bluuebunny/crossref_metadata_2025_split huggingface dataset:
Identification and functional characterization of EhClC‐A, an Entamoeba histolytica ClC chloride channel located at plasma membrane
Authors: Salas‐Casas Andrés , Ponce‐Balderas Arturo , García‐Pérez Rosa María , Cortés‐Reynosa Pedro , Gamba Gerardo , Orozco Esther , Rodríguez Mario A. 
Published: January 2006

SummaryClC chloride channels perform a wide variety of physiological functions and they had been characterized in animals, yeast, plants and bacteria but not in protozoa. By blast search we found in Entamoeba histolytica, the protozoan responsible for human amoebiasis, two genes (Ehclc‐A and Ehclc‐B) encoding for putative polypeptides with 25–30% identity to ClC chloride channels of several organisms. Reverse transcription polymerase chain reaction (RT‐PCR) experiments showed that both genes are transcribed in trophozoites. Phylogenetic analysis revealed that EhClC‐A and EhClC‐B polypeptides belong to the eukaryotic branch of plasma membrane ClCs. Specific antibodies against EhClC‐A confirmed that it is located at the trophozoite plasma membrane. Xenopus laevis oocytes microinjected with Ehclc‐A cRNA elicited anion currents not detected in oocytes microinjected with water. Induced currents were inwardly rectifying and had a permeability sequence of Cl– > Br– > I– > F– >> NO3–. The chloride channel blocker 4‐acetamido‐4′isothiocyanostilbene‐2, 2′‐disulphonic acid (SITS) strongly inhibited the oocytes anion currents and trophozoites growth. Experiments at diverse pHs suggested that EhClC‐A is not a Cl–/H+ exchanger, but it is an ion channel that could be involved in pH regulation. EhClC‐A may also participate in cell volume regulation. As far as we know, EhClC‐A is the first chloride channel characterized in protozoa.
GPS measurements of ground deformation induced by water level variations into a granitic aquifer (French Brittany)
Authors: Moreau Frédérique , Dauteuil Olivier , Bour Olivier , Gavrilenko Pierre 
Published: January 2006

AbstractWe used two semi‐permanent GPS receivers with differential configuration to measure the hydrological subsidence of an aquifer used for water supply, located on a fractured granitic area. The time series of the vertical deformation measurements of the ground surface show a variation of 2 cm between winter and summer. We investigate the relationship between this vertical deformation and hydraulic head variations. We show that this kind of GPS survey allows characterizing part of the hydrological properties of such a heterogeneous aquifer. This is thus a new approach of time continuous monitoring of the deformation related to hydrogeological processes.
Saxo‐Thuringia in the Variscan belt from a geodynamic point of view
Authors: Sommer Max , Katzung Gerhard 
Published: January 2006

AbstractSaxo‐Thuringia is a suture bounded part of the Variscan belt in central Europe and represents a fragment of the Armorica microplate. Structural investigations and a critical review of other geologic data allow the reconstruction of its geodynamic history. Two south‐dipping subduction zones, corresponding to the Rheno‐Herzynian and the Tepla sutures, delimited Saxo‐Thuringia before the Variscan orogeny. As a result of the continental collision between Avalonia to the north and a further fragment of Armorica to the south, both outer realms of Saxo‐Thuringia record high‐grade metamorphism and a subsequent uplift between 340 and 310 Ma. Contemporaneously, the low‐grade metamorphic internal zone of Saxo‐Thuringia records thrust contraction of the late Pre‐Cambrian basement and the formation of a fold belt in the overlaying Palaeozoic deposits. Two pre‐Variscan tectonic imprints are distinguishable: (1) the consolidation of late Pre‐Cambrian basement in the Cadomian–Avalonian belt and (2) a Cambrian and early Ordovician rift setting related to the opening of the Rheic ocean and the fragmentation and separation of Armorica.
Crustal thickening and lateral flow during compression of hot lithospheres, with particular reference to Precambrian times
Authors: Cagnard Florence , Durrieu Nicolas , Gapais Denis , Brun Jean‐Pierre , Ehlers Carl 
Published: January 2006

