 |
Web Hosting by Netfirms | Free Domain Names by Netfirms |
|
|
|
|
|
B |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Albumin : is the major plasma protein (approximately 60 per cent of the total). It is synthesized by liver. It have three main functions :
Alpha-FetoProtein (AFP) : is a glycoprotein synthesized by the fetal liver and some cancers (mainly HCC and testicular germ cell cancer). It's elevated (normal value <15 ng/ml) in:
Ammonia : is a toxic by-product of protein metabolism that is transformed in urea (non toxic) by liver cells. In advanced liver diseases there is a build-up of ammonia, due to liver dysfunction. (normal value <50 mg/dl).
Anemia : a reduced number of red blood cells in the bloodstream, resulting in insufficient delivery of oxygen to tissues and organs.
Anorexia : having little or no appetite for food.
Antibodies (or Immuneglobulins, Ig)
: are glycoproteins, produced by immune system, which bind to foreign proteins
(antigen), causing their elimination. Specific antibodies are produced after
an infection or after a vaccination and protect the body from further infections.Their
presence can be assessed with blood test to estabilish if a infecious disease
is occurred.
Antibodies can also be administered after exposure to an infectious agent
to prevent the development of the disease (passive immunization).
Antigen : is a substance which is capable of inducing a specific immune response. Antigens are present on viruses, bacteria, toxins, but also on human cells and tissues (they cause auto immune diseases).
Arthralgia : pain in one ore more joints.
AST : see transaminases.
Asymptomatic : without obvious signs or symptoms of disease.
Bile : a greenish-yellow fluid secreted by the liver and stored in the gallbladder. Bile contains cholesterol, lecithin, water, bile salts and waste products such as bilirubin and some drugs. Bile salts allow the digestion and the intestinal absorption of fats and then of fat-soluble vitamins (A, D, E and K).
Bile duct : any of the ducts by which bile is carried from the liver, first to the gallbladder and then to the duodenum (the first section of the small intestine).
Bilirubin : is a pigment produced when haemoglobin and cytochromes are destroyed. The liver trasforms it into a soluble compound (direct bilirubin) that is elimined with urine and bile. A high level of bilirubin causes yellowing of the eyes and skin, called jaundice.
Biopsy : a procedure used to obtain a small amount of tissue from a organ for microscopic analysis. Biopsy can be accomplished with a biopsy needle, passed through the skin into the organ in question, or by an open surgical incision.
Blood Cell : there are three main types of cell in the blood stream :
Budd-Chiari Syndrome : it's a rare disease characterized by occlusion of hepatic veins, usually accompanied by ascites, hepatomegaly, and pain in abdomen.
Capsid : the proteic coat that covers the genome (DNA or RNA) of a virus. The capsid is built up of subunits that self assemble in a pattern typical of a particular virus.
Carrier : an individual who hosts a virus or has a gene (or the genes) that cause a disease, withouth displaing its symptoms. A carrier however can transmit the viral disease to other person and genetic disorders to his/her offspring.
Centers for Disease Control and Prevention (CDC) : is an USA agency, responsible for estimating prevalence rates and making epidemiological studies (http://www.cdc.gov/ ).
Cholangitis : is an inflammation of bile ducts.
Cholestasis : it 's a stoppage or suppression of the flow of bile.
Chronic : a disease or a symptom that persists for a long period of time without recovers.
Complete Blood Count (CBC) : is a blood test that determines the number of red blood cells, white blood cells and platelets present in the patients.
Cryoglobulins : abnormal plasma immunoglobulins (IgG or IgM) that precipitates when serum is cooled. They cause damage to blood vessels (vasculitis) and therefore to the tissues that they fed.
Cryoglobulinemia : is a condition characterized by the presence of cryoglobulins in the blood.
DNA : Deoxyribo-Nucleic Acid (see genome).
Diagnosis : the determination of the nature of a case of disease.
Diplopia : double vision.
Diuretic : a medication that promotes the excretion of salts and water from the kidney, increasing the volume of urine produced.
Dosage : is the determination and regulation of the size, frequency and number of doses.
Drug : any animal, vegetable, or mineral substance used in the composition of medicines.
