CD23 exhibits negative regulatory effects on allergic sensitization and airway hyperresponsiveness.

The effects of an anti-CD23 monoclonal antibody (B3B4) in CD23-deficient and CD23-overexpressing mice were compared in a murine model of allergic sensitization. After sensitization and challenge with OA, mice developed increased serum levels of OA-specific IgE and IgG(1) with airway eosinophilia and AHR when compared with nonsensitized animals. Anti-CD23 treatment was studied under two protocols: 10-d OA aerosol exposure and intraperitoneal sensitization followed by aerosol challenge. In both protocols anti-CD23 significantly reduced IgE and IgG(1) levels, abolished eosinophilia, and normalized AHR in BALB/c and wild-type CD23+/+ mice but not in CD23-/- mice. These changes were associated with increases in IFN-gamma and decreases in IL-4 production, suggesting that CD23 binding may affect not only IgE production but also the Th1/Th2 imbalance during the development of allergic AHR. Absence of CD23 in gene-deficient mice significantly enhanced OA-specific IgE and IgG(1) levels, airway eosinophilia, and AHR when compared with CD23+/+ wild-type littermates after sensitization and airway challenge. Sensitized and challenged CD23 transgenic mice also developed eosinophilic airway inflammation and methacholine hyperresponsiveness. However, the extent of AHR, BAL, and tissue eosinophilia in these animals showed a significant negative correlation with levels of CD23 expression on splenic T and B cells, demonstrating a limiting role of CD23 in the development of allergic AHR.

Anti-CD86 (B7.2) treatment abolishes allergic airway hyperresponsiveness in mice.

Allergic sensitization in asthma develops as a consequence of complex interactions between T cells and antigen-presenting cells. We have developed several in vivo models to study allergen-specific T cell and B cell function and their relevance to allergic airway hyperresponsiveness (AHR), focusing on the role of the costimulatory molecules CD80 and CD86. Treatment of mice with anti-CD86, but not anti-CD80, significantly inhibited increased serum levels of ovalbumin (OA)-specific IgE and IgG1, airway eosinophilia, and AHR both after 10 d of OA aerosol exposure (in the absence of adjuvant) and after intraperitoneal sensitization followed by repeated airway challenges. Inhibition of AHR was associated with decreased IL-4 and IL-5 levels in the BAL fluid of sensitized mice, suggesting impaired Th2 function in anti-CD86-treated animals. This effect was not seen when mice received treatment only before allergen challenge, indicating that anti-CD86 acts through inhibition of allergic sensitization and not simply by inhibiting the influx of inflammatory cells. These data suggest that the CD86 costimulatory ligand plays a major role in the development of allergic inflammation and AHR in allergen-challenged mice. Further, this study demonstrates that T-B cell interactions during allergic sensitization are amenable to therapeutic manipulation and that selective blockade of accessory signals can be an effective means for modulating distinct T cell functions.

Is rocuronium an exception to the relation between onset and offset? A comparison with pipecuronium.

A general relation between the rate of onset and rate of recovery from non-depolarizing blockade has been demonstrated, with recovery consistently about ten times slower than onset. This observation has led to the suggestion that non-depolarizing agents share a common mechanism of action. Rocuronium, a recently introduced steroidal non-depolarizing agent, is claimed to have a very rapid onset but an intermediate duration and appears to test this hypothesis. To investigate this paradox we have calculated the rates of onset and recovery of rocuronium using the isolated human forearm and compared them with those of pipecuronium. The mean ratio of recovery time/onset time for rocuronium was 31.3, which is significantly greater than that for pipecuronium, 11.6 (P < 0.01). Whilst pipecuronium conforms to the same general relation between onset and offset described previously for other non-depolarizing agents, rocuronium appears to have a disproportionately rapid rate of onset for its rate of recovery. This suggests that onset, recovery, or both onset and recovery, from rocuronium blockade occur in a different manner to that of other non-depolarizing agents.

