18 research outputs found
LIGHT-HUMUS CARBONATE-ACCUMULATIVE AND PALE-METAMORPHIC SOILS IN THE COLLECTION OF V. V. DOKUCHAEV CENTRAL SOIL MUSEUM: VERIFICATION OF DIAGNOSTICS AT TYPE LEVEL
Results of 24 soil monoliths studying in the collection of Dokuchaev Central Soil Museum were analyzed in terms of diagnostic criteria in Russian soil classification system; these were chestnut, brown aridic, pale and cryoaridic soils. The topsoils of chestnut and brown aridic soils meet the criteria for the light-humus horizon (AJ), but their values in Munsell readings proved to be lower. In pale soils, the upper horizons were identified as gray-humus instead of light-humus ones as prescribed in the system. The cryohumus AK horizon, diagnostic for cryoaridic soils, is peculiar by the abundance of reddish frost-fragmented plant residues (detritus). We failed to differentiate metamorphic BM and xerometamorphic BMK horizon, they had more features of the latter. Both horizons are similar to the pale-metamorphic BPL horizon in color, although the BPL has a definitely weaker structure displaying some cryogenic features. These are less prominent in cryoaridic soils than in pale soils, hence, the diagnostic BPL horizon in cryoaridic soils may be removed to the category of diagnostic property. A similar re-evaluation may be proposed for the carbonate-textural CAT horizon: to consider it as a diagnostic property in the carbonate-accumulative horizon (ВСАt). The ВСА horizon in all soils studied differed by carbonate pedofeatures, namely, segregations in brown and chestnut soils, impregnations in pale soils, impregnations and coatings in cryoaridic soils
Comparative morphological characteristics of the uteroplacental area in abnormal placentation
The aim. To carry out a comparative morphological characteristic of the uteroplacental area with abnormal placentation – pl. accreta, pl. increta, pl. percreta. Materials and methods. The study included 47 patients with atypical placentation; the comparison group included 10 healthy pregnant women with uterine scar after a previous caesarean section. A histological study of uteroplacental area samples was performed with hematoxylin and eosin, methylene blue staining. An immunohistochemical study with primary antibodies to cytokeratin 7 (CK7), Hif2a, vascular endothelial growth factor, α-SMA was carried out. The differences between the compared values were considered to be statistically significant at p < 0.05. The results of the study. Pl. accreta was determined in 12 (25.5 %), pl. increta – in 30 (63.9 %), pl. percreta – in 5 (10.6 %) patients. In all patients of the main group, the decidua was completely or partially absent in the area of abnormal placentation or was replaced by an uneven layer of fetal fibrinoid. Cases when placental villi unevenly penetrated into the thickness of myometrium in the form of “tongues” or “coves” bordered by fetal fibrinoid and often located intermuscularly were defined as pl. increta (n = 26). Cases with the placental villi ingrowth to the serous membrane were considered as pl. percreta (n = 5). In cases with deep variants of ingrowth (pl. increta and pl. percreta) (n = 31), the villi were visualized in the lumen of the vessels and the thinning of the lower uterine segment with the presence of stretched muscle bundles was revealed. Aseptic necrosis of the myometrium was found: in 2 (16.7 %) of 12 women with pl. accreta, in 26 (86.7 %) of 30 women with pl. increta and in 5 (100 %) women with pl. percreta. There were no areas of necrosis in the myometrium of the women of comparison group. Conclusion. The appearance and increase of myometrial necrosis zones in response to an increase in the depth of placental villus ingrowth were detected. Myometrial necrosis zones could be the cause of activation of angiogenic factors and an important stimulus for the development of abnormal vascularization in placenta accreta spectrum
Desulfuribacillus alkaliarsenatis gen. nov. sp. nov., a deep-lineage, obligately anaerobic, dissimilatory sulfur and arsenate-reducing, haloalkaliphilic representative of the order Bacillales from soda lakes
An anaerobic enrichment culture inoculated with a sample of sediments from soda lakes of the Kulunda Steppe with elemental sulfur as electron acceptor and formate as electron donor at pH 10 and moderate salinity inoculated with sediments from soda lakes in Kulunda Steppe (Altai, Russia) resulted in the domination of a Gram-positive, spore-forming bacterium strain AHT28. The isolate is an obligate anaerobe capable of respiratory growth using elemental sulfur, thiosulfate (incomplete reduction) and arsenate as electron acceptor with H2, formate, pyruvate and lactate as electron donor. Growth was possible within a pH range from 9 to 10.5 (optimum at pH 10) and a salt concentration at pH 10 from 0.2 to 2 M total Na+ (optimum at 0.6 M). According to the phylogenetic analysis, strain AHT28 represents a deep independent lineage within the order Bacillales with a maximum of 90 % 16S rRNA gene similarity to its closest cultured representatives. On the basis of its distinct phenotype and phylogeny, the novel haloalkaliphilic anaerobe is suggested as a new genus and species, Desulfuribacillus alkaliarsenatis (type strain AHT28T = DSM24608T = UNIQEM U855T)
Verification of the Classification and Diagnostic system of Russian soils (2004) on the materials of a collection of soil monoliths from the V.V. Dokuchaev Central Soil Museum
Chloroflexus islandicus sp. nov., a thermophilic filamentous anoxygenic phototrophic bacterium from a geyser
Pyrimidine biosynthesis links mitochondrial respiration to the p53 pathway
While many functions of the p53 tumor suppressor affect mitochondrial processes, the role of altered mitochondrial physiology in a modulation of p53 response remains unclear. As mitochondrial respiration is affected in many pathologic conditions such as hypoxia and intoxications, the impaired electron transport chain could emit additional p53-inducing signals and thereby contribute to tissue damage. Here we show that a shutdown of mitochondrial respiration per se does not trigger p53 response, because inhibitors acting in the proximal and distal segments of the respiratory chain do not activate p53. However, strong p53 response is induced specifically after an inhibition of the mitochondrial cytochrome bc1 (the electron transport chain complex III). The p53 response is triggered by the deficiency in pyrimidines that is developed due to a suppression of the functionally coupled mitochondrial pyrimidine biosynthesis enzyme dihydroorotate dehydrogenase (DHODH). In epithelial carcinoma cells the activation of p53 in response to mitochondrial electron transport chain complex III inhibitors does not require phosphorylation of p53 at Serine 15 or up-regulation of p14ARF. Instead, our data suggest a contribution of NQO1 and NQO2 in stabilization of p53 in the nuclei. The results establish the deficiency in pyrimidine biosynthesis as the cause of p53 response in the cells with impaired mitochondrial respiration