Endemic : a disease or an agent present or usually prevalent in a population or geographical area at all times.
Endoscope : a flexible viewing instrument used for inspection of any cavity of the body. It has diagnostic (e.g. biopsy) and therapeutic capabilities (e.g. esophageal varices sclerotherapy) through special channels.
Envelope : is the outer layer of some viruses (e.g. HBV). It derives from plasma membrane of the host cell.
Eosinophils : are a type of granulocytes. They destroy parasitic organisms and play a major role in allergic reactions (hypersensitivity). They also secrete chemical mediators that can cause bronchoconstriction in asthma.
Erythrocytes : see red blood cells.
Esophageal Varices : is an abnormal dilatation of the veins in the esophagus, that occurs as the result of portl hypertension due to liver cirrhosis. Varices are prone to rupture, causing a serious bleeding.
Exacerbation : an increase in the severity of a disease or of its symptoms.
False Positive : a result that is erroneously positive (abnormal) when a situation is normal.
Fatty liver (steatosis) : abnormal lipid increase in the liver. It's caused by reduced oxidation of fatty acids or decreased synthesis and release of lipoprotiens, that cause an inadequate lipid clearance from the liver.
Ferritin : is an iron storage protein found mainly in liver. It's released in blood, where it can be dosed, giving information on iron body storage. Higher than normal values can be seen in haemochromatosis.
Fibrosis : is the deposition of collagen, that forms a fibrose (scar) tissue, poor of blood vessels and of cells and that therefore impair liver function. Liver fibrosis represents the wound healing response of the liver to a long term disease that damage it. Liver fibrosis leads to cirrhosis.
Focal Lymphoid Aggregates : are nodules of lymphocytes. They are frequently found in liver biopsy of patients with chronic hepatitis C.
Food and Drug Administration (FDA) : the U.S. Agency responsible for regulation of biotechnology food products. The major laws under which the agency has regulatory powers include the Food, Drug, and Cosmetic act, and the Public Health Service Act.
Fulminant hepatitis : a severe and rapidly progressive form of hepatitis accompanied by hepatocellular death and hepatic failure.
Genome : one or more molecules of nucleid acid, called chromosomes, that encode the genetic informations (genes) required to determinate the structure, function and behavior of a cell or of a virus. Human genome has 46 chromosomes of DNA. Viruses can have a DNA (e.g. HBV) or a RNA (e.g. HCV) genome.
Glycogen : is a branched polymer of D glucose and represents the major short term storage of glucose of animal cells and is particularly abundant in the liver and to a lesser extent in muscle.
Glycolysis : is the conversion of glucose to pyruvate, with production of energy (2 molecule of ATP). The glycolytic pathway takes place in the cytosol of cells.
Granulocytes : are a type of white blood cells with numerous cytoplasmic granules. They are subdivided, according to the staining properties of the granules, into eosinophils, basophils and neutrophils.
Hemoglobin (or haemoglobin) : is the oxygen carrying protein found in red blood cells. A low concentration of hemoglobin in blood is called anemia.
Hepatic : pertaining to the liver.
Hepatic Stellate Cells (or Ito cells) : reside in the space of Disse and in normal liver are the major storage site of vitamin A. When a chronic liver injury occurs (e.g. a chronic hepatitis), these cells start produce collagen and other extracellular matrix proteins, that lead to liver fibrosis and then to cirrhosis.
Hepatitis : is an inflammation of the liver, that can be caused by viruses, bacteria, drugs or toxins. If persist for more than 6 months is called chronic hepatitis.
Hepatic encephalopathy: is a serious complication of advanced liver disease caused by toxins, that the liver is no more able to remove from the bloodstream. It is clinically manifested by personality changes and impaired intellectual ability, awareness, and neuromuscular functioning.
Hepatologist : is a physican who specializes in the liver and its diseases.
Hepatorenal syndrome : a combined liver and kidney failure.
Hepatotoxic : a compound that is toxic to liver cells.
Histology : the study of cells and tissue structure on the microscopic level. The study is performed on small amount of tissue obtained with a biopsy.
Human Leukocyte Antigen (HLA) : is the human Major Histocompatibility Complex (MHC).
