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91.
Inabilities to process particulate material and to allow the use of high flow rates are limitations of conventional chromatography. Membranes have been suggested as matrix for affinity separation due to advantages such as allowing high flow rates and low-pressure drops. This work evaluated the feasibility of using an iminodiacetic acid linked poly(ethylenevinyl alcohol) membrane in the immobilized metal ion affinity chromatography (IMAC) purification of a human proinsulin(His)(6) of an industrial insulin production process. The screening of metal ions showed Ni(2+) as metal with higher selectivity and capacity among the Cu(2+), Ni(2+), Zn(2+) and Co(2+). The membrane showed to be equivalent to conventional chelating beads in terms of selectivity and had a lower capacity (3.68 mg/g versus 12.26 mg/g). The dynamic adsorption capacity for human proinsulin(His)(6) was unaffected by the mode of operation (dead-end and cross-flow filtration).  相似文献   
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Previous research on histamine H3 antagonists has led to the development of a pharmacophore model consisting of a central phenyl core flanked by two alkylamine groups. Recent investigation of the replacement of the central phenyl core with heteroaromatic fragments resulted in the preparation of novel 3,5-, 3,6- and 3,7-substituted indole and 3,5-substituted benzothiophene analogs that demonstrate good to excellent hH3 affinities. Select analogs were profiled in a rat pharmacokinetic model.  相似文献   
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The pre-clinical characterization of novel aryloxypyridine amides that are histamine H3 receptor antagonists is described. These compounds are high affinity histamine H3 ligands that penetrate the CNS and occupy the histamine H3 receptor in rat brain. Several compounds were extensively profiled pre-clinically leading to the identification of two compounds suitable for nomination as development candidates.  相似文献   
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Previous studies have shown that lipids are transferred from lymphocytes (Ly) to different cell types including macrophages, enterocytes, and pancreatic β cells in co‐culture. This study investigated whether [14C]‐labeled fatty acids (FA) can be transferred from Ly to skeletal muscle (SM), and the effects of exercise on such phenomenon. Ly obtained from exercised (EX) and control (C) male Wistar rats were preloaded with the [14C]‐labeled free FA palmitic (PA), oleic (OA), linoleic (LA), or arachidonic (AA). Radioactively loaded Ly were then co‐cultured with SM from the same Ly donor animals. Substantial amounts of FA were transferred to SM being the profile PA = OA > AA > LA to the C group, and PA > OA > LA > AA to the EX group. These FA were incorporated predominantly as phospholipids (PA = 66.75%; OA = 63.09%; LA = 43.86%; AA = 47.40%) in the C group and (PA = 63.99% OA = 52.72%; LA = 55.99%; AA = 63.40%) in the EX group. Also in this group, the remaining radioactivity from AA, LA, and OA acids was mainly incorporated in structural and energetic lipids. These results support the hypothesis that Ly are able to export lipids to SM in co‐culture. Furthermore, exercise modulates the lipid transference profile, and its incorporation on SM. The overall significance of this phenomenon in vivo remains to be elucidated. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
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Background

Despite the growing awareness of the necessity of a sustainable development, the global economy continues to depend largely on the consumption of non-renewable energy resources. One such energy resource is fossil oil extracted from the seabed at offshore oil platforms. This type of oil production causes continuous environmental pollution from drilling waste, discharge of large amounts of produced water, and accidental spills.

Methods and principal findings

Samples from natural populations of haddock (Melanogrammus aeglefinus) and Atlantic cod (Gadus morhua) in two North Sea areas with extensive oil production were investigated. Exposure to and uptake of polycyclic aromatic hydrocarbons (PAHs) were demonstrated, and biomarker analyses revealed adverse biological effects, including induction of biotransformation enzymes, oxidative stress, altered fatty acid composition, and genotoxicity. Genotoxicity was reflected by a hepatic DNA adduct pattern typical for exposure to a mixture of PAHs. Control material was collected from a North Sea area without oil production and from remote Icelandic waters. The difference between the two control areas indicates significant background pollution in the North Sea.

Conclusion

It is most remarkable to obtain biomarker responses in natural fish populations in the open sea that are similar to the biomarker responses in fish from highly polluted areas close to a point source. Risk assessment of various threats to the marine fish populations in the North Sea, such as overfishing, global warming, and eutrophication, should also take into account the ecologically relevant impact of offshore oil production.  相似文献   
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Prenatal ethanol exposure is the leading preventable cause of congenital mental disability. Whereas a diagnosis of fetal alcohol syndrome (FAS) requires identification of a specific pattern of craniofacial dysmorphology, most individuals with behavioral and neurological sequelae of heavy prenatal ethanol exposure do not exhibit these defining facial characteristics. Here, a novel integration of MRI and dense surface modeling-based shape analysis was applied to characterize concurrent face-brain phenotypes in C57Bl/6J fetuses exposed to ethanol on gestational day (GD)7 or GD8.5. The facial phenotype resulting from ethanol exposure depended upon stage of insult and was predictive of unique patterns of corresponding brain abnormalities. Ethanol exposure on GD7 produced a constellation of dysmorphic facial features characteristic of human FAS, including severe midfacial hypoplasia, shortening of the palpebral fissures, an elongated upper lip, and deficient philtrum. In contrast, ethanol exposure on GD8.5 caused mild midfacial hypoplasia and palpebral fissure shortening, a shortened upper lip, and a preserved philtrum. These distinct, stage-specific facial phenotypes were associated with unique volumetric and shape abnormalities of the septal region, pituitary, and olfactory bulbs. By demonstrating that early prenatal ethanol exposure can cause more than one temporally-specific pattern of defects, these findings illustrate the need for an expansion of current diagnostic criteria to better capture the full range of facial and brain dysmorphology in fetal alcohol spectrum disorders.  相似文献   
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