Differential introgression and the maintenance of species boundaries in an advanced generation avian hybrid zone

Background: Evolutionary processes, including selection and differential fitness, shape the introgression of genetic material across a hybrid zone, resulting in the exchange of some genes but not others. Differential introgression of molecular or phenotypic markers can thus provide insight into factors contributing to reproductive isolation. We characterized patterns of genetic variation across a hybrid zone between two tidal marsh birds, Saltmarsh (Ammodramus caudacutus) and Nelson’s (A. nelsoni) sparrows (n = 286), and compared patterns of introgression among multiple genetic markers and phenotypic traits. Results: Geographic and genomic cline analyses revealed variable patterns of introgression among marker types. Most markers exhibited gradual clines and indicated that introgression exceeds the spatial extent of the previously documented hybrid zone. We found steeper clines, indicating strong selection for loci associated with traits related to tidal marsh adaptations, including for a marker linked to a gene region associated with metabolic functions, including an osmotic regulatory pathway, as well as for a marker related to melanin-based pigmentation, supporting an adaptive role of darker plumage (salt marsh melanism) in tidal marshes. Narrow clines at mitochondrial and sex-linked markers also offer support for Haldane’s rule. We detected patterns of asymmetrical introgression toward A. caudacutus, which may be driven by differences in mating strategy or differences in population density between the two species. Conclusions: Our findings offer insight into the dynamics of a hybrid zone traversing a unique environmental gradient and provide evidence for a role of ecological divergence in the maintenance of pure species boundaries despite ongoing gene flow

Fine-scale population structure and asymmetrical dispersal in an obligate salt-marsh passerine, the Saltmarsh Sparrow (Ammodramus Caudacutus)

Understanding the spatial scale of gene flow can yield valuable insight into the ecology of an organism and guide conservation strategies. Fine-scale genetic structure is uncommon in migratory passerines because of their high vagility and presumed high dispersal abilities. Aspects of the behavior and ecology of some migratory species, however, may promote structure on a finer scale in comparison to their mobility. We investigated population genetic structure in the Saltmarsh Sparrow (Ammodramus caudacutus), a migratory passerine that breeds along the northeastern coast of the United States, where it is restricted exclusively to a narrow strip of patchily distributed tidal marsh habitat. Using genotyping with 10 microsatellite loci, we detected weak but significant population structure among Saltmarsh Sparrows from nine marshes on the breeding grounds between Scarborough, Maine, and Oceanside, New York. Genetic variation among marshes was largely consistent with a pattern of isolation by distance, with some exceptions. One inland marsh was genetically divergent despite its proximity to other sampled marshes, which suggests that mechanisms besides geographic distance influence population genetic structure. Bayesian clustering, multivariate analyses, and assignment tests supported a population structure consisting of five groups. Estimates of migration rates indicated variation in gene flow among marshes, which suggests asymmetrical dispersal and possible source-sink population dynamics. The genetic structure that we found in Saltmarsh Sparrows may result from natal philopatry and breeding-site fidelity, combined with restricted dispersal due to obligate dependence on a patchy habitat. Our findings suggest that fine-scale population structure may be important in some migratory passerines. Received 12 July 2011, accepted 1 February 2012

Genotype-environment associations support a mosaic hybrid zone between two tidal marsh birds

Local environmental features can shape hybrid zone dynamics when hybrids are bounded by ecotones or when patchily distributed habitat types lead to a corresponding mosaic of genotypes. We investigated the role of marsh-level characteristics in shaping a hybrid zone between two recently diverged avian taxa – Saltmarsh (Ammodramus caudacutus) and Nelson\u27s (A. nelsoni) sparrows. These species occupy different niches where allopatric, with caudacutus restricted to coastal marshes and nelsoni found in a broader array of wetland and grassland habitats and co-occur in tidal marshes in sympatry. We determined the influence of habitat types on the distribution of pure and hybrid sparrows and assessed the degree of overlap in the ecological niche of each taxon. To do this, we sampled and genotyped 305 sparrows from 34 marshes across the hybrid zone and from adjacent regions. We used linear regression to test for associations between marsh characteristics and the distribution of pure and admixed sparrows. We found a positive correlation between genotype and environmental variables with a patchy distribution of genotypes and habitats across the hybrid zone. Ecological niche models suggest that the hybrid niche was more similar to that of A. nelsoni and habitat suitability was influenced strongly by distance from coastline. Our results support a mosaic model of hybrid zone maintenance, suggesting a role for local environmental features in shaping the distribution and frequency of pure species and hybrids across space

Genotype-environment associations support a mosaic hybrid zone between two tidal marsh birds

