Hyperhomocysteinemia Epidemiology of hyperhomocysteinemia The prevalence of hyperhomocysteinemia in the general population is not known. Studies looking at the prevalence of http://www-admin.med.uiuc.edu/hematology/PtHomocysteinemia.htm
Extractions: University of Illinois - Urbana/Champaign Carle Cancer Center Hematology Resource Page Patient Resources Hyperhomocysteinemia Home Factor V Leiden Antiphospholipid Syndrome General Clotting Information ... Protein S deficiency Homocystinuria (homocystine excreted in the urine) was first reported in 1962. Homocystinuria is associated with a syndrome of mental retardation, skeletal and visual problems and arterial as well as venous thrombosis. There are two primary enzymes that, when a defect is present, can result in either homocystinuria or hyperhomocysteinemia (hyper=high) as discussed below. Mechanism of Hyperhomocysteinemia: Homocysteine is a naturally occurring molecule in the body and it is required in several reactions that occur within the cells that comprise the human body. The reactions are detailed in the figure above; they result in the formation of cysteine and methionine, which can be further used by the body. If the pathways to either cysteine or methionine are blocked, then homocysteine levels may rise. Three enzymes in the above diagram will be focused on, as they are associated with elevated levels of homocysteine. These enzymes are methylenetetrahydrofolate reductase (MTHFR), cystathionine beta-synthase (CBS) and methionine synthase (MS).
Hyperhomocysteinemia Patient Resources. hyperhomocysteinemia. Home. Factor V Leiden Prothrombin Gene Mutation. hyperhomocysteinemia. Diseases from abnormal http://tmsyn.wc.ask.com/r?t=an&s=hb&uid=24312681243126812&sid=343126
Hyperhomocysteinemia hyperhomocysteinemia. Andrea Cortese Hassett Ph.D., Chief Science Officer Although severe hyperhomocysteinemia is rare, mild hyperhomocysteinemia occurs http://www.itxm.org/tmu2003/issue2003-6.htm
Extractions: Issue # Andrea Cortese Hassett Ph.D., Chief Science Officer, ITxM Diagnostics INTRODUCTION Homocysteine is a naturally occurring, sulfur containing amino acid formed during the metabolism of methionine, an essential amino acid derived from the diet. The interconversion of methionine and homocysteine depends on the availability of the methyl donor 5-methyltetrahydrofolate, cofactors vitamin B and folate, and the enzyme activity of methionine synthase. Elevated intracellular homocysteine concentrations with corresponding increases in blood levels can result from augmented production or reduced metabolism. Although severe hyperhomocysteinemia is rare, mild hyperhomocysteinemia occurs in approximately 5 to 7 percent of the general population. Patients with mild hyperhomocysteinemia are asymptomatic until the third or fourth decade of life when premature coronary artery disease may develop, as well as recurrent arterial and venous thrombosis. MEASUREMENT SPECIMEN REQUIREMENTS Plasma homocysteine is measured on a morning specimen collected in an EDTA (lavender top) tube after an overnight fast. Because homocysteine is continuously released by blood cells, the specimen must be centrifuged and the plasma separated immediately to avoid falsely elevated values. Alternatively, the specimen can be placed on wet ice until it can be centrifuged. Specimens that are not sent to the lab the same day must be spun down and the plasma frozen until testing is performed.
Hyperhomocysteinemia And The Endocrine System Implications For hyperhomocysteinemia and the Endocrine System Implications for Atherosclerosis and Thrombosis Vivian Fonseca , Susan C. Guba and http://tmsyn.wc.ask.com/r?t=an&s=hb&uid=24312681243126812&sid=343126
Hyperhomocysteinemia Extensive donor selection and testing strategies effectively reduce the transmission of viral agents by asymptomatic volunteer blood donors. http://www.itxm.org/tmu2003/issue2003-8.htm
Extractions: Issue # Detection of Bacterial Contamination in Platelet Components Blood Bulletin: Vol. 6, No. 4, DECEMBER 2003 Extensive donor selection and testing strategies effectively reduce the transmission of viral agents by asymptomatic volunteer blood donors. Today, the most frequent transfusion-associated infectious risk in the United States is sepsis associated with bacterial contamination of platelet components. Given the frequency, clinical significance, and potential for fatal complications that the presence of bacteria poses for certain patients, two accrediting agencies (the American Association of Blood Banks and the College of American Pathologists) have issued directives requiring the use of methods to detect and limit bacterial contamination of platelets.
