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1.
Endogenous protein phosphorylation patterns were compared in occluded and non-occluded cytosol fractions prepared from rat forebrain. The occluded fraction was taken as representative of synaptosomal cytosol. One- and two-dimensional autoradiographs revealed the presence in non-occluded cytosol of a substrate for cAMP- and Ca2+/calmodulin-dependent protein kinase activities of Mr 300kD, corresponding to phosphorylated microtubule-associated protein-2 (MAP-2); this protein was absent in occluded cytosol. In contrast, a major substrate for protein kinase C was observed exclusively in occluded cytosol after phosphorylation under basal conditions. However, after phosphorylation in the presence of exogenous lipids, approximately equal amounts of the 82kD substrate were detected in both fractions, suggesting that protein kinase C in the occluded fraction was present in a partially activated state. Other minor differences in phosphorylation patterns between the two fractions were observed.Special Issue dedicated to Prof. Eduardo De Robertis. 相似文献
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G?k?e Güllü Irem Peker Aptullah Haholu Fatih Eren Zafer Kü?ükodaci Bülent Güle? Hüseyin Baloglu Can Erzik Ayse ?zer Mustafa Akkiprik 《Genetics and molecular biology》2015,38(1):21-29
The functional role of IGFBP5 in breast cancer is complicated. Experimental and
bioinformatics studies have shown that IGFBP5 is targeted by miR-140-5p and miR-193b,
although this has not yet been proven in clinical samples. The aim of this study was
to evaluate the expression of miR-140-5p and miR-193b in breast cancer and adjacent
normal tissue and assess its correlation with IGFBP5 and the clinicopathological
characteristics of the tumors. IGFBP5 protein expression was analyzed
immunohistochemically and IGFBP5, miR-140 and miR-193b mRNA expression levels were
analyzed with real-time RT-PCR. Tumor tissue had higher miR-140-5p expression than
adjacent normal tissue (p = 0.015). Samples with no immunohistochemical staining for
IGFBP5 showed increased miR-140-5p expression (p = 0.009). miR-140-5p expression was
elevated in invasive ductal carcinomas (p = 0.002), whereas basal-like tumors had
decreased expression of miR-140-5p compared to other tumors (p = 0.008). Lymph
node-positive samples showed an approximately 13-fold increase in miR-140-5p
expression compared to lymph node-negative tissue (p = 0.049). These findings suggest
that miR-140-5p, but not miR-193b, could be an important determinant of IGFBP5
expression and clinical phenotype in breast cancer patients. Further studies are
needed to clarify the expressional regulation of IGFBP5 by miR-140-5p. 相似文献
4.
Senol Sefika Pinar Temiz-Resitoglu Meryem Guden Demet Sinem Sari Ayse Nihal Sahan-Firat Seyhan Tunctan Bahar 《Neurochemical research》2021,46(3):624-637
Neurochemical Research - A selective RXR agonist, bexarotene, has been shown to have anti-inflammatory, anti-nociceptive, and neuroprotective effects in several models of numerous neurological... 相似文献
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The use of biological means for ground improvement have become popular, which generally works through the process called microbially-induced calcium carbonate precipitation (MICP). Many studies indicate successful application of MICP based improvement with multiple bacteria and on several soils. Given the proven performance of MICP, this study aims to examine the MICP process by comparing the calcium carbonate precipitation ability of widely studied bacteria, i.e., Sporosarcina pasteurii and relatively under-recognized bacteria, i.e., Bacillus licheniformis to outline the formation success. For this purpose, two different sands were tested for observing precipitation behavior using a series of syringe tests. Furthermore, the effect of concentration and inclusion of calcium chloride for nutrition of bacteria, saturation with water, and hybrid use of two bacteria were investigated in some tests for diversification. X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive x-ray spectroscopy (EDS) were used for the interpretation of results. Results indicated that Sporosarcina pasteurii had performed superior over Bacillus licheniformis when achieving calcium carbonate precipitation in tests for both sands. In addition, many intriguing SEM images contributed to the literature of MICP monitoring, highlighting the effects of the variables investigated. 相似文献
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Reconstructing a tree of life by inferring evolutionary history is an important focus of evolutionary biology. Phylogenetic reconstructions also provide useful information for a range of scientific disciplines such as botany, zoology, phylogeography, archaeology and biological anthropology. Until the development of protein and DNA sequencing techniques in the 1960s and 1970s, phylogenetic reconstructions were based on fossil records and comparative morphological/physiological analyses. Since then, progress in molecular phylogenetics has compensated for some of the shortcomings of phenotype-based comparisons. Comparisons at the molecular level increase the accuracy of phylogenetic inference because there is no environmental influence on DNA/peptide sequences and evaluation of sequence similarity is not subjective. While the number of morphological/physiological characters that are sufficiently conserved for phylogenetic inference is limited, molecular data provide a large number of datapoints and enable comparisons from diverse taxa. Over the last 20 years, developments in molecular phylogenetics have greatly contributed to our understanding of plant evolutionary relationships. Regions in the plant nuclear and organellar genomes that are optimal for phylogenetic inference have been determined and recent advances in DNA sequencing techniques have enabled comparisons at the whole genome level. Sequences from the nuclear and organellar genomes of thousands of plant species are readily available in public databases, enabling researchers without access to molecular biology tools to investigate phylogenetic relationships by sequence comparisons using the appropriate nucleotide substitution models and tree building algorithms. In the present review, the statistical models and algorithms used to reconstruct phylogenetic trees are introduced and advances in the exploration and utilization of plant genomes for molecular phylogenetic analyses are discussed. 相似文献
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Andrew D. James Waseema Patel Zohra Butt Magretta Adiamah Raga Dakhel Ayse Latif Carolina Uggenti Eileithyia Swanton Hiromi Imamura Ajith K. Siriwardena Jason I. E. Bruce 《The Journal of biological chemistry》2015,290(41):24760-24771
Evidence suggests that the plasma membrane Ca2+-ATPase (PMCA), which is critical for maintaining a low intracellular Ca2+ concentration ([Ca2+]i), utilizes glycolytically derived ATP in pancreatic ductal adenocarcinoma (PDAC) and that inhibition of glycolysis in PDAC cell lines results in ATP depletion, PMCA inhibition, and an irreversible [Ca2+]i overload. We explored whether this is a specific weakness of highly glycolytic PDAC by shifting PDAC cell (MIA PaCa-2 and PANC-1) metabolism from a highly glycolytic phenotype toward mitochondrial metabolism and assessing the effects of mitochondrial versus glycolytic inhibitors on ATP depletion, PMCA inhibition, and [Ca2+]i overload. The highly glycolytic phenotype of these cells was first reversed by depriving MIA PaCa-2 and PANC-1 cells of glucose and supplementing with α-ketoisocaproate or galactose. These culture conditions resulted in a significant decrease in both glycolytic flux and proliferation rate, and conferred resistance to ATP depletion by glycolytic inhibition while sensitizing cells to mitochondrial inhibition. Moreover, in direct contrast to cells exhibiting a high glycolytic rate, glycolytic inhibition had no effect on PMCA activity and resting [Ca2+]i in α-ketoisocaproate- and galactose-cultured cells, suggesting that the glycolytic dependence of the PMCA is a specific vulnerability of PDAC cells exhibiting the Warburg phenotype. 相似文献
8.
