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11.
The enantiomers of 5-dimethylamino-1-naphthalene sulfonyl (DNS)-derivatives of selected amino acids were successfully separated using capillary electrophoresis (CE) employing cyclodextrins (CD) as enantio-selective running buffer additives. A previously described model for retention and chiral recognition in CD-modified CE is shown to adapt well in this application. Resolution of the isomers is strongly influenced by the type and concentration of cyclodextrin employed, as predicted by the model. Although data indicates differences in the electrophoretic mobilities for some of the completely complexed enantiomer pairs, selectivity generally requires exploiting differences in the amino acid-CD complexation constants for enantiomer pairs. In this work, the D-enantiomers exhibit larger formation constants and are complexed to a greater degree (elute first) at moderate CD concentration. When mixtures of amino acids are analyzed, the effects of separation conditions on general elution behavior must be considered or separated enantiomer pairs will co-elute with other enantiomers. Preliminary results aimed at predicting the strength of DNS-amino acid enantiomer-CD interactions based on molecular modeling studies are presented. A statistical mechanical approach to treating computationally derived enantiomer-CD interaction energies is shown to provide reasonable correlation with separation performance. 相似文献
12.
Resistance-modifying agents (RMAs) such as Verapamil have been proved to be effective in reversing multi-drug resistance (MDR) in many in vitro assays. In this study we have investigated the efficacy of Dex-Verapamil, the R-isomer of Verapamil, as a chemosensitizer in a murine leukemia cell line (P388) and in its resistant counterpart (P388/Dx) expressing a typical MDR phenotype. We have examined in vivo the effect of the co-administration of Dex-Verapamil and Doxorubicin in mice transplanted with P388 or P388/Dx cells. Mice treated with the combination of Doxorubicin plus RMA had a significant increase in survival rate as compared to controls; however, the effect was modest. On the contrary, in vitro Dex-Verapamil can enhance Doxorubicin cytotoxicity in P388/Dx cells with a much greater effect depending on the treatment scheme used, by increasing the intracellular content of drug. Taken together our data indicate that Dex-Verapamil can indeed increase the sensitivity to Doxorubicin in resistant cells, but the limited efficacy shown in vivo demonstrates that this phenomenon is strongly dependent on the treatment scheme used and on the maintenance of constantly elevated serum levels. 相似文献
13.
14.
Four women aged 30, 29, 52 and 43 years presented with what appeared to be subacute thyroiditis (De Quervain's thyroiditis). This disease is characterized by fatigue, a painful thyroid gland and thyrotoxic manifestations. The diagnosis is further based on a high erythrocyte sedimentation rate and low tracer uptake during thyroid scintigraphy. Only the first patient showed a typical course. In the second and third ones the painful thyroid was associated with nodular enlargement. Fine needle aspiration cytology was at first consistent with subacute thyroiditis but a repeated aspiration showed papillary carcinoma in the second and anaplastic carcinoma in the third patient. In the fourth one, subacute thyroiditis was accompanied by normochromic anaemia, a low serum albumin concentration and liver function disorders. She made a full recovery without treatment. Thyroid malignancies can mimic subacute thyroiditis. Persistent nodular enlargement of the thyroid is suspicious and requires careful investigation. 相似文献
15.
Gold Nanorods,DNA Origami,and Porous Silicon Nanoparticle‐functionalized Biocompatible Double Emulsion for Versatile Targeted Therapeutics and Antibody Combination Therapy
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16.
Engineered Multifunctional Albumin‐Decorated Porous Silicon Nanoparticles for FcRn Translocation of Insulin
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João P. Martins Roberto D'Auria Dongfei Liu Flavia Fontana Mónica P. A. Ferreira Alexandra Correia Marianna Kemell Karina Moslova Ermei Mäkilä Jarno Salonen Luca Casettari Jouni Hirvonen Bruno Sarmento Hélder A. Santos 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(27)
The last decade has seen remarkable advances in the development of drug delivery systems as alternative to parenteral injection‐based delivery of insulin. Neonatal Fc receptor (FcRn)‐mediated transcytosis has been recently proposed as a strategy to increase the transport of drugs across the intestinal epithelium. FcRn‐targeted nanoparticles (NPs) could hijack the FcRn transcytotic pathway and cross the epithelial cell layer. In this study, a novel nanoparticulate system for insulin delivery based on porous silicon NPs is proposed. After surface conjugation with albumin and loading with insulin, the NPs are encapsulated into a pH‐responsive polymeric particle by nanoprecipitation. The developed NP formulation shows controlled size and homogeneous size distribution. Transmission electron microscopy (TEM) images show successful encapsulation of the NPs into pH‐sensitive polymeric particles. No insulin release is detected at acidic conditions, but a controlled release profile is observed at intestinal pH. Toxicity studies show high compatibility of the NPs with intestinal cells. In vitro insulin permeation across the intestinal epithelium shows approximately fivefold increase when insulin is loaded into FcRn‐targeted NPs. Overall, these FcRn‐targeted NPs offer a toolbox in the development of targeted therapies for oral delivery of insulin. 相似文献
17.
