Ruthenium Bottom Electrode Prepared by Electroplating for a High-density DRAM Capacitor

The possibility of Ru electroplating for application as the bottom electrode in high density dynamic random access memory ~DRAM! capacitors was investigated. Prior to Ru electroplating on a TiN substrate, HF cleaning and Pd activation were performed. Removal of Ti oxide from the TiN substrate by HF treatment enabled Pd activation, which enhanced the nucleation of Ru on TiN substrate. Optimized pretreatments led to a continuous Ru film deposition. The surface roughness was measured to be 4.4 nm at 45 nm Ru film on the bare substrate. Moreover Ru electroplating method was also applied to a capacitor node-type TiN wafer. The deposition rate of Ru on the patterned wafer was the same as that on a bare wafer. The film showed 93% step coverage and good adhesion, comparable to CVD Ru films

Photonic bandgaps of conformally coated structures

Polymeric molds of the layer-by-layer photonic crystal can be economically synthesized with a microtransfer molding technique. The refractive indices of these molds are low, preventing formation of a photonic bandgap. We find that such molds can be conformally coated with higher-index material. Photonic band calculations find structures in which conformally coated layer-by-layer molds have complete bandgaps for both titania and silicon coatings. Large stop bands exist in the 001 stacking direction. Feasibility of experimental conformal coating of the molds has been demonstrated with a titania-coated polyurethane mold, which shows optical features in agreement with simulations of reflection and transmission

Three-dimensional metallic photonic crystals fabricated by soft lithography for midinfrared applications

We present an efficient method of fabricating freestanding three-dimensional metallic photonic crystals using soft lithography. Low cost and ease of fabrication are achieved through gold sputter deposition on a freestanding woodpile polymer template. We compare experimental results to theoretical calculations for tetragonal and face-centered-tetragonal structures as a function of the number of layers. The photonic crystals behave like full metallic structures with a photonic band edge at a wavelength of 3.5μm. The rejection rates of the structures are about 10dB/layer.The following article appeared in Applied Physics Letters 88 (2006): 181112 and may be found at http://dx.doi.org/10.1063/1.2201621.</p

Replenishment of microRNA-188-5p restores the synaptic and cognitive deficits in 5XFAD Mouse Model of Alzheimer’s Disease

MicroRNAs have emerged as key factors in development, neurogenesis and synaptic functions in the central nervous system. In the present study, we investigated a pathophysiological significance of microRNA-188-5p (miR-188-5p) in Alzheimer’s disease (AD). We found that oligomeric Aβ(1-42) treatment diminished miR-188-5p expression in primary hippocampal neuron cultures and that miR-188-5p rescued the Aβ(1-42)-mediated synapse elimination and synaptic dysfunctions. Moreover, the impairments in cognitive function and synaptic transmission observed in 7-month-old five familial AD (5XFAD) transgenic mice, were ameliorated via viral-mediated expression of miR-188-5p. miR-188-5p expression was down-regulated in the brain tissues from AD patients and 5XFAD mice. The addition of miR-188-5p rescued the reduction in dendritic spine density in the primary hippocampal neurons treated with oligomeric Aβ(1-42) and cultured from 5XFAD mice. The reduction in the frequency of mEPSCs was also restored by addition of miR-188-5p. The impairments in basal fEPSPs and cognition observed in 7-month-old 5XFAD mice were ameliorated via the viral-mediated expression of miR-188-5p in the hippocampus. Furthermore, we found that miR-188 expression is CREB-dependent. Taken together, our results suggest that dysregulation of miR-188-5p expression contributes to the pathogenesis of AD by inducing synaptic dysfunction and cognitive deficits associated with Aβ-mediated pathophysiology in the disease

Percutaneous placement of self-expandable metallic stents in patients with obstructive jaundice secondary to metastatic gastric cancer after gastrectomy

