Legal Implications of Sterilization

Sexual sterilization is legal when it is an integral part of a procedure for the preservation of the life or health of a patient. Done for other reasons it may not be illegal, but this has not been tested in Canadian courts. It is, broadly speaking, a surgical procedure; it is commonly, but not always, successful; complications, while rare, do occur; the results tend to be irreversible. The same end, the prevention of pregnancy, may be attained by other methods which are safer, less liable to complications, less permanent and so should be used unless contraindicated. Patients'' statements that they do not like contraceptives should not be accepted as a reason for sterilization. Sexual sterilization should be reserved for those occasions when it is necessary for the preservation of the health or life of the individual who is to be sterilized.     

Uptake of sorbitol by chick embryo heart cells at various stages of development.

Sorbitol enters chick embryo heart cells from five days of development on. The rate of sorbitol entry becomes slower as development proceeds and the data suggest this is principally due to an increase in the apparent Km of transport, the Vmax remaining relatively constant. The uptake of sorbitol displays saturation kinetics and is believed on this ground to be carrier-mediated. Sorbitol does not appear to be actively transported since it is not concentrated against a gradient and its uptake is not inhibited by iodoacetate or 2, 4-dinitrophenol. Sorbitol does not appear to be taken up via the glucose transport system since uptake is not stimulated by insulin or inhibited by glucose or phloretin.     

Eugenic Selection Benefits Embryos

The primary question to be addressed here is whether pre‐implantation genetic diagnosis (PGD), used for both negative and positive trait selection, benefits potential supernumerary embryos. The phrase ‘potential supernumerary embryos’ is used to indicate that PGD is typically performed on a set of embryos, only some of which will be implanted. Prior to any testing, each embryo in the set is potentially supernumerary in the sense that it may not be selected for implantation. Those embryos that are not selected, and hence destroyed or frozen, are ‘actually supernumerary’. The argument to be advanced is hypothetical: If embryos may be said to benefit or be harmed by our actions, then PGD used to select for an embryo or embryos with the highest expected Wellbeing benefits potential supernumerary embryos. The argument shows that the ‘non‐identity’ problem is not sufficient to show that eugenic selection does not benefit supernumerary embryos.     

Pyruvate dehydrogenase complex from higher plant mitochondria and proplastids: regulation

The activity of the pyruvate dehydrogenase complex from pea (Pisum sativum L.) mitochondria is inhibited when MgATP is added to the reaction mixture; 50% inhibition occurs at 4 mm ATP. The inhibition does not increase with time and is higher in the more highly purified preparations. Crude preparations of the complex show a time-dependent inactivation when incubated with 7.5 mm MgATP alone but this is not found with the more highly purified complex. This inactivation does not occur at 0 C. The complex could not be reactivated by high concentrations of Mg(2+). It is suggested that a phosphorylation-dephosphorylation mechanism may occur in plants, but the phosphatase and kinase are not tightly bound to the complex and are lost on isolation. The complex does not respond in a significant manner to energy charge. The NAD(+) to NADH ratio is the principal means of regulation of the complex, NADH being competitive with NAD(+) for the dihydrolipoamide component. The CoA to acetyl-CoA ratio is not important in regulation.The castor bean (Ricinus communis L.) proplastid complex is inhibited by the addition of 2 mm MgATP to the assay mixture. The inhibition is immediate, suggesting that phosphorylation of the enzyme is not involved or must be very rapid. Incubation of the complex with 20 mm MgCl(2) causes an activation of the complex. Maximum activity is not expressed in this case for 30 minutes. A similar activation can be achieved by preincubating the complex with 1 mm pyruvate. These data suggest that the complex is not fully activated on isolation.     

UNREQUESTED TERMINATION OF LIFE: IS IT PERMISSIBLE?

