birch bark
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2021 ◽  
Vol 15 (4) ◽  
pp. 668-682
Author(s):  
Nadezhda Anatolievna x Nadezhda Anatolievna Leshchinskaya

The paper introduces into scientific discourse materials of the sacrificial complex, unique in its content, recovered from burial 33 of the 6-8 cen. Tat-Boyary cemetery. The site correlates with the early medieval formation of the western part of the Ancient Perm oecumene in the Kama-Volga Interfluve, and from the archaeological perspective - with the Emanaevo culture. The sacrificial complex is a birch bark box with a number of artifacts that was located in a special niche of the cenotaph. The paper gives a detailed description of the sacrificial complex consisting of bronze and silver elements of the detachable pectoral plate, belt, set of pectoral decorations, and the wallet, as well as fabric and leather elements of the female ceremonial costume. A wide range of parallels quoted in the paper allows to date the complex to the 8 or, possibly, the early 9century and to justify the high-scale involvement of the Vyatka population into the ethnocultural and trade Eurasian long- and close-distance contacts. They demonstrate the most stable contacts with the Volga-Finnish world and Ancient Perm cultures of the Cheptsa and Kama basins. Being introduced into scientific discourse, the materials of the Tat-Boyary sacrificial complex enhance our insight into the cultural specifics of the Vyatka population in the Middle Ages; besides, they are important to a better understanding of archaeological origin of the Kama-Vyatka Interfluve local ethnographic costumes.


Plants ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 2663
Author(s):  
Hardeep Singh Tuli ◽  
Katrin Sak ◽  
Dhruv Sanjay Gupta ◽  
Ginpreet Kaur ◽  
Diwakar Aggarwal ◽  
...  

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.


Author(s):  
Al'bert Tagirovich Akhatov

The subject of this research is the woodworking tools of the Bashkirs in in the XVII– XVIII centuries. The goal lies in examination of the tools used by the Bashkirs for wood processing during the XVII – XVIII centuries leaning on the archaeological materials obtained in the course of exploration of Aznayevo settlement and Berekovo rural localities. The article also involves the written record of the authors of the late XVIII sources and the data of historical-ethnographic researcher of later periods. The research relies in the comprehensive approach of the available archaeological, written and ethnographic materials; as well as descriptive, historical-comparative methods, and analysis of real sources. This article is first to examine the woodworking tools used by the Bashkirs in XVII – XVIII centuries. The archaeological collections allows establishing that the Bashkirs used axes, knives, scraper, graver and drill for wood processing. For basket weaving from bast and birch bark was used the curved awl. According to the written sources, the woodworking tools also included adzes and chisels. The explored archaeological and written materials allow concluding that the woodworking tools of the XVII – XVIII centuries continued to exist among the Bashkir population until the XIX – early XXI centuries, which is proven by the results of historical-ethnographic research.


2021 ◽  
Vol 12 (5) ◽  
pp. 6873-6894

Betulin dipropionate is a natural compound with high cytotoxicity toward many cancer cells. The one-step synthesis directly from the birch bark without a separate betulin isolation stage was developed to obtain betulin dipropionate. Due to its composition, betulin dipropionate is a promising drug for treating a wide range of diseases. However, the poor water solubility of this compound has limited its applications. We prepared the composites of betulin dipropionate using two methods: ball milling of the mixtures of betulin dipropionate with synthetic and natural polymers, such as polyvinylpyrrolidone polyethylene glycol, fumed silica, arabinogalactan, and preparation of thin films with arabinogalactan by evaporating the aqueous solutions. These composites showed higher water solubility and improved antitumor properties against ascites carcinoma cells and human lung adenocarcinoma cells compared with the initial substance. Furthermore, the cell viability studies based on Annexin V and Propidium iodide probes confirmed the high proapoptotic effect of betulin dipropionate against cancer cells.


REPORTS ◽  
2021 ◽  
Vol 5 (339) ◽  
pp. 182-188
Author(s):  
А.T. Takibayeva ◽  
R.Z. Kassenov ◽  
О.V. Demets ◽  
M.R. Aliyeva ◽  
А.А. Bakibayev

2021 ◽  
Author(s):  
D. Abdullina ◽  
K. Valeev ◽  
R. Safin

As know, all wood material is recycled only half, and the rest of it remains unused. In practice, wood waste is most often plowed or burned, at a time when such wood is a valuable natural raw material that can compensate for the needs of a number of sectors of the economy. In this regard, the problem of recycling waste from the woodworking industry is very relevant today. Wood waste contains a large amount of substances capable of exhibiting biological activity. In particular, such biologically active substances include betulin, which is found in birch bark, which, due to its many advantages, has found wide application in medical, perfumery, cosmetic, food and other industries. For the rational use of wood and wood materials, it is necessary to develop new technologies and equipment for processing wood into products that are in demand for mankind. The paper provides an overview of the processing of birch bark. The relevance and prospects of birch species as a raw material for the chemical industry have been established. An installation for obtaining biologically active substances from wood waste is presented.


2021 ◽  
Vol 12 ◽  
Author(s):  
Chenghao Ren ◽  
Jie Jin ◽  
Wei Hu ◽  
Qi Chen ◽  
Jian Yang ◽  
...  

