Raman study of decomposition of Na-bearing carbonates in water fluid at high P-T parameters.

The study of Na-carbonates stability and their transformations in aqueous carbonate fluid under high P-T conditions is relevant from the point of view of the understanding geochemical processes of the Na-assisted carbon circulation in the Earth's crust and subduction zones. In situ Raman study of Na-bearing carbonate-water-Fe-metal system in diamond anvil cell (DAC) at high P-T conditions revealed that carbonates decompose with abiogenic formation of formates and other organic compounds that differs from behavior of carbonates in dry system. XRD and FTIR methods have been used additionally to determine the phase composition.

A comparative study of the effect of high-pressure and low temperature on the crystal structure of lithium xanthinate hydrate.

The crystal structure of lithium xanthinate hydrate was studied by single crystal X-ray diffraction and Raman spectroscopy on cooling to 100 K and under compression to 5.3 GPa. A phase transition at ∼4 GPa is observed.

Metastatic brain lesion following gastrointestinal stromal tumor of the stomach complicated by coma.( A case report and literature review).

The authors present an extremely rare case of metastatic brain lesion in a patient with gastrointestinal stromal tumor of the stomach. There are literature data on 23 cases of metastatic lesions of the brain, skull and soft tissues of the head in similar patients. Atypical localization of metastases can lead to some diagnostic difficulties, unreasonable cancellation of chemotherapy and delayed surgical treatment.

Principles of biobanking and biobanks of central nervous system tumors in world practice.

Biobanks of central nervous system tumors are created in parallel with development of modern technologies for evaluation of molecular features of human diseases. In modern world practice, no one doubts that creation of biobanks of tumors is necessary and critical for personalized medicine. An important aspect of recent improvements in biobanks has been the expansion of tumor sample storage conditions.

Multimodal method of tissue differentiation in neurooncology using Raman spectroscopy, fluorescence and diffuse reflectance spectroscopy.

Background: There is a need to expand the possibilities of urgent analysis of intracranial tumor type during resection. These measures are necessary to improve resection quality with preservation of intact tissues and avoiding recurrence and neurological impairment in postoperative period.

Objective: To create optical-spectral method for differentiating the intracranial tumor types.

Arterial Spin Labeling Perfusion in Determining the IDH1 Status and Ki-67 Index in Brain Gliomas.

The aim of the study was to evaluate the relationship between tumor blood flow (TBF) measured by the pseudo-continuous arterial spin labeling (PCASL) method and IDH1 mutation status of gliomas as well as Ki-67 proliferative index. Methods. The study included 116 patients with newly diagnosed gliomas of various grades.

Bioavailability and Safety of Dihydroquercetin (Review).

Dihydroquercetin (DHQ) is a bioflavonoid with high antioxidant, capillary-protective, and anti-inflammatory activity. DHQ has previously been used for treating Middle East respiratory syndrome coronavirus (MERS-CoV) infection and is currently considered a potential regulator of oxidative stress as part of COVID-19 multipurpose therapy. DHQ has a high safety profile but low bioavailability that limits its use.

The behavior of zeolites wairakite and phillipsite at high P-T parameters.

In situ investigation of mineral behavior in water medium at simultaneously high P-T parameters can be applied to modelling of mineral transformation processes in lithospheric plates. The behavior of zeolites wairakite and phillipsite under the P-T conditions of «cold» slab subduction, corresponding to the start of oceanic plate diving or ocean floor near geothermal sources, was studied by in situ Raman spectroscopy. During compression in water medium, phillipsite initial phase is stable up to T = 350 °C, P = 1.

[Conduction aphasia in patients with glioma in the left hemisphere].

Unlabelled: Background. According to Wernicke-Geschwind model, conduction aphasia following arcuate tract lesion was canonized as primary disorder of repetition in relatively intact speech.

Objective: Syndromic analysis of speech and writing disorders in patients with arcuate tract lesion using the method by A.

[Visual fluorescence combined with laser spectroscopy in surgery for intramedullary spinal cord tumors].

Background: Surgical treatment of intramedullary spinal cord tumors is aimed at total resection of tumor with maximum preservation of neurological and functional status. In some cases, intramedullary tumors have unclear dissection plane or gliosis zone. This area is not a tumor and does not require resection.

[Comparative analysis of mono- and bipolar pyramidal tract mapping in patients with supratentorial tumors adjacent to motor areas: comparison of data at 64 stimulation points].

Objective: To compare monopolar and bipolar mapping in point-by-point fashion by using of threshold amperage, frequency of positive motor responses and the number of muscles involved in response.

Material And Methods: A prospective non-randomized study included 14 patients with supratentorial tumors who underwent surgery in 2018-2019. All neoplasms were localized within 2 cm from the motor cortex and pyramidal tract.

[Multicystic transformation of the post-radiation necrosis zone of the brain. A case report and literature review].

Post-radiation cyst of the brain is a rare complication that often arises many years after irradiation for head and neck neoplasms. The majority of the articles devoted to this problem are small samples or case reports. Nevertheless, the overall number of these patients is steadily increasing.

[Repetitive resection and intrasurgery radiation therapy of brain malignant gliomas: history of question and modern state of problem].

