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1.
The authors analyse and assess the Universal Draft Declaration on Bioethics and Human Rights published by UNESCO. They argue that the Draft has two main weaknesses. It unnecessarily confines the scope of bioethics to life sciences and their practical applications. And it fails to spell out the intended role of human dignity in international ethical regulation.  相似文献   

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Sherwin S 《Bioethics》1999,13(3-4):198-205
I explore the implications of the foundation metaphor for understanding the role of moral theories in ethics and bioethics and argue that its disadvantages outweigh its advantages. I then consider two other metaphors that might be used instead, those of frameworks and lenses. I propose that the metaphor of lenses is most promising in providing methodological guidance for drawing on moral theories when deliberating about bioethical problems.  相似文献   

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With human genetic technologies now an important area of European research and development, bioethics is becoming increasingly important in its regulation and future. As regulatory decisions are also statements about who should get what, bioethics cannot avoid political controversy. Can bioethics sustain its claimed role as authoritative adviser to decision makers, or will its attempts to reach a consensus on human genetic technologies be perceived as the actions of an ambitious interest group? What, in short, is its political future in Europe and elsewhere?  相似文献   

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Indolethylamine N-methyltransferase (INMT) catalyzes the N-methylation of tryptamine and structurally related compounds. We recently cloned and characterized the rabbit INMT cDNA and gene as a step toward cloning the cDNA and gene for this enzyme in humans. We have now used a PCR-based approach to clone a human INMT cDNA that had a 792-bp open reading frame that encoded a 263-amino-acid protein 88% identical in sequence to rabbit INMT. Northern blot analysis of 35 tissues showed that a 2.7-kb INMT mRNA species was expressed in most tissues. When the cDNA was expressed in COS-1 cells, the recombinant enzyme catalyzed the methylation of tryptamine with an apparent K(m) value of 2.9 mM. The human cDNA was then used to clone the human INMT gene from a human genomic BAC library. The gene was 5471 bp in length, consisted of three exons, and was structurally similar to the rabbit INMT gene as well as genes for nicotinamide N-methyltransferase and phenylethanolamine N-methyltransferase in several species. All INMT exon-intron splice junctions conformed to the "GT-AG" rule, and no canonical TATA or CAAT sequences were present within the 5'-flanking region of the gene. Human INMT mapped to chromosome 7p15.2-p15.3 on the basis of both PCR analysis and fluorescence in situ hybridization. Finally, two possible single nucleotide polymorphisms were identified within exon 3, both of which altered the encoded amino acid. The cloning and expression of a human INMT cDNA, as well as the cloning, structural characterization, and mapping of its gene represent steps toward future studies of the function and regulation of this methyltransferase enzyme in humans.  相似文献   

8.
Hamano K 《Bioethics》1997,11(3-4):328-335
The main contentions of this paper are twofold. First, there is a more than century-old Japanese tradition of human rights based on a fusion of Western concepts of natural rights and a radical reinterpretation of Confucianism, the major proponent of which was the Japanese thinker Nakae Chomin. Secondly, this tradition, although a minority view, is crucial for remedying the serious defects in the present Japanese medical system.
In the latter half of the nineteenth century, Nakae Chomin sought to reinterpret Chinese tradition, especially Confucianism, by injecting the concepts of popular sovereignty and democratic equality, drawn from Western sources. The resulting view maintained the Confucian commitment to a moral nexus for society, but replaced hierarchy with egalitarianism.
The pressing need for such an approach to patients' rights in present-day Japan is illustrated by two recent cases: the photographing and commercial exploitation of patients' genitals without serious response by authorities, and the attempt by physicians to manipulate the time of death and, possibly, to improperly pressure family members in order to transplant organs from the brain-dead victim of a criminal assault.
Such problems stem from hierarchy and paternalism, which seem to be a legacy of the rapid, state-sponsored introduction of Western medicine in the mid-nineteenth century, and in particular from the government's adoption of and support for German military medicine as a model for Japan.  相似文献   

