Radiofrequency ablation versus surgical resection for multiple HCCs meeting the Milan criteria: propensity score analyses of 10-year therapeutic outcomes.

AIM: To assess the long-term therapeutic outcomes of radiofrequency ablation (RFA) versus surgical resection (SR) as a first-line treatment for patients meeting the Milan criteria with multiple hepatocellular carcinomas (HCCs). MATERIALS AND METHODS: This retrospective study was approved by the institutional review board and the requirement for informed consent was waived. Between January 2004 and December 2009, among 3,441 patients with treatment-naive HCCs, 88 patients meeting the Milan criteria with multiple HCCs (Barcelona Clinic Liver Cancer [BCLC] A stage) who underwent either RFA (n=62) or SR (n=26) were included. Recurrence-free survival (RFS) and overall survival (OS) rates were compared by using propensity score matching. In addition, multivariate analysis was performed for assess the prognostic factor. RESULTS: Matching yielded 20 matched pairs of patients. In the two matched groups, the RFS rates were 30% and 30% at 5- and 10-years, respectively, in the RFA group and 60% and 48.6% in the SR group (p=0.054). The corresponding OS rates were 63.3% and 46.1% in the RFA group and 100% and 73.6% in the SR group, respectively (p=0.061). In multivariate analysis, treatment type was independently associated with RFS (hazard ratio [HR]=0.51; p=0.043) whereas it was not a statistically significant factor for OS (HR=0.50; p=0.088). CONCLUSION: In patients meeting the Milan criteria with multiple HCCs (BCLC A stage), SR may provide better RFS compared to RFA.

Local tumour progression after loco-regional therapy of hepatocellular carcinomas: value of fusion imaging-guided radiofrequency ablation.

AIM: To assess the value of fusion imaging of real-time ultrasonography (US) with liver computed tomography (CT)/magnetic resonance imaging (MRI) images for planning US of radiofrequency ablation (RFA) in improving conspicuity of the lesions and reducing false-positive detection of local tumour progression (LTP) found after transcatheter arterial chemoembolization (TACE) or RFA of hepatocellular carcinoma (HCC). MATERIALS AND METHODS: This study was approved by the institutional review board and informed consent was waived. Fifty patients with LTP (mean ± SD, 1.5 ± 0.6 cm; range 0.5-3 cm) detected at follow-up CT or MRI were included. Planning US was performed by two radiologists using conventional US first and fusion imaging later in the same session. False-positive detection rates were assessed using conventional US based on the results of fusion imaging. The number cases of initially invisible tumours on conventional US that became visible after image fusion were also evaluated. The true-positive detection rate and conspicuity scores of the index tumours were compared between conventional US and fusion imaging. RESULTS: On conventional US, 40 (80%) out of 50 HCCs with LTP were identified. However, the false-positive detection rate of conventional US was 12.5% (5/40). Out of 10 initially invisible HCCs with LTP on conventional US, six (60%) became visible after image fusion. The true-positive detection rate on conventional US was 70% (35/50), whereas it was increased to 92% (46/50) after image fusion (p = 0.0026). CONCLUSION: Fusion imaging can improve the conspicuity of lesions and reduce the false-positive detection of LTP after TACE or RFA.

Reduced serum uric acid levels in neuromyelitis optica: serum uric acid levels are reduced during relapses in NMO.

OBJECTIVES: Uric acid (UA), a product of purine metabolism, is known to be reduced in patients with various neurological disorders including multiple sclerosis (MS). However, it has still remained unclear whether there is a close relationship between UA and neuromyelitis optica (NMO). The aim of this study was to investigate the association between serum UA levels and disease activity in NMO. METHODS: Retrospective analysis was made of blood samples during relapses (n = 48) and during stable disease (n = 49) from 20 patients with NMO. As controls, 59 blood samples during relapses from 39 patients with MS and 90 samples from healthy subjects were obtained. Spine magnetic resonance images (MRIs) performed during relapses (n = 24) in NMO were analysed. RESULTS: The results indicated that UA levels during relapses in NMO were significantly lower compared to healthy subjects (P < 0.01), but not different from those during relapses in MS, and that reduced UA levels during relapses in NMO were normalized during stable disease. However, UA levels during relapses were not correlated with Gd enhancement in spine MRI. CONCLUSION: UA levels are associated with clinical disease status in patients with NMO. Further investigations are recommended to elucidate the role of UA as a biomarker of disease activity in NMO.

