Generation of an induced pluripotent stem cell line from a patient with hereditary multiple endocrine neoplasia 2B (MEN2B) syndrome with "highest risk" RET mutation.

Multiple Endocrine Neoplasia Type 2B (MEN2B) is a cancer-predisposing syndrome that affects patients with germline RET mutations. The clinical spectrum of the syndrome includes medullary thyroid carcinoma (MTC) and pheochromocytoma. Currently, there is no satisfactory model recapitulating all the features of the disease especially at the level of stem cells. We generated induced pluripotent stem cells (iPSCs) from a patient with RET mutation at codon 918 who developed pheochromocytoma and MTC. These iPSC had normal karyotype, harboured the RETM918T mutation and expressed pluripotency hallmarks. A comprehensive pathological assessment of teratoma was performed after injection in immunodeficient mice.

Generation of an induced pluripotent stem cell line from a patient with chronic myeloid leukemia (CML) resistant to targeted therapies.

Chronic myeloid leukemia (CML) is a clonal malignancy initiated by the occurrence of a t (9;22) translocation, generating Ph1 chromosome and BCR-ABL oncogene in a primitive hematopoietic stem cell (HSC). The resistance of HSC to targeted therapies using tyrosine kinase inhibitors remains a major obstacle towards the cure. We have generated an iPSC line from a patient with CML using leukemic CD34+ cells cryopreserved at diagnosis. Ph1+ CML cells were reprogrammed by non-integrative viral transduction. These iPSCs harboured Ph1 chromosome and expressed pluripotency hallmarks as well as BCR-ABL. Teratoma assays revealed normal differentiation after injection in immunodeficient mice.

Generation of an induced pluripotent stem cell line from a patient with hereditary multiple endocrine neoplasia 2A (MEN2A) syndrome with RET mutation.

Multiple Endocrine Neoplasia Type 2A (MEN2A) is a cancer-predisposing syndrome that affects patients with germline RET mutations. The clinical spectrum of the syndrome includes medullary thyroid carcinoma (MTC), pheochromocytoma, hyperparathyroidism and cutaneous lichen amyloidosis (CLA) and/or Hirschsprung disease in some variants. Currently, there is no satisfactory animal model recapitulating all the features of the disease especially at the level of stem cells. We generated induced pluripotent stem cells (iPSCs) from a patient with RET mutation at codon 634 who developed pheochromocytoma and MTC. RETC634Y-mutated cells were reprogrammed by non-integrative viral transduction. These iPSCs had normal karyotype, harboured the RETC634Y mutation and expressed pluripotency hallmarks as well as RET. A comprehensive pathological assessment of teratoma was performed after injection in immunodeficient mice.

Characterization of human PGD blastocysts with unbalanced chromosomal translocations and human embryonic stem cell line derivation?

Novel embryonic stem cell lines derived from embryos carrying structural chromosomal abnormalities obtained after preimplantation genetic diagnosis (PGD) are of interest to study in terms of the influence of abnormalities on further development. A total of 22 unbalanced blastocysts obtained after PGD were analysed for structural chromosomal defects. Morphological description and chromosomal status of these blastocysts was established and they were used to derive human embryonic stem cell (ESC) lines. An outgrowth of cells was observed for six blastocysts (6/22; 27%). For two blastocysts, the exact morphology was unknown since they were at early stage, and for four blastocysts, the inner cell mass was clearly visible. Fifteen blastocysts carried an unbalanced chromosomal defect linked to a reciprocal translocation, resulting in a positive outgrowth of cells for five blastocysts. One human ESC line was obtained from a blastocyst carrying a partial chromosome-21 monosomy and a partial chromosome-1 trisomy. Six blastocysts carried an unbalanced chromosomal defect linked to a Robertsonian translocation, and one showed a positive outgrowth of cells. One blastocyst carried an unbalanced chromosomal defect linked to an insertion and no outgrowth was observed. The efficiency of deriving human ESC lines with constitutional chromosomal disorders was low and probably depends on the initial morphological aspect of the blastocysts and/or the type of the chromosomal disorders.

Bcl2, a transcriptional target of p38alpha, is critical for neuronal commitment of mouse embryonic stem cells.

