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81.

BACKGROUND:

Cornelia de Lange syndrome (CDLS) is a rare multiple congenital anomaly syndrome characterized by a distinctive facial appearance, developmental delay, growth retardation, low birth weight, skeletal formation anomaly, and hirsutism.

CASE:

Here for the first time a case of CDLS from Iran, a 15-week-old male infant who was refereed as a case of multiple congenital anomalies. Clinical investigation showed that the child was a case of CDLS.

CONCLUSION:

This is the first case report with CDLS in Iran.  相似文献   
82.
Marijuana is the most commonly abused illicit drug by pregnant women. Its major psychoactive constituent, Δ9‐THC (Δ9‐tetrahydrocannabinol), crosses the placenta and accumulates in the f?tus, potentially harming its development. In humans, marijuana use in early pregnancy is associated with miscarriage, a fetal alcohol‐like syndrome, as well as learning disabilities, memory impairment, and ADHD in the offspring. Classical studies in the 1970 s have reached disparate conclusions as to the teratogenic effects of cannabinoids in animal models. Further, there is very little known about the immediate effects of Δ9‐THC on early embryogenesis. We have used the chick embryo as a model in order to characterize the effects of a water‐soluble Δ9‐THC analogue, O‐2545, on early development. Embryos were exposed to the drug (0.035 to 0.35 mg/ml) at gastrulation and assessed for morphological defects at stages equivalent to 9–14 somites. We report that O‐2545 impairs the formation of brain, heart, somite, and spinal cord primordia. Shorter incubation times following exposure to the drug show that O‐2545 interferes with the initial steps of head process and neural plate formation. Our results indicate that the administration of the cannabinoid O‐2545 during early embryogenesis results in embryotoxic effects and serves to illuminate the risks of marijuana exposure during the second week of pregnancy, a time point at which most women are unaware of their pregnancies. Birth Defects Res (Part B) 83:477–488, 2008. © 2008 Wiley‐Liss, Inc.  相似文献   
83.
目的:分析改良颅窝减压术在Chiari畸形Ⅰ型患者中的应用及其对脑脊液动力学的影响。方法:收集我院2013年3月至2015年3月诊治的82例Chiari畸形Ⅰ型患者,按照抽签法分为对照组和观察组,各41例,对照组予以传统颅窝减压术,观察组予以改良颅窝减压术,比较两组临床疗效、并发症、脑脊液动力学[包含脑导管层面、脑桥腹侧平面、C3腹侧平面头端最大峰值流速(VDmax)、尾端最大峰值流速(VUmax)、每博出量(SV)]以及颅脊角变化。结果:观察组疾病控制率(95.12%)显著高于对照组(80.49%)(P0.05),并发症发生率(4.88%)低于对照组(19.51%)(P0.05)。术后,观察组脑导管层面、脑桥腹和C3腹侧平面VDmax、VUmax、SV和颅脊角、枕骨大孔径值均明显优于对照组(P0.05)。结论:改良颅窝减压术在Chiari畸形Ⅰ型患者中的临床效果值得肯定,能够改善患者的脑脊液动力学。  相似文献   
84.
Giant congenital melanocytic nevi may be symptomatically isolated or syndromic. Associations with capillary malformations are exceptional, and development of epidermal cysts has not been described. A 71‐year‐old patient with a giant congenital melanocytic nevus (CMN) of the lower back, buttocks, and thighs was asymptomatic except for unexpected hemorrhage during partial surgical excision years before. Blunt trauma at age 64 initiated recurrent, severe pain under the nevus; multiple large epidermal cysts then developed within it. Imaging and biopsy showed a large, non‐pulsatile venous malformation intermingled with the deep nevus. A low‐abundance, heterozygous BRAF c.1799T>A (p.V600E) mutation was present in both gluteal and occipital congenital nevi; additional mutations in NRAS, GNAQ, GNA11, HRAS, or PIK3CA were undetectable. This is the first demonstration of a recurrent BRAF mutation in multiple large congenital nevi from the same individual, confirming that this malformation can have multiple genetic origins. Early constitutive activation of BRAF can therefore cause unusual associations of giant nevi with vascular malformations, indicating that both pigment and endothelial cell physiology may be affected by mosaic RASopathies.  相似文献   
85.
86.
Transforming growth factor beta (TGF-beta) proteins play important roles in morphogenesis of many craniofacial tissues; however, detailed biological mechanisms of TGF-beta action, particularly in vivo, are still poorly understood. Here, we deleted the TGF-beta type I receptor gene Alk5 specifically in the embryonic ectodermal and neural crest cell lineages. Failure in signaling via this receptor, either in the epithelium or in the mesenchyme, caused severe craniofacial defects including cleft palate. Moreover, the facial phenotypes of neural crest-specific Alk5 mutants included devastating facial cleft and appeared significantly more severe than the defects seen in corresponding mutants lacking the TGF-beta type II receptor (TGFbetaRII), a prototypical binding partner of ALK5. Our data indicate that ALK5 plays unique, non-redundant cell-autonomous roles during facial development. Remarkable divergence between Tgfbr2 and Alk5 phenotypes, together with our biochemical in vitro data, imply that (1) ALK5 mediates signaling of a diverse set of ligands not limited to the three isoforms of TGF-beta, and (2) ALK5 acts also in conjunction with type II receptors other than TGFbetaRII.  相似文献   
