bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dermoscopy of Kaposi's sarcoma: Areas exhibiting the multicoloured ‘rainbow pattern’
Authors: Hu S C‐S , Ke C‐L K , Lee C‐H , Wu C‐S , Chen G‐S , Cheng S‐T 
Published: April 2009

AbstractBackground  Kaposi's sarcoma is a vascular tumour characterized by a proliferation of spindle cells and endothelial cells to form closely arranged slit‐like vascular spaces. Currently, the definitive diagnosis of Kaposi's sarcoma relies on histology. The dermoscopic features of Kaposi's sarcoma are not clearly defined in the scientific literature.Objectives  We seek to evaluate the dermoscopic features of Kaposi's sarcoma and compare them with other vascular tumours.Methods  One hundred forty‐one lesions from seven patients with histologically proven Kaposi's sarcoma were evaluated using polarized light dermoscopy for the presence of various dermoscopic features. Twenty patients with other vascular tumours were also examined.Results  Dermoscopic examination revealed bluish‐reddish coloration (84% of lesions), multicoloured areas showing various colours of the rainbow spectrum (36%), scaly surface (29%), and small brown globules (15%). The ‘rainbow pattern’ was found in six out of seven patients with Kaposi's sarcoma and was not observed in other vascular tumours. In addition, there was an absence of dermoscopic features specific for other vascular and non‐vascular skin tumours, such as well‐defined lacunae or structured vascular pattern, in most of the Kaposi's sarcoma lesions.Conclusions  The most frequent dermoscopic patterns in Kaposi's sarcoma were found to be bluish‐reddish coloration, the ‘rainbow pattern’, and scaly surface. The rainbow pattern is a dermoscopic feature which has not been previously described. We propose that dermoscopy, as an adjunct to clinical examination, may enhance accuracy in the preoperative diagnosis of Kaposi's sarcoma.
Why cordylid lizards are black at the south‐western tip of Africa
Authors: Janse van Rensburg D. A. , Mouton P. le F. N. , Van Niekerk A. 
Published: April 2009

AbstractThere is a high incidence of melanism among the cordylid lizards of Africa and it was suggested that melanism has a thermoregulatory function in these species. One prediction of the thermal melanism hypothesis would be that melanistic cordylid species would be restricted to cool environments. The aim of our study was to determine the climatic conditions with which melanistic cordylids are currently associated. Distributional data for the eight melanistic cordylid taxa occurring at the south‐western tip of Africa were obtained from the CapeNature State of Biodiversity database. Using GIS and principal component analyses, the climatic variables best describing the geographical distribution of melanistic cordylids were investigated. We found that several melanistic cordylid populations show a distinct association with a high incidence of fog and cloud cover, underscoring the thermal melanism hypothesis. Several other populations, however, do not show such an association. We conclude that some species, such as Pseudocordylus capensis, have a morphology that provides them with great flexibility in habitat use, allowing them to overcome the constraints of melanism in warm environments. The available information suggests that melanism in cordylids evolved during the Miocene in response to the development of the cold Benguela Current along the west coast of Africa. We also conclude that viviparity, a sit‐and‐wait foraging strategy and a rock‐dwelling lifestyle would have preadapted cordylids for survival in cool conditions brought about by the development of the cold Benguela Current. These conditions would have been unfavourable for oviparous, active‐foraging lizards. The co‐occurrence of melanistic lizards and melanistic molluscs at the Landdroskop locality casts some doubt on improved heating rates as the only explanation for melanism in cordylids, because molluscs are not heliothermic baskers.
Do plant parts compete for resources? An evolutionary viewpoint
Authors: Sadras Victor O. , Denison R. Ford 
Published: April 2009

