Archive for the ‘Elisa’ Category

Progesterone ELISA kit blog

Test: Progesterone ELISA kit Cat#: 2077Z

Synonyms: Progesterone EIA kit

Shelf Life: 12-14 months

Total time: ~ 110 minutes

 

Progesterone, a neurosteroid is synthesized from both tissue and circulating cholesterol via pregnenolone through sequential enzymatic actions of desmolase and delta 4-5 isomerase.  Progesterone which regulates a wide range of biological and metabolic functions in the body is the precursor to important steroid hormones such as estrogen, testosterone, and cortisol. It is produced primarily in the corpus luteum of the ovaries in females and testes in males, and in the adrenal glands in both sexes.  Body stores progesterone in adipose tissue.  In blood only 2-10% of the total progesterone circulates as free hormone.   Most of the progesterone in blood is in complex form which is bound to Albumin, Corticosteroid Binding Globulin (CBG), and sex Hormone Binding Globulin (SHBG) [1].

Progesterone’s main function in females is to prepare the endometrium in uterus to accept and sustain the fertilized egg.  It promotes fetal survival and development.  The level of progesterone drops if the egg is not fertilized and menstruation follows. Then progesterone level remains relatively constant throughout the follicular phase of the menstrual cycle. Progesterone concentration increases rapidly following ovulation and remains elevated for 4-6 days and decreases to the initial level 24 hours before the onset of menstruation.  During pregnancy placental progesterone production rises steadily to levels of 10 to 20 times those of the luteal phase peak reaching value as high as 200ng/ml (300-400mg daily) at term [2].

 

 

Progesterone Molecular Structure [3]

 

Progesterone measurements are used to determine ovulation as well as to establish luteal phase defects. Thus progesterone level in blood is useful indicator of ovulation and monitoring luteal function.

At Diagnostic Automation the serum Progesterone ELISA kit offers an accurate prediction of ovulation.

http://www.rapidtest.com/index.php?i=Progesterone-ELISA-kit&id=67&cat=14

Fetal adrenal gland uses large amounts of progesterone supplied by the placenta to make cortisol.  Cortisol is an essential hormone for stress response.  Stress reduces progesterone production as body redirects it into cortisol production to manage and decrease stress level in the body [4& 5].

Recent steroid profiling study offers valuable data for the diagnostics of diseases related to steroidogenesis changes in the fetal and maternal compartments and placenta.  Result showed higher production of active progesterone in fetus with the approaching term [6].

 

Moreover, various studies have demonstrated the supportive role of progesterone on normal development of neurons in the brain.   Following traumatic brain injury progesterone is being utilized as a therapeutic mediator to recover neuron loss and improve cognitive dysfunction.  Multiple mechanisms have been proposed for progesterone role as a neuroprotective agent such as reduction of inflammation following brain trauma, and inhibition of calcium signaling [7&8]. A recent study has proposed progesterone as a candidate to be used as a neuroprotective agent for stroke [9].

 

Progesterone concentration can fluctuate considerably not only from person to person, but also its level varies during day, thus serial measurements are highly recommended.

Measuring progesterone level in blood has been an established method for the detection of ovulation.  Progesterone measurements are used clinically to confirm ovulation and normal function of the corpus luteum in non-pregnant women.

At Diagnostic Automation the serum Progesterone ELISA kit offers an accurate prediction of ovulation.

http://www.rapidtest.com/index.php?i=Progesterone-ELISA-kit&id=67&cat=14

 

 

Indications for progesterone elisa testing:

1. Detecting ovulation

2. Monitoring embryo transfer

3. Monitoring fetal health throughout the high risk pregnancies

4. Identifying high risk patients for abortion early on in pregnancy

5. Checking abnormal bleeding in a non-pregnant woman

6. Diagnosis of ectopic & molar pregnancies

7. Monitoring progesterone replacement therapy

8. Checking normal function of luteum in non-pregnant women

9. Diagnosis of Luteinized unruptured follicle syndrome

10. Detecting ovarian tumors

 

 

Intended use of Progesterone ELISA kit Cat#: 2077Z:

The Diagnostic Automation Progesterone EIA test is for the quantitative determination of Progesterone concentration in human serum valid for detection and monitoring of conditions above.

http://www.rapidtest.com/index.php?i=Progesterone-ELISA-kit&id=67&cat=14

 

 

Materials and Components 

Materials provided with Progesterone ELISA Test Kit:

