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221.
We describe a rare giant placental chorioangioma in a patient who had a favorable outcome with close prenatal surveillance in a 28‐year‐old primigravida who was referred to our clinic for ultrasound evaluation of a suspected placental mass at 23 weeks' gestation. A detailed ultrasound scan revealed a well‐circumscribed, echogenic lesion measuring 11.0 × 10.3 × 7.3 cm and protruding into the amniotic cavity. A diagnosis of placental chorioangioma was made and intensive prenatal surveillance was scheduled. A small‐for‐gestational age (2,325 g) but normal female neonate was delivered at 37 weeks by cesarean section and discharged from hospital on the second day of the delivery. A giant chorioangioma may not cause any adverse effect to the fetus and may not require any medication or invasive intervention. © 2014 Wiley Periodicals, Inc. J Clin Ultrasound 43 :254–256, 2015 相似文献
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Franck Rapaport Bertrand Boisson Anne Gregor Vivien Bziat Stphanie Boisson-Dupuis Jacinta Bustamante Emmanuelle Jouanguy Anne Puel Jrmie Rosain Qian Zhang Shen-Ying Zhang Joseph G. Gleeson Lluis Quintana-Murci Jean-Laurent Casanova Laurent Abel Etienne Patin 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(3)
Genetic variants underlying life-threatening diseases, being unlikely to be transmitted to the next generation, are gradually and selectively eliminated from the population through negative selection. We study the determinants of this evolutionary process in human genes underlying monogenic diseases by comparing various negative selection scores and an integrative approach, CoNeS, at 366 loci underlying inborn errors of immunity (IEI). We find that genes underlying autosomal dominant (AD) or X-linked IEI have stronger negative selection scores than those underlying autosomal recessive (AR) IEI, whose scores are not different from those of genes not known to be disease causing. Nevertheless, genes underlying AR IEI that are lethal before reproductive maturity with complete penetrance have stronger negative selection scores than other genes underlying AR IEI. We also show that genes underlying AD IEI by loss of function have stronger negative selection scores than genes underlying AD IEI by gain of function, while genes underlying AD IEI by haploinsufficiency are under stronger negative selection than other genes underlying AD IEI. These results are replicated in 1,140 genes underlying inborn errors of neurodevelopment. Finally, we propose a supervised classifier, SCoNeS, which predicts better than state-of-the-art approaches whether a gene is more likely to underlie an AD or AR disease. The clinical outcomes of monogenic inborn errors, together with their mode and mechanisms of inheritance, determine the levels of negative selection at their corresponding loci. Integrating scores of negative selection may facilitate the prioritization of candidate genes and variants in patients suspected to carry an inborn error.Negative (or purifying) selection is the natural process by which deleterious alleles are selectively purged from the population (1). In diploid species, the strength of negative selection at a given locus is predicted to increase with decreasing fitness and increasing dominance of the genetic variants controlling traits: Variation causing early death in the heterozygous state are the least likely to be transmitted to the next generation, as their carriers have fewer offspring than noncarriers (2). Human genetic variants that cause severe diseases are, thus, expected to be the primary targets of negative selection, particularly for diseases affecting heterozygous individuals. In humans, several studies have ranked protein-coding genes according to their levels of negative selection (3–5). Nevertheless, the extent to which negative selection affects human disease-causing genes, and the factors determining its strength, remain largely unknown, particularly because our knowledge of the severity, mode, and mechanism of inheritance of the corresponding human diseases remains incomplete (3, 6–8).The strength of negative selection at a given gene has been traditionally approximated by comparing the coding sequence of the gene in a given species with that of one or several closely related species; it depends on the proportion of amino acid changes that have accumulated during evolution (9–11). With the advent of high-throughput sequencing, intraspecies metrics have been developed, based on the comparison of the probability of predicted loss-of-function (pLOF) mutations for a gene under a random model with the frequency of pLOF mutations observed in population databases (5, 12, 13), which capture the species-specific evolution of genes. Using an interspecies-based method and a hand-curated version of the Online Mendelian Inheritance in Man (hOMIM) database, a previous study elegantly showed that most human genes for which mutations cause highly penetrant diseases, including autosomal dominant (AD) diseases in particular, evolve under stronger negative selection than genes associated with complex disorders (6). However, other