Impaired Osteogenesis of Disease-Specific Induced Pluripotent Stem Cells Derived from a CFC Syndrome Patient.

Cardiofaciocutaneous (CFC) syndrome is a rare genetic disorder caused by mutations in the extracellular signal-regulated kinase (ERK) signaling. However, little is known about how aberrant ERK signaling is associated with the defective bone development manifested in most CFC syndrome patients. In this study, induced pluripotent stem cells (iPSCs) were generated from dermal fibroblasts of a CFC syndrome patient having rapidly accelerated fibrosarcoma kinase B (BRAF) gain-of-function mutation. CFC-iPSCs were differentiated into mesenchymal stem cells (CFC-MSCs) and further induced to osteoblasts in vitro. The osteogenic defects of CFC-MSCs were revealed by alkaline phosphatase activity assay, mineralization assay, quantitative real-time polymerase chain reaction (qRT-PCR), and western blotting. Osteogenesis of CFC-MSCs was attenuated compared to wild-type (WT)-MSCs. In addition to activated ERK signaling, increased p-SMAD2 and decreased p-SMAD1 were observed in CFC-MSCs during osteogenesis. The defective osteogenesis of CFC-MSCs was rescued by inhibition of ERK signaling and SMAD2 signaling or activation of SMAD1 signaling. Importantly, activation of ERK signaling and SMAD2 signaling or inhibition of SMAD1 signaling recapitulated the impaired osteogenesis in WT-MSCs. Our findings indicate that SMAD2 signaling and SMAD1 signaling as well as ERK signaling are responsible for defective early bone development in CFC syndrome, providing a novel insight on the pathological mechanism and therapeutic targets.

Enhanced SMAD1 Signaling Contributes to Impairments of Early Development in CFC-iPSCs.

Cardio-facio-cutaneous (CFC) syndrome is a developmental disorder caused by constitutively active ERK signaling manifesting mainly from BRAF mutations. Little is known about the role of elevated ERK signaling in CFC syndrome during early development. Here, we show that both SMAD1 and ERK signaling pathways may contribute to the developmental defects in CFC syndrome. Induced pluripotent stem cells (iPSCs) derived from dermal fibroblasts of a CFC syndrome patient (CFC-iPSCs) revealed early developmental defects in embryoid body (EB) development, ß-catenin localization, and neuronal differentiation. Both SMAD1 and ERK signalings were significantly activated in CFC-iPSCs during EB formation. Most of the ß-catenin was dissociated from the membrane and preferentially localized into the nucleus in CFC-EBs. Furthermore, activation of SMAD1 signaling recapitulated early developmental defects in wild-type iPSCs. Intriguingly, inhibition of SMAD1 signaling in CFC-iPSCs rescued aberrant EB morphology, impaired neuronal differentiation, and altered ß-catenin localization. These results suggest that SMAD1 signaling may be a key pathway contributing the pathogenesis of CFC syndrome during early development.

Chronic total occlusion by stent fracture in Kawasaki disease: is recanalisation possible?

Despite various medications for Kawasaki disease, a small number of children have been undergoing interventions for severe coronary artery complications. Transcatheter intervention is a feasible alternative to coronary artery bypass grafting in a patient with chronic totally occluded lesion after Kawasaki disease, even by stent fracture.

Clinical spectrum and prognostic factors of pediatric ventricular tachycardia.

BACKGROUND: There have been no studies on the clinical characteristics and prognostic factors of pediatric ventricular tachycardia (VT). METHODS AND RESULTS: Eighty-one patients with pediatric VT were studied retrospectively at a single center. The median follow-up period was 6.0 years (0.7-23.5 years). Patients were categorized into 6 groups: idiopathic VT (IVT, n=37), catecholaminergic polymorphic VT (CPVT, n=10), congenital heart disease-associated VT (n=15), myocarditis-associated VT (n=8), cardiomyopathy-associated VT (CMP-VT, n=5) and miscellaneous. The age distribution of VT had 2 peaks (infant and teenager). VT with left bundle branch block configuration was more frequently nonsustained than VT with right bundle branch block configuration (61% vs 8%). Although 22% were asymptomatic, 38% experienced syncope or seizure and 16% had cardiac arrest. The overall mortality rate was 7.4%. The expected life span without cardiac arrest was <4 years in the CMP-VT group and the 10-year survival rate in CPVT patients was approximately 55%. Onset at infancy, monomorphic type and transcatheter/surgical ablation were related to the successful resolution of VT. Logistic regression analysis revealed that CPVT, CMP-VT, polymorphic VT and sustained VT were significantly correlated with death or cardiac arrest. CONCLUSIONS: The clinical features and prognosis of pediatric VT differed with the VT type, clinical categories and onset age. Accurate diagnosis and proper treatment according to the clinical categories may improve the outcome.