• Goat Anti-Rabbit IgG-coated Microplate 96 wells

• Progesterone ELISA test Reference Standards: 0, 0.5, 3.0, 10, 25, and 50 ng/ml

Liquids, 0.5 ml each, ready to use

• Rabbit Anti-Progesterone Reagent (pink color), 7 ml

• Progesterone elisa-HRP Conjugate Concentrate (11x), 1.3 ml

• Progesterone elisa-HRP Conjugate Diluent, 13 ml

• Progesterone EIA Control 1, Liquid, 0.5 ml, Ready to use

• Progesterone EIA Control 2, Liquid, 0.5 ml, Ready to use

• TMB Reagent (One-Step), 11 ml

• Stop Solution (1N HCl), 11 ml

 

 

Materials required but not provided:

• Precision pipettes: 5~40μl, and 0.05~0.2ml

• Disposable pipette tips

• Distilled or deionized water

• Vortex mixer or equivalent

• Absorbent paper or paper towel

• Graph paper

• ELISA kit Microplate Washer

• ELISA kit Microplate Reader

 

In addition to progesterone ELISA kit, Diagnostic Automation offers two additional tests for assessment of progesterone level in blood:

17-alpha hydroxy Progesterone ELISA kit (Cat # 1292Z)

Diagnostic Automation 17-Hydroxyprogesterone (17-OH progesterone or 17OHP) elisa kit is expedient for the measurements of levels of 17-OHP which are useful in the evaluation of patients suspected with congenital adrenal hyperplasia.  Since defective enzymes, 21-hydroxylase and 11ß-hydroxilase lead to a buildup of 17OHP level.

http://www.rapidtest.com/index.php?i=17-alpha-hydroxy-Progesterone-ELISA-kit&id=72&cat=14

Progesterone CLIA (Chemiluminescence Immuno Assay) kit (Cat # 9025-16)

Progesterone CLIA detection using Microplate luminometers provides a sensitive, high throughput, and economical alternative to conventional colorimetric methodologies.

http://www.rapidtest.com/index.php?i=Progesterone-CLIA-kit—(Chemiluminescence-Immuno-Assay)&id=535&cat=39

 

 

 

Related kits to progesterone elisa:

 

Beta HCG (Total) ELISA kit (Cat # 4201-16)

Studies have shown that HCG levels can be useful in predicting spontaneous abortions, aiding in the detection of ectopic pregnancy and multiple gestation. Elevated levels of HCG have also been detected in serum from patients with abnormal physiological conditions not related to pregnancy.

http://www.rapidtest.com/index.php?i=Beta-HCG-(Total)-ELISA-kit&id=58&cat=13

 

Luteinizing hormone (LH) ELISA Kit (Cat #4225Z)

This test may be used in conjunction with progesterone elisa kit.  Patients suffering from hypogonadism show increased concentrations of serum LH.  A decrease in steroid hormone production in females is a result of immature ovaries, primary ovarian failure, polycystic ovary disease, or menopause; in these cases, LH secretion is not regulated.

http://www.rapidtest.com/index.php?i=LH-ELISA-kit&id=61&cat=13

 

 

 

 

 

References:

1.Jeremy M Berg, John L Tymoczko, and Lubert Stryer. Biochemistry, 5th edition.2002, New York.  WH. Freeman; ISBN-10: 0-7167-3051-0

2. Hoehn K, Marieb EN. Human Anatomy & Physiology, 2010, San Francisco: Benjamin Cummings; ISBN 0-321-60261-7

3. NCBI

http://pubchem.ncbi.nlm.nih.gov/image/structurefly.cgi?cid=6238

5. Mastorako G, Ilas I. Maternal and fetal hypothalamic-pituitary-adrenal axes during pregnancy and postpartum. Ann N Y Acad Sci. 2003, 997:136-49

6. Hill M, et al. Steroid profiling in pregnancy: A focus on the human fetus, 2013 Apr 10.  J. Steroid Biochem Mol Biol.

7. Pan DS, Liu WG, Yang XF, Cao F (October 2007). Inhibitory effect of progesterone on inflammatory factors after experimental traumatic brain injury. 2007, Biomed. Environ. Sci. 20 (5): 432–8

8. Luoma JI, Stern CM, Mermelstein PG (August 2012). Progesterone inhibition of neuronal calcium signaling underlies aspects of progesterone-mediated neuroprotection. 2012,  J. Steroid Biochem. Mol. Biol. 131 (1-2): 30–6

