Browsing by Author "Mathai, Jaisy"

Now showing 1 - 5 of 5
  • Item
    Expanding role of a blood center.
    (Asian journal of transfusion science, 2012)
    MATERIALS AND METHODS: The study was performed on prospective donors who reported to the Department of Transfusion Medicine. Individuals deferred due to hypertension contributed the study population. They were compared with age and sex matched donor controls. Demographic details were recorded in a proforma. On identification of a hypertensive individual, consequent two comparable donors were taken as controls with a total of 50 hypertensive subjects. Hypertensive status of the subjects were assessed based on the criteria formulated by the WHO-ISH and US Seventh Joint National Committee report on prevention, detection, evaluation and treatment of high blood pressure.RESULTS: About 0.95% of healthy blood donors had undetected hypertension. Mean age at detection of hypertension in the study group was 35.44 7.69 years. Higher BMI was observed in the hypertensive group compared to normotensive control group with P value significant at 0.0001.CONCLUSION: About 1% of healthy individuals were found to have undetected hypertension. Though the study was not designed to determine the prevalence of hypertension in the region, it is a rough estimate of the proportion of undetected hypertension in the local population as donors are considered as representative of healthy population.
  • Item
    High polymeric IgA content facilitates recognition of microbial polysaccharide-natural serum antibody immune complexes by immobilized human galectin-1
    (IMMUNOLOGY LETTERS, 2011)
    Dextran-binding immunoglobulin (Dig) and anti-beta-glucan antibody (ABG) are naturally occurring human serum antibodies specific to alpha- and beta-glucoside epitopes respectively of polysaccharide antigens and heavily enriched in IgA. ABG and Dig are shown here to have much more of their IgA in polymeric form than does serum IgA in general. Cell wall beta-glucans and glycoproteins of the widely consumed yeast (Saccharomyces cerevisiae) offered several hundred fold better ligands for ABG than did small beta-glucosides. Candida albicans cell wall antigen (CCA), a commonly encountered polysaccharide-rich fungal antigen was recognized by normal human serum anti-carbohydrate antibodies to precipitate maximally at a definite stoichiometry typical of immune complexes (IC). IC formed in serum in vitro on addition of CCA contained a significantly higher percentage of IgA than did either naturally occurring IC or serum. Polymeric IgA was far better ligand than monomeric IgA for both anti-IgA antibody and the most widely expressed human tissue lectin galectin-1 which recognizes O-linked oligosaccharides characteristic of IgA, in contrast to N-linked oligosaccharides present in all immunoglobulins. Moreover, desialylation by neuraminidase, an enzyme released into circulation during many microbial infections and diabetes, increased lectin-binding activity of polymeric IgA much more than that of monomeric IgA. Human galectin-1 immobilized in active form in vitro sugar-specifically captured IgA and IgA-containing IC formed by CCA in serum but not IgG. Results suggest that while high IgA content especially in polymeric form may render polysaccharide IC more susceptible to tissue uptake, desialylation of IgA in IC could enhance the process. (C) 2010 Elsevier B.V. All rights reserved.
  • Item
    Problem of bacterial contamination in platelet concentrates
    (TRANSFUSION AND APHERESIS SCIENCE, 2009)
    Bacterial contamination of blood is being recognized more frequently now and is one of the serious complications of transfusion. Use of integrally attached collection systems and strict standards for skin preparation, collection and storage of blood and components have reduced but not eliminated the risk of bacterial contamination. As bacteraemia may be part of acute or sub acute infections, strict donor selection is warranted. The longer the storage time, the greater is the number of organisms and amount of endotoxin present in the unit and associated with transfusion reactions. Importance of haemovigilance system and awareness among clinicians on the potential complications will go a long way in reducing patient morbidity. New approaches for detection of bacterial contamination, pathogen reduction and developments in the field of platelet biology will increase blood safety. (C) 2009 Elsevier Ltd. All rights reserved.
  • Item
    Profile of transfusion transmissible infections and associated risk factors among blood donors of Kerala.
    (Indian journal of pathology & microbiology, 2002)
    Blood transfusion is an important mode of transmission of infections to the recipient. The aim of the study was to assess the prevalence of transfusion transmissible infections and the possible risk factors among blood donors. During the study period (1994-99) donor samples were screened for HBsAg, HIV, HCV and Syphilis. The relevant donor history was examined to identify the risk factors leading to transfusion transmissible infections. The prevalence of infection was 3.1% among donors, with HBsAg constituting 1.3%, HCV 1.4%, HIV 0.2% and RPR 0.2%. In a classification based on occupation, class III donors (drivers, Businessmen & men in uniform) showed a significantly higher incidence of transfusion transmissible infections for HIV (0.38%) and Syphilis (0.36%). Health care workers constituted only a small fraction of the study; prevalence of infections was low among them. History of jaundice or hospitalization was not associated with higher incidence of seropositivity. Seropositivity for HIV is relatively low compared to similar studies conducted in other regions of the country. This finding is attributed to the pre donation counseling in donor selection. An important outcome of the study is that Class III donors form a high-risk group for transfusion transmissible infections.
  • Item
    Suitability of measurement of swirling as a marker of platelet shape change in concentrates stored for transfusion
    (PLATELETS, 2006)
    Platelet discoid shape is known to correlate with in vivo viability after transfusion. Measurement of shape change requires invasive sampling and laborious assays, which is difficult to perform in a blood transfusion center as a routine test for quality control of stored platelets. The objective of this study was to establish suitability of swirling assessment in stored platelet suspension as a routine test for quality check, by comparing platelet shape change measurement carried out in parallel. The study was done in two types of bags obtained from different manufactures (Groups 1 and 2). Platelet concentrates (PC) were stored for 120 h and samples drawn at 24-h intervals, optical analysis at 540nm was carried out to quantify shape change in response to an agonist adenosine diphosphate (ADP). The same bags were subjected to swirling assessment, by two blood bank personnel independently and graded as positive (+,++,+++) or as negative, based on the silky appearance of the suspension. Swirling negative platelets were prepared by storing platelets at 4 degrees C for 24 h and were compared with swirling positive platelets. Other parameters studied in the samples drawn at 24-h intervals were platelet count, mean platelet volume, and blood gases. Swirling assessment results correlated well with shape change measurement at each study period with a P value significant at 0.02 and 0.04 for group 1 and 2 bags, respectively. In the negative swirling controls, extent of shape change was lower than the extent in test bags, showing reduced capacity to respond to ADP at 4 degrees C. The results of the study indicate that by simple swirling measurements, stored PC can be monitored for loss of discoid shape before they are transfused. Gas tension and pH were with in permissible limits. Therefore, inspection of swirling can be a reliable method of quality control as it correlates with platelet function. The platelets that retain the discoid shape in vitro at the time of transfusion are expected to be functional in vivo.