Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P50583 (asymmetrical)
 12,197 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A novel type of ribonucleoprotein (RNP) complex has been described from the kinetoplast-mitochondria of Leishmania tarentolae. The complex, termed the 45S SSU*, contains the 9S small subunit rRNA but does not contain the 12S large subunit rRNA. This complex is the most stable and abundant mitochondrial RNP complex present in Leishmania. As shown by tandem mass spectrometry, the complex contains at least 39 polypeptides with a combined molecular mass of almost 2.1 MDa. These components include several homologs of small subunit ribosomal proteins (S5, S6, S8, S9, S11, S15, S16, S17, S18, MRPS29); however, most of the polypeptides present are unique. Only a few of them show recognizable motifs, such as protein-protein (coiled-coil, Rhodanese) or protein-RNA (pentatricopeptide repeat) interaction domains. A cryo-electron microscopy examination of the 45S SSU* fraction reveals that 27% of particles represent SSU homodimers arranged in a head-to-tail orientation, while the majority of particles are clearly different and show an asymmetric bilobed morphology. Multiple classes of two-dimensional averages were derived for the asymmetrical particles, probably reflecting random orientations of the particles and difficulties in correlating these views with the known projections of ribosomal complexes. One class of the two-dimensional averages shows a SSU moiety attached to a protein mass or masses in a monosome-like appearance. The combined mass spectrometry and electron microscopy data thus indicate that the majority 45S SSU* particles represents a heterodimeric complex in which the SSU of the Leishmania mitochondrial ribosome is associated with an additional protein mass. The biological role of these particles is not known.
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PMID:Proteomics and electron microscopic characterization of the unusual mitochondrial ribosome-related 45S complex in Leishmania tarentolae. 1729 89

Microwave ablation (MWA) is a minimally invasive thermal therapy modality increasingly employed for the treatment of tumors and benign disease. For successful treatment, complete thermal coverage of the tumor and margin of surrounding healthy tissue must be achieved. Currently available interstitial antennas for MWA have cylindrically symmetric radiation patterns. Thus, when treating targets in proximity to critical structures, caution must be taken to prevent unintended thermal damage. A novel coaxial antenna design for MWA with an asymmetrical cylindrical heating pattern is presented in this paper. This radiation pattern is achieved by employing a hemicylindrical reflector positioned at a critical distance from a conventional coaxial monopole antenna. Finite-element method simulations were employed to optimize the geometric dimensions of the antenna with the objective of minimizing the antenna reflection coefficient at the 2.45-GHz operating frequency, and maximizing volume of the ablation zone. Prototype antennas were fabricated and experimentally evaluated. Simulations indicated an optimal S11 of -32 dB at 2.45 GHz in close agreement with experimental measurements of -29 dB. Ex vivo experiments were performed to validate simulations and observe effects to the antennas' heating pattern with the varying input power and geometry of the reflector. Ablation zones up to 20 mm radially were observed in the forward direction, with minimal heating (less than 4 mm) behind the reflector.
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PMID:A Directional Interstitial Antenna for Microwave Tissue Ablation: Theoretical and Experimental Investigation. 2579 85