The determination of fibroblast and keratinocyte death types after their transplantation into γ-irradiated porous scaffold in vitro

In the course of radiation therapy, normal cells surrounding the tumor are also irradiated. During and after irradiation, they undergo a series of structural and metabolic changes, which can lead to cell death or transformation. Therefore, when planning and conducting radiation therapy, the effects of radiation on normal cells are taken into account with the aim of predicting and further correcting post-radiation complications, including the development of radiation burns and ulcers. Radiation skin burns are characterized by a prolonged course of the wound healing process, which is accompanied by a sharp decrease in the number of viable cells in the affected tissue from the first hours of irradiation. The type of cell death can significantly impact the effectiveness of radiation therapy and post-radiation complication correction. Therefore, it is important to study the type of their death in irradiated three-dimensional culture on a model of irradiated dermal equivalent, which is widely used today for modeling biological processes. To detect the pathways of cell death, the levels of reactive oxygen species, cell viability, number of cells undergoing autophagy, apoptosis, and necrosis, the content of active caspases 3, 8, and 9 was fluorometrically measured in the irradiated 3D cell culture by laser scanning confocal microscopy. It was determined that the transplantation of fibroblasts and keratinocytes into the irradiated dermal equivalent contributed to an increase in the overall viability of cells of the equivalent and led to a significant decrease in the concentration of free oxygen forms in the irradiated equivalent. Cells within the irradiated equivalent were not evenly distributed in terms of their quantity and viability, with an overall decrease in the cell count over time. A cluster of equivalent cells with significantly higher viability was formed around the transplant. At the same time, the fibroblasts of the transplant were found to be more resistant to the cytotoxic factors of the post-irradiation culture environment compared to keratinocytes. It was demonstrated that non-irradiated dermal equivalent cells predominantly undergo cell death through autophagy, irradiated equivalent cells primarily undergo necrosis, and after the introduction of the transplant, cell death predominantly occurs through apoptosis. In irradiated culture, both with and without transplantation, there is an increase in the content of effector caspase 3. Cells in irradiated culture undergo apoptosis through the mitochondrial mechanism (with a predominance of active caspase 9), while in irradiated culture with the introduction of the transplant, the receptor-mediated mechanism of apoptosis dominates (with a predominance of active caspase 8). The obtained results can be important for the development of new effective methods of therapy for radiation burns, chronic ulcers and wounds of various etiologies

Cross-talk between high light stress and plant defence to the two-spotted spider mite in Arabidopsis thaliana

Little is known about how plants deal with arthropod herbivores under the fluctuating light intensity and spectra which occur in natural environments. Moreover, the role of simultaneous stress such as excess light (EL) in the regulation of plant responses to herbivores is poorly characterized. In the current study, we focused on a mite-herbivore, specifically, the two-spotted spider mite (TSSM), which is one of the major agricultural pests worldwide. Our results showed that TSSM-induced leaf damage (visualized by trypan blue staining) and oviposition rate (measured as daily female fecundity) decreased after EL pre-treatment in wild-type Arabidopsis plants, but the observed responses were not wavelength specific. Thus, we established that EL pre-treatment reduced Arabidopsis susceptibility to TSSM infestation. Due to the fact that a portion of EL energy is dissipated by plants as heat in the mechanism known as non-photochemical quenching (NPQ) of chlorophyll fluorescence, we tested an Arabidopsis npq4-1 mutant impaired in NPQ. We showed that npq4-1 plants are significantly less susceptible to TSSM feeding activity, and this result was not dependent on light pre-treatment. Therefore, our findings strongly support the role of light in plant defence against TSSM, pointing to a key role for a photo-protective mechanism such as NPQ in this regulation. We hypothesize that plants impaired in NPQ are constantly primed to mite attack, as this seems to be a universal evolutionarily conserved mechanism for herbivores

Ecological Invasion, Roughened Fronts, and a Competitor's Extreme Advance: Integrating Stochastic Spatial-Growth Models