Survival and predictors of outcomes in non-HIV-infected patients with extensively drug-resistant tuberculosis.

SETTING: A tuberculosis (TB) referral hospital in South Korea. OBJECTIVE: To evaluate predictors of treatment outcomes and survival among non-human immunodeficiency virus (HIV) infected patients with extensively drug-resistant TB (XDR-TB). DESIGN: Patients who were diagnosed with XDR-TB at the National Masan Tuberculosis Hospital from January 2001 to December 2005 were included in this study. We conducted a retrospective review of their medical records and mortality data. RESULTS: A total of 176 non-HIV-infected patients with XDR-TB were included. TB-related mortality was 48% (84/176), and the median survival time from the diagnosis date of XDR-TB was 51 months (range 0-127, 95%CI 32.53-69.47). Cure and treatment completion were classified as favourable outcome and treatment failure, death during treatment and default as poor outcome. Previous TB treatment with second-line drugs (aOR 2.76, 95%CI 1.02-7.44) and cavitary disease (aOR 3.01, 95%CI 1.12-8.08) were independent risk factors for poor outcome. Use of linezolid (aOR 0.10, 95%CI 0.01-0.69) and surgical resection (aOR 0.18, 95%CI 0.04-0.78) were associated with favourable outcome. CONCLUSION: There was high mortality in non-HIV-infected patients with XDR-TB at a TB referral hospital in South Korea. Adjunctive surgical treatment and linezolid improved the outcome for selected patients with XDR-TB.

Fabrication and design of metal nano-accordion structures using atomic layer deposition and interference lithography.

Metal nanostructures have attractive electrical and thermal properties as well as structural stability, and are important for applications in flexible conductors. In this study, we have developed a method to fabricate and control novel complex platinum nanostructures with accordion-like profile using atomic layer deposition on lithographically patterned polymer templates. The template removal process results in unique structural transformation of the nanostructure profile, which has been studied and modeled. Using different template duty cycles and aspect ratios, we have demonstrated a wide variety of cross-sectional profiles from wavy geometry to pipe array patterns. These complex thin metal nanostructures can find applications in flexible/stretchable electronics, photonics and nanofluidics.

Measurement of levels of fractional exhaled nitric oxide in patients with pulmonary tuberculosis.

SETTING: The role of fractional exhaled nitric oxide (FeNO) in the diagnosis and treatment of pulmonary tuberculosis (PTB) is uncertain. OBJECTIVE: To examine the value of FeNO as a biomarker for PTB. DESIGN: Baseline FeNO levels were compared in 69 PTB patients and 118 healthy controls. The correlation between baseline FeNO levels and clinical variables of tuberculosis were studied. FeNO levels were checked twice in the PTB group, at diagnosis and after 2 months of anti-tuberculosis medication, and factors affecting changes in FeNO levels after treatment were analysed. RESULTS: FeNO levels were not significantly different in the PTB group and controls (mean ± standard deviation 27.7 ± 17.6 parts per billion [ppb] vs. 27.0 ± 10.8 ppb, P = 0.531). In a multivariate regression analysis, no variable was shown to affect FeNO levels at diagnosis. FeNO levels did not significantly change after 2 months of treatment (26.8 ± 18.3 ppb vs. 24.0 ± 10.7 ppb, P = 0.257). Only PTB with a high FeNO level (>25 ppb) was related to a decline in FeNO levels after 2 months of treatment. CONCLUSION: FeNO levels do not appear to be affected in PTB patients.

Do membrane-bound enzymes access their substrates from the membrane or aqueous phase: interfacial versus non-interfacial enzymes.

For membrane-bound enzymes that act on substrates that partition between the membrane and aqueous phases, it is possible to imagine two fundamentally different mechanisms. Interfacial enzymes must access their substrate from the membrane phase, in other words substrate in the membrane binds directly to the active site of the enzyme at the membrane without mixing with substrate molecules in the aqueous phase. On the other hand, non-interfacial enzymes, either bound to membranes or present in the aqueous phase, must access their substrates from the aqueous phase, i.e. substrate in the aqueous phase binds directly to the enzyme without mixing with substrates in the membrane phase. An interfacial mechanism for some enzymes including secreted and cytosolic phospholipase A(2) and phosphoinositide 3'-hydroxykinase was rigorously proven by demonstrating that these enzymes processively hydrolyze many phospholipids without desorbing from the surface of vesicles (scooting mode). The non-interfacial mechanism is more difficult to establish because it cannot be addressed by steady-state kinetics. Using a pre-steady-state method in which the enzymatic velocity is measured during the time it takes for substrate to exchange between vesicles, a non-interfacial mechanism was proven for vesicle-bound plasma platelet activating factor acetylhydrolase. This enzyme prefers more water-soluble phospholipids such as those with sn-2 acetyl or oxidatively truncated fatty acyl chains, and this is readily explained by the mandatory access of substrate from the aqueous phase.

