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11.
The latest remarkable technological advances in assisted reproduction,
which enable cryopreservation of spermatozoa, embryos and ovarian tissue,
raise difficult and debatable legal, social, ethical and moral issues
concerning the right to posthumous reproduction. Furthermore, reports on
the attitudes of the general public and of centres licensed for infertility
treatment in the United Kingdom found that the majority of women and
centres support the idea of posthumous reproduction. In this paper we
review the data published on this issue, and after considering the various
aspects, we conclude that each case should be discussed and authorized by a
multidisciplinary committee that includes physicians, clergy,
psychiatrists, psychologists, sociologists and other appropriate parties.
In our opinion, the main principles that should guide this committee would
allow posthumous reproduction in the context of marriage when a prior
consent exists. For unmarried persons, post-mortem donation of gametes
should be done only anonymously, if they are in agreement with existing
laws concerning infertility treatments in every country and after
appropriate consent and proper counselling. Moreover, any case which
involves consanguinity or a possibility of incest should be forbidden, both
for ethical and genetic reasons. In a case of pre-existing siblings, they
should be consulted and their informed consent should be granted in advance
so as to avoid legal problems in the inheritance of property.
相似文献
12.
JJ Favre Ph Chaffanjon JG Passagia JP Chirossel 《Surgical and radiologic anatomy : SRA》1995,17(2):133-138
Summary The authors report the results of a series of dissections and anatomic sections of the fronto-basal region of the brain and of the anterior cranial fossa in human cadavers. The constant presence of an arachnoidal cistern above the olfactory nerve was verified. The arachnoid separates from the pial membrane and forms a bridge with the ventral part of the olfactory bulb and tract, from the lateral edge of the olfactory sulcus to the medial edge of the gyrus rectus. The cistern is wide in its anterior portion, between the gyrus rectus and the olfactory bulb, and is reduced to a virtual slit in its posterior portion where the tract is lodged in the olfactory sulcus. The olfactory nerve can be separated without damaging fronto-basal arachnoidial adhesions over several centimeters. Dissection of this region after intravascular injection of colored media shows the constant presence of an artery destined to the olfactory bulb and tract. It originates either from the lateral surface of the anterior cerebral a. (segment A2), or from the medial fronto-basal a., and consistently provides terminal branches in front of the olfactory trigone in the medial olfactory sulcus. At their ventral extremity, the olfactory structures are therefore vascularised independently for several centimeters, from the lower face of the frontal lobe. The independent vascularisation of the olfactory nerve, the tenuous and easily detachable adhesions, and the actual presence of a true arachnoidal cistern all contribute to enabling surgical techniques which conserve olfactory function during anterior approaches.
Vascularisation du nerf olfactif. Rapports méningés et applications chirurgicales
Résumé Les auteurs rapportent les résultats d'une série de dissections et de coupes de la région fronto-basale de l'encéphale et de la fosse crânienne antérieure sur sujets cadavériques. La présence constante d'une citerne arachnoïdienne au dessus du n. olfactif a été vérifiée. L'arachnoïde se sépare du feuillet pial et passe en pont à la partie ventrale du bulbe et du tractus olfactifs, du bord latéral du sillon olfactif au bord médial du gyrus rectus. La citerne est large dans sa portion antérieure, entre le gyrus rectus et le bulbe olfactif, se réduit à une fente virtuelle postérieure lorsque le tractus se loge dans le sillon olfactif. Le n. olfactif peut être séparé sans dommage des adhérences arachnoïdiennes fronto-basales sur quelques centimètres. La dissection de cette région, après injection intravasculaire de masses colorées montre, de façon originale, la présence constante d'une artère destinée au tractus et au bulbe olfactifs. Elle naît soit de la face latérale de l'a. cérébrale antérieure (segment A2), soit de l'a. fronto-basale médiale, pour donner ses branches terminales toujours en avant du trigone olfactif dans le sillon orbitaire médial. Sur quelques centimètres à leur extrémité ventrale, les structures olfactives ont donc une vascularisation indépendante de la face inférieure du lobe frontal. L'indépendance vasculaire du n. olfactif, des adhérences ténues, facilement détachables, et la réalité vérifiée d'une véritable citerne arachnoïdienne permettent d'imaginer des techniques conservatrices de la fonction olfactive utilisées dans plusieurs indications de la chirurgie de la fosse crânienne antérieure.相似文献
13.
R E Martin G P Sackett V M Gunderson B L Goodlin-Jones 《Developmental psychobiology》1988,21(3):251-260
Heart rate (HR) responses evoked by 1 sec of 85-dB white noise were studied in 12 1-year-old pigtailed macaques, 6 of which were raised in social isolation and 6 with mothers and peers. Tests were given for 5 days, with 25 trials each day. Although baseline HR did not differ between groups, the pattern of change from baseline was not the same. Isolates showed only HR acceleration, returning to baseline within 10-11 sec of stimulus onset. Socially reared monkeys had a 10- to 11-sec biphasic response of acceleration followed by deceleration, with subsequent return to baseline. The same group difference in HR pattern occurred when subjects were tested with a less intense 65-dB stimulus. These findings were discussed in terms of activity, emotionality, and autonomic regulatory functions. It was concluded that early rearing experiences may affect later physiological processes involving autonomic nervous system balance. This conclusion was related to observations of persistent individual differences in HR by human children classified as inhibited. 相似文献
14.
