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41.
42.
Jing Zou Rohit Sood Sanjeev Ranjan Dennis Poe Usama A Ramadan Paavo KJ Kinnunen Ilmari Pyykkö 《Journal of nanobiotechnology》2010,8(1):32
Background
Treatment of inner ear diseases remains a problem because of limited passage through the blood-inner ear barriers and lack of control with the delivery of treatment agents by intravenous or oral administration. As a minimally-invasive approach, intratympanic delivery of multifunctional nanoparticles (MFNPs) carrying genes or drugs to the inner ear is a future therapy for treating inner ear diseases, including sensorineural hearing loss (SNHL) and Meniere's disease. In an attempt to track the dynamics and distribution of nanoparticles in vivo, here we describe manufacturing MRI traceable liposome nanoparticles by encapsulating gadolinium-tetra-azacyclo-dodecane-tetra-acetic acid (Gd-DOTA) (abbreviated as LPS+Gd-DOTA) and their distribution in the inner ear after either intratympanic or intracochlear administration. 相似文献43.
We quantified the effects of initial macroalgal tissue nitrogen (N) status (depleted and enriched) and varying pulses of nitrate (NO3?) concentration on uptake and storage of nitrogen in Ulva intestinalis L. and Ulva expansa (Setch.) Setch. et N. L. Gardner using mesocosms modeling shallow coastal estuaries in Mediterranean climates. Uptake of NO3? (μmol · g dry weight [dwt]?1 · h?1) was measured as loss from the water after 1, 2, 4, 8, 12, and 24 h and storage as total tissue nitrogen (% dwt) and nitrate (ppm). Both species of algae exhibited a high affinity for NO3? across all N pulses and initial tissue contents. There was greater NO3? removal from the water for depleted than enriched algae across all time intervals. In the low‐N‐pulse treatment, U. intestinalis and U. expansa removed all measurable NO3? within 8 and 12 h, respectively, and in the medium and high treatments, removal was high and then decreased over time. Maximum mean uptake rates of nitrate were greater for U. expansa (~300 μmol · g dwt?1 · h?1) than U. intestinalis (~100 μmol · g dwt?1 · h?1); however, uptake rates were highly variable over time. Overall, U. expansa uptake rates were double those of U. intestinalis. Maximum tissue NO3? for U. expansa was >1,000 ppm, five times that of U. intestinalis, suggesting that U. expansa has a greater storage capacity in this cellular pool. These results showed that opportunistic green algae with differing tissue nutrient histories were able to efficiently remove nitrate from the water across a wide range of N pulses; thus, both are highly adapted to proliferate in estuarine environments with pulsed nutrient supplies. 相似文献
44.
I Kogan-Sakin Y Tabach Y Buganim A Molchadsky H Solomon S Madar I Kamer P Stambolsky A Shelly N Goldfinger S Valsesia-Wittmann A Puisieux A Zundelevich E N Gal-Yam C Avivi I Barshack M Brait D Sidransky E Domany V Rotter 《Cell death and differentiation》2011,18(2):271-281
A mutation within one allele of the p53 tumor suppressor gene can inactivate the remaining wild-type allele in a dominant-negative manner and in some cases can exert an additional oncogenic activity, known as mutant p53 ‘gain of function'' (GOF). To study the role of p53 mutations in prostate cancer and to discriminate between the dominant-negative effect and the GOF activity of mutant p53, we measured, using microarrays, the expression profiles of three immortalized prostate epithelial cultures expressing wild-type, inactivated p53 or mutated p53. Analysis of these gene expression profiles showed that both inactivated p53 and p53R175H mutant expression resulted in the upregulation of cell cycle progression genes. A second group, which was upregulated exclusively by mutant p53R175H, was predominantly enriched in developmental genes. This group of genes included the Twist1, a regulator of metastasis and epithelial–mesenchymal transition (EMT). Twist1 levels were also elevated in metastatic prostate cancer-derived cell line DU145, in immortalized lung fibroblasts and in a subset of lung cancer samples, all in a mutant p53-dependent manner. p53R175H mutant bearing immortalized epithelial cells showed typical features of EMT, such as higher expression of mesenchymal markers, lower expression of epithelial markers and enhanced invasive properties in vitro. The mechanism by which p53R175H mutant induces Twist1 expression involves alleviation of the epigenetic repression. Our data suggest that Twist1 expression might be upregulated following p53 mutation in cancer cells. 相似文献
45.
