High-resolution computed tomography classification of lung fibrosis for patients with asbestos-related disease.

OBJECTIVES: This study tested a new high-resolution computed tomography (HRCT) scoring method for asbestos-induced parenchymal changes in the lung. METHODS: HRCT scans of 602 asbestos-exposed workers and 49 referents were reviewed by 3 radiologists. Structured forms were filled out for a semiquantitative HRCT fibrosis score based on several specified parenchymal abnormalities scored separately. Observer agreement was studied with the use of the quadratic-weighted kappa (kappaqw). The HRCT fibrosis score (from 0 to V with definitions and index images given retrospectively) was compared with the radiographic classification of the International Labour Office (ILO) for the same patients. Receiver-operating characteristic (ROC) curves were computed to compare the tests for diagnosing asbestosis. RESULTS: Good inter- and intraobserver agreements were achieved (kappaqw = 0.64 and 0.72, respectively) as regards the HRCT fibrosis score. All the specified computed tomography findings explained 86% of the variance in the HRCT fibrosis score. Age and occupational group were significant predictors of fibrosis. The area under the ROC curve was significantly greater for the HRCT fibrosis score (0.89) than for the ILO radiographic classification (0.76). The sensitivity (70%) and specificity (91%) of the HRCT fibrosis score (classes I/II-V representing asbestosis) were better than those of the classification published by the International Labour Office (51% and 89%, respectively, score > or = 1/0 representing asbestosis). CONCLUSIONS: The examined HRCT scoring method proved to be a simple, reliable, and reproducible method for classifying lung fibrosis and diagnosing asbestosis also in large populations with occupational disease, and it would be possible to use it as a part of an international classification.

Quantitative determination of aqueous flare and cells in healthy eyes.

We studied 263 eyes of 141 normal subjects, 33 men and 108 women, including 129 Finns and 12 Ibero-Americans, with the age ranging between 12 and 89 (mean 43.0 +/- 20.4) years using the Kowa FC-1000 laser flare cell meter. The mean photon count/ms was 4.5, it was 3.1 in the age groups of 10-19 years and 11.5 in the age group of 80 years or over; the increase with age was statistically significant (p = 0.0001). There were no significant differences in the photon count/ms between right and left eyes (p = 0.75), between sexes (p = 0.61), or between Ibero-Americans and age-matched Finns (p = 0.62). The mean cell count was 1.1 and there were no significant changes between the right and left eyes (p = 0.56) or between different age (p = 0.38), sex (p = 0.32) and race (p = 0.64) groups. There were no significant differences in the mean photon count/ms (p = 0.97) and cell counts (p = 0.35) between the first and second measurements 5 min later. There was no subject-within variability after 24 h and 7 days in the flare (p = 0.95) and cell counts (p = 0.89).

Measurement of protein concentration of aqueous humour in vivo: correlation between laser flare measurements and chemical protein determination.

We studied the correlation between laser flare cell meter photon count/ms and actual protein concentration both in vitro and in vivo. Laser flare cell meter measurement of human albumin concentrations of 0 to 10 g/l showed photon counts/ms from 0.3 +/- 0.3 to 78.9 +/- 3.9. There was a statistically highly significant linear correlation between photon count/ms and human albumin concentration (r = 0.98, p = 0.0001). Laser flare cell meter measurements were done on 39 cataract patients with the mean age of 77.9 +/- 6.7 years. Aqueous humour obtained by peroperative paracentesis was analysed for total protein. The mean photon count/ms before pupillary dilatation was 11.93 +/- 6.03. There was a significant linear correlation (r = 0.4, p = 0.019) between the photon count/ms after pupillary dilatation (mean 14.73 +/- 12.9, range 2.6-62.4) and anterior chamber protein concentration (mean 0.62 +/- 0.27, range 0.23-1.3 g/l) with the linear regression formula being y = 0.231 x -1.105 where y = log protein concentration (g/l) and x = log of photon count/ms. Laser flare cell meter photon counts/ms may be converted into an equivalent anterior chamber total protein concentration using this formula.

Molecular cloning of human lysyl oxidase and assignment of the gene to chromosome 5q23.3-31.2.

Lysyl oxidase (EC 1.4.3.13) initiates the crosslinking of collagens and elastin by catalyzing oxidative deamination of the epsilon-amino group in certain lysine and hydroxylysine residues. We report here on the isolation and characterization of cDNA clones for the enzyme from human placenta and rat aorta lambda gt11 cDNA libraries. A cDNA clone for human lysyl oxidase covers all the coding sequences, 230 nucleotides of the 5' and 299 nucleotides, of the 3' untranslated sequences, including a poly(A) tail of 23 nucleotides. This cDNA encodes a polypeptide of 417 amino acid residues, including a signal peptide of 21 amino acids. Sequencing of two rat lysyl oxidase cDNA clones indicated six differences between the present and the previously published sequence for the rat enzyme [Trackman et al. (1990) Biochemistry 29: 4863-4870], resulting in frameshifts in the translated sequence. The human lysyl oxidase sequence was found to be 78% identical to the revised rat sequence at the nucleotide level and 84% identical at the amino acid level, with the degree of identity unevenly distributed between various regions of the coded polypeptide. Northern blot analysis of human skin fibroblasts RNA indicated that the human lysyl oxidase cDNA hybridizes to at least four mRNA species; their sizes are about 5.5, 4.3, 2.4, and 2.0 kb. Analysis of a panel of 25 human x hamster cell hybrids by Southern blotting mapped the human lysyl oxidase gene to chromosome 5, and in situ hybridization mapped it to 5q23.3-31.2.(ABSTRACT TRUNCATED AT 250 WORDS)