9. Wong R, Bath PM et al. Progesterone and cerebral ischaemia: the relevance of ageing, 2013 Apr 30. J Neuroendocrinol.

 

 

 

 

Vitamin B12 ELISA kit blog

Vitamin B12 ELISA kit

At Los Angeles-based Diagnostic Automation (focusing on ELISA Kits) we offer two vitamin B12 elisa kits:

1) Food Vitamin B12 ELISA kit to determine vitamin B12 quantitatively in vitaminated food in a significantly faster way (2.5 to 4 hours inclusive sample pretreatment) compared to a conventional microbiological assay (24 to 48 hours)

2) Vitamin B12 ELISA kit to measure the serum concentration of vitamin B12

Vitamin B12, also known as cobalamin, has the largest and the most complicated structure in vitamins.  Cobalamin is an organometallic compound and only known essential molecule with a stable metal-carbon bond.  To discover vitamin B12, elucidate its metabolic roles, discover the signs and symptoms of its deficiency, and to find treatment, took over 100 years [1].  In 1850s Thomas Addison an English physician described a lethal (pernicious) anemia.  In 1930s Castel an American physician discovered the intrinsic factor (IF) essential for B12 absorbance and many years later it was found to be a glycoprotein.  In 1934 Whipple, Minot, and Murphy shared the Nobel Prize for their discovery of treating anemia with liver extract.  In 1950s Dorothy Hodgkin a British chemist described the structure of vitamin B12 and received the Nobel Prize for it in 1964[2].  Different biochemical roles of B12 such as its interaction with folate and their linked role in megaloblastic anemia, was identified subsequently.  B12 continues to be the subject of intense interest in research especially the deficiency in infants secondary to maternal origins and its role in their development [3].

 

 

Molecular structure of Vitamin B12 (Cobalamin)

Cobalamin/vitamin B12 is a water-soluble vitamin with a key role in the normal formation of red blood cells and also normal functioning of the nervous system including brain.  Moreover, it is involved in the DNA regulation; synthesis and fatty acid metabolism, thus effecting energy production in the body.  Every cell of human body needs vitamin B12 for its normal function.  Animal, Plants, and fungi are not capable of producing vitamin B12.  Only archaea and bacteria have the necessary enzymes required for the synthesis of B12 in the form of hydroxocobalamin which is then converted to cobalamin in the human body.  B12 is naturally present in animal foods and can also be received through supplements.  However, proper absorption in the body requires a complex pathway [4].

Vitamin B12 has profound effects on human health and is essential for several crucial functions in the body.  The deficiency manifest when serum levels are below the cutoff point.  In USA the limit is 200 picograms per milliliter (pg/ml) [5].  In Europe and Japan the limit for B12 is 500-550 pg/ml, this level of B12 may explain the lower rate of Alzheimer in these countries compared to USA with lower cut off (200pg/ml) [6].  It is essential to identify the B12 deficiency promptly.

Diagnostic Automation offers a rapid and reliable tool as an ELISA kit for measuring the serum concentration of vitamin B12.  Deficiency of vitamin B12 can manifest with hematological disorder, such as severe anemia requiring blood transfusions, and behavioral changes to serious and permanent nerve damage, neurologic, vascular, and gastrointestinal problems.

Vitamin B12 was discovered through investigation of Pernicious anemia.  Pernicious anemia is a member of the large family of megaloblastic anemias that is characterized by production of large immature and dysfunctional red blood cells in the body.  Pernicious anemia is a form of autoimmune disease that destroys cells in the stomach which are responsible for the production of Cubilin, an intrinsic factor (IF) which is a protein essential for the absorption of B12.  IF is located within the epithelium of intestine and kidney. Mutations in CUBN (Cubilin gene) may play a role in autosomal recessive megaloblastic anemia [7].  Real pernicious anemia constitutes only a small fraction of the cases, however, malabsorption due to diminished secretion of gastric acid and enzymes necessary for the cleavage of protein- B12 bond from food is the main concern.  It is very important to note that maintaining an optimal status of vitamin B12 is not only dependent on adequate dietary intake but more critically on its effective absorption which declines with age.

