater ossification of the symphysis is a response to increased recruitment of the balancing‐side (i.e. nonchewing side) jaw‐adductor muscles during forceful unilateral biting and chewing, with increased fusion strengthening the symphysis against correspondingly elevated joint stresses. It is thus expected that species with diets composed primarily of foods that require high‐magnitude bite forces and/or repetitive loading to process will be characterized by greater degrees of symphyseal ossification than species with relatively easy‐to‐process diets (i.e. food items typified by low toughness and/or low stiffness). However, comparative support for this idea is limited. We tested this hypothesis in four dietarily diverse mammalian clades characterized by variation in symphyseal fusion – the Strepsirrhini, Marsupialia, Feliformia, and Caniformia. We scored fusion in adult specimens of 292 species, assigned each to a dietary category based on literature accounts, and tested for an association between these two variables using Pagel’s test for the correlated evolution of binary characters. Results indicate that greater fusion is associated with diets composed of resistant items in strepsirrhines, marsupials, and feliforms, providing some support for the hypothesis. However, no such relationship was detected in caniforms, suggesting that factors other than dietary mechanical properties influence symphyseal ossification. Future work should focus on such factors, as well as those that favour an unfused mandibular symphysis.
LDSO: a program to simulate pedigrees and molecular information under various evolutionary forces
Authors: Ytournel F. , Teyssèdre S. , Roldan D. , Erbe M. , Simianer H. , Boichard D. , Gilbert H. , Druet T. , Legarra A.
Published: January 2012

Simulations are a major tool to evaluate new statistical methods and optimize experimental designs in the genomic era. However, this can only be achieved when the simulations are close enough to reality, as well as diverse enough to be realistic. For mapping studies, it is thus critical to re‐create as much as possible the forces generating linkage (mutation, random drift, changes in population sizes, selection and pedigree structure) and the mechanisms producing trait genetic architecture (additivity, dominance, epistasis). We present here a computer program (ldso) simulating these phenomena. Optional outputs provide statistics on the linkage disequilibrium (LD) structure and the identity by descent between chromosomal segments, facilitating further data analyses. Furthermore, ldso enables the simulation of genomic data in known pedigrees, which sticks as precisely as possible to recent population history and structures of the long‐range LD, allowing optimization of fine‐mapping strategies.
Calla lily chlorotic spot virus from Spider Lily (Hymenocallis litteralis) and Tobacco (Nicotiana tabacum) in the South‐west of China
Authors: Liu Yating , Lu Xiuping , Zhi Long , Zheng Yuanxian , Chen Xuejiao , Xu Yue , Wu Fajing , Li Yongzhong
Published: January 2012

Leaf samples were collected from four spider lily and tobacco plants with tospovirus‐like symptoms in Yunnan province. The nucleocapsid ORFs of the four isolates were obtained by RT‐PCR, cloning and sequencing of the amplified products. Nucleotide sequences of the obtained amplicons were more than 90% identical to that of Calla lily chlorotic spot virus (CCSV) isolates deposited in the GenBank database. The virus induced systematic leaf necrosis, chlorotic lesions, rugosity and deformation on mechanically inoculated experimental hosts. This is the first report of CCSV in mainland China, and also on spider lily and tobacco.
Parrotfish mediation in coral mortality and bioerosion by the encrusting, excavating sponge Cliona tenuis
Authors: Márquez Juan Carlos , Zea Sven
Published: January 2012

The parrotfish Sparisoma viride often grazes live coral from edges undermined by the Caribbean encrusting and excavating sponge Cliona tenuis. To test whether parrotfish biting action has an effect on the dynamics of the sponge–coral interaction, we manipulated access of parrotfishes to the sponge–coral border in two species of massive corals. When parrotfish had access to the border, C. tenuis advanced significantly more slowly into the coral Siderastrea siderea than into the coral Diploria strigosa. When fish bites were prevented, sponge spread into S. siderea was further slowed down but remained the same for D. strigosa. Additionally, a thinner layer of the outer coral skeleton was removed by bioerosion when fish were excluded, a condition more pronounced in D. strigosa than in S. siderea. Thus, the speed of sponge‐spread and the extent of bioerosion by parrotfish was coral species‐dependent. It is hypothesized that coral skeleton architecture is the main variable associated with such dependency. Cliona tenuis spread is slow when undermining live S. siderea owing to the coral’s compact skeleton. The coral’s smooth and hard surface promotes a wide and shallow parrotfish bite morphology, which allows the sponge to overgrow the denuded area and thus advance slightly faster. On the less compact skeleton of the brain coral, D. strigosa, sponge spread is more rapid. This coral’s rather uneven surface sustains narrower and deeper parrotfish bites which do not facilitate the already fast sponge progress. Parrotfish corallivory thus acts synergistically with C. tenuis to further harm corals whose skeletal architecture slows sponge lateral spread. In addition, C. tenuis also appears to mediate the predator–prey fish–coral interaction by attracting parrotfish biting.
Combining echo sounding, sediment and biological data to map benthic habitats in a coastal area of the Persian Gulf
Authors: Haghi Mahsa , Savari Ahmad , Kochanian Preeta , Nabavi Mohammad Bagher , Nami Mohammad Hasan , Zakeri Mohammad , Bodaghi Mohammad
Published: January 2012