AbstractMany ancient deformation belts, especially of Archean and Palaeoproterozoic age, show large areas marked by primary flat‐lying fabrics associated with rather monotonous metamorphic conditions of HTLP type and affected by steep transpressive zones involving vertical stretch. These features do not support strain localization along large‐scale thrusts and (or) extensional detachments, as common in modern orogens. Instead, they are consistent with hot and weak lithospheres where gravity‐driven horizontal flow may compete with distributed thickening from early stages of collisional processes. Relevant deformation features are reviewed and highlighted by lithosphere‐scale analogue models involving low‐viscosity lower crust and sub‐Moho mantle. Both nature and models argue that compression of such lithospheres may induce combined distributed thickening and lateral channel flow of the ductile crust accommodated by transpressive zones.
Uniform Permian40Ar/39Ar detrital mica ages in the eastern Qaidam Basin (NW China): where is the source?
Authors: Rieser Andrea B. , Liu Yongjiang , Genser Johann , Neubauer Franz , Handler Robert , Ge Xiao‐Hong 
Published: January 2006

AbstractNew single‐grain40Ar/39Ar detrital white‐mica ages from the Lulehe section at the eastern Qaidam Basin yield uniform Permian ages between 250 ± 3 and 279 ± 3 Ma throughout the whole Cenozoic sequence. This is inconsistent with the present hinterland, which is composed of early Palaeozoic metamorphic units with subordinate early Palaeozoic and few Permian granites. The new data indicate that Permian tectonic units are likely more widespread at the north‐eastern margin of the Tibetan plateau as known at present, particularly within the Qilian Mountains. The preferred explanation is that the Qaidam block represents a rigid indenter, which indented during late Tertiary times into early Palaeozoic orogenic units. This is consistent with recent findings of a NW‐trending sinistral Permian ductile shear zone and a dextral, NW‐trending Tertiary fault system close to the north‐eastern margin of the Qaidam Basin.
Reconstructing asymmetrical reproductive character displacement in a periodical cicada contact zone
Authors: Cooley John R. , Marshall David C. , Hill Kathy B. R. , Simon Chris 
Published: January 2006

Abstract
Selection against costly reproductive interactions can lead to reproductive character displacement (RCD). We use information from patterns of displacement and inferences about predisplacement character states to investigate causes of RCD in periodical cicadas. The 13-year periodical cicada Magicicada neotredecim exhibits RCD and strong reproductive isolation in sympatry with a closely related 13-year species, Magicicada tredecim. Displacement is asymmetrical, because no corresponding pattern of character displacement exists within M. tredecim. Results from playback and hybridization experiments strongly suggest that sexual interactions between members of these species were possible at initial contact. Given these patterns, we evaluate potential sources of selection for displacement. One possible source is ‘acoustical interference’, or mate-location inefficiencies caused by the presence of heterospecifics. Acoustical interference combined with the species-specificity of song pitch and preference appears to predict the observed asymmetrical pattern of RCD in Magicicada. However, acoustical interference does not appear to be a complete explanation for displacement in Magicicada, because our experiments suggest a significant potential for direct sexual interactions between these species before displacement. Another possible source of selection for displacement is hybrid failure. We evaluate the attractiveness of inferred hybrid mating signals, and we examine the viability of hybrid eggs. Neither of these shows strong evidence of hybrid inferiority. We conclude by presenting a model of hybrid failure related to life cycle differences in Magicicada.
Modulation of sexual signalling by immune challenged male mealworm beetles (Tenebrio molitor, L.): evidence for terminal investment and dishonesty
Authors: Sadd B. , Holman L. , Armitage H. , Lock F. , Marland R. , Siva-jothy M. T. 
Published: January 2006

Abstract
Organisms partition resources into life-history traits in order to maximise fitness over their expected lifespan. For the males of many species fitness is determined by qualitative and quantitative aspects of costly sexual signals: The notion that epigamic traits are costly forms the cornerstone of those theories that propose parasites drive sexual selection. Consequently studies examining this notion assume sexual signalling is honest (i.e. driven by cost) when they seek to identify correlations or causal links between male immune function and attractiveness. We demonstrate that immune challenged males of the mealworm beetle, Tenebrio molitor, increased their investment in epigamic pheromone signals: these males became significantly more attractive to females whilst increasing the activity of a key immune effector system. In other words males increase terminal reproductive effort (invest in attractiveness) in response to a survival threat (immune insult). Consequently the signal preferred by the female is dishonest when considering the male's condition.
A new route to the evolution of cooperation
Authors: Santos F. C. , Pacheco J. M. 
Published: January 2006

