Sequencing-based typing reveals six novel MHC class I chain-related gene B (MICB) alleles

Abstract: The MHC class I chain-related gene A (MICA) is highly polymorphic. In this paper we demonstrate polymorphism in the other expressing member of the MIC family of genes: MICB. Using a sequencing-based typing approach on cDNA, analysis of exons 2 through 6 revealed eight polymorphic sites resulting in six unique MICB sequences. Although MICB has high nucleotide homology with MICA, its polymorphism is restricted and at different sites compared to those in MICA.     

Analysis of functional epitopes on the dengue 2 envelope (E) protein using monoclonal IgM antibodies

Summary Forty-two hybridomas secreting IgM antibody against dengue virus were derived from spleen cells of dengue 2 infected mice. Antibody from 27 of these recognised the E protein of this virus. Of the 22 antibodies which neutralised dengue 2, only two cross-reacted with other flaviviruses. These 22 antibodies recognised three discrete domains on dengue virions. Competitive binding studies with IgG monoclonal antibodies suggested that two of the three domains were recognised by both IgG and IgM antibodies and that there were two additional domains which may be recognised exclusively by either IgG or IgM antibodies. IgM antibodies reacting with domains recognised by IgG antibodies that enhanced infection of susceptible cells by dengue 2, had no enhancing properties. None of the IgM antibodies activated the serum complement system after reacting with dengue 2 virions.     

Visual perception: double pulse temporal resolution. (Lack of contingency upon the phase of resting cardiac and respiratory cycle)

Double light pulse resolution required longer inter-pulse time intervals of short duration of the pulse. The threshold of double pulse discrimination was not contingent upon the actual phase of cardiac or respiratory cycle.     

Prevalence of antibody to current influenza virus strains in adolescents

During the Spring of 1986, 118 pupils aged 15-18 years were surveyed for the presence of humoral antibodies to five influenza strains. Prevalence of humoral immunity (HI) antibodies and immunity was found to be related to the year of the strain's emergence and to length of circulation time in the community. A high percentage of the adolescents were not immune to one or more of the tested strains. More than 40% of the studied group were not immune to the old A strains A/Philipines 2/82 (H3N2) and A/Chile 1/83 (H1N1), nearly 70% were not immune to the two B strains (B/USSR 100/83 and B/Ann Arbor 1/86), and almost the entire group (96%) was unprotected against the recent strain A/Singapore 6/86. Only one pupil was immune to all five strains; 35.6%, 22.2%, 17.8%, and 9.2% were immune to one, two, three, or four of the strains, respectively; and 14.4% were not immune to even one strain.     

Area under the viraemia curve versus absolute viral load: utility for predicting symptomatic cytomegalovirus infections in kidney transplant patients

A novel approach to predicting symptomatic cytomegalovirus (CMV) infections combines the level and the duration of viraemia in a single parameter. Sixty-four kidney transplant recipients were monitored by quantitative shell vial culture, pp65 antigenaemia, and polymerase chain reaction (PCR) of leucocytes. The area under the curve (AUC) of each parameter was determined from the onset of viraemia to the beginning of antiviral treatment. The AUC values were significantly higher in symptomatic than in asymptomatic patients. For antigenaemia and PCR, optimal AUC thresholds for predicting symptomatic CMV infections were determined. They were superior to standard cutoff levels of absolute viral load in sensitivity, specificity, and positive and negative predictive value. In 8 of the 23 patients who became symptomatic, impending clinical features were indicated earlier by the AUC thresholds than by standard viral load. In conclusion, the concept of the AUC should facilitate identification of patients at risk of symptomatic CMV infection.     

Assessment of the viability of haemopoietic cells in the livers of mouse fetuses stored at 4 degrees C. Comparison of various methods of testing their usefulness for haemopoietic transplantation

The usefulness of three different tests available in experimental haematology for the assessment of the viability of fetal liver cells obtained from murine fetuses kept in refrigerator at 4 degrees C was compared. The usefulness of these cells as potential transplants for haemopoiesis reconstitution was assessed in the test with trypan blue, in the test based on clonal growth of GM-CFU in agar, and in the test of the splenic colony forming ability of CFU-S. Fetuses kept in refrigerator at 4 degrees C tested 16 hours after circulation arrest contained still about 70% of the initial number of the haemopoietic stem cells (CFU-S). The proportion of committed cells belonging to the granulocyto-monopoiesis line (GM-CFU) decreased at the same time to about 25% of the initial number, and was a sensitive indicator of hypoxia of the studied organ. The test for the viability of the cells based on the use of trypan blue gave results reflecting better the changes in the number of CFU-S than GM-CFU cells.