Vitamin B12 is absorbed through saliva at the ingestion stage, and then during digestion.  The vitamin B12 from food proteins is released with the help of acids in the stomach.  Absorption of B12 depends on intrinsic factor (IF) which is present in the gastric juice.  IF combines with vitamin B12 and facilitates its absorption in the lower part of the small intestine. Vitamin B12 and Folate deficiencies have similar symptoms, so it is important to have accurate tests that can detect the differences.  Fortunately, Vitamin B12 deficiency can easily be treated and prevented [8].  It is very important to be aware of it since there is a high prevalence of mild, subclinical B12 deficiency in asymptomatic individuals, especially with individuals at high risk such as vegan/vegetarian [9].

Delay in the diagnosis and treatment of vitamin B12 deficiencies can lead to development of severe and irreversible neurologic damage.  Although vitamin B12 deficiencies was estimated to occur at a frequency of 1 in every 31 adults 51 years of age or older in USA population, but the incidence of vitamin B12 deficiency is far more common than previously assessed [10; 11].  The rise in gastric bypass surgeries in obese women and growing incidence of gastrointestinal issues such as coeliac disease, Crohn’s, and ulcerative colitis, plus the increasing number of vegan/vegetarian mother are the growing concern [12].  These conditions substantially decrease the absorption of vitamin B12 which adversely affects the development of children born of these women. The association between vitamin B12 and cognitive development in children has been observed in infant born to vegan and vegetarian mothers.

A recent study in infants with B12 deficiency has reported diverse clinical abnormities including hypotonic muscle, apathy, cerebral atrophy, and nerve cell demyelination.  Some of these symptoms were reversible since, a rapid improvement in neurological symptoms was reported after vitamin B12 therapy.  However, in long term follow up many of these infants showed serious delay in cognitive and language development.  Babies born to vegetarian mothers may show deficiency of vitamin B12.  Delayed detection and treatment in infants with vitamin B12 deficiencies, can lead to severe and permanent damage to their nervous system.

At Diagnostic Automation (focusing on “ELISA Kits”) we offer vitamin B12 elisa kit which informs mothers before their pregnancy and upon the detection of low level of B12 using vitamin B12 elisa kit, supplement intake can prevent the complications due to deficiency if that is the primary cause of the deficiency.  Although our vitamin B12 serum elis kit is very fast and accurate, Homcysteine and methylmalonic acid can also be used to confirm a vitamin B12 deficiency for cases with ambiguous initial results because metabolic changes often precede low cobalamin levels [13].

Homocysteine levels in blood are influenced by blood levels of B-complex vitamins: cyanocobalamin (B12), folic acid (B9) and pyridoxine (B6).  Studies have shown that high plasma total homocysteine levels are associated with an increased risk of atherosclerotic diseases. Elevated level of homocysteine which is an amino acid with biological functions in methionine metabolism is a risk factor for cardiovascular events.  Cardiovascular disease, including coronary artery disease, stroke and congestive heart failure, is the number one cause of death worldwide.  Thus, it has been suggested that B vitamin supplementation might reduce the risk of myocardial infarction and stroke.

Preventive strategies might include healthy people with low or high risk for developing cardiovascular disease and people with an established cardiovascular disease to take these supplements.  A study including 12 randomized clinical trials involving 47,429 participants show no evidence that homocysteine lowering interventions such as supplementations of vitamins B12, B9 or B6, prevent myocardial infarction and stroke.  However, multiple studies have shown a significant improvement.

Heart Outcomes Prevention Evaluation 2 (HOPE 2) trial reanalysis, showed a reduced incidence of nonfatal stroke with long term (over 3 years) treatment with B vitamins [14-16].  Patients with homocystinuria are prone to thromboembolic events even with minor surgeries.  Levels of homocysteine should be reduced to a near normal level before any surgery.   Increased levels of methylmalonyl CoA and homocysteine in sever form can affect the vascular system and increase the diseases such as Parkinson, atherosclerosis, heart diseases, and stroke. It is postulated that the effect might be through increased level of stress at the cellular level, eventually leading to apoptosis (programed cell death).

Vitamin B12 has high level of importance in public health, not only because of its deficiency leading to megaloblastic anemia and irreversible nerve damage, but also because there are emerging evidence that links vitamin B12 deficiencies to an increased risk of a number of age related diseases, such as cardiovascular disease, cognitive dysfunction, and dementia.  Moreover, there are concerns relating the imbalance of B12 and folate, especially the potential adverse effects for older adults with low vitamin B12 status and over exposure to folate especially in countries with mandatory fortification of food with folate. Thus, inter relationship between vitamin B12 and folate is an important emerging issue in aging population.