Abstract
The Prisoner's Dilemma (PD) constitutes a widely used metaphor to investigate problems related to the evolution of cooperation. Whenever evolution takes place in well-mixed populations engaged in single rounds of the PD, cooperators cannot resist invasion by defectors, a feature, which is somewhat alleviated whenever populations are spatially distributed. In both cases the populations are characterized by a homogeneous pattern of connectivity, in which every individual is equivalent, sharing the same number of neighbours. Recently, compelling evidence has been accumulated on the strong heterogeneous nature of the network of contacts between individuals in populations. Here we describe the networks of contacts in terms of graphs and show that heterogeneity provides a new mechanism for cooperation to survive. Specifically, we show that cooperators are capable of exploring the heterogeneity of the population structure to become evolutionary competitive. As a result, cooperation becomes the dominating trait in scale-free networks of contacts in which the few highly connected individuals are directly inter-connected, in this way contributing to self-sustain cooperation.
Distortion of symmetrical introgression in a hybrid zone: evidence for locus-specific selection and uni-directional range expansion
Authors: Johannesen J. , Johannesen B. , Griebeler E. M. , Baran I. , Tunç M. R. , Kiefer A. , Veith M. 
Published: January 2006

Abstract
The fate of species integrity upon natural hybridization depends on the interaction between selection and dispersal. The relative significance of these processes may be studied in the initial phase of contact before selection and gene flow reach equilibrium. Here we study a hybrid zone of two salamander species, Lyciasalamandra antalyana and Lyciasalamandra billae, at the initial phase of hybridization. We quantify the degree and mode of introgression using nuclear and mtDNA markers. The hybrid zone can be characterized as an abrupt transition zone, the central hybrid zone being only c. 400 m, but introgressed genes were traced up to 3 km. Introgression was traced in both sexes but gene flow may be slightly male-biased. Indirect evidence suggests that hybrid males are less viable than females. Introgression occurred at two levels: (1) locus-specific selection led to different allelic introgression patterns independent of species, while (2) asymmetrical species-level introgression occurred predominately from L. antalyana to L. billae due to range expansion of the former. This indicates that foreign genes can be incorporated into novel genomic environments, which in turn may contribute to the great diversity of morphological variants in Lyciasalamandra.
Gis-based niche models reveal unifying climatic mechanisms that maintain the location of avian hybrid zones in a North American suture zone
Authors: Swenson N. G. 
Published: January 2006

AbstractThe existence of suture zones in North America has recently been verified, yet the environmental factors responsible for the maintenance of their structure and position have remained undetermined. The Great Plains suture zone in the US is perhaps the most significant and broadly studied in North America. Numerous avian hybrid zones that cluster in this region have been extensively studied over the last half-century. A primary result of this work is that exogenous factors present in this region have promoted and maintained avian species divergence. Yet, to date the variables most important in the generation and the clustered positioning of these hybrid zones in relation to one another have not been determined. The present study aims to advance our understanding of this North American suture zone by using niche modelling to quantify which environmental variables are most important in its formation and maintenance. Through the generation of fundamental niches for four hybrids and their parental species, similarities linking the hybrid zones were uncovered. The results show that temperature holds this suture zone in position and also suggest that temperature played a primary role in promoting niche differentiation among these sister species pairs during Pleistocene glacial cycles.
Lawsonia intracellularisProliferative Enteropathy in a Filly
Authors: Wuersch K. , Huessy D. , Koch C. , Oevermann A. 
Published: January 2006

SummaryProliferative enteropathy (PE) caused by the obligate intracellular bacteriumLawsonia intracellularisis a disease of high economic impact in swine worldwide. In most other species the disease occurs as a sporadic infection. This paper reports a PE caused byL. intracellularisin a 9‐month‐old Pura Raza Española filly with a history of profuse diarrhoea. Pathological lesions consisted of a severe proliferative enteritis associated with argyrophilic bacteria in the apical cytoplasm of proliferating crypt epithelium. Characteristic PCR products confirmed the presumptive diagnosis ofL. intracellularisinfection. To our knowledge this is the first report of PE in a horse in Europe caused byL. intracellularis.
Pharmacokinetics of a Lidocaine Patch 5% in Dogs
Authors: Weiland L. , Croubels S. , Baert K. , Polis I. , De Backer P. , Gasthuys F. 
Published: January 2006