Local environmental features can shape hybrid zone dynamics when hybrids are bounded by ecotones or when patchily distributed habitat types lead to a corresponding mosaic of genotypes. We investigated the role of marsh-level characteristics in shaping a hybrid zone between two recently diverged avian taxa – Saltmarsh (Ammodramus caudacutus) and Nelson\u27s (A. nelsoni) sparrows. These species occupy different niches where allopatric, with caudacutus restricted to coastal marshes and nelsoni found in a broader array of wetland and grassland habitats and co-occur in tidal marshes in sympatry. We determined the influence of habitat types on the distribution of pure and hybrid sparrows and assessed the degree of overlap in the ecological niche of each taxon. To do this, we sampled and genotyped 305 sparrows from 34 marshes across the hybrid zone and from adjacent regions. We used linear regression to test for associations between marsh characteristics and the distribution of pure and admixed sparrows. We found a positive correlation between genotype and environmental variables with a patchy distribution of genotypes and habitats across the hybrid zone. Ecological niche models suggest that the hybrid niche was more similar to that of A. nelsoni and habitat suitability was influenced strongly by distance from coastline. Our results support a mosaic model of hybrid zone maintenance, suggesting a role for local environmental features in shaping the distribution and frequency of pure species and hybrids across space

Antioxidant system of oral cavity in children with inflammatory diseases oral mucosa and acute forms of leukemia under the treatment

Kovach I. V., Khotimskаy J. V. Antioxidant system of oral cavity in children with inflammatory diseases oral mucosa and acute forms of leukemia under the treatment. Journal of Education, Health and Sport. 2017;7(1):387-395. eISSN 2391-8306. DOI http://dx.doi.org/10.5281/zenodo.276515http://ojs.ukw.edu.pl/index.php/johs/article/view/4246    The journal has had 7 points in Ministry of Science and Higher Education parametric evaluation. Part B item 754 (09.12.2016).754 Journal of Education, Health and Sport eISSN 2391-8306 7© The Author (s) 2017;This article is published with open access at Licensee Open Journal Systems of Kazimierz Wielki University in Bydgoszcz, PolandOpen Access. This article is distributed under the terms of the Creative Commons Attribution Noncommercial License which permits any noncommercial use, distribution, and reproduction in any medium, provided the original author(s) and source are credited. This is an open access article licensed under the terms of the Creative Commons Attribution Non Commercial License(http://creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted, non commercial use, distribution and reproduction in any medium, provided the work is properly cited.This is an open access article licensed under the terms of the Creative Commons Attribution Non Commercial License (http://creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted, non commercial use, distribution and reproduction in any medium, provided the work is properly cited.The authors declare that there is no conflict of interests regarding the publication of this paper.Received: 02.01.2017. Revised 16.01.2017. Accepted: 24.01.2017. ANTIOXIDANT SYSTEM OF ORAL CAVITY IN CHILDREN WITH INFLAMMATORY DISEASES ORAL MUCOSA AND ACUTE FORMS OF LEUKEMIA UNDER THE TREATMENT I. V. Kovach, J. V. Khotimskаy State Enterprise «Dnepropetrovsk Medical Academy under Ukrainian Ministry of Health»[email protected] Summary The children with inflammatory diseases of the oral mucosa on the background of acute leukemia develop antioxidant system pronounced changes, e.g. the level of its enzymatic and non-enzymatic components reduces. This increases oxidative homeostasis disorders and decreases catalase’s activity. We have developed  treatment-and-prophylactic complex containing quercetin mucosal gel and gel with a large number of polyphenols, flavonols, anthocyanins and catechins ("Vinaceous"), and dentilave "Lysomucoid", mixture of sanguinarine alkaloids disulfate and chelerythrine, anti-fungal and probiotic preparations. This complex has a pronounced stimulatory effect on the state of the antioxidant system, which largely determines the general condition of organs and tissues of the oral cavity. At the same time the developed therapeutic and preventive complex provides a consistently high level of functional activity of the antioxidant system in children with inflammatory diseases of the oral mucosa on the background of acute forms of leukemia in a year after treatment. The objective: to determine the activity of catalase in children with inflammatory diseases of the oral mucosa on the background of the acute form of leukemia in the dynamics of treatment. Materials and methods. 126 children aged 2-18 y.o. with acute lymphoblastic leukemia have been examined. All the children underwent clinical trials and then basic group and group of comparison was formed. In both groups the plaques were removed, full mouth debridement was made and systematically healthful procedures were done. Oral cavity hygiene was performed with the use of alcohol-free anti-inflammatory dentilave "Lysomucoid". The main group children additionally to oral hygiene used the developed therapeutic and prophylactic complexes. Results and Conclusions. The application of the developed therapeutic and prophylactic complexes, professional oral cavity hygiene and subsequent treatment applications had a pronounced  stimulating effect at the state of the antioxidant system, which depends greatly on the state of periodontal tissues and oral mucosa. The therapeutical method worked out provides high level of functional activity of the antioxidant system in all groups. This is especially important for acute leukemia children.Key words: leukemia, children, oral mucosa, antioxidant system, catalase

