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171.
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Peter Kubatka Martin Kello Karol Kajo Marek Samec Alena Liskova Karin Jasek Lenka Koklesova Tomas Kuruc Marian Adamkov Karel Smejkal Emil Svajdlenka Peter Solar Martin Pec Dietrich Büsselberg Vladimira Sadlonova Jan Mojzis 《International journal of molecular sciences》2021,22(1)
Comprehensive scientific data provide evidence that isolated phytochemicals or whole plant foods may beneficially modify carcinogenesis. The aim of this study was to evaluate the oncostatic activities of Rhus coriaria L. (sumac) using animal models (rat and mouse), and cell lines of breast carcinoma. R. coriaria (as a powder) was administered through the diet at two concentrations (low dose: 0.1% (w/w) and high dose: 1 % (w/w)) for the duration of the experiment in a syngeneic 4T1 mouse and chemically-induced rat mammary carcinoma models. After autopsy, histopathological and molecular analyses of tumor samples in rodents were performed. Moreover, in vitro analyses using MCF-7 and MDA-MB-231 cells were conducted. The dominant metabolites present in tested R. coriaria methanolic extract were glycosides of gallic acid (possible gallotannins). In the mouse model, R. coriaria at a higher dose (1%) significantly decreased tumor volume by 27% when compared to controls. In addition, treated tumors showed significant dose-dependent decrease in mitotic activity index by 36.5% and 51% in comparison with the control group. In the chemoprevention study using rats, R. coriaria at a higher dose significantly reduced the tumor incidence by 20% and in lower dose non-significantly reduced tumor frequency by 29% when compared to controls. Evaluations of the mechanism of oncostatic action using valid clinical markers demonstrated several positive alterations in rat tumor cells after the treatment with R. coriaria. In this regard, histopathological analysis of treated tumor specimens showed robust dose-dependent decrease in the ratio of high-/low-grade carcinomas by 66% and 73% compared to controls. In treated rat carcinomas, we found significant caspase-3, Bax, and Bax/Bcl-2 expression increases; on the other side, a significant down-regulation of Bcl-2, Ki67, CD24, ALDH1, and EpCam expressions and MDA levels. When compared to control specimens, evaluation of epigenetic alterations in rat tumor cells in vivo showed significant dose-dependent decrease in lysine methylation status of H3K4m3 and H3K9m3 and dose-dependent increase in lysine acetylation in H4K16ac levels (H4K20m3 was not changed) in treated groups. However, only in lower dose of sumac were significant decreases in the expression of oncogenic miR210 and increase of tumor-suppressive miR145 (miR21, miR22, and miR155 were not changed) observed. Finally, only in lower sumac dose, significant decreases in methylation status of three out of five gene promoters–ATM, PTEN, and TIMP3 (PITX2 and RASSF1 promoters were not changed). In vitro evaluations using methanolic extract of R. coriaria showed significant anticancer efficacy in MCF-7 and MDA-MB-231 cells (using Resazurin, cell cycle, annexin V/PI, caspase-3/7, Bcl-2, PARP, and mitochondrial membrane potential analyses). In conclusion, sumac demonstrated significant oncostatic activities in rodent models of breast carcinoma that were validated by mechanistic studies in vivo and in vitro. 相似文献
173.
Karin G. M. Lenssen Aalt Bast Alie de Boer 《Comprehensive Reviews in Food Science and Food Safety》2019,18(4):910-922
The efficacy of botanicals in medicines can be substantiated with evidence on traditional use, whereas in foodstuffs, this is often not possible. In Europe, for example, the evaluation and subsequent authorization of health claims on herbal dietary supplements (HDS) have been put on hold by the European Commission. This study aims to analyze the role of evidence on traditional use in international legal frameworks of foods and pharmaceuticals. Both legal sources as well as scientific studies offering insights into these regulatory frameworks were included into the analysis. The international approach toward evidence on traditional use for substantiating efficacy of botanicals varies highly. For herbal medicines, substantiating efficacy with evidence on traditional use is possible in all studied jurisdictions, except for Japan and the United States. HDS efficacy can only be substantiated with evidence on traditional use in India and New Zealand, although the enforcing authorities do not describe which data are required. Australia and Canada regulate botanicals in a separate “borderline” category from foods and pharmaceuticals. Both jurisdictions allow for substantiating efficacy with evidence on traditional use. This study's second objective was to assess the applicability of the international approaches in the European legal framework, in light of the ongoing political debate regarding the use of traditional evidence. Implementation of the analyzed international approaches would require major revisions of the current European legal framework. This review of international approaches might, however, aid in deciding upon future approaches for substantiating health claims with evidence on traditional use. 相似文献
174.
175.
Knowledge‐Based Conceptual Synthesis of Industrial‐Scale Downstream Processes for Biochemical Products 下载免费PDF全文
Karin Backhaus Mirka Lochmüller Markus Christian Arndt Ole Riechert Gerhard Schembecker 《化学工程与技术》2015,38(3):537-546
A generic, knowledge‐based guideline assisting downstream process synthesis for biochemical products is presented. It offers process designers a structured process design methodology supporting them in capturing potentially relevant information, which might be beyond their expertise. The guideline is based on heuristic knowledge which was collected, structured in a generic way, and clearly represented. The generation of alternative downstream routes as starting points for experiments, simulation, and cost calculation is hereby accelerated. The application of the guideline is demonstrated on the example of penicillin V downstream processing from fermentation broth. 相似文献
176.
Cor a 14, the allergenic 2S albumin from hazelnut,is highly thermostable and resistant to gastrointestinal digestion 下载免费PDF全文
177.
