• Journal of Adhesion and Interface
• /
• v.8 no.1
• /
• pp.15-27
• /
• 2007

Polyimide (PI) surface modification was carried out by ion-beam treatment and silane-imidazole coupling agent to improve the adhesion between polyimide film and copper. Silane-imidazole coupling agent contains imidazole functional groups for the formation of a complex with copper metal through a coordination bonding and methoxy silane groups for the formation of siloxane polymers. The PI film surface was first treated by argon (Ar)/oxygen ($O_2$) ion-beam, followed by dipping it into a modified silane-imidazole coupling agent solution. The results of X-ray photoelectron spectroscopy (XPS) spectra revealed that the $Ar/O_2$ plasma treatment formed oxygen functional groups such as hydroxyl and carbonyl groups on the polyimide film surface and confirmed that the PI surface was modified by a coupling reaction with imidazole-silane coupling agent. Adhesion between copper and the treated PI film by ion-beam and coupling agent was superior to that with untreated PI film. In addition, adhesion of PI film treated by an $Ar/O_2$ plasma to copper was better than that of PI film treated by a coupling agent. The peeled-off layers from the copper-PI film joint were completely different in chemical composition each other. The layer of PI film side showed similar C1s, N1s, O1s spectra to the original Upilex-S and no Si and Cu atoms appeared. On the other hand the layer of copper side showed different C1s and N1s spectra from the original PI film and many Si and Cu atoms appeared. This indicates that the failure occurs at an interface between the imidazole-silane and PI film layers rather than within the PI layers.

• Molecules and Cells
• /
• v.37 no.7
• /
• pp.547-553
• /
• 2014

Glioblastoma multiforme (GBM) is one of the most common brain malignancies and has a very poor prognosis. Recent evidence suggests that the presence of cancer stem cells (CSC) in GBM and the rare CSC subpopulation that is resistant to chemotherapy may be responsible for the treatment failure and unfavorable prognosis of GBM. A garlic-derived compound, Z-ajoene, has shown a range of biological activities, including anti-proliferative effects on several cancers. Here, we demonstrated for the first time that Z-ajoene specifically inhibits the growth of the GBM CSC population. CSC sphere-forming inhibition was achieved at a concentration that did not exhibit a cytotoxic effect in regular cell culture conditions. The specificity of this inhibitory effect on the CSC population was confirmed by detecting CSC cell surface marker CD133 expression and biochemical marker ALDH activity. In addition, stem cell-related mRNA profiling and real-time PCR revealed the differential expression of CSC-specific genes, including Notch, Wnt, and Hedgehog, upon treatment with Z-ajoene. A proteomic approach, i.e., reverse-phase protein array (RPPA) and Western blot analysis, showed decreased SMAD4, p-AKT, 14.3.3 and FOXO3A expression. The protein interaction map (http://string-db.org/) of the identified molecules suggested that the AKT, ERK/p38 and $TGF{\beta}$ signaling pathways are key mediators of Z-ajoene's action, which affects the transcriptional network that includes FOXO3A. These biological and bioinformatic analyses collectively demonstrate that Z-ajoene is a potential candidate for the treatment of GBM by specifically targeting GBM CSCs. We also show how this systemic approach strengthens the identification of new therapeutic agents that target CSCs.

• Clinical and Experimental Pediatrics
• /
• v.57 no.1
• /
• pp.50-53
• /
• 2014

Hemophagocytic lymphohistiocytosis (HLH) occurs in the primary form (genetic or familial) or secondary form (acquired). The familial form of HLH (FHL) is a potentially fatal autosomal recessive disorder that occurs because of constitutional defects in cell-mediated cytotoxicity. Here, we report a fatal neonatal case of type 2 FHL (FHL2) that involved a novel frameshift mutation. Clinically, the newborn presented with severe sepsis-like features and required mechanical ventilation and continuous venovenous hemodiafiltration. Flow cytometry analysis showed marked HLH and complete absence of intracytoplasmic perforin expression in cytotoxic cells; therefore, we performed molecular genetic analyses for PRF1 mutations, which showed that the patient had a compound heterozygous mutation in PRF1, that is, c.65delC ($p.Pro22Argfs^*2$) and c.1090_1091delCT ($p.Leu364Glufs^*93$). Clinical and genetic assessments for FHL are required for neonates with refractory fever and progressive multiple organ failure, particularly when there is no evidence of microbiological or metabolic cause.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.16 no.6
• /
• pp.155-162
• /
• 2012

