Differentiation of Strains of Infectious Bovine Rhinotracheitis Virus by Neutralization Kinetics with Late 19S Rabbit Antibodies

Two vaccine, two respiratory (infectious bovine rhinotracheitis [IBR]), and two genital (infectious pustular vulvovaginitis [IPV]) strains of infectious bovine rhinotracheitis virus were compared by neutralization kinetics using late 19S antibody (AB). The two vaccine strains were indistinguishable from one another, but were neutralized far more rapidly than the other four strains when either anti-IBR or anti-IPV 19S AB was used. The two IPV strains were indistinguishable from one another, but were neutralized significantly more rapidly than the two IBR strains when anti-IBR 19S AB was used. The 2 IBR strains were neutralized at a similar rate with the latter globulin preparation. Almost identical results were obtained with anti-IPV 19S AB, except that one IPV strain was neutralized at a rate similar to the IBR strains. However, when early and late rabbit 7S AB were used, IBR strains could not be distinguished from IPV strains by neutralization kinetics. Preliminary experiments indicated that both early and late 19S rabbit antibodies neutralized the homologous strain more rapidly than the heterologous strain, but the difference was more noticeable with late 19S AB. It was also determined that neutralization of IBR-IPV virus by specific early and late 19S rabbit AB and early 7S rabbit AB was markedly enhanced by guinea pig complement. Neutralization of this virus by late 7S AB, however, was only slightly enhanced by complement. These results suggest that vaccine strains of IBR-IPV virus may be distinguished by neutralization kinetics with late 19S rabbit AB, and that genital and respiratory strains may possibly also be distinguishable with some 19S AB preparations.     

Anxiety psychopathology predictive of outcome in patients with panic disorder and depression treated with imipramine, alprazolam and placebo

This study examines clinical predictors of outcome for patients with panic disorder and depression in a 16 week, placebo-controlled trial of alprazolam and imipramine (n = 126). Baseline global severity of illness and phobic avoidance were differentially predictive of acute response to treatment. Patients in the mild to moderate range of global distress experienced smaller degrees of improvement on alprazolam than on imipramine at week 4. At endpoint, the relative effectiveness of the active medication versus placebo was diminished in patients with higher levels of phobic avoidance. This relationship was not evident for completers, suggesting that the adverse effects of avoidance on outcome after sustained treatment was reduced.     

A longitudinal and prospective study of Epstein-Barr virus load in AIDS-related non-Hodgkin lymphoma.

BACKGROUND: Epstein-Barr virus (EBV) may be causally associated with non-Hodgkin Lymphoma (NHL) in HIV-infected patients. OBJECTIVES: To compare EBV load in whole blood in AIDS-NHL patients, HIV non-AIDS patients and non-HIV-infected persons, and to prospectively measure EBV load in whole blood in AIDS-NHL patients. STUDY DESIGN: Longitudinal and prospective study. RESULTS: We observed no statistical difference in EBV load between AIDS-NHL (3.69log(10) copies/mL [interquartile range (IQR): 2.89-4.27]) and HIV non-AIDS patients (3.08log(10) copies/mL [IQR: 1.29-3.57]) but AIDS-NHL patients had significantly higher EBV loads than HIV-negative controls (1.19log(10) copies/mL [IQR: 0.00-3.29]). We noticed an inverse correlation between CD4+ lymphocytes count and EBV load in patients with AIDS-NHL (r(2)=0.41, P=0.01). In the longitudinal study, the mean EBV load three months after NHL diagnosis decreased significantly (mean difference=-1.69log(10) copies/mL [95% confidence interval: -0.32; -3.04]; P=0.03) under chemotherapy but was still elevated in patients with relapses or no response to chemotherapy. CONCLUSION: Although EBV load seems a suboptimal marker for the diagnosis of AIDS-NHL, we observed a significant decrease of EBV load in patients treated with chemotherapy and a strong association between NHL outcome and EBV load in whole blood.     

