Objective: The fibrogenicity of fur dust was studied in rat lung tissues. Methods: Intratracheal instillation of fur dust, morphologic examination of lungs and analysis of collagen content were performed in Wistar rats. Results: Morphologic examination revealed that the earliest changes consisted of alveolar edema, increased numbers of intraalveolar macrophages, and marked thickening of interalveolar septa with mixed cellular infiltrate. After sixth months, there was moderate thickening of the alveolar walls and the peribronchioli. After 12 months, interstitial positive fibrosis of the alveolar wall and the peribronchioli were weakly seen. In the carding dust group (silica content 17.6%), interstitial nodules were observed composed of fibroblasts, reticular fibers, and collagen fibers. Electron microscopic examination also showed that alveolar walls became thickened and collagen fiber bundles were seen around bronchioles and small vessels in the carding groups after 12 months. At all stages of analysis, the collagen content in lungs of the fur dust groups was significantly higher than that of the control group. Conclusions: Our study suggested that fur dust might induce weak interstitial fibrosis in the lung.
Dust ; Collagen ; interstitial ; month ; seconds

OBJECTIVEThe fibrogenicity of fur dust was studied in rat lung tissues.

METHODSIntratracheal instillation of fur dust, morphologic examination of lungs and analysis of collagen content were performed in Wistar rats.

RESULTSMorphologic examination revealed that the earliest changes consisted of alveolar edema, increased numbers of intraalveolar macrophages, and marked thickening of interalveolar septa with mixed cellular infiltrate. After sixth months, there was moderate thickening of the alveolar walls and the peribronchioli. After 12 months, interstitial positive fibrosis of the alveolar wall and the peribronchioli were weakly seen. In the carding dust group (silica content 17.6%), interstitial nodules were observed composed of fibroblasts, reticular fibers, and collagen fibers. Electron microscopic examination also showed that alveolar walls became thickened and collagen fiber bundles were seen around bronchioles and small vessels in the carding groups after 12 months. At all stages of analysis, the collagen content in lungs of the fur dust groups was significantly higher than that of the control group.

CONCLUSIONSOur study suggested that fur dust might induce weak interstitial fibrosis in the lung.

Gsalpha gene mutation has been discovered in some human tumors. In our previous studies, three novel deletants of Gsalpha gene, Gsalpha L-1(500 bp), Gsalpha L-2(300 bp), and Gsalpha L-3(200 bp), and wild type Gsalpha-4(1 200 bp) were found in human leukemia cell lines and detected in leukemic cells from patients with acute leukemia. To investigate the construction, function and biological significance of the deletants, the plasmids of Gsalpha L-1, Gsalpha L-2 and wild Gsalpha-4 were transformed into E. coli DH5, amplified by PCR, and cloned in expression vector pET22b(+), and then transformed into E. coli, respectively. As a result, higher levels of expression of three recombinants were obtained in form of inclusion bodies. The results suggested that these Gsalpha isoforms have an open reading frame of gene and can be expressed in vitro. The data lay a foundation to study the relation of Gsalpha gene to leukemogenesis.