Manganese (II) induces chemical hypoxia by inhibiting HIF-prolyl hydroxylase: implication in manganese-induced pulmonary inflammation.

Manganese (II), a transition metal, causes pulmonary inflammation upon environmental or occupational inhalation in excess. We investigated a potential molecular mechanism underlying manganese-induced pulmonary inflammation. Manganese (II) delayed HIF-1alpha protein disappearance, which occurred by inhibiting HIF-prolyl hydroxylase (HPH), the key enzyme for HIF-1alpha hydroxylation and subsequent von Hippel-Lindau(VHL)-dependent HIF-1alpha degradation. HPH inhibition by manganese (II) was neutralized significantly by elevated dose of iron. Consistent with this, the induction of cellular HIF-1alpha protein by manganese (II) was abolished by pretreatment with iron. Manganese (II) induced the HIF-1 target gene involved in pulmonary inflammation, vascular endothelial growth factor (VEGF), in lung carcinoma cell lines.The induction of VEGF was dependent on HIF-1. Manganese-induced VEGF promoted tube formation of HUVEC. Taken together, these data suggest that HIF-1 may be a potential mediator of manganese-induced pulmonary inflammation.

Influence of nano-structured alumina coating on shear bond strength between Y-TZP ceramic and various dual-cured resin cements.

PURPOSE: The purpose of this study was to evaluate the effect of nano-structured alumina surface coating on shear bond strength between Y-TZP ceramic and various dual-cured resin cements. MATERIALS AND METHODS: A total of 90 disk-shaped zirconia specimens (HASS CO., Gangneung, Korea) were divided into three groups by surface treatment method: (1) airborne particle abrasion, (2) tribochemicalsilica coating, and (3) nano-structured alumina coating. Each group was categorized into three subgroups of ten specimens and bonded with three different types of dual-cured resin cements. After thermocycling, shear bond strength was measured and failure modes were observed through FE-SEM. Two-way ANOVA and the Tukey's HSD test were performed to determine the effects of surface treatment method and type of cement on bond strength (P<.05). To confirm the correlation of surface treatment and failure mode, the Chi-square test was used. RESULTS: Groups treated with the nanostructured alumina coating showed significantly higher shear bond strength compared to other groups treated with airborne particle abrasion or tribochemical silica coating. Clearfil SA Luting showed a significantly higher shear bond strength compared to RelyX ARC and RelyX Unicem. The cohesive failure mode was observed to be dominant in the groups treated with nano-structured alumina coating, while the adhesive failure mode was prevalent in the groups treated with either airborne particle abrasion or tribochemical silica coating. CONCLUSION: Nano-structured alumina coating is an effective zirconia surface treatment method for enhancing the bond strength between Y-TZP ceramic and various dual-cured resin cements.

Long-term consumption of sugar-sweetened beverage during the growth period promotes social aggression in adult mice with proinflammatory responses in the brain.

Overconsumption of sugar-sweetened beverages (SSBs) is known to be a key contributor to the obesity epidemic; however, its effects on behavioral changes are yet to be fully studied. In the present study, we examined the long-term effects of SSB on social aggression in mice. Three-week-old weaned mice started to drink either a 30 w/v% sucrose solution (S30), plain water (CT), or an aspartame solution with sweetness equivalent to the sucrose solution (A30) and continued to drink until they were 11-week-old adults. Aggressive behaviors were assessed by the resident-intruder test. We found that SSB significantly promoted social aggression, accompanied by heightened serum corticosterone and reduced body weight. To understand the underlying mechanism, we performed transcriptome analyses of brain. The profiles of mice on S30 were dramatically different from those on CT or A30. Transcriptional networks related to immunological function were significantly dysregulated by SSB. FACS analysis of mice on S30 revealed increased numbers of inflammatory cells in peripheral blood. Interestingly, the artificial sweetener failed to mimic the effects of sugar on social aggression and inflammatory responses. These results demonstrate that SSB promotes aggressive behaviors and provide evidence that sugar reduction strategies may be useful in efforts to prevent social aggression.

