Prevalence of anti HCV, HBsAg and HIV antibodies in high risk recipients of blood and blood products.

Along with hepatitis B virus (HBV) and human immunodeficiency virus (HIV), Hepatitis C virus (HCV) is emerging as a major transfusion hazard. 22 cases of haemophilia (A 19, B 3) and 20 cases of thalassaemia (2 16, E(2) 4) constituted the study group. Patients tested for anti HCV (using third generation ELISA), HBsAg and antibodies to HIV I and II. Prevalence of anti HCV was 54.5% in haemophilics and 5% in thalassaemics. HBsAg was detected in 9.09% haemophilics and 5% thalassaemics. No anti HIV was detected in this cohort. Anti HCV seropositivity in haemophilics has increased compare to previous studies.

The activity of superoxide dismutase in hydroxyurea-treated E beta thalassemia.

AIM: To study the activity of superoxide dismutase (SOD) and the level of fetal hemoglobin (HbF) in hydroxyurea (HU)-treated E beta thalassaemia. METHODS: We have measured SOD level, HbF, mean corpuscular volume (MCV), packed cell volume (PCV) and hemoglobin (Hb) of E beta thalassaemia treated with HU (dose 30 mg/kg/day) for consecutive 90 days. RESULT: The increase of HbF synthesis without increase of Hb was observed in HU-treated patients. CONCLUSION: The decreased SOD level in long term and low dose of HU therapy in E beta thalassaemia may have some role to inhibit superoxide radical of erythrocyte. HU may act as inhibitor for oxidative damage of red cell in E beta thalassaemia.

The prevalence of antiphospholipid antibodies in cases of recurrent pregnancy loss.

Antiphospholipid antibodies (aPL) are a diverse family of autoantibodies reactive against negatively charged phospholipid-protein complexes. The clinically significant members include lupus anticoagulant (LA), anticardiolipin antibody (aCL) and reaginic antibodies causing biological false positive (BFP) venereal disease laboratory test (VDRL). Although detected in various clinical scenarios, unexplained fetal loss in women of reproductive age group is the commonest association. Fifty pregnant women of first and second trimester with a history of two or more unexplained pregnancy losses were studied for the presence of LA, aCL and reaginic antibodies. Thirty pregnant women of the same trimester without any history of fetal loss were taken as control. LA was detected in nine (18%) cases and aCL in 12 (24%) cases of the study group. The control group was negative for any autoantibody. The prevalence of aPL in the study group found to be statistically significant. Detection of aPL must be considered in women with previous pregnancies complicated by unexplained fetal wastage.

Image contrast of biological macromolecules in electron microscopy under accelerated voltage.

Image contrast in the tilted beam mode of dark field (DF) imaging with a conventional transmission electron microscope has been estimated theoretically for two well-known biological macromolecules viz. lambda-phage DNA and BSA precursor protein. The DF contrast for electron accelerating voltage 0.1 to 3.0 MV has been compared with the corresponding bright field (BF) contrast. The DF contrast is seen to be so overwhelmingly greater than the BF contrast, for a wide range of accelerating voltage (phi) and aperture (alpha), that even an unstained bio-macromolecule should become visible under high voltage DF imaging.

O-acetyl sialic acid binding lectin as a probe for detection of subtle change on cell surface induced during acute lymphoblastic leukemia (ALL) and its clinical application.

A novel probe, a 9-O-acetylated sialic acid binding lectin, namely achatininH (ATNH) has been used for the detection of changes on the cell surface during acute lymphoblastic leukemia (ALL). ATNH does not agglutinate normal human erythrocytes, however it is capable of agglutinating erythrocytes and peripheral blood mononuclear cells (PBMC) of patients suffering from ALL. The differential expression of a key receptor, 9-O-acetylated sialo glyco conjugate (9-O-AcSG), on PBMC was observed using a simple lymphoproliferative assay (LA). The extent of expression of 9-O-AcSG was used as an index to distinguish ALL patients of different clinical stages and assess the probability of relapse. The amount of ATNH needed for maximum stimulation served as a tool to indirectly measure the extent of expression of 9-O-AcSG on PBMC surface. The acetylated sialo glycoconjugate was expressed at a very high concentration during acute phase of the disease. Subsequently it decreased during treatment persisted during maintenance therapy and reappeared with relapse. PBMC of normal human donors required 80 times more ATNH in comparison to the untreated acute phase ALL patients. No cross reactivity was found in non Hodgkin's lymphoma, chronic myelogenous leukemia and thalassaemia patients.

