Ethanol suppresses functions of the polymorphonuclear leukocyte (PMNL), seriously compromising normal host defenses against pneumonia. Because granulocyte colony-stimulating factor (G-CSF) augments the number and function of PMNL, the effect of G-CSF on the antibacterial defenses of the lung in normal and acutely intoxicated rats was studied. Animals received G-CSF or vehicle twice a day for 2 days, then ethanol or saline, followed by challenge with Klebsiella pneumoniae. K. pneumoniae elicited an intrapulmonary influx of PMNL in control rats that was markedly suppressed by prior ethanol administration. G-CSF augmented the recruitment of PMNL into the lungs of control rats and significantly attenuated the adverse effects of ethanol on PMNL entry into the lung. G-CSF enhanced intrapulmonary bactericidal activity against this pathogen in normal and ethanol-treated rats. All intoxicated rats pretreated with the vehicle died, while greater than 90% of rats pretreated with G-CSF survived. These findings suggest a potential role for G-CSF in mitigating the adverse effects of ethanol on PMNL delivery and pulmonary host defenses.

We have presented a retrospective study of 129 patients with platelet counts of 1,OOO X 109/L or more-72 with myeloproliferative disorders (MPD), and 57 with reactive thrombocytosis (RT)-in an effort to determine the incidence of thrombohemorrhagic complications. Thrombotic disorders occurred with approximately equal frequency in the two groups, being found in three patients (4%) with MPD and three (5%) with RT when the platelet count was over 1,OOO X 109/L and in 11% of the patients in each group when the platelet count was less than 1,OOO X 109/L. In contrast, bleeding manifestations were more common in MPD, where 36% of patients were affected on one or more occasions versus only 4% of those with RT. However, bleeding was generally not severe, with only six patients requiring transfusions, and three of these patients had been receiving aspirin or corticosteroids when they developed severe gastrointestinal bleeding.

No abstract

The effect of G-CSF pretreatment on experimental acute lung injury was studied in Sprague-Dawley rats receiving one of the following treatments: (1) G-CSF 50 micrograms/kg subcutaneously twice daily beginning 2 d prior to being killed; (2) ANTU 50 mg/kg intraperitoneally; (3) ANTU+G-CSF 50, 25, or 12.5 micrograms/kg; (4) HCl 0.6 ml of a 0.1 N solution intratracheally; (5) HCl+G-CSF 50 or 25 micrograms/kg; (6) control solutions. Lung injury was quantified by measurement of lung wet/dry weights, by histopathologic scoring, and by measurement of fluid flux during ex vivo perfusion. G-CSF pretreatment elevated the baseline blood neutrophil counts as much as 6-fold compared with Control, and it increased the numbers of lung neutrophils and caused a mild histologic lung injury, but it did not significantly alter wet/dry weight ratios or fluid flux. ANTU alone and HCl alone caused a moderate histologic lung injury, increased wet/dry weight ratio, and resulted in a small increase in flux. The combination injuries, ANTU+G-CSF and HCl+G-CSF, caused a more severe lung injury manifested by increased wet/dry weight ratios and increase in flux when compared with ANTU alone and HCl alone, respectively. We conclude that pretreatment with G-CSF potentiates ANTU- and HCl-induced lung injury in non-neutropenic rats. The potential for G-CSF to aggravate acute lung injury in patients remains speculative.

No abstract

After the intravenous injection of recombinant human tumor necrosis factor (TNF)-alpha (6.0 x 10(5) U) into rats, phorbol 12-myristate 13-acetate (PMA)-stimulated superoxide anion (O2-) secretion was enhanced in suspensions of alveolar macrophages (AM phi) compared with saline-treated controls. No enhancement of spontaneous, A23187-stimulated, or opsonized zymosan (OPZ)-stimulated O2- release was observed. Intratracheal injection of TNF-alpha (6.0 x 10(5) U) did not result in enhancement of spontaneous or A23187-, OPZ-, or PMA-stimulated O2- release. Although no TNF-alpha was detected in the bronchoalveolar lavage fluid, small quantities of TNF-alpha and/or other mediators secreted by polymorphonuclear leukocytes present in the lung capillaries, veins, and arteries may have leaked into the alveolar compartment and primed AM phi for enhanced PMA-stimulated O2- release. The respiratory burst in macrophages and neutrophils appears to be dependent on the translocation of protein kinase C. We have demonstrated protein kinase C translocation in both TNF-alpha- and saline-treated AM phi on PMA stimulation, although no differences were observed due to TNF-alpha treatment.

No abstract

No abstract