527 resultados para Malformations congénitales majeures
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We report on the molecular characterization of a microdeletion of approximately 2.5 Mb at 2p11.2 in a female baby with left congenital aural atresia, microtia, and ipsilateral internal carotid artery agenesis. The deletion was characterized by fluorescence in situ hybridization, array comparative genomic hybridization, and whole genome re-sequencing. Among the genes present in the deleted region, we focused our attention on the FOXI3 gene. Foxi3 is a member of the Foxi class of Forkhead transcription factors. In mouse, chicken and zebrafish Foxi3 homologues are expressed in the ectoderm and endoderm giving rise to elements of the jaw as well as external, middle and inner ear. Homozygous Foxi3-/- mice have recently been generated and show a complete absence of the inner, middle, and external ears as well as severe defects in the jaw and palate. Recently, a 7-bp duplication within exon 1 of FOXI3 that produces a frameshift and a premature stop codon was found in hairless dogs. Mild malformations of the outer auditory canal (closed ear canal) and ear lobe have also been noted in a fraction of FOXI3 heterozygote Peruvian hairless dogs. Based on the phenotypes of Foxi3 mutant animals, we propose that FOXI3 may be responsible for the phenotypic features of our patient. Further characterization of the genomic region and the analysis of similar patients may help to demonstrate this point. © 2015 Wiley Periodicals, Inc.
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Transient exposure of brown trout embryos from fertilization until hatch (70 days) to 17β-estradiol (E2) was investigated. Embryos were exposed to 3.8 and 38.0 ng/L E2 for 2h, respectively, under four scenarios: (A) exposure once at the day of fertilization (0 days post-fertilization, dpf), (B) once at eyeing stage (38 dpf), (C) weekly exposure until hatch or (D) bi-weekly exposure until hatch. Endpoints to assess estrogen impact on embryo development were fertilization success, chronological sequence of developmental events, hatching process, larval malformations, heart rate, body length and mortality. Concentration-dependent acceleration of development until median hatch was observed in all exposure scenarios with the strongest effect observed for embryos exposed once at 0 dpf. In addition, the hatching period was significantly prolonged by 4-5 days in groups receiving single estrogen exposures (scenarios A and B). Heart rate on hatching day was significantly depressed with increasing E2 concentrations, with the strongest effect observed for embryos exposed at eyeing stage. Estrogenic exposure at 0 dpf significantly reduced body length at hatch, not depending on whether this was a single exposure or the first of a series (scenarios A and D). The key finding is that even a single, transient E2 exposure during embryogenesis had significant effects on brown trout development. Median hatch, hatching period, heart rate and body length at hatch were found to be highly sensitive biomarkers responsive to estrogenic exposure during embryogenesis. Treatment effects were observable only at the post-hatch stage.
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Infections with Schmallenberg virus (SBV), a novel Orthobunyavirus transmitted by biting midges, can cause abortions and malformations of newborns and severe symptoms in adults of domestic and wild ruminants. Understanding the temporal and spatial distribution of the virus in a certain territory is important for the control and prevention of the disease. In this study, seroprevalence of antibodies against SBV and the spatial spread of the virus was investigated in Swiss dairy cattle applying a milk serology technique on bulk milk samples. The seroprevalence in cattle herds was significantly higher in December 2012 (99.5%) compared to July 2012 (19.7%). This high between-herd seroprevalence in cattle herds was observed shortly after the first detection of viral infections. Milk samples originating from farms with seropositive animals taken in December 2012 (n=209; mean 160%) revealed significantly higher S/P% ratios than samples collected in July 2012 (n=48; mean 103.6%). This finding suggests a high within-herd seroprevalence in infected herds which makes testing of bulk tank milk samples for the identification farms with past exposures to SBV a sensitive method. It suggests also that within-herd transmission followed by seroconversion still occurred between July and December. In July 2012, positive bulk tank milk samples were mainly restricted to the western part of Switzerland whereas in December 2012, all samples except one were positive. A spatial analysis revealed a separation of regions with and without positive farms in July 2012 and no spatial clustering within the regions with positive farms. In contrast to the spatial dispersion of bluetongue virus, a virus that is also transmitted by Culicoides midges, in 2008 in Switzerland, the spread of SBV occurred from the western to the eastern part of the country. The dispersed incursion of SBV took place in the western part of Switzerland and the virus spread rapidly to the remaining territory. This spatial pattern is consistent with the hypothesis that transmission by Culicoides midges was the main way of spreading.