SummaryLidocaine is increasingly used in transdermal drug delivery systems for different pain conditions in human medicine whereby several pharmacokinetic studies have demonstrated minimal systemic absorption in men. In the present study, the pharmacokinetics of a lidocaine patch 5% was studied in six dogs. In the first experiment, one single lidocaine patch was applied for 12 h to the lateral side of the thorax after removing the hair either by clipping or by the application of a depilatory agent, according to a two‐way crossover design. No potential adverse effects induced by the patches were observed in either group. In dogs with clipped hair, a mean peak plasma lidocaine concentration of 62.94 ng/ml was obtained after 10.67 h. In the depilatory group, a mean peak plasma concentration of 103.55 ng/ml was reached after 9.27 h. Significant differences in the AUC0 → ∞, Cmax, ka and T1/2a were noticed between the two groups. No significant differences were found for the elimination parameters and for Tmax. In the second experiment, the patches were applied for 60 h to the clipped skin in order to study the absorption kinetics after a prolonged application period. There, the mean peak lidocaine plasma concentration was 45.18 ng/ml achieved after 24 h and a final concentration of 29.37 ng/ml was obtained at 60 h. In conclusion, all dogs tolerated the transdermal lidocaine patch well. The results of this study suggest that there is an overall minimal absorption from the lidocaine patch. However, the application of a depilatory agent leads to a more rapid and increased absorption of lidocaine.
Echium vulgare and Senecio vulgaris Poisoning in Fighting Bulls
Authors: Moyano M. R. , García A. , Rueda A. , Molina A. M. , Mendez A. , Infante F. 
Published: January 2006

SummaryAn unusual case of poisoning by simultaneous ingestion of Echium vulgare L. and Senecio vulgaris L. in a herd of Spanish fighting bulls is described. Ten animals died from a herd of 700 in an area located in Sierra Norte, Seville (Constantina) in Spain. The interest of this case lies both in the breed affected (this is the first report on fighting bulls) and the lack of information about bovine poisoning by these plants in Spain. Animal samples were obtained from October to March. All the dead animals were 1 year old and had grazed at the farm. The diagnosis was made by determining the plant species and studying its distribution in the pastureland, and also by performing blood analysis of the sick animals in addition to an anatomopathological study of the carcasses. Tuberculosis, brucellosis, salmonellosis, IBR/BVD and also the presence of aflatoxins in the forage were all ruled out.
Fasting‐induced Changes in Ovulation Rate, Plasma Leptin, Gonadotropins, GH, IGF‐I and Insulin Concentrations During Oestrus in Ewes
Authors: Kosior‐Korzecka U. , Bobowiec R. , Lipecka Cz. 
Published: January 2006

SummaryThe aim of this experiment was to study the changes in the hormonal status and ovulation rate (OR) evoked by starvation during the follicular phase of the oestrous cycle in ewes. To achieve this goal, 12 female crossbreed sheep were synchronized and then half of them were fasted from the 12th to the 16th day of the oestrous cycle. On the 16th day, analysis of hormones and insulin‐like growth factor‐I (IGF‐I) were performed in 10‐min intervals. Then, on the 6th day of the following oestrous cycle, the OR in all ewes was determined by laparoscopy. Fasting reduced significantly (P < 0.05) the OR in ewes (1.25 ± 0.50) in comparison with control (1.75 ± 0.50). The drop in the OR was coincident with a significant (P < 0.001) decrease in the plasma concentration and pulse amplitude of leptin (0.29 ± 0.08 ng/ml versus control 0.53 ± 0.14 ng/ml), the plasma level of luteinizing hormone (LH) (0.19 ± 0.06 IU/l versus 0.25 ± 0.09 IU/l in control; P < 0.05) and the mean frequency of LH pulses (2.0/h versus 2.5/h in control). Fasting resulted also in a significant (P < 0.05) decrease in the plasma concentration and pulse amplitude of follicle stimulating hormone (FSH) in comparison with the control. Simultaneously, a significant (P < 0.001) drop in the IGF‐I concentration in the fasted ewes (4.78 ± 0.91 ng/ml) was found in comparison with control (7.63 ± 1.85 ng/ml). Also the level of insulin were significantly (P < 0.001) lower in the fasted (178.99 ± 39.08 pm/l respectively) than in the control sheep (302.66 ± 49.01 pm/l respectively). Meanwhile, a double increase in the growth hormone (GH) pulses frequency and an augmentation in its plasma concentrations as a result of starvation was found. The obtained results shows that the acute fasting exerts an inhibitory effect on the ovulation rate in ewes coincident with suppression in leptin, FSH and LH secretion and changes in signalization mediated by GH.
Seroprevalence of Ornithobacterium rhinotracheale Infection in Broiler and Broiler Breeder Chickens in West Azerbaijan Province, Iran
Authors: Allymehr M. 
Published: January 2006

