bluuebunny/crossref_metadata_2025_split huggingface dataset:
Genetic evidence reveals temporal change in hybridization patterns in a wild baboon population
Authors: TUNG J. , CHARPENTIER M. J. E. , GARFIELD D. A. , ALTMANN J. , ALBERTS S. C. 
Published: March 2008

AbstractThe process and consequences of hybridization are of interest to evolutionary biologists because of the importance of hybridization in understanding reproductive isolation, speciation, and the influence of introgression on population genetic structure. Recent studies of hybridization have been enhanced by the advent of sensitive, genetic marker‐based techniques for inferring the degree of admixture occurring within individuals. Here we present a genetic marker‐based analysis of hybridization in a large‐bodied, long‐lived mammal over multiple generations. We analysed patterns of hybridization between yellow baboons (Papio cynocephalus) and anubis baboons (Papio anubis) in a well‐studied natural population in Amboseli National Park, Kenya, using genetic samples from 450 individuals born over the last 36 years. We assigned genetic hybrid scores based on genotypes at 14 microsatellite loci using the clustering algorithm implemented in structure 2.0, and assessed the robustness of these scores by comparison to pedigree information and through simulation. The genetic hybrid scores showed generally good agreement with previous morphological assessments of hybridity, but suggest that genetic methods may be more sensitive for identification of low levels of hybridity. The results of our analysis indicate that the proportion of hybrids in the Amboseli population has grown over time, but that the average proportion of anubis ancestry within hybrids is gradually decreasing. We argue that these patterns are probably a result of both selective and nonselective processes, including differences in the timing of life‐history events for hybrid males relative to yellow baboon males, and stochasticity in long‐distance dispersal from the source anubis population into Amboseli.
New interpretations of fine‐scale spatial genetic structure
Authors: DICK CHRISTOPHER W. 
Published: March 2008

AbstractRecent methodological advances permit refined inferences of evolutionary processes from the fine‐scale spatial genetic structure of plant populations. In this issue of Molecular Ecology, Born et al. (2008) exploit the full power of these methods by examining effects of ancient and recent landscape histories in an African rainforest tree species. The authors first detected admixture of distinct gene pools that may have formed in Pleistocene forest refuges. Then, comparing across six study populations in Gabon, the authors found similar patterns of fine‐scale spatial genetic structure despite natural and anthropogenic variation in population density. The latter results suggest that enhanced gene dispersal may compensate for low population densities in fragmented landscapes.
The Bassian Isthmus and the major ocean currents of southeast Australia influence the phylogeography and population structure of a southern Australian intertidal barnacle Catomerus polymerus (Darwin)
Authors: YORK KATHERINE L. , BLACKET MARK J. , APPLETON BELINDA R. 
Published: March 2008

AbstractSouthern Australia is currently divided into three marine biogeographical provinces based on faunal distributions and physical parameters. These regions indicate eastern and western distributions, with an overlap occurring in the Bass Strait in Victoria. However, studies indicate that the boundaries of these provinces vary depending on the species being examined, and in particular on the mode of development employed by that species, be they direct developers or planktonic larvae dispersers. Mitochondrial DNA sequence analysis of the surf barnacle Catomerus polymerus in southern Australia revealed an east–west phylogeographical split involving two highly divergent clades (cytochrome oxidase I 3.5 ± 0.76%, control region 6.7 ± 0.65%), with almost no geographical overlap. Spatial genetic structure was not detected within either clade, indicative of a relatively long‐lived planktonic larval phase. Five microsatellite loci indicated that C. polymerus populations exhibit relatively high levels of genetic divergence, and fall into four subregions: eastern Australia, central Victoria, western Victoria and Tasmania, and South Australia. FST values between eastern Australia (from the eastern mitochondrial DNA clade) and the remaining three subregions ranged from 0.038 to 0.159, with other analyses indicating isolation by distance between the subregions of western mitochondrial origin. We suggest that the east–west division is indicative of allopatric divergence resulting from the emergence of the Bassian land‐bridge during glacial maxima, preventing gene flow between these two lineages. Subsequently, contemporary ecological conditions, namely the East Australian, Leeuwin, and Zeehan currents and the geographical disjunctions at the Coorong and Ninety Mile Beach are most likely responsible for the four subregions indicated by the microsatellite data.
Towards natural polyploid model organisms
Authors: BUGGS RICHARD J. A. 
Published: March 2008

