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81.
The possibility of cultivation of fungi on sugar cane waste (leaves and stalk tops) was tested. Having been crushed, macerated and heated, this material becomes a suitable substrate for cultivation of oyster mushrooms. Selected hybrids ofPleurotus ostreatus × P. ostreatus form Florida rapidly colonized the substrate and, in the first phase, yielded more than 10% of fresh fruiting bodies per initial mass of the wet substrate, which is considered, to be the efficiency limit of this technology. The growth cycle in Cuba is shorter than in Europe. Under the tested temperature and light conditions in Cuba, all strains formed white fruiting bodies, as compared to a multicolored variety developed in Czechoslovakia. Some of the newly obtained hybrids were found to have better properties than the original production strains. Hybrids of Cuban origin should be prepared. Besides common, well-known pests, several species of ants damage the cultures of oyster mushrooms. Translated by Č. Novotny  相似文献   
82.

Objectives

Osteoarthritis (OA) is a chronic joint disease, characterized by a progressive loss of articular cartilage. During OA, proinflammatory cytokines, such as interleukin IL-1, induce the expression of matrix metalloproteinases (MMPs) in chondrocytes, contributing thus to the extracellular matrix (ECM) degradation. Members of Serpine family, including plasminogen activator inhibitors have been reported to participate in ECM regulation. The aim of this study was to assess the expression of serpin peptidase inhibitor clade E member 2 (SERPINE2), under basal conditions and in response to increasing doses of IL-1α, in human cultured chondrocytes. We also examined the effects of SERPINE2 on IL-1α-induced MMP-13 expression. For completeness, the signaling pathway involved in this process was also explored.

Methods

SERPINE2 mRNA and protein expression were evaluated by RT-qPCR and western blot analysis in human T/C-28a2 cell line and human primary chondrocytes. These cells were treated with human recombinant SERPINE2, alone or in combination with IL-1α. ERK 1/2, NFκB and AP-1 activation were assessed by western blot analysis.

Results

Human cultured chondrocytes express SERPINE2 in basal condition. This expression increased in response to IL-1α stimulation. In addition, recombinant SERPINE2 induced a clear inhibition of MMP-13 expression in IL-1α-stimulated chondrocytes. This inhibitory effect is likely regulated through a pathway involving ERK 1/2, NF-κB and AP-1.

