bluuebunny/crossref_metadata_2025_split huggingface dataset:
Peach latent mosaic viroid: not so latent
Authors: FLORES RICARDO , DELGADO SONIA , RODIO MARÍA‐ELENA , AMBRÓS SILVIA , HERNÁNDEZ CARMEN , SERIO FRANCESCO DI 
Published: June 2006

SUMMARY Taxonomy:  Peach latent mosaic viroid (PLMVd) is the type species of the genus Pelamoviroid within the family Avsunviroidae of chloroplastic viroids with hammerhead ribozymes.Physical properties:  A small circular RNA of 336–351 nt (differences in size result from the absence or presence of certain insertions) adopting a branched conformation stabilized by a pseudoknot between two kissing loops. This particular conformation is most likely responsible for the insolubility of PLMVd in highly saline conditions (in which other viroids adopting a rod‐like conformation are soluble). Both polarity strands are able to form hammerhead structures and to self‐cleave during replication as predicted by these ribozymes.Biological properties:  Although most infections occur without conspicuous symptoms, certain PLMVd isolates induce leaf mosaics, blotches and in the most extreme cases albinism (peach calico, PC), flower streaking, delays in foliation, flowering and ripening, deformations and decolorations of fruits, which usually present cracked sutures and enlarged roundish stones, bud necrosis, stem pitting and premature ageing of the trees, which also adopt a characteristic growing pattern (open habit). The molecular determinant for PC has been mapped at a 12–14‐nt insertion that folds into a hairpin capped by a U‐rich loop present only in certain variants. PLMVd is horizontally transmitted by the propagation of infected buds and to a lesser extent by pruning tools and aphids, but not by pollen; the viroid is not vertically transmitted through seed.Interesting features:  This provides a suitable system for studying how a minimal non‐protein‐coding catalytic RNA replicates (subverting a DNA‐dependent RNA polymerase to transcribe an RNA template), moves, interferes with the metabolism of its host (inciting specific symptoms and a defensive RNA silencing response) and evolves following a quasi‐species model characterized by a complex spectrum of variants.
Sex ratio and maturity indicate the local dispersal and mortality of adult stoneflies
Authors: PETERSEN I. , MASTERS Z. , ORMEROD S. J. , HILDREW A. G. 
Published: June 2006

Summary1. Despite a recent upsurge in interest, there remains remarkably little information about the dispersal and survival of the adults of most stream‐dwelling insects, although this is a basic requirement for understanding their long‐term population dynamics.2. Using Malaise traps for a whole annual flight period, we captured adult stoneflies (Leuctra nigra) along transects perpendicular to three upland Welsh streams. We assessed spatial and temporal patterns in sex ratio to infer local dispersal and, using maturity as an age marker, estimated the mortality of adult females.3. Nearly all adult stoneflies (99%) were taken in the period 26 April–23 July, and the onset of the male and female flight periods was the same. Most males (90%) had been caught by late June. Females were classified as immature (without ripe eggs) or mature, and 90% of immature females had been caught by mid‐late June (depending on catchment). As immature females declined in the catch, mature females increased, 10% having been caught by late‐May to early June and 90% by early to mid‐July. The median catches of immature and mature females were separated by 32 days in all three catchments.4. There was a female bias in the sex ratio overall, which increased as time passed and was attributable partially to the greater longevity of females. Late in the flight period, however, female bias was also greater near the stream channel implying a return of mature females (but not males) from the riparian vegetation, presumably to oviposit.5. The number of mature females was less than the number of immatures in two of the three channels. Over all three catchments, the overall mortality of females over the 32 days taken to mature was estimated at 29%, equivalent to an exponential daily rate of 1.1% day−1. The apparently negative mortality rate in one catchment (i.e. more matures than immatures being caught) could be due to an influx of adult females from elsewhere along the channel to oviposit.6. Natural markers of age and population structure, such as sex ratio and female maturity, thus enabled us to detect a return of females to the stream to oviposit, after prior limited dispersal into the riparian zone, and to infer longitudinal movements in search of suitable sites. We were also able to estimate mortality in the field. Such natural markers seem to have been underexploited in the study of adult aquatic insects.
Placental Expression of Glycophosphatidylinositol (GPI)‐anchored Proteins in Paroxysmal Nocturnal Haemoglobinuria
Authors: Kristoffersen E. K. , Haram K. O. , Edvardsen B. , Ernst P. , Bjørge L. 
Published: June 2006