AbstractPopulations of natural allopolyploids with available and well‐developed genomic resources are currently hard to come by. These are needed because whole genome duplication and hybridization — both combined in allopolyploids — are significant processes in evolution, especially the evolution of plants. The new characterization of a naturally occurring allopolyploid in the genus Mimulus by Sweigart et al. in this issue of Molecular Ecology is therefore to be welcomed. Mimulus is rapidly emerging as a model system for evolutionary functional genomics. Sequences of the whole genome and 200 000 expressed sequence tags of diploid M. guttatus, a putative parent of the polyploid described in this issue, will soon be available. These will facilitate investigation of the fates of genes duplicated by whole genome duplication, and their effects on morphology, mating system and ecology in natural populations.
Pathozone dynamics of Meloidogyne incognita in the rhizosphere of tomato plants in the presence and absence of the nematophagous fungus, Pochonia chlamydosporia
Authors: Bailey D. J. , Biran G. L. , Kerry B. R. , Gilligan C. A. 
Published: March 2008

Pathozone dynamics were derived for approx. 50 Meloidogyne incognita juveniles infecting a single root of tomato under controlled conditions from a point source of inoculum and described using simple, non‐linear models. The pathozone decayed sigmoidally with distance, but increased over time as progressively more nematodes were able to infect the root. Despite the reported ability of M. incognita juveniles to travel up to 50 cm in some conditions, the maximum width of the pathozone for a single tomato root was estimated as 18·1 mm. It is conjectured that this was because of (i) diffusion from a point source of inoculum, (ii) a small infection court (a single root tip) and (iii) the limited life span of the nematode. A second experiment was used to assess the effect of the nematophagous fungus Pochonia chlamydosporia on the pathozone dynamics of the nematode. This fungus is known to produce nematicidal products in vitro, which may affect invasion of roots by the free‐living nematode. To examine the possibility of a change in the position of the site of infection, changes in the probability of gall formation along the root length were also examined. In the absence of P. chlamydosporia, the pathozone dynamics of M. incognita were very similar to those of the first experiment. It was shown that P. chlamydosporia did not significantly affect the pathozone dynamics of M. incognita nor the site of gall formation, which appear to have little importance for the role of the fungus as a biological control agent.
The Potential Role of Lung Epithelial Cells and β‐defensins in Experimental Latent Tuberculosis
Authors: Rivas‐Santiago B. , Contreras J. C. L. , Sada E. , Hernández‐Pando R. 
Published: March 2008

Abstract Mycobacterium tuberculosis is a facultative intracellular pathogen capable of producing both progressive disease and latent infection. Latent infection is clinically asymptomatic and is manifested only by a positive tuberculin test or a chest radiograph that shows scars or calcified nodules indicative of resolved primary tuberculosis infection. In this study, we used a well‐characterized model of latent tuberculosis infection in B6D2F1 mice to compare the production of β‐defensin‐3 by infected bronchial epithelial cells and macrophages. We demonstrated by immunolectronmicroscopy that M. tuberculosis can actually infect epithelial cells and induce significant higher production of β‐defensin‐3 associated to mycobacteria than infected macrophages. These results demonstrate that lung epithelium harbour mycobacteria during experimental chronic infection; being a possible reservoir of latent mycobacteria in vivo, β‐defensins might participate in bacilli killing or dormancy induction.
Expansion and Activation of NK Cell Populations in a Gammaherpesvirus Infection
Authors: Thomson R. C. , Petrik J. , Nash A. A. , Dutia B. M. 
Published: March 2008

