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71.
Eight putative consistently expressed genes in Carnobacterium maltaromaticum and Lactobacillus curvatus, and nine in Listeria innocua, were examined for their potential as references for the normalization of gene expression. Expression stability of candidate reference genes was evaluated under growth conditions of low (5 °C) and moderately high (40–42.5 °C) temperatures, and high salt (≥3 % NaCl) using the geNormplus and NormFinder algorithms. Under temperature stress, both algorithms ranked elongation factor Tu (Tuf) as the most stably expressed gene in C. maltaromaticum. In L. curvatus, at similar conditions, geNormplus identified Tuf and 6-phosphogluconate dehydrogenase (6PGDH) as suitable for normalization, while NormFinder identified phenylalanyl-tRNA synthase and recombinase A as the best pair. In L. innocua grown under the same temperatures, geNormplus ranked 6PGDH, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and Tuf as the top three most stable references, whereas NormFinder identified GAPDH and 6PGDH as suitable for normalization, with Tuf ranked as number six. There was less consistency between algorithms in the salt stress experiment. No gene was identified that exhibited such a constant level of expression as to outperform the other candidates under both experimental conditions. This study underlines the need for normalizing bacterial gene expression using multiple carefully selected references. 相似文献
72.
Trond Kristiansen Charles Stock Kenneth F. Drinkwater Enrique N. Curchitser 《Global Change Biology》2014,20(5):1559-1584
Understanding the biophysical mechanisms that shape variability in fisheries recruitment is critical for estimating the effects of climate change on fisheries. In this study, we used an Earth System Model (ESM) and a mechanistic individual‐based model (IBM) for larval fish to analyze how climate change may impact the growth and survival of larval cod in the North Atlantic. We focused our analysis on five regions that span the current geographical range of cod and are known to contain important spawning populations. Under the SRES A2 (high emissions) scenario, the ESM‐projected surface ocean temperatures are expected to increase by >1 °C for 3 of the 5 regions, and stratification is expected to increase at all sites between 1950–1999 and 2050–2099. This enhanced stratification is projected to decrease large (>5 μm ESD) phytoplankton productivity and mesozooplankton biomass at all 5 sites. Higher temperatures are projected to increase larval metabolic costs, which combined with decreased food resources will reduce larval weight, increase the probability of larvae dying from starvation and increase larval exposure to visual and invertebrate predators at most sites. If current concentrations of piscivore and invertebrate predators are maintained, larval survival is projected to decrease at all five sites by 2050–2099. In contrast to past observed responses to climate variability in which warm anomalies led to better recruitment in cold‐water stocks, our simulations indicated that reduced prey availability under climate change may cause a reduction in larval survival despite higher temperatures in these regions. In the lower prey environment projected under climate change, higher metabolic costs due to higher temperatures outweigh the advantages of higher growth potential, leading to negative effects on northern cod stocks. Our results provide an important first large‐scale assessment of the impacts of climate change on larval cod in the North Atlantic. 相似文献
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75.
Pregnane X receptor-agonists down-regulate hepatic ATP-binding cassette transporter A1 and scavenger receptor class B type I 总被引:4,自引:0,他引:4
Sporstøl M Tapia G Malerød L Mousavi SA Berg T 《Biochemical and biophysical research communications》2005,331(4):1533-1541
Pregnane X receptor (PXR) is the molecular target for a wide variety of endogenous and xenobiotic compounds. It regulates the expression of genes central to the detoxification (cytochrome P-450 enzymes) and excretion (xenobiotic transporters) of potentially harmful compounds. The aim of the present investigation was to determine the role of PXR in regulation of high-density lipoprotein (HDL) cholesterol metabolism by studying its impact on ATP-binding cassette transporter A1 (ABCA1) and scavenger receptor class B type I (SR-BI) expression in hepatocytes. ABCA1 and SR-BI are major factors in the exchange of cholesterol between cells and HDL. Expression analyses were performed using Western blotting and quantitative real time RT-PCR. Luciferase reporter gene assays were used to measure promoter activities. Total cholesterol was measured enzymatically after lipid extraction (Folch's method). The expression of ABCA1 and SR-BI was inhibited by the PXR activators rifampicin and lithocholic acid (LCA) in HepG2 cells and pregnenolone 16alpha-carbonitrile (PCN) in primary rat hepatocytes. Thus, PXR appears to be a regulator of hepatic cholesterol transport by inhibiting genes central to cholesterol uptake (SR-BI) and efflux (ABCA1). 相似文献
76.
Ciocoiu CC Ravna AW Sylte I Rustan AC Hansen TV 《Bioorganic & medicinal chemistry》2011,19(23):6982-6988
(±)-2-Fluoro-2-(2-methyl-4-(((4-methyl-2-(4-(trifluoromethyl)phenyl)thiazol-5-yl)methyl)thio)phenoxy)acetic acid (2a) has been prepared and subjected to biological testing against all three subtypes of the PPARs. This compound exhibited agonist effects with EC(50) values of 560 and 55 nM against PPARα and PPARδ, respectively, in a luciferase assay. Moreover, compound (±)-2a also exhibited potent ability to induce oleic acid oxidation in a human myotube cell assay with EC(50)=3.7 nM. Compound (±)-2a can be classified as a dual PPARα/δ agonist with a 10-fold higher potency against the PPARδ receptor than against the PPARα receptor. Molecular modeling studies revealed that both enantiomers of 2a bind to the PPARδ receptor with similar binding energies. 相似文献
77.
