Changes in the Tissue Barrier after Exposure to Lipopolysaccharide on the Apical Side of Enterocytes and the Follicle-Associated Epithelium in Peyer's Patches of the Rat Intestine.

To study the para- and transcellular permeability of columnar epithelium and follicle-associated epithelium of Peyer's patches in the rat intestine, LPS was applied from the mucosal side to simulate the action of endotoxins from gram-negative bacteria of gut microbiota. LPS did not affect transepithelial resistance or sodium fluorescein permeability, but increased the levels of claudin-3 and claudin-4 in enterocytes, suggesting strengthening of the paracellular intestinal barrier. Transcellular permeability was evaluated by electron microscopy based on the number of vesicular structures in the cytoplasm of different cell types. LPS increased the number of small vesicles in follicle-associated epithelium of Peyers' patches. In columnar epithelial cells, LPS reduced the number of smaller vesicles and increased the number of larger ones. LPS did not damage the tissue barrier, but enhanced transcytosis, which could potentiate the effects of endotoxin on its receptors in the intestinal mucosa.

Global Vertical Distribution of Water Vapor on Mars: Results From 3.5 Years of ExoMars-TGO/NOMAD Science Operations.

We present water vapor vertical distributions on Mars retrieved from 3.5 years of solar occultation measurements by Nadir and Occultation for Mars Discovery onboard the ExoMars Trace Gas Orbiter, which reveal a strong contrast between aphelion and perihelion water climates. In equinox periods, most of water vapor is confined into the low-middle latitudes. In aphelion periods, water vapor sublimated from the northern polar cap is confined into very low altitudes-water vapor mixing ratios observed at the 0-5 km lower boundary of measurement decrease by an order of magnitude at the approximate altitudes of 15 and 30 km for the latitudes higher than 50°N and 30-50°N, respectively. The vertical confinement of water vapor at northern middle latitudes around aphelion is more pronounced in the morning terminators than evening, perhaps controlled by the diurnal cycle of cloud formation. Water vapor is also observed over the low latitude regions in the aphelion southern hemisphere (0-30°S) mostly below 10-20 km, which suggests north-south transport of water still occurs. In perihelion periods, water vapor sublimated from the southern polar cap directly reaches high altitudes (>80 km) over high southern latitudes, suggesting more effective transport by the meridional circulation without condensation. We show that heating during perihelion, sporadic global dust storms, and regional dust storms occurring annually around 330° of solar longitude (L S) are the main events to supply water vapor to the upper atmosphere above 70 km.

Global Variations in Water Vapor and Saturation State Throughout the Mars Year 34 Dusty Season.

To understand the evolving martian water cycle, a global perspective of the combined vertical and horizontal distribution of water is needed in relation to supersaturation and water loss and how it varies spatially and temporally. The global vertical water vapor distribution is investigated through an analysis that unifies water, temperature and dust retrievals from several instruments on multiple spacecraft throughout Mars Year (MY) 34 with a global circulation model. During the dusty season of MY 34, northern polar latitudes are largely absent of water vapor below 20 km with variations above this altitude due to transport from mid-latitudes during a global dust storm, the downwelling branch of circulation during perihelion season and the intense MY 34 southern summer regional dust storm. Evidence is found of supersaturated water vapor breaking into the northern winter polar vortex. Supersaturation above around 60 km is found for most of the time period, with lower altitudes showing more diurnal variation in the saturation state of the atmosphere. Discrete layers of supersaturated water are found across all latitudes. The global dust storm and southern summer regional dust storm forced water vapor at all latitudes in a supersaturated state to 60-90 km where it is more likely to escape from the atmosphere. The reanalysis data set provides a constrained global perspective of the water cycle in which to investigate the horizontal and vertical transport of water throughout the atmosphere, of critical importance to understand how water is exchanged between different reservoirs and escapes the atmosphere.

Novel amphiphilic compounds effectively inactivate the vaccinia virus.

Recent studies demonstrated the ability of artificial ribonucleases (aRNases, small organic RNA cleaving compounds) to inactivate RNA-viruses via the synergetic effect of viral RNA cleavage and disruption of viral envelope [1,2]. Herein, we describe the antiviral activity of aRNases against DNA-containing vaccinia virus: screening of aRNases of various structures revealed that amphiphilic compounds built of positively charged 1,4-diazabicyclo[2.2.2] octane substituted at the bridge nitrogen atoms with aliphatic residues efficiently inactivate this virus. The first stage was the destruction of viral membrane and structure of surface proteins (electron microscopy data). Thus, 1,4-diazabicyclo[2.2.2] octane-based aRNases are novel universal agents inactivating both RNA- and DNA-containing viruses.

[Potential of impression cytology in diagnosis and evaluation of efficacy of pharmacological correction of dry eye syndrome associated with contact lens wearing].