Human immunodeficiency virus infection related to blood transfusion service.

The prevalence of transmissible viruses, human immunodeficiency (HIV) and hepatitis B (HBV) in blood donors, recipients and blood bank staff in a Calcutta (eastern India) based blood bank and transfusion centre has been studied from 1987-93. HIV seropositivity of blood donors was of recent emergence and was low. Recipients of blood and blood components frequently i.e., haemophilics showed a progressive increase in HIV seropositivity since 1988 whereas in thalassaemics the emergence of HIV seropositivity was noted only in 1992. Blood bank staff were seronegative. HBV which has a similar portal of entry as HIV, had a higher prevalence in blood donors, recipients of blood/components and blood bank staff.

Hepatitis B vaccination and the rate of seroconversion in high risk contacts.

Twenty-seven employees of a blood transfusion centre, Calcutta were vaccinated with hepatitis B vaccine (recombinant DNA technology), 20 micrograms/1 ml intramuscularly on 0, 8, 32 weeks interval. The seroconversion rate at 8, 32, 40 weeks were 29.6%, 55.5% and 100% respectively. The recombinant hepatitis B vaccine is acceptable and safe. The seroconversion rate is comparable to plasma derived hepatitis B vaccine.

Immunosurveillance of transfusion dependent thalassaemia and hepatitis B vaccination.

The study evaluates the probable alteration of the immune system in multitransfused thalassaemics and the modification of their immune response following administration of hepatitis B virus (HBV) vaccine. B-thalassaemics (n = 50) and EB-thalassaemics (n = 30) who received multiple blood transfusion for the chronic anaemic status had significant iron overload. They had high prevalence for hepatitis B carrier state and almost all were exposed to hepatitis B virus during the course of transfusion as shown by the positivity of hepatitis B virus markers. Thalassaemics in presence of iron overload have altered immune status in terms of depressed T-lymphocytes and raised immunoglobulins G and M. However, they showed 100 per cent seroconversion with production of antibody to hepatitis B surface antigen following Hepatitis B vaccination.

Sero-surveillance of transmissible hepatitis B & C viruses in asymptomatic HIV infection in haemophilics.

In a group of 37 haemophilics, 9 (24.3%) were seropositive for human immunodeficiency virus (HIV), while 9 (24.3%) and 10 (27%) were positive for hepatitis B virus (HBV) and hepatitis C virus (HCV) respectively. Haemophilics who were HIV seropositive had higher prevalence of HBV and HCV. Seropositivity for HIV was more in patients with severe haemophilia A who required frequent factor VIII replacement. The need for long term surveillance of voluntary blood donors for transfusion associated viruses like HIV, HBV and HCV, is emphasized.

Prevalence of hepatitis C in transfusion dependent thalassaemics & haemophilics.

Seventy thalassaemics (B = 37, EB = 33) and 20 haemophilics (A = 18, B = 1, C = 1) were tested for antibodies to hepatitis C virus (anti-HCV) and markers for hepatitis B virus (HBV). The seropositivity for anti-HCV in thalassaemics and haemophilics was 14.3 and 25 per cent respectively. The subjects who were sero-positive to anti-HCV had had additional exposure to HBV. Anti-HCV positivity was not related to the age of the subject nor the number of units of blood and blood components transfused. Screening of blood donors for anti-HCV, apart from HBV, may minimise the hazards of post transfusion hepatitis in high risk recipients like transfusion dependent thalassaemics and haemophilics.

Prevalence of hepatitis B virus (HBV) markers and human immunodeficiency virus (HIV) in employees of a blood transfusion centre.

