Universal Vector Driven Tester (VDT)

Seung Y. “Daniel” Lee,Byunghwan Chun,Brian Y. Kim,Austin S. Kim 한국통신학회 2006 한국통신학회 학술대회논문집 Vol.2006 No.7

High Dielectric PLZT Thin Films for Embedded Capacitors

김승현,C. Y. Koo,J.-H. Cheon,J. Ha,J.-W. Lee,I.-H. Lee,W. S. Kim,Brian L. Wardle 한국물리학회 2009 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.54 No.2

For realization of next-generation embedded capacitors in high-density printed circuit boards, a high capacitance density and a low loss of capacitor films are needed. To make reliable capaci- tors, we performed a systematic investigation of the dielectric and the ferroelectric properties of (Pb,La)(Zr,Ti)O3 (PLZT) lms with a LaNiO3 (LNO) buffer layer deposited by a chemical solu- tion deposition method for the rhombohedral (La/Zr/Ti = 7/62/38) composition. The films with a LNO buffer layer on Ni-plated Cu foils showed a very dense and uniform microstructure. The PLZT films were found to a reduced hysteretic behavior, unlike general ferroelectric PZT films. The addition of a high concentration of a La dopant, such as 7 mol%, led to almost no or negligible hysteresis and a low coercive voltage, implying that PLZT with a high concentration of La dopant is a good candidate material for embedded capacitor applications. The capacitance values measured in this experiment were approximately 8 times higher than those of undoped PZT on conventional Ni-plated Cu foils. The capacitance density of the films was approximately 2.4 uF/cm2 and the loss tangent was below 1 %. The results show that PLZT films with an appropriate buffer layer, such as LNO, are strong candidates for high-performance embedded capacitors, providing a possibility of realizing next-generation embedded capacitors with ultra-high capacitance in printed circuit boards. For realization of next-generation embedded capacitors in high-density printed circuit boards, a high capacitance density and a low loss of capacitor films are needed. To make reliable capaci- tors, we performed a systematic investigation of the dielectric and the ferroelectric properties of (Pb,La)(Zr,Ti)O3 (PLZT) lms with a LaNiO3 (LNO) buffer layer deposited by a chemical solu- tion deposition method for the rhombohedral (La/Zr/Ti = 7/62/38) composition. The films with a LNO buffer layer on Ni-plated Cu foils showed a very dense and uniform microstructure. The PLZT films were found to a reduced hysteretic behavior, unlike general ferroelectric PZT films. The addition of a high concentration of a La dopant, such as 7 mol%, led to almost no or negligible hysteresis and a low coercive voltage, implying that PLZT with a high concentration of La dopant is a good candidate material for embedded capacitor applications. The capacitance values measured in this experiment were approximately 8 times higher than those of undoped PZT on conventional Ni-plated Cu foils. The capacitance density of the films was approximately 2.4 uF/cm2 and the loss tangent was below 1 %. The results show that PLZT films with an appropriate buffer layer, such as LNO, are strong candidates for high-performance embedded capacitors, providing a possibility of realizing next-generation embedded capacitors with ultra-high capacitance in printed circuit boards.

Dissection of molecular and histological subtypes of papillary thyroid cancer using alternative splicing profiles

Park Jiyeon,Kim Dong-Moung,Lee Jin-Ok,Park Hyeon-Chun,Ryu Brian Y.,Kim Ju Han,Lee Sug Hyung,Chung Yeun-Jun 생화학분자생물학회 2022 Experimental and molecular medicine Vol.54 No.-

Despite growing evidence of the relevance of alternative splicing (AS) to cancer development and progression, the biological implications of AS for tumor behaviors, including papillary thyroid cancer (PTC), remain elusive. With the aim of further understanding the molecular and histological subtypes of PTC, we in this study explored whether AS events might act as new molecular determinants. For this purpose, AS profiles were analyzed in RNA-sequencing data from The Cancer Genome Atlas (TCGA) and from a Korean patient dataset. A total of 23 distinct exon-skipping (ES) events that correlated significantly with PTC oncogenic activity and differentiation scores were identified. The two top-ranked ES events, NUMA1_17515 in exon 18 of NUMA1 and TUBB3_38175 in exon 6 of TUBB3, showed high correlations with oncogenic activities and discriminated histological and molecular subtypes of PTC. Furthermore, two novel intron-retention (IR) events for TUBB3 were uncovered. All ES and IR events for the TUBB3 gene were predicted to induce nonsense-mediated mRNA decay. The relative abundances of intron reads in the PTC dataset from TCGA showed IR levels to differ significantly among PTC subtypes, possibly reflecting their different tumor behaviors. This study provides a landscape of AS changes among PTC subtypes and identified two significant AS events, NUMA1_17515 and TUBB3_38175, as potential AS biomarkers for PTC subclassification and characterization. The AS events identified in this study may be involved in the development of phenotypic differences underlying the functional characteristics and histological differentiation of PTCs.