Immunoglobulin (or Ig) : see antibodies.
Incubation period : is the amount of time that elapses between infection and the development of symptoms. It varies for the different hepatitis viruses.
Infection : is the invasion and multiplication of microorganisms in body tissues, which may be clinically unapparent or result in the development of a disease.
Inflammation : a localized protective response induced by injury or destruction of tissues. It is characterised in the acute form by the classical signs of pain, heat, redness, swelling and loss of function. Histologically, it's characterized by dilatation of arterioles, capillaries and venules, with increased permeability and blood flow (cause heat and redness), exudation of fluids, including plasma proteins and leucocytic migration into the inflammatory focus (cause pain, swelling and loss of function).
Intrahepatic : within the liver.
IVDU : Intravenous drug use.
Kuppfer Cells : are specialised macrophage of the liver sinusoids. They are part of the reticuloendothelial system.
Lethargy : abnormal drowsiness or stupor, a condition of indifference.
Leukocytes (or white blood cells) : blood cells that fight infections and other diseases. They can be found in blood and lymphatic system. There are three types of leukocytes : granulocytes, lymphocytes and monocytes.
Lymphadenopathy : a swelling of the lymph nodes.
Lymphocytes : are a type of white blood cells that fight infection with high specificity. There are 2 types of these cells (see B-Lymphocytes and T-Lymphocytes).
Lymphocytopenia : an abnormally low number of lymphocytes in the blood. This condition characterized by an increased risk of infetion.
Major Histocompatibility Complex (MHC) : is a complex family of genetically inherited proteins that play a critical role in immune response to foreign organisms. It is also involved in autoimmune disease and in transplant rejection. MHC are located on cell surface and work like receptors, that interact with immune cells. In mammals there are 2 classes of MHC :
Monocytes : one of three types of white blood cells. Monocytes can exit from blood vessels and reach the tissues, where they evolve into macrophages.
Mononuclear cells : are leucocytes other than polymorphonuclear cells. They include lymphocytes.
Myalgia : pain in one or more muscles.
Myoglobin : is a oxygen store protein found in muscles.
Needlestick Injury : penetrating stab wounds caused by a needle. It can cause the transmission of blood-borne pathogens.
Neutrophils : are a type of granulocytes. They are phagocyte and are increased when a bacterial infection occurs.
Nonsteroidal Anti-Inflammatory Drugs (NSAIDs) : are commonly used drugs with anti-inflammatory, fever-reducing, and pain-relieving properties. They works by inhibiting cyclooxygenase, an enzyme responsible for making prostaglandins.
Nucleus : is the major organelle of eukaryotic cells. It contains the cell genome (chromosomes), that is separated from the cytoplasm by the nuclear envelope.
Nuclear Envelope : a membrane system that surrounds the nucleus of eukaryotic cells. Consists of inner and outer membranes, separated by perinuclear space and perforated by nuclear pores.
Oncogene : a gene that induces cancer. It can be a gene of a normal cell that becomes alterated (see proto-oncogene), or derives from a virus (viral oncogene) that infects a normal cell.
Oncogenic : an event or a cause that induces cancer.
Opportunistic infections: are infections that occur in persons with weak immune systems due to AIDS, cancer or immunosuppressive drugs such as corticosteroids or chemotherapy.
Parenchyma : the essential elements of an organ, used in anatomical nomenclature as a general term to designate the functional elements of an organ, as distinguished from its framework or stroma.
Pathogenesis : the origin and development of a disease.
PCR (Polymerase Chain Reaction) : it's a technique used to amplificate DNA. Also RNA can be amplificate, but it must be first transformed into RNA. A test based on PCR is very sensitive and is used to detect the presence and the amount of DNA or RNA of a specific organism (e.g. a virus) in the blood or tissue.
Phagocyte : a cell that is capable of phagocytosis (eat foreign particles or other cells). The main mammalian phagocytes are neutrophils and macrophages.
Pharmacocynetic : is the study of the time courses of absorption, distribution and elimination of drugs.
Plasma : is the fluid in which blood cells are suspended. It contains many important proteins such albumin, clotting factors, immunoglobulins, and complements.