AbstractParoxysmal nocturnal haemoglobinuria (PNH) is a clonal stem cell disorder in which a defect of glycophosphatidylinositol (GPI)‐anchored proteins leads to higher morbidity and mortality because of intravascular haemolysis, haemoglobinuria, pancytopenia and an increased frequency of thrombotic events. We report here the clinical features of a pregnant woman with PNH and present an immunhistochemical analysis of complement regulators, leukocyte activation markers and placental alkaline phosphatase (PALP) on syncytiotrophoblasts and inflammatory cells in her placenta. Placental tissue from normal deliveries served as controls. The patient had severe PNH with haemolysis, thrombosis episodes and signs of bone marrow failure. Placental syncytiotrophoblasts and villous cells of fetal origin in both normal placentas and the placenta from the PNH patient expressed PALP and the complement regulators CD46, CD55 and CD59. Additionally, CD11b‐positive leukocytes of presumed maternal origin were negative for CD15 in the PNH placenta, while they stained positive within the villous space and in normal placentas. These findings show that fetally derived cells in the PNH placenta expressed GPI‐linked molecules that are known to be of importance for a successful pregnancy outcome.
Retrograde suppression of GABAergic currents in a subset of SCN neurons
Authors: Gompf Heinrich S. , Irwin Robert P. , Allen Charles N. 
Published: June 2006

AbstractMany postsynaptic neurons release a retrograde transmitter that modulates presynaptic neurotransmitter release. In the suprachiasmatic nucleus (SCN), retrograde signaling is suggested by the presence of dendritic dense‐core vesicles. Whole‐cell voltage‐clamp recordings were made from rat SCN neurons to determine whether a retrograde messenger could modulate the activity of afferent γ‐aminobutyric acid (GABA)ergic inputs. The frequency and amplitude of spontaneous GABAergic currents was significantly reduced in a subpopulation of SCN neurons (eight out of 13) following a postsynaptic depolarization. Similarly, a postsynaptic depolarization significantly reduced the amplitude of evoked GABAergic currents during both day and night recordings. A postsynaptic depolarizing pulse eliminated paired‐pulse inhibition of GABAergic currents consistent with a presynaptic mechanism. Muscimol‐activated currents were not altered by postsynaptic depolarization, demonstrating that the activity of GABAA receptors was not altered. Depolarization‐induced inhibition of the GABAergic currents was not observed when a Ca2+ chelator was included in the microelectrode. Postsynaptic depolarization significantly increased the Ca2+ concentration in both the soma and dendrites. The dendritic Ca2+ levels increased faster, to a higher concentration and decayed faster than in the soma. The depolarization‐induced inhibition of the evoked GABAergic current was blocked by the G‐protein uncoupling agent N‐ethylmaleimide, suggesting that the retrograde messenger acts on a pertussis toxin‐sensitive G‐protein‐coupled receptor. Because the majority of SCN neurons receive GABAergic input from neighboring cells, these results describe a retrograde signaling mechanism by which SCN neurons can modulate GABAergic synaptic input.
Sleep‐active neurons in the preoptic area project to the hypothalamic paraventricular nucleus and perifornical lateral hypothalamus
Authors: Uschakov Aaron , Gong Hui , McGinty Dennis , Szymusiak Ronald 
Published: June 2006

AbstractThe lamina terminalis consists of the organum vasculosum of the lamina terminalis (OVLT), median preoptic nucleus (MnPO) and subfornical organ. The MnPO and ventrolateral preoptic area (vlPOA) are known to contain high densities of neurons that are sleep active. The prevalence of sleep‐active neurons in the OVLT and subfornical organ is unknown. The vlPOA and subdivisions of the lamina terminalis project to hypothalamic regions involved in the control of behavioral, electrographic or autonomic arousal, including the lateral hypothalamic area (LHA) and paraventricular nucleus (PVN). The extent to which projection neurons are active during sleep is unknown. We quantified c‐Fos protein immunoreactivity (IR) in the lamina terminalis and vlPOA in sleeping and awake rats that received injections of retrograde tracer into either the LHA or PVN. Fos IR was also examined in lamina terminalis neurons following tracer injections into the vlPOA. Significantly more projection neurons from the MnPO, OVLT and vlPOA to the LHA were Fos‐immunoreactive in sleeping vs. awake animals. Waking Fos IR was more prevalent in lamina terminalis neurons projecting to the PVN although a subset of MnPO projection neurons in sleeping rats was Fos‐immunoreactive. Almost 50% of vlPOA‐PVN projection neurons expressed Fos IR during sleep, compared with 3% during waking. Significantly more neurons in the OVLT and MnPO projecting to the vlPOA were Fos‐immunoreactive in sleeping vs. awake rats. Inhibition of LHA and PVN neurons arising from OVLT, MnPO and vlPOA neurons may contribute to suppression of behavioral, electroencephalographic and sympathetic nervous system activation during sleep.
TheDrosophila cacts2mutation reduces presynaptic Ca2+entry and defines an important element in Cav2.1 channel inactivation
Authors: Macleod G. T. , Chen L. , Karunanithi S. , Peloquin J. B. , Atwood H. L. , McRory J. E. , Zamponi G. W. , Charlton M. P. 
Published: June 2006