Numerous studies have shown that the degree of primary resection of malignant gliomas of the brain (MG) directly correlates with rates of relapse-free and overall patient survival. Currently, there is no unequivocal opinion regarding the indications and effectiveness of repeated resection in relapse of MG after combined treatment. Surgical intervention, taking into account the pathomorphological features of these tumors, is not healing and should be supplemented with certain methods of adjuvant treatment.

In Situ Raman Study of Liquid Water at High Pressure.

A pressure shift of Raman band of liquid water (HO) may be an important tool for measuring residual pressures in mineral inclusions, in situ barometry in high-pressure cells, and as an indicator of pressure-induced structural transitions in HO. However, there was no consensus as to how the broad and asymmetric water Raman band should be quantitatively described, which has led to fundamental inconsistencies between reported data. In order to overcome this issue, we measured Raman spectra of HO in situ up to 1.

Long association tracts of the human white matter: an analysis of 18 hemisphere dissections and in vivo HARDI-CSD tractography.

Background: Anatomy of the conduction tracts of the cerebral cortex has been studied for a long time. Invention of diffusion tensor tractography renewed interest in this subject. The objectives of this work were to develop and improve protocols for dissection of the long association tracts of the human brain with studying the features of their segmentation, topography, and variability, compare the obtained data with the MR tractography data, and prepare for further clinical and anatomical studies.

High-Pressure-High Temperature (HP-HT) Stability of Polytetrafluoroethylene: Raman Spectroscopic Study Up to 10 GPa and 600 ℃.

The increasing demand for use of polymers at extreme conditions makes important the exploration of their behavior in a wide pressure and temperature range, which remains unknown for polytetrafluoroethylene (PTFE), one of the most common materials. An in situ Raman spectroscopic study of PTFE shows that it is stable within the range of 2-6 GPa at 500 ℃ and up to 12 GPa at 400 ℃. At T > 500 ℃ and P > 3.

Raman investigation on the behavior of parasibirskite CaHBO at high pressure.

Knowledge about the stability of hydrous borates and borosilicates at high pressures are of critical importance to our understanding on the boron geochemical cycle. Raman spectroscopic measurements of parasibirskite CaHBO, containing the [BO(OH)] groups, have been made to pressures up to 5.4GPa.

The current state of the brain-computer interface problem.

It was only 40 years ago that the first PC appeared. Over this period, rather short in historical terms, we have witnessed the revolutionary changes in lives of individuals and the entire society. Computer technologies are tightly connected with any field, either directly or indirectly.

The long-associative pathway of the white matter: modern view from the perspective of neuroscience.

This review presents basic information about white matter tracts of the human brain, with a special emphasis being placed on long associative fibers (superior and inferior longitudinal fascicles, inferior frontooccipital fascicles, fasciculus arcuatus and fasciclus uncinatus): their structure, history, functions, methods of preoperative and intraoperative identification during neurosurgical operations. Neurological symptoms caused by a damage to each of the above-described long associative fiber are described. There is a detailed analysis of methods of neuropsychological testing and neurophysiological identification in white matter fiber tract mapping in focal brain lesions.

Treatment of poorly differentiated glioma using a combination of monoclonal antibodies to extracellular connexin-43 fragment, temozolomide, and radiotherapy.

Antitumor efficiencies of monoclonal antibodies to connexin-43 second extracellular loop (MAbE2Cx43), temozolomide, and fractionated γ-irradiation in the monotherapy mode and in several optimized combinations were studied in Wistar rats with induced C6 glioma. The survival of animals with glioma and the dynamics of intracerebral tumor development were evaluated by MRT. Temozolomide monotherapy (200 mg/m(2)) and isolated radiotherapy in a total dose of 36 Gy shifted the survival median from 28 days (no therapy) to 34 and 38 days, respectively; 100% animals died under conditions of temozolomide monotherapy and radiotherapy.

Phase diagram and high-pressure boundary of hydrate formation in the carbon dioxide-water system.

Experimental investigation of the phase diagram of the system carbon dioxide-water at pressures up to 2.7 GPa has been carried out in order to explain earlier controversial results on the decomposition curves of the hydrates formed in this system. According to X-ray diffraction data, solid and/or liquid phases of water and CO2 coexist in the system at room temperature within the pressure range from 0.

Pressure-induced phase transitions in crystalline L- and DL-cysteine.

A series of extended reversible phase transitions at approximately 0.1, 1.5, 2.

Phase diagram and high-pressure boundary of hydrate formation in the ethane-water system.

Dissociation temperatures of gas hydrate formed in the ethane-water system were studied at pressures up to 1500 MPa. In situ neutron diffraction analysis and X-ray diffraction analysis in a diamond anvil cell showed that the gas hydrate formed in the ethane-water system at 340, 700, and 1840 MPa and room temperature belongs to the cubic structure I (CS-I). Raman spectra of C-C vibrations of ethane molecules in the hydrate phase, as well as the spectra of solid and liquid ethane under high-pressure conditions were studied at pressures up to 6900 MPa.

New type of phase transformation in gas hydrate forming system at high pressures. Some experimental and computational investigations of clathrate hydrates formed in the SF6-H2O system.

In this work, we present a new, previously unknown type of structure transformation in the high-pressure gas hydrates, which is related to the existence of two different isostructural phases of the sulfur hexafluoride clathrate hydrates. Each of these phases has its own stability field on the phase diagram. The difference between these hydrates consists of partial filling of small D cages by SF(6) molecules in the high-pressure phase; at 900 MPa, about half of small cages are occupied.