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991.
This review focuses on utilization of plant lectins as medical diagnostic reagents and tools. The lectin-related diagnostic
is aimed at detection of several diseases connected to alteration of the glycosylation profiles of cells and at identification
of microbial and viral agents in clinical microbiology. Certain lectins, proposed for or used as diagnostic tools could even
recognize those cellular determinants, which are not detected by available antibodies. Broad information is presented on the
lectinomics field, illustrating that lectin diagnostics might become practical alternative to antibody-based diagnostic products.
In addition, the rising trend of lectin utilization in biomedical diagnostics might initiate a development of innovative methods
based on better analytical technologies. Lectin microarray, a rapid and simple methodology, can be viewed as an example for
such initiative. This technology could provide simple and efficient screening tools for analysis of glycosylation patterns
in biological samples (cellular extracts, tissues and the whole cells), allowing thus personalized detection of changes associated
with carbohydrate-related diseases. 相似文献
992.
993.
Xylose anaerobic conversion by open-mixed cultures 总被引:1,自引:0,他引:1
Margarida F. Temudo Tania Mato Robbert Kleerebezem Mark C. M. van Loosdrecht 《Applied microbiology and biotechnology》2009,82(2):231-239
Xylose is, after glucose, the dominant sugar in agricultural wastes. In anaerobic environments, carbohydrates are converted
into volatile fatty acids and alcohols. These can be used as building blocks in biotechnological or chemical processes, e.g.,
to produce bioplastics. In this study, xylose fermentation by mixed microbial cultures was investigated and compared with
glucose under the same conditions. The product spectrum obtained with both substrates was comparable. It was observed that,
in the case of xylose, a higher fraction of the carbon was converted into catabolic products (butyrate, acetate, and ethanol)
and the biomass yield was approximately 20% lower than on glucose, 0.16 versus 0.21 Cmol X/Cmol S. This lower yield is likely
related to the need of an extra ATP during xylose uptake. When submitted to a pulse of glucose, the population cultivated
on xylose could instantaneously convert the glucose. No substrate preference was observed when glucose and xylose were fed
simultaneously to the continuously operated bioreactor. 相似文献
994.
Two new species of the genus Quadroppia Jacot, 1939, Quadroppia (Coronoquadroppia) squarrosa sp. n. and Quadroppia (Quadroppia) foveolata sp. n. are described and illustrated from Turkey. They were collected from soil and litter under pear trees (Pyrus communis) and moss on rock, respectively. 相似文献
995.
The chitosan with three-dimensional porous structure greatly increased the effective electrode surface for loading of platinum
nanoparticles and promoted efficient electron transfer. The resulting biosensor had a response time (within 5 s) and a linear
response from 6 μM to 4.2 mM glucose with a detection limit of 2 μM (S/N = 3). Moreover, the methodology can be applied for
the immobilization of other enzymes. 相似文献
996.
Cell migration and growth are essential components of the development of multicellular organisms. The role of various cues
in directing cell migration is widespread, in particular, the role of signals in the environment in the control of cell motility
and directional guidance. In many cases, especially in developmental biology, growth of the domain also plays a large role
in the distribution of cells and, in some cases, cell or signal distribution may actually drive domain growth. There is an
almost ubiquitous use of partial differential equations (PDEs) for modelling the time evolution of cellular density and environmental
cues. In the last 20 years, a lot of attention has been devoted to connecting macroscopic PDEs with more detailed microscopic
models of cellular motility, including models of directional sensing and signal transduction pathways. However, domain growth
is largely omitted in the literature. In this paper, individual-based models describing cell movement and domain growth are
studied, and correspondence with a macroscopic-level PDE describing the evolution of cell density is demonstrated. The individual-based
models are formulated in terms of random walkers on a lattice. Domain growth provides an extra mathematical challenge by making
the lattice size variable over time. A reaction–diffusion master equation formalism is generalised to the case of growing
lattices and used in the derivation of the macroscopic PDEs. 相似文献
997.
Aleksandra Topic Marina Milenkovic Snezana Uskokovic-Markovic Dragana Vucicevic 《Biological trace element research》2010,134(3):296-306
Investigations of effective, orally active, and safe antidiabetic metallopharmaceuticals have been carried out during the
last two decades. It has been reported that tungsten compounds mimic the action of insulin in intact cell systems. As insulin
mimetics, the most investigated tungsten compound was sodium tungstate (ST), rarely investigated was tungstophosphoric acid
(WPA), but never alanine complex of tungstophosphoric acid (WPA-A). In this study, the insulin mimetic activity of three different
tungsten compounds, ST, WPA, and WPA-A, was evaluated by means of in vitro measurements of the glucose uptake and inhibition
of free fatty acids release from epinephrine-treated isolated rat white adipocytes. We investigated the influence of concentration
(lower and higher, 0.1 and 1.0 mM, respectively) and solvent: isotonic salt solution—saline (0.9% w/v of NaCl) and dimethyl sulfoxide (DMSO; 2% v/v), on the biological effect of tested compounds. Our experimental data showed that all of the three investigated tungsten
compounds possess insulin mimetic activity in vitro on the isolated adipocytes. Influence of concentration and solvents on
insulin mimetic effect for the certain tungsten compounds were: WPA was shown effect independently of concentration and solvents;
higher concentration and DMSO were significant decreasing insulin mimetic effect of ST; lower concentration and saline led
to decreasing effect of WPA-A. Generally, there were no differences in insulin mimetic effect of three tungsten compounds
in lower concentration and dissolved in DMSO. When saline was used as solvent, it was needed higher concentration of investigated
compounds to accomplish the same effect. In conclusion, our results suggest that low concentration (0.1 mM) of ST, WPA, and
WPA-A dissolved in 2% DMSO could be the good candidates for in vivo investigation of their antidiabetic properties. 相似文献
998.
Jolanta J. Adamczyk 《Ecological Research》2011,26(3):547-554
Macrofungal communities were investigated in four associations of xerothermic swards: Festucetum pallentis, Origano-Brachypodietum, Adonido-Brachypodietum pinnati and Diantho-Armerietum elongatae in a Jurassic area of the Częstochowa Upland (southern Poland). A total of 47 species were recorded. The self-organising
map (SOM)—an unsupervised algorithm for artificial neural networks—was used to recognise patterns in the macrofungal communities
of diverse xerothermic swards. Only two associations were mycologically similar: Origano-Brachypodietum and Adonido-Brachypodietum pinnati. Species with high and significant IndVal (the species indicator value) for each investigated phytocoenoses are presented.
The presence of macrofungal species and the participation of indicator species were connected with habitat factors of plant
associations, as documented by the IndVal application. In the least fertile phytocoenoses, macrofungal communities were poor
with few indicator species. The more fertile phytocoenoses had richer and more varied communities of macrofungi with higher
numbers of indicator species. The ordering methods applied in this study were very effective for analyzing the macrofungal
communities existing in plant associations. 相似文献
999.
Background
Although capable to evolve, viruses are generally considered non-living entities because they are acellular and devoid of metabolism. However, the recent publication of the genome sequence of the Mimivirus, a giant virus that parasitises amoebas, strengthened the idea that viruses should be included in the tree of life. In fact, the first phylogenetic analyses of a few Mimivirus genes that are also present in cellular lineages suggested that it could define an independent branch in the tree of life in addition to the three domains, Bacteria, Archaea and Eucarya. 相似文献1000.