Conclusions

Taken together, these data demonstrate that SERPINE2 might prevent cartilage catabolism by inhibiting the expression of MMP-13, one of the most relevant collagenases, involved in cartilage breakdown in OA.  相似文献   
83.
Surface Antigens of Smooth Brucellae   总被引:27,自引:2,他引:27  
Surface antigens of smooth brucellae were extracted by ether-water, phenol-water, trichloroacetic acid, and saline and examined by immunoelectrophoresis and gel diffusion with antisera from infected and immunized rabbits. Ether-water extracts of Brucella melitensis contained a lipopolysaccharide protein component, which was specific for the surface of smooth brucellae and was correlated with the M agglutinogen of Wilson and Miles, a polysaccharide protein component devoid of lipid which was not restricted to the surface of smooth brucellae and was not correlated with the smooth agglutinogen (component 1), and several protein components which were associated with internal antigens of rough and smooth brucellae. Immunoelectrophoretic analysis of ether-water extracts of B. abortus revealed only two components, a lipopolysaccharide protein component, which was correlated with the A agglutinogen, and component 1. Component 1 from B. melitensis and B. abortus showed identity in gel diffusion tests, whereas component M from B. melitensis and component A from B. abortus showed partial identity with unabsorbed antisera and no cross-reactions with monospecific sera. Attempts to prepare monospecific sera directly by immunization of rabbits with cell walls or ether-water extracts were unsuccessful. Absorption of antisera with heavy fraction of ether-water extracts did not always result in monospecific sera. It was concluded (as has been described before) that the A and M antigens are present on a single antigenic complex, in different proportions depending upon the species and biotype, and that this component is a lipopolysaccharide protein complex of high molecular weight that diffuses poorly through agar gel. Components 1, A, and M were also demonstrated in trichloroacetic acid and phenol-water extracts. With all extracts, B. melitensis antigen showed greater diffusibility in agar than B. abortus antigens. After mild acid hydrolysis, B. abortus ether-water extract was able to diffuse more readily.  相似文献   
84.
The cyclin-dependent kinase Cdk1 directly regulates vacuole inheritance   总被引:1,自引:0,他引:1  
In budding yeast, vacuole inheritance is tightly coordinated with the cell cycle. The movement of vacuoles and several other organelles is actin-based and is mediated by interaction between the yeast myosin V motor Myo2 and organelle-specific adaptors. Myo2 binds to vacuoles via the adaptor protein Vac17, which binds to the vacuole membrane protein Vac8. Here we show that the yeast cyclin-dependent kinase Cdk1 phosphorylates Vac17 and that phosphorylation of Vac17 parallels cell cycle-dependent movement of the vacuole. Substitution of the Cdk1 sites in Vac17 decreases its interaction with Myo2 and causes a partial defect in vacuole inheritance. This defect is enhanced in the presence of Myo2 with mutated phosphorylation sites. Thus, Cdk1 appears to control the timing of vacuole movement. The presence of multiple predicted Cdk1 sites in other organelle-specific myosin V adaptors suggests that the inheritance of other cytoplasmic organelles may be regulated by a similar mechanism.  相似文献   
85.
The deoxyribonucleic acid (DNA) polymerase of Rous sarcoma virus synthesizes both single- and double-stranded DNA, utilizing the ribonucleic acid (RNA) of the viral genome as the initial template. Results of pulse-chase experiments indicate that the single-stranded DNA serves as unconserved template and precursor for the synthesis of double-stranded DNA. The latter reaction is apparently initiated in association with the viral RNA and may involve a partially double-stranded intermediate form.  相似文献   
86.
The Azorean barnacle, Megabalanus azoricus (Pilsbry, 1916), is a Macaronesian endemic whose obscure taxonomy and the unknown relationships among forms inhabiting isolated Northern Atlantic oceanic islands is investigated by means of molecular analysis herein. Mitochondrial data from the 16S rRNA and COX1 genes support its current species status, tropical ancestry, and the taxonomic homogeneity throughout its distribution range. In contrast, at the intraspecific level and based on control region sequences, we detected an overall low level of genetic diversity and three divergent lineages. The haplogroups α and γ were sampled in the Azores, Madeira, Canary, and Cabo Verde archipelagos; whereas haplogroup β was absent from Cabo Verde. Consequently, population analysis suggested a differentiation of the Cabo Verde population with respect to the genetically homogenous northern archipelagos generated by current oceanographic barriers. Furthermore, haplogroup α, β, and γ demographic expansions occurred during the interglacial periods MIS5 (130 Kya - thousands years ago -), MIS3 (60 Kya), and MIS7 (240 Kya), respectively. The evolutionary origin of these lineages is related to its survival in the stable southern refugia and its demographic expansion dynamics are associated with the glacial-interglacial cycles. This phylogeographic pattern suggests the occurrence of genetic discontinuity informative to the delimitation of an informally defined biogeographic entity, Macaronesia, and its generation by processes that delineate genetic diversity of marine taxa in this area.  相似文献   
87.
Enzymes in culture filtrates of Rhizoctonia solani Kuhn grown using 4-day old or 20-day old bean (Phaseolus vulgaris L.) hypocotyl cell walls as a carbon source degraded xylan, galactan, galactomannan, araban, polygalacturonic acid, and carboxymethylcellulose. Extracts of lesions from R. solani infected plants, but not healthy plants, contained similar enzymatic activities. These enzyme sources readily solubilized cell wall constituents containing arabinose, galactose, and glucose from 4-day old, but not from 20-day old, bean cell walls. Analysis of cell walls prepared from infected plants revealed that the alterations in cell wall composition in the diseased host were limited largely to the immediate lesion areas and occurred during the early phases of pathogenesis. The cell walls of young susceptible bean seedlings could be degraded by R. solani enzymes, but the cell walls of older plants which are resistant to this pathogen were not susceptible to enzymatic destruction by the same enzyme preparation.  相似文献   
88.
As the volume of data relating to proteins increases, researchers rely more and more on the analysis of published data, thus increasing the importance of good access to these data that vary from the supplemental material of individual articles, all the way to major reference databases with professional staff and long‐term funding. Specialist protein resources fill an important middle ground, providing interactive web interfaces to their databases for a focused topic or family of proteins, using specialized approaches that are not feasible in the major reference databases. Many are labors of love, run by a single lab with little or no dedicated funding and there are many challenges to building and maintaining them. This perspective arose from a meeting of several specialist protein resources and major reference databases held at the Wellcome Trust Genome Campus (Cambridge, UK) on August 11 and 12, 2014. During this meeting some common key challenges involved in creating and maintaining such resources were discussed, along with various approaches to address them. In laying out these challenges, we aim to inform users about how these issues impact our resources and illustrate ways in which our working together could enhance their accuracy, currency, and overall value. Proteins 2015; 83:1005–1013. © 2015 The Authors. Proteins: Structure, Function, and Bioinformatics Published by Wiley Periodicals, Inc.  相似文献   
89.
The tify family previously known as ZIM   总被引:6,自引:0,他引:6  
The ZIM domain was originally identified in the ZIM protein (BAA97679; Zinc-finger protein expressed in Inflorescence Meristem). Since then it has been found in other proteins and the corresponding genes have been grouped into a plant-specific family. However, the family lacks consistency in its classification among different databases. Here, we try to clarify this incongruity by presenting an overview of the Arabidopsis proteins having this domain. The presented genome-wide survey can be seen as a start point to reveal the unknown function of these proteins. Furthermore, because of the confusing ZIM nomenclature being used at present, we propose to rename the domain and family as tify, after the most conserved amino acid motif characterizing the members of this family.  相似文献   
90.
Endometrial secretions in the uterine cavity contain mediators important for endometrial receptivity and embryo implantation. Unbiased analysis of uterine fluid from a receptive versus nonreceptive time of the menstrual cycle and in fertile and infertile women will provide new insights into uterine receptivity. We hypothesized that proteomic analysis of human uterine lavages would identify proteins important for the establishment of pregnancy in humans. Lavages collected from fertile (n = 7) and infertile (n = 8) women during the midsecretory (MS) phase, and from fertile women during the midproliferative (MP) (n = 7) phase, were assessed using 2D-differential in gel electrophoresis (2D-DiGE) over a pI 4-7 range. Statistical analysis revealed 7 spots that were significantly decreased in the MP compared to the MS phase, while 18 spots showed differential expression between fertile and infertile women. A number of proteins were identified by mass spectrometry, including antithrombin III and alpha-2-macroglobulin, whose production was confirmed in endometrial epithelium. Their staining pattern suggests roles during embryo implantation. Assessment of the human endometrial secretome has identified differences in the protein content of uterine fluid with respect to receptivity and fertility.  相似文献   
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