Preimplantation genetic diagnosis principles and ethics 总被引:4,自引:0,他引:4
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18.
Background
Genetic polymorphisms of the TCF7L2 gene are strongly associated with large increments in type 2 diabetes risk in different populations worldwide. In this study, we aimed to confirm the effect of the TCF7L2 polymorphism rs7903146 on diabetes risk in a Brazilian population and to assess the use of this genetic marker in improving diabetes risk prediction in the general population. 相似文献19.
Romieu R; Lacabanne V; Kayibanda M; Antoine B; Bennoun M; Chouaib S; Guillet JG; Viguier M 《International immunology》1997,9(10):1405-1413
There is now good evidence that cytokines contribute to the regulation of
tumor growth. The cytokine-driven modulation of tumor growth was
investigated during the progression of a hepatocellular carcinoma (HCC) in
SV40 large T tumor antigen transgenic mice. In vivo, an increased rate of
liver growth correlated with increased transforming growth factor
(TGF)-beta 1 mRNA expression, while the greatest amounts of tumor necrosis
factor (TNF)-alpha mRNA were detected earlier during tumor development.
Conversely, no particular alteration of IL-1 alpha, IL-1 beta, IL-6, IL-2,
IL-4 and IFN-gamma mRNA production could be reported. In vitro,
hepatocyte-like tumor cell lines established at two stages, either before
or after HCC differentiation, were characterized. The early-stage-derived
cell line produced TNF-alpha mRNA, but had barely detectable expression of
TGF-beta 1 mRNA, while later-stage- derived cell lines showed the
reciprocal pattern. All cell lines displayed a lack of sensitivity to
TNF-alpha, although some degree of sensitivity to TNF-alpha could be
observed in the presence of actinomycin-D or after treatment with
IFN-gamma. The early-stage- derived cell line was sensitive to the growth
inhibitory effects of TGF- beta 1, but late-stage-derived tumor cell lines
displayed a loss of sensitivity to TGF-beta 1 which correlated with the
increased expression of TGF-beta 1 mRNA. Altogether, this suggests that
tumor cells contribute to the discrete TNF-alpha and TGF-beta 1 expression
patterns during HCC progression. This model of HCC could be of valuable
interest to assess the impact of various immunotherapeutic strategies on
modulation of tumor growth.
相似文献
20.
Singh DK Griffin DM Pacyniak E Jackson M Werle MJ Wisdom B Sun F Hout DR Pinson DM Gunderson RS Powers MF Wong SW Stephens EB 《Virology》2003,313(2):435-451
The simian-human immunodeficiency virus (SHIV)/ macaque model for human immunodeficiency virus type 1 has become a useful tool to assess the role of Vpu in lentivirus pathogenesis. In this report, we have mutated the two phosphorylated serine residues of the HIV-1 Vpu to glycine residues and have reconstructed a SHIV expressing this nonphosphorylated Vpu (SHIV(S52,56G)). Expression studies revealed that this protein was localized to the same intracellular compartment as wild-type Vpu. To determine if this virus was pathogenic, four pig-tailed macaques were inoculated with SHIV(S52,56G) and virus burdens and circulating CD4(+) T cells monitored up to 1 year. Our results indicate that SHIV(S52,56G) caused rapid loss in the circulating CD4(+) T cells within 3 weeks of inoculation in one macaque (CC8X), while the other three macaques developed no or gradual numbers of CD4(+) T cells and a wasting syndrome. Histological examination of tissues revealed that macaque CC8X had lesions in lymphoid tissues (spleen, lymph nodes, and thymus) that were typical for macaques inoculated with pathogenic parental SHIV(KU-1bMC33) and had no lesions within the CNS. To rule out that macaque CC8X had selected for a virus in which there was reversion of the glycine residues at positions 52 and 56 to serine residues and/or compensating mutations occurred in other genes associated with CD4 down-regulation, sequence analysis was performed on amplified vpu sequences isolated from PBMC and from several lymphoid tissues at necropsy. Sequence analysis revealed a reversion of the glycine residues back to serine residues in this macaque. The other macaques maintained low virus burdens, with one macaque (P003) developing a wasting syndrome between months 9 and 11. Histological examination of tissues from this macaque revealed a thymus with severe atrophy that was similar to that of a previously reported macaque inoculated with a SHIV lacking vpu (Virology 293, 2002, 252). Sequence analysis revealed no reversion of the glycine residues in the vpu sequences isolated from this macaque. These results contrast with those from four macaques inoculated with the parental pathogenic SHIV(KU-1bMC33), all of which developed severe CD4(+) T cell loss within 1 month after inoculation. Taken together, these results indicate that casein kinase II phosphorylation sites of Vpu contributes to the pathogenicity of the SHIV(KU-1bMC33) and suggest that the SHIV(KU-1bMC33)/pig-tailed macaque model will be useful in analyzing amino acids/domains of Vpu that contribute to the pathogenesis of HIV-1. 相似文献