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Nitrones cycloaddition to 1-vinyl-4,5-dihydro-1 H-benzo[ g]indole proceeds regio- and steroselectively affording a single diastereomer of 5-(hetaryl-substituted)isoxazolidine. [ABSTRACT FROM AUTHOR]

Palaeointensity study of the Proterozoic–Archean volcanic rocks from the Kaapvaal Craton South Africa) are reported. Palaeomagnetic study of this collection was performed earlier by Olsson et al. Electron microscope observations, thermomagnetic and hysteresis measurements indicate the presence of single-domain and pseudo-single-domain (SD-PSD) magnetite grains as the main magnetic mineral. The samples demonstrated a very good stability to heating, the electron micrograph observations revealed magnetite–ilmenite exsolution structure. Palaeointensity determinations were obtained by Coe-modified Thellier procedure. A total 58 samples from 14 sites were studied but only seven samples from one site NL28 of the Early Proterozoic age of 1.9 Ga passed palaeointensity selection criteria. Reliable palaeointensity determinations were obtained by both Thellier and Wilson methods on 18 cubes (subsamples) from site NL28 yielding rather low mean virtual dipole moment (VDM) = (2.82 ± 0.12) ×1022 Am2 which is in agreement with the suggestion of existence of the ‘Proterozoic dipole low period’. [ABSTRACT FROM PUBLISHER]

A new method for the synthesis of benzofuro[3,2-d]pyrimidines was developed based on the oxidation of 2-(5-bromo-3,4-dihydropyrimidin-4-yl)phenols followed by the intramolecular nucleophilic aromatic substitution reaction. [ABSTRACT FROM AUTHOR]

1-(1-Methyl-1 H-pyrrol-2-yl)prop-2-yn-1-ol has been synthesized for the first time by ethynylation of 1-methyl-1 H-pyrrole-2-carbaldehyde with acetylene in the superbasic system KOH-DMSO-HO under atmospheric pressure. [ABSTRACT FROM AUTHOR]

A comparative analysis of carbohydrate degradation proteins encoded in the currently available genomic sequences of bacteria of the family Sphaerochaetaceae, namely Sphaerochaeta associata GLS2T, S. globosa BuddyT, S. pleomorpha GrapesT, S. halotolerans 4-11T, S. halotolerans 585, Sphaerochaeta sp. S2, Sphaerochaeta sp. PS, and Parasphaerochaetacoccoides SPN1T was carried out. The genomes of Sphaerochaeta spp. encode a medium-sized and diverse set of proteins potentially involved in the degradation of different classes of carbohydrates, mainly oligosaccharides. All studied genomes encode glycoside hydrolases of the GH1, GH2, GH3, GH4, GH13, GH20, GH28, GH36, GH43, GH57, GH63, GH77 and GH105 families, as well as carbohydrate esterases of the CE8 and CE9 families. All studied bacteria, with the exception of P. coccoides SPN1T, have many genes of the GH31 family proteins. The studied members of Sphaerochaetaceae do not have genes coding for endo-β-acetylmuramidase (lysozyme) of the GH23 family, which participates in peptidoglycan turnover. However, the genomes of S. associata, S. globosa, Sphaerochaeta sp. PS, and S. pleomorpha contain exo-β-acetylmuramidase genes (GH171 family). A significant part of the genes encoding carbohydrate degradation enzymes have the closest homologues among representatives of the phyla Bacillota, Bacteroidota, and Pseudomonadota. The genomes of the studied bacteria encode proteins that could potentially be involved in the degradation of pectin. The ability of the Sphaerochaetaceae members to use pectin for growth, as well as the evolutionary origin of the genes encoding potential α-galacturonidase (GH4 family) and unsaturated glucuronyl/rhamnogalacturonyl hydrolase (GH105 family), which participate in the degradation of pectin components, were studied. [ABSTRACT FROM AUTHOR]

We report results of paleomagnetic studies of mafic dikes and sills from the Tas-Yuryakh magmatic complex on the Olenek uplift in the northeast of the Siberian platform. The paleomagnetic record in the rocks corresponds to an episode of anomalous state of the geomagnetic field that persisted from the Ediacaran period (~580 Ma and younger) to the end of the Fortunian age. Paleointensity measurements indicate an extremely low value of the virtual dipole moment during this time. This presumably caused a disruption of the normal Geocentric Axial Dipole model, so much so that the world magnetic anomalies made a substantial contribution. We propose that the Antarctic anomaly influenced the magnetization of the Siberian craton rocks during this period of very low dipole moment. The high latitudes corresponding to the observed paleopole do not correspond to the actual paleogeography of Siberia and can be used for paleoreconstructions only after adjusting for this anomaly. The true position of the Olenek uplift at the Precambrian–Paleozoic boundary was close to 30° S above the southeastern periphery of the African (Tuzo) mantle hot field. [ABSTRACT FROM AUTHOR]