Mice Deficient In Methylenetetrahydrofolate Reductase Exhibit Mice deficient in methylenetetrahydrofolate reductase exhibit hyperhomocysteinemia and decreased methylation capacity, with neuropathology and http://tmsyn.wc.ask.com/r?t=an&s=hb&uid=24312681243126812&sid=343126
TIGC - Hyperhomocysteinemia hyperhomocysteinemia. Background. Elevation of the plasma homocysteine concentration Patients with severe or refractory hyperhomocysteinemia should be http://www.tigc.org/eguidelines/hyperhomocysteinemia02.htm
Extractions: Secondary Developers: D. Lee, M. Mant Hyperhomocysteinemia Background Elevation of the plasma homocysteine concentration (hyperhomocysteinemia) is a common and important risk factor for atherosclerotic arterial disease (Boushey CJ et al., JAMA 274:1049-1057, 1995) and for venous thromboembolism (Ray JG, Arch. Intern. Med. 158:2101-2106, 1998). The risk conferred by homocysteine adds to or even multiplies the risk conferred by factors such as smoking, hypertension, diabetes, and lipid disorders (for arterial disease) and Factor V Leiden (for venous thromboembolism). Even mild elevations of plasma homocysteine confer risk. Homocysteine levels are influenced by diet, as homocysteine is produced from metabolism of methionine, and cleared by metabolic pathways that require folic acid, vitamin B , and vitamin B as cofactors. Low levels of these vitamins are therefore associated with hyperhomocysteinemia. Congenital deficiencies of enzymes in these metabolic pathways, and renal failure, also are important causes of hyperhomocysteinemia. Screening Fasting plasma or serum homocysteine concentrations should be measured as a part of the investigation of selected patients with venous thromboembolism, particularly those with idiopathic thrombosis, recurrent thrombosis, and thrombosis at a young age or at an unusual site (see guideline on Investigation of Suspected Hypercoagulable States). Measurement of a homocysteine level should be considered in patients with arterial disease.
Moderate Hyperhomocysteinemia Decreases Endothelial-Dependent Moderate hyperhomocysteinemia Decreases EndothelialDependent Vasorelaxation in Pregnant But Not Nonpregnant Mice Robert W. Powers http://tmsyn.wc.ask.com/r?t=an&s=hb&uid=24312681243126812&sid=343126
Extractions: Although all information remains accessible via Navigator 4.x and other older browsers, we are considering them obsolete from the standpoint of our interface design. Please visit providers such as Firefox or Microsoft if you wish to upgrade your browser. Thank you! Select a Region Contact Glossary Sitemap ... Abbott Diagnostics Global Your Health Information Homocysteine: The New Risk Factor Cardiovascular Risk Stratification Epidemiology of Hyperhomocysteinemia Homocysteine as a risk factor for coronary heart disease, cerebrovascular disease and stroke ... References and Additional Reading Click on the image to view a larger version. Top of page Dr. Wilson emphasized that there are several measurement considerations to keep in mind when evaluating homocysteine and other emerging CHD risk factors. These include test standardization, assay variability, correlation with currently accepted risk factors, the possibility of nonlinear effects, the potential for improvement in risk prediction, and the cost of the assay. New biological markers for CHD risk should be assayed by standardized techniques, show little interlaboratory variability, and be performed by laboratories that meet the accreditation standards of either the Centers for Disease Control or the College of American Pathologists. In addition, the marker should have little biological variability. For example, while fibrinogen and other acute-phase reactants are useful markers on an individual basis, they have tremendous intersubject variability.