SummarySimultaneously growing sinks are thought to compete for plant resources. Negative correlations, for example between grain number and stem mass in cereals, indeed resemble competition; but is the notion of intra‐plant competition evolutionarily justified? Here we review intra‐plant competition in light of two aspects of evolutionary biology: (a) major transitions that led to the reorganization of evolutionary individuals (e.g. isolated DNA molecules and independent cells) into new units of adaptation (e.g. chromosomes and multicellular organisms) with associated constraints to intra‐individual conflict; and (b) genomic conflicts within individual plants with implications for resource allocation. Against this background, we look at apparent competition among genetically identical plant parts, and conclude that plants might use competition‐like mechanisms to allocate resources, but only to the extent that these proximate mechanisms enhance overall plant fitness. In dealing with apparent competition among genetically different plant structures, we emphasize developing seeds attached to the same maternal plant, and the determination of yield components in annual crops. We propose that competition‐like mechanisms among genetically different plant parts have been strongly shaped by the evolution of genomic conflict between parent and offspring, between female and male parents, and among siblings. By defining the number and potential size of grain simultaneously and before fertilization, a strong maternal control of resource allocation is exerted that favours uniform offspring size and partially counteracts genomic conflict.
Cell entry strategy of clostridial neurotoxins
Authors: Binz Thomas , Rummel Andreas 
Published: April 2009

AbstractTetanus neurotoxin and botulinum neurotoxins are the causative agents of tetanus and botulism. They block the release of neurotransmitters from synaptic vesicles in susceptible animals and man and act in nanogram quantities because of their ability to specifically attack motoneurons. They developed an ingenious strategy to enter neurons. This involves a concentration step via complex polysialo gangliosides at the plasma membrane and the uptake and ride in recycling synaptic vesicles initiated by binding to a specific protein receptor. Finally, the neurotoxins shut down the synaptic vesicle cycle, which they had misused before to enter their target cells, via specific cleavage of protein core components of the cellular membrane fusion machinery. The uptake of four out of seven known botulinum neurotoxins into synaptic vesicles has been demonstrated to rely on binding to intravesicular segments of the synaptic vesicle proteins synaptotagmin or synaptic vesicle protein 2. This review summarizes the present knowledge about the cell receptor molecules and the mode of toxin‐receptor interaction that enables the toxins’ sophisticated access to their site of action.
The surface‐exposed chaperone, Hsp60, is an agonist of the microglial TREM2 receptor
Authors: Stefano Luisa , Racchetti Gabriella , Bianco Fabio , Passini Nadia , Gupta Radhey S. , Bordignon Paola Panina , Meldolesi Jacopo 
Published: April 2009

AbstractTriggering receptor expressed in myeloid (TREM) cells 2, a receptor expressed by myeloid cells, osteoclasts and microglia, is known to play a protective role in bones and brain. Mutations of the receptor (or of its coupling protein, DAP12) sustain in fact a genetic disease affecting the two organs, the polycystic lipomembraneous osteodysplasia with sclerosing leukoencephalopathy (PLOSL or Nasu‐Hakola disease). So far, specific agonist(s) of TREM2 have not been identified and its (their) transduction mechanisms are largely unknown. Heat shock protein 60 (Hsp60) is a mitochondrial chaperone that can also be harboured at the cell surface. By using constructs including the extracellular domain of TREM2 and the Fc domain of IgGs we have identified Hsp60 as the only TREM2‐binding protein exposed at the surface of neuroblastoma N2A cells and astrocytes, and lacking in U373 astrocytoma. Treatment with Hsp60 was found to stimulate the best known TREM2‐dependent process, phagocytosis, however, only in the microglial N9 cells rich in the receptor. Upon TREM2 down‐regulation, the Hsp60‐induced stimulation of N9 phagocytosis was greatly attenuated. Hsp60 is also released by many cell types, segregated within exosomes or shedding vesicles which might then undergo dissolution. However, the affinity of its binding (Kd = 3.8 μM) might be too low for the soluble chaperone released from the vesicles to the extracellular space to induce a significant activation of TREM2. It might in contrast be appropriate for the binding of TREM2 to Hsp60 exposed at the surface of cells closely interacting with microglia. The ensuing stimulation of phagocytosis could play protective effects on the brain.
Pharmacological evidences for DFK167‐sensitive presenilin‐independent γ‐secretase‐like activity
Authors: Sevalle Jean , Ayral Erwan , Hernandez Jean‐François , Martinez Jean , Checler Frédéric 
Published: April 2009