Vitamin B12 deficiency can easily be treated and prevented.  There are inexpensive treatment options available as B12 supplement to treat a vitamin B12 deficiency. The treatment is safe, effective, with no known toxicity. To prevent B12 deficiency, all patients 51 years of age and older should be recommended to take B12 supplement daily however, the dosage recommendation may vary.  Recent studies show that in people with malabsorption problems of B12, high dose of oral or nasal intake may be as effective as injection.  However, in severe cases of deficiency such as pernicious anemia and neurological symptoms injection is still the preferred method of administrating vitamin B12.  In USA cyanocobalamin is the most frequent form of B12 supplementation, however recent research prefers hydroxycobalamins which is more common in Europe and it has shown to be superior to cyanocobalamin.

Finally, to identify B12 deficiency the first step is to take an accurate test to determine the level of B12 in the serum.  At CORTEZ DIAGNOSTICS we offer a rapid and reliable vitamin B12 deficiency elisa test kit proved to be both accurate and fast in determining B12 concentration in blood.  The next step is identifying the mechanism and problem leading to B12 deficiency.  This is a challenging step and requires professional help, after that the suitable form of B12 in a form of injection, oral, nasal, and sublingual and the dose and length of treatment will be determined easily.  All patients with unexplained hematologic or neurologic signs and symptoms should be evaluated for B12 deficiency since it is easy to miss the B12 deficiency.

 

Indications for B12 testing:

Megaloblastic or Pernicious anemia: a condition in which there is a lack of an intrinsic factor (IF)

Hyperhomocysteinaemia: an inherited disorder of the metabolism the amino acid methionine and Homocystinuria: also known as cystathionine beta synthase deficiency, both are associated with atherosclerosis, venous and arterial thrombosis.  Acquired forms can be treated with vitamins B12 and B6 and folate

Peripheral neuropathy: damage to the nerve of the peripheral nervous system, may be caused by diseases or trauma to the nerve or as a side effect of a systemic illness

Patients with GI problems: patients with gastritis (long term use of acid-reducing drugs), gastric surgery (e.g., gastric bypass, gastrectomy), gluten intolerance or intestinal resorption disorders, atrophic gastritis (a thinning of the stomach lining that affects up to 30% of people aged 50 and older)

Conditions affecting the small intestine: such as Crohn’s disease, Celiac diseases, parasite (B12 utilizing fish tapeworm such as the Diphyllobothrium latum) or bacterial overgrowth in the small intestine and viral infection (e.g. HIV)

Alcoholism: decrease vitamin B12 absorption

Autoimmune disorders: such as Grave’s disease or systemic lupus erythematous

Pancreatic insufficiency

Patients with thrombosis

Chronic liver and kidney disease

Vitamin B12 deficiency from diet: vegan and vegetarians; pregnancy and lactation

 

 

References:

1. Scott J.M. Molloy A.M. The Discovery of Vitamin B12. Ann Nutr Metab 2012;61:239–245

2. Dorothy Crowfoot, et al. Structure of Vitamin B12: The Crystal Structure of the Hexacarboxylic Acid derived from B12 and the Molecular Structure of the Vitamin. Nature 176, 325 – 328 (20 August 1955)

3. Pepper MR, Black MM . B12 in fetal development. Semin Cell Dev Biol. 2011, 22(6):619-23

4. Jeremy M Berg, John L Tymoczko, and Lubert Stryer.  Biochemistry, 5th edition W H Freeman; 2002. ISBN-10: 0-7167-3051-0

5. Goodman M, Chen XH, Darwish D. Are US lower normal B 12 limits too low? 1996. J Am Geriatr Soc 44 (10): 1274–5

6. Mitsuyama Y, Kogoh H. Serum and cerebrospinal fluid vitamin B12 levels in demented patients with CH3-B12 treatment–preliminary study. 1988. Jpn. J. Psychiatry Neurol.42 (1): 65–71

7. Stabler SP, Allen RH. Megoblastic anemias. In: Goldman L, Ausiello D, editors. Cecil Textbook of Medicine. 22nd ed. Philadelphia: W. B. Saunders Company; 2004. p. 1050-7

8. Medline plus, B12 deficiency: https://www.nlm.nih.gov/medlineplus/ency/article/000574.htm

9. de Benoist B.  Conclusions of a WHO Technical Consultation on folate and vitamin B12 deficiencies. Food Nutr Bull. 2008; 29(2 Suppl):S238-44

10. den Elzen WP, Gussekloo J. Anaemia in older persons. Front Hum Neurosci. 2013; 7: 97

11. Hughes CF, Ward M, Hoey L, McNulty H. Vitamin B12 and ageing: current issues and interaction with folate.  2013 April 16; Ann Clin Biochem.

