Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.2.1.31 (beta-glucuronidase)
 7,680 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The dynamics of the biological response of pulmonary tissue to silica dust (silica earth from Piotrowice, Poland, recommended as a domestic reference fibrogenic standard) was studied in rats after single-shot intratracheal instillation of a suspension of 20 mg of the dust for one, three, and seven months. Silica dust provoked pronounced pulmonary fibrosis as inferred from increased collagen content together with pathomorphological alteration (silicotic nodules). The lung burden of silica dust affected the lysosomal subfraction as manifested by an increase in its protein content with concomitant stimulation (release and presumably induction) of beta-glucuronidase and cathepsin D and a transient (up to three months) stimulation of lipid peroxidation. Stimulation of activity of lysosomal enzymes and lipid peroxidation mediated by silica dust may reflect destructive metabolic processes resulting in the development of pulmonary fibrosis as the sign of a pathological repair mechanism. The extent of the effects brought about by silica earth testify that it may be recommended as a reference standard for evaluating the potential health hazard from industrial exposure to dusts containing SiO2.
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PMID:Silica earth provoked lung fibrosis with stimulation of lysosomal enzymes and lipid peroxidation in rats. 283 69

Chemical alteration of the glucocorticoid, methylprednisolone, has led to the introduction of a new class of compounds called the 21-aminosteroids (21-ASs). The purpose of this study was to investigate the effect of the 21-AS, U74389G, on silica-induced acute lung injury. Male Fischer 344 rats were treated intraperitoneally with saline or U74389G in a total dose of 15 mg/kg divided into three injections of 5 mg/kg separated by 4 h. Following the first treatment, animals from the two groups were intratracheally instilled with silica (10 mg/100 g body wt in 0.5 ml of saline) or saline vehicle (0.5 ml). Twenty-four hours after the instillations, bronchoalveolar lavage (BAL) was performed. In the animals not receiving U74389G, marked increases in total protein, beta-glucuronidase, and lactate dehydrogenase (LDH) activities and number of neutrophils (PMNs) were demonstrated in the BAL fluid of the silica-treated animals compared to their controls. Silica also caused dramatic increases in the luminol-dependent chemiluminescence (CL) of lung tissue and BAL cells. The CL reaction was decreased by superoxide dismutase (SOD) and N-nitro-L-arginine methyl ester hydrochloride (L-NAME), a nitric oxide (NO) synthase inhibitor. In animals treated with U74389G, there was attenuation of the silica-induced increases in biochemical, cellular, and chemiluminescent indices of damage. This study demonstrates that U74389G significantly reduces acute lung injury caused by the intratracheal instillation of silica, and this drug may be of potential value for treatment of lung diseases in which damage caused by reactive oxygen species has been implicated.
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PMID:Attenuation of acute inflammatory effects of silica in rat lung by 21-aminosteroid, U74389G. 770 90

Three types of callus tissues established from anther culture of eleven doubled haploid (DH) lines of wheat (Triticum aestivum L.) were evaluated for their ability in enhancing friable embryogenic (Type II) culture differentiation and genetic transformation. Differences between types of callus inocula were highly significant (P < 0.001), suggesting that the quality of the initial callus explant is of profound importance in encouraging the proliferation of Type II cultures. Other factors found to be crucial included weekly subculture of friable embryogenic callus tissues on a maintenance medium containing 30 microM dicamba and a predominance of amino-acid nitrogen supplement. Transfer and integration of the beta-glucuronidase gene was also affected by the type of inoculum when suitable embryogenic cell cultures were transformed using silicon carbide whiskers and high velocity microprojectiles. Expression of the hygromycin phosphotransferase selectable marker gene sequence was confirmed in all the stably transformed cell lines maintained on selection media containing lethal levels of hygromycin. Comparatively, there were differences in the frequency of regenerable, transgenic clonal segments between whisker-treated and microprojectile bombarded tissues mainly as a result of the fact that cultures vortexed with whiskers were more capable of post-treatment cell proliferation and embryo differentiation than those bombarded with cDNA-coated microprojectiles. Conditions for obtaining these results are outlined and discussed in relation to the suitability of the two transformation strategies for producing transgenic cell aggregates of wheat.
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PMID:Cytodifferentiation and transformation of embryogenic callus lines derived from anther culture of wheat. 1093 25