Relationship of phenotypic variation and genetic admixture in the Saltmarsh–Nelson\u27s sparrow hybrid zone

Hybridization is influential in shaping species\u27 dynamics and has many evolutionary and conservation implications. Identification of hybrid individuals typically relies on morphological data, but the assumption that hybrids express intermediate traits is not always valid, because of complex patterns of introgression and selection. We characterized phenotypic and genotypic variation across a hybrid zone between 2 tidal-marsh birds, the Saltmarsh Sparrow (Ammodramus caudacutus) and Nelson\u27s Sparrow (A. nelsoni) (n = 290), and we sought to identify morphological traits that could be used to classify admixed individuals. Sparrows were sampled from a total of 34 marshes, including 23 sympatric and 11 putatively allopatric marshes. Each individual was scored at 13 plumage traits, and standard morphometric data were collected. We used genotyping analysis at 24 microsatellite loci to categorize individuals into genotypic classes of pure, F1–F2, or backcrossed. Genetic data revealed that 52% of individuals sampled along the geographic transect were of mixed ancestry, and the majority of these were backcrossed. Traits related to the definition of plumage features (streaking, crown, and face) showed less overlap between genotypic classes than traits related to the amount or color of plumage features. Although morphological data performed well in distinguishing between the 2 taxa, pure and backcrossed individuals of each parental type could not be distinguished because of substantial overlap in plumage and morphology. We conclude that the discrimination of pure and hybrid individuals is not possible in the absence of genetic data. Our results have implications for conservation of pure populations, as extensive backcrossing throughout the hybrid zone may present challenges for monitoring pure species identified by morphology alone

Anthropogenic Habitats Facilitate Dispersal of an Early Successional Obligate: Implications for Restoration of an Endangered Ecosystem

Landscape modification and habitat fragmentation disrupt the connectivity of natural landscapes, with major consequences for biodiversity. Species that require patchily distributed habitats, such as those that specialize on early successional ecosystems, must disperse through a landscape matrix with unsuitable habitat types. We evaluated landscape effects on dispersal of an early successional obligate, the New England cottontail (Sylvilagus transitionalis). Using a landscape genetics approach, we identified barriers and facilitators of gene flow and connectivity corridors for a population of cottontails in the northeastern United States. We modeled dispersal in relation to landscape structure and composition and tested hypotheses about the influence of habitat fragmentation on gene flow. Anthropogenic and natural shrubland habitats facilitated gene flow, while the remainder of the matrix, particularly development and forest, impeded gene flow. The relative influence of matrix habitats differed between study areas in relation to a fragmentation gradient. Barrier features had higher explanatory power in the more fragmented site, while facilitating features were important in the less fragmented site. Landscape models that included a simultaneous barrier and facilitating effect of roads had higher explanatory power than models that considered either effect separately, supporting the hypothesis that roads act as both barriers and facilitators at all spatial scales. The inclusion of LiDAR-identified shrubland habitat improved the fit of our facilitator models. Corridor analyses using circuit and least cost path approaches revealed the importance of anthropogenic, linear features for restoring connectivity between the study areas. In fragmented landscapes, human-modified habitats may enhance functional connectivity by providing suitable dispersal conduits for early successional specialists

Influence of ozone therapy on oral tissue in modeling of chronic recurrent aphthous stomatitis