Mouse embryonic stem (ES) cells remain pluripotent in vitro when grown in the presence of leukemia inhibitory factor (LIF) cytokine. LIF starvation leads to cell commitment, and part of the ES-derived differentiated cells die by apoptosis together with caspase3-cleavage and p38alpha activation. Inhibition of p38 activity by chemical compounds (PD169316 and SB203580), along with LIF withdrawal, leads to different outcomes on cell apoptosis, giving the opportunity to study the influence of apoptosis on cell differentiation. By gene profiling studies on ES-derived differentiated cells treated or not with these inhibitors, we have characterized the common and specific set of genes modulated by each inhibitor. We have also identified key genes that might account for their different survival effects. In addition, we have demonstrated that some genes, similarly regulated by both inhibitors (upregulated as Bcl2, Id2, Cd24a or downregulated as Nodal), are bona fide p38alpha targets involved in neurogenesis and found a correlation with their expression profiles and the onset of neuronal differentiation triggered upon retinoic acid treatment. We also showed, in an embryoid body differentiation protocol, that overexpression of EGFP (enhanced green fluorescent protein)-BCL2 fusion protein and repression of p38alpha are essential to increase formation of TUJ1-positive neuronal cell networks along with an increase in Map2-expressing cells.

[Forceps: description, obstetric mecanics, indications and contra-indications]. / Forceps : description, mécanique, indications et contre-indications.

Obstetric forceps are used to guide fetal movement during delivery, ideally accompanied by active pushing by the mother. Forceps in the form of "tongs" appeared in the 17(th) century, and by the 19(th) century had evolved into forceps with two crossing shafts (Levret, Pajot, Kielland), axis-traction forceps (Tarnier), and forceps with convergent shafts (Démelin, Suzor). Application and traction differ according to the type of instrument, and require extensive training and knowledge of obstetric mechanics. The easiest and most suitable applications are anterior. In transverse application, forceps with convergent shafts or another instrument (spatulas or vacuum extractor) are to be preferred. Certain deliveries can be difficult, and require careful evaluation informed by experience. If the fetus is not progressing after three pulls, this route of delivery should be abandoned.

Uterine compression sutures for postpartum bleeding with uterine atony.

OBJECTIVE: To assess the efficacy of a new uterine compression suturing technique in reducing postpartum haemorrhage secondary to severe uterine atony. DESIGN: Retrospective study. SETTING: University hospital between December 2000 and March 2006. POPULATION: Twenty women with uterine atony and postpartum bleeding that did not react to usual medical management. METHODS: All these women underwent compression suturing of the uterus, in which the anterior and posterior walls of the uterus were attached so as to compress the uterus. MAIN OUTCOME MEASURES: Arrest of the bleeding, complications and fertility. RESULTS: Uterine compression suturing was sufficient to stop the bleeding immediately in 95% of the women. None of the women developed complications related to the procedure. All the women recovered normal menstrual cycles. Since uterine compression suturing, eight women have tried to conceive and six (75%) have had a term delivery. CONCLUSION: Uterine compression suturing is a simple conservative procedure to stop postpartum haemorrhage in the case of failure of the usual management. This surgical technique can be performed quickly and does not seem to decrease fertility.

[Atypical lipomatous tumour of the vulva. About one case]. / Tumeur adipeuse atypique de la vulve. A propos d'un cas.

Liposarcoma of the vulva is a rare entity. This unusual localization with atypical clinical and histological appearance may induce diagnostic and treatment delay. We report the 13th case shown in the literature in a 31-year-old woman initially treated for a vulvar lipoma. Arguments based on clinical short term recurrence, histological infiltrating adipocytes, and cytogenentical findings evoked well-differentiated liposarcoma. Even though cytogenetic abnormalities, involving MDM2 and CDK4 genes, have been found, a certainty in malignity diagnosis could be difficult. In these cases, treatment decision may be uneasy. This case report recalls difficulties encountered in uterine hypercellular leiomyomas.

Murine embryonic stem cell in vitro differentiation: applications to the study of vascular development.