Summary Ornithobacterium rhinotracheale is a pleomorphic Gram‐negative rod shaped bacterium of the rRNA superfamily V that is associated with respiratory disease in poultry. This study was conducted to determine the seroprevalence of O. rhinotracheale infection in broiler and broiler breeder chickens in West Azerbaijan (Urmia lake region) by using a commercial enzyme‐linked immunosorbent assay. In this study, 463 serum samples were obtained from 50 broiler flocks and 472 blood sera from 42 broiler breeder flocks. Results showed that 41 broiler flocks (82%) and 39 broiler breeder flocks (92.8%) were positive. Ornithobacterium rhinotracheale antibodies were detected in 205 (44.2%) of the 463 broiler serum samples. Of the 472 blood sera examined from broiler breeder, 340 (72%) were positive. The results of this study indicated that the prevalence of O. rhinotracheale antibodies is high in the broiler and broiler breeder flocks in West Azerbaijan.
Design of tomato fruits with reduced allergenicity by dsRNAi‐mediated inhibition of ns‐LTP (Lyc e 3) expression
Authors: Le Lien Quynh , Lorenz Yvonne , Scheurer Stephan , Fötisch Kay , Enrique Ernesto , Bartra Joan , Biemelt Sophia , Vieths Stefan , Sonnewald Uwe 
Published: January 2006

SummaryPlant genetic engineering has the potential to introduce new allergenic proteins into foods but, at the same time, it can be used to remove established allergens. Here, we report the molecular characterization of Lyc e 3, a new tomato (Lycopersicon esculentum) allergen, and the efficient down‐regulation of its expression in transgenic tomato plants. Following the identification of an immunoglobulin E (IgE)‐binding 9‐kDa polypeptide in tomato peel, designated Lyc e 3, its partial amino acid sequence was determined by N‐terminal protein sequencing. Sequence comparison revealed that Lyc e 3 encodes a nonspecific lipid transfer protein (ns‐LTP). In plants, ns‐LTPs are encoded by large gene families which differ in primary amino acid sequence, expression and proposed cellular function. To identify Lyc e 3 encoding complementary DNAs (cDNAs), public tomato expressed sequence tag (EST) databases were screened for ns‐LTP sequences. Following this strategy, two cDNAs, LTPG1 and LTPG2, with high homology to the N‐terminal sequence of Lyc e 3, were identified. Ectopic expression of LTPG1 and LTPG2 in Escherichia coli, followed by immunoblotting, verified their IgE reactivity. Subsequently, transgenic tomato plants constitutively expressing LTPG1‐ or LTPG2‐specific double‐stranded RNA interference (dsRNAi) constructs were created and tested for the suppression of Lyc e 3 accumulation. Efficient silencing of Lyc e 3 was documented by Northern and Western blotting. In both cases, Lyc e 3 accumulation was decreased to levels below the detection limit (less than 0.5% of the wild‐type protein). The allergenic potential of Lyc e 3‐deficient tomato fruits was tested by measuring histamine release from sensitized human basophils stimulated with transgenic and parental lines. These assays revealed a strong (10‐ to 100‐fold) decrease in histamine release of human basophils challenged with transgenic fruit extracts when compared with control extracts. These results demonstrate the feasibility of creating low allergenic tomato fruits by means of dsRNAi inhibition.