Репозиторий Университета

© 2018 IEEE. We demonstrate a wavelet-domain denoising technique for imaging of human brain malignant tissues by optical coherence tomography. It allows for reducing the scattering noise and retaining signal artifacts for each tissue type, including malignant glioma and meningioma.

© 2018 IEEE. In our work, we have performed in vitro terahertz (THz) measurements of gelatin-embedded malignant human brain gliomas using the THz pulsed spectroscopy. The gelatin embedding yields sustain the THz response of tissues close to that of the freshly-excised ones for a long time after the resection. We have observed significant differences between the THz responses of normal and pathological tissues of the brain, which highlights a potential of the THz technology in label-free intraoperative neurodiagnosis of tumors.

© 2018 IEEE. Modern progress in terahertz (THz) diagnostics of malignancies, including non-invasive, least-invasive and intraoperative techniques is briefly discussed. Special attention is paid to intraoperative diagnosis of brain tumors, which is a rapidly developing field nowadays. We discuss our recent results in this research field, which are associated with (i) in vitro studies the THz dielectric response of gelatin-embedded human brain tumors (including gliomas and meningiomas featuring different grades), (ii) analysis an ability for differentiation between normal and pathological tissues of the brain relying on the methods of THz spectroscopy and imaging, and, finally, (iii) development of novel THz instrumentation for the intraoperative detection of margins of tumors in order to guarantee its gross total resection.

© 2018 Elsevier B.V. Over the last decade, autophagy has emerged as one of the critical cellular systems that control homeostasis. Besides management of normal homeostatic processes, autophagy can also be induced by tissue damage stress or by rapidly progressing tumors. During tumor progression, autophagy mediates a cellular reaction to the changes inside and outside of cells, which leads to tumor adaptation. Even though the regulation of autophagy seems universal and is a well-described process, its dysregulation and role in glioma progression remain an important topic of investigation. In this review, we summarize recent evidence of autophagy regulation in brain tumor tissues and possible interconnection between signaling pathways that govern cellular responses. This perspective may help to assess the qualitative differences and various outcomes in response to autophagy stimulation.

© 2018, Media Sphera Publishing Group. All rights reserved. Inflammasomes are macromolecular complexes that contain many copies of receptors recognizing molecular patterns of pathogenic agents (PAMP) and damage-associated structures (DAMP), and also include molecules of adapter protein ASC and procaspase- 1. Activation of inflammasomes leads to the formation of active caspase-1 that, in turn, provides the maturation of pro-IL-1β and pro-IL-18 to IL-1β and IL-18. The latter cytokines play an important role in control of neuroinlfammation in the central nervous system contributing to the pathogenesis of a series of neurological, neurodegenerative and mental disorders. The review discusses the involvement of NLRP3 inflammasome and other their types in the development of the traumatic brain injury, ischemic and hemorrhagic stroke, brain tumors, CNS infections, Alzheimer’s and Parkinson’s diseases, epilepsy, amyotrophic lateral sclerosis, depressiver, and consequences of alcohol abuse. The elucidation of molecular mechanisms and signaling pathways controlled by inflammasomes will allow the development of new therapeutic measures for diseases, in which neuroinflammation plays a leading pathogenetic role.

© 2018 SPIE. We have proposed a wavelet-domain de-noising technique for imaging of human brain malignant glioma by optical coherence tomography (OCT). It implies OCT image decomposition using the direct fast wavelet transform, thresholding of the obtained wavelet spectrum and further inverse fast wavelet transform for image reconstruction. By selecting both wavelet basis and thresholding procedure, we have found an optimal wavelet filter, which application improves differentiation of the considered brain tissue classes-i.e. malignant glioma and normal/intact tissue. Namely, it allows reducing the scattering noise in the OCT images and retaining signal decrement for each tissue class. Therefore, the observed results reveals the wavelet-domain de-noising as a prospective tool for improved characterization of biological tissue using the OCT.

© COPYRIGHT SPIE. Downloading of the abstract is permitted for personal use only. We have performed the in vitro terahertz (THz) spectroscopy of human brain tumors. In order to fix tissues for the THz measurements, we have applied the gelatin embedding. It allows for preserving tissues from hydration/dehydration and sustaining their THz response similar to that of the freshly-excised tissues for a long time after resection. We have assembled an experimental setup for the reflection-mode measurements of human brain tissues based on the THz pulsed spectrometer. We have used this setup to study in vitro the refractive index and the amplitude absorption coefficient of 2 samples of malignant glioma (grade IV), 1 sample of meningioma (grade I), and samples of intact tissues. We have observed significant differences between the THz responses of normal and pathological tissues of the brain. The results of this paper highlight the potential of the THz technology in the intraoperative neurodiagnosis of tumors relying on the endogenous labels of tumorous tissues.