Rat alveolar macrophages are susceptible to activation by free and liposome-encapsulated lymphokines

Alveolar macrophages (AM) obtained from F344 rats were rendered tumoricidal by incubation in vitro with cellfree culture supernatant fluids rich in macrophage-activating factor (MAF) activity harvested from mitogen-stimulated F344 rat lymphocytes. AM activated by this procedure destroyed syngeneic, allogeneic, and xenogeneic tumor cells but were not cytotoxic for nonneoplastic cells. MAF was encapsulated in multilamellar lipid vesicles (liposomes) and its ability to render AM tumoricidal was compared with that of free (unencapsulated) MAF. Liposome-encapsulated MAF rendered AM cytotoxic at concentrations up to 16,000 times lower than free MAF. These data demonstrate that AM can respond in vitro to lymphokines and that MAF encapsulated within liposomes is far more efficient in rendering AM tumoridical than free MAF.

Rat alveolar macrophages are susceptible to activation by free and liposome-encapsulated lymphokines

Alveolar macrophages (AM) obtained from F344 rats were rendered tumoricidal by incubation in vitro with cellfree culture supernatant fluids rich in macrophage-activating factor (MAF) activity harvested from mitogen-stimulated F344 rat lymphocytes. AM activated by this procedure destroyed syngeneic, allogeneic, and xenogeneic tumor cells but were not cytotoxic for nonneoplastic cells. MAF was encapsulated in multilamellar lipid vesicles (liposomes) and its ability to render AM tumoricidal was compared with that of free (unencapsulated) MAF. Liposome-encapsulated MAF rendered AM cytotoxic at concentrations up to 16,000 times lower than free MAF. These data demonstrate that AM can respond in vitro to lymphokines and that MAF encapsulated within liposomes is far more efficient in rendering AM tumoridical than free MAF.

Normal anatomy of thymus and anterior mediastinum by pneumomediastinography

Normal radiographic appearances of the thymus and anterior and superior mediastinum based on 34 pneumomediastinograms performed on myasthenia gravis patients are discussed. Knowledge of (1) end-on shadow of major vessels in the mediastinum, (2) topographic relation between major vessels and bilateral lobes of the thymus, (3) variable shape, size, and uneven outline of the normal thymus, and (4) irregularly distributed mediastinal fat, helps make more precise radiographic interpretation in this region.

Evaluation of the progress and prognosis of adult respiratory distress syndrome. Simple respiratory physiologic measurement

In our study of 14 patients with adult respiratory distress syndrome (ARDS), we measured A-aDO2, VD/VT, arterial-to-end tidal PCO2 ), effective dynamic compliance, and pulmonary vascular resistance on a daily basis. At the onset of ARDS, all patients showed bilateral interstitial edema on the chest X-ray films, P(A-a)O2 of more than 500 mm Hg, marked decrease in effective dynamic compliance, a moderate increase in VD/VT, and a normal value of a-etPCO2. Pulmonary vascular resistance was low. After seven days, all of those who subsequently died and developed persistent elevation of P(A-a)O2, significant increase in VD/VT, a-etPCO2 and pulmonary vascular resistance, and significant decrease in effective dynamic compliance compared to the values at the onset of ARDS. Those abnormalities diverged significantly from the findings in those who survived. By evaluating sequential changes of those parameters, we might be able to predict an accurate prognosis of ARDS.