Conclusion: One can appreciate and understand why doctors take action to terminate life without being requested by the patient who is suffering unbearably and pointlessly. But in my opinion such action is not permissible from a moral point of view. In the first place there is a danger that interests other than those of the patient will play a decisive role. Furthermore, it is not permissible because the interest of society as a whole is at stake. The safety of all future patients would no longer be guaranteed. It is also not allowed because the medical profession must constantly be on its guard so that it does not become caught up in the situations described above. In nearly every case it should be possible for doctor and patient to discuss the termination of life explicitly and at an early stage. The ultimate reason why termination of life without request of the patient is not permissible is that in principle it will never be possible to draw a clear dividing line between unrequested and unwanted termination of life. However, it is conceivable that in certain cases the conflict of loyalties will be such that unrequested termination of life is justified. In the rare extreme case of an inescapable conflict of equally stringent duties, it may just be necessary to do something which in essence is impermissible.     

The Social Value Requirement Reconsidered

It is widely assumed that it is ethical to conduct research with human subjects only if the research has social value. There are two standard arguments for this view. The allocation argument claims that public funds should not be devoted to research that lacks social value. The exploitation avoidance argument claims that subjects are exploited if research has no social value. The primary purpose of this article is to argue that these arguments do not succeed. The allocation argument has little relevance to commercial research. Social value is not necessary to avoid exploitation if subjects benefit from participation. Although the standard arguments for a social value requirement do not succeed, that view might be justified in a different way. It might be justified by appeal to the importance of social trust or the integrity of physician investigators. It is possible but doubtful that these arguments succeed.     

TEMPORARY LOCALIZED DEPRESSION OF TRITIATED THYMIDINE INCORPORATION IN MOUSE TISSUES AFTER PULSE LABELLING

Approximately two to six in every 100 mice injected with ³H-TdR appear not to incorporate the labelled precursor into the DNA. The tritium activity appears to be distributed throughout these poor utilizers of thymidine. The lack of incorporation of the precursor is not always general to the whole animal but may be restricted to a given tissue. The effect does not appear to be permanent but varies with time.     

Recursive evolution.

In evolutionary systems in which the units (individuals) are generated by a morphogenetic process, unbiased "mosaic type" mutability of the phenotype is not possible (Waddington's principle). The question is whether this unavoidable "channeling" can itself be made plastic through provision of alternative morphogeneses possessing differing "hot spots." If so, plasticity would not only be reestablished, but be established at a higher level. Plasticity itself would be plastic. The property of ultrasplasticity is evolutionarily necessary and stable, but perhaps not possible. Ultraplastic systems form a subclass of "temporal brains" as described in deductive biology. Many of their properties have yet to be discovered.     

Cost Containment: An Economist's View

Rising medical care costs are not the problem they seem to be, in part because quality of care is not considered. The problem may be more the absence of choice of alternative health benefit packages with price differences. The future of health services in the United States will have more competing alternatives requiring physicians to be more cost conscious.     

Unconventional bed mates: Gaia and the selfish gene

In this forum, David M. Wilkinson argued that Gaia-type phenomena can be explained by conventional ecological ideas meaning that such phenomena do not require major changes to existing ecological or evolutionary theory. Overstating my case a little, I will argue that a reconciliation between Gaia and Darwinism will not be conventional in the sense of mainstream ecology. The main addition of this essay is an exploration in how far the claim that the atmosphere is an extension of life on Earth is logically correct. In a thought experiment, the idea of extended phenotypes by Richard Dawkins can be integrated with the one of Gaia. The problem of cheats remains pertinent, however, because the atmosphere will not select differentially between cheats and non-cheats. Conclusion: Gaia-type phenomena will be by-products of naturally selected traits. As such they are not jeopardised by cheats, because side effects can be free to self-organise, while the main effects will be naturally selected for evolutionarily stable states. Understanding the laws of self-organisation of such side effects will be of major importance to all environmental sciences.     