The influence of cold on the recovery of three neuromuscular blocking agents in man.

The Arrhenius hypothesis suggests that change in temperature has a less marked effect on the rate of physical processes than on biological reactions. We have investigated the process underlying recovery from neuromuscular block in man by studying the effect of cooling on the rate of recovery from depolarising and non-depolarising block. Vecuronium, rocuronium and decamethonium (C10) neuromuscular block were investigated using the isolated forearm technique on awake human volunteers. In these experiments, one arm was cooled whilst the other was used as control. Moderate hypothermia decreased the rate of recovery from all three agents, but this was significantly less marked with the depolarising drug. The mean Q10 (the anticipated change in rate of a reaction across of 10 degrees C temperature gradient) of the rate of recovery for vecuronium was 3.21, rocuronium 2.86 and decamethonium 1.29. This suggests a different process in the recovery of these two types of drug. According to the Arrhenius hypothesis this would suggest that the recovery from non-depolarising drugs is likely to involve a biochemical mechanism and that recovery from decamethonium is controlled by a physical process.

Interaction of decamethonium with hexamethonium or vecuronium in the rat: an isobolographic analysis.

We used isobolographic analysis to investigate the interaction of decamethonium with either hexamethonium or vecuronium in the rat phrenic nerve hemidiaphragm preparation. EC50 values of decamethonium, hexamethonium, and vecuronium were (mean +/- SEM) 47.36 +/- 9.58 microM, 4.27 +/- 0.53 mM, and 5.19 +/- 1.17 microM, respectively. Combinations of drugs in concentrations corresponding to the 1:2, 1:1, and 2:1 ratios of their EC50 values were used to determine three points of each isobole. Decamethonium and hexamethonium showed antagonism: significant deviations from the line of additivity were found at EC50 ratios of 2:1 and 1:1 (P < 0.01 and P < 0.05, respectively) indicating that hexamethonium is a potent antagonist of decamethonium. For decamethonium and vecuronium none of the three points on the isobole was significantly different from the corresponding point on the line of additivity. Hexamethonium is known to be a weak antagonist at the postsynaptic nicotinic acetylcholine receptor but a potent antagonist at the presynaptic nicotinic receptor. Vecuronium is a more potent antagonist at the postsynaptic nicotinic receptor but a much weaker antagonist at the presynaptic site. It was postulated that in the rat the primary site of action of decamethonium is at the presynaptic nerve terminal. Our findings suggest that presynaptic rather than postsynaptic potency of a nondepolarizing drug determines ability to antagonize the effect of a depolarizing drug in the rat.

Priming studies with rocuronium and vecuronium.

We studied the effects of rocuronium and vecuronium as priming agents before both vecuronium and rocuronium neuromuscular blockade. Rocuronium is ineffective at priming rocuronium. Vecuronium is effective at priming rocuronium, producing an approximate 33% reduction in onset time. Rocuronium and vecuronium, when given as priming agents, both reduce the onset time of vecuronium block.

Clinical significance of amniotic fluid bacteriological cultures taken at caesarean section.

To predict postoperative infection after Caesarean section by bacteriological examination of amniotic fluid samples a prospective analysis was performed on amniotic fluid bacteriological results and infectious morbidity in 266 consecutive Caesarean sections. Culture and sensitivity results were analysed in relation to postoperative febrile complications and their antibiotic treatment. One hundred and twelve samples grew bacteria. There was a significantly higher frequency of postoperative pyrexial complications among those patients with a positive amniotic fluid culture (22.3% vs 14.2%). Eighty per cent of amniotic fluid samples with significant bacterial growth provided useful information when antibiotic treatment had been required. Routine amniotic fluid sampling for bacteriology at Caesarean section is of clinical value in the prediction and management of postoperative pyrexial complications.

[Experience with peflacine in the treatment of osteomyelitis]. / Péflacine-nal szerzett tapasztalatok csontgennyedések kezelésében.

