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The use of dry blood spots (DBS) on filter paper has become of increasing interest in the field of immunoassay over the last years due to the advantages this mode of presentation brings, enabling its use in countries where resources are scarce or limited to accomplish epidemiological studies. In this work, the optimal conditions for the elution of dry blood spots (3 mm disks) collected on filter paper were determined. Serum samples and the elution conditions establish for 5 mm disks were taken as reference in the detection of specific antibodies to Trypanosoma cruzi by using the indirect UMELISA® CHAGAS (International Tecnosuma S.A.) immunoassay based on Ultra Micro Analytic System (SUMA®). Twelve sero-positive serum samples for Chagas disease from Colombia were confirmed by indirect immunofluorescence (IFI) and ELISA -- Chagatek®, and 75 DBS on filter paper from Bolivia reactive by UMELISA® CHAGAS were evaluated. Additionally, serum samples and DBS negative to Chagas disease from healthy donors from Havana Province Blood Bank were tested. The sensitivity and specificity study results for 3 mm and 5 mm disks were similar. Reduction of the disk diameter allows increasing the number of diagnostic tests, from a very same spot, for the detection of other disease such as the acquired immunodeficiency syndrome, hepatitis B and C, among others. [ABSTRACT FROM AUTHOR]

Objectives. To estimate the prevalence of antibodies against measles, rubella and hepatitis B in children aged between 1 and 4 years in Peru. Materials and methods. A national survey was conducted based on a questionnaire and capillary blood sample taken on filter paper in order to study antibodies against measles, rubella and hepatitis B in children from 1 to 4 years of age. A stratified, multistage, probability sampling design was used to be representative at the national level and at level of seven ambits, including the Metropolitan Lima Area, the rest of the urban coast, the rural coast, the urban highlands, the rural highlands, the urban jungle and the rural jungle. The capillary blood samples were processed according to the standardized protocols for detection of antibodies using the ELISA technique and commercial reagents. Results. The survey showed a national prevalence of antibodies against measles, rubella and hepatitis B of 91.6% (CI 95%: 90.6%; 92.7%), 91.3% (CI 95%: 90.3%; 92.4%) and 95.9% (CI 95%: 95.0%; 96.8%) respectively. There was no evidence of significant differences in the prevalence among the ambits of study or among the socioeconomic strata of the conglomerates for any of the three types of antibodies. Conclusions. In children from 1 to 4 years of age, the national prevalence of antibodies against measles and Rubella was between 90-93%, while the prevalence of antibodies against Hepatitis B (anti-HBsAg) was between 95-97%. [ABSTRACT FROM AUTHOR]

The Center of Immunoassay (CIE) is a research-production complex aiming at the development and production of reagents and instrumentation for medical diagnosis based on immunoenzymatic techniques using the great specificity of the antigen-antibody interactions and the advantages of the reactions catalyzed by enzymes. Its main line is the Ultra Micro Analytical System (SUMA), consists of a technology of equipments and reagents to perform immunoenzymatic analyses at a low cost, which makes it particularly adequate for prevention health programs that require the processing of a big number of samples. In order to achieve a desirable quality warrant, different software systems have been developed for more than a decade, that have been used in the quality assessment process in the laboratories. Under the name of SAC 2.0, the CIE has developed a version of a system for quality control that is able to perform the assessment process totally automated. This paper describes the elements considered in its conception as well as the advantages obtained from automation, which show how important the developed tools are for the proper functioning of the SUMA laboratories allocated not only in Cuba but in other countries as well. [ABSTRACT FROM AUTHOR]

The antiphospolipid syndrome (APS) is an autoimmune disease characterized by recurrent fetal loss, thrombotic events (arterial or venous) and hemocytopenic disorders associated to high titers of circulating aPL Two variants of the APS have been described. Primary APS is a clinical entity without evidence of any other autoimmune disease and secondary APS is a clinical disorder mainly associated with Systemic Lupus Erithematosus (SLE). aPL are a widely group of immunoglobulins directed against different components or proteins factors. In 1990 three groups of researchers identified that β2GP-I is the mainly antigenic target of aPL in APS patients. There are evidences that show that more than one pathogenic mechanism is involved in the development of the APS. The best documented clinical manifestations associated with the APS are recurrent fetal loss and thrombotic disorders. The latter is based on observations in vivo in animal models and in vitro on the effects caused by β2GP-I antibodies from patients with APS or from animals which cause experimental APS. The objective of the present paper is to show the pathogenic mechanisms that participate in the development of the APS. We also presented evidence that shows that β2GP-I induces pro-inflammatory, pro-adhesive and pro-coagulant disorder. [ABSTRACT FROM AUTHOR]

White blood cells also known as leukocytes play a significant role in the diagnosis of different diseases. Digital image processing techniques have successfully contributed to analyze the cells, leading to more accurate and reliable systems for disease diagnosis. However, a high variability on cell shape, size, edge and localization complicates the data extraction process. Moreover, the contrast between cell boundaries and the image's background varies according to lighting conditions during the capturing process. On the other hand, Artificial Immune Systems (AIS) have been successfully applied to tackle numerous challenging optimization problems with remarkable performance in comparison to classical techniques. One of the most widely employed AIS approaches is the Clonal selection algorithm (CSA) which allows to proliferate candidate solutions (antibody) that better resolve a de- terminate objective function (antigen). This paper is thus focused on the segmentation, localization and measurement of leukocytes from other different components in blood smear images. The algorithm uses two different CSA systems, one for the segmentation phase and other for the leukocyte detection task. In the approach, the detection problem is considered to be similar to an optimization problem between the leukocyte and its best matched circle shape. On the other hand, Clonal selection algorithm (CSA) is one of the most widely employed AIS approaches. The algorithm uses the encoding of three points as candidate leukocytes over the edge image. An objective function evaluates if such candidate leukocytes are actually present in the edge image following the guidance of the objective function's values. A set of encoded candidate leukocytes are evolved using the CSA so that they can fit into the actual leucocytes shown by the edge map of the image. The obtained results in comparison with the state-of-the-art algorithms validate the efficiency of the proposed technique with regard to accuracy, speed, and robustness. [ABSTRACT FROM AUTHOR]

