Anti-Inflammatory and Anticancer Properties of Birch Bark-Derived Betulin: Recent Developments

Birch tree bark-derived betulin has attracted scientific interest already for several centuries, being one of the first natural products identified from plants. However, the cellular events regulated by betulin and precise molecular mechanisms under these processes have been begun to be understood only recently. Today, we know that betulin can exert important anticancer activities through modulation of diverse cellular pathways. In this review article, betulin-regulated molecular signaling is unraveled and presented with a special focus on its participation in anti-inflammatory processes, especially by modulating nuclear factor-κB (NF-κB), prostaglandin/COX, and nuclear factor erythroid2-related factor 2 (Nrf2)-mediated cascades. By regulating these diverse pathways, betulin can not only affect the development and progression of different cancers, but also enhance the antitumor action of traditional therapeutic modalities. It is expected that by overcoming the low bioavailability of betulin by encapsulating it into nanocarriers, this promising natural compound may provide novel possibilities for targeting inflammation-related cancers.

Interrelations of Wood Physical and Mechanical Properties and Patterns of Their Change within the Birch Stem

The physical and mechanical properties of standing wood are not constant along the tree height and diameter. They also differ depending on the tree species and conditions of its growth. So, the research purpose is to identify patterns of change and interrelations between the parameters of density, compressive strength and sound propagation velocity along the wood fibers inside the stem of a birch tree growing in the forests of the Middle Volga region of Russia, where such research had never been conducted before. The work was carried out on two sampling areas laid out by standard methods in birch forests of natural origin with average productive capacity on the territory of the Scientific-Experimental Forest District of the Volga State University of Technology in the Mari El Republic. The average age of the birch trees is about 70 yrs, breast height diameter is 30 cm, and height is 28.5 m; 14 sample trees were studied; 0.5 m long chucks were cut out from their stems at a height of 1.3 m from the butt end and at relative heights of 0.25H, 0.5H, and 0.75H. Experimental work was carried out in a laboratory environment with modern technical facilities using standard procedures. Mathematical models describing the changes in the parameters stated above and the interrelations between them with regard to the stem diameter at relative heights were obtained. The research results generally confirmed the findings of other researchers on densitograms and other physical and mechanical properties of wood within the tree stem. However, the features listed above were revealed for birch trees growing under such conditions; in particular, it concerns the ratio of strength and density, as well as the wood strength and the velocity of sound propagation through the fibers. The results obtained have both scientific and practical value as a basis for the development of a non-destructive method for predicting technical properties of standing wood as well as timber for producing assortments for special purposes. For citation: Fedyukov V.I., Chernov V.Yu., Chernova M.S., Tsoy O.V. Interrelations of Wood Physical and Mechanical Properties and Patterns of Their Change within the Birch Stem. Lesnoy Zhurnal [Russian Forestry Journal], 2021, no. 6, pp. 150–159. DOI: 10.37482/0536-1036-2021-6-150-159

A PILOT STUDY OF SENSITIZATION TO PLANE TREE POLLEN IN SOFIA, BULGARIA

Purpose: Platanus pollen is a serious cause of asthma, allergic rhinitis and conjunctivitis in many European countries. The aim of the present pilot study is to investigate the sensitization to 3 different plane tree species in a group of patients with pollinosis. Materials and methods: 21 patients were surveyed - 11 men and 10 women. A skin prick test was performed with a set of allergens: Grass pollen mix; Betulaceae pollen mix; Platanusorientalis; Platanusacerifolia; Platanusoccidentalis. Results: 95% of patients are sensitized to grass pollen, with moderate positive skin reactions predominating. 86% have a co-sensitization to tree pollens also, particularly to the birch tree family. Only 3 (14%) of the studied patients showed slight positive skin tests to the studied plane tree allergens, with no significant difference in sensitization to studied Platanus species (p>0,05). Conclusion: At present, the sensitization to different Platanus species is not comparable to that of grass or birch pollen. However, it will be necessary to conduct new long-term, large-scale studies to prove whether Platanus pose a real threat to people in urban areas. The results of this interdisciplinary study are important both for clinical allergologists and for landscape architects and ecologists involved in the planning and management of urban green infrastructure.