Erdogan Kocamaz Duygu Gok Ayse Cetinkaya A. Cevik Tufan 《Journal of molecular histology》2012,43(5):497-508
This study investigated the involvement of CNP-3, chick homologue for human C-type natriuretic peptide (CNP), in TGF-β1 induced chondrogenic differentiation of chicken bone marrow-derived mesenchymal stem cells (MSCs). Chondrogenic differentiation of MSCs in pellet cultures was induced by TGF-β1. Chondrogenic differentiation and glycosaminoglycan synthesis were analyzed on the basis of basic histology, collagen type II expression, and Alcian blue staining. Antibodies against CNP and NPR-B were used to block their function during these processes. Results revealed that expression of CNP-3 and NPR-B in MSCs were regulated by TGF-β1 in monolayer cultures at mRNA level. In pellet cultures of MSCs, TGF-β1 successfully induced chondrogenic differentiation and glycosaminoglycan synthesis. Addition of CNP into the TGF-β1 supplemented chondrogenic differentiation medium further induced the glycosaminoglycan synthesis and hypertrophy of differentiated chondrocytes in these pellets. Pellets induced with TGF-β1 and treated with antibodies against CNP and NPR-B, did show collagen type II expression, however, Alcian blue staining showing glycosaminoglycan synthesis was significantly suppressed. In conclusion, CNP-3/NPR-B signaling may strongly be involved in synthesis of glycosaminoglycans of the chondrogenic matrix and hypertrophy of differentiated chondrocytes during TGF-β1 induced chondrogenic differentiation of MSCs. 相似文献
9.
Blanca Arango-Gonzalez Dragana Trifunovi? Ayse Sahaboglu Katharina Kranz Stylianos Michalakis Pietro Farinelli Susanne Koch Fred Koch Sandra Cottet Ulrike Janssen-Bienhold Karin Dedek Martin Biel Eberhart Zrenner Thomas Euler Per Ekstr?m Marius Ueffing Fran?ois Paquet-Durand 《PloS one》2014,9(11)
Cell death in neurodegenerative diseases is often thought to be governed by apoptosis; however, an increasing body of evidence suggests the involvement of alternative cell death mechanisms in neuronal degeneration. We studied retinal neurodegeneration using 10 different animal models, covering all major groups of hereditary human blindness (rd1, rd2, rd10, Cngb1 KO, Rho KO, S334ter, P23H, Cnga3 KO, cpfl1, Rpe65 KO), by investigating metabolic processes relevant for different forms of cell death. We show that apoptosis plays only a minor role in the inherited forms of retinal neurodegeneration studied, where instead, a non-apoptotic degenerative mechanism common to all mutants is of major importance. Hallmark features of this pathway are activation of histone deacetylase, poly-ADP-ribose-polymerase, and calpain, as well as accumulation of cyclic guanosine monophosphate and poly-ADP-ribose. Our work thus demonstrates the prevalence of alternative cell death mechanisms in inherited retinal degeneration and provides a rational basis for the design of mutation-independent treatments. 相似文献
10.
Dielectric heaters and sealers present the most common source of occupational exposure to excessive radio frequency (RF) fields. These systems are used industrially to heat or melt dielectric materials. Nowadays, the effects of high frequency electromagnetic (EM) fields on the health have been discussed frequently but there are few health studies done for workers around dielectric heaters and sealers. In this study, the leakage fields around dielectric heaters and sealers (27.12?MHz) were measured in MKE--Mechanical and Chemical Industry Corporation, Gazi Rocket Factory and evaluated in terms of standards. It has been observed that operators exposed to same RF fields with occupational exposure limits. Many workers have health complaints, such as elevated body temperatures in the factory. Safe distances or areas for workers should be recommended in these systems. Protective measures could be implemented to minimize these exposures. Further measurements and occupational exposure studies of RF exposed women and men are needed to demonstrate the levels of exposed Radio Frequency Radiation (RFR). Precautions should therefore be taken either to reduce the leakage fields or minimise the exposed fields. 相似文献