NPCARE: database of natural products and fractional extracts for cancer regulation.

BACKGROUND: Natural products have increasingly attracted much attention as a valuable resource for the development of anticancer medicines due to the structural novelty and good bioavailability. This necessitates a comprehensive database for the natural products and the fractional extracts whose anticancer activities have been verified. DESCRIPTION: NPCARE (http://silver.sejong.ac.kr/npcare) is a publicly accessible online database of natural products and fractional extracts for cancer regulation. At NPCARE, one can explore 6578 natural compounds and 2566 fractional extracts isolated from 1952 distinct biological species including plants, marine organisms, fungi, and bacteria whose anticancer activities were validated with 1107 cell lines for 34 cancer types. Each entry in NPCARE is annotated with the cancer type, genus and species names of the biological resource, the cell line used for demonstrating the anticancer activity, PubChem ID, and a wealth of information about the target gene or protein. Besides the augmentation of plant entries up to 743 genus and 197 families, NPCARE is further enriched with the natural products and the fractional extracts of diverse non-traditional biological resources. CONCLUSIONS: NPCARE is anticipated to serve as a dominant gateway for the discovery of new anticancer medicines due to the inclusion of a large number of the fractional extracts as well as the natural compounds isolated from a variety of biological resources.

Comparative Study of Bipolar Hemiarthroplasty for Femur Neck Fractures Treated with Cemented versus Cementless Stem.

PURPOSE: To compare and analyze clinical and radiologic outcomes of cemented versus cementless bipolar hemiarthroplasty for treatment of femur neck fractures. MATERIALS AND METHODS: A total of 180 patients aged 65 years and over older who underwent bipolar hemiarthroplasty for treatment of displaced femur neck fractures (Garden stage III, IV) from March 2009 to February 2014 were included in this study. Among the 180 patients, 115 were treated with cemented stems and 65 patients with cementless stems. Clinical outcomes assessed were: i) postoperative ambulatory status, ii) inguinal and thigh pain, and iii) complications. The radiologic outcome was femoral stem subsidence measured using postoperative simple X-ray. RESULTS: The cemented group had significantly lower occurrence of complications (postoperative infection, P=0.04) compared to the cementless group. There was no significant difference in postoperative ambulatory status, inguinal and thigh pain, and femoral stem subsidence. CONCLUSION: For patients undergoing bipolar hemiarthroplasty, other than complications, there was no statistically significant difference in clinical or radiologic outcomes in our study. Selective use of cemented stem in bipolar hemiarthroplasty may be a desirable treatment method for patients with poor bone quality and higher risk of infections.

Malfunction in Mitochondrial ß-Oxidation Contributes to Lipid Accumulation in Hepatocyte-Like Cells Derived from Citrin Deficiency-Induced Pluripotent Stem Cells.

Citrin deficiency (CD) is a recessive genetic disorder caused by mutations in the citrin gene SLC25A13. CD causes various symptoms related to nutrient metabolism such as urea cycle failure, abnormal amino acid levels, and fatty liver. To understand the pathophysiology of CD, the molecular phenotypes were investigated using induced pluripotent stem cells derived from fibroblasts of CD patient (CD-iPSCs). In this study, we demonstrate that aberrant mitochondrial ß-oxidation may lead to fatty liver in CD patients. CD-iPSCs normally differentiated into hepatocytes, similar to wild-type iPSCs (WT-iPSCs). However, hepatocytes derived from CD-iPSCs (CD-HLCs) did not exhibit ureogenesis. Cellular triglyceride and lipid granule levels were significantly increased in CD-HLCs compared with WT-HLCs. Peroxisome proliferator-activated receptor-α (PPAR-α) and its target genes which are involved in mitochondrial ß-oxidation were downregulated in CD-HLCs, and treatment with a PPAR-α agonist partially reduced the lipid accumulation in CD-HLCs. In addition, the mitochondria in CD-HLCs exhibited abnormal morphologies. Based on these observations, we conclude that the lipid accumulation in CD-HLCs results from dysfunctional mitochondrial ß-oxidation and abnormal mitochondrial structure.