Chronic recurrent aphthous stomatitis (CRAS) belongs to the group of chronic, inflammatory, ulcerative diseases of the oral mucosa. The aim of this study was to determine the effects of ozone on the morphofunctional peculiarities of the soft tissues in modeling chronic recurrent aphthous stomatitis. We performed experimental investigation for study of the morpho-functional state of tissues of the oral mucosa in CRAS with using of previously proposed and widely used modeling scheme with ovalbumin and aluminum hydroxide. Two groups of animals were formed (Dutch rabbits, males, aging three-month, weighting 2-2.4 kg). Group of 8 animals with obtained mucosal changes was our comparison group. Other group of 8 animals with obtained mucosal changes was treated by ozone therapy. Histological investigation has been performed. Microscopical examination of tissue had shown that ozone therapy reduces inflammation and edema and is useful in wound healing in soft tissue as disappearance of necrobiotic processes, epithelialization of aphthous defect, growth of akantotic bands, pronounced reducing of inflammatory cells and changing of cellular ratio (with of neutrophils part from 38.30±2.46% to 6.34±0.63%, eosinophils from 5.49±0.23% to 2.87±0.05%), restoration of the cellular layers of the epithelium, moderately pronounced sclerosis of the papillary layer of the lamina propria. Described results allow to conclude that correction of tissual changes in chronic recurrent aphthous stomatitis could be obtained with ozone therapy using. Хронический рецидивирующий афтозный стоматит (ХРАС) относится к группе хронических, воспалительных, язвенных заболеваний слизистой оболочки полости рта. Целью исследования явилось определение влияния озона на морфофункциональные особенности мягких тканей ротовой полости при моделировании хронического рецидивирующего афтозного стоматита. Проведено экспериментальное исследование для изучения морфофункционального состояния тканей слизистой оболочки полости рта при ХРАС на основе ранее предложенной и широко применяемой модели с использованием овальбумина и гидроксида алюминия. Сформированы две группы животных (голландские кроли, самцы, возраст три месяца, вес 2-2,4 кг). I группа из 8 животных с изменениями слизистой оболочки составила группу сравнения. II группа из 8 животных с изменениями слизистой оболочки ротовой полости получала озонотерапию. Проведено гистологическое исследование. Микроскопическое исследование тканей показало, что озонотерапия уменьшает признаки воспаления, отека и способствует заживлению язвенных дефектов: наблюдается как исчезновение некробиотических процессов, эпителизация афтозных поражений, акантоз, выраженное уменьшение воспалительных клеток и изменение клеточного отношения - нейтрофилы с 38,30±2,46% до 6,34±0,63%, эозинофилы - с 5,49±0,23% до 2,87±0,05%, восстановление клеточных слоев эпителия, умеренно выраженный склероз сосочкового слоя собственной пластинки. Полученные результаты позволяют заключить, что озонотерапия способствует коррекции тканевых изменений при хроническом рецидивирующем афтозном стоматите

Influence of tricalcium silicate on course of traumatic pulpitis

The use of Tricalcium Silicate (TS) as an odontotropic preparation makes it possible to create a hermetic crown restoration with a high degree of adhesion. However, the use of TS silicate by direct pulp capping remains disputable. The aim of this study was to determine the effects of TS on course of traumatic pulpitis by detection of morpho-functional peculiarities of changes in pulp tissue. We performed experimental investigation (on rabbits, males, aging three-month) for study of the morphofunctional changes of the pulp tissues with modeling of traumatic pulpitis and direct pulp capping with TS preparation (8 animals, investigated group) and calcium hydroxide (Calasept, NORDISKA DENTAL) preparation (8 animals, comparison group). After 2nd and 6th weeks tissues of tooth were fixed in 10% formalin with performing routine proceeding after decalcification and making histological slides which were investigated. Manifestations of protective adaptive mechanisms have been revealed in the form of inflammatory process two weeks after the injury in the pulp tissue with its resolution six weeks after performing of direct pulp capping with TS with replacement of necrotic area by connective tissue with their delimitation from viable pulp tissue against a background of intensive formation of capillaries. Morphometric study proved dynamical changes of vascular number cross-sections per 1 mm2 from 69.31±4.76 (2 weeks) to 47.38±4.12 (6 weeks) with 49.2±3.47 vascular density in intact group. Cellular density of odontoblasts as changed from 3.92±1.03 x103 per 1 mm2 (2 weeks) to 7.49±1.51 x103 per 1 mm2 (6 weeks) with 8.3±1.02 x103 per 1 mm2 cellular density in intact group. Thus it can be argued that the use of TS as a material for direct pulp capping promotes more active regeneration processes. Целью исследования явилось определение влияния трикальцийсиликата на течение травматического пульпита. Поставлен эксперимент на 3-месячных кроликахсамцах для изучения морфофункциональных изменений ткани пульпы с моделированием травматического пульпита и прямым покрытием пульпы трикальцийсиликатом (8 животных, исследуемая группа) и гидроксидом кальция (Calasept, NORDISKA DENTAL) (8 животных, группа сравнения). Спустя 2 и 6 недели ткани зуба фиксировали в 10% формалине и после декальцификации и рутинной проводки исследовали гистологические препараты. Спустя 2 недели после нанесения травмы в ткани пульпы обнаружены проявления защитно-приспособительных механизмов в виде воспалительного процесса с его разрешением, при котором наблюдается замещение зоны некроза соединительной тканью на фоне интенсивного новообразования капилляров, что характеризуется изменением плотности сосудов микроциркуляторного русла. Морфометрическое исследование показало динамические изменения количества сосудистых сечений с 69,31±4,76/мм2 (2 недели) до 47,38±4,12/мм2 (6 недель) при 49,2±3,47/мм2 в интактной группе. Плотность одонтобластов изменилась с 3,92±1,03×103/мм2 (2 недели) до 7,49±1,51×103/мм2 (6 недель) при 8,3±1,02×103/мм2 клеточной плотности в интактной группе. Таким образом, следует предположить, что использование трикальцийсиликата в качестве материала для прямого покрытия пульпы способствует более активным процессам регенерации