Use Of Latex Particles Research Articles

The Physiological Changes During Pregnancy

Every adult woman is responsible for their body, and the decisions they make have an impact on their life and their health. However, there are times in life, pregnancy, when a person is deeply responsible for a new life in development. Safe signs of pregnancy are the presence of a fetus seen by ultrasound, listening to heart tones, touching parts of the fetal body and the presence of pregnancy hormones in the urine. After fertilization, measurable concentrations of hCG begin to emerge in the body after 7-10 days, which can be evidenced from the urine or blood of the woman. The immunological tests used today are mostly based on the use of latex particles. The presence of Human chorionic gonadotropin, the polypeptide beta subunit of which is used to prove pregnancy (abbreviated b-hCG) at a concentration of 25 mIU in the urine of a woman, equivalent to a period between the fourth and fifth weeks of pregnancy, can be demonstrated. A planned pregnancy presupposes a series of procedures that will contribute to the proper and complete development of the embryo. Each stage of pregnancy brings certain biological changes in the body of the woman. Pregnancy should last a minimum of 37 weeks, but it can take up to 42 weeks.

Basic and clinical immunology – 3034. Peculiarities of parameters immune system in juvenile rheumatoid arthritis

Juvenile rheumatoid arthritis (JRA) is one of the most common disabling rheumatic diseases in children in the pathogenesis of which play an important role certain subpopulations of lymphocytes. The functions of these immune cells are associated with the molecular receptors on their CD cellular membranes. The aim of the study was to study the state of molecular receptors of peripheral blood lymphocytes in children with JRA. 32 children aged from 5 to 13 years were examined. Diagnosis is based on the criteria of the American Rheumatology Association. In all patients, the diagnosis was confirmed radiographically. 16 healthy children were in control group. Immunological studies were studying the content of CD3 +, CD4 +, CD8 +, CD16 +, CD25 + and CD95 + cells by monoclonal antibodies. Circulating immune complexes were determined using PEG nephelometry. Phagocytic activity was determined with the use of latex particles. Clinical examination showed that the antibody-positive variant of the disease was observed in 80% of patients seronegative - at 20%. I degree of inflammatory activity was found in 31,1%, II degree - at 53,3%, III degree - in 15.6% of patients. Systemic manifestations were observed in 55.5% of children. Analysis of the results of immunological studies have shown that patients with JRA, compared with those of the control group, there was a reduction of CD3 + (P <0,01), CD4 + and CD8 + (P <0,01). The level of CD16 +-cells was reduced 1.7-fold (P <0,01), while the level of proliferating cells and the number of CD95 +-cells was higher (P <0,01). An increase in the CEC and decreased phagocytic activity of neutrophils. Thus, with JRA identified defects in the immune system as a clear expression of reduction of molecular receptors of T lymphocytes and subpopulation composition, suggesting inferiority of T-cell component of the immune system in children suffering from the disease. Rapid chronization of inflammatory process, autoimmune nature of JRA is probably related to functional deficiency of T lymphocytes.

The bidiffractive grating coupler: application to immunosensing

We report on the application of the bidiffractive grating coupler to the sensitive detection of immunoreactions. The thyroid-stimulating hormone (TSH) assay is used as a model system. The capture antibodies are randomly coupled to the functionalized TiO 2 surface using two approaches: direct coupling to the waveguide surface via a self-assembled monolayer of an amino-reactive silane; and coupling via a thin hydrophilic polymer interlayer. All steps of the surface modification are characterized by the bidiffractive grating coupler and the properties of the two surfaces are compared with respect to non-specific binding, amount of antibody immobilization and antigen binding capacity. A direct TSH assay (label free) shows a detection limit of 1×10 −9mol l −1, which corresponds to a surface coverage of 24 pg mm −2. In a sandwich-type assay the sensitivity can be improved by two to three decades by the use of latex particles.

Nasopharyngeal carriage of pneumococci in Gambian children and in their families.

Nasopharyngeal carriage of pneumococci is prevalent among children in developing countries but little is known about the relationship of nasopharyngeal carriage to invasive disease or about the way in which pneumococci spread within households. To determine the prevalence of nasopharyngeal carriage in healthy and sick Gambian children and to investigate transmission within households. Nasopharyngeal swabs were obtained by the per nasal route and cultured for pneumococci on selective media. Pneumococci were serotyped with the use of latex particles coated with type-specific antisera. Pneumococci were isolated from the nasopharynx of 73 (90.1%) of 81 children with invasive pneumococcal disease, 86 (76.1%) of 113 healthy, age-matched control children and 911 (85.1%) of 1071 sick children. Pneumococci belonging to serotypes 1, 14 and 12 were isolated significantly more frequently from cases than from matched controls. In 43 (76.8%) of 56 children with invasive disease, pneumococci isolated from the nasopharynx and from the blood or other sterile site belonged to the same serotype. Pneumococci of the same serotype as the bacterium responsible for invasive disease in a child were obtained from 72 (8.5%) of 843 family members, most frequently from young siblings of the case patients. Nasopharyngeal carriage of pneumococci is more prevalent among young Gambian children than among adults and invasive infections are probably acquired more frequently from siblings than from parents. However, further studies are needed to confirm this hypothesis with more discriminating markers than polysaccharide serotyping.