Development of Analytical Method and Monitoring of Veterinary Drug Residues in Korean Animal Products.

This study was conducted to determine the residual amount of veterinary drugs such as meloxicam, flunixin, and tulathromycin in animal products (beef, pork, horsemeat, and milk). Veterinary drugs have been widely used in the rearing of livestock to prevent and treat diseases. A total of 152 samples were purchased from markets located in major Korean cities (Seoul, Busan, Incheon, Daegu, Daejeon, Gwangju, Ulsan and Jeju), including Jeju. Veterinary drugs were analyzed by liquid chromatography-tandem mass spectrometry according to the Korean Food Standards Code. The resulting data, which are located within 70-120% of recovery range and less than 20% of relative standard deviations, are in compliance with the criteria of CODEX. A total of five veterinary drugs were detected in 152 samples, giving a detection rate of approximately 3.3%; and no food source violated the guideline values. Our result indicated that most of the veterinary drug residues in animal products were below the maximum residue limits specified in Korea.

Late occurrence of adenosine-sensitive focal junctional tachycardia in complex congenital heart disease.

BACKGROUND: Although supraventricular tachycardia in complex congenital heart disease (CHD) has been reported after surgical repair, its exact electrophysiologic identification has been limited to intraatrial reentrant tachycardia (IART). Moreover, junctional tachycardia (JT) has not previously been described as a cause of late postoperative arrhythmia. METHODS AND RESULTS: Since 1993, a total of 12 patients with congenital heart disease presented with paroxysmal focal JT. The patients with only typical immediate postoperative junctional ectopic tachycardia were excluded. Medical records, standard electrocardiography and Holter monitoring were reviewed. An intracardiac electrophysiologic (EP) study was performed in 11 patients. Ten patients were in post-Fontan status (5.7% of total Fontan survivors). Focal JT occurred more frequently in heterotaxy syndrome among the Fontan survivors (7/52 vs. 3/124; P < 0.05). The commonest anatomy of the atrioventricular (AV) junction was complete AV canal in 8 patients. EP characteristics of focal JT were as follows: (1) various tachycardia mechanisms were identified (increased automaticity or a triggered mechanism in 6/11, and focal reentry in 5/11, including one concealed nodofascicular pathway) (2) ventriculoatrial conduction during tachycardia was either dissociation (7/12) or variable (5/12) (3) All JTs were terminated by adenosine. Class III antiarrhythmic agent was effective in 5/6. His bundle ablation was performed in one Fontan patient, who already had pacemaker because of accompanying intractable IART and sinus node dysfunction. CONCLUSION: Focal JT may be a source of late term supraventricular tachycardia in patients with complex CHD. The tachycardia mechanism was either automatic/triggered or reentrant. In all patients, JT was effectively terminated by adenosine.

Evaluation of effect of galvanic corrosion between nickel-chromium metal and titanium on ion release and cell toxicity.

PURPOSE: The purpose of this study was to evaluate cell toxicity due to ion release caused by galvanic corrosion as a result of contact between base metal and titanium. MATERIALS AND METHODS: It was hypothesized that Nickel (Ni)-Chromium (Cr) alloys with different compositions possess different corrosion resistances when contacted with titanium abutment, and therefore in this study, specimens (10×10×1.5 mm) were fabricated using commercial pure titanium and 3 different types of Ni-Cr alloys (T3, Tilite, Bella bond plus) commonly used for metal ceramic restorations. The specimens were divided into 6 groups according to the composition of Ni-Cr alloy and contact with titanium. The experimental groups were in direct contact with titanium and the control groups were not. After the samples were immersed in the culture medium - Dulbecco's modified Eagle's medium[DMEM] for 48 hours, the released metal ions were detected using inductively coupled plasma mass spectrometer (ICP-MS) and analyzed by the Kruskal-Wallis and Mann-Whitney test (P<.05). Mouse L-929 fibroblast cells were used for cell toxicity evaluation. The cell toxicity of specimens was measured by the 3-{4,5-dimethylthiazol-2yl}-2,5-diphenyltetrazolium bromide (MTT) test. Results of MTT assay were statistically analyzed by the two-way ANOVA test (P<.05). Post-hoc multiple comparisons were conducted using Tukey's tests. RESULTS: The amount of metal ions released by galvanic corrosion due to contact between the base metal alloy and titanium was increased in all of the specimens. In the cytotoxicity test, the two-way ANOVA showed a significant effect of the alloy type and galvanic corrosion for cytotoxicity (P<.001). The relative cell growth rate (RGR) was decreased further on the groups in contact with titanium (P<.05). CONCLUSION: The release of metal ions was increased by galvanic corrosion due to contact between base metal and titanium, and it can cause adverse effects on the tissue around the implant by inducing cytotoxicity.