Downregulation of SIRT1 signaling underlies hepatic autophagy impairment in glycogen storage disease type Ia

Cho, Jun-Ho,Kim, Goo-Young,Pan, Chi-Jiunn,Anduaga, Javier,Choi, Eui-Ju,Mansfield, Brian C.,Chou, Janice Y. Public Library of Science 2017 PLoS genetics Vol.13 No.5

<▼1><P>A deficiency in glucose-6-phosphatase-α (G6Pase-α) in glycogen storage disease type Ia (GSD-Ia) leads to impaired glucose homeostasis and metabolic manifestations including hepatomegaly caused by increased glycogen and neutral fat accumulation. A recent report showed that G6Pase-α deficiency causes impairment in autophagy, a recycling process important for cellular metabolism. However, the molecular mechanism underlying defective autophagy is unclear. Here we show that in mice, liver-specific knockout of G6Pase-α (L-<I>G6pc</I>-/-) leads to downregulation of sirtuin 1 (SIRT1) signaling that activates autophagy via deacetylation of autophagy-related (ATG) proteins and forkhead box O (FoxO) family of transcriptional factors which transactivate autophagy genes. Consistently, defective autophagy in G6Pase-α-deficient liver is characterized by attenuated expressions of autophagy components, increased acetylation of ATG5 and ATG7, decreased conjugation of ATG5 and ATG12, and reduced autophagic flux. We further show that hepatic G6Pase-α deficiency results in activation of carbohydrate response element-binding protein, a lipogenic transcription factor, increased expression of peroxisome proliferator-activated receptor-γ (PPAR-γ), a lipid regulator, and suppressed expression of PPAR-α, a master regulator of fatty acid β-oxidation, all contributing to hepatic steatosis and downregulation of SIRT1 expression. An adenovirus vector-mediated increase in hepatic SIRT1 expression corrects autophagy defects but does not rectify metabolic abnormalities associated with G6Pase-α deficiency. Importantly, a recombinant adeno-associated virus (rAAV) vector-mediated restoration of hepatic G6Pase-α expression corrects metabolic abnormalities, restores SIRT1-FoxO signaling, and normalizes defective autophagy. Taken together, these data show that hepatic G6Pase-α deficiency-mediated down-regulation of SIRT1 signaling underlies defective hepatic autophagy in GSD-Ia.</P></▼1><▼2><P><B>Author summary</B></P><P>GSD-Ia is an autosomal recessive metabolic disorder caused by a deficiency in G6Pase-α, a key enzyme in maintaining blood glucose levels between meals. Despite strong compliance to dietary therapies, GSD-Ia patients continue manifesting metabolic aberrations including excessive accumulation of glycogen and lipid in the liver. Recently, G6Pase-α deficiency has been linked to impairment in autophagy, a recycling process essential for cellular homeostasis. However, the underlying mechanism is unclear. In this study, we show that hepatic G6Pase-α deficiency alters the activity and/or expression of several lipid regulators, leading to hepatic steatosis and reduced expression of SIRT1, an enzyme that regulates the activity of many proteins via deacetylation. The impaired SIRT1 signaling increases the acetylation of ATG proteins critical for autophagic vesicle elongation, and reduces the activity of FoxO factors that can induce autophagy genes. Consistently, the G6Pase-α-deficient liver exhibits autophagy impairment characterized by attenuated expression of many autophagy components, defective autophagic vesicle elongation, impaired autophagosome formation, and reduced autophagy flux. Importantly, SIRT1 overexpression in G6Pase-α-deficient liver corrects autophagy deficiency. Finally, restoration of hepatic G6Pase-α expression corrects metabolic abnormalities, restores SIRT1-FoxO signaling, and normalizes defective autophagy. Collectively, hepatic G6Pase-α deficiency-mediated down-regulation of SIRT1 signaling underlies defective hepatic autophagy in GSD-Ia.</P></▼2>

Shank2E binds NaP(i) cotransporter at the apical membrane of proximal tubule cells.

McWilliams, Ryan R,Breusegem, Sophia Y,Brodsky, Kelley F,Kim, Eunjoon,Levi, Moshe,Doctor, R Brian American Physiological Society 2005 American journal of physiology. Cell physiology Vol.289 No.4

<P>Proteins expressing postsynaptic density (PSD)-95/Drosophila disk large (Dlg)/zonula occludens-1 (ZO-1) (PDZ) domains are commonly involved in moderating receptor, channel, and transporter activities at the plasma membrane in a variety of cell types. At the apical membrane of renal proximal tubules (PT), the type IIa NaP(i) cotransporter (NaP(i)-IIa) binds specific PDZ domain proteins. Shank2E is a spliceoform of a family of PDZ proteins that is concentrated at the apical domain of liver and pancreatic epithelial cell types and is expressed in kidney. In the present study, immunoblotting of enriched plasma membrane fractions and immunohistology found Shank2E concentrated at the brush border membrane of rat PT cells. Confocal localization of Flag-Shank2E and enhanced green fluorescent protein-NaP(i)-IIa in cotransfected OK cells showed these proteins colocalized in the apical microvilli of this PT cell model. Shank2E co-immunoprecipitated with NaP(i)-IIa from rat renal cortex tissue and HA-NaP(i)-IIa coprecipitated with Flag-Shank2E in cotransfected human embryonic kidney HEK cells. Domain analysis showed that the PDZ domain of Shank2E specifically bound NaP(i)-IIa and truncation of the COOH-terminal TRL motif from NaP(i)-IIa abolished this binding, and Far Western blotting showed that the Shank2E- NaP(i)-IIa interaction occurred directly between the two proteins. NaP(i)-IIa activity is regulated by moderating its abundance in the apical membrane. High-P(i) conditions induce NaP(i)-IIa internalization and degradation. In both rat kidney PT cells and OK cells, shifting to high-P(i) conditions induced an acute internal redistribution of Shank2E and, in OK cells, a significant degree of degradation. In sum, Shank2E is concentrated in the apical domain of renal PT cells, specifically binds NaP(i)-IIa via PDZ interactions, and undergoes P(i)-induced internalization.</P>