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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

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

VACTERL Association

VACTERL association is a term applied to a specific group of abnormalities involving structures derived from the mesoderm. Although the defects of this disorder are clearly linked, VACTERL is called an association rather than a syndrome because the exact genetic cause is unknown. "VACTERL" is an acronym, each letter standing for one of the defects associated with the condition: V for vertebral anomalies, A for anal atresia, C for cardiovascular anomalies, T for tracheoesophageal fistula, E for esophageal atresia, R for renal anomalies, and L for limb defects.

Format: Articles

Subject: Disorders

The Effects of Diethylstilbestrol on Embryonic Development

Estrogen plays a key role in the regulation of gene transcription. This is accomplished by its ability to act as a ligand and to bind to specific estrogen receptor (ER) molecules, such as ERα and ERβ, which act as nuclear transcription factors. There are three major nuclear estrogen receptor protein domains: the estrogen binding domain, the protein interaction domain, and the DNA binding domain.

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

Trisomy 18 (Edwards Syndrome)

John Hilton Edwards first described the symptoms of the genetic disorder known as Trisomy 18 - one of the most common forms of trisomy, which occurs when cells have an extra copy of a chromosome, in humans - in 1960. Trisomy 18, also known as Edwards Syndrome, occurs approximately once per 6000 live births and is second in frequency only to Trisomy 21, or Down's Syndrome, as an autosomal trisomy. Trisomy 18 causes substantial developmental problems in utero.

Format: Articles

Subject: Disorders

Niemann-Pick Disease

In 1914 Albert Niemann, a German pediatrician who primarily studied infant metabolism, published a description of an Ashkenazi Jewish infant with jaundice, nervous system and brain impairments, swollen lymph nodes (lymphadenopathy), and an enlarged liver and spleen (hepatosplenomegaly). He reported that these anatomical disturbances resulted in the premature death of the child at the age of eighteen months. After extensively studying the abnormal characteristics of the infant, Niemann came to the conclusion that the disease was a variant of Gaucher's disease.

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

"'Doing the Month': Confinement and Convalescence of Chinese Women After Childbirth" (1978), by Barbara L.K. Pillsbury

In 1978 Social Science and Medicine published Barbara L.K. Pillsbury's article, 'Doing the Month': Confinement and Convalescence of Chinese Women After Childbirth, which summarized the results of Pillsbury's study on Chinese childbirth customs. Pillsbury, a professor of cultural anthropology at San Diego State University in San Diego, California, conducted over eighty interviews with people in Taiwan and China, including civilians, herbalists, and physicians over a four-month period in 1975.

Format: Articles

Subject: Publications

The Roslin Institute (1993- )

The Roslin Institute was established in 1993 in the village of Roslin, Scotland, as an independent research center by the Biotechnology and Biological Sciences Research Council (BBSRC), and as of 2014 is part of the University of Edinburgh in Edinburgh, Scotland. Researchers at the Roslin Institute cloned the Dolly the sheep in 1996. According to the Roslin Institute, Dolly was the first mammal to develop into an adult from the transfer of the nucleus of an adult sheep cell into an ovum with the nucleus removed.

Format: Articles

Subject: Organizations

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

Diprosopus (Craniofacial Duplication)

Diprosopus is a congenital defect also known as craniofacial duplication. The exact description of diprosopus refers to a fetus with a single trunk, normal limbs, and facial features that are duplicated to a certain degree. A less severe instance is when the nose is duplicated and the eyes are spaced far apart. In the most extreme instances, the entire face is duplicated, hence the name diprosopus, which is Greek for two-faced. Fetuses with diprosopus often also lack brains (anencephaly), have neural tube defects, or heart malformations.

Format: Articles

Subject: Disorders, Reproduction

Neural Tube Defects (NTD): Folic Acid and Pregnancy

In the US, one in 1000 births is affected by neural tube defects (NTD). A neural tube defect is a birth defect involving the malformation of body features associated with the brain and spinal cord. An NTD originates from and is characterized by incomplete closure of the neural tube, which is an organizer and precursor of the central nervous system.

Format: Articles

Subject: Disorders, Reproduction

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

Isotretinoin (Accutane) as a Teratogen

Isotretinoin is a molecule and a byproduct (metabolite) of vitamin A, and in greater than normal amounts in pregnant women, it can cause fetal abnormalities including cleft lips, ear and eye defects, and mental retardation. Isotretinoin is commonly called by its trade name Accutane, and it's a chemical compound derived from vitamin A, or retinoic acid. Doctors prescribe isotretinoin to treat severe acne. For pregnant women, too much vitamin A or isotretinoin can also cause greater than normal rates of stillbirths and fetal disintegrations after the ninth week of gestation.