Development of the SAIT single-port surgical access robot--slave arm based on RCM mechanism.

An innovative single-port surgical robot has recently been developed by the Samsung Advanced Institute of Technology (SAIT). The robot can reach various surgical sites inside the abdominal cavity from a single incision on the body. It has two 7-DOF surgical tools, a 3-DOF endoscope, a flexible hyper-redundant 6-DOF guide tube, and a 6-DOF manipulator. This paper primarily focuses on the manipulator, called a slave arm, which is capable of setting the location of a Remote Center Motion (RCM) point. Because the surgical tools can explore the abdominal area through a small incision point when the RCM point is aligned with the incision area, the RCM mechanism is an integral part of the manipulator for single-port surgery. The mechanical feature, operational principle, control method, and the system architecture of the slave arm are introduced in this paper. In addition, manipulation experiments conducted validate its efficacy.

Caffeic acid phenethyl ester is a potent inhibitor of HIF prolyl hydroxylase: structural analysis and pharmacological implication.

Caffeic acid phenethyl ester (CAPE) is an active component of propolis from honeybee. We investigated a potential molecular mechanism underlying a CAPE-mediated protective effect against ischemia/reperfusion (I/R) injury and analyzed the structure contributing to the CAPE effect. CAPE induced hypoxia-inducible factor-1 (HIF-1) alpha protein, concomitantly transactivating the HIF-1 target genes vascular endothelial growth factor and heme oxygenase-1, which play a protective role in I/R injury. CAPE delayed the degradation of HIF-1alpha protein in cells, which occurred by inhibition of HIF prolyl hydroxylase (HPH), the key enzyme for von Hippel-Lindau-dependent HIF-1alpha degradation. CAPE inhibition of HPH and induction of HIF-1alpha protein were neutralized by an elevated dose of iron. The catechol moiety, a chelating group, is essential for HPH inhibition, while hydrogenation of the double bond (-C=C-) in the Michael reaction acceptor markedly reduced potency. Removal of the phenethyl moiety of CAPE (substitution with the methyl moiety) severely deteriorated its inhibitory activity for HPH. Our data suggest that a beneficial effect of CAPE on I/R injury may be ascribed to the activation of HIF-1 pathway via inhibition of HPH and reveal that the chelating moiety of CAPE acted as a pharmacophore while the double bond and phenethyl moiety assisted in inhibiting HPH.

Cardiovascular anomalies in patients with chromosome 22q11.2 deletion: a Korean multicenter study.

BACKGROUND AND OBJECTIVES: The 22q11.2 deletion syndrome is reported with increasing frequency worldwide, and its clinical manifestations, including cardiovascular anomalies, appear to be more diverse than previously reported. The aim of this study was to determine the incidence and the pattern of cardiovascular anomalies in Korean patients with 22q11 deletion. METHODS: This study involved six Korean institutions. We reviewed the clinical records of patients and confirmed the presence of 22q11.2 deletion by fluorescent in situ hybridization (FISH). RESULTS: A total of 222 patients were examined and 190 (85.6%) patients had the cardiovascular abnormalities: 63.2% tetralogy of Fallot (TOF), 20.5% isolated ventricular septal defects (VSDs), 5.3% interrupted aortic arch type B (IAA B), 3.6% double outlet right ventricle (DORV), 3.6% atrial septal defects (ASDs) and 1.7% truncus arteriosus (TA). Of 168 patients with VSD, 69.6% had the perimembranous type, 11.9% the total conal defect type, 6.5% the subarterial type, 4.2% the muscular type and 1.2% the mixed type. A right aortic arch was observed in 50% of patients, and an aberrant subclavian artery was significantly more common with a right (30.9%) than a left (18.3%) aortic arch (p<0.05). CONCLUSIONS: A wide variety of cardiovascular anomalies were present in Korean patients with the 22q11.2 deletion.