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INTRODUCTION A marker predictive of hematoma expansion in the central nervous system could aid the selection of patients for hemostatic or surgical treatment. CASE REPORT Here, we present a 83-year-old patient with acute spinal subdural hematoma with paraparesis progressing to paraplegia. A contrast extravasation within the intraspinal hematoma was visualized on spinal MR indicating active bleeding (spinal spot sign). A second acquisition of contrast-enhanced MR images showed progression of contrast extravasation helping to different active bleeding from spinal arteriovenous malformations/fistula. CONCLUSIONS A "spinal spot sign" may be important for treatment decisions, notably in patients with incomplete neurological deficits at the time of imaging.
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Schmallenberg virus (SBV), an arthropod-borne orthobunyavirus was first detected in 2011 in cattle suffering from diarrhea and fever. The most severe impact of an SBV infection is the induction of malformations in newborns and abortions. Between 2011 and 2013 SBV spread throughout Europe in an unprecedented epidemic wave. SBV contains a tripartite genome consisting of the three negative-sense RNA segments L, M, and S. The virus is usually isolated from clinical samples by inoculation of KC (insect) or BHK-21 (mammalian) cells. Several virus passages are required to allow adaptation of SBV to cells in vitro. In the present study, the porcine SK-6 cell line was used for isolation and passaging of SBV. SK-6 cells proved to be more sensitive to SBV infection and allowed to produce higher titers more rapidly as in BHK-21 cells after just one passage. No adaptation was required. In order to determine the in vivo genetic stability of SBV during an epidemic spread of the virus the nucleotide sequence of the genome from seven SBV field isolates collected in summer 2012 in Switzerland was determined and compared to other SBV sequences available in GenBank. A total of 101 mutations, mostly transitions randomly dispersed along the L and M segment were found when the Swiss isolates were compared to the first SBV isolated late 2011 in Germany. However, when these mutations were studied in detail, a previously described hypervariable region in the M segment was identified. The S segment was completely conserved among all sequenced SBV isolates. To assess the in vitro genetic stability of SBV, three isolates were passage 10 times in SK-6 cells and sequenced before and after passaging. Between two and five nt exchanges per genome were found. This low in vitro mutation rate further demonstrates the suitability of SK-6 cells for SBV propagation.
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Atrial septal defects (ASDs) are one of the most frequent congenital cardiac malformations, accounting for about 8-10% of all congenital heart defects. The prevalence of pulmonary arterial hypertension (PAH) in adults with an ASD is 8-10%. Different clinical PAH scenarios can be encountered. At one end of the spectrum are adults with no or only mild pulmonary vascular disease and a large shunt. These are patients who can safely undergo shunt closure. In the elderly, mild residual pulmonary hypertension after shunt closure is the rule. At the other end of the spectrum are adults with severe, irreversible pulmonary vascular disease, shunt reversal and chronic cyanosis, that is, Eisenmenger syndrome. These are patients who need to be managed medically. The challenge is to properly classify ASD patients with PAH falling in between the two ends of the spectrum as the ones with advanced, but reversible pulmonary vascular disease amenable to repair, versus the ones with progressive pulmonary vascular disease not responding to shunt closure. There are concerns that adults with progressive pulmonary vascular disease have worse outcomes after shunt closure than patients not undergoing shunt closure. Due to the correlation of pulmonary vascular changes and pulmonary hemodynamics, cardiac catheterization is used in the decision-making process. It is important to consider the hemodynamic data in the context of the clinical picture, the defect anatomy and further noninvasive tests when evaluating the option of shunt closure in these patients.
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BACKGROUND Port-wine stains (PWS) are malformations of capillaries in 0.3% of newborn children. The treatment of choice is by pulsed dye LASER (PDL), and requires several sessions. The efficacy of this treatment is at present evaluated on the basis of clinical inspection and of digital photographs taken throughout the treatment. LASER-Doppler imaging (LDI) is a noninvasive method of imaging the perfusion of the tissues by the microcirculatory system (capillaries). The aim of this paper is to demonstrate that LDI allows a quantitative, numerical evaluation of the efficacy of the PDL treatment of PWS. METHOD The PDL sessions were organized according to the usual scheme, every other month, from September 1, 2012, to September 30, 2013. LDI imaging was performed at the start and at the conclusion of the PDL treatment, and simultaneously on healthy skin in order to obtain reference values. The results evidenced by LDI were analyzed according to the "Wilcoxon signed-rank" test before and after each session, and in the intervals between the three PDL treatment sessions. RESULTS Our prospective study is based on 20 new children. On average, the vascularization of the PWS was reduced by 56% after three laser sessions. Compared with healthy skin, initial vascularization of PWS was 62% higher than that of healthy skin at the start of treatment, and 6% higher after three sessions. During the 2 months between two sessions, vascularization of the capillary network increased by 27%. CONCLUSION This study shows that LDI can demonstrate and measure the efficacy of PDL treatment of PWS in children. The figures obtained when measuring the results by LDI corroborate the clinical assessments and may allow us to refine, and perhaps even modify, our present use of PDL and thus improve the efficacy of the treatment.