87.
Notch signaling is essential for embryonic vascular development in mammals and other vertebrates. Here we show that mouse embryos with conditional activation of the Notch1 gene in endothelial cells (Notch1 gain of function embryos) exhibit defects in vascular remodeling increased diameter of the dorsal aortae, and form arteriovenous malformations. Conversely, embryos with either constitutive or endothelial cell‐specific Notch1 gene deletion also have vascular defects, but exhibit decreased diameter of the dorsal aortae and form arteriovenous malformations distinctly different from the Notch1 gain of function mutants. Surprisingly, embryos homozygous for mutations of the ephrinB/EphB pathway genes Efnb2 and Ephb4 exhibit vascular defects and arteriovenous malformations that phenocopy the Notch1 gain of function mutants. These results suggest that formation of arteriovenous malformations in Notch1 gain of function mutants and ephrinB/EphB pathway loss of function mutant embryos occurs by different mechanisms. genesis 48:146–150, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
88.
This paper describes the instances of gross hand and limb malformations in the free-ranging macaques in the forested region of the Kowloon peninsula of Hong Kong. The incidence in this location is compared to that of other macaque groups, most notably the Japanese and rhesus macaques in free-ranging and captive conditions. Etiology is linked to what is known about suspected local teratogenic agents, particularly in pesticides and fuel emissions.  相似文献   
89.
The levels of neurotensin (NT) and its metabolite, the N-terminal octapeptide (NT1-8), identified by HPLC and measured by RIA, were increased in the hepatic-portal circulation of the anesthetized rat during perfusion of the small intestine with a lipid solution, while levels of both peptides remained unchanged in the general circulation. There was no significant arteriovenous difference for NT or NT1-8 during saline perfusion of the small intestine. Plasma collected from the superior mesenteric vein during the infusion of [3H]NT into the superior mesenteric artery showed major peaks of radioactivity with the retention times of NT1-8 and NT1-11 on HPLC. Only 12% of the radioactivity recovered from plasma was intact NT. These studies demonstrate that chromatographically identified NT and its metabolite, NT1-8, are elevated in the portal circulation but not systemic circulation during lipid perfusion and that the small intestine may be both the site of release and metabolism of NT.  相似文献   
90.
Gene ablation studies in mice have revealed roles for gap junction proteins (connexins) in heart development. Of the 20 connexins in vertebrates, four are expressed in developing heart: connexin37 (Cx37), connexin40 (Cx40), connexin43 (Cx43), and connexin45 (Cx45). Although each cardiac connexin has a different pattern of expression, some heart cells coexpress multiple connexins during cardiac morphogenesis. Since different connexins could have overlapping functions, some developmental phenotypes may only become evident when more than one connexin is ablated. In this study, we interbred Cx40(-/-) and Cx43(-/-) mice to generate mice lacking both Cx40 and Cx43. Cx40(-/-)Cx43(-/-) mice die around embryonic day 12.5 (E12.5), much earlier than either Cx40(-/-) or Cx43(-/-) mice, and they exhibit malformed hearts with ventricles that are abnormally rotated, suggesting a looping defect. Some Cx40(-/-)Cx43(-/-) animals also develop head defects characteristic of exencephaly. In addition, we examined mice lacking both Cx40 and Cx37 and found a high incidence of atrial and ventricular septal defects at birth. These results provide further evidence for the importance of gap junctions in embryonic development. Moreover, ablating different pairs of cardiac connexins results in distinct heart defects, suggesting both common and unique functions for Cx40, Cx43, and Cx37 during cardiac morphogenesis.  相似文献   
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