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1.
Vopr Pitan ; 93(2): 52-62, 2024.
Artigo em Russo | MEDLINE | ID: mdl-38809799

RESUMO

The study of the genetic determinants of the disaccharidase activity opens up new prospects for improving diagnostics and choosing medical tactics in gastroenterology. The aim of the study was to systematize the data on the role of the sucrase-isomaltase gene (SI) in regulating sucrose metabolism and the contribution of SI mutations to the prevalence of sucrose malabsorption disorders (sucrase-isomaltase deficiency, SID) and certain forms of enterological pathology in different population groups. Material and methods. A review of the peer-reviewed scientific literature, mainly in the PubMed database (https://pubmed.ncbi.nlm.nih.gov) and eLibrary (https://elibrary.ru), was conducted using key words: carbohydrate malabsorption, sucrase, sucrase-isomaltase deficiency, sucrase-isomaltase SI gene. The search depth was not specified, but particular attention was paid to recent publications. The gnomAD database (https://www.ncbi.nlm. nih.gov/snp/rs781470490) was also used. Results. According to the review results, 37 out of 150 known SI gene mutations have been confirmed to contribute to reduced sucrase activity or restricted sucrase production. The prevalence of point mutations in the SI gene is estimated at 0.0006%, but carrier rates of the SI delAG deletion (rs781470490), manifested as homozygosity in SID, are very high (5-21%) in indigenous populations of Arctic regions in East Asia and America. Medicalgenetic research methods improve the accuracy of differential diagnosis of primary and secondary SID and other forms of disaccharide and polysaccharide malabsorption. The formation of databases on the prevalence of genetic determinants of sucrase-isomaltase insufficiency is a promising way to refine the epidemiology of SID. There is an increased (0.2-2.3%) risk of clinical manifestations of SID in homozygous carriers of the SI delAG mutation in the Chukotka, Kamchatka, and Northern Priochotye populations. Verification of reports on a less pronounced tendency to lipid metabolism disorders in SI delAG carriers compared with the control group is recommended. Conclusion. Manifestations of mutant SI variants in the phenotype are associated with the presence of accompanying carbohydrate malabsorption variants and specific gut microbiota. The SI 15Phe variant (rs9290264) may contribute to the development of irritable bowel syndrome.


Assuntos
Erros Inatos do Metabolismo dos Carboidratos , Complexo Sacarase-Isomaltase , Humanos , Erros Inatos do Metabolismo dos Carboidratos/genética , Complexo Sacarase-Isomaltase/genética , Complexo Sacarase-Isomaltase/deficiência , Mutação , Sacarose/metabolismo , Síndromes de Malabsorção/genética
2.
Zh Vopr Neirokhir Im N N Burdenko ; 88(1): 103-108, 2024.
Artigo em Russo | MEDLINE | ID: mdl-38334737

RESUMO

BACKGROUND: Planar hyperostotic meningiomas account for 2-9% of intracranial meningiomas. They are characterized by planar node following the contours of the inner surface of the skull. Hyperostosis is present in most cases. Timely diagnosis of skull base tumors is usually simple due to early involvement of the cranial nerves. However, convexity meningiomas en plaque usually reach large dimensions that complicates surgery and radiotherapy. OBJECTIVE: To analyze the current state of diagnosis, molecular biology and surgical treatment of hyperostotic meningiomas en plaque. MATERIAL AND METHODS: A systematic review was performed in accordance with the PRISMA guidelines. Searching for literature data included the following keywords: «planar meningioma¼, «hyperostotic meningioma¼, «meningioma en plaque¼, «infiltrative meningioma¼. We reviewed the PubMed and Google Scholar databases until May 2023 and enrolled only full-text Russian-, English- or French-language reports. RESULTS AND DISCUSSION: Among primary 332 reports, 35 references met the inclusion criteria. We found less severity or absence of focal neurological symptoms, comparable incidence of intracranial hypertension and no histological differences between planar and nodular meningiomas. Analysis of molecular biological features of planar meningiomas, including cell cultures, is feasible. There is no consensus regarding surgical treatment and radiotherapy. Most publications are case reports. CONCLUSION: The results of treatment of planar hyperostotic meningiomas, especially large and giant ones, are unsatisfactory. There is no a generally accepted algorithm for treating patients in the literature. This problem requires further research.


