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101.
Role of cytosolic rat liver aldehyde dehydrogenase in the oxidation of acetaldehyde during ethanol metabolism in vivo. 下载免费PDF全文
The activity of a high-Km aldehyde dehydrogenase in the liver cytosol was increased by phenobarbital induction. No corresponding increase in the oxidation rate of acetaldehyde in vivo was found, and it is concluded that cytosolic aldehyde dehydrogenase plays only a minor role in the oxidation of acetaldehyde during ethanol metabolism. 相似文献
102.
Todd J Menkhaus Sara U Eriksson Paul B Whitson Charles E Glatz 《Biotechnology and bioengineering》2002,77(2):148-154
Host selection can be a strategy to simplify downstream processing for protein recovery. Advancing capabilities for using plants as hosts offers new host opportunities that have received only limited attention from a downstream processing perspective. Here, we investigated the potential of using a polycationic precipitating agent (polyethylenimine; PEI) to precipitate an acidic model protein (beta-glucuronidase; GUS) from aqueous plant extracts. To assess the potential of host selection to enhance the ease of recovery, the same procedure was applied to oilseed extracts of canola, corn (germ), and soy. For comparison, PEI precipitation of GUS was also evaluated from a crude bacterial fermentation broth. Two versions of the target protein were investigated--the wild-type enzyme (WTGUS) and a genetically engineered version containing 10 additional aspartates on each of the enzyme's four homologous subunits (GUSD10). It was found that canola was the most compatible expression host for use with this purification technique. GUS was completely precipitated from canola with the lowest dosage of PEI (30 mg PEI/g total protein), and over 80% of the initial WTGUS activity was recovered with 18-fold purification. Precipitation from soy gave yields over 90% for WTGUS but only 1.3-fold enrichment. Corn, although requiring the most PEI relative to total protein to precipitate (210 mg PEI/g total protein for 100% precipitation), gave intermediate results, with 81% recovery of WTGUS activity and a purification factor of 2.6. The addition of aspartate residues to the target protein did not enhance the selectivity of PEI precipitation in any of the systems tested. In fact, the additional charge reduced the ability to recover GUSD10 from the precipitate, resulting in lower yields and enrichment ratios compared to WTGUS. Compared to the bacterial host, plant systems provided lower polymer dosage requirements, higher yields of recoverable activity and greater purification factors. 相似文献
103.
104.
105.
Jianghai Wang Jyoti Chattopadhyaya Staffan Eriksson 《Nucleosides, nucleotides & nucleic acids》2013,32(4-5):807-810
Abstract Cytosolic thymidine kinase (TK1) and deoxycytidine kinase (dCK) and the mitochondrial thymidine kinase (TK2) and deoxyguanosine kinase (dGK), phosphorylate deoxynucleosides and their analogs. Recombinant human TK1 only phosphorylated β-D Thd, but recombinant TK2, dCK and dGK all phosphorylated equally well β-D and β-L as well as to some extent α-D and α-L deoxynucleosides. 相似文献
106.
Magdalena Eriksson Bengt Nordeh Bengt Jernström 《Nucleosides, nucleotides & nucleic acids》2013,32(5-6):717-720
Abstract Flow linear dichroism and fluorescence spectroscopy show that the covalent (+)-anti-BPDE-DNA complex adopts two rapidly interchanging conformations. The binding introduces local flexibility in DNA facilitating further covalent attacks. 相似文献
107.