Abbott Diagnostics - Clinical Insights - Trials And Treatment postload hyperhomocysteinemia have normal fasting homocysteine concentrations. Supplemental vitamin B6 will modulate postprandial hyperhomocysteinemia http://www.abbottdiagnostics.com/Your_Health/Heart_Disease/Homocysteine/Clinical
Extractions: Although all information remains accessible via Navigator 4.x and other older browsers, we are considering them obsolete from the standpoint of our interface design. Please visit providers such as Firefox or Microsoft if you wish to upgrade your browser. Thank you! Select a Region Contact Glossary Sitemap ... Abbott Diagnostics Global Your Health Information Homocysteine: The New Risk Factor Cardiovascular Risk Stratification Epidemiology of Hyperhomocysteinemia Homocysteine as a risk factor for coronary heart disease, cerebrovascular disease and stroke ... References and Additional Reading According to Godfried H. Boers, MD, PhD, in 1976 Wilcken et al published one of the first reports of an association of mild hyperhomocysteinemia and premature CHD. The Wilckens' paper described 25 patients under the age of 50 years with angiographically documented coronary artery disease who had elevated levels of cysteine-homocysteine mixed disulfide following methionine loading. These investigators suggested that a reduced ability to metabolize homocysteine may occur when the methionine pathway is stressed in some patients. Subsequent studies by Boers et al and by Clarke and colleagues confirmed the association of hyperhomocysteinemia and premature vascular disease and suggested that the abnormality in these patients represented a heterozygous presentation of cystathionine b-synthase deficiency. Since the standard treatment of homocystinuria at the time was vitamin B
Entrez PubMed The odds ratio for 5year mortality for hyperhomocysteinemia was 1.34 (0.87 to 2.06) in CONCLUSIONS hyperhomocysteinemia is related to 5-year mortality http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=1
Entrez PubMed hyperhomocysteinemia is another risk factor for cardiovascular and The results of the present study indicate that hyperhomocysteinemia is an integral http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=1
HYPERHOMOCYSTEINEMIA Specialty definitions using hyperhomocysteinemia Cystathionine betaSynthase. (references). Top. Frequency of Internet Keywords hyperhomocysteinemia http://www.websters-online-dictionary.org/definition/english/Hy/Hyperhomocystein
Extractions: Philip M. Parker, INSEAD. HYPERHOMOCYSTEINEMIA Specialty Definition: HYPERHOMOCYSTEINEMIA Domain Definition An inborn error of methionone metabolism which produces an excess of homocysteine in the blood. It is often caused by a deficiency of cystathionine beta-synthase and is a risk factor for coronary vascular disease. ( references Source: compiled by the editor from various references ; see credits. Top Specialty definitions using "HYPERHOMOCYSTEINEMIA" Cystathionine beta-Synthase references Top Frequency of Internet Keywords: HYPERHOMOCYSTEINEMIA The following statistics estimate the number of searches per day across the major English-language search engines as identified by various trade publications. Hyperlinks lead to commercial use of the expression at Amazon.com
Hyperhomocysteinemia: A Nutritional Component Of Heart Disease hyperhomocysteinemia. What You Are Not Eating Could Hurt You If you wish to order the brochure on hyperhomocysteinemia with the above information along http://www.pea-lentil.com/homocysteine.html
Extractions: Heart disease is the number one killer in this country, claiming 500,000 lives every year. Factors such as cigarette smoking, high blood pressure and cholesterol, physical inactivity, age, stress, hereditary factors, diabetes, and being a male all contribute to an increased risk of heart disease. However, many heart attacks occur in people without any of these risk factors. Recently studies point to a new risk factor. Homocysteine, an amino acid and a basic unit of protein, appears to be implicated in 10-15 percent of vascular (heart) disease cases. A 1992 study of over 14,000 male physicians found that those with the highest levels of homocysteine had more than three times the risk of heart disease. Foods rich in B vitamins - folate, B12 and B6 - help keep homocysteine at safe levels. In other words, when B-vitamins are provided, the homocysteine levels may decrease. Conversely, low levels of blood folate are consistently related to high levels of homocysteine. Folate (also known as folic acid) seems to have a greater clearing effect on homocysteine levels that B6, B12, or both vitamins combined. Some people may be more prone to homocysteine buildup and may consequently need more B-vitamins.
Effect Of Experimental Hyperhomocysteinemia On Cardiac Structure Effect of Experimental hyperhomocysteinemia on Cardiac Structure and Function in the Rat Ernest Walker1 , Jason Black2 , Cordel Parris3 http://tmsyn.wc.ask.com/r?t=an&s=hb&uid=24312681243126812&sid=343126