AbstractVoltage‐gated Ca2+channels in nerve terminals open in response to action potentials and admit Ca2+, the trigger for neurotransmitter release. Thecacophonygene encodes the primary presynaptic voltage‐gated Ca2+channel inDrosophilamotor‐nerve terminals. Thecacts2mutant allele ofcacophonyis associated with paralysis and reduced neurotransmission at non‐permissive temperatures but the basis for the neurotransmission deficit has not been established. Thecacts2mutation occurs in the cytoplasmic carboxyl tail of the α1‐subunit, not within the pore‐forming trans‐membrane domains, making it difficult to predict the mutation's impact. We applied a Ca2+‐imaging technique at motor‐nerve terminals of mutant larvae to test the hypothesis that the neurotransmission deficit is a result of impaired Ca2+entry. Presynaptic Ca2+signals evoked by single and multiple action potentials showed a temperature‐dependent reduction. The amplitude of the reduction was sufficient to account for the neurotransmission deficit, indicating that the site of thecacts2mutation plays a role in Ca2+channel activity. As the mutation occurs in a motif conserved in mammalian high‐voltage‐activated Ca2+channels, we used a heterologous expression system to probe the effect of this mutation on channel function. The mutation was introduced into rat Cav2.1 channels expressed in human embryonic kidney cells. Patch‐clamp analysis of mutant channels at the physiological temperature of 37 °C showed much faster inactivation rates than for wild‐type channels, demonstrating that the integrity of this motif is critical for normal Cav2.1 channel inactivation.
Troglitazone, a peroxisome proliferator‐activated receptor‐γ agonist, decreases tau phosphorylation in CHOtau4R cells
Authors: D'Abramo Cristina , Ricciarelli Roberta , Pronzato Maria A. , Davies Peter 
Published: June 2006

AbstractPeroxisome proliferator‐activated receptor‐γ (PPARγ), a member of the nuclear receptor superfamily, is activated by several compounds including the thiazolidinediones. In addition to being a target for diabetes, PPARγ activation state has recently been shown to modulate β‐amyloid peptide (Aβ) production in cellular models relevant to Alzheimer's disease. Here, we report the effect of troglitazone, a thiazolidinedione, in cells expressing 4‐repeat tau. A 24 h treatment with troglitazone significantly reduced phosphorylation of tau at Ser202 and Ser396/404, residues of early and later stages of neurofibrillary tangle accumulation in Alzheimer's disease and other neurodegenerative disorders. Under the same experimental conditions the level of tau did not change. In our cellular model, troglitazone appeared to enhance 3′‐phosphoinositide‐dependent protein kinase 1 (PDK1) nuclear translocation, resulting in a decrease in cytosolic phosphorylated 70 kDa ribosomal protein kinase (p70S6) and phosphorylated mammalian target of rapamycin (mTor). Furthermore, PPARγ transcriptional activity did not appear to be responsible for decreased phosphorylation of tau. Thus, we believe that the thiazolidinedione regulates tau phosphorylation through a PPARγ‐dependent/independent mechanism involving an Akt/glycogen synthase kinase‐3(GSK‐3β)‐independent signalling cascade: PDK1/p70S6K/mTor.
The transcription factor ΔFosB is recruited by inflammatory pain
Authors: Luis‐Delgado Oliva Erendira , Barrot Michel , Rodeau Jean‐Luc , Ulery Paula G. , Freund‐Mercier Marie‐José , Lasbennes François 
Published: June 2006