Joanna Strand Hadis Honarvar Anna Perols Anna Orlova Ram Kumar Selvaraju Amelie Eriksson Karlstr?m Vladimir Tolmachev 《PloS one》2013,8(8)
Affibody molecules are a class of small (7 kDa) non-immunoglobulin scaffold-based affinity proteins, which have demonstrated substantial potential as probes for radionuclide molecular imaging. The use of positron emission tomography (PET) would further increase the resolution and quantification accuracy of Affibody-based imaging. The rapid in vivo kinetics of Affibody molecules permit the use of the generator-produced radionuclide 68Ga (T1/2 = 67.6 min). Earlier studies have demonstrated that the chemical nature of chelators has a substantial influence on the biodistribution properties of Affibody molecules. To determine an optimal labeling approach, the macrocyclic chelators 1,4,7,10-tetraazacylododecane-1,4,7,10-tetraacetic acid (DOTA), 1,4,7-triazacyclononane-N,N,N-triacetic acid (NOTA) and 1-(1,3-carboxypropyl)-1,4,7- triazacyclononane-4,7-diacetic acid (NODAGA) were conjugated to the N-terminus of the synthetic Affibody molecule ZHER2:S1 targeting HER2. Affibody molecules were labeled with 68Ga, and their binding specificity and cellular processing were evaluated. The biodistribution of 68Ga-DOTA-ZHER2:S1,
68Ga-NOTA-ZHER2:S1 and 68Ga-NODAGA-ZHER2:S1, as well as that of their 111In-labeled counterparts, was evaluated in BALB/C nu/nu mice bearing HER2-expressing SKOV3 xenografts. The tumor uptake for 68Ga-DOTA-ZHER2:S1 (17.9±0.7%IA/g) was significantly higher than for both 68Ga-NODAGA-ZHER2:S1
(16.13±0.67%IA/g) and 68Ga-NOTA-ZHER2:S1 (13±3%IA/g) at 2 h after injection. 68Ga-NODAGA-ZHER2:S1 had the highest tumor-to-blood ratio (60±10) in comparison with both 68Ga-DOTA-ZHER2:S1 (28±4) and 68Ga-NOTA-ZHER2:S1 (42±11). The tumor-to-liver ratio was also higher for 68Ga-NODAGA-ZHER2:S1 (7±2) than the DOTA and NOTA conjugates (5.5±0.6 vs.3.3±0.6). The influence of chelator on the biodistribution and targeting properties was less pronounced for 68Ga than for 111In. The results of this study demonstrate that macrocyclic chelators conjugated to the N-terminus have a substantial influence on the biodistribution of HER2-targeting Affibody molecules labeled with 68Ga.This can be utilized to enhance the imaging contrast of PET imaging using Affibody molecules and improve the sensitivity of molecular imaging. The study demonstrated an appreciable difference of chelator influence for 68Ga and 111In. 相似文献
108.
Hanna Alastalo Mikaela B. von Bonsdorff Katri R?ikk?nen Anu-Katriina Pesonen Clive Osmond David J. P. Barker Kati Heinonen Eero Kajantie Johan G. Eriksson 《PloS one》2013,8(7)
Background
Severe stress experienced in early life may have long-term effects on adult physiological and psychological health and well-being. We studied physical and psychosocial functioning in late adulthood in subjects separated temporarily from their parents in childhood during World War II.Methods
The 1803 participants belong to the Helsinki Birth Cohort Study, born 1934–44. Of them, 267 (14.8%) had been evacuated abroad in childhood during WWII and the remaining subjects served as controls. Physical and psychosocial functioning was assessed with the Short Form 36 scale (SF-36) between 2001 and 2004. A test for trends was based on linear regression. All analyses were adjusted for age at clinical examination, social class in childhood and adulthood, smoking, alcohol intake, physical activity, body mass index, cardiovascular disease and diabetes.Results
Physical functioning in late adulthood was lower among the separated men compared to non-separated men (b = −0.40, 95% confidence interval [95% CI]: −0.71 to −0.08). Those men separated in school age (>7 years) and who were separated for a duration over 2 years had the highest risk for lower physical functioning (b = −0.89, 95% CI: −1.58 to −0.20) and (b = −0.65, 95% CI: −1.25 to −0.05), respectively). Men separated for a duration over 2 years also had lower psychosocial functioning (b = −0.70, 95% CI: −1.35 to −0.06). These differences in physical and psychosocial functioning were not observed among women.Conclusion
Early life stress may increase the risk for impaired physical functioning in late adulthood among men. Timing and duration of the separation influenced the physical and psychosocial functioning in late adulthood. 相似文献109.