The present review summarizes knowledge accumulated during the last decade concerning in vitro endothelial differentiation from embryonic stem (ES) cells. There is now growing evidence that ES cells may provide a powerful model system to determine the cellular and molecular mechanisms of vascular development. ES cells differentiate into the endothelial lineage by successive maturation steps recapitulating in vivo events observed in the embryo. Further maturation of ES-derived embryoid bodies either in three dimensional gels or in confrontation cultures with tumor spheroids can also provide a model of physiological or tumoral angiogenesis. The data obtained from experimental in vitro differentiation of genetically modified mouse ES cells highlight the potential and the complementarity of this model system to in vivo gene knock out studies. We also consider and discuss some of the potential applications of ES cell technology in vascular biology for future directions in basic research and medicine, by manipulation of differentiation and the generation of cell populations for analysis and transplantation for therapeutic use.

Embryonic stem cell-derived embryoid bodies development in collagen gels recapitulates sprouting angiogenesis.

The formation of new blood vessels proceeds by both vasculogenesis and angiogenesis. The development of models, which fully recapitulate spatio-temporal events involved during these processes, are crucial to fully understand their mechanisms of regulation. In vitro differentiation of murine embryonic stem (ES) cells has been shown to be a useful tool to investigate factors and genes potentially involved in vasculogenesis (Hirashima et al, 1999; Risau et al, 1988; Vittet et al, 1996; Wang et al, 1992; Wartenberg et al, 1998). We asked here whether this model system can also recapitulate angiogenesis, which may offer new means to study mechanisms involved in this process. ES-derived embryoid bodies (EBs) obtained after 11 days of differentiation, in which a primitive vascular network had formed, were then subcultured into a type I collagen matrix. In the presence of angiogenic growth factors, EBs rapidly developed branching pseudopods. Whole mount immunostainings with a PECAM antibody revealed that more than 75% EBs displayed, within a few days, a large number of endothelial outgrowths that can give tube-like structures with concomitant differentiation of alpha-smooth muscle actin positive cells, thus evoking sprouting angiogenesis. High expression levels of flk1 (VEGFR2), flt1 (VEGFR1), tie-1, and tie-2 are also found, indicating that budding endothelial cells displayed an angiogenic phenotype. The endothelial sprouting response was specifically induced by angiogenic factors with a major contribution of vascular endothelial growth factor (VEGF). Known angiostatic agents, such as platelet factor 4 (PF4), angiostatin, and endostatin inhibited the formation of endothelial sprouts induced by angiogenic factors. Moreover, consistent with the in vivo phenotype, VE-cadherin deficient EBs failed to develop angiogenesis in this model. ES cell differentiation can then recapitulate, in addition to vasculogenesis, the early stages of sprouting angiogenesis. This model system, in which genetic modifications can be easily introduced, may be of particular interest to investigate unsolved questions and molecular mechanisms involved in blood vessel formation.

Monochorionic monoamnionic twins: vaginal delivery.

Monochorionic monoamnionic pregnancies are rare and have a poor obstetric prognosis. A single amniotic sac promotes cord knotting and entanglement with a high risk of fetal anoxia. The response to this risk has been obstetric management consisting of routine cesarean section at 32 weeks of gestation or when pulmonary maturity is attained. This approach is called into question by the series of seven monochorionic monoamnionic pregnancies we present here. Such pregnancies do indeed require increased surveillance to term, but we think it is possible to apply the usual obstetric management of twin pregnancies.

Antenatal diagnosis of Bart's hydrops fetalis [correction of homozygous alpha thalassemia]. A case report.

OBJECTIVE: Diagnosis of the Bart's hydrops fetalis [corrected]. METHOD: Bart's hydrops fetalis [corrected] was discovered by chance in the fetus of a female Chinese patient. Major intrauterine growth retardation, oligohydramnios, an immobile fetus, and cardiomegaly were the principal echographic signs. Cordocentesis showed fetal anemia, and electrophoresis of fetal hemoglobin revealed the presence of Bart's hemoglobin. RESULT: As there is no known effective treatment, termination of pregnancy was proposed to the patient. CONCLUSIONS: Bart's hydrops fetallis [corrected] is a lethal condition. Early echographic signs (cardiothoracic index >0.50, placental thickening) can be screened during weeks 17-18 or even during weeks 13-14 of gestation. These signs would permit a reduction of invasive examinations in couples at risk.