Intrauterine Growth Restriction: From 1 Different Sources
(IUGR, fetal growth restriction) failure of a fetus to achieve its growth potential, resulting in the birth of a baby whose birth weight is abnormally low in relation to its gestational age (see small for gestational age). Causes include *uteroplacental insufficiency, maternal disease (e.g. infection, malnutrition, high blood pressure, smoking, and alcoholism), poor socioeconomic conditions, multiple pregnancy (e.g. twins), and fetal disease or chromosomal abnormalities. It may be associated with *preterm birth.
A popular term applied to any new formation in any part of the body. (See CANCER; CYSTS; GANGLION; TUMOUR.) For growth of children, see WEIGHT AND HEIGHT.... growth
A method of helping CONCEPTION to occur when a man is infertile (see INFERTILITY) because his sperm (see SPERMATOZOON) cannot penetrate either the cervical mucus at the entrance of the UTERUS or the barriers that surround the OVUM. The sperm, often treated chemically beforehand to increase motility, are injected directly into the uterus via the VAGINA.... intrauterine insemination
An endonuclease ENZYME, extracted from BACTERIA, that is used to cut DNA into short segments – a process essential in GENETIC ENGINEERING.... restriction enzyme
See IUD.... intrauterine contraceptive device
The increase in height and weight as a child develops. The period of most rapid growth occurs before birth. After birth, although growth is still rapid in the first few years of life, especially in the first year, the rate of
growth steadily decreases. Puberty marks another major period of growth, which continues until adult height and weight are reached, usually at about age 16–17 in girls and 19–21 in boys.
Body shape changes during childhood because different areas grow at different rates. For example, at birth, the head is already about three quarters of its adult size; it grows to almost full size during the first year. Thereafter, it becomes proportionately smaller because the body grows at a much faster rate.
Growth can be influenced by heredity and by environmental factors such as nutrition and general health. Hormones also play an important role, particularly growth hormone, thyroid hormones, and, at puberty, the sex hormones.
A chronic illness, such as cystic fibrosis, may retard growth. Even a minor illness can slow growth briefly, although the growth rate usually catches up when the child recovers. In some cases, slow growth may be the only sign that a child is ill or malnourished, in which case it is known as failure to thrive. However, short stature does not necessarily indicate poor health. Abnormally rapid growth is rare. Usually, it is a familial trait, but it may occasionally indicate an underlying disorder, such as a pituitary gland tumour causing gigantism. (See also age; child development.)... growth, childhood
a group of *growth factors that promote new bone formation. Bone morphogenic protein (BMP), a naturally occurring substance that induces *osteoblast formation, has been genetically synthesized to form bone morphogenetic protein, which stimulates new bone formation and assists with fracture healing. Other bone growth factors include a type of transforming growth factor (TGF?) and insulin-like growth factor II (IGF-II), which encourage collagen formation.... bone growth factors
(EGFR) a protein on the surface of cells (see receptor) that binds with epidermal *growth factor and is therefore involved in cell division. EGFR is expressed at increased levels in numerous tumours, particularly of the head and neck, and in colorectal cancer, in which it can be a target for antibody therapy with *cetuximab. *Tyrosine kinase inhibitors acting specifically on the EGFR include gefitinib and erlotinib in lung and pancreatic cancer.... epidermal growth factor receptor
a graph, customized to a pregnant woman’s height, weight, and other factors, that plots *fundal height and estimated fetal weight on ultrasound against weeks of gestation. The graph, which shows centile lines (see centile chart), improves prediction of a baby who is *small for gestational age.... fetal growth chart
see intrauterine growth restriction.... fetal growth restriction
see physis.... growth plate
death of a fetus in the uterus after 24 weeks of gestation. See stillbirth.... intrauterine fetal death
see IUS.... intrauterine system
(NGF) a protein (see growth factor), consisting of two polypeptide chains, that is required for the development and longevity of some neurons, including those in the sympathetic nervous system and some central nervous system and sensory neurons. Nerve growth factor is necessary for axon growth and also for initiating new neuronal connections with other cells. The role of NGFs in preventing the degeneration of brain cells is being explored in research into Alzheimer’s disease.... nerve growth factor
(PDGF) see growth factor.... platelet-derived growth factor
(TGF) a protein – a *cytokine – that controls growth, proliferation, and other functions in most cells. It plays a role in asthma and other respiratory diseases and is also involved in diseases elsewhere in the body. There are two classes: TGF-? and TGF-?.... transforming growth factor
(VEGF) a *growth factor made by both normal cells and their abnormal or malignant counterparts to stimulate new blood vessel formation (see angiogenesis). It can be targeted by a family of drugs known as *angiogenesis inhibitors, which include *bevacizumab.... vascular endothelial growth factor
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