bluuebunny/crossref_metadata_2025_split huggingface dataset:
Habitat selection in birds feeding on ocean shores: landscape effects are important in the choice of foraging sites by oystercatchers
Authors: Schlacher Thomas A. , Meager Justin J. , Nielsen Tara 
Published: April 2013

AbstractFood availability is a fundamental determinant of habitat selection in animals, including shorebirds foraging on benthic invertebrates. However, the combination of dynamic habitats, patchy distributions at multiple spatial scales, and highly variable densities over time can make prey less predictable on ocean‐exposed sandy shores. This can, hypothetically, cause a mismatch between prey and consumer distributions in these high‐energy environments. Here we test this prediction by examining the occurrence of actively foraging pied oystercatchers (Haematopus longirostris) in relation to physical habitat attributes and macrobenthic prey assemblages on a 34 km long, high‐energy beach inEasternAustralia. We incorporate two spatial dimensions: (i) adjacent feeding and non‐feeding patches separated by 200 m and (ii) landscape regions with and without foraging birds separated by 2–17 km. There was no support for prey‐based or habitat‐based habitat choice at the smaller dimension, with birds being essentially randomly distributed at the local scale. Conversely, at the broader landscape dimension, the distribution of oystercatchers was driven by the density of their prey, but not by attributes of the physical beach environment. This scale‐dependence suggests that, on open‐coast beaches, landscape effects modulate how mobile predators respond to variations in prey availability.
Inhibition of in vivo Slicer activity of Argonaute protein 1 by the viral 2b protein independent of its dsRNA‐binding function
Authors: Feng Lei , Duan Cheng‐Guo , Guo Hui‐Shan 
Published: April 2013

SummaryThe 2b protein of Cucumber mosaic virus (CMV) has several unique properties, such as targeting to the nucleolus and interaction with both Argonautes (AGOs) and short and long double‐stranded RNA (dsRNA). We have recently uncoupled the domain requirements for dsRNA binding and nucleolar targeting from the physical interactions with AGO proteins, and have found that the direct 2b–AGO interaction is sufficient to inhibit the in vitro AGO1 Slicer function independent of the other biochemical properties of 2b. Because the AGO binding activity of 2b is not required for its suppressor function in vivo, this raises the question of whether in vivo 2b–AGO interaction is possible to inhibit the in vivo AGO Slicer function. In this study, by taking advantage of a technology for the production of artificial trans‐acting small interfering RNA (tasiRNA), a process uniquely associated with AGO1‐mediated in vivo Slicer activity, we demonstrated that the expression of the 2b protein in planta interfered with the production of tasiRNA. Through further detailed analysis with deletion mutants of 2b proteins, we found that the inhibition of in vivo AGO1 Slicer function required the nucleolar localization signal (NoLS), in addition to the AGO‐binding domain, of the 2b protein. Our finding demonstrates that in vivo 2b–AGO1 interaction is sufficient to inhibit AGO1 Slicer function independent of the dsRNA‐binding activity of the 2b protein.
Counting neurons is not as easy as ‘one‐two, three’
Authors: Kapur R. P. 
Published: April 2013

AbstractAn accurate determination of the number of neurons in a segment of bowel is fundamental to establish population norms and identify neurodegenerative conditions, including age‐related loss of myenteric ganglion cells. Although the latter phenomenon has been observed by several laboratories in various mammals, in this issue of Neurogastroenterology and Motility, Gamage et al. present evidence that colonic myenteric ganglion cells are maintained in aged mice. These discordant findings prompt a thoughtful consideration, the range of variables affecting the accuracy of neuronal counts and the survival of neuronal populations in aging animals.
Combining frost tolerance, high grain yield and good pasta quality in durum wheat
Authors: Longin Carl Friedrich Horst , Sieber Alisa‐Naomi , Reif Jochen C. 
Published: April 2013