AbstractΔFosB, a stable splice variant of FosB, has been proposed to mediate persistent brain adaptation in response to several chronic perturbations, but it has not yet been considered in the context of sustained pain. Inflammatory pain induces neuronal plasticity that can result in persistent alteration of nociceptive pathways. This neuronal plasticity can partly result from changes in gene expression controlled by transcription factors. In the present study, we analyse the capacity of carrageenan‐mediated inflammation to induce ΔFosB in the spinal cord. We found that hind‐paw inflammation increases FosB‐like immunoreactivity in the superficial layers of rat lumbar spinal cord for at least 7 days. This induction parallels mechanical hyperalgesia and is maximal in the dorsal horn of segment L4 of the spinal cord which corresponds to the primary nociceptive afferent regions from the hind paw. We identified this FosB‐like signal as ΔFosB by comparing data obtained with antibodies raised against either an epitope present in both FosB and ΔFosB, or the FosB C‐terminal region that is deleted in ΔFosB. The week‐lasting changes in ΔFosB highlight the interest in this protein as a molecular marker of sustained pain, and suggest a role of this transcription factor in pain‐related plasticity within the spinal cord.
Lipid mobilization from human abdominal, subcutaneous adipose tissue is independent of sex during steady‐state exercise
Authors: Bülow Jens , Gjeraa Kirsten , Enevoldsen Lotte H. , Simonsen Lene 
Published: June 2006

SummaryThe aim of the study was to elucidate whether there are sex differences of significant biological importance in the human abdominal, subcutaneous adipose tissue lipid metabolism when studied by Fick's Principle during rest and exercise in steady‐state conditions. The net mobilization of fatty acids and glycerol from the abdominal, subcutaneous adipose tissue was measured by arterio‐venous catheterizations and simultaneous measurements of adipose tissue blood flow with the local Xe‐clearance technique in 16 healthy, young normal weight men and women during rest, during 1 h of exercise at moderate intensity, and for another 60 min during post‐exercise recovery. The results show that there are not significant sex differences with respect to the steady‐state fatty acid and glycerol mobilizations neither during resting condition nor during exercise.
Fibrohistiocytic skin tumors
Authors: Hügel Heino 
Published: June 2006

SummaryThe fibrohistiocytic tumors of the skin are a heterogeneous group of dermal/subcutaneous mesenchymal neoplasms which show fibroblastic, myofibroblastic and histiocytic (macrophage‐like) differentiation, often one beside the other in the same tumor. “Fibrohistiocytic” means in this context the morphologic similarity of the cells with fibroblasts and histiocytes.The WHO classification of 2005 includes the following entities as fibrohistiocytic tumors of the skin: Benign: 1. Fibrous histiocytoma (FH)/(synonymous: Dermatofibroma. Variants of FH: 1a. cellular fibrous histiocytoma, 1b. atypical (pseudosarcomatous) fibrous histiocytoma, 1c. aneurysmatic fibrous histiocytoma, 1d. epithelioid fibrous histiocytoma; 2. dermatomyofibroma; 3. (juvenile) xanthogranuloma. Intermediate: 4. plexiform fibrohistiocytic tumor; 5. dermatofibrosarcoma protuberans; 6. atypical Fibroxanthoma. Malignant: 7. malignant fibrous histiocytoma.All these entities are reviewed in this paper with particular attention devoted to differential diagnostic considerations.
Ecological situation and management of Bothriochloa ischaemum grasslands in China
Authors: Zhang Jin‐Tun , Zhang Gui‐Lian 
Published: June 2006

Abstract Bothriochloa ischaemum grasslands cover a large area of central China. A total of 81 grassland quadrats of 2 m × 2 m were established randomly in nine counties of central China. Data for species composition, abundance, coverage and height, plus several environmental variables were measured and recorded in each quadrat. Dry biomass and productivity for three associations within three counties were also determined. Species data of importance values were used in the two‐way indicator species analysis (TWINSPAN) and the detrended correspondence analysis (DCA) ordination. A total of 11 main grassland associations were distinguished by the TWINSPAN classification; all of them being secondary vegetation. Each association had its own characteristics in composition, structure, productivity and environment. The results of DCA show that the distribution of B. ischaemum grasslands and associated species are closely related to longitude, that is, related to a moisture gradient. Precipitation was one of the most important factors affecting the distribution of the studied grasslands. In addition, topographic factors, such as elevation, aspect, slope and soil types, were also correlated to grassland vegetation. The distribution of grassland associations was consistent to that of their dominant species. TWINSPAN and DCA revealed the same ecological gradients in this study. These grasslands are important for regional development of animal husbandry and economy, although their productivity is not very high. Effective protocols for the conservation and management of B. ischaemum grasslands are needed.
Browder's type strong convergence theorems for infinite families of nonexpansive mappings in Banach spaces
Authors: Suzuki Tomonari 
Published: June 2006

