Biomedical subjects

J E London

Publications and source records attributed to J E London.

At least 19 recordsLinked to original sources

PubMed1993

Lung hyperpermeability and changes in biochemical constituents in bronchoalveolar lavage fluids following X irradiation of the thorax.

Groups of rats were administered different doses of X rays (7.5 and 15 Gy), and the effect on the permeability of their lungs was evaluated during a time frame within which radiation pneumonitis develops. Sham-exposed animals served as controls. End points surveyed included lung weight and increases in the total protein in the lavage fluid. To obtain more detailed information about hyperpermeability and to examine some specific protein changes that occur in the lung's fluid in response to X irradiation, the lavage fluids were subjected to a reverse-phase HPLC technique that resolves 11 fractions quantitatively, including transferrin, albumin, and immunoglobulins derived from blood, as well as eight other protein and nonprotein constituents that appear to be derived from the lung (fractions 1, 2, 6-11). The earliest change following the 7.5-Gy dose was a decrease in fraction 6 at 1 week after exposure. As of Week 5, the lung weight and total protein in the lavage fluid were all normal, while the HPLC analyses revealed significant and equivalent increases in the amount of transferrin, albumin, and immunoglobulins in the lavage fluid; fraction 6 was no longer diminished. At 9 and 13 weeks, hyperpermeability could no longer be detected, while fraction 6 was again decreased at week 13. Fraction 6 was also decreased 1 week after the 15-Gy dose. At 5 weeks, when the weight of the lungs and the total protein in the lavage fluid were elevated, lavage fractions 1, 2, 10, and 11 were all increased, and transferrin, albumin, and immunoglobulins were increased approximately 1500, 1000, and 500%, respectively, and fractions 6 and 9 were decreased. By Week 7, the weight of the lungs returned to control limits, while total protein in the lavage fluid remained elevated. The hyperpermeability was characterized by increases in transferrin and albumin in the lavage fluid, but not immunoglobulins. Fractions 1, 2, 10, and 11 returned to within normal limits, whereas fraction 9 decreased further. Increases in transferrin and albumin were components of a persisting hyperpermeability observed at the last 9-week time point. All other fractions were normal, with the exception of fraction 6, which remained decreased.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗

PubMed1991

High-performance capillary electrophoresis of proteins from the fluid lining of the lungs of rats exposed to perfluoroisobutylene.

Measurements of the biochemical constituents in the fluid lining of the lung can be used for diagnosing and assessing lung disorders. To facilitate such measurements, a high-performance capillary electrophoresis (HPCE) method has been developed by which the proteins in lung fluid can be analyzed. The lung fluid was obtained by a bronchoalveolar lavage procedure using 48 ml of physiological saline to wash out the lung fluid of rats. The proteins were precipitated from the fluid with 10 volumes of acetone and concentrated by dissolution in 2 ml of water containing 0.2% of trifluoroacetic acid. Aliquots of these samples (5 microliters) were then injected into a Bio-Rad HPE-100 capillary electrophoresis instrument fitted with a 50 cm x 50 microns I.D. coated capillary filled with 0.1 M phosphate buffer (pH 2.5). With phosphate buffer in the outlet electrode chamber (cathode) and water in the inlet electrode chamber (anode), the proteins were loaded into the capillary electrophoretically for 10 s at 10 kV constant voltage. The inlet electrode chamber was then filled with phosphate buffer and HPCE was performed at 8 kV constant voltage. Six major protein fractions were resolved in 35 min, and were detected by UV absorption at 200 nm. The procedure was used to compare the lung fluid proteins of normal untreated rats with those of rats exposed by inhalation to perfluoroisobutylene (PFIB) at a concentration of 100 mg/m3. It was found that PFIB induced pulmonary edema involving a translocation of blood compartment proteins into the lung's alveolar compartment. Comparison of the HPCE fractions with similar fractions obtained by high-performance liquid chromatography confirmed albumin, transferrin and IgG as three major proteins translocated into the alveolar space after PFIB exposure.

Albumins↗

PubMed1991

High-performance capillary electrophoresis of histones.

A high-performance capillary electrophoresis (HPCE) system was developed for the fractionation of histones. This system involves electroinjection of the sample and electrophoresis in 0.1 M phosphate buffer (pH 2.5) in a 35 cm x 50 micron I.D. coated capillary. Electrophoresis was accomplished in 9 min, separating a whole histone preparation into its components in the following order of decreasing mobility: (MHP) H3, H1 (major variant), H1 (minor variant), (LHP) H3, (MHP) H2A (major variant), (LHP) H2A, H4, H2B and (MHP) H2A (minor variant), where MHP is the more hydrophobic component and LHP is the less hydrophobic component. This order of separation is very different from that found in acid-urea polyacrylamide gel electrophoresis and in reversed-phase high-performance liquid chromatography and, thus, brings the histone biochemist a new dimension for the qualitative analysis of histone samples.

Animals↗

PubMed1988

An HPLC procedure for the analysis of proteins in lung lavage fluid.

A high-performance liquid chromatography method has been developed for fractionating the protein components of the lung's extracellular lining fluid, as sampled by bronchoalveolar lavage. With this method, 10 ml (or less) of rat bronchoalveolar lavage fluid (BALF) in phosphate-buffered saline can be quantitatively analyzed rapidly and reproducibly. This volume (25% of the lavage fluid volume from one rat using a standardized lavage technique) is made 0.2% with respect to trifluoroacetic acid (TFA) and pumped through a microBondapak C18 Radial-PAK HPLC column equilibrated with H2O/0.2% TFA. Six fractions are then eluted with a series of acetonitrile gradients and isocratic steps that progress from H2O/0.2% TFA to 65% CH3 CN/0.2% TFA. Following this, 5 additional fractions are eluted with methanol. All 11 fractions are detected by monitoring the column effluents at 206 nm and can be recovered by lyophilization since all the components of the HPLC solvent system are volatile. Nine of the 11 fractions were found to contain protein. Three of the fractions contained proteins common to the blood compartment. The largest fraction of these was albumin, followed by a fraction containing immunoglobulins. Six other protein fractions appeared to be derived from the cells of the lung inasmuch as they were not detected in plasma. Two fractions contained no protein or phospholipids, whereas the most hydrophobic protein fraction did contain phospholipids. A major phospholipid fraction containing no protein eluted early in the chromatogram and was not detectable at 206 nm. This HPLC procedure offers significant utility for identifying and quantifying alterations in several BALF constituents during the development and progression of environmentally induced lung diseases as well as other pulmonary disorders.

Animals↗

PubMed1981

Pulmonary tumours in Syrian hamsters following inhalation of 239PuO2.

Syrian hamsters were exposed to various levels of aerosolized 239PuO2 particles to attain a range of initial lung burdens (medians ranged from 40 to 144 nCi). They were allowed to live without sacrifice and had gross and microscopic tissue examinations at death. Over a range of median lung doses from 4-12 000 rad there was an average 2 per cent incidence of malignant tumours (adenocarcinomas) and 9 per cent incidence of total tumours (primarily adenomas). Some of these results are consistent with those from other laboratories using plutonium oxide aerosols but they represent considerably lower lung tumour incidences than previously observed in this laboratory using aerosols of 238PuO2-ZrO2 particles.

Animals↗

PubMed1980