AbstractGrowing in Central Europe winter instead of spring durum wheat would substantially increase yield potential but is currently hampered by the lack of knowledge of frost tolerance present in elite material. The objectives of our survey were to (i) study the genetic variability and heritability of frost tolerance and its association with other important agronomic and quality traits in durum wheat, (ii) examine the potential to combine frost tolerance with high quality and high grain yield and (iii) investigate the consequences of the heritabilities and associations among traits on the optimum design of a multistage selection programme for winter durum wheat. We investigated 101 elite winter durum wheat lines and four commercial checks in field trials at four locations. Four agronomic as well as nine quality traits were recorded. In addition, frost tolerance was evaluated using a semi‐controlled test resulting in high‐quality phenotypic data. Genotypic variances (σ²G) were significantly larger than zero for all traits, and heritabilities were moderate to high. Several elite durum wheat lines exhibited a frost tolerance comparable to that of two frost‐tolerant Triticum aestivum varieties. Frost tolerance was not negatively associated with other important agronomic and quality traits. The high quality of the phenotypic data for frost tolerance evaluated in a semi‐controlled test suggests that this is a cost‐efficient approach to consider frost tolerance at early stages of a multistage durum wheat breeding programme.
Use of barley seed vigour to discriminate drought and cold tolerance in crop years with high seed vigour and low trait variation
Authors: Ullmannová Kamila , Stř eda Tomáš , Chloupek Oldř ich 
Published: April 2013

AbstractSeed vigour is a precondition for early and homogenous field emergence of barley, in addition to effective malting. This study aimed to assess the selection of barley varieties by using seed vigour as the indicator. Seed vigour of barley (quantified as the germination percentage) was evaluated under drought (−0.2 MPa) and temperature stress (10°C). At two locations over a 3‐year period, 1 population of 133 Derkado × B83‐12/21/5 doubled haploid (DH) lines (and parents) was evaluated for seed vigour, of which 108 DH lines were assessed for three malting parameters. The relatively high values of vigour during the 3‐year period (overall average 94–95%) probably impeded high variations in genetic potential. A total of 27 DH lines of the 133 evaluated showed transgression for vigour (up to 98%) in comparison with the parents (Derkado: 96%; B83: 92%). In conclusion, caution should be applied when selecting for seed vigour, even in good crop years with high levels of seed vigour and low trait variations. Such selection might improve vigour, particularly in crop years with unsuitable weather conditions.
MicroRNA‐based molecular markers: a novel PCR‐based genotyping technique in Brassica species
Authors: Fu Donghui , Ma Bi , Mason Annaliese S. , Xiao Meili , Wei Lijuan , An Zeshan 
Published: April 2013

AbstractDNA‐based molecular markers play a significant role in gene mapping, genetic diversity analysis, germplasm evaluation and molecular marker‐assisted selection. A combination of desirable marker characteristics such as abundant polymorphism, good stability, ease of production and high efficiency is difficult to achieve when utilizing traditional molecular marker systems. MicroRNAs are a type of endogenous non‐coding RNAs prevalent in the genomes of many organisms. The high conservation of miRNA and pre‐miRNA sequences provides an opportunity to develop a novel molecular marker type. We downloaded 82 miRNA sequences from the Brassica miRBase database and designed 46 single miRNA‐based primers which could be randomly combined to generate primer pairs. A proportion of these primer pairs were validated for transferability and polymorphism using DNA from 16 varieties of six Brassica species. The percentage of polymorphic primer pairs were 28.1%, and the average polymorphism information content (PIC) value for the 34 primer pairs was 0.43. Good transferability was verified across species. These results indicate that miRNA‐based markers provide a novel genotyping technique with low costs, high efficiency, stability and good transferability.
Quantifying the impact of daily and seasonal variation in sap pH on xylem dissolved inorganic carbon estimates in plum trees
Authors: Erda F. G. , Bloemen J. , Steppe K. 
Published: April 2013

AbstractIn studies on internal CO2 transport, average xylem sap pH (pHx) is one of the factors used for calculation of the concentration of dissolved inorganic carbon in the xylem sap ([]). Lack of detailed pHx measurements at high temporal resolution could be a potential source of error when evaluating [] dynamics. In this experiment, we performed continuous measurements of CO2 concentration ([CO2]) and stem temperature (Tstem), complemented with pHx measurements at 30‐min intervals during the day at various stages of the growing season (Day of the Year (DOY): 86 (late winter), 128 (mid‐spring) and 155 (early summer)) on a plum tree (Prunus domestica L. cv. Reine Claude d'Oullins). We used the recorded pHx to calculate [] based on Tstem and the corresponding measured [CO2]. No statistically significant difference was found between mean [] calculated with instantaneous pHx and daily average pHx. However, using an average pHx value from a different part of the growing season than the measurements of [CO2] and Tstem to estimate [] led to a statistically significant error. The error varied between 3.25 ± 0.01% under‐estimation and 3.97 ± 0.01% over‐estimation, relative to the true [] data. Measured pHx did not show a significant daily variation, unlike [CO2], which increased during the day and declined at night. As the growing season progressed, daily average [CO2] (3.4%, 5.3%, 7.4%) increased and average pHx (5.43, 5.29, 5.20) decreased. Increase in [CO2] will increase its solubility in xylem sap according to Henry's law, and the dissociation of [] will negatively affect pHx. Our results are the first quantifying the error in [] due to the interaction between [CO2] and pHx on a seasonal time scale. We found significant changes in pHx across the growing season, but overall the effect on the calculation of [] remained within an error range of 4%. However, it is possible that the error could be more substantial for other tree species, particularly if pHx is in the more sensitive range (pHx > 6.5).
Multistate Survival Models as Transient Electrical Networks
Authors: Butler Ronald W. , Bronson Douglas A. 
Published: April 2013