Cécilia G. Maubaret Klelia D. Salpea Casey E. Romanoski Lasse Folkersen Jackie A. Cooper Coralea Stephanou Ka Wah Li Jutta Palmen Anders Hamsten Andrew Neil Jeffrey W. Stephens Aldons J. Lusis Per Eriksson Philippa J. Talmud Steve E. Humphries the Simon Broome Research Group the EARSII consortium 《PloS one》2013,8(12)
Objective
To replicate the associations of leukocyte telomere length (LTL) with variants at four loci and to investigate their associations with coronary heart disease (CHD) and type II diabetes (T2D), in order to examine possible causal effects of telomere maintenance machinery on disease aetiology.Methods
Four SNPs at three loci BICD1 (rs2630578 GγC), 18q12.2 (rs2162440 GγT), and OBFC1 (rs10786775 CγG, rs11591710 AγC) were genotyped in four studies comprised of 2353 subjects out of which 1148 had CHD and 566 T2D. Three SNPs (rs12696304 CγG, rs10936601G>T and rs16847897 GγC) at the TERC locus were genotyped in these four studies, in addition to an offspring study of 765 healthy students. For all samples, LTL had been measured using a real-time PCR-based method.Results
Only one SNP was associated with a significant effect on LTL, with the minor allele G of OBFC1 rs10786775 SNP being associated with longer LTL (β=0.029, P=0.04). No SNPs were significantly associated with CHD or T2D. For OBFC1 the haplotype carrying both rare alleles (rs10786775G and rs11591710C, haplotype frequency 0.089) was associated with lower CHD prevalence (OR: 0.77; 95% CI: 0.61–0.97; P= 0.03). The TERC haplotype GTC (rs12696304G, rs10936601T and rs16847897C, haplotype frequency 0.210) was associated with lower risk for both CHD (OR: 0.86; 95% CI: 0.75-0.99; P=0.04) and T2D (OR: 0.74; 95% CI: 0.61–0.91; P= 0.004), with no effect on LTL. Only the last association remained after adjusting for multiple testing.Conclusion
Of reported associations, only that between the OBFC1 rs10786775 SNP and LTL was confirmed, although our study has a limited power to detect modest effects. A 2-SNP OBFC1 haplotype was associated with higher risk of CHD, and a 3-SNP TERC haplotype was associated with both higher risk of CHD and T2D. Further work is required to confirm these results and explore the mechanisms of these effects. 相似文献110.
Anna U. Eriksson Christoffer Svensson Andreas H?rnblad Abbas Cheddad Elena Kostromina Maria Eriksson Nils Norlin Antonello Pileggi James Sharpe Fredrik Georgsson Tomas Alanentalo Ulf Ahlgren 《Journal of visualized experiments : JoVE》2013,(71)
By adapting OPT to include the capability of imaging in the near infrared (NIR) spectrum, we here illustrate the possibility to image larger bodies of pancreatic tissue, such as the rat pancreas, and to increase the number of channels (cell types) that may be studied in a single specimen. We further describe the implementation of a number of computational tools that provide: 1/ accurate positioning of a specimen''s (in our case the pancreas) centre of mass (COM) at the axis of rotation (AR)2; 2/ improved algorithms for post-alignment tuning which prevents geometric distortions during the tomographic reconstruction2 and 3/ a protocol for intensity equalization to increase signal to noise ratios in OPT-based BCM determinations3. In addition, we describe a sample holder that minimizes the risk for unintentional movements of the specimen during image acquisition. Together, these protocols enable assessments of BCM distribution and other features, to be performed throughout the volume of intact pancreata or other organs (e.g. in studies of islet transplantation), with a resolution down to the level of individual islets of Langerhans. 相似文献