Agreement, arbitration: See: Arbitration agreement.
Friday, July 10, 2009
Definition of Agranulocytosis, infantile genetic
Agranulocytosis, infantile genetic: Children born with this condition lack neutrophils (a type of white blood cell that is important in fighting infection). These children suffer frequent infections from bacteria which in the past led to death in three-quarters of cases before 3 years of age. This disease is also known as severe congenital neutropenia (SCN).
Children with SCN have no special problems with viral or fungal infections. They do, however, have an increased risk of developing acute myelogenous leukemia or myelodysplasia, a bone marrow disorder. Aside from agranulocytosis, the bone marrow and blood show a number of other abnormalities (including maturational arrest of neutrophil precursors at the promyelocyte stage, absolute monocytosis, eosinophilia and thrombocytosis). The gamma globulin level in blood is low.
The inheritance of the disease is autosomal recessive. Both seemingly-normal parents carry an SCN gene while each of their children, boys and girls alike, has a 1 in 4 (25%) risk of receiving both SCN genes and having the disease: severe congenital neutropenia (SCN).
SCN was first clearly described by Kostmann in 1956. It is now known to be caused by a defect in a gene on chromosome 1 (in 1p35-p34.3) that codes for what is called the granulocyte colony-stimulating factor receptor (GCSFR).
Treatment with recombinant human granulocyte colony-stimulating factor (GCSF) elevates the granulocyte counts, helps resolve preexisting infections, diminishes the number of new infections and results in significant improvements in survival and quality of life. Some patients have developed leukemia or myelodysplastic syndrome following treatment with GCSF.
Congenital neutropenia is due to diverse causes. Not all patients with congenital neutropenia have mutations in the GCSFR gene.
Alternative names for severe congenital neutropenia (SCN) include: Kostmann's disease or syndrome, infantile genetic agranulocytosis and genetic infantile agranulocytosis.
Children with SCN have no special problems with viral or fungal infections. They do, however, have an increased risk of developing acute myelogenous leukemia or myelodysplasia, a bone marrow disorder. Aside from agranulocytosis, the bone marrow and blood show a number of other abnormalities (including maturational arrest of neutrophil precursors at the promyelocyte stage, absolute monocytosis, eosinophilia and thrombocytosis). The gamma globulin level in blood is low.
The inheritance of the disease is autosomal recessive. Both seemingly-normal parents carry an SCN gene while each of their children, boys and girls alike, has a 1 in 4 (25%) risk of receiving both SCN genes and having the disease: severe congenital neutropenia (SCN).
SCN was first clearly described by Kostmann in 1956. It is now known to be caused by a defect in a gene on chromosome 1 (in 1p35-p34.3) that codes for what is called the granulocyte colony-stimulating factor receptor (GCSFR).
Treatment with recombinant human granulocyte colony-stimulating factor (GCSF) elevates the granulocyte counts, helps resolve preexisting infections, diminishes the number of new infections and results in significant improvements in survival and quality of life. Some patients have developed leukemia or myelodysplastic syndrome following treatment with GCSF.
Congenital neutropenia is due to diverse causes. Not all patients with congenital neutropenia have mutations in the GCSFR gene.
Alternative names for severe congenital neutropenia (SCN) include: Kostmann's disease or syndrome, infantile genetic agranulocytosis and genetic infantile agranulocytosis.
Definition of Agranulocytosis
Agranulocytosis: A marked decrease in the number of granulocytes. Granulocytes are a type of white blood cell filled with microscopic granules that are little sacs containing enzymes that digest microorganisms.
Granulocytes are part of the innate, somewhat non specific infection-fighting immune system. They do not respond exclusively to specific antigens, as do B-cells and T-cells.
Agranulocytosis results in a syndrome of frequent chronic bacterial infections of the skin, lungs, throat, etc. Although "agranulocytosis" literally means no granulocytes, there may, in fact, be some granulocytes but too few of them, i.e. granulocytopenia. Agranulocytosis can be genetic and inherited or it can be acquired as, for example, an aspect of leukemia.
Neutrophils, eosinophils and basophils are all types of granulocytes. They are named by the staining features of their granules in the laboratory:
Neutrophils have "neutral" subtle granules; Eosinophils have prominent granules that stain readily with the acid dye eosin; and
Basophils have prominent granules that stain readily basic (non acidic) dyes.
This classification dates back to a time when certain structures could be identified in cells by histochemistry, but the functions of these intracellular structures were still not yet fathomed. However, the classification of granulocytes into neutrophils, eosinophils and basophils is still widely used (and quite useful).
Granulocytes are part of the innate, somewhat non specific infection-fighting immune system. They do not respond exclusively to specific antigens, as do B-cells and T-cells.
Agranulocytosis results in a syndrome of frequent chronic bacterial infections of the skin, lungs, throat, etc. Although "agranulocytosis" literally means no granulocytes, there may, in fact, be some granulocytes but too few of them, i.e. granulocytopenia. Agranulocytosis can be genetic and inherited or it can be acquired as, for example, an aspect of leukemia.
Neutrophils, eosinophils and basophils are all types of granulocytes. They are named by the staining features of their granules in the laboratory:
Neutrophils have "neutral" subtle granules; Eosinophils have prominent granules that stain readily with the acid dye eosin; and
Basophils have prominent granules that stain readily basic (non acidic) dyes.