12. Dror DK, Allen LH. Effect of vitamin B12 deficiency on neurodevelopment in infants: current knowledge and possible mechanisms. Nutr Rev. 2008; 66(5):250-5.

13. Sally P. Stabler. Vitamin B12 Deficiency. N Engl J Med. 2013; 368:149-160

14. Toole JF. et al. Lowering homocysteine in patients with ischemic stroke to prevent recurrent stroke, myocardial infarction, and death: the Vitamin Intervention for Stroke Prevention (VISP) randomized controlled trial. JAMA. 2004;291(5):565-75

15. Spence JD. Homocysteine-lowering therapy: a role in stroke prevention? Lancet Neurol. 2007;6(9):830-8

16. Saposnik G. et al. Homocysteine-lowering therapy and stroke risk, severity, and disability: additional findings from the HOPE 2 trial. Stroke. Apr 2009;40(4):1365-72

 

 

C-reactive protein (CRP) ELISA kit | Lipoprotein(a) [Lp(a)] ELISA kit | Digoxin ELISA Kit

Cardiac Makers Elisa Kits

At DIAGNOSTIC AUTOMATION Inc.   (focusing on ELISA Kits) we take advantage of an influx of new technologies and information incorporating them into novel tests which enables us to offer innovative diagnostic tests every day.  In addition to our 3 in 1 CARDIAC MARKERS TEST (cardiac elisa kits: Troponin I elisa kit, CK-MB elisa kit, myoglobin elisa kit)

http://rapidtest.com/blog/3-in-1-cardiac-markers-rapid-test-troponin-ckmb-myoglobin

Los Angeles-based Diagnostic Automation Inc. is pleased to offer three additional tests in forms of cardiac elisa kits (Cardiac Markers Rapid Tests) to customers around the world available in cassette format. These elisa kit tests are immunochromatography assays for the determination of three biochemical markers: C-reactive protein (CRP) ELISA kit, Lp(a) elisa kit,  and Digoxin ELISA Kit,  simultaneously in human serum or whole blood.

 

1. C-reactive protein (CRP) ELISA kit 

C-reactive protein (CRP): CPR is composed of five protein subunits, produced by the liver and found in blood that plays a key role in the innate immune response.  The gene for this protein is on chromosome 1q21-q23[1].  CRP is a marker for inflammation within the body and has been promoted as a screening test for coronary artery disease [2].  Studies show that elevated levels of CRP are associated with a greater risk of psychological stress and clinical depression.  Elevated levels of CRP may be indicative of elevated levels of certain cytokines, which can increase feelings of stress or depression. On the other hand, it is possible that depression or stress is a cause of elevated level of CRP.  Irrespective of other factors, the study found that healthy people with CRP level above 3mg/liter had two to three fold increased risk of developing depression [3].

Model of C-reactive protein molecular structure [1]

Diagnostic applications: Role in cardiovascular disease

Strong evidence indicates that patients with elevated basal levels of CRP are at an increased risk of hypertension, heart diseases, and diabetes.  C-reactive protein (CRP) is proposed as a screening test for predicting risk and guiding preventive approaches in cardiac diseases [4].  Normal concentration in healthy human serum is usually lower than 10 mg/L, slightly increasing with aging.  Higher levels are found in late pregnant women, mild inflammation and viral infections (10–40 mg/L), active inflammation, bacterial infection (40–200 mg/L), severe bacterial infections and burns (>200 mg/L).  The half-life of CRP is constant, thus, CRP level is mainly determined by the rate of its production.  A level above 2.4 mg/L has been associated with a doubled risk of a coronary event compared to levels below 1 mg/L.  Inflammation can play an important role in atherosclerosis, the process in which fatty deposits build up in coronary arteries. Interest in CRP originated when studies found that patients with unstable angina or chest pain had high levels of this marker.  Researchers found that CRP could be used to predict who would go on to have a heart attack.  Moreover, in a meta-analysis of 20 studies involving 1,466 patients with coronary artery disease, CRP levels were found to be reduced after exercise interventions.  Among those studies, higher CRP concentrations or poorer lipid profiles before beginning exercise were associated with greater reductions in CRP [5].  Other studies have shown that CRP isn’t a predictor of heart attack risk in people without symptoms of heart disease.