Mapping surveys of coastal benthic habitat in Qeshm Island Geopark, Persian Gulf, were conducted using a combination of biological, sedimentological and echo‐sounding data. The survey area covered approximately 233 km2 in a depth range of 5–25 m, and the data were acquired from a single beam echo sounder, grab, video and still photography. Sediment and macrofauna samples were collected by grab at 76 stations and subjected to classification and ordination analyses. Two acoustic classes were identified differentiating along the near/offshore axis. Sediment texture was dominated by fine grain sizes, with five distinct sub‐sediment types. In total, 214 macrobenthic taxa were identified, of which polychaetes accounted for 60%. Other dominant groups included young sponges, nematodes, malacostracan crustacean, bivalves, ostracods and ophiuroids. Underwater videos and still photos integrated the macrofaunal and sedimentary data and revealed a range of biogenic sedimentary features such as burrows and tubes. The biological data identified six main biological assemblages showing an inshore/offshore pattern. The macrobenthic abundance did not demonstrate a significant difference with depth, although polychaetes were positively correlated with depth. The highest abundance and species richness were observed at median depths. Species distribution and diversity did not show any correlation with sediment type. A preliminary habitat mapping of the south coast of the Qeshm Island Geopark has been carried out, integrating acoustic, sediment and biological data.
Candida‐Agglutinationstiter bei ausgewählten Krankheitsgrappen:* Candida Agglutination Titres in Selected Groups of Diseases
Authors: Hübner Ursula , Heidenbluth Ingeburg , Heerdegen Edith
Published: January 2012

Zusammenfassung: Die Candida‐Agglutinationstiter von 431 Patienten, davon 378 mit Dermatosen, 40 mit Tumoren und ITS‐Patienten und 13 Leukosekranken, wurden unter Berücksichtigung der Sproßpilzbesiedlung der Haut, des Magen‐Darm‐Kanales oder mehrerer Organe ausgewertet. Die Häufigkeitsverteilungen der Titer der Patienten mit und ohne Pilznachweis ließen zwei deutlich unterscheidbare Kollektive erkennen. Hohe Werte wuden vorwiegend bei Besiedlung mehrerer Organsysteme gefunden. Diese traten bevozugt in den Gruppen der Kranken mit Tumoren, unter Intensivpflege, mit immunsuppressiver Dauertherapie und mit Diabetes mellitus auf. Eine absolute Trennung zwischen pathologiscben und Normal‐Titern ist nicht möglich. Der Wert 1:256 wird als kritischer Punkt angesehen.

Summary: Candida agglutination titres of 431 patients‐378 with skin diseases, 40 with neoplasms or under intensive therapeutical care and 13 with leukemia‐were analysed with regard to yeast colonization of the skin, the gastro‐intestinal tract or several other organs. Distribution of antibody titres in the two groups of patients with and without demonstration of fungi showed two distinct collectives. High levels were found predominantly in connection with colonization of several organs. This was mainly the case in patients with neoplasms, those under intensive care or long‐term immunosuppressive therapy or in patients with diabetes mellitus. An unequivocal distinction between pathological and normal titres is impossible. A titer of 1:256, however, seems to mark the critical point.
Das Vorkommen von Präzipitinen gegen Antigene aus toxigenen Pilzen in Seren von Kranken mit hämatologischen Affektionen: Incidence of Precipitins against Antigenes from Toxicogenic Fungi in Sera of Hematologic Patients
Authors: Baran E. , Walów B. , Nowicka J.
Published: January 2012

Zusammenfassung:Seren von 183 Kranken (Myelosis leucaemica acuta 82, Myelosis leucaemica chronica 28, Lymphadenosis leucaemica chronica 16, Lymphoma malignum 39, Aplasia medullae ossium et granulocyto penia 18) und 26 Kontrollpersonen wurden untersucht auf das Vorkommen von Präzipitinen gegen Antigene aus 22 Pilzarten (Aspergillus, Penicillium, Mucor, Rhizopus, Fusarium, Cladosporium, Stemphylium, Scopulariopsis, Syncephalastrum, Chaetomium, Candida, Geotrichum, rhodotorula). Bei neoplastischen Krankheiten konnten sehr häfig Immunreaktionen, besonders auf Antigene aus Aspergillus, Mucor und Rhizopusarten nachgewiesen werden. Bei der Ätiopathogenese von Blutkrankheiten wird die Rolle von Kontakten mit toxigenen Pilzen betont.