AbstractAmyloid‐β (Aβ) peptides production is thought to be a key event in the neurodegenerative process ultimately leading to Alzheimer’s disease (AD) pathology. A bulk of studies concur to propose that the C‐terminal moiety of Aβ is released from its precursor β‐amyloid precursor protein by a high molecular weight enzymatic complex referred to as γ‐secretase, that is composed of at least, nicastrin (NCT), Aph‐1, Pen‐2, and presenilins (PS) 1 or 2. They are thought to harbor the γ‐secretase catalytic activity. However, several lines of evidence suggest that additional γ‐secretase‐like activities could potentially contribute to Aβ production. By means of a quenched fluorimetric substrate (JMV2660) mimicking the β‐amyloid precursor protein sequence targeted by γ‐secretase, we first show that as expected, this probe allows monitoring of an activity detectable in several cell systems including the neuronal cell line telencephalon specific murine neurons (TSM1). This activity is reduced by DFK167, N‐[N‐(3,5‐difluorophenacetyl)‐L‐alanyl]‐S‐phenylglycine t‐butyl ester (DAPT), and LY68458, three inhibitors known to functionally interact with PS. Interestingly, JMV2660 but not the unrelated peptide JMV2692, inhibits Aβ production in an in vitroγ‐secretase assay as expected from a putative substrate competitor. This activity is enhanced by PS1 and PS2 mutations known to be responsible for familial forms of AD and reduced by aspartyl mutations inactivating PS or in cells devoid of PS or NCT. However, we clearly establish that residual JMV2660‐hydrolysing activity could be recovered in PS‐ and NCT‐deficient fibroblasts and that this activity remained inhibited by DFK167. Overall, our study describes the presence of a proteolytic activity displaying γ‐secretase‐like properties but independent of PS and still blocked by DFK167, suggesting that the PS‐dependent complex could not be the unique γ‐secretase activity responsible for Aβ production and delineates PS‐independent γ‐secretase activity as a potential additional therapeutic target to fight AD pathology.
Distinct role of growth hormone on epilepsy progression in a model of temporal lobe epilepsy
Authors: Kato Keiko , Suzuki Masakazu , Kanno Hiroki , Sekino Shinji , Kusakabe Ken , Okada Toshiya , Mori Tetsuji , Yoshida Kazuyuki , Hirabayashi Yoshio 
Published: April 2009

AbstractTemporal lobe epilepsy is a common form of pharmacoresistant epilepsy, in which epileptogenic foci propagate to other regions of the brain from the area of the initial insult. The present study focused on epileptogenesis, that is, the development of the first foci inducing seizures in amygdala‐kindled mice, a model of temporal lobe epilepsy, to find the molecular process promoting the formation of epileptogenic networks. The expression of growth hormone (GH) was up‐regulated along neural circuits during the epileptogenesis, while there was no difference in the pituitary gland. The up‐regulation was associated with increased phosphorylation/activation of signal transducer and activator of transcription 5 and expression of the Serum Response Element‐regulated genes, FBJ osteosarcoma oncogene, early growth response 1, and Jun‐B oncogene, suggesting that expression of GH leads to GH signaling in the hippocampus and cortex. Furthermore, the administration of the hormone into the hippocampus markedly enhanced the progression of kindling. The administration of an inhibitor of its secretion into the hippocampus elicited a delay in the progression. Our results demonstrate directly that regulation via growth hormone has a robust impact in epileptogenesis.
Neuroprotection by estrogen in the brain: the mitochondrial compartment as presumed therapeutic target
Authors: Arnold Susanne , Beyer Cordian 
Published: April 2009

