Diffuse Neuroendocrine System: Structural and Functional Effects of Radiation Injury to Amine Precursor Uptake and Decarboxylation (APUD) Cells

The paper presents a review of the results obtained by the authors on the study of external (gamma) and internal (I-131) radiation effects on the functional morphology and linkage of the diffuse neuroendocrine system (DNES) and amine precursor uptake and decarboxylation (APUD) cells of the stomach and duodenum. The investigations performed enabled us to determine that the morphological changes noted in APUD cells had a dose and time dependency. The present study supports the point of view that the radiation initiates serotonin release from APUD cells, which appears to initiate the mechanism of early postirradiation dysfunctions of the gastrointestinal tract and the subsequent adaptive response of DNES. Analysis of our results, together with a review of the literature, indicates that APUD cells actively participate both in pathogenesis of radiation injury and development of organ and tissue radiosensitivity

Features of the brainstem and its cavities in three-year-old children

Background: Little is known about the brainstem in healthy three-year-old children; yet there is a need for further studies because children at this age are growing and developing rapidly.Objective: To study differences in the brainstem and its cavities in healthy three-year-old children, considering the sex and bilateral asymmetry.Materials and methods: We retrospectively analyzed 120 MRI scans of healthy three-year-old children (60 boys and 60 girls) to study the brainstem features. The following parameters of the brain stem structures were assessed: 1) the length of the pons (mm), 2) the height of the pons (mm), 3) the length of the medulla oblongata (mm), 4) the height of the medulla oblongata at the upper and lower borders (mm), 5) the length and height of the vermis (mm), 6) the width of the cerebellum (mm), 7) the length, width, height of the cerebellar hemispheres (mm), 8) the length and height of the third ventricle, 9) the length of the cerebral aqueduct (mm), 10) the length and height of the fourth ventricle (mm). We assessed the compliance of quantitative parameters with the normal distribution according to the Kolmogorov-Smirnov criterion. We used Microsoft Excel 2016 tables to accumulate, correct and systemize the raw data. Statistica 10.0 software (StatSoft. Inc., USA) along with the corresponding statistical method provided the digital data. The differences were considered significant at P < .05.Results: We aimed to study sex-related differences in the basic sizes of the brainstem. The length and height of the pons, the length of the third and the fourth ventricles, and the size of the cerebellar hemispheres were greater in boys. We found a bilateral asymmetry in cerebellar hemispheres (length, width, and height).Conclusions: The changes in the complex brainstem of three-year-old children are sex-dependent and consist in active transformations of its structures

As-Grown Domain Structure in Calcium Orthovanadate Crystals

An as-grown domain structure in nominally pure and Mn-doped calcium orthovanadate (CVO) crystals was studied by several methods of domain imaging: optical microscopy, piezoelectric force microscopy, and Cherenkov-type second harmonic generation. The combination of imaging methods provided an opportunity for comprehensive study of the domain structure on the polar surface and in the bulk of the samples. It was shown that, in nominally pure CVO crystals, an irregular 3D maze of rounded domains, with charged walls, essentially tilted from the polar direction, was present. It was proposed that the domain structure was formed just below the phase transition temperature and persisted during subsequent cooling. Such behavior is due to effective bulk screening of the depolarization field and a low value of the pyroelectric field which appears during cooling. The revealed formation of triangular domains and flat fragments of domain walls in Mn-doped CVO was attributed to polarization reversal under the action of the polar component of the pyroelectric field, above the threshold value for domain switching. This fact represents the first observation of the domain switching in CVO crystals. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.Funding: This research was funded by the Russian Foundation for Basic Research, grant number 20-02-00588-a, and the Ministry of Science and Higher Education of the Russian Federation, grant numbers 075-15-2021-677 and FEUZ-2020-0054

Gender differences in the structure of the cerebrospinal fluid system of pre-school children

Relevance Investigation of the cerebrospinal fluid system of children of different ages, especially pre-school and school periods of childhood, becomes essential, since the further development of the brain and its proper functioning depends on the way it functions. Considering the MRI indications of the elements of the cerebrospinal fluid system of children is important for the development of neurology and neurosurgery, it is necessary to consider gender differences in the brain size and structure.Objective To study the sex differences in the structure of the cerebrospinal fluid system in seven-year-old children.Material and Methods For the study, archival data on the sizes of the lateral ventricles of the brain of 120 children aged 7 (60 boys and 60 girls) were involved, in particular: 1) the length of the anterior horn; 2) the width of the anterior horn; 3) the length of the central part; 4) the width of the central part; 5) the length of the posterior horn; 6) the width of the posterior horn; 7) the length of the lower horn; 8) the anteroposterior size; 9) the distance between the anterior horns; 10) the distance between the posterior horns; 11) the length of the third ventricle; 12) the height of the third ventricle; 13) the length of the aqueduct; 14) the length of the fourth ventricle; 15) the height of the fourth ventricle. The studies were carried out using the method of magnetic resonance imaging. Quantitative indicators were assessed for compliance with the normal distribution using the KolmogorovSmirnov test. The accumulation, correction, systematization of the initial information were carried out in Microsoft Excel 2016. Statistical analysis was carried out using the Statistica 10.0 software (StatSoft Inc., USA). The results were considered statistically significant at p < 0.05.Results The data obtained in the study of the cerebrospinal fluid system in children during their pre-school period of childhood are indicators of the norm and can be used for diagnostic studies in the departments of radiation diagnostics. The bilateral asymmetry of the lateral ventricles of the brain in pre-school children, discovered during the work, is of crucial clinical significance. The morphometric indicators of the elements of the cerebrospinal fluid system should be considered by specialists in the study of brain neuroplasticity.Conclusion Analysis of the obtained in vivo encephalometric data indicates the presence of sexual variability of the brain and parameters of the structures of the cerebrospinal fluid