Assuntos
Neoplasias Meníngeas , Meningioma , Humanos , Meningioma/patologia , Meningioma/cirurgia , Meningioma/terapia , Neoplasias Meníngeas/cirurgia , Neoplasias Meníngeas/patologia , Neoplasias Meníngeas/terapia , Hiperostose/patologia , Hiperostose/etiologia
3.
Phys Rev Lett ; 130(5): 051801, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36800472

RESUMO

The KamLAND-Zen experiment has provided stringent constraints on the neutrinoless double-beta (0νßß) decay half-life in ^{136}Xe using a xenon-loaded liquid scintillator. We report an improved search using an upgraded detector with almost double the amount of xenon and an ultralow radioactivity container, corresponding to an exposure of 970 kg yr of ^{136}Xe. These new data provide valuable insight into backgrounds, especially from cosmic muon spallation of xenon, and have required the use of novel background rejection techniques. We obtain a lower limit for the 0νßß decay half-life of T_{1/2}^{0ν}>2.3×10^{26} yr at 90% C.L., corresponding to upper limits on the effective Majorana neutrino mass of 36-156 meV using commonly adopted nuclear matrix element calculations.

4.
Bull Exp Biol Med ; 176(2): 210-215, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38194065

RESUMO

We studied the mechanism of action of cytostatics with the addition of lysine acridone acetate to evaluate the possibility of its use for improving the effectiveness of antioncogenic therapy in colorectal cancer. In Nude mouse model, the level of apoptosis (TUNEL) and expression of proteins CD95, p53, Bcl-2, histone H3, and Ki-67 (immunohistochemistry) were assessed in primary tumor biopsy specimens. It has been shown that cytostatic treatment led to stimulation of p53-mediated apoptosis and suppression of proliferation (Ki-67 expression) of tumor cells, and apoptosis level was increased in groups receiving lysine acridone acetate. H3 expression in the experimental groups was changed.


Assuntos
Neoplasias Colorretais , Lisina , Animais , Camundongos , Lisina/farmacologia , Antígeno Ki-67/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Apoptose , Neoplasias Colorretais/patologia , Acridonas/farmacologia , Acetatos/farmacologia
5.
Vopr Pitan ; 92(6): 18-27, 2023.
Artigo em Russo | MEDLINE | ID: mdl-38198415

RESUMO

"Thrifty genotypes" are the risk factors for obesity and lipid and energy metabolism disorders. Hence, it is important to assess the contribution of environmental factors that influenced the thrifty genotypes' population distribution. Aim of the study - systematization and critical analysis of published data on population variability, relationship with climatic and environmental characteristics, association with traditional types of lifestyles, and nutrition for the «thrifty genotypes¼ of APOE, UCP1, UCP3, and FTO genes. Material and methods. The selection of publications from the last 20-25 years presented in the PubMed database (https://pubmed.ncbi.nlm.nih.gov) was carried out by the keywords of the generalizing rank (thrifty genotype, thrifty phenotype, drifty genotype), then narrowed down to the APOE, UCP, FTO. The final set includes publications that consider the association of genotypes with the ecological conditions of the population. Results. Our analysis of publications has confirmed the ethnic and geographical variability in the allele distribution of APOE, UCP1, UCP3, and FTO genes. However, the nature of this variability hasn't been studied sufficiently; the contribution of individual factors of the natural and anthropogenic environment remains unclear. The information on the geographical distribution of the APOE gene alleles is quite complete, while the data on the «thrifty genotypes¼ of UCP and FTO require further study. Conclusion. The frequency of the UCP1 and UCP3 alleles associated with effective non-contractile thermogenesis is increased in populations adapted to low temperatures. However, the population-geographical pattern of the UCP thrifty genotypes' variability as a determinant of increased fat deposition has been studied insufficiently. The carriage of FTO mutant variants increases the adaptability of groups with a traditional lifestyle and diet but is maladaptive in an urbanized environment. The influence of natural and ecological conditions on the formation of the FTO allele geographical distribution requires more attention. The results obtained allow us to propose the included groups' ranking according to the past environmental management and nutrition will facilitate the search for ecological factors that influenced the geographical distribution of genotypes (and, accordingly, populations with different levels of risk of metabolic disorders).