We present new results of geochronological, rock magnetic, paleomagnetic and paleointensity studies of the olivine gabbro dyke located at the northern part of the Murmansk craton, NE Fennoscandia (the Kola Peninsula). According to its geochemistry, petrographic and geochronology features, the dyke belongs to the 2.68 Ga dyke swarm, as confirmed by Sm-Nd mineral isochron. We find a significant difference in the rock magnetic and paleomagnetic characteristics of the central and marginal parts of the dyke, which is independently supported by petrography and geochemistry. It is shown that the rocks of the central part of the dyke retained not only their primary mineral composition, but also the primary component of the natural remanent magnetization. We use its direction to determine the 2.68 Ga virtual geomagnetic pole for the Murmansk craton: Slat = 68.64292° N, Slong = 37.7945° E, N = 41 specimens, Plat = –73.5°, Plong = 138.9°, dp/dm = 3.2°/3.4°, paleolat = –65.9°. We also obtain reliable estimates (17 samples) of the Earth's magnetic field intensity at ca. 2.68 Ga: VDM value is found to be 1.85 × 1022 A m2 corresponding to the geomagnetic field several times weaker than the present-day field. [ABSTRACT FROM AUTHOR]

3H-melatonin binding sites were found in the cell membrane fraction from the thyroid gland of Wistar rats and their kinetic characteristics were determined. The number of receptors and dissociation constant depend on the duration of daytime, which probably determines rhythmic fluctuation of the sensitivity of thyrocytes to melatonin. [ABSTRACT FROM AUTHOR]

An obligately anaerobic bacterium, strain Bkl1T, was isolated from an enrichment culture of iron-reducing bacteria (IRB) obtained from a sample of the bottom sediments of the cold freshwater Lake Baikal (Russia). Cells of the strain were Gram-stain-negative, motile, spore-forming straight rods (0.6–0.7 × 2.0–7.0 µm) with a fermentative metabolism. Strain Bkl1T grew in the temperature range from 7 to 38°C (optimum 20°C) and at pH 7.0–9.5 (optimum pH 7.6). The novel isolate was capable to reduce ferric citrate (FC), anthraquinone-2,6-disulfonate (AQDS) and Cr(VI) in the presence of lactate as carbon source. Ferrihydrite was not reduced in the absence of AQDS. Based on its 16S rRNA gene sequence, strain Bkl1T was affiliated to the family Sporomusaceae and, more specifically, to the genus Pelosinus. The strain was most closely related to Pelosinus fermentans DSM 17108T (99.2%) and P. propionicus DSM 13327T (99.1%). Genome relatedness indexes revealed that the average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between strain Bkl1T and its closest phylogenomic relative (P. fermentans DSM 17108T) were 93.3 and 54.2%, respectively. The G + C content of the genome of strain Bkl1T was 39.1 mol % and its size was 5.32 Mb with 4939 protein-coding genes. The predominant fatty acids in cell walls were С15:1, С17:1, and С16:1. Based on the phylogenetic analyses and phenotypic differences between the novel isolate and type strains of the genus Pelosinus, strain Bkl1T (=VKM B-3511Т = JCM 39258T) is proposed to represent a novel species Pelosinus baikalensis sp. nov. [ABSTRACT FROM AUTHOR]

A new strain of methanogenic archaea, designated VTT, was isolated from a sample of Spitsbergen permafrost. The cells were nonmotile curved rods, 2.7–5.3 × 0.3 µm. The optimal conditions for growth were 20°C, pH 6.6, and NaCl concentrations 0.03–0.05 M. The H2/CO2 gas mixture was the only substrate used. In the presence of H2/CO2, growth was stimulated by addition of yeast extract or rumen fluid. Phylogenetic analysis of the 16S rRNA gene sequences indicated that strain VTT belonged to the genus Methanobacterium and was most closely related to M. lacus 17A1T (97.02% similarity). Comparison of the sequenced and assembled genome of strain VTT with the genomes of other members of this genus confirmed these results and revealed species-level differences. Our results indicate that this methanogenic isolate belongs to a new species of methanogenic archaea, for which the name Methanobacterium spitsbergense sp. nov. was proposed, with the type strain VTT (=VKM B-3566T = JCM 39284T). [ABSTRACT FROM AUTHOR]