ABSTRACTIn multistate survival analysis, the sojourn of a patient through various clinical states is shown to correspond to the diffusion of 1 C of electrical charge through an electrical network. The essential comparison has differentials of probability for the patient to correspond to differentials of charge, and it equates clinical states to electrical nodes. Indeed, if the death state of the patient corresponds to the sink node of the circuit, then the transient current that would be seen on an oscilloscope as the sink output is a plot of the probability density for the survival time of the patient. This electrical circuit analogy is further explored by considering the simplest possible survival model with two clinical states, alive and dead (sink), that incorporates censoring and truncation. The sink output seen on an oscilloscope is a plot of the Kaplan–Meier mass function. Thus, the Kaplan–Meier estimator finds motivation from the dynamics of current flow, as a fundamental physical law, rather than as a nonparametric maximum likelihood estimate (MLE). Generalization to competing risks settings with multiple death states (sinks) leads to cause‐specific Kaplan–Meier submass functions as outputs at sink nodes. With covariates present, the electrical analogy provides for an intuitive understanding of partial likelihood and various baseline hazard estimates often used with the proportional hazards model.
Significance of screening antibodies to hepatitis B virus core antigen among Syrian blood donors
Authors: Muselmani W. , Habbal W. , Monem F. 
Published: April 2013

SUMMARYBackgroundHepatitis B virus (HBV) transmission via hepatitis B surface antigen (HBsAg)‐negative blood donors has been reported. While many countries have implemented screening antibodies to hepatitis B core antigen (anti‐HBc) to further enhance transfusion safety, HBsAg is still the only obligatory HBV screening test of blood donors in Syria.ObjectiveTo evaluate the significance of screening anti‐HBc to reduce the risk of transfusion transmitted HBV infection in Syria.Methods/MaterialsA cohort cross‐sectional prospective study included 1939 healthy blood donors assigned at the blood transfusion center of Damascus University. All donors were tested for HBsAg and anti‐HBc. HBsAg‐negative, anti‐HBc‐positive sera were further tested quantitatively for antibodies to hepatitis B surface antigen (anti‐HBs) and ‘anti‐HBc alone’ sera were considered for HBV quantitative real time polymerase chain reaction (qPCR).ResultsAmong 1913 HBsAg‐negative donors, 215 (11·2%) were anti‐HBc‐positive including 125 anti‐HBs high‐positive and 59 anti‐HBs low‐positive donors. The remaining 31 donors were ‘anti‐HBc alone’, five of which were HBV DNA‐positive.ConclusionOur results suggest including anti‐HBc as an additional screening test for blood donors in Syria to reduce the risk of HBV transmission. As the most cost‐effective measure, anti‐HBc‐positive donors should be tested quantitatively for anti‐HBs and only donors with no or low (<100 IU L–1) anti‐HBs should be deferred.
Methods of freezing cord blood hematopoietic stem cells
Authors: Antoniewicz‐Papis Jolanta , Lachert Elżbieta , Woźniak Jolanta , Janik Karolina , Łętowska Magdalena 
Published: April 2013