Use of latex particles to simulate lipemic interferences.

Journal Article Use of latex particles to simulate lipemic interferences. Get access E J Hamilton, E J Hamilton Search for other works by this author on: Oxford Academic Google Scholar J A Caron, J A Caron Search for other works by this author on: Oxford Academic Google Scholar J E Logan J E Logan Search for other works by this author on: Oxford Academic Google Scholar Clinical Chemistry, Volume 27, Issue 8, 1 August 1981, Pages 1475–1476, https://doi.org/10.1093/clinchem/27.8.1475 Published: 01 August 1981

Use of latex particles for analysis of heterokaryon formation and cell fusion

A simple method for the quick and accurate detection of cell fusion utilizing latex particles as cytoplasmic markers was developed and is reported here. The method is particularly useful for demonstrating human skin fibroblast heterokaryons. Ingestion of latex particles did not affect the growth of primary human and established BHK(21)/C(13) hamster fibroblasts. In addition, somatic cell hybridization between hypoxanthine phosphoribosyltransferase-deficient (HPRT-) and thymidine kinase-deficient (TK-) mutants of BHK(21)/C(13) was also unaffected by lates particle ingestion.

The Use of Sensitized Latex in the Identification of Human Bloodstains

The use of latex particles as a means of establishing the origin of unknown bloodstains is described. The particles are sensitized with anti-human serum protein immunoglobulins ; when used as a rapid slide test they agglutinate readily in the presence of normal human serum diluted 1/10,000.

Nitro blue tetrazolium test in children with kwashiorkor with a comment on the use of latex particles in the test.

The nitro blue tetrazolium test was applied on neutrophils from children with kwashiorkor and from control children. The percentage of formazan cells formed in the kwashiorkor patients was significantly less than in the control group in spite of the presence of associated infections in the former. A direct correlation exists between the percentage of formazan cell formation and total serum proteins, albumin, and haemoglobin. These findings may reflect a decreased bactericidal activity of neutrophils in kwashiorkor. The use of latex particles is an unnecessary technical refinement of the test.

An immunologic study of experimental silicosis

Experimental silicosis was produced by injecting guinea pigs intratracheally with silica suspensions. Pathological changes consistent with silicosis were noted at autopsy nine months after injection. Many serological tests such as precipitation, passive hemagglutination, complement fixation, and passive cutaneous anaphylaxis were performed on sera from these animals, but none was successful in demonstrating tissue-reactive autoantibodies. It was found that the use of latex particles sensitized with crude lung extracts could not be used to demonstrate tissue-reactive antibodies. It was shown that such particles actually detect rheumatoid factor like antibodies (antiglobulin antibodies). A modification of the antiglobulin consumption test employing lung connective tissue as antigen was developed and made available to study the tissue antibodies in guinea pigs. This modification was quite sensitive in the detection of lung-reactive antibodies in the experimental animals. The development of this serological technique should permit immunological studies of an experimental model of silicosis to be conducted more easily and under more controlled conditions in the future.

Use of latex particles in serology of tuberculosis.

Use of latex particles in serology of tuberculosis.

Bentonite, Latex, and Cholesterol Flocculation Tests for the Diagnosis of Trichinosis

AT THE Communicable Disease Center of the Public Health Service the bentonite flocculation test (BFT) is used routinely for the diagnosis of trichinosis. This test has been under continual evaluation for sensitivity and specificity since 1952. As part of this evaluation and to keep abreast of new developments, we have attempted, whenever possible, to compare the BFT with new tests and reagents as they have become commercially available. The trichinalatex antigen sold by Hyland Laboratories has been tested intensively. The antigen for the Suessenguth and Kline flocculation test marketed by the LaMotte Company and the reagents for a bentonite flocculation test and a latex test prepared by the Difco Laboratories have received limited evaluations. The accumulated results of our studies may be of help to local laboratories in interpreting their tests. They do not constitute an endorsement or rejection of the proiducts examined. Several particle agglutination tests have been used for the diagnosis of trichinosis. Suessenguth and Kline (1) adapted the Kline test for syphilis to a test for trichinosis and used cholesterol particles Icoated with various trichina antigens. They reported high sensitivity for both human and animal trichinosis (2-4). Campbell (5) and Coudert and Coly (6) used coated collodion particles, and Leikina and Poliakova (7), carmin particles in their tests. Vogel and co-workers (8) employed cholesterollecithin particles. Bozicevich and associates (9) introduced the use of bentonite particles. A series of papers from the CDC. laboratory has reported evaluations of the bentonite test for detection of infection in pigs (10) and in humans (11). The efficacy of Melcher's antigen (13) and of metabolic antigen (12) has been reported as well as that of lyophilized reagents (14). Innella and Redner (15) were the first to describe the use of latex particles coated with trichina antigen. Their test was essentially a modification of the latex test for rheumatoid arthritis developed by Singer and Plotz (16). Muraschi and co-workers have been using the latex test since 1957 and recently published their evaluation of a slide latex-particle agglutination test for trichinosis (17).

The Use of Latex Particles Sensitized With Human Chorionic Gonadotropin in a Serologic Test for Pregnancy

The Use of Latex Particles Sensitized With Human Chorionic Gonadotropin in a Serologic Test for Pregnancy