This classification dates back to a time when certain structures could be identified in cells by histochemistry, but the functions of these intracellular structures were still not yet fathomed. However, the classification of granulocytes into neutrophils, eosinophils and basophils is still widely used (and quite useful).
Thursday, July 9, 2009
Definition of Agonist maintenance treatment
Agonist maintenance treatment: See: Methadone treatment program.
Definition of Agnate
Agnate: 1. As a noun, a relative on the father's side.
2. As an adjective, related on the father's side.
As opposed to enate (someone related on the mother's side) From the Latin agnatus, the past participle of agnasci (to issue forth), from ad+ nasci (to be born).
2. As an adjective, related on the father's side.
As opposed to enate (someone related on the mother's side) From the Latin agnatus, the past participle of agnasci (to issue forth), from ad+ nasci (to be born).
Definition of Aging, National Institute on
Aging, National Institute on (NIA): One of the US National Institutes of Health (NIH). The
mission of the National Institute on Aging is to "lead a national
program of research on
the biomedical, social, and behavioral aspects of the aging
process; the prevention of age-related diseases and
disabilities; and the promotion of a better quality of life
for all older Americans."
The National Institute on Aging was founded in 1974. It is
one of two institutes of the NIH based on life stages. The other
is the National Institute of Child Health and Human Development (NICHD).
mission of the National Institute on Aging is to "lead a national
program of research on
the biomedical, social, and behavioral aspects of the aging
process; the prevention of age-related diseases and
disabilities; and the promotion of a better quality of life
for all older Americans."
The National Institute on Aging was founded in 1974. It is
one of two institutes of the NIH based on life stages. The other
is the National Institute of Child Health and Human Development (NICHD).
Definition of Aging
Aging: The process of becoming older, a process that is genetically determined and environmentally modulated.
Research into aging: To sum up the state of research into aging is well beyond the confines of this space (and this writer's talents). However, here is one type of research into the genetics of aging.
A gene has been discovered that helps determine the life-span of the fruit fly Drosophila. When the gene is mutated (altered), it can extend the life-span of fruit flies. It doubles their life-span. The gene has been named Indy (for I'm not dead yet). It appears that the protein encoded by this gene transports and recycles metabolic byproducts. Defects in the gene may lead to production of a protein that renders metabolism less efficient so that its body functions as if the fruit fly were dieting, even though its eating habits are unchanged. Mutations in Indy thus appear to create a metabolic state that mimics caloric restriction, which has been shown to extend life-span.
Reference: Rogina B, Reenan RA, Nilsen SP, and Helfand SL. Extended life-span conferred by cotransporter gene mutations in Drosophila. Science Dec 15 2000: 2137-2140.
Some useful suggestions for extending life: No known substance can halt aging or extend life, but here are some useful tips for improving the chances of living a long time and staying healthy:
Eat a balanced diet, including five helpings of fruits and vegetables a day.
Exercise regularly (check with a doctor before starting an exercise program).
Get regular health check-ups.
Don't smoke (it's never too late to quit).
Practice safety habits at home to prevent falls and fractures.
Always wear your seatbelt in a car.
Stay in contact with family and friends.
Stay active through work, play, and community.
Avoid overexposure to the sun and the cold.
If you drink, moderation is the key.
When you drink, let someone else drive.
Keep personal and financial records in order to simplify budgeting and investing.
Plan long-term housing and money needs.
Keep a positive attitude toward life.
Do things that make you happy.
Research into aging: To sum up the state of research into aging is well beyond the confines of this space (and this writer's talents). However, here is one type of research into the genetics of aging.
A gene has been discovered that helps determine the life-span of the fruit fly Drosophila. When the gene is mutated (altered), it can extend the life-span of fruit flies. It doubles their life-span. The gene has been named Indy (for I'm not dead yet). It appears that the protein encoded by this gene transports and recycles metabolic byproducts. Defects in the gene may lead to production of a protein that renders metabolism less efficient so that its body functions as if the fruit fly were dieting, even though its eating habits are unchanged. Mutations in Indy thus appear to create a metabolic state that mimics caloric restriction, which has been shown to extend life-span.
Reference: Rogina B, Reenan RA, Nilsen SP, and Helfand SL. Extended life-span conferred by cotransporter gene mutations in Drosophila. Science Dec 15 2000: 2137-2140.
Some useful suggestions for extending life: No known substance can halt aging or extend life, but here are some useful tips for improving the chances of living a long time and staying healthy:
Eat a balanced diet, including five helpings of fruits and vegetables a day.
Exercise regularly (check with a doctor before starting an exercise program).
Get regular health check-ups.
Don't smoke (it's never too late to quit).
Practice safety habits at home to prevent falls and fractures.
Always wear your seatbelt in a car.
Stay in contact with family and friends.
Stay active through work, play, and community.
Avoid overexposure to the sun and the cold.
If you drink, moderation is the key.
When you drink, let someone else drive.
Keep personal and financial records in order to simplify budgeting and investing.
Plan long-term housing and money needs.
Keep a positive attitude toward life.
Do things that make you happy.
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