AbstractNeuroprotection by estrogen in the CNS is well‐documented and comprises the intricate regulation of cell–cell communication between neurons and supportive non‐neuronal glial cells. It is assumed that these interactions are essential for cell survival under pathological and toxic conditions by regulating the allocation of trophic molecules, e.g., growth factors, controlling relevant intracellular anti‐apoptotic and death cascades, and attenuating inflammatory processes. Malfunction and disturbance of mitochondria are doubtlessly associated with brain cell degeneration during neurotoxic and neurodegenerative processes. Estrogen has been documented as protective agent in the brain by stimulating growth factor supply and cell‐intrinsic pro‐/anti‐apoptotic signaling pathways. In recent years, an additional estrogen‐dependent safe‐guarding strategy comes into the focus of neuronal protection. The mitochondrial compartment appears to be regulated by estrogen at the level of ATP and reactive oxygen species production as well as under a structural‐functional viewpoint. In the present article, we would like to highlight recent data which demonstrate that sex steroids can directly and indirectly interfere with mitochondrial properties via non‐nuclear, presumably mitochondria‐intrinsic and nuclear signaling mechanisms. This enables mitochondria to cope with pathological processes and provide stabile local energy homeostasis and an anti‐apoptotic base setting in the brain which, in turn, is a prerequisite for neuronal survival.
Stored red blood cell supernatant facilitates thrombin generation
Authors: Sweeney Joseph , Kouttab Nicola , Kurtis Jonathan 
Published: April 2009

BACKGROUND: Observational studies have reported that patients transfused with red blood cells (RBCs) have a worse clinical outcome than untransfused patients and that storage age of RBCs at the time of transfusion may be an independent predictor of this adverse clinical outcome.STUDY DESIGN AND METHODS: Eight RBC concentrates in additive solution were studied over an 8‐week storage period. The RBC supernatant was ultracentrifuged to concentrate microvesicles (RCMVs). RCMVs were studied by flow cytometry to identify phosphatidylserine (PS)‐expressing RCMVs and in a thromboelastograph (TEG) using a modified assay to detect a thrombin facilitation effect.RESULTS: For all products, the percentage of RCMVs that exhibited PS expression on Day 1 was 50 ± 13%, which increased with storage, and on Day 31 was 90 ± 4%. After 31 days, four of the eight products showed a thrombin facilitation effect as evidenced by a shortening of the TEG reaction (R) time of 1.3 ± 1.1 minutes, which persisted to Day 41. Data are the mean ± 1 SD. This TEG R shortening effect was neutralized by annexin V. No such effect was observed on, or before, Day 21.CONCLUSIONS: Some stored RBCs release RCMVs, which express PS and are capable of facilitating thrombin generation in vitro. This provides a possible mechanism by which stored RBCs could promote adverse thrombotic or inflammatory effects.
Egg‐laying tactic inPhyllomorpha laciniatain the presence of parasitoids
Authors: Carrasco David , Kaitala Arja 
Published: April 2009

AbstractFemale insects are expected to choose oviposition sites that have the best conditions for offspring development and survival. Natural enemies, such as predators and parasitoids, may have a strong influence on the selection of oviposition substrates by phytophagous insects. The golden egg bug,Phyllomorpha laciniata(Villers) (Heteroptera: Coreidae) has an unusual reproductive strategy. Females mainly use conspecifics, both males and other females, as egg‐laying substrates, but occasionally they oviposit on plants as well. Survival of the eggs is higher when eggs are carried by conspecifics than when they are laid on plants, due to predation and parasitism. We investigated egg‐laying behavior in the forced presence of the egg parasitoidGryon bolivari(Giard) (Hymenoptera: Scelionidae). Specifically, we studied whether females provide egg protection by avoiding oviposition under the risk of egg parasitization. We expected a lower oviposition rate under parasitoid presence, and the eggs, if any, to be placed preferably on conspecifics and not on plants, thus ensuring higher survival of the progeny. The results show thatP. laciniata’s egg‐laying rate was lower when they were enclosed with parasitoids than when parasitoids were absent, especially when plants were the only substrate to oviposit on. Moreover, females showed strong preference for laying eggs on conspecifics rather than on plants. Egg‐laying inP. laciniataappears to be not only influenced by the availability of conspecifics, but also by the presence of egg parasitoids. This indicates that females may be able to detectG. bolivariand avoid oviposition when parasitoids are present. We discuss the possibility of conspecifics as enemy‐free space.
Spontaneous recovery of an intensively used grassland after cessation of fertilizing
Authors: Královec Josef , Pocová Lenka , Jonášová Magda , Macek Petr , Prach Karel 
Published: April 2009

