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Currently, stem cells technology is an effective tool in regenerative medicine. Cell therapy is based on the use of stem/progenitor cells to repair or replace damaged tissues or organs. This approach can be used to treat various diseases, such as cardiovascular, neurological diseases, and injuries of various origins. The mechanisms of cell therapy therapeutic action are based on the integration of the graft into the damaged tissue (replacement effect) and the ability of cells to secrete biologically active molecules such as cytokines, growth factors and other signaling molecules that promote regeneration (paracrine effect). However, cell transplantation has a number of limitations due to cell transportation complexity and immune rejection. A potentially more effective therapy is using only paracrine factors released by stem cells. Secreted factors can positively affect the damaged tissue: promote forming new blood vessels, stimulate cell proliferation, and reduce inflammation and apoptosis. In this work, we have studied the anti-inflammatory and neuroprotective effects of proteins with a molecular weight below 100 kDa secreted by glial progenitor cells obtained from human induced pluripotent stem cells. Proteins secreted by glial progenitor cells exerted anti-inflammatory effects in a primary glial culture model of LPS-induced inflammation by reducing nitric oxide (NO) production through inhibition of inducible NO synthase (iNOS). At the same time, added secreted proteins neutralized the effect of glutamate, increasing the number of viable neurons to control values. This effect is a result of decreased level of intracellular calcium, which, at elevated concentrations, triggers apoptotic death of neurons. In addition, secreted proteins reduce mitochondrial depolarization caused by glutamate excitotoxicity and help maintain higher NADH levels. This therapy can be successfully introduced into clinical practice after additional preclinical studies, increasing the effectiveness of rehabilitation of patients with neurological diseases., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Salikhova, Shedenkova, Sudina, Belousova, Krasilnikova, Nekrasova, Nefedova, Frolov, Fatkhudinov, Makarov, Surin, Savostyanov, Goldshtein and Bakaeva.)

A sulfur-oxidizing, filamentous, gliding micro-organism, strain D3 T , was isolated from a sulfidic spring in Goryachy Klyuch, Krasnodar, Russia. The cell walls were Gram-negative. The new isolate was a microaerophilic facultative anaerobe and an obligate chemolithoautotroph. The pH range for growth was pH 6.8-7.6, with an optimum at pH 7.2. The temperature range for growth was 10-46 °C, with an optimum at 32 °C. The G+C content of DNA was 42.1 mol%. Phylogenetic analysis of the 16S rRNA gene showed that strain D3 T belongs to the family Beggiatoaceae, order Thiotrichales and was distantly related to the genera of the family Beggiatoaceae(86-88 % sequence similarity). The major respiratory quinone was ubiquinone-6. Major fatty acids were C18:1 ω7 (37.6 %), C16 : 0 (34.7 %) and C16: 1 ω7 (27.7 %). On the basis of its physiological properties and the results of phylogenetic analysis, strain D3 T is considered to represent a novel species of a new genus, for which the name Thioflexithrix psekupsensis gen. nov., sp. nov. is proposed. The type strain is D3 T (=KCTC 62399=UNIQEM U981).

Diazotrophic Alphaproteobacteria of the genus Azospirillum are usually organotrophs, although some strains of Azospirillum lipoferum are capable of hydrogen-dependent autotrophic growth. Azospirillum thiophilum strain was isolated from a mineral sulfide spring, a biotope highly unusual for azospirilla. Here, the metabolic pathways utilized by A. thiophilum were revealed based on comprehensive analysis of its genomic organization, together with physiological and biochemical approaches. The A. thiophilum genome contained all the genes encoding the enzymes of carbon metabolism via glycolysis, tricarboxylic acid cycle and glyoxylate cycle. Genes for a complete set of enzymes responsible for autotrophic growth, with an active Calvin-Benson-Bassham cycle, were also revealed, and activity of the key enzymes was determined. Microaerobic chemolithoautotrophic growth of A. thiophilum was detected in the presence of thiosulfate and molecular hydrogen, being in line with the discovery of the genes encoding the two enzymes involved in dissimilatory thiosulfate oxidation, the Sox-complex and thiosulfate dehydrogenase and Ni-Fe hydrogenases. Azospirillum thiophilum utilizes methanol and formate, producing CO 2 that can further be metabolized via the Calvin cycle. Finally, it is capable of anaerobic respiration, using tetrathionate as a terminal electron acceptor. Such metabolic versatility is of great importance for adaptation of A. thiophilum to constantly changing physicochemical environment., (© FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Filamentous sulfur bacteria of the genus Thiothrix are able to respire nitrate (NO3-→NO2-) under anaerobic growth. Here, Thiothrix caldifontis (G1(T), G3), Thiothrix unzii (A1(T), TN) and Thiothrix lacustris AS were shown to be capable of further reduction of nitrite and/or nitrous oxides (denitrification). In particular, in the genomes of these strains, excluding T. unzii TN, the nirS gene encoding periplasmic respiratory nitrite reductase was detected, and for T. lacustris AS the nirS expression was confirmed during anaerobic growth. The nirK gene, coding for an alternative nitrite reductase, and the nrfA gene, encoding nitrite reduction to ammonia, were not found in any investigated strains. All Thiothrix species capable of denitrification possess the cnorB gene encoding cytochrome c-dependent NO reductase but not the qnorB gene coding for quinol-dependent NO reductase. Denitrifying capacity ('full' or 'truncated') can vary between strains belonging to the same species and correlates with physical-chemical parameters of the environment such as nitrate, hydrogen sulfide and oxygen concentrations. Phylogenetic analysis revealed the absence of recent horizontal transfer events for narG and nirS; however, cnorB was subjected to gene transfer before the separation of modern species from a last common ancestor of the Thiothrix species., (© 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.)

The lithotrophic capacity of the betaproteobacteria Sphaerotilus natans subsp. sulfidivorans was confirmed at genetic level: functional genes of sulfur metabolism were detected (aprBA, soxB, and sqr, coding for adenylyl phosphosulfate reductase, thiosulfate-cleaving enzyme, and sulfide:quinone oxidoreductase, respectively), and the expression of aprA and soxB genes was demonstrated. An evolutionary scenario for soxB genes in Sphaerotilus representatives is suggested based on comparative analysis of codon occurrence frequency, DNA base composition (G + C content), and topology of phylogenetic trees. The ancestor bacterium of the Sphaerotilus-Leptothrix group was capable of lithotrophic growth in the presence of reduced sulfur compounds. However, in the course of further evolution, the sulfur metabolism genes, including the soxB gene, were lost by some Sphaerotilus strains. As a result, the lithotrophic Sphaerotilus-Leptothrix group split into two phylogenetic lineages, lithotrophic and organotrophic ones.

Intraocular pressure was estimated in patients with corneal disorders and secondary glaucoma. 25 patients (29 eyes) with complicated corneal opacities and secondary glaucoma were included into the study. In these patients the most reliable results were revealed using bidirectional corneal applanation (ORA) with contact lens on a cornea. If ORA is not available tonometer TGDc01-diaton should be used.