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81.
An international advisory group met at the National Institutes of Health in Bethesda, Maryland in 2017, to discuss a new classification system for the ectodermal dysplasias (EDs) that would integrate both clinical and molecular information. We propose the following, a working definition of the EDs building on previous classification systems and incorporating current approaches to diagnosis: EDs are genetic conditions affecting the development and/or homeostasis of two or more ectodermal derivatives, including hair, teeth, nails, and certain glands. Genetic variations in genes known to be associated with EDs that affect only one derivative of the ectoderm (attenuated phenotype) will be grouped as non‐syndromic traits of the causative gene (e.g., non‐syndromic hypodontia or missing teeth associated with pathogenic variants of EDA “ectodysplasin”). Information for categorization and cataloging includes the phenotypic features, Online Mendelian Inheritance in Man number, mode of inheritance, genetic alteration, major developmental pathways involved (e.g., EDA, WNT “wingless‐type,” TP63 “tumor protein p63”) or the components of complex molecular structures (e.g., connexins, keratins, cadherins).  相似文献   
82.
In this report we describe the occurrence of severe mesomelic shortening of the forearms due to hypoplasia of the ulnae with severe radial bowing. In contrast to the mesomelic dysplasias, i.e. Langer type of mesomelic dwarfism, this apparently autosomal dominantly inherited skeletal anomaly occurred as an isolated anomaly without concomitant involvement of shanks or other parts of the skeleton, and did not influence final adult height.  相似文献   
83.
We report a female patient who had a scalp hemangioma, a cleft uvula, an upper sternal defect, pectus excavatum, arachnodactyly, pes planus, and joint hypermobility. She had rupture of an aortic aneurysm after minor trauma at 11 years of age. At 17 years of age, elective repair of a dilated, ectatic aorta was complicated by cerebral ischemia. Other vascular abnormalities in the proband included an aneurysm of the left subclavian artery, atresia of the right carotid artery, and calcified cerebral aneurysms. We believe that the proband's physical anomalies are best described by the PHACE (posterior fossa brain malformations, hemangiomas, arterial anomalies, coarctation of the aorta and cardiac defects, and eye abnormalities) phenotypic spectrum. This spectrum of physical anomalies also includes sternal clefting and hemagiomas as part of the sternal malformation/vascular dysplasia (SM/VD) association, as found in our patient, and the acronym PHACES has also been used. We consider that the PHACE phenotypic spectrum is likely to be broader than previously recognized and includes orofacial clefting and aortic dilatation and rupture. Our patient also had skeletal anomalies that lead to consideration of Marfan syndrome as a diagnosis. It should be recognized that there is clinical overlap between PHACE syndrome and Marfan syndrome when aortic dilatation is present. We would also like to emphasize the minor nature of the cutaneous findings in our patient despite her severe vascular complications. This is in contrast to previous reports of large or multiple hemangiomas in PHACE syndrome. Published 2002 Wiley‐Liss, Inc.  相似文献   
84.
We report on an infant with broad and severely angulated short femora as the most salient manifestation of a generalized skeletal dysplasia. Other findings include congenital bowing of other long bones, narrow thorax, platyspondyly, micrognathia, and skin dimples. A marked improvement of the bowing and of the irregular flare of the metaphyses was noted over a period of 6 mo. Congenital bowing of long bones can be an isolated finding or associated with other anomalies, so the purpose of reporting all cases is important for further nosologic and pathogenetic elucidation. Because of the severity of the femoral involvement, the condition has been called kyphomelic dysplasia. It may be an autosomal recessive trait. recessive trait.  相似文献   
85.