Relation of influencing variables and weather conditions on rainfall partitioning by birch and pine trees

General weather conditions may have a strong influence on the individual elements of the hydrological cycle, an important part of which is rainfall interception. The influence of general weather conditions on this process was analysed, evaluating separately the influence of various variables on throughfall, stemflow, and rainfall interception for a wet (2014), a dry (2015), and an average (2016) year. The analysed data were measured for the case of birch and pine trees at a study site in the city of Ljubljana, Slovenia. The relationship between the components of rainfall partitioning and the influential variables for the selected years was estimated using two statistical models, namely boosted regression trees and random forest. The results of both implemented models complemented each other well, as both indicated the rainfall amount and the number of raindrops as the most influential variables. During the wet year 2014 rainfall duration seems to play an important role, correlating with the previously observed influence of the variables during the wetter leafless period. Similarly, during the dry year 2015, rainfall intensity had a significant influence on rainfall partitioning by the birch tree, again corresponding to the influences observed during the drier leafed period.

Mythopoetic image of silver in the philosophical lyrics of Zoya Dudina

Within the framework of studying the poetics of modern Mari philosophical poetry, this article analyzes the mythopoetic image of silver in the lyrics of Zoya Dudina. Based on the compilation of poems “Kuanyshym, Kuem Ondal...” (joyful to hug a birch tree… (2012), the author determines the semantics and article functions of this image, which represents the philosophical view and perception of the world of the poetess that in a certain way characterizes the lyrical heroine. From such perspective, the lyrics of Zoya Dudina is examines for the first time. The research methodology employs structural-semantic analysis of the literary works, which allowed describing the structural-semantic aspects the image of silver, revealing the authorial concept of the world and man, as well as the character of the lyrical heroine. It is proven that the Mari poetess Zoya Dudina consistently refers to the image of silver in her lyrics. For the poetess, silver is not a precious metal, which attracts people as jewelry, it is a mythopoetic image, the semantics of which is interrelated with the traditional (pagan) culture of the Mari people. Most of the time, this image is depicted within the structure of the natural picture, and reflects the view and perception of the lyrical heroine; it impersonates natural purity, nobility, faithful love, strong friendship, good intentions, unity the of man, nature, and the traditions. It is also underlined that in the mythological context for the lyrical heroine, silver can even resemble the mood.

A case of lymphocytic esophagitis in a woman with multiple allergies

Background Lymphocytic esophagitis is a newly recognized entity of unknown origin. Dysphagia is defined as difficulty swallowing and represents a common symptom in the general population with a prevalence of approximately 20%. Chronic inflammation of the esophageal wall may manifest itself clinically and endoscopically, mimicking inflammation of another origin. However, little is known about the pathogenesis of the disease, as patients are seldom suspected and rarely diagnosed with lymphocytic esophagitis. Case presentation Here, we present a rare case of lymphocytic esophagitis in a patient with multiple allergies and suspected eosinophilic esophagitis. A 28-year-old woman with polyvalent sensitization to food and inhalant allergens presented with intermittent dysphagia, a sensation of a foreign body in the throat, itchiness of the oral cavity after ingesting certain foods, heartburn, and prolonged chewing time. A skin prick test showed positive results for birch-tree, alder, hazel, and rye pollen, as well as house dust mites. Apart from obesity (BMI 30 kg/m2), multiple pustules and excoriations on the skin, her physical examination was insignificant. Esophagogastroduodenoscopy (EGD) was performed revealing full-length but discrete trachealization of the esophagus. A barium swallow test showed slowing of esophageal peristalsis in the recumbent position. No esophageal pathology was observed. A histopathological analysis of mucosal samples revealed slight hyperplasia of the basal layer of the esophagus, and the stomach showed changes typical of chronic gastritis. Conclusions In summary, this clinical case illustrates that lymphocytic esophagitis, as a newly recognized entity, should be considered in the differential diagnosis of chronic dysphagia. Additionally, when treating allergic patients, clinicians should be aware that lymphocytic esophagitis, distinct from eosinophilic esophagitis, should be considered in the diagnosis of patients with atopy and upper gastrointestinal symptoms.

