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van Muiswinkel FL de Vos RA Bol JG Andringa G Jansen Steur EN Ross D Siegel D Drukarch B 《Neurobiology of aging》2004,25(9):1253-1262
Dopamine (DA) autooxidation, and consequent formation of neurotoxic DA-derived quinones and reactive oxygen species, has been implicated in dopaminergic cell death and, hence, in the pathogenesis of Parkinson's disease (PD). Stimulation of pathways involved in the detoxication of DA-quinones in the brain is hypothesized to be an effective means to limit oxidative stress and to confer neuroprotection in PD. In this respect, the inducible flavoprotein NAD(P)H:quinone oxidoreductase (NQO1) is of particular interest as it is directly implicated in the detoxication of DA-quinones and, in addition, has broad spectrum anti-oxidant properties. To study the potential pathophysiological role of NQO1 in PD, the cellular expression of NQO1 was examined in the mesencephalon of PD patients and age-matched controls. In the substantia nigra pars compacta (SNpc), NQO1 was found to be expressed in astroglial and endothelial cells and, albeit less frequently, also in dopaminergic neurons. Moreover, while overt NQO1 immunoreactivity was absent in the surrounding nervous tissue, in the Parkinsonian SNpc a marked increase in the astroglial and neuronal expression of NQO1 was consistently observed. 相似文献
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The effects of co-culture with human fibroblasts on human embryo development in vitro and implantation 总被引:5,自引:0,他引:5
Wetzels AM; Bastiaans BA; Hendriks JC; Goverde HJ; Punt-van der Zalm AP; Verbeet JG; Braat DD 《Human reproduction (Oxford, England)》1998,13(5):1325-1330
In a human in-vitro fertilization (IVF) programme, the effect of co-
culture of embryos with human fibroblasts was evaluated with respect to
pregnancy rate and embryo development. Patients were included in the study
after giving informed written consent. The IVF treatments were randomly
assigned by stratification of both age (<36 versus > or =36 years)
and previous IVF attempts (yes versus no). After fertilization was
established, the zygotes were transferred to a 4-well dish with or without
fibroblasts and cultured for 2 days. On the third day after ovum pick-up
(OPU), cell number and quality [5 (good) to 1 (poor)] of the embryos were
scored and a maximum of three embryos was transferred. Supernumerary
embryos of good quality were cryopreserved. The design of this study was a
group sequential trial with the objective of detecting differences between
pregnancy rates following IVF with conventional incubation or incubation in
co-culture with fibroblasts. This design included one evaluation at
half-way data collection. In the study, 148 patients had an OPU, of whom 77
were allocated to the co-culture group. There was no statistically
significant difference in pregnancy rate, cell number and embryo quality
between the two groups. The ongoing pregnancy rate per embryo transfer was
27% in co-culture and 30% in the conventional culture group. The
implantation rates per transferred embryo were 17 and 18% respectively.
Using a multivariate logistic regression model for the probability of
ongoing pregnancies, the odds ratio of co-culture, adjusted for age and
previous IVF attempts, was not statistically significant. In conclusion,
co-culture with human fibroblasts does not contribute to an improvement of
embryo quality nor to a higher pregnancy rate after IVF in an unselected
group of patients.
相似文献
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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