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1.
Int J Food Sci ; 2021: 6691428, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34631875

RESUMO

Fungi Eurotium spp. are the main biological agents that ferment the leaves of the Camellia sinensis tea bush to form a popular food product, postfermented tea. The fungus E. cristatum, stored in the collection of the Gause Institute of New Antibiotics under the number INA 01267, was isolated and identified from a briquette of Fujian Chinese tea. The species identification was carried out based on morphocultural characteristics and DNA sequencing. This study is aimed at determining the feasibility of making postfermented herbal teas using E. cristatum and to evaluate their quality. Autofermented herbal teas from Chamaenerion angustifolium (fireweed) and Malus domestica (apple tree) served as the starting material for this study. The change in the concentration of phenolic compounds, organic acids, sugars, and free amino acids was observed for herbal teas subjected to postfermentation with E. cristatum INA 01267. It was found that the E. cristatum INA 01267 strain does not have antimicrobial activity and does not form mycotoxins, which is an indicator of food safety.

2.
Ultrastruct Pathol ; 44(2): 227-236, 2020 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-32148147

RESUMO

The phenomenon of unstable expression of gap junction's proteins connexins remains a "visiting card" of astrocytic tumors with various degrees of malignancy. At the same time, it stays unclear what is detected by the positive expression of connexins in astrocytic tumors: gap junctions, hemi-channels, or connexin proteins in cytosol. In the present work, for the first time, we demonstrate an ultrastructural evidence of gap junctions in pleomorphic xanthoastrocytoma, a rare primary brain tumor, the intercellular characteristics of which are poorly studied and remain very discursive and controversial. The primary tumor mass was resected during craniotomy from a 57-old patient diagnosed with pleomorphic xanthoastrocytoma Grade II based on the histopathological analysis. The immunohistochemical study was conducted with primary antibodies: Neurofilament, Myelin basic protein, Glial fibrillary acidic protein, and Synaptophysin. For electron microscopic examination fragments of tumor tissue were fixed in a glutaraldehyde, postfixed in a 1% OsO4, dehydrated and embedded into resin. After the detailed clinical, histological, and immunohistochemical study we revealed some ultrastructural characteristics of the tumor, as well as the first evidence of direct intercellular connection between the tumor cells via gap junctions. Regularly arranged gap junctions connected the somas of xanthastrocytes with dark cytoplasm containing lipid drops. Besides the localization between the cell bodies, from one to several gap junctions were found between the branches of xanthoastrocytoma in tumor intercellular space in close proximity to tumor cell. Our results may indicate gap junctions as a possible structure for intercellular communication between pleomorphic xanthoastrocytoma cells.


Assuntos
Astrocitoma/ultraestrutura , Neoplasias Encefálicas/ultraestrutura , Junções Comunicantes/ultraestrutura , Astrocitoma/patologia , Neoplasias Encefálicas/patologia , Humanos , Masculino , Microscopia Eletrônica de Transmissão , Pessoa de Meia-Idade
3.
Extremophiles ; 24(1): 93-105, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31606813

RESUMO

Ice wedges differ from other types of surface and underground glacial bodies and are widely spread in perennially frozen sub-Arctic regions, but the bacterial and archaeal diversity in these permafrost features remains poorly studied. Here, we compared the prokaryotic community composition in the active layer and ancient, 13-19 kyr BP and ~ 40 kyr BP, ice wedge horizons from the same exposure profile of the Mammoth Mountain, using pyrosequencing 16S rRNA gene. The most abundant OTUs in the active layer were affiliated with Acidobacteria (31.81%) followed by Actinobacteria (18.29%), Proteobacteria (18.14%), Gemmatimonadetes (7.3%), Parcubacteria (7.13%) and Bacteroidetes (6.49%). The prokaryotic community in 13-19 kyr BP ice wedge differed at the phylum level by the predominance of Actinobacteria (29.15%) over Acidobacteria (19.52%), Proteobacteria (18.45%), Verrumicrobia (5.88%), Firmicutes (2.98%) and Gemmatimonadetes (2.87%). In contrast, the oldest (~ 40 kyr BP) ice wedge prokaryotic community was rather poor, and only three phyla Firmicutes (54.48%), Proteobacteria (31.42%) and Bacteroidetes (7.92%) constituted the major fraction of reads. Archaeal sequences contributed with no more than 0.6% to total reads in all studied samples. Apparently, the Mammoth Mountain exposure profile harbors insular microbial communities with specific structure that reflects the stratigraphy, properties and age.