Evaluation of penetration effect of resin infiltrant using optical coherence tomography.

OBJECTIVE: The aims of this in vitro study were to investigate whether optical coherence tomography (OCT) could analyze infiltration of resin infiltrant (RI) into early dental caries (EC), and to confirm the correlation between the results of OCT and confocal laser scanning microscopy (CLSM) for evaluation of RI infiltration into EC. METHODS: Sound bovine permanent teeth were used to produce sixty specimens by making two windows on the teeth. Each 20 specimens were demineralized for 20, 30, and 40 days, and the RI was treated on one of the windows. As a result, the images of the fifty-two specimens were taken by OCT and CLSM. The demineralized lesion depth (LDOCT and LDCLSM) and the infiltrated depth of RI into lesion (IDOCT and IDCLSM) obtained from the OCT and the CLSM were analyzed. The correlations between the LDOCT and the LDCLSM, and between the IDOCT and the IDCLSM, were analyzed by Pearson correlation and intra-class correlation. Also, Bland-Altman plot was constructed to assess the agreement between the IDOCT and the IDCLSM, and the IDOCT divided by refractive index of RI and the IDCLSM. RESULTS: The Pearson correlation coefficient and intra-class correlation of 0.75 and 0.83 (95% CI: 0.71-0.91) respectively were confirmed between the LDOCT and the LDCLSM (p<0.001), and 0.59 and 0.71 (95% CI: 0.50-0.84) respectively were observed between the IDOCT and the IDCLSM (p<0.001). The lower bias was confirmed in Bland-Altman plot between adjusted IDOCT and the IDCLSM than between the IDOCT and the IDCLSM. CONCLUSION: The OCT was the promising quantitative evaluation method for RI penetrated into EC. CLINICAL SIGNIFICANCE: The OCT would be used as a nondestructive and real-time evaluation method for RI penetrated into EC on clinical procedure.

Distant metastasis of intraosseous dentinogenic ghost cell tumour to the donor site of a bone graft.

A dentinogenic ghost cell tumour (DGCT) is an extremely rare odontogenic tumour which is considered as a solid, neoplastic variant of calcifying odontogenic cyst. Intraosseous DGCTs are more aggressive than extraosseous DGCTs and have a high propensity for local recurrence. This report describes a case of a diagnosis of recurrent DGCT at the primary site and a distant donor site. A 25-year-old female patient visited a dental hospital for a complaint of facial swelling for the previous month. Incisional biopsy was performed and the specimen was diagnosed as DGCT. Partial mandibulectomy for tumour resection and iliac bone graft was performed. 2 years later, the tumour recurred on the mandible and iliac bone. The recurrent lesion on the donor site was diagnosed as metastasized DGCT. This report highlights the possibility of distant metastasis occurring at a graft donor site.

Effectiveness of bone scans in the diagnosis of osteoarthritis of the temporomandibular joint.

OBJECTIVE: The objective of this study was to evaluate the usefulness of bone scan procedures for the diagnosis of temporomandibular joint (TMJ) osteoarthritis. METHODS: From February 2009 to June 2009, 22 patients (4 males and 18 females) from Seoul National University Bundang Hospital, Republic of Korea, were diagnosed with TMJ disorder. They were examined by clinical examination, plain radiograph and bone scan and were categorized into three groups: normal, internal derangement and osteoarthritis. TMJ uptake ratios and asymmetrical indices were calculated. RESULTS: There were no significant differences in uptake ratios associated with pain and bone change. However, significant results were obtained when comparing uptake ratios between the osteoarthritis and non-osteoarthritis groups. CONCLUSION: It was concluded from this study that bone scans may help to diagnose osteoarthritis when increased uptake ratios are observed.

Frequency of adverse reactions to first- and second-line anti-tuberculosis chemotherapy in a Korean cohort.