When RC (Reinforced Concrete) structures are exposed to sea water, steel corrosion can occur and this leads a degradation of structural performance. Referring the electro-deposition system with sea water from the 1st step research, durability and structural performance are evaluated in coated steel and RC members containing it in the 2nd research. In the durability performance test, Half Cell Potential test is performed and the coated steel is evaluated to have the high resistance to corrosion, which shows only 35% of corrosion velocity in normal (bare) steel. In the structural performance test, tensile strength, adhesive strength, and flexural/shear in RC member are performed. For the electro-deposit coated steel, increasing ratios of 3.2% and 8.8% are evaluated in the test of tensile strength and adhesive strength, respectively. For the structural test in RC member, there is no big difference between RC members with coated and non-coated steel in ultimate load and failure pattern It is evaluated that the chemical compound with $CaCO_3$ and $Mg(OH)_2$ from electro-deposition causes slightly increased structural performance. The electro-deposit coated steel can be more widely applied after performance verification from several tests like fatigue, resistance to impact, and long term-submerging test.

• Journal of The Korean Society of Inherited Metabolic disease
• /
• v.6 no.1
• /
• pp.15-23
• /
• 2006

Purpose: Glycogen storage disease type III (GSD-III), is a rare autosomal recessive disorder of glycogen metabolism. The affected enzyme is amylo-1,6-glucosidase, 4-alpha-glucanotransferase (AGL, glycogen debranching enzyme), which is responsible for the debranching of the glycogen molecule during catabolism. The disease has been demonstrated to show clinical and biochemical heterogeneity, reflecting the genotype-phenotype heterogeneity among different patients. In this study, we analyzed mutations of the AGL gene in three unrelated Korean GSD-III patients and discussed their clinical and laboratory implications. Methods: We studied three GSD-III patients and the clinical features were characterized. Sequence analysis of 35exons and part exon-intron boundaries of the AGLgene in patients were carried out by direct DNA sequencing method using genomic DNA isolated from patients' peripheral leukocytes. Results: The clinical features included hepatomegaly (in all patients), seizures (in patient 2), growth failure (in patients 1), hyperlipidemia (in patients 1 and 3), raised transaminases and creatinine kinase concentrations (in all patients) and mild EKG abnormalities (in patients 2). Liver transplantation was performed in patient 2due to progressive hepatic fibrosis. Administration of raw-corn-starch could maintain normoglycemia and improve the condition. DNA sequence analysis revealed mutations in 5 out of 6 alleles. Patient 1 was a compound heterozygote of c.1282 G>A (p.R428K) and c.1306delA (p.S603PfsX6), patient 2 with c.1510_1511insT (p.Y504LfsX10), and patient 3 with c.3416 T>C (p.L1139P) and c.l735+1 G>T (Y538_R578delfsX4) mutations. Except R428K mutation, 4 other mutations identified in3 patients were novel. Conclusion: GSD-III patients have variable phenotypic characteristics resembling GSD-Ia. The molecular defects in the AGL gene of Korean GSD-III patients were genetically heterogeneous.

• Journal of The Korean Society of Inherited Metabolic disease
• /
• v.12 no.1
• /
• pp.58-63
• /
• 2012

Classical galactosemia (OMIM# 230400) is an autosomal recessive disorder of carbohydrate metabolism, due to a complete loss in galactose-1-phosphate uridyltransferase (GALT; E.C.2.7.7.12) enzyme activity. It caused by mutations in the GALT gene (OMIM$^*$ 606999) that is located at chromosome 9p13. The GALT enzyme deficiency results in a build-up of galactose and galactose-1-phosphate, causing life threatening complications such as feeding problems, failure to thrive, hepatocellular damage, bleeding and sepsis. However, Duarte galactosemia, a variant form of GALT deficiency, has residual GALT enzyme activities in erythrocytes and do not have manifest the symptoms of classical galactosemia. Since the advent of newborn screening (NBS) for galactosemia, we rarely encounter such overwhelmingly ill newborns. The positive NBS with no symptoms indicates the possibility of Duarte galactosemia besides a simple false positive and it has to be differentiated from classical galactosemia which is a medical emergency. In Korea, detection rate of Duarte galactosemia is very low and its genetic information is restrictive, too. We report a case of monozygotic twins with D/G galactosemia compound heterozygote in proven by the mutational analysis of GALT gene, which revealed N314D polymorphism and -119 to -116 delGTCA.