Potential of impression cytology in diagnosis and evaluation of efficacy of pharmacological correction of dry eye syndrome (DES) associated with contact lens wearing was studied. When wearing contact lenses for a long time DES with tear film instability and reduction of tear production occurs in more than 50% patients. Morphological changes of epithelium of tarsal and bulbar conjunctiva manifest consequently. Impression cytology reveals structural damage of epithelium with keratinization signs and decrease of goblet cells density down to total absence. After tear substitution therapy tear break-up time increased by 65,3% and total tear production by 11,4%. In control impression cytology of tarsal and bulbar conjunctiva during tear substitution therapy the following changes were revealed: recovery of goblet cells density and differentiation, recovery of epithelial structure and reduction of epithelium keratinization.

RNase T1 mimicking artificial ribonuclease.

Recently, artificial ribonucleases (aRNases)--conjugates of oligodeoxyribonucleotides and peptide (LR)(4)-G-amide--were designed and assessed in terms of the activity and specificity of RNA cleavage. The conjugates were shown to cleave RNA at Pyr-A and G-X sequences. Variations of oligonucleotide length and sequence, peptide and linker structure led to the development of conjugates exhibiting G-X cleavage specificity only. The most efficient catalyst is built of nonadeoxyribonucleotide of unique sequence and peptide (LR)(4)-G-NH(2) connected by the linker of three abasic deoxyribonucleotides (conjugate pep-9). Investigation of the cleavage specificity of conjugate pep-9 showed that the compound is the first single-stranded guanine-specific aRNase, which mimics RNase T1. Rate enhancement of RNA cleavage at G-X linkages catalysed by pep-9 is 10(8) compared to non-catalysed reaction, pep-9 cleaves these linkages only 10(5)-fold less efficiently than RNase T1 (k(cat_RNase T1)/k(cat)_(pep)(-9) = 10(5)).

[Detection of sodium monourate crystals in biopsies of gastric mucosa in patients with gout]. / Vyiavlenie kristallov monourata natriia v bioptatakh slizistoi obolochki zheludka u bol'nykh podagroi.

AIM: To examine gastric biopsies with polarization microscopy for detection of sodium monourate crystals (SMC). MATERIAL AND METHODS: The trial included 20 patients with gout diagnosis (mean age 55.7 years, mean duration of the disease 12.3 years) in whom esophagogastroduodenoscopy was made with biopsy of gastric mucosa from the antral part of the stomach and middle third of the gastric body. RESULTS: Crystals in the biopsy specimens were detected in 11 of 20 examinees. The crystals were characterized by strong double refraction, length 3-20 mcm, acicular or planiform shape, blue or yellow color depending on position in compensated polarized light. Quantitative distribution of the crystals within one biopsy specimen was uneven and varied from solitary crystals to clusters of 70-80 crystals in sight, up to formation of tophus-like structures. Clinical picture in detection of SMC was characterized by more frequent occurrence of cases with subcutaneous tophuses of various location combined with higher hyperuricemia. CONCLUSION: One of the essential lines in the research of gout concerns mechanisms of SMC formation in organs and tissues and microcrystalline gastroduodenal inflammation. Methods of correction of this inflammation are to be designed.

[Cytogenetic changes in peripheral blood lymphocytes in people with impaired thyroid status]. / Tsitogeneticheskie izmeneniia v limfotsitakh periferichskoi krovi lits s narushennym tireoidnyum statusom.

Increased counts of cells with chromosome aberrations were revealed in peripheral blood lymphocytes of subjects with thyroid dysfunction: 5.5 +/- 0.6% in hypothyrosis, 9.0 +/- 1.8% in hyperthyroidism, and 2.5 +/- 0.1% in controls (20 donors). The aberrations are mainly presented by paired and solitary fragments, rarely by chromatid translocations; in two patients with hyperthyroidism dicentrics were detected. Distribution of aberration types varied. In hypothyrosis chromosome aberrations were two times more incident than chromatid ones. In hyperthyroidism chromosome and chromatid aberrations were approximately equally incident. These results may be used to explain the causes of unfavorable outcomes of pregnancy in patients with thyroid diseases.

[Effect of thyroxine in the G0 stage of the cell cycle on the yield of chromosome aberrations in rat hepatocytes and human lymphocytes after X-irradiation]. / Vliianie tiroksina v stadii G0 kletochnogo tsikla na vykhod aberratsii khromosom v gepatotsitakh krys i limfotsitakh cheloveka posle rentgenovskogo oblucheniia.

A study was made of the mechanism of a modifying action of thyroxin (T4) on the chromosome integrity after the application thereof in vivo and in vitro following a single whole-body exposure to X-radiation with a dose of 2.19 Gy. It is concluded that T4 influences the quantity of cells with chromosome aberrations stimulating the recovery of the chromosome integrity: the stimulation can be brought about at the G0 stage of the cell cycle as a result of the direct effect of the hormone on a cell.

[Effect of thyroxine on the integrity of chromosomes]. / O vliianii tiroksina na tselostnost' khromosom.

Some features of the mechanism of thyroxin (T4) mutagenic effect in the culture of the human peripheral blood lymphocytes and the rat liver in vivo were studied. It was shown, that T4 mutagenic effect, discovered previously in the entire organism, can be stipulated by direct hormone-cell interaction. T4 mutagenic effect is associated with a change in DNA-dependent RNA polymerase activity and is realized during different phases of the cellular cycle. T4 modifying influence upon chromosome entirety is substantially limited by the age.