OBJECTIVE: To determine the frequency of and risk factors for major adverse drug reactions (MADRs) associated with anti-tuberculosis treatment at a tuberculosis (TB) referral hospital in the Republic of Korea. METHODS: Data from an ongoing natural history cohort study were analyzed for permanent regimen changes due to adverse drug reactions and confirmed by chart review. RESULTS: Among 655 subjects, there were 132 MADRs in 112 (17%) subjects. The most common MADRs were gastrointestinal (n = 53), musculoskeletal (n = 22), psychiatric (n = 10), visual (n = 9) and peripheral neuropathic (n = 8). MADRs were more frequent in subjects being treated with second-line regimens (16%) compared to first-line regimens (2.5%). Drugs frequently associated with MADRs were amikacin (3/10, 30%), linezolid (8/29, 28%), para-aminosalicylic acid (47/192, 24%), pyrazinamide (31/528, 5.8%), macrolides (2/44, 4.5%) and cycloserine (12/272, 4.4%). Fluoroquinolones accounted for a single MADR (1/377, 0.003%), despite widespread usage. In multivariate analysis, infection with multi- or extensively drug-resistant disease and previous history of anti-tuberculosis treatment were risk factors for MADR, with adjusted hazard ratios of respectively 2.2 (P = 0.02) and 1.6 (P = 0.04). CONCLUSION: MADRs are common during anti-tuberculosis chemotherapy in this population, occurring in more than one in six subjects. New and less toxic agents to treat drug-resistant TB are urgently needed.

The addition of nano-sized hydroxyapatite to a sports drink to inhibit dental erosion: in vitro study using bovine enamel.

OBJECTIVES: This study examined the dental erosion and demineralization potential of a sports drink containing nano-sized hydroxyapatite (nano-HA) as an additive. METHODS: The experimental solutions were Powerade (PA) alone and PA with 0.05%, 0.10%, and 0.25% nano-HA. The pH, titratable acidity, and calcium and phosphate content of each solution were analysed, and the degree of saturation with respect to the dental enamel (DS(En)) was obtained. Twelve sound bovine enamel specimens for each group were treated in accordance with the pH-cycling schedule which had 60min treatment with experimental solution per day for 7 days. The erosion potential was determined from the changes in surface micro hardness (SMH), the depths of erosion and demineralized layer using confocal laser scanning microscopy (CLSM), and the morphological changes to the tooth surface were examined with scanning electron microscopy (SEM) after pH-cycling. RESULTS: pH and DS(En) increased with increasing nano-HA concentration in the drinks, whereas the titratable acidity decreased. There were significant differences in the SMH between the PA alone and >0.10% nano-HA groups (p<0.001). Although the PA alone group showed a pronounced erosion depth, CLSM showed no erosion depth in 0.25% nano-HA group. SEM showed an intact surface with increasing nano-HA concentration in the drinks. In conclusion, dental erosion was effectively prevented with increase of adding concentration of nano-HA, and a sports drink containing 0.25% nano-HA might prevent dental erosion.

Attenuation of hemodynamic responses to laryngoscopy and tracheal intubation during rapid sequence induction: remifentanil vs. lidocaine with esmolol.

AIM: This study was designed to compare the effectiveness of remifentanil vs. a lidocaine-esmolol combination in blunting the hemodynamic response to laryngoscopy and intubation during rapid sequence induction using thiopental and rocuronium in normotensive patients. METHODS: Sixty-six patients with American Society of Anesthesiologists (ASA) physical status class I who required tracheal intubation for elective surgery were randomly assigned to one of two groups. Group R received 0.9% saline 10 ml and remifentanil 1 microg/kg. Group LE received lidocaine 1.5 mg/kg and esmolol 1.0 mg/kg. Anesthesia was induced with thiopental sodium 5 mg/kg, followed by rocuronium 1.0 mg/kg. Mean arterial pressure and heart rate were recorded at baseline, after induction, immediately after intubation and every minute for five minutes after intubation. RESULTS: Changes in mean arterial pressure over time between the two groups were significantly different (P<0.0001). The maximum pressor response was observed immediately after intubation, at which time the mean arterial pressure change from baseline in group LE (29.7%) (95% confidence interval [CI]: 116.1, 121.9) was higher than that in group R (4.4%) (95% CI: 92.9, 98.5) (P<0.0001). Two patients in group R and 15 patients in group LE developed hypertension (odds ratio [OR]: 0.064) (P<0.001). Changes in heart rate over time between the two groups were not significantly different (P=0.465). CONCLUSION: The results of this study show that remifentanil 1 mg/kg is more effective than the combination of lidocaine 1.5 mg/kg and esmolol 1 mg/kg for attenuating the hemodynamic responses to rapid sequence intubation.

