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1.
Orig Life Evol Biosph ; 47(2): 169-185, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27025932

RESUMO

Biofilm-forming microbial communities are known as the most robust assemblages that can survive in harsh environments. Biofilm-associated microorganisms display greatly increased resistance to physical and chemical adverse conditions, and they are expected to be the first form of life on Earth or anywhere else. Biological molecules synthesized by biofilm -protected microbiomes may serve as markers of the nucleoprotein life. We offer a new experimental model, a kombucha multimicrobial culture (KMC), to assess a structural integrity of a widespread microbial polymer - cellulose - as a biosignature of bacteria-producers for the multipurpose international project "BIOlogical and Mars Experiment (BIOMEX)", which aims to study the vitality of pro- and eukaryotic organisms and the stability of organic biomolecules in contact with minerals to analyze the detectability of life markers in the context of a planetary background. In this study, we aimed to substantiate the detectability of mineralized cellulose with spectroscopy and to study the KMC macrocolony phenotype stability under adverse conditions (UV, excess of inorganics etc.). Cellulose matrix of the KMC macrocolony has been mineralized in the mineral-water interface under assistance of KMC-members. Effect of bioleached ions on the cellulose matrix has been visible, and the FT-IR spectrum proved changes in cellulose structure. However, the specific cellulose band vibration, confirming the presence of ß(1,4)-linkages between monomers, has not been quenched by secondary minerals formed on the surface of pellicle. The cellulose-based KMC macrocolony phenotype was in a dependence on extracellular matrix components (ionome, viriome, extracellular membrane vesicles), which provided its integrity and rigidness in a certain extent under impact of stressful factors.


Assuntos
Bactérias , Biofilmes , Microbiota , Celulose , Meio Ambiente Extraterreno , Espectroscopia de Infravermelho com Transformada de Fourier
2.
Exp Oncol ; 35(2): 83-8, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23828380

RESUMO

AIM: Development of carbon enterosorbents with optimal physical-chemical properties and high adsorptive capacity for their usage in the treatment of paraneoplastic syndrome and other endogenous intoxication in cancer patients. METHODS: physical-chemical and biochemical methods of investigation. RESULTS: In the work it has been shown that performance of additional steam activation on pilot plant developed in R.E. Kavetsky Institute of Experimental Pathology, Oncology and Radiobiology NAS of Ukraine, allows produce highly active granulated and fibrous carbon enterosorbents which possess well developed porous surface providing potent sorption potential toward compounds of hydrophilic and hydrophobic nature. Being placed in gastro-intestinal tract lumen these sorbents may cause certain effect on functional activity of detoxifying body systems and regeneration potential of many organs and tissues. CONCLUSION: The usage of carbon enterosorbents with optimal physical-chemical properties and high adsorptive capacity could be very perspective for correction of biochemical, immunologic, morphologic and hematological manifestations of paraneoplastic syndrome.


Assuntos
Carbono , Enteroadsorção/métodos , Síndromes Paraneoplásicas/terapia , Adsorção , Bilirrubina/química , Corantes/química , Doxorrubicina/química , Humanos , Interações Hidrofóbicas e Hidrofílicas , Porosidade , Albumina Sérica/química , Propriedades de Superfície
3.
Tsitol Genet ; 41(1): 30-5, 2007.
Artigo em Ucraniano | MEDLINE | ID: mdl-17427415

RESUMO

The effects of microgravity and ethylene on morphology and ultrastructural organization of mitochondria in root statocytes of soybean seedlings grown for 6 days on the board of the space shuttle Columbia during the STS-87 mission were investigated. The spaceflight seedlings and the ground-grown control seedlings were grown in BRIG (Biological Research in Canister) in the presence of KMnO4 to remove ethylene. It was revealed that irrespectively of KMnO4 treatment the mitochondria in the spaceflight seedlings were characterized by round or oviform and by low electron density of organelle matrix, whereas the organelles in the ground controls were polymorphic in shape and had higher electron density of matrix. The possible mechanisms of morphological and ultrastructural rearrangements of mitochondria that may be involved in adaptation processes of soybean seedlings to microgravity conditions are discussed.