Assuntos
Doenças Metabólicas , Humanos , Prevalência , Genótipo , Alelos , Apolipoproteínas E , Dioxigenase FTO Dependente de alfa-Cetoglutarato
6.
Vopr Pitan ; 92(2): 53-59, 2023.
Artigo em Russo | MEDLINE | ID: mdl-37346020

RESUMO

To date, it has been established that the patient's genotype plays a significant role in the formation of trehalase enzymopathy: the level of enzyme activity decreases when the G→A allele replacement occurs in the rs2276064 locus of the TREH gene. To assess the prevalence of trehalase deficiency, extensive population-based studies are needed. Clinical observations show that the reduced activity of bowel trehalase is more common in the Arctic than in European populations. The aim of this research was to analyze the frequency of the alleles and variants of trehalase gene (rs2276064 TREH) in the indigenous small-numbered populations of Siberia and the Russian Far East. Material and methods. Using the Infinium iSelect HD Custom BeadChip biochip on the iScan platform and real-time polymerase chain reaction on a Bio-Rad CFX96 Touch amplifier, genotyping of 1068 DNA samples was carried out, of which 711 represent 10 ethnic groups of the indigenous people of the North of Siberia and the Far East of the Russian Federation. Two reference groups of Russians (n=311) and Yakuts (n=46) represented the "Caucasoid" and "Mongoloid" poles of the Russian population. Results. The reduced trehalase activity that the heterozygous GA*TREH genotype determines can manifest itself in 19.8-53.7% of indigenous northerners. An additional 1.0 to 19.7% of the population are carriers of the AA*TREH genotype, which is associated with apparent trehalose malabsorption. The carriers may experience nausea, abdominal pain, and other dyspeptic symptoms after eating trehalose containing foods. The total risk of trehalase enzymopathy among the indigenous northerners in the Asian part of the Russian Federation is very high and can reach 60-70%. There is a gradient in the A*TREH allele frequencies in the small-numbered indigenous northern groups of Russia from the west (Khanty, Mansi, Nenets) to the east (peoples of the Far East). Conclusion. The results are consistent with previously reported data on the higher carriage of the A*TREH mutant allele in Mongoloid populations compared to Caucasoid groups. It was hypothesized that, while the initial A*TREH allele prevalence in Mongoloid groups was moderately high, an adaptation to a low-sugar protein-lipid "high-latitude" diet led to a weaker control over the maintenance of the carriage of the ancestral G allele. Trehalose malabsorption requires special attention of specialists in the field of nutrition, gastroenterology, public health, and medical genetics working in high-latitude regions.


Assuntos
Trealase , Trealose , Humanos , Trealase/genética , Prevalência , Federação Russa/epidemiologia , Sibéria/epidemiologia
7.
Artigo em Inglês, Russo | MEDLINE | ID: mdl-36763560

RESUMO

Sphenoorbital meningiomas (SOM) are a subgroup of skull base tumors with soft tissue component in the orbit and anterior and/or middle cranial fossa. According to different authors, SOMs account for 2-12% of all intracranial meningiomas. Reconstruction of bone defects after resection of SOM has own nuances. Along with cranial vault repair, patients encounter with cosmetic defects following facial skull lesion, ophthalmic symptoms due to orbital defects, dental and functional problems associated with opening of the mouth in case of damage to maxilla and mandible. Predominant infiltrative growth of tumor and common large bone defects involving various anatomical regions require multiple implants or implants with complex shape. Moreover, contact of implantation area with nasal cavity and paranasal sinuses requires additional impermeability of soft tissue reconstruction and inertness of materials. OBJECTIVE: To summarize available modern data on bone defect closure after resection of SOM. MATERIAL AND METHODS: The authors reviewed available data on bone defect closure after resection of SOM. Effectiveness of modern methods of reconstruction and safety of materials were assessed. RESULTS: We analyzed 96 available references. Technical features of tumor resection, materials used for bone defect closure and modern possibilities of 3D technologies in reconstructive surgery were described. The authors proposed the algorithms for selecting the materials for bone defect closure after resection of SOM. CONCLUSION: Improvement of surgical technique and development of new materials and technologies significantly improve cosmetic and functional results. A large percentage of negative ophthalmologic outcomes and high risk of complications in SOM surgery require further studies and elaboration of modern techniques.


