NTD


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neural tube defect (NTD)

any of a group of congenital malformations involving defects in the skull and spinal column that are caused primarily by the failure of the neural tube to close during embryonic development. In some instances the cleft results from an abnormal increase in cerebrospinal fluid pressure on the closed neural tube during the first trimester of development. The defect may occur at any point along the neural axis or extend the entire length of the spinal column, as in holorachischisis. The amount of deformity and disability depends on the degree of neural involvement, the most severe defect being complete cranioschisis, or the total absence of the skull and defective brain development. Other cerebral dysplasias resulting from the failure of the cranial end of the neural tube to fuse are meningoencephalocele and cranial meningocele. These defects, usually accompanied by severe mental and physical disorders, occur most often in the occipital region of the skull but may also occur in the frontal or basal regions. Most neural tube malformations are caused by incomplete fusion of one or more laminae of the vertebral column, with varying degrees of tissue protrusion and neural involvement. The two most common NTDs are spina bifida and anencephaly. Other NTDs include rachischisis, myelocele, myelomeningocele, and meningocele. In all of these conditions there is constant risk of rupture of the saclike protrusion and danger of meningeal infection. Often immediate surgical repair is necessary. Adequate folate levels during the first month after conception are important in preventing neural tube defects; the U.S. Public Health Service recommends that all women of childbearing age increase their folate intake to 400 mg per day. Many of the major neural tube defects can be determined prenatally by ultrasonic scanning of the uterus and by tests for the presence of elevated concentrations of alpha-fetoprotein levels in the amniotic fluid. Such diagnostic tests are preferably performed during the 14th to 16th week of gestation so that termination of the pregnancy is possible. See also anencephaly, Arnold-Chiari malformation, spina bifida cystica.

NTD

Neural tube defect, see there.
References in periodicals archive ?
Some women may be at a higher risk of having a baby with an NTD and should consult with their GP first about whether the need a higher dose of folic acid.
Jo Walters and Paul Laidler of NTD > at the Ponteland Eco office
19,21,22] Earlier studies of siblings of individuals with NTDs failed to demonstrate an increased risk of other malformations; [2,12,23] however, more recent studies have found significant increases in the occurrence of apparently unassociated congenital abnormalities in siblings, with a variety of malformations being recorded, particularly in siblings of NTD patients with high spina bifida lesions.
The dietary and culinary principles inherent in it, such as the quest for harmony between human beings and nature, are reflections of traditional Chinese philosophy," said Zhong Lee, president of NTD.
Eisai is committed to taking proactive steps to address issues related to access to medicines, including NTDs, in accordance with established policy as it expands its business in both emerging and developing nations in this era of great globalization.
Leveraging the financial facilities, regional experiences, and replicability potential of the IDB, the technical expertise of PAHO, and the advocacy and fundraising resources of the Global Network, the LAC NTD Initiative has established a regional agenda to address the treatment gap for those afflicted by NTDs, such as indigenous groups, rural communities, the elderly, and women and children.
Once the data have been compiled, geographical information systems (GIS) simultaneously manage and display the data and include estimates of such variables as temperature, vegetation, and humidity, which affect NTD distribution.
The result of the case study indicates that the total cost is NTD 110,786,400 per year (about USD 3,632,340), and that three DCs are to be established near Keelung, Changhua, and Kaohsiung in northern, central, and southern Taiwan respectively.
The three groups were composed as follows: 95 women with a pregnancy affected by a NTD (mean age 27 years) and 265 controls with a normal pregnancy (mean age 28 years); 107 women who had had a previous pregnancy affected by an NTD but were pregnant again with an unaffected pregnancy (mean age 32 years) and 414 controls (mean age 28 years); 76 women during an affected pregnancy (mean age 27 years); and 222 controls (mean age 28 years).
The Star NTD reduces the number of conveyors by one-third, providing simplified machine cleaning, weight reduction, and lower operational costs.
It reviews state regulations regarding NTDs, then summarizes the types of NTD streams that are currently regulated under various general and individual permits in US states.
Chorion, which owns and manages classic and contemporary literary-based brands, has awarded licences to Briefly Stated, ES Originals, Freeze and NTD Apparel to allow them to produce clothing and accessories for children using Roger Hargreaves' Mr Men and Little Miss franchise.