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Anencephaly

Anencephaly is an open neural tube defect, meaning that part of the neural tube does not properly close or that it has reopened during early embryogenesis. An embryo with anencephaly develops without the top of the skull, but retains a partial skull, including the face. Anencephaly is one of the most common birth defects of the neural tube, occurring at a rate of approximately one in one thousand human pregnancies. The condition can be caused by environmental exposure to chemicals, dietary deficiencies, or genetic mutations.

Format: Articles

Subject: Disorders, Reproduction

Angelman Syndrome

Angelman syndrome is a disorder in humans that causes neurological symptoms such as lack of speech, jerky movements, and insomnia. A human cell has two copies of twenty-three chromosomes for a total of forty-six-one copy from its mother and one from its father. But in the case of Angelman syndrome, the maternal chromosome numbered 15 has a mutation or deletion in its DNA and a gene on the paternal chromosome 15 is inactivated in some parts the brain. The result is the paternal gene is silenced during development of the sperm, which is called genetic imprinting.

Format: Articles

Subject: Disorders

Cocaine as a Teratogen

Cocaine use by pregnant women has a variety of effects on the embryo and fetus, ranging from various gastro-intestinal and cardiac defects to tissue death from insufficient blood supply. Thus, cocaine has been termed a teratogen, or an agent that causes defects in fetuses during prenatal development. Cocaine is one of the most commonly used drugs in the US and it has a history of both medical and illegal recreational use. It is a drug capable of a wide array of effects on physical and mental health.

Format: Articles

Subject: Reproduction, Disorders

Neonatal Jaundice

Neonatal jaundice is the yellow discoloration of the skin and eyes due to elevated bilirubin levels in the bloodstream of a newborn. Bilirubin is a byproduct of the breakdown of red blood cells. Jaundiced infants are unable to process bilirubin at a normal rate or they have an abnormally high amount of bilirubin in their bloodstream, resulting in a buildup of the yellow colored bilirubin. That build up is called hyperbilirubinemia and is the cause of jaundice.

Format: Articles

Subject: Disorders

Ectopic Pregnancy

Many difficulties can arise with a pregnancy even after the sperm successfully fertilizes the oocyte. A major problem occurs if the fertilized egg tries to implant before reaching its normal implantation site, the uterus. An ectopic pregnancy occurs when a fertilized egg implants anywhere other than in the uterus, most commonly in the fallopian tubes. Ectopic pregnancies cannot continue to term, so a physician must remove the developing embryo as early as possible.

Format: Articles

Subject: Disorders, Processes, Reproduction

Fetal Alcohol Syndrome (FAS)

The concept Fetal Alcohol Syndrome (FAS) refers to a set of birth defects that occur in children born to mothers who abused alcohol during pregnancy. The alcohol-induced defects include pre- and post-natal growth deficiencies, minor facial abnormalities, and damage to the developing central nervous system (CNS).

Format: Articles

Subject: Disorders

Congenital Rubella Syndrome (CRS)

Congenital rubella syndrome (CRS) can occur in children whose mothers contracted the rubella virus, sometimes called German measles, during pregnancy. Depending on the gestational period when the mother contracts rubella, an infant born with CRS may be unaffected by the virus or it may have severe developmental defects. The most severe effects of the virus on fetal development occur when the mother contracts rubella between conception and the first trimester.

Format: Articles

Subject: Disorders

"The Familial Factor in Toxemia of Pregnancy" (1968), by Leon C. Chesley, et al.

In the 1950s and 1960s, researchers Leon Chesley, John Annitto, and Robert Cosgrove investigated the possible familial factor for the conditions of preeclampsia and eclampsia in pregnant women. Preeclampsia and eclampsia, which are related to high blood pressure, have unknown causes and affect at least five percent of all pregnancies.

Format: Articles

Subject: Reproduction, Experiments, Disorders

Dandy-Walker Syndrome

Dandy-Walker Syndrome is a congenital brain defect in humans characterized by malformations to the cerebellum, the part of the brain that controls movement, and to the ventricles, the fluid-filled cavities that surround the cerebellum. The syndrome is named for physicians Walter Dandy and Arthur Walker who described associated signs and symptoms of the syndrome in the 1900s. The malformations often develop during embryonic stages.