9.
We isolated a cDNA encoding liver catalase from a human liver cDNA library. The cDNA had a high degree of sequence similarity to the corresponding enzyme from other sources. It was expressed in E. coli using the pET15b vector. The protein produced was enzymatically active after purification, and its kinetic parameters closely resembled those of other mammalian catalases. Monoclonal antibodies were generated against the purified catalase; six antibodies recognizing different epitopes were obtained, one of which inhibited the enzyme. The cross reactions of the antibodies with brain catalases from human and other mammalian tissues were investigated, and all the immunoreactive bands obtained on Western blots had molecular masses of about 58 kDa. Similarly fractionated extracts of several mammalian cell lines all gave a single band of molecular mass 58 kDa. These results indicate that mammalian livers and human cell lines contain only one major type of immunologically reactive catalase, even though some of catalases have been previously reported to differ in certain properties.  相似文献   

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Species: the concept, category and taxon   总被引:2,自引:0,他引:2  
The term species by itself is vague because it refers to the species concept, the species category and the species taxon, all of which are distinct although related to one another. The species concept is not primarily a part of systematics, but has always been an integral part of basic biological theory, It is based on evolutionary theory and applies only to sexually reproducing organisms. The species concept and the phyletic lineage concept are quite distinct although they are related to one another. The important aspect of the species concept is lack of gene flow between different species, and hence the defining criterion of the species is genetic isolation. The species concept is often considered as non‐dimensional, both in time and space. Species possess three different major properties, namely genetic isolation, reproductive isolation and ecological isolation; these properties evolve at different times and under the effect of different causes during the speciation process. Speciation requires an external isolating barrier during the initial allopatric phase in which genetic isolation evolves and must reach 100% efficiency. The subsequent sympatric phase of speciation occurs after the disappearance of the external isolating barrier when members of the two newly evolved species can interact with one another and exert mutual selective demands on one another. Much of the reproductive and ecological isolation evolves during this secondary sympatric phase. The species category is a rank in the taxonomic hierarchy and serves as the basis on which the diversity of organisms is described; it is not the same as the species concept. The species category applied to all organisms, sexually and asexually reproducing. The species taxon is the practical application of the species category in systematics with the recognition of species taxa requiring many arbitrary decisions. No single set of rules exist by which the species category can be applied to all organisms. Recognition of species taxa in asexually reproducing organisms is based on amount of variation and gaps in the variation of phenotypic features associated with ecological attributes of these organisms as compared with similar attributes in sympatric species taxa of sexually reproducing organisms. Species taxa are multidimensional in that they exist over space–time and often have fuzzy borders. Because recognition of species taxa, including those in sexually reproducing organisms, depends on many arbitrary decisions especially when dealing with broad geographical and temporal ranges, species taxa cannot be used as the foundation for developing and testing theoretical concepts in evolutionary theory which can only be done with the non‐dimensional species concept.  相似文献   

12.
A 2112-bp cDNA clone (lambda CT29) encoding the entire sequence of the human lysosomal acid phosphatase (EC 3.1.3.2) was isolated from a lambda gt11 human placenta cDNA library. The cDNA hybridized with a 2.3-kb mRNA from human liver and HL-60 promyelocytes. The gene for lysosomal acid phosphatase was localized to human chromosome 11. The cDNA includes a 12-bp 5' non-coding region, an open reading frame of 1269 bp and an 831-bp 3' non-coding region with a putative polyadenylation signal 25 bp upstream of a 3' poly(A) tract. The deduced amino acid sequence reveals a putative signal sequence of 30 amino acids followed by a sequence of 393 amino acids that contains eight potential glycosylation sites and a hydrophobic region, which could function as a transmembrane domain. A 60% homology between the known 23 N-terminal amino acid residues of human prostatic acid phosphatase and the N-terminal sequence of lysosomal acid phosphatase suggests an evolutionary link between these two phosphatases. Insertion of the cDNA into the expression vector pSVL yielded a construct that encoded enzymatically active acid phosphatase in transfected monkey COS cells.  相似文献   

13.
De Miranda J  Santoro A  Engelender S  Wolosker H 《Gene》2000,256(1-2):183-188
High levels of D-serine are found in mammalian brain, where it is an endogenous agonist of the strichinine-insensitive site of N-methyl D-aspartate type of glutamate receptors. D-serine is enriched in protoplasmic astrocytes that occur in gray matter areas of the brain and was shown to be synthesized from L-serine. We now report cloning and expression of human serine racemase, an enzyme that catalyses the synthesis of D-serine from L-serine. The enzyme displays a high homology to the murine serine racemase. It contains a pyridoxal 5'-phosphate attachment sequence similar to bacterial biosynthetic threonine dehydratase. Northern-blot analysis show high levels of human serine racemase in areas known to contain large amounts of endogenous D-serine, such as hippocampus and corpus callosum. Robust synthesis of D-serine was detected in cells transfected with human serine racemase, demonstrating the conservation of D-amino acid metabolism in humans. Serine racemase may be a therapeutic target in psychiatric diseases as supplementation of D-serine greatly improves schizophrenia symptoms. We identify the human serine racemase genomic structure and show that the gene encompasses seven exons and localizes to chromosome 17q13.3. Identification of the intron-exon boundaries of the human serine racemase gene will be useful to search for mutations in neuropsychiatric disorders.  相似文献   