AbstractNK cells are an important component of the innate immune response to many virus infections. In particular, they play a major role in control of alpha and beta herpesvirus infections in humans and mice and there is evidence for a protective role in Epstein–Barr virus infection. MHV‐68 has been widely used to study gammaherpesvirus pathogenesis and provides a tractable means of investigating the role of NK cells in gammaherpesvirus infections. We have shown that, following MHV‐68 infection of mice, the NK cell population is expanded and activated and capable of cytotoxic killing in vitro. However, depletion of NK cells prior to MHV‐68 infection did not affect viral loads in vivo. To investigate the possibility that MHV‐68 was downregulating NK cell activity in vivo and evading the NK cell response, we infected NK cell‐depleted mice with the related virus, MHV‐76, which lacks a 9.5 kb region of the genome known to be involved in modulating the host immune response. Infection of NK cell‐depleted mice with MHV‐76 did not result in increased viral loads indicating that genes within this region do not encode products which modulate NK cell activity.
Calcitization/dedolomitization of Jurassic dolostones (Lebanon): results from petrographic and sequential geochemical analyses
Authors: NADER FADI H. , SWENNEN RUDY , KEPPENS EDDY 
Published: March 2008

AbstractCalcitized Jurassic dolostones from central Mount Lebanon (Kesrouane Formation) are discussed utilizing petrographic, mineralogical and geochemical data. In particular, two sequential extraction methods for both major/trace elements and stable isotope analyses provide results that support and refine conventional bulk analyses data. The new data demonstrate that the major dedolomitization phase of the investigated Jurassic carbonates occurred as a result of the migration of karst‐related meteoric waters (characterized by soil‐derived carbon, and estimated δ18OV‐SMOW composition between −7·2‰ and −3·4‰) into previously dolomitized horizons within the limestone rock, during the final uplift and emergence of Mount Lebanon, after Palaeogene time. The study demonstrates that, in this case, the mechanisms of dedolomitization and their resulting fabrics are controlled primarily by the texture of the original dolomite rock. Pervasively dolomitized rocks, where the micritic matrix is entirely dolomitized, show calcitization mainly through dissolution/precipitation. By contrast, the rock textures that still include a considerable amount of limey micritic matrix – spared from dolomitization – are more prone to mole per mole and mimic replacement of the dolomite crystals by calcite.
Flow conditions of the 2004 Indian Ocean tsunami in Thailand, inferred from capping bedforms and sedimentary structures
Authors: Choowong Montri , Murakoshi Naomi , Hisada Ken‐ichiro , Charoentitirat Thasinee , Charusiri Punya , Phantuwongraj Sumet , Wongkok Prawpan , Choowong Alongkorn , Subsayjun Rittirong , Chutakositkanon Vichai , Jankaew Kruawan , Kanjanapayont Pitsanupong 
Published: March 2008

AbstractThe 2004 Indian Ocean tsunami deposited a sheet of sand with surficial bedforms at the Andaman coast of Thailand. Here we show the recognition of bedforms and the key internal sedimentary structures as criteria of the tsunami supercritical flow condition. The presence of well‐preserved capping bedforms implied a dominant tsunami inflow. Sets of internal sedimentary structures including parallel lamination, seaward and landward inclined‐laminations, and downstream dipping laminae indicated antidune structures that were generated by a supercritical flow current in a depositional stage during the inflow. A set of seaward dipping cross‐laminations containing sand with mud drape on the surface of one depositional layer are a unique indication of an outflow structure. A majority of deposits show normal grading, but in some areas, localized reverse grading was also observed. The recognition of these capping bedforms and determination of the internal sedimentary structures provides new key criteria to help derive a better understanding of tsunami flow conditions.
Add‐on omalizumab improves day‐to‐day symptoms in inadequately controlled severe persistent allergic asthma
Authors: Humbert M. , Berger W. , Rapatz G. , Turk F. 
Published: March 2008