Ectodermal dysplasias (EDs) are developmental disorders affecting tissues of ectodermal origin including hair, nails, teeth and sweat glands. Ectodermal dysplasia of hair, nails and teeth is a rare type of congenital disorder characterized by sparse and thin hair, dystrophic finger-and toenails and missing and abnormal teeth. In an effort to understand the molecular basis of this form of ED a family of Pakistani origin with an autosomal recessive pattern of inheritance was ascertained from a remote region in Pakistan. The clinical features of the affected individuals included thin and fine hair on the scalp, dystrophic and flat nails, absent or sparse eyebrows and eyelashes, missing and abnormal teeth, and thin body hair. A human genome scan carried out using microsatellite markers mapped the disease locus in this family to chromosome 18q22.1–18q22.3. A maximum two-point LOD score of 2.73 (θ= 0.0) was obtained at marker D18S541. Multipoint linkage analysis resulted in a maximum LOD score of 3.42 obtained with several markers, including D18S1125, ATA82B02, D18S848, D18S488, D18S1091, and D18S485, which supported the linkage. The linkage interval is flanked by markers D18S857 and D18S815, which corresponds to a region of 17.32 cM according to Rutgers combined linkage and physical map (build 36). This region covers 8.63 Mb according to the sequence-based physical map. Three candidate genes, CDH7, CDH19 and ZNF407 , from the linkage interval were sequenced and found to be negative for functional sequence variants. This study is the first step towards the identification of a gene involved in hair, nails and teeth type ED.  相似文献   
86.
Psammomatoid (juvenile) ossifying fibroma of the orbit   总被引:2,自引:0,他引:2  
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87.
The present study was undertaken to evaluate the systemic absorption and cervical tissue uptake of all-transretinoic acid (TRA), delivered via a collagen spongecervical cap delivery device in patients with intraepithelial cervical dysplasia. Ten patients with histologically proven mild or moderate cervical dysplasia were included in this pharmacologic study. The two TRA concentrations (0.05% and 0.372%) selected for study represent the starting and maximally tolerated doses used in phase I clinical trial. All-trans-retinoic-11-3H acid (3H-TRA, 500 Ci) was used to facilitate cervical tissue uptake studies. Cervical biopsies and post-treatment blood samples were obtained from each patient after TRA exposure. The uptake of TRA into cervical tissues four hours after drug administration was significantly increased at the maximally tolerated TRA dose. There was a rapid decrease in cervical tissue concentration of TRA at the 0.372% dose between 4 and 24 h after drug exposure, suggesting a relatively short elimination half-life of TRA in cervical tissues. HPLC analysis of post-treatment blood samples indicate that there was no systemic absorption of TRA after local cervical administration.  相似文献   
88.
Summary The term dysplasia is used increasingly in gastrointestinal pathology. Dysplasia denotes an unequivocal neoplastic epithelial alteration without invasive growth and is synonymous with the term intraepithelial neoplasia. Dysplasia is the paradigm of a precancerous lesion. Confusion arises because some pathologists do not use the term in the above-defined sense but to describe regenerative, inflammatory and reactive changes. It is essential to separate these kinds of non-neoplastic epithelial changes from neoplastic dyplasia because the clinical consequences are completely different. The general morphology and the grading of dysplasia are described. Most dysplasias in the gastrointestinal tract are the polypoid lesion; dysplasias in flat mucosa are uncommon. Knowledge of the incidence of dysplasia in the gastrointestinal tract is important for the concept of secondary cancer prevention.  相似文献   
89.
In a review of cases of fibrous cartilaginous dysplasia of bone, five of fibrocartilaginous lesions were found to be different in clinical behavior and radiographic and morphologic features from the others. We have named these previously undescribed tumors fibrocartilaginous mesenchymomas with low-grade malignancy in the fibrous elements.Dr. Bertoni is a visiting surgical pathologist from the Servizio di Anatomia ed Istologia Patologica, Bologna, Italy  相似文献   
90.
支气管肺发育不良(BPD)是早产儿最常见的慢性肺部疾病。BPD由多种因素引起,其本质是在遗传易感性的基础上,各种环境因素引起的肺损伤和发育中的未成熟肺修复之间的不平衡。研究显示BPD致病分子机理多涉及炎症细胞因子、非编码RNA和各种信号通路因子的异常表达调控。这些相关基因的异常表达,不仅影响了胚胎或早期胎儿肺的正常发育,并阻碍了新生肺损伤后肺的修复,或导致肺功能不全。单独或协同影响了BPD的发生发展。同时研究发现环境风险因素如高氧暴露、炎症导致基因表达异常也是BPD发生的原因之一,环境和基因共同作用推动了BPD的发生发展。  相似文献   
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