Assuntos
Neoplasias Meníngeas , Meningioma , Neoplasias da Base do Crânio , Humanos , Meningioma/diagnóstico por imagem , Meningioma/cirurgia , Neoplasias da Base do Crânio/diagnóstico por imagem , Neoplasias da Base do Crânio/cirurgia , Neoplasias Meníngeas/diagnóstico por imagem , Neoplasias Meníngeas/cirurgia , Órbita/cirurgia , Cavidade Nasal/patologia
8.
Artigo em Inglês, Russo | MEDLINE | ID: mdl-37830471

RESUMO

There are various approaches to the treatment of patients with parasagittal meningiomas. OBJECTIVE: To optimize treatment strategy for meningiomas invading the superior sagittal sinus. MATERIAL AND METHODS: The study included 87 patients with benign parasagittal meningiomas between 2010 and 2012. Of these, 34 patients underwent surgery alone, 27 - radiotherapy, 26 - surgery and subsequent radiotherapy. Both groups were comparable in male-to-female ratio, age and localization of tumors in relation to superior sagittal sinus. The follow-up period was at least 5 years. We analyzed the effect of treatment on neurological status, Karnofsky score and tumor growth control. RESULTS: Mean volume of tumors was 43.3 cm3 in patients undergoing surgery and 6.7 cm3 in the radiotherapy group. In the combined treatment group, mean volume was 65.8 cm3 before surgery and 8.8 cm3 before irradiation. General cerebral symptoms (84%), epileptic seizures (37%) and movement disorders (31%) prevailed. Surgery provided the best results in patients with small meningiomas (<14 cm3) causing focal neurological symptoms. Isolated radiotherapy was the most effective in asymptomatic patients. Large tumors required surgery with adjuvant irradiation. CONCLUSION: Benign parasagittal meningiomas followed by focal neurological symptoms require surgical intervention regarding the best functional outcomes and tumor growth control. Radiotherapy without surgery is advisable for progressive asymptomatic tumors. Resection followed by irradiation is preferable if total resection without the risk of damage to veins and cortex is impossible.


Assuntos
Neoplasias Meníngeas , Meningioma , Radiocirurgia , Humanos , Masculino , Feminino , Meningioma/radioterapia , Meningioma/cirurgia , Seio Sagital Superior/patologia , Seio Sagital Superior/cirurgia , Neoplasias Meníngeas/cirurgia , Resultado do Tratamento , Procedimentos Neurocirúrgicos/métodos , Seguimentos , Estudos Retrospectivos
9.
Zh Vopr Neirokhir Im N N Burdenko ; 87(5): 104-109, 2023.
Artigo em Inglês, Russo | MEDLINE | ID: mdl-37830475

RESUMO

Schwannomatoses is a new classification unit for all the hereditary diseases caused by chromosome 22 damage followed by multiple benign neoplasms of the peripheral and central nervous system. Schwannomatosis occurs as a result of damage to different genes: NF2, SMARCB1, LZRT1, loss of heterozygosity of the long arm of chromosome 22. Nevertheless, clinical manifestations are similar. Molecular diagnostics not only confirms the diagnosis, but also predicts the course of disease. Thus, the most severe clinical manifestations are observed in patients with violation of semantic sequences and reading frame shift in exons 2-13 of the NF2 gene. A more favorable course with less number of tumors is observed in patients with somatic mosaicism. Stereotactic irradiation and surgery are the main treatment options for schwannomatosis. However, there is evidence of effective targeted therapy with bevacizumab (inhibitor of vascular endothelial growth factor). Bevacizumab is used in patients with bilateral vestibular schwannomas and high risk of hearing loss, as well as for intramedullary tumor growth control.


Assuntos
Neurilemoma , Neurofibromatoses , Neurofibromatose 2 , Humanos , Bevacizumab , Fator A de Crescimento do Endotélio Vascular , Neurilemoma/genética , Neurilemoma/terapia , Neurofibromatoses/genética , Neurofibromatoses/terapia , Neurofibromatoses/diagnóstico , Neurofibromatose 2/genética , Neurofibromatose 2/terapia , Neurofibromatose 2/diagnóstico
10.
Artigo em Inglês, Russo | MEDLINE | ID: mdl-37011332

