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41.
Idriss Bennacef Cristian A. Salinas Thomas A. Bonasera Roger N. Gunn Hélène Audrain Steen Jakobsen Nabeel Nabulsi David Weinzimmer Richard E. Carson Yiyun Huang Ian Holmes Fabrizio Micheli Christian Heidbreder Gabriella Gentile Tino Rossi Marc Laruelle 《Bioorganic & medicinal chemistry letters》2009,19(17):5056-5059
Compound 1 is a potent and selective antagonist of the dopamine D3 receptor. With the aim of developing a carbon-11 labeled ligand for the dopamine D3 receptor, 1 was selected as a potential PET probe. [11C]1 was obtained by palladium catalyzed cross coupling using [11C]cyanide and 4 with a specific activity of 55.5 ± 25.9 GBq/μmol (1.5 ± 0.7 Ci/μmol). [11C]1 was tested in porcine and non-human primate models to assess its potential as a radioligand for PET imaging of the dopamine D3 receptor. We conclude that in both species and despite appropriate in vitro properties, [11C]1 does not show any specific signal for the dopamine D3 receptor. 相似文献
42.
When exponentially growing KB cells were deprived of arginine, cell multiplication ceased after 12 h but viability was maintained throughout the experimental period (42-48 h). Although tritiated thymidine ([(3)H]TdR) incorporation into acid-insoluble material declined to 5 percent of the initial rate, the fraction of cells engaged in DNA synthesis, determined by autoradiography, remained constant throughout the starvation period and approximately equal to the synthesizing fraction in exponentially growing controls (40 percent). Continous [(3)H]TdR-labeling indicated that 80 percent of the arginine-starved cells incorporated (3)H at some time during a 48-h deprivation period. Thus, some cells ceased DNA synthesis, whereas some initially nonsynthesizing cells initiated DNA synthesis during starvation. Flow microfluorometric profiles of distribution of cellular DNA contents at the end of the starvation period indicated that essentially no cells had a 4c or G2 complement. If arginine was restored after 30 h of starvation, cultures resumed active, largely asynchronous division after a 16-h lag. Autoradiographs of metaphase figures from cultures continuously labeled with [(3)H]TdR after restoration indicated that all cells in the culture underwent DNA synthesis before dividing. It was concluded that the majority of cells in arginine-starved cultures are arrested in neither a normal G1 nor G2. It is proposed that for an exponential culture, i.e. from most positions in the cell cycle, inhibition of cell growth after arginine with withdrawal centers on the ability of cells to complete replication of their DNA. 相似文献
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44.
C. A. Salinas D. A. R. Sinclair K. O''Hare H. W. Brock 《Molecular & general genetics : MGG》1998,257(6):672-680
Processing of the 3′ end of mRNA precursors depends on several proteins. The multisubunit cleavage and polyadenylation specificity
factor (CPSF) is required for cleavage of the mRNA precursor as well as polyadenylation. CPSF interacts with the cleavage
stimulatory factor complex (CstF), and this interaction increases the specificity of binding. Following cleavage downstream
of the AAUAAA site, CPSF and poly(A) polymerase (PAP) are required for efficient polyadenylation. Recently, it has been shown
that 160-kDa subunit of CPSF interacts directly with the 77-kDa subunit of CstF, which is homologous to the product encoded
by the Drosophila gene su(f), and with PAP. Here we report the cloning and characterization of a Drosophila homologue of CPSF-160. The 1329-amino acid dCPSF protein exhibits about 45% and 20% sequence identity, respectively, to its
mammalian and yeast counterparts over its entire length. We show that the CPSF homologue is expressed throughout development
and that CPSF is essential for viability. Mutations in the cpsf gene did not alter the phenotype of homozygous su(f) mutations, suggesting that, for most genes, processing of 3′ termini is not sensitive to small changes in cpsf and su(f) dosage.
Received: 6 June 1997 / Accepted: 5 November 1997 相似文献
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Thioredoxin and glutathione systems are the major thiol-dependent redox systems in animal cells. They transfer via the reversible oxidoreduction of thiols the reducing equivalents of NADPH to numerous substrates and substrate reductases and constitute major defenses against oxidative stress. In this study, we cloned from the helminth parasite Echinococcus granulosus two trans-spliced mRNA variants that encode thioredoxin glutathione reductases (TGR). These variants code for mitochondrial and cytosolic selenocysteine-containing isoforms that possess identical glutaredoxin (Grx) and thioredoxin reductase (TR) domains and differ exclusively in their N termini. Western blot analysis of subcellular fractions with specific anti-TGR antibodies showed that TGR is present in both compartments. The biochemical characterization of the native purified TGR suggests that the Grx and TR domains of the enzyme can function either coupled or independently of each other, because the Grx domain can accept electrons from either TR domains or the glutathione system and the TR domains can transfer electrons to either the fused Grx domain or to E. granulosus thioredoxin. 相似文献
47.