During the past few years technological advance have been allowed the developing of techniques that help to the diagnosis of multiple diseases. In the case of the autoimmune diseases, immunological techniques are helpful since they allow the detection of multiple autoantibodies at the same time with small volumes of sample. Together with the development of the new techniques, sensitivity and specificity in the detection of the antibodies specificities' also have been increased, in such a way that the clinicians can count with tests that allow them to make early diagnoses with greater certainty and also to follow the course of the disease based on the variation of the antibodies presents in the patient's samples. It is important to emphasize that the new techniques of laboratory that are used for the support of the diagnosis of autoimmune diseases, no longer are exclusive for research laboratories but by their facility of standardization, quality control and reproducibility they can be used in clinical laboratory of medium and small sizes. In the present paper we describe those techniques with greater application in the clinical laboratory of autoimmune diseases. [ABSTRACT FROM AUTHOR]

Immunity to hepatitis A virus (HAV) is in first instance due to neutralizing antibodies. Neutralization assays are essential to evaluate new candidate vaccines against this pathogen. In this paper, an in vitro neutralization assay to evaluate HAV vaccine candidates using phage-display technology is described. 10³ and 10² DICT50 of HAV were incubated with different antibodies preparations and were inoculated onto plates with FRhK4 cells. After seven days of incubation, the neutralizing titer was determined as reciprocal of the serum dilution reducing HAV growth (inhibition of CPE) by 50%. 10³ and 10² DICT50 were neutralized by 7E7 anti-HAV monoclonal antibody and anti-VHA positive human sera (A12 and A31). Negative controls of the assay did not neutralize viral infectivity. Sera from mice immunized with phages displaying VHA mimotopes had neutralizing titers from 4 - 16. Neither negative control nor pre-immune and sera from mice immunized with M13 wild type phage neutralized HAV. A simple and faster in vitro neutralization assay was developed to evaluate new HAV vaccine candidates. [ABSTRACT FROM AUTHOR]

Introduction: rhesus alloimmunisation remains a common disease in Colombia in spite of universal immunisation having been implemented with immunoglobulin anti-D (Rho) for all susceptible pregnancies. Rh alloimmunisation is a condition requiring risk factors to be identified, all pregnancies to be suitably screened and timely referral to a maternal foetal medicine unit ensured to minimise foetal complications and provide foetal intervention as necessary. Objective: this review was aimed at summarising the available data to provide the reader with tools helping to improve medical care by reviewing the exactitude of screening methods and early diagnosis and the effectiveness of non-invasive and invasive methods of treatment. Methodology: the literature in PubMed, EBSCO, Ovid and ProQuest databases was reviewed. Original papers, reviews, guidelines and bulletins published between 2000 and 2008 were included. Results: antibody titres and middle cerebral artery Doppler were seen to be the screening tools usually used for identifying haemolytic anaemia in the foetus and neonates in Rh alloimmunisation. Rh alloimmunization treatment included close follow-up, intrauterine transfusion and timely delivery and prevention of Rh alloimmunisation by immunoglobulin anti- D (Rho). Conclusion: knowledge of the disease will lead to early recognition of the risk factors and early diagnosis for identifying foetuses at risk which are susceptible to intrauterine therapy. [ABSTRACT FROM AUTHOR]

Diffuse alveolar hemorrhage, a serious and frequent life-threatening process, can occur in a wide variety of disorders, systemic autoimmune diseases, conditions associated with anti-neutrophil cytoplasmic antibodies, anti-glomerular basement membrane antibody, including mitral stenosis inhaled toxins or infection, and drug allergies. These causes have no common denominator, but the end result, of capillary inflammation and hemorrhage, is the same. The capillaritis seen in diffuse alveolar hemorrhage is present exclusively in the lung and is not part of a more generalized systemic vasculitis. A recent article highlighted the central role of the neutrophils in this process, and suggested that in diffuse alveolar hemorrhage the neutrophils present in the lung may change the associated immune complexes and transfer them out of the vascular system into the alveoli. This paper reviews the inflammation seen during the acute lung bleeding and during remission period. We describe the curse of three patients admitted to UCI with diffuse alveolar hemorrhage. Because diffuse alveolar hemorrhage is a common finding in a variety of pathological conditions, we then explore the possible evolutionary mechanisms behind diffuse alveolar hemorrhage. [ABSTRACT FROM AUTHOR]

Production of specific antibodies against compounds of low molecular weight (antibodies antihaptens) require the design of an immunization scheme employing as immunogen.a convenient synthetized hapten-carrier protein conjugate. A large number of organic compounds has been used as haptens, for example carboxylic acids as vanilmandelic acid (VMA), homovanillinic acid (HVA), palmitic acid, stearic acid and oleic acid, amines as norepinephrine, epinephrine, and metanphetamine, opium alkaloids as thebaine, codeine, morphine and cocaine, vitamins such as vitamin A, vitamin D3, vitamin B12, and biotine (vitamin H). Methods of preparation and characterization of hapten-carrier protein conjugates, and the evaluation of their immunogenic properties are described in this paper. [ABSTRACT FROM AUTHOR]