How Characteristics of a Rainfall Event and the Meteorological Conditions Determine the Development of Stemflow: A Case Study of a Birch Tree

The process of rainfall partitioning is usually addressed by three components: rainfall interception, throughfall and stemflow. The occurrence and proportion of stemflow depends on many complexly interconnected factors. To contribute to the interpretation of these interdependencies, the influence of rainfall event characteristics and phenoseasons on stemflow development was analyzed with a new approach. In this study we have focused on the development of stemflow during 156 rainfall events with complete time series records for a single birch tree (Betula pendula Roth.) at a study plot in the city of Ljubljana, Slovenia. For each one of the selected events, diagrams of rainfall and stemflow development during the event were prepared and grouped according to their visual similarities using hierarchical clustering. Additionally, significant meteorological characteristics were determined for each group of events. Four characteristic types of stemflow response were identified and connected to the corresponding event characteristics. Events showing negligible stemflow response to rainfall increase were characterized with rainfall amounts lower than 5 mm, high rainfall intensities, and occurrence in the leafed phenophase. A slow stemflow increase, independent of the increase of the rainfall volume in the open, was recognized for rainfall events delivering less than 20 mm of rainfall during a 5-h duration on average. The majority of these events were observed in the leafed phenophase, corresponding to higher air temperature and vapor pressure deficit. The occurrence of stemflow events, whose development followed the increase of the rainfall amount, was not dependent on the phenophase. However, during these events the average air temperature and vapor pressure deficit were lower, the rainfall amount was larger and the rainfall duration longer in comparison to the events showing independent increase with rainfall. The fourth type of response of stemflow was defined by a strong stemflow response in connection to large rainfall amounts and the longest rainfall duration, as observed for events in the leafless period. The four characteristic types of stemflow response provide additional information on the possible proportion of the rainfall reaching the ground as stemflow.

Of bees, birds, trees, and women: iconography, superstition and victimization of female characters in Yugoslav New Film

This study investigates how the directors of two selected case study films criticise the real-life remnants of patriarchy in the family sphere, in nominally gender-equal Yugoslavia. I argue that they do this by transposing their stories from socialist Yugoslavia to the pre-socialist times: during Ottoman rule and monarchist Yugoslavia. The selected period films Breza/The Birch Tree (Ante Babaja, 1967, Yugoslavia) and Roj/The Beehive aka The Swarm (Miodrag ‘Mića’ Popović, 1966, Yugoslavia), both belonging to the Yugoslav novi film (New Film) movement (1961-1972), refract the workings of the vestiges of patriarchy in a family domain of Yugoslav socialist society. In these two costume dramas, patriarchy is portrayed to its fullest extent, due to their stories being set in the past, ostensibly unrelated to contemporary Yugoslav society and thus uninhibited by the drive to cater to the official discourse of female emancipation. Applying a critical film feminist perspective, by formal analysis via close readings of these two selected films, this article examines the iconography linked to fictional depictions of heroines and delves into the representation of victimisation of women. I investigate whether the depiction of the female sorceress(es) embody the primitiveness, ignorance, and/or poverty of economically disadvantaged and historically oppressed pre-socialist village. In order to peruse not only the individual portrayal of female protagonists but the dynamics of their interaction, the Bechdel test is applied and complemented with concepts such as the ‘reversed masquerade’ and ‘cryptomatriarchy’, which sheds light on the relationship between women and the presence or absence of female solidarity.