(CRP) ELISA kit: At Diagnostic Automation using elisa kit,  CRP level can be measured with a simple blood test .   There are scientific evidences that by treating people with high CRP levels, their likelihood of developing a heart attack or stroke will decrease.

How can CRP values predict potential heart disease?

According to the American Heart Association (AHA) and the Center for Disease Control (CDC), the following guidelines are recommended for the assessment of cardiovascular risk in regards to CRP levels:

CRP is 1 milligram (mg) per liter or less , Low risk for cardiovascular disease

CRP is between 1 and 3 mg per liter, Moderate risk for cardiovascular disease

CRP greater than 3 mg per liter, High risk for cardiovascular disease

CRP level of greater than 10 mg per liter may be seen in an acute plaque rupture such as, a heart attack or stroke, provided there is no other explanation for the elevated level such as other inflammatory or infectious diseases

The CRP level can provide additional information about an individual’s cardiovascular risk in conjunction with other known cardiac risk factors, such as, diabetes mellitus, high blood pressure, high cholesterol, obesity, age, and smoking.  Some experts recommend checking the serum CRP level routinely along with the cholesterol level.  Ideally, for cardiac risk testing, it is advisable to use the average between 2 separate CRP levels drawn 2 weeks part.  According to the American Heart Association checking the CRP level for the entire adult population is not recommended.

 

2. Lipoprotein(a) [Lp(a)] ELISA kit

Lp(a): Lipoprotein (a), also called Lp(a) is a subclass of Lipoprotein consists of an LDL-like particle and the specific apolipoprotein(a) [apo(a)].  Lp(a) plasma concentrations are highly heritable and mainly controlled by the apolipoprotein(a) gene (LPA) positioned on human chromosome 6q26-27.  The protein encoded by this gene is a serine proteinase that inhibits the activity of tissue-type plasminogen activator.  Proteolytically cleaved portion of this protein results in fragments that attach to atherosclerotic lesions and promote thrombogenesis.  Elevated plasma levels of this protein are linked to atherosclerosis [6].

Diagnostic applications:

A strong correlation between elevated level of Lp(a) and heart disease was confirmed by many studies which led to the consensus that Lp(a) is an important independent predictor of heart disease [7].  Evidence from several studies suggest that elevated plasma Lp(a) increases the cardiac diseases risk associated with more traditional risk factors. The clinical use of Lp(a) measurement is to assess the risk of cardiovascular disease.  We use a an elisa kit to measure this specific type of lipoprotein called lipoprotein-a, or Lp(a) in blood.  Normal values are below 30 mg/dL (milligrams per deciliter).  Normal value ranges may vary slightly among different laboratories.  Higher than normal values of Lp(a) are associated with a high risk for atherosclerosis, stroke, and heart attack.  Substantial increases are secondarily observed in nephrotic syndrome and end-stage renal disease, however environmental factors such as diet, and exercise do not have a major impact on the level of Lp(a).  Although Lp(a) is considered a risk factor for heart disease, but the plasma Lp(a) determinations should be limited to either patients at high risk for the development of cardiac diseases or patients at borderline risk for the development of cardiac diseases in whom uncertainty may exist about how aggressively to treat modifiable risk factors such as elevated LDL and cholesterol [8].  Multiple studies have shown that Aspirin and Niacin (Vitamin B3) in high doses, available by prescription known to significantly reduce the level of Lp(a) in some individual with high Lp(a) level

At Diagnostic Automation Lp(a) level can be measured with a simple blood test using Lp(a) ELISA kit with fast and accurate results in 120 minutes.

Model of Lipoprotein, Lp(a) molecular structure [1]

3. Digoxin elisa Kit

Digoxin: Digoxin is a cardiac glycoside which has different products with significant bioavailability and it is used to treat congestive heart failure, atrial fibrillation and paroxysmal atrial tachycardia [9].  Many drugs interact with digoxin, often requiring an adjustment of the digoxin dose [10].  Digoxin is cleared by the kidney and its clearance is low in premature neonates, increases in full term neonates, reaches a maximum in infants and decreases slowly during childhood and adulthood, with an apparent increase in susceptibility to toxicity with age [11, 12]. The circulating half-life is 1 to 1.6 days in patients with normal renal function.  The myocardial concentrations of digoxin to serum levels remain relatively constant during normal renal function.

This distribution ratio of digoxin is approximately 29 to 1 between the heart and serum. Thus, monitoring digoxin therapy by measurement of serum levels is feasible from the pharmacological standpoint, since serum levels are related to tissue levels following post-absorption equilibration.