Format: Articles

Subject: Disorders

The Discovery of Fetal Alcohol Syndrome

The term Fetal Alcohol Syndrome (FAS) was first published in 1973 in an article published in the British medical journal The Lancet. In that article, a group of pediatricians and psychiatrists at the University of Washington Medical School helped to define the morphological defects and developmental delays that can affect children born to alcoholic mothers. Those observations include pre- and post-natal growth deficiencies, minor facial abnormalities, and damage to the developing brain that can result in behavioral, learning, and cognitive abnormalities.

Format: Articles

Subject: Disorders, Reproduction

Parasitic Twins

Parasitic twins, a specific type of conjoined twins, occurs when one twin ceases development during gestation and becomes vestigial to the fully formed dominant twin, called the autositic twin. The underdeveloped twin is called parasitic because it is only partially formed, is not functional, or is wholly dependent on the autositic twin.

Format: Articles

Subject: Disorders, Reproduction

Twin-to-Twin Transfusion Syndrome

Twin-to-Twin Transfusion Syndrome (TTTS) is a rare placental disease that can occur at any time during pregnancy involving identical twins. TTTS occurs when there is an unequal distribution of placental blood vessels between fetuses, which leads to a disproportionate supply of blood delivered. This unequal allocation of blood leads to developmental problems in both fetuses that can range in severity depending on the type, direction, and number of interconnected blood vessels.

Format: Articles

Subject: Disorders, Reproduction

William Thornton Mustard (1914-1987)

William Thornton Mustard was a surgeon in Canada during the twentieth century who developed surgical techniques to treat children who had congenital heart defects. Mustard has two surgeries named after him, both of which he helped to develop. The first of these surgeries replaces damaged or paralyzed muscles in individuals who have polio, a virus that can cause paralysis. The other technique corrects a condition called the transposition of the great arteries (TGA) that is noticed at birth.

Format: Articles

Subject: People, Disorders, Disorders

Role of Sonic Hedgehog (Shh) in Alcohol-Induced Craniofacial Abnormalities

Prenatal exposure to alcohol (ethanol) results in a continuum of physical and neurological developmental abnormalities that vary depending on the timing, duration, and degree of alcohol exposure. Heavy exposure during development may lead to the condition Fetal Alcohol Syndrome (FAS), characterized by growth deficits, neurological deficiencies and minor facial abnormalities. Alcohol is a known teratogen, an agent that causes birth defects and acts upon developing embryos through mechanisms that are not yet fully understood.

Format: Articles

Subject: Disorders

Teratomas

Teratomas are embryonal tumors that normally arise from germ cells and are typically benign. They are defined as being composed either of tissues that are foreign to the area in which they form, or of tissues that derive from all three of the germ layers. Malignant teratomas are known as teratocarcinomas; these cancerous growths have played a pivotal role in the discovery of stem cells. "Teratoma" is Greek for "monstrous tumor"; these tumors were so named because they sometimes contain hair, teeth, bone, neurons, and even eyes.

Format: Articles

Subject: Processes, Disorders

Studies of Thalidomide's Effects on Rodent Embryos from 1962-2008

Thalidomide is a sedative drug introduced to European markets on 1 October 1957 after extensive testing on rodent embryos to ensure its safety. Early laboratory tests in rodent populations showed that pregnant rodents could safely use it, so doctors prescribed Thalidomide to treat morning sickness in pregnant women. However, in humans Thalidomide interfered with embryonic and fetal development in ways not observed in rodent tests.

Format: Articles

Subject: Organisms, Reproduction, Disorders

Retinoids As Teratogens

Vitamin A (retinol) is an essential vitamin in the daily functioning of human beings that helps regulate cellular differentiation of epithelial tissue. Studies have shown that an excess of vitamin A can affect embryonic development and result in teratogenesis, or the production of birth defects in a developing embryo. Excess intake of vitamin A and retinoids by pregnant women often results malformations to fetuses' skulls, faces, limbs, eyes, central nervous system.