Both community ecology and conservation biology seek further understanding of factors governing the advance of an invasive species. We model biological invasion as an individual-based, stochastic process on a two-dimensional landscape. An ecologically superior invader and a resident species compete for space preemptively. Our general model includes the basic contact process and a variant of the Eden model as special cases. We employ the concept of a "roughened" front to quantify effects of discreteness and stochasticity on invasion; we emphasize the probability distribution of the front-runner's relative position. That is, we analyze the location of the most advanced invader as the extreme deviation about the front's mean position. We find that a class of models with different assumptions about neighborhood interactions exhibit universal characteristics. That is, key features of the invasion dynamics span a class of models, independently of locally detailed demographic rules. Our results integrate theories of invasive spatial growth and generate novel hypotheses linking habitat or landscape size (length of the invading front) to invasion velocity, and to the relative position of the most advanced invader.Comment: The original publication is available at www.springerlink.com/content/8528v8563r7u2742

Biochemical mechanisms of skin radiation burns inhibition and healing by the volumetric autotransplantation of fibroblasts and of keratinocytes with fibroblasts composition

Mechanisms of influence of volumetric autotransplantation of fibroblasts and of the mixture of fibroblasts and keratinocytes on the development of the local 3rd degree X-ray burn and the radiation skin ulcer in guinea pigs were investigated. We used deepadministration into the irradiation zone on its perimeter of 6 doses, which contained (150–160)×103 fibroblasts and (130–140)×103 keratinocytes in 100 µl. It is shown that this autotransplantation carried out 1 hour after the irradiation, and then every 24 hours, reduces the area of burn on the 35th day, compared to the control by 63%. Radiation ulcer appears on the 10th day after irradiation and is completely healed on the 25th day. With the same regimen of administration of only fibroblasts containing (200–210)×103 cells in 100 µl, these parameters of treatment were equal to 31% on 4th and 35th day, respectively. It is shown that as a result of radiation in the area of burn the level of gene expression of collagen types I and III, elastin, fibronectin, vinculin, decorin, hyaluronansynthases 1, 2, 3, matrix metalloproteinases 1, 2, 3, 7, 9 and hyaluronidase is reduced. Besides, in the burn area the level of gene expression of transforming growth factor α, fibroblast growth factors 1, 2, 8 and anti-inflammatory cytokines – interleukin 10 and transforming growth factor-β1 – is reduced, while the level of gene expression of proinflammatory cytokine (interleykin1β) increases. Both types of autotransplantation cause the growth of the expression level of all the structural genes and regulatory proteins of biopolymers and decrease in the expression level of interleukin 1β, which leads to activation of tissue regeneration and healing of the burn wound. Reasonsfor the higher efficiency of autotransplantation using the mixture of fibroblasts and keratinocytes compared to autotransplantation by fibroblasts only are both the larger total number of live cells regularly replacing dead cells in the burn area, and mutual stimulation of auto-fibroblasts and auto-keratinocytes to proliferate and to synthesize biologically active substances, i.e. cytokines and growth factors.</jats:p

Abscisic Acid Insensitive 4 transcription factor is an important player in the response of Arabidopsis thaliana to two-spotted spider mite (Tetranychus urticae) feeding.

Plants growing in constantly changeable environmental conditions are compelled to evolve regulatory mechanisms to cope with biotic and abiotic stresses. Effective defence to invaders is largely connected with phytohormone regulation, resulting in the production of numerous defensive proteins and specialized metabolites. In our work, we elucidated the role of the Abscisic Acid Insensitive 4 (ABI4) transcription factor in the plant response to the two-spotted spider mite (TSSM). This polyphagous mite is one of the most destructive herbivores, which sucks mesophyll cells of numerous crop and wild plants. Compared to the wild-type (Col-0) Arabidopsis thaliana plants, the abi4 mutant demonstrated increased susceptibility to TSSM, reflected as enhanced female fecundity and greater frequency of mite leaf damage after trypan blue staining. Because ABI4 is regarded as an important player in the plastid-to-nucleus retrograde signalling process, we investigated the plastid envelope membrane dynamics using stroma-associated fluorescent marker. Our results indicated a clear increase in the number of stroma-filled tubular structures deriving from the plastid membrane (stromules) in the close proximity of the site of mite leaf damage, highlighting the importance of chloroplast-derived signals in the response to TSSM feeding activity