Background:  Omalizumab is efficacious in the treatment of moderate‐to‐severe and severe persistent allergic (immunoglobulin E‐mediated) asthma, reducing exacerbations, emergency visits and improving quality of life (QoL). However, as exacerbations are relatively infrequent, assessment of efficacy on day‐to‐day symptoms is warranted.Aims:  To investigate the effect of add‐on omalizumab on day‐to‐day symptoms, and how they correlate with QoL in severe persistent asthma.Methods:  The correlation between asthma symptom scores and QoL [Asthma Quality of Life Questionnaire (AQLQ)] was assessed. Symptom‐free days (total symptom score = 0) and symptom‐controlled days (definition 1: total symptom score ≤1; and definition 2: morning peak expiratory flow ≥90% of baseline, daytime asthma score ≤1 and night‐time asthma score = 0) were compared between the omalizumab‐treated group, omalizumab responders and placebo.Results:  Four hundred and nineteen patients (omalizumab, n = 209; placebo, n = 210) were included in the efficacy analyses, and 61% (118/195) of patients with response data were classified as responders. Total symptom score strongly correlated with AQLQ overall and symptom scores and individual domains. AQLQ overall score correlated well with symptom scores. Responders had significantly more symptom‐free days than the omalizumab‐treated and placebo groups (45.8%, 37.2% and 22.6% respectively), and more symptom‐controlled days (definition 1: 56.1%, 47.9% and 35.3%, respectively, and definition 2: 50.8%, 43.9% and 28.0%, respectively).Conclusions:  In patients with inadequately controlled severe persistent asthma, day‐to‐day symptoms correlate well with QoL. Add‐on omalizumab significantly improves day‐to‐day symptoms compared with placebo. Further improvement in responders confirms the physician’s assessment as a response measure.
Song perception among incipient species as a mechanism for reproductive isolation
Authors: BRAMBILLA M. , JANNI O. , GUIDALI F. , SORACE A. 
Published: March 2008

AbstractMany functions in behavioural processes of small passerines are regulated via vocal messages. Song plays an important role in the development of reproductive barriers and thus playback experiments can often be used for investigating the potential for reproductive isolation through behavioural mechanisms. Moltoni’s warbler Sylvia (cantillans) moltonii is characterized by diagnostic vocalizations and a peculiar pattern of distribution, being parapatric and partly sympatric with the nominate Sylvia c. cantillans. With this work, we test whether these two closely related taxa react equally to their own song and to the song of the other taxon, shedding light on whether they perceive each other’s songs as coming from the same species. We carried out 184 playback experiments within the mainland range of the two forms. We judged the response of the bird on a scale of scores. Each taxon responded more strongly to playback when faced with the song of its own taxon. This held true when applied only to males or females. Additionally, birds tested for both songs showed a stronger response to the song of their own taxon. The distributional context (sympatry vs. allopatry) did not affect bird response. Results indicate that a certain degree of reproductive isolation between the two taxa (because of diverged mate recognition systems) already exists; consistently with genetic data and with the peculiar pattern of distribution; this suggests that the two taxa have reached species status.
A hybrid zone with coincident clines for autosomal and sex‐specific markers in theSorex araneusgroup
Authors: YANNIC G. , BASSET P. , HAUSSER J. 
Published: March 2008

AbstractIn hybrid zones, endogenous counter‐selection of hybrids is usually first expressed as reduced fertility or viability in hybrids of the heterogametic sex, a mechanism known as Haldane’s rule. This phenomenon often leads to a differential of gene flow between sex‐linked markers. Here, we address the possibility of a differential gene flow for Y chromosome, mtDNA and autosomal markers across the hybrid zone between the genetically and chromosomally well‐differentiated speciesSorex antinoriiandSorex araneusrace Vaud. Intermarker comparison clearly revealed coincidental centre and very abrupt clines for all three types of markers. The overall level of genetic differentiation between the two species must be strong enough to hinder asymmetric introgression. Cyto‐nuclear mismatches were also observed in the centre of hybrid zone. The significantly lower number of mismatches observed in males than in females possibly results from Y chromosome–mtDNA interactions. Results are compared with those previously reported in another hybrid zone betweenS. antinoriandS. araneusrace Cordon.
Effectiveness and safety of tranexamic acid administration during total knee arthroplasty
Authors: Lozano M. , Basora M. , Peidro L. , Merino I. , Segur J. M. , Pereira A. , Salazar F. , Cid J. , Lozano L. , Mazzara R. , Macule F. 
Published: March 2008