Background: Frequent early postoperative complications of hemorrhoidectomy are thrombosis and edema of mucocutaneous "bridges.", Objective: This study aimed to investigate the efficacy of micronized purified flavonoid fraction in preventing complications after elective hemorrhoidectomy., Design: Prospective unicentral open-label randomized controlled trial., Settings: 2021-2022 at the Clinic of Colorectal and Minimally Invasive Surgery at Sechenov University (Moscow, Russia)., Patients: Patients who underwent hemorrhoidectomy for grade III and IV hemorrhoids., Interventions: After hemorrhoidectomy, patients were randomly assigned either to standard treatment (peroral nonsteroid anti-inflammatory drugs and local anesthetics, topical steroids, psyllium, warm sitz baths, and nifedipine gel), referred to as the control group, or to standard treatment with micronized purified flavonoid fraction, referred to as the study group, and followed up for 60 days., Main Outcome Measures: Thrombosis or edema of mucocutaneous bridges and pain intensity on a visual analog scale оn postoperative days 1-7, 14, 21, and 30; quality of life and patient-assessed treatment effect оn postoperative days 1, 3, 7, 21, and 30; and perianal skin tags оn postoperative day 60., Results: The data from 50 patients were analyzed (25 in each group). The visual analog scale demonstrated no differences between groups in each follow-up point. Compared to the control group, the patients in the study group had a significantly higher patient-assessed treatment effect оn postoperative days 1, 3, 7, 21, and 30 and a significantly lower rate of thrombosis or edema of mucocutaneous bridges оn postoperative days 1-7 and 14. Patients in the study group had significantly lower rates of perianal skin tags., Limitations: Unicenter open-label design., Conclusions: Micronized purified flavonoid fraction in the posthemorrhoidectomy period is an effective adjunct to standard treatment that helps reduce the rate of thrombosis and edema of mucocutaneous bridges, improves patient-assessed treatment effect, and prevents postoperative perianal skin tags formation. Micronized purified flavonoid fraction in the posthemorrhoidectomy period is not associated with additional pain relief in comparison with nonmicronized purified flavonoid fraction standard treatment. See Video Abstract ., Eficacia De La Fraccin De Flavonoides Purificada Micronizada En El Perodo Posterior a La Hemorroidectoma Ensayo Most Ensayo Controlado, Aleatorizado, Abierto: ANTECEDENTES:Una complicación postoperatoria temprana frecuente de la hemorroidectomía es la trombosis y el edema de los "puentes" mucocutáneos.OBJETIVO:Investigamos la eficacia de la fracción de flavonoides purificada micronizada en la prevención de complicaciones después de una hemorroidectomía electiva.DISEÑO:Ensayo controlado aleatorio, prospectivo, unicentral, abierto.AJUSTES:2021-2022 Clínica de Cirugía Colorrectal y Mínimamente Invasiva Universidad Sechenov (Moscú, Rusia).PACIENTES:Pacientes después de hemorroidectomía, que se realizó para hemorroides de grado III-IV.INTERVENCIONES:Después de la hemorroidectomía, los pacientes fueron asignados aleatoriamente al tratamiento estándar (antiinflamatorios no esteroides perorales y anestésicos locales, esteroides tópicos, psyllium, baños de asiento tibios, gel de nifedipina) - grupo de control, o al tratamiento estándar con flavonoide purificado micronizado. fracción (grupo de estudio) y seguido durante 60 días.RESULTADOS DE MEDIDAS PRINCIPALES:Trombosis o edema de puentes mucocutáneos e intensidad del dolor en una escala analógica visual entre el 1.º, 7.º, 14.º, 21.º y 30.º día postoperatorio; calidad de vida y efecto del tratamiento evaluado por el paciente el día 1, 3, 7, 21 y 30 del postoperatorio; Marcas cutáneas perianales en el día 60 del postoperatorio.RESULTADOS:Se analizaron los datos de 50 pacientes (25 en cada grupo). La escala analógica visual no demostró diferencias entre grupos en cada punto de seguimiento. En comparación con el grupo de control, los pacientes en el grupo de estudio tuvieron un efecto del tratamiento evaluado por el paciente significativamente mayor en los días 1, 3, 7, 21 y 30 después de la operación, una tasa significativamente menor de trombosis o edema de los puentes mucocutáneos en los días 1, 7 y 14.. Los pacientes del grupo de estudio tuvieron tasas significativamente más bajas de marcas en la piel perianal.LIMITACIONES:Diseño Unicenter de etiqueta abierta.CONCLUSIONES:La fracción de flavonoides purificada micronizada en el período posterior a la hemorroidectomía es un complemento eficaz del tratamiento estándar que ayuda a reducir la tasa de trombosis y edema de los puentes mucocutáneos, mejora el efecto del tratamiento evaluado por el paciente y previene la formación de marcas cutáneas perianales posoperatorias. La fracción de flavonoides purificados micronizados en el período posterior a la hemorroidectomía no se asocia con un alivio adicional del dolor en comparación con el tratamiento estándar con la fracción de flavonoides purificados no micronizados. (Traducción-Yesenia Rojas-Khalil )., (Copyright © The ASCRS 2024.)

Beneficial properties of lactic acid bacteria have been known long ago, but particular interest in probiotics has arisen in the last two decades due to the understanding of the important role of intestinal microflora in human life. Thus, the ability of probiotics to support healthy homeostasis of gut microbiomes has received particular attention. Here, we evaluated the effect of a probiotic consisting of Bifidobacterium longum and Lacticaseibacillus paracasei on the gut microbiome of male rats, assessed their persistence in the fecal biota, and compared probiotic-mediated changes in vitro and in vivo. As expected, microbiomes of two enterotypes were identified in the feces of 21 animals, and it turned out that even a single dose of the probiotic altered the microbial composition. Upon repeated administration, the E1 biota temporarily acquired properties of the E2 type. Being highly sensitive to the intervention of probiotic bacteria at the phylum and genus levels, the fecal microbiomes retained the identity of their enterotypes when transferred to a medium optimized for gut bacteria. For the E2 biota, even similarities between probiotic-mediated reactions in vitro and in vivo were detected. Therefore, fecal-derived microbial communities are proposed as model consortia to optimize the response of resident bacteria to various agents.