Усовершенствованная модель взаимодействия пешеходного и поворотного транспортного потоков для определения экономических издержек движения

Selection of the scheme concerning organization of movement of turning transport flows at crossings with traffic light regulation is presently determined by simplified criteria of pedestrian safety without taking into account other traffic expenses. So the existing schemes of regulation often lead to rather high economic and ecological expenses.The paper proposes a model of pedestrian and turn transport flow interaction. This model is modified on the basis of experimental results. In addition to this the paper contains system of dependencies that permits to determine with high accuracy volume of economic and ecological expenses in order to select optimum scheme of the organization of traffic movement at the regulated crossing.Выбор схемы организации движения поворотных транспортных потоков на пересечениях со светофорным регулированием в настоящее время в основном определяется по упрощенному критерию безопасности движения пешеходов без учета других видов издержек движения. В результате применяемые на практике схемы регулирования нередко приводят к повышенному уровню экономических и экологических издержек.В статье предложена модель взаимодействия пешеходного и поворотного транспортного потоков, уточненная на основании результатов экспериментальных исследований, а также система зависимостей, позволяющая с более высокой точностью определить объем экономических и экологических издержек для выбора оптимальной схемы организации дорожного движения на регулируемом пересечении

Особливості морфології молочної залози свійських м’ясоїдних тварин

The mammary gland is a target organ for hormones in the hypothalamus, pituitary gland, thyroid gland, and ovaries. In the postnatal period of animal ontogenesis, breast growth, and development are determined by the estrous cycle and pregnancy. One of the most pressing problems in morphology, mammology, and reproductology of animals is the study of the structure of the breast at the macro and microscopic levels. However, modern studies on the morphology of animals' breasts are mainly devoted to the features of pathomorphological changes in the breast during carcinogenesis. The work aims to conduct a scientific review of the study of normal breast morphology in domestic carnivores. Electronic publication searches have been conducted in the Web of Science, Scopus, PubMed, and Google Scholar databases over the past 20 years. The principles of objectivity and a comprehensive attitude to studying the chosen problem are used. The authors of the review article review the current scientific literature and summarize current knowledge on the features of dog and cat breast morphology. The anatomical structure of the breast of animals is presented with an emphasis on its topography. According to the description of the microscopic structure of the breast, its main structural components are characterized by secretory parts (alveoli and tubes) and intraparticle excretory ducts. Anatomical characteristics of the nerves, blood, and lymphatic vessels of the mammary glands of dogs and cats are presented. Morphological changes in the mammary gland of dogs and cats at different stages of the estrus cycle and during pregnancy are described; in particular, the mammary gland is at rest (inactive) during proestrus and estrus. According to diestrus, due to an increase in progesterone levels, successive morphological changes occur, in particular, stromal and ductal proliferation; early development of lobules with branching ducts and proliferation of alveoli; the dominance of glandular tissue with large lobules containing secretory material; early regression, an increase in interparticle connective tissue, eosinophilic protein secretion in dilated ducts and alveoli. Complete involution of the alveoli and tubes of the breast is recorded at the end of the anestrus. The described anatomical and microscopic features of the structure of the mammary glands of dogs and cats are relevant for the comparative morphology of carnivores at different stages of the sexual cycle and during pregnancy. Data on blood supply, lymphatic drainage, and innervation of the breast are essential for its functional characteristics in normal and pathological conditions, particularly for developing a reasonable model of breast extirpation in malignant tumors.