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61.
62.
Sergej Tomi? Jelena ?oki? Sa?a Vasiliji? Nina Ogrinc Rebeka Rudolf Primo? Pelicon Dragana Vu?evi? Petar Milosavljevi? Sr?a Jankovi? Ivan An?el Jelena Rajkovi? Marjan Slak Rupnik Bernd Friedrich Miodrag ?oli? 《PloS one》2014,9(5)
Gold nanoparticles (GNPs) are claimed as outstanding biomedical tools for cancer diagnostics and photo-thermal therapy, but without enough evidence on their potentially adverse immunological effects. Using a model of human dendritic cells (DCs), we showed that 10 nm- and 50 nm-sized GNPs (GNP10 and GNP50, respectively) were internalized predominantly via dynamin-dependent mechanisms, and they both impaired LPS-induced maturation and allostimulatory capacity of DCs, although the effect of GNP10 was more prominent. However, GNP10 inhibited LPS-induced production of IL-12p70 by DCs, and potentiated their Th2 polarization capacity, while GNP50 promoted Th17 polarization. Such effects of GNP10 correlated with a stronger inhibition of LPS-induced changes in Ca2+ oscillations, their higher number per DC, and more frequent extra-endosomal localization, as judged by live-cell imaging, proton, and electron microscopy, respectively. Even when released from heat-killed necrotic HEp-2 cells, GNP10 inhibited the necrotic tumor cell-induced maturation and functions of DCs, potentiated their Th2/Th17 polarization capacity, and thus, impaired the DCs'' capacity to induce T cell-mediated anti-tumor cytotoxicity in vitro. Therefore, GNP10 could potentially induce more adverse DC-mediated immunological effects, compared to GNP50. 相似文献
63.
Since their discovery, fermentation processes have gone along not only with the industrial beverages production and breweries, but since the times of Alexander Fleming, they have become a crucial part of the health care due to antibiotics production. However, complicated dynamics and strong nonlinearities cause that the production with the use of linear control methods achieves only suboptimal yields. From the variety of nonlinear approaches, gradient method has proved the ability to handle these issues—nevertheless, its potential in the field of fermentation processes has not been revealed completely. This paper describes constant vaporization control strategy based on a double-input optimization approach with a successful reduction to a single-input optimization task. To accomplish this, model structure used in the previous work is modified so that it corresponds with the new optimization strategy. Furthermore, choice of search step is explored and various alternatives are evaluated and compared. 相似文献
64.
Dariga U. Akasheva Ekaterina V. Plokhova Olga N. Tkacheva Irina D. Strazhesko Ekaterina N. Dudinskaya Anna S. Kruglikova Valentina S. Pykhtina Natalia V. Brailova Inna A. Pokshubina Natalia V. Sharashkina Mikhail V. Agaltsov Dmitry Skvortsov Sergey A. Boytsov 《PloS one》2015,10(8)
Introduction
With advancing age the left ventricle (LV) undergoes structural and functional changes, thereby creating the substrate for the development of diseases. One possible mechanism of the ageing heart is a cellular senescence. Leukocyte telomere length (LTL) is a marker of replicative ageing. The purpose of this study was to evaluate the structure and function of the LV in people of different ages free of cardiovascular diseases (CVD) and regular drug medication and to assess their relationship with LTL. We hypothesized that age-related changes in LV myocardium are associated with telomere length.Methods
The study population consisted of 150 healthy, non-obese volunteers aged 28 to 78 years without history of CVD, significant deviations by 12-lead electrocardiogram and negative exercise test (treadmill stress test). All the participants underwent standardized transthoracic echocardiography using an available system (iE33; Philips). The LTL was measured by real-time quantitative polymerase chain reaction. We determined the relative ratio of telomere repeat copy number (T) to single-copy gene copy number (S).Results
In the older people there was a higher wall thickness than in the younger (1.03±0.09 vs. 0.88±0.10, p<0.01), whereas LV mass index was comparable between them (85.8±15.40 vs. 83.1±11.8, p = 0.20). There was a decrease in LV dimensions with advancing age (p<0.001). Older subjects had impairment in LV relaxation. LTL was associated with decreased E/A, Em/Am ratio (β = -0.323, p = 0.0001) after adjusting for age, sex and risk factors. There is no relation between the LTL and the structure of LV.Conclusions
Our data suggest that the ageing process leads to changes in LV structure and diastolic function and is linked with a phenotype of concentric LV remodeling. Telomere attrition is associated with age-related LV diastolic dysfunction. Telomere length appears to be a biomarker of myocardial ageing. 相似文献65.
Anastasija Zaiko Maiju Lehtiniemi Aleksas Narščius Sergej Olenin 《Biological invasions》2011,13(8):1739-1765
This paper presents an overall bioinvasion impact assessment on the scale of a large marine region—the Baltic Sea, as defined
by the Helsinki Commission. The methodology is based on a classification of the abundance and distribution range of alien
species and the magnitude of their impacts on native communities, habitats and ecosystem functioning aggregated in a “Biopollution
Level” index (BPL) which ranges from ‘no impact’ (BPL = 0) to ‘massive impact’ (BPL = 4). The assessment performed for nine
Baltic sub-regions revealed that documented ecological impact is only known for 43 alien species out of 119 registered in
the Sea. The highest biopollution (BPL = 3, strong impact) occurs in coastal lagoons, inlets and gulfs, and the moderate biopollution
(BPL = 2)—in the open sea areas. The methodology was also used to classify species into alien (BPL = 0) versus ‘impacting’
species (BPL > 0), which can be divided into ‘potentially invasive’ (BPL = 1) and ‘invasive’ (BPL > 1) ones. No clear correlation
between the number of established alien and impacting species was found in the sub-regions of the Baltic Sea. The methodology,
although requiring a substantial research effort, proved to be useful for interregional comparisons and evaluating the bioinvasion
effects of individual alien species. 相似文献
66.
Sergej Nadalin Jasminka Giacometti Suzana Jonovska Draško Tomljanović Alena Buretić-Tomljanović 《Prostaglandins, leukotrienes, and essential fatty acids》2013,88(2):185-190
We investigated the etiology of the attenuated niacin skin flush response in schizophrenia patients. Skin response to topical niacin of 0.1 M, 0.01 M, 0.001 M, and 0.0001 M concentrations was rated using method of volumetric niacin response (VNR) and correlated to two functional A/G polymorphisms in genes: phospholipase A2 group IVA (BanI of the PLA2G4A), and rs689466 of the prostaglandin synthase-2 (PTGS2). We further tested the possible correlation between niacin response and fatty acid (FA) content of red blood cells (RBCs). We detected statistically significant but weak impact of both polymorphisms on niacin flush response in schizophrenia patients. The dosage of the G alleles of both polymorphisms was associated with higher VNR values, although each polymorphic variant accounted for only 1% of the overall flush response variability. Regarding FA content, both n?3 and n?6 polyunsaturated FAs (PUFAs) were significantly reduced in the patient group, but an association with niacin sensitivity was not detected. 相似文献
67.
Schmidt O Schuenemann VJ Hand NJ Silhavy TJ Martin J Lupas AN Djuranovic S 《Journal of molecular biology》2007,372(4):894-905
68.
Konopliannikov AG Proskuriakov SIa Konopliannikov OA Trishkina AI Shteĭn LV Verkhovskiĭ IuG Kolesnikova AI Trofimova TP Mandrugin AA Fedoseev VM Bachurin SO Proshin AN Skvortsov VG 《Radiatsionnaia biologiia, radioecologiia / Rossi?skaia akademiia nauk》2007,47(1):5-9
In this work the attempt to estimate a nitric oxide (NO*) role in regulation of the number of pool haemopoietic stem cells at the irradiated mice was made. With this purpose the number of new compounds from dihydrothiazine-thiazoline line was synthesized, their NO-inhibiting activity was investigated in vivo by the method of ESR-spectroscopy of spin trap and their influence on an output endogenous spleen colonies (CFU-S-8) after the total sublethal y-irradiation of mice in a doze of 6 Gy was also investigated. Was shown, that the tested compounds reduced the contents of NO* in a liver tissue of mice which have received an injection of nitric oxide synthesis inductor - lipopolysaccharide, and also increased an output CFU-S-8 forming endogenous colonies in the spleen of the irradiated mice. Received data testify to perceptivity of search radioprotective agents among NO* synthesis inhibitors. 相似文献
69.
Schwörer Christoph Gobet Erika van Leeuwen Jacqueline F. N. Bögli Sarah Imboden Rachel van der Knaap W. O. Kotova Nadezhda Makhortykh Sergej Tinner Willy 《Vegetation History and Archaeobotany》2022,31(2):155-170
Vegetation History and Archaeobotany - Observing natural vegetation dynamics over the entire Holocene is difficult in Central Europe, due to pervasive and increasing human disturbance since the... 相似文献
70.
Romana Šínová Jana Kudová Kristina Nešporová Sergej Karel Romana Šuláková Vladimír Velebný Lukáš Kubala 《Journal of cellular physiology》2019,234(8):13209-13219
The stimulation of myocardium repair is restricted due to the limited understanding of heart regeneration. Interestingly, endogenous opioid peptides such as dynorphins and enkephalins are suggested to support this process. However, the mechanism—whether through the stimulation of the regenerative capacity of cardiac stem cells or through effects on other cell types in the heart—is still not completely understood. Thus, a model of the spontaneous cardiomyogenic differentiation of mouse embryonic stem (mES) cells via the formation of embryoid bodies was used to describe changes in the expression and localization of opioid receptors within cells during the differentiation process and the potential of the selected opioid peptides, dynorphin A and B, and methionin-enkephalins and leucin-enkephalins, to modulate cardiomyogenic differentiation in vitro. The expressions of both κ- and δ-opioid receptors significantly increased during mES cell differentiation. Moreover, their primary colocalization with the nucleus was followed by their growing presence on the cytoplasmic membrane with increasing mES cell differentiation status. Interestingly, dynorphin B enhanced the downregulation gene expression of Oct4 characteristic of the pluripotent phenotype. Further, dynorphin B also increased cardiomyocyte-specific Nkx2.5 gene expression. However, neither dynorphin A nor methionin-enkephalins and leucin-enkephalins exhibited any significant effects on the course of mES cell differentiation. In conclusion, despite the increased expression of opioid receptors and some enhancement of mES cell differentiation by dynorphin B, the overall data do not support the notion that opioid peptides have a significant potential to promote the spontaneous cardiomyogenesis of mES cells in vitro. 相似文献