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991.
992.
Görman U 《Genes & nutrition》2006,1(1):13-22
Four principles are taken as basis for the ethical analysis: autonomy, nonmaleficence, beneficence, and justice. Health is understood as a limited aspect of wellbeing. Food is understood as an important aspect of wellbeing, not only an instrument for health. Modern society is characterized by a tendency to identify wellbeing with external rather than subjective circumstances, to identify wellbeing with health, and to create exaggerated health expectations. Based upon this understanding, aspects of personalized nutrition are discussed: genetic testing, counselling, and development of special dietary products. Today the predictive value of genetic tests for personal nutrition is limited, and experimental at best. Recommendations for the future: Personalized nutrition must be based on solid knowledge. Phenotypic analyses should be used when adequate. When a genetic test can have a clear advantage, this should be preferred. Opportunistic screening should only be used when clearly beneficial. Specially trained persons should collect information from genetic tests and carry through councelling on a personal basis. Marketing of genetic tests directly sold to the public should be discouraged. Development of special products for personalized nutrition may be necessary in some cases. However, this may also lead to a medicalization of diet. 相似文献
993.
Alanentalo T Chatonnet F Karlen M Sulniute R Ericson J Andersson E Ahlgren U 《Gene expression patterns : GEP》2006,6(2):162-170
Members of the Nkx family of homeodomain proteins are involved in a variety of developmental processes such as cell fate determination in the CNS and in the pancreas. Here we describe the cloning and developmental expression pattern of Nkx6.3, a new member of the Nkx6 subfamily of homeodomain proteins. Nkx6.3 is expressed in the developing CNS and gastro-intestinal tract. In contrast to Nkx6.1 and Nkx6.2 that are broadly expressed in ventral positions of the developing CNS, Nkx6.3 shows a remarkably selective expression in a subpopulation of differentiating V2 neurons at caudal hindbrain levels. The expression of Nkx6.3 at this level depends on the activity of other Nkx6 proteins. In the gut, Nkx6.3 is expressed in duodenal and glandular stomach endoderm and at the end of gestation Nkx6.3 became restricted to the base of the gastric units in the glandular stomach. The expression of Nkx6.3 overlapped with the expression of Nkx6.2 both in the CNS and in the gut. Transient Nkx6.2 expression was also detected in the developing pancreas. However, analysis of Nkx6.2(-/-) mice did not display any obvious aberrations of pancreatic or stomach development. 相似文献
994.
Niemeyer P Krause U Kasten P Kreuz PC Henle P Südkam NP Mehlhorn A 《Current stem cell research & therapy》2006,1(1):21-27
Mesenchymal stem cells (MSC) can be obtained from human bone marrow aspirates and, thanks to their differentiation potential and excellent in vitro culture properties, represent an attractive cell line for the regeneration of mesenchymal tissue. Both in vitro and in vivo, they can differentiate into cartilage, bone, tendons and fat cells, and-in contrast to embryonic stem cells-they are not under ethical scrutiny. Cultured on three-dimensional scaffolds according to the tissue engineering concept, they have already been successfully employed for reconstruction of mesenchymal tissues in numerous studies involving both small and large animal models. Recently, immunological properties of MSC have been investigated by several groups. On the basis of the available literature, MSC have to be referred to as immune privileged, and they seem to be available for HLA-independent cell transplantation. While clinical MSC transplantation has also been successfully performed in pilot studies in humans, numerous points still remain to be clarified, underscoring the need for further intensive research before large-scale clinical application can be contemplated. Only then can it be shown whether the associated high expectations are justified. 相似文献
995.
Lexander H Hellman U Palmberg C Auer G Hellström M Franzén B Jörnvall H Egevad L 《Proteomics》2006,6(13):3918-3925
For laboratory techniques that require well-preserved proteins, such as 2-DE, fresh tissue must be harvested and processed as fast as possible to avoid proteolytic degradation. We describe a modified method for harvesting tissue from radical prostatectomy specimens for proteome analysis and compare it with the standard technique. Cells were scraped from cut surfaces of 11 prostate specimens. A fraction of the material was smeared on a glass slide and Giemsa stained for morphological control. The sample was collected in a medium with protease inhibitors, and the protein material was prepared for 2-DE. Filtering and Percoll centrifugation were omitted. Sample locations were noted on a specimen map. From the same area, a tissue block was harvested for comparison. The block was processed with the conventional technique including mechanical disintegration, filtering and Percoll centrifugation. Quality measures of 2-DE were similar with both methods. With the scrape sampling technique, control smears showed abundant epithelial cells and a cleaner background and processing was faster than with tissue block sampling. For proteomic analysis, the scrape sample technique has several advantages over the tissue block method. 相似文献
996.
997.
The goal of high-throughput screening (HTS) from the perspective of the biologist is to identify a highly specific small molecule that can be used to inhibit a protein in its normal biological context. Although several useful small molecules have been identified with HTS, there are many challenges to be considered when contemplating a screen, especially by those unfamiliar with chemical biology. 相似文献
998.
Are aliens threatening European aquatic coastal ecosystems? 总被引:2,自引:2,他引:0
Inshore waters of European coasts have accumulated a high share of non-indigenous species, where a changeable palaeoenvironment has caused low diversity in indigenous biota. Also strongly transformed modern coastal ecosystems seem to assimilate whatever species have been introduced and tolerate the physical regime. Adding non-native species does not have any directional predetermined effects on recipient coastal ecosystems. The status of being a non-native rather refers to a position in evolutionary history than qualify as an ecological category with distinct and consistent properties. Effects of invaders vary between habitats and with the phase of invasion and also with shifting ambient conditions. Although aliens accelerate change in European coastal biota, we found no evidence that they generally impair biodiversity and ecosystem functioning. More often, invaders expand ecosystem functioning by adding new ecological traits, intensifying existing ones and increasing functional redundancy. 相似文献
999.
1000.
Protein kinase CK2 (former name: "casein kinase 2") is a pivotal and ubiquitously expressed member of the eukaryotic protein kinase superfamily. It predominantly exists as a heterotetrameric holoenzyme composed of two catalytic subunits (CK2alpha) and two regulatory subunits (CK2beta). In higher animals two paralog catalytic chains-abbreviated CK2alpha and CK2alpha'--exist which can combine with CK2beta to three isoforms of the holoenzyme: CK2alpha(2)beta(2), CK2alpha(2)(')beta(2), and CK2alphaalpha(')beta(2). While CK2alpha and the "normal" holoenzyme CK2alpha(2)beta(2) have been extensively characterized in vitro and in vivo, little is known about the enzymological properties of CK2alpha' and the "alternative" holoenzyme CK2alpha(2)(')beta(2) and about their specific physiological roles. A major reason for this lack of knowledge is the fact that so far CK2alpha' rather than CK2alpha has caused serious stability and solubility problems during standard heterologous expression procedures. To overcome them, we developed a preparation scheme for CK2alpha(2)(')beta(2) from Homo sapiens in catalytically active form based on two critical steps: first expression of human CK2alpha' as a well soluble fusion protein with the maltose binding protein (MBP) and second proteolytic cleavage of CK2alpha'-MBP in the presence of human CK2beta so that CK2alpha' subunits are incorporated into holoenzyme complexes directly after their release from MBP. This successful strategy which may be adopted in comparably difficult cases of protein/protein complex preparation is presented here together with evidence that the CK2alpha'-based and the CK2alpha-based holoenzymes are similar concerning their catalytic activities but are significantly different with respect to some well-known CK2 properties like autophosphorylation and supra-molecular aggregation. 相似文献