Assuntos
Mamutes , Animais , Archaea , Regiões Árticas , Gelo , Filogenia , RNA Ribossômico 16S , Microbiologia do Solo
4.
Int J Syst Evol Microbiol ; 70(2): 929-934, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31730034

RESUMO

A novel actinobacterium, strain K3-2T, was isolated in pure culture from a thawing ancient ice wedge at Mammoth Mountain (Eastern Siberia, Russia). Colonies of strain K3-2T were yellowish orange; cells had the fine structure typical of Gram-positive bacteria, were non-motile short rods and were non-spore-forming. Strain K3-2T was mesophilic (optimum growth at 28 °Ð¡), but capable of growing at 4 °Ð¡. The cell-wall peptidoglycan of strain K3-2T contained lysine (the diagnostic diamino acid), glutamic acid, alanine, ornithine, glycine and serine. The polar lipids were phosphatidylglycerol, lysophosphatidylserine, three unidentified phospholipids and glycolipids. The major fatty acids were anteiso-C15 : 0 and C16 : 0. The only menaquinone detected was MK-8(H4). 16S rRNA gene analysis indicated that strain K3-2T belongs to the genus Serinibacter. The closest taxonomically described relatives were Serinibacter salmoneus Kis4-28T and Serinibacter tropicus PS-14-7T, with 97.20 and 97.20 % 16 s rRNA gene sequence similarity, respectively. The average nucleotide identity value of the whole genome sequence between strain K3-2T and S. salmoneus Kis4-28T was 78.9 %. DNA-DNA relatedness values between strain K3-2T and S. salmoneus DSM 21801T (=Kis4-28T) and S. tropicus VKPM Ac 2044T (=PS-14-7T) were 41 and 47 %. Thus, strain K3-2T represents a novel species of the genus Serinibacter for which the name Serinibacter arcticus sp. nov. is proposed. The type strain is K3-2T (DSM 103859T=VKM Ас-2719T).


Assuntos
Actinobacteria/classificação , Gelo , Filogenia , Actinobacteria/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , DNA Bacteriano/genética , Ácidos Graxos/química , Glicolipídeos/química , Hibridização de Ácido Nucleico , Peptidoglicano/química , Fosfolipídeos/química , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Sibéria , Vitamina K 2/análogos & derivados , Vitamina K 2/química
5.
NPJ Vaccines ; 2: 17, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29263873

RESUMO

The national blueprint for biodefense concluded that the United States is underprepared for biological threats. The licensed anthrax vaccine absorbed vaccine, BioThrax, requires administration of at least 3-5 intramuscular doses. The anthrax vaccine absorbed vaccine consists of complex cell-free culture filtrates of a toxigenic Bacillus anthracis strain and causes tenderness at the injection site and significant adverse events. We integrated a codon-optimized, protective antigen gene of B. anthracis (plus extracellular secretion machinery), into the chromosome of the licensed, oral, live-attenuated typhoid fever vaccineTy21a to form Ty21a-PA-01 and demonstrated excellent expression of the gene encoding protective antigen. We produced the vaccine in a 10-L fermenter; foam-dried and vialed it, and characterized the dried product. The vaccine retained ~50% viability for 20 months at ambient temperature. Sera from animals immunized by the intraperitoneal route had high levels of anti-protective antigen antibodies by enzyme-linked immunosorbent assay and anthrax lethal toxin-neutralizing activity. Immunized mice were fully protected against intranasal challenge with ~5 LD50 of B. anthracis Sterne spores, and 70% (7/10) of vaccinated rabbits were protected against aerosol challenge with 200 LD50 of B. anthracis Ames spores. There was a significant correlation between protection and antibody levels determined by enzyme-linked immunosorbent assay and toxin-neutralizing activity. These data provide the foundation for achievement of our ultimate goal, which is to develop an oral anthrax vaccine that is stable at ambient temperatures and induces the rapid onset of durable, high-level protection after a 1-week immunization regimen.

6.
Gene ; 636: 48-53, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-28916375

RESUMO

Permanently frozen (approx. 3.5Ma) alluvial Neogene sediments exposed in the Aldan river valley at the Mammoth Mountain (Eastern Siberia) are unique, ancient, and poorly studied permafrost environments. So far, the structure of the indigenous bacterial community has remained unknown. Use of 16S metagenomic analysis with total DNA isolation using DNA Spin Kit for Soil (MO-Bio) and QIAamp DNA Stool Mini Kit (Qiagen) has revealed the major and minor bacterial lineages in the permafrost alluvium sediments. In sum, 61 Operational Taxonomic Units (OTUs) with 31,239 reads (Qiagen kit) and 15,404 reads (Mo-Bio kit) could be assigned to the known taxa. Only three phyla, Bacteroidetes, Proteobacteria and Firmicutes, comprised >5% of the OTUs abundance and accounted for 99% of the total reads. OTUs pertaining to the top families (Chitinophagaceae, Caulobacteraceae, Sphingomonadaceae, Bradyrhizobiaceae, Halomonadaceae) held >90% of reads. The abundance of Actinobacteria was less (0.7%), whereas members of other phyla (Deinococcus-Thermus, Cyanobacteria/Chloroplast, Fusobacteria, and Acidobacteria) constituted a minor fraction of reads. The bacterial community in the studied ancient alluvium differs from other permafrost sediments, mainly by predominance of Bacteroidetes (>52%). The diversity of this preserved bacterial community has the potential to cause effects unknown if prompted to thaw and spread with changing climate. Therefore, this study elicits further reason to study how reintroduction of these ancient bacteria could affect the surrounding ecosystem, including current bacterial species.


Assuntos
Bactérias/isolamento & purificação , Pergelissolo/microbiologia , Bactérias/classificação , Bactérias/genética , Sedimentos Geológicos/química , Sedimentos Geológicos/microbiologia , Metagenômica , RNA Ribossômico 16S/genética , Sibéria
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