RESUMO

Dural defect closure after resection of cranioorbital meningiomas has its own specifics. Extended malignant lesions and common large bone defects involving various anatomical regions require multiple implants or implants with complex geometry. The features of this stage of reconstruction were described in the previous issue of the Burdenko Journal of Neurosurgery. At the same time, contact of implant with nasal cavity and paranasal sinuses dictates additional requirements for tightness of soft tissue reconstruction and inertness of material. In this review, we describe modern and historically interesting methods of reconstruction of soft tissue defects following resection of cranioorbital meningioma. OBJECTIVE: To summarize and analyze available literature data on reconstruction of soft tissue defects following resection of cranioorbital meningioma. MATERIAL AND METHODS: The authors reviewed available data on reconstruction of soft tissue defects after resection of cranioorbital meningiomas. Effectiveness of reconstruction techniques and safety of materials were analyzed. RESULTS: The authors analyzed 42 available full-text articles. Features of growth and natural course of cranioorbital meningioma, methods of soft tissue defects closure, modern materials and sealing compositions are described. Considering these data, the authors proposed the algorithms for selecting materials for dural reconstruction after resection of cranioorbital meningioma. CONCLUSION: Improvement of surgical technique, development of new materials and technologies increase the efficiency and safety of dural defect closure. Nevertheless, high incidence of complications associated with dura mater repair necessitates further research in this area.


Assuntos
Neoplasias Meníngeas , Meningioma , Procedimentos de Cirurgia Plástica , Humanos , Meningioma/cirurgia , Meningioma/patologia , Procedimentos Neurocirúrgicos/métodos , Dura-Máter/cirurgia , Neoplasias Meníngeas/cirurgia
11.
Artigo em Inglês, Russo | MEDLINE | ID: mdl-37830468

RESUMO

BACKGROUND: Pathogenesis of peritumoral cerebral edema is unclear and potentially associated with glymphatic system dysfunction. Diffusion tensor MRI (DT-MRI) with analysis of ALPS (Analysis along the Perivascular Space) index may be valuable for assessment of edema. This approach visualizes fluid flow along perivascular spaces of deep cerebral veins. OBJECTIVE: To assess glymphatic system function in supratentorial tumors and healthy volunteers using DT-MRI. MATERIAL AND METHODS: There were 52 patients (59% men) aged 43 (28-64) years with supratentorial tumors (meningioma - 20, grade 3-4 glioma - 15, metastases - 9, lymphoma - 8). Tumors and perifocal edema did not involve deep cerebral veins. The control group included 6 healthy volunteers aged 34-66 years. MRI protocol (Signa HDxt, 3 T) contained standard T1, T2, T2FLAIR, DWI and post-contrast T1 (3D BRAVO). DT-MRI had the following parameters: TR=10 000 ms, TEmin=102 ms, FOV=240 mm, isotropic voxel size 3×3×3 mm3, 60 directions of diffusion gradients. Measurements were carried out at b-factor 0 and 1000 s/mm2. Analysis was carried out in the ReadyView software. RESULTS: Right- and left-sided ALPS indices were similar in the control group (p=0.917). Perifocal edema (regardless of histological type of tumor) in the ipsilateral hemisphere was accompanied by significantly lower ALPS index (p<0.005), while these values in contralateral (intact) hemisphere were similar in both groups (p=0.7). CONCLUSION: We found significantly lower ALPS index in deep parts of the affected hemisphere in patients with perifocal edema. These data can indicate the role of glymphatic system dysfunction in pathogenesis of this pathology.


Assuntos
Neoplasias Encefálicas , Sistema Glinfático , Neoplasias Meníngeas , Neoplasias Supratentoriais , Masculino , Humanos , Feminino , Imagem de Tensor de Difusão/métodos , Neoplasias Encefálicas/patologia , Sistema Glinfático/diagnóstico por imagem , Sistema Glinfático/patologia , Imageamento por Ressonância Magnética , Edema
12.
Artigo em Inglês, Russo | MEDLINE | ID: mdl-37650273

RESUMO

Background. Meningiomas may be accompanied by peritumoral edema. Incidence and pathogenesis of edema are nor clearly established. Prevalence and severity of edema vary significantly in patients with meningiomas similar in various parameters. OBJECTIVE: To assess peritumoral edema in intracranial meningiomas and factors influencing incidence and severity of this process. MATERIAL AND METHODS: There were 126 patients (69% women) aged 19-76 years (median 53), who were diagnosed with 142 meningiomas. Patients underwent surgery (n=111) and radiotherapy (n=15) in 2016-2018. The MRI protocol included T1, T2, T2-FLAIR, DWI and post-contrast T1-weighted images in three projections, diffusion tensor MRI in 27 cases and MR spectroscopy in 21 patients. RESULTS: Peritumoral edema was detected in 46% (n=66) of cases including 21 (31%) patients with severe edema. The ALPS index was 1.510±0.1931 in meningiomas without edema and 1.308±0.19 in those with edema (p=0.014). There was positive correlation between edema, dimensions and uneven contours of meningioma, as well as negative correlation with CSF cleft sign. Blood flow velocity was higher in atypical and anaplastic meningiomas with edema (p=0.03). Other signs (localization, histological variant, malignancy grade, characteristics of MR signal, peaks of the main metabolites, diffusion and perfusion parameters of tumor) did not significantly affect peritumoral edema in patients with meningiomas (p>0.05). CONCLUSION: Diffusion tensor tomography with ALPS index revealed significant effect of glymphatic system dysfunction on peritumoral edema. Large meningioma with uneven contours increased the risk of peritumoral edema, while CSF cleft sign reduced this risk. Other factors did not affect cerebral edema in meningiomas.