OBJECTIVE: To evaluate the outcomes of patients undergoing percutaneous placements of a biliary stent for obstructive jaundice secondary to metastatic gastric cancer after gastrectomy. MATERIALS AND METHODS: Fifty patients (mean age, 62.4 years; range, 27-86 years) who underwent percutaneous placements of a biliary stent for obstructive jaundice secondary to metastatic gastric cancer after gastrectomy were included. The technical success rate, clinical success rate, complication rate, stent patency, patient survival and factors associated with stent patency were being evaluated. RESULTS: The median interval between the gastrectomy and stent placement was 23.1 months (range, 3.9-94.6 months). The 50 patients received a total of 65 stents without any major procedure-related complications. Technical success was achieved in all patients. The mean total serum bilirubin level, which had been 7.19 mg/dL ± 6.8 before stent insertion, decreased to 4.58 mg/dL ± 5.4 during the first week of follow-up (p < 0.001). Clinical success was achieved in 42 patients (84%). Percutaneous transhepatic biliary drainage catheters were removed from 45 patients (90%). Infectious complications were noted in two patients (4%), and stent malfunction occurred in seven patients (14%). The median stent patency was 233 ± 99 days, and the median patient survival was 179 ± 83 days. Total serum bilirubin level after stenting was an independent factor for stent patency (p = 0.009). CONCLUSION: Percutaneous transhepatic placement of a biliary stent for obstructive jaundice secondary to metastatic gastric cancer after gastrectomy is a technically feasible and clinically effective palliative procedure

Transient receptor potential channel TRPV4 mediates TGF-β1-induced differentiation of human ventricular fibroblasts

Background: Cardiac fibroblasts (CFs) are principal extracellular matrix-producing cells. In response to injury, CFs transdifferentiate into myofibroblasts. Intracellular calcium (Ca2+) signaling, involved in fibroblast proliferation and differentiation, is activated in fibroblasts through transient receptor potential (TRP) channels, but the function of these channels has not been investigated in human ventricular CFs. Under evaluation in this study, was the role of TRP channels in the differentiation of human ventricular CFs induced by transforming the growth factor beta (TGF-β), a pro-fibrotic cytokine. Methods: Human ventricular CFs were used in this study. The differentiation of CFs into myofibroblast was induced with TGF-β and was identified by the expression of smooth muscle actin. Results: Results indicate that Ca2+ signaling was an essential component of ventricular CF dif­ferentiation. CFs treated with TGF-β demonstrated increased expression of a TRP channel, TRPV4, both at the mRNA and protein levels, which corresponded with CF-myofibroblast trans-differentiation, as evidenced by the upregulation of α-smooth muscle actin, a myofibroblast marker, and plasminogen activator inhibitor-1, which are fibrogenesis markers. An agonist of TRPV4 induced the conversion of CFs into myofibroblasts, whereas it’s antagonist as well a Ca2+ chelating agent reduced it, indicating that the Ca2+ influx throughTRPV4 is required for CF trans-differentiation. Overall, these results dem­onstrate that TRPV4-mediated Ca2+ influx participates in regulating the differentiation of human ventricular CFs into myofibroblasts through the MAPK/ERK pathway. Conclusions: Overall, these results demonstrate that TRPV4-mediated Ca2+ influx participates in regulating the differentiation of human ventricular CFs into myofibroblasts through the MAPK/ERK pathway

Antiallodynic Effects of Acupuncture in Neuropathic Rats

Peripheral nerve injury often results in abnormal neuropathic pain such as allodynia or hyperalgesia. Acupuncture, a traditional Oriental medicine, has been used to relieve pain and related symptoms. However, the efficiency of acupuncture in relieving neuropathic pain is not clear. The aim of this study was to investigate the anti-allodynic effects of acupuncture through behavioral and electrophysiological examinations. Male Sprague-Dawley rats were subjected to neuropathic surgery consisting of a tight ligation and transection of the left tibial and sural nerves, under pentobarbital anesthesia. The acupuncture experiment consisted of four different groups, one treated at each of three different acupoints (Zusanli (ST36), Yinlingquan (SP9), and a sham-acupoint) and a control group. Behavioral tests for mechanical allodynia and cold allodynia were performed for up to two weeks postoperatively. Extracellular electrophysiological recordings were made from the dorsal roots using platinum wire electrodes. Mechanical and cold allodynia were significantly reduced after acupuncture treatment at the Zusanli and Yinlingquan acupoints, respectively. Electrophysiological neural responses to von Frey and acetone tests were also reduced after acupuncture at the same two acupoints. These results suggest that acupuncture may be beneficial in relieving neuropathic pain

Meta-analysis of the Association between HLA-DRB1 Allele and Rheumatoid Arthritis Susceptibility in Asian Populations