Format: Articles

Subject: Reproduction, Disorders

Conjoined Twins

Conjoined twins are twins whose bodies are anatomically joined in utero. The degree to which the twins are attached can range from simple, involving skin and cartilage, to complex, including fusion of the skull(s), brain(s), or other vital organs. There are more than a dozen classifications of conjoined twins but what they all tend to have in common is the sharing of the chorion, placenta, and amniotic sac.

Format: Articles

Subject: Disorders, Reproduction

Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) Gene

The Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) gene was identified in 1989 by geneticist Lap-Chee Tsui and his research team as the gene associated with cystic fibrosis (CF). Tsui's research pinpointed the gene, some mutations to which cause CF, and it revealed the underlying disease mechanism. The CFTR gene encodes a protein in the cell membrane in epithelial tissues and affects multiple organ systems in the human body. Mutations in the CFTR gene cause dysfunctional regulation of cell electrolytes and water content.

Format: Articles

Subject: Disorders, Reproduction

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

Effects of Prenatal Alcohol Exposure on Basal Ganglia Development

Prenatal exposure to alcohol (ethanol) in human and animal models results in a range of alcohol-induced developmental defects. In humans, those collective birth defects are called Fetal Alcohol Spectrum Disorders, with the most severe manifestation being Fetal Alcohol Syndrome (FAS). FAS is defined by pre- and post-natal growth retardation, minor facial abnormalities, and deficiencies in the central nervous system (CNS). The basal ganglia, one of the central nervous system components, are affected by exposure to ethanol during development.

Format: Articles

Subject: Disorders, Reproduction

Methylmercury and Human Embryonic Development

Methylmercury (MeHg) is an organic form of mercury that can damage the developing brains of human fetuses. Women who consume methylmercury during pregnancy can bear children who have neurological issues because methylmercury has toxic effects on the nervous system during embryonic development. During the third week of gestation, the human nervous system begins to form in the embryo. During this gestational period, the embryo's nervous system is particularly susceptible to the influence of neurotoxins like methylmercury that can result in abnormalities.

Format: Articles

Subject: Reproduction, Disorders

The Effects of Bisphenol A on Embryonic Development

Bisphenol A (BPA) is an organic compound that was first synthesized by Aleksandr Dianin, a Russian chemist from St. Petersburg, in 1891. The chemical nomenclature of BPA is 2,2-bis (4-hydroxyphenyl) propane. The significance of this synthesized compound did not receive much attention until 1936, when two biochemists interested in endocrinology, Edward Dodds and William Lawson, discovered its ability to act as an estrogen agonist in ovariectomized, estrogen-deficient rats.

Format: Articles

Subject: Disorders, Reproduction

Effects of Prenatal Alcohol Exposure on Central Nervous System Development

Prenatal exposure to alcohol (ethanol) results in a continuum of physical, neurological, behavioral, and learning defects collectively grouped under the heading Fetal Alcohol Spectrum Disorder (FASD). Fetal Alcohol Syndrome (FAS) is part of this group and was first defined in 1973 as a condition characterized by pre- and postnatal growth deficiencies, facial abnormalities and defects of the central nervous system (CNS). The CNS is particularly vulnerable to the effects of ethanol during prenatal development.

Format: Articles

Subject: Disorders, Reproduction

Mitochondrial Diseases in Humans

Mitochondrial diseases in humans result when the small organelles called mitochondria, which exist in all human cells, fail to function normally. The mitochondria contain their own mitochondrial DNA (mtDNA) separate from the cell's nuclear DNA (nDNA). The main function of mitochondria is to produce energy for the cell. They also function in a diverse set of mechanisms such as calcium hemostasis, cell signaling, regulation of programmed cell death (apoptosis), and biosynthesis of heme proteins that carry oxygen.

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

Effect of Prenatal Alcohol Exposure on Radial Glial Cells

Prenatal alcohol (ethanol) exposure can have dramatic effects on the development of the central nervous system (CNS), including morphological abnormalities and an overall reduction in white matter of the brain. The impact of ethanol on neural stem cells such as radial glia (RG) has proven to be a significant cause of these defects, interfering with the creation and migration of neurons and glial cells during development.

Format: Articles

Subject: Disorders, Reproduction