Background  The administration of tranexamic acid (TA) is associated with a decrease in the number of red blood cell (RBC) units transfused. However, concerns about its safety have hindered its broader use.Study Design and Methods  We evaluated the effect of TA on RBC transfusion and thromboembolic complications in total knee arthroplasty. We retrospectively studied 414 patients, 215 immediately before introducing TA treatment (control group) and after, in 199 patients without history of thromboembolic diseases (TA group). In a subgroup of patients, a lower extremities contrast venography was performed.Results  Fifty‐four per cent of control group patients were transfused with RBC while only 17·6% of TA group patients received RBCs. In the TA that group, those transfused received less units (2·83 vs. 1·89), showed smaller mean calculated perioperative blood loss and haemoglobin values at discharge were higher compared to control group (10·1 vs. 9·3 g/dl). Thromboembolic complications were diagnosed in 2·8% of the patients in the control group and in 1·5% in the TA group. Asymptomatic distal deep venous thrombosis was found in 54 (14·8%) of TA group patients and 54 (30·1%) of control patients. TA administration reduced the expenditure for RBC transfusion plus the cost of TA from €148·94 to 33·87 per patient.Conclusion  Routine administration of TA during total knee arthroplasty to patients without history of thromboembolic disease is associated with a 67% reduction in RBC transfusions and, in those transfused, with a reduction in the number of units administered. TA treatment was not associated with an increase in thromboembolic complications. Transfusion costs are significantly reduced.
Mountain pine beetle‐associated blue‐stain fungi are differentially adapted to boreal temperatures
Authors: Rice A. V. , Thormann M. N. , Langor D. W. 
Published: March 2008

SummaryMountain pine beetles (MPB) are the most serious pest of lodgepole pine in Canada and are likely to invade boreal jack pine forests. MPB vector three blue‐stain fungi, Grosmannia clavigera, Ophiostoma montium and Leptographium longiclavatum, which contribute to beetle success. Fungal survival at extreme boreal temperatures will contribute to their success in jack pine. Growth, sporulation and survival of the three fungi at −20 to 37°C were tested in vitro. Overwintering survival of G. clavigera and O. montium was assessed in vivo. All species grew at 5–30°C, with optimal growth at 20–25°C. Grosmannia clavigera and L. longiclavatum survived at −20°C, but O. montium died. Growth of G. clavigera and L. longiclavatum was inhibited at 30°C, but O. montium grew well. Grosmannia clavigera and O. montium overwintered in living pines. These results suggest that G. clavigera and L. longiclavatum were adapted to cold boreal winters but not hot summers, with the converse true for O. montium. Temperature tolerance varied among G. clavigera isolates. British Columbian and Californian isolates grew faster at 25°C than Albertan isolates. Isolates from Alberta and Idaho/Montana grew optimally at 20°C, while British Columbian and Californian isolates grew optimally at 25°C.
Reduction of albuminuria by angiotensin receptor blocker beyond blood pressure lowering: Evaluation in megsin/receptor for advanced glycation end products/inducible nitric oxide synthase triple transgenic diabetic nephropathy mouse model
Authors: OHTOMO SHUICHI , ITO MASAKI , IZUHARA YUKO , VAN YPERSELE DE STRIHOU CHARLES , MIYATA TOSHIO 
Published: March 2008

SUMMARY:Aim:  Antihypertensive agents inhibiting the renin‐angiotensin system (RAS), such as angiotensin II type 1 receptor blockers (ARB), are now part of the standard treatment of patients with diabetic nephropathy, regardless of the presence of systemic hypertension. Whether ARB achieve better renoprotection than other RAS‐independent antihypertensive drugs has been an issue of controversy. Several lines of large clinical studies provided better renoprotection of ARB. However, a recent meta‐analysis argued against additional benefits of ARB beyond blood pressure. We generated a novel mouse model of diabetic nephropathy; that is, megsin/receptor for advanced glycation end products/inducible nitric oxide synthase triple transgenic mice. This model is normotensive but progressively develops severe diabetic nephropathy that resembles those observed in humans.Methods:  In the present study, we tested whether olmesartan (ARB) achieves better renoprotection than amlodipine (calcium channel blocker). Drug treatment was initiated at the age of 6 weeks and lasted for 12 weeks.Results:  This model develops significant glomerular lesions and albuminuria even at the age of 5 weeks. Despite equal blood pressure lowering, only olmesartan suppressed the progression of albuminuria. Neither olmesartan nor amlodipine modified histological lesions.Conclusion:  Proteinuria and its reduction are known to predict the progression of diabetic nephropathy. Our results support the additional benefit of ARB beyond blood pressure lowering.