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11.
Ohri SS Vashishta A Vetvickova J Fusek M Vetvicka V 《International journal of biological macromolecules》2007,41(2):204-209
Procathepsin D (pCD) is a glycoprotein secreted abundantly by cancerous cells with a documented role in tumor development. The levels of pCD in primary tumors are highly correlated with an increased incidence of metastasis. Our earlier studies have shown that pCD exerts its effect on cancer cells through its activation peptide (AP) and involves both autocrine and paracrine modes of action. In this study, we analyzed the expression and role of pCD in MDA-MB-231 and its derived cell lines 1833 and 4175 possessing discrete metastatic abilities. Our results demonstrated a direct relationship between expression and secretion of pCD to the differential invasive potential of these cells. Also, the cell lines responded to AP treatment by enhancing their invasive potential, proliferation and induction of secretion of various cytokines, suggesting that pCD plays a role in metastasis through its AP region. 相似文献
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Acarus siro L. 1758 (Acari: Acaridida: Acarididae) is an important pest of stored grain because it contaminates the grain by allergens and transfers pathogenous microorganisms. Rapid detection of contamination enables to intercept an early grain infestation by the pest. In this study, we compared the usability and efficiency of various detection approaches. Under laboratory conditions, grain samples of various sizes were infested by different levels of the following contaminants: eggs, adults, and feces of A. siro. The samples were analyzed by enzyme-linked immunosorbent assay (ELISA) by using anti-A. siro polyclonal antibody (immunochemical method), extracted in Berlese-Tullgren funnels, sieved, and processed by filth-flotation (conventional methods). The adults or juveniles of A. siro could be detected by all the three tested conventional methods and ELISA with detection limits in the range from 221 to 1,157 mites/kg grain. Eggs were detected by filth-flotation only; the detection limit was 1,950 eggs/kg grain. The feces of A. siro were detectable by ELISA test, only. ELISA enabled the detection of the feces with the minimal threshold level of 1.04 microg feces/g grain; it means the assay allowed to trace less than one metabolically active mite per gram of grain. The study thus demonstrated that reliable A. siro detection in grain can only be achieved by combining different detection methods. European Union and U.S. administratives dictate zero or near-zero tolerance level for mite infestation in stored products. This demand is difficult to fulfill, because every detection method is limited by its detection limit; thus, it is hard to reliably detect infestation levels lower than obtained detection limits. This methodical limitation is discussed in context with the determined detection limits of the tested methods. 相似文献
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Vetvicka V Vetvickova J 《Biomedical papers of the Medical Faculty of the University Palacky, Olomouc, Czechoslovakia》2007,151(2):225-231
Background: Numerous types of glucans have been isolated from almost every species of yeast, grain, and fungi. These products have been extensively studied for their immunological and pharmacological effects. Aim: In this paper we evaluated the possibility whether individual glucans will be similarly active against each of the tested biological properties or if each glucan will affect different reactions. Methods: Immunological effects of glucans were measured by evaluation of phagocytosis of HEMA particles by peripheral blood leukocytes and production of IL-2 by mouse splenocytes. Next we measured the effects of long-term treatment with glucan on levels of blood glucose and blood cholesterol. Four different glucans differing in origin (yeast, grain and mushroom) were used. Results: Our results showed that the same glucan, yeast-derived insoluble #300 glucan, stimulated phagocytosis of peripheral blood leukocytes, production of IL-2 by mouse splenocytes, lowered the cholesterol levels in mice with experimentally-induced cholesterolemia and lowered the level of blood sugar after induced hyperglycaemie. The remainder of tested glucans were only marginally active. Conclusion: Taken together, our study showed that with respect to natural glucans, there is a yes-or-no effect suggesting that highly purified and highly active glucans will have pleiotropic impact, whereas poorly isolated and/or less active glucans will have only mediocre biological properties. 相似文献
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Szotkowski T Szotkowska R Pikalova Z Tichy T Flodr P Tichy M Houserkova D Benysek V Zlamalova N Ruzicka V Indrak K 《Biomedical papers of the Medical Faculty of the University Palacky, Olomouc, Czechoslovakia》2007,151(1):113-116
BACKGROUND: Spontaneous splenic rupture (SSR) is a very rare complication described in several hundred patients, mainly as case reports. It is defined as a splenic rupture without antecedent injury. The authors of the present paper describe the only two SSR cases diagnosed at the Hemato-oncology department, coincidentally in one year. PATIENTS: The first patient was admitted to hospital because of planned chemotherapy for relapsed hairy cell leukemia. The second was directed to the Hemato-oncology outpatient department because of anemia and painful splenomegaly diagnosed by a physician. The diagnose of hematologic malignancy (diffuse large B-cell lymphoma) was determined subsequently on the basis of histological examination of the spleen. CONCLUSION: It is necessary to consider SSR not only in patients with known diagnosis of malignant disease but in the patients with negative anamnesis, too. The aim of the paper is to draw attention to the existence of this complication. 相似文献
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Small reducing and linear oligo-beta-(1,3)-glucans, which are able to act as phytoallexin elicitors or as immunostimulating agents in anticancer therapy, were synthesized according to an iterative strategy that involved a unique key monosaccharidic donor. To avoid anomeric mixtures, the reducing entity of the target oligomers was first locked with benzyl alcohol and further selective deprotection of the 3-OH with DDQ afforded the desired building block as an acceptor. The latter was then used in a second cycle of glycosylation/deprotection to afford the desired disaccharide, and successive reiterations of this process provided the desired oligomers. Unusual conformational behaviors were observed by standard NMR sequences and supported by NOESY studies. Finally, removal of protecting groups afforded free tri-, tetra-, and pentaglucosides in good overall yields. Two oligosaccharides representing linear laminaritetraose and laminaripentaose were compared to the recently described beta-(1,3)-glucan phycarine. Following an intraperitoneal injection, the influx of monocytes and granulocytes into the blood and macrophages into the peritoneal cavity was comparable to that caused by phycarine. Similarly, both oligosaccharides stimulated phagocytic activity of granulocytes and macrophages. Using ELISA, we also demonstrated a significant stimulation of secretion of IL-1beta. Together these results suggest that the synthetic oligosaccharides have similar stimulatory effects as natural beta-(1,3)-glucans. 相似文献
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Denaturing RNA electrophoresis in TAE agarose gels 总被引:1,自引:0,他引:1
Current methods of analytical RNA electrophoresis are based on the utilization of either complicated laboratory instrumentation or toxic, carcinogenic, or expensive chemicals. We suggest here the use of classical Tris-acetate-ethylenediamine tetraacetic acid (TAE) agarose gels combined with prior denaturation of RNA samples in hot formamide for the electrophoretic separation of RNA species. We present a brief comparison of the proposed TAE/formamide method with the most common 3-(N-morpholino)propanesulfonic acid/formaldehyde agarose gel protocol and show that both methods produce comparable results for size determination of RNA molecules and subsequent Northern blotting of gels. In addition to purified RNA samples, the robustness of the TAE/formamide protocol is demonstrated by its suitability for the analysis of RNA quality in crude yeast cell lysates containing large amounts of proteins, DNA, and other contaminating molecules. We therefore propose the TAE/formamide agarose electrophoresis as a rapid, simple, and cheaper alternative to current methods of RNA electrophoresis. Additionally, another benefit is the reduced exposure of laboratory personnel to hazardous chemicals. 相似文献
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