Nuclear particles extraction

In summary, we conclude that at the moment the best way for isolation of the nuclear particles containing D-RNA is a simple extraction with a salt solution of physiologic concentration in the presence or absence of the RNase inhibitor. 

Fig. 3. Resedimentation of particies obtained from different zones of a sucrose gradient in preformed CsCI density gradient. Conditions rotor SW-39 35,000 rpm, 18 hours at 4°C. A.) 30S B.) 606 C.) 100S nuclear particles obtained in the presence of RNase inhibitor D.) 30S particles obtained from the extract in the absence of RNase inhibitor (From Samarina et al. 1968a. J. Molec. Biol., 33 251-263 1967c./Wo/ec. Biol. (U.S.S.R.),...

It is important to note that the proteins of SOS particles differ in their composition from histones, soluble 4S proteins of nuclear extracts, and the proteins of ribosomes. In particular, they are less basic than proteins of ribosomes (Molnar et al., 1968 Samarina et al., 1968a). This further indicates the specific nature and homogeneity of the nuclear particles containing D-RNA. 

Control experiments indicate that such a distribution is not the result of an interaction between the material of the inhibitor and the nuclear particles. If the extract isolated in the usual way is afterward mixed with the inhibitor, only the 308 peak and no heavy particles may be found. And further, if the particles are isolated in the presence of labeled inhibitor, the heavy particles obtained do not contain any label. 

As mentioned, protactinium is one of the rarest elements in existence. Although protactinium was isolated, studied, and identified in 1934, little is known about its chemical and physical properties since only a small amount of the metal was produced. Its major source is the fission by-product of uranium found in the ore pitchblende, and only about 350 milligrams can be extracted from each ton of high-grade uranium ore. Protactinium can also be produced by the submission of samples of throrium-230 (g Th) to radiation in nuclear reactors or particle accelerators, where one proton and one or more neutrons are added to each thorium atom, thus changing element 90 to element 91. 

Tc-99, which has a half life of 2.12 x 10 years, can be recovered from nuclear fission waste in kilogram quantities. Solvent extraction, ion exchange, and volatilization processes are employed to separate it from the numerous other fission products. Because of its long half life and its emission of a soft (low energy) beta particle, it can be safely handled in milligram quantities. Almost all chemical studies of the element have been carried out with this isotope. 

Shaibu, B.S. Reddy, M.L.P. Prabhu, D.R. Kanekar, A.S. Manchanda, V.K. N, N -dimethyl-N, N -dibutyl tetradecyl malonamide impregnated magnetic particles for the extraction and separation of radionuclides from nuclear waste streams, Radiochim. Acta 94 (2006) 267-273. 

Shaibu, B. S., Reddy, M. L. P., Bhattacharyya, A., and Manchanda, V. K., Evaluation of Cyanex 923-coated magnetic particles for the extraction and separation of lanthanides and actinides from nuclear waste streams, J. Magn. Magn. Mater., 301, 312-318, 2006. 

The linear CO stretching frequency for the carbonylated platinum colloid while lower than that found for surface bound CO, is in the range reported for the platinum carbonyl clusters [Pt 3 (CO) 6 ] n / sind we find that the carbonylated colloid is easily transformed into the molecular cluster [Pt 12 (CO) 24 ] (10) reaction with water. The cluster was isolated in 50 yield based on platinum content of the precipitate by extraction with tetraethylammonium bromide in methanol from the aluminum hydroxide precipitated when water is added to the aluminoxane solution. The isolation of the platinum carbonyl cluster reveals nothing about the size or structure of the colloidal platinum particles, but merely emphasizes the high reactivity of metals in this highly dispersed state. The cluster isolated is presumably more a reflection of the stability of the [Pt3(CO)6]n family of clusters than a clue to the nuclearity of the colloidal metal particles - in a similar series of experiments with colloidal cobalt with a mean particle size of 20A carbonylation results in the direct formation of Co2(CO)8. 

Extraction processes (TRUEX, PUREX, Talspeak, DIAMEX, PARC, etc.) generally involve complexation of transplutonium elements by alkyl phosphines, phosphine oxides, phosphoric acids, carbamoyl phosphonates, diamides, and thiophosphinates in aqueous/organic extractions, within derivatized solid supports, or on coated particles. There are excellent reviews of the processes and significant complexes by Mathur et al. and selected chapters in The Chemistry of the Actinide and Transactinide Elements to be published in 2003. " Work on the separation for nuclear waste management in the United States, France, and Russia have been reviewed. " ... 

Proteasome research began in the late 1960s [19] when Harris discovered a barrel-shaped particle in erythrocyte extracts. From then on knowledge about the proteasome and the regulating factors of this protease has been added to step by step. Today it is generally accepted that the ubiquitin-proteasome system is responsible for the turnover of the bulk of intracellular cytosolic and nuclear proteins [20]. It is known that this protease is located in the cytosol, the nucleus, and that it is attached to the ER and other cell membranes. 

Inomata, Y., Kawaguchi, H., Hiramoto, M., Wada, T., Handa, H. (1992). Direct purification of multiple ATF/E4TF3 polypeptides from HeLa cell crude nuclear extracts using DNA-carrying affinity latex particles. Anal. Biochem., 206, 109-114. 

---