Recent study has shown that Digoxin has at least 2-compartment behavior. Its pharmacologic and clinical effects correlate not with serum digoxin concentrations but with those in the peripheral non-serum compartment.  Digoxin improves the strength of myocardial contraction and results in the beneficial effects of increased cardiac output, decreased heart size, decreased venous pressure, and decreased blood volume.

Digoxin therapy also results in stabilized and slowed ventricular pulse rate. These therapeutic effects are produced through a network of direct and indirect interactions upon the myocardium, blood vessels, and the autonomic nervous system.  Moreover, recent study show that Digoxin induces calcium uptake into cells by forming transmembrane calcium channels [13].

Digoxin is well absorbed after oral administration and is widely distributed to tissues, especially the heart, kidney, and liver. A number of factors can alter normal absorption, distribution, and bioavailability of the drug, including naturally occurring enteric bacteria in the bowel, presence of food in the gut, strenuous physical activity, ingestion of quinine or quinidine, and concomitant use of a wide range of drugs. Children generally require higher concentrations of digoxin.

After oral administration, there is an early rise in serum concentration. Equilibration of serum and tissue levels reaches at approximately 6 to 8 hours. For this reason, blood specimens for digoxin analysis should be drawn at least 6 to 8 hours after drug administration.  Digoxin is excreted primarily in the urine. The average elimination half-life is 36 to 40 hours, but may be considerably prolonged in those with renal disease, causing digoxin accumulation and toxicity.

Symptoms of digoxin toxicity often mimic the cardiac arrhythmia’s for which the drug was originally prescribed for example, heart block and heart failure.  Other typical symptoms of toxicity include gastrointestinal effects, including anorexia, nausea, vomiting, abdominal pain and diarrhea, and neuropsychologic symptoms, such as fatigue, malaise, dizziness, clouded or blurred vision, visual and auditory hallucination, paranoid ideation, and depression.

 

 

Model of Digoxin molecular structure [1]

 

Diagnostic applications:

A practical and sensitive method of digoxin quantitation in serum is by Digoxin ELISA kit which we offer at Diagnostic Automation.  When digoxin is first prescribed, it takes about 1 or 2 weeks to stabilize in the blood and in the target organ which is heart.  Digoxin first test should be done at around that time, in order to give an accurate reflection of the blood level and correct dosage of digoxin.  Test performed before this period, may not show the correct levels in the blood.

The age or gender of the person being tested, health history, the method used for the test, and many other factors may affect when and how often a lab test is required. The therapeutic range is 0.8 to 2.0ng/mL for those being treated for heart failure and levels >4.0 ng/mL may be potentially life-threatening.  This range for digoxin has been established over time.  Once the dosage level is determined, digoxin levels are monitored routinely, at a frequency determined by the doctor, to verify correct dosage and if any changes occur in drug source, dosage, or other medications taken at the same time.  Recent studies may help to improve patient selection for digoxin therapy, since Digoxin therapy may improve the prognosis of advanced heart failure patients with atrial fibrillation.  However, no benefit of digoxin was demonstrated for patients in with sinus rhythm [15]

Routine measurement of serum digoxin concentration is probably not necessary in stable patients [16].  Laboratory tests may be done for many reasons. Tests are performed for routine health screenings or if a disease or toxicity is suspected.  Lab tests may be used to determine if a medical condition is improving or worsening.  Lab tests may also be used to measure the success or failure of a medication or treatment plan.  Moreover, Digoxin measurement is necessary in the following situations:

To check if  a patient has reached steady state with a new digoxin dose

Following significant change in renal function

Following addition or discontinuation of a potentially interacting drug

Follow up on signs or symptoms consistent with digoxin toxicity

After introduction of any medication which may affect the levels of digoxin in the blood

After  intestinal or stomach illness which also affect the absorption of digoxin

In patients with any kidney problems, which affect the secretion of digoxin

Patients with cancer or thyroid disease who have altered  levels of digoxin in the blood

In patients undergoing therapy with high biotin doses (>5 mg/day), specimens should be drawn at least 8 hours after the last biotin administration. “Digoxin-like” immunoreactive factors may cause falsely-elevated values in some neonates and patients with advanced liver or renal disease.

 

 

 

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16. Jorge E et al. Digoxin in advanced heart failure patients: A question of rhythm . Rev Port Cardiol. 2013;32(4):303-10