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991.
Considering the fact that some trace elements have influence on the growth and physiological processes in the fungi, the aim
of this study was to resolve the question of whether Fe, Zn, and Se, added to the medium in the different forms, affect activity
of selected Pleurotus eryngii ligninolytic enzymes participating in mandarine peels submerged fermentation. Compared with the control, Fe and Zn showed
stimulatory effect on laccase activity. Reduction in the activity was emphasized with cultivation time, but it was slower
in the presence of Zn than in the presence of Fe. Among studied Se forms, SeO2 was the most unfavorable Se source for laccase activity. All tested trace elements, independent on form, showed stimulatory
effect on the activity of Mn-oxidizing peroxidases on the seventh day of cultivation. Based on the results, it could be concluded
that the presence of the tested trace elements can advance various biotechnological processes among which is biodegradation
of agricultural wastes, potential environmental pollutants. 相似文献
992.
J. Dulčić A. Pallaoro S. Matić‐Skoko B. Dragičević P. Tutman R. Grgičević N. Stagličić V. Bukvić J. Pavličević B. Glamuzina M. Kraljević 《Zeitschrift fur angewandte Ichthyologie》2011,27(5):1254-1258
Age, growth and mortality were analysed for the common two‐banded seabream, Diplodus vulgaris, collected in the eastern Adriatic (Croatian coast) from commercial fishery catches by ‘tramata’ fishing (2005–2006) to obtain growth estimation. The oldest female was estimated to be age 11, the oldest male age 10 years. The von Bertalanffy growth parameters estimated by reading scales were: L∞ = 48.60 cm (SE = 1.101), K = 0.112 (SE = 0.005) and t0 = ?2.366 (SE = 0.060) for all specimens; L∞ = 51.96 cm (SE = 2.153), K = 0.095 (SE = 0.007) and t0 = ?2.837 (SE = 0.120) for females and L∞ = 56.25 cm (SE = 2.662), K = 0.084 (SE = 0.067) and t0 = ?2.920 (SE = 0.117) for males. The overall sex ratio was 1.22 : 1 in favour of males. Total mortality, corresponding to the slope of the descending limb of the catch curve, was Z = 0.81 per year for females and Z = 0.85 per year for males. Exploitation ratios were E = 0.68 for females and E = 0.73 for males. 相似文献
993.
994.
Neuropeptide Y (NPY) has been reported to be a potent anti-inflammatory peptide with ability to directly modulate activity of granulocytes and macrophages. The present study aimed to correlate the effects of NPY in vivo on lipopolysaccharide-induced air-pouch exudates cells and in vitro on peripheral blood leukocytes functions. The role of different Y receptors was examined using NPY-related peptides and antagonists with diverse subtype specificity and selectivity for Y receptors. Y1, Y2 and Y5 receptors were detected on air-pouch exudates cells (flow cytometry) and peripheral blood granulocytes (immunocitochemistry). NPY in vivo reduced inflammatory cells accumulation into the air pouch, and decreased their adherence and phagocytic capacity via Y2/Y5 and Y1/Y2 receptors, respectively. Quite the opposite, NPY in vitro potentiated adhesiveness and phagocytosis of peripheral blood granulocytes and monocytes by activating Y1 receptor. The differences between in vivo and in vitro effects of NPY on rat inflammatory cells functions are mostly due to dipeptidyl peptidase 4 activity. In addition, suppressive effect of NPY in vivo is highly dependent on the local microenvironment, peptide truncation and specific Y receptors interplay. 相似文献
995.
Milošević VLj Ajdžanović VZ Bogojević DB Medigović IM Ivanović-Matić SK Martinović VI Grigorov II 《General physiology and biophysics》2011,30(3):321-324
In peripubertal female rats, we have previously found that 50% food restriction (FR) increases plasma IL-6, haptoglobin and both alanine transaminase (ALT) and alkaline phosphatase (AST) aminotransferases, indicating the existence of an inflammatory response. To study whether such FR influences the hypothalamic-pituitary-adrenal (HPA) axis, we examined by immunohistochemistry the morphofunctional features of pituitary adrenocorticotroppic (ACTH) cells. In FR rats the volume and volume density of ACTH cells as well as plasma ACTH levels were increased by 17.6%, 12.5% and 13.4%, respectively, in comparison with controls (p<0.05). We concluded that chronic FR is a systemic stressor in young females, capable to stimulate the HPA axis, probably as a result of IL-6 action. 相似文献
996.