Evaluation of viral clearance in the production of HPV-16 L1 virus-like particles purified from insect cell cultures.

Biopharmaceutical products produced from cell cultures have a potential for viral contamination from cell sources or from adventitious introduction during production. The objective of this study was to assess viral clearance in the production of insect cell-derived recombinant human papillomavirus (HPV)-16 type L1 virus-like particles (VLPs). We selected Japanese encephalitis virus (JEV), bovine viral diarrhea virus (BVDV), and minute virus of mice (MVM) as relevant viruses to achieve the aim of this study. A downstream process for the production of purified HPV-16 L1 VLPs consisted of detergent lysis of harvested cells, sonication, sucrose cushion centrifugation, and cesium chloride (CsCl) equilibrium density centrifugation. The capacity of each purification/treatment step to clear viruses was expressed as reduction factor by measuring the difference in log virus infectivity of sample pools before and after each process. As a result, detergent treatment (0.5% v/v, Nonidet P-40/phosphate-buffered saline) was effective for inactivating enveloped viruses such as JEV and BVDV, but no significant reduction (< 1.0 log(10)) was observed in the non-enveloped MVM. The CsCl equilibrium density centrifugation was fairly effective for separating all three relevant adventitious viruses with different CsCl buoyant density from that of HPV-16 L1 VLPs (JEV, BVDV, and MVM = 4.30, 3.10, > or = 4.40 log(10) reductions). Given the study conditions we used, overall cumulative reduction factors for clearance of JEV, BVDV, and MVM were > or = 10.50, > or = 9.20, and > or = 6.40 log(10) in 150 ml of starting cell cultures, respectively.

A case of congenital junctional ectopic tachycardia: diagnosis and successful radiofrequency catheter ablation in infancy.

It is difficult to make a definitive diagnosis of congenital junctional ectopic tachycardia (JET) in utero. We report a case in which congenial JET was suspected by fetal M-mode echocardiography. Fetal M-mode tracing of the atria and ventricle clearly showed a gradual acceleration of ventricular activity at the beginning of tachycardia, the warming-up sign of ectopic tachycardia, which was followed by simultaneous contractions of atrium and ventricle. This report also describes successful emergent radiofrequency catheter ablation of congenital JET in infancy with preservation of normal AV nodal conduction for this patient.

Pediatric radiofrequency catheter ablation: results of initial 100 consecutive cases including congenital heart anomalies.

Radiofrequency catheter ablation (RFCA) has recently become a management option for pediatric tachycardia. We reviewed the records of a total of 100 patients (aged 10 months to 19 yr) who had undergone RFCA, from March 2000 to June 2004. Types of arrhythmia (age, acute success rate) were as follows: atrioventricular reentrant tachycardia (AVRT, 9.0+/-3.7 yr, 66/67), atrioventricular nodal reentrant tachycardia (AVNRT, 13+/-2.5 yr, 16/16), ectopic atrial tachycardia (6.4+/-3.3 yr, 5/5), junctional ectopic tachycardia (10 month, 1/1), ventricular tachycardia (12+/-4.9 yr, 6/6), postsurgical intraatrial reentrant tachycardia (15.6+/-4.1 yr, 2/3), twin node tachycardia (4 yr, 0/1), and His bundle ablation (9 yr, 1/1). The age of AVNRT was older than that of AVRT (p=0.002). Associated cardiac disease was detected in 17 patients, including 6 univentricular patients, and 3 Ebstein's anomaly patients. RFCA for multiple accessory pathways required longer fluoroscopic times than did the single accessory pathway (53.9+/-4.8 vs. 36.2+/-24.1 min; p=0.03), and was associated with a higher recurrence rate (3/9 vs. 3/53; p=0.03). Regardless of the presence or absence of cardiac diseases, the overall acute success rate was 97% without major complications, the recurrence rate was 8.2%, and the final success rate was 97%. This experience confirmed the efficacy and safety of RFCA in the management of tachycardia in children.