Filip AM Volckaert Bart Hellemans Costas Batargias Bruno Louro Cécile Massault Jeroen KJ Van Houdt Chris Haley Dirk-Jan de Koning Adelino VM Canario 《遗传、选种与进化》2012,44(1):15
Background
In fish, the most studied production traits in terms of heritability are body weight or growth, stress or disease resistance, while heritability of cortisol levels, widely used as a measure of response to stress, is less studied. In this study, we have estimated heritabilities of two growth traits (body weight and length) and of cortisol response to confinement stress in the European sea bass.Findings
The F1 progeny analysed (n = 922) belonged to a small effective breeding population with contributions from an unbalanced family structure of just 10 males and 2 females. Heritability values ranged from 0.54 (±0.21) for body weight to 0.65 (±0.22) for standard body length and were low for cortisol response i.e. 0.08 (±0.06). Genetic correlations were positive (0.94) between standard body length and body weight and negative between cortisol and body weight and between cortisol and standard body length (−0.60 and −0.55, respectively).Conclusion
This study confirms that in European sea bass, heritability of growth-related traits is high and that selection on such traits has potential. However, heritability of cortisol response to stress is low in European sea bass and since it is known to vary greatly among species, further studies are necessary to understand the reasons for these differences. 相似文献46.
47.
Richard J van HaarenPeter H Keeven Lars A van der VeenKees Goubitz Gino P.F van StrijdonckHenk Oevering Joost N.H ReekPaul C.J Kamer Piet W.N.M van Leeuwen 《Inorganica chimica acta》2002,327(1):108-115
The regioselectivity of the palladium catalyzed allylic alkylation was studied systematically using bidentate ligands based on a xanthene backbone, bearing different donor atoms. The nature of the ligand donor atoms has a pronounced influence on the regioselectivity of the reaction. The results can be explained by a mechanism that distinguishes two ‘stages’ in the alkylation reaction. Ligands bearing strong π-acceptor donor atoms induce the formation of branched products (60% for the PP derivative), whereas the use of ligands with weak π-acceptor donor atoms mainly yields linear products (>99% for the NN derivative). 相似文献
48.
Carpio LC Stephan E Kamer A Dziak R 《Prostaglandins, leukotrienes, and essential fatty acids》1999,61(5):267-273
Ceramide, ceramide-1-phosphate (C1P) sphingosine (SPH) and sphingosine-1-phosphate (S1P) effects on proliferation and extracellular-signal regulated kinases, ERKs (also known as MAPKs), activation were investigated in human and rat osteoblastic cells. MAPK activation was sphingolipid-specific in cells from both species. In human osteoblastic cells, S1P and C1P markedly stimulated ERK2 phosphorylation with a slight increase in phosphorylation of ERK1. SPH nor ceramide induced phosphorylation of either ERK isoform. In rat osteoblastic cells, SIP, ceramide and SPH stimulated phosphorylation of both isoforms. C1P did not induce phosphorylation of ERK1 but produced a mild increase in phosphorylation of ERK2. In human cells, only S1P significantly (P<0.05) increased osteoblastic cell proliferation, while in the rat cells all four sphingolipids significantly (P<0.05) induced proliferation. The calcium channel blocker verapamil blocked (P<0.05) these effects in both cell types. The MAPK inhibitor, PD98059, inhibited (P<0.05) the mitogenic effect of SIP in human cells. In rat cells, PD98059 effects were less substantial but significant for S1P and C1P. This study demonstrates that sphingolipids are mitogens for both human and rat osteoblastic cells with the MAPK pathway and calcium mediating in part these effects in a species specific manner. 相似文献
49.
Identification of a novel hypoxia-inducible factor 1-responsive gene, RTP801, involved in apoptosis 总被引:25,自引:0,他引:25
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50.