Plasma Cells : are specialized white blood cells that produce antibodies. They derives from B-lymphocytes.
Platelets : a particle found in the bloodstream that binds to fibrinogen at the site of a wound to begin the blood clotting process. Platelets are formed in bone marrow, where they arise from cells called megakaryocytes.
Portal hypertension : a portal venous pression greater than 20 mmHg. It causes splenomegaly (spleen enlargement), esophageal varices and ascites.
Portal vein : is a large vein that carries blood from the spleen, pancreas, stomach and intestines to the liver.
Prevalence : is the proportion of individuals in a population having a disease.
Prognosis : is the probable outcome of a disease.
Prophylactic : preventive measure or medication.
Protease Inhibitors : these drugs block the ability of the viral protease to cleave the finished viral polypeptide sequence into the smaller functional enzymes, thus interfering with further production of viruses. This is the newest group of HIV drugs available on the market (saquinavir and ritonavir). Protease inhibitors specific for HCV are under study.
Proto-oncogene : a normal cellular gene that is activated to become an oncogene by mutation, deletion, rearrangement over expression or inappropriate expression.
Quasispecies : the genetic heterogeneity of viral population within an infected individual.
Resection : removal of a portion or all of an organ or other structure.
Ribavirin : is an antiviral drug (is a nucleoside analogue) active against respiratory syncytial virus and hepatitis C virus (HCV).
Risk factors : are an aspect of personal behaviour or lifestyle, environmental exposure, or inborn or inherited characteristic, which, on the basis of epidemiologic evidence, is known to be associated with a health-related condition.
RNA : Ribo-Nucleic Acid. Plays a role in transferring information from DNA to the protein-forming system of the cell. Some viruses, like HCV, have a genome of RNA.
Sepsis : is the presence of organisms in the blood.
Sequelae : is a condition following as a consequence of a disease.
SGOT : see transaminases.
SGPT : see transaminases.
Sign : is the objective evidence of a disease, perceptible to the examining physician.
Splenomegaly : enlargement of the spleen. It can be a sign of portal hypertension.
Steatosis (fatty liver) : abnormal lipid increase in the liver.
Subcutaneous Injection : the delivery of a medication into the subcutaneous tissues via injection.
Symptom : is the subjective evidence of disease perceived by the patient (symptom).
Thrombosis : is the formation, development or presence of a thrombus.
Thrombus : is an abnormal aggregation
of blood factors, primarily platelets and fibrin with entrapment of cellular
elements, frequently causing vascular obstruction at the point of its formation.
Tissue : a group of similar cells united
to perform a specific function.
T-Lymphocytes (or T-Cell) : are a type of white blood cells responsible for cell-mediated immunity. They originate from lymphoid stem cells that migrate from the bone marrow to the thymus, where differentiate under the influence of the thymic hormones.There are three subpopulations of T-lymphocytes :
Transaminases (SGOT or AST, SGPT or ALT) : are enzymes present in liver cells. They are released in bloodstream when a liver damage occurs.
Transmission : the passage or transfer, as of a disease from one individual to another.
Transplant : a surgery to replace
a disease organ with a healthy one from a donor.
Ultrasound Guided Biopsy : is the use of ultrasound imaging to guide a biopsy needle to obtain a sample of tissue for analysis by a pathologist.
Varices : small protruded vessels. Varices in esophagogastric region are one of the major complications of cirrhosis.
Viral Hepatitis : a liver inflammation caused by viruses. There are seven specific hepatitis viruses (HAV, HBV, HCV, HDV, HEV, HGV and TTV). Other viruses, like cytomegalovirus (CMV) and Epstein-Barr virus (EBV), can also cause hepatitis, but their primary target is not the liver.
Viral load : is the number of viral particles in a sample of blood plasma. It is measured by PCR and bDNA tests and is expressed in number of copies or equivalents per millilitre.
Viremia : the presence of virus particles in the blood. It can be detecteted and dosed with a test called PCR.
Virion : a single virus particle, complete with coat.
Wild Type : the naturally-occuring, normal, non-mutated version of a gene or of an organism.
Last update:03/14/2003
Copied with Reprint Permission from "Andrew Rinaldi"