Assuntos
Glycine max/crescimento & desenvolvimento , Mitocôndrias/ultraestrutura , Astronave , Ausência de Peso , Etilenos , Microscopia Eletrônica , Mitocôndrias/efeitos dos fármacos , Tamanho Mitocondrial/efeitos dos fármacos , Coifa/efeitos dos fármacos , Coifa/crescimento & desenvolvimento , Coifa/ultraestrutura , Permanganato de Potássio/farmacologia , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Plântula/ultraestrutura , Glycine max/efeitos dos fármacos , Glycine max/ultraestrutura
4.
Adv Space Res ; 31(10): 2283-8, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14686444

RESUMO

Changes in the vacuolation in root apex cells of soybean (Glycine max L. [Merr.]) seedlings grown in microgravity were investigated. Spaceflight and ground control seedlings were grown in the absence or presence of KMnO4 (to remove ethylene) for 6 days. After landing, in order to study of cell ultrastructure and subcellular free calcium ion distribution, seedling root apices were fixed in 2.5% (w/v) glutaraldehyde in 0.1 M cacodylate buffer and 2% (w/v) glutaraldehyde, 2.5% (w/v) formaldehyde, 2% (w/v) potassium antimonate K[Sb(OH)6] in 0.1 M K2HPO4 buffer with an osmolarity (calculated theoretically) of 0.45 and 1.26 osmol. The concentrations of ethylene in all spaceflight canisters were significantly higher than in the ground control canisters. Seedling growth was reduced in the spaceflight-exposed plants. Additionally, the spaceflight-exposed plants exhibited progressive vacuolation in the root apex cells, particularly in the columella cells, to a greater degree than the ground controls. Plasmolysis was observed in columella cells of spaceflight roots fixed in solutions with relatively high osmolarity (1.26 osmol). The appearance of plasmolysis permitted the evaluation of the water status of cells. The water potential of the spaceflight cells was higher than the surrounding fixative solution. A decrease in osmotic potential and/or an increase in turgor potential may have induced increases in cell water potential. However, the plasmolysed (i.e. non-turgid) cells implied that increases in water potential were accompanied with a decrease in osmotic potential. In such cells changes in vacuolation may have been involved to maintain turgor pressure or may have been a result of intensification of other vacuolar functions like digestion and storage.


Assuntos
Glycine max/ultraestrutura , Coifa/ultraestrutura , Plântula/ultraestrutura , Voo Espacial , Vacúolos/fisiologia , Ausência de Peso , Cálcio/metabolismo , Relação Dose-Resposta a Droga , Etilenos/metabolismo , Microscopia Eletrônica , Pressão Osmótica , Reguladores de Crescimento de Plantas/metabolismo , Coifa/efeitos dos fármacos , Coifa/crescimento & desenvolvimento , Coifa/metabolismo , Permanganato de Potássio/farmacologia , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Glycine max/efeitos dos fármacos , Glycine max/crescimento & desenvolvimento , Glycine max/metabolismo
5.
Adv Space Res ; 27(5): 967-72, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11596641

RESUMO

The antimonate precipitation technique was used to evaluate the effects of microgravity and ethylene on the cellular and subcellular distribution of free calcium ions in soybean root apices. Soybean (Glycine max L. [Merr.]) dry seeds were launched, activated by hydration, and germinated in the presence of KMnO4 (to remove ethylene) and in its absence onboard the space shuttle Columbia during the STS-87 mission. Primary root apices of 6-day old seedlings were fixed for electron microscopy after landing. Ultrastructural studies indicated that antimonate precipitation appeared as individual electron-dense particles which were more or less round in shape and varied in diameter from 10 nm (minimum size beginning from which the particles were well identified) to 90 nm. It was revealed that analyzed root cap cells varied in both the precipitate particle sizes and the amount particles per unit of the cellular area. In both flight and ground control treatments, antimonate precipitation level increases from apical meristem cells to peripheral (secretory) cells of root apices. In root cap statocytes, subcellular localization of precipitate particles was revealed in the cytoplasm, nucleus and small vacuoles. The quantitative analysis showed a reduction of precipitate density in the cytoplasm and the nucleus, and an increase in precipitate density in the vacuoles from statocytes of both spaceflight treatments in comparison with ground controls.