The aims of this study were to summarize results on the association of HLA-DRB1 with rheumatoid arthritis (RA) in Asians and to determine if the shared epitope (SE) hypothesis could explain the meta-analysis results. Among the papers published between January 1987 and July 2006 on RA susceptibility in Asian-Mongoloid populations (Korean, Japanese, Chinese, and Thai), 12 were selected for the meta-analysis. Mongoloid-Asian patients with RA had significantly higher frequencies of HLA-DRB1*0101, *0401, *0410, and *1001 than controls (OR 1.5-2.1, p<0.05 for association). When analyses were restricted to more ethnically homogeneous populations, HLA-DRB1*0405 showed a significant susceptibility to RA in Koreans (OR 5.65, 95% CI 4.32-7.39), whereas the HLA-DRB1*0301, *0403, *0406, *0701, *1301, and *1405 alleles showed protective association with RA (OR 0.32-0.70, p<0.05 for association). In conclusion, it was found that HLA-DRB1 *0101, *0401, *0405, *0410, and *1001 are susceptible, while HLA-DRB1*0301, *0403, *0406, *0701, *1301, and *1405 are protective in Asian-Mongoloids. All the RA-associated alleles except DRB1*0301 could be explained by the structural model supporting the SE hypothesis that RA susceptibility is determined by the combination of amino acid residues at HLA-DR β71 and β74, not by β71 alone

A Nationwide Survey of Lymphangioleiomyomatosis in Korea: Recent Increase in Newly Diagnosed Patients

In 2007, the Korean Interstitial Lung Disease Society had collected clinical data of patients who have diagnosed as Lymphangioleiomyomatosis (LAM) since 1990 through nationwide survey, which showed that LAM patients had increased sharply after 2004. The present study was performed to show the clinical features of Korean patients with LAM, and to establish the reason for the recent increase in the diagnosis. All 63 patients were women and the mean age at diagnosis was 36 yr. The most common presenting symptom was dyspnea and 8 patients had tuberous sclerosis complex. The survival rate at 5 yr after diagnosis was 84%. Compared with patients diagnosed after 2004 (n=34), the patients diagnosed before 2004 (n=29) complained with dyspnea more (P=0.016) and had lower FEV1% predicted (P=0.003), and DLco% predicted (P=0.042). The higher proportion of patients diagnosed after 2004 showed the normal chest radiography, and they were detected by routine chest CT screening (P=0.016). This study showed that clinical features of Korean patients with LAM were not different from those reported elsewhere. It is concluded that the reason for the increase of newly diagnosed patients is the result of increase in detection of the early stage LAM by the widespread use of chest CT screening

Impact of multivessel versus single-vessel disease on the association between low diastolic blood pressure and mortality after acute myocardial infarction with revascularization

Background: Previous studies demonstrated a J-shaped relationship between low diastolic blood pressure (DBP) and adverse clinical outcomes in patients with acute myocardial infarction (AMI) that was sensitive to revascularization. Hypothesized herein, was that this relationship differs between patients with multivessel disease (MVD) and those with single-vessel disease due to differing degrees of myocardial ischemic burden. Methods: Among 9,983 AMI patients from the Korea Acute Myocardial Infarction Registry database who underwent percutaneous coronary intervention and were followed up for a median duration of 3.2 years, average on-treatment DBP was calculated at admission, discharge, and every scheduled visit and divided into these parameters: &lt; 70 mmHg, 70–74 mmHg, 75–79 mmHg, and ≥ 80 mmHg. The relationship between average on-treatment DBP and clinical outcomes including all-cause death, cardiovascular (CV) death, non-CV death, and hospitalization for heart failure was analyzed using the Cox regression models adjusted for clinical covariates. Results: In patients with MVD, all-cause death (hazard ratio [HR]: 1.47; 95% confidence interval [CI]: 1.06–2.04, p = 0.012) and CV death (HR: 1.59; 95% CI: 1.02–2.46, p = 0.027) were significantly increased in patients with a DBP &lt; 70 mmHg, showing a J-shaped relationship. However, these findings were not significant for single-vessel disease. On a sensitivity analysis excluding subjects with a baseline SBP &lt; 120 mmHg, an increased risk of a low DBP &lt; 70 mmHg remained in MVD. Conclusions: The J-shaped relationship between low DBP and adverse clinical outcomes in AMI patients who underwent revascularization persisted in MVD, which has a high ischemic burden. These high-risk patients require cautious treatment