• Proceedings of the Korean Institute of Surface Engineering Conference
• /
• 2018.06a
• /
• pp.102-102
• /
• 2018

Electronic industry had required the finer size and the higher performance of the device. Therefore, 3-D die stacking technology such as TSV (through silicon via) and micro-bump had been used. Moreover, by the development of the 3-D die stacking technology, 3-D structure such as chip to chip (c2c) and chip to wafer (c2w) had become practicable. These technologies led to the appearance of HBM (high bandwidth memory). HBM was type of the memory, which is composed of several stacked layers of the memory chips. Each memory chips were connected by TSV and micro-bump. Thus, HBM had lower RC delay and higher performance of data processing than the conventional memory. Moreover, due to the development of the IT industry such as, AI (artificial intelligence), IOT (internet of things), and VR (virtual reality), the lower pitch size and the higher density were required to micro-electronics. Particularly, to obtain the fine pitch, some of the method such as copper pillar, nickel diffusion barrier, and tin-silver or tin-silver-copper based bump had been utillized. TCB (thermal compression bonding) and reflow process (thermal aging) were conventional method to bond between tin-silver or tin-silver-copper caps in the temperature range of 200 to 300 degrees. However, because of tin overflow which caused by higher operating temperature than melting point of Tin ($232^{\circ}C$), there would be the danger of bump bridge failure in fine-pitch bonding. Furthermore, regulating the phase of IMC (intermetallic compound) which was located between nickel diffusion barrier and bump, had a lot of problems. For example, an excess of kirkendall void which provides site of brittle fracture occurs at IMC layer after reflow process. The essential solution to reduce the difficulty of bump bonding process is copper to copper direct bonding below $300^{\circ}C$. In this study, in order to improve the problem of bump bonding process, copper to copper direct bonding was performed below $300^{\circ}C$. The driving force of bonding was the self-annealing properties of electrodeposited Cu with high defect density. The self-annealing property originated in high defect density and non-equilibrium grain boundaries at the triple junction. The electrodeposited Cu at high current density and low bath temperature was fabricated by electroplating on copper deposited silicon wafer. The copper-copper bonding experiments was conducted using thermal pressing machine. The condition of investigation such as thermal parameter and pressure parameter were varied to acquire proper bonded specimens. The bonded interface was characterized by SEM (scanning electron microscope) and OM (optical microscope). The density of grain boundary and defects were examined by TEM (transmission electron microscopy).

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
• /
• v.11 no.2
• /
• pp.62-70
• /
• 2005

The determination of peripheral nerve conduction velocity is an important part to electrodiagnosis. Its value as neurophysiologic investigative procedure has been known for many years but normal value of median and ulnar motor nerve was poorly reported in Korea. To evaluate of median and ulnar motor nerve terminal latency, amplitude of CMAP(compound muscle action potential), conduction velocity and F-wave latency for obtain clinically useful reference value. 71 normal volunteers(age, 19-65 years; 142 hands) examined who has no history of peripheral neuropathy, diabetic mellitus, chronic renal failure, endocrine disorders, anti-cancer medicine, anti-tubercle medicine, alcoholism, trauma, radiculopathy. Nicolet Viking II was use for detected terminal latency, amplitude of CMAP, conduction velocity and F-wave latency of median and ulnar motor nerve. Data analysis was performed using SPSS. Descriptive analysis was used for obtain mean and standard deviation, independent t-test was used to compare between Rt and Lt side also compare between different in genders. The results are summarized as follows: 1. Median motor nerve terminal latency was right 3.00ms, left 2.99ms and there was no significantly differences between right and left side and genders. 2. Median motor nerve amplitude of CMAP was right 17.26mV, left 1750mV and there was no significantly differences between right and left side and genders. 3. Median motor nerve conduction velocity was right 57.89m/sec, left 58.03m/sec and there was no significantly differences between right and left side and genders. 4. Median motor nerve F-wave latency was right 25.74ms, left 25.59ms and there was significantly differences between genders. 5. Ulnar motor nerve terminal latency was right 2.38ms, left 2.45ms and there was significantly differences between right and left side. 6. Ulnar motor nerve amplitude of CMAP was right 15.99mV, left 16.02mV and there was no significantly differences between right and left side and genders. 7. Ulnar motor nerve conduction velocity was right 60.35m/sec, left 59.73m/sec and there was no significantly differences between right and left side and genders. 8. Ulnar motor nerve F-wave latency was right 25.53ms, left 25.57ms and there was significantly differences between genders.