Summary:Sera from 183 hematologic patients (myelosis leucaemica acuta 83, myelosis leucaemica chronica 28, lymphadenosis leucaemica chronica 16, lymphoma malignum 39, aplasia medullae ossium et granulocytopenia 18) and 26 control persons were studied for the presence of precipitins against 22 fungal genera (Aspergillus, Penicilllum, Mucor, Rhizopus, Fusarium, Cladosporium, Stemphylium, Scopulariopsis, Syncephalastrum, Chaetomium, Candida, Geotrichum, Rhodotorula). In neoplastic diseases, frequent immune responses, aspecially against antigens from Aspergillus, Mucor and Rhizopus genera were demonstrated. In the etiopathology of blood diseases the role of contacts with toxicogenic fungi is stressed.
Vergleichende histologische und kulturelle Untersuchungen zum Vorkommen von Sproßipilzen in einem Obduktionsgut
Authors: Weber A. , Romig D.
Published: January 2012

Summary: Organ materials from 57 autopsies were investigated histologically and culturally in order to compare the occurrence of yeasts with both methods.

In materials of 12 autopsies (21,1 %) yeasts were demonstrated not only by culture but also by histology. From further 35 autopsies (61,4 %) yeasts were only found by isolation procedures. In most cases (56,9 %) Candida albicans was isolated, followed by Torulopsis glabrata (27,5 %) and Candida tropicalis (25,5%).

Yeasts were demonstrated not only by histological but also by cultural procedures especially in the respiratory system and in the oesophagus. In materials from patients who had died from inflammatory diseases, yeasts were detected in greater number than in other. The abundant number of yeasts demonstrated not only by cultural (93,3 %) but also by histological procedures (26,7) was remarkable in cases with cardiovascular Insufficieny.
Antimykotika‐Empfindlichkeit bei klinisch bedeutsamen Hefen und Schimmelpilzen im Hemmhoftest: Antimycotic Sensitivity of Clinically Important Yeasts and Moulds in the Agar Diffusion Method
Authors: Dermoumi Heide
Published: January 2012

Zusammenfassung: Gegenstand der vorliegenden Untersuchung ist das Resistenzverhalten von Hefen und Schimmelpilzen, die im Zeitraum von Mai 1978 bis Mai 1981 aus klinischem Untersuchungsmaterial isoliert wurden. Insgesamt wurden 2.024 Stämme im Diffusionstest untersucht. Resistente Stämme wurden bei den Polyenen Amphotericin B und Nystatin sehr selten gefunden (4 bzw. 6 Isolate). In 7,0 % der Fälle zeigte Candida albicans gegenäber 5‐Fluorcytosin keine Empfindlichkeit, während andere Arten bis zu zwei Dritteln auf dieses Mittel resistent reagierten. Gegenäber den Imidazolderivaten waren insgesamt 10,1% bei Clotrimazol und 13,4 % bei Miconazol als resistent eingestuft worden.

Summary: The susceptibility of yeasts and moulds in routine testing is demonstrated in this paper. A total of 2024 strains were examined by the diffusion technique during a period of 3 years (May 1978–May 1981). Test results showed good sensitivity against the polyenes amphoericin B and nystatin, only 4 rsp. 6 isolates were resistant against these anthnycotics. 7.0 per cent of Candida albicans strains were resistant against 5‐fluorocytosine, but the percentage of resistant isolates was usually higher in other species. 10.1 per cent of the isolates were classified as resistant to clotrimazol and 13.4 per cent were resistant to miconazol.
Vergleichsuntersuchungen zwischen Tolciclat und Miconazol bei oberflächlichen Dermatophytien und Pityriasis versicolor: Comparative Study of Therapeutic Effectiveness with Tolciclate and Miconazole in Superficial Dermatophytosis and in Pityriasis versicolor
Authors: Wiedey K. , Renovanz H.‐D. , Maier‐Lenz H.
Published: January 2012

Zusammenfassung: In der vorliegenden Untersuchung wurden oberflächliche Dermatophytien und Pityriasis versicolor an insgesamt 60 auswertbaren Patienten in einem intraindividuellen doppelblinden Halbseitenvergleich mit Toliclat und Miconazol behandelt. Im wesentlichen war der Behandlungserfolg für beide Substanzen nach einer dreiwöchigen Behandlungsphase erreicht. Die Therapie führte bei beiden Behandlungsgruppen zu einer hochsignifianten Abnahme aller ursprünglich erfaßten Krankheitssymptome. Die lokale Verträglichkeit war gut.

