Candida Antigen - Disseminated candidiasis associated with the use of broad-spectrum antibiotics, indwelling venous catheters, immunosuppressive therapy, and HIV is a serious clinical problem. The inability of clinicians to detect early dissemination in the face of colonization of multiple body sites often leads to delay in effective treatment, with disastrous results. Although cultures of these sites are frequently positive in these patients, blood cultures are frequently negative, or become positive to late to be of diagnostic use.

Serological techniques for the detection of dissemination or tissue invasion have not proven to be reliable for the clinician. The commensal nature of the Candida species the lag time required for antibody production in the host, and patients with an impaired immune system have all rendered antibody detection tests relatively ineffective.

Candida Antibody - A number of fungal pathogens can be spread systemically from the intestinal lumen to visceral organs. Although many Candida species exist C. albicans and C. tropicalis cause over 80% of the Candida infections in man. Candida probably enters the newborn in the first few days of life and is a normal inhabitant of the gut.

Systemic candidiasis is a fungal infection of the deep organs resulting from the overgrowth and spread of Candida. It is a significant cause of death in the immuino-compromised or those undergoing prolonged antibiotic therapy. Candida may also transmitted by blood transfusions and is also frequently encountered in the elderly.

Elevated Candida IgG and IgM antibodies are characteristic of recent systemic Candida infection.

Elevated Candida IgA antibodies are characteristic of mucosal membrane Candida infection.

Dissacharidases - The enzymes collectively known as the mucosal disaccharidases (lactase, maltase, palatinase and sucrase) are present in normal small intestine and fetal colon. Depending on the disease state, different enzymes are affected. A decrease in the enzyme activity of these disaccharidases has been noted in colonic adenomas, adenocarcinomas and malabsorption. Decreased disaccharidase activity is a good indicator of mucosal injury, with the exception of lactase.

Serum, Plasma and Fecal Porphyrins - The porphyrias are a group of diseases associated with hereditary and acquired deficiencies in the biosynthetic pathway of heme. The laboratory diagnosis of porphyrin disorders rests primarily with the identification of patterns of porphyrin intermediates. Multiple species have been identified for each of the porphyrins based on the order of their substitutions.

Samples from patients suspected of primary or secondary porphyria are diluted in phosphate buffered saline (PBS). Samples are then scanned for emission between the wavelengths of 580 and 650 nm after being excited at 405 nm. The scan is compared to a reference porphyrin curve to determine if the suspected porphyria does exist.

When the levels of total plasma porphyrins are elevated, fractionation is recommended. This method provides quantitative results for all the forms except Protoporphyrin. Reviews of the published literature notes that it is difficult to obtain quantitatively recover Protoporphyrin from biological samples. Therefore it is used as an indication of protoporphyrin and to initiate further testing.

Isohemagglutinin Titer - Individuals produce different titers of isohemagglutinin antibodies based on genetics and state of health. The typical range observed for anti-A isohemagglutinin titer is 32-2048, while that for anti-B is 8-512. Accordingly, there is no normal titer expected from any particular specimen. Under certain conditions or disease states, an autoimmune response is induced and isohemagglutinin titers increase.

Maternal isohemagglutinins are associated with ABO-hemolytic disease of the newborn. Isohemagglutinin titers are performed in cases of suspected parasitic disease. Parasites such as Toxocara, Ascaris, Schistosoma and Plasmodium express A- and B-like antigens on their surfaces, eliciting increases in anti-A and anti-B isohemagglutinin titers.

METHOD:

This is an assay for the qualitative determination of isohemagglutinin titer in serum. In addition to titering anti-A and anti-B antibodies (i.e., isohemagglutinins), the assay includes a determination of red blood cell type to confirm the isohemagglutinin results..

Blood type determination (‘front typing’) and confirmatory testing by isohemagglutinin titer (‘back typing’) are routinely performed using hemagglutination. Hemagglutination is the process by which red blood cells (RBC) agglutinate in the presence of antibodies to yield a solid pellet. Hemagglutination is assessed by visual observation at four levels, categorized as 1-4: one is slight agglutination represented as a grainy appearance of the sample as cells begin to aggregate; four is a solid mass of agglutinated cells; two and three represent intermediate states of increasing agglutination. Blood typing is performed by hemagglutinating a patient RBC sample with commercial antisera; isohemagglutinin titer is determined by observing the highest dilution of patient serum that results in RBC agglutination.

Mycoplasma by PCR - Contamination of cell cultures by Mycoplasma (and other members of the class Mollicutes) is a common occurrence. Several studies support an incidence of over 15% Mycoplasma can be introduced into cell culture from several sources including other cell lines, laboratory personnel, reagents, and more rarely the tissue source used to prepare primary cells. Their small size (~ 0.15 µm) allows them to pass through most 0.22 or 0.45 µm sterilization filters. Also, they are resistant to common antibiotics such as penicillin and streptomycin. Unlike bacteria and fungi, Mycoplasma contamination is difficult to detect and usually does not produce turbidity in the cell culture medium. However, Mycoplasma growth can cause adverse and subtle effects on cells in culture including changes in metabolism; growth; viability; DNA, RNA and protein synthesis; morphology; and virus replication. It can easily lead to unreliable and non-reproducible experiments.

METHOD:

This method uses Real-Time PCR with SYBR® Green I dye for detection. The assay detects a variety of Mycoplasma species including 10 species commonly detected as contaminants of cultured cells: A. laidlawii, M. pirum, M. arginini, M. fermentas, M. hominis, M. hyorhinis, M. salivarium, M. arthritidis , M. pneumoniae and M. orale. This assay detects less common Mycoplasma species. The MycoSensorTM Q-PCR Assay Kit by Stratagene was modified by adding a set of primers specific for the detection of M. pneumoniae. The assay detects as few as 10 copies of genomic DNA. The primers amplify the DNA sequence of a highly conserved region of the 16S ribosomal RNA gene.

Vitamin B1 in serum - Humans obtain thiamin a water-soluble vitamin from their diet. Foods rich in thiamin include yeasts, liver, and cereal grains. Thiamin is absorbed by the intestinal lumen by both passive diffusion and active carrier-mediated transport. Most of the thiamin in serum is bound to proteins, especially albumin. Thiamin is also taken up by red blood cells which may contain up to 85% of the total blood thiamin pool. Thiamin in excess of that which is bound is excreted in the urine.

Thiamin (Vitamin B1) a water-soluble vitamin is found in human blood in the free state, protein bound, and as phospho-esters. This method measures thiamin pyrophosphate. First the peptide and phosphate ester linkages are broken. Then the high molecular weight components are precipitated. Next a fluorescent tag is added to the B1. Finally the B1 is measured by reverse phase HPLC with a flurometric detector.

Home | Company Info | Services | Literature | New Tests | Contact Us
http://www.cambridgebiomedical.com 1-888-497-9952