排序方式: 共有108条查询结果,搜索用时 15 毫秒
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Anastasiya A. Fronya Sergey V. Antonenko Nikita V. Karpov Nikolay S. Pokryshkin Anna S. Eremina Valery G. Yakunin Alexander Yu. Kharin Alexander V. Syuy Valentin S. Volkov Yaroslava Dombrovska Alexander A. Garmash Nikolay I. Kargin Sergey M. Klimentov Victor Yu. Timoshenko Andrei V. Kabashin 《Materials》2022,15(15)
Due to particular physico-chemical characteristics and prominent optical properties, nanostructured germanium (Ge) appears as a promising material for biomedical applications, but its use in biological systems has been limited so far due to the difficulty of preparation of Ge nanostructures in a pure, uncontaminated state. Here, we explored the fabrication of Ge nanoparticles (NPs) using methods of pulsed laser ablation in ambient gas (He or He-N2 mixtures) maintained at low residual pressures (1–5 Torr). We show that the ablated material can be deposited on a substrate (silicon wafer in our case) to form a nanostructured thin film, which can then be ground in ethanol by ultrasound to form a stable suspension of Ge NPs. It was found that these formed NPs have a wide size dispersion, with sizes between a few nm and hundreds of nm, while a subsequent centrifugation step renders possible the selection of one or another NP size fraction. Structural characterization of NPs showed that they are composed of aggregations of Ge crystals, covered by an oxide shell. Solutions of the prepared NPs exhibited largely dominating photoluminescence (PL) around 450 nm, attributed to defects in the germanium oxide shell, while a separated fraction of relatively small (5–10 nm) NPs exhibited a red-shifted PL band around 725 nm under 633 nm excitation, which could be attributed to quantum confinement effects. It was also found that the formed NPs exhibit high absorption in the visible and near-IR spectral ranges and can be strongly heated under photoexcitation in the region of relative tissue transparency, which opens access to phototherapy functionality. Combining imaging and therapy functionalities in the biological transparency window, laser-synthesized Ge NPs present a novel promising object for cancer theranostics. 相似文献
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Anastasiya S. Babkina Irina V. Ostrova Mikhail Ya Yadgarov Artem N. Kuzovlev Andrey V. Grechko Alexey V. Volkov Arkady M. Golubev 《Viruses》2022,14(2)
The increased plasma levels of von Willebrand factor (VWF) in patients with COVID-19 was reported in many studies, and its correlation with disease severity and mortality suggest its important role in the pathogenesis of thrombosis in COVID-19. We performed histological and immunohistochemical studies of the lungs of 29 patients who died from COVID-19. We found a significant increase in the intensity of immunohistochemical reaction for VWF in the pulmonary vascular endothelium when the disease duration was more than 10 days. In the patients who had thrombotic complications, the VWF immunostaining in the pulmonary vascular endothelium was significantly more intense than in nonsurvivors without thrombotic complications. Duration of disease and thrombotic complications were found to be independent predictors of increased VWF immunostaining in the endothelium of pulmonary vessels. We also revealed that bacterial pneumonia was associated with increased VWF staining intensity in pulmonary arterial, arteriolar, and venular endothelium, while lung ventilation was an independent predictor of increased VWF immunostaining in arterial endothelium. The results of the study demonstrated an important role of endothelial VWF in the pathogenesis of thrombus formation in COVID-19. 相似文献
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Translational validity of PASAT and the effect of fatigue and mood in patients with relapsing remitting MS: A functional MRI study 下载免费PDF全文
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An extensive tumor array analysis supports tumor suppressive role for nucleophosmin in breast cancer
Karhemo PR Rivinoja A Lundin J Hyvönen M Chernenko A Lammi J Sihto H Lundin M Heikkilä P Joensuu H Bono P Laakkonen P 《The American journal of pathology》2011,179(2):1004-1014
Nucleophosmin (NPM) is a multifunctional protein involved in a complex network of interactions. The role of NPM in oncogenesis is controversial. The NPM gene (NPM1) is mutated or rearranged in a number of hematological disorders, but such changes have not been detected in solid cancers. However, experiments with cultured NPM-null cells and with mice carrying a single inactivated NPM allele indicate a tumor suppressor function for NPM. To resolve the role of NPM in solid cancers, we examined its expression and localization in histologically normal breast tissue and a large array of human breast carcinoma samples (n = 1160), and also evaluated its association with clinicopathological variables and patient survival. The intensity and localization (nucleolar, nuclear, cytoplasmic) of NPM varied across clinical samples. No mutations explaining the differences were found, but the present findings indicate that expression levels of NPM affected its localization. Our study also revealed a novel granular staining pattern for NPM, which was an independent prognostic factor of poor prognosis. In addition, reduced levels of NPM protein were associated with poor prognosis. Furthermore, luminal epithelial cells of histologically normal breast displayed high levels of NPM and overexpression of NPM in the invasive MDA-MB-231 cells abrogated their growth in soft agar. These results support a tumor suppressive role for NPM in breast cancer. 相似文献
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Attems J Quass M Gartner W Nabokikh A Wagner L Steurer S Arbes S Lintner F Jellinger K 《Experimental gerontology》2007,42(3):215-222
Disturbed calcium homeostasis plays a crucial role in the aetiology of Alzheimer's disease (AD) and the aging process. We evaluated immunoreactivity of secretagogin, a recently cloned calcium binding protein, in hippocampus and adjacent entorhinal cortex of 30 neuropathologically examined post mortem brains (m:f=12:18; mean age, 79.8+/-15.1 years). The study group consisted of 15 cases fulfilling the criteria for high probability of AD according to the NIA-Reagan Institute Criteria and 15 cases with no to medium probability. Sections were incubated with secretagogin-specific antibodies and the number of immunoreactive neurons as well as staining intensities in both neurons and neuropil were assessed. Both cellular and neuropil immunoreactivity were restricted to subiculum and Ammons horn. Cellular immunoreactivity was further restricted to pyramidal neurons and showed a hierarchical distribution: the mean percentage of immunoreactive neurons was highest in sector CA3 (64.41%), followed by CA2 (44.09%), CA4 (34.38%), CA1 (10.9%), and the subiculum (2.92%; P<0.001, except CA2-CA4, P>0.05), while it did not differ significantly between groups with different degrees of AD pathology. The pattern of secretagogin immunoreactivity resembles that of calcium sensor proteins as it is restricted to a subset of neurons and therefore secretagogin could serve highly specialized tasks in neuronal calcium signalling. 相似文献
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Arutiunian Vardan Lopukhina Anastasiya Minnigulova Alina Shlyakhova Anastasia Davydova Elizaveta Pereverzeva Darya Sorokin Alexander Tyushkevich Svetlana Mamokhina Uliana Danilina Kamilla Dragoy Olga 《Journal of autism and developmental disorders》2022,52(2):584-599
Journal of Autism and Developmental Disorders - The purpose of the present research was to comprehensively assess the language abilities of Russian primary-school-aged children with Autism Spectrum... 相似文献