• The Korean Journal of Physiology and Pharmacology
• /
• v.2 no.3
• /
• pp.323-330
• /
• 1998

Tetrahydroisoquinoline (THI) alkaloids can be considered as cyclized derivatives of simple phenylethylamines. Many of them, especially with 6,7-disubstitution, demonstrate a relatively high affinity for catecholamines. Present study examines the pharmacological action of limited series of THI, using rats' isolated atria and aorta. In addition, a $[^3H]$ prazosin displacement binding study with THI compounds was performed, using rat brain homogenates to investigate whether these probes have ?${\alpha}$-adrenoceptor affinity. We also compared the vascular relaxation potency of these probes with dobutamine. YS 49, YS 51, higenamine and dobutamine, concentration-dependently, relaxed endothelium-denuded rat thoracic aorta precontracted with phenylephrine (PE, 0.1 ${\mu}M$) in which $pEC_{50}$ were $5.56{\pm}0.32$ and $5.55{\pm}0.21$, $5.99{\pm}1.16$ and $5.57{\pm}0.34$, respectively. These probes except higenamine also relaxed KCl (65.4 mM)-contracted aorta. In isolated rat atria, all THIs and dobutamine increased heart rate and contractile force. In the presence of propranolol, the concentration response curves of YS 49 and YS 51 shifted to the right and resulted in $pA_2$ values of $8.07{\pm}0.84$ and $7.93{\pm}0.11$, respectively. The slope of each compound was not deviated from unity, indicating that these chemicals are highly competitive at the cardiac ?${\beta}-adrenoceptors$. YS 49, YS 51, and higenamine showed ?${\alpha)-adrenoceptor$ affinity in rat brain, in which the dissociation constant $(K_i)$ was 2.75, 2.81, and 1.02 ${\mu}M$, respectively. It is concluded, therefore, that THI alkaloids have weak affinity to ${\alpha)_1-adrenoceptor$ in rat aorta and brain, respectively, while these probes show relatively high affinity for cardiac ${\beta}-adrenoceptors$. Thus, these chemicals may be useful in the treatment of congestive heart failure.

• Journal of The Korean Society of Inherited Metabolic disease
• /
• v.21 no.1
• /
• pp.22-27
• /
• 2021

Propionic acidemia (PA) is an inherited autosomal recessive disorder, due to the deficiency of propionyl-CoA carboxylase (PCC). PCC is the enzyme which catalyzes the conversion of propionyl-CoA to D-methylmalonyl-CoA, and it is critical for the metabolism of amino acids, odd-chain fatty acids, and side chains of cholesterol. The clinical manifestations present mostly at the neonatal period with life-threatening metabolic acidosis and hyperammonemia. Here, we described a case of a 16-year-old Korean boy with late-onset PA who presented with embolic cerebral infarction due to dilated cardiomyopathy (DCMP) with left ventricular noncompaction. And he has family history of sudden cardiac death, so we performed metabolic screening and genetic tests. Elevated levels of 3-hydroxypropionic acid, methylcitric acid and propionylglycerine were detected in urine. Plasma acylcarnitine profile showed elevated propionylcarnitine (C3). Diagnosis of PA was confirmed by genetic analysis, which revealed compound heterozygous mutations, c.[1151T>G] (p.[Phe384Cys]) and c.[1228C>T] (p.[Arg410Trp]) in PCCB gene. His heart function is in improving state and the results of biochemical analysis are stable with heart failure medication and metabolic managements. We present a case of patient without episodes of metabolic decompensation who manifests DCMP as the first symptom of PA.