Authors report on the treatment of 20 chronic osteomyelitis patients in whom direct antibiotic therapy was performed using the preparation Péflacine. The infected area was exposed in every case, the bony focus was excised and the wound was drained. During the operation, as an induction 800 mg Péflacine in slow drop infusion was given. Oral preparation (2 x 400 mg/die) followed, and was continued for 30 days. The secretion of the wounds ceased in every case, after 3 weeks the latest. In 2 cases mild gastrointestinal symptoms as side effects were observed. Relapse the first time occurred 5-7 months after ending the treatment in 3 patients. These were again explored and after the excision more thorough than before the secretion ceased. According their experience and in conformity with the literature the Péflacine is held an effective medicament in the treatment of the acute exacerbation of chronic osteomyelitis, together with the excision of the focus.

A comparative study on growth in soft-agar, adherence to glass and haemolysis types of coagulase-negative staphylococci.

Growth properties of coagulase-negative staphylococci in the presence and in the absence of human and rabbit serum in soft-agar prepared in modified Staphylococcus 110 broth were studied. The adherent growth was examined in modified Staphylococcus 110 broth and 1% glucose-meat broth. Of 100 strains examined 69% exhibited diffuse, 18% compact, 7% transient and 6% mixed growth. Compact type colonies were mainly characteristic of Staphylococcus haemolyticus strains. The presence of serum failed to influence the types of colony morphology in any of the strains. Sixty-three percent of the strains showed adherent growth; none of the S. haemolyticus strains produced adherent growth. The glucose-meat broth, unlike modified Staphylococcus 110 broth, was suitable to study adherence. The coincidence of the compact colony morphology in soft-agar and the absence of adherent growth seems to be a taxonomic sign for the species S. haemolyticus and differentiate it from the species Staphylococcus epidermidis.

[Effect of acute aprotinin (Gordox) therapy on hemostasis in heart surgery patients, with special reference to hyperfibrinolysis]. / Az akut aprotinin (Gordox) terápia hatása a haemostasisra szívsebészeti betegekben, különös tekintettel a hyperfibrinolysisre.

Authors have studied the effect of Gordox-therapy on haemostasis after open heart surgery in a prospective clinical trial. Thirty seven patients (pts) undergoing cardiac surgery due to their valve disease were randomly assigned either to control-group (20 pts) or to Gordox-group (17 pts). The patients in the Gordox group were given Gordox according the following scheme: 2 M IU within 20 min. after induction of anaesthesia followed by 0.5 M IU/hour infusion until the end of the operation. One M IU also was given into the oxygenator before starting the extracorporeal circulation. The postoperative chest tube drainage was less in Gordox-group (534 +/- 260 ml vs. 987 +/- 583 ml, p less than 0.005), and donor blood and fresh frozen plasma requirement was also lower in this group (534 +/- 633 ml vs. 935 +/- 718 ml p less than 0.05; 70 +/- 153 ml vs. 211 +/- 245 ml p less than 0.05, respectively). There was no significant difference between the two groups concerning the postoperative activated partial thromboplastin time, prothrombin time, thrombin time values. The authors could document significantly higher fibrinogen concentration and significantly lower fibrinolytic activity postoperatively in the Gordox-group (p less than 0.05). Gordox therapy has advantageous effect on haemostasis after open heart surgery which can be documented both by clinical and laboratory examination.

Light-induced permeabilization and merocyanine 540 staining of mouse spleen cells.

Merocyanine 540 (M540) is a potential-sensitive, hydrophobic dye that preferentially incorporates into the 'fluid' domains of cellular membranes, distinguishing between hemopoietic cells according to their differentiation state. A bright staining with M540 is usually achieved by UV illumination of the cells during staining. We show by flow cytometric analysis that: (1) staining is greatly enhanced by UV illumination of mouse spleen cells before addition of the dye; (2) UV treatment causes an increased permeability toward propidium iodide and intracellular fluorescein as well; (3) the increment in M540 fluorescence precedes permeabilization to propidium iodide, while the latter precedes leakage of fluorescein. We also describe an overshoot and accelerated recovery of M540 fluorescence after photobleaching by a 514 nm laser beam. It is suggested that penetration of M540 to the more fluid inner membrane structures explains the fluorescence increment in both experiments.

