To determine passive haemagglutination (PHA) antibody titer that would protect chicks against Nigerian isolates of the Infectious Bursa Disease Virus (IBDV), five groups of chicks aged 30 days which had different anti...To determine passive haemagglutination (PHA) antibody titer that would protect chicks against Nigerian isolates of the Infectious Bursa Disease Virus (IBDV), five groups of chicks aged 30 days which had different antibody titers were challenged with a Nigerian isolate of virulent IBDV. Mortality rates of the different groups were plotted against their respective mean PHA antibody titers. A group with zero antibody titer had a mortality rate of 75% while those with PHA antibody titers of 185.6, 243.2, 256 and 307.2 had mortality rates of 40%, zero, zero and zero respectively. Linear equation generated for a line of best fit of the graph of mortality rates of the chicks on their IBD antibody titers gave antibody titer (X) at which mortality (Y) would be zero as 300. A mortality of 75% and the high antibody level needed to protect chicks suggest that the isolate may be a hypervirulent strain.展开更多
An inexpensive and rapid test for determining titers of Human Immunodeficiency Virus (HIV) in plasmas was developed. Washed sheep red blood cells were applied onto HIV positive plasmas, in V-bottomed microtiter plates...An inexpensive and rapid test for determining titers of Human Immunodeficiency Virus (HIV) in plasmas was developed. Washed sheep red blood cells were applied onto HIV positive plasmas, in V-bottomed microtiter plates, to complement the HIV antigens and antibodies present in plasmas. The setup was incubated for 30 minutes at 37℃. Reciprocal of the highest dilution of each plasma which gave passive agglutination of the RBCs was read as its HIV titer. Mean HIV load of five samples, was ≥ 4096.00 ± 0.00 after one day of storage at 4℃ but it reduced to 256.00 ± 70.10, 28.80 ± 3.20, 7.20 ± 0.80 and 1.60 ± 0.98 on days 2, 3, 4 and 7, respectively. HIV antibodies were still detectable, by ELISA, in plasma dilutions that were tested negative with the new test. It was concluded that when HIV antibodies have been confirmed, or added to plasmas, passive hemagglutination test can be applied to assess their viral loads.展开更多
文摘To determine passive haemagglutination (PHA) antibody titer that would protect chicks against Nigerian isolates of the Infectious Bursa Disease Virus (IBDV), five groups of chicks aged 30 days which had different antibody titers were challenged with a Nigerian isolate of virulent IBDV. Mortality rates of the different groups were plotted against their respective mean PHA antibody titers. A group with zero antibody titer had a mortality rate of 75% while those with PHA antibody titers of 185.6, 243.2, 256 and 307.2 had mortality rates of 40%, zero, zero and zero respectively. Linear equation generated for a line of best fit of the graph of mortality rates of the chicks on their IBD antibody titers gave antibody titer (X) at which mortality (Y) would be zero as 300. A mortality of 75% and the high antibody level needed to protect chicks suggest that the isolate may be a hypervirulent strain.
文摘An inexpensive and rapid test for determining titers of Human Immunodeficiency Virus (HIV) in plasmas was developed. Washed sheep red blood cells were applied onto HIV positive plasmas, in V-bottomed microtiter plates, to complement the HIV antigens and antibodies present in plasmas. The setup was incubated for 30 minutes at 37℃. Reciprocal of the highest dilution of each plasma which gave passive agglutination of the RBCs was read as its HIV titer. Mean HIV load of five samples, was ≥ 4096.00 ± 0.00 after one day of storage at 4℃ but it reduced to 256.00 ± 70.10, 28.80 ± 3.20, 7.20 ± 0.80 and 1.60 ± 0.98 on days 2, 3, 4 and 7, respectively. HIV antibodies were still detectable, by ELISA, in plasma dilutions that were tested negative with the new test. It was concluded that when HIV antibodies have been confirmed, or added to plasmas, passive hemagglutination test can be applied to assess their viral loads.