14.
Sphingosine-1-phosphate (SPP), the product of sphingosine kinase, is an important signaling molecule with intra- and extracellular functions. The cDNA for the mouse sphingosine kinase has recently been reported. In this paper we describe the cloning, expression and characterization of the human sphingosine kinase (huSPHK1). Sequence analysis comparison revealed that this kinase is evolutionarily very conserved, having a high degree of homology with the murine enzyme, and presenting several conserved regions with bacteria, yeast, plant, and mammalian proteins. Expressed huSPHK1 cDNA specifically phosphorylates D-erythro-sphingosine and, to a lesser extent, D, L-erythro-dihydrosphingosine, and not at all the 'threo' isoforms of dihydrosphingosine; hydroxy-ceramide or non-hydroxy-ceramide; diacylglycerol (DAG); phosphatidylinositol (PI); phosphatidylinositol-4-phosphate (PIP); or phosphatidylinositol-4, 5-bisphosphate (PIP(2)). huSPHK1 shows typical Michaelis-Menten kinetics (V(max)=56microM and K(m)=5microM). The kinase is inhibited by D,L-threo-dihydrosphingosine (K(i)=3microM), and by N, N-dimethyl-sphingosine (K(i)=5microM). Northern blots indicate highest expression in adult lung and spleen, followed by peripheral blood leukocyte, thymus and kidney, respectively. It is also expressed in brain and heart. In addition, database searches with the stSG2854 sequence indicate that huSPHK1 is also expressed in endothelial cells, retinal pigment epithelium, and senescent fibroblasts.  相似文献   

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Human spermidine synthase: cloning and primary structure   总被引:1,自引:0,他引:1  
Using a synthetic deoxyoligonucleotide mixture constructed for a tryptic peptide of the bovine enzyme as a probe, cDNA coding for the full-length subunit of spermidine synthase was isolated from a human decidual cDNA library constructed on phage lambda gt11. After subcloning into the Eco RI site of pBR322 and propagation, both strands of the insert were sequenced using a shotgun strategy. Starting from the first start codon, which was immediately preceded by a GC-rich region including four overlapping CCGCC consensus sequences, an open reading frame for a 302-amino-acid polypeptide was resolved. This peptide had an Mr of 33,827, started with methionine, and ended with serine. The identity of the isolated cDNA was confirmed by comparison of the deduced amino acid sequence with resolved sequences of the tryptic peptides of bovine spermidine synthase. The coding strand of the cDNA revealed no special regulatory or ribosome-binding signals within 82 nucleotides preceding the start codon and no polyadenylation signal within 247 nucleotides following the stop codon. The coding region, containing a 13-nucleotide repeat close to the 5' end, was longer than, and very different from, that of the bacterial counterpart. This region seems to be of retroviral origin and shows marked homology with sequences found in a variety of human, mammalian, avian, and viral genes and mRNAs. By computer analysis, the first 200 nucleotides of the 5' end of the coding strand appear able to form a very stable secondary structure with a free energy change of -157.6 kcal/mole.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

17.
The Chief Medical Officer of Health of the United Kingdom has recommended that the 1990 Human Fertilisation and Embryology Act should be amended to allow cloning in humans for research purposes only. He also recommended that: "The transfer of an embryo created by cell nuclear replacement into the uterus of a woman (so called 'reproductive cloning') should remain a criminal offence" (recommendation 7, Ref. 1). This recommendation implies that nuclear replacement and cloning are the same. They are not. Nuclear transfer constitutes reproductive cloning only when the individual created is genetically identical to the nuclear donor. In this paper, we describe a possible future use of nuclear transfer for the treatment of infertile individuals. The treatment yields an individual that receives approximately equal genetic contributions from each parent. We use this example to illustrate how semantic confusion might lead to plausibly moral and justifiable treatments being legally banned. In doing so, we hope to encourage a more accurate and informed use of language in science, law and politics, so that legislation is properly informed by science and achieves what it intends. BioEssays 23:359-364, 2001.  相似文献   