JW Lynch GA Kaplan RD Cohen J Tuomilehto JT Salonen 《Canadian Metallurgical Quarterly》1996,144(10):934-942
Much remains to be understood about how low socioeconomic status (SES) increases cardiovascular disease and mortality risk. Data from the Kuopio Ischemic Heart Disease Risk Factor Study (1984-1993) were used to estimate the associations between acute myocardial infarction and income, all-cause mortality, and cardiovascular mortality in a population-based sample of 2,272 Finnish men, with adjustment for 23 biologic, behavioral, psychologic, and social risk factors. Compared with the highest income quintile, those in the bottom quintile had age-adjusted relative hazards of 3.14 (95% confidence interval (CI) 1.77-5.56), 2.66 (95% CI 1.25-5.66), and 4.34 (95% CI 1.95-9.66) for all-cause mortality, cardiovascular mortality, and AMI, respectively. After adjustment for risk factors, the relative hazards for the same comparisons were 1.32 (95% CI 0.70-2.49), 0.70 (95% CI 0.29-1.69), and 2.83 (95% CI 1.14-7.00). In the lowest income quintile, adjustment for risk factors reduced the excess relative risk of all-cause mortality by 85%, that of cardiovascular mortality by 118%, and that of acute myocardial infarction by 45%. These data show how the association between SES and cardiovascular mortality and all-cause mortality is mediated by known risk factor pathways, but full "explanations" for these associations will need to encompass why these biologic, behavioral, psychologic, and social risk factors are differentially distributed by SES. 相似文献
18.
Tuomas Alapieti Emmanuelle Castagnoli Laura Salo Raimo Mikkola Pertti Pasanen Heidi Salonen 《Indoor air》2021,31(5):1563-1576
The emissions of volatile organic compounds (VOCs) from building materials may significantly contribute to indoor air pollution, and VOCs have been associated with odor annoyance and adverse health effects. Wood materials together with coatings are commonly used indoors for furniture and large surfaces such as walls, floors, and ceilings. This leads to high surface-to-volume ratios, and therefore, these materials may participate remarkably to the VOC levels of indoor environment. We studied emissions of VOCs and carbonyl compounds from pinewood (Pinus sylvestris) boards of 10% and 16% moisture contents (MC) with three paints using small-scale test chambers (27 L). The emissions from uncoated pinewood and paints (on a glass substrate) were tested as references. The 28-day experiment showed that the VOC emissions from uncoated pinewood were lower from sample with 16% MC. Painted pinewood samples showed lower emissions compared to paints on glass substrate. Additionally, paints on 16% MC pinewood exhibited lower emissions than on drier 10% MC wood. The emissions from painted pinewood samples were dominated by paint-based compounds, but the share of wood-based compounds increased over time. However, we noticed differences between the paints, and wood-based emissions were clearly higher with the most permeable paint. 相似文献
19.
Christian Wolkersdorfer Rob Bowell Ingar F. Walder Steinar Nilssen Marja Liisa R?is?nen P?ivi Heikkinen Kari Pulkkinen Kirsti Korkka-Niemi Veli-Pekka Salonen Georgia Destouni Andrea Hasche Andrzej J. Witkowski A. Blachère S. Morel D. Lefort Sanda Mid?i? Irem Silajd?i? R. H. Coulton K. P. Williams Ben Rees Kevin B. Hallberg D. Barrie Johnson 《Mine Water and the Environment》2012,31(3):237-238
20.
Outi Sipil A. Visa O. Salonen T. Erkinjuntti T. Katila 《Pattern recognition letters》2001,22(14):1475-1482
Automatic intensity-based tissue classification sets requirements for the quality of multispectral magnetic resonance (MR) images. Tests for evaluating the separability of tissue classes, and on the other hand class distances required to obtain reliable classification, are presented in this study. Intraslice, interslice and interpatient training schemes for 5-nn classification were considered. Interslice training was utilized in classification of images from 10 patients with ischemic stroke giving results of satisfactory but highly variable quality. Based on the experience with these data sets, similar tests are recommended before imaging a large patient series in order to avoid extra manual work and to obtain reliable classification results. 相似文献