BackgroundCord blood (CB) is a valuable source of hematopoietic stem cells (HSCs). Extended storage of CB is possible provided that validated cryopreservation procedures are used. The study objective was to determine optimal methods of CB cryopreservation.Study Design and MethodsIn the study we 1) compared the effect of two‐step cryopreservation and controlled‐rate freezing method on the postthaw quality of CB (Study A) and 2) evaluated the postthaw quality of HSC fractions isolated from CB with various methods and frozen with controlled‐rate freezing method (Study B). The same cryoprotectant mixture was used for 20 CB units (Study A) and 122 CB units (Study B).ResultsIn Study A, 13.79 × 108 and 13.29 × 108 initial white blood cell (WBC) counts decreased to 6.38 × 108 and 6.02 × 108 after thaw for the two methods, respectively. The mononuclear cell (MNC) counts decreased from 5.90 × 108 to 3.71 × 108 and from 5.64 × 108 to 3.47 × 108 dependent on the method. MNC viability decreased from 99.0% to 97.4% for the former and from 98.5% to 97.2% for the latter method. The differences were insignificant. In Study B, postthaw WBC recovery in HSC fractions was 74.4% to 103.5%, MNC recovery 106.4% to 118.5%, CD34+ cell recovery 102.5% to 150.2%, and MNC viability 94.1% to 97.4%.ConclusionNeither the cryopreservation procedure nor the freezing of isolated HSCs affected product quality, which may indicate that various freezing methods can be used for cell banking provided the they follow recommendations of good manufacturing practice and Directive 2004/33/EC.
Sterility testing of minimally manipulated cord blood products: validation of growth‐based automated culture systems
Authors: Akel Salem , Lorenz Joan , Regan Donna 
Published: April 2013

BackgroundThe St Louis Cord Blood Bank submitted a biologics license application for cord blood (CB) products processed by PrepaCyte‐CB (BioE), supported with a validation study of a microbial detection system for product sterility testing (BACTEC‐FX, Becton Dickinson). This article provides the validation approach followed to fulfill Food and Drug Administration requirements pertinent to sterility testing method.Study Design and MethodsSystem qualification, culture media quality verification, and validation of CB processing by‐product (CB‐BP) sample as surrogate to final product for sterility testing were followed by studies evaluating method sensitivity, specificity, reproducibility, ruggedness or robustness, and bacteriostatic or fungistatic effect of CB‐BP sample. CB‐BP cultures and control samples were formulated using BACTEC Plus Aerobic/F, Plus Anaerobic/F, and Myco F/Lytic media. Samples were seeded with selected test organisms (n = 13 at 10‐100 colony‐forming units [CFUs] per vial) and cultured for 14 days (bacterial) and 30 days (fungal).ResultsUnder testing conditions, no stasis effect of test sample on microbial growth and no false‐positive or false‐negative results were reported. Although a 7‐day culture was sufficient to detect all validation test organisms seeded at ≤26 CFUs/vial, growth in actual product sterility testing practice may require a 10‐ to 14‐day culture. Assay reproducibility was uncertain at very low bioburden (<10 CFUs/vial). Growth time to detection neither varied between different media lots nor prolonged in culture vials with loading delay (6‐8 hr at room temperature).ConclusionBACTEC‐FX culture and detection system and BACTEC media formulae have high detection capability and can be effectively validated for sterility testing of CB products.
A dynamic flow‐chamber‐based adhesion assay to assess canine platelet–matrix interactions in vitro
Authors: Ferkau Annika , Ecklebe Silke , Jahn Kira , Calmer Simone , Theilmeier Gregor , Mischke Reinhard 
Published: April 2013

BackgroundDynamic adhesion assays allow the examination of platelet dysfunction and drug effects on platelet function.ObjectiveThe purpose of the study was to optimize several parameters such as type and concentration of collagen, wall shear stress, and the concentration of the platelet‐activating agonist in a new biochip perfusion chamber for the study of canine platelets.MethodsAfter fluorescent staining of platelets, citrated blood of 10 healthy dogs was perfused through the flow chamber coated with different concentrations of canine or bovine skin collagen. Wall shear stress ranged from 14 to 60 dynes/cm2. Protease‐activating receptor 4 (PAR 4) agonist was used for platelet activation. After perfusion, platelet attachment to the collagen matrix was quantified based on fluorescent imaging. Total platelet covered area and average size of platelet covered areas were measured by planimetry.ResultsCanine platelet adhesion was supported by ≥ 200 μg/mL canine collagen, but not bovine skin collagen. Consistent results were obtained with a wall shear stress of 14 dynes/cm2, whereas higher wall shear stress resulted in increased variability. Platelet activation with PAR 4 agonist increased the total platelet covered area and the average size of platelet covered areas.ConclusionsThis study indicates the need to carefully select collagen type and concentration to assess canine thrombus formation in a dynamic flow chamber. The established method should be a useful tool to determine changes in platelet–matrix interactions as an indicator of platelet activation or platelet dysfunction in dogs.
Use of bovine pericardium (Tutopatch®) graft for surgical repair of deep melting corneal ulcers in dogs and corneal sequestra in cats
Authors: Dulaurent Thomas , Azoulay Thierry , Goulle Frédéric , Dulaurent Alice , Mentek Marielle , Peiffer Robert L. , Isard Pierre‐François 
Published: April 2013