18.
This paper defends human dignity in two ways. First, by confronting the criticism that human dignity does not serve an important function in contemporary moral discourse and that its function can be sufficiently performed by other moral terms. It is argued that this criticism invites a danger of moral reductionism, which impoverishes moral discourse. The authority of moral philosophy to correct widely shared moral intuitions, rooted in experiences of grave injustices and wrongs, is questioned. Secondly, dignity is defended by showing what is needed to uphold it, both in theory and practice. It is argued, and demonstrated through examples, that human dignity as a universal value ascribed to human beings and the virtue of dignified action are intimately related. This is fleshed out in terms of Kant’s analysis of respect in the practical sense and of virtue as a commitment to the value of dignity as a constitutive end of our moral order. It is furthermore argued that theoretical attempts to ground respect for dignity in human capacities lead to a moral impasse. It is necessary to act as if every human being is worthy of respect. This practical approach requires institutions and specified moral obligations that are integral to the democratic ethos and the rule of law, which guarantees the equal status of human beings. This practical task requires that we consistently tease out and act on the implications of these principles rather than seek deeper justification for the equal worth of humans, articulated in the term human dignity.  相似文献   

19.
Complementary DNA clones coding for the human secreted carbonic anhydrase isozyme (CA VI) have been isolated and their nucleotide sequences determined. These clones identify a 1.45-kb mRNA that is present in high levels in parotid submandibular salivary glands but absent in other tissues such as the sublingual gland, kidney, liver, and prostate gland. Hybridization histochemistry of human salivary glands shows mRNA for CA VI located in the acinar cells of these glands. The cDNA clones encode a protein of 308 amino acids that includes a 17 amino acid leader sequence typical of secreted proteins. The mature protein has 291 amino acids compared to 259 or 260 for the cytoplasmic isozymes, with most of the extra amino acids present as a carboxyl terminal extension. In comparison, sheep CA VI has a 45 amino acid extension [Fernley, R. T., Wright, R. D., & Coghlan, J. P. (1988b) Biochemistry 27, 2815]. Overall the human CA VI protein has a sequence identity of 35% with human CA II, while residues involved in the active site of the enzymes have been conserved. The human sheep secreted carbonic anhydrases have a sequence identity of 72%. This includes the two cysteine residues that are known to be involved in an intramolecular disulfide bond in the sheep CA VI. The enzyme is known to be glycosylated and three potential N-glycosylation sites (Asn-X-Thr/Ser) have been identified. Two of these are known to be glycosylated in sheep CA VI. Southern analysis of human DNA indicates that there is only one gene coding for CA VI.  相似文献   

20.
The primary structure of human C1 inhibitor was determined by peptide and DNA sequencing. The single-chain polypeptide moiety of the intact inhibitor is 478 residues (52,869 Da), accounting for only 51% of the apparent molecular mass of the circulating protein (104,000 Da). The positions of six glucosamine-based and five galactosamine-based oligosaccharides were determined. Another nine threonine residues are probably also glycosylated. Most of the carbohydrate prosthetic groups (probably 17) are located at the amino-terminal end (residues 1-120) of the protein and are particularly concentrated in a region where the tetrapeptide sequence Glx-Pro-Thr-Thr, and variants thereof, is repeated 7 times. No phosphate was detected in C1 inhibitor. Two disulfide bridges connect cysteine-101 to cysteine-406 and cysteine-108 to cysteine-183. Comparison of the amino acid and cDNA sequences indicates that secretion is mediated by a 22-residue signal peptide and that further proteolytic processing does not occur. C1 inhibitor is a member of the large serine protease inhibitor (serpin) gene family. The homology concerns residues 120 through the C-terminus. The sequence was compared with those of nine other serpins, and conserved and nonconserved regions correlated with elements in the tertiary structure of alpha 1-antitrypsin. The C1 inhibitor gene maps to chromosome 11, p11.2-q13. C1 inhibitor genes of patients from four hereditary angioneurotic edema kindreds do not have obvious deletions or rearrangements in the C1 inhibitor locus. A HgiAI DNA polymorphism, identified following the observation of sequence variants, will be useful as a linkage marker in studies of mutant C1 inhibitor genes.  相似文献   

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