Two cases of hydrophobia in the Republic of Tatarstan: In vivo and postmortem laboratory diagnosis

The results of rabies in vivo and postmortem laboratory detection in two cases registered in the Republic of Tatarstan are reported: a victim bitten by a wolf in 2002 and another one bitten by a stray dog on Goa Island, India, in 2013. In the patient bitten by a wolf cornea imprints studies using the method of fluorescent antibodies (MFA) showed rabies-positive result 6 days before the patient's death. The results were confirmed by postmortem examination of different parts of the brain and salivary glands using the MFA, enzyme-linked immunosorbent assay (ELISA), optical microscopy, and bioassay methods. In the patient bitten by a stray dog the rabies virus specific antigen was detected by eye cornea studies using the MFA method and saliva studies using the ELISA. The rabies virus genome was also isolated from saliva and tear fluid using nested reverse-transcription polymerase chain reaction (RT-PCR) 9 days before the patient's death. The in vivo studies results were consistent with the postmortem study of different parts of the brain using the MFA, enzyme-linked immunosorbent assay (ELISA), optical microscopy, and bioassay methods. All the infection-positive results of both in vivo and postmortem studies were consistent with the clinical studies, i.e. rabies diagnosis was confirmed. The analysis of the rabies virus gene G fragment nucleotide sequence of 238 nd length showed a slight difference between the studied isolates (2 rabies) and the RABV AY956319 (1.68%), difference by 10.5% from the Vnukovo-32 vaccine strains and by 10.9 % from the SAD B19 rabies strain, respectively (rabies viruses of 1st genotype). It was also significantly different from the lissaviruses of 2,4,5, and 6 genotypes (21.0-32.7%). The obtained results indicate phylogenetic closeness of the studied isolates (2 rabies) with the RABV AY956319 rabies virus strain belonging to the 1st genotype

Search for top squark pair production using dilepton final states in pp collision data collected at √s=13TeV

A search is presented for supersymmetric partners of the top quark (top squarks) in final states with two oppositely charged leptons (electrons or muons), jets identified as originating from bbquarks, and missing transverse momentum. The search uses data from proton-proton collisions at √s=13TeV collected with the CMS detector, corresponding to an integrated luminosity of 137fb−1. Hypothetical signal events are efficiently separated from the dominant top quark pair production background with requirements on the significance of the missing transverse momentum and on transverse mass variables. No significant deviation is observed from the expected background. Exclusion limits are set in the context of simplified supersymmetric models with pair-produced lightest top squarks. For top squarks decaying exclusively to a top quark and a lightest neutralino, lower limits are placed at 95% confidence level on the masses of the top squark and the neutralino up to 925 and 450GeV, respectively. If the decay proceeds via an intermediate chargino, the corresponding lower limits on the mass of the lightest top squark are set up to 850GeV for neutralino masses below 420GeV. For top squarks undergoing a cascade decay through charginos and sleptons, the mass limits reach up to 1.4TeV and 900GeV respectively for the top squark and the lightest neutralino

Search for the lepton flavor violating decay τ → 3μ in proton-proton collisions at √s = 13 TeV

Results are reported from a search for the lepton flavor violating decay τ → 3μ in proton-proton collisions at √s = 13 TeV. The data sample corresponds to an integrated luminosity of 33.2 fb−1 recorded by the CMS experiment at the LHC in 2016. The search exploits τ leptons produced in both W boson and heavy-flavor hadron decays. No significant excess above the expected background is observed. An upper limit on the branching fraction ℬ(τ → 3μ) of 8.0 × 10−8 at 90% confidence level is obtained, with an expected upper limit of 6.9 × 10−8

Measurements of the differential cross sections of the production of Z + jets and γ + jets and of Z boson emission collinear with a jet in pp collisions at √s = 13 TeV

Measurements of the differential cross sections of Z + jets and γ + jets production, and their ratio, are presented as a function of the boson transverse momentum. Measurements are also presented of the angular distribution between the Z boson and the closest jet. The analysis is based on pp collisions at a center-of-mass energy of 13 TeV corresponding to an integrated luminosity of 35.9 fb−1 recorded by the CMS experiment at the LHC. The results, corrected for detector effects, are compared with various theoretical predictions. In general, the predictions at higher orders in perturbation theory show better agreement with the measurements. This work provides the first measurement of the ratio of the differential cross sections of Z + jets and γ + jets production at 13 TeV, as well as the first direct measurement of Z bosons emitted collinearly with a jet

In-medium modification of dijets in PbPb collisions at √sNN = 5.02 TeV

Modifications to the distribution of charged particles with respect to high transverse momentum (pT) jets passing through a quark-gluon plasma are explored using the CMS detector. Back-to-back dijets are analyzed in lead-lead and proton-proton collisions at √sNN = 5.02 TeV via correlations of charged particles in bins of relative pseudorapidity and angular distance from the leading and subleading jet axes. In comparing the lead-lead and proton-proton collision results, modifications to the charged-particle relative distance distribution and to the momentum distributions around the jet axis are found to depend on the dijet momentum balance xj , which is the ratio between the subleading and leading jet pT. For events with xj ≈ 1, these modifications are observed for both the leading and subleading jets. However, while subleading jets show significant modifications for events with a larger dijet momentum imbalance, much smaller modifications are found for the leading jets in these events