Not across the North Pole: plant migration in the Arctic

? The vascular plant flora of 66 arctic islands was studied to determine whether the islands have been occupied by random long-distance dispersal (LDD) or in a highly structured northward migration pattern via intervening islands as stepping-stones. ? A maximum parsimonious migration model minimizing dispersal distances of 1256 vascular plant taxa was calculated in the framework of network analysis. ? Plant dispersal is not stochastic in the Arctic at the global scale. Inferred mean dispersal distances of the plants occurring on arctic islands are c. 580 km (median 460 km). A LDD across the North Pole could not be inferred in the model and species may be recruited mainly from the nearest mainland or islands. At smaller scales, among adjacent islands, dispersal of vascular plants may be incomplete. Arctic islands do not yet appearto be saturated with species. ? The results suggest that changes in biodiversity in Arctic islands can be more easily predicted at the global scale than at the local scale. Because islands are not yet saturated with species, new colonizations may not necessarily be linked to climate change.     

Reason for indispensability of threonine in humans and other mammals in comparative aspect

The essential amino acid threonine is not synthesized in vertebrates, so it must be obtained from food. During evolution, the decomposition of threonine has changed. Because the decomposition of threonine catalyzed by threonine dehydratase is irreversible, in the present work attention is focused on threonine dehydrogenase to show the inability of this enzyme to synthesize threonine in a reaction that would be the reverse of the reaction of threonine decomposition. The reason why threonine dehydrogenase cannot be used for the biosynthesis of threonine in mammalian tissues is discussed. It is concluded that some quantity of threonine is involved in transamination.     

Copper and Manganese Concentrations in Biliary Cirrhosis of Liver

The presence of large amounts of copper in the liver in primary biliary cirrhosis has been confirmed; a similar increase is not found in cases of long-standing extrahepatic biliary obstruction. The serum caeruloplasmin levels are raised in primary and secondary biliary cirrhosis, but this increase does not appear to be related to the degree of increase of hepatic copper. The manganese content of the liver is slightly raised in both these conditions.The reason for the increased metal content in these circumstances cannot yet be determined, and the effects are not yet understood.     

Inhibition of peptide initiation by a low molecular weight RNA from rabbit reticulocytes

A heat-stable inhibitor of protein synthesis has been isolated from the postribosomal supernatant of rabbit reticulocytes. Its activity is not susceptible to protease treatment but is destroyed by incubation with alkali. Inhibitory activity can be quantitatively recovered in the aqueous phase after phenol extraction and has the ultraviolet absorption spectrum of a nucleic acid. It is concluded that the inhibitor is RNA. The inhibitory activity sediments in the range of 3 S, but it has not been demonstrated whether the inhibitor RNA is a single molecular species. The inhibitory RNA does not affect peptide elongation but rather blocks a step of peptide initiation. It does not interfere with the formation of the ternary complex between initiation factor 2, GTP, and methionyl-tRNAMetf and does not activate a protein kinase phosphorylating initiation factor 2. The inhibitory RNA appears to be a novel type of RNA that inhibits polypeptide initiation at a step involving ribosomal subunits.     

Repair of intrinsic DNA lesions.

The repair of apurinic/apyrimidinic (AP) sites is described. The major pathway involves hydrolysis of the stable phosphodiester bond on the 5' side of the lesion by an AP endonuclease. The 5' terminal deoxyribose-phosphate residue is excised by a separate phosphodiesterase which does not appear to be an exonuclease. Repair replication of the single missing nucleotide residue by a DNA polymerase and ligation complete the excision-repair process. The possibility that minor DNA lesions may accumulate with time in long-lived cells is considered. Such lesions should be chemically stable and should not be recognized by DNA-repair enzymes.     

Gravimorphism in Trees: 2. The Effect of Gravity on Bud-break in Osier Willow

Inclination of shoots of osier willow (Salix viminalis) fromthe vertical position results in outgrowth of buds on the upperside, whereas those on the lower side remain inactive. Thiseffect was shown to be caused by gravity, and not by light ormechanical strain. The effect of gravity is not mediated throughfactors translocated from the roots or from the apical regions.The buds on the lower side are apparently not inhibited by thoseon the upper side of the shoot. Gravity-mediated lateral transportof auxin from the upper to the lower half of the stem is nota controlling factor, but such transport within each half ofthe stem may be important. The angle subtended by the bud itselfto the direction of gravity is not an important factor. Bud-breakis thought to be controlled by a mechanism acting between thebud and the adjacent tissues and which is affected by the orientationof the bud and the adjacent tissues relative to gravity.     