Молочна залоза є органом-мішенню для гормонів гіпоталамуса, гіпофіза, щитоподібної залози і яєчників. У постнатальному періоді онтогенезу тварин ріст та розвиток молочної залози визначається естральним циклом і вагітністю. Однією з актуальних проблем морфології, мамології та репродуктології тварин є вивчення будови молочної залози на макро- і мікроскопічному рівні. Проте сучасні дослідження з морфології молочної залози тварин присвячені в основному особливостям патоморфологічних змін молочної залози за канцерогенезу. Мета роботи – провести науковий огляд з вивчення нормальної морфології молочної залози свійських м’ясоїдних тварин. Електронний пошук публікацій було проведено в базах даних Web of Science, Scopus, PubMed та Google Scholar, переважно за останні 20 років. Використано принципи об’єктивності та комплексного ставлення до вивчення обраної проблеми. Авторами оглядової статті розглянуто сучасну наукову літературу та узагальнено поточні знання з особливостей морфології молочної залози собаки і кішки. Анатомічну будову молочної залози тварин представлено з акцентом на її топографію, за опису мікроскопічної будови молочної залози охарактеризовано її основні структурні компоненти: секреторні відділи (альвеоли і трубки) та внутрішньочасточкові вивідні протоки. Подано анатомічну характеристику нервів, кровоносних і лімфатичних судин молочної залози собаки та кішки. Описано морфологічні зміни в молочній залозі собаки і кішки на різних стадіях естрального циклу і за вагітності, зокрема, що молочна залоза перебуває в стані спокою (неактивна) під час проеструсу і тічки. За діеструсу, внаслідок підвищення рівня прогестерону, відбуваються послідовні морфологічні зміни, зокрема стромальна і протокова проліферація; ранній розвиток часточок з розгалуженням протоків і проліферацією альвеол; домінування залозистої тканини з великими часточками, які містять секреторний матеріал; рання регресія, збільшення міжчасточкової сполучної тканини, еозинофільний білковий секрет в розширених протоках і альвеолах. Повна інволюція альвеол і трубок молочної залози реєструється в кінці анеструса. Описані анатомічні та мікроскопічні особливості будови молочної залози собаки і кішки актуальні для порівняльної морфології м’ясоїдних тварин на різних стадіях статевого циклу і за вагітності. Дані з кровопостачання, лімфодренажу та іннервації молочної залози важливі для її функціональної характеристики в нормі та за патологічних станів, зокрема для розробки обґрунтованої моделі екстирпації молочної залози при злоякісних пухлинах

The effect of GdYVO4:Eu3+ nanocrystals on the intercellular adhesion of mesenchymal stem cells in vitro

Adult stem cells, such as MSCs, spontaneously differentiate in vitro. This makes it difficult both to study this important cell type and to grow large numbers of MSCs for clinical use. While conventional cell cultivation methods cannot cope with this problem, nanostructured materials science offers hope. The effect of small-sized spherical nanoparticles based on orthovanadates of rare-earth elements activated by europium (GdYVO4:Eu3+ nanoparticles, diameter 1–2 nm) on cell-cell adhesion of rat bone marrow mesenchymal stem cells (rBM-MSCs) in vitro was studied using electrophoretic separation of proteins, immunofluorescence and confocal laser scanning microscopy. Our study revealed that rBM-MSCs treated with small-sized GdYVO4:Eu3+ nanoparticles had a significant impairment of intercellular adhesion in vitro. The pre-incubation of mesenchymal stem cells of rat bone marrow with GdYVO4:Eu3+ nanocrystals at a non-toxic concentration of 0.5 µg/mL during 1 hour of cultivation did not lead to significant changes in cell monolayer, the number of cells and the area of cell bodies did not change. However, the density of the monolayer and the area of the cell field decreased after the incubation. The incubation of cells with nanoparticles led to an increase in the area of the intercellular gate – a location of disruption of cell adhesion, compared to cells without nanoparticles in culture medium. The pre-incubation of rBM-MSCs with nanocrystals caused no changes in the content of total cadherins in the plasma membrane; a decrease in the content of cytoplasmic calreticulin and an increase in the content of surface calreticulin; a decrease in the content of free calcium in the cytoplasm, and an increase in protein-bound intercellular calcium and calcium in the extracellular space. The colocalization analysis revealed that the colocalization of calreticulins with cadherins on the outer surface of the plasma membrane of cells significantly increased after the incubation with GdYVO4:Eu3+ nanocrystals. The paper proposes a possible mechanism of reducing the degree of adhesion by nanocrystals. This study emphasizes the possibility of modulating MSCs adhesion using GdYVO4:Eu3+ nanoparticles. The development of new technologies capable of mitigating adhesion is crucial for the development of regenerative strategies using stem cells