studies based on OMIM genes have reported conflicting results (3, 14–17), probably due to the incompleteness and heterogeneity of the datasets used. Moreover, no study has yet addressed this problem with intraspecies metrics, even though it has been suggested that the choice of the reference species for interspecies metrics contributes to discrepancies across studies (6).We aimed to improve the identification of the drivers of negative selection acting on human disease-causing genes, by developing a negative selection score combining several informative intraspecies and interspecies statistics, focusing on inborn errors of immunity (IEI). IEI, previously known as primary immunodeficiencies (18), are genetic diseases that disrupt the development or function of human immunity. They form a large and expanding group of genetic diseases that has been widely studied, and they are well characterized physiologically (immunologically) and phenotypically (clinically) (19–21). IEI are often symptomatic in early childhood, and at least until the turn of the 20th century and the introduction of antibiotics, most individuals with IEI probably died before reaching reproductive maturity. Accordingly, IEI genes have probably been under strong negative selection from the dawn of humankind until very recently. In this study, we investigated whether the severity of IEI and their mode and mechanism of inheritance have left signatures of negative selection of various intensities in the corresponding human genes. Furthermore, we validated our model on genes underlying inborn errors of neurodevelopment (IEND), another group of well-characterized severe genetic diseases. 相似文献
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Clinical and molecular characterization of seven Egyptian families with autosomal recessive robinow syndrome: Identification of four novel ROR2 gene mutations 下载免费PDF全文
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Malihe?Vasegh Farhad?Koohpeyma Hossein?Kargar JahromiEmail author Seyed?Hamid?Bathaee Roza?Saberi Sara?Azhdari Mohammad?Farzam 《Comparative clinical pathology》2015,24(2):399-402
Cyclophosphamide is an antineoplastic medicine that causes disorder in functions of the body systems. Thus, the purpose of this study is to investigate the effect of hydroalcoholic extract of saffron on improving the complications of cyclophosphamide on sex hormones. Fifty-six adult female Wistar rats were randomly divided into seven groups; control, sham (received distilled water, solvent extract, and drug), experimental groups 1, 2, and 3 (received cyclophosphamide (5 mg/kg/bw) + hydroalcoholic extract of saffron (2, 1, and 0.5 g/kg/bw), experimental group 4 (saffron 2 g/kg/bw), and experimental group 5 (cyclophosphamide 5 mg/kg/bw). Cyclophosphamide was given intraperitoneally, and extract by gavage was prescribed for 21 days. At the end of the experiment, after blood and preparation of serum, ELISA method was used for measuring the estrogen, progesterone, FSH, and LH hormones. Data and LSD test were analyzed with SPSS software (version 18). Results show that the concurrent use of low-dose cyclophosphamide and saffron extract can reduce toxic effect of cyclophosphamide on pituitary-gonadal axis and cause estrogen to be produced. 相似文献
228.
Hamid Badrian Amin Davoudi Meysam Molazem Mohammad Hossein Zare 《Journal of Indian Prosthodontic Society》2015,15(3):263-267
Background:
Dentistry equipment are exposed to different types of pathogenic microorganisms. The aim of this study was to investigate the effect of spraying three different types of disinfectants on condensational silicones after 5 and 10 min.Materials and Methods:
Totally, 66 circular samples of condensational silicone impression materials of 1 cm diameter and 2 mm thickness were contaminated by Staphylococcus aureus, Pseudomonas aeruginosa, and Candida albicans fungus. Except for control samples, all of them were disinfected with sodium hypochlorite (NaOCl) 0.525%, Deconex and Epimax by spraying method. Afterward, they kept in plastic bags with humid rolled cotton for 5 and 10 min. In order to isolate microbiotas, the samples were immersed in 2% trypsin for 1 h and diluted with normal saline in a portion of 1, 1/2, and 1/4. The trypsin suspensions were transferred to culture plates for incubation and colony-forming unit assay. The data were analyzed by Mann–Whitney test and SPSS software version 16 at a significant level of 0.05.Results:
There was a meaningful difference between disinfection effects of Epimax-Deconex for all mentioned microorganisms after 5 min (P = 0.034), and between disinfection effects of NaOCl 0.525%-Epimax for S. aureus (P = 0.043) and P. aeruginosa (P = 0.046) after 5 min. Furthermore, there was a meaningful difference between disinfection effects of Epimax-Deconex (P = 0.034) and NaOCl 0.525%-Epimax (P = 0.034) for P. aeruginosa after 10 min.Conclusion:
Condensational silicone can be effectively disinfected by spraying tested three disinfecting agents. More specifically, Deconex showed the best results compared to the other agents.Key Words: Condensational silicone, disinfection, impression materials, spray 相似文献229.