Assuntos
Neoplasias Meníngeas , Meningioma , Humanos , Feminino , Masculino , Meningioma/complicações , Meningioma/diagnóstico por imagem , Imageamento por Ressonância Magnética , Edema , Neoplasias Meníngeas/complicações , Neoplasias Meníngeas/diagnóstico por imagem , Tomografia Computadorizada por Raios X
13.
Klin Lab Diagn ; 67(9): 511-518, 2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36099460

RESUMO

The culture method continues to be the "gold" standard for microbiological diagnosis of bloodstream infections. This is primarily due to the fact that the definition of the etiology of a generalized infectious process determines the etiotropic antibiotic therapy. To do this, it is necessary to conduct periodic microbiological monitoring of the prevailing microflora. To do this, in the present study, a retrospective analysis of the results of a microbiological blood test for sterility was performed in case of suspected bloodstream infections in a multidisciplinary hospital to assess the influence of analytical stage factors on the laboratory data obtained. Automatic hematological cultivators were used, identification was carried out based on the biochemical characteristics of microorganisms, as well as using time-of-flight mass spectrometry with matrix-activated laser desorption / ionization (MALDI-TOF MS). More than 10,000 research results were analyzed, the average microflora seeding rate was 15.1%. The analysis of the isolated microflora was carried out in 2 groups of positive results: at the beginning, the data obtained in the presence of growth in two vials at once were evaluated, then the positive results of blood cultures obtained in any one vial from a pair were studied. The predominance of gram-positive flora in the structure of microorganisms isolated from whole blood was revealed, the influence of cultivation conditions and the composition of thenutrient medium on the isolated flora was not found, however, a number of microorganisms, due to the specific characteristics of metabolism, were characterized by growth under strictly defined cultivation conditions. The presented study actualizes the need for constant microbiological monitoring in order to determine the prevailing hospital microflora, which can contribute to a timely response in order to limit the spread of highly virulent, aggressive, resistant strains of microorganisms leading to the development of generalized bloodstream infections.


Assuntos
Bacteriemia , Sepse , Bacteriemia/diagnóstico , Hospitais , Humanos , Estudos Retrospectivos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos
14.
Opt Lett ; 46(3): 556-559, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33528408

RESUMO

Population of the chemically active singlet 1Δg(0) state of molecular oxygen occurring due to direct laser excitation of the 1Δg(1)←3Σg-(0) transition has been observed for the first time, to the best of our knowledge, in oxygen molecules dissolved in organic solvents saturated with air under natural conditions (room temperature and normal atmospheric pressure). The data were obtained in 1 cm spectrophotometric cells due to the application of a set of high-power IR fiber and diode lasers. The rate of laser generation of the singlet (1Δg(0)) states in oxygen molecules was monitored by a chemical trapping method. It was found that the action spectra of singlet oxygen generation have one distinct band with a maximum at 1070 nm and half-width of ∼10nm. The absorption coefficients at 1070 nm were shown to be 100-110-fold lower than those at the main oxygen absorption peak (1273 nm) corresponding to the 1Δg(0)←3Σg-(0) transition. Under excitation at 810-1061 nm, very low trapping rates were observed, which did not depend on excitation wavelengths being probably caused by thermal effects. There was no reliable increase in the trapping rate under irradiation at 810 and 920 nm corresponding to the 1Δg(2,3)←3Σg-(0) transitions. This fact suggests that absorbance corresponding to these transitions is much lower than that at 1070 nm. The obtained results are important for both spectroscopy of oxygen and mechanistic studies of biological and therapeutic action of laser radiation.