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The new classification system of uterine anomalies from the European Society of Human Reproduction and Embryology and the European Society for Gynaecological Endoscopy defines T-shaped and tubular-shaped infantilis uteri as 'dysmorphic'. Such malformations have been proven to be associated with poor reproductive performance. A prospective observational study was conducted with 30 infertile women with dysmorphic uterus who underwent the novel Hysteroscopic Outpatient Metroplasty to Expand Dysmorphic Uteri (HOME-DU ) technique. Incisions are made on the uterine walls with a 5 Fr bipolar electrode. The procedure was conducted in outpatients under conscious sedation, using a 5-mm office hysteroscope. The technique was successful in all cases without complications. A net increase of uterine volume was found, as measured at hysteroscopy and three-dimensional transvaginal ultrasound (P < 0.001). Uterine morphology improved in all patients but one. At mean follow-up of 15 months, clinical pregnancy rate was 57% and term delivery rate 65%. These early data support HOME-DU as safe and effective in expanding the volume and normalizing the appearance of the uterine cavity of dysmorphic uteri. Although the cohort was small, pregnancy and live births outcomes were favourable in this poor-prognosis group, implying desirable benefits, which should be compared with other techniques.
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Cell competition is a conserved mechanism where slow proliferating cells (so called losers) are eliminated by faster proliferating neighbors (so called winners) through apoptosis.(1) It is an important process which prevents developmental malformations and maintains tissue fitness in aging adults.(2) Recently, we have shown that the probability of elimination of loser cells correlates with the surface of contact between losers and winners in Myc-induced competition.(3) Moreover, we have characterized an active mechanism that increases the surface of contact between losers and winners, hence accelerating the elimination of loser cells. This is the first indication that cell shape and mechanics can influence cell competition. Here, we will discuss the consequence of the relationship between shape and competition, as well as the relevance of this model for other modes of competition.
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Cell-cell intercalation is used in several developmental processes to shape the normal body plan. There is no clear evidence that intercalation is involved in pathologies. Here we use the proto-oncogene myc to study a process analogous to early phase of tumour expansion: myc-induced cell competition. Cell competition is a conserved mechanism driving the elimination of slow-proliferating cells (so-called 'losers') by faster-proliferating neighbours (so-called 'winners') through apoptosis and is important in preventing developmental malformations and maintain tissue fitness. Here we show, using long-term live imaging of myc-driven competition in the Drosophila pupal notum and in the wing imaginal disc, that the probability of elimination of loser cells correlates with the surface of contact shared with winners. As such, modifying loser-winner interface morphology can modulate the strength of competition. We further show that elimination of loser clones requires winner-loser cell mixing through cell-cell intercalation. Cell mixing is driven by differential growth and the high tension at winner-winner interfaces relative to winner-loser and loser-loser interfaces, which leads to a preferential stabilization of winner-loser contacts and reduction of clone compactness over time. Differences in tension are generated by a relative difference in F-actin levels between loser and winner junctions, induced by differential levels of the membrane lipid phosphatidylinositol (3,4,5)-trisphosphate. Our results establish the first link between cell-cell intercalation induced by a proto-oncogene and how it promotes invasiveness and destruction of healthy tissues.
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Developmental Dyslexia is a reading disorder that affects individuals that possess otherwise normal intelligence. Until the four candidate dyslexia susceptibility genes were discovered, the cause of cortical malformations found in post mortem dyslexic brains was unclear. Normal brain development is crucial for the proper wiring of the neural circuitry that allow an individual to perform cognitive tasks like reading. For years, familial and twin studies have suggested that there was a genetic basis to the causation of dyslexia. Kiaa0319 was among the candidate dyslexia susceptibility genes that were ascertained. KIAA0319 is located on Chromosome 6p22.2-22.3 and has been found to exhibit differential spatial-temporal expression patterns in the brain throughout development, which suggests that the polycystic kidney disease (PKD) domain encoded by KIAA0319 facilitates cell-cell adhesion to enable neuronal precursors to crawl up the radial glia during neuronal migration. With the knowledge of KIAA0319 involvement in early neurogenesis, we were interested in determining how different KIAA0319 expression may impact cortical neurons in layer II and III during early adulthood. We show that KIAA0319 knockdown in cortical pyramidal neurons significantly reduces the dendritic spine density. Studies have shown that changes in dendritic spine morphology and density affect properties of neural circuitry. Henceforth, this finding may reveal a link between the Kiaa0319 gene and the deficit of the neural processing task of reading due to reduced spines density. Finding a correlation between Kiaa0319 expression and its influence on dendritic spine development may lead to a greater insight of a direct link between the dyslexia susceptibility gene and the biological mechanism that causes dyslexia.