AbstractQuestions: (1) Does a fertilized grassland recover in terms of species composition and species richness after stopping the treatment? (2) Which species contributed most to the changes? (3) Is it realistic to rely upon spontaneous recovery in this and similar cases?Location: A large grassland, located in the western part of the Czech Republic in central Europe, latitude 49° 59′, longitude 12° 45′, altitude 750 m a.s.l.Methods: Experimental plots of 2.5 m × 6.0 m were established in the central part of the grassland in 1968 using a randomized block design with the following variants: unfertilized controls, 80, 160, 240 and 320 kg ha−1 of nitrogen, in four or eight (320 kg) replicates. The fertilization regime was stopped in 1989. Phytosociological relevés of 2 m × 4 m in size were made in 1990, 1994, 1996, 1997, 1999, 2003 and 2006. The data were processed by multivariate ordination methods (DCA, CCA). Differences in the number of species per plot were tested by repeated measures anova and Tukey's HSD test.Results: All plots, including controls, exhibited a distinct trajectory through time, reflecting the rates of fertilizer used and generally changing in the same direction. Both time and nutrients significantly influenced the vegetation pattern. Treatments differed significantly in species richness, especially at the beginning of the observation. Differences in later years were less pronounced, thus a convergence between the treatments was evident.Conclusions: During the 16 years after fertilization ceased, the number of species substantially increased not only in the fertilized plots but also in the controls. Species typical of semi‐natural grasslands predominantly contributed to the increase. Spontaneous recovery after cessation of fertilizing was relatively efficient, but the fertilized plots were small in size and thus rather easily colonized from outside. For interpretation and extrapolation of results from small experimental plots, it is necessary to consider changes in the broader surroundings.
Assessing the impact of plant invasions on soil seed bank communities: use of univariate and multivariate statistical approaches
Authors: Gioria Margherita , Osborne Bruce 
Published: April 2009

AbstractQuestions: Are soil seed banks affected by invasions of alien plants? How can we rigorously assess alterations in seed bank communities associated with invasive species and account for the high spatial variability of seed bank data? How do multivariate approaches compare with more traditional approaches based on analysis of variance?Location: Three riparian sites, Ireland.Methods: A protocol based on a combination of multivariate techniques was used to characterize soil seed bank communities associated with the herbaceous invasive species Heracleum mantegazzianum in May and October. Permutational multivariate analysis of variance (PERMANOVA) was used to test the effects of the factors “invasion”, “site”, “plot” and “depth” on the soil seed bank, while multivariate analysis of dispersion (PERMDISP) provided a measure of the variability of seed bank data at different spatial scales. Similarity percentages analysis (SIMPER) was used to identify the species that contributed most to the differences between invaded and uninvaded communities. A comparison between the results of PERMANOVA and ANOVA analyses was also made.Results: The composition of seed bank communities invaded by H. mantegazzianum differed significantly from that of uninvaded seed banks. Invaded seed banks were less diverse and had reduced abundance, and were dominated by only a few species, such as Urtica dioica and Juncus effusus. Such patterns were recorded at each of three depth categories, indicating that invasive plants can affect both the transient and the more persistent component of the soil seed bank. Seed bank variability was significantly higher within uninvaded areas, supporting the notion that invasions tend to lead to more homogeneous communities.Conclusion: The analytical protocol used in this study was effective in quantifying the effect of plant invasions, at different spatial scales, providing a statistically robust analysis of alterations in soil seed bank communities. Compared to ANOVA, this protocol provided more biological information and was more appropriate for analysis of the data. This approach is therefore recommended in soil seed bank and invasion ecological studies.