AbstractWe prove Browder's type strong convergence theorems for infinite families of nonexpansive mappings. One of our main results is the following: let "Equation missing" be a bounded closed convex subset of a uniformly smooth Banach space "Equation missing". Let "Equation missing" be an infinite family of commuting nonexpansive mappings on "Equation missing". Let "Equation missing" and "Equation missing" be sequences in "Equation missing" satisfying "Equation missing" for "Equation missing". Fix "Equation missing" and define a sequence "Equation missing" in "Equation missing" by "Equation missing" for "Equation missing". Then "Equation missing" converges strongly to "Equation missing", where "Equation missing" is the unique sunny nonexpansive retraction from "Equation missing" onto "Equation missing".
Sensitivity and specificity of a quantitative point of care D-dimer assay using heparinized whole blood, in patients with clinically suspected deep vein thrombosis
Authors: Korte Wolfgang , Schwab Michael , Zerback Rainer , Huisman Menno , Dempfle Carl-Erik ,   on behalf of the CARDIM study group
Published: June 2006

SummaryD-dimer assays are efficient in the exclusion diagnostics of deep vein thrombosis (DVT) in patients without severe concomitant diseases. We have determined diagnostic sensitivity and specificity of a new point-of-care rapid assay for quantitative determination of D-dimer in heparinized whole blood in outpatients with suspected DVT. In 19 participating centers, 637 patients were included in the study, of which 77 were excluded, the majority because of inadequate documentation of analytical quality control measures. DVT was diagnosed in 223 of the remaining 560 patients by duplex ultrasound examination. The POC D-dimer assay showed a high sensitivity of 96.9% for the diagnosis of DVT and a high specificity of 60.8% at a pre-specified cutoff of 0.5 µg/ml. For Tina-quant D-dimer, sensitivity was slightly lower at 94.9%, with a specificity of 64.8%.The VIDAS D-dimer assay showed a sensitivity of 98.2%, but specificity was 40.7%. The area under the curve (AUC ± standard error, 95% confidence interval) was 0.879 ± 0.019 (0.845–0.909) for POC D-dimer, 0.908 ± 0.016 (0.877–0.934) for Tina-quant D-dimer, and 0.895± 0.018 (0.862–0.922) forVIDAS D-dimer. Differences were not statistically significant. The new whole blood POC D-dimer assay isa reliable tool for exclusion of DVT in symptomatic outpatients, displaying a comparable diagnostic performance as VIDAS D-dimer and Tina-quant D-dimer assays.Roche CARDIAC and TINA-QUANT are tradenames of Roche.
Early in vivo anticoagulation inhibits the angiogenic response following hindlimb ischemia in a rodent model
Authors: De Paula Erich , Nascimento Mariane , Ramos Celso , Ozelo Margareth , Machado Tânia , Guillaumon Ana , Annichino-Bizzacchi Joyce , Arruda Valder 
Published: June 2006

SummaryEmerging findings have demonstrated the critical role of blood clotting factors in the formation and stabilization of embryonic blood vessels. Whether a similar role is true during post-natal angiogenesis remains to be determined. Here we sought to determine whether the suppression of thrombin generation with anticoagulant drugs at doses routinely used for therapeutic purposes would affect the angiogenesis pattern following hindlimb ischemia in rats. Animals were treated with r- hirudin or enoxaparin within six hours post induction of hindlimb ischemia, whereas two other groups received oral anticoagulation warfarin beginning at day 3 post-ischemia or saline (as control). The revascularization anatomical and functional responses were evaluated 30 days following tissue ischemia. Chronic administration of the drugs resulted in stable anticoagulation in all animals throughout the experiment. Animals that received drugs with fast anticoagulation effects (i.e. r-hirudin and enoxaparin) presented a significant decrease in capillary density and capillary-to-myocyte ratio compared to control animals. These effects were not associated with changes in relative perfusion of the hindlimb at steady state. These anti-angiogenic effects occur in a time-dependent manner, since delayed inhibition of coagulation (> 72 hours) presents no adverse effect on the angiogenic response. We conclude that the use of anticoagulant drugs immediately after tissue ischemia induction hampers in vivo angiogenic response in a rodent hindlimb ischemia model.
Oxidized States of Methoxy-sexithiophene Derivative with Ferrocenyl Groups
Authors: Sato Masa-aki , Fukui Kazuhiko 
Published: June 2006

Abstract
Methoxy-sexithiophene derivative with two ferrocenyl terminal groups was prepared as a model compound for molecular wires. The oxidation process and the oxidized states of the model compound were investigated by cyclic voltammetry, coulometry, and electronic absorption spectroscopy. The first oxidation occurs in a ferrocene moiety, terminal, and the resultant oxidized species strongly interacts not only with the methoxy-sexithiophene moiety, but also with the other ferrocene.