Epithelial-mesenchymal transition in colonies of rhesus monkey embryonic stem cells: a model for processes involved in gastrulation

Rhesus monkey embryonic stem (rhES) cells were grown on mouse embryonic fibroblast (MEF) feeder layers for up to 10 days to form multilayered colonies. Within this period, stem cell colonies differentiated transiently into complex structures with a disc-like morphology. These complex colonies were characterized by morphology, immunohistochemistry, and marker mRNA expression to identify processes of epithelialization as well as epithelial-mesenchymal transition (EMT) and pattern formation. Typically, differentiated colonies were comprised of an upper and a lower ES cell layer, the former growing on top of the layer of MEF cells whereas the lower ES cell layer spread out underneath the MEF cells. Interestingly, in the central part of the colonies, a roundish pit developed. Here the feeder layer disappeared, and upper layer cells seemed to ingress and migrate through the pit downward to form the lower layer while undergoing a transition from the epithelial to the mesenchymal phenotype, which was indicated by the loss of the marker proteins E-cadherin and ZO-1 in the lower layer. In support of this, we found a concomitant 10-fold upregulation of the gene Snail2, which is a key regulator of the EMT process. Conversion of epiblast to mesoderm was also indicated by the regulated expression of the mesoderm marker Brachyury. An EMT is a characteristic process of vertebrate gastrulation. Thus, these rhES cell colonies may be an interesting model for studies on some basic processes involved in early primate embryogenesis and may open new ways to study the regulation of EMT in vitro.     

Estrogen receptor alpha gene polymorphisms are associated with estradiol levels in postmenopausal women

OBJECTIVE: Postmenopausal estradiol (E(2)) levels vary widely between individuals and this variation is an important determinant of diseases such as osteoporosis. It has been suggested that the estrogen receptor alpha (ESR1) gene may influence peripheral E(2) levels, but the role of common sequence variations in the ESR1 gene is unclear. METHODS: In 631 postmenopausal women and 528 men from the Rotterdam Study, a population-based, prospective cohort study of individuals aged 55 years and over, ESR1 PvuII-XbaI haplotypes were determined and correlated with plasma E2 levels. RESULTS: In women, haplotype 1 (T-A) was significantly associated with an allele-dose-dependent decrease in E(2). After adjusting for age, body mass index, years since menopause and testosterone levels, plasma E(2) levels decreased by 1.90 pmol/l per allele copy of this haplotype (P < 0.05). Extreme genotypes, representing 23 and 27% of the population, varied by 3.93 pmol/l. No association with plasma testosterone was observed. In a subset of 446 women, no association of genotype with plasma concentrations of dehydroepiandrosterone sulfate, androstenedione or estrone was seen. In men, none of the sex hormone levels was associated with the ESR1 PvuII-XbaI haplotypes. CONCLUSION: We have demonstrated a role for genetic variations in the ESR1 gene in determining post-menopausal E(2) levels in women.     

Exogenous luteinizing hormone activity may influence the treatment outcome in in vitro fertilization but not in intracytoplasmic sperm injection cycles

Additional analysis of a multinational, open-label, randomized study comparing highly purified hMG and recombinant FSH in a long protocol revealed that LH activity might favorably influence pregnancy outcome in IVF cycles.     

Interaction between risk factors for fetal growth retardation associated with abnormal umbilical artery Doppler studies

BACKGROUND: The role of antenatal risk factors associated with the occurrence of fetal growth restriction complicated by abnormal umbilical artery Doppler studies has not yet been studied extensively. We evaluated the role and the interactions of antenatal antecedents of fetal growth restriction complicated by abnormal umbilical artery end-diastolic velocities. METHODS: We compared antenatal variables in 183 pregnancies complicated by fetal growth retardation and abnormal umbilical artery Doppler studies and 549 appropriately grown fetuses with normal end-diastolic velocity waveform in the umbilical artery. Logistic regression was used to evaluate the association between antenatal variables and fetal growth retardation and to test for interaction. RESULTS: In logistic models, increasing maternal age [odds ratio (OR) 1.06, 95% confidence interval (CI) 1.01-1.11], nulliparity (OR 2.2, 95% CI 1.37-3.5), smoking during pregnancy (OR 2.56, 95% CI 1.56-4.22), preeclampsia (OR 27.5, 95% CI 15.1-49.9), first-trimester hemorrhage (OR 2.25, 95% CI 1.32-3.82) and low (< 0.2 kg/week) weight gain in pregnancy (OR 3.48, 95% CI 1.71-3.05) were significantly associated with an increased risk of fetal growth restriction complicated by abnormal Doppler studies. These risk factors were also significantly correlated with the occurrence of absent/reversed end-diastolic blood flow in the umbilical artery. Maternal smoking during pregnancy interacted negatively with preeclampsia but positively with a low weight gain in pregnancy. CONCLUSIONS: The results of this study have shown that antenatal risk factors for intrauterine growth retardation (IUGR) complicated by abnormal Doppler studies are similar to those associated with the birth of a small-for-gestational-age infant. Preeclampsia, maternal smoking and low weight gain in pregnancy play a significant causal role in the origin of fetal growth restriction associated with abnormal uteroplacental blood flow.     

