LFA-1 adhesion molecules are not involved in the early stages of HIV-1 env-mediated cell membrane fusion.

A recently developed sensitive assay to examine the early stages of HIV-1 env-mediated cell fusion is based on the redistribution of fluorescent dyes between membranes and cytoplasm of adjacent cells, monitored by fluorescence video microscopy. This assay demonstrated that membrane fusion can occur under conditions where no syncytia are formed. Fusion started earlier than syncytia formation and was not very sensitive to HIV-1 env+/CD4+ cell ratios. In the current study, this assay was used to determine the role of LFA-1 in HIV-1 env-mediated membrane fusion and syncytia formation. CD4- LFA-1- Epstein-Barr virus transformed lines from two leukocyte adhesion deficiency patients were infected with recombinant vaccinia expressing gp120/41 (HIV-IIIB), and cocultured with CD4+ subclones of the human T cell line CEM, which were generated by chemical mutagenesis and express either normal (LFA-1+), or low levels of LFA-1 (LFA-1lo). It was found that the LFA-1lo T-cell clone formed much smaller and fewer syncytia compared to the LFA-1+ subclones, but both clones fused equally well with the gp120/41 expressing LFA-1- B cells as monitored by redistribution of fluorescent dyes. Furthermore, monoclonal antibodies against the LFA-1 molecules reduced the number of syncytia formed but had no effect on membrane fusion. These findings demonstrate that the adhesion molecule LFA-1 does not play a crucial role in the early events of HIV-1 env-mediated cell membrane fusion, but may contribute to the later events leading to giant cell formation.     

Urosepsis. Clinical aspects--therapy--results.

Nine cases of urosepsis registered between 1986 and 1990 are analyzed. Authors intended to find out practical conclusions which can improve the prognosis of urosepsis. Risk factors are considered advanced age, preoperative disorders (diabetes, malnutrition), preexistent end organ failure (kidney, liver, lung) and urinary infection. Early diagnosis, emergency restoration of urinary flow, suppression of primary focus of infection, intravenous antibiotherapy and energetic intensive care measures are necessary for the outcome of patients.     

Physicochemical properties and restriction maps of simian adenovirus type 38 DNA.

The sedimentation constant of simian virus type 38 (SV-38) DNA was estimated to be 31.6S. The intrinsic viscosity of DNA was on average 86.5 dl/g and the length of the molecule determined by electron microscopy was 10.6 micrometer. The average mol. wt., as determined by sedimentation and viscometry, was 21.5 x 10(6), which agreed well with the value derived from the length of the molecule (21.4 x 10(6)) and with the value of 21.2 x 10(6) determined by the relative electrophoretic mobility of the DNA fragments produced by restriction endonucleases EcoR1, SalI and BglII. The buoyant density of the DNA in caesium chloride and casesium sulphate was 1.7185 and 1.4295 g/ml respectively. The melting temperature of the DNA in 1 x SSC was 93.5 degrees C. The GC content calculated from p and Tm values was 59.3%. BglII cleaves SV-38 DNA at three sites producing four fragments with mol. wt.: A, 9.3 x 10(6), B, 5.6 x 10(6), C, 3.3 x 10(6); and D, 2.9 x 10(6). After treatment with EcoR1 and SalI, SV-38 DNA is cleaved into five and six fragments respectively, with mol. wt. for EcoR1 fragments: A, 8.2 x 10(6), B, 6.5 x 10(6), C, 4.0 x 10(6), D, 1.27 x 10(6); and E, 1.07 x 10(6), and for SalI fragments: A, 6.5 x 10(6); B, 5.4 x 10(6); C, 4.2 x 10(6), D, 2.8 x 10(6); E, 2.5 x 10(6) and F, 0.25 x 10(6). The sequence of fragments within the SV-38 DNA molecules for BglII was deduced to be BDCA, and for ECOR1--BCEAD.     

Experimental and clinical analysis with the reconstruction of the fenestrated anterior wall of the sinus maxillaris

A comparative macroscopie and hystomorphological analysis of shutting the fenestrated front wall of the maxillary sinus is done with 34 rabbits. An autogenic bony cover and grates made of chromium cobaltomolybdenum and non-coloured plastic. Are used 30 patients are operated on with the same materials with tracing the process of reparation and the aeration of the operated sinuses. The results are compared with another group of patients operated without a reconstruction of the facial bony defect. The importance of reconstruction for reparation of the ventilation ability of the operated sinuses in the after-operational period is proved.