Kozłowski M Naumnik W Nikliński J Milewski R Lapuć G Laudański J 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》2011,49(1):90-97
The discovery of markers to lymphatic endothelial cells and the development of novel antibodies to these markers have brought increasing attention to the lymphatics and progress in the understanding of lymphangiogenesis and cancer metastasis. In this study, we investigate the presence of lymphatic vessel invasion (LVI) detected by D2-40 immunohistochemical staining in resected esophageal cancer and correlated with clinicopathologic data and patient survival. Sixty nine patients, who had a primary resection of esophageal cancer, were analyzed by univariate and multivariate logistic regression, and univariate and multivariate survival analysis. The total rate of LVI was 72% (50/69). Positive LVI was significantly correlated with lymph node metastasis (p < 0.001), tumor size (p < 0.001), histological grading (p = 0.017), tumor depth (p = 0.001), and stage (p < 0.001). Multivariate logistic analysis identified LVI (p = 0.036) as a predictor of regional lymph node metastasis. On univariate survival analysis, patients with LVI had a significantly shorter disease-free survival, cancer-specific survival and overall survival. Multivariate analysis proved that LVI diagnosed by D2-40 is an independent prognostic factor of both disease-free survival (p = 0.04) and overall survival (p = 0.032) in resected esophageal cancer. These results show that LVI assessment identifies patients at high risk for regional lymph node metastasis and that LVI is an independent prognostic factor in patients with esophageal cancer. 相似文献
997.
998.
Metalloprotease meprin beta generates nontoxic N-terminal amyloid precursor protein fragments in vivo 总被引:1,自引:0,他引:1
Jefferson T Čaušević M auf dem Keller U Schilling O Isbert S Geyer R Maier W Tschickardt S Jumpertz T Weggen S Bond JS Overall CM Pietrzik CU Becker-Pauly C 《The Journal of biological chemistry》2011,286(31):27741-27750
Identification of physiologically relevant substrates is still the most challenging part in protease research for understanding the biological activity of these enzymes. The zinc-dependent metalloprotease meprin β is known to be expressed in many tissues with functions in health and disease. Here, we demonstrate unique interactions between meprin β and the amyloid precursor protein (APP). Although APP is intensively studied as a ubiquitously expressed cell surface protein, which is involved in Alzheimer disease, its precise physiological role and relevance remain elusive. Based on a novel proteomics technique termed terminal amine isotopic labeling of substrates (TAILS), APP was identified as a substrate for meprin β. Processing of APP by meprin β was subsequently validated using in vitro and in vivo approaches. N-terminal APP fragments of about 11 and 20 kDa were found in human and mouse brain lysates but not in meprin β(-/-) mouse brain lysates. Although these APP fragments were in the range of those responsible for caspase-induced neurodegeneration, we did not detect cytotoxicity to primary neurons treated by these fragments. Our data demonstrate that meprin β is a physiologically relevant enzyme in APP processing. 相似文献
999.
1000.
Soderquest K Walzer T Zafirova B Klavinskis LS Polić B Vivier E Lord GM Martín-Fontecha A 《Journal of immunology (Baltimore, Md. : 1950)》2011,186(6):3304-3308
It is uncertain whether NK cells modulate T cell memory differentiation. By using a genetic model that allows the selective depletion of NK cells, we show in this study that NK cells shape CD8(+) T cell fate by killing recently activated CD8(+) T cells in an NKG2D- and perforin-dependent manner. In the absence of NK cells, the differentiation of CD8(+) T cells is strongly biased toward a central memory T cell phenotype. Although, on a per-cell basis, memory CD8(+) T cells generated in the presence or the absence of NK cells have similar functional features and recall capabilities, NK cell deletion resulted in a significantly higher number of memory Ag-specific CD8(+) T cells, leading to more effective control of tumors carrying model Ags. The enhanced memory responses induced by the transient deletion of NK cells may provide a rational basis for the design of new vaccination strategies. 相似文献