Demonstration of the existence of a second,non-lysosomal glucocerebrosidase that is not deficient in Gaucher disease

In addition to the lysosomal glucocerebrosidase, a distinct β-glucosidase that is also active towards glucosylceramide could be demonstrated in various human tissues and cell types. Subcellular fractionation analysis revealed that the hitherto undescribed glucocerebrosidase is not located in lysosomes but in compartments with a considerably lower density. The non-lysosomal glucocerebrosidase differed in several respects from lysosomal glucocerebrosidase. The non-lysosomal isoenzyme proved to be tightly membrane-bound, whereas lysosomal glucocerebrosidase is weakly membrane-associated. The pH optimum of the non-lysosomal isoenzyme is less acidic than that of lysosomal glucocerebrosidase. Non-lysosomal glucocerebrosidase, in contrast to the lysosomal isoenzyme, was not inhibited by low concentrations of conduritol B-epoxide, was markedly inhibited by taurocholate, was not stimulated in activity by the lysosomal activator protein saposin C, and was not deficient in patients with Gaucher disease. Non-lysosomal glucocerebrosidase proved to be less sensitive to inhibition by castanospermine or deoxynojirimycin but more sensitive to inhibition by D-gluconolactone than the lysosomal glucocerebrosidase. The physiological function of this second, non-lysosomal, glucocerebrosidase is as yet unknown.     

Histidine-Mediated Control of Tryptophan Biosynthetic Enzymes in Neurospora crassa

The formation of the five tryptophan biosynthetic enzymes of Neurospora crassa was shown to be derepressed in histidine-starved cells. This histidine-mediated derepression was not due to a lowered intracellular concentration of tryptophan in these cells. Furthermore, histidine-mediated derepression of tryptophan enzymes was found to be coordinate and not subject to reversal by tryptophan of either exogenous or biosynthetic origin. The synthesis of tryptophan enzymes also was found to be coordinate in cells which were not histidine-starved. Although histidine is clearly involved in regulating the synthesis of tryptophan enzymes, it did not prevent either tryptophan-mediated derepression of tryptophan enzymes or indole-3-glycerol phosphate-mediated derepression of tryptophan synthetase.     

利用SRY基因和微卫星标记鉴定反刍动物性别

以反刍动物为研究对象,应用多重PCR技术扩增绵羊基因组中X、Y染色体上的4个微卫星标记和SRY基因, 根据基因型进行性别鉴定,试图通过一次DNA扩增同时提供性别鉴定和基因分型的信息。结果表明所设计SRY基因的引物具有高度特异性,是性别鉴定的主要依据,而Y染色体上的MCM158、MAF45两标记由于特异性不好,因此不适用于性别鉴定,对于X染色体上所选的两标记MILVET09和AE25只能进一步验证所鉴定的雄性个体。得出结论在被检个体中,能同时扩增出SRY基因、MCM158、MAF45,X染色体上MILVET09和AE25,且X染色体上的MILVET09、AE25基因型为纯合子的个体为正常的雄性;被检个体中只有Y染色体上MCM158、MAF45和X染色体上MILVET09、AE25的扩增产物,而没有SRY基因的扩增产物,则被检个体为雌性,且MILVET09、AE25的基因型对雌性个体的性别判断无影响。MCM158、MAF45两标记基因型不影响个体的性别鉴定结果。
     

Genetic therapy, person-regarding reasons and the determination of identity -- a reply to Robert Elliot

I have outlined two ways of defending the claim that there are so-called person-regarding reasons for practising gene therapy on human conceptuses. One is metaphysical and concerns our nature and identity. The upshot of it is that, in cases of most interest, this therapy does not affect our identity, by bringing into existence anyone of our kind who would not otherwise have existed. The other defence is value theoretical and claims that even if genetic therapy were to affect the identity of beings our kind, there could still be person-regarding reasons for performing it, since we can be benefited and harmed by being caused to exist or not to exist. Robert Elliot has attacked both of these lines, and my present objective is to show how his criticisms can be deflected.