Sphingosine-1-phosphate signaling in human submandibular cells.

Sphingosine-1-phosphate (S1P) is a significant lipid messenger modulating many physiological responses. S1P plays a critical role in autoimmune disease and is suggested to be involved in Sjögren's syndrome pathology. However, the mechanism of S1P signaling in salivary glands is unclear. Here we studied the effects of S1P on normal human submandibular gland cells. S1P increased levels of the intracellular Ca(2+) concentration ([Ca(2+)](i)), which was inhibited by pre-treatment with U73122 or 2-aminoethoxydiphenyl borate (2-APB). Pre-treated S1P did not inhibit subsequent carbachol-induced [Ca(2+)](i) increase, which suggests that S1P and muscarinic signaling are independent of each other. S1P1, S1P2, and S1P3 receptors SphK1 and SphK2 were commonly expressed in human salivary gland cells. S1P, but not carbachol, induces the expression of interleukin-6 and Fas. Our results suggest that S1P triggers Ca(2+) signaling and the apoptotic pathway in normal submandibular gland cells, which suggests in turn that S1P affects the progression of Sjögren's syndrome.

Sjogren's syndrome myelopathy: spinal cord involvement in Sjogren's syndrome might be a manifestation of neuromyelitis optica.

OBJECTIVE: To evaluate clinical characteristics, aquaporin (AQP)-4 antibody results, and probability of developing symptoms of neuromyelitis optica (NMO) in patients with Sjögren's syndrome myelopathy (SSM). METHODS: We identified eight patients with spinal cord involvement from 112 patients with Sjögren's syndrome (SS) referred to the neurology department. The clinical characteristics and AQP-4 antibody status, based on immunoprecipitation of EGFP-tagged AQP-4, of the patients with SSM were assessed. RESULTS: All patients with SSM had extensive spinal cord lesions, high mean annual relapse rates, and poor response to steroid treatment. Of the eight patients with SSM, seven patients satisfied the revised diagnostic criteria for NMO or showed positive results from AQP-4 antibody testing; one patient had incomplete follow-up. The clinical manifestations and AQP-4 autoantibody status of patients with SSM did not differ significantly from those of NMO patients without SS. CONCLUSION: All patients with SSM had poor prognosis with high mean annual relapse rates, and most seemed to have the clinical and immunological characteristics of NMO. Early aggressive immune therapies should be considered in patients with SSM irrespective of the presence or absence of optic neuritis.

Brain abnormalities in Sjogren syndrome with recurrent CNS manifestations: association with neuromyelitis optica.

BACKGROUND AND OBJECTIVES: Optic neuritis or longitudinally extensive myelitis in Sjogren syndrome (SS) suggests a neuromyelitis optica spectrum disorder (NMOSD). However, brain abnormalities of SS remain to be elucidated for the association with neuromyelitis optica (NMO). METHODS: Twelve primary SS patients (all women, 42 +/- 13.2 years) who had recurrent central nervous system (CNS) manifestations with brain involvement were retrospectively identified. Brain MRI, and neurologic and serologic findings were analyzed with the measurement of anti-aquaporin-4 antibody (AQP4-Ab). RESULTS: All patients showed brain lesions characteristic of NMO as follows: 1) the involved sites adjacent to the third and fourth ventricles and in the posterior limb of the internal capsule, 2) unique configurations, such as the longitudinal course from the internal capsule to the midbrain, large cerebral or cerebellar lesions over 3 cm, and cavity-like formations. AQP4-Ab was positive in six of eight patients tested, and all the seropositive patients showed lesions with increased diffusion, suggestive of vasogenic edema. Four patients met the revised criteria of NMO, and nine had features of NMOSDs. Of the remaining three patients showing only brain involvement, one had AQP4-Ab. CONCLUSIONS: This study demonstrates that SS patients with recurrent CNS involvement have brain abnormalities characteristic of NMO and AQP4-Ab in Korea. The presence of AQP4-Ab in one SS patient with only brain involvement may suggest that the coexistence of NMO should be explored in SS patients with recurrent CNS manifestations, even without optic neuritis or myelitis.

Platelet-activating factor acetylhydrolases: broad substrate specificity and lipoprotein binding does not modulate the catalytic properties of the plasma enzyme.

