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171.
Che Mat Mohd Firdaus Mohamad Hanif Ezanee Azlina Abdul Murad Nor Azian Ibrahim Kamariah Harun Roslan Jamal Rahman 《Molecular biology reports》2021,48(2):1493-1503
Molecular Biology Reports - Despite the advancements in primary brain tumour diagnoses and treatments, the mortality rate remains high, particularly in glioblastoma (GBM). Chemoresistance,... 相似文献
172.
Farag Ola M. Abd-Elsalam Reham M. Ogaly Hanan A. Ali Sara E. El Badawy Shymaa A. Alsherbiny Muhammed A. Li Chun Guang Ahmed Kawkab A. 《Neurochemical research》2021,46(4):819-842
Neurochemical Research - Acrylamide (ACR) is an environmental pollutant with well-demonstrated neurotoxic and neurodegenerative effects in both humans and experimental animals. The present study... 相似文献
173.
174.
Anna Juras Edvard Ehler Maciej Chyleński Łukasz Pospieszny Anna Elżbieta Spinek Helena Malmström Maja Krzewińska Krzysztof Szostek Wojciech Pasterkiewicz Marek Florek Stanisław Wilk Barbara Mnich Janusz Kruk Marzena Szmyt Sławomir Kozieł Anders Götherström Mattias Jakobsson Miroslawa Dabert 《American journal of physical anthropology》2021,176(2):223-236
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176.
Shirin Saberianpour Mohamad Hadi Saeed modaghegh Hamidreza Rahimi Mohammad Mahdi Kamyar 《Biophysical reviews》2021,13(1):139
Varicose veins are the most common vascular disease in humans. Veins have valves that help the blood return gradually to the heart without leaking blood. When these valves become weak, blood and fluid collect and pool by pressing against the walls of the veins, causing varicose veins. In the cardiovascular system, mechanical forces are important determinants of vascular homeostasis and pathological processes. Blood vessels are constantly exposed to a variety of hemodynamic forces, including shear stress and environmental strains caused by the blood flow. In varicose veins within the leg, venous blood pressure rises in the vein of the lower extremities due to prolonged standing, creating a peripheral tension in the vessel wall thereby causing mechanical stimulation of endothelial cells and vascular smooth muscle. Studies have shown that long-term increased exposure to vascular wall tension is associated with the overexpression of HIF-1α and HIF-2α and increased levels of MMP-2 and MMP-9, thereby reducing venous contraction and progressive venous dilatation, which is involved in the development of varicose veins. Following the expression of metalloproteinase, the expression of type 1 collagen increases, and the amount of type 3 collagen decreases. Therefore, collagen imbalance will cause the varicose veins to not stretch. Loss of structural proteins (type 3 collagen and elastin) in the vessel wall causes the loss of the biophysical properties of the varicose vein wall. This review article tries to elaborate on the effect of mechanical forces and sensors of these forces on the vascular wall in creating the mechanism of mechanosignaling, as well as the role of the onset of molecular signaling cascades in the pathology of varicose veins. 相似文献
177.
Arnaud Huguet Sylvain Bernard Rime El Khatib Martina I. Gocke Guido L. B. Wiesenberg Sylvie Derenne 《Geobiology》2021,19(1):75-86
Rhizoliths, that is, roots fossilized by secondary carbonates, have been known for ages and are increasingly used for paleoenvironmental reconstructions. However, knowledge about their formation mechanisms remains limited. This study reports the mineralogical and chemical characterization of rhizoliths at different stages of mineralization and fossilization in the Late Pleistocene loess–paleosol sequence of Nussloch (SW Germany). Scanning electron microscopy coupled with elemental mapping and 13C solid‐state nuclear magnetic resonance were used to concomitantly characterize the mineral and organic matter of the rhizoliths. These joint analyses showed for the first time that large rhizoliths are not necessarily remains of single large roots but consist of numerous microrhizoliths as remains of fine roots, formed mainly by calcium carbonates with only low amounts of Mg and Si. They further revealed that the precipitation of secondary carbonates occurs not only around, but also within the plant root and that fossilization leads to the selective preservation of recalcitrant root biopolymers—lignin and suberin. The precipitation of secondary carbonates was observed to occur first around fine roots, the epidermis acting as a first barrier, and then within the root, within the cortex cells, and even sometimes around the phloem and within the xylem. This study suggests that the calcification of plant roots starts during the lifetime of the plant and continues after its death. This has to be systematically investigated to understand the stratigraphic context before using (micro)rhizoliths for paleoenvironmental reconstructions in terrestrial sediments. 相似文献
178.
Chorong Park Chen Peng M. Julhasur Rahman Sherry L. Haller Loubna Tazi Greg Brennan Stefan Rothenburg 《PLoS pathogens》2021,17(1)
The antiviral protein kinase R (PKR) is an important host restriction factor, which poxviruses must overcome to productively infect host cells. To inhibit PKR, many poxviruses encode a pseudosubstrate mimic of the alpha subunit of eukaryotic translation initiation factor 2 (eIF2), designated K3 in vaccinia virus. Although the interaction between PKR and eIF2α is highly conserved, some K3 orthologs from host-restricted poxviruses were previously shown to inhibit PKR in a species-specific manner. To better define this host range function, we compared the sensitivity of PKR from 17 mammals to inhibition by K3 orthologs from closely related orthopoxviruses, a genus with a generally broader host range. The K3 orthologs showed species-specific inhibition of PKR and exhibited three distinct inhibition profiles. In some cases, PKR from closely related species showed dramatic differences in their sensitivity to K3 orthologs. Vaccinia virus expressing the camelpox virus K3 ortholog replicated more than three orders of magnitude better in human and sheep cells than a virus expressing vaccinia virus K3, but both viruses replicated comparably well in cow cells. Strikingly, in site-directed mutagenesis experiments between the variola virus and camelpox virus K3 orthologs, we found that different amino acid combinations were necessary to mediate improved or diminished inhibition of PKR derived from different host species. Because there is likely a limited number of possible variations in PKR that affect K3-interactions but still maintain PKR/eIF2α interactions, it is possible that by chance PKR from some potential new hosts may be susceptible to K3-mediated inhibition from a virus it has never previously encountered. We conclude that neither the sensitivity of host proteins to virus inhibition nor the effectiveness of viral immune antagonists can be inferred from their phylogenetic relatedness but must be experimentally determined. 相似文献
179.
Rahman Md. Mokhlesur Jahan Hawa Rabbe Md. Fazle Chakraborty Moumita Salauddin Md. 《EcoHealth》2021,18(1):31-43
EcoHealth - Global amphibian populations are facing a novel threat, chytridiomycosis, caused by the fungus Batrachochytrium dendrobatidis (Bd), which is responsible for the severe decline of a... 相似文献
180.
Darvishi Vahid Darvishi Saeed Bahrami-Bavani Marziyeh Navidbakhsh Mahdi Asiaei Sasan 《Biomechanics and modeling in mechanobiology》2021,20(5):1809-1817
Biomechanics and Modeling in Mechanobiology - Coronavirus and its spread all over the world have been the most challenging crisis in 2020. Hospitals are categorized among the most vulnerable... 相似文献