AbstractObjectiveTo evaluate the efficacy of bovine pericardium (BP) graft in the treatment of deep melting corneal ulcers in three dogs and corneal sequestra in three cats.ProcedureThree dogs with keratomalacia affecting the deep third of the stroma and three cats with corneal sequestrum were evaluated and underwent surgery. Following keratectomy, BP material was placed into the keratectomy bed and sutured to the recipient cornea with 9/0 polyglactin suture material. Postoperative treatment with topical and systemic antibiotics, systemic nonsteroidal anti‐inflammatory agents, and topical atropine was prescribed. Follow‐up examinations were carried out 1, 2 weeks, 1 and 2 months after the surgery and consisted of a complete ophthalmic examination. Optical coherence tomography (OCT) was performed 1 and 2 months after the surgery in one dog and in one cat.ResultsAt 1 week, corneal neovascularization was present around the BP graft in all cases. Four weeks after the BP graft, in two dogs and in all cats, the vascularization was regressing and the graft was integrated into the cornea, which was regaining transparency. Topical treatment with anti‐inflammatory agents was then prescribed for 2 weeks. Two months after the surgery, 5 of 6 corneas in two dogs and three cats had healed with focal corneal scarring. The remaining dog had progression of the keratomalacia involving the deep BP graft that required additional surgery, but became blind.ConclusionBovine pericardium graft offers a promising option for surgical reconstruction of the cornea following keratectomy for the management of corneal ulcers and sequestra.
Translating stem cell therapies: The role of companion animals in regenerative medicine
Authors: Volk Susan W. , Theoret Christine 
Published: April 2013

AbstractVeterinarians and veterinary medicine have been integral to the development of stem cell therapies. The contributions of large animal experimental models to the development and refinement of modern hematopoietic stem cell transplantation were noted nearly five decades ago. More recent advances in adult stem cell/regenerative cell therapies continue to expand knowledge of the basic biology and clinical applications of stem cells. A relatively liberal legal and ethical regulation of stem cell research in veterinary medicine has facilitated the development and in some instances clinical translation of a variety of cell‐based therapies involving hematopoietic stem cells and mesenchymal stem cells, as well as other adult regenerative cells and recently embryonic stem cells and induced pluripotent stem cells. In fact, many of the pioneering developments in these fields of stem cell research have been achieved through collaborations of veterinary and human scientists. This review aims to provide an overview of the contribution of large animal veterinary models in advancing stem cell therapies for both human and clinical veterinary applications. Moreover, in the context of the “One Health Initiative,” the role veterinary patients may play in the future evolution of stem cell therapies for both human and animal patients will be explored.
Connexin dynamics in the privileged wound healing of the buccal mucosa
Authors: Davis Nicola G. , Phillips Anthony , Becker David L. 
Published: April 2013

AbstractWound closure is fundamental to maintaining tissue homeostasis; a plethora of processes and signals must be coordinated, and gap junctions play a critical role. Some tissues exhibit privileged healing, such as buccal mucosa, repairing more rapidly, but gap junction connexin dynamics during wound healing in such tissues have not been investigated. To determine connexin changes during this rapid healing process, incisional wounds were made in the cheeks of mice and microscopically observed. We discovered that buccal mucosa wound edge keratinocytes do not form a thin tongue of migratory cells like epidermis; instead, a wedge of cells rapidly moves into the wound. The dorsal surfaces of opposing sides of the wounds then touch and join in a “V,” which subsequently fills up with cells to form a “delta” that remodels into a flat sheet. Immunostaining showed that connexin26, connexin30, and connexin43 are expressed at significantly higher levels in the buccal mucosa than the epidermis and that, unlike the skin, all three are rapidly down‐regulated at the wound edge within 6 hours of wounding. This rapid down‐regulation of all three connexins may in part underlie the rapid healing of the buccal mucosa.