84 research outputs found
Increase of mitochondrial DNA content and transcripts in early bovine embryogenesis associated with upregulation of mtTFA and NRF1 transcription factors
BACKGROUND: Recent work has shown that mitochondrial biogenesis and mitochondrial functions are critical determinants of embryonic development. However, the expression of the factors controlling mitochondrial biogenesis in early embryogenesis has received little attention so far. METHODS: We used real-time quantitative PCR to quantify mitochondrial DNA (mtDNA) in bovine oocytes and in various stages of in vitro produced embryos. To investigate the molecular mechanisms responsible for the replication and the transcriptional activation of mtDNA, we quantified the mRNA corresponding to the mtDNA-encoded cytochrome oxidase 1 (COX1), and two nuclear-encoded factors, i.e. the Nuclear Respiratory Factor 1 (NRF1), and the nuclear-encoded Mitochondrial Transcription Factor A (mtTFA). RESULTS: Unlike findings reported in mouse embryos, the mtDNA content was not constant during early bovine embryogenesis. We found a sharp, 60% decrease in mtDNA content between the 2-cell and the 4/8-cell stages. COX1 mRNA was constant until the morula stage after which it increased dramatically. mtTFA mRNA was undetectable in oocytes and remained so until the 8/16-cell stage; it began to appear only at the morula stage, suggesting de novo synthesis. In contrast, NRF1 mRNA was detectable in oocytes and the quantity remained constant until the morula stage. CONCLUSION: Our results revealed a reduction of mtDNA content in early bovine embryos suggesting an active process of mitochondrial DNA degradation. In addition, de novo mtTFA expression associated with mitochondrial biogenesis activation and high levels of NRF1 mRNA from the oocyte stage onwards argue for the essential function of these factors during the first steps of bovine embryogenesis
Le monoï de Tahiti, véritable matière première cosmétique multi-usage (de sa fabrication traditionnelle à la production industrielle )
AIX-MARSEILLE2-BU Pharmacie (130552105) / SudocPARIS-BIUP (751062107) / SudocSudocFranceF
Structure and Chromosomal Distribution of Human Mitochondrial Pseudogenes
International audienc
Mitochondries et reproduction
Les mitochondries jouent un rôle central dans le métabolisme énergétique cellulaire. Une de leurs particularités est de posséder leur propre génome, dont la transmission est exclusivement maternelle. Leur implication dans la reproduction humaine est une notion relativement récente qui suscite un intérêt scientifique et médical croissant. Elles peuvent influencer la qualité des ovocytes et des spermatozoïdes, mais aussi la fécondation et le développement embryonnaire. De nouvelles techniques thérapeutiques telles que le transfert de cytoplasme ovocytaire compromettent fortement la transmission uniparentale de l’ADN mitochondrial et soulèvent d’importantes questions éthiques. Cet article tente de faire le point sur les acquisitions récentes concernant le rôle des mitochondries dans la fertilité et la reproduction humaines.Mitochondria play a primary role in cellular energetic metabolism. They possess their own DNA, which is exclusively maternally transmitted. The relatively recent idea that mitochondria may be directly involved in human reproduction is arousing increasing interest in the scientific and medical community. It has been shown that the functional status of mitochondria contributes to the quality of oocytes and spermatozoa, and plays a part in the process of fertilisation and embryo development. Moreover, new techniques, such as ooplasm transfer, compromise the uniquely maternal inheritance of mitochondrial DNA, raising important ethical questions. This review discusses recent information about mitochondria in the field of human fertility and reproduction
Franco-chinese dossier: regulations on plant-based medical products in France and China
AbstractFollowing the cooperation agreement in the field of medicine and health between the government of the French Republic and the government of the People's Republic of China, a « Franco-chinese Herbal Group » has been set up.The objective of this group is to establish a list of medicinal plants from the traditional Chinese Pharmacopoeia, which could be proposed to the French Health Products Agency with a view to include them eventually in the French Pharmacopoeia and in the Agency's list of plants (Instructions Booklet N° 3).The group is made up of pharmacological, galenical, toxicological and clinical experts from both parties. It officially meets twice a year. Plants proposed must comply with quality and safety criteria required for herbal medicinal products in France. Traditionnal usage must be acknowledged.The development of herbal medicinal products is difficult in Europe because differents reglementary rules exist in the differents european member states. The basis of harmonisation should be established on the assessment of quality objectives and using safety and efficacy data already available. Don't give a legal status to herbal medicine provide abuses and accidents
6 Franzosiche Künstler Heute : Jean-Baptiste Audat, Francis Bugarin, Serge Fauchier, Dominique Gauthier, Anne-Marie Pécheur, Yves Reynier = 6 peintres français aujourd'hui : Jean-Baptiste Audat, Francis Bugarin, Serge Fauchier, Dominique Gauthier, Anne-Marie Pécheur, Yves Reynier
MRI/TRUS data fusion for prostate brachytherapy. Preliminary results.
International audienceProstate brachytherapy involves implanting radioactive seeds (I125 for instance) permanently in the gland for the treatment of localized prostate cancers, e.g., cT1c-T2a N0 M0 with good prognostic factors. Treatment planning and seed implanting are most often based on the intensive use of transrectal ultrasound (TRUS) imaging. This is not easy because prostate visualization is difficult in this imaging modality particularly as regards the apex of the gland and from an intra- and interobserver variability standpoint. Radioactive seeds are implanted inside open interventional MR machines in some centers. Since MRI was shown to be sensitive and specific for prostate imaging whilst open MR is prohibitive for most centers and makes surgical procedures very complex, this work suggests bringing the MR virtually in the operating room with MRI/TRUS data fusion. This involves providing the physician with bi-modality images (TRUS plus MRI) intended to improve treatment planning from the data registration stage. The paper describes the method developed and implemented in the PROCUR system. Results are reported for a phantom and first series of patients. Phantom experiments helped characterize the accuracy of the process. Patient experiments have shown that using MRI data linked with TRUS data improves TRUS image segmentation especially regarding the apex and base of the prostate. This may significantly modify prostate volume definition and have an impact on treatment planning
MRI/TRUS data fusion for prostate brachytherapy. Preliminary results.
International audienceProstate brachytherapy involves implanting radioactive seeds (I125 for instance) permanently in the gland for the treatment of localized prostate cancers, e.g., cT1c-T2a N0 M0 with good prognostic factors. Treatment planning and seed implanting are most often based on the intensive use of transrectal ultrasound (TRUS) imaging. This is not easy because prostate visualization is difficult in this imaging modality particularly as regards the apex of the gland and from an intra- and interobserver variability standpoint. Radioactive seeds are implanted inside open interventional MR machines in some centers. Since MRI was shown to be sensitive and specific for prostate imaging whilst open MR is prohibitive for most centers and makes surgical procedures very complex, this work suggests bringing the MR virtually in the operating room with MRI/TRUS data fusion. This involves providing the physician with bi-modality images (TRUS plus MRI) intended to improve treatment planning from the data registration stage. The paper describes the method developed and implemented in the PROCUR system. Results are reported for a phantom and first series of patients. Phantom experiments helped characterize the accuracy of the process. Patient experiments have shown that using MRI data linked with TRUS data improves TRUS image segmentation especially regarding the apex and base of the prostate. This may significantly modify prostate volume definition and have an impact on treatment planning
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