Blood bank staff, 8 out of 25 (32%) have been exposed to hepatitis B virus (HBV) and the prevalence of HBV markers in blood bank employees handling high risk subjects show hepatitis B surface antigen (n = 1), hepatitis B surface antibody (n = 7), hepatitis B core antibody (n = 6) and combined hepatitis B surface antibody and hepatitis B core antibody (n = 6) seropositivity but all are negative to human immunodeficiency virus (HIV). Serum alanine aminotransferase was raised in the employees than normal subjects and it is suggestive of sub-clinical hepatitis. The employees of blood bank should be trained for proper handling of test materials and must be periodically monitored for HBV and HIV. Immunisation for HBV is mandatory only for the employees of transfusion centre which handles high risk subjects.

Differential effect of retinoic acid on ADP and collagen induced platelet aggregation.

Retinoic acid (RA) was found to inhibit ADP induced but not collagen induced aggregation of human platelets and the differential action is related to intraplatelet Ca2+ reflux. RA was active at concentrations as low as 10(-7) M and required 20 min prior incubation with platelet suspension in order to inhibit aggregation by ADP. All the steps in ADP induced but not collagen induced platelet activation, viz. hydrolysis of phosphatidyl inositol, phosphorylation of 20, 47 and 250 kDa proteins as well as increased association of actin with Triton X-100 insoluble cytoskeletal matrix were inhibited by RA. RA when used as an agent for differentiation induction of cell progenitor is likely to affect the platelet aggregation and thereby the haemostatic process.

Effect of retinoic acid on adenosine diphosphate and collagen-induced alterations in enzymes of GSH-linked antioxidant defence system of human blood platelets in vitro.

Collagen stimulation of blood platelets resulted in significant increases in malondialdehyde (MDA) formation and activity of glucose-6-phosphate dehydrogenase (G6PDH) and a decrease in catalase and glutathione peroxidase (GPx). Retinoic acid (RA) pretreatment did not show any appreciable changes except for a decrease in G6PDH activity as compared with collagen alone. RA pretreatment of human blood platelets resulted in an increase in the activities of catalase and GPx, two important radical scavenging enzymes, with significant decrease in MDA formation when compared with ADP alone. It is suggested that RA has a significant effect on the antioxidant defence system in ADP stimulated platelets but not in the collagen stimulated platelets.

Blood donation and risk of post-transfusion hepatitis.

A survey was conducted among 300 blood donors of urban and rural population (the Sunderbans) and paid donors to evaluate the nutritional status, serum proteins, immunoglobulin and alanine aminotransferase (ALT) on the persistence of carrier state for post-transfusion hepatitis (PTH). Paid donors showed lowering of serum albumin and elevation of immunoglobulin and ALT. Nutritional and immunoglobulin profiles of rural donors of the Sunderbans, differed from those of voluntary donors of urban area. In the presence of subclinical hepatitis, ALT measurement alone is not a reliable guide for identification of individual carriers.

HBV & HIV seropositivity in multi-transfused haemophilics & thalassaemics in eastern India.

Seropositivity to HBV (HBsAg) in multi-transfused patients of haemophilia A, haemophilia B, B thalassaemia and EB thalassaemia from Eastern India, was found to be 9, 0, 22.1 and 13 per cent respectively. HIV seropositivity was detected in patients of haemophilia A (4.4%) and B thalassaemia (0.8%) who received plasma components and packed cells periodically. Seropositivity to both HBsAg and HIV was found in one patient of haemophilia A. Serum alanine amino transferase (ALT), raised in multi-transfused thalassaemics suggests concurrent hepatitis which might have enhanced the transmission of viruses due to disturbed immune status. The universal voluntary blood donation programme, screening of blood for HBV and HIV by sensitive tests, early immunisation and periodic monitoring of HBV and HIV status are prerequisites for the management of transfusion dependent thalassaemia and haemophilia.

Detection of haemophilia A traits in carriers.

Obligate carriers of haemophilia A and normal women matched for age were studied in order to find a suitable parameter for detection of carriers of haemophilia A. The ratio of factor VIII coagulant activities (F VIIIC) to factor VIII related antigen (F VIII R : Ag) was 0.55 in obligate carriers and 1.0 in non-carrier females.