15.
Opt Lett ; 46(7): 1684-1687, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33793518

RESUMO

The dynamics of electron excitations associated with the initiation of laser-induced damage in hafnia and silica monolayer films are investigated using time-resolved damage testing involving a pair of 0.7 ps pulses with adjustable delay and laser pulse fluences. Results in hafnia indicate that the relaxation profile depends on the pump-pulse fluence (initial excitation), and as a result, it exhibits an effective lifetime that is variable. Analogous experiments in silica form two different types of damage morphologies that are observed on different ranges of delay times.

16.
Arch Virol ; 166(6): 1591-1597, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33740120

RESUMO

This paper presents genetic data on the full genome analysis of A/chicken/Tajikistan/2379/2018 H9N2 influenza virus isolated in September 2018 from chicken pathological material received from poultry farms of the Republic of Tajikistan and subtyped as H9N2 by serological and molecular methods. According to the results of hemagglutinin gene sequencing, the amino acid sequence of the cleavage site was RSSR/GLF, which is typical for low-virulent avian influenza virus. Phylogenetic analysis of the nucleotide sequence of a hemagglutinin gene fragment (nt 1-1539 of the open reading frame) showed that the A/chicken/Tajikistan/2379/2018 H9N2 isolate belongs to the Y280 genetic group of low-virulent A/H9 influenza virus, which is widespread in Southeast Asia. The complete nucleotide sequence of the viral genome was determined. Comparative analysis of all genomic segments revealed that the A/chicken/Tajikistan/2379/2018 H9N2 virus is closely related to an A/H9 influenza virus isolated in the Far East of the Russian Federation in 2018. Genetic similarity (97.1-99% identity in four out of eight viral genes) was found to isolates of an H7N9 subtype virus recovered in the Inner Mongolia and Hebei regions of China in 2017. According to the analysis of the predicted amino acid sequence of the studied isolate, the positions of some molecular markers indicate possible adaptation of the virus to mammals. Further genetic analysis showed that this virus belongs to genotype G57.


Assuntos
Galinhas/virologia , Vírus da Influenza A Subtipo H9N2/genética , Influenza Aviária/virologia , Animais , Influenza Aviária/epidemiologia , Filogenia , Tadjiquistão/epidemiologia
17.
Chaos ; 31(4): 043122, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34251240

RESUMO

We study scenarios of the appearance of strange homoclinic attractors (which contain only one fixed point of saddle type) for one-parameter families of three-dimensional non-orientable maps. We describe several types of such scenarios that lead to the appearance of discrete homoclinic attractors including Lorenz-like and figure-8 attractors (which contain a saddle fixed point) as well as two types of attractors of spiral chaos (which contain saddle-focus fixed points with the one-dimensional and two-dimensional unstable manifolds, respectively). We also emphasize peculiarities of the scenarios and compare them with the known scenarios in the orientable case. Examples of the implementation of the non-orientable scenarios are given in the case of three-dimensional non-orientable generalized Hénon maps.

18.
Bull Exp Biol Med ; 172(2): 113-116, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34855093

RESUMO

Changes in the Shaganin lymphocyte index (ratio of the number of lymphocytes to segmented neutrophils) in the peripheral blood of rats after intraperitoneal administration of LPS (100 µg/kg) at the end of a single stress exposure in a model of 24-h restraint stress were studied. The lymphocyte index was analyzed 3 h later, on the 1st and 8th days after the stress load. Immobilization was accompanied by a decrease in this parameter 3 h after exposure. One day after the stress load, an increase in the lymphocyte index was noted, which remained on the 8th day of observation. LPS injection did not affect the changes in this parameter caused by 24-h immobilization on the 1st and 8th days of the study, but prevented a pronounced increase in the lymphocyte index on the 1st day after the stress load. The data obtained expand the existing scientific understanding of the specificity of the involvement of immunomodulatory substances in the implementation of adaptive-compensatory processes in mammals under conditions of emotional stress.