The early phase of experimental acute renal failure

Experiments were conducted to establish whether diminished solute reabsorption in the loop of Henle during acute renal failure could explain the loss of urinary concentration and participate in generating a tubuloglomerular feedback-mediated reduction in filtration rate. The electrolyte content of the fluid in the ascending limb of the loop of Henle was determined in situ by monitoring its electrical conductivity after propulsion into the distal tubule with a sudden burst perfusion. The value of the minimum electrolyte concentration decreased exponentially with increasing equilibration time, reaching a steady-state value equivalent to 27±9 mM NaCl in normal kidneys, 34±15 mM in mercuric chloride kidneys and 53±22 mM following ischaemia. A mathematical model was derived to describe the process of sodium chloride dilution from which it was possible to calculate both the permeability and transport velocity of the cortical thick ascending limb. In the normal kidney, the transport velocity was calculated to be 4.65±0.92 ·10^–5 cm/s, a value not significantly different from that of the mercuric chloride or ischaemic kidneys, and the estimated permeability was 1.13±0.52·10^–5 cm/s, not different from that of the mercuric chloride kidneys but significantly lower than that calculated for the ischaemic kidneys. It is concluded that for the more severely damaged ischaemic model, the loss of urinary concentrating ability was accompanied by a reduction in diluting ability of the ascending limb of the short loop of Henle, which appears to be due, at least in part, to an elevation of the passive permeability to sodium chloride in this segment.     

A proposed autacoid mechanism controlling mastocyte behaviour

Evidence is provided here supporting the existence of a novel autacoid mechanism negatively modulating mast cell behaviour in response to noxious stimuliin vivo; hence, the denomination “autacoid local inflammation antagonism” (ALIA). In particular, as lipid amides of theN-acylethanolamine type have been reported to accumulate in tissues in degenerative inflammatory conditions, we examined whether theseN-acylated lipids could exert regulatory effects on mast cell activationin vivo. The results reported show that both long- and short-chainN-acylethanolamines, when systemically administered, are effective in reducing mast cell degranulation induced by local injection of substance P in the earpinna of developing rats. These and other data suggest that the endogenous production ofN-acylethanolamines may constitute a local autocrine/paracrine response for the negative feedback control of mast cell responses to various activating signals. Such a process may be of physio-pathological relevance in the regulation of functional neuroimmune-mast cell interactions.

     

Electron microscopy of the red pulp of human spleen

Terminating arterial vessels, the structure of sinuses and cords, and the passage of cells through the sinus wall in the red pulp of human spleen were studied. All terminating arterial capillaries arterial capillaries observed opened into cords. The distance between terminating arterial capillaries and sinuses varied. Macrophages were commonly present at arterial terminations. Arterial capillary endothelium contained filaments about 80 Å in diameter. Blood cells were frequently present in the capillary lumen or in passage through the capillary wall into cords. Endothelial cells of sinuses contained three distinctive structures: loosely organized cytoplasmic filaments, tightly organized finer filaments, and micropinocytotic vesicles. Many micropinocytotic vesicles about 0.1 μ in diameter were present just beneath the plasma membrane of the lateral and luminal sides of sinus endothelial cells and a few at the basal aspect. Loosely organized filaments about 80 Å in diameter ran parallel to the longitudinal axis of the sinus endothelium. The finer filaments about 30–50 Å in diameter were tightly organized as filamentous bands and present basally. The filaments of the bands appeared inserted upon the plasma membrane. They were also present in the cordal reticular cells and terminating arterial capillaries. Free cells were frequently present in passage through the slits of the sinus wall. There were no preformed or fixed apertures in the sinus wall. The basement membrane and reticular fibers were completely covered by the endothelial cells and/or cordal reticular cells. It is likely that those slits between endothelial cells in the sinus wall not covered by the basement membrane are potential passageways for cells moving from the cords into the sinus. The larger cytoplasmic filaments are likely contractile. The filamentous bands appear to maintain cell shape, stabilize the wall in relation to the basement membrane, and are probably operative in the control of cellular passage through the slits of sinus wall.