Assuntos
Cálcio/metabolismo , Glycine max/metabolismo , Coifa/ultraestrutura , Voo Espacial , Ausência de Peso , Antimônio/farmacologia , Núcleo Celular/metabolismo , Núcleo Celular/ultraestrutura , Precipitação Química , Citoplasma/metabolismo , Citoplasma/ultraestrutura , Etilenos/antagonistas & inibidores , Meristema/metabolismo , Meristema/ultraestrutura , Microscopia Eletrônica , Coifa/metabolismo , Plastídeos/metabolismo , Plastídeos/ultraestrutura , Glycine max/ultraestrutura , Vacúolos/metabolismo , Vacúolos/ultraestrutura
6.
J Gravit Physiol ; 7(2): P79-80, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12697564

RESUMO

Phytoferritin is an iron-protein complex analogous to the ferritin found in mammalian, bacteria and fungi cells. Phytoferritin molecules are large proteins, about 10.5 nm in diameter, visualised in an electron microscope as discrete, electron dense particles with iron-containing core, where several thousand atoms of iron lie within the proteinaceous shell (apoferritin). In higher plants, a plastid stroma is the site of phytoferritin storage. Phytoferritin is seen in all types of plastids. It is considered to be a mechanism used by cells to store iron in a non-toxic form. Phytoferritin-bound iron may subsequently be used to form iron-containing components. It was shown that low levels of phytoferritin are synthesised in normal green leaves, whereas chlorotic leaves do not have a measurable amount of phytoferritin and leaves of iron-loaded seedlings contain a high level of total iron, and phytoferritin well-filled by iron. Phytoferritin accumulation was observed in photosynthetic inactivity chloroplasts during senescence and disease. In this study we analised the effects of microgravity and ethylene on production of phytoferritin in the root cap columella cells of soybean seedlings.


Assuntos
Ferritinas/metabolismo , Glycine max/metabolismo , Coifa/metabolismo , Voo Espacial , Ausência de Peso , Etilenos/farmacologia , Ferritinas/efeitos dos fármacos , Organelas/metabolismo , Reguladores de Crescimento de Plantas/farmacologia , Coifa/efeitos dos fármacos , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/metabolismo , Plastídeos/metabolismo , Glycine max/efeitos dos fármacos
7.
J Gravit Physiol ; 6(1): P97-8, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11543045

RESUMO

Root apex cells of higher plants have unique structure and functions. In particular, the central cells of root cap are considered as the site of gravity perception in roots and are characterised by structural polarity, including directional sedimentation of amyloplasts with to gravity. Past studies have shown that root growth, structural organisation of the cells, and structural polarity of statocytes were affected in microgravity. Microgravity-grown plants also exhibited enhanced production of ethylene and decreased production of starch relative to ground controls. In this paper, the effects of microgravity and ethylene on ultrastructural organisation of the cells in soybean root apices are presented.


Assuntos
Glycine max/ultraestrutura , Coifa/ultraestrutura , Voo Espacial , Ausência de Peso , Microscopia Eletrônica , Coifa/metabolismo , Raízes de Plantas/citologia , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/ultraestrutura , Brotos de Planta , Plastídeos/fisiologia , Plastídeos/ultraestrutura , Glycine max/citologia , Glycine max/crescimento & desenvolvimento , Amido/metabolismo , Vacúolos/fisiologia
8.
J Gravit Physiol ; 5(1): P147-8, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11542330

RESUMO

Establishing the role of gravity in plant requires information about how gravity regulates the metabolism of individual cells. Plant cells and tissues in vitro are valuable models for such purpose. Disrupted intercellular relations in such models have allowed to elucidate both the gravity role in non-specialised to gravity plant cells and the correlative relation role of an intact plant organism. The data obtained from non-numerous space and clinostat experiments with plant cells in vitro have demonstrated that their metabolism is sensitive to g-environment. The most experiments have shown a decrease in the biomass production and cell proliferation of spaceflight samples compared with ground controls, although there is study reporting of increased biomass production in an anise suspension culture and D. carota crown gall tissue culture. At the same time, results of experiments with single carrot cells and tomato callus culture demonstrated similarities in differentiation process in microgravity and in ground controls. Noted ultrastructural arrangement in cells, especially mitochondria and plastids, have been related to altered energy load and functions of organelles in microgravity, as well as changes in the lipid peroxidation and the content of malonic dyaldehyde in a haplopappus tissue culture under altered gravity supposed with modification of membrane structural-functional state. This article focuses on growth aspects of the cultured cells in microgravity and under clinostat conditions and considers those aspects that require further analysis.


Assuntos
Biomassa , Gravitação , Sensação Gravitacional/fisiologia , Voo Espacial , Simulação de Ausência de Peso , Ausência de Peso , Asteraceae/citologia , Asteraceae/crescimento & desenvolvimento , Células Cultivadas , Técnicas de Cultura , Pisum sativum/citologia , Pisum sativum/crescimento & desenvolvimento , Rotação
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