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991.
992.
993.
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
994.
Pleiotropic recessive mutation glass-like (gl-l) found in region 8C10–8E of the X chromosome was shown to cause glass-like eyes having no boundaries between facets and a nonuniform pigment distribution determined by the endogenous white. The gl-lmutation completely inhibited expression of the mini-white transgene contained in several constructs, but the effect depended on the site of construct insertion in the genome. The mutation had no effect on the expression of the white transgene having the enhancer and flanked by insulators. The gl-l mutation did not affect the extent of mosaic eye pigmentation when a construct with mini-white was inserted in the telomeric or pericentric region. However, in most cases it completely inhibited the mosaic mini-white expression when cloned heterochromatic repeats were adjacent to the reporter gene in a construct. The gl-l gene was assumed to play a role in the formation of the chromatin structure, because the effect of its mutation on expression of the white transgene depended on the transgene insertion site, the presence of insulators or an enhancer in the vicinity of the transgene, and on the adjacent heterochromatic repeats. 相似文献
995.
996.
Chao Liu An-Song Liu Da Zhong Cheng-Gong Wang Mi Yu Hao-Wei Zhang Han Xiao Jian-Hua Liu Jian Zhang Ke Yin 《Cell death & disease》2021,12(7)
Bone marrow-derived mesenchymal stem cells (BM-MSCs), the common progenitor cells of adipocytes and osteoblasts, have been recognized as the key mediator during bone formation. Herein, our study aim to investigate molecular mechanisms underlying circular RNA (circRNA) AFF4 (circ_AFF4)-regulated BM-MSCs osteogenesis. BM-MSCs were characterized by FACS, ARS, and ALP staining. Expression patterns of circ_AFF4, miR-135a-5p, FNDC5/Irisin, SMAD1/5, and osteogenesis markers, including ALP, BMP4, RUNX2, Spp1, and Colla1 were detected by qRT-PCR, western blot, or immunofluorescence staining, respectively. Interactions between circ_AFF4 and miR-135a-5p, FNDC5, and miR-135a-5p were analyzed using web tools including TargetScan, miRanda, and miRDB, and further confirmed by luciferase reporter assay and RNA pull-down. Complex formation between Irisin and Integrin αV was verified by Co-immunoprecipitation. To further verify the functional role of circ_AFF4 in vivo during bone formation, we conducted animal experiments harboring circ_AFF4 knockdown, and born samples were evaluated by immunohistochemistry, hematoxylin and eosin, and Masson staining. Circ_AFF4 was upregulated upon osteogenic differentiation induction in BM-MSCs, and miR-135a-5p expression declined as differentiation proceeds. Circ_AFF4 knockdown significantly inhibited osteogenesis potential in BM-MSCs. Circ_AFF4 stimulated FNDC5/Irisin expression through complementary binding to its downstream target molecule miR-135a-5p. Irisin formed an intermolecular complex with Integrin αV and activated the SMAD1/5 pathway during osteogenic differentiation. Our work revealed that circ_AFF4, acting as a sponge of miR-135a-5p, triggers the promotion of FNDC5/Irisin via activating the SMAD1/5 pathway to induce osteogenic differentiation in BM-MSCs. These findings gained a deeper insight into the circRNA-miRNA regulatory system in the bone marrow microenvironment and may improve our understanding of bone formation-related diseases at physiological and pathological levels.Subject terms: Stem cells, Diseases 相似文献
997.
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
998.
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
999.
Tayvich Vorapreeda Chinae Thammarongtham Kobkul Laoteng 《World journal of microbiology & biotechnology》2016,32(7):122
Lipid-degrading or lipolytic enzymes have gained enormous attention in academic and industrial sectors. Several efforts are underway to discover new lipase enzymes from a variety of microorganisms with particular catalytic properties to be used for extensive applications. In addition, various tools and strategies have been implemented to unravel the functional relevance of the versatile lipid-degrading enzymes for special purposes. This review highlights the study of microbial lipid-degrading enzymes through an integrative computational approach. The identification of putative lipase genes from microbial genomes and metagenomic libraries using homology-based mining is discussed, with an emphasis on sequence analysis of conserved motifs and enzyme topology. Molecular modelling of three-dimensional structure on the basis of sequence similarity is shown to be a potential approach for exploring the structural and functional relationships of candidate lipase enzymes. The perspectives on a discriminative framework of cutting-edge tools and technologies, including bioinformatics, computational biology, functional genomics and functional proteomics, intended to facilitate rapid progress in understanding lipolysis mechanism and to discover novel lipid-degrading enzymes of microorganisms are discussed. 相似文献
1000.
Nikhil Ram-Mohan Aharon Oren R. Thane Papke 《Extremophiles : life under extreme conditions》2016,20(5):747-757
Stability of microbial communities can impact the ability of dispersed cells to colonize a new habitat. Saturated brines and their halophile communities are presumed to be steady state systems due to limited environmental perturbations. In this study, the bacteriorhodopsin-containing fraction of the haloarchaeal community from Eilat salt crystallizer ponds was sampled five times over 3 years. Analyses revealed the existence of a constant core as several OTUs were found repeatedly over the length of the study: OTUs comprising 52 % of the total cloned and sequenced PCR amplicons were found in every sample, and OTUs comprising 89 % of the total sequences were found in more than one, and often more than two samples. LIBSHUFF and UNIFRAC analyses showed statistical similarity between samples and Spearman’s coefficient denoted significant correlations between OTU pairs, indicating non-random patterns in abundance and co-occurrence of detected OTUs. Further, changes in the detected OTUs were statistically linked to deviations in salinity. We interpret these results as indicating the existence of an ever-present core bacteriorhodopsin-containing Eilat crystallizer community that fluctuates in population densities, which are controlled by salinity rather than the extinction of some OTUs and their replacement through immigration and colonization. 相似文献