Summary: In the present investigation 60 interpretable patients were subjected to a comparative study of therapeutic effectiveness with Tolciclate and Miconazole in superficial dermatophytosis and pityriasis versicolor. The technique used for evaluation was based on within‐patient, double‐blind hemicomparison. Therapeutic success was achieved with both substances after 3 weeks of treatment. Therapy resulted in highly significant decline of all symptoms registered before treatment. Topical tolerance was equally favorable for both substances.
Etude écologique de Torulopsis glabrata dans une population de mammifères sauvages captifs: Ecological Study of Torulopsis Glabrata in a Captive Population of Wild Mammals
Authors: Saëz H. , Straziella L. , Kurdi Kornelia
Published: January 2012

Résumé: Le Torulopsis glabrata a été recherché dans le tube digestif des mammifères morts en captivité au Parc zoologique de Paris. L'investigation s'étend sur 17 années (1963–1979); les sièges testés comprennent: la cavité buccale, I'intestin grêle, le gros intestin, le rectum et, uniquement chez les mort‐nés et les sujets âgés au plus de 10 jours, l'estomac

Parmi les 1212 animaux examinés, appartenant à 150 espèces, 30 porteurs, et 20 espèces, ont été déce1és. L'investigation a porté successivement: sur l'incidence de l'âge et du régime alimentaire; sur la répartition des porteurs dans l'année et sur leur fréquence en fonction de la famille et de l'espèce zoologiques; sur la distribution de T. glabrata le long du tube digestif; enfin sur l'environnement fongique de T. glabrata au niveau des flores digestives étagées et sur les modèles d'association constatés avec d'autres micromycètes.

Summary: An investigation on Torulopsis glabrata, in the digestive tract (oral cavity, small and large intestines, rectum and, only in still‐born and young subjects not older 10 days, the stomach) was conducted in mammals who died in captivity in the Paris Zoological Park, during a 17‐year period from 1963 to 1979.

From 1212 mammals examined, belonging to 150 species, 30 carriers, belonging to 20 species, were detected. In this ecological report, the following points are studied: incidence of age and diet; yearly distribution of carriers; carriage influence according to the zoological family and species; distribution of T. glabrata along the digestive tract; fungal environment of T. glabrata in relation to the digestive flora in different sections of the digestive tract, models of association with other micromycetes.
Etiology of Dermatophytosis in Eastern Nigeria: A 7 Year Study: Ätiologie der Dermatophytosen in Ost Nigeria: Eine Untersuchung über 7 Jahre
Authors: Egere J. U. , Gugnani H. C.
Published: January 2012

Summary: A total of 1030 specimens of scrapings, hair and nail clippings were examined for the presence of dermatophytes. Out of these, 351 specimens were found positive for dermatophytes. Trichophyton rubrum was the most frequently isolated species represented by 107 (30.2%) isolates, followed by T. soudanense‐79 (22.2%) isolates and T. mentagrophytes var. mentagrophytes‐60 (17.1%) isolates. Epidermophyton floccosum and Microsporum audouinii were represented by 23 (6.2%) and 18 (5.5%) isolates respectively. The rarity of zoophilic dermatophytes was conspicuous. All the isolates of T. rubrum were of the ‘African variety’. T. soudanense was frequently isolated from lesions on scalp as well as from lesions on other parts of the body. Infections due to M. audouinii and T. soudanense were predominant in children, whereas those due to T. rubrum, E. floccosum and T. mentagrophytes were predominant in adults.

Zusammenfassung: Insgesamt wurden 1.030 Haut‐, Haar‐ und Nagelproben auf Dennatophyten untersucht. 351 dieser Proben führen zum Nachweis von Dermatophyten. Trichophyton rubrum war bei weitem am häufigsten mit 107 (30,2%) Isolaten. Es folgte T. soudanense mit 79 (22,2%) und T. mentagrophytes var. mit 60 (17,1%) Isolierungen. Epidermophyton floccosum und Microsporum audouinii wurden 23 × (6,2%) bzw. 18 × (5,5 %) isoliert. Die Seltenheit der zoophilen Dermatophyten war auffällig. Alle isolierten T. rubrum‐Stämme gehörten der „afrikanischen Varietät” an. T. soudanense wurde vor allem von der Kopfhaut, aber auch von anderen Körperpartien isoliert. Infektionen durch M. audouinii und T. soudanense kamen vor allem bei Kindern vor, während die Infektionen durch T. rubrum, E. floccosum und T. mentagrophytes vorwiegend bei Erwachsenen auftraten.