Step by step: reconstruction of terrestrial animal movement paths by dead-reckoning

Background: Research on wild animal ecology is increasingly employing GPS telemetry in order to determine animal movement. However, GPS systems record position intermittently, providing no information on latent position or track tortuosity. High frequency GPS have high power requirements, which necessitates large batteries (often effectively precluding their use on small animals) or reduced deployment duration. Dead-reckoning is an alternative approach which has the potential to ‘fill in the gaps’ between less resolute forms of telemetry without incurring the power costs. However, although this method has been used in aquatic environments, no explicit demonstration of terrestrial dead-reckoning has been presented.Results: We perform a simple validation experiment to assess the rate of error accumulation in terrestrial dead-reckoning. In addition, examples of successful implementation of dead-reckoning are given using data from the domestic dog Canus lupus, horse Equus ferus, cow Bos taurus and wild badger Meles meles.Conclusions: This study documents how terrestrial dead-reckoning can be undertaken, describing derivation of heading from tri-axial accelerometer and tri-axial magnetometer data, correction for hard and soft iron distortions on the magnetometer output, and presenting a novel correction procedure to marry dead-reckoned paths to ground-truthed positions. This study is the first explicit demonstration of terrestrial dead-reckoning, which provides a workable method of deriving the paths of animals on a step-by-step scale. The wider implications of this method for the understanding of animal movement ecology are discussed

Spatio-Temporal Gap Analysis of OBIS-SEAMAP Project Data: Assessment and Way Forward

The OBIS-SEAMAP project has acquired and served high-quality marine mammal, seabird, and sea turtle data to the public since its inception in 2002. As data accumulated, spatial and temporal biases resulted and a comprehensive gap analysis was needed in order to assess coverage to direct data acquisition for the OBIS-SEAMAP project and for taxa researchers should true gaps in knowledge exist. All datasets published on OBIS-SEAMAP up to February 2009 were summarized spatially and temporally. Seabirds comprised the greatest number of records, compared to the other two taxa, and most records were from shipboard surveys, compared to the other three platforms. Many of the point observations and polyline tracklines were located in northern and central Atlantic and the northeastern and central-eastern Pacific. The Southern Hemisphere generally had the lowest representation of data, with the least number of records in the southern Atlantic and western Pacific regions. Temporally, records of observations for all taxa were the lowest in fall although the number of animals sighted was lowest in the winter. Oceanographic coverage of observations varied by platform for each taxa, which showed that using two or more platforms represented habitat ranges better than using only one alone. Accessible and published datasets not already incorporated do exist within spatial and temporal gaps identified. Other related open-source data portals also contain data that fill gaps, emphasizing the importance of dedicated data exchange. Temporal and spatial gaps were mostly a result of data acquisition effort, development of regional partnerships and collaborations, and ease of field data collection. Future directions should include fostering partnerships with researchers in the Southern Hemisphere while targeting datasets containing species with limited representation. These results can facilitate prioritizing datasets needed to be represented and for planning research for true gaps in space and time