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This MPH thesis consists of (1) literature review of the relatively new synthetic persistent organic pollutants (POP), polybrominated diphenyl ethers (PBDEs), a type of flame retardant posing a potential public health hazard, (2) Presentation of data on PBDE levels in dryer lint from Dallas, TX and Hamburg, Germany. ^ PBDEs are used as additive fire retardants in plastics, polyurethane foam and electronic equipment to reduce flammability and thus save life and property. PBDEs have been widely used beginning in the 1970s. They resemble polychlorinated biphenyls (PCBs) in structure and toxicity. PBDEs are found in environmental sediments, sludges, and wildlife and even in human blood, milk and tissues. ^ PBDEs, due to their lipophilicity, accumulate in fat and other tissues and biomagnify up the food chain, with increasing concentrations. Animal studies have suggested potential health effects including thyroid disruption, permanent learning and memory impairment, fetal malformations, developmental neurotoxicity and, at high doses, possibly cancer. ^ PBDE levels are increasing in blood and breast milk in North America, but PBDEs intake unlike PCBs appears to be not primarily through food; food PBDE levels in the U.S. are not markedly higher than in Europe yet U.S. human blood and milk levels are much higher. For this reason various exposure pathways including PBDE contaminated dust and air have been studied to better characterize routes of PBDE intake into humans. ^ The scientific literature on PBDE levels in household dust reports higher PBDE concentration in dust than that found in dryer lint; levels in the U.S are elevated compared to other countries with congeners such as BDE 47, 99, 100 and 209 predominating. The United Kingdom has elevated BDE 209 due to high usage of Deca commercial mixture. These studies suggest that indoor PBDE contamination through household dust could be a potential source of PBDE exposure and body burden especially in young children. ^ PBDE levels in dryer lint from U.S ranged from 321 to 3073 ng/g (Mean: 1138 ng/g, Median: 803 ng/g) and from Germany were from 330 to 2069 ng/g (Median: 71ng/g, Mean: 361 ng/g). High median levels in U.S samples indicate contamination of lint with PBDEs although the source of the PBDEs in lint may be from dryer electrical components or air deposition onto clothes, lint may be one source of PBDE exposure to humans. ^
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Birth defects occur in 1 of every 33 babies born in the United States, and are the leading cause of infant death. Mothers using contraceptives that become pregnant may continue to use their contraceptives after their first missed menstrual period, thus exposing their baby in utero to the contraceptive product. Progesterone is also sometimes prescribed during the first trimester of pregnancy to mothers with a history of miscarriages or infertility problems. To ensure the safety of these products, it is important to investigate whether there is an increased occurrence of babies born with birth defects to mothers using various contraceptive methods or progesterone in early pregnancy. Using data from the National Birth Defects Prevention Study (NBDPS), an ongoing multi-state, population based case-control study, this study assessed maternal exposures to IUDs, spermicides, condoms and progesterone in early pregnancy. ^ Progesterone used for threatened miscarriage during the first three months of pregnancy was associated with an increased occurrence of hypoplastic left heart (adjusted odds ratios (OR) 2.24, 95% CI 1.13-4.21), perimembranous ventricular septal defects (OR 1.64, 95% CI 1.10-2.41), septal associations (OR 2.52, 95% CI 1.45-4.24), esophageal atresia (OR 1.82, 95% CI 1.04-3.08), and hypospadias (OR 2.12, 95% CI 1.41-3.18). Mothers using progesterone for injectable contraception had increased (OR > 2.5), but insignificant odds ratios for anencephaly, septal associations, small intestinal atresias and omphalocel. Progesterone used for fertility was not associated with an increased occurrence of any birth defects examined. ^ Mothers using progesterone for fertility assistance and threatened miscarriage were very similar with respect to their demographics and pregnancy history. They also both reported similar types of progesterone. Thus, if progesterone was a causal risk factor for birth defects we would have expected to observe similar increases in risk among mothers using progesterone for both indications. Because we predominantly observed increased associations among mothers using progesterone for threatened miscarriage but not fertility assistance, it is possible the increased associations we observed were confounded by indication (i.e. progesterone was administered for vaginal bleeding which occurred as a sequelae to the formation of a congenital anomaly. ^ No significant increased associations were observed between maternal spermicide use during pregnancy and 26 of 27 types of structural malformations. While multiple statistical tests were performed we observed first trimester maternal spermicide use to be associated with a significant increased occurrence of perimembranous ventricular septal defects (OR 2.21, 95% CI 