[Effect of neutral red on the cytotoxic activity of olivomycin]. / Vliianie neitral'nogo krasnogo na tsitotoksicheskuiu aktivnost' olivomitsina.

Olivomycin accumulation in living cells first of all occurs in the cytoplasm or probably the cell lysosomes. The nuclear fluorescence of the cells incubated in olivomycin solution was observed in 60-90 minutes. Simultaneously with the nuclear fluorescence there was observed disappearance of the cytoplasm fluorescence. Intensive nuclear fluorescence was recorded in 15-30 minutes in 60-70% of the cells incubated in a solution of neutral red and subsequently treated with olivomycin. The amount of olivomycin bound to the nuclear DNA in dead cells in the presence of Mg++ and at pH 7.2 was so high that the cell nuclei produced yellow-green fluorescence. No binding of olivomycin to the nuclear DNA was observed in acid media. The cytotoxic activity of olivomycin after incubation with the human fibroblasts in a solution of neutral red increased 100 times. Olivomycin may be used for determination of vital activity of the cells when their lysosome function is not impaired.

Lysosomal acridine orange uptake in fibroblasts transformed by SV40 or human cytomegalovirus.

Lysosomes of living human fibroblasts, SV40-transformed rat fibroblasts and human CMV-transformed hamster fibroblasts were examined by fluorescence microscopy after pretreatment with acridine orange at a supravital concentrations (5 x 10(6) M). Dye uptake by human primary fibroblast lysosomes was considerable and independent of the age of the cultures. In the transformed cultures, cytoplasmic granular red fluorescence indicating lysosomal acridine orange uptake could not be observed in part of the cells; cells showing no cytoplasmic granular fluorescence appeared as early as after 48 hr incubation and were growing in dependence on the age of the culture. Staining of living cells by acridine orange solutions at supravital concentration is a practicable method for the examination of functional changes of lysosomes.

Changes in the intramembrane viscosity of sheep erythrocytes in the presence of membrane bound proteins.

Some dynamic properties of protein- and antibody-treated cell membranes were investigated. The membrane viscosity of sheep erythrocytes increased upon binding various proteins as determined from the fluorescence emission anisotropy of 1,6-diphenyl 1,3,5-hexatriene dissolved in the membranes. However, specific, IgM type immunoglobulins produced against the erythrocytes decreased the intramembrane viscosity of cells. The applicability of the above dye to follow the binding of specific and non-specific proteins to erythrocytes is also discussed.

Induction of lymphomas by urethane in combination with diethylstilboestrol in CFLP mice.

The combination of urethane and the non-steroidal oestrogen diethylstilboestrol induced lymphomas in CFLP mice.

Inhibition of rosette formation of IgE-bearing rat mast cells by disodium chromoglycate.

The interaction of reaginic antibody with specific antigen was studied by the rosette formation of peritoneal rat mast cells. The mast cells were obtained from actively sensitized rats or were passively sensitized in vitro. Rosette formation was of a higher degree with mast cells of actively sensitized rats; in this case 58% of the cells showed a strong rosette-forming effect (blinding more than 5 SRBC). No rosette formation was detected in 18% of the cells. With passively sensitized rat mast cells, rosette formation was 45% and 22%, respectively. Rosette formation of both actively and passively sensitized mast cells could be inhibited by disodium chromoglycate (DSCG); the inhibitory effect of 20 micrograms and 200 micrograms of the drug was the same, and neither dose caused a full inhibition. It is suggested that the linkage of specific antigen to the surface of sensitized mast cells can be inhibited by DSCG in vivo.