Thermal ablation using radiofrequency is a new, minimally invasive modality employed as an alternative to surgery in patients with benign thyroid nodules and recurrent thyroid cancers. The Task Force Committee of the Korean Society of Thyroid Radiology (KSThR) developed recommendations for the optimal use of radiofrequency ablation for thyroid tumors in 2012. As new meaningful evidences have accumulated, KSThR decided to revise the guidelines. The revised guideline is based on a comprehensive analysis of the current literature and expert consensus.

Lipopolysaccharide (LPS), the major component of the outer membrane of Gram-negative bacteria, binds Toll-like receptor 4 (TLR4)-MD2 complex and activates innate immune responses. LPS transfer to TLR4-MD2 is catalyzed by both LPS binding protein (LBP) and CD14. To define the sequential molecular interactions underlying this transfer, we reconstituted in vitro the entire LPS transfer process from LPS micelles to TLR4-MD2. Using electron microscopy and single-molecule approaches, we characterized the dynamic intermediate complexes for LPS transfer: LBP-LPS micelles, CD14-LBP-LPS micelle, and CD14-LPS-TLR4-MD2 complex. A single LBP molecule bound longitudinally to LPS micelles catalyzed multi-rounds of LPS transfer to CD14s that rapidly dissociated from LPB-LPS complex upon LPS transfer via electrostatic interactions. Subsequently, the single LPS molecule bound to CD14 was transferred to TLR4-MD2 in a TLR4-dependent manner. The definition of the structural determinants of the LPS transfer cascade to TLR4 may enable the development of targeted therapeutics for intervention in LPS-induced sepsis.

Very limited information is available on the role of phosphatidylinositol 3-phosphate (PI[3]P) in vesicle trafficking in plant cells. To investigate the role of PI(3)P during the vesicle trafficking in plant cells, we exploited the PI(3)P-specific binding property of the endosome binding domain (EBD) (amino acids 1257 to 1411) of human early endosome antigen 1, which is involved in endosome fusion. When expressed transiently in Arabidopsis protoplasts, a green fluorescent protein (GFP):EBD fusion protein exhibited PI(3)P-dependent localization to various compartments-such as the transGolgi network, the prevacuolar compartment, the tonoplasts, and the vesicles in the vacuolar lumen-that varied with time. The internalized GFP:EBD eventually disappeared from the lumen. Deletion experiments revealed that the PI(3)Pdependent localization required the Rab5 binding motif in addition to the zinc finger motif. Overexpression of GFP:EBD inhibited vacuolar trafficking of sporamin but not trafficking of H ؉ -ATPase to the plasma membrane. On the basis of these results, we propose that the trafficking of GFP:EBD reflects that of PI(3)P and that PI(3)P synthesized at the trans -Golgi network is transported to the vacuole through the prevacuolar compartment for degradation in plant cells. INTRODUCTIONEvidence suggests that phosphoinositides play a regulatory role in vesicle trafficking (Camilli et al., 1996; Corvera and Czech, 1998; Gary et al., 1998; Cremona et al., 1999;Leevers et al., 1999;Roth, 1999). Phosphatidylinositol 3-phosphate (PI[3]P) has been implicated in this process (Whitman et al., 1998; Corvera et al., 1999). Direct evidence for the role of PI(3)P in vesicle trafficking was obtained when the yeast VPS34 gene, one of the genes involved in the vesicular protein sorting in yeast, was found to encode a PI3-kinase (Schu et al., 1993). Almost all PI3-kinase activity in yeast can be attributed to Vps34p (Stack et al., 1995;Wurmser and Emr, 1998). However, Vps34p requires a protein kinase, Vps15p, for its activation and membrane association (Stack et al., 1995). Also, a mammalian protein, p110, which is homologous to yeast Vps34p, has PI3-kinase activity and can transduce signals from tyrosine-phosphorylated receptors into a variety of intracellular responses (Volinia et al., 1995). However, this mammalian PI3-kinase, in association with an adapter protein p85, is able to phosphorylate other PI compounds such as PI(4)P and PI(4,5)P 2 at the D3 position of PI (Volinia et al., 1995;Panaretou et al., 1997). It is now clear that PI3-kinases play critical roles in various trafficking events, such as endocytosis of transferrin (Li et al., 1995), endosome fusion (Jones et al., 1998), vacuolar trafficking in yeast (Peterson et al., 1999), vesicle formation at the transGolgi network (TGN) (Hickinson et al., 1997; Jones and Howell, 1997; Jones et al., 1998), vacuole morphogenesis in Schizosaccharomyces pombe (Takegawa et al., 1995), and multivesicular body formation (Fernandez-Borja et al., 1999).PI(3)P is likely to act in ...

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Binding of T cells to antigen-presenting cells leads to the formation of the immunological synapse, translocation of the microtubuleorganizing center (MTOC) to the synapse, and focused secretion of effector molecules. Here, we show that upon activation of Jurkat cells microtubules project from the MTOC to a ring of the scaffolding protein ADAP, localized at the synapse. Loss of ADAP, but not lymphocyte function-associated antigen 1, leads to a severe defect in MTOC polarization at the immunological synapse. The microtubule motor protein cytoplasmic dynein clusters into a ring at the synapse, colocalizing with the ADAP ring. ADAP coprecipitates with dynein from activated Jurkat cells, and loss of ADAP prevents MTOC translocation and the specific recruitment of dynein to the synapse. These results suggest a mechanism that links signaling through the T cell receptor to translocation of the MTOC, in which the minus end-directed motor cytoplasmic dynein, localized at the synapse through an interaction with ADAP, reels in the MTOC, allowing for directed secretion along the polarized microtubule cytoskeleton.I n T cells, engagement of the T cell receptor leads to formation of an immunological synapse, translocation of the microtubule-organizing center (MTOC) to the synapse, and ultimately secretion of effector molecules (1-4). Translocation of the MTOC serves to focus secretion at the synapse and is required for effector function of both helper and cytotoxic T cells (5-8).Previous studies have reported that signaling through ZAP-70, LAT, SLP-76, elevation of intracellular calcium, and Cdc42 are required for MTOC translocation (9 -12). However, the downstream actions that control MTOC translocation remain to be determined. The microtubule motor cytoplasmic dynein is a good candidate to drive the translocation of the MTOC and the resulting polarization of the microtubule cytoskeleton observed in synapse formation (4). Here, we present data with Jurkat cells showing that a dynein complex is recruited to the synapse and that the recruitment of dynein depends on the protein ADAP. ADAP is a SLP-76-associated scaffold protein that links T cell receptor signaling to integrin clustering through its association with SKAP55 and may also be linked to actin dynamics by virtue of its Ena͞vasodilator-stimulated phosphoprotein binding domain (13)(14)(15)(16)(17)(18). Here, we show that ADAP is associated with dynein, and upon T cell activation it forms a ring at the synapse that colocalizes with dynein and microtubules. When ADAP expression is reduced by using antisense morpholino (MO) oligonucleotides, dynein fails to localize to the synapse and MTOC translocation is blocked. Together, these results show a direct connection between T cell signaling, recruitment of dynein to the synapse, and polarization of the microtubule cytoskeleton. ResultsPrevious studies showed that microtubules project toward a ring of lymphocyte function-associated antigen 1 (LFA-1) clustered at the immunological synapse (4). We used LFA-1-deficient Fig. 6, w...