Assuntos
Lipopolissacarídeos/administração & dosagem , Linfócitos/patologia , Estresse Psicológico/sangue , Animais , Imobilização/fisiologia , Imobilização/psicologia , Injeções Intraperitoneais , Contagem de Leucócitos , Contagem de Linfócitos , Neutrófilos/patologia , Ratos , Ratos Wistar , Estresse Psicológico/induzido quimicamente , Estresse Psicológico/imunologia
19.
Vopr Pitan ; 90(5): 96-103, 2021.
Artigo em Russo | MEDLINE | ID: mdl-34719147

RESUMO

Due to the low specificity and sensitivity of non-invasive clinical tests trehalose malabsorption remained out of sight of gastroenterologists. Therefore, the specialists regard this disorder as rare. Trehalose became widely used in the food industry as a harmless sucrose substitute, sweetener and stabilizer. After the discovery of the trehalase gene (rs2276064 TREH), it was found that the A*TREH allele is the determinant of the disaccharide absorption disorders, and the allele's carriership may be high in some groups. There is not enough information on the A*TREH frequency in the population of Russia. The aim of the study was to analyze the allele and genotype frequencies of the trehalase gene (rs2276064 TREH) in the main population groups of the Russian Federation and neighboring countries. Methods. DNA samples from 1146 unrelated subjects belonging to 21 population groups of Russia, Azerbaijan, Tajikistan and Mongolia were genotyped by the two following methods: 1) using the Infinium iSelect HD Custom Genotyping BeadChip (Illumina, USA) on the iScan platform; 2) by the real time polymer-chain reaction (PCR) method on the Bio-Rad CFX96 Touch amplifier. Results. It has been found that on the territory of the Russian Federation the frequency of the A*TREH allele increases from the west to the east. The frequencies are lowest in the groups of Russians and Finns of the Northwest (0.01-0.03), up to 0.07 in the populations of Central Russia and the Volga region, and even higher toward the Southern Urals (Bashkirs 0.15), in the Transurals and Southern Siberia (0.19 in the Altai people, 0.30 in the Tuvinians and Mongols). Up to 1% of the population of the European part of the Russian Federation have the AA*TREH genotype (i.e. trehalose intolerance in phenotype), and up to 15% (GA*TREH genotype) have a reduced ability to absorb the disaccharide. In the Asian part of the country (Siberia, Altai, Baikal) the genotypes carriers constitute up to 12 and 46% respectively. Conclusion. Trehalose malabsorbtion is an underappreciated problem of particular practical importance for regions with high concentrations of indigenous population (Yakutia-Sakha, Buryatia, Tyva, etc.). It would be feasible to consider food labelling of trehalose.


Assuntos
Erros Inatos do Metabolismo dos Carboidratos/epidemiologia , Grupos Populacionais , Trealase , Alelos , Diarreia/epidemiologia , Humanos , Federação Russa/epidemiologia , Trealase/deficiência , Trealase/genética , Trealose
20.
Artigo em Russo | MEDLINE | ID: mdl-34714003

RESUMO

INTRODUCTION: Stereotactic method and new irradiation techniques ensured radiosurgical treatment with high precision and conformity and significantly expanded the indications for stereotactic irradiation in neurosurgery. MATERIAL AND METHODS: Over 15-year period, 29 976 patients underwent irradiation in various modes of fractionation on linear accelerators and Gamma Knife system at the first national radiosurgery center. RESULTS: Stereotactic radiotherapy and radiosurgery are followed by minimal number of complications and side reactions. At the same time, 5-year control of tumor growth for skull base meningioma was 96.8%, neuroma - 97%, glomus tumor - 94%, pituitary adenoma - 96-98%, craniopharyngioma - 95% in overall 10-year survival 86%, pilocytic astrocytoma - 97.5% in overall 5-year survival 99%. In intracranial metastases, median overall survival after radiosurgery was 10.1 months, 24- and 36-month overall survival - 25.9% and 19.2%, respectively. In patients with recurrent high-grade glioma, overall survival was 27.4 months. In case of metastatic spine lesions, control of tumor growth within 1 year was achieved in 90% of patients, pain relief - in more than 50% of cases. Obliteration of AVM and dural fistula was found in more than 80% of patients in years after treatment. Reduction or disappearance of pain was also observed in 80% of patients with trigeminal neuralgia. CONCLUSION: Stereotactic irradiation is effective and safe in patients with various pathologies of the central nervous system and characterized by high socio-economic indicators. Our own data indicate more significant role of stereotactic irradiation in the treatment of neurosurgical patients and make it possible to revise the existing treatment standards.


Assuntos
Neoplasias Encefálicas , Tumor Glômico , Neoplasias Meníngeas , Radiocirurgia , Aniversários e Eventos Especiais , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/cirurgia , Seguimentos , Humanos , Neoplasias Meníngeas/cirurgia , Estudos Retrospectivos , Resultado do Tratamento
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