Solar radiation and functional traits explain the decline of forest primary productivity along a tropical elevation gradient 下载免费PDF全文
Nikolaos M. Fyllas Lisa Patrick Bentley Alexander Shenkin Gregory P. Asner Owen K. Atkin Sandra Díaz Brian J. Enquist William Farfan‐Rios Emanuel Gloor Rossella Guerrieri Walter Huaraca Huasco Yoko Ishida Roberta E. Martin Patrick Meir Oliver Phillips Norma Salinas Miles Silman Lasantha K Weerasinghe Joana Zaragoza‐Castells Yadvinder Malhi 《Ecology letters》2017,20(6):730-740
One of the major challenges in ecology is to understand how ecosystems respond to changes in environmental conditions, and how taxonomic and functional diversity mediate these changes. In this study, we use a trait‐spectra and individual‐based model, to analyse variation in forest primary productivity along a 3.3 km elevation gradient in the Amazon‐Andes. The model accurately predicted the magnitude and trends in forest productivity with elevation, with solar radiation and plant functional traits (leaf dry mass per area, leaf nitrogen and phosphorus concentration, and wood density) collectively accounting for productivity variation. Remarkably, explicit representation of temperature variation with elevation was not required to achieve accurate predictions of forest productivity, as trait variation driven by species turnover appears to capture the effect of temperature. Our semi‐mechanistic model suggests that spatial variation in traits can potentially be used to estimate spatial variation in productivity at the landscape scale. 相似文献
48.
Rafael Bielza Galindo Alejandro Ortiz Espada Estefanía Arias Muñana Rocío Velasco Guzmán de Lázaro Asunción Mora Casado Ricardo Moreno Martín Blanca Tapia Salinas Javier Escalera Alonso Jorge Gómez Cerezo 《Revista espa?ola de geriatría y gerontología》2013
Background
Patients with hip fracture (HF), due to their characteristics, require a specific support. The Acute Orthogeriatric Unit (OGU) has been shown to be one of the most beneficial.Objective
To evaluate the main variables of HF patients treated at an OGU and compare them with the previous referral model (RC).Material and methods
A prospective observational study with retrospective control was conducted on 169 patients, split into two groups. In the RC group, patients were admitted to conventional trauma ward. In the OGU group, an early geriatric assessment was performed, and patients were simultaneously attended daily by the orthopaedic surgeon, nurse and geriatrician, and the surgery times, work load, discharge and destination, were planned in a weekly meeting with the rest of professionals.Results
A total of 71 patients were included in the RC group and 96 in the OGU group. The preoperative characteristics were similar, except for a slightly higher comorbidity in the OGU group. The OGU patients were operated on earlier (3.82±2.08 vs 4.61±2.5 days; P<.32), and overall hospital stay was reduced by 28% (11.84±4.04 vs 16.46±8.4 days; P<.001). The functional efficiency (Barthel Index at discharge-Barthel Index at admission/overall stay - stay before surgery) was higher in the OGU group (1.56±0.7 vs 2.61±1.1; P<.05). There were no differences in functional status, mortality or discharge location.Conclusions
The OGU is a level of care that provides effective medical care in HF patients in general hospitals. 相似文献49.
Gema López-Torrejón Davide Guerra Rafael Catal Julio Salinas Juan C. del Pozo 《植物学报(英文版)》2013,55(1):96-107
Post-translational modifications (PTMs) chemically and physically alter the properties of proteins, including their folding, subcellular localization, stability, activity, and consequently their function. In spite of their relevance, studies on PTMs in plants are still limited. Small Ubiquitin-like Modifier (SUMO) modification regulates several biological processes by affecting protein-protein interactions, or changing the subcellular localizations of the target proteins. Here, we describe a novel proteomic approach to identify SUMO targets that combines 2-D liquid chromatography, immunodetection, and mass spectrometry (MS) analyses. We have applied this approach to identify nuclear SUMO targets in response to heat shock. Using a bacterial SUMOylation system, we validated that some of the targets identified here are, in fact, labeled with SUMO1. Interestingly, we found that GIGANTEA (GI), a photoperiodic-pathway protein, is modified with SUMO in response to heat shock both in vitro and in vivo. 相似文献
50.