Sebastian Patzke Sambra Redick Abdirashid Warsame Carlos A. Murga-Zamalloa Hemant Khanna Stephen Doxsey Trond Stokke 《Molecular biology of the cell》2010,21(15):2555-2567
We described previously the cell cycle- and microtubule-related functions of two splice isoforms of the centrosome spindle pole-associated protein (CSPP and CSPP-L). Here, we show that endogenous CSPP isoforms not only localize to centrosomes and the midbody in cycling cells but also extend to the cilia axoneme in postmitotic resting cells. They are required for ciliogenesis in hTERT-RPE1 cells in vitro and are expressed in ciliated renal, retinal, and respiratory cells in vivo. We report that CSPP isoforms require their common C-terminal domain to interact with Nephrocystin 8 (NPHP8/RPGRIP1L) and to form a ternary complex with NPHP8 and NPHP4. We find CSPP-L to be required for the efficient localization of NPHP8 but not NPHP4 to the basal body. The ciliogenesis defect in hTERT-RPE1 cells is, however, not mediated through loss of NPHP8. Similar to the effects of ectopical expression of CSPP-L, cilia length increased in NPHP8-depleted cells. Our results thus suggest that CSPP proteins may be involved in further cytoskeletal organization of the basal body and its primary cilium. To conclude, we have identified a novel, nonmitotic function of CSPP proteins placing them into a ciliary protein network crucial for normal renal and retinal tissue architecture and physiology. 相似文献
78.
There is lack of studies investigating the association between bodyweight changes and health related quality of life (HRQL). The aim was to study the effect of relative changes in bodyweight over time on HRQL. In the Hordaland Health Study, 9276 men and 10433 women aged 40–47 years were included. Weight and height were measured and information on bodyweight changes during the last 5 years, physical activity and smoking was obtained from self–administered questionnaires including the Medical Outcomes Study MOS short form-12 including a Physical health Composite Score (PCS) and a Mental health Composite Score (MCS). Increasing bodyweight changes were associated with marked reduced scores in PCS and MCS also after adjustment for body mass index (BMI), physical activity and smoking. Men and women with a variation in weight with more than 15% during the last 5 years reported a mean score of MCS that was 0.48 standard deviation (SD) (3.9/8.1) and 0.35 SD (3.1/8.9) lower than those reporting a variation in weight less than 5%. No major differences were found between those who at date of examination were at the lower and higher end of the reported weight interval. There were no significant differences in the associations between men and women. Our findings confirm that increasing bodyweight changes are associated with reduced physical and mental health beyond what is related to BMI itself. 相似文献
79.
Tomasz Maciej Stepniewski Mariona Torrens-Fontanals Ismael Rodríguez-Espigares Toni Giorgino Karoline G. Primdahl Anders Vik Yngve Stenstrøm Jana Selent Trond Vidar Hansen 《Bioorganic & medicinal chemistry》2018,26(12):3580-3587
The oxoeicosanoid receptor 1 (OXER1) is a member of the G-protein coupled receptors (GPCR) family, and is involved in inflammatory processes and oncogenesis. As such it is an attractive target for pharmacological intervention. The present study aimed to shed light on the molecular fundaments of OXER1 modulation using chemical probes structurally related to the natural agonist 5-oxo-ETE. In a first step, 5-oxo-ETE and its closely related derivatives (5-oxo-EPE and 4-oxo-DHA) were obtained by conducting concise and high-yielding syntheses. The biological activity of obtained compounds was assessed in terms of potency (EC50) and efficacy (Emax) for arrestin recruitment. Finally, molecular modelling and simulation were used to explore binding characteristics of 5-oxo-ETE and derivatives with the aim to rationalize biological activity. Our data suggest that the tested 5-oxo-ETE derivatives (i) insert quickly into the membrane, (ii) access the receptor via transmembrane helices (TMs) 5 and 6 from the membrane side and (iii) drive potency and efficacy by differential interaction with TM5 and 7. Most importantly, we found that the methyl ester of 5-oxo-ETE (1a) showed even a higher maximum response than the natural agonist (1). In contrast, shifting the 5-oxo group into position 4 results in inactive compounds (4-oxo DHA compounds (3) and (3a)). All in all, our study provides relevant structural data that help understanding better OXER1 functionality and its modulation. The structural information presented herein will be useful for designing new lead compounds with desired signalling profiles. 相似文献
80.
Helle M. Meltzer Håvard H. Mundal Jan Alexander Karen Bibow Trond A. Ydersbond 《Biological trace element research》1995,48(1):118-118
The online version of the original article can be found at 相似文献