1.16-4.21). A decreased occurrence (OR < 1.0) was observed for several categories of birth defects among mothers who conceived in the first cycle after discontinuing the use of spermicides (22 of 28) or male condoms (23 of 33). ^ Overall the percent of IUD use was similar between mothers of controls and mothers of all cases in aggregate (crude OR 1.05, 95% CI 0.61-1.84). Power was limited to detect significant associations between IUD use and birth defects, however mothers using an IUD in the month immediately prior to conception or during pregnancy were not associated with an increase of birth defects. Limb defects and amniotic band sequence previously reported to be associated with IUD use during pregnancy were not found to occur among any mothers reporting the use of an IUD during pregnancy.^
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Recent studies have reported positive associations between maternal exposures to air pollutants and several adverse birth outcomes. However, there have been no assessments of the association between environmental hazardous air pollutants (HAPs) such as benzene, toluene, ethylbenzene, and xylene (BTEX) and neural tube defects (NTDs) a common and serious group of congenital malformations. Before examining this association, two important methodological questions must be addressed: (1) is maternal residential movement likely to result in exposure misclassification and (2) is it appropriate to lump defects of the neural tube, such as anencephaly and spina bifida, into a composite disease endpoint (i.e., NTDs). ^ Data from the National Birth Defects Prevention Study and Texas Birth Defects Registry were used to: (1) assess the extent to which change of residence may result in exposure misclassification when exposure is based on the address at delivery; (2) formally assess heterogeneity of the associations between known risk factors for NTDs, using polytomous logistic regression; and (3) conduct a case-control study assessing the association between ambient air levels of BTEX and the risk of NTDs among offspring. ^ Regarding maternal residential mobility, this study suggests address at delivery was not significantly different from using address at conception when assigning quartile of benzene exposure (OR 1.0, 95% CI 0.9, 1.3). On the question of effect heterogeneity among NTDs, the effect estimates for infant sex P = 0.017), maternal body mass index P = 0.016), and folate supplementation P = 0.050) were significantly different for anencephaly and spina bifida, suggesting it is often more appropriate to assess potential risk factors among subgroups of NTDs. For the main study question on the association between environmental HAPs and NTDs, mothers who have offspring with isolated spina bifida are 2.4 times likely to live in areas with the highest benzene levels (95% CI 1.1, 5.0). However, no other significant associations were observed.^ This project is the first to include not only an assessment of the relationship between environmental levels of BTEX and NTDs, but also two separate studies addressing important methodological issues associated with this question. Our results contribute to the growing body of evidence regarding air pollutant exposure and adverse birth outcomes. ^
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Neural tube defects including spina bifida meningomyelocele (SBMM) are common malformations of the brain and spinal cord, and include all abnormalities resulting from lack of closure of the developing neural tube during embryological development.^ The specific aims of this study were to determine if single nucleotide polymorphic variants (SNPs) in the folate/homocysteine metabolic pathway genes confer a risk for NTD susceptibility within this SBMM population.^ In completion of the first specific aim, two novel SNPs were identified in the FOLR1 gene in Chromosome 11of patients including one in non-coding exon 1 with a C → T transition at nucleotide position 71578317 and another in non-coding exon 3 with a T → G transversion at nucleotide position 71579123. It will be important to determine if these variants are present in the respective parents of these individuals. If they are in fact de novo variants, then these SNPs may be more likely to contribute to the birth defect.^ The second project aim was to analyze genotypes associated with SBMM risk by transmission disequilibrium tests (TDT) and association was detected on several SNPs across the folate metabolic pathway genes in this population. SNPs with significant RC-TDT values were found within the DHFR gene (rs1650723), the MTRR gene (rs327592), the FOLR2 gene (rs13908), four tightly linked variants in the FOLR3 gene (rs7925545, rs7926875, rs7926987, rs7926360) and a variant in the SLC19A1 gene (rs1888530). The product of each of these genes performs a vital function in the folate metabolic pathway. It is conceivable, therefore, that if the individual SNP or SNPs can be proven to perturb the function in some way that they may be involved in the disruption of folate metabolism and in the resulting birth defect. Validating the results of this study in other independent populations will further strengthen the evidence that dysfunction of folate enzymes and receptors may confer SBMM risk in humans. ^