Osteoarthritis (OA) is a common degenerative joint disease featuring the degeneration, destruction, and ossification of cartilage. Inflammation which may facilitate OA occurrence and development is considered as the main pathological factor. Betulin, a natural product extracted from birch bark, has been commonly used for inflammation treatment; however, its role in OA remains unclear. This study is aimed to explore whether betulin can suppress IL-1β–induced inflammation in chondrocytes and alleviate OA in vitro and in vivo. In in vitro studies, the generation of pro-inflammatory factors, such as interleukin-6 (IL-6), tumor necrosis factor alpha (TNF-α), prostaglandin E2 (PGE2), and nitric oxide (NO), was assessed using the enzyme-linked immunosorbent assay (ELISA) and Griess reaction. As revealed by results, betulin inhibited the expression of pro-inflammatory mediators. In addition, the protein expressions of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), matrix metalloproteinase (MMP-13), thrombospondin motifs 5 (ADAMTS5), Collagen II, and Aggrecan were quantified using Western blot analysis. We found that betulin could inhibit the generation of COX-2 and iNOS induced by IL-1β, indicating that betulin has anti-inflammatory effects in chondrocytes. Furthermore, betulin downregulates the expression of MMP-13 and ADAMTS-5 and upregulates the expression of Collagen II and Aggrecan, indicating that it can inhibit the degradation of the extracellular matrix. In mechanism, betulin activated the AKT/Nrf2 pathway and inhibited the phosphorylation of p65. In in vivo studies, administration of betulin in vivo could inhibit cartilage destruction and inflammatory progression. Therefore, these findings suggest that betulin may alleviate IL-1β–induced OA via the AKT/Nrf2/HO-1/NF-κB signal axis, and betulin may be a potential drug for the treatment of OA.


Author(s):  
Ruzil R. Sattarov ◽  
◽  
Elvir V. Kamaleev ◽  
◽  

The article introduces into scientific discourse the materials of the burial 15 of the Trikolsky burial ground studied in 1978 by V.A. Ivanov. This burial featured finds unique for the entire Pyany Bor culture – a glass bowl and a cassolette. The burial also contained beads made of single-color and multi-colored glass and glass with a metal inlay, pendants made of adult moose incisors, bronze plaques, openwork overlays, temple pendants, etc. The authors concluded that the unique items came to the Pyany Bor population as a result of contacts with Sarmatian nomads in the 1st century AD. In addition, the study presents data on the manufacturing material of certain items obtained using natural scientific methods. It was determined that the cassolette was made of a sedimentary rock – argillite. Metal items, except a leaf-shaped pendant made of precious metal, are made of tin bronze. A “gum” sample discovered next to a glass bowl contains matter of vegetable origin. Its components are betulinic and tricyclic acids contained in birch bark and conifer resin (oleoresin), respectively.


2021 ◽  
Vol 22 (19) ◽  
pp. 10228
Author(s):  
Agnieszka Richert ◽  
Agnieszka Kalwasińska ◽  
Maria Swiontek Brzezinska ◽  
Grażyna B. Dąbrowska

The microbial biodegradation of new PLA and PCL materials containing birch tar (1–10% v/v) was investigated. Product of dry distillation of birch bark (Betula pendula Roth) was added to polymeric materials to obtain films with antimicrobial properties. The subject of the study was the course of enzymatic degradation of a biodegradable polymer with antibacterial properties. The results show that the type of the material, tar concentration, and the environment influenced the hydrolytic activity of potential biofilm degraders. In the presence of PCL films, the enzyme activities were higher (except for α-D-glucosidase) compared to PLA films. The highest concentration of birch tar (10% v/v) decreased the activity of hydrolases produced by microorganisms to the most significant extent; however, SEM analysis showed the presence of a biofilm even on plastics with the highest tar content. Based on the results of the biological oxygen demand (BOD), the new materials can be classified as biodegradable but, the biodegradation process was less efficient when compared to plastics without the addition of birch tar.


2021 ◽  
Vol 11 (18) ◽  
pp. 8721
Author(s):  
Johanna Klügl ◽  
Giovanna Di Pietro

In this paper we present an atlas of micromorphological degradation of archaeological birch bark for the first time. We analysed the morphology of 13 samples extracted from ice-logged, waterlogged and cave-retrieved objects dated from the Neolithic to the Middle Age by means of light microscopy (LM) and transmission electron microscopy (TEM). We then compared their morphology to that of a contemporary sample, both intact and decayed. In all samples, 13 morphological characteristics that can be associated with fungal, bacterial, chemical, mechanical and light degradation are defined and described, and example LM and TEM images are provided. This novel atlas provides conservator-restorers a much-needed tool to relate the macroscopic appearance to the microscopic structure of birch bark objects. The most important macroscopic features allowing estimation of the state of preservation at the cell level are colour changes, loss of pliability, presence of delamination and increased brittleness. Colour change and delamination can be connected to microscopic features, and microscopic analysis can trace whether they were caused by biotic, chemical or physical decay. However, increased brittleness cannot be connected to a specific microscopic feature.


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