Platelet-activating factor acetylhydrolases (PAF-AHs) are a group of enzymes that hydrolyze the sn-2 acetyl ester of PAF (phospholipase A(2) activity) but not phospholipids with two long fatty acyl groups. Our previous studies showed that membrane-bound human plasma PAF-AH (pPAF-AH) accesses its substrate only from the aqueous phase, which raises the possibility that this enzyme can hydrolyze a variety of lipid esters that are partially soluble in the aqueous phase. Here we show that pPAF-AH has broad substrate specificity in that it hydrolyzes short-chain diacylglycerols, triacylglycerols, and acetylated alkanols, and displays phospholipase A(1) activity. On the basis of all of the substrate specificity results, it appears that the minimal structural requirement for a good pPAF-AH substrate is the portion of a glyceride derivative that includes an sn-2 ester and a reasonably hydrophobic chain in the position occupied by the sn-1 chain. In vivo, pPAF-AH is bound to high and low density lipoproteins, and we show that the apparent maximal velocity for this enzyme is not influenced by lipoprotein binding and that the enzyme hydrolyzes tributyroylglycerol as well as the recombinant pPAF-AH does. Broad substrate specificity is also observed for the structurally homologous PAF-AH which occurs intracellularly [PAF-AH(II)] as well as for the PAF-AH from the lower eukaryote Physarum polycephalum although pPAF-AH and PAF-AH(II) tolerate the removal of the sn-3 headgroup better than the PAF-AH from P. polycephalum does. In contrast, the intracellular PAF-AH found in mammalian brain [PAF-AH(Ib) alpha 1/alpha 1 and alpha 2/alpha 2 homodimers] is more selectively operative on compounds with a short acetyl chain although this enzyme also displays significant phospholipase A(1) activity.

Membrane-bound plasma platelet activating factor acetylhydrolase acts on substrate in the aqueous phase.

Human plasma platelet activating factor acetylhydrolase (pPAF-AH) is a phospholipase A(2) that specifically hydrolyzes the sn-2 ester of platelet activating factor (PAF) and of phospholipids with oxidatively truncated sn-2 fatty acyl chains. pPAF-AH is bound to lipoproteins in vivo, and it binds essentially irreversibly to anionic and zwitterionic phospholipid vesicles in vitro and hydrolyzes PAF and PAF analogues. Substrate hydrolysis also occurs in the absence of vesicles, with a maximum rate reached at the critical micelle concentration. A novel pre-steady-state kinetic analysis with enzyme tightly bound to vesicles and with a substrate that undergoes slow intervesicle exchange establishes that pPAF-AH accesses its substrate from the aqueous phase and thus is not an interfacial enzyme. Such a mechanism readily explains why this enzyme displays dramatic specificity for phospholipids with short sn-2 chains or with medium-length, oxidatively truncated sn-2 chains since a common feature of these lipids is their relatively high water solubility. It also explains why the enzymatic rate drops as the length of the sn-1 chain is increased. pPAF-AH shows broad specificity toward phospholipids with different polar headgroups. Additional results are that PAF undergoes intervesicle exchange on the subminute time scale and it does not undergo transbilayer movement over tens of minutes.

Percutaneous transluminal coronary angioplasty in a child with Kawasaki disease.

A successful attempt at percutaneous transluminanl coronary angioplasty (PTCA) to relieve stenosis of the mid-portion of the left anterior descending artery was achieved in a 6-year 9-month old boy who had multiple coronary aneurysms and stenosis due to Kawasaki disease. Despite the progression of coronary stenosis he had been well except for the perfusion defect of the anterior wall of myocardium on 99mTc-MIBI SPECT with dipyridamole infusion until PTCA was carried out after 4-year 4-months of the onset of illness. The area of stenosis was 70% before PTCA and 20% after PTCA. No restenosis at the site of PTCA was observed on follow-up angiography at 26 months after PTCA. This successful attempt may indicate that this procedure should be considered early in subclinical stenosis to prevent ischemic cardiac damage.

Adsorbate-induced pinning of a charge-density wave in a quasi-1D metallic chains: Na on the In/Si(111)-(4x1) surface.

We find that foreign adsorbates acting as local impurities can induce a metal-insulator transition by pinning a charge-density wave (CDW) on the quasi-1D metallic In/Si(111)-(4x1) chain system. Our scanning tunneling microscopy image clearly reveals the presence of a new local 4x2 structure nucleated by Na adatoms at room temperature, which turns out to be insulating with a doubled periodicity along the chains. We directly determine a CDW gap energy Delta = 105+/-8 meV by identifying a characteristic loss peak in our high-resolution electron-energy-loss spectra. We thus report the first observation of a local impurity-derived Peierls-like reconstruction of a quasi-1D system.