Prenatal Development of the Facial Skeleton
D. Dixon Andrew, A.N. Hoyte David, Ronning Olli in Fundamentals of Craniofacial Growth, 2017
Entering the embryonic period of human development, which extends from the beginning of the 4th week until the end of the 8th week (Hamilton et al., 1968), rapid growth of the embryo, particularly of the neural tube, converts the flattened, disc-like structure into a more cylindrical, C-shaped form. Ventrally directed foldings in the transverse and sagittal planes turn the peripheral parts of the embryo inwards, so that the neck of the yolk sac becomes progressively constricted at the future umbilical region. This has the added effect that the outer aspect of the entire embryo now is covered by ectoderm with the endoderm transposed to the internal aspect. At this stage of development the crown-rump length (CRL) of the human embryo is no more than three 3 mm and the arm buds appear as small swellings.
A Critical Assessment of Treaty-Monitoring Bodies
Dru Bhattacharya in Global Health Disputes and Disparities, 2012
The ruling in K.L. v. Peru is particularly important because it was heralded as a landmark decision for reproductive rights “by asserting State responsibility to ensure access to legal abortion services.”15 The suit was brought by a 17-year-old female whose doctors refused to perform an abortion after she presented carrying an anencephalic fetus. Anencephaly is the most severe of fetal neural tube defects that leaves the brain partly developed, with stillbirth the most common outcome, and survival usually measured by hours rather than days.16 The author delivered the fetus and was compelled to breastfeed it before it died a few days later. The woman also suffered vulvitis and subsequently entered a severe state of depression. Peruvian law provided for a therapeutic exception, but also imposed criminal liability on physicians who performed abortions. It was unclear whether reluctance was motivated by ideology or fear of prosecution.
Terminology and Basics
Reem S. Abu-Rustum in A Practical Guide to 3D Ultrasound, 2014
With volume sonography, it is now possible to evaluate planes not previously accessible by 2D ultrasound. In addition, depth perception is now added. The stored volumes are available for educational purposes: they can be utilized for learning anatomy, and they facilitate off-line consultation with experts and over the web. With volume sonography, it is now possible to evaluate such areas as the top of the fetal head, the fetal sutures (Figure 1.11), and the mid-sagittal plane of the fetal head (Figure 1.12). In addition, beam steering allows the visualization of previously unattainable views such as the posterior aspect of structures. As such, the level of a neural tube defect may be localized, and skeletal malformations may be characterized.
Selenium and L-carnitine protects from valproic acid-Induced oxidative stress and mitochondrial damages in rat cortical neurons
Published in Drug and Chemical Toxicology, 2022
Ahmad Salimi, Nasrin Alyan, Nasim Akbari, Zhaleh Jamali, Jalal Pourahmad
Oxidative stress has been implicated in the mechanisms of cytotoxicity and teratogenesis of VPA (Chateauvieux et al. 2010). The well-known fetal valproate syndrome, spina bifida is a neural tube defect (NTD) that results from failure of the caudal neural tube to close during organogenesis after exposure with VPA. The brain and the spinal cord develop from the neural tube through the process of neurulation during organogenesis (Tung and Winn 2011). In the current study, we chose the neonatal rats for isolation of neurons due to previous studies have been suggested that young children (less than 7.5 years) have an increased risk of toxicity of valproic acid (Star et al. 2014). Our results showed that valproic acid is toxic for isolated rat neurons up to 50 µM. Previous studies have shown that the therapeutic and toxic concentrations range for valproic acid is 40–100 and 100–200 mg/L respectively (Schulz et al. 2012). Therefore, used concentrations in this study are in therapeutic and toxic range of valproic acid (Figure 1). Interestingly, some studies have been shown neuroprotective effect of valproic acid, therefore this has a controversial effect with our results (Ximenes et al. 2015, Silva et al. 2018). However, the mentioned effect as protective have been shown in adult animals and neurodegenerative disease models, while our results obtained from in vitro models in isolated neurons.
Intellectual characteristics using WISC-IV in children with myelomeningocele
Published in Cogent Medicine, 2018
Hiroshi Mano, Kazuharu Takikawa, Nobuhiko Haga
Spina bifida is defined as a congenital condition in which posterior elements of the spine (including spinous processes and vertebral arches) are defective. Spina bifida and anencephaly comprise neural tube defects. In spina bifida cystica, a protuberance is formed due to dorsal extrusion of the spinal or cauda equina nerve. Spina bifida occulta involves only dysraphism (incomplete or abnormal fusion) of spinal posterior elements with no protrusion of meninges or neural tissue. Spina bifida cystica is especially accompanied by abnormalities, including hydrocephalus, Chiari malformations, and syringomyelia. Frequently used classifications (Bartonek, Saraste, & Knutson, 1999) of neurological-level paralysis are (Sharrard, 1964) and (Hoffer, Feiwell, & Perry et al., 1973) (the latter differs from the Hoffer classification used for ambulation abilities; see hereafter). Meanwhile, Hoffer classification (Hoffer et al., 1973) is used to evaluate ambulation abilities.
De novo frameshift mutation in YAP1 associated with bilateral uveal coloboma and microphthalmia
Published in Ophthalmic Genetics, 2022
Charles DeYoung, Bin Guan, Ehsan Ullah, Delphine Blain, Robert B. Hufnagel, Brian P. Brooks
The syndromic manifestations reported by Williamson et al. included sensorineural hearing loss, cleft lip with or without cleft palate, hematuria, and learning difficulties (21). It should be noted that a stillbirth had occurred in this family, described as an anencephalic baby with cleft lip and palate whose ocular status was unknown. Kingston et al. has raised the possibility of a neural tube defect being a part of this syndrome (24). Aside from a likely neural tube defect, our proband did not manifest any of these associated manifestations, though his hearing status and intellectual ability could not be ascertained. Also, the 13-member family described by Williamson et al. ranged in ages from age 5 to age 67 with most being adults, while our proband was only 1 at the time of evaluation (22).
Related Knowledge Centers
- Central Nervous System
- Ectoderm
- Neural Crest
- Neural Groove
- Neurulation
- Somite
- Embryo
- Spinal Cord
- Brain
- Neural Fold