Reproducibility of patch tests: comparison of identical test allergens from different commercial sources

The reproducibility of patch tests is an important determinant of the clinical value of this diagnostic procedure. The aim of the present study was to delineate comparatively the efficiency and reproducibility of identical test reagents from 2 different commercial sources. Purchased in duplicate from brial and Boots-Hermal, 30 allergens from the European standard and an extension series were simultaneously applied to Finn Chambers and affixed next to each other. Out of 2070 paired patch tests in 71 patients, 97.2% presented with concordant-negative results. 60 patch tests were classified as allergic with 95% concordant-positive results. From these paired positive patches, a subgroup of 13 (22.8%) corresponding allergens presented with minor differences in the visible strength of the allergic reaction. Generated by cobalt chloride, formaldehyde and 2-bromo-2-nitropropane-1,3-diol in 1 patient each, discordant results, i.e. 1 positive and 1 negative test in parallel, were found in only 5%. Taken together, we were able to demonstrate that patch test preparations from 2 different companies exhibited a high level of reproducibility. This standardized quality of test reagents from different suppliers provides useful information on several aspects of everyday practice.     

Comparison of transfers to Fallopian tubes or uterus after ICSI

The aim of this study was to compare the implantation rate of tubal-replaced microinjected oocytes (MIFT) versus conventional day 2 intrauterine embryo transfer in patients undergoing intracytoplasmic sperm injection (ICSI). Sixty-three patients in need of ICSI, between 18 and 37 years of age with normal menstrual cycles and fewer than four previous ICSI attempts, were randomized between April 1999 and December 2001. In the MIFT group, up to three micro-injected oocytes were transferred laparoscopically 4 h after microinjection. In the ICSI-embryo transfer group, up to three cleaving embryos were replaced into the uterine cavity 48 h after insemination. Fifty-nine patients reached the stage of oocyte retrieval; 31 patients had a day 2 embryo transfer and 28 patients had MIFT. The ongoing clinical pregnancy and implantation rate (i.e. the total number of gestational sacs with fetal heartbeat divided by the total number of transferred embryos or micro-injected oocytes) was 35 and 24% in the ICSI-embryo transfer group and 29 and 11% in the MIFT group respectively. In conclusion, this study shows a significant decrease in implantation rate in the MIFT group (P < 0.05). In this group of patients there seems to be no advantage to tubal replacement of micro-injected oocytes.     

Indeterminate cell histiocytosis. Clinical and pathologic study in a pediatric patient

Indeterminate cell histiocytosis is a rare disorder involving altered homing mechanisms of the cutaneous histiocytic/dendritic system. It has been described predominantly in adults, with less than a dozen cases in children. A 13-year-old adolescent girl presented with a 4-year history of asymptomatic erythematous nodules and plaques, measuring from 1 to 5 cm in diameter, that were located mainly on the trunk and proximal portions of her limbs. A skin biopsy showed dermal diffuse infiltration of histiocytic cells. Most of the histiocytic cells were strongly positive for S100 protein. No Birbeck granules were found. Treatment with topical steroid was ineffective. After 6 months of pure coal tar and 5% 5-fluorouracil cream, an almost total clearing of lesions was observed. An accurate diagnosis of this condition is mandatory in order to avoid unnecessary treatments. Conservative management is also discussed.     

Effect of ovarian stimulation with recombinant follicle-stimulating hormone,gonadotropin releasing hormone antagonists,and human chorionic gonadotropin on endometrial maturation on the day of oocyte pick-up

OBJECTIVE: To assess the effect of ovarian stimulation with recombinant FSH, GnRH antagonists, and hCG on endometrial maturation on the day of oocyte pick-up. DESIGN: Prospective study. SETTING: Tertiary referral center. PATIENT(S): Fifty-five women undergoing controlled ovarian hyperstimulation for IVF/intracytoplasmic sperm injection (ICSI). INTERVENTION(S): [1] Ovarian stimulation with recombinant FSH, starting on day 2 of the cycle and GnRH antagonist, starting after a median of 6 days of recombinant FSH stimulation (range, 5-12 days); [2] hCG administration for ovulation induction; and [3] aspirational biopsy of endometrium at oocyte pick-up. MAIN OUTCOME MEASURE(S): Endometrial histology at oocyte pick-up by Noyes criteria. RESULT(S): Advancement of endometrial maturation (2.5 +/- 0.1 days) as compared to the expected chronological date was observed in all antagonist cycles at oocyte retrieval. Endometrial advancement at oocyte pick-up increased in line with values of LH at initiation of stimulation and the duration of recombinant FSH treatment before the antagonist was started. CONCLUSION(S): The higher the values of LH at initiation of stimulation and the longer the duration of recombinant FSH treatment before the antagonist is started, the more advanced the endometrial maturation at oocyte pick-up.