Format: Articles

Subject: Disorders, Reproduction

Teratogens

Teratogens are substances that may produce physical or functional defects in the human embryo or fetus after the pregnant woman is exposed to the substance. Alcohol and cocaine are examples of such substances. Exposure to the teratogen affects the fetus or embryo in a variety of ways, such as the duration of exposure, the amount of teratogenic substance, and the stage of development the embryo or fetus is in during the exposure.

Format: Articles

Subject: Disorders

Early Infantile Autism and the Refrigerator Mother Theory (1943-1970)

In 1943, child psychiatrist Leo Kanner in the US gave the first account of Early Infantile Autism that encouraged psychiatrists to investigate what they called emotionally cold mothers, or refrigerator mothers. In 1949, Kanner published Problems of Nosology and Psychodynamics of Early Infantile Autism. In that article, Kanner described autistic children as reared in emotional refrigerators. US child psychiatrists claimed that some psychological or behavioral conditions might have origins in emotional or mental stress, meaning that they might be psychogenic.

Format: Articles

Subject: Disorders, Theories

Neonatal Respiratory Distress Syndrome and Its Treatment with Artificial Surfactant

Neonatal respiratory distress syndrome, previously called hyaline membrane disease, is a respiratory disease affecting premature newborns. Neonatal respiratory distress syndrome involves shallow breathing, pauses between breaths that last a few seconds, or apnea, and a bluish tinge to the infant’s skin. The syndrome occurs when microscopic sacs called alveoli in infant lungs do not produce surfactant, a liquid that coats the inside of the lungs and helps them inflate during breathing.

Format: Articles

Subject: Disorders

Fetal Surgery

Fetal surgeries are a range of medical interventions performed in utero on the developing fetus of a pregnant woman to treat a number of congenital abnormalities. The first documented fetal surgical procedure occurred in 1963 in Auckland, New Zealand when A. William Liley treated fetal hemolytic anemia, or Rh disease, with a blood transfusion.

Format: Articles

Subject: Disorders, Ethics, Reproduction

The Mustard Operation

The Mustard Operation is a surgical technique to correct a heart condition called the transposition of the great arteries (TGA). TGA is a birth defect in which the placement of the two arteries, the pulmonary artery, which supplies deoxygenated blood to the lungs, and the aorta, which takes oxygenated blood to the body are switched. William Thornton Mustard developed the operation later named for him and in 1963 operated on an infant with TGA, and ameliorated the condition, at the Hospital for Sick Children in Toronto, Canada.

Format: Articles

Subject: Technologies, Disorders

US Endocrine Disruptor Screening Program

In 1996, the US Congress mandated that the US Environmental Protection Agency (EPA) create and regulate the Endocrine Disruptor Screening Program. The program tests industrial and agricultural chemicals for hormonal impacts in humans and in wildlife that may disrupt organisms' endocrine systems. The endocrine system regulates the release of small amounts of chemical substances called hormones to keep the body functioning normally.

Format: Articles

Subject: Disorders, Legal, Ethics

Transposition of the Great Arteries (TGA)

Transposition of the great arteries or TGA is a potentially fatal congenital heart malformation where the pulmonary artery and the aorta are switched. The switch means that the aorta, which normally carries oxygenated blood, carries deoxygenated blood. There are two types of the malformation, d-TGA where no oxygen reaches the body and l-TGA where some oxygenated blood circulates. In the US, the Centers for Disease Control estimate that about 1,901 infants are born each year with TGA, or about one for every 2,000 births.

Format: Articles

Subject: Disorders

Tay-Sachs Disease

In 1881 British opthalmologist Warren Tay made an unusual observation. He reported a cherry-red spot on the retina of a one-year-old patient, a patient who was also showing signs of progressive degeneration of the central nervous system as manifested in the child's physical and mental retardation. This cherry-red spot is a characteristic that would eventually come to be associated with metabolic neurological disorders like Sandhoff, GM-1, Niemann-Pick, and, to the credit of Tay, the lysosomal storage disorder known as Tay-Sachs disease.

Format: Articles

Subject: Disorders