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2.
J Agric Saf Health ; 13(1): 33-43, 2007 Jan.
Article En | MEDLINE | ID: mdl-17370912

This article discusses the pollution caused by chrome composite leather-clad (CCLC) rollers commonly used in cotton roller ginning mills and suggests an alternative roller material. CCLC rollers contain about 18,000 to 36,000 mg/kg (ppm) total chromium in trivalent and hexavalent forms, which are toxic to human health and carcinogenic. When seed-cotton is processed in double roller (DR) ginning machines, the lint is contaminated with chromium, and chromium particles are carried into the spun yarns and cotton by-products. Specifically, due to persistent rubbing of the leather-clad roller over the stationary knife during the ginning process, the lint is contaminated with about 140 to 1990 ppm of chromium, and the spun yarns and cotton by-products contain about 100 to 200 ppm, far in excess of the standard limit of 0.1 ppm. Gin and mill workers are directly exposed to this carcinogenic substance. To offset this problem, pollution-free rubberized cotton fabric (RCF) rollers have been fabricated and tested in roller gins. The RCF roller covering is made of multiple layers of fabric bonded together using a white rubber compound, which has a surface finish conducive to high ginning efficiency. This eliminates chromium contamination and pollution during the ginning process. On the basis of the design and development of various test rollers and subsequent evaluation studies, the performance of pollution-free RCF rollers has been demonstrated with reference to their commercial benefit and eco-friendliness in cotton ginning mills.


Agriculture/instrumentation , Chromium/toxicity , Environmental Pollution/prevention & control , Gossypium/chemistry , Occupational Diseases/chemically induced , Trace Elements/toxicity , Carcinogens/toxicity , Cotton Fiber , Humans , Rubber , Textiles
3.
J Biol Chem ; 273(33): 21359-67, 1998 Aug 14.
Article En | MEDLINE | ID: mdl-9694897

Based on UV cross-linking experiments, it has been reported that the C protein tetramer of 40 S heterogeneous nuclear ribonucleoprotein complexes specifically interacts with stem-loop I of U2 small nuclear RNA (snRNA) (Temsamani, J., and Pederson, T. (1996) J. Biol. Chem. 271, 24922-24926), that C protein disrupts U4:U6 snRNA complexes (Forne, T., Rossi, F., Labourier, E., Antoine, E., Cathala, G., Brunel, C., and Tazi, J. (1995) J. Biol. Chem. 270, 16476-16481), that U6 snRNA may modulate C protein phosphorylation (Mayrand, S. H., Fung, P. A., and Pederson, T. (1996) Mol. Cell. Biol. 16, 1241-1246), and that hyperphosphorylated C protein lacks pre-mRNA binding activity. These findings suggest that snRNA-C protein interactions may function to recruit snRNA to, or displace C protein from, splice junctions. In this study, both equilibrium and non-equilibrium RNA binding assays reveal that purified native C protein binds U1, U2, and U6 snRNA with significant affinity ( approximately 7.5-50 nM) although nonspecifically. Competition binding assays reveal that U2 snRNA (the highest affinity snRNA substrate) is ineffective in C protein displacement from branch-point/splice junctions or as a competitor of C protein's self-cooperative RNA binding mode. Additionally, C protein binds snRNA through its high affinity bZLM and mutations in the RNA recognition motif at suggested RNA binding sites primarily affect protein oligomerization.


RNA, Small Nuclear/metabolism , RNA-Binding Proteins/metabolism , Ribonucleoproteins/metabolism , HeLa Cells , Heterogeneous-Nuclear Ribonucleoproteins , Humans , Phosphorylation , Protein Binding , RNA, Small Nuclear/chemistry , Ribonucleoproteins/chemistry , Uridine/metabolism
9.
Neurol India ; 23(2): 105-8, 1975 Jun.
Article En | MEDLINE | ID: mdl-1214947
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