The adaptations of the mouse uterus to pregnancy include extensive modifications of the cells and extracellular matrix of the endometrial connective tissue that surround the embryos. Around each implanted embryo this tissue redifferentiates into a transient structure called decidua, which is formed by polygonal cells joined by intercellular junctions. In the mouse, thick collagen fibrils with irregular profile appear in decidualized areas of the endometrium but not in the nondecidualized stroma and interimplantation sites. The fine organization of these thick fibrils has not yet been established. This work was addressed to understand the arrangement and fine structure of collagen fibrils of the decidua of pregnant mice during the periimplantation stage. Major modifications occurred in collagen fibrils that surrounded decidual cells: (1) the fibrils, which were arranged in parallel bundles in nonpregnant animals, became organized as baskets around decidual cells; (2) very thick collagen fibrils with very irregular profiles appeared around decidual cells. Analysis of replicas and serial sections suggests that the thick collagen fibrils form by the lateral aggregation of thinner fibrils to a central fibril resulting in very irregular profile observed in cross sections of thick fibrils. The sum of modifications of the collagen fibrils seem to represent an adaptation of the endometrium to better support the decidual cells while they hold the embryos during the beginning of their development. The deposition of thick collagen fibrils in the decidua may contribute to form a barrier that impedes leukocyte migration within the decidua, preventing immunological rejection of genetically dissimilar embryonic tissues. 相似文献
178.
Gwen V. Childs Karin N. Westlund Robert E. Tibolt Jonathan M. Lloyd 《Microscopy research and technique》1991,19(1):21-41
Hypothalamic regulatory peptides bind to specific receptors on target cells in the pituitary and control secretion. They in turn can be regulated at the pituitary level by steroid and peptide modulators. Affinity cytochemical techniques are important tools for the identification of specific target binding sites for these regulatory peptides. This presentation reviews the work in which potent, biotinylated ligands of gonadotropin releasing hormone (bio-GnRH), corticotropin releasing hormone (bio-CRH), and arginine vasopressin (bio-AVP) were applied to study the target cell responses. Bio-GnRH, bio-CRH, and bio-AVP bind to membrane receptors on specific anterior pituitary cells. Dual labeling for either gonadotropin or adrenocorticotropin (ACTH) antigens further identified the target cells. After 1–3 minutes, the label was in patches or capped on the surface. After 3 minutes, it was internalized in small vesicles and sent to receptosomes and vacuoles in the Golgi complex. Eventually the biotinylated peptides, or a metabolite, was found in the lysosomes (multivesicular bodies) and a subpopulation of secretory granules. The route and rate of uptake was similar to that described for the classical receptor-mediated endocytosis process. In contrast, intermediate lobe corticotropes internalized the bio-CRH in less than 1 minute. The route through the Golgi complex appeared to be bypassed. Instead the labeled peptide was in vesicles, on the membranes of scattered vacuoles, and in multivesicular bodies. Modulation of ligand binding by steroids showed that changes in receptor numbers correlated with changes in the number of cells that bound the ligand. In male rats, dihydrotestosterone reduced the percentage of GnRH-bound cells by 50%. Most of the reduction appeared in cells that stored luteinizing hormone (LH) antigens. In diestrous female rats, estradiol increased the percentage of bio-GnRH-bound cells. However, the steroid decreased the percentage of GnRH-bound cells in cells from proestrous rats. Glucocorticoids decreased the percentage of CRH-bound corticotropes in as little as 10 minutes. Potentiation of secretion by these ligands was correlated with increases in the percentage of ligand-bound cells. AVP pretreatment of corticotropes increased the percentage of cells that bound bio-CRH. It also increased the rate of receptor-mediated endocytosis of CRH and changed the route so that the Golgi complex was bypassed. This effect could be mimicked by activation of its second messengers (calcium and protein kinase C). Similarly, CRH pretreatment increased the percentage of corticotropes that bound AVP. Thyrotropin releasing hormone (TRH) pretreatment also increased the percentage of thyrotropes that bound AVP. Finally, calcium or sodium channel blockers altered CRH binding so that fewer cells were labeled. This binding by CRH was not dependent on extracellular calcium and tests with a calcium channel agonist showed that it was related to activation of calcium channels. To summarize, these affinity cytochemical studies have identified specific target cells in the pituitary for GnRH, CRH, and AVP. They have also identified heterogeneity in the population. They have demonstrated new information about the direct modulatory effects of steroids, ion channels, and neuropeptides on neuropeptide binding by subpopulations of these target cells. 相似文献
179.
Weida D. Chen A. Xavier Kohll Bichlien H. Nguyen Julian Koch Reinhard Heckel Wendelin J. Stark Luis Ceze Karin Strauss Robert N. Grass 《Advanced functional materials》2019,29(28)
In this paper the practical density of long‐term DNA storage is increased. Specifically, the DNA weight loading of silica sphere DNA storage is increased to 3.4 wt%, a ten‐fold increase compared to the previous state‐of‐the‐art. By applying a Layer‐by‐Layer (LbL) design with alternating layers of DNA and a polycationic molecule, namely polyethyleneimine (PEI), another dimension to DNA surface binding onto magnetic nanoparticles is added. A protective silica layer is grown on top of the multilayered nanoparticles to shield the DNA from external sources of damage. Accelerated aging experiments of the nanoparticles and the subsequent quantification of DNA stability via qPCR show a significantly lower degradation rate compared to unprotected DNA. The novel material is compared to previous DNA storage technologies, outperforming those in DNA storage density as well as stability. Finally, the storage of an 83 kB digital file in DNA through a successful readout